nils-herrmann/clean_scirepeval huggingface dataset:
Head-end secondary flows in solid-propellant rockets due to transverse acoustic waves

The secondary flowfield in the head-end region of solid-propellant rocket motor combustion chamber is derived based on a simplified model. Employing a small perturbation technique, a secondary nonoscillatory perturbation mean flow is generated in a quiescent fluid on an infinite flat plate by the presence of a small amplitude transverse traveling wave motion. Effects of compressibility, variable viscosity, and heat transfer are considered in the study. The firstorder oscillatory flow results in a steady mass transport outside of the viscous boundary layer. The secondary perturbation mean flow is found to be a complex three-dimensional spiral motion. The predicted flowfield in this region gives a qualitative explanation of the mechanism of formation of strong axial vortex filament that has been observed in cylindrical combustion chambers during unstable burning.

Field of study: Physics
Rapid and label-free detection of protein a by aptamer-tethered porous silicon nanostructures.

Protein A, which is secreted by and displayed on the cell membrane of Staphylococcus aureus is an important biomarker for S. aureus. Thus, its rapid and specific detection may facilitate the pathogen identification and initiation of proper treatment. Herein, we present a simple, label-free and rapid optical biosensor enabling specific detection of protein A. Protein A-binding aptamer serves as the capture probe and is immobilized onto a nanostructured porous silicon thin film, which serves as the optical transducer element. We demonstrate high sensitivity of the biosensor with a linear detection range between 8 and 23μM. The apparent dissociation constant was determined as 13.98μM and the LoD is 3.17μM. Harnessing the affinity between protein A and antibodies, a sandwich assay format was developed to amplify the optical signal associated with protein A capture by the aptamer. Using this approach, we increase the sensitivity of the biosensor, resulting in a three times lower LoD.

Field of study: Biology, Engineering
Middle–Upper Ordovician (Darriwilian–Sandbian) paired carbon and sulfur isotope stratigraphy from the Appalachian Basin, USA: Implications for dynamic redox conditions spanning the peak of the Great Ordovician Biodiversification Event

The Evans Ferry section from the Appalachian Basin of eastern North America has been analyzed for chemostratigraphic trends to elucidate possible causal mechanisms facilitating the Great Ordovician Biodiversification Event (GOBE). Paired stable isotope (δ13C and δ34S) analyses were used in this carbonate-dominated locality from the Appalachian Basin to reconstruct the marine redox states during this key period of rapid biodiversification. This succession is one of the most expanded Sandbian Stage (Upper Ordovician) deposits known from North America, and it allows new high-resolution reconstructions of long-term, global carbon and sulfur cycle fluctuations. The integrated geochemical and sequence-stratigraphic investigation presented here from the Laurentian epeiric seaway allows for possible identification of the contraction and expansion of reducing water masses during the Middle–Late Ordovician that may have been linked to global-marine paleoredox dynamics. Utilizing new conodont-based 87Sr/86Sr isotope stratigraphy along with previous conodont biostratigraphy, we can confidently correlate our stable isotope profiles to other carbonate successions globally. Carbonate facies indicate that this area experienced partial restriction from open-marine conditions during certain intervals in the Sandbian. These semi-restricted environments record carbon (δ13Ccarb) isotope trends that are secular in nature, as they can be correlated to other successions across Laurentia and Baltica. We identify several intervals when δ13Ccarb and δ34SCAS (carbonate-associated sulfate) trends are decoupled. These inverse stratigraphic trends are, at times, followed by parallel positive shifts in δ13Ccarb and δ34SCAS. Causal mechanisms for the observed decoupled δ13C and δ34S trends may include a wide variety of factors such as more closed-system, local biogeochemical processes associated in part with diagenesis, or they could instead reflect variations in the global fluxes of organic matter and pyrite burial linked to changing marine paleoredox conditions. The positive covariation in trends presented here likely represents transient increases in organic carbon and pyrite burial in response to expansion of reducing marine environments.

Field of study: Environmental science, Geography
Designing Solutions for Clean Water on Cape Cod: Engaging Communities to Improve Decision Making.

Many of the remaining mechanisms for reducing land-based nitrogen release in coastal communities depend on behavior change, social acceptance, and public support of localized mitigation programs. These needs necessitate appropriate and effective stakeholder engagement. Cape Cod, Massachusetts, USA, is one example of an area undergoing significant local, regional, state and federal decision-making processes to address nitrogen impacts on coastal waterbodies through an update to its Area Wide Water Quality Management Plan (208 Plan). The 208 Plan Update seeks to support mitigation of nitrogen pollution and restore estuarine health through active community engagement with elected officials, town staff, citizens, and other stakeholders across its 53 embayment watersheds, 35 of which are deemed impaired. With an economy deeply tied to the environment, the region is in the difficult position of needing to make significant infrastructure investments to maintain its reputation for high quality coastal waters. It is the first region in the United States to undergo an extensive revisit of its Area Wide Water Quality Management Plan developed pursuant to Section 208of the federal Clean Water Act for the purpose of addressing nitrogen. The community engagement process for the 208 Plan Update set forth to 1) understand the range of perspectives regarding the extent of the nitrogen impacts as well as the possible solutions, 2) ensure two-way communication of available information, and 3) build trust through a transparent process. The process specifically applied a number of different mechanisms for community engagement which enabled progress in addressing nitrogen management needs. The process helped to determine and address barriers to successful implementation of nitrogen mitigation plans and resulted in a framework for watershed-based planning that relies on regional coordination and supports local selection of mitigation strategies. As a result, communities in the region are developing innovative cross-municipal partnerships and committing to fund infrastructure necessary to decrease nitrogen loading to coastal embayments.

Field of study: Environmental science
Second universal limit of wave segment propagation in excitable media.

A free-boundary approach is applied to derive universal relationships between the excitability and the velocity and the shape of stabilized wave segments in a broad class of excitable media. In the earlier discovered low excitability limit wave segments approach critical fingers. We demonstrate the existence of a second universal limit (a motionless circular shaped spot) in highly excitable media. Analytically obtained asymptotic relationships and interpolation formula connecting both excitability limits are in good quantitative agreement with results from numerical simulations.

Field of study: Physics
Determinants of School Enrolment in Pakistan

Education is always considered as the significant determinants for the development of any economy. School Enrolment shows that how much education is common within the children of the country. Taking the importance of enrolment, the current study examines the influence of variables like government spending and numbers of schools on the student school enrolment in Pakistan. Time series data has been collected on student enrolment, government spending and numbers of schools for the period from 2001 to 2010. Model is estimated through regression. The results of study show positive association of numbers of schools and government spending with student enrolment in Pakistan. At the end of study give some policy implications that government should increase expenditure in term of education for higher school enrolment rates in Pakistan and re-opening of ghost schools all around the country so more and more children in urban and rural areas children access school education.  Government expenditure, Enrolment, Pakistan, Numbers of School,

Field of study: Education
A double-blind, placebo-controlled trial to assess the efficacy of quetiapine fumarate XR in very heavy-drinking alcohol-dependent patients.

Despite advances in developing medications to treat alcohol dependence, few such medications have been approved by the Food and Drug Administration. Identified molecular targets are encouraging and can lead to the development and testing of new compounds. Atypical antipsychotic medications have been explored with varying results. Prior research suggests that the antipsychotic quetiapine may be beneficial in an alcohol-dependent population of very heavy drinkers.



In this double-blind, placebo-controlled trial, 224 alcohol-dependent patients who reported very heavy drinking were recruited across 5 clinical sites. Patients received either quetiapine or placebo and Medical Management behavioral intervention. Patients were stratified on gender, clinical site, and reduction in drinking prior to randomization.



No differences between the quetiapine and placebo groups were detected in the primary outcome, percentage heavy-drinking days, or other drinking outcomes. Quetiapine significantly reduced depressive symptoms and improved sleep but had no effect on other nondrinking outcomes. Results from a subgroup analysis suggest that patients who reduced their drinking prior to randomization had significantly better drinking outcomes during the maintenance phase (p < 0.0001). No significant interactions, however, were observed between reducer status and treatment group. Finally, quetiapine was generally well tolerated. Statistically significant adverse events that were more common with quetiapine versus placebo include dizziness (14 vs. 4%), dry mouth (32 vs. 9%), dyspepsia (13 vs. 2%), increased appetite (11 vs. 1%), sedation (15 vs. 3%), and somnolence (34 vs. 9%).



This multisite clinical trial showed no efficacy for quetiapine compared with placebo at reducing alcohol consumption in heavy-drinking alcohol-dependent patients.

Field of study: Medicine
Current concepts in pharmacotherapy of substance abuse

The cost to society of alcohol, tobacco, and illicit drug dependence is enormous. Although the importance of treatment for substance abuse to public health is increasingly acknowledged, pharmacotherapy is generally underutilized. However, the selection of medications for clinical testing is increasingly guided by the rapidly evolving science of addictive drugs and behavior. The benefit of medication for smoking cessation is firmly established, particularly for nicotine replacement and antidepressant therapy. Naltrexone is an important addition to the pharmacopoeia, and acamprosate may soon be approved as well. Although no new medications are approved for cocaine and amphetamine abuse, a variety of candidate treatments have shown promise in ongoing studies. Opiate substitution therapy is highly effective for rehabilitation of heroin addiction, and several alternative forms will soon be available; alternative forms of opiate detoxification have also received attention. Overall, there is increasing recognition that physicians have an obligation to identify and treat all forms of substance dependence, although knowledge of the efficacy of the available treatments is steadily increasing.

Field of study: Medicine, Psychology
Prominence of ichnologically influenced macroporosity in the karst Biscayne aquifer: Stratiform "super-K" zones

A combination of cyclostratigraphic, ichnologic, and borehole geophysical analyses of continuous core holes; tracer-test analyses; and lattice Boltzmann fl ow simulations was used to quantify biogenic macroporosity and permeability of the Biscayne aquifer, southeastern Florida. Biogenic macroporosity largely manifests as: (1) ichnogenic macroporosity primarily related to postdepositional burrowing activity by callianassid shrimp and fossilization of components of their complex burrow systems (Ophiomorpha); and (2) biomoldic macroporosity originating from dissolution of fossil hard parts, principally mollusk shells. Ophiomorpha-dominated ichnofabric provides the greatest contribution to hydrologic characteristics in the Biscayne aquifer in a 345 km 2 study area. Stratiform tabular-shaped units of thalassinidean-associated macroporosity are commonly confi ned to the lower part of upward-shallowing highfrequency cycles, throughout aggradational cycles, and, in one case, they stack vertically within the lower part of a high-frequency cycle set. Broad continuity of many of the macroporous units concentrates groundwater fl ow in extremely permeable passageways, thus making the aquifer vulnerable to long-distance transport of contaminants. Ichnogenic macroporosity represents an alternative pathway for concentrated groundwater fl ow that differs considerably from standard karst fl ow-system paradigms, which describe groundwater movement through fractures and cavernous dissolution features. Permeabilities were calculated using lattice Boltzmann methods (LBMs) applied to computer renderings assembled from X-ray computed tomography scans of various biogenic macroporous limestone samples. The highest simulated LBM permeabilities were about fi ve orders of magnitude greater than standard laboratory measurements using air-permeability methods, which are limited in their application to extremely permeable macroporous rock samples. Based on their close conformance to analytical solutions for pipe fl ow, LBMs offer a new means of obtaining accurate permeability values for such materials. We suggest that the stratiform ichnogenic groundwater fl ow zones have permeabilities even more extreme (~2‐5 orders of magnitude higher) than the Jurassic “super-K” zones of the giant Ghawar oil fi eld. The fl ow zones of the Pleistocene Biscayne aquifer provide examples of ichnogenic macroporosity for comparative analysis of origin and evolution in other carbonate aquifers, as well as petroleum reservoirs.

Field of study: Geology
Resonanzerscheinungen in der Ausgangsleistung eines He-Ne-Lasers im axialen Magnetfeld

The output power of a He-Ne-laser (λ=633 nm) has been measured as a function of the strength of an axial magnetic field. This function has intensity dips in the regions where the Zeeman splitting is equal to combination frequencies of different modes. These dips have practically the shape of the natural line. The effect enables to measureg-factors, because the Zeeman splitting can be recorded with a resolution, limited only by the natural line width without Doppler broadening.

Field of study: Physics
The relationship between the film properties and the preparation conditions for a-Si:H grown by homogeneous chemical vapour deposition

A study is presented of a-Si:H films prepared by homogeneous chemical vapour deposition (HOMOCVD). a-Si:H is known as a material which is rather stable against degradation by light. The effect of deposition conditions on the parameters characterizing the structural and electronic properties of the films is studied, and two general cases of constant and variable gas-phase conditions were considered. The obtained data suggest that the optoelectronic properties of HOMOCVD a-Si:H are not strongly related to the structural parameters characterizing the film structure on a large scale and a certain decrease in the density and homogeneity of the a-Si:H films does not lead to their deterioration.

Field of study: Materials science
Influence of forest stand factors on the amount of Monochamus alternatus Hope

The traps were placed in the Ma′anshan forest farm according to different forest types,and in the same forest type according to different landforms,shade densities,slope directions and the locations of the forest.The results showed that the influence of ground coverage rate(F=16.02,P=0.0003),aspects(P=2.32,F=0.0378) and location of the forest(F=4.29,P=0.0447) on the amount of Monochamus alternatus Hope were significant(P0.05),but the influence of forest types(F=1.67,P=0.1660) and shade densities(F=0.09,P=0.7666) on the amount of M.alternatus were not significant.

Field of study: Agricultural and Food sciences
Using the Storypath Approach to Make Local Government Understandable

Learning about local government seems boring and irrelevant to most young people, particularly to students from high-poverty backgrounds. The authors explore a promising approach for solving this problem, Storypath, which engages students in authentic learning and active citizenship. The Storypath approach is based on a narrative in which students create the setting, become the characters, and then solve the problems presented through the story's plot. The authors describe how a group of students created a small town faced with a proposed shopping mall. Students, in their roles as townspeople—business owners, employees, and elected and appointed officials (mayor, city council members, and planning commission members)—participated in determining what was best for their town.

Field of study: Sociology
An Analysis of the New York City Police Department's “Stop-and-Frisk” Policy in the Context of Claims of Racial Bias

Recent studies by police departments and researchers confirm that police stop persons of racial and ethnic minority groups more often than whites relative to their proportions in the population. However, it has been argued that stop rates more accurately reflect rates of crimes committed by each ethnic group, or that stop rates reflect elevated rates in specific social areas, such as neighborhoods or precincts. Most of the research on stop rates and police–citizen interactions has focused on traffic stops, and analyses of pedestrian stops are rare. In this article we analyze data from 125,000 pedestrian stops by the New York Police Department over a 15-month period. We disaggregate stops by police precinct and compare stop rates by racial and ethnic group, controlling for previous race-specific arrest rates. We use hierarchical multilevel models to adjust for precinct-level variability, thus directly addressing the question of geographic heterogeneity that arises in the analysis of pedestrian stops. We find that persons of African and Hispanic descent were stopped more frequently than whites, even after controlling for precinct variability and race-specific estimates of crime participation.

Field of study: Mathematics
Klaar met skool - wat nou?

The Dairy Mail het van Maart 2007 af by 'n paar landbouskole regoor die land gaan inloer om te sien waarmee die jong boere van ons land hulle besig hou. Maar wat doen 'n mens nou as jy in matriek is en so baie van jou landbouvakke gehou het, dat jy dit oorweeg om verder daarin te studeer?

Field of study: Agricultural and Food sciences
Solving Generalized Small Inverse Problems

We introduce a "generalized small inverse problem (GSIP)" and present an algorithm for solving this problem. GSIP is formulated as finding small solutions of f(x0, x1, . . . , xn) = x0h(x1, . . . , xn) + C = 0(mod M) for an n-variate polynomial h, non-zero integers C and M. Our algorithm is based on lattice-based Coppersmith technique. We provide a strategy for construction of a lattice basis for solving f = 0, which are systematically transformed from a lattice basis for solving h = 0. Then, we derive an upper bound such that the target problem can be solved in polynomial time in log M in an explicit form. Since GSIPs include some RSA-related problems, our algorithm is applicable to them. For example, the small key attacks by Boneh and Durfee are refound automatically.

Field of study: Computer science, Mathematics
Tame cuspidal representations in non-defining characteristics

Let k be a non-archimedean local field of odd residual characteristic p. Let G be a (connected) reductive group that splits over a tamely ramified field extension of k. We revisit Yu's construction of smooth complex representations of G(k) from a slightly different perspective and provide a proof that the resulting representations are supercuspidal. 
Moreover, we show that an analogous construction yields smooth, irreducible, cuspidal representations over an arbitrary algebraically closed field R of characteristic different from p and that this construction provides all smooth, irreducible, cuspidal R-representations if p does not divide the order of the Weyl group of G.

Field of study: Mathematics
Fisheries and trade of seahorses in Brazil: historical perspective, current trends, and future directions

Seahorses (Hippocampus spp.) are globally threatened by overexploitation and habitat destruction; they are also regarded as susceptible to heavy exploitation due to some of their life-history traits. From an economic perspective, they are fishes with high monetary value and marketability. Seahorses are now listed in Appendix II of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora), to ensure that the international trade is not detrimental to the survival of wild populations; the effectiveness evaluation of these international controls needs comparable monitoring data, including evaluation of spatial and temporal trends. This study assesses the seahorse trade in Brazil, aiming to detect trends in catch levels, volumes and prices. Our main findings were: the dried trade was unregulated, without formal records, and primarily domestic, although records of unreported exports existed; it was primarily sustained by incidental captures in trawl nets. The live seahorse trade was mainly destined for exports, and regulated through national quotas. Between 2002 and 2009, mean prices for dried seahorses ranged from US$1.06 ± 0.46 (level 1 traders) to US$2.78 ± 0.68 (end-sellers) each, while mean prices for each live seahorse traded on the domestic market (1997–2009) ranged from US$1.13 ± 0.02 (level 1 traders) to US$10.08 ± 1.71 (retailers). Mean declared export price (2006–2008) was 15.57 ± 10.87. Enhanced implementation of the CITES listing in Brazil will require further research, and additional measures to address both direct and indirect fishing pressure on seahorse populations.

Field of study: Environmental science