nils-herrmann/clean_scirepeval huggingface dataset:
Structural basis of the transactivation deficiency of the human PPARγ F360L mutant associated with familial partial lipodystrophy.

The peroxisome proliferator-activated receptors (PPARs) are transcription factors that regulate glucose and lipid metabolism. The role of PPARs in several chronic diseases such as type 2 diabetes, obesity and atherosclerosis is well known and, for this reason, they are the targets of antidiabetic and hypolipidaemic drugs. In the last decade, some rare mutations in human PPARγ that might be associated with partial lipodystrophy, dyslipidaemia, insulin resistance and colon cancer have emerged. In particular, the F360L mutant of PPARγ (PPARγ2 residue 388), which is associated with familial partial lipodystrophy, significantly decreases basal transcriptional activity and impairs stimulation by synthetic ligands. To date, the structural reason for this defective behaviour is unclear. Therefore, the crystal structure of PPARγ F360L together with the partial agonist LT175 has been solved and the mutant has been characterized by circular-dichroism spectroscopy (CD) in order to compare its thermal stability with that of the wild-type receptor. The X-ray analysis showed that the mutation induces dramatic conformational changes in the C-terminal part of the receptor ligand-binding domain (LBD) owing to the loss of van der Waals interactions made by the Phe360 residue in the wild type and an important salt bridge made by Arg357, with consequent rearrangement of loop 11/12 and the activation function helix 12 (H12). The increased mobility of H12 makes the binding of co-activators in the hydrophobic cleft less efficient, thereby markedly lowering the transactivation activity. The spectroscopic analysis in solution and molecular-dynamics (MD) simulations provided results which were in agreement and consistent with the mutant conformational changes observed by X-ray analysis. Moreover, to evaluate the importance of the salt bridge made by Arg357, the crystal structure of the PPARγ R357A mutant in complex with the agonist rosiglitazone has been solved.

Field of study: Chemistry
Elastic and plastic contributions to X-ray Line broadening of InGaAsP/InP Heterostructures

The coherency state of MOCVD grown InGaAsP/InP double-heterostructure wafers was examined and their effects on the structural properties were determined in this study. Lattice mismatches were measured using {511} asymmetric and (400) symmetric x-ray reflections. The chemical lattice misfit and the elastic strain were also calculated. Misfit dislocations were examined by both x-ray topography and photoluminescence imaging. The x-ray full width at half maximum (FWHM) varied with the degree of mismatch. The largest FWHM was obtained for samples containing the misfit dislocations. It was found that FWHM is influenced not only by the plastic deformation, but also by the elastic strain. To model the dependence of the FWHM, the radius of curvature was measured, and its contribution to the x-ray line broadening was calculated. Also, the contribution from misfit dislocations was taken into account. This model assumes that the dislocations are planar and interact weakly with each other. Good agreement between measured and calculated values was obtained. Thus, it is concluded that the major contribution to x-ray line broadening ofelastically strained sample is the lattice curvature induced by misfit strain, and that the dominant factor affecting x-ray FWHM ofplastically deformed sample is lattice relaxation induced by misfit dislocation.

Field of study: Materials science
Clay mineralogical constraints on weathering in response to early Eocene hyperthermal events in the Bighorn Basin, Wyoming (Western Interior, USA)

Series of transient greenhouse warming intervals in the early Eocene provide an opportunity to study the response of rock weathering and erosion to changes in temperature and precipitation. During greenhouse warming, chemical weathering is thought to increase the uptake of carbon from the atmosphere, while physical weathering and erosion control sediment supply. A large ancient greenhouse warming event is the Paleocene-Eocene Thermal Maximum at 56 Ma. In many coastal sites, an increase in the abundance of kaolinite clay during the Paleocene-Eocene Thermal Maximum is interpreted as the result of reworking from terrestrial strata due to enhanced runoff caused by increased seasonal precipitation and storminess during a time of decreased vegetation cover. In the continental interior of North America, Eocene Thermal Maximum paleosols show more intense pedogenesis and drying, which are indicated by deeply weathered and strongly oxidized soil profiles. The weathering and oxidation could be related to temperature and precipitation changes, but also to increased time available for weathering and increased soil permeability in coarser sediment. 
Here, we provide evidence for enhanced climate seasonality, increased erosion of proximal laterites and intrabasinal floodplain soils, and a potential slight increase in chemical weathering during the smaller early Eocene hyperthermals (Eocene Thermal Maximum 2, including H1 and H2) postdating the Paleocene-Eocene Thermal Maximum, for which no previous clay mineral data were available. Hyperthermal soil formation at the site of floodplain deposition causes a similar, insignificant clay mineralogical change as occurred during the background climates of the early Eocene by showing small increases in smectite and decreases in illite-smectite and illite. Remarkably, the detrital sediments during the hyperthermals show a similar pedogenic-like increase of smectite and decreases of mixed-layer illite-smectite and illite, while the kaolinite and chlorite proportions remained low and unchanged. Since sedimentation rates and provenance were similar during the events, enhanced smectite neoformation during soil formation in more proximal settings, and associated reworking, is the likely process causing this clay mineralogical change. The hundreds to thousands of year time scales at which individual paleosols were formed were probably too short for significant alteration of the rocks by in situ chemical weathering despite changing climates during the two post−Paleocene-Eocene Thermal Maximum greenhouse warming episodes. The relatively small signal, however, raises the question of whether increased chemical weathering can indeed be a strong negative feedback mechanism to enhanced greenhouse gas warming over the time scales at which these processes act.

Field of study: Geology
Microscopic Theory of Nuclear Fission

We describe the fission dynamics of $^{240}$Pu within an implementation of the Density Functional Theory (DFT) extended to superfluid systems and real-time dynamics. We demonstrate the critical role played by the pairing correlations, which even though are not the driving force in this complex dynamics, are providing the essential lubricant, without which the nuclear shape evolution would come to a screeching halt. The evolution is found to be much slower than previously expected in this fully non-adiabatic treatment of nuclear dynamics, where there are no symmetry restrictions and all collective degrees of freedom (CDOF) are allowed to participate in the dynamics.

Field of study: Physics
Drinking in a patchy environment: the effect of the price of water.

Rats in a laboratory foraging paradigm searched for sequential opportunities to drink in two water patches that differed in the bar-press price of each "sip" (20 licks) of water within a bout of drinking (Experiment 1) or the price and size (10, 20, or 40 licks) of each sip (Experiment 2). Total daily water intake was not affected by these variables. The rats responded faster at the patch where water was more costly. However, they accepted fewer opportunities to drink, and thus had fewer drinking bouts, and drinking bouts were smaller at the more costly patch than at the other patch. This resulted in the rats consuming a smaller proportion of their daily water from the more costly patch. The size of the differences in bout frequency and size between the patches appears to be based on the relative cost of water at the patches. The profitability of each patch was calculated in terms of the return (in milliliters) on either effort (bar presses) or time spent there. Although both measures were correlated with the relative total intake, bout size, and acceptance of opportunities at each patch, the time-based profitability was the better predictor of these intake measures. The rats did not minimize bar-press output; however, their choice between the patches and their bout sizes within patches varied in a way that reduced costs compared to what would have been expended drinking randomly. These data accord well with similar findings for choices among patches of food, suggesting that foraging for water and food occurs on the basis of comparable benefit-cost functions: In each case, the amount consumed is related to the time spent consuming.

Field of study: Biology, Psychology
Foundry Technique of Large Sized Speed Governor Planet Carrier Ductile Iron Casting for Wind Power Generator

The article resumes one kind of casting technique about the defects of porosity and shrinks during the productive process of the planet frame of wind power governor of large nodular iron castings,analyzes the causes of the defects,introduces some main techniques and measures to remove the defects,such as optimal designs of feed system,improvements of riser system,optimal setups of cold iron and improvements of feed technique,etc.

Field of study: Materials science
Appraisal-Coping Goodness of Fit: A Daily Internet Study

Using an Internet daily diary methodology, this study tested the goodness of fit hypothesis, which highlights the importance of the match between controllability appraisals and coping efforts in adjustment to stressful events. For 28 days, 190 undergraduates described their most stressful event and its controllability, how they coped, and their daily positive and negative mood. Individuals demonstrated fit across situations, with control appraisals associated positively with problem-focused coping and negatively with emotional approach coping and avoidance coping. A pooled within-person interaction indicated that problem-focused coping had a stronger positive association with positive mood when dealing with high versus low control stressors. Significant variation also was found in several other within-person interactions between control appraisals and coping, and some evidence was found for the notion that individual differences in the degree of matching coping to control appraisals were associated with person-level adjustment.

Field of study: Psychology
Investigation on a new silver photoimageable conductor

A new thick film photoimageable silver paste of improved properties has been elaborated. The paste is less sensitive to the visible light. Certain disadvantages of most commercially available materials, such as necessity of operating with the paste in the room illuminating with yellow, green or red light has been eliminated. Further improvement of conductive silver pastes to enable reducing lines width down to 10 μm has been done.

Field of study: Engineering
SANITATION AND HYGIENE FACILITIES ARE ESSENTIAL FOR ACHIEVEMENT OF GOOD HEALTH

‘Clean India: Clean Environment’. A key feature of the campaign is to ensure that every locality either in rural or urban in India has a set of functioning and well maintained water, sanitation and hygiene facilities.Sanitation is essential for achievementof health and promotion of human dignity. Improved sanitation is a basic human right. Exposure to faecal pathogens including rotavirus,pathogenic strains of Escherichia coli, Vibrio cholerae, Shigellaspp, and Salmonellaenterica serotype Typhi, hepatitisE virus, and soil-transmitted helminths can precipitate serious human illness.So necessary efforts have to be taken to reduce exposure to human faeces through improvement of sanitation particularly in low-income communities and rural population for the improvement of health.  Therelative importance of sanitation in the interruption of pathogen transmission almost certainly varies bycommunity. In some communities, water contaminated from a distant source; food contaminated in agricultural fields, in markets, or during commercial preparation; or hands contaminated through cleaning up of children who defecated, handling of animal manure, or contact with contaminated food are likely prominent pathways of enteric pathogen transmission that would be immediately interrupted by improvements in household sanitary infrastructure of clinical management.

Field of study: Medicine
Overcoming the false-minima problem in direct methods: structure determination of the packaging enzyme P4 from bacteriophage phi13.

The problems encountered during the phasing and structure determination of the packaging enzyme P4 from bacteriophage phi13 using the anomalous signal from selenium in a single-wavelength anomalous dispersion experiment (SAD) are described. The oligomeric state of P4 in the virus is a hexamer (with sixfold rotational symmetry) and it crystallizes in space group C2, with four hexamers in the crystallographic asymmetric unit. Current state-of-the-art ab initio phasing software yielded solutions consisting of 96 atoms arranged as sixfold symmetric clusters of Se atoms. However, although these solutions showed high correlation coefficients indicative that the substructure had been solved, the resulting phases produced uninterpretable electron-density maps. Only after further analysis were correct solutions found (also of 96 atoms), leading to the eventual identification of the positions of 120 Se atoms. Here, it is demonstrated how the difficulties in finding a correct phase solution arise from an intricate false-minima problem.

Field of study: Chemistry
Strontium isotopic composition of Pliocene and Pleistocene molluscs from emerged marine deposits, North American Arctic

High-precision strontium (Sr) isotopic measurements were obtained for 53 Pliocene and Pleistocene molluscan shells from emerged marine deposits around the coasts of Arctic North America to test whether such data can be used for chronostratigraphic purposes. 87Sr/86Sr ratios from Sr isotopic measurements on many marine fossils from Arctic Ocean borderland sites are broadly consistent with their expected values based on independent age control and on a comparison with the Sr isotopic evolution of seawater recorded in deep-sea cores. All 87Sr/86Sr ratios measured for shells from Middle and Late Pleistocene deposits are consistent with expected values, but only 9 of 22 ratios in shells from older deposits are consistent with independent age estimates. Aberrant 87Sr/86Sr ratios are consistently higher than expected. At Nome, Alaska, and Baffin Island, Canada, all 87Sr/86Sr ratios are higher than expected. Because these shells were formed along the Pacific Ocean and Atlantic Ocean margins, respectively, their h...

Field of study: Environmental science
The effects of increased atmospheric carbon dioxide and temperature on carbon partitioning, source‐sink relations and respiration

Herbaceous C3 plants grown in elevated CO2 show increases in carbon assimilation and carbohydrate accumulation (particularly starch) within source leaves. Although changes in the partitioning of biomass between root and shoot occur, the proportion of this extra assimilate made available for sink growth is not known. Root:shoot ratios tend to increase for CO2-enriched herbaceous plants and decrease for CO2-enriched trees. Root:shoot ratios for cereals tend to remain constant. In contrast, elevated temperatures decrease carbohydrate accumulation within source and sink regions of a plant and decrease root:shoot ratios. Allometric analysis of at least two species showing changes in root: shoot ratios due to elevated CO2 show no alteration in the whole-plant partitioning of biomass. Little information is available for interactions between temperature and CO2. Cold-adapted plants show little response to elevated levels of CO2, with some species showing a decline in biomass accumulation. In general though, increasing temperature will increase sucrose synthesis, transport and utilization for CO2-enriched plants and decrease carbohydrate accumulation within the leaf. Literature reports are discussed in relation to the hypothesis that sucrose is a major factor in the control of plant carbon partitioning. A model is presented in support.

Field of study: Environmental science
Distributed Broadcast Channel Access

This paper presents a general approach to sharing a broadcast channel among multiple processors. There are two components to the problem of sharing a single resource: (1) How to specify the usage pattern of the resource; and (2) How to restrict access to the resource so that the specified usage pattern can be realized. One way to solve both of these problems is solved by embodying the desired usage pattern in priority update algorithms which assign unique priorities to all the users. The secobd problem then becomes that of determining the competing user who has the highest priority when the resource is free. Solutions are proposed which promise the combined advantages of ethernet (short message delay) and ringnet (high throughput).

Field of study: Computer science
Modular Versus Monoblock Hemiarthroplasty in Trauma: A 5-Year Retrospective Analysis of Radiographic and Clinical Outcomes

Displaced intraarticular neck of femur fractures for low-demand patients are primarily managed with hemiarthroplasty. The optimal implant design for modularity is unclear. Globally and within Australia, the use of monoblock implants varies significantly by location; however, monoblock use is decreasing in Australia in favour of modular systems, with little evidence-based explanation. This study aimed to compare the radiological and clinical outcomes of monoblock and modular hemiarthroplasties.

Field of study: Medicine
Monetary taxation in a monetary exchange economy

We study monetary taxation in an intertemporal general equilibrium model with price-tax uncertainty. Ad valorem taxation is introduced into a fully monetarized temporary equilibrium system which admits barter and monetary exchange. The tax system is sufficiently flexible to allow for a variety of taxation schemes and policies, both within and between periods. The proof of the existence of a competitive price-tax equilibrium constitutes a departure point for the rigorous study of fiscal policy in a dynamic framework.

Field of study: Economics
THE INTRINSIC QUASAR LUMINOSITY FUNCTION: ACCOUNTING FOR ACCRETION DISK ANISOTROPY

Quasar luminosity functions are a fundamental probe of the growth and evolution of supermassive black holes. Measuring the intrinsic luminosity function is difficult in practice, due to a multitude of observational and systematic effects. As sample sizes increase and measurement errors drop, characterizing the systematic effects is becoming more important. It is well known that the continuum emission from the accretion disk of quasars is anisotropic—in part due to its disk-like structure—but current luminosity function calculations effectively assume isotropy over the range of unobscured lines of sight. Here, we provide the first steps in characterizing the effect of random quasar orientations and simple models of anisotropy on observed luminosity functions. We find that the effect of orientation is not insignificant and exceeds other potential corrections such as those from gravitational lensing of foreground structures. We argue that current observational constraints may overestimate the intrinsic luminosity function by as much as a factor of ~2 on the bright end. This has implications for models of quasars and their role in the universe, such as quasars' contribution to cosmological backgrounds.

Field of study: Physics
Explosive Consolidation of (Bi, Pb)-Sr-Ca-Cu-0 Superconductor Powders

Superconducting (2212 phase) Bi-Sr-Ca-Cu-0 (BSCCO) and BSCCO-Ag composites were explosively consolidated in silver tubing and then drawn and rolled into tapes. These silver-sheathed tapes were then subjected to repeated cycles of pressing and heat treatment, which resulted in enhanced texturing and grain growth and a subsequent increase in critical current density (Jc). The effect of Ag powder additions to the superconducting powder further increased texturing and Jc, with optimal properties occurring with 10 vol.% silver powder additions. Scanning electron microscopy indicated that grain alignment increased and grain structure became refined after the thermomechanical treatment. X-ray diffraction studies indicated that grain orientation and conversion of 2212 phase to 2223 phase are improved when explosive consolidation is introduced before the drawing step in the powder-in-tube process.

Field of study: Materials science
A C(K) Banach space which does not have the Schroeder-Bernstein property

We construct a totally disconnected compact Hausdorff space N which has clopen subsets M included in L included in N such that N is homeomorphic to M and hence C(N) is isometric as a Banach space to C(M) but C(N) is not isomorphic to C(L). This gives two nonisomorphic Banach spaces of the form C(K) which are isomorphic to complemented subspaces of each other (even in the above strong isometric sense), providing a solution to the Schroeder-Bernstein problem for Banach spaces of the form C(K). N is obtained as a particular compactification of the pairwise disjoint union of a sequence of Ks for which C(K)s have few operators.

Field of study: Mathematics