nils-herrmann/clean_scirepeval huggingface dataset:
Generalized recurrence, compactifications, and the Lyapunov topology

We study generalized recurrence for closed relations on locally compact spaces. This includes continuous maps and real flows. The main tools are Lyapunov functions and their compactifications. Under certain conditions it is shown that the Lyapunov functions determine the topology of the space. In  a theory of generalized recurrence in dynamical systems is developed by means of continuous real-valued functions on the phase space. Let {φt} be a real action on the locally compact metric space X. Let L be a real-valued function on X which is non-decreasing on every orbit: L(φt(x)) ≥ L(x) for x ∈ X and t > 0. The generalized recurrent set R is defined to be those x ∈ X for which all such “Lyapunov” functions L are constant on the orbit of x. Clearly R contains the non-wandering points (and therefore the ordinary recurrent points). An intrinsic characterization of R can be obtained by means of prolongational limit sets. An interesting class of flows are those for which the generalized recurrent set is empty. Such flows are characterized by the existence of a Lyapunov function which is strictly increasing on every orbit: L(φt(x)) > L(x) for all x ∈ X and t > 0. It turns out that in this case the Lyapunov functions separate points, and so determine a Hausdorff topology on X. A natural question is whether this “Lyapunov” topology coincides with the original topology of X. Equivalently, if {xn} is a sequence in X, x ∈ X and L(xn)→ L(x) for all Lyapunov functions L, is it the case that xn → x? The purpose of this note is to answer this question in the affirmative (and in fact we will obtain a somewhat more general result). This will require an extensive detour into closed relations on locally compact metric spaces, as well as compactifications of such. In fact, we will obtain the corresponding result for closed relations (and as a consequence for continuous maps).

Field of study: Mathematics
Challenges of Enforcing English as the Medium of Instruction in Upper Primary Classes in Kenya

The purpose of this study was to investigate the challenges of enforcing English as the medium of instruction in upper primary classes based on Vygotsky’s social constructivism and language theory. Mixed methods approach was used in the study. The focus of this study was on public primary schools because they use mother tongue in lower primary school classes. Simple random sampling was used to select 21 out of 70 public primary schools that took part in the study. Purposive sampling was used to select standard seven classes on the premise that they have already had an experience with various languages in school and are also already aware that the official language of communication in school is English. Twenty standard 7 pupils from the selected schools were randomly selected to take part in the pupils’ focus group interviews and one teacher of English language from the selected class in each school was automatically selected to take part in the study. Data was collected using pupils’ focus group interviews and teacher questionnaires. The study found out that teachers face challenges in enforcing English as the medium of instruction in upper primary schools, all the teachers agreed that they make efforts to make their pupils aware of the need to use English for communication both in and outside class and finally most of the pupils reported that they experience difficulties in using English only during English lessons.  Challenges, Enforcing, English, Medium of Instruction, Upper Primary

Field of study: Education
Talking that talk: The language of control, curriculum, and critique

This article analyzes the classroom discourse of an African American female urban community college teacher as she interacts with her class of predominantly African American students. The analysis, informed by perspectives in the ethnography of speaking perspective, focuses on one register variation commonly known as teacher talk . Three categories of teacher talk are presented: (a) the language of control, (b) the language of curriculum, and (c) the language of critique. This study shows that the teacher's talk drew on the rich language and verbal traditions of the African American community. The teacher employs African American English (AAE) language forms and allows them to coexist alongside Standard English (SE). The analysis of teacher talk shows how the language of curriculum, control, and critique served the tripartite function of communicating cognitive information, establishing and maintaining social relationships, and expressing the speaker's attitudes. The analysis also highlights the significance of sociocultural as well as sociopolitical factors that influence learning and the place of AAE in teaching and learning.

Field of study: Education, Linguistics
Trade Contraction and Economic Decline: The Paraguayan Economy under Francia, 1810–1840

I argue here that economic activity fell considerably in the first three decades of Paraguay's early national period, below levels it had attained in the late colonial period and would attain again only after the midnineteenth century. I attribute this economic depression primarily to regional political fragmentation and the institutional regression it triggered. In the i8 ios, the United Provinces of the River Plate sought to keep the former Viceroyalty of the River Plate under a single federal government, but failed to prevent Paraguay's early secession. Their subsequent trade blockades and military threats had profound economic and political effects on Paraguay: revenues from foreign trade taxation fell, scale economies in defence and justice provision vanished, a standing army emerged, government budget deficits worsened, mercantilist regulations heightened, the fiscal burden increased, and transactions costs generally rose. Proponents of federation, more representative governments, and freer trade progressively declined, while supporters of secession, political absolutism, and government regulation became ever more prominent. In the I8zos, blockade relaxations exacerbated economic intervention by the state, which substantially redistributed property rights

Field of study: Political science
Role of an endogenous nitric oxide burst in the resistance of wheat to stripe rust

The stripe rust (or yellow rust) disease caused by Puccinia striiformis Westend is a serious disease of wheat in many areas of the world. The role of NO, which is an important redox-active signalling molecule in plants, was investigated in the wheat-stripe rust system. The phenotypes from interactions of the same wheat variety, Lovrin10, with two different clones of stripe rust strains (P. striiformis Westend), namely China yellow rust (CY)22-2 and CY29-1, which are immune and susceptible reaction types, respectively. The time course of host endogenous NO detected by electron spin resonance indicated that recognition of an avirulent strain was associated with two peaks of NO production. The first peak of NO accumulated in the early infection stage whereas the second peak accumulated in the latent period; however, only a single peak of NO was observed in the latent period for the virulent strain. Furthermore, the activity of pathogen-related protein-phenylalanine ammonia-lyase was higher in the resistant system than in the susceptible system, which suggested that the first NO production was associated with resistance. Exogenous NO improved the activity of phenylalanine ammonia-lyase and induced a resistant response of Lovrin10 to the virulent strain CY29-1, thereby providing further evidence that the first peak of NO production was associated with resistance. These results indicate that the first NO burst in the immune system plays an important role in the resistant reaction of wheat to strip rust.

Field of study: Environmental science
Research on Strategies of ASP Caching

Caching is a classical technology for improving the performance. Using caching correctly can evidently optimize the Web performance, alleviate the server's load and reduce client accessing delays. This article discussed the definition of cache, the importance of using ASP caching on improving Web performance and the sort of ASP caching. And the strategies of using ASP caching to optimize the Web performance were analyzed particularly.

Field of study: Computer science
The Latin American Military Establishment: Some Thoughts on the Origins of its Socio-Political Role and an Illustrative Bibliographical Essay *

Historians from the United States have studied the Latin American military using two principal approaches: in broad, topical studies dealing with the socio-political role of the military, i.e. armies, from colonial times to the present and in monographic works dealing thematically with the political role of the military in a specific country during a specific time. Neither approach boasts a defintive work. Certainly not the former, for the role of the Latin American military is simply too big to be dealt with between the covers of a single volume; nor the latter, because of the necessary exclusivism inherent in dealing with one nation-one period. A third approach, the multinational treatment of the military in Latin America during a fixed period exists, but to date few such works are in print.

Field of study: History
‘Positively Postmodern Stanley’ and Other Law Stories

The legal academy stands on the brink of yet another wave of self-evaluation. While the proliferation of interdisciplinary perspectives on law in the past three decades has resulted in much soul-searching within legal scholarship and legal education, it is arguable that the discipline's quest for self-understanding and change is about to reach new heights (or depths) in the light of some theoretical challenges stemming from recent Continental social and political philosophy. The Fate of Law' provides an engaging contribution to this process. The book consists of five substantial essays which examine, the covernote informs us, the 'problems and prospects of law in the late twentieth century.' The editors of the collection state in the Introduction that their aim in soliciting contributions to the book was to 'invite contemplation about how, if at all, law and legal scholarship have responded, or should respond, to feminist and poststructuralist challenges to claims about law's neutrality, objectivity, and capacity to limit and channel the exercise of power in American life' (p 2). In reply, the contributors, along with the editors jointly, have provided essays dealing in quite distinctive ways with a broad range of issues and movements within contemporary American legal thought. Each essay's treatment of these issues reflects in some way the influence of feminist and post-modernist/structuralist thinking upon the legal academy in recent times. To try and identify a common theme for the collection with greater particularity inevitably invites consideration of the significance and appropriateness of the title, in particular the use of the wordfate. Indeed, this issue seems to give rise to sustained self-consciousness by the two editors towards the end of their Introduction. As one might expect in what undoubtedly is a fin-de-siecle exercise, the editors and contributors confront the issue not just of what has law been like and what position has it brought us to, but also what does it portend. The book thus represents a profound exercise in legal reflexivity, an extended self-conscious intellectual stocktaking by legal theorists. It is not revealing too much to state that each contributor reaches a point of accommodation with the idea of the continued relevance of law. Albeit different narratives are told, no essay suggests a demise for law's story. In view of the title, nevertheless, the question may be asked whether the contributors view law's future from a point of detached, almost tragic hopefulness, or whether greater possibilities exist and something more is required of us both as legal scholars and as subjects of late twentieth-century law. The sense the collection leaves one with, having read each contribution carefully, is the latter rather than the former. Just how far each essay takes this line is question-

Field of study: Law
5-Hydroxy-2-pyrazolines and Some of Their 1-Substituted Analogs

The use of 1,3-dicarbonyl compounds containing strong electron-withdrawing substituents (perfluoroalkyl, 4-nitrophenyl) at one of the carbonyl groups in reaction with hydrazine or its monosubstituted derivatives (4-nitro- and 2,4-dinitrophenylhydrazines) leads to the formation of stable intermediates for the synthesis of pyrazoles (5-hydroxy-2-pyrazolines) or their linear tautomers (hydrazones).

Field of study: Chemistry
Enrichment behavior and transport mechanism of soil-bound PAHs during rainfall-runoff events.

Polycyclic Aromatic Hydrocarbons (PAHs) transported by surface runoff result in  source pollution and jeopardize aquatic ecosystems. The transport mechanism of PAHs during rainfall-runoff events has been rarely studied regarding pervious areas. An experimental system was setup to simulate the runoff pollution process on PAHs-contaminated soil. The enrichment behavior of soil-bound PAHs was investigated. The results show that soil organic matters (SOM), rather than clay particles, seem to be the main carrier of PAHs. The enrichment is highly conditioned on runoff and erosion processes, and its magnitude varies among PAH compounds. It is not feasible to build a simple and universal relationship between enrichment ratio and sediment discharge following the traditional enrichment theory. To estimate the flux of PAHs from pervious areas, soil erosion process has to be clearly understood, and both organic carbon content and composition of SOM should be factored into the calculation.

Field of study: Environmental science
Degradation of Polypropylene and Polyprop/Starch Blends

A high-content starch/polypropylene (IPP) blend with acceptable biodegradation and mechanical properties has been produced. IPP/starch (90/10) blends were tested for photo-degradation under the effects of UV sunlight conditions and an artificial UV lamp for periods of time. The influence of irradiation on the degradability of IPP/starch blends was studied by means of its effects on mechanical properties, thermo-gravimetric analysis (TGA and DSC), x-ray diffraction (XRD), and FTIR spectral analysis. The results indicated that the current of the starch amount into the IPP matrix was responsible for the reduction in mechanical properties of the blends, and decreasing in molecular weight of the IPP/starch blend compared with pure IPP.

Field of study: Materials science
Learning of medical pharmacology via innovation: a personal experience at McMaster and in Asia.

Pharmacology, a discrete preclinical discipline of the traditional medical curriculum, identifies itself distinctly different from the other preclinical or clinical subjects in knowledge base as well as learning/teaching instructions. It exists in series with other pre-clinical courses (e.g., anatomy, biochemistry and physiology), and in parallel with other paraclinical courses such as pathology, microbiology and community medicine. Such arrangement makes learning of pharmacology rather difficult and deficient with regard to its therapeutic relevance and clinical application. In recent years, medical curricula based on clinical cases have emerged as a platform in which pharmacology is one integrated component in a holistic approach to medical education. In this problem-based learning (PBL) model, students learn, with teachers' facilitation, in a student-centered environment, based on self-directed, clinically relevant and case-oriented approach, usually in a small-group tutorial format. In PBL, pharmacology is learned in concert with other subject issues relevant to the case-problem in question, such as anatomy, physiology, pathology, microbiology, population health, behavior science, etc. Students learn via problem-evoked curiosity and motivation, in an environment which encourages free inquiries and intensive discussions in a cooperative rather than competitive atmosphere. Teachers facilitate students' learning objectives rather than deliver pre-packed knowledge and dictate what they think students should learn. A change towards PBL curriculum appears to be beneficial in better preparing the medical students as life-long learners capable of coping with changes in knowledge and skills associated with the progressive and dynamic social/economic transformation in the Asia-Pacific regions. Evidence is presented that this is indeed happening.

Field of study: Biology, Chemistry, Medicine
Design and Operating Experience Problems with Control and Instrumtation Systems Pilgrim Nuclear Power Station - Unit 1

The Pilgrim Nuclear Power Station is a 690 MWe General Electric designed Boiling Water Reactor. Pilgrim is located forty (40) miles south of Boston at Plymouth, Mssachusetts. It is situated on the Atlantic Seaboard (Cape Cod Bay) and uses circulating sea water for condensate cooling in the condenser. Pilgrim was granted a construction permit in August, 1968, achieved initial criticality in June, 1972 and began commercial operation in December, 1972. Bechtel Corporation was the prime contractor. For the first six (6) months of commercial operation, Pilgrim achieved a percent availability of 91.7 percent. I am pleased to report that generally speaking, the instrumentation and control system problems which developed during construction, startup and operation were of a routine nature. No outstanding problems arose requiring indepth re-evaluation and drastic design changes. The instrumentation and control systems have performed as expected. No false scrams have occurred which could be attributed to design deficiencies. Station Technical Specifications require that extensive routine testing on operating equipment be continuously performed to verify operability and locate and eliminate problems that could negate the required operability of said instrumentation when required. This paper discusses some of these Instrumnntation and Control System problems encountered and the solutions to these problems. This paper describes four (4) problems covering design and operating experience with the control and instrumentation systems for Pilgrim Nuclear Power Station Unit 1.

Field of study: Physics
The Community Cloud retrieval for CLimate (CC4CL) – Part 2: The optimal estimation approach

The Community Cloud retrieval for Climate (CC4CL) is a cloud property retrieval system for satellite-based multispectral imagers and is an important component of the Cloud Climate Change Initiative (Cloud_cci) project. In this paper we discuss the optimal estimation retrieval of cloud optical thickness, effective radius and cloud top pressure based on the Optimal Retrieval of Aerosol and Cloud (ORAC) algorithm. Key to this method is the forward model, which includes the clear-sky model, the liquid water and ice cloud models, the surface model including a bidirectional reflectance distribution function (BRDF), and the "fast" radiative transfer solution (which includes a multiple scattering treatment). All of these components and their assumptions and limitations will be discussed in detail. The forward model provides the accuracy appropriate for our retrieval method. The errors are comparable to the instrument noise for cloud optical thicknesses greater than 10. At optical thicknesses less than 10 modeling errors become more significant. The retrieval method is then presented describing optimal estimation in general, the nonlinear inversion method employed, measurement and a priori inputs, the propagation of input uncertainties and the calculation of subsidiary quantities that are derived from the retrieval results. An evaluation of the retrieval was performed using measurements simulated with noise levels appropriate for the MODIS instrument. Results show errors less than 10 % for cloud optical thicknesses greater than 10. Results for clouds of optical thicknesses less than 10 have errors up to 20 %.

Field of study: Environmental science
Enzyme distribution and matrix characteristics in biocatalytic particles.

In a study of Assemblase, an industrial immobilized penicillin-G acylase, various electron microscopic techniques were used to relate intra-particle enzyme heterogeneity with the morphological heterogeneity of the support material at various levels of detail. Transmission electron microscopy was used for the study of intra-particle penicillin-G acylase distribution in Assemblase particles of various sizes; it revealed an abrupt increase in enzyme loading at the particle surface (1.4-fold) and in the areas (designated halo's) surrounding internal macro-voids (7.7-fold). Cryogenic field-emission scanning electron microscopy related these abrupt local enzyme heterogeneities to local heterogeneity of the support material by revealing the presence of dense top layers surrounding both the particle exterior and the internal macro-voids. Furthermore, it showed a very distinct morphological appearance of the halo. Most probably, all these regions contained relatively more chitosan than gelatin (the polymers Assemblase was constructed of), which suggested local polymer demixing during particle production. A basic thermodynamic line of reasoning suggested that a difference in hydrophilicity between the two polymers induced local demixing. In the future, thermodynamic knowledge on such polymer interactions resulting in matrix heterogeneity may be used as a tool for biocatalyst design.

Field of study: Biology, Engineering
Expression of Calcification and Extracellular Matrix Genes in the Cardiovascular System of the Healthy Domestic Sheep (Ovis aries)

The maintenance of a healthy cardiovascular system requires expression of genes that contribute to essential biological activities and repression of those that are associated with functions likely to be detrimental to cardiovascular homeostasis. Vascular calcification is a major disruption to cardiovascular homeostasis, where tissues of the cardiovascular system undergo ectopic calcification and consequent dysfunction, but little is known about the expression of calcification genes in the healthy cardiovascular system. Large animal models are of increasing importance in cardiovascular disease research as they demonstrate more similar cardiovascular features (in terms of anatomy, physiology and size) to humans than do rodent species. We used RNA sequencing results from the sheep, which has been utilized extensively to examine calcification of prosthetic cardiac valves, to explore the transcriptome of the heart and cardiac valves in this large animal, in particular looking at expression of calcification and extracellular matrix genes. We then examined genes implicated in the process of vascular calcification in a wide array of cardiovascular tissues and across multiple developmental stages, using RT-qPCR. Our results demonstrate that there is a balance between genes that promote and those that suppress mineralization during development and across cardiovascular tissues. We show extensive expression of genes encoding proteins involved in formation and maintenance of the extracellular matrix in cardiovascular tissues, and high expression of hematopoietic genes in the cardiac valves. Our analysis will support future research into the functions of implicated genes in the development of valve calcification, and increase the utility of the sheep as a large animal model for understanding ectopic calcification in cardiovascular disease. This study provides a foundation to explore the transcriptome of the developing cardiovascular system and is a valuable resource for the fields of mammalian genomics and cardiovascular research.

Field of study: Biology