nils-herrmann/clean_scirepeval huggingface dataset:
A mathematical derivation of zero-temperature 2D superconductivity from microscopic Bardeen-Cooper-Schrieffer model

Starting from H. Fr\"ohlich's second-quantized Hamiltonian for a $d$-dimensional electron gas in interaction with lattice phonons describing the quantum vibrations of a metal, we present a rigorous mathematical derivation of the superconducting state, following the principles laid out originally in 1957 by J. Bardeen, L. Cooper and J. Schrieffer. As in the series of papers written on the subject in the 90es, of which the present paper is a continuation, the representation of ions as a uniform charge background allows for a $(1+d)$-dimensional fermionic quantum-field theoretic reformulation of the model at equilibrium. For simplicity, we restrict in this article to $d=2$ dimensions and zero temperature, and disregard effects due to electromagnetic interactions. Under these assumptions, we prove transition from a Fermi liquid state to a superconducting state made up of Cooper pairs of electrons at an energy level $\Gamma_{\phi}\sim \hbar\omega_D e^{-\pi/m\lambda}$ equal to the mass gap, expressed in terms of the Debye frequency $\omega_D$, electron mass $m$ and coupling constant $\lambda$. The dynamical $U(1)$-symmetry breaking produces at energies lower than the energy gap $\Gamma_{\phi}$ a Goldstone boson, a non-massive particle described by an effective $(2+1)$-dimensional non-linear sigma-model, whose parameters and correlations are computed. The proof relies on a mixture of general concepts and tools (multi-scale cluster expansions, Ward identities), adapted to this quantum many-body problem with its extended infra-red singularity located on the Fermi circle, and a specific $1/N$-expansion giving the leading diagrams at intermediate energies. Ladder diagrams are proved to provide the leading behavior in the infra-red limit, in agreement with mean-field theory predictions.

Field of study: Physics
The prevalence of DSM-III-R alcohol dependence in two American Indian populations.

Evidence suggests that American Indian (AI) populations may be at increased risk for problems with alcohol, but a lack of community-based research using diagnostic criteria has constrained our ability to draw inferences about the extent of severe alcohol problems, such as dependence, in AI populations.



This article draws on data collected by the American Indian Service Utilization, Psychiatric Epidemiology, Risk and Protective Factors Project (AI-SUPERPFP), which involved interviews with 3084 AI people living on or near their reservations. The AI-SUPERPFP sample was drawn from two culturally distinct tribes, which were designated with geographical descriptions: Northern Plains (NP) and Southwest (SW). Comparisons with data collected by the National Comorbidity Survey (NCS) were explored by using shared measures to situate the findings from AI-SUPERPFP in a national context.



Lifetime rates of DSM-III-R alcohol dependence for men in both AI-SUPERPFP samples were 50% higher than those found in the NCS. Rates of lifetime alcohol dependence for women varied by sample, however; NP women had twice the rate of women in the NCS, but SW women had rates quite similar to those of NCS women. Patterns for 12-month alcohol dependence in AI-SUPERPFP were generally more similar to those found in NCS.



The rates of DSM-III-R alcohol dependence found in AI-SUPERPFP were generally higher than US averages and justify continued attention and concern to alcohol problems in AI communities, but they are not nearly as high as those in other reports in the literature that rely on less stringent sampling methods. Furthermore, significant sociocultural influences on the correlates of alcohol dependence in AI communities are evident in these data, underscoring the need to appreciate the complex and varying influences on the patterning of alcohol problems in the diverse cultural contexts of the US.

Field of study: Medicine
Decoupled molecules with binding polynomials of bidegree (n, 2)

We present a result on the number of decoupled molecules for systems binding two different types of ligands. In the case of n and 2 binding sites respectively, we show that there are $$2(n!)^{2}$$2(n!)2 decoupled molecules to a generic binding polynomial. For molecules with more binding sites for the second ligand, we provide computational results.

Field of study: Biology, Mathematics
Doing Unto Future Selves As You Would Do Unto Others: Psychological Distance and Decision Making

Four experiments showed that the decisions people make for future selves and other people are similar to each other and different from their decisions for present selves. Experiments involved decisions to drink a disgusting liquid for scientific purposes (Experiment 1), tutor peers during exam week (Experiment 2), receive e-mails for charity (Experiment 3), and defer a lottery prize for a larger one (Experiment 4). These findings seemed to be at least partially rooted in the tendency for decisions regarding the ongoing, present self to be uniquely influenced by internal subjective experience. Specifically, these effects emerged for real, but not hypothetical, decisions. Also, they were mitigated by manipulations that altered participants' attention to present or future subjective experience. In addition, when participants' subjective experience primarily involved empathy for others (Experiment 3), their decisions on behalf of present selves were more generous than their decisions for future selves and others. Applications are discussed.

Field of study: Psychology
MO‐D‐AUD B‐07: Analysis of Rectal Dose Variability Due to Inter‐Fractional Variations of Rectal Marker Positioning in Film‐Based HDR Cervical Brachytherapy

In film‐based intracavitary brachytherapy for cervical cancer, rectal dose is usually computed using rectal markers. Position of the markers may not accurately represent the anterior rectal wall. The study is to retrospectively analyze the variability of rectal dose due to variations of marker placement in a multi‐fractionated HDR treatment regimen.  A cohort of five patients, total 18 applications, treated with multiple‐fraction tandem/ovoid HDR brachytherapy was studied. To correlate the rectal points from different fractions to the same coordinate system, the cervical os point and the orientation of the applicators were manually matched. With the applicator matching, rectal points obtained from other fractions were input into the original treatment plan for each application. A rectal dose was then calculated from all the possible rectal points. The fractional rectal doses were summed as the new cumulative rectal dose for each patient, which was compared with the original cumulative rectal dose. The reproducibility of the results was also analyzed by repeating the matching procedure.  The maximum inter‐fractional variation of distances between rectal dose points and the closest source positions was 1.1 cm and the corresponding maximum variability of fractional rectal dose was 65.5%. The percentage difference in cumulative rectal dose estimation for each patient was 5.1%, 16.4%, 25.7%, 18.9%, 12.2%, respectively. Overall reproducibility of the results was within 1.8%.  Our results show underestimation of the rectal dose caused by variations of rectal marker positioning relative to the anterior rectal wall, which should be taken into consideration in film‐based HDR cervical brachytherapy. By manually matching the rectal points into the same treatment plan, one may minimize the possibility of underestimating the rectal dose. We will also anticipate a more accurate approach for evaluating rectal doses in HDR intracavitary brachytherapy with the emerging 3‐D volume imaging based treatment planning.

Field of study: Medicine, Physics
Zur Photochemie der 1.2‐Dipyridyl‐äthene, II. Photocyclisierung zu Phenanthrolinen

Durch Photocyclisierung der 1.2-Dipyridyl-athene sind alle isomeren Phenanthroline zuganglich. Die bisher nicht bekannten Phenanthroline wurden mittels spektroskopischer Methoden identifiziert, vor allem durch die Analyse der NMR-Spektren. Die Elektronenanregungsspektren zeigen einen starken Einflus der gegenseitigen Stellung der N-Atome.

Field of study: Chemistry
A heat transfer study aiming optimization of magnetic heat exchangers of thermomagnetic motors

One prototype of a linear reciprocating thermomagnetic motor designed to work with hot water obtained from plane solar collectors as a hot source and water at room temperature as cold source has been under development. In this motor, the force element is composed of an arrangement of permanent magnets and by two plates of magnetic material having a Curie temperature midway between the temperatures of the hot and cold sources. The magnetic material plates work as motor's heat exchangers, and are shaped in form of parallelepipedal plates with internal channels. As the power to be obtained from the motor is a direct function of its operating frequency or velocity, it is important to have an optimized design of the heat exchanger channels. We report in this work the optimization procedures performed using CFD software (Computational Fluid Dynamics) aiming to maximize the heat exchangers transfer rate. The mentioned linear reciprocating motor that has been under development is not reported here. It will be presented in another work for convenience.

Field of study: Engineering
A New Estimation Method for Burnout Point Parameters of Ballistic Missile Based on Closest Distance Method

The estimation for burnout point parameters of ballistic missile has not been solved systematically. Under the condition without prior information, the paper starts from the change of motion rules caused by the changes of force before and after burnout, and uses the combination of track time cross-extrapolation and the closest distance search to estimate burnout point parameters of target. results show that the closest distance search method is evidently better than the ordinary methods.

Field of study: Computer science
Effect of Multilayer Configuration on AC Losses of Superconducting Power Transmission Cables Consisting of Narrow Coated Conductors

Superconducting power transmission cables are regarded as a key to realize the next-generation power systems with high capacity and high efficiency, and 4 mm coated conductors have been broadly used as a standard to develop such cables. Recent research shows that, comparing with standard 4 mm coated conductors, narrow 2 mm coated conductors prove to have a pronounced advantage on AC loss reduction for superconducting cables. Besides, thanks to laser cutting technique, it became possible to cut wide coated conductors into small tapes as narrow as 2 mm without considerable damage. Hence, narrow 2 mm coated conductors are attracting more and more attentions and have turned into a potential option for developing more efficient superconducting cables. So far, there have been many discussions on AC loss characteristics of the superconducting cables consisting of 4 mm coated conductors, whereas, the studies on cables comprising narrow 2 mm coated conductors are very few. This paper is to clarify the AC loss characteristics of superconducting cables consisting of narrow 2 mm coated conductors, especially to analyze the dependence of AC loss on the number of layers, with the intention of studying the effect of multilayer configuration on AC losses of such cables. A set of numerical models simulating such superconducting cables have been developed by applying 2-D FEM method. This set of models comprises 1-layer, 2-layer, 4-layer and 6-layer cables, with the former three types of cables as practical cables under development and the last one as a future option. Narrow 2 mm coated conductors with the same critical current and current distribution were selected for all the cables. Within these cables, numerical electromagnetic field analysis has been carried out for AC loss calculation and comparison.

Field of study: Physics
Short-chain chlorinated paraffins in soil, paddy seeds (Oryza sativa) and snails (Ampullariidae) in an e-waste dismantling area in China: Homologue group pattern, spatial distribution and risk assessment.

Short-chain chlorinated paraffins (SCCPs) in multi-environmental matrices are studied in Taizhou, Zhejiang Province, China, which is a notorious e-waste dismantling area. The investigated matrices consist of paddy field soil, paddy seeds (Oryza sativa, separated into hulls and rice unpolished) and apple snails (Ampullariidae, inhabiting the paddy fields). The sampling area covered a 65-km radius around the contamination center. C10 and C11 are the two predominant homologue groups in the area, accounting for about 35.7% and 33.0% of total SCCPs, respectively. SCCPs in snails and hulls are generally higher than in soil samples (30.4-530 ng/g dw), and SCCPs in hulls are approximate five times higher than in corresponding rice samples (4.90-55.1 ng/g dw). Homologue pattern analysis indicates that paddy seeds (both hull and rice) tend to accumulate relatively high volatile SCCP homologues, especially the ones with shorter carbon chain length, while snails tend to accumulate relatively high lipophilic homologues, especially the ones with more substituted chlorines. SCCPs in both paddy seeds and snails are linearly related to those in the soil. The e-waste dismantling area, which covers a radius of approximate 20 km, shows higher pollution levels for SCCPs according to their spatial distribution in four matrices. The preliminary assessment indicates that SCCP levels in local soils pose no significant ecological risk for soil dwelling organisms, but higher risks from dietary exposure of SCCPs are suspected for people living in e-waste dismantling area.

Field of study: Environmental science
Robust $$k$$k-mer frequency estimation using gapped $$k$$k-mers

Oligomers of fixed length, $$k$$k, commonly known as $$k$$k-mers, are often used as fundamental elements in the description of DNA sequence features of diverse biological function, or as intermediate elements in the constuction of more complex descriptors of sequence features such as position weight matrices. $$k$$k-mers are very useful as general sequence features because they constitute a complete and unbiased feature set, and do not require parameterization based on incomplete knowledge of biological mechanisms. However, a fundamental limitation in the use of $$k$$k-mers as sequence features is that as $$k$$k is increased, larger spatial correlations in DNA sequence elements can be described, but the frequency of observing any specific $$k$$k-mer becomes very small, and rapidly approaches a sparse matrix of binary counts. Thus any statistical learning approach using $$k$$k-mers will be susceptible to noisy estimation of $$k$$k-mer frequencies once $$k$$k becomes large. Because all molecular DNA interactions have limited spatial extent, gapped $$k$$k-mers often carry the relevant biological signal. Here we use gapped $$k$$k-mer counts to more robustly estimate the ungapped $$k$$k-mer frequencies, by deriving an equation for the minimum norm estimate of $$k$$k-mer frequencies given an observed set of gapped $$k$$k-mer frequencies. We demonstrate that this approach provides a more accurate estimate of the $$k$$k-mer frequencies in real biological sequences using a sample of CTCF binding sites in the human genome.

Field of study: Biology, Mathematics
A QUANTIFICATION METHOD OF STRUCTURAL ROBUSTNESS

Structural robustness requires that the structure is capable of resisting disproportionate collapse.How to evaluate the structural robustness quantitatively is one of the most challenging problems in structural engineering.From the structural bearing capacity,the paper proposes a new method to calculate the importance coefficients of components.And then according to the importance coefficient,a new indicator of structural robustness and a new method to evaluate it are presented.Therefore,the quantization of structural robustness has been realized.The method for quantizing structural robustness is illustrated in examples which use plane truss structures and plane frame structures.The computation result implies that the ranking of the robustness indicators of 4 plane frame structures which have the same width and height is consistent with the result of the qualitative analysis,showing the rationality of the proposed robustness indicator.At last,through comparing and analyzing the robustness indicators of the 4 frame structures,some factors that affect the structural robustness are obtained,including load type,span uniformity,total span number and brace.

Field of study: Engineering
Exact critical points for the analysis of means

Tables of the exact critical points for the analysis of means are given for k means with degrees of freedom m and level of significance a for k = 3(1)20, 24, 30, 40, 60 m = k(l)20, 24, 30, 40, 60, 120, ∞ α = 0.10, 0.05, 0.01.

Field of study: Mathematics
Mercury in fish from three rift valley lakes (Turkana, Naivasha and Baringo), Kenya, East Africa.

Total mercury (THg) concentrations were measured for various fish species from Lakes Turkana, Naivasha and Baringo in the rift valley of Kenya. The highest THg concentration (636 ng g(-1) wet weight) was measured for a piscivorous tigerfish Hydrocynus forskahlii from Lake Turkana. THg concentrations for the Perciformes species, the Nile perch Lates niloticus from Lake Turkana and the largemouth bass Micropterus salmoides from Lake Naivasha ranged between 4 and 95 ng g(-1). The tilapiine species in all lakes, including the Nile tilapia Oreochromis niloticus, had consistently low THg concentrations ranging between 2 and 25 ng g(-1). In Lake Naivasha, the crayfish species, Procambrus clarkii, had THg concentrations similar to those for the tilapiine species from the same lake, which is consistent with their shared detritivore diet. THg concentrations in all fish species were usually consistent with their known trophic position, with highest concentrations in piscivores and declining in omnivores, insectivores and detritivores. One exception is the detritivore Labeo cylindricus from Lake Baringo, which had surprisingly elevated THg concentrations (mean=75 ng g(-1)), which was similar to those for the top trophic species (Clarias and Protopterus) in the same lake. Except for two Hydrocynus forskahlii individuals from Lake Turkana, which had THg concentrations near or above the international marketing limit of 500 ng g(-1), THg concentrations in the fish were generally below those of World Health Organization's recommended limit of 200 ng g(-1) for at-risk groups.

Field of study: Environmental science
Magneto-optical and optical properties of polycrystalline Со–Р films with nanometer thickness

Features of the optical and magneto-optical properties of polycrystalline Со–Р films with nanometer thickness are established experimentally. It is found that the spectra of optical parameters n and k and magnetic circular dichroism depend largely on film thickness, suggesting that magneto-optical activity is governed by different mechanisms in thin films and bulk materials.

Field of study: Physics
Xanthophylls as precursors of retinoids

Xanthophylls such as canthaxanthin, astaxanthin, zeaxanthin, lutein and tunaxanthin that are widely distributed in Nature have been found to be precursors of retinoids not only in freshwater fish and marine fish (yellowtail) but also in mammals (rat). Reductive metabolic pathways from 3-dehydroretinol to retinol and from 3-dehydroretinal to retinal have been newly discovered by feeding experiments with rat and yellowtail, respectively.

Field of study: Chemistry
Adaptation versus migration in demographically unstable populations

We analyze a model of the joint population and evolutionary dynamics of a diploid “island” population that receives a recurrent influx of immigrants from a hypothetical continent population. We derive a criterion for the initial spread of a rare allele when the island population dynamics initially are chaotic. By computing a Liapunov exponent, we show that this criterion depends on a generalization of the geometric mean absolute fitness of individuals heterozygous for the rare allele. This criterion applies regardless of whether the initial population is self-sustaining or not.

Field of study: Biology, Mathematics
Instructional Guidance and Realism of Manipulatives Influence Preschool Children's Mathematics Learning

Educators often use manipulatives when teaching mathematics because manipulatives are assumed to promote learning. However, research indicates that instructional variables impact the effectiveness of manipulatives. In this article, the authors consider the relations between two instructional characteristics: (a) level of instructional guidance and (b) perceptual qualities of manipulatives. Results from the randomized experiment with preschoolers (N = 72) suggest that learning is improved when instruction is conducted with high levels of instructional guidance and is impacted by the perceptual qualities of manipulatives. Perceptually rich manipulatives decreased learner performance on outcomes associated with conceptual knowledge and improved performance on transfer of learning. In addition, transfer was positively affected by perceptually rich manipulatives when low levels of instructional guidance were present.

Field of study: Education
Hydrogen peroxide mobilizes Ca2+ through two distinct mechanisms in rat hepatocytes

Hydrogen peroxide (H2O2) is produced during liver transplantation. Ischemia/reperfusion induces oxidation and causes intracellular Ca2+ overload, which harms liver cells. Our goal was to determine the precise mechanisms of these processes.Hepatocytes were extracted from rats. Intracellular Ca2+ concentrations ([Ca2+]i), inner mitochondrial membrane potentials and NAD(P)H levels were measured using fluorescence imaging. Phospholipase C (PLC) activity was detected using exogenous PIP2. ATP concentrations were measured using the luciferin-luciferase method. Patch-clamp recordings were performed to evaluate membrane currents.H2O2 increased intracellular Ca2+ concentrations ([Ca2+]i) across two kinetic phases. A low concentration (400 μmol/L) of H2O2 induced a sustained elevation of [Ca2+]i that was reversed by removing extracellular Ca2+. H2O2 increased membrane currents consistent with intracellular ATP concentrations. The non-selective ATP-sensitive cation channel blocker amiloride inhibited H2O2-induced membrane current increases and [Ca2+]i elevation. A high concentration (1 mmol/L) of H2O2 induced an additional transient elevation of [Ca2+]i, which was abolished by the specific PLC blocker U73122 but was not eliminated by removal of extracellular Ca2+. PLC activity was increased by 1 mmol/L H2O2 but not by 400 μmol/L H2O2.Conclusion:H2O2 mobilizes Ca2+ through two distinct mechanisms. In one, 400 μmol/L H2O2-induced sustained [Ca2+]i elevation is mediated via a Ca2+ influx mechanism, under which H2O2 impairs mitochondrial function via oxidative stress, reduces intracellular ATP production, and in turn opens ATP-sensitive, non-specific cation channels, leading to Ca2+ influx. In contrast, 1 mmol/L H2O2-induced transient elevation of [Ca2+]i is mediated via activation of the PLC signaling pathway and subsequently, by mobilization of Ca2+ from intracellular Ca2+ stores.

Field of study: Biology, Chemistry, Medicine
Isolation and characterization of two monoclonal antibodies raised against tms1 protein of fission yeast.

Monoclonal antibodies were produced against recombinant tms1 protein of fission yeast. The antibodies of IgG3 subclass were isolated from serum-free cell culture medium and purified by affinity chromatography on protein A-Sepharose. The antibodies can be used to detect specifically the tms1 protein on immunoblots of total yeast lysates. In addition, native tms1 protein is specifically precipitated by these antibodies from yeast lysates.

Field of study: Biology