cssi/SciSciGPT-SciSciNet huggingface dataset:
Failure to disrupt development of cholinergic fiber patches in the superior colliculus in nitric oxide synthase deficient mice

Abstract Nitric oxide (NO) has been shown to mediate refinement of glutamatergic axonal pathways during development. In this study, we investigated whether the development of a cholinergic pathway in the intermediate gray layer (IGL) of the mouse superior colliculus (SC) is also mediated by NO. The pathway was labeled using an antibody directed against choline acetyltransferase (ChAT) and its distribution examined in normal C57/BL6 mice and in knockout mice in which the genes for the neuronal isoform of nitric oxide synthase (NOS) or both the endothelial and neuronal isoforms of NOS had been disrupted. We also examined the development of expression of NOS using nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) staining. NADPHd labeled cells were found within the IGL by P8 and formed loose clusters of cells by P12–P15. ChAT and NADPHd labeled fibers were first observed at P12 and gradually established their characteristic two-tiered patchy pattern between P14 and P21. Comparison of the ChAT labeled fiber distribution in normal, single nNOS and double e,nNOS knockout mice revealed no differences between these three groups. We therefore conclude that nitric oxide does not mediate refinement of this cholinergic pathway.
Aldrin epoxidase activity and cytochrome P-450 content of microsomes prepared from alfalfa and cabbage looper larvae fed various plant diets

Abstract The alfalfa looper ( Californica autographica ) and the cabbage looper ( Trichoplusia ni ) were reared through the fourth instar on a semidefined artificial diet and for the first 60 hr of the last instar on fresh leaves of one of their host plants. Microsomes prepared from midguts and a carcass segment which included the fat body were then assayed for aldrin epoxidase activity and cytochrome P -450 content. Epoxidation by midgut microsomes of alfalfa loopers fed peppermint leaves was at a rate up to eight times that of larvae fed alfalfa, snap beans, or broccoli. The epoxidase activity of the carcass microsomes was induced about fourfold by the peppermint diet. Midgut microsomes prepared from cabbage looper larvae reared on peppermint leaves were also more active (about four times) than those reared on alfalfa, broccoli, or cabbage. Although the epoxidase activity of the carcass microsomes of the cabbage loopers was low, about one-eighth that of the midgut microsomes, this enzyme was greatly induced by peppermint leaves. In neither species did the peppermint leaf diet cause a corresponding increase in the cytochrome P -450 content of the microsomes, the maximum difference between peppermint and the other plants being about twofold. Bioassays of cabbage looper larvae reared on broccoli or peppermint and of alfalfa loopers reared on alfalfa or peppermint indicated that the stimulation of microsomal oxidase activity by the peppermint constituents provided increased tolerance for carbaryl and methomyl but not acephate.
Spare the (Elastic) Rod

Physicists love emergence. From a welter of complex details about a system's constituents, simple and universal rules sometimes emerge that adequately describe the collective behavior of the components. Even if these rules are not completely universal, they often have only a few relevant parameters, a vast simplification compared to the many that describe the constituents individually. But as Vafabakhsh and Ha remind us on page 1097 of this issue ( 1 ), emergent behavior can conceal important aspects of a system. Using a beautiful application of fluorescence microscopy, the authors provide the clearest evidence to date that the elastic-rod model for DNA mechanics, an emergent description that works well on long length scales, breaks down on shorter length scales relevant to cell biology.
Neurovascular photoacoustic tomography.

Neurovascular coupling refers to the relationship between neuronal activities and downstream hemodynamic responses. Photoacoustic tomography (PAT), enabling comprehensive label-free imaging of hemodynamic activities with highly scalable penetration and spatial resolution, has great potential in the study of neurovascular coupling. In this review, we first introduce the technical basis of hemodynamic PAT—including label-free quantification of total hemoglobin concentration, blood oxygenation, and blood flow—as well as its applications in hemodynamic monitoring. Then, we demonstrate the potential application of PAT in neurovascular imaging by highlighting representative studies on cerebral vascular responses to whisker stimulation and Alzheimer’s disease. Finally, potential research directions and associated technical challenges are discussed.
Angiomatoid melanoma: a novel pattern of differentiation in invasive periocular desmoplastic malignant melanoma.

A case of locally invasive, long-standing desmoplastic and amelanotic malignant melanoma is described in an 84-year-old man. Histologic examination of the involved periorbital tissue showed neoplastic foci exhibiting a novel pattern reminiscent of microvascular proliferation. These regions were characterized by malignant, S-100-positive tumor cells lining vessel-like spaces in transverse sections and forming tubuler-like structures in longitudinal sections. Recent data indicate that melanoma cells may express genes and patterns of differentiation in vitro akin to endothelial cells. Because angiosarcoma often involves facial and scalp skin of elderly individuals, awareness of angiomatoid differentiation in melanoma has important diagnostic implications. HUM PATHOL 31:1520-1522.
IL-21 and BAFF/BLyS synergize in stimulating plasma cell differentiation from human marginal zone B cells as well as from circulating peripheral blood B cells from autoimmune patients

IL-21 promotes plasma cell (PC) differentiation while BAFF promotes B-cell survival. Here, we report that IL-21 synergizes with BAFF to elicit BLIMP-1 induction, PC differentiation and IgG production from a novel population of human splenic memory B cells. These human marginal zone analogue B cells are exquisitely sensitive to IL-21 and BAFF in the absence of further co-stimulation. The ability of IgG+ marginal zone analogue to respond specifically and exclusively to IL-21 and BAFF demonstrates that they are uniquely poised to respond to antigen-independent signals and differentiate into IgG-producing PC, thereby replenishing serologic memory. Importantly, peripheral blood B cells from a portion of patients with systemic lupus erythematosus and rheumatoid arthritis were highly responsive to stimulation with IL-21 and BAFF. These data suggest that IL-21 and BAFF may be capable of inducing PC differentiation from memory B cells with autoreactive specificities and thereby contribute to autoimmunity.
The structure of the neurotoxin-associated protein HA33/A from Clostridium botulinum suggests a reoccurring beta-trefoil fold in the progenitor toxin complex.

The hemagglutinating protein HA33 from Clostridium botulinum is associated with the large botulinum neurotoxin secreted complexes and is critical in toxin protection, internalization, and possibly activation. We report the crystal structure of serotype A HA33 (HA33/A) at 1.5 A resolution that contains a unique domain organization and a carbohydrate recognition site. In addition, sequence alignments of the other toxin complex components, including the neurotoxin BoNT/A, hemagglutinating protein HA17/A, and non-toxic non-hemagglutinating protein NTNHA/A, suggests that most of the toxin complex consists of a reoccurring β-trefoil fold.
Pricing, market coverage and capacity: Can green and brown products co-exist?

Abstract Environmental strains are causing consumers to trade up to greener alternatives and many brown products are losing market coverage to premium-priced green rivals. In order to tackle this threat, many companies currently offering only brown products are contemplating the launch of a green product to complement their product portfolio. This paper provides strategic insights into and tactical ramifications of expanding a brown product line with a new green product. Our analysis explicitly incorporates a segmented consumer market where individual consumers may value the same product differently, the economies of scale and the learning effects associated with new green products, and capacity constraints for the current production system. It is shown that a single pricing scheme for the new green product limits a firm’s ability to appropriate the value different customers will relinquish in a segmented market and/or to avoid cannibalization. A two-level pricing structure can diminish and even completely avoid the salience of cannibalization. However, when resources are scarce, a firm can never protect his products from the threat of cannibalization by just revising the pricing structure which can spell the end of his brown product’s presence in the market or preclude the firm from launching the green product. At this point, the degree of cannibalization is higher for the brown product when the green product offers a sufficiently differentiated proposition to green segment consumers.
Understanding the causes of hyperglycemia in burn patients.

DOI of original article: 10.1016/j.jss.2012.0 * Corresponding author. Department of Surge Center, 10 Union Square East, Suite 2M, New E-mail address: mleitman@chpnet.org (I. 0022-4804/$ e see front matter a 2013 Elsev doi:10.1016/j.jss.2012.03.042 Hyperglycemia is commonly encountered in the critically ill patient. Although this is believed to be an adaptive stress response, hyperglycemia is in fact correlated with adverse outcomes [1]. Accordingly, critically ill patients are believed to benefit from enhanced glucose control. Several randomized controlled trials (RCTs) of strict glucose control with insulin therapy have been performed, most notably the 2001 landmark study by Van den Berghe et al., which found that intensive insulin therapy to maintain glucose at 80e110 mg/dL significantly reduced morbidity and mortality in intensive care unit (ICU) patients [2]. However, subsequent RCTs have reported conflicting results [1]. A metaanalysis of RCTs concluded that only surgical ICU patients, not medical ICU patients, enjoyed the benefit of strict glycemic control [3]. The large multicenter NICESUGAR trial demonstrated that an intermediate glucose target (140e180 mg/dL) was ideal, and resulted in lower mortality than stricter control (80e110 mg/dL) [4]. At the present time, due to conflicting data, the optimal target glucose level remains unclear. These data have been extrapolated to burn patients, despite the fact that burn patients were underrepresented in the RCTs of glycemic control in the ICU. Hyperglycemia was
Incorporating epigenetic data into the risk assessment process for the toxic metals arsenic, cadmium, chromium, lead, and mercury: strategies and challenges

Exposure to toxic metals poses a serious human health hazard based on ubiquitous environmental presence, the extent of exposure, and the toxicity and disease states associated with exposure. This global health issue warrants accurate and reliable models derived from the risk assessment process to predict disease risk in populations. There has been considerable interest recently in the impact of environmental toxicants such as toxic metals on the epigenome. Epigenetic modifications are alterations to an individual's genome without a change in the DNA sequence, and include, but are not limited to, three commonly studied alterations: DNA methylation, histone modification, and non-coding RNA expression. Given the role of epigenetic alterations in regulating gene and thus protein expression, there is the potential for the integration of toxic metal-induced epigenetic alterations as informative factors in the risk assessment process. In the present review, epigenetic alterations induced by five high priority toxic metals/metalloids are prioritized for analysis and their possible inclusion into the risk assessment process is discussed.
Alpha Power Gates Relevant Information during Working Memory Updating

Human working memory (WM) is inherently limited, so we must filter out irrelevant information in our environment or our mind while retaining limited important relevant contents. Previous work suggests that neural oscillations in the alpha band (8–14 Hz) play an important role in inhibiting incoming distracting information during attention and selective encoding tasks. However, whether alpha power is involved in inhibiting no-longer-relevant content or in representing relevant WM content is still debated. To clarify this issue, we manipulated the amount of relevant/irrelevant information using a task requiring spatial WM updating while measuring neural oscillatory activity via EEG and localized current sources across the scalp using a surface Laplacian transform. An initial memory set of two, four, or six spatial locations was to be memorized over a delay until an updating cue was presented indicating that only one or three locations remained relevant for a subsequent recognition test. Alpha amplitude varied with memory maintenance and updating demands among a cluster of left frontocentral electrodes. Greater postcue alpha power was associated with the high relevant load conditions (six and four dots cued to reduce to three relevant) relative to the lower load conditions (four and two dots reduced to one). Across subjects, this difference in alpha power was correlated with condition differences in performance accuracy. In contrast, no significant effects of irrelevant load were observed. These findings demonstrate that, during WM updating, alpha power reflects maintenance of relevant memory contents rather than suppression of no-longer-relevant memory traces.
Evaluators of image reconstruction algorithms

An image reconstruction algorithm is supposed to present an image that contains medically relevant information that exists in a cross section of the human body. There is an enormous variety of such algorithms. The question arises: Given a specific medical problem, what is the relative merit of two image reconstruction algorithms in presenting images that are helpful for solving the problem? An approach to answering this question with a high degree of confidence is that of ROC analysis of human observer performance. The problem with ROC studies using human observers is their complexity (and, hence, cost). To overcome this problem, it has been suggested to replace the human observer by a numerical observer. An even simpler approach is by the use of distance metrics, such as the root mean squared distance, between the reconstructed images and the known originals. For any of these approaches, the evaluation should be done using a sample set that is large enough to provide us with a statistically significant result. We concentrate in this paper on the numerical observer approach, and we reintroduce in this framework the notion of the Hotelling Trace Criterion, which has recently been proposed as an appropriate evaluator of imaging systems. We propose a definite strategy (based on linear abnormality-index functions that are optimal for the chosen figure of merit) for evaluating image reconstruction algorithms. We give details of two experimental studies that embody the espoused principles. Since ROC analysis of human observer performance is the ultimate yardstick for system assessment, one justifies a numerical observer approach by showing that it yields “similar” results to a human observer study. Also, since simple distance metrics are computationally less cumbersome than are numerical observer studies, one would like to replace the latter by the former, whenever it is likely to give “similar” results. We discuss approaches to assigning a numerical value to the “similarity” of the results produced by two different evaluators. We introduce a new concept, called rank-ordering nearness, which seems to provide us with a promising approach to experimentally determining the similarity of two evaluators of image reconstruction algorithms.
Phylogenetic comparison of the myxosporea based on an actin cDNA isolated from Myxobolus cerebralis.

ABSTRACT The full-length actin gene from Myxobolus cerebralis (Mcer Act-1), the first characterized from representatives in the phylum Myxozoa, encodes a 378-amino acid polypeptide with an estimated molecular weight of 41,580-Da. A phylogenetic comparison found M. cerebralis to branch outside the metazoans. This finding contrasts with previous reports that suggest an evolutionary affinity of the Myxozoa with either the Bilateria or Cnidaria.
Fatal Aplastic Anemia Following Topical Administration of Ophthalmic Chloramphenicol

A 73-year-old woman died of aplastic anemia less than two months after undergoing cataract extraction and beginning topical therapy with chloramphenicol. The first signs of pancytopenia began within one month of the surgery. The pattern of the aplastic anemia was associated with an idiosyncratic response to chloramphenicol. This was the second report of fatal aplastic anemia after topical treatment with chloramphenicol for ocular conditions, although two cases of reversible bone marrow hypoplasia have also been reported. Any other suspected cases of ocular toxicity associated with topically applied chloramphenicol should be reported to the National Registry of Drug-Induced Ocular Side Effects, Oregon Health Sciences University, Portland, OR 97201.
Ag–Cu–Ti Braze Materials for Sealing SOFCs

Two Ag-Cu-Ti brazing alloy compositions were studied as gas seals for solid oxide fuel cells (SOFCs). Yttria-stabilized zirconia pellets were bonded using Ag-35.25Cu-1.75Ti (Cusil-ABA) or Ag-20.1Cu-1.0Ti (average composition; Ag-Cusil). Both as-brazed filler metals contained metallic Ag and Cu phases, along with continuous titanium oxide layers at the filler metal-zirconia interfaces. The brazed joints were then aged at 700°C for up to 100 h in air or while separating H 2 and air atmospheres. After annealing in air for 100 h at 700°C, degradation in microstructure and hermeticity was more pronounced in Cusil-ABA. However, in H 2 -air atmosphere, Cusil-ABA performed better than Ag-Cusil. Ag-Cusil aged in H 2 air delaminated from zirconia and its microstructure showed large interconnected pores in Ag-rich regions. The results were confirmed by single-cell tests using each filler metal as a gas seal. Observations of the post-test Cusil-ABA microstructure revealed little degradation. These results indicate that Cusil-ABA is better suited than Ag-Cusil as a SOFC gas seal.
An explanation of closed-flux formation and sustainment using coaxial helicity injection on HIT-II

An explanation of the closed-flux operation on HIT-II is given. This method of operation generated flux amplification and closed flux on HIT-II without the presence of n = 1 or any large amplitude mode as measured from the outside shell. The method of operating also prevents hard absorber arcs and maximizes the toroidal current.
Interactions between two β-sheets energetics of β/β packing in proteins

The analysis of the interactions between regularly folded segments of the polypeptide chain contributes to an understanding of the energetics of protein folding. Conformational energy-minimization calculations have been carried out to determine the favorable ways of packing two right-twisted beta-sheets. The packing of two five-stranded beta-sheets was investigated, with the strands having the composition CH3CO-(L-Ile)6-NHCH3 in one beta-sheet and CH3CO-(L-Val)6-NHCH3 in the other. Two distinct classes of low-energy packing arrangements were found. In the class with lowest energies, the strands of the two beta-sheets are aligned nearly parallel (or antiparallel) with each other, with a preference for a negative orientation angle, because this arrangement corresponds to the best complementary packing of the two twisted saddle-shaped beta-sheets. In the second class, with higher interaction energies, the strands of the two beta-sheets are oriented nearly perpendicular to each other. While the surfaces of the two beta-sheets are not complementary in this arrangement, there is good packing between the corner of one beta-sheet and the interior part of the surface of the other, resulting in a favorable energy of packing. Both classes correspond to frequently observed orientations of beta-sheets in proteins. In proteins, the second class of packing is usually observed when the two beta-sheets are covalently linked, i.e. when a polypeptide strand passes from one beta-sheet to the other, but we have shown here that a large contribution to the stabilization of this packing arrangement arises from noncovalent interactions.
Reactions of symmetrical and unsymmetrical disilanes in the presence of Cp2MCl2/nBuLi (M = Ti, Zr, Hf)

Abstract The reactions of disilanes with catalytic quantities of Cp2MCl2/n BuLi (M = Ti, Zr) and cis-cyclooctene in a disilane/cyclooctene/metal ratio of approximately 30: ≥ 30: 1 exhibited rapid formation of monosilanes and trisilanes. The product distributions produced from H(PhMeSi)2H, H(BuMeSi)2H (symmetrical disilanes) and from HPh2SiSiPhMeH, HPhMeSiSiMe2H, HPhMeSiSiPrMeH and HPh2SiSiPhH2 (unsymmetrical disilanes) were determined by GCMS in all cases and the trisilanes from HPh2SiSiPhMeH and HPhMeSiSiMe2H were isolated and characterized spectroscopically. Major and minor isomers of Ph4Me2Si3H2 and Ph5MeSi3H2 (formed from HPh2SiSiPhMeH) and of PhMe5Si3H2 and Ph2Me4Si3H2 (formed from HPhMeSiSiMe2H) were identified. Analysis of the product distribution in these reactions indicated that both SiSi bond cleavage and SiH dehydrocoupling of the starting disilane occurs. Rationalization of the product distributions and apparent isomer preferences through both σ-bond metathesis steps and metal silylene intermediates is presented. The rapid reaction of the SiSi bond in H(SiPhMe)xH was found to be characteristic of the disilane and occurred only to a minor extent in the trisilane and was absent in the tetrasilane.
The Invalidity of Disclaimers about the Effects of Social Feedback on Self-Esteem

Despite the fact that several theories suggest that people's self-esteem is affected by social approval and disapproval, many individuals steadfastly maintain that how other people regard them has no effect on how they feel about themselves. To examine the validity of these beliefs, two experiments compared the effects of social approval and disapproval on participants who had indicated either that their self-esteem is affected by how other people evaluate them or that their self-esteem is unaffected by interpersonal evaluation. Results of both studies converged to show that approval and disapproval clearly affected the self-esteem of even those individuals who denied that social evaluations affected their feelings about themselves.
Yield-aware hierarchical optimization of large analog integrated circuits

Hierarchical optimization using building circuit block pareto performance models is an efficient and well established approach for optimizing the nominal performances of large analog circuits. However, the extension to yield-aware hierarchical methodology, as dictated by the need for safeguarding chip manufacturability in scaled technologies, is completely nontrivial. We address two fundamental difficulties in achieving such a methodology: yield-aware pareto performance characterization at the building block level and yield-aware system-level optimization problem formulation. It is shown that our approach is not only able to effectively capture the block performance trade-offs at different yield levels, but also correctly formulate the whole system yield and efficiently perform system-level optimization in presence of process variations. Our approach extends the efficiency of hierarchical analog optimization, enjoyed for improving nominal circuit performances, to yield-aware optimization. Our methodology is demonstrated by the hierarchical optimization of a phased locked loop (PLL) consisting of multiple circuit blocks.
Finite phase transitions in countable abelian groups

Let A be an infinite set that generates a group G. The sphere SA(r) is the set of elements of G for which the word length with respect to A is exactly r. We say G admits all finite transitions if for every r ≥ 2 and every finite symmetric subset \({W \subset G{\setminus}\{e\}}\), there exists an A with SA(r) = W. In this paper we determine which countable abelian groups admit all finite transitions. We also show that \({\mathbb{R}^n}\) and the finitary symmetric group on \({\mathbb{N}}\) admit all finite transitions.
Stability of silorane dental monomers in aqueous systems.

Summary Siloranes (silicon-based monomers with oxirane functionality) are investigated as matrix resins for new low shrinkage/stress dental composites. Compounds containing oxirane groups are known to be reactive with water, which could impart instability to the composite. Objective To test the stability of siloranes by measuring changes in the chemical structure of the oxirane group in aqueous environments. Methods Two siloranes (PH-SIL and TET-SIL) and their 1:1 mixture (SIL-MIX) were evaluated ( n =2–3). Siloranes were mixed in aqueous solutions with and without 1% tetrahydrofuran (THF) containing either liver esterase or epoxide hydrolase at pH 7.4, or dilute HCl at pH 1.4. The stability of conventional dioxiranes 3,4-epoxycyclohexyl-methyl-3,4-epoxycyclohexane carboxylate (ECHM-ECHC), and bisphenol A diglycidyl ether (BADGE) were also monitored under similar conditions. NMR was used to estimate the extent of reaction and give structural information about reaction products. Results Siloranes were found to be stable for 24 h in all aqueous environments tested. In contrast, ECHM-ECHC reacted at pH 1.4 to form species containing oxirane, ester, hydroxyl and carboxylic acid groups. Water hydrolyzed the ester group of ECHM-ECHC in the presence of liver esterase. In the presence of epoxide hydrolase, BADGE oxirane groups were hydrolyzed to diols, hydrolysis ranged from 0 to 34% depending on the aqueous environment. Conclusion The stability and insolubility of siloranes in biological fluid simulants suggests that these may be more suitable for use in the oral environment than conventional oxirane-functional monomers.
Deliberate Learning in Health Care: The Effect of Importing Best Practices and Creative Problem Solving on Hospital Performance Improvement

This article examines the effect on quality improvement of two common but distinct approaches to organizational learning: importing best practices (an externally oriented approach rooted in learning by imitating others’ best practices) and internal creative problem solving (an internally oriented approach rooted in learning by experimenting with self-generated solutions). We propose that independent and interaction effects of these approaches depend on where organizations are in their improvement journey – initial push or later phase. We examine this contingency in hospitals focused on improving treatment time for patients with heart attacks. Our results show that importing best practices helps hospitals achieve initial phase but not later phase improvement. Once hospitals enter the later phase of their efforts, however, significant improvement requires creative problem solving as well. Together, our results suggest that importing best practices delivers greater short-term improvement, but continued improvement depends on creative problem solving.
Serum/glucocorticoid-regulated kinase 1 expression in primary human prostate cancers.

BACKGROUND Serum/glucocorticoid-regulated kinase 1 (SGK1), a known target of the androgen receptor (AR) and glucocorticoid receptor (GR), is reported to enhance cell survival. This study sought to better define the role of SGK1 and GR in prostate cancer. METHODS Immunohistochemistry was performed for AR, GR, and SGK1 on primary prostate cancers (n = 138) and 18 prostate cancers from patients treated with androgen deprivation therapy. Relative staining intensity was compared utilizing a Fisher's exact test. Univariate analyses were performed using log-rank and chi-squared tests to evaluate prostate cancer recurrence with respect to SGK1 expression. RESULTS SGK1 expression was strong (3+) in 79% of untreated cancers versus 44% in androgen-deprived cancers (P = 0.003). Conversely, GR expression was present in a higher proportion of androgen-deprived versus untreated cancers (78% vs. 38%, P = 0.002). High-grade cancers were nearly twice as likely to have relatively low (0 to 2+) SGK1 staining compared to low-grade cancers (13.8% vs. 26.5%, P = 0.08). Low SGK1 expression in untreated tumors was associated with increased risk of cancer recurrence (adjusted log-rank test P = 0.077), 5-year progression-free survival 47.8% versus 72.6% (P = 0.034). CONCLUSIONS SGK1 expression is high in most untreated prostate cancers and declines with androgen deprivation. However, these data suggest that relatively low expression of SGK1 is associated with higher tumor grade and increased cancer recurrence, and is a potential indicator of aberrant AR signaling in these tumors. GR expression increased with androgen deprivation, potentially providing a mechanism for the maintenance of androgen pathway signaling in these tumors. Further study of the AR/GR/SGK1 network in castration resistance. Prostate 72:157–164, 2012. © 2011 Wiley Periodicals, Inc.
Moments of ranked discrete variables with an application to independent poisson variates

This paper presents a method for computing moments of ranked discrete variates. The method is based on a recursive relationship between the moments of the rth order statistic and the moments of the extreme order statistics. Bounds on the estimated moments are constructed as a function of truncation error and computational round-off errors. The method is illustrated with independent Poisson variates where the mean and variance of the smallest and largest of n ranked Poisson variates for n = 1(1)20 and Poisson parameter λ = 1(1)10 are computed. An approximation for the mean of an ordered Poisson variate is presented.
Magnetic resonance imaging of abdominal pain during pregnancy.

AbstractThe objective of this review is to demonstrate magnetic resonance imaging as an important adjunct to ultrasound and computed tomography in the evaluation of the pregnant patient with abdominal pain. With the advent of ultrafast T2-weighted pulse sequences, fetal and bowel motion cause minima
Incorporating fault debugging activities into software reliability models: a simulation approach

A large number of software reliability growth models have been proposed to analyse the reliability of a software application based on the failure data collected during the testing phase of the application. To ensure analytical tractability, most of these models are based on simplifying assumptions of instantaneous & perfect debugging. As a result, the estimates of the residual number of faults, failure rate, reliability, and optimal software release time obtained from these models tend to be optimistic. To obtain realistic estimates, it is desirable that the assumptions of instantaneous & perfect debugging be amended. In this paper we discuss the various policies according to which debugging may be conducted. We then describe a rate-based simulation framework to incorporate explicit debugging activities, which may be conducted according to the different debugging policies, into software reliability growth models. The simulation framework can also consider the possibility of imperfect debugging in conjunction with any of the debugging policies. Further, we also present a technique to compute the failure rate, and the reliability of the software, taking into consideration explicit debugging. An economic cost model to determine the optimal software release time in the presence of debugging activities is also described. We illustrate the potential of the simulation framework using two case studies.
Multi-objective optimization of HVAC system with an evolutionary computation algorithm

A data-mining approach for the optimization of a HVAC (heating, ventilation, and air conditioning) system is presented. A predictive model of the HVAC system is derived by data-mining algorithms, using a dataset collected from an experiment conducted at a research facility. To minimize the energy while maintaining the corresponding IAQ (indoor air quality) within a user-defined range, a multi-objective optimization model is developed. The solutions of this model are set points of the control system derived with an evolutionary computation algorithm. The controllable input variables — supply air temperature and supply air duct static pressure set points — are generated to reduce the energy use. The results produced by the evolutionary computation algorithm show that the control strategy saves energy by optimizing operations of an HVAC system.
Food-Restricting First Generation Juvenile Female Hamsters (Mesocricetus Auratus) Affects Sex Ratio and Growth of Third Generation Offspring

Female hamsters (Generation 1) were fed ad libitum or were food-restricted to 65-75% of the amount consumed by controls during their first 50 days of life. Subjects were mated at 91 days of age. Their offspring (Generation 2) were fed ad libitum throughout the experiment, and female offspring were also mated at 91 days of age. Generation 3 litters were monitored every fifth day from birth until Day 25 post partum for litter size, sex ratio, and pup weights. Although there were no significant differences in Generation 3 litter sizes at birth, litters descended from food-restricted Generation I females (Group R) were significantly smaller on Days 5-25 than litters descended from control Generation 1 females (Group A). Sex ratios remained significantly greater in Group A than in Group R litters from birth to Day 25 but did not vary over time, suggesting similar postpartum mortality rates for both male and female pups. Weights of Generation 3 male and female pups did not vary significantly within treatments at any time. Group A males weighed significantly more than Group R males from birth through Day 25, but weights of Group A and Group R females were always similar. Food restriction early in life may have long-term consequences on sex ratios of subsequent generations in hamsters.
Electrophysiologic Studies in a Patient with Atrial Flutter and 1:1 Atrioventricular Conduction

Intracardiac electrophysiologic studies were performed in a patient having paroxysms of atrial flutter with 1:1 atrioventricular (A-V) conduction. Although duration of conduction intervals was normal during sinus rhythm, the atrio-His (A-H) interval did not show the expected increase when the atria were stimulated at progressively higher rates. The results of pacing with the extrastimulus technique also indicated that the refractory periods of the A-H tissues were shorter than normal. Yet, intravenously administered ouabain produced a significant increase in these refractory periods. The findings in this case are compatible with a partial A-V nodal bypass with a shorter refractory period than the A-V node or with an A-V node with unusual capacity for rapid conduction. The response to ouabain therapy was that of A-V nodal tissues.
Effect of Afterload on Force-Velocity Relations and Contractile Element Work in the Intact Dog Heart

The effects of heightened afterload on force-velocity relations and on contractile element work of single systoles were examined in the intact dog heart. The force-velocity curve described during the course of a normal systole represents a composite of curves, each with its own projected isometric force determined by instantaneous changes in fiber length. During the first systole following an afterload intervention, reciprocal changes in force and velocity were observed together with an extension of the projected isometric-force. The effect of afterload on contractile element work was determined by: (1) the direction and magnitude of the afterload, and (2) the afterload of the control beat itself. When the control beat was lightly loaded, an increase in afterload increased contractile element work by two additive mechanisms: (1) an increase in mean isometric force, and (2) a shift of force-velocity relations to positions of greater power and work production. In normally loaded control beats, an increase in afterload resulted in a decrease in contractile element work, despite the fact that mean isometric force was increased. In this instance, force-velocity relations were shifted to positions where less power and work could be achieved. Thus, the normal systole appears to function at the apex of the contractile element work-load curve (near 60% of the isometric load). Evidence is presented which suggests that the apparent maximum active state of the entire left ventricle is generally achieved within 30 to 50 msec after the onset of pressure rise, and that its decay is accompanied by abrupt divergence of the force-velocity relations from the inverse curve of that beat. A sudden increase in afterload does not appear to influence the duration of the maximum active state, although the duration of positive contractile element work is shortened and that of negative contractile element work prolonged.
Designing Effective Health Communications: A Meta-Analysis:

Abstract A meta-analysis of health communications examines the influence of 22 tactics and six individual characteristics on intentions to comply with health recommendations. The analysis indicates that message tactics have a significant influence on intentions toward health-related recommendations even after the authors account for individual differences. In addition, the authors examine when message tactics interact with individual characteristics to determine intentions. The results, which are based on 60 studies involving nearly 22,500 participants, show that there is significant opportunity to tailor health communications more efficiently to different market segments.
Haploinsufficiency of Apc leads to ineffective hematopoiesis.

Loss of a whole chromosome 5 or a deletion of the long arm of chromosome 5, −5/del(5q), is a recurring abnormality in myeloid neoplasms. The APC gene is located at chromosome band 5q23, and is deleted in more than 95% of patients with a −5/del(5q), raising the question of whether haploinsufficiency of APC contributes to the development of myeloid neoplasms with loss of 5q. We show that conditional inactivation of a single allele of Apc in mice leads to the development of severe anemia with macrocytosis and monocytosis. Further characterization of the erythroid lineage revealed that erythropoiesis is blocked at the early stages of differentiation. The long-term hematopoietic stem cell (LT-HSC) and short-term HSC (ST-HSC) populations are expanded in Apc-heterozygous mice compared with the control littermates; however, the HSCs have a reduced capacity to regenerate hematopoiesis in vivo in the absence of a single allele of Apc. Apc heterozygous myeloid progenitor cells display an increased frequency of apoptosis, and decreased in vitro colony-forming capacity, recapitulating several characteristic features of myeloid neoplasms with a −5/del(5q). Our results indicate that haploinsufficiency of Apc impairs hematopoiesis, and raise the possibility that loss of function of APC contributes to the development of myelodysplasia.
High Performance Liquid Chromatographic Assay for Papaverine in Plasma

AbstractA simple and sensitive assay for papaverine in plasma was developed. Plasma was extracted into n-heptane and back extracted into 0.1 N HCl. An aliquot of 0.1 N HC1 was injected onto a reversed-phase column. The mobile phase consisted of 33% acetonitrile in 0.05 M phosphate buffer, pH 3.0, at a flow rate of 1.6 ml/min. The retention times of papaverine and the internal standard (diphenylhy-dramine hydrochloride) were 4.0 and 7.0 minutes respectively. The coefficient of variation over 2-50 nanogram/ml range for spiked samples (n = 6) was 9.9% suitability of this method for plasma sample analysis from a bioavailability study was demonstrated.
Tocopherols inhibit oxidative and nitrosative stress in estrogen-induced early mammary hyperplasia in ACI rats.

Oxidative stress is known to play a key role in estrogen-induced breast cancer. This study assessed the chemopreventive activity of the naturally occurring γ-tocopherol-rich mixture of tocopherols (γ-TmT) in early stages of estrogen-induced mammary hyperplasia in ACI rats. ACI rats provide an established model of rodent mammary carcinogenesis due to their high sensitivity to estrogen. Female rats were implanted with 9 mg of 17β-estradiol (E2) in silastic tubings and fed with control or 0.3% γ-TmT diet for 1, 3, 7 and 14 days. γ-TmT increased the levels of tocopherols and their metabolites in the serum and mammary glands of the rats. Histological analysis revealed mammary hyperplasia in the E2 treated rats fed with control or γ-TmT diet. γ-TmT decreased the levels of E2-induced nitrosative and oxidative stress markers, nitrotyrosine and 8-oxo-dG, respectively, in the hyperplastic mammary tissues. 8-Isoprostane, a marker of oxidative stress in the serum, was also reduced by γ-TmT. Noticeably, γ-TmT stimulated Nrf2-dependent antioxidant response in the mammary glands of E2 treated rats, evident from the induced mRNA levels of Nrf2 and its downstream antioxidant enzymes, superoxide dismutase, catalase and glutathione peroxidase. Therefore, inhibition of nitrosative/oxidative stress through induction of antioxidant response is the primary effect of γ-TmT in early stages of E2-induced mammary hyperplasia. Due to its cytoprotective activity, γ-TmT could be a potential natural agent for the chemoprevention of estrogen-induced breast cancer.
Carbon Nanomaterials for Next-Generation Interconnects and Passives: Physics, Status, and Prospects

This paper reviews the current state of research in carbon-based nanomaterials, particularly the one-dimensional (1-D) forms, carbon nanotubes (CNTs) and graphene nanoribbons (GNRs), whose promising electrical, thermal, and mechanical properties make them attractive candidates for next-generation integrated circuit (IC) applications. After summarizing the basic physics of these materials, the state of the art of their interconnect-related fabrication and modeling efforts is reviewed. Both electrical and thermal modeling and performance analysis for various CNT- and GNR-based interconnects are presented and compared with conventional interconnect materials to provide guidelines for their prospective applications. It is shown that single-walled, double-walled, and multiwalled CNTs can provide better performance than that of Cu. However, in order to make GNR interconnects comparable with Cu or CNT interconnects, both intercalation doping and high edge-specularity must be achieved. Thermal analysis of CNTs shows significant advantages in tall vias, indicating their promising application as through-silicon vias in 3-D ICs. In addition to on-chip interconnects, various applications exploiting the low-dimensional properties of these nanomaterials are discussed. These include chip-to-packaging interconnects as well as passive devices for future generations of IC technology. Specifically, the small form factor of CNTs and reduced skin effect in CNT interconnects have significant implications for the design of on-chip capacitors and inductors, respectively.
The Relationship Between Personalized Classroom Talk and Teacher Effectiveness Ratings: Some Research Results

This article presents and discusses an observational system that discriminates between personal and impersonal (or neutral) verbal behavior of teachers and students in the foreign language classroom, ascertains the usability of the instrument for the collection of data on the nature of such interactions, determines the extent to which two groups of teachers at two large state universities are personalizing their classroom environment, and reports on preliminary findings on the relationship of these in-class behavior variables and the perceptions of teacher effectiveness by both supervisors and students. Results obtained in the two studies indicate that teacher effectiveness ratings obtained from supervisors and students are significantly correlated with the degree to which verbal interactions in the language classroom are personalized.
EXCLUDED POSSIBILITIES OF GEOMETRODYNAMICAL ANALOG TO ELECTRIC CHARGE.

in 1956, J. A. Wheeler and C. W. Misner [I] showed in some detail that the existence of charges in the world need not be associated with sources in the electromagnetic field equations, but rather could be described as a consequence of Maxwell's free field equations (i.e. Ffj,,:~,l =0 and F~'";,--0) in a space with a multiply connected topology [2]. The electric lines of force can be ' tra?ped' in the topological structure of space, with the number of trapped lines of force being directly proportional to the charge associated with that field. To make this idea clearer, let us examine a simple example of a multiply connected, or 'v, ormhole' topology trapping electric lines of force. If the interiors of two solid spheres of equal radius are removed from an ordinary three dimensional Euclidean space, and' the appropriate points On the surfaces of the two spheres are identified, we obtain a "wormhole' in our space. If now we imagine that the t**o spheres had been conducting, one having charge q and the other charge q . and that the resultant electric field were fixed during the above reconstruction of our space, we discover that the resultant electric field everywhere obeys the free field equations. However, for an)'one located outside the cutaway portions of the space, there wouk! be no way of telling that the charges were no longer there. For example, integrating the field over any closed surface surrounding one of the wormhole mouths would tell him that the surface still enclosed a charge q. We have created, in Wheeler's words, 'charge without charge'. Due to the symmetry in Maxwell's equations between E and B, magnetic lines of force could similarly be trapped by the topology, creating magnetic charges, ilowever, these have never been observed in nature [3l. Wc theretore make the natural assumption that magnetic lines of force cannot be trapped in a multiply-connected topology. The above concepts can bc put into a rigorous mathematical form [4]. The electromagnetic tensors/-'*~ and ~,,~,~,f'p" are curl free antisymmetric I~ensors, and as such coffespond to closed differential 2+formsfand *f(i.e
How much of the placebo 'effect' is really statistical regression?

Statistical regression to the mean predicts that patients selected for abnormalcy will, on the average, tend to improve. We argue that most improvements attributed to the placebo effect are actually instances of statistical regression. First, whereas older clinical trials susceptible to regression resulted in a marked improvement in placebo-treated patients, in a modern series of clinical trials whose design tended to protect against regression, we found no significant improvement (median change 0.3 per cent, p greater than 0.05) in placebo-treated patients. Secondly, regression can yield sizeable improvements, even among biochemical tests. Among a series of 15 biochemical tests, theoretical estimates of the improvement due to regression by selection of patients as high abnormals (i.e. 3 standard deviations above the mean) ranged from 2.5 per cent for serum sodium to 26 per cent for serum lactate dehydrogenase (median 10 per cent); empirical estimates ranged from 3.8 per cent for serum chloride to 37.3 per cent for serum phosphorus (median 9.5 per cent). Thus, we urge caution in interpreting patient improvements as causal effects of our actions and should avoid the conceit of assuming that our personal presence has strong healing powers.