nils-herrmann/clean_scirepeval huggingface dataset:
Crystal structure of the novel amino-acid racemase isoleucine 2-epimerase from Lactobacillus buchneri.

Crystal structures of Lactobacillus buchneri isoleucine 2-epimerase, a novel branched-chain amino-acid racemase, were determined for the enzyme in the apo form, in complex with pyridoxal 5'-phosphate (PLP), in complex with N-(5'-phosphopyridoxyl)-L-isoleucine (PLP-L-Ile) and in complex with N-(5'-phosphopyridoxyl)-D-allo-isoleucine (PLP-D-allo-Ile) at resolutions of 2.77, 1.94, 2.65 and 2.12 Å, respectively. The enzyme assembled as a tetramer, with each subunit being composed of N-terminal, C-terminal and large PLP-binding domains. The active-site cavity in the apo structure was much more solvent-accessible than that in the PLP-bound structure. This indicates that a marked structural change occurs around the active site upon binding of PLP that provides a solvent-inaccessible environment for the enzymatic reaction. The main-chain coordinates of the L. buchneri isoleucine 2-epimerase monomer showed a notable similarity to those of α-amino-ℇ-caprolactam racemase from Achromobactor obae and γ-aminobutyrate aminotransferase from Escherichia coli. However, the amino-acid residues involved in substrate binding in those two enzymes are only partially conserved in L. buchneri isoleucine 2-epimerase, which may account for the differences in substrate recognition by the three enzymes. The structures bound with reaction-intermediate analogues (PLP-L-Ile and PLP-D-allo-Ile) and site-directed mutagenesis suggest that L-isoleucine epimerization proceeds through abstraction of the α-hydrogen of the substrate by Lys280, while Asp222 serves as the catalytic residue adding an α-hydrogen to the quinonoid intermediate to form D-allo-isoleucine.

Field of study: Chemistry
Opening Closed Minds: The Combined Effects of Intergroup Contact and Need for Closure on Prejudice

Five studies tested whether need for closure (NFC) moderates the relation between intergroup contact and prejudice toward immigrants. The results consistently showed that intergroup contact was more strongly associated with reduced levels of prejudice among people high in NFC compared to people low in NFC. Studies 1 (N = 138 students) and 2 (N = 294 adults) demonstrated this moderator effect on subtle, modern, and blatant racism. Study 2 also replicated the moderator effect for extended contact. An experimental field study (Study 3; N = 60 students) provided evidence of the causal direction of the moderator effect. Finally, Studies 4 (N = 125 students) and 5 (N = 135 adults) identified intergroup anxiety as the mediator through which the moderator effect influences modern and blatant racism as well as hostile tendencies toward immigrants. The role of motivated cognition in the relation between intergroup contact and prejudice is discussed.

Field of study: Psychology
State Reform during the Provisional Presidency: Chihuahua, 1911

rTI HE ANTI-REEELECTIONIST movement of Francisco I. Madero won political power in 1911 by defeating the dictatorship of Porfirio Diaz in the first of a series of rebellions and civil wars collectively known as the Mexican Revolution. Beyond seizing national authority, Madero's achievements were limited. After his victory he turned over political authority to a caretaker government until national presidential elections could be held which would give him a constitutional basis for power. This decision handicapped the accomplishment of his modest political reforms. During the interim presidency of Francisco Leon de la Barra Madero 's revolutionary movement began to come apart, while the previous Porfirian bureaucracy remained unchallenged. Upon assuming the presidency Madero was unable to cope with conservative hostility and revolutionary disaffection, which finally brought about the collapse of his government and his assassination in February 1913. Lack of perspicacity and unpolitic decisions characterized his national administration. But while national developments may account for his failure, they tend to obscure the dynamics of the Madero Revolution. By reasserting the federalist structure of the Constitution of 1857 and temporarily withdrawing from national authority, Madero provided an opportunity for state administrations to initiate reform programs during the provisional presidency. As a case study, the gubernatorial regime in Chihuahua illustrates the dramatic developments of the revolutionary movement in one state from the resignation of Porfirio Diaz until the inauguration of Madero as president. In November 1911 Madero appointed Abraham Gonzalez provisional goovernor of his native state.' Gonzalez had been an

Field of study: History
Validating strategic alignment of organizational IT requirements using goal modeling and problem diagrams

Ensuring that organizational IT is in alignment with and provides support for an organization's business strategy is critical to business success. We present an integrated approach to requirements engineering for organizational IT. To help validate IT-business strategy alignment, we propose a single model according to Jackson's problem diagram framework to encompass both business strategy and system requirements. We use an organizational strategy analysis technique to deconstruct business strategy. Strategy is then modeled using a goal-oriented requirements engineering notation; a framework for modeling an organization's business strategy proposed by the Business Rules Group is used to construct the goal model. We use Jackson's context diagrams to represent both business and IT domain context. Our approach is illustrated via application to an exemplar, constructed from a variety of sources in the literature describing Seven-Eleven Japan.

Field of study: Computer science, Engineering
The Inductrack: a simpler approach to magnetic levitation

Arising out of research at the Lawrence Livermore National Laboratory on passive magnetic bearings, a new magnetic levitation system, the Inductrack, has been developed and tested at model scale. The system employs special arrays of permanent magnets (Halbach arrays) on the moving car. The magnetic field from the arrays induces repelling currents in a close-packed array of shorted circuits in the track. Above a low transition speed (a few kilometers per hour), levitation forces approach a constant value, while drag forces decrease inversely with speed, with L/D reaching 200:1 or more at operating speeds. The high magnetic efficiency of the Halbach arrays, plus the use of close-packed track circuits, results in levitating forces approaching 40 metric tonnes per square meter (using NdFeB permanent magnet arrays, whose weight in typical cases is a few percent of the levitated weight). The system is passively stable: only motion is required for levitation. Failure of the drive system only results in the train slowing down and settling onto auxiliary wheels at a low speed. A detailed theoretical analysis of the Inductrack was made, on the basis of which a small-scale model was constructed and operated. The Laboratory is building a new small-scale model system (under NASA sponsorship) to demonstrate the acceleration rates and speeds (10-g and Mach 0.4 in the model) needed to magnetically launch rockets.

Field of study: Physics
Creep, stress relaxation, and plastic deformation in Sn-Ag and Sn-Zn eutectic solders

Because of the high homologous operation temperature of solders used in electronic devices, time and temperature dependent relaxation and creep processes affect their mechanical behavior. In this paper, two eutectic lead-free solders (96.5Sn-3.5Ag and 91Sn-9Zn) are investigated for their creep and stress relaxation behavior. The creep tests were done in load-control with initial stresses in the range of 10-22 MPa at two temperatures, 25 and 80°C. The stress relaxation tests were performed under constant-strain conditions with strains in the range of 0.3-2.4% and at 25 and 80°C. Since creep/relaxation processes are active even during monotonie tensile tests at ambient temperatures, stress-strain curves at different temperatures and strain rates provide insight into these processes. Activation energies obtained from the monotonic tensile, stress relaxation, and creep tests are compared and discussed in light of the governing mechanisms. These data along with creep exponents, strain rate sensitivities and damage mechanisms are useful for aiding the modeling of solder interconnects for reliability and lifetime prediction. Constitutive modeling for creep and stress relaxation behavior was done using a formulation based on unified creep plasticity theory which has been previously employed in the modeling of high temperature superalloys with satisfactory results.

Field of study: Materials science
Wake-promoting actions of medial basal forebrain beta2 receptor stimulation.

The locus coeruleus-noradrenergic system exerts an activating influence on forebrain neuronal and behavioral activity states, in part, through the actions of noradrenergic beta receptors located within the medial septal (MS) and medial preoptic (MPOA) areas. The current study examined the extent to which beta2 receptors located within these medial basal forebrain regions modulate behavioral state. In this study, the sleep-wake effects of microinfusion of the beta2 agonist, clenbuterol, into the MS and MPOA were examined. Clenbuterol infusion into both MS and MPOA elicited a dose-dependent increase in time spent awake. These observations indicate that medial basal forebrain beta-sub-2 receptors participate in the noradrenergic-dependent modulation of behavioral state.

Field of study: Biology, Psychology
Query-Complexity Amplification for Random Oracles

Increasing the computational complexity of evaluating a hash function, both for the honest users as well as for an adversary, is a useful technique employed for example in password-based cryptographic schemes to impede brute-force attacks, and also in so-called proofs of work (used in protocols like Bitcoin) to show that a certain amount of computation was performed by a legitimate user. A natural approach to adjust the complexity of a hash function is to iterate it c times, for some parameter c, in the hope that any query to the scheme requires c evaluations of the underlying hash function. However, results by Dodis et al. (Crypto 2012) imply that plain iteration falls short of achieving this goal, and designing schemes which provably have such a desirable property remained an open problem.

Field of study: Computer science, Mathematics
Identification of a panel of cytokines in neonates with hypoxic ischemic encephalopathy treated with hypothermia

Inflammation is a crucial but understudied mechanism of neuronal injury after hypoxia‐ischemia. The aim was to identify a panel of cytokines involved in brain injury in neonates with hypoxic ischemic encephalopathy (HIE).  Ten newborns with HIE undergoing to therapeutic hypothermia (TH, HIE Group) and 8 healthy newborns (CTRL Group) were enrolled. For the HIE group, 5 samples were collected: between 0 and 6 h of life (time 1), 12 h (time 2), 24 h (time 3), 48 h (time 4) and 96 h of life (time 5). For the CTRL group, one sample was collected. A panel of 48 inflammatory cytokines was determined in all samples. Data were analyzed using multivariate statistical analysis (Principal component analysis, PCA) Results 17 cytokines, among 48 analyzed, were found to be significantly different, initially, between the CTRL and HIE groups: 12 with reported pro‐inflammatory effects and 5 with reported anti‐inflammatory effects. In the HIE group cytokines showed a decreasing trend during the TH and at the end of treatment comparable to the CTRL group. IL‐18 did demonstrate a slight increase at time 3 during HT but decreased steadily at sampling times, 4 and 5.  Our data demonstrates that many pathways of the inflammatory cascade are activated following hypoxic‐ischemic injury. This information will increase our understanding of changes in cytokines over time in neonates with HIE undergoing TH.

Field of study: Medicine
Technology of Rapid Assay for Water Toxicity and Its Development Trends

Information of water pollution can be timely provided by rapidly detecting water toxicity, which is the basis of dealing with pollution incidents and the warning system of water quality.Rapid assays for water toxicity are mainly based on luminescent bacteria, chemical luminescence, respiration inhibition, photosynthesis decrease and electrochemical detection technology.In the present paper, it was reviewed that the main principle and technology of rapid assays for water toxicity and its development trends.

Field of study: Environmental science
Predictability of Instructional Quality on Teacher Effectiveness in The Preparation of Teachers at The College of Distance Education University of Cape Coast

The purpose of the study was to examine the predictability of instructional quality on trainee-teacher effectiveness in the delivery of Distance Education (DE) in Ghana, focusing on College of Distance Education, University of Cape Coast (CoDE, UCC).  The descriptive survey design was adopted with a quantitative approach. Total population involving 1,837 CoDE course tutors and all CoDE students at 76 study centres offering education programmes totaling 51,456 were used. The sample size for the study was 726, made up of 397 trainee-teachers and 329 course tutors. The proportionate stratified random sampling approach was employed to select respondents who completed the questionnaire instruments. The statistical analysis software tool known as the PASW Version 21.0, the Test Analysis for Surveys (TAFS) was used for analysing the data. Data on the research question was analysed using linear multiple regression analysis.  The results revealed that pedagogical quality and quality evaluation were the dimensions of instructional quality that most significantly predicted trainee-teacher effectiveness. Again, whenever trainee-teachers demonstrate high level of competence in terms of subject matter knowledge, lesson presentation skills, class management and control and lesson note preparation, they increase the extent to which their level of teaching meets pre-specified standards and goals of the college. Unique contribution to theory, practice and policy: It was recommended that management of CoDE, UCC should put in place appropriate support services in all the study centres to guide both tutors and students on appropriate instructional behaviour

Field of study: Education
Complications of spine surgery.

Over the past 2 decades, we have seen an exponential increase in the number of spine surgeries3–5 as a result of an expanding elderly population and explosion of technical innovations. During the period from 1990 to 2001, there was a greater than 220% increase in the number of spine fusions performed for degenerative spine diseases.3 In fact, the rate of spine fusion rose more rapidly in patients older than 60 years than in any other age group,3,4 with a 15-fold increase in the number of complex spine surgeries for elderly patients with spinal stenosis.4 Several clinical studies have shown that complications are greater with the increasing complexity of surgery.1,2,4,6 Studies also revealed that patients over the age of 60 undergoing complex spine surgery are at higher risk for surgical complications.1,2,6 Thoughtful consideration of the complications related to spine surgery is essential. Complications lead to longer hospital stay, higher mortality rate, higher readmission rate, and higher overall cost of treatment,4 all of which lead to diminished efficacy and cost-effectiveness of surgical treatment of degenerative spinal diseases. Although numerous studies have been published on the topic of spine surgery complications in the past, there remains a significant knowledge gap regarding complications related to novel technologies or advanced surgical treatments in the spine that have been developed and gained popularity over the past 2 decades. Critical analysis of past complications can hopefully lead to strategies to avoid future complications and to improve patient outcome. Despite the inherent difficulty involved in getting surgeons to report or discuss the complications encountered, we received an overwhelming response with more than 50 submissions from contributors throughout the world on this topic. A collection of 20 articles that includes reviews of surgical nuances, original articles, and case reports were selected for the current topic. The articles address issues related to diagnostic considerations, complications related to standard surgical techniques such as pedicle screw instrumentation and anterior lumbar interbody fusion, and complications related to more novel treatments such as minimally invasive spine surgery. We hope that you will find the articles from the current issue to be enlightening as you strive to provide the most optimal treatment outcome for all of your patients.

Field of study: Medicine
JCAMP-DX V.6.00 for CHROMATOGRAPHY and MASS SPECTROMETRY HYPHENATED METHODS

The increasing power of modern spectroscopic data systems has led to increasing use of multidimensional analytical techniques. These lead to multidimensional data sets, which need to be stored and exchanged between computer systems. In the definition of a generic structure for multi-dimensional data sets the framework was laid down for NTUPLE IUPAC/JCAMPDX file formats. This technical note builds on the NTUPLE structure with specific recommendations for Chromatography data exchange and hyphenated techniques of chromatography / mass spectrometry. This definition of this format is based on the IUPAC JCAMP-DX protocols, which were developed for the exchange of infrared spectra  and extended to chemical structures , nuclear magnetic resonance data  and mass spectra . This standard of the Joint Committee on Atomic and Molecular Physical Data is of a flexible design. The International Union of Pure and Applied Chemistry (IUPAC) now have responsibility for the support and development of these standards. General developments in the information technology field have constantly to be addressed such as extensions to cover year 2000 compatible date strings and good laboratory practice . The aim of this paper is to use the new Generic IUPAC/JCAMP-DX version 6.00 protocol to define the special requirements for chromatography and extensions for liquid chromatography/mass spectrometry and gas chromatography/mass spectrometry. Optional extensions to the protocol have also been made to allow for lossless data migration to JCAMP-DX from the old ASTM E1947-98 netCDF ANDI standard for chromatography .

Field of study: Chemistry
Single-hoist Operation on Processing Sluice Tilting in Overhauling

The large flat sluice tilted fault occurred in the overhaul,on the condition that hydraulic structure in the field does not permit using motor lifting crane,and the sluice can not be directly lifted,proposed single-hoist operation method of separating left and right hoist and lifting the sluice respectively,then the position of the sluice was adjusted correct and the fault was eliminated,recovered the overhaul operation,no accident happened and ensured the safety of the sluice.

Field of study: Engineering, Physics
A systematic literature review on the industrial use of software process simulation

HighlightsA literature review of software process simulation modelling was performed.None of the claimed benefits could be substantiated with evidence.No evidence exists for the claimed impact and adoption in the industrial practice.Cost of simulation-based studies suggests that it is an expensive undertaking. ContextSoftware process simulation modelling (SPSM) captures the dynamic behaviour and uncertainty in the software process. Existing literature has conflicting claims about its practical usefulness: SPSM is useful and has an industrial impact; SPSM is useful and has no industrial impact yet; SPSM is not useful and has little potential for industry. ObjectiveTo assess the conflicting standpoints on the usefulness of SPSM. MethodA systematic literature review was performed to identify, assess and aggregate empirical evidence on the usefulness of SPSM. ResultsIn the primary studies, to date, the persistent trend is that of proof-of-concept applications of software process simulation for various purposes (e.g. estimation, training, process improvement, etc.). They score poorly on the stated quality criteria. Also only a few studies report some initial evaluation of the simulation models for the intended purposes. ConclusionThere is a lack of conclusive evidence to substantiate the claimed usefulness of SPSM for any of the intended purposes. A few studies that report the cost of applying simulation do not support the claim that it is an inexpensive method. Furthermore, there is a paramount need for improvement in conducting and reporting simulation studies with an emphasis on evaluation against the intended purpose.

Field of study: Computer science, Engineering
Birds nesting survival in disturbed and protected Neotropical savannas

Fragmentation and other habitat disturbances are long known to negatively affect birds, in large part by decreasing nest success due to high nest predation rates. The factors, however, that cause this decrease in nest success are still poorly understood and may vary among regions or species. Here, we show that nest survival is also lower in a disturbed landscape versus a protected cerrado (savanna-like) Neotropical landscape. Also, we tested the importance of garbage in the nest, brood parasitism, microhabitat and bird family in nest survival, controlling for temporal effects. We monitored 144 birds’ nests in a disturbed landscape and 150 nests in a natural reserve of cerrado vegetation in central Brazil, between September and December 2006. We used Program MARK to estimate nest survival probabilities and evaluate the effect of covariates in nest success in the disturbed area. Nest daily survival rate (DSR) was higher in the reserve (survival probability = 29.4%) than in the disturbed landscape (survival probability = 16.6%). Nest daily survival rate (DSR) was smaller in nests with garbage (survival probability = 9.3%) than in nests without garbage (survival probability = 19.5%) in the disturbed landscape. Effects of habitat disturbance on nest survival differed among bird families, with finches and tanagers being more affected mostly due to high nest predation rates. Conservation and management of birds in disturbed landscapes should include actions to decrease nest predation. In poor rural or suburban areas in developing countries, such as Brazil, actions like better garbage treatment may help conserve birds in disturbed landscapes.

Field of study: Environmental science
Thermal and electrical conductivity of Fermi pocket models of underdoped cuprates

Several models of the electronic spectrum in the pseudogap state of underdoped cuprates have been proposed to explain ARPES and STM measurements, which reveal only truncated Fermi pockets instead of a full metallic Fermi surface. We consider the transport properties expected of four physically distinct models, and calculate the thermal and electrical conductivity of the electronic quasiparticles. By proposing transport currents that reflect the close correspondence between quasiparticles on the Fermi pockets in the pseudogap and those near nodes in the superconducting state, we show that measurable transport coefficients provide stringent tests of pseudogap models.

Field of study: Physics