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what type of tests are available in php unit testing framework | assertions are available. PHP Unit Testing Framework PHP Unit Testing Framework is a unit testing framework that enables developers to discover bugs and in turn drive down the costs associated with developing PHP software. To remove the complications of trying to test software (that needs to be integrated) through a web server this framework uses the command line interface. This enables individual classes to be tested thoroughly before they are integrated together. The PHP Unit Testing Framework generates reports in either XML, XHTML or ASCII. The PHP Unit Testing Framework is one of the xUnit family of unit testing frameworks. | paq | 400 |
Age-dependent decrease of Nurr1 protein expression in the gerbil hippocampus | Age-dependent increase in the expression of antioxidant-like protein-1 in the gerbil hippocampus | s2orc_citation_titles | 16 |
Have been experiencing crushing depression. Went out and spent 30 minutes just walking around talking into a voice recorder, and I feel the best I've ever felt in a while. | I doubt this'll work for everyone, so I don't want to promise it as some catch-all solution. But I've struggled recently in coping with my depression, and at times it has seemed like it's never going away. Tonight I decided "fuck it" and just took a stroll around my neighborhood and ranted/explained/hashed out my mental issues into my phone's voice recorder for about half an hour. Then I played it back to myself. I don't really know what spawned the idea, but it's made me felt so much better about my mental state just being able to acknowledge to myself, verbally, how shitty things can be. This is gonna sound cheesy as fuck, but while playing the recording back to myself, I realized that although it seems like nobody can understand what I'm going through, at least \*I\* understand what I'm going through. | reddit_title_body | 541 |
On the Intra-Party Democracy Building in Post-disaster Reconstruction | "Taking the first step" for Party building in Post-disaster reconstruction,especially intra-Party democracy building,means that Party building should make creation from the following perspectives: arranging on new ideas as earlier as possible than other reconstruction work;at first striving for a new path in the disaster areas different from other non-earthquake-areas;reflecting the innovative concept differing other general areas as Mianyang is China Science and Technology City;and taking greater strides in the very bad Disaster areas such as Beichuan,especially conducting intra-Party democracy building,rather than other Party building tasks.Work emphasis of taking the first step is "four dedications to",basic principle is "four focuses on",protective condition is "four dependents on". | s2orc_title_abstract | 175 |
Very good product! this shoes fit very well | Very good product ! this shoes fit very well, it seem to run without shoes ! A+++ | amazon_reviews | 228 |
Brain AVM: Relationship of Angioarchitecture and Clinical Symptoms and Implications for Treatment | The clinical variability in the presentation of patients with brain arteriovenous malformations (B-AVM) may in part be due to the difference in host response to the presence of an AVM as demonstrated in the angioarchitecture. | s2orc_title_abstract | 26 |
Sr2RuO4 is an unconventional superconductor with a tetragonal structure, whereas Ca2RuO4 is a Mott insulator with orthorhombic symmetry. The substituted Ca2−xSrxRuO4 has yielded a rich phase diagram that is just beginning to be explored in detail. Experimental investigation of the resistivity ρ, susceptibility χ, specific heat Cp, Hall coefficient RH, and X-ray diffraction of Ca1.7Sr0.3RuO4 reveals a structural phase transition near T0 = 190 K and heavy-Fermion (HF) behavior below a coherence temperature T * ∼ 10 K, resembling that of the f -electron HF compound UPt3. The observation of T 2 -dependence of ρ below ∼ 0.5 K suggests a Fermi-liquid ground state. Based upon our data and theoretical calculations, we argue that the structural change at T0 may be responsible for the formation of the HF state. |
Sr2RuO4 is an unconventional superconductor with a tetragonal structure, whereas Ca2RuO4 is a Mott insulator with orthorhombic symmetry. The substituted Ca2−xSrxRuO4 has yielded a rich phase diagram that is just beginning to be explored in detail. Experimental investigation of the resistivity ρ, susceptibility χ, specific heat Cp, Hall coefficient RH, and X-ray diffraction of Ca1.7Sr0.3RuO4 reveals a structural phase transition near T0 = 190 K and heavy-Fermion (HF) behavior below a coherence temperature T * ∼ 10 K, resembling that of the f -electron HF compound UPt3. The observation of T 2 -dependence of ρ below ∼ 0.5 K suggests a Fermi-liquid ground state. Based upon our data and theoretical calculations, we argue that the structural change at T0 may be responsible for the formation of the HF state. The discovery of unconventional superconductivity in Sr 2 RuO 4 has stimulated great interest in the electronic properties of ruthenates. Despite its high electrical conductivity, a rather large ratio of the Coulomb repulsion (U ) to the bandwidth (W ) indicates that Sr 2 RuO 4 is close to a Mott transition. [1] Both strong electronelectron correlations and Fermi-liquid (FL) ground state appear to play a crucial role in its physical properties. In particular, intriguing connections have been revealed between these correlations and unconventional superconductivity. The partial substitution of the smaller Ca 2+ for Sr 2+ changes both U and W , leading to rich and unusual phenomena in Ca 2−x Sr x RuO 4 . [2] With increasing Ca content (decreasing x ), superconductivity is rapidly destroyed and the in-plane resistivity ρ ab increases, turning into insulating behavior (dρ ab /dT < 0) as x < 0.2. [2] This is consistent with the expected increase in the density of states (DOS) associated with the band narrowing due to the Ca substitution. [3,4] However, the magnetic properties are not in complete accord with this picture. It was found that the low-temperature paramagnetic susceptibility increases with Ca concentration, peaking at x = x c = 0.5. [5] Near this critical concentration, the effective magnetic moment tends to saturate with S = 1/2, [2] unexpected from band-structure calculations. [3] Neutron diffraction results suggest that the crystallographic distortion in Ca 2−x Sr x RuO 4 may lead to a variation in the shape and the effective filling of the triply degenerated Ru t 2g bands through a Jahn-Teller (JT) type orbital rearrangement. [6] Of particular interest is the intermediate regime with 0.2 ≤ x ≤ 0.5, where an electronic state containing both localized and itinerant electrons is proposed. [3] * email address: [email protected]
In this Letter, we report the electronic, magnetic and thermodynamic properties of Ca 1.7 Sr 0.3 RuO 4 (x ∼ 0.3) single crystals. Investigation of the specific heat C p and c-axis resistivity ρ c indicates a continuous phase transition at T 0 ∼ 190 K. Consistent with previous results, [2,6] a structural transition from tetragonal (T > T 0 ) to orthorhombic (T < T 0 ) symmetry is observed. This leads to the deviation of the magnetic susceptibility χ from simple Curie behavior above T 0 to Curie-Weisslike character below T 0 . Remarkably, the Hall coefficient R H , measured by applying H perpendicular to ab-plane (H c), behaves similarly to χ c (H c): R H (T) scales with χ c (T) above T * ∼ 10 K, a characteristic temperature corresponding to a maximum χ c and R H . This behavior has been attributed to skew scattering due to magnetic moment effects in heavy-fermion (HF) systems such as UPt 3 . [7] Surprisingly, the resistivity ρ ab,c and specific heat C p also reveal features remarkably similar to those of UPt 3 below T * . A large Sommerfeld coefficient γ = 266 mJ/mol-K 2 also provides evidence for HF behavior in Ca 1.7 Sr 0.3 RuO 4 , unexpected in a 4d -electron system. To our knowledge, this is the first report of a 4d -electron material exhibiting HF behavior. In contrast to previous conclusions based upon resistivity measurements above 0.3 K [5], we find that the resistivities ρ ab,c follow T 2 -dependence below ∼ 0.5 K, showing a recovery of a Fermi-liquid ground state in the high Ca concentration regime. Again, this is similar to what is observed in UPt 3 . We discuss this heavy-electron behavior in terms of recently developed theoretical models.
Single crystalline Ca 1.7 Sr 0.3 RuO 4 was grown using an NEC SC-M15HD image furnace. For feed-rod preparation, a mixture of CaCO 3 , SrCO 3 and RuO 2 , with molar ratio of 1.70:0.30:1.15, was pre-reacted in air at 1100 • C for 12 h. After regrinding, the powder was pressed into rods and heated in air at 1100 • C for another 12 h. Single crystals were grown using a feed rate of 30 mm/h and a (2) 5.320 (2) 12.551 (7) 355.2(2) growth rate of 15 mm/h in an atmosphere of 10% oxygen and 90% argon. Shiny black crystals are produced with actual Ca:Sr ∼ 1.7:0.3 as determined by energy dispersive X-ray analysis. The crystal structure was refined using an Enraf-Nonius four-circle autodiffractmeter with Mo Kα radiation and a nitrogen-gas-stream cryocooler. Table I presents the lattice parameters at various temperatures between 100 and 200 K. Note that a < b at T < 200 K, indicating that the system undergoes a structural change from tetragonal at high temperatures to orthorhombic symmetry at low temperatures, in good agreement with that obtained by neutron diffraction. [6] As given in Table I, there is no drastic change in cell volume between 160 and 200 K. Below 160 K, the refinement data show negative thermal expansion along the b-axis while both a and c continuously decrease with decreasing T. These results suggest that the structural phase transition is continuous. This is confirmed by specific heat data. Fig. 1 shows the temperature dependence of the specific heat C p of a Ca 1.7 Sr 0.3 RuO 4 single crystal between 0.38 and 300 K. Note a kink occurs at a characteristic temperature T 0 ∼ 190 K, corresponding to the structural phase transition. No hysteresis was observed in specific heat, which is consistent with a continuous phase transition.
T (K) a (Å) b (Å) c (Å) vol. (Å 3 ) 200 K 5.320
For a non-magnetic metallic solid, the low-temperature specific heat C p is usually analyzed by considering contributions from electrons (C e p = γT) and lattice (C l p = βT 3 ), i.e., C p = γT+βT 3 . Here, γ and β are T-independent constants. Thus, a plot of C p /T vs. T 2 should be linear. For Ca 1.7 Sr 0.3 RuO 4 , the temperature dependence of C p /T between 0.38 and 20 K is shown in the inset of Fig. 1. The nonmonotonic T 2 -dependence of C p /T with a dip at T * ∼ 10 K indicates a departure from normal metallic behavior in Ca 1.7 Sr 0.3 RuO 4 . We recall that a similar temperature dependence of C p /T has been seen in HF materials, [8] which can be expressed as [9]
C P = γT + βT 3 + δT 3 ln(T /T i ),(1)
where δ and T i are constants. The last term describes the contribution from interactions between quasiparticles due to spin fluctuations, where T i is a cut-off temperature with regard to the spin fluctuations. [8,9] Using Eq. 1 to fit our specific heat data between 0.38 and 13 K yields that γ = 266 mJ/mol-K 2 , δ = 1.86 mJ/mol-K 4 and β-δlnT i = -5.48 mJ/mol-K 4 . As illustrated in the inset of Fig. 1 by the solid line, the above formula fits the experimental data (0.38 -13 K) quite well. The γ value extracted from the above fitting procedure is large compared with the parent compound Sr 2 RuO 4 (γ = 37.5 mJ/mol-K 2 [10]) and is comparable to HF materials such as UPt 3 (γ = 422 mJ/mol-K 2 [11]). Heavyelectron behavior was first recognized in f -electron systems. Recently, similar behavior has also been seen in the 3d transition metal oxide LiV 2 O 4 . [12] In general, HF behavior is not anticipated in systems containing 4d /5d electrons because of the extended nature of these orbitals.
In a Fermi-liquid system, information about the effective mass of the quasiparticles can be extracted from the low-temperature electrical resistivity when expressed as ρ = ρ 0 + AT 2 as T → 0 K. Here, the residual resistivity ρ 0 and coefficient A are constants. According to Kadowaki and Woods (KW), the ratio A/γ 2 is expected to approach the universal value A/γ 2 = 1.0×10 −5 µΩ cm/(mJ/mol-K) 2 , if the electronic conduction and specific heat are governed by the same quasiparticles. [13] Shown in Fig. 2 are the temperature dependences of the ab-plane and c-axis resistivities of Ca 1.7 Sr 0.3 RuO 4 between 0.05 and 300 K, measured using a standard fourprobe technique. Note that ρ ab increases with temperature (dρ ab /dT > 0), reflecting the itinerant nature of electrons. The c-axis resistivity ρ c , however, undergoes a crossover from metallic behavior (dρ c /dT > 0) at T < T 0 to non-metallic character (dρ c /dT < 0) at T > T 0 . Although ρ ab and ρ c of Ca 1.7 Sr 0.3 RuO 4 superficially resemble those of undoped Sr 2 RuO 4 , it is clear that the metallic-nonmetallic transition in ρ c of Ca 1.7 Sr 0.3 RuO 4 is due to the structural change, which shortens the lattice parameter c and subsequently enhances the interlayer coupling below T 0 . Interestingly, ρ ab remains metallic without any noticeable anomaly, although lattice parameters a and b are also spontaneously changed (see Tab. I). Nevertheless, it is obvious that a sharp decrease occurs in both ρ ab and ρ c below ∼ 10 K, coincident with the characteristic temperature T * in C p /T (see the inset of Fig. 1). In light of previous results, we note that such behavior can only be seen if 0.2 < x < 0.5. [2] In this regime, the low-temperature resistivity has been analyzed using ρ = ρ 0 + AT α , with α < 2, leading to the conclusion of non-FL ground state. [5] In contrast, we find that, for Ca 1.7 Sr 0.3 RuO 4 , both ρ ab and ρ c are well described by ρ = ρ 0 + AT 2 below ∼ 0.5 K as shown in the inset of Fig. 2, characteristic of a Fermi-liquid ground state. The fits from 50 to 500 mK give A ab = 1.88 µΩ cm/K 2 and A c = 88.8 µΩ cm/K 2 . Similar to what was found in Sr 2 RuO 4 , A c ≫ A ab , indicating that the quasiparticles essentially form a 2D Fermi liquid. We estimate that A ab /γ 2 = 2.7×10 −5 µΩ cm/(mJ/mol-K) 2 , comparable to the expected universal value.
Given the heavy-mass Fermi-liquid behavior of Ca 1.7 Sr 0.3 RuO 4 , it is natural to expect a large spin susceptibility. Measurements of the magnetic susceptibility χ were performed using a SQUID magnetometer. Fig. 3a displays the temperature dependence of χ at 0.1 T between 2 K and 300 K. Measurements performed in both zero-field-cooling and field-cooling conditions yield identical results. It may be seen that χ ab,c shows strong temperature dependence. This local moment behavior is strongly in contrast with the relatively T-independent Pauli paramagnetism and superconductivity observed in undoped Sr 2 RuO 4 . Below ∼ 50 K, anisotropy becomes apparent. While χ ab (H ab) tends to saturate below ∼ 3.5 K, χ c (H c) clearly reveals a peak at T * ∼ 10 K. Again, these features resemble those observed in UPt 3 . [11] Interestingly, both χ ab and χ c vary smoothly with temperature without noticeable anomaly across T 0 . It was reported that, except for near x = 2, χ of Ca 2−x Sr x RuO 4 can be described by a Curie-Weiss (CW) law in a wide temperature regime. with T between 25 K and T 0 . This indicates that χ ab,c can be expressed as
χ = C/(T − θ), 25K < T < T 0 ,(2)
where θ is the CW temperature and C is the Curie constant. For Ca 2−x Sr x RuO 4 , it is well justified to assume that C = N A µ 2 B g 2 S(S+1)/3k B , as the orbital angular momentum for transition metal ions is quenched. [14] Here, N A is the Avogadro's number, g = 2, k B is the Boltzmann's constant and µ B is the Bohr magneton. Our fits for the range 25 K < T < T 0 (solid lines in Fig. 3b) yield S = 0.55 and θ ab = -2.4 K from χ ab (T), and S = 0.66 and θ c = -9.5 K from χ c (T). However, both χ ab and χ c appear to slowly deviate from the CW behavior above T 0 , and tend to follow a simple Curie law (χ ∝ T −1 ) as demonstrated in the inset of Fig. 3b. This implies that the interactions between local moments become important due to the structural change. The negative θ ab and θ c suggest antiferromagnetic (AF) spin interactions within the ab-plance and along the c-direction below T 0 . While evidence for long-range magnetic order has not been found, [6] the peak in χ c indicates that short-range AF correlation develops along c-direction below T * , consistent with the downturn of the resistivity (see Fig. 2) and the upturn of C p /T (see Fig. 1).
The above analysis indicates that the magnetic susceptibility of Ca 1.7 Sr 0.3 RuO 4 is dominated by the spin susceptibility. Thus, the Wilson ratio, R W = π 2 k 2 B χ spin /3µ 2 B γ, may be estimated using χ spin = χ. Given the saturated value χ ab = 0.0333 cm 3 /mol below 3.5 K, we obtain R W = 1.7, exceeding the value of unity expected for free electrons. For comparison, we estimate R W = 1.7 -3.2 for UPt 3 using the data given by Ref. [11]. It may be seen that the values of R W are similar in the two systems.
Considering Hund's coupling in the t 2g bands and the large crystal field splitting in a 4d system, the S = 1 configuration is naturally expected for Ca 2−x Sr x RuO 4 . However, our susceptibility data yield S = 0.55 -0.66, in agreement with previous work. [2] A theoretical investigation [3] suggests that this unusual behavior is driven by the crystal structural distortion (tilting and rotation of RuO 6 octahedra), which narrows the (xz , yz )subbands and changes the crystal field splitting. In the regime of 0.2 < x < 0.5, it was proposed that 3 electrons in the (xz , yz )-subbands are localized and produce a net local moment of S = 1/2. The remaining electron is in the itinerant xy-band and is responsible for the metallic character. Within this picture, the conduction band is essentially half-filled.
To test the above proposal, Hall measurements were performed by applying current I along the ab-plane (I ab) and magnetic field H along the c-direction (H c). Fig. 4 presents the temperature dependence of the Hall coefficient R H (hollow circles) at 8 Tesla between 2 and 300 K. Note that R H is positive and shows strong temperature dependence over the entire temperature range. Similar to χ c , upon cooling, R H initially increases and then decreases, revealing a peak around 14 K. For comparison, we replot χ c into Fig. 4 (solid circles). Remarkably, the two sets of data scale very well between 14 and 300 K without any adjustable parameters. A similar scaling relationship has been seen in UPt 3 . [7] In the latter material, the temperature-dependent R H above T * is interpreted as the sum of an ordinary Hall coefficient R 0 , arising from the Lorentz force, and an extraordinary term representing the incoherent skew scattering from local moments, i.e., R H can be described by
R H = R 0 + 4πχR s ,(3)
where R s is a T-independent constant. Using Eq. 3 and χ = χ c , we fit our R H data between 15 and 300 K, yielding R 0 = 7.22×10 −11 m 3 /C and R s = 2.65×10 −3 mol/C. The rather small R 0 suggests the conduction band is close to half-filling, consistent with the theoretical prediction cited above. Finally, it should be mentioned that R H of Ca 1.7 Sr 0.3 RuO 4 resembles that of UPt 3 not only at high temperatures but also in the coherent state. As shown in the inset of Fig. 4, R H exhibits a T 2 dependence below T * , as has also been observed in UPt 3 . [7] This implies that the anomalous Hall effect in both systems results from the same scattering mechanism. In summary, our C p (T), ρ(T), χ(T), R H (T) and Xray diffraction measurements on Ca 1.7 Sr 0.3 RuO 4 indicate a continuous structural transition at T 0 ∼ 190 K, be- low which AF interactions between local moments develop. Remarkably, physical properties such as the upturn in C p /T, the downturn in ρ(T), χ(T) and R H (T), and the T 2 -dependence of ρ and R H below T * ∼ 10 K resemble those of the 5f HF compound UPt 3 , making Ca 1.7 Sr 0.3 RuO 4 the only known 4d -HF material. This strongly suggests a similar underlying mechanism for the heavy-electron behavior in these two systems, characterized by the large γ, χ and A values.
PACS numbers: 61.66.-f, 71.27.+a, 72.15.Eb, 72.80.Ga
FIG. 1 :
1Temperature dependence of the specific heat of a Ca1.7Sr0.3RuO4 single crystal between 0.38 and 300 K. Note a kink occurs at T0 ∼ 190 K. The inset is the specific heat data between 0.38 and 20 K plotted as Cp/T vs. T 2 . Note that Cp/T reaches a minimum at T * ∼ 10 K. The solid curve is the fit of experimental data between 0.38 and 13 K to Eq. 1 (see the text).
FIG. 2 :
2Temperature dependence of the ab-plane electrical resistivity of Ca1.7Sr0.3RuO4 in both ab-plane (ρ ab ) and cdirection (ρc) between 0.05 K and 300 K. The inset is the plot of ρ ab,c versus T 2 .
[ 2 ]FIG. 3 :
23For Ca 1.7 Sr 0.3 RuO 4 , we plot the susceptibility data as χ −1 ab,c vs. T as shown in Fig. 3b. Note that both χ −1 ab and χ −1 c vary approximately linearly (a) Temperature dependence of the magnetic susceptibility χ ab (H ab) and χc(H c) at H = 0.1 Tesla. Note χc reveals a peak at T * ; (b) Magnetic susceptibility data plotted as χ −1 vs. T. The solid lines are the fits of experimental data to Eq. (2).
FIG. 4 :
4Temperature dependence of the Hall coefficient RH (hollow circles) at H = 8 Tesla. For comparison, χc(T) (solid circles) is also plotted. Inset illustrates the T 2 dependence of RH below 14 K.
TABLE I :
ILattice parameters and lattice volume in Ca1.7Sr0.3RuO4 at T = 200, 160, 140, 120 and 100 K.
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| s2orc_abstract_body | 65 |
What is your opinion on a foreign soldier joining ADF & vice versa? | I know the ADF is one of the few militaries that openly recruits foreigners with prior military experience. Just wanted to open a discussion on this topic.
I've tried to discuss this before the topic of treason came up. I didn't understand how treason can apply here as the ADF would only recruit those who have previously served towards it's national interests (i.e. troops from the US etc.). | reddit_title_body | 324 |
SGLT2 Inhibition with Empagliflozin Increases Circulating Provascular Progenitor Cells in People with Type 2 Diabetes Mellitus. | Hess et al. quantified circulating aldehyde dehydrogenase-expressing (ALDHhi) cell subsets in people with T2DM given either empagliflozin (EMPA) or placebo. EMPA treatment increased circulating pro-angiogenic CD133+ progenitor cells, decreased pro-inflammatory ALDHhi granulocyte precursors, and increased ALDHhi monocytes with M2 polarization. EMPA treatment improved T2DM-associated "regenerative cell depletion" contributing to enhanced vascular health. | s2orc_title_abstract | 111 |
what is the mean of bpm in tempo | and fake book music for jazz or popular music may use several terms, and may include a tempo term and a genre term, such as "slow blues", "medium shuffle" or "fast rock". Here follows a list of common tempo markings. The beats per minute (bpm) values are very rough approximations for time. These terms have also been used inconsistently through time and in different geographical areas. One striking example is that "Allegretto" hastened as a tempo from the 18th to the 19th century: originally it was just above "Andante", instead of just below "Allegro" as it is now. As another | paq | 244 |
who wrote the letter describing the eruption of pompeii | Pompeii Pompeii () was an ancient Roman city near modern Naples in the Campania region of Italy, in the territory of the comune of Pompei. Pompeii, along with Herculaneum and many villas in the surrounding area (e.g. at Boscoreale, Stabiae), was buried under of volcanic ash and pumice in the eruption of Mount Vesuvius in AD 79. Many of the inhabitants were also buried before they could escape. The catastrophe was described in a surviving letter by Pliny the Younger who saw the eruption from a distance and described the death of his uncle Pliny the Elder, an admiral of | paq | 141 |
Anywhere to take a shower on St.George campus that isnt a gym? | already know the gym has showers but feels weird going into the gym just to take a shower
Sometimes i get super sweaty riding my bike to school
anywhere else on campus to take a shower? | reddit_title_body | 238 |
I NEED MY MONEY BACK OR A BATTERY REPLACEMENTE SOME ONE RETURN MY PHONE CALLS AND MESSAGES AT LEAST !!! | I receibe my battery like I did last time about a year ago and I didn't have a probliem, recently I bought the same battery and I doesn want to work in my phone displaying a message about "use a genuine battery" and then turned off, I been calling to complain to the number provided and nobody never answer me the phona I left several voice messeages already and noby has return my messages until today, I am so desapont | amazon_reviews | 340 |
Pair of marijuana applications filed in county | A recently released report details requests for a pair of marijuana cultivator licenses for Union County.
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why is heterosexuality a more stable sexual orientation | Sexual fluidity 63.6% of lesbians, 64.7% of bisexual females, 9.52% of gay males, and 47% of bisexual males. According to the study, "this pattern was consistent with the hypothesis that heterosexuality is a more stable sexual orientation identity, perhaps because of its normative status. However, male homosexual identity, although less stable than heterosexual identity, was relatively stable compared to the other sexual minority identities". Having only adults included in the examined group, they did not find the differences in fluidity which were affected by age of the participants. However, they stated that "research on attitude stability and change suggests most change occurs | paq | 42 |
Primary source, for those interested in the French-Ottoman connection of the 16th century | The title pretty much sums up the primary reason to order this book - it is a primary source (in French) of a servant to the French ambassador to Suleiman I. The effectiveness and quality of information is uneven, so depending on your specific topic of interest, this book may or may not be for you. Let me illustrate my point . . .
As Jean Chesneau (the author and servant) reaches Venice and Constantinople, his descriptions are rich with detail and meaty possibility. However, since the introduction (which is written by an 19th century Frenchman) describes his reasons for editing/publishing Chesneau's work as being a more complete summary of the travels that the French took with Suleiman throughout the Middle East, the expectation - at least for me - involved a misconception: that the entire book would be as descriptive as the beginning. This is not so. As Chesneau describes their travels from place to place, he often simply states that they traveled to a place, spent the night, then moved on to a different place, and spent the night, and so forth. This is not to say that he NEVER describes any of the places, but those details are somewhat scarce, considering that their travels are a good two-thirds of his accounting.
I also want to mention his descriptions of Jerusalem, the Church of the Holy Sepulchre, and the situation between the Muslim and Christian populations. If your interest lies in 16th century church history, or church history in general, Chesneau's descriptions are fairly complex and provide much insight into an issue that has existed for centuries. Just be aware that the information you desire is a fairly small portion of this particular journal.
For those of you who feel that you may have some interest in part of Chesneau's descriptions, I would like to point out that you can look at this book, in its entirety, in several places online. I purchased a paper copy for two reasons: first, I am an English-speaker primarily, and I wanted to be able to underline and define words within the text; and second, I am using it for my thesis, and I wanted to write notes in the margins to my hearts' desire.
All in all, I'm satisfied with my purchase because it satisfies my needs, but I wish I had looked more carefully at the online version, in regards to the lack of description within the travel portion. If I had noticed the scant nature of the details, I might have chosen another primary source for my work. | amazon_reviews | 341 |
A PTAS for the minimization of polynomials of fixed degree over the simplex | We consider the problem of computing the minimum value pmin taken by a polynomial p(x) of degree d over the standard simplex Δ. This is an NP-hard problem already for degree d = 2. For any integer k ≥ 1, by minimizing p(x) over the set of rational points in Δ with denominator k, one obtains a hierarchy of upper bounds pΔ(k) converging to pmin as k → ∞. These upper approximations are intimately linked to a hierarchy of lower bounds for pmin constructed via Polya's theorem about representations of positive forms on the simplex. Revisiting the proof of Polya's theorem allows us to give estimates on the quality of these upper and lower approximations for pmin. Moreover, we show that the bounds pΔ(k) yield a polynomial time approximation scheme for the minimization of polynomials of fixed degree d on the simplex, extending an earlier result of Bomze and De Klerk for degree d = 2. | s2orc_title_abstract | 298 |
National Skin Center for acne scars | I am planning to go to polyclinic and get a referral to NSC for my acne scars particularly for my back. I finished 3 months of doxycycline given by the polyclinic one month ago and it worked well for me.
Do any of you guys have experience going to NCS for acne scars treatment? What is the cost of going for one chemical peel session for the back? Is it cheaper if i do my treatment in other clinics and any recommendations? | reddit_title_body | 586 |
what type of glass are mosque lamps made from | called "smalto". Mosque lamps are made of enamelled glass. They generally have lugs, from which they are suspended to light not only mosques, but also similar spaces such as madrassas and mausoleums. They have a religious symbolism based on the Quranic verse of light, with which they are often calligraphed. During the European Renaissance, expensive enamelled goblets were used as courtship and marriage gifts. These goblets were rarely used, and some have survived. Glass painting involves painting on glass, with glass, making the finished work transparent. Glass fusing is similar, but powders are not mixed into a paintable paste first; | paq | 173 |
Enhancement of the Long-Term Permeance, Selectivity Stability, and Recoverability of Pd–Au Membranes in Coal Derived Syngas Atmospheres | Two new large scale (200 cm2) composite Pd and Pd–Au membranes were prepared and tested in an actual coal derived, but desulfurized, syngas in order to further quantify permeance loss due to species other than sulfur and to determine the nature of the contaminants. As in our previous work, membranes were tested at the National Carbon Capture Center (NCCC) in Wilsonville, Alabama. Before the syngas test, the Pd and Pd–Au membranes had thicknesses of 7 and 6.6 μm, H2 permeances at 450 °C of 17.7 and 29.2 N m3 m–2 h–1 bar–0.5, and H2/He selectivities higher than 2700 and 160 000, respectively. The two membranes produced H2 at an exceptionally high purity level of 99.8–99.9%. The selectivity of the Pd–Au membrane was stable for over 473 h in an actual syngas atmosphere at 450 °C and 12.6 bar demonstrating the high robustness and suitability of these membranes in industrial environments. However, as seen in our previous study, the two membranes showed a decrease in H2 permeance upon syngas introduction (rangin... | s2orc_title_abstract | 171 |
Background:The role of ATM kinase activity in DNA replication was unknown. Results: ATM kinase inhibition, but not ATM protein disruption, impedes DNA replication, and ATM physically and functionally interacts with proliferating cell nuclear antigen to regulate DNA synthesis. Conclusion: ATM regulates DNA synthesis and binds to the replication machinery. Significance: ATM kinase inhibition affects DNA replication in a different manner to ATM protein disruption.Grants CA148644 (to C. J. B.), GM57479 (to A. E. T. ), and P30CA047904. |
Ataxia telangiectasia (A-T) is a pleiotropic disease, with a characteristic hypersensitivity to ionizing radiation that is caused by biallelic mutations in A-T mutated (ATM), a gene encoding a protein kinase critical for the induction of cellular responses to DNA damage, particularly to DNA double strand breaks. A long known characteristic of A-T cells is their ability to
synthesize DNA even in the presence of ionizing radiation-induced DNA damage, a phenomenon termed radioresistant DNA synthesis. We previously reported that ATM kinase inhibition, but not ATM protein disruption, blocks sister chromatid exchange following DNA damage. We now show that ATM kinase inhibition, but not ATM protein disruption, also inhibits DNA synthesis. Investigating a potential physical interaction of ATM with the DNA replication machinery, we found that ATM co-precipitates with proliferating cell nuclear antigen (PCNA) from cellular extracts. Using bacterially purified ATM truncation mutants and in vitro translated PCNA, we showed that the interaction is direct and mediated by the C terminus of ATM. Indeed, a 20-amino acid region close to the kinase domain is sufficient for strong binding to PCNA. This binding is specific to ATM, because the homologous regions of other PIKK members, including the closely related kinase A-T and Rad3-related (ATR), did not bind PCNA. ATM was found to bind two regions in PCNA. To examine the functional significance of the interaction between ATM and PCNA, we tested the ability of ATM to stimulate DNA synthesis by DNA polymerase ␦, which is implicated in both DNA replication and DNA repair processes. ATM was observed to stimulate DNA polymerase activity in a PCNAdependent manner.
Ataxia telangiectasia (A-T) 2 is a rare autosomal recessive human disorder characterized by neurodegeneration, immunodeficiency, an increased risk of cancer, and profound radiosensitivity (1). Cells derived from A-T patients are radiosensitive, contain increased chromosome aberrations, and exhibit cell-cycle checkpoint defects following exposure to ionizing radiation (1). These cell cycle checkpoint defects include a delayed arrest at G 1 /S and G 2 /M as well as an inability to arrest ongoing DNA replication in cells exposed to ionizing radiation, a phenomenon described as radioresistant DNA synthesis. Radioresistant DNA synthesis is caused by a defect in the inhibition of late origin firing in A-T cells following ionizing radiation (2). The contribution of DNA chain elongation arrest to the intra-S-phase checkpoint has been difficult to establish, because the DNA lesions that activate the checkpoint also directly arrest replication fork progression. However, early reports suggest that A-T cells have a slightly longer S-phase and contain an increase in replication intermediates relative to controls (3,4).
Several observations suggest that mere checkpoint abrogation is unlikely to be the cause for the cellular radiosensitivity of A-T cells. For instance, holding irradiated A-T cells in prolonged periods of either G 1 or G 0 , and thus giving them ample time to repair the damage (as would occur under wild-type conditions), still leads to increased levels of chromosome aberrations in A-T cells (5). The requirement of A-T mutated (ATM) for the repair of a small fraction of double strand breaks after ␥-irradiation (6) or after cleavage by the endonuclease I-PpoI (7) directly implicate ATM in signaling to the DNArepair machinery. It was proposed that ATM is particularly needed for the repair of double strand breaks in heterochromatin (8). * This work was supported, in whole or in part, by National Institutes of Health
The gene defective in A-T patients, ATM, encodes a serine/ threonine protein kinase that is critical for the induction of cellular responses to DNA damage, particularly to DNA double strand breaks (9). ATM kinase activity is increased following exposure to as little as 0.05 gray (Gy) of ionizing radiation and following the introduction of just two DNA double strand breaks (10). More than 1000 substrates of ATM and the related kinase A-T and Rad3-related (ATR) have been identified (11,12). Although gene ontology analyses identified groups of substrates implicated in biological processes as diverse as immunity and defense, cell proliferation and differentiation, intracellular protein traffic, cell structure and motility, and the cell cycle, the largest group of 202 substrates was categorized as nucleoside, nucleotide, and nucleic acid metabolism (11). Of these 202 protein substrates, 46 are proteins implicated in DNA replication, recombination, and repair, and these include the large and fourth subunit of DNA polymerase ⑀ as well as DNA polymerase and DNA polymerase (11). Neither the effects of a selective ATM kinase inhibitor on DNA replication nor the functional significance of these phosphorylations on DNA polymerase substrates have been reported. To our knowledge, whether small molecule ATM kinase inhibitors induce radioresistant DNA synthesis has not been investigated.
We previously reported that ATM kinase inhibition, but not ATM protein disruption, blocks sister chromatid exchange, a phenotype attributed to the repair of damaged DNA replication forks, following DNA damage (13). Here we show that ATM kinase inhibition, but not ATM protein disruption, also inhibits DNA synthesis. Investigating a potential physical interaction of ATM with the DNA replication machinery, we found that ATM interacts with proliferating cell nuclear antigen (PCNA) both in vivo and in vitro. PCNA was originally characterized as an essential component of the eukaryotic DNA replication machinery wherein it functions as a DNA sliding clamp that enhances the processivity of replicative DNA polymerases (14). Subsequently PCNA was found to recruit other DNA-modifying enzymes, including repair proteins as diverse as DNA ligase I, XP-G, FenI, and MSH2 and -6 (15).
Using purified ATM truncation mutants we show that the interaction between ATM and PCNA is direct and mediated by the C terminus of ATM. A 20-amino acid region close to the ATM kinase domain was found to be sufficient for strong binding to PCNA. The peptide sequence mediating the interaction (ATM PBP) is distinct from previously identified PCNA-interacting motifs such as the PIP and KA boxes, and the observed binding is specific to ATM, because the homologous regions of other PIKK members, including the closely related kinase A-T and Rad3-related, do not bind PCNA. Because PCNA is known to stimulate DNA synthesis by DNA polymerase ␦ (pol␦), in both DNA replication and several DNA repair processes, we tested the effect of ATM PBP in an in vitro DNA synthesis assay. We show that ATM stimulates DNA polymerase ␦ activity in a PCNA-dependent manner.
EXPERIMENTAL PROCEDURES
Cell Culture, Transfection, and Expression Vectors-H460 large cell lung cancer cells were cultured in RPMI, and IMR90 lung fibroblasts, 293T embryonic kidney cells, and U2OS osteo-sarcoma cells were kept in DMEM, both supplemented with 10% fetal calf serum. Transfections were conducted according to the manufacturers' instructions using FuGENE6 (Roche Applied Science) for U2OS cells and Lipofectamine (Invitrogen) for 293T cells. Expression vectors for ATM without the 3Ј-untranslated region (UTR) were constructed by cutting a previously described ATM expression vector containing the 3Ј-UTR (16) with Bsu36I and XhoI and inserting an ATM C-terminal DNA sequence lacking the 3Ј-UTR, obtained by amplification with the appropriate primers.
In Vivo DNA Synthesis Assays-Cellular DNA synthesis was measured by subsequent incubation with medium containing 14 C-or 3 H-labeled thymidine as described (2). Incubation of cells with 14 In Vivo Interaction Assays-Whole cell lysates of H460 or U2OS cells were prepared by washing cells in PBS, lysing in TGN buffer (150 mM NaCl, 5 mM NaF, 1% Tween 20, 0.5% Nonidet P-40, 50 mM Tris-HCl, pH 7.5, protease inhibitors) on ice for 30 min and twice clearing by centrifugation. For immunoprecipitation of endogenous PCNA, lysates were incubated with antibodies against PCNA for 5 h and precipitated after four washes with TGN buffer. Anti-rabbit immunoglobulins served as the negative control. The immunoprecipitates with Protein A/G-agarose beads were tested for PCNA and ATM by immunoblots. Alternatively, in the case of exogenous PCNA, FLAG-tagged PCNA or hemagglutinin (HA)-tagged ATM was expressed in U2OS cells. 48 h after transfection the cells were washed, and the lysate was cleared by centrifugation and incubated with M2-agarose for 8 h. After washes with BC buffer (20 mM Tris-HCl 7.9, 20% glycerol, 0.2 mM EDTA, 0.5 mM PMSF, 1 mM DTT) with 150 mM KCl, the beads were boiled in reducing SDS buffer for elution. Inputs and eluates were examined by immunoblotting with antibodies against PCNA and ATM. In the case of the reciprocal immunoprecipitation, 293T cells were transfected with FLAG-tagged ATM and co-precipitation of ATM and PCNA was assessed in the same way. When investigating DNA dependence on the co-immunoprecipitations, lysates were incubated with M2-agarose in the presence or absence of 20 g/ml ethidium bromide (Invitrogen) or 100 units of DNase I (Roche Applied Science).
In Vitro Interaction Assays-GST-fused proteins were expressed in Rosetta(DE3)pLysS cells at 30°C and harvested 4 -4.5 h after induction with 0.4 mM isopropyl 1-thio--D-galactopyranoside in bacterial lysis buffer (20 mM HEPES (pH 7.9), 500 mM NaCl, 1 mM EDTA, 10% glycerol, 0.1% Nonidet P-40, 1 mM DTT, 0.5 mM PMSF). Lysates were obtained by sonicating the bacterial resuspension and were cleared by ultracentrifugation (Sorvall T647.5, 35,000 rpm, 30 min, 4°C).
Appropriate amount of lysates were incubated with 10 l of glutathione-Sepharose for at least 6 h and washed three times with BC buffer with 300 mM KCl and once with BC buffer with 100 mM KCl. Proteins were labeled with 35 S-labeled methionine using TNT reticulate lysates, following the standard protocol provided by Promega (Madison, WI). In vitro translated proteins were incubated with resin-bound proteins (10 g) by rotating at 4°C for 4 h in BC buffer containing 100 mM KCl and 0.05 g/l BSA. After several washes with BC buffer containing 100 mM KCl and 300 mM KCl, the resin was boiled in SDS loading buffer before subjecting to SDS-PAGE. Gels were incubated in Amplify TM (Amersham Biosciences) before drying and autoradiography to enhance the signal.
In Vitro DNA Synthesis Assays-DNA synthesis assays were carried out as described previously (17) with minor modifications. Briefly, a 5Ј-end-labeled primer (41 nucleotides: 0.05 pmol) annealed to a template (94 nucleotides) was extended by DNA polymerase ␦ (pol ␦: 0.1 pmol) in the absence or presence of PCNA (0.25 pmol of trimer), replication factor C (RFC) (0.05 pmol), and indicated peptides for 15 min at 37°C in a 40-l reaction buffer containing 20 mM HEPES (pH 7.5), 100 mM NaCl, 10 mM MgCl 2 , 2 mM ATP, 40 M dNTP mix, 0.1 mg/ml BSA, and 0.01% Triton X-100. All the peptides used in the DNA synthesis assays were diluted in DMSO, and all the reactions were adjusted to a final concentration of 2.5% DMSO, which did not interfere with DNA synthesis by pol ␦. Reaction products were resolved by electrophoresis in denaturing 12.5% polyacrylamide gels and analyzed by using a PhosphorImager. ATM peptides consisted of a fluorescein-labeled tat-fused peptide from ATM, GRKKRRQRRRPPQLVTIQSFKAEFRLAGGVN-LPK, and its mutant derivative, GRKKRRQRRRPP-QLVEIQEFKAEFRLAGGVNLPK.
RESULTS
Acute ATM Kinase Inhibition Suppresses Cellular DNA
Synthesis-We recently showed that ATM kinase inhibition, but not ATM protein disruption, blocks sister chromatid exchange following DNA damage (13). To determine whether ATM kinase inhibition also influences DNA synthesis, we labeled the DNA of IMR90 human lung fibroblasts expressing shRNA, which disrupts ATM, or of a GFP-expressing control line (Fig. 1C, left panel) with 14 C-labeled thymidine for one cycle. Cells where then divided and treated with the ATM kinase inhibitor KU60019 or vehicle from 30 min prior to a pulse of 30 min with 3 H-labeled thymidine to the end of the pulse. At the end of the pulse the cells were harvested, and the incorporation of 3 H and 14 C into high molecular weight material was then measured. The ratio of 3 H over 14 C was used as a measure for relative DNA synthesis. Treatment with ATM inhibitor more than halved thymidine incorporation during the observed time interval in IMR90 cells, whereas DNA synthesis was not affected in IMR90 with disrupted ATM (Fig. 1A). The observed inhibitory effect of KU60019 on DNA synthesis is therefore ATM-dependent. Similarly, we tested the H460 large cell lung cancer cells with wild-type or knockdown levels of ATM (Fig. 1C, right panel). Again KU60019 inhibited DNA synthesis in an ATM-dependent manner (compare the first two lanes in the left and right panels in Fig. 1B). Irradiation of H460 with 5 Gy of ionizing radiation decreased DNA synthesis in an ATM-dependent manner (compare the first and third lanes in the left and right panels in Fig. 1B) as expected given the well established phenomenon of radioresistant DNA synthesis caused by ATM deficiency. Treatment with KU60019 decreased DNA synthesis even further in irradiated IMR90 with wild-type ATM levels. We next wanted to test whether a kinase-inactive ATM mutant showed a similar phenotype as observed with ATM inhibition. To do so we reconstituted ATM knockdown cells with wild-type or mutant ATM. The mutant ATM, ATM D2870A,N2875K, has been described previously (16) and lacks kinase activity. Fig. 1D shows part of the 3Ј-UTR of ATM mRNA. The underlined nucleotides are targeted by the shRNA vector used to make stable knockdown cell lines. A Bsu36I/XhoI double restriction of the expression vectors as well as sequencing was used to verify the lack of 3Ј-UTR in the wild-type and kinase activity-deficient ATM ( Fig. 1E and under "Experimental Procedures"). An ATM vector lacking the 3Ј-UTR, but not an ATM vector containing the 3Ј-UTR, was able to reconstitute the ATM knockdown cell line (Fig. 1F). ATM knockdown cells expressing similar amounts of wild-type or kinase activity-deficient ATM (Fig. 1G) were used for DNA synthesis assays. Although wild-type ATM did not affect DNA synthesis, ATM lacking kinase activity strongly decreased DNA synthesis (Fig. 1H). Abolition of kinase by mutation and inhibition thus show the same phenomenon. The ATM inhibition-mediated stalling of DNA replication is associated with activation of Chk1 signaling as evidenced by phosphorylation of Chk1 at serine 317 ( Fig. 1I) observed 1 h after ATM inhibition. Given that acute ATM inhibition, but not ATM disruption inhibited DNA synthesis, we speculated that ATM might interact with the replication machinery per se and interfere with DNA synthesis if kinase-inactivated.
ATM Interacts with PCNA in Vivo-PCNA plays a key role in DNA replication and DNA repair by forming a sliding homotrimeric ring around DNA that serves as a docking platform for the recruitment of various DNA-modifying enzymes to the replication fork. Such enzymes include nucleases, ligases, helicases, and most importantly DNA polymerases (14). By tethering these enzymes to the DNA template, PCNA increases the processivity and catalytic activity of the machineries involved in DNA synthesis.
Because of the unique ubiquitous role of PCNA in DNA synthesis processes and to study the role of ATM in DNA synthesis, we tested whether ATM binds to PCNA. Whole cell lysates of H460 cells were incubated with antibodies against PCNA and precipitated. Anti-rabbit immunoglobulins served as negative control. The immunoprecipitates with Protein A/G-agarose beads were tested for PCNA and ATM by immunoblotting. ATM co-precipitated with PCNA independently of cell irradiation or treatment with the ATM-specific kinase inhibitor KU60019 (Fig. 2A, compare lanes 1 to 4 and lanes 5 to 8). To further corroborate the physical interaction of ATM with PCNA in vivo, FLAGtagged PCNA or HA-tagged ATM were expressed in U2OS cells and the tagged PCNA precipitated with M2 (anti-FLAG)-agarose. After repeated washes the eluates were tested for the presence of PCNA and ATM. Endogenous ATM co-precipitated with PCNA, whereas no ATM was detected in the control cells transfected with HA-tagged ATM (Fig. 2B, compare lanes 1 and 2). Similarly, we expressed FLAG-tagged ATM in 293T cells (allowing better expression of ATM than U2OS) and found PCNA to co-precipitate with endogenous ATM (Fig. 2C). Lysate from untransfected cells served as control. To test whether the interaction of PCNA with ATM was mediated by DNA, we co-precipitated ATM and FLAG-tagged PCNA in the presence or absence of ethidium bromide or DNase. Neither treatment affected ATM co-precipitation with PCNA (Fig. 2D), indicating that DNA was neither bridging the interaction partners nor required for potential conformational changes associated with the interaction. ATM Directly Interacts with PCNA in Vitro-ATM is a protein of ϳ350 kDa of 3056 amino acids. Despite its size, relatively few direct interaction partners have been identified to date.
Examples of such binding partners include ATM itself (ATM forms a homodimer) (10), Tel2 (18), and the MRN complex (19). To establish whether PCNA binds ATM directly and to determine the regions involved in the interaction, bead-immobilized GST-fused ATM fragments purified from bacteria were incubated with in vitro translated 35 S-labeled PCNA and washed. Eight overlapping fragments spanning the entire protein (scheme and Coomassie stain in Fig. 2E) were probed for PCNA binding. Labeled PCNA that bound GST-ATM fusion proteins was resolved by SDS-PAGE, and the gels were dried and exposed to film. PCNA binds directly to the C terminus of ATM, in particular to the fragments with amino acids 2400 -2700 (F7) and 2680 -3056 (F8) (Fig. 2E, upper left panel). The ATM C terminus encompasses the kinase domain (ϳ2680 -2960), the PIKK-regulatory domain (ϳ2960 -3025), and the FATC domain (ϳ3025-3056) (20). We next set out to fine map of the interaction domain of ATM and PCNA by truncating the C terminal bait even further (Fig. 3C). Using this iterative approach (Fig. 3, A and B), we found that the 21 ATM residues 2680 -2700 are sufficient for the interaction with PCNA. This PCNA-binding peptide (PBP) is close to the catalytic site of ATM and is rich in hydrophobic residues.
Binding to PCNA Is Not Conserved among PIKK Members -ATM is a member of the phosphatidylinositol 3-kinase-related kinases (PIKKs), a family of serine/threonine protein kinases that includes A-T and Rad3-related, the catalytic sub-unit of DNA-dependent protein kinase, suppressor of morphogenesis in genitalia, mammalian target of rapamycin, and transformation/transcription domain-associated protein. To test whether PCNA binding is specific to ATM PBP or conserved in the analogous regions in other PIKK members (see Fig. 3D for a sequence alignment), we purified GST-tagged fusions of all corresponding PIKK peptides (Fig. 3D, lower left panel). Bead-immobilized GST-fused PIKK fragments were incubated with in vitro translated 35 S-labeled PCNA and washed either with low salt or high salt buffers. PCNA binding was specific for ATM (Fig. 3D, upper left panel). Weak binding to mammalian target of rapamycin was observed under low (100 mM KCl), but not under higher salt (300 mM KCl) conditions. Of note, the fragment from the highly related A-T and Rad3-related kinase did not bind PCNA. Because PCNA binding to ATM PBP was not disrupted by increased salt concentrations, the interaction is probably mediated by hydrophobic residues.
The Interaction of PCNA with ATM Does Not Require the PCNA Interconnector Loop-To determine where PCNA is bound by ATM we incubated bead-immobilized GST-fused ATM residues 2400 -2700 or 830 -1290 (as control) with in vitro translated 35 S-labeled PCNA truncations. ATM interacted with both the N and C termini of PCNA, but not with a central fragment of residues 106 -192 (Fig. 4A). The PCNA N-terminal residues 1-140 or the C-terminal residues 185-261 were sufficient for PCNA binding to ATM-(2400 -2700). To confirm that ATM PBP (fragment 2680 -2700) is sufficient for these interactions, we repeated the experiment with beadbound GST-PBP. Again, the N and C termini of PCNA bound the shorter ATM fragment, but the central region of PCNA failed to do so (Fig. 4B). The crystal structure of PCNA revealed that it is a homotrimer forming a closed circular ring in which the C terminus of one monomer interacts tightly with the N terminus of the next one. Interestingly the C-and N-terminal domains of the monomer show structural similarity, each consisting of a 9-stranded antiparallel  sheet with two attached ␣ helices, so that the ring is composed of six topologically identical domains (21). The major interaction sites of PCNA with partners are a hydrophobic pocket between the two domains of each monomer and the long loop connecting the two domains. Examples of proteins binding in that region are DNA pol ␦, p21 (22), and flap endonuclease (Fen1) (23). These proteins contain a so-called PIP (PCNA-interaction protein) box with a QXX(M/ L/I)XX(F/Y)(F/Y) consensus motif. The PIP boxes have been shown to bind to the interconnector loop in PCNA. Interestingly, ATM PBP does not bind to the PCNA interconnector loop (Fig. 4B, the interconnector loop spans PCNA amino acids 119 -134), in agreement with the absence of a PIP consensus motif in the ATM PBP sequence.
To further define the PCNA interaction sites for ATM PBP, we attempted to generate shorter PCNA truncations but found that several translated very poorly. Nevertheless, we were able to show with two reasonably expressing fragments that PCNA region 42-120 bound very well to ATM PBP, whereas PCNA-(1-45) did not (Fig. 4C). Fig. 4D shows a model of the structure of human PCNA obtained from the Molecular Modeling Database, MMDB ID 31339 (24). The left panel shows the trimeric structure of PCNA with the DNA binding helices colored in green, the  sheets in orange, and the interconnecting loop in blue, indicated by an arrow. The middle panel shows PCNA with the N-terminal (45-106) and C terminal (185-261) regions of one monomer that are sufficient for ATM PBP binding colored in orange and red, respectively. The interaction sites of PCNA with ATM determined by deletion mutagenesis would indicate that ATM-(2680 -2700) binds the grove between the domains of a PCNA monomer (Fig. 4D). The interconnecting loop is neither needed for the interaction nor does it bind on its own (Fig. 4, B and C). The side view of PCNA in Fig. 4D, right panel, shows that the interaction of the ATM peptide is likely on the opposite face of where RFC and DNA pol ␦ bind (indicated by an arrow in the left panel), as deduced from the crystal structure of yeast PCNA with yeast RFC (25) and human PCNA with a peptide derived from the pol p66 subunit (23). Because crystal structures suggest that, as expected, DNA polymerases in general bind to the same side of the ring (26), the binding of ATM is unlikely to interfere with PCNA-DNA polymerase interactions.
ATM Stimulates PCNA-dependent DNA pol ␦ Activity-DNA pol ␦ is one of the three replicative polymerases and is believed to be the enzyme primarily responsible for lagging strand synthesis (27). Pol ␦ is also involved in DNA repair by filling the gap during mismatch repair and nucleotide excision repair and extending the invading strand in homologous recombination (28,29). The activity of pol ␦ is strongly stimulated by PCNA and RFC, the clamp loader for PCNA (17) (Fig. 5A). To determine whether binding of ATM could influence PCNA-dependent DNA polymerase activity, we assayed DNA synthesis in vitro with recombinant proteins. In a primer extension assay containing pol ␦ and PCNA, DNA synthesis was stimulated by the addition of increasing amounts of an ATM-(2680 -2700) peptide (compare lanes 1 to 3 in Fig. 5C). High concentrations of the same peptide inhibited pol ␦ in the same assay (lane 4, Fig. 5C). A quantitation of three independent experiments is shown in Fig. 5D.
Because the interaction of ATM PBP is not disrupted by 300 mM KCl (Fig. 3D), we speculate that the binding to PCNA is mediated by hydrophobic residues. We therefore hypothesized that mutating the ATM threonine 2682 and serine 2685 to the charged residue glutamic acid, which is also a phosphomimetic, would interfere with the binding of PBP to PCNA. We purified GST-ATM-(2680 -2720) and GST-ATM-(2680 -2720)-2682E,2685E (see Coomassie stain in Fig. 5B, lower panel) and tested the interaction of PCNA with these bead-immobilized proteins. The mutant ATM fragment bound PCNA 6 -8 times weaker than wild-type (Fig. 5B, upper panel).
We then compared the ability of the wild-type and mutant ATM peptides, ATM-(2680 -2700) and ATM-(2680 -2700)-2682E,2685E, to stimulate pol ␦ in vitro. The wild-type ATM fragment stimulated DNA synthesis by pol ␦ to a greater extent than the mutant fragment compromised in PCNA binding (compare lanes 2 to 3 with lanes 5 to 6 in Fig. 5C). Similar results were observed when purified GST-ATM-(2680 -2720) and GST-ATM-(2680 -2720)-2682E,2685E were used in the DNA synthesis assay (data not shown). Unlike the wild-type ATM peptide, the PCNA-binding-impaired peptide did not inhibit pol ␦ at higher concentration (compare lanes 4 and 7 in Fig. 5C and see the quantitation in Fig. 5D).
Finally we tested the effect of wild-type and mutant ATM fragments on pol ␦ in the presence of both PCNA and RFC. Both wild-type and mutant ATM peptides inhibited DNA synthesis under these conditions, but the wild-type ATM peptide had a much stronger inhibitory effect than the mutant ATM peptide with the lower affinity for PCNA. In summary, these observations indicate that ATM does interact with PCNA and can influence PCNA activity in vitro. The interaction assays with PCNA deletion mutants suggest that ATM-(2680 -2700) interacts with PCNA in the grove between two monomer domains (Fig. 4D). It could be that pol ␦ preferentially interacts with PCNA when one or more of three potential peptide binding sites on the trimer are unoccupied at low peptide peptide concentrations, whereas occupancy of the three binding sites at higher peptide concentration inhibits the interaction with pol ␦. The maximum stimulatory effect on the peptide on DNA synthesis by pol ␦ and PCNA was 6-to 10-fold, whereas RFC stimulates the same reaction more than 100-fold as a consequence of active PCNA loading (Fig. 5D and data not shown). The inhibitory effect of the ATM peptide on RFC-stimulated DNA synthesis could be due to reduced loading of PCNA trimers bound by the peptide.
DISCUSSION
Following our initial observation that an ATM-specific inhibitor influences DNA synthesis in an ATM-dependent manner, we investigated whether ATM binds to PCNA, a docking platform for many factors involved in DNA replication and DNA repair. Surprisingly, we found that ATM and PCNA physically interact both in vivo and in vitro. We were able to define the ATM site sufficient for PCNA binding to a small region near the ATM kinase domain. This small peptide, ATM PBP, stimulates DNA pol ␦ in a PCNA-dependent manner in an in vitro assay.
ATM Binding to PCNA Does Not Involve a PIP Box-Unlike many other PCNA interacting proteins, the ATM fragment sufficient to bind PCNA does not have a motif that would fit the consensus of either a PIP box or a related KA box (described in Ref. 30). Consistent with the absence of a PIP box, this interaction is not mediated by the PCNA interconnector loop that plays an essential role in p21 (22), pol ␦3 (p66), and FEN1 binding (23). ATM is a 350-kDa protein that forms a dimer in solution when in its inactive state (10). Future studies will determine whether ATM binds to PCNA as a monomer or as a dimer. Our interaction data with ATM fragments suggest that ATM dimerization is not needed for PCNA binding, and it is probable that monomerization is needed to expose the region close to the kinase domain for the interaction. Of note, theoretically trimeric PCNA contains three identical binding sites for a partner. Nevertheless, given ATM's size it is unlikely that three ATM molecules could simultaneously bind the trimeric ring. Instead it is possible that ATM and the DNA polymerase share PCNA as a docking platform during DNA synthesis.
Regulation of PCNA-ATM Interaction-Recent studies have shown that PCNA activity is highly regulated by post-translational modification (31). For instance, mono-ubiquitylation of PCNA at Lys-164 facilitates the recruitment of translesion synthesis polymerases that enable DNA damage bypass, whereas poly-ubiquitylation of the same residue dislodges translesion synthesis polymerases from PCNA enabling a template-switching mechanism in the error-free pathway of post-replication repair. At least in yeast, PCNA is also SUMOylated at Lys-164 and Lys-127 resulting in the inhibition of recombination via recruitment of Srs2 or inhibition of cohesion establishment via repulsion of Eco1 respectively (32,33). Future studies will show whether the interaction of PCNA with ATM is also regulated by post-translational modification of PCNA or -as in the case of p21, RFC1 and Fen1 (31) by phosphorylation of its binding partner.
PCNA as a Recruiter of ATM-Previously identified interacting partners of PCNA include proteins involved in DNA replication, DNA repair, cell cycle control, sister chromatid cohesion, and chromatin assembly and maintenance (30). Our novel finding that ATM binds PCNA suggests that PCNA plays a role in the early stage of DNA damage signaling by ATM.
PCNA is a key factor of several cellular processes involving DNA synthesis, such as DNA replication, DNA repair, and homologous recombination. Our initial observation that ATM inhibition leads to decreased DNA synthesis is likely due to an inhibition of DNA replication during S phase, given the extent of change in thymidine incorporation observed. In view of the physical interaction of PCNA with ATM and the resulting stimulation of DNA pol ␦, it is tempting to speculate that ATM recruitment to the replication fork plays a role in the surveillance of ongoing replication. Interestingly, several reports on the early characterization of A-T cells found that those cells had a decreased DNA synthesis rate and prolonged S phase compared with normal cells (3,4). Yet, an alternative possibility would place the actual function of the interaction of PCNA with ATM after replication forks stalls or collapses, particularly at the stage of homologous recombination following double strand break formation. In this regard, PCNA was found to be required for recombination-associated DNA synthesis by pol ␦ (28), and PCNA and pol ␦ specifically were reported to be needed for break-induced replication (34), a homologous recombination pathway used when only one end of the double strand break shares homology with a template. The idea that ATM regulates PCNA function at the recombination step is particularly attractive, because we found ATM inhibitors to decrease both DNA synthesis and DNA damage-induced sister chromatid exchange (13). Furthermore, in both cases kinase inhibition does not phenocopy protein loss, leading us to speculate that ATM inhibition leads to ATM physically blocking the dynamic repair processes involved in homologous recombination (35).
FIGURE 1 .
1ATM inhibition affects DNA synthesis. A, acute ATM inhibition decreases DNA synthesis. IMR90 cells with wild-type or knockdown levels of ATM were treated with ATM kinase inhibitor KU60019 and assayed for DNA synthesis. B, H460 cells with wild-type (left panel) or knockdown levels of ATM (right panel) were treated with ATM kinase inhibitor KU60019 and/or 5 Gy of ␥-irradiation before assaying for DNA synthesis. C, immunoblot of IMR90 and H460 with wild-type and knockdown levels of ATM. HSC70 served as loading control. D, partial sequence of the 3Ј-UTR of ATM. Underlined nucleotides were targeted by a shRNA vector to knockdown ATM. E, ATM vectors with and without 3Ј-UTR. Vectors for ATM mRNA with (lane 1) and without 3Ј-UTR (lanes 2 and 3; wild-type (WT), kinase-inactive mutant (KI)) were digested with Bsu36I and XhoI. F, efficiency of shRNA-mediated ATM knockdown. H460 cell lines with stable ATM knockdown or a scrambled control were transiently transfected with FLAG-tagged ATM expression vectors lacking or containing the 3Ј-UTR of ATM. Lysates were probed for ATM and FLAG by immunoblotting. The asterisk denotes a nonspecific band, the arrow FLAG-ATM. G, immunoblot of reconstituted ATM knockdown cells derived from H460. Lysates of knockdown cells transfected with shRNA-resistant expression vectors for wild-type (WT) or kinase-inactive mutant (KI) ATM were probed for ATM and FLAG. Untransfected knockdown cells and H460 with scrambled shRNA served as control. H, kinase-inactive mutant ATM inhibits DNA synthesis. Knockdown cells reconstituted with wild-type (WT) or kinase-inactive mutant ATM were assayed for DNA synthesis. I, ATM kinase inhibition activates Chk1 signaling. H460 with wild-type or knockdown levels of ATM were treated with the ATM inhibitor KU60019 for 1 h or not, and the lysates assayed by immunoblotting for Chk1 and ATM as well as their activating phosphorylation status. shATM, shRNA against ATM.
FIGURE 2 .
2Direct interaction of ATM with PCNA. A, in vivo interaction of ATM with PCNA. PCNA from H460 cells treated in the indicated way was precipitated with an antibody against PCNA. Bound material was washed and analyzed by immunoblotting. Mock precipitates from identically treated cells served as negative controls. B, exogenous PCNA interacts with endogenous ATM. U2OS cells were transfected with a vector for either HA-tagged ATM or FLAG-tagged PCNA. Inputs (4%) and anti-FLAG (M2-agarose) immunoprecipitates were tested for ATM and PCNA. C, exogenous ATM interacts with endogenous PCNA. HEK293T cells were transfected with a vector for FLAG-tagged PCNA or not. Inputs (4%) and anti-FLAG (M2-agarose) immunoprecipitates were tested for ATM and PCNA. D, the interaction between PCNA and ATM is not mediated by DNA. Cells were transfected with FLAG-tagged PCNA. The inputs and anti-FLAG immunoprecipitates from lysates in the absence or presence of ethidium bromide (EtBr) or DNase were tested for ATM. Lysates from untransfected cells served as negative control. E, verification and mapping of binary ATM-PCNA interactions. GST alone or GST-fused truncation mutants of ATM were bound to glutathione-Sepharose and incubated with in vitro translated,35 S-labeled PCNA. Beads were washed, and eluted proteins were analyzed by autoradiography after SDS-PAGE. The lower panel shows a scheme, and the upper right panel shows a Coomassie stain of GST-fused ATM fragments. The interaction site of the ATM with PCNA lies within the C terminal regions F7 (2400 -2700) and F8 (2680 -3056) (upper left panel). f, FLAG tag; ha, HA tag; IP, immunoprecipitation; shATM, shRNA against ATM.
FIGURE 3 .
3A and B, GST-fused truncation mutants of ATM were used to narrow down the interaction domain with PCNA. Interaction assays were done as described in Fig. 2E. ATM amino acids 2680 -2700 (PBP) were sufficient to bind PCNA. C, scheme of GST-fused ATM truncations used. D, comparison of homologous regions in the PIKK family and their interaction with PCNA. GSTfused ATM PBP, but not the homologous peptides in other members of the human PIKK family interact with PCNA (upper left panel). The lower left panel shows a Coomassie stain of GST-PIKK fragments, and the right panel shows a sequence comparison of them. Hydrophobic residues in the ATM peptide are underlined.
FIGURE 4 .
4A, in vitro translated truncation mutants of PCNA were used to narrow the domains of PCNA mediating the interaction with ATM. ATM-(2400 -2700) binds to both the C and N termini of PCNA, as evidenced by the interaction of PCNA truncation mutants with ATM. ATM-(830 -1290) served as negative control. B, GST-ATM-(2680 -2700) (PBP) is sufficient to bind PCNA. Of note, the interconnecting loop in fragment 106 -192 did not bind ATM. C, ATM PBP binds to amino acids 41-120 of PCNA. Arrows indicate PCNA fragments 1-45 and 42-120 in the input. D, model of PCNA. The left panel shows the trimeric structure of PCNA with the DNA binding helices in green, the  sheets in orange, and the interconnecting loop in blue indicated by an arrow. The structure of human PCNA was from the Molecular Modeling Database, MMDB ID 31339 (24). The central panel shows a planar view of PCNA with the regions of a monomeric subunit sufficient to bind the ATM-(2680 -2700) peptide colored in orange (45-106) and red (185-261). The right panel shows a side view of PCNA. The face bound by DNA polymerases and RFC is indicated by an arrow. fl, full length.
FIGURE 5 .
5A, DNA synthesis assays with DNA pol ␦, PCNA, and RFC. A primer extension assay was used to test the effect of PCNA and RFC on DNA pol ␦ activity. B, mutant ATM-(2680 -2720)-2682E,2685E peptide has a lower affinity for PCNA than wild-type ATM-(2680 -2720). Interaction assays with wild-type and mutant ATM PBP show the lower affinity of the mutant with PCNA (upper panel shows a GST pulldown assay of in vitro translated PCNA; the lower panel shows a Coomassie stain of the baits.). C, DNA synthesis assays with DNA pol ␦ and PCNA with or without RFC were done in the presence or absence of wild-type or mutant ATM peptides. The PCNA-binding peptide of ATM-(2680 -2700) (ATMwt) stimulates DNA synthesis several-fold in the absence of RFC and inhibits it in the presence of RFC. D, quantitation of DNA synthesis shown in C. ATM-(2680 -2700) (ATMwt) shows a much stronger ability to stimulate PCNA-dependent DNA pol ␦ activity than ATM-(2680 -2720)-2682E,2685E (ATMmut). This figure shows ratios of fully extended primers over total primers as determined by autoradiography. Error bars represent standard deviations of three independent experiments.
Kudos Pharmaceuticals) was used at 1 M concentration. Cells were ␥-irradiated in a Shepherd Mark I Model 68 137 Cs irradiator (J. L. Shepherd & Associates).C was for 16 h, with 3 H for 30 min. In the case of
reconstitution experiments ATM knockdown cells were
labeled with 14 C before transfection with the indicated ATM
expression vector. Tritium labeling was done 24 h after
transfection.
Antibodies, Inhibitors, and Irradiation-Antibodies against
ATM were purchased from Sigma; those against PCNA and
heat shock cognate 70 (HSC70) were from Santa Cruz Biotech-
nology. KU60019 (
VOLUME 287 • NUMBER 15 • APRIL 6, 2012
Acknowledgment-We thank Dr. Titia de Lange for some of the GSTfused ATM expression vectors.
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| s2orc_abstract_body | 35 |
The effect of phenotypic variation on attachment of Pseudomonas tolaasii and P. putida to Agaricus bisporus mycelium was investigated. Quantitative studies demonstrated the ability of each isolate to attach rapidly and firmly to A. bisporus mycelium and significant differences in attachment of wild-type and phenotypic variant strains were observed. This was most pronounced in P. tolaasii, where the percentage attachment of the wild-type form was always greater than that of the phenotypic variant. The medium upon which the bacteria were cultured, prior to conducting an attachment assay, had a significant effect on their ability to attach. Attachment of the wild-type form of P. putida was enhanced when the assay was performed in the presence of CaCl2, suggesting the involvement of electrostatic forces. No correlation was observed between bacterial hydrophobicity and ability to attach to A. bisporus mycelium. Scanning electron microscopy confirmed the results obtained from the quantitative studies and provided further evidence for marked differences in the ability of the pseudomonads to attach to mycelium. Fibrillar structures and amorphous material were frequently associated with attached cells and appeared to anchor bacteria to each other and to the hyphal surface. A time-course study of attachment using transmission electron microscopy revealed the presence of uneven fibrillar material on the surface of cells. This material stained positive for polysaccharide and may be involved in ensuring rapid, firm attachment of the cells. | BackgroundPseudomonas tolaasii is a problematic pathogen of cultured mushrooms, forming dark brown ‘blotches’ on mushroom surfaces and causing spoilage during crop growth and post-harvest . Treating P. tolaasii infection is difficult, as other, commensal bacterial species such as Pseudomonas putida are necessary for mushroom growth, so treatments must be relatively specific.ResultsWe have found that P. tolaasii is susceptible to predation in vitro by the δ-proteobacterium Bdellovibrio bacteriovorus. This effect also occurred in funga, where B. bacteriovorus was administered to post-harvest mushroom caps before and after administration of the P. tolaasii pathogen. A significant, visible improvement in blotch appearance, after incubation, was observed on administration of Bdellovibrio. A significant reduction in viable P. tolaasii cell numbers, recovered from the mushroom tissue, was detected. This was accompanied by a more marked reduction in blotch severity on Bdellovibrio administration. We found that there was in some cases an accompanying overgrowth of presumed-commensal, non-Pseudomonas bacteria on post-harvest mushroom caps after Bdellovibrio- treatment. These bacteria were identified (by 16SrRNA gene sequencing) as Enterobacter species, which were seemingly resistant to predation. We visualised predatory interactions occuring between B. bacteriovorus and P. tolaasii on the post-harvest mushroom cap surface by Scanning Electron Microscopy, seeing predatory invasion of P. tolaasii by B. bacteriovorus in funga. This anti-P. tolaasii effect worked well in post-harvest supermarket mushrooms, thus Bdellovibrio was not affected by any pre-treatment of mushrooms for commercial/consumer purposes.ConclusionsThe soil-dwelling B. bacteriovorus HD100 preys upon and kills P. tolaasii, on mushroom surfaces, and could therefore be applied to prevent spoilage in post-harvest situations where mushrooms are stored and packaged for sale. | s2orc_abstract_citation | 74 |
Another Good Argument for Further Human Speciation | Some of you may have read my speciation argument here:
Here I used various viable hybridizations in nature between species that are as divergent as the difference between Whites and blacks to argue that we are not necessarily the same species.
Speciation is the process by which scientists taxonomically categorize species between each other. Most people believe that this is scientifically and objectively defined on whether the populations are able to breed. This could not be further from the truth:
**Why is this important**
Some of you reading this may be thinking, "why is he focusing on this and why does he think it is so important? Isn't it more important to convince people that we should have separate countries with Whites having their own?" The answer to the first question is inside my answer to the second, which is yes and no. The rhetorical strength of the argument made by our opponents is in what I would like to refer to as "The Tower of Diversity" and it goes something like this:
A Diverse Nation is Viable and Preferable
|
Mixing and Miscegenation is Fine
|
Races Do Not Exist we are all part of the "Human Race"
|
We Are All the Same Species/Subspecies
They have built this "Tower of Diversity" by claiming the reverse to be true of human beings. If the bottom of the tower is not true, the rest do not follow. Unfortunately for our opponents, it is the weakest level but it is so close to the ground that while we focus on the top of the tower, they stay busy covering the bottom up with trees and bushes.
If we can destroy the bottom of this tower, the rest will come crashing down around them. This is why people like David Duke, with his wonderfully produced videos and sound logic, are failing to make their arguments. They fail to recognize that they have completely forgone the base of this tower. This is why their arguments do not reach enough of an audience. The audience is convinced we are all the same species/subspecies undeserving of protection and separation.
**The next argument**
Anyway, onto my new argument, the Orangutan. The Orangutan is not one defined as one species but two, the Bornean and Sumatran. Please take a moment and compare these two "species" with a plethora of various subspecies:
Bornean
Sumatran
Now, as if you didn't know, let us compare the differences between these specimens and these:
Asian
European
African
If these two nearly identical "species" and multiple "subspecies" of Orangutan, all of which can and do interbreed in the wild, can be categorically defined as distinct and separate, then it should not be difficult for us to make the argument that the different human populations are, at least, separate subspecies. | reddit_title_body | 47 |
American partners seem to be moving ahead with the TPP without America & China seems to be doubling down on it's own regional trade deal in opposition to America; What will the long-term effect of this be? | >Remaining members of the Trans Pacific Partnership (*TPP*) free trade agreement are working on a statement to reaffirm their commitment to it, despite the withdrawal of the United States, sources close to the discussions said.
>__________
>Japan is leading the countries that still want to persist with the much more comprehensive TPP agreement, abandoned by Trump in one of his first acts in office and which does not include China.
>_____________
>Sources close to the discussions said the so-called TPP-11 nations - the 11 left after the United States withdrew - were planning a statement of commitment to the pact.
>________
>In other talks on the sidelines, China will be driving for progress on its favored trade deal for Asia: the Regional Comprehensive Economic Partnership.
>The free trade agreement doesn't cover as many areas as the TPP deal or demand tough conditions for members on issues such as protecting intellectual property, labor rights or the environment.
>_________
>Given the uncertainty over TPP, the China-backed deal was now the priority for Malaysia | reddit_title_body | 276 |
... human and weak even God's children are tempted not perfect. Very good reading and looking forward to reading ... | A new view on how human and weak even God's children are tempted not perfect. Very good reading and looking forward to reading the rest. | amazon_reviews | 185 |
Rocket League for Nintendo Switch needs the option to turn off vsync. | The title says it all. I don't care if I have screen tearing and frame drops. I cant time anything right with the crazy amount of input lag this game has on switch. Why not give us the ability to turn on and off vsync? You gave us the ability to have the "Quality" mode.. which literally makes the game completely unplayable.
This is coming from a PC player with the dream of pocket league. I'm champ in 2s and 3s and can't even compete against the ball chasing plats. Extremely frustrating.
I get better input lag on a crappy laptop with Intel shared graphics running 33-50fps in basically 480p. Still a better experience than switch rocket league. I tried to make myself like it but I just can't. | reddit_title_body | 307 |
A Little Book Packed Plum Full of SF | San Francisco is a great place to explore - it is compact, photogenic and well-served by public transportation. Seeing the famous sites is fine but the true San Francisco experience is found in strolling the streets and nosing around the stores of its eclectic neighborhoods. The Little Black Book of SF is a handy guide for just such an SF adventure. The book is small enough to fit into most pockets while the spiral bound construction inside a sturdy cover and thick pages insure that it is going to stand up to the rigors of your SF adventure. This book is not a thorough discussion of all things SF but rather a heads up of what to look for once you find yourself in Cow Hollow or Bernal Heights or any of the City's other districts. There are 10 handy little maps at the start of each district chapter followed by recommendations of what to see, where to shop, where to eat,drink and dance as well as what might be interesting to the kids. If you are a person that likes to travel light while in search of the genuine culture, this book is for you. | amazon_reviews | 340 |
what college baseball team plays in bannerwood park | Behind home plate is the largest, seating 200 people. On the sides to that by the dugouts are smaller bleachers that seat 50 people each. The official capacity of Bannerwood Park is 300, but there is lots of room to stand and watch or sit in your own folding chair down the foul lines into the outfield. Bannerwood Park Bannerwood Park is a baseball venue in Bellevue, Washington, United States. It is home to the Seattle Redhawks baseball team, a member of the NCAA Division I Western Athletic Conference. The venue features lighting, bleacher seating, concessions, and restrooms. On February | paq | 241 |
Adorable sentiment, etched well | Adorable sentiment, etched well, glass is not heavy at all so I deducted one star for that, I prefer things like me a bit heavier.
I would purchase again certainly. | amazon_reviews | 63 |
How do you unlock your lg rumor2 phone from sprint? | How do you unlock your lg rumor for t mobile? | wikianswers | 84 |
who was the mistress of kott in martian time slip | Martian Time-Slip otherwise move in a jerky, uncoordinated manner. Heliogabalus, to Manfred, moves smoothly and gracefully. He seems to talk to Manfred without words. The precipitating event of the story is the suicide of Manfred Steiner's father Norbert which has the effect of connecting Kott to Manfred and also depriving Otto Zitte, a colleague of Norbert's, of his livelihood. The crux of the story is a meeting between Kott, Bohlen and Kott's mistress, Doreen Anderton, at Kott's home, with Manfred in tow. This episode is previewed three times before it actually occurs, apparently through Manfred's eyes but with participation by Bohlen. Each | paq | 135 |
I need some help doing Max damage(up to the cap) in a chain attack. | I have about 240 hours in the game, but I can't seem to find any video explaining how to deal 9999999 damage in a chain attack. Can someone list items and strategies. I can get 7 orbs, but the full burst happens with pneuma before I can get all 7 bursted. Even so the damage isnt as close to the cap as I'd like. What am I doing wrong?
Edit:grammar | reddit_title_body | 368 |
Using Implicit Context to Ease Software Evolution and Reuse | Software systems should consist of simple, conceptually clean components interacting along narrow, well-defined paths. All too often, this is not reality: complex components end up interacting for reasons unrelated to the functionality they provide. We refer to knowledge withina component that is not conceptually required for the individual behaviour of that component as extraneous embedded knowledge (EEK). EEK creeps in to a system in many forms, including dependences upon particular names and the passing of extraneous parameters. This paper proposes implicit context as a means for reducing EEK in systems. Implicit context combines a mechanism to reflect upon what has happened in a system through queries on the call history with a mechanism for altering calls to and from a component. We demonstrate the benefits of implicit context by describing its use to reduce EEK in the Java Swing library. | s2orc_title_abstract | 261 |
High-resolution velocity modeling by seismic-airborne TEM joint inversion: A new perspective for near-surface characterization | We discuss the use of helicopter-borne transient electromagnetic (HTEM) for a high-resolution spatial and vertical characterization of the near surface in a structure-controlled wadi in central Saudi Arabia. In this area, seismic data quality is poor, and seismic imaging suffers from a combination of scattering effects — due to swarms of faults reaching the surface — and large velocity variations occurring along subvertical boundaries between the wadi sediment infill and the surrounding carbonate plateaus. HTEM was selected from a suite of nonseismic methods for multiparameter velocity-model building to enhance the velocity estimation for the wadi and surrounding areas. HTEM data were modeled by performing spatially constrained 1D resistivity inversion to obtain a high-resolution image of the near surface with sensitivity to a depth of 400–500 m from the surface. Sharp boundaries of the wadi and fine vertical layering, obtained from the HTEM inversion, provide detailed information about the parameter vari... | s2orc_title_abstract | 6 |
SevereHCF - 1.0 [3rd April 2015] | First of all, welcome to the SevereHCF Reddit! This was an idea sparked up amongst the staff team and is a simple cost effective way of running the community discussions.
//Finish this// | reddit_title_body | 150 |
what type of belief allows evidential support for all of our justified beliefs | level of supporting beliefs: they can only justify if they're themselves justified, and evidentialism therefore demands an even deeper level of supporting belief. And so on. According to this argument, a justified belief requires an endless supply of reasons. Some philosophers such as Thomas Nagel posit that this is an absurd conclusion. In general, responses to this argument can be classified in the following ways: Of the main responses, coherentism and skepticism are clearly consistent with evidentialism. Coherentism allows evidential support for all of our justified beliefs in the face of the regress argument by allowing for circular chains of | paq | 136 |
A Strategic Concept of Building a Big Sports Circle on the Yangtse River Delta | In view of the geographical locations of Jiangsu Province, Ahejiang Province and the city ofShanghai as well as the present situation and development tendency of sports in the area, theauthorelaborates on the guiding ideology and basic frame of building a big sports circle on the YangtseRiver Delta. Some relevant ideas and suggestions are also put forward in the article. | s2orc_title_abstract | 243 |
What is the best way to clear and flatten an area 60 meters by 30 meters of brush? I do not have access to large tools | Hello, I have a piece of land (60 metes by 30 meters) that I need to flatten to make into a field (grass or clover). It is currently full of rocks/roots/ruts and thick brush to the point that I cannot use a riding lawn mower or hand push one. What would be the best way to tackle this without using heavy equipment (I can't get it into the space)? I do have a solid week with nothing else to do so time isn't a factor.
My idea so far is to do the following:
1. Clear brush with industrial weed wacker (with the metal blades)
2. Remove tree root/small stumps/rocks with ATV and Come-along or hand tools
3. Rent a soil compactor to flatten the earth
4. mix soil / seeds and spread an even thin layer over the flattened earth
The plan is that with the earth now being flat I can use a riding lawn mower to cut down any returning brush and give the grass/clover the opportunity to take over.
Any advice? | reddit_title_body | 449 |
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