nils-herrmann/clean_scirepeval huggingface dataset:
Computerized analysis of mammographic microcalcifications in morphological and texture feature spaces.

We are developing computerized feature extraction and classification methods to analyze malignant and benign microcalcifications on digitized mammograms. Morphological features that described the size, contrast, and shape of microcalcifications and their variations within a cluster were designed to characterize microcalcifications segmented from the mammographic background. Texture features were derived from the spatial gray-level dependence (SGLD) matrices constructed at multiple distances and directions from tissue regions containing microcalcifications. A genetic algorithm (GA) based feature selection technique was used to select the best feature subset from the multi-dimensional feature spaces. The GA-based method was compared to the commonly used feature selection method based on the stepwise linear discriminant analysis (LDA) procedure. Linear discriminant classifiers using the selected features as input predictor variables were formulated for the classification task. The discriminant scores output from the classifiers were analyzed by receiver operating characteristic (ROC) methodology and the classification accuracy was quantified by the area, Az, under the ROC curve. We analyzed a data set of 145 mammographic microcalcification clusters in this study. It was found that the feature subsets selected by the GA-based method are comparable to or slightly better than those selected by the stepwise LDA method. The texture features (Az = 0.84) were more effective than morphological features (Az = 0.79) in distinguishing malignant and benign microcalcifications. The highest classification accuracy (Az = 0.89) was obtained in the combined texture and morphological feature space. The improvement was statistically significant in comparison to classification in either the morphological (p = 0.002) or the texture (p = 0.04) feature space alone. The classifier using the best feature subset from the combined feature space and an appropriate decision threshold could correctly identify 35% of the benign clusters without missing a malignant cluster. When the average discriminant score from all views of the same cluster was used for classification, the Az value increased to 0.93 and the classifier could identify 50% of the benign clusters at 100% sensitivity for malignancy. Alternatively, if the minimum discriminant score from all views of the same cluster was used, the Az value would be 0.90 and a specificity of 32% would be obtained at 100% sensitivity. The results of this study indicate the potential of using combined morphological and texture features for computer-aided classification of microcalcifications.

Field of study: Medicine, Physics
Ultrashort X-ray pulses emitted from laser-field synchrotron radiation

Electron with an appropriate initial velocity injected into an oncoming, ultra-intense circularly polarized laser pulse will execute circular relativistic motion at the peak of laser pulse. The circulating electron then radiates in the same manner as that in the storage ring of a conventional synchrotron source. Owing to the extremely small orbit radius, the laser-field synchrotron radiation thus generated is an attosecond or zeptosecond X-ray pulse. The pulse width of the scattered radiation decreases and the power of the scattered radiation increases with increasing the intensity of the laser pulse and the electron’s initial energy. The unique feature makes the laser-field synchrotron radiation a promising synchrotron radiation source with short wavelength and short duration.

Field of study: Physics
Small vessel vasculitis.

Vasculitis is a primary inflammatory process of large, medium-sized, and small blood vessels. There are multiple entities particularly among small vessel vasculitides. Some are life threatening and require treatment with toxic agents. Diagnostic challenges are posed by low prevalence, controversial classification, inconsistency of clinical and pathological features, and the existence of clinical and pathological "look-alikes". Also, patients may present to a variety of medical specialists, and the diagnosis is often unexpected. The cause often is unknown.



Classification is by vessel size and then on an immunopathologic basis. Generalised and "organ-limited" forms occur. The principal clinical and pathological features are outlined for each of antibasement membrane disease, immune complex disorders including Henoch-Schönlein purpura and cryoglobulinemic vasculitis and the pauci-immune group, which is often associated with antineutrophil cytoplasmic antibody (ANCA), comprising microscopic polyangiitis, Wegener's granulomatosis, and Churg-Strauss syndrome. A brief account is given of "look-alikes" including microthrombotic conditions, which can confound the diagnosis of small vessel vasculitis.



Requirements for diagnosis include full disclosure of the past and present medical history with review of laboratory results, especially diagnostic immunology. Histology should be of targeted biopsies of recent active lesions in preference to blind biopsies. Sampling should be extensive using high-quality thin sections. Systematic microscopic evaluation of architectural features and cellular detail is necessary. Tissue immunofluorescence is a useful adjunct. The final opinion must take all available information into account but may ultimately depend on a critical judgement by the pathologist.

Field of study: Biology, Medicine
"Who Am I to Bring Diversity into the Classroom?" Learning Communities Wrestle with Creating Inclusive College Classrooms.

This study explored the experiences of gateway course instructors during the implementation of pedagogical changes aimed at improving the success of diverse students. A detailed case study was built through analysis of peer observations, focus groups, oral and written reflections, student grades, in-depth interviews, and pre and post student surveys. Results showed that instructors faced three major challenges in implementing pedagogical changes: pragmatic challenges, student-centered challenges, and challenges to instructor self-concept. Embracing a learning paradigm and participating in a learning community helped instructors to manage these challenges and create more inclusive learning environments for students.

Field of study: Education
TOWARD A MESOSCALE OBSERVATION NETWORK IN SOUTHEAST ASIA

The current weather observation network in Southeast Asia is unable to support the accurate monitoring and prediction of the region's predominantly convective weather. Establishing a multisensor mesoscale observation network comprising automated in situ instruments and atmospheric remote sensors (including weather radar) over land and exploiting weather satellite data especially over the sea would significantly improve the quantity and quality of data and benefit numerical weather prediction and tropical atmospheric science research. Several technical and organizational challenges need to be overcome in order to attain this goal. It is hoped that this article would motivate closer regional coordination in plans for developing infrastructure for atmospheric observations for weather research and forecasts in Southeast Asia.

Field of study: Environmental science
Single machine scheduling problems with deteriorating jobs

This paper considers the single machine scheduling problems with deteriorating jobs, i.e. jobs whose processing times are a decreasing linear function of their starting time. It is assumed that jobs have the different basic processing time and same decreasing rate. Based on the analysis of problems, the optimal algorithms are presented for the problems to minimize the sum of earliness penalties subject to no tardy jobs, to minimize the resource consumption with makespan constraints and to minimize the makespan with the total resource consumption constraints.

Field of study: Mathematics
Determination of the moisture content of paprika (Capsicum annuum) powders: a comparative study/ Determinación de la humedad del pimentón (Capsicum annuum): estudio comparativo

The moisture content of 25 different paprika powders was determined by an electronic moisture analyzer at 40, 50, 60, 70, 80, 90, 100 and 105°C by near infrared spectroscopy, using both peak area and peak height for the water; and by the traditional drying method, using an electric oven at 100°C for 1, 2 and 3 h. The data matrix was evaluated by principal component analysis. It was established that the moisture content of paprika powders can be equally determined by each method. The use of the NIR method has been proposed because it is both rapid and accurate, and the presence of other volatile compounds does not influence the reliability of the determination of the moisture content.

Field of study: Agricultural and Food sciences
Design of Radiation-Hardened RF Low-Noise Amplifiers Using Inverse-Mode SiGe HBTs

A SiGe RF low-noise amplifier (LNA) with built-in tolerance to single-event transients is proposed. The LNA utilizes an inverse-mode SiGe HBT for the common-base transistor in a cascode core. This new cascode configuration exhibits reduced transient peaks and shorter transient durations compared to the conventional cascode one. The improved SET response was verified with through-wafer two-photon absorption pulsed-laser experiments and supported via mixed-mode TCAD simulations. In addition, analysis of the RF performance and the reliability issues associated with the inverse-mode operation further suggests this new cascode structure can be a strong contender for space-based applications. The LNA with the inverse-mode-based cascode core was fabricated in a 130 nm SiGe BiCMOS platform and has similar RF performance to the conventional schematic-based LNA, further validating the proposed approach.

Field of study: Physics
Diatoms as indicators of hydrological and climatic changes in Laguna Potrok Aike (Patagonia) since the Late Pleistocene

Recently, several investigations using lacustrine sediments have provided an enormous amount of information to reconstruct past environmental changes. In the framework of the Potrok Aike Maar Lake Sediment Archive Drilling Project (PASADO) more than 500 m of sediment cores were retrieved from the center of this lake. This contribution is centered in the diatom record of a core covering over the last 50 cal. ka BP. Nine statistically significant zones were determined based on changes in the assemblages of more than 200 species of diatoms, showing changes in productivity throughout time. Although it appears that the presence of mass waste events may have triggered some peaks in productivity, large fluctuations in diatom abundance and changes in species assemblages coincide with distinctive Antarctic warm events, A2 and A1, described for Antarctic ice cores at around 44.5 and 38.5 kyr BP respectively ( Blunier and Brook, 2001 ). Furthermore, a smaller diatom peak may account for the A3 event compatible with a new OSL-based chronological model. Up to now they have only been described for Antarctica, but the fact that these events are recorded in southern Patagonia indicates their magnitude and importance for climate in the Southern Hemisphere.

Field of study: Environmental science, Geography
Modelling parallel access to shared resources in a distributed file system using queueing networks

This paper presents a practical and noniterative method for evaluating queueing networks in which delays due to locking of files are represented using measurable parameters. A queueing network model of a distributed file system is introduced. The model allows read and write locks and allows multiple classes of users to be represented. The model parameters are estimated from the values of measurable quantities. An approximation of branching probabilities is used to direct transactions to their original sites when they leave a remote host. The service times of lock servers are calculated as functions of the loads on all service centers. The various lock granularities may be represented by this model. Performance measures applicable to the evaluation of computer systems are introduced and evaluated. An example involving a distributed file system and measurement data collected in a small business installation is given to compare performance measures and locking delays provided by the simulation and analytic models for various lock granularities.

Field of study: Computer science, Engineering
SIMPLIFIED CALCULATION OF AXIAL DEFORMATION OF CONCRETE MEMBERS EXPOSED TO HIGH TEMPERATURE

Concrete thermal inertia will result in a nonuniform temperature distribution in the cross section of concrete members exposed to fire and soon afterwards the corresponding strain will be induced. This strain is called the nonuniform temperature distribution strain (NTDS). By finite element method and based on known test results, the thermal-stress coupled properties of the NTDS are analyzed; the influencing extent of these factors, such as the size of cross section, velocity of heating, etc., are determined, and the corresponding simplified calculation formulae for the NTDS and the equivalent temperature are developed. The simplified analysis can transform the problem of the axial deformation induced by the NTDS to that of a uniform temperature distribution in the cross section of concrete members, and the equivalent temperature can be used to analyze mechanical problems of concrete under elevated temperature.

Field of study: Engineering
The mass of a static charged sphere

The field of a static, charged sphere is investigated using general relativity. InNordström's exterior solution the parametersm ande, referring to mass and charge, are unrelated, and indeedm can be put equal to zero. It is shown that, if the interior solution is considered,m cannot be put zero unless the matter density is negative. The contribution of the electric field energy to the gravitational mass is estimated using certain special models.A model is given in which the gravitational attraction of the charged matter balances its electrical repulsion. If the radius is allowed to tend to zero, this gives a model of a point charge with finite and non-zero mass and charge.

Field of study: Physics
Dominant Narratives and Historical Perspective in Time Travel Stories: A Case Study of Doctor Who

Historical novels, films, and other media can disrupt or reinforce dominant narratives about the past. Educators must be careful that when they attempt to select material from a range of seemingly diverse perspectives, they do not choose content that nevertheless maintains problematic depictions of people, places, and events. Time travel stories offer a unique opportunity for students to consider, discuss, and research both “the past” and popular media’s construction of the past, as well as confront their assumptions about what they believe is “true to history” and why. This article presents a case study and content analysis of the time travel TV show Doctor Who, and its narrative construction of the past around race and gender in particular. Implications are discussed for how the show might teach students about historical perspective and popular media’s influence on perceptions of history in subtle and overt ways.

Field of study: Sociology
Cyanobacterial diversity of western European biological soil crusts along a latitudinal gradient

Cyanobacteria associated with biological soil crusts (BSCs) have important attributes, such as nitrogen fixation and soil stabilisation. However, research on these organisms has been minimal, and their diversity and distribution throughout temperate Europe is currently unknown. The SCIN (Soil Crust International) project is a multidisciplinary research initiative that aims to achieve improved understanding of the BSCs of Europe, one facet being an investigation into the cyanobacterial communities of BSCs across a latitudinal gradient. Cyanobacteria assemblages were analysed by both morphological and molecular analysis. Two treatments were applied prior to DNA extraction, continued sample wetting and a dry sample process, and 16S ribosomal RNA (rRNA) amplicons were processed by Illumina MiSeq sequencing. The results reveal high and variable cyanobacterial diversity with each site showing a unique assemblage. Many common cyanobacterial genera, for example Nostoc and Microcoleus, were found in all sites but the abundances of different genera varied considerably. The polyphasic approach was found to be essential in recording the presence of important cyanobacteria that a single method itself did not highlight. The wet and dry treatments showed some differences in diversity, but mainly in abundance, this may suggest how cyanobacterial composition of BSCs changes with seasonal variability.

Field of study: Biology, Environmental science
Management and business in Britain and France : the age of the corporate economy

For generations, the uneasy relationship between Britain and France has captured the popular and scholarly imagination. Comparative studies between the two countries abound, from political systems to eating habits: hitherto they have not extended to business history. There is now growing interest in comparative business systems, practices, and performance. In these areas comparison with America, Germany, or Japan have taken precedence. This volume, with contributions from leading British and French experts, explores comparative developments and trends in the two countries which for so long were the guiding lights of Europe and the world. In particular it looks at three main dimensions - the family firm; education and training; and mergers and company structure. With a mixture of case-studies, sectoral analysis, and wider-ranging comparison, the book will be a useful addition to an understanding of the evolution of business organization, competitivness, and performance.

Field of study: Economics, History
Paradoxical effect of a GnRH agonist on steroidogenesis in cultured monkey granulosa cells.

In this study we demonstrate: (i) The GnRH agonist exerts a direct dose-dependent stimulative effect on the aromatase activity and progesterone production in cultured monkey granulosa cells; (ii) the stimulative effect on steroidogenesis can be completely blocked by concomitant treatment with a GnRH antagonist, suggesting that the actions of GnRH are mediated through stringent stereospecific recognition sites; (iii) in addition to the stimulative effect, the GnRH agonist in the presence of gonadotropins also exerts an inhibitory effect, even though the peptide by itself is more effective in the stimulation of steroidogenesis, and the stimulation of gonadotropin on steroidogenesis could be gradually restored by decreasing the concentration of the GnRH agonist in the culture; and (iv) paradoxical effect can also be observed in the presence of cAMP-inducing agents, suggesting that the inhibitory action of the peptide on gonadotropin-induced steroidogenesis is localized at a step distal to the stringent recognition sites.

Field of study: Chemistry
Institutional Policy and Its Abuses.

Observers of organizational life have treated policy-makers and policy manuals to caustic verbal blows for years. For example, it has been said that the last act of a dying organization is to issue a greatly enlarged policy manual. But policy itself is like any other management tool: it can be used or abused. Thus, the question for college administrators is not whether one should have formal policy, but rather what policies are needed and how they can be put to work for more effective organizational functioning. The purposes of this article are to review the role of institutional policy, to cite frequent abuses of policy, and finally to delineate the several principles of policy management. It is hoped that a review of the pitfalls and standards of policy application will provide a set of criteria against which a university administration may gauge the effectiveness of its existing policy management.

Field of study: Education
High-Temperature High-Efficiency Solar Thermoelectric Generators

Inspired by recent high-efficiency thermoelectric modules, we consider thermoelectrics for terrestrial applications in concentrated solar thermoelectric generators (STEGs). The STEG is modeled as two subsystems: a TEG, and a solar absorber that efficiently captures the concentrated sunlight and limits radiative losses from the system. The TEG subsystem is modeled using thermoelectric compatibility theory; this model does not constrain the material properties to be constant with temperature. Considering a three-stage TEG based on current record modules, this model suggests that 18% efficiency could be experimentally expected with a temperature gradient of 1000°C to 100°C. Achieving 15% overall STEG efficiency thus requires an absorber efficiency above 85%, and we consider two methods to achieve this: solar-selective absorbers and thermally insulating cavities. When the TEG and absorber subsystem models are combined, we expect that the STEG modeled here could achieve 15% efficiency with optical concentration between 250 and 300 suns.

Field of study: Materials science
Alternative Method of Mitigating Risk on Medium and Large Corporations

High operating costs and complexity of risks are impacting negatively on corporations’ profitability despite practicing corporate governance. Corporate governance requires that the management develops frameworks, structures and guidance to manage enterprise risk. The traditional methods of mitigating risk has relied heavily on insurance as the only mean of protecting enterprise against risks. This is now becoming too expensive for corporations, and, is not able to cover all risk exposures. This forms the basis of the research problem in this study. The purpose and objective of this study is to establish alternative methods of mitigating risks in corporations and, develop models for computing benefits accruing to the corporations as a result of using the new alternative method. As such, this study identifies financial assets, sinking fund, ploughing back of premiums as possible investments where foregone insurance premiums can be invested and, develop a model for computing earnings resulting from such investments. This study applies Actuarial Theory, Financial Theory of Risk Transfer, Modigliani and Miller Theory and Agency Theory, and use both primary and secondary data collected from National Transport and Safety Authority, Kenya and Registrar of Motor vehicles, Kenya target populations, namely number of countries in Europe and North America and the number of insurance companies in Kenya. This study is of significance to the business communities, scholars and researchers, the government and the general public by: (1), providing a better understanding for designing and formulating risk management policy in their organizations, (2), providing mechanism for investing the foregone insurance premium and (3), strengthening knowledge and further research in this area. In summary this study is tenable and a better alternative to ever increasing insurance premiums.

Field of study: Business