cssi/SciSciGPT-SciSciNet huggingface dataset:
Reduced-Bias Co-trained Ensembles for Weakly Supervised Cyberbullying Detection

Social media reflects many aspects of society, including social biases against individuals based on sensitive characteristics such as gender, race, religion, physical ability, and sexual orientation. Machine learning algorithms trained on social media data may therefore perpetuate or amplify discriminatory attitudes against various demographic groups, causing unfair decision-making. One important application for machine learning is the automatic detection of cyberbullying. Biases in this context could take the form of bullying detectors that make false detections more frequently on messages by or about certain identity groups. In this paper, we present an approach for training bullying detectors from weak supervision while reducing the degree to which learned models reflect or amplify discriminatory biases in the data. Our goal is to decrease the sensitivity of models to language describing particular social groups. An ideal, fair language-based detector should treat language describing subpopulations of particular social groups equitably. Building on a previously proposed weakly supervised learning algorithm, we penalize the model when discrimination is observed. By penalizing unfairness, we encourage the learning algorithm to avoid unfair behavior in its predictions and achieve equitable treatment for protected subpopulations. We introduce two unfairness penalty terms: one aimed at removal fairness and another at substitutional fairness. We quantitatively and qualitatively evaluate the resulting models’ fairness on a synthetic benchmark and data from Twitter comparing against crowdsourced annotation.
MIDWALL STRESS-SHORTENING RELATIONS IN AORTIC STENOSIS PROGRESSION: MECHANISTIC INSIGHT INTO THE “DOUBLE- LOADED LEFT VENTRICLE”

The advent of TAVR has stimulated more focus on aortic stenosis (AS) in patients, most of whom have antecedent hypertension (HTN) and concentric remodeling. The purpose of this study was to evaluate midwall shortening (FSmw) among patients who developed severe AS. Prior work has shown that FSmw
The Association of Direct Observation of Medical Students With Patient-Centered Care for Obesity.

BACKGROUND AND OBJECTIVES Teaching medical students patient-centered approaches to weight loss counseling occurs in myriad ways. We examined lectures and direct faculty observation to see which was associated with better patient-centered care in medical students, measured by both self-perception and independent observer evaluation. METHODS Third- and fourth-year students attending one medical school were surveyed regarding their education in (1) weight loss and health behavior counseling, (2) obesity stigma, and (3) whether they had experienced direct faculty observation of their weight loss counseling. Several weeks later, the students were observed during a standardized patient encounter for obesity and an obesity-relevant comorbidity. A postencounter survey assessed overall student satisfaction with the encounter and with the care they provided. Independent coders rated their patient-centered communication using a validated measure. RESULTS There was no consistent association between any dependent variable and student ratings of adequacy of instruction, nor with instructional content. Direct faculty observation was not associated with overall encounter satisfaction or their overall patient-centeredness. However, experiences with direct faculty observation were significantly and positively associated with students' perceptions of patient engagement (b=0.1, P=.05), and with independent coders' ratings of student friendliness (b=0.13, P=.01), responsiveness (b=0.113, P=.03), and lower student anxiety (b=-0.1, P=.01). CONCLUSIONS Independent observation and self-report of instruction adequacy and content had no consistent association with care quality. However, direct faculty observation predicted improvement in both student self-reports and independent observer ratings of students' interpersonal quality of care. Further work is needed to define optimal methods of imparting patient-centered care.
Decay Scheme of Tb 158

A study has been made of the decay of $^{158}\mathrm{Tb}$, including measurements of transition intensities, lifetimes of excited states, and angular correlations. The resulting decay scheme is generally in agreement with that proposed in previous studies. Major modifications include a new level at 819 keV in $^{158}\mathrm{Dy}$, and several new $\ensuremath{\gamma}$-ray transitions which were seen in coincidence studies and which may be due to a long-lived isomeric state in $^{158}\mathrm{Tb}$. Also, improvement was attained in the precision of the intensities of several weak $\ensuremath{\gamma}$-ray transitions, and of the $\ensuremath{\beta}$-branching ratio. The lifetimes of the first ${2}^{+}$ states in $^{158}\mathrm{Gd}$ and $^{158}\mathrm{Dy}$ were redetermined for several different cascades through $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ as well as $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence-delay studies; the values measured were, respectively, 2.59\ifmmode\pm\else\textpm\fi{}0.10 and 1.76\ifmmode\pm\else\textpm\fi{}0.10 nsec. The 1188-keV state and the 1107-keV $\ensuremath{\gamma}$-ray transition in the decay to $^{158}\mathrm{Gd}$ were confirmed to be, respectively, a ${2}^{+}$ state and an $E2$ transition through an angular-correlation measurement. These modifications and improvements in the decay scheme are discussed on the basis of the rotational model of deformed nuclei.
Measures of adherence as predictors of early and total weight loss with intensive behavioral therapy for obesity combined with liraglutide 3.0 mg.

Abstract Individual weight loss outcomes with intensive behavioral therapy (IBT) for obesity are variable. The present study assessed whether visit attendance, dietary self-monitoring, medication, and meal-replacement adherence were associated with 52-week weight loss with IBT and tested whether these relationships were independent of associations with early weight loss. This was a secondary analysis of a randomized trial in which 150 participants (76.1% female, 55.8% white, BMI = 38.8 ± 4.8 kg/m2) received either IBT alone, IBT with liraglutide 3.0 mg/d, or IBT-liraglutide combined with a 12-week meal replacement diet (Multi-component). In the full sample, visit attendance accounted for 14.8% of the variance in 52-week weight loss and dietary self-monitoring added 14.9%. Only self-monitoring was independently associated with weight loss. In the 100 liraglutide-treated participants, medication adherence accounted for an additional 9.9% of the variance in 52-week weight loss, and both self-monitoring and medication adherence were independent correlates. For the 50 Multi-component participants, meal replacement adherence did not predict weight loss. Early weight loss was associated with higher early and subsequent session attendance and dietary self-monitoring. However, self-monitoring and medication adherence remained important correlates of total weight loss when controlling for this variable. Strategies that help improve self-monitoring consistency and medication usage could improve weight loss with IBT.
Yin/Yang Epistemology

Traditional Chinese thought pays a great deal of attention to issues in ethics, but has very little to say about epistemology—at least by comparison with the enormous focus on issues about knowledge and justification one finds in Western philosophy during the modern period.
Perspectives on self-sampling for cancer screening among rural and urban women: Multilevel factors related to acceptability

PURPOSE Self-sampling tests may be used to overcome barriers to screening that are more prevalent in rural populations compared to urban populations. This study aims to qualitatively examine the attitudes toward established and novel self-sampling tests for cervical and colorectal cancer among women, comparing themes from rural versus urban areas. METHODS We recruited women (ages 45-65) from 28 counties in Pennsylvania. Four focus groups were conducted with women from metropolitan counties, and 7 focus groups were conducted with women from nonmetropolitan counties. A brief survey was conducted prior to the focus group regarding general health and willingness to complete self-sampling tests for cervical and colorectal cancer. FINDINGS We identified 3 themes about the potential for self-sampling for cancer screening: advantages and disadvantages of self-sampling compared to traditional testing, impact of self-sampling on patient interactions with their health care providers/clinics, and implications for improving/worsening access to quality health care services. We detected differences in responses from rural versus urban participants in the potential impact of self-sampling for cancer screening. CONCLUSIONS There are several barriers and facilitators at the individual, interpersonal, and organizational levels that influence the feasibility of implementing self-sampling for cancer screening in routine clinical practice. Rural participants face unique barriers to cancer screening across all levels. These findings can be used to guide interventions aimed at increasing the use of self-sampling methods.
Does hydrostatic pressure influence lumpfish (Cyclopterus lumpus) heart rate and its response to environmental challenges

Studies on the effects of environmental changes with increasing depth (e.g. temperature and oxygen level) on fish physiology rarely consider how hydrostatic pressure might influence the observed responses. In this study, lumpfish (Cyclopterus lumpus, 200-400 g), which can exhibit vertical migrations of over 100 m daily and can be found at depths of 500 m or more, were implanted with Star-Oddi micro-HRT loggers. Then, their heart rate (fH) was measured in a pressure chamber when exposed to the following: (i) increasing pressure (up to 80 bar; 800 m in depth) at 10°C or (ii) increasing temperature (12-20°C), decreasing temperature (12 to 4°C) or decreasing oxygen levels (101-55% air saturation at 12°C) in the absence or presence of 80 bar of pressure. Additionally, we determined their fH response to chasing and to increasing temperature (to 22°C) at atmospheric pressure. Pressure-induced increases in fH (e.g. from 48 to 61 bpm at 12°C) were associated with hyperactivity. The magnitude of the rise in fH with temperature was greater in pressure-exposed vs. control fish (i.e. by ~30 bpm vs. 45 bpm between 5°C and 20°C). However, the relative increase (i.e. slope of the relationship) was not different between groups. In contrast, 80 bar of pressure eliminated the small (5 bpm) increase in fH when control fish were exposed to hypoxia. Exhaustive exercise and increasing temperature to 22°C resulted in a maximum fH of 77 and 81 bpm, respectively. Our research shows that pressure influences the fH response to environmental challenges and provides the first evidence that lumpfish have a limited capacity to increase fH.
Plasma Metabolic Phenotypes of HPV-Associated versus Smoking-Associated Head and Neck Cancer and Patient Survival.

Background: Metabolic differences between human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) and smoking-associated HNSCC may partially explain differences in prognosis. The former relies on mitochondrial oxidative phosphorylation (OXPHOS) while the latter relies on glycolysis. These differences have not been studied in blood. Methods: We extracted metabolites using untargeted liquid chromatography high-resolution mass spectrometry from pretreatment plasma in a cohort of 55 HPV-associated and 82 smoking-associated HNSCC subjects. Metabolic pathway enrichment analysis of differentially expressed metabolites produced pathway-based signatures. Significant pathways (P Results: Of 2,410 analyzed metabolites, 191 were differentially expressed. Relative to smoking-associated HNSCC, bile acid biosynthesis (P Conclusions: Plasma metabolites related to glycolysis and mitochondrial OXPHOS may be biomarkers of HNSCC patient prognosis independent of HPV or smoking. Future investigations should determine whether they predict treatment efficacy. Impact: Blood metabolomics may be a useful marker to aid HNSCC patient prognosis.
The Role of TGF-β in Bone Metastases.

Complications associated with advanced cancer are a major clinical challenge and, if associated with bone metastases, worsen the prognosis and compromise the survival of the patients. Breast and prostate cancer cells exhibit a high propensity to metastasize to bone. The bone microenvironment is unique, providing fertile soil for cancer cell propagation, while mineralized bone matrices store potent growth factors and cytokines. Biologically active transforming growth factor β (TGF-β), one of the most abundant growth factors, is released following tumor-induced osteoclastic bone resorption. TGF-β promotes tumor cell secretion of factors that accelerate bone loss and fuel tumor cells to colonize. Thus, TGF-β is critical for driving the feed-forward vicious cycle of tumor growth in bone. Further, TGF-β promotes epithelial-mesenchymal transition (EMT), increasing cell invasiveness, angiogenesis, and metastatic progression. Emerging evidence shows TGF-β suppresses immune responses, enabling opportunistic cancer cells to escape immune checkpoints and promote bone metastases. Blocking TGF-β signaling pathways could disrupt the vicious cycle, revert EMT, and enhance immune response. However, TGF-β’s dual role as both tumor suppressor and enhancer presents a significant challenge in developing therapeutics that target TGF-β signaling. This review presents TGF-β’s role in cancer progression and bone metastases, while highlighting current perspectives on the therapeutic potential of targeting TGF-β pathways.
The E↵ect of Income Heterogeneity in An Experiment with Local and Global Public Goods

Public goods such as national defense or climate change mitigation affect people in multiple locations. We report on a linear public goods experiment, where subjects can contribute not only to a local public good but also to a global public good. We study the effects of endowment heterogeneity by comparing a setting where two localities have the same income (homogeneous treatment) with a setting where the localities differ in income (heterogeneous treatment). We find that: 1) social efficiency is higher in the homogeneous treatment than in the heterogeneous treatment; 2) the efficiency difference comes from two aspects: the shift from global to local public good contribution and lower total public goods provision in the heterogeneous treatment; and 3) inequality aversion and reciprocity play a role in contribution behavior in the heterogeneous treatment; however these social preferences do not fully counter the efficiency loss caused by the endowment heterogeneity. Our findings suggest that policy interventions may be necessary to increase social efficiency with heterogeneous wealth and multiple public goods.
Time-Accurate Implicit ALE Algorithm for Shared-Memory Parallel Computers

An unstructured grid matrix-free GMRES+LU-SGS scheme is used to simulate unsteady CFD problems with moving bodies. The method is applied on sharedmemory, cache-based parallel machines. A special grid renumbering technique is used for the parallelization rather than the traditional method of partitioning the computational domain. Moving mesh with recurrent remeshing models the body motion.
Improving the evaluation of new cancer treatments: challenges and opportunities

There are, at present, ten times more anticancer drugs being tested in clinical trials than there were 15 years ago. Many of the new classes of agents, however, are predicted to work in only small subpopulations of patients, target unconventional aspects of tumour development and interact with other agents in an unpredictable manner. How can clinical trials be re-designed to accommodate the new features of targeted anticancer drugs?
Prediction of crack growth direction for mode I/II loading using small-scale yielding and void initiation/growth concepts

Under the assumption that the processes which control the direction of crack growth in 2024-T3 aluminum are directly related to void initiation and growth, a theoretical framework is developed to predict the direction of crack growth. The basic premise of the framework is that, depending on the mode mixity of the remotely applied loading, either σ m /σeff or σeff triggers the nucleation and growth of voids hence, fracture. The theoretical development uses linear elastic assumptions and two terms in the asymptotic expansion to describe the stress field in the vicinity of the crack tip for a mixed-mode I/II ARCAN specimen. Predictions based on the theory indicate that: (a) the transition from Mode~I type to Mode~II type crack propagation can be accurately quantified, and (b) the direction of crack growth is reasonably well predicted for both types of crack propagation. In addition, a qualitative, but microstructurally based, physical rationale for the observed phenomena is presented.
Combining static and dynamic reasoning for bug detection

Many static and dynamic analyses have been developed to improve program quality. Several of them are well known and widely used in practice. It is not entirely clear, however, how to put these analyses together to achieve their combined benefits. This paper reports on our experiences with building a sequence of increasingly more powerful combinations of static and dynamic analyses for bug finding in the tools JCrasher, Check 'n' Crash, and DSD-Crasher. We contrast the power and accuracy of the tools using the same example program as input to all three. At the same time, the paper discusses the philosophy behind all three tools. Specifically, we argue that trying to detect program errors (rather than to certify programs for correctness) is well integrated in the development process and a promising approach for both static and dynamic analyses. The emphasis on finding program errors influences many aspects of analysis tools, including the criteria used to evaluate them and the vocabulary of discourse.
Quasi-Monte Carlo for integrands with point singularities at unknown locations

This article considers quasi-Monte Carlo sampling for integrands having isolated point singularities. It is usual for such singular functions to be approached via importance sampling. Indeed one might expect that very uniform sampling, such as QMC uses, should be unhelpful in such problems, and the Koksma-Hlawka inequality seems to indicate as much. Perhaps surprisingly, we find that the expected errors in randomized QMC converge to zero at a faster rate than holds for Monte Carlo sampling, under growth conditions for which 2 + e moments of the integrand are finite. The growth conditions do place constraints on certain partial derivatives of the integrand, but unlike importance sampling, they do not require knowledge of the locations of the singularities.
Learning disjunction of conjunctions

The question of whether concepts expressible as disjunctions of conjunctions can be learned from examples in polynomial time is investigated. Positive results are shown for significant subclasses that allow not only propositional predicates but also some relations. The algorithms are extended so as to be provably tolerant to a certain quantifiable error rate in the examples data. It is further shown that under certain restrictions on these subclasses the learning algorithms are well suited to implementation on neural networks of threshold elements. The possible importance of disjunctions of conjunctions as a knowledge representation stems from the observations that on the one hand humans appear to like using it andon the other, that there is circumstantial evidence that significantly larger classes may not be learnable in polynomial time. An NP-completeness result corroborating the latter is also presented.
Military power and politics in black Africa

Explores the nature of intervention, disengagement and the relationship between civilian and military institutions.
X-to-autosome expression and msl-2 transcript abundance correlate among Drosophila melanogaster somatic tissues

In Drosophila melanogaster, the male-specific lethal (MSL) complex has been studied extensively for its role in upregulating male X-linked genes. Recent advances in high-throughput technologies have improved our understanding of how the MSL complex mediates dosage compensation through chromosome-wide chromatin modifications. Most studies, however, have focused on cell line models that cannot reflect any potential heterogeneity of in vivo dosage compensation. Comparisons between cell line and organismal gene-level dosage compensation upregulation suggest the possibility of variation in MSL complex activity among somatic tissues. We hypothesize the degree, up to but not exceeding 2-fold, to which the MSL complex upregulates male X-linked genes varies quantitatively by tissue type. In this model, MSL complex abundance acts as a rheostat to control the extent of upregulation. Using publicly available expression data, we provide evidence for our model in Drosophila somatic tissues. Specifically, we find X-to-autosome expression correlates with the tissue-specific expression of msl-2 which encodes an essential male-specific component of the MSL complex. This result suggests MSL complex mediated dosage compensation varies quantitatively by tissue type. Furthermore, this result has consequences for models explaining the organismal-scale molecular and evolutionary consequences of MSL-mediated dosage compensation.
Turning on minds with computers in the kitchen: supporting group reflection in the midst of engaging in hands-on activities

How can we promote the kinds of reflection needed for deep and lasting learning and the development of disposition toward scientific reasoning in the context of an informal learning community? In our research, we've discovered that learners have a greater appreciation of what they are learning when we give them the goal of helping others outside their community. This appreciation is demonstrated by their willingness to jot down notes during activities and later write articles for an online cooking "magazine." The online cooking magazine has the potential to support learning and development of disposition toward scientific reasoning in several ways. It provides a place to hang scaffolding that promotes recognizing what's been learned, what led to successes, and how science contributed to those successes. It also provides a context for knowledge building in which learners create concrete artifacts they can share outside of the Kitchen Science Investigators community. We found that with computers in the kitchen and an online magazine to contribute to, participants were stopping and reflecting in ways that we had only seen previously when a facilitator was prompting them.
Genocide as Social Control

Genocide is defined here as organized and unilateral mass killing on the basis of ethnicity. While some have focused on genocide as a type of deviance, most genocide is also social control—a response to behavior itself defined as deviant. As such, it can be explained as a part of a general theory of social control.Black's (1998)theories of social control explain the handling of conflicts with their social geometry—that is, with the social characteristics of those involved in the conflict. Here, Blackian theories of social control are extended to specify the social geometry of genocide as follows: genocide varies directly with immobility, cultural distance, relational distance, functional independence, and inequality; and it is greater in a downward direction than in an upward or lateral direction. This theory of genocide can be applied to numerous genocides throughout history, and it is capable of ordering much of the known variation in genocide—such as when and where it occurs, how severe it is, and who participates.
Anemia associated with changes in iron and iron-59 utilization in copper deficient rats fed high levels of dietary ascorbic acid and iron

The influence of dietary copper, iron, and ascorbic acid on iron utilization was examined in a 2×2×2 factorial experiment. Male Sprague-Dawley weanling rats were fed copper-deficient (Cu-, 0.42 μg Cu/g) or copper-adequate (Cu+, 5.74 μg Cu/g) diets that contained one of two levels of iron (38 or 191μg Fe/g) and ascorbic acid (0 or 1% of the diet). These eight diets were fed for 20 d, and rats received an oral dose of 4 μCi iron-59 on d 15. Compared to Cu+ rats, the Cu− rats had 27% lower hemoglobin levels with 45, 59, and 65% lower cytochrome c oxidase (CCO) activities in the liver, heart, and bone marrow, respectively (p<0.0001). High dietary iron or ascorbic acid did not alter hemoglobin in Cu+ rats. However, hemoglobin was 23% lower in Cu− rats fed the highest, rather than the lowest levels of iron and ascorbic acid. Liver CCO was decreased (p<0.02) in Cu− rats fed high iron. Among Cu− rats, ascorbic acid did not influence CCO but decreased hemoglobin by 17% (p<0.001), reduced the percentage of absorbed iron-59 in the erythrocytes by 91% (p<0.05) and depressed the percentage apparent absorption of iron (p<0.05). These results suggest that the effects of elevated dietary iron and ascorbic acid on iron utilization are influenced by copper status.
A method for rendering 3D finite element vector field solutions nondivergent

The use of the method of constraints for enforcing the zero divergence condition in vectorial finite-element schemes is discussed. An earlier implementation of the method was shown to produce the correct solution for a 3-D resonant cavity problem modeled by a single finite element. Partial success in extending the method to multielement cases is reported. The reduction in matrix size alone would justify the development of the technique for general multielement grids, but it will require the implementation of a global approach to the method of constraints. >
Plasmacytoid Urothelial Carcinoma, a Chemosensitive Cancer with Poor Prognosis, and Peritoneal Carcinomatosis

Purpose: Plasmacytoid urothelial carcinoma is a rare variant histology with poorly defined clinical behavior. We report clinical outcome information on patients with predominant plasmacytoid urothelial carcinoma.Materials and Methods: We retrospectively analyzed treatments and outcomes in patients with predominant plasmacytoid urothelial carcinoma seen at our institution from 1990 through 2010. The Kaplan-Meier method was used to calculate overall and progression-free survival.Results: We identified 31 patients with a median age of 63.5 years, of whom 83.3% were male. TNM stage was cT1N0 in 4 patients, cT2N0 in 7, cT3b-4aN0 in 5 and cT4b, N+ or M+ in 15. Median overall survival was 17.7 months (stage I–III vs IV 45.8 vs 13.3). Five of the 16 patients with potentially surgically resectable plasmacytoid urothelial carcinoma (pT4aN0M0 or less) received neoadjuvant chemotherapy, 10 underwent initial surgery and 1 was treated only with transurethral resection of bladder tumor. Despite pathological down staging...
Lest We Forget: Exhibiting (and Remembering) Slavery in African-American Museums

This study examines the dynamics of visual displays that portray African-American slavery across five black-centered museums. I argue that the rhetorics employed by black-centered sites are part of a racialized regime of representation. Taking lessons from the earlier pioneering efforts in museum practices, these black-centered sites are able to make significant contributions and frame the institution of slavery and the experience of enslavement within the tropes of survival, resistance, and achievement. Visual displays outlining slavery can be viewed as mechanisms by which cultural memory is induced as a tool for making meaning while collective identity in museums creates a space for investigating the relationship between the past and the present. Within exhibits that focus on slavery—and other events of the distant past—are contests over the utility of the past for present purposes.
Electro-Optic Measurements of PbS, PbSe, and PbTe

The band structures of the lead salts PbS, PbSe, and PbTe have been studied by electro-optic methods. Electroabsorption and electroreflectance measurements have been made over the energy ranges 0.25 to 0.65 eV and 0.6 to 5.5 eV, respectively, using an electrolyte to produce electric fields at the surface of these materials. An enhancement of the existing structure in absorption and reflection was generally observed, together with new structure apparently not related to formerly observed transitions. The analysis of these structures leads to the symmetry and energy of several transitions not previously seen. The experimental results are correlated with the band-structure calculations of Lin and Kleinman, and in general support their results.
Causal Paradoxes in Special Relativity

It has been argued that the existence of faster than light particles in the context of special relativity would imply the possibility to influence the past, and that this would lead to paradox. In this paper I argue that such conclusions cannot safely be drawn without consideration of the equations of motion of such particles. I show that such equations must be non-local, that they can be deterministic, and that they can avoid the suggested paradoxes. I also discuss conservation of energymomentum, and how instantaneous action at a distance can avoid similar paradoxes.
On estimating earnings functions for LDC's

A technique is developed for estimating earnings functions from data in which both wage earners and self-employed persons are included. The model analyzes labor earnings in a competitive market where self-employment is an important alternative to wage employment. This involves imputing the labor income of self-employed people as the wages they could otherwise earn as employees. The earnings function should be estimated from a pooled sample of both types of workers, since a sample of wage earners alone may not be random with respect to earnings-related characteristics. This may be done by including the share of self employment income in total earnings in the earnings function as an independent variable. Moreover, the coefficient of this new variable provides a basis for comparing the imputed wage of self employed persons with their total earnings. The procedure was found to be satisfactory for explaining the earnings of self employed persons with relatively low educational attainment. In Bangkok, self-employment and wage employment are alternative modes competing for the same labor; workers choose one or the other according to their relative earnings potential, and the market functions to equalize those potential earnings at the margin. 2 references.
Xenotransplantation of pancreatic and kidney primordia-where do we stand?

Abstract Lack of donor availability limits the number of human donor organs. The need for host immunosuppression complicates transplantation procedures. It is possible to ‘grow’ new pancreatic tissue or kidneys in situ via xenotransplantation of organ primordia from animal embryos (organogenesis of the endocrine pancreas or kidney). The developing organ attracts its blood supply from the host, enabling the transplantation of pancreas or kidney in ‘cellular’ form obviating humoral rejection. In the case of pancreas, selective development of endocrine tissue takes place in post-transplantation. In the case of kidney, an anatomically-correct functional organ differentiates in situ. Glucose intolerance can be corrected in formerly diabetic rats and ameliorated in rhesus macaques on the basis of porcine insulin secreted in a glucose-dependent manner by beta cells originating from transplants. Primordia engraft and function after being stored in vitro prior to implantation. If obtained within a ‘window’ early during embryonic pancreas development, pig pancreatic primordia engraft in non immune suppressed diabetic rats or rhesus macaques. Engraftment of pig renal primordia transplanted directly into rats requires host immune suppression. However, embryonic rat kidneys into which human mesenchymal cells are incorporated into nephronic elements can be transplanted into non-immune suppressed rat hosts. Here we review recent findings germane to xenotransplantation of pancreatic or renal primordia as a novel organ replacement strategy.
In vitro evidence for short-loop gonadotropin feedback on gonadotropin-releasing hormone neurons harvested from adult male rats.

GnRH neurons were harvested from adult male rats in order to determine if LH or FSH directly altered the modalities of GnRH release and/or cellular GnRH content. Cultures received vehicle, 25 ng/ml LH, 125 ng/ml LH, 25 ng/ ml FSH, or 125 ng/ml FSH, and media samples were collected before treatment, during the treatment pulse, and at 24 h post treatment; cellular GnRH content was determined 48 h post treatment. Both LH treatments used in this study acutely increased the frequency of spontaneous GnRH pulses and the mean media GnRH concentration. Further, neurons treated with an LH pulse exhibited large amplitude GnRH pulses during the treatment period. In contrast, FSH treatments had no effect on mean media GnRH concentrations and the 25 ng/ml FSH treatment did not alter neurosecretory modalities of spontaneous GnRH release. The neurons which received 125 ng/ml FSH did however exhibit large amplitude GnRH pulses during the gonadotropin pulse. This latter treatment was also associated with reduced cellular G...
An approximate method for estimating multiquantum transition probabilities in molecular collisions

Abstract A simple algebraic formula is given to allow an estimation of multiquantum transition probabilities in molecular collisions from a knowledge of the one- and two-quantum probabilities. The result is based on a simple exponential form for the probabilities often used in the moment method of analysis. Reasonably accurate vibrational energy transition probabilities are obtained for collinear atom-diatom collisions.
Characteristics of Teacher-Student Discourse in Computer-Based Dialogue Journals: A Descriptive Study

Twenty-seven learning disabled students in grades four through six engaged in interactive journal writing with their teachers in seven resource rooms (special education pull-out programs). Dialogue journal writing took place by means of a microcomputer program, and was carried out over a two- to three-month period. Although journal writing requires a conversational style, the literature suggests this might be affected both by learning disabled students' social and communicative abilities and by teachers' predisposition to engage in evaluative, “recitation”-style interactions in the classroom.A variety of discourse features of the journals were analyzed. In general, students engaged appropriately in written interaction with their teachers, but the journals tended to be dominated by teachers. For example, teachers wrote more, asked more questions, and introduced more new topics, including more topics that led to extended sequences or topic chains. Analysis of teacher input suggested that teachers used more ...
INVESTIGATIONS ON THE MULTIPLE COMPONENTS OF COMMERCIAL HORSERADISH PEROXIDASE.

Abstract Investigations on the structure of horseradish peroxidase (donor: H 2 O 2 oxidoreductase, EC 1.11.1.7), including its amino acid and carbohydrate composition, are described. Commercial horseradish peroxidase preparations contain multiple components which can be separated by electrophoresis on starch. The major components have been purified and their properties compared; they do not differ significantly in size, absorption spectrum, enzymatic activity, or amino acid composition. Horseradish peroxidase contains the following sugars: glucose, galactose, mannose, arabinose, xylose, fucose and hexosamine.
Blood-brain barrier permeability to horseradish peroxidase in twitcher and cuprizone-intoxicated mice

The status of blood-brain barrier (BBB) permeability was investigated in the twitcher, an authentic murine model of globoid cell leukodystrophy (GLD, Krabbe disease) and cuprizone-intoxicated mice. Although extensive demyelination was noted in the CNS of both mice and additionally, macrophage infiltration was pronounced in the twitcher, BBB remained intact to horseradish peroxidase. Thus, the change of microenvironment caused by demyelination is not necessarily a responsible factor for increased BBB permeability in the inflammatory demyelinating conditions.
Effect of concentration on rheological properties of acid-hydrolyzed amylopectin solutions

Abstract Rheological properties are sensitive to variations in molecular structure and they are useful in developing structure–function relationships for systems of polysaccharides in solution. Intrinsic viscosities of acid-hydrolyzed Amioca starches in 90% DMSO/10% water were determined using a modified approach for polyelectrolytes. Double logarithmic plots of specific viscosity, ηsp, against coil overlap parameter, c[η], were made and trends in both the dilute and concentrated regimes were found to be similar to those seen with other polysaccharides. Dynamic frequency sweeps indicated that all acid-hydrolyzed starches in 90% DMSO/10% water exhibited dilute solution or liquid-like behavior with G″ higher than G′. A contradiction in classification of 6–12% starch dispersions was found with shear tests (concentrated) and small strain oscillatory tests (dilute).
Unconventional integration of the bla gene from plasmid pIT2 during ISlacZ/hah transposon mutagenesis in Pseudomonas aeruginosa PAO1.

The ISlacZ/hah transposon carried by pIT2 and derived originally from Tn5 has been a popular system in the generation of random insertion mutants of Pseudomonas aeruginosa. Using this system in the current study, two transconjugants were identified as conferring high levels of carbenicillin resistance. Analyses by gene complementation tests and site-specific gene knockout experiments support the conclusion that carbenicillin resistance in these two mutants is not due to the insertion of ISlacZ/hah transposon into the affected genes. Instead, the production of a TEM β-lactamase was detected, and integration of the bla gene from pIT2 to the chromosome of the recipient strain was confirmed by polymerase chain reaction. This surprising event was reproducible, with an estimated frequency among the transconjugants of 4% to 10%, and it may cause a potential complication in the interpretation of mutant phenotypes without notice.
Effect of ascorbic acid on neurochemical, behavioral, and physiological systems mediated by catecholamines

Abstract Ascorbic acid, at concentrations below that normally present in the brain, inhibited the dopamine-sensitive adenylate cyclase in vitro . Ascorbate had no effect on the norepinephrine-sensitive adenylate cyclase. To study the in vivo effect of ascorbic acid on central dopaminergic systems, mice (C57 B1/6J) were injected with pharmacological doses (2 g/kg) of ascorbate, which produced a significant elevation in brain ascorbate concentration. Injecting the mice with ascorbate (2 g/kg) blocked the amphetamine-induced (15 mg/kg) increase in stereotype behavior which has been reported to be mediated by dopaminergic neural systems. Ascorbate had no effect on the amphetamine-induced locomotor activity thought to be mediated by norepinephrine systems. Ascorbate (1 g/kg) attenuated apmorphine-induced hypothermia in this same strain of mice. This demonstrates the specific neurochemical, physiological, and behavioral alterations in dopaminergic systems produced by ascorbic acid and suggests possible therapeutic uses for ascorbate in conditions involving functional dopamine excess.
Acute and Chronic Changes in Aquaporin 4 Expression After Spinal Cord Injury

The effect of spinal cord injury (SCI) on the expression levels and distribution of water channel aquaporin 4 (AQP4) has not been studied. We have found AQP4 in gray and white matter astrocytes in both uninjured and injured rat spinal cords. AQP4 was detected in astrocytic processes that were tightly surrounding neurons and blood vessels, but more robustly in glia limitans externa and interna, which were forming an interface between spinal cord parenchyma and cerebrospinal fluid (CSF). Such spatial distribution of AQP4 suggests a critical role that astrocytes expressing AQP4 play in the transport of water from blood/CSF to spinal cord parenchyma and vice versa. SCI induced biphasic changes in astrocytic AQP4 levels, including its early down-regulation and subsequent persistent up-regulation. However, changes in AQP4 expression did not correlate well with the onset and magnitude of astrocytic activation, when measured as changes in GFAP expression levels. It appears that reactive astrocytes began expressing increased levels of AQP4 after migrating to the wound area (thoracic region) two weeks after SCI, and AQP4 remained significantly elevated for months after SCI. We also showed that increased levels of AQP4 spread away from the lesion site to cervical and lumbar segments, but only in chronically injured spinal cords. Although overall AQP4 expression levels increased in chronically-injured spinal cords, AQP4 immunolabeling in astrocytic processes forming glia limitans externa was decreased, which may indicate impaired water transport through glia limitans externa. Finally, we also showed that SCI-induced changes in AQP4 protein levels correlate, both temporally and spatially, with persistent increases in water content in acutely and chronically injured spinal cords. Although correlative, this finding suggests a possible link between AQP4 and impaired water transport/edema/syringomyelia in contused spinal cords.
Effects of Contraphysiologically Administered Diethylstilbestrol on the Menstrual Cycle1

Numerous workers have reported that the intermenstrual administration of hormonal estrogens in relatively large doses results in an ‘over-riding’ of corpus luteum function. Our group, using in this fashion moderate doses of hormonal estrogens in women with normal ovarian function, observed no depressing effects upon corpus luteum function (1). Since the non-hormonal estrogen, diethylstilbestrol, is available at low cost, its clinical use has been widespread. Unfortunately many of its applications have been and continue to be uncritical. In view of these facts it seemed worth while to investigate the effects of the contra-physiologic use of moderately small doses of diethylstilbestrol in women with normal ovarian function. The present communication deals with this investigation. Thirteen patients in whom episodes of bleeding occurred from a progestational endometrium were chosen for these studies. Their ages ranged from 18 to 32 years and averaged 25.5 years. Diethylstilbestrol was administered orally in d...
Phosphorylatable serine residues are located in a non-helical tailpiece of a catch muscle myosin.

Myosin from a molluscan catch muscle displays unusual properties: when phosphorylated in the rod by an endogenous heavy-chain kinase, myosin solubility is enhanced and the molecule folds (Castellani & Cohen, Proc. natn. Acad. Sci. U.S.A. 84, (1987) 4058-62). We have now localized the sites of phosphorylation to the carboxy-terminal end of the rod by selective proteolytic cleavage. Two major stretches of sequence, 18 and 21 residues long, have been identified, each containing a single residue of phosphoserine. Analysis of the amino-acid sequence of these two peptides indicates that they form a non-helical tailpiece. We discuss how phosphorylation of this tailpiece might influence enzymatic activity in catch muscle thick filaments.
Radiation dose reduction using a CdZnTe-based computed tomography system: Comparison to flat-panel detectors

Purpose: Although x-ray projection mammography has been very effective in early detection of breast cancer, its utility is reduced in the detection of small lesions that are occult or in dense breasts. One drawback is that the inherent superposition of parenchymal structures makes visualization of small lesions difficult. Breast computed tomography using flat-panel detectors has been developed to address this limitation by producing three-dimensional data while at the same time providing more comfort to the patients by eliminating breast compression. Flat panels are charge integrating detectors and therefore lack energy resolution capability. Recent advances in solid state semiconductor x-ray detector materials and associated electronics allow the investigation of x-ray imaging systems that use a photon counting and energy discriminating detector, which is the subject of this article. Methods: A small field-of-view computed tomography (CT) system that uses CdZnTe (CZT) photon counting detector was compared to one that uses a flat-panel detector for different imaging tasks in breast imaging. The benefits afforded by the CZT detector in the energy weighting modes were investigated. Two types of energy weighting methods were studied: Projection based and image based. Simulation and phantom studies were performed with a 2.5 cm polymethyl methacrylate (PMMA) cylinder filledmore » with iodine and calcium contrast objects. Simulation was also performed on a 10 cm breast specimen. Results: The contrast-to-noise ratio improvements as compared to flat-panel detectors were 1.30 and 1.28 (projection based) and 1.35 and 1.25 (image based) for iodine over PMMA and hydroxylapatite over PMMA, respectively. Corresponding simulation values were 1.81 and 1.48 (projection based) and 1.85 and 1.48 (image based). Dose reductions using the CZT detector were 52.05% and 49.45% for iodine and hydroxyapatite imaging, respectively. Image-based weighting was also found to have the least beam hardening effect. Conclusions: The results showed that a CT system using an energy resolving detector reduces the dose to the patient while maintaining image quality for various breast imaging tasks.« less
Critical IS Issues in the Network Era

A survey of IS academics and practitioners was conducted to identify key IS issues. The list of key IS issues used in the survey includes five new issues that were not present in previous surveys. These issues are Software Reengineering and Maintenance, Client/Server Computing, IS Education and Training, the Internet, and IS Ethics and Legal Issues. Due to the transition of IT platforms from mainframes and microcomputers to network computing, telecommunications and network-related issues are ranked high in the survey. The long-term trends in the ranking of issues over prior surveys indicate that the percentage of technical issues in the top ten is rising while the percentage of managerial issues is declining. A comparison of practitioner and academic rankings of IS issues reveals that academics rank managerial and emerging issues higher than practitioners.
Assessing the effects of nondifferential misclassification of exposures in occupational studies

Abstract Misclassification of historically reconstructed exposures is a common occurrence in occupational epidemiology studies, especially in situations where exposure ratings form the basis of assessment. It is well recognized that nondifferential misclassification of exposure, which is generally the most reasonably assumed form of misclassification in epidemiologic research, will bias effect estimates toward the null value. Moreover, observed exposure-response gradients will be attenuated when exposure misclassification occurs. This paper reviews some indirect methods for examining the possible extent of bias in effect estimates that can result from nondifferential misclassification of exposure. In addition, misclassification of a confounder is considered, where the confounder may be another occupational exposure that is highly correlated with the main exposure under study. Equations are presented to make adjustments of observed cohort data, cases, and person-years to explore the magnitude of distortion...