cssi/SciSciGPT-SciSciNet huggingface dataset:
Scale Aircraft Fabrication Laboratory to Increase Undergraduate Student Interest in Aerospace Engineering

According to the U.S. Bureau of Labor Statistics the job outlook for aerospace engineers is expected to be strong in the near term. Additionally, the employment forecast is likely to increase significantly in the future to cover the large retirement expected from a generation of Cold War aerospace scientist and engineers. While much of aerospace engineering requires graduate level study, it is important to excite engineering students, especially in the early part of their education, in the principles of aerospace engineering in a fun, creative, and engaging way. An elective course developed at RIT targets this early engineering demographic by seeking to give the students a hands-on laboratory in the fundamentals of scale-sized aircraft fabrication and test. The goal is to inspire students who either have not decided upon an engineering concentration or are looking to increase their awareness and understanding in a much needed field as they plan their future careers.
Future Research Directions for Multimorbidity Involving Cardiovascular Diseases

Multimorbidity, defined as the co-occurrence of two or more chronic conditions, increases with age and may be found in approximately two-thirds of older adults in population studies, commonly including a variety of cardiovascular risk factors and chronic diseases. This article offers a research agenda for cardiovascular disease from a patient-centered multimorbidity perspective. Definitional issues remain for multimorbidity, along with high interest in understanding the inter-relationships between aging, diseases, treatments, and organ dysfunction in the development and progression of multimorbidity. Clinical trials, practice-based and population-based observational studies, and linkages of big data can play a role in improving health outcomes among persons with multimorbidity.
Extreme Oxatriquinanes: Structural Characterization of α-Oxyoxonium Species with Extraordinarily Long Carbon–Oxygen Bonds

The first stable α-oxyoxonium species have been synthesized and characterized. Strong donation of nonbonding electrons on oxygen into the adjacent σ*(C–O+) orbital was predicted by modeling to result in unheard of carbon–oxygen bond lengths. The kinetic stability of the triquinane ring system provides a platform upon which to study these otherwise elusive species, which are evocative of intermediates on the acetalization reaction pathway. Crystallographic analysis of the α-hydroxy and α-methoxy oxatriquinane triflates reveals 1.658 and 1.619 A C–O+ bond lengths, respectively, the former of which is a new record for the C–O bond.
Trusted materials using orthogonal testing. 2015 Annual report

The purpose of this project is to prove (or disprove) that a reasonable number of simple tests can be used to provide a unique data signature for materials, changes in which could serve as a harbinger of material deviation, prompting further evaluations. The routine tests are mutually orthogonal to any currently required materials specification tests.
Rhabdomyolysis Associated with Urethral Stricture Repair: Report of a Case

A case is reported of rhabdomyolysis and acute tubular necrosis following an exaggerated knee-chest position to repair a urethral stricture. To our knowledge this is the first case reported of this syndrome occurring after a urologic procedure.
Inaccessibility of online PDR to pharmacists.

I recently learned that pharmacists no longer have online access to the Physicians’ Desk Reference ( PDR ) ([www.PDR.net][1]). Access is now restricted to physicians, physician assistants, nurse practitioners, and medical students. After several telephone calls, I was able to communicate with a
Prokaryotic Virus Orthologous Groups (pVOGs): a resource for comparative genomics and protein family annotation

Viruses are the most abundant and diverse biological entities on earth, and while most of this diversity remains completely unexplored, advances in genome sequencing have provided unprecedented glimpses into the virosphere. The Prokaryotic Virus Orthologous Groups (pVOGs, formerly called Phage Orthologous Groups, POGs) resource has aided in this task over the past decade by using automated methods to keep pace with the rapid increase in genomic data. The uses of pVOGs include functional annotation of viral proteins, identification of genes and viruses in uncharacterized DNA samples, phylogenetic analysis, large-scale comparative genomics projects, and more. The pVOGs database represents a comprehensive set of orthologous gene families shared across multiple complete genomes of viruses that infect bacterial or archaeal hosts (viruses of eukaryotes will be added at a future date). The pVOGs are constructed within the Clusters of Orthologous Groups (COGs) framework that is widely used for orthology identification in prokaryotes. Since the previous release of the POGs, the size has tripled to nearly 3000 genomes and 300 000 proteins, and the number of conserved orthologous groups doubled to 9518. User-friendly webpages are available, including multiple sequence alignments and HMM profiles for each VOG. These changes provide major improvements to the pVOGs database, at a time of rapid advances in virus genomics. The pVOGs database is hosted jointly at the University of Iowa at http://dmk-brain.ecn.uiowa.edu/pVOGs and the NCBI at ftp://ftp.ncbi.nlm.nih.gov/pub/kristensen/pVOGs/home.html.
Technetium-99m-Teboroxime: A New Agent for Myocardial Perfusion Imaging

This is the first article in a four-part series on new radiopharmaceuticals. Upon completion of this article, the nuclear medicine technologist will be able to: (1) understand the important aspects of this technetium-99m-labeled myocardial perfusion agent, and (2) identify important imaging parameters.
Theory and optical design of x-ray echo spectrometers

X-ray echo spectroscopy, a space-domain counterpart of neutron spin echo, is a recently proposed inelastic x-ray scattering (IXS) technique. X-ray echo spectroscopy relies on imaging IXS spectra and does not require x-ray monochromatization. Due to this, the echo-type IXS spectrometers are broadband, and thus have a potential to simultaneously provide dramatically increased signal strength, reduced measurement times, and higher resolution compared to the traditional narrow-band scanning-type IXS spectrometers. The theory of x-ray echo spectrometers presented earlier [Yu. Shvyd'ko, Phys. Rev. Lett. 116, 080801 (2016)] is developed here further with a focus on questions of practical importance, which could facilitate optical design and assessment of the feasibility and performance of the echo spectrometers. Among others, the following questions are addressed: spectral resolution, refocusing condition, echo spectrometer tolerances, refocusing condition adjustment, effective beam size on the sample, spectral window of imaging and scanning range, impact of the secondary source size on the spectral resolution, angular dispersive optics, focusing and collimating optics, and detector's spatial resolution. Examples of optical designs and characteristics of echo spectrometers with 1-meV and 0.1-meV resolutions are presented.
Antenna Array Manifolds for High-Resolution Direction Finding

The antenna array manifold is central to high-resolution direction finding. The analytic manifold is defined here as the mathematical model of the array response calculated by solving the electromagnetic equations for the waves impinging on the array. Array manifolds commonly used in the array signal processing literature are approximations of the analytic manifold. This paper describes the characteristics of the analytic manifold and compares it with commonly used approximate manifolds. The impact of these approximations on the performance of direction-of-arrival estimation in challenging superresolution scenarios is evaluated by selected numerical examples.
Imperiled Women and Chivalrous Men in Colonial India, 1757–1857

This essay examines some landmark moments in a hundred year period with a view to uncovering the relationship between the trope of the imperiled woman and the consolidation of British colonial powe...
The Brittle to Ductile Transition and the Transmission of Slip across Grain Boundaries in L12 Intermetallic Compounds

It is argued that the improvement in the ductility of Ni3Al, Ni3Ga, Ni3Si and Ni3Ge through the addition of boron (in the ppm range) and of Zr3Al through fast neutron irradiation is related to an increase in the transmission of slip across the grain boundaries. The transmittal mechanism is dislocation nucleation at the heads of pile-ups, and this is made easier through the disordering of the boundaries. The evidence supporting this view is reviewed. It is suggested that grain boundary disorder may be a general requirement for ductility.
The phase interrogation method for optical fiber sensor by analyzing the fork interference pattern

The phase interrogation method for optical fiber sensor is proposed based on the fork interference pattern between the orbital angular momentum beam and plane wave. The variation of interference pattern with phase difference between the two light beams is investigated to realize the phase interrogation. By employing principal component analysis method, the features of the interference pattern can be extracted. Moreover, the experimental system is designed to verify the theoretical analysis, as well as feasibility of phase interrogation. In this work, the Mach–Zehnder interferometer was employed to convert the strain applied on sensing fiber to the phase difference between the reference and measuring paths. This interrogation method is also applicable for the measurements of other physical parameters, which can produce the phase delay in optical fiber. The performance of the system can be further improved by employing highlysensitive materials and fiber structures.
Epidemiology of Microwave Radiation Effects in Humans

Microwave radiation is a form of nonionizing electromagnetic radiation of very low photon energies. Formerly part of the radiofrequency portion of the electromagnetic spectrum, it has been arbitrarily separated out and lies between infrared radiation and the radiofrequencies. Microwave radiation is generally defined as that portion of the electromagnetic spectrum between frequencies of 300 megahertz (MHz) and 300 gigahertz (GHz) associated with wavelengths between one meter and one millimeter (WHO, 1981) (Fig. 1). Microwaves have been subdivided into frequency bands designated loosely as extremely high frequency (EHF) or millimeter waves, super high frequency (SHF) or centimeter waves, and ultrahigh frequency (UHF) or decimeter waves. In addition there are letter designations (such as S,K,X,P) for special frequency bands which are used for radar (radio detecting and ranging), and there are industrial, scientific and medical (ISM) bands which have been assigned for specific applications, according to international agreements.
Red/LeD: An Asymptotically Optimal and Scalable Online Algorithm for Service Caching at the Edge

Edge servers, which are small servers located close to mobile users, have the potential to greatly reduce delay and backhaul traffic of mobile Internet applications by moving cloud services to the edge of the network. Due to limited capacity of edge servers and dynamic request arrival, proper service caching at the edge is essential to guarantee good performance. This paper proposes a tractable online algorithm called retrospective download with least-requested deletion that caches services dynamically without any assumptions on the arrival patterns of mobile applications. We evaluate the competitive ratio of our policy, which quantifies the worst case performance in comparison to an optimal offline policy. We prove that the competitive ratio of our policy is linear with the capacity of the edge server. We also show that no deterministic online policy can achieve a competitive ratio that is asymptotically better than ours. Moreover, we prove that our policy is scalable, in the sense that it only needs doubled capacity to achieve a constant competitive ratio. The utility of our online policy is further evaluated on real-world traces. These trace-based simulations demonstrate that our policy has better, or similar, performance compared with many intelligent offline policies.
IMPRINTING OR INSTITUTIONALIZATION? EXAMINING HOW SOCIAL CAPITAL IS TRANSFERRED DURING FOUNDER-CEO SUCCESSIONS

This study examines whether or not the perpetuation of an outgoing Founder-CEO’s social capital can be best explained by the theoretical notion of imprinting or institutionalization. Imprinting logic argues that the founder’s social capital will persist independent of whether or not the organization takes action to capture it. Institutionalization logic argues that the organization can replicate and revise the existing structure in an effort to capture the valuable social capital. Data was collected through interviews and case studies to understand how these logics manifest themselves in 38 venture-back companies. The data provide novel insights into the boundary conditions of the imprinting and institutionalization logics in regards to the transfer of a Founder-CEO’s social capital in a venture-backed startup undergoing its first succession.
The Limits of Knowledge; Mathematics and Methodological Principles

The limits of knowledge are determined by the world, by the apparatus the investigator brings to bear on problems, and the cognitive values and methods that govern the objectives of the process of inquiry. There is little we can say about the world per se Kant was right to emphasize. The position I start from here is that what is of epistemological interest is not the way the world is, but (a) the character of the inquiry as determined by the goals, values and methods of the inquirers,32 and (b) the way the world is believed to be.
The inviability, weakness, and sterility of interspecific hybrids.

Publisher Summary In this chapter, the review of available data clearly points to the conclusion that the causes underlying the erection of barriers of reproductive isolation, therefore of the origin of species, differ considerably from one group of organisms to another. Furthermore, these differences are related to other differences among groups of organisms, such as size and structure of populations, rates of reproduction, and methods of adaptation. In the future, therefore, the study of the origin of species should not be a search for any more general causes, which might be considered as responsible for speciation in all groups of organisms, but a series of special and comparative investigations, by means of which the interrelationships mentioned above, as well as others as yet unknown, can be further explored and more firmly established.
Fully Integrated MCM Microfluidic System for DNA Analysis

A fully integrated and self-contained microfluidic multi-chip modular (MCM) device having sample-to-answer capability was developed. The device performs complete genetic analysis, including sample preparation (i.e., target cell capture, cell purification/concentration, cell lysis, DNA amplification) and microarray detection.
IMiDs New and Old.

IMiDs are a class of biologic agents with immunomodulatory, anti-angiogenic, and direct anti-cancer activities. This review summarizes current data on clinical development and application of IMiDs in non-Hodgkin lymphoma (NHL) subtypes, focusing primarily on lenalidomide, with additional discussion on managing common side effects. Improved upon the prototype thalidomide, the second-generation compound lenalidomide has enhanced immunological and anti-cancer properties with fewer side effects, while next-generation small molecule cereblon/E3 ubiquitin ligase modulator CC-122 is in early clinical studies. Lenalidomide is FDA-approved for treatment of relapsed/refractory mantle cell lymphoma as a single agent, as well as in combination with rituximab for R/R follicular lymphoma and marginal zone lymphoma. In addition, numerous clinical trials of lenalidomide, as single agent, in combination with anti-CD20 antibodies, or in combination with chemoimmunotherapy regimens, have shown promise in aggressive and indolent NHL in both the upfront and relapsed/refractory setting. As clinical trials with lenalidomide continue to find success in both indolent and aggressive lymphomas, IMiDs are poised to be important building blocks for combinatorial strategies with antibodies, chemotherapy, novel target agents, and emerging immunotherapy involving immune checkpoint inhibitors and chimeric antigen receptor T cell (CAR-T) therapy. Delineation of treatment-specific and disease-specific biomarkers is an important research objective to gain insight into potential mechanisms of action, and to guide future clinical development.
100 – Exact Equations

Publisher Summary This chapter discusses exact equations. The concept is applicable to quasi-linear partial differential equations, and yields an exact solution. Some quasi-linear partial differential equations can be integrated directly. The procedure considers the quasi-linear partial differential equation M(x, y, u)ux = N(x, y, u)uy. If this equation satisfies the exactness condition Mx = Ny, then an implicit solution to M(x, y, u)ux = N(x, y, u)uy will be given by Φ(x, y, u) = 0, where M = Φy, N = Φx. To determine the function Φ, the equation M = Φy is integrated to obtain Φ = ∫Mdy + g(x, u). Using N = Φx gives ∫Mxdy + gx(x, u) = N.
Laboratory diagnosis of EBV infection in children

Epstein-Barr virus (EBV) remains one of the most important pathogens in children, which usually causes acute EBV infection, chronic active EBV infection, hemophagocytic lymphohistiocytosis, lymphoma and other cancers. Therefore, effective laboratory diagnosis is of importance in diagnosis, surveillance, and control of EBV-associated disease. Currently, a variety of detection methods have been applied in clinical laboratories and typical diagnostic assays are always focusing on EBV-DNA and serological tests. Different assays vary in different purposes and applications, which seems to be difficult to choose an appropriate technique. This article aims at systematically analyzing clinical significance of these assays and evaluating the immune functions of EBV infection and the detection of susceptibility genes of EBV-related disease. (Chin J Lab Med, 2015, 38: 223-225) Key words: Epstein-barr virus infections; Viral load; Clinical laboratory techniques
DOT1L-controlled cell-fate determination and transcription elongation are independent of H3K79 methylation

Actively transcribed genes in mammals are decorated by H3K79 methylation, which is correlated with transcription levels and is catalyzed by the histone methyltransferase DOT1L. DOT1L is required for mammalian development, and the inhibition of its catalytic activity has been extensively studied for cancer therapy; however, the mechanisms underlying DOT1L's functions in normal development and cancer pathogenesis remain elusive. To dissect the relationship between H3K79 methylation, cellular differentiation, and transcription regulation, we systematically examined the role of DOT1L and its catalytic activity in embryonic stem cells (ESCs). DOT1L is dispensable for ESC self-renewal but is required for establishing the proper expression signature of neural progenitor cells, while catalytic inactivation of DOT1L has a lesser effect. Furthermore, DOT1L loss, rather than its catalytic inactivation, causes defects in glial cell specification. Although DOT1L loss by itself has no major defect in transcription elongation, transcription elongation defects seen with the super elongation complex inhibitor KL-2 are exacerbated in DOT1L knockout cells, but not in catalytically dead DOT1L cells, revealing a role of DOT1L in promoting productive transcription elongation that is independent of H3K79 methylation. Taken together, our study reveals a catalytic-independent role of DOT1L in modulating cell-fate determination and in transcriptional elongation control.
Abstract 16915: Potential Role of Endothelial Cell WWOX in the Pulmonary Vascular Response to Hypoxia

Introduction: Pulmonary arterial hypertension (PAH) is characterized by abnormal proliferation and dysfunction of pulmonary artery smooth muscle and endothelial cells (PASMC, PAEC). The WWOX/ Wwox ...
Kecemasan Mahasiswa STT Bethel Indonesia terhadap Covid-19

This study aims to obtain information about the psychological impact of anxiety caused by Covid-19 on STTBI students. Method The approach used in this research is the quantitative method is the activity of collecting data, processing, analyzing, and presenting data based on the amount carried out objectively which aims to solve a problem. The method in this research is a descriptive research method using a quantitative approach. In quantitative research, the main criteria for research data are valid, reliable, and objective. The study population was 40 STTBI students and 30 students as samples. Based on data analysis, which uses the formula for the average score of students obtained using a Likert scale questionnaire. Based on the calculation of the correlation test, it is found that the level of anxiety is 0.331 at the coefficient interval from 0.80 to 1.00. This shows that the level of anxiety from STTBI students is only 63.26%. Based on the results of the variable test, it is found that generally, students experience anxiety about the continuation of future studies, the negative stigma of society towards sufferers of Covid-19, worry about the condition of their parents. Abstrak Penelitian ini bertujuan untuk memperoleh informasi tentang dampak psikologis kecemasan yang ditimbulkan Covid-19 terhadap mahasiswa STTBI. Metode Pendekatan yang di-gunakan dalam penelitian ini adalah metode kuantitatif adalah kegiatan pengumpulan data, pengolahan, analisis, dan penyajian data berdasarkan jumlah yang dilakukan secara obyektif yang bertujuan untuk memecahkan suatu masalah. Metode dalam penelitian ini adalah metode penelitian deskriptif dengan menggunakan pendekatan kuantitatif. Dalam penelitian kuantitatif, kriteria utama terhadap data hasil penelitian adalah valid, reliabel, dan obyektif. Populasi Penelitian Ini Adalah Mahasiswa STTBI sebanyak 40 mahasiswa dan yang dijadikan sampel sebanyak 30 mahasiswa. Berdasarkan Analisis data yang mana menggunakan rumus rata-rata skor mahasiswa yang didapat dengan menggunakan angket skala likert. Berdasarkan Perhitungan uji korelasi diperoleh tingkat kecemasan sebesar 0.331 pada interval koefisien 0,80 – 1,00. Hal ini menunjukkan bahwa tingkat kecemasan dari mahasiswa STTBI hanya sebesar 63,26%. Berdasarkan Hasil uji variabel maka diperoleh umumnya mahasiswa mengalami kecemasan terhadap kelanjutan studi di masa depan, stigma negatif masyarakat terhadap penderita Covid-19, kuatir terhadap keadaan orang tua.
Sequencing and Phylogenetic Analyses of Structural and Accessory Proteins of Middle East Respiratory Syndrome Coronavirus from the First Imported Case in China,2015

To investigate the genetic character and origin of the first imported infection case of middle East respiratory syndrome coronavirus(named as MERS-CoV_China GD01),RNA was extracted from swabs of this patient followed by RT-PCR amplification.All coding gene of structural(S,E,M,E)and accessory(ORF3,ORF4 a,ORF4b,ORF5,ORF8b)proteins were sequenced and analyzed.Phylogenetic analyses of structural protein coding genes of MERS-CoV_China GD01 indicates that several substitutes exists in S coding gene and its origin belong group 5of MERS-CoV,which were recent circulated in Saudi Arabia area,while other three structural genes(N,E,M)were very conserved.Phylogenetic analyses of accessory protein coding genes of MERS-CoV_China GD01 indicates that several substitutes exists among ORF3,ORF4 a,ORF4band ORF5,while ORF8 b was conserved.In conclusion,genome of MERS-CoV_China GD01 was general conserved although several genetic variations were found among structural and accessory protein coding genes.This is the first report on sequencing and phylogenetic analyses of the first imported MERS case in China,which may pay the way for prevention and control of imported MERS-CoV infection.
Cross-site Epileptic Seizure Detection Using Convolutional Neural Networks

Automated epileptic seizure detection has been an active area of research for the last two decades. Yet few, if any, of these methods are used in clinical practice because they fail to generalize across different patient populations. We present three simple Convolutional Neural Network (CNN) architectures for seizure detection that are capable of generalizing across sites. The convolutional layers automatically learn robust and discriminative correlations directly from both the raw multichannel scalp electroencephalography (EEG) signal and its short-time spectral representation. The models are trained on the publicly available Children's Hospital of Boston (CHB) data set in a leave-one-patient-out cross validation strategy. The trained model is then tested on a data set recorded at the University of Wisconsin (UW). We demonstrate that our CNNs achieve higher sensitivity than competing baselines, with only a minor increase in false positive rate. To our knowledge, this is the first work to achieve inter-hospital seizure detection without a significant drop in performance, thus providing an important benchmark for the seizure detection field.
Abstract 2086: Differential immune-cell landscape in tissue and liquid biopsy specimens is associated with recurrence risk across meningioma methylation-subtypes

Background. Tumor-infiltrating immune cells can favor or inhibit tumor growth, constituting promising and alternative targets for treatment of patients with meningiomas (MNG), a prevalent primary intracranial tumor with no known therapy beyond surgery and radiation. Immune-cell composition can predict therapy response in other diseases, therefore, profiling immune-cell infiltrates in these tumors is crucial, preferentially by non-invasive approaches. Genome-wide methylation arrays are powerful tools to classify and assess cell composition either in tumor tissue or with liquid biopsy. Objective: We aim to apply methylation-based classifiers to estimate immune-cell composition of tumor tissue and serum specimens to predict recurrence-free survival in patients with MNG. Methods: We conducted unsupervised and supervised analyses of the methylome of a multicenter MNG cohort composed of 326 tissue, 60 serum and 9 control specimens. Immune-cell composition (B-cells, CD4-T & CD8-T cells, neutrophils, natural killer cells, and monocytes) and recurrence risk were estimated using methylation-based classifiers. We used the point-biserial correlation method to analyze associations across categorical clinical and molecular features. Results: We identified four distinct methylation subgroups of MNG (in serum or tissue) that presented a differential immune cell landscape composition. In the tissue, MNG methylation subgroups were mutually exclusive in enrichment or depletion of NK-, cytotoxic T- or monocyte-cell methylation signatures and in the serum, they were enriched of monocyte- and B-cell signatures. Distinct Immune-cell signatures (Monocytes, CD8T and Neutrophils) were correlated with risk of recurrence or grade in MNG tissue and/or liquid biopsy specimens. Conclusion: DNA methylation-based deconvolution allowed for the detection of differential immune-cell composition across MNG methylation-subtypes in tissue that could be detected in liquid biopsy specimens. Distinct immune-cell signatures correlated with MNG recurrence risk/grade (e.g. T-cell) in our cohort were reported to improve anti-tumoral immune response in many tumors. These results suggest that profiling tumor immune-cell landscape can inform tumor behavior and provide insight in application of existing and novel therapeutic approaches in MNG. Citation Format: Grayson A. Herrgott. Differential immune-cell landscape in tissue and liquid biopsy specimens is associated with recurrence risk across meningioma methylation-subtypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2086.
Notch2 suppression mimicking changes in human pulmonary hypertension modulates Notch1 and promotes endothelial cell proliferation.

This study demonstrates a previously unidentified role for Notch2 in the maintenance of lung vascular endothelial cell quiescence and pulmonary artery hypertension (PAH). A key novel finding is tha...
Proof schemes and learning strategies of above-average mathematics students

What patterns can be observed among the mathematical arguments above-average students find convincing and the strategies these students use to learn new mathematical concepts? To investigate this question, we gave task-based interviews to eleven female students who had performed well in their college-level mathematics courses, but who differed in the number of proof-oriented courses each had taken. One interview was designed to elicit expressions of what students find convincing. These expressions were categorized according to the proof schemes defined by Harel and Sowder (1998). A second interview was designed to elicit expressions of what strategies students use to learn a mathematical concept from its definition, and these expressions were classified according to the learning strategies described by Dahlberg and Housman (1997). A qualitative analysis of the data uncovered the existence of a variety of phenomena, including the following: All of the students successfully generated examples when asked to do so, but they differed in whether they generated examples without prompting and whether they successfully generated examples when it was necessary to disprove conjectures. All but one of the students exhibited two or more proof schemes, with one student exhibiting four different proof schemes. The students who were most convinced by external factors were unsuccessful in generating examples, using examples, and reformulating concepts. The only student who found an examples-based argument convincing generated examples far more than the other students. The students who wrote and were convinced by deductive arguments were successful in reformulating concepts and using examples, and they were the same set of students who did not generate examples spontaneously but did successfully generate examples when asked to do so or when it was necessary to disprove a conjecture.
A Review of “Restless Empire: China and the World since 1750”

Odd Arne Westad, the award-winning Cold War historian at the London School of Economics, is one of the finest chroniclers of modern China and its relations with the wider world. His 2003 book Decis...
Childhood obesity and community food environments in Alabama's Black Belt region

Background Childhood obesity has been rising rapidly in the USA. The rate is higher among those at a lower socioeconomic status and racial/ethnic minority groups. In Alabama, nearly half of the children from rural African American families are overweight or obese. Studies suggest that children's eating behaviours and weight could be influenced by surrounding food environments. The purpose of this paper is to assess the community food environment and examine the associations with childhood obesity in Alabama's Black Belt region. Methods This research uses both qualitative and quantitative methods. Weight status of 613 African American students in four elementary schools in a rural county of Alabama was assessed. We examined community food environments around children's home through GIS (Geographic Information System) and statistical methods. The interrelations between children's weight and community food environments are explored with multi-level models. Results Approximately 42.1% of surveyed children were overweight or obese, much higher than the national average, 30.6%. In Model 1, convenience stores (3.44; P < 0.01), full service restaurants (8.99; P < 0.01) and supermarkets (−37.69; P < 0.01) were significantly associated with the percentile of body mass index. Fast food stores (−0.93; P = 0.88) were not related to children's weight. In Model 2, the additions of sociodemographic factors and school effects cause significant changes of the relationships between children's weight and four types of food outlets. The percentage of African American population (90.23, P < 0.01) and school (6.68, P < 0.01) were positively associated with children's weight; while median household income (−39.6; P < 0.01) was negatively related to it. Conclusion Children's weight is influenced by community food environments, sociodemographic factors and school context. Findings suggest that policymakers and planners need to improve community food environments of low-income minority communities. Parents and schools should pay more attention to reduce the negative impacts of food environments on children.
Hierarchy of globin complexes. The quaternary structure of the extracellular chlorocruorin of Eudistylia vancouverii.

Abstract The molecular dimensions of the extracellular, hexagonal bilayer chlorocruorin of the polychaete Eudistylia vancouverii , determined by scanning transmission electron microscopy (STEM) of negatively stained specimens, were diameter of 27·5 nm and height of 18·5 nm. STEM mass measurements of unstained, freeze-dried specimens provided a molecular mass ( M m ) of 3480 ± 225 kDa. The chlorocruorin had no carbohydrate and its iron content was 0·251 ± 0·021 wt %, corresponding to a minimum M m of 22·4 kDa. Mass spectra and 1 nuclear magnetic resonance spectra of the prosthetic group confirmed it to be protoheme IX with a formyl group at position 3. SDS/polyacrylamide gel electrophoresis, reversed-phase chromatography and N-terminal sequencing suggested that the chlorocruorin consists of at least three chains of ~30 kDa and five chains of ~16 kDa; the two types of subunits occur in the ratio 0·26:0·74(± 0·08). Complete dissociation of the chlorocruorin at neutral pH in the presence of urea or guanidine hydrochloride, followed by gel filtration, produced elution profiles consisting of three peaks, B, C and D. Fractions B and C consisted of the ~16 kDa chains and fraction D consisted of the ~30 kDa subunits. Mass measurements of particles in STEM images of unstained, freeze-dried fractions B and C provided M m of 208 ± 23 kDa and 65 ± 12 kDa, respectively, in agreement with 191 ± 13 kDa and 67 ± 5 kDa obtained by gel filtration. Particles with M m = 221 + 21 kDa were also observed in STEM images of unstained, freeze-dried chlorocruorin. These results imply that the chlorocruorin structure, in addition to the ~30 kDa linker subunits that have 0·26 to 0·47 heme groups/chain, comprises ~65 kDa tetramers and ~200 kDa dodecamers (trimers of tetramers) of globin chains. The stoichiometry of the tetramer and linker subunits calculated from molar amino acid compositions was 34 ± 4 and 43 ± 9. The complete dissociation of the chlorocruorin was accompanied by a 50 to 75% loss of the 55 ± 14 Ca 2+ /mol protein, and was decreased to ~35 % by the presence of 10 to 25 m m -Ca 2+ . Reassociation of dissociated chlorocruorin was maximal in the presence of 2·5 to 5 m m -Ca 2+ . The dodecamer and/or tetramer subunits in the absence or presence of Ca 2+ exhibited very limited ( θ ] 222 of the tetramer and linker subunits were lower. Our results are compatible with a view of the quaternary structure of Eudistylia chlorocruorin as a hierarchy of globin complexes, wherein 66 to 75 % of the whole molecule is composed of 12 ~ 200 kDa dodecamers, each consisting of a trimer of tetramers of globin chains having an incomplete “myoglobin fold”. The dodecamers are linked into a hexagonal bilayer structure by 30 to 40 Ca 2+ and 30 to 40 heme-deficient, chimeric globin chains.
Anatomy of the sinus node, av node and os cordis of the beef heart.

The bovine sinus node is in a location similar to that in the human and canine hearts, but it contains no central large artery whereas the sinus node in the other two species is distinctly organized about such an artery. This suggests the bovine sinus node may function as a more primitive structure. The arterial supply of the bovine sinus node originates from the proximal left circumflex artery. The AV node and bundle are similar in all three species in location and internal anatomy. The human and bovine AV node and bundle are supplied by a single artery entering from the posterior wall of the heart, while the dog has an equally large branch to this region from the septal artery. The os cordis is a large constant bone lying near the junction of the interatrial and interventricular septa of the beef heart and extending anteriorly into the AV valve rings, especially the right. The AV node lies parallel to the os cordis on its right atrial side and the AV bundle courses beneath the bone. Possible functions of the os cordis are considered.
Character Development: Putting It Into Practice in Admissions and Instruction

AbstractThe most important knowledge and skills a college education should develop in young people are those underlying good character, such as integrity, responsibility, work ethic, intellectual curiosity, mental flexibility, and wisdom. When leaders fail, most frequently it is because of issues of character, not lack of knowledge or intellectual abilities. This article describes how to put character development into practice in a university setting (Oklahoma State University) through admissions processes and through instruction via a track in ethical leadership. The article also describes the theory behind the innovations and also ways these innovations can be put into practice.
The origin of skin-stretch-caused motion artifacts under electrodes

The outside of the skin of the forearm is typically 15 mV more negative than the inside. Stretching the skin causes a reduction in the magnitude of this skin potential V, which we observe as a motion artifact delta V. We seek to determine the origin of this motion artifact by successively stripping 12 layers of the skin using Scotch Tape. Between each stripping we measure artifact delta V, 13 Hz impedance Z, and change in impedance delta Z. On the interior surface of the forearm, Z decreases with number of strippings. delta Z can be first either positive or negative, then is always negative and decreases linearly with Z. delta V first remains constant and then decreases with Z and delta Z. delta V and delta Z increase with stretch force following a logarithmic relationship. delta Z has a rectangular shape waveform, whereas the rising edge of delta V shows a fast followed by a slow component and its falling edge decays exponentially with a large time constant. We have expanded the model of Thakor and Webster to best fit the waveform of delta V and delta Z caused by stretch.
Formal ring of a cubic solid angle

Abstract A rational cubic form with real plane factors determines a solid angle for whose lattice points a formal ring can be constructed and can be made invariant under units. As in the first half of this work (in Volume 8 of this Journal), there is a finite basis for the invariant ring but peculiar effects occur in higher dimension. There might be, for instance, no minimal basis subdivision for the support polyhedron, and no cyclic basis, (simulating algebraic resolution difficulties in C 8 ). Furthermore, the support polyhedron is “flat” in some affine sense. Cases are computed for small discriminant cubics.
Divorce, Family Structure, and the Academic Success of Children

* Foreword * Preface * Acknowledgments * Chapter 1. Historical Background of the Study * Chronological Highlights * Historical and Contemporary Facts Regarding Family Structure * Chapter 2. Research Regarding the Effects of Family Structure on Children * The Effects of Divorce on Academic Achievement: Research Results * The Effects of Remarriage Following Divorce on Academic Achievement * The Emotional and Psychological Effects of Divorce on Children * Circumstances That Can Influence the Effects of Divorce * The Influence of Time on the Effects of Divorce * The Effects of Divorce by Race * Chapter 3. Methodological Issues in Research on Divorce and Family Structure * Theory and Research Literature * Relevant Research Syntheses and Meta-Analyses * Methods * Models * Chapter 4. The Problems with Using Socioeconomic Status in Research * The Importance of Using SES Variables * The Issue of Causality * Predisruption versus Postdisruption Variables * Chapter 5. Problems Involving Analysis of Socioeconomic Status * Predisruption SES Variables * Results Using the Postdisruption SES Measures * Obtaining Effects for Divorce Using a Predisruption Control for SES * Discussion * Chapter 6. Determining the Effects for Remarriage * Results for Study Number 1 * Discussion * Results for Study Number 2 * Discussion * Chapter 7. Remarriage and Mobility * Hypotheses and Analyses Undertaken * Results * Discussion * Chapter 8. The Effects of Living with Neither Parent on Academic Achievement * Results * Discussion * Chapter 9. The Effects of the Most Common Family Structures on Academic Achievement * Theoretical Framework * Family Structure Variables * Discussion * Chapter 10. Longitudinal Analysis of the Effects of Remarriage Following Divorce on Academic Achievement * Methods and Data Sources * Models * Results * Discussion * Chapter 11. Testing Other Important Hypotheses * The Proper Category Hypothesis * Custodial Parent's Gender Hypothesis * The Distinction Hypothesis * Chapter 12. What Does It All Mean? * Consequences of Underestimating Influence of Family Structure * Sensitizing Educators to the Challenges of Children from Nontraditional Families * Alternative Ways to Control for SES * Summary * References * Index
Cytogenetic analysis of 120 primary pediatric brain tumors and literature review

We report chromosome results from 108 pediatric central nervous system (CNS) tumors. From our data and those in the literature we found that (1) cerebellar and low-grade astrocytic tumors, including gangliogliomas, are most often karyotypically normal; (2) supratentorial tumors were more frequently high-grade tumors that demonstrated a complex karyotype. Chromosome abnormalities were similar to those described in adult astrocytic tumors, namely, +7, 9p abnormalities, and -10; (3) primitive neuroectodermal tumors (PNETs) were virtually always karyotypically abnormal with a high frequency of +7, -8, i(17q), and -22. PNETs with -22 may represent a subset of tumors; (4) typical choroid plexus papillomas showed a normal karyotype, atypical papillomas showed a hyperdiploid karyotype (with +7, +12, and +20), choroid plexus carcinomas showed a hyperhaploid karyotype; (5) a few ependymomas showed hyperdiploidy or hypertetraploidy; (6) germ cell tumors showed complicated karyotypes; (7) monosomy 22 or 22q abnormalities appear to be a recurring finding in the malignant rhabdoid tumors; and (8) meningiomas showed -22 or 22q abnormalities associated with a complex karyotype. In general, in pediatric CNS tumors the least differentiated neoplasms have the greatest number of cytogenetic abnormalities. However, our present morphologic criteria for tumor diagnosis do not always correlate with a consistent karyotype, and further study of pediatric brain tumor morphology, site, behavior, and karyotype is required.
Duration of retinogenesis: its relationship to retinal organization in two cricetine rodents.

The Mongolian gerbil (Meriones unguiculatus) has a prolonged period of development relative to other muroid rodents. We have explored the consequences of this relatively long period of maturation on retinal cell number and topography by comparing the duration and topography of neurogenesis in the gerbil retina with that of a closely related species which develops rapidly, the Syrian hamster (Mesocricetus auratus) (Sengelaub et al.: J. Comp. Neurol. 246:527–543, 1986). An analysis of thymidine-labeled retinas indicate that cells destined for the gerbil retinal ganglion cell layer are generated for at least 12 embryonic days, twice the duration in the hamster. The period of cell loss in the gerbil retinal ganglion cell layer extends for at least 14 postnatal days, more than twice as long as in the hamster. The gerbil retina is generated in a center-to-periphery gradient for both retinal ganglion cells and displaced amacrine cells, while no such gradients are evident in the hamster retina. We conclude that the longer developmental period of the gerbil is associated with (1) a longer period of neurogenesis resulting in greater retinal cell number, (2) the expression of spatial gradients in neurogenesis, and (3) a larger eye at maturity. The last two factors, in part, may be related to the development of a highly differentiated area centralis and visual streak in the retina of this rodent. Unrelated to duration of growth, early differences in retinal shape between these two species contributes to the development of retinal topography. The gerbil, but not the hamster retina, is initially asymmetric, longer in its nasotemporal than its dorsoventral dimension. The gerbil retina then grows asymmetrically producing a spherical retina, and coincident in time, a nasotemporally extended visual streak.
Extraterrestrial 3He as a tracer of marine sediment transport and accumulation

THE deposition rate of deep-sea sediments, and their focused redeposition by deep-sea currents, can be evaluated from analyses of sedimentary 230Th with a temporal resolution limited only by bioturbation6,7,10,11. 230Th is produced uniformly throughout the ocean by radioactive decay of dissolved 234U and is removed sufficiently fast by sorption onto sinking particles to act as a 'constant-flux' tracer of sedimentation rates. But the half-life of 230Th (75 kyr) limits its use for this purpose to the past 200–250 kyr. Here we explore the use of extraterrestrial 3He from interplanetary dust particles1–4 (IDPs) as a constant-flux proxy that is free from this limitation. A comparison of 3He with 230Th in two cores from the equatorial Pacific Ocean indicates that the variability in the mean flux of IDPs over the past 200 kyr is less than 75%. But in contrast to this relatively constant rate of supply of 3He to the deep sea, the local burial rates of 3He and 230Th have varied by a factor of five over the past 450 and 200 kyr, respect-ively. We interpret this variability as reflecting sediment focusing, with a temporal pattern that suggests regular cycles of climate-driven reorganization of near-bottom currents in the deep Pacific Ocean.
Coordination-dependent surface atomic contraction in nanocrystals revealed by coherent diffraction

Surface atoms have fewer interatomic bonds than those in the bulk that they often relax and reconstruct on extended two-dimensional surfaces. Far less is known about the surface structures of nanocrystals. Here, we show that coherent diffraction patterns recorded from individual nanocrystals are very sensitive to the atomic structure of nanocrystal surfaces. Nanocrystals of Au of 3-5 nm in diameter were studied by examining diffraction intensity oscillations around the Bragg peaks. Both results obtained from modelling the experimental data and molecular dynamics simulations strongly suggest inhomogeneous relaxations, involving large out-of-plane bond length contractions for the edge atoms (approximately 0.2 A); a significant contraction (approximately 0.13 A) for {100} surface atoms; and a much smaller contraction (approximately 0.05 A) for atoms in the middle of the {111} facets. These results denote a coordination/facet dependence that markedly differentiates the structural dynamics of nanocrystals from bulk crystalline surfaces.