cssi/SciSciGPT-SciSciNet huggingface dataset:
Life-Long Learning Opportunities for Seniors on the Web

Web-based distance learning programs offer seniors unprecedented access to courses ranging from photography to business accounting. As courses and programs continue to multiply, new and exciting learning opportunities that are both flexible and high quality will be available to millions online. Web based learning will continue to transform education and provide access to important educational resources.
17-Hydroxyprogesterone Responses to Adrenocorticotropin in Children with Premature Adrenarche*

The adrenal secretory response to an iv bolus dose of ACTH was measured in 10 girls (4-8 yr of age), 5 boys (4-9 yr) with premature adrenarche (PA), and 20 normal children. The evening before the ACTH test, each subject took dexamethasone (1 mg at bedtime) to suppress the early morning surge of ACTH. The next morning, 2 serum samples were obtained before the administration of ACTH (Cortrosyn; 0.25 mg), and 2 samples were collected 30 and 45 min after ACTH administration. All samples were assayed for cortisol, dehydroepiandrosterone (DHEA), DHEA sulfate, 17-hydroxyprogesterone (17-OHP), and androstenedione. There was no significant difference in the dexamethasone-suppressed steroid levels between the children with PA and the normal children. After ACTH injection, cortisol, DHEA, 17-OHP, and androstenedione increased significantly. There was no significant change in DHEA sulfate. The mean 17-OHP response to ACTH in girls with PA was significantly higher than that in girls and women whose pubertal development was normal. This response was similar in magnitude to that in a group (n = 5) of obligate heterozygotes for congenital adrenal hyperplasia (CAH). These data suggest that many girls with PA have a mild adrenal steroid secretory defect that resembles the response in adult obligate heterozygotes for CAH due to 21-hydroxylase deficiency. In contrast to the girls, none of the boys with PA had an exaggerated 17-OHP response to ACTH. Thus, these boys had no evidence for an adrenal steroid secretory defect. In summary, although the clinical presentation of boys with PA is similar to that of girls with PA, there is a significant difference in the adrenal steroid secretory response to ACTH. Thus, the biochemical events that cause PA in boys may be different from the corresponding events in girls.
Temperature Regulation in Anorexia Nervosa Patients during Prolonged Exercise

ABSTRACT. The thermal responses to prolonged exercise on a stationary bicycle ergometer have been studied in 10 anorexia nervosa (AN) patients and 5 normal subjects. The patients were young (12–18 years) females (except for 1 case) and had less than 10% of their body weight as fat. The basic experiments were conducted in a moderate environment (24°C) at approximately 65% maximal aerobic power output on all patients and controls. In addition, 2 patients were studied in warm (32°C) conditions, 1 patient in cool (12°C) conditions and 2 patients after being heated for 30 min in a sauna at a temperature of approximately 50°C. Measurements included oxygen uptake, metabolic (M) and total heat production, evaporative sweat loss (E), rectal (Tre) and mean skin temperatures. The results showed that Tre (for a given M) was higher and E lower in the patients than the controls. Passively heating the anorexia patients before exercise increased resting Tre and E but did not affect the “plateau” value of Tre obtained at the end of work. In the warm environment, Tre rose to the same level as observed at 24°C but did not rise above the resting value in cool conditions. Thus it would appear that although patients with AN can regulate their body temperature adequately in a moderate environment, loss of body fat which reduces thermal insulation may decrease the range of ambient temperatures over which Tre can be maintained during exercise. Our data do not support the theory of a loss of central (hypothalamic) thermoregulatory control in anorexia.
Post-traumatic accelerated cohesion: Its recognition and management in group treatment of Vietnam veterans

Post-traumatic accelerated cohesion (p-TAC) is the name given to a frequently observed group phenomenon in the treatment of Vietnam veterans who suffer traumatic war neuroses. It is critical that this group dynamic be discussed, especially since group is widely regarded as the modality of choice in treating these veterans. Post-traumatic accelerated cohesion is the rapid, premature development of cohesion in a group of virtual strangers, and is here presented in terms of its harmful impact on the group and the impasses it creates. Suggestions are given to resolve p-TAC and move the group toward fulfilling its goals. Placed within the self psychology and object relations theoretical frameworks, the discussion addresses issues pertaining to developmental arrests and post-traumatic self disorders and their relationship to p-TAC dynamics.
Serum thyrotropin concentrations are more highly correlated with serum triiodothyronine concentrations than with serum thyroxine concentrations in thyroid hormone-infused thyroidectomized rats.

To assess the relative role of circulating T4 and T3 in the regulation of serum TSH, we have measured serum T4, T3, and TSH concentrations in normal and thyroidectomized rats, some of which were chronically infused with T3 or T4. Serum T3) T4, and TSH concentrations were measured 7 and 14 days after surgery. Some groups of infused rats were mildly hypothyroid, as judged by elevated serum TSH concentrations. At both 7 and 14 days, there was a significant inverse correlation between serum T3 and serum TSH concentrations (day 7, r = 0.65, P < 0.01; day 14, r = 0.71, P < 0.01). The coefficients for the inverse correlations between serum T4 and TSH concentrations were 0.37 on day 7 (P < 0.05) and 0.37 (P < 0.05) on day 14. Linear regression analysis was performed using TSH as the dependent variable for outcome and serum T3 and T4 concentrations as the independent predictor variables. This analysis revealed that after controlling for T3, TSH and T4 were no longer significantly correlated (P = 0.14). The correla...
An Analysis of the Magnetic Second-Subharmonic Oscillator

An analysis is given for the second-subharmonic parametric oscillator with two ferromagnetic cores. "Square-loop" reasoning is employed with extreme idealization of the magnetic core properties; the effects of hysteresis losses and saturated inductance are subsequently considered. The steady-state operation, both with voltage and with current pump drives, is studied to determine the values of the circuit parameters for which the subharmonic oscillations occur. The transient build-up is evaluated by means of difference equations, and the influence of the magnitude of the excitation signal upon the transient is illustrated. The experimental waveforms agree with the analytical predictions for a wide range of drive frequencies, the upper limit investigated being 3 Mc.
Response of Lingual Ascorbic Acid Test and Salivary Ascorbate Levels to Changes in Ascorbic Acid Intake

This study sought to determine whether the lingual ascorbic acid test (LAAT) and measurement of salivary ascorbate refXect plasma and leukocyte ascorbate levels during controlled periods of ascorbic acid depletion and supplementation.Eleven healthy non-smoking men, aged 19-28 years, ate a diet that was repeated every seven days and was adequate in all nutrients except ascorbic acid (AA). This basal diet, which provided less than 5 mg of AA per day, was supplemented with 60 mg of AA per day for two weeks, 0 mg (placebo) per day for four weeks, 600 mg per day for three weeks, and 0 mg per day for four weeks. Oral examinations, the lingual ascorbic acid test, and measurement of salivary, plasma, and leukocyte ascorbate concentrations were conducted throughout the study.Ascorbic acid concentrations in plasma and leukocytes responded rapidly to changes in vitamin C intake. LAAT-derived ascorbate values were unrelated to ascorbic acid intake and plasma and leukocyte ascorbate concentrations. Salivary ascorbate ...
The role of colostomy in the management of anorectal malformations

The role of the colostomy in the definitive correction of anorectal malformations is controversial with regard no only to indications for its use, but also to location and type. We reviewed the records of 272 patients with 307 colostomies and analyzed the frequency of complications related to these controversial points. There were 250 completely divided and 57 loop colostomies, constructed in either the sigmoid or transverse colon. Twenty-five colostomies were associated with complications that included retraction, stenosis, dehiscence, prolapse, infection, bowel obstruction, sepsis, and death. Twelve additional colostomies were placed in positions that impeded the definitive correction of the malformation: 9 sigmoidostomies were too distal and 3 were located in the right-upper abdominal quadrant and did not permit pull-through without tension. Colostomy prolapse and pull-through infection were statistically less likely with a completely diverting colostomy. Thirty-five patients with rectovestibular malformations were encountered in this series. Ten were referred from other institutions after attempted repair without a colostomy and all 10 had complications of infection, dehiscence, retraction, and reopening of the fistula. In contrast, there were no complications in the remaining 25, in whom the repair was preceded by a colostomy, nor after re-repair of the other 10. These findings support the need for a colostomy prior to the repair of this malformation. We recommend a carefully constructed, high, completely diverting sigmoid colostomy prior to the initial definitive repair of anorectal malformations. A right transverse colostomy is preferable preceding redo operations.
The stability of parenting behaviors over the first 6 years of life

The purpose of this investigation was to examine the relative and absolute stability of parenting behaviors over the first 6 years of children's lives. In 1991, a diverse sample of 1364 participants was enrolled in the Study of Early Child Care at 10 sites across the United States. Parenting behaviors were rated annually over a 6-year period using lab observations and home visits. Eight hundred and ninety-three participants had complete data from each time point to test the hypotheses of interest. The data show that both sensitive and stimulating parenting behaviors display considerable relative and mean level stability over the first 6 years of life, whereas negative aspects of parenting, like detachment and negative regard, do not. Implications for research and interventions are discussed.
The two-minute teacher.

Radiology educators frequently find themselves working next to medical students at a view station or in a procedure room. Often the clinical workload is substantial, and relatively little time is available for direct student teaching. In such a context, much of the student’s learning is largely observational, listening as radiologists dictate cases and interact with residents, fellows, and referring physicians. Yet it is important that students benefit from the attention of radiology educators. If not, they may leave the radiology department having learned little and even feeling that they have been largely ignored. How can radiology educators ensure meaningful educational interactions during the clinical workday without setting aside large chunks of time specifically for teaching? One way is to arrive every day with a set of strategies and techniq ues that make meaningful educational interactions possible in even very short periods. We have developed such a set of approaches, each of which generally requires only a few minutes. At the beginning of the day, between cases, as interruptions in workflow occur, and at the end of the day, the 2-minute educator can draw as appropriate from this set of options to promote learner-educator interaction and foster enhanced learning. This may happen only once or multiple times per day, but each time it does so, it helps to make the most of what otherwise might be a missed educational opportunity. Having such a standard set of approaches can lower the ‘‘energyof activation’’ofteaching.If aneducatorhasnostanding set of strategies and techniques to drawon, other demands on time and attention can make it difficult to devise new teaching opportunities on the spot. With this approach, however, the educator has a preexisting menu from which to choose, based on the particular circumstances at hand. Moreover, each approach can be adapted and customized as appropriate to meet the needs of individual learners. These are starting points for an educational encounter, not rigid formulas. Finally, this approach can be employed not just by faculty members but by residents, fellows, technologists, and other radiology educators. Here are seven such strategies.
COSMOLOGY AS A SCIENCE.

In recent years observational techniques at cosmological distances have been improved so that cosmology has become an empirical science, rather than a field for unchecked speculation. There remains the fact that its object, the whole universe, exists only once; hence we are unable to separate ‘general’ features from particular aspects of ‘our’ universe. This might not be a serious drawback if we were justified in the belief that presently accepted laws of nature remain valid on the cosmological scale. In the author’s opinion, however, there are grounds for doubting that belief. The three arguments presented are (1) the possibility that apparent constants of nature may during cosmological times turn out to vary (Dirac); (2) the effective break-down of the principle of relativity caused by the effects of the cosmological environment on local experiments; and (3) the fact that present theory leads to field singularities at the early stages of the expanding universe, which might be a signal that currently accepted theoretical concepts are inadequate for an understanding of highly condensed matter.
Team reward attitude: construct development and initial validation

This paper reports the development of a team reward attitude construct and intial validation of a measure in a longitudinal study of team members (initial n = 566). Confirmatory factor analysis results provide support for a revised 9-item scale in two different time periods separated by four months. The measure was positively related to other team-related attitudes (preference for group work and perceived efficacy of teams) and locus of control, and negatively related to a proxy for ability. Implications of the research and future research directions are addressed. Copyright © 2001 John Wiley & Sons, Ltd.
Convergence of the majorization method for multidimensional scaling

In this paper we study the convergence properties of an important class of multidimensional scaling algorithms. We unify and extend earlier qualitative results on convergence, which tell us when the algorithms are convergent. In order to prove global convergence results we use the majorization method. We also derive, for the first time, some quantitative convergence theorems, which give information about the speed of convergence. It turns out that in almost all cases convergence is linear, with a convergence rate close to unity. This has the practical consequence that convergence will usually be very slow, and this makes techniques to speed up convergence very important. It is pointed out that step-size techniques will generally not succeed in producing marked improvements in this respect.
The relational correspondence between category exemplars and names

While recognizing the theoretical importance of context, current research has treated naming as though semantic meaning were invariant and the same mapping of category exemplars and names should exist across experimental contexts. An assumed symmetry or bidirectionality in naming behavior has been implicit in the interchangeable use of tasks that ask subjects to match names to stimuli and tasks that ask subjects to match stimuli to names. Examples from the literature are discussed together with several studies of color naming and basic emotion naming in which no such symmetry was found. A more complete model of naming is proposed to account for flexible mapping of names to items. Principles of naming are suggested to describe effects of stimulus sampling, differing access to terms, task demands, and other impacts on naming behavior.
Spatio-temporal association rule mining framework for real-time sensor network applications

In this paper, we present a data mining framework to estimate missing or corrupted data in sensor network applications - a frequently occurring phenomenon in this domain. The framework is naturally germane to the spatio-temporal analysis of relational data stream evolution. Our method utilizes association rules to capture spatio-temporal correlations in multivariate, dynamically evolving, and unbounded sensor data streams. Existing approaches that tackled this problem do not account for the multi-dimensionality of the node data and their relationship; furthermore they entail simplistic and/or premature assumptions on the temporal and spatial factors to overcome the complexity of the streaming environment. Our technique, called Mining Autonomously Spatio-Temporal Environmental Rules (MASTER), comprehensively formulates the problem of mining patterns in sensor data streams, and yet remains provably adaptive to bounded time and space costs while probabilistically assuring a bounded estimation error. Simulation experiments show MASTER's efficiency in terms of overhead as well as the quality of estimation.
The effect of wavelength on visual perceptual latency

Abstract The image of a slit of light whose bottom (standard) half was held constant in wavelength and intensity was swept across the stationary retina. Each of three Ss aligned the leading edge of the top (comparison) half of the slit, whose wavelength was systematically varied by E, with the leading edge of the standard by adjusting the intensity of the comparison. It was reasoned that if visual perceptual latency is independent of wavelength, then the alignment function which relates wavelength of comparison to relative energy of comparison required for apparent alignment with the standard should be identical in shape to luminosity functions obtained from the same Ss. The mean alignment function was not significantly different from the mean luminosity functions as determined by the threshold and direct matching techniques, and it was concluded that wavelength does not influence visual perceptual latency.
Low-molecular-weight heparins: pharmacologic profile and product differentiation

The interchangeability of low-molecular-weight heparins (LMWHs) has been the subject of discussion since these products were first introduced for the prophylaxis of deep vein thrombosis. Experimental evidence now exists to show that LMWHs differ from each other in a number of characteristics. Products have been differentiated on the basis of molecular weight and biologic properties, but only limited information derived from the clinical setting is available. Potency has been described on the basis of anti-Factor Xa activity, but at equivalent anti-Xa activities, the anti-Factor IIa activity of different products shows marked variations. At the relatively small doses used for the management of postsurgical deep vein thrombosis, the effect of these interproduct differences may be relatively minor, but as LMWHs are developed for therapeutic use at much higher doses, such differences may become clinically important. Variations in safety and efficacy reported in clinical trials of LMWHs may reflect the known differences in their molecular composition and pharmacologic properties.
Nanotechnology advances and applications in information storage

A brief review of some applications of nanotechnology to information storage is given with the focus on self-assembled nanoporous alumina templates for patterned media.Ordered nanoporous alumina templates were fabricated by self-assembly technology. A two-step anodization process was also carried out to obtain templates with pores perpendicular to the substrate without removing the aluminum and barrier layer. Polycrystalline structure was observed with a grain size of about 2 μm in which the pores were almost perfect hexagonally ordered. The pore arrays exhibit different orientation along the boundaries of neighboring grains. Nanopatterning implemented by electron-beam lithography demonstrates the ability to write pores forming concentric circles with pore diameter as small as 50 nm.
Faculty member feedback reports

Summary Background Obtaining sufficient written feedback from faculty members on clerkship student evaluations is challenging. Few successful interventions, however, have been published on improving written feedback or evaluation content. Methods We evaluated and scored medicine clerkship student evaluation forms from one academic year (2011/12) for timeliness, grade distribution and the number of written comments. Based on this assessment, faculty members received a feedback report documenting their performance at the end of the year to encourage improvement. Medicine clerkship student evaluation forms were scored again for the same criteria the following academic year (2012/13) to ascertain the impact of the feedback reports on evaluation timeliness, grade distribution and the number of written comments. Results Sixty-one faculty members completed student clerkship evaluations in both years, and received feedback reports. There was no change in the overall timeliness, grade distribution or number of written comments. There were 13 faculty members (21%) identified as ‘low performing’, who were responsible for 75 per cent (21/28) of the evaluation forms without any written comments. Within this subgroup, the proportion of evaluation forms with comprehensive comments (mostly sentences) increased after implementing the feedback reports [3/42 (7%) versus 9/25 (36%), p = 0.006]. Obtaining sufficient written feedback from faculty members on clerkship student evaluations is challenging Discussion At our institution, the majority of inadequately completed clerkship evaluation forms are generated by a small group of low-performing faculty members. Providing feedback to these faculty members about their student evaluations was associated with improved performance the next year. Targeted feedback to low-performing faculty members may be an effective strategy to improve student evaluations.
Chatham fault: A reinterpretation of the contact relationships between the Giddings Brook and Chatham slices of the Taconic allochthon in New York

The Chatham fault separates the structurally lowest Giddings Brook slice of the Taconic allochthon from the next higher Chatham slice in New York. Slivers of the autochthonous shelf sequence within the Chatham fault zone were attributed by Zen (1967) to a tectonic melange that separated two structurally independent slide masses in Middle Ordovician time. The zone of inclusions and the fault thus represented a primary boundary between two allochthonous paleotectonic units. Restudy of the Chatham fault shows that it is a major postmetamorphic thrust fault that clearly postdates emplacement of the allochthonous rocks assigned to the Giddings Brook and Chatham slices. A sliver of Grenville basement gneiss with attached miogeoclinal shelf-sequence rocks and other slivers suggests dip-slip movement in excess of 3.5 kin on the east-dipping fault. Geometric relationships and textural evidence indicate that the tectonic melange in the (Chatham fault zone postdates Taconic dynamo-thermal metamorphism and further suggest that the Giddings Brook and Chatham slices may have been continuous before Acadian? imbrication. The western contact of the Rensselaer Plateau slice with the Giddings Brook slice may also be a zone of late imbrication rather than a primary Taconian contact.
Tropical Squall Lines of the Arizona Monsoon

Three cases of squall lines composed of strong to severe thunderstorms that formed over Arizona, and Sonora (Mexico) on July, 16-17 and 17-18, 1984, and August 2-3, 1986, are examined. Data, which included satellite imagery, VISSR-derived fields, surface data, and records or cloud-to-ground lightning strikes, indicate that the initiation, growth, and dissipation of all three squall lines were very similar. Results indicate that these mesoscale convective systems developed in an environment of relatively strong low-level shear with very weak shear aloft and that they possessed almost all the properties of a typical tropical squall line.
The relationship of the apical foramen to the anatomic apex of the tooth root

Abstract Eight hundred and seventy-seven teeth were examined to determine the frequency, direction, and distance of deviation of the major formen from the anatomic root apex. The frequency of deviation averaged 92.4 per cent, depending on the class of tooth examined. The predominating direction of deviation was dependent on the class of tooth examined. The average distance between the anatomic apex and the major foramen opening in those teeth presenting a deviation averaged approximately 0.59 mm.
Plagiarism: it's not just for students

This paper examines the issue of plagiarism at a professional level, using an ethics lens. It includes information about the general situation, cases in engineering and technology, and suggestions for journal editors and reviewers to help stem the tide of an ethical problem that is on the rise.
CBCV: a CAD-based computer vision system

The CBCV system has been developed in order to provide the capability of automatically synthesizing executable vision modules for various functions like object recognition, pose determination, quality inspection, etc. A wide range of tools exist for both 2D and 3D vision, including not only software capabilities for various vision algorithms, but also a high-level frame-based system for describing knowledge about applications and the techniques for solving particular problems. >
Skew Disperson and Continuity of Local Time

Results are provided that highlight the effect of interfacial discontinuities in the diffusion coefficient on the behavior of certain basic functionals of the diffusion, such as local times and occupation times, extending previous results in (Appuhamillage et al., Ann Appl Probab 21:183–214, 2011; Water Resour Res 46:W07511, 2009) on the behavior of first passage times. The main goal is to obtain a characterization of large scale parameters and behavior by an analysis at the fine scale of stochastic particle motions. In particular, considering particle concentration modeled by a diffusion equation with piecewise constant diffusion coefficient, it is shown that the continuity of a natural modification of local time is the individual (stochastic) particle scale equivalent to continuity of flux at the scale of the (macroscopic) particle concentrations. Consequences of this involve the determination of a skewness transmission probability in the presence of an interface, as well as corollaries concerning interfacial effects on occupation time of the associated stochastic particles.
Bureaucratic discretion and alternative teacher certification: understanding program variation in Missouri.

Alternative teacher certification literature has contributed significantly to our understanding of this approach to teacher preparation. However, this literature has more often than not treated alternative teacher certification programs (ATCPs) as a black box, thus ignoring program heterogeneity. The present study examines how and why five ATCPs in Missouri have evolved in different ways. To understand this variation and its potential significance for researchers and practitioners, we use political science literature on bureaucratic discretion to understand programs’ varied responses within the same state policy context. Using a multiple case study design, we present two key findings. First, external factors such as the state’s regulatory approach, programs’ relationships with school districts, and programs’ relationship with external partners shape program coordinators’ perceptions of their discretionary authority. Second, within an environment of limited regulation, programs responded to these external factors in ways that shaped programs in
The Perils and Promises of International Surveys of School Achievement: A Response to Howard Russell’s “Connections among Factors in Education”

tional research community well, has again made a valuable contribution to the discourse by sharing some of his observations on the perils, as well as some of the promise, of surveying school achievement around the world. In the incubative stages of the Second International Mathematics Study (SIMS) in the mid 1970s, Howard Russell made it clear that an emphasis on analyzing student performance at the item level should be an essential component of such a project. Concurrently, James Wilson, University of Georgia, had written a paper commissioned by the U.S. National Institute of Education (unpublished, 1975) on the topic, "If There Is to Be a Second IEA Study of Mathematics, What Should It Be Like?" A major thesis of the Wilson paper, whose recommendations went far in providing the conceptual basis for SIMS, was that a major thrust of such a study should be curricular, and that in order to be of maximal value to curriculum and instructional specialists, the study must be "fine-grained," offering detailed data at the item level, with relatively little attention and/or importance ascribed to subscores (and no interest accorded a total test score). To be sure, for a topic like geometry, where the curricular content and, hence, the match with the test items, varies wildly from country to country (see Travers & Westbury, 1989), constructing a valid, informative subscore is extremely problematic.
New cell cycle compartments identified by multiparameter flow cytometry

Simultaneous measurements of cellular DNA and RNA as well as estimates of the sensitivity of DNA in situ to denaturation by acid (which correlates with the degree of chromatin condensation) and cell ability to incorporate 5-bromodeoxyuridine (BUdR), performed on over 40 different cell systems enabled us to subclassify cells into 12 functionally distinct cell cycle compartments. Quiescent cells had low RNA values, DNA very sensitive to denaturation, and they did not incorporate BUdR. Although in most cell systems they had 2C DNA content (G1Q), quiescent cells with higher DNA values (SQ and G2Q) were also seen. The G1 phase of exponentially growing cells had two distinct compartments, A and B. G1 cells entered S phase only from the B compartment. An increase in RNA and a decrease in the sensitivity of DNA to acid denaturation beyond a specific level characterized the transition of cells from the A to B compartments. Since the G1A to G1B transition was not linear but exponential, it may be assumed that a non-deterministic event triggering cell progression into the cycle resides within G1A. Under adverse growth conditions the probability of a G1A to G1B transition decreased. Cells In G2 had DNA more sensitive to acid denaturation than S or G1 phase cells. Mitotic cells had the most condensed chromatin and their RNA content was twice that of G1A cells. Differentiated cells were characterized by 2C DNA (G1D) but, depending on the cell type, had varying RNA content and different degrees of chromatin condensation. A hitherto undescribed category of cells undergoing transition from quiescence to the cycle (or vice versa) was distinguished based on their intermediate values of RNA, sensitivity of DNA to acid denaturation and inability to incorporate BUdR at the rate characteristic for S cells. Depending on their DNA content (C) at the time of transition these cells could be classified as G1T (2C), ST (4>C>2) or G2T (4C).
Biomarkers as Early Predictors of Long-Term Health Status and Human Immune Function

A central issue that must be addressed by phytonutrient research is how to assess the effects of phytonutrients on long-term health. Proper assessment of these effects requires the measurement of biomarkers of long-term health in people consuming any particular phytonutrient. This is a brief review of what is known about biomarkers of cancer risk, immune function, and aging. Relatively few biomarkers of long-term health have been even partially validated in experimental animals or people.
Reactions with dye free radicals reveal weak redox properties of drugs.

Abstract The calcium release channel (CRC) of the skeletal sarcoplasmic reticulum is rich in thiol groups and is strongly regulated by covalent modification of these thiols. Oxidizing reagents activate the release channel, whereas reducing reagents inhibit the channel. However, most CRC regulators are not thiol reagents. Here, we propose that reversible redox interactions are involved in regulation of the CRC by nonthiol reagents. This hypothesis was tested with several CRC regulators. The local anesthetics tetracaine, procaine and QX-314, which block the CRC, behaved as electron donors in reactions with dye free radicals. In contrast, ryanodine, caffeine, doxorubicin and daunorubicin, compounds known to activate the release channel, all accepted electrons from dye anion radicals. Moreover, release of Ca2+ from SR initiated by doxorubicin (acceptor) was antagonized by local anesthetics (donors). Based on the redox characterization of CRC modulators, we propose a functional model in which channel inhibitor...
Assessment of the efficacy and safety of antiarrhythmic therapy for chronic atrial fibrillation: Observations on the role of trial design and implications of drug-related mortality

Abstract The findings in clinical trials of antiarrhythmic drug efficacy and safety are frequently difficult to compare, since study design often has an important effect on trial outcome. To explore this problem further, we compared three designs—randomized control, nonrandomized control, and uncontrolled—collectively enrolling 2415 patients in 21 trials reporting on the role of quinidine in the prevention of chronic atrial fibrillation. The proportion of patients remaining in sinus rhythm at 3, 6, and 12 months after cardioversion was calculated by means of Kaplan-Meier techniques, and the data were pooled for each trial design. For the randomized control trials the difference in the absolute percentage of patients remaining in sinus rhythm in the quinidine and control groups was 24% at each of the three fellow-up intervals. Contrary to findings in the randomized control trials, the magnitude of the treatment benefit in nonrandomized trials was smaller and declined markedly over time. The percentage of patients remaining in sinus rhythm in the uncontrolled trials was intermediate to the percentages in the other two trial designs. When the data from all three trial designs were pooled, the crude mortality rate was 2.0% in quinidine-treated patients and 0.6% in control patients. Sudden cardiac death or ventricular fibrillation was the cause of death in 13 of 19 patients for whom the cause of death was known, highlighting the potential risk of quinidine-induced proarrhythmia. Although quinidine is effective in maintaining sinus rhythm, estimates of the treatment effect vary among trial types. Because antiarrhythmic therapy with quinidine for suppression of atrial fibrillation has not been shown to reduce the risk of mortality, the decision to institute therapy should be guided strongly by patient symptoms.
An outbreak of hepatitis A among health care workers: risk factors for transmission.

OBJECTIVES. The purpose of this study was to investigate a nosocomial outbreak of hepatitis A that occurred in the burn treatment center of a referral hospital. METHODS. Retrospective cohort and case-control studies were performed to determine acquisition rates and risk factors for transmission. Adjusted infection rates were calculated by week of exposure. A case-control study was conducted to determine potential mechanisms for nosocomial acquisition. Recently infected health care workers were defined as case patients; exposed, serosusceptible health care workers without infection served as controls. RESULTS. The outbreak of hepatitis A affected 11 health care workers and 1 other burn patient (1 secondary patient case). All 11 health care workers became ill after the admission of a man and his 8-month-old son who developed hepatitis A while in the hospital. The cumulative incidence risk ratio was elevated for health care workers caring for either the infant or the father during the same week of exposure. ...
Rank-based spatial clustering: an algorithm for rapid outbreak detection

Objective Public health surveillance requires outbreak detection algorithms with computational efficiency sufficient to handle the increasing volume of disease surveillance data. In response to this need, the authors propose a spatial clustering algorithm, rank-based spatial clustering (RSC), that detects rapidly infectious but non-contagious disease outbreaks. Design The authors compared the outbreak-detection performance of RSC with that of three well established algorithms—the wavelet anomaly detector (WAD), the spatial scan statistic (KSS), and the Bayesian spatial scan statistic (BSS)—using real disease surveillance data on to which they superimposed simulated disease outbreaks. Measurements The following outbreak-detection performance metrics were measured: receiver operating characteristic curve, activity monitoring operating curve curve, cluster positive predictive value, cluster sensitivity, and algorithm run time. Results RSC was computationally efficient. It outperformed the other two spatial algorithms in terms of detection timeliness, and outbreak localization. RSC also had overall better timeliness than the time-series algorithm WAD at low false alarm rates. Conclusion RSC is an ideal algorithm for analyzing large datasets when the application of other spatial algorithms is not practical. It also allows timely investigation for public health practitioners by providing early detection and well-localized outbreak clusters.
Calculation of transmission losses from a planning viewpoint

An analytical technique based on statistical methods is developed to evaluate the expected difference in the transmission losses, in a defined study area, between two overall systems that use two different 500 kV line configurations that are technically and environmentally acceptable. A study area is carefully chosen so that essentially all the difference in IR loss between any two alternatives occurs in that study area. The annual load duration curve of the entire system is used to define the annual generation schedule pattern of the study area. AC load flows are performed on a reduced system that has all of the study area represented. Using power conservation equation and Maclaurin series, the interface flow is eliminated from the study area loss function. The load-duration curve, which is a reliability function, is expressed as a continuous function of the study area load demand. This function is used to derive the probability density function of the study area load demand. The annual expected value of the difference in the study area losses between two alternatives is evaluated using the above probability density function and the derived loss function. Calculated values show very good agreement with those obtained with load flow studies. >
Characterization of a membrane-based gradient generator for use in cell-signaling studies{

This paper describes a method to create stable chemical gradients without requiring fluid flow. The absence of fluid flow makes this device amenable to cell signaling applications where soluble factors can impact cell behavior. This device consists of a membrane-covered source region and a large volume sink region connected by a microfluidic channel. The high fluidic resistance of the membrane limits fluid flow caused by pressure differences in the system, but allows diffusive transport of a chemical species through the membrane and into the channel. The large volume sink region at the end of the microfluidic channel helps to maintain spatial and temporal stability of the gradient. The chemical gradient in a 0.5 mm region near the sink region experiences a maximum of 10 percent change between the 6 and 24 h data points. We present the theory, design, and characterization of this device and provide an example of neutrophil chemotaxis as proof of concept for future quantitative cell-signaling applications.
Aligning Class Hierarchies with Grass-Roots Class Alignment

The performance of an ontology alignment technique largely depends on the amount of information that can be leveraged for the alignment task. On the semantic Web, end-users may explicitly or implicitly generate ontology alignments during their use of the semantic data. This kind of end-user-generated ontology alignment, which we call grass-roots ontology alignment, is an important source of information that is yet to be taken into account by current ontology alignment techniques. Grass-roots ontology alignment, often generated as a side effect of other data manipulations, could be user-specific, task-specific, approximate, or even contradictory. This paper reports our work on reusing grass-roots class alignment for aligning class hierarchies. A grass-roots class alignment, though approximate, still reveals some facts about relationships between different classes. We formalize facts about class relationships that can be inferred from an alignment under different cases. We then apply forward-chaining inference to the facts knowledge base to infer more facts. The facts KB is then leveraged for ontology alignment purposes. To deal with uncertainty and inconsistency, each fact is associated with an evidence that tells how the fact is obtained. The evidences are used to select better-supported facts in case of inconsistency.
Review of Relevant Literature

Beginning with this issue of the Journal, we will hereafter publish editorialized abstracts of current surgical and oncologic literature that we think should be of interest to our readers. There is a great gap in understanding between various specialties. This is in part due to the vast amount of literature that tends to sequestration within each specialty and that each specialist tends to limit himself to. These abstracts, we hope, will help to bridge this gap in understanding and appreciation, and will contribute to the ultimate concern of all of us, which is better care of patients.
Reliability of neurological soft signs in children: reevaluation of the PANESS.

Testretest reliability and intellectualbehavioral correlates of a revised version of the Physical and Neurological Examination for Soft Signs (PANESS) were evaluated. The WISC-R and PANESS were administered to a heterogeneous clinical sample of 28 6-to 8-year-old children. Test-retest interval for PANESS retest was approximately 28 days with 15 children retested by same testers and the remaining children retested by different testers. Results indicated that PANESS total score is a reliable indicator of overall performance; tester assignment and retest had negligible effects on total score. Grade of subcategory scores proved unreliable across examiners but occurrence/nonoccurrence scores were more robust. Performance on the PANESS was significantly correlated with WISCR indices sensitive to brain dysfunction, and behavioral factors implicated in the description of minor neurological dysfunction. Further research evaluating discriminant validity of the examination and changes in performance as a result of development is recommended.
Multicategory Crowdsourcing Accounting for Variable Task Difficulty, Worker Skill, and Worker Intention

Crowdsourcing allows instant recruitment of workers on the web to annotate image, webpage, or document databases. However, worker unreliability prevents taking a worker’s responses at “face value”. Thus, responses from multiple workers are typically aggregated to more reliably infer ground-truth answers. We study two approaches for crowd aggregation on multicategory answer spaces: stochastic modeling-based and deterministic objective function-based. Our stochastic model for answer generation plausibly captures the interplay between worker skills, intentions, and task difficulties and captures a broad range of worker types. Our deterministic objective-based approach aims to maximize the average aggregate confidence of weighted plurality crowd decision making. In both approaches, we explicitly model the skill and intention of individual workers, which is exploited for improved crowd aggregation. Our methods are applicable in both unsupervised and semi-supervised settings, and also when the batch of tasks is heterogeneous , i.e., from multiple domains, with task-dependent answer spaces. As observed experimentally, the proposed methods can defeat “tyranny of the masses”, i.e., they are especially advantageous when there is an (a priori unknown) minority of skilled workers amongst a large crowd of unskilled (and malicious) workers.
Sensitivity of scratch resistance to grinding-induced damage anisotropy in silicon nitride

Single-grit scratch experiments were conducted on polished as well as on longitudinally and transversely ground silicon nitride specimens to investigate the influence of grinding direction on scratch resistance. It was found that the volume of material removed and the extent of cracking were the largest when the scratches were parallel to the grinding direction and were the least on the polished specimens. These results were rationalized based on the grinding-induced sub-surface damage anisotropy and were quantified using a scratch resistance measure. A linear elastic fracture mechanics analysis revealed that only cracks of certain length and orientation grow to cause the observed trends in the scratch resistance.
Defective Transport of the Obesity Mutant PC1/3 N222D Contributes to Loss of Function

Mutations in the PCSK1 gene encoding prohormone convertase 1/3 (PC1/3) are strongly associated with obesity in humans. The PC1/3N222D mutant mouse thus far represents the only mouse model that mimics the PC1/3 obesity phenotype in humans. The present investigation addresses the cell biology of the N222D mutation. Metabolic labeling experiments reveal a clear defect in the kinetics of insulin biosynthesis in islets from PC1/3N222D mutant mice, resulting in an increase in both proinsulin and its processing intermediates, predominantly lacking cleavage at the Arg-Arg site. Although the mutant PC1/3 zymogen is correctly processed to the 87-kDa form, pulse-chase immunoprecipitation experiments, labeling, and immunohistochemical experiments using uncleavable variants all demonstrate that the PC1/3-N222D protein is largely mislocalized compared with similar wild-type (WT) constructs, being predominantly retained in the endoplasmic reticulum. The PC1/3-N222D mutant also undergoes more efficient degradation via the ubiquitin-proteasome system than the WT enzyme. Lastly, the mutant PC1/3-N222D protein coimmunoprecipitates with WT PC1/3 and exerts a modest effect on intracellular retention of the WT enzyme. These profound alterations in the cell biology of PC1/3-N222D are likely to contribute to the defective insulin biosynthetic events observed in the mutant mice and may be relevant to the dramatic contributions of polymorphisms in this gene to human obesity.