cssi/SciSciGPT-SciSciNet huggingface dataset:
Evolución del gobierno corporativo en Chile desde la ley de OPASs

El texto arrastra al lector a debates academicos imbricados, ya que el contenido no es meramente teorico, sino que, a traves de estudios empiricos, en primer lugar, evalua la incorporacion de los Principios de GC de la OCDE en la normativa chilena; y, en segundo lugar, estudia la aplicacion de dichos principios por Sociedades Anonimas Abiertas (cotizadas en Bolsa) y la implicancia que dicha praxis tiene en el valor de la empresa y, por rebote, en el Mercado de Capitales. La hipotesis planteada, en el sentido que en el Mercado de Capitales chileno el buen gobierno corporativo basado en disposiciones de la OCDE –medido mediante un indice de cumplimiento– esta relacionado positivamente con el valor de la empresa, es parcialmente demostrada. Se concluye que, en el periodo de estudio, el factor menos importante en el valor de la empresa es la calidad del Gobierno Corporativo.
Epigenetic changes induced by Bacteroides fragilis toxin (BFT)

Abstract Enterotoxigenic Bacteroides fragilis (ETBF) is a gram negative, obligate anaerobe member of the gut microbial community in up to 40% of healthy individuals. This bacterium is found more frequently in people with colorectal cancer (CRC) and causes tumor formation in the distal colon of mice heterozygous for the adenomatous polyposis coli gene (Apc+/−); tumor formation is dependent on ETBF-secreted Bacteroides fragilis toxin (BFT). Though some of the immediate downstream effects of BFT on colon epithelial cells (CECs) are known, we still do not understand how this potent exotoxin causes changes in CECs that lead to tumor formation and growth. Because of the extensive data connecting alterations in the epigenome with tumor formation, initial experiments attempting to connect BFT-induced tumor formation with methylation in CECs have been performed, but the effect of BFT on other epigenetic processes, such as chromatin structure, remains unexplored. Here, the changes in chromatin accessibility (ATAC-seq) and gene expression (RNA-seq) induced by treatment of HT29/C1 cells with BFT for 24 and 48 hours is examined. Our data show that several genes are differentially expressed after BFT treatment and these changes correlate with changes in chromatin accessibility. Also, sites of increased chromatin accessibility are associated with a lower frequency of common single nucleotide variants (SNVs) in CRC and with a higher frequency of common differentially methylated regions (DMRs) in CRC. These data provide insight into the mechanisms by which BFT induces tumor formation. Further understanding of how BFT impacts nuclear structure and function in vivo is needed. Importance Colorectal cancer (CRC) is a major public health concern; there were approximately 135,430 new cases in 2017, and CRC is the second leading cause of cancer-related deaths for both men and women in the US (1). Many factors have been linked to CRC development, the most recent of which is the gut microbiome. Pre-clinical models support that enterotoxigenic Bacteroides fragilis (ETBF), among other bacteria, induce colon carcinogenesis. However, it remains unclear if the virulence determinants of any pro-carcinogenic colon bacterium induce DNA mutations or changes that initiate clonal CEC expansion. Using a reductionist model, we demonstrate that BFT rapidly alters chromatin structure and function consistent with capacity to contribute to CRC pathogenesis.
Serine-Threonine Kinase Receptor Associate Protein (STRAP) Confers Stemness in Neuroblastoma

Background: Serine-threonine kinase receptor associated protein (STRAP) is a scaffolding protein that has been implicated in tumor growth and metastasis. The role of STRAP in neuroblastoma (NB) has not been explored. Stem cell-like cancer cells (SCLCCs) are believed to be responsible for tumor cell self-renewal and cancer recurrence. We sought to determine the role of STRAP in neuroblastoma SCLCCs maintenance. …
Recognizing the Clinical Sequelae of COVID-19 in Adults: COVID-19 Long-Haulers.

As the numbers of acute SARS-CoV-2 infections continue to rise, we are learning that symptoms do not resolve quickly in all patients. While it is not clear why some patients experience persistent symptoms, these individuals suffer. Long-hauler is the term that is associated with these persistent symptoms and a review of the literature provides information to nurse practitioners working in primary care about symptomatology, risk factors, and resources for disease management.
Reclaiming Media Credibility: Examining the Efficacy of Virtue Ethics in the Zambian Media

Tales of unethical reporting, conflict of interest, biases, and corruption characterize media practice in Zambia today. The advent of technology and the mushrooming of media houses have ironically magnified this trend. Such tendencies have compromised ethical reporting, thus undermining journalistic credibility. While some scholars call for a return to African ethics, others hanker for greater professionalism. This study offers an overview of the media in Zambia with Zambia National Broadcasting Corporation and the POST newspaper as its case study. The study looks at how virtue ethics would be effective in reclaiming media credibility. Using qualitative methods, data were collected via theoretical and methodological triangulation. Open-ended questions were designed and distributed among 10 Zambian journalists. The interviews were conducted within a period of one month. Findings indicated that media credibility in Zambia has reached unprecedented levels of suspicion and that virtue ethics, if well applied, would redeem the lost credibility.
Clinical outcomes of distal vaginal and vulvar cancer treated with image-guided brachytherapy

Purpose To evaluate treatment outcomes with image-guided brachytherapy (IGBT) for distal vaginal and vulvar cancers. Material and methods Women treated for distal vaginal or vulvar malignancies utilizing IGBT were retrospectively reviewed, and acute and late toxicities were retrospectively graded. Descriptive statistical analysis was performed. Results Eighteen patients were included, out of which, twelve patients (66.7%) were with primary disease of the distal vagina and vulva, most commonly squamous cell carcinoma of the vulva (n = 8, 66.7%), and six with recurrent disease, most commonly recurrent endometrial carcinoma (n = 5, 83.3%). All patients received external beam radiation (EBRT) to a median dose of 45 Gy in 25 fractions, followed by IGBT (range of 15 to 27.5 Gy in 3 to 5 fractions). Mean follow-up was 20.6 months. Mean dose to high-risk clinical target volume (HR-CTV) D90 was 72.4 Gy. Mean D2cc for the rectum, bladder, and urethra were 50 Gy, 50.6 Gy, and 62.9 Gy, respectively. Five patients (27.8%) recurred. Three patients (16.7%) had local recurrence, 1 patient (5.6%) had distant recurrence only, and 1 patient (5.6%) had simultaneous regional and distant recurrence. Grade 3 acute toxicities included 1 (5.6%) vaginal stenosis, 6 (33.3%) dermatitis/mucositis, 2 (11.1%) vaginal pain, and 1 (5.6%) vaginal/vulvar infection. Grade 3 late toxicities comprised 3 (17.7%) cases of vaginal pain and 1 (5.9%) skin/vaginal necrosis. There were no grade 4 or higher toxicities. Conclusions Definitive radiation therapy in the form of EBRT and IGBT provides meaningful loco-regional control in women with distal vaginal and vulvar cancers, with mainly skin and vaginal toxicity.
Gene expression profiles in developing nephrons using Lim1 metanephric mesenchyme-specific conditional mutant mice.

Background Lim1 is a homeobox gene that is essential for nephrogenesis. During metanephric kidney development, Lim1 is expressed in the nephric duct, ureteric buds, and the induced metanephric mesenchyme. Conditional ablation of Lim1 in the metanephric mesenchyme blocks the formation of nephrons at the nephric vesicle stage, leading to the production of small, non-functional kidneys that lack nephrons.
Dietary Conjugated Linoleic Acid (CLA) Attenuates Hepatic Steatosis by Modifying Stearoyl-CoA Desaturase (SCD-1) mRNA and Activity in High-Fat-Fed Rats

Non alcoholic hepatic steatosis is associated with obesity and may lead to insulin resistance. Isomers of CLA are naturally occurring dietary compounds with health promoting effects. The role of CLA in attenuating hepatic steatosis and hyperglycemia is complex. Here, we investigated the extent that CLA protects male Wistar rats from developing hepatic steatosis. Rats were fed a 20% fat diet for 4 weeks then changed to either control (CON) diet or CLA diet containing 6.5% soybean oil or 5% soybean oil plus 1.5% CLA respectively. After 4 weeks, CLA diet did not change food intake or body weight however fasting blood glucose (FBG) and hepatic triglycerides (TG) were significantly reduced compared to CON group. Reduced TG levels were associated with significantly lower SCD-1 mRNA levels measured by real time PCR and SCD-1 activity which was determined by gas chromatography. As the rate-limiting enzyme in the cellular biosynthesis of oleate and palmitoleate, SCD-1 activity is indicative of synthesis of components of TG, phospholipids and cholesterol. The effects of CLA on SCD-1 were independent of the adipocytokine, leptin, which was unchanged in rats fed CLA. Because leptin is known to suppress SCD-1, these data suggest CLA acts in part as a leptin mimetic. The mRNA levels of gluconeogenic enzymes were unchanged in the CLA fed group. Thus, the lower hepatic lipid accumulation may be modulated by SCD-1 independent of changes on adipose or leptin levels. We anticipate these hepatic effects explain the improvement of glucose levels in Wistar rats fed CLA. This work was supported by the USDA..
Optimal sampling in parallel magnetic resonance imaging

Parallel MR imaging methods like SMASH, SENSE etc. use multiple receiver coils to accelerate the imaging process by reducing the Fourier space sampling requirement. In this paper we show how one can optimally select the sampling locations based upon (1) knowledge of the statistics of the object being imaged and, (2) a statistical criterion for optimality determined by the application. In particular we show that the optimal uniform sample spacing is not necessarily an integer multiple of the Nyquist interval and depends upon the specific coil sensitivities and configuration.
Finding Specific Genes that Cause Autism: A Combination of Approaches Will Be Needed To Maximize Power.

Although autism is clearly inherited, it may be challenging to find the genes involved: The mechanism of inheritance is unknown, families with an autistic child are usually small, parent–child pairs are rare, and a fairly large number of genes may be involved, some or all of which may have a small effect on the phenotype. We discuss several strategies for finding genes, all of which may be used in combination to find the relevant genes.
Factors influencing the adsorption, desorption, and movement of pesticides in soil

Seven factors are known to influence the fate and behavior of pesticides in soil systems: (1) chemical decomposition, (2) photochemical decomposition, (3) microbial decomposition, (4) volatilization, (5) movement, (6) plant or organism uptake, and (7) adsorption. The phenomenon of adsorption-desorption directly or indirectly influences the magnitude of the effect of the other six factors. Adsorption, therefore, appears to be one of the major factors affecting the interactions occurring between pesticides and soil colloids.
EFFECT OF PH ON THE FORMATION OF EXOCELLULAR NUCLEASE IN AGING BROTH CULTURES OF SERRATIA MARCESCENS.

Eaves, George N. (Wayne State University College of Medicine, Detroit, Mich.) and Charles D. Jeffries. Effect of pH on the formation of exocellular nuclease in aging broth cultures of Serratia marcescens. J. Bacteriol. 85:1194–1196. 1963.—The formation of exocellular nuclease by Serratia marcescens occurred in the stationary phase of growth and was not associated with cell multiplication. An increase in specific enzymatic activity until the phase of autolysis suggested the selective secretion of the exocellular nuclease. The amount of enzyme accumulated was dependent upon the final pH attained by the culture medium, which was, in turn, related to the initial pH of the medium. The production of this nuclease was greatly favored by an alkaline pH.
Continuous Spatiotemporal Trajectory Joins

Given the plethora of GPS and location-based services, que- ries over trajectories have recently received much attention. In this paper we examine trajectory joins over streaming spatiotemporal data. Given a stream of spatiotemporal trajectories created by monitored moving objects, the outcome of a Continuous Spatiotemporal Trajectory Join(CSTJ) query is the set of objects in the stream, which have shown similar behavior over a query-specified time interval, relative to the current timestamp. We propose a novel indexing scheme for streaming spatiotemporal data and develop algorithms for CSTJ evaluation, which utilize the proposed indexing scheme and effectively reduce the computation cost and I/O operations. Finally, we present a thorough experimental evaluation of the proposed indexing structure and algorithms.
Estimation of population-level summaries in general semiparametric repeated measures regression models

This paper considers a wide family of semiparametric repeated measures regression models, in which the main interest is on estimating population-level quantities such as mean, variance, probabilities etc. Examples of our framework include generalized linear models for clustered/longitudinal data, among many others. We derive plug-in kernel-based estimators of the population level quantities and derive their asymptotic distribution. An exam- ple involving estimation of the survival function of hemoglobin measures in the Kenya hemoglobin study data is presented to demonstrate our methodology. This paper is about semiparametric regression models with repeated measures when the primary goal is to estimate a population quantity such as mean, variance, prob- ability, etc. We will construct estimators of these quantities which utilize the under- lying semiparametric structure of the model and derive their limiting distribution. The work is motivated by the following example: the Kenya hemoglobin data. The goal is to study the changes of hemoglobin over time during the first year of birth. The data set consists of 68 families with 2 children per family. For each child, 4 repeated measures are taken over time in the first year since birth: the time of visit varied from child to child. The factors include mother's age at child birth, child sex and placental parasitemia density (PDEN), a marker of malaria that could affect hemoglobin. To model these data, Lin and Carroll (2) considered a semiparametric model where the mother's age effect is modeled nonparametrically and (sex, PDEN) is modeled parametrically. The model is given by the repeated measures partially linear model Yijk = X T ijkβ0 + θ0(Zij) + ǫijk,
Phenotypes of hypofrontality in older female fragile X premutation carriers

Objective To investigate the nature of cognitive impairments and underlying brain mechanisms in older female fragile X premutation carriers with and without fragile X-associated tremor/ataxia syndrome (FXTAS). Methods Extensive neuropsychological testing and cognitive event-related brain potentials (ERPs; particularly, the auditory P300) were examined in 84 female participants: 33 fragile X premutation carriers with FXTAS (mean age = 62.8 years), 25 premutation carriers without FXTAS (mean age = 55.4 years), and 26 normal healthy controls (mean age = 59.3 years). Results Both premutation groups exhibited executive dysfunction on the Behavioral Dyscontrol Scale, with subtle impairments in inhibition and performance monitoring in female carriers without FXTAS, and more substantial deficits in FXTAS women. However, the female carrier group without FXTAS showed more pronounced deficiencies in working memory. Abnormal ERPs were recorded over the frontal lobes, where FXTAS patients showed both P300 amplitude reduction and latency prolongation, whereas only decreased frontal P300 amplitudes were found in carriers without FXTAS. These frontal P300 measures correlated with executive function and information processing speed. Interpretation The neuropsychological testing and ERP results of the present study provide support for the hypothesis that executive dysfunction is the primary cognitive impairment among older female premutation carriers both with and without FXTAS, although these deficits are relatively mild compared to those in FXTAS males. These findings are consistent with a synergistic effect of the premutation and aging on cognitive impairment among older female fragile X premutation carriers, even in those without FXTAS symptoms. Ann Neurol 2013;74:275–283
Degradation of cytochrome P-450 haem by carbon tetrachloride and 2-allyl-2-isopropylacetamide in rat liver in vivo and in vitro. Involvement of non-carbon monoxide-forming mechanisms.

Degradation of intrinsic hepatic [14C]haem was analysed as 14CO formation in living rats and in hepatic microsomal fractions prepared from these animals 16h after pulse-labelling with 5-amino[5-14C]laevulinic acid, a precursor that labels bridge carbons of haem in non-erythroid tissues. NADPH-catalysed peroxidation of microsomal lipids in vitro (measured as malondialdehyde) was accompanied by loss of cytochrome P-450 and microsome-associated [14C]haem (largely cytochrome P-450 haem), but little 14CO formation. No additional 14CO was formed when carbon tetrachloride and 2-allyl-2-isopropylacetamide were added to stimulate lipid peroxidation and increase loss of cytochrome P-450 [14C]haem. Because the latter effect persisted despite inhibition of lipid peroxidation with MnCl2 or phenyl-t-butylnitrone(a spin-trapping agent for free radicals), it was concluded that carbon tetrachloride, as reported for 2-allyl-2-isopropylacetamide, may promote loss of cytochrome P-450 haem through a non-CO-forming mechanism independent of lipid peroxidation. By comparison with breakdown of intrinsic haem, catabolism of [14C]methaemalbumin by microsomal haem oxygenase in vitro produced equimolar quantities of 14CO and bilirubin, although these catabolites reflected only 18% of the degraded [14C]haem. This value was increased to 100% by addition of MnCl2, which suggests that lipid peroxidation may be involved in degradation of exogenous haem to products other than CO. Phenyl-t-butylnitrone completely blocked haem oxygenase activity, which suggests that hydroxy free radicals may represent a species of active oxygen used by this enzyme system. After administration of carbon tetrachloride or 2-allyl-2-isopropylacetamide to labelled rats, hepatic [14C]haem was decreased and haem oxygenase activity was unchanged; however, 14CO excretion was either unchanged (carbon tetrachloride) or decreased (2-allyl-2-isopropylacetamide). These changes were unaffected by cycloheximide pretreatment. From the lack of parallel losses of cytochrome P-450 [14C]haem and 14CO excretion, one may infer that an important fraction of hepatic [14C]haem in normal rats is degraded by endogenous pathways not involving CO. We conclude that carbon tetrachloride and 2-allyl-2-isopropylacetamide accelerate catabolism of cytochrome P-450 haem through mechanisms that do not yield CO as an end product, and that are insensitive to cycloheximide and independent of haem oxygenase activity.
Accurate and robust line segment extraction by analyzing distribution around peaks in Hough space

Hough transform (HT) is a well-known technique for extracting lines. However, it is difficult for most existing HT methods to extract line segments robustly from complicated images, mainly because the influence from various objects other than line segments are not taken into account. This paper proposes an accurate and robust evaluator that dynamically removes contributions of backgrounds and analyzes voting patterns around peaks in the accumulator space. In the experiments, four peak detection algorithms are tested against seven images completely automatically. Results show that our method is superior to existing methods in terms of accuracy and robustness while there are no clear differences in execution time. The proposed evaluator detects peaks after the HT and hence it can be applied to any HT that keeps the basic characteristics of the voting process.
TREATMENT STAFF REFERRALS, PARTICIPATION EXPECTATIONS, AND PERCEIVED BENEFITS AND BARRIERS TO ADOLESCENT INVOLVEMENT IN 12-STEP GROUPS.

ABSTRACT Adolescents treated for substance use disorders (SUDs) appear to benefit from participation in Alcoholics Anonymous/Narcotics Anonymous (AA/NA). However, as compared with adults, fewer adolescents attend, and those who do attend do so less intensively and discontinue sooner. It is unknown whether this disparity is due to a lowered expectation for youth participation by the clinicians treating them, as they may adapt the adult-based model to fit a less-dependent cohort, or whether recommendations are similar to those of clinicians who work with adults and other factors are responsible. All clinical staff (N = 114) at 5 adolescent programs (3 residential, 2 outpatient) were surveyed anonymously about referral practices and other beliefs about 12-step groups. Staff rated AA/NA participation as very important and helpful to adolescent recovery and referral rates were uniformly high (M = 86%, SD = 28%). Desired participation frequency was over 3 times per week. The theoretical orientation and level of...
A thalamo‐cortico‐amygdala pathway mediates auditory fear conditioning in the intact brain

The neural substrates of fear conditioning in rats have been well characterized, with converging lines of evidence indicating that conditioned stimulus (CS) and unconditioned stimulus (US) information form a CS-US association in the amygdala. Auditory CS information can reach the amygdala via two routes: a direct thalamo-amygdala pathway, and an indirect thalamo-cortico-amygdala pathway. Although either pathway can fully support learning when the alternate pathway is disrupted, many studies to date have argued that the thalamo-amygdala pathway is the principal auditory CS pathway in intact brains. To test this hypothesis, we trained rats in auditory fear conditioning, and 24 h later lesioned either pathway, leaving the alternate pathway intact. Later, animals were tested for conditioned freezing to the auditory CS. We report that lesions of the thalamo-amygdala pathway produced severe but incomplete deficits in freezing during the tone retention test, while lesions of the thalamo-cortico-amygdala pathway completely abolished freezing during tone presentation. These results suggest that the thalamo-cortico-amygdala pathway is the principal auditory CS pathway when the brain is intact.
Behavioral sensitivity to interaural time differences in the rabbit.

Abstract An important cue for sound localization and separation of signals from noise is the interaural time difference (ITD). Humans are able to localize sounds within 1–2° and can detect very small changes in the ITD (10–20 μs). In contrast, many animals localize sounds with less precision than humans. Rabbits, for example, have sound localization thresholds of ∼22°. There is only limited information about behavioral ITD discrimination in animals with poor sound localization acuity that are typically used for the neural recordings. For this study, we measured behavioral discrimination of ITDs in the rabbit for a range of reference ITDs from 0 to ±300 μs. The behavioral task was conditioned avoidance and the stimulus was band-limited noise (500–1500 Hz). Across animals, the average discrimination threshold was 50–60 μs for reference ITDs of 0 to ±200 μs. There was no trend in the thresholds across this range of reference ITDs. For a reference ITD of ±300 μs, which is near the limit of the physiological window defined by the head width in this species, the discrimination threshold increased to ∼100 μs. The ITD discrimination in rabbits less acute than in cats, which have a similar head size. This result supports the suggestion that ITD discrimination, like sound localization [see Heffner, 1997. Acta Otolaryngol. 532 (Suppl.), 46–53] is determined by factors other than head size.
Characterization of optical traps using on-line estimation methods

System identification methods are presented for the estimation of the characteristic frequency of an optically trapped particle. These methods are more amenable to automated on-line measurements and are believed to be less prone to erroneous results compared to techniques based on thermal noise analysis. Optical tweezers have been shown to be an effective tool in measuring the complex interactions of micro-scale particles with piconewton resolution. However, the accuracy of the measurements depends heavily on knowledge of the trap stiffness and the viscous drag coefficient for the trapped particle. The most commonly referenced approach to measuring the trap stiffness is the power spectrum method, which provides the characteristic frequency for the trap based on the roll-off of the frequency response of a trapped particle excited by thermal fluctuations. However, the reliance on thermal fluctuations to excite the trapping dynamics results in a large degree of uncertainty in the estimated characteristic frequency. These issues are addressed by two parameter estimation methods which can be implemented on-line for fast trap characterization. The first is a frequency domain system identification approach which combines swept-sine frequency testing with a least-squares transfer function fitting algorithm. The second is a recursive least-squares parameter estimation scheme. The algorithms and results from simulation studies are discussed in detail.
A Note on the Torque on a Current Loop of Arbitrary Shape Placed in a Uniform Magnetic Field

A simple derivation is given for the torque on a current loop of arbitrary shape, not necessarily planar, when it is placed in a uniform magnetic field.
Methane oxidation and methane fluxes in the ocean surface layer and deep anoxic waters

Measured biological oxidation rates of methane in near-surface waters of the Cariaco Basin are compared with the diffusional fluxes computed from concentration gradients of methane in the surface layer. Methane fluxes and oxidation rates were investigated in surface waters, at the oxic/anoxic interface, and in deep anoxic waters. It is shown that the surface-waters oxidation of methane is a mechanism which modulates the flux of methane from marine waters to the atmosphere.
Fluoroquinolones as chemotherapeutics against mycobacterial infections

The antimicrobial agents used in the treatment of mycobacterial infections have remained largely unchanged for several decades. Primary treatment of tuberculosis relies on four drugs, isoniazid, a rifamycin, pyrazinamide, and ethambutol (or streptomycin), and generally results in >95% cure in uncomplicated tuberculosis infection. Drug resistance greatly complicates treatment of this disease. Treatment of tuberculosis caused by multiply drug-resistant strains with "second-line" drugs remains complex, and is generally tailored to the individual patient and strain. Several of the fluoroquinolones have shown promise as second line drugs for treatment of active disease and, in combination with clarithromycin or azithromycin, ethambutol, and other agents, for treatment of Mycobacterium avium complex infection. While large clinical trials are not possible with second line drugs, clinical treatment data are available and suggest that the quinolones have various degrees of promise in treatment of these infections. Bacterial type II DNA topoisomerases, DNA gyrase and topoisomerase IV, are the targets of quinolones, and provide the genetic basis for quinolone activity in mycobacteria. Mutations in these enzymes results in resistance, and characterization of resistant mutants allows correlation of genotype with susceptibility phenotype. Structure-activity relationship studies have provided further insight into optimal use of quinolones in mycobacterial infections. Care should be taken in treating pneumonia with fluoroquinolones if there is a degree of suspicion of tuberculosis, since quinolone monotherapy may rapidly select for quinolone resistance, thereby removing that class of antibiotic from the small range of treatment options.
Refining the temporal definition of an association at the neuronal level using long-term potentiation and long-term depression in the dentate gyrus

This study sharpens the temporal definition of an association in the context of long-term synaptic modification of the monosynaptic projections from entorhinal cortex to dentate gyrus in the anesthetized rat. The ipsilateral projection produces a powerful postsynaptic excitation and shows synaptic potentiation following 7.5 ms trains. On the other hand, brief, high-frequency contralateral stimulation just after this powerful postsynaptic excitation is followed by long-term depression (LTD) at the synapses of this pathway. Therefore, based on the differential induction of long-term potentiation (LTP) or LTD, a cell can distinguish associated pre- and postsynaptic activation at a temporal resolution at least as small as 7.5 ms.
Varying Assay Geometry to Emulate Connective Tissue Planes in an In Vitro Model of Acupuncture Needling

During traditional acupuncture, fine needles are inserted subcutaneously and rotated, which causes loose fascial tissue to wind around the needle. This coupling is stronger at acupuncture points, which tend to fall above intermuscular fascial planes, than control points, which lay above skeletal muscle. These different anatomical constraints may affect the mechanical coupling. Fascia at acupuncture points is bounded on two sides by skeletal muscle, but at control points is essentially unbounded. These differences were approximated in simple in vitro models. To emulate the narrower boundary within the intermuscular plane, type I collagen was cast in circular gels of different radii. To model the channel-like nature of these planes, collagen was cast in elliptical gels with major and minor axes matching the large and small circular gels, respectively, and in planar gels constrained on two sides. Acupuncture needles were inserted into the gels and rotated via a computer-controlled motor while capturing the evolution of fiber alignment under cross-polarization. Small circular gels aligned faster, but failed earlier than large circular gels. Rotation in elliptical and planar gels generated more alignment-per-revolution than circular gels. Planar gels were particularly resistant to failure. Fiber alignment in circular gels was isotropic, but was stronger in the direction of the minor axis in elliptical and planar gels. In fibroblast-populated gels, cells followed the alignment of the collagen fibers, and also became denser in regions of stronger alignment. These results suggest that the anatomy at acupuncture points provides unique boundaries that accentuate the mechanical response to needle manipulation.
Histochemical Examinations of Chymotrypsin-like Esterases

IN 1953 Gomori1 discovered a tissue enzyme which hydrolysed chloracetoxy naphthoic acid anilide. Mast cells were found to have a large amount of this enzyme activity. Based on the demonstration that the time required to achieve a given colour intensity in an enzymatic histochemical system is inversely proportional to enzyme activity2, it was estimated that mast cells had 30 times the activity of liver and five times the activity of neutrophiles. Later, Benditt and Arase3 were able to show that the enzyme in mast cells strikingly resembled bovine α-chymotrypsin. The present work has carried the resemblance further and examined the distribution of the enzyme in the rat, utilizing a newly synthesized series of esters of naphthoic acid anilide (‘Napthol AS’).
Words on the Web: Noninvasive Detection of Emotional Contagion in Online Social Networks

Does semantic expression spread online from person to person? And if so, what kinds of expression are most likely to spread? To address these questions, we developed a nonexperimental, noninvasive method to detect and quantify contagion of semantic expression in massive online social networks, which we review and discuss here. Using only observational data, the method avoids performing emotional experiments on users of online social networks, a research practice that recently became an object of criticism and concern. Our model combines geographic aggregation and instrumental variables regression to measure the effect of an exogenous variable on an individual's expression and the influence of this change on the expression of others to whom that individual is socially connected. In a previous work, we applied our method to the emotional content of posts generated by a large sample of users over a period of three years. Those results suggest that each post expressing a positive or negative emotion can cause friends to generate one to two additional posts expressing the same emotion, and it also inhibits their use of the opposite emotion. Here, we generalize our method so it can be applied to contexts different than emotional expression and to different forms of content generated by the users of online platforms. The method allows us to determine the usage of words in the same semantic category spread, and to estimate a signed relationship between different semantic categories, showing that an increase in the usage of one category alters the usage of another category in one's social contacts. Finally, it also allows us to estimate the total cumulative effect that a person has on all of her social contacts.
Corrections to Nuclear Energies and Radii in Finite Oscillator Spaces

We derive corrections to the ground-state energies and radii of atomic nuclei that result from the limitations of finite oscillator spaces.
Optimal tariffs and retaliation with perfect foresight

The naive Cournot and Stackelberg retaliation assumptions were replaced with perfect foresight on the part of all countries involved. Each country maximized some measure of welfare subject to a belief about how the other countries would react to changes in tariffs. The two country, two good world was modelled in partial equilibrium, using consumer and producer surplus as approximations to welfare. The problem was solved within the framework of an infinite horizon dynamic programming model. The five equilibrium points representing perfect foresight were classified into three categories: no retaliation, full retaliation, and opposite retaliation. The optimal tariff levels and resulting welfare were compared for various values of the social discount factor;The perfect foresight problem was also solved for M exporting and N importing countries. The levels of the five possible optimal tariffs were examined as the number of exporters and importers was increased. In most cases, the optimal tariffs were subsidies that rapidly declined to zero (free trade) as the number of countries was increased.
The destruction of tori in volume-preserving maps

Abstract Invariant tori are prominent features of symplectic and volume-preserving maps. From the point of view of chaotic transport the most relevant tori are those that are barriers, and thus have codimension one. For an n -dimensional volume-preserving map, such tori are prevalent when the map is nearly “integrable,” in the sense of having one action and n − 1 angle variables. As the map is perturbed, numerical studies show that the originally connected image of the frequency map acquires gaps due to resonances and domains of nonconvergence due to chaos. We present examples of a three-dimensional, generalized standard map for which there is a critical perturbation size, e c , above which there are no tori. Numerical investigations to find the “last invariant torus” reveal some similarities to the behavior found by Greene near a critical invariant circle for area preserving maps: the crossing time through the newly destroyed torus appears to have a power law singularity at e c , and the local phase space near the critical torus contains many high-order resonances.
Approximation methods for control of structural acoustics models with piezoceramic actuators

The active control of acoustic pressure in a 2-D cavity with a flexible boundary (a beam) is considered. Specifically, this control is implemented via piezoceramic patches on the beam which produces pure bending moments. The incorporation of the feedback control in this manner leads to a system with an unbounded input term. Approximation methods in this manner leads to a system with an unbounded input term. Approximation methods in this manner leads to a system with an unbounded input team. Approximation methods in the context of linear quadratic regulator (LQR) state space control formulation are discussed and numerical results demonstrating the effectiveness of this approach in computing feedback controls for noise reduction are presented.
Unexpected expression of intermediate filament protein genes in human oligodendroglioma cell lines.

From a human oligodendroglioma cell line cDNA library, ten intermediate filament (IF) cDNA clones were isolated. Five clones corresponded to vimentin mRNA, two corresponded to cytokeratin K7 mRNA, and two corresponded to cytokeratin K8 mRNA. One clone encoded a novel IF mRNA. The expression of these and other IF protein genes was examined in five cell lines derived from human oligodendroglioma, astrocytoma and neuroblastoma tumors. Vimentin mRNA and K18 mRNA were expressed in all the cell lines. The K7 and K8 genes were expressed only in the oligodendroglioma cell lines. Surprisingly, nestin mRNA was expressed in the astrocytoma lines and the neuroblastoma line, but was not expressed in the oligodendroglioma lines. These results indicate that oligodendroglioma cell lines express Types I and II cytokeratin genes. This pattern of IF gene expression was different from that of the astrocytoma and neuroblastoma cell lines, which expressed IF genes usually associated with the mature cell types or with differentiating fetal neural precursor cells, i.e. GFAP and neurofilament-L. The results also suggest that the oligodendroglioma cell lines are more epithelial in character and do not reflect the gene expression of mature oligodendrocytes.
X-ray nanoscale profiling of layer-by-layer assembled metal/organophosphonate films.

The nanoscale structure of multilayer metal/phosphonate thin films prepared via a layer-by-layer assembly process was studied using specular X-ray reflectivity (XRR), X-ray fluorescence (XRF), and long-period X-ray standing wave (XSW) analysis. After the SiO2 X-ray mirror surfaces were functionalized with a monolayer film terminated with phosphonate groups, the organic multilayer films were assembled by alternating immersions in (a) aqueous solutions containing Zr4+, Hf4+, or Y3+ cations and then (b) organic solvent solutions of PO3−R−PO3, where R was a porphyrin or porphyrin-square spacer molecule. The different heavy metal cations provided X-ray fluorescence marker layers at different heights within the different multilayer assemblies. The XSW measurements used a 22 nm period Si/Mo multilayer mirror. The long-period XSW generated by the zeroth-order (total external reflection) through fourth-order Bragg diffraction conditions made it possible to examine the Fourier transforms of the fluorescent atom dis...
Pitfalls in Diagnosis of Pandemic (Novel) A/H1N1 2009 Influenza

Laboratory diagnosis of influenza is important for treatment, surveillance, infection control, chemoprophylaxis, and monitoring of resistance. Rapid and sensitive nucleic acid amplification tests have widely replaced virus isolation as the reference standard ([9][1]). However, despite improvements
An Analysis of Log Periodic Antenna with Printed Dipoles

An analysis of Log Periodic Antenna with Printed Dioples is presented here. In this analysis, the wave equation for Hertz potential is solved in Cartesian coordinates applying the boundary conditions of a flat strip diople. Using this model, the input currents to the antenna elements, the current distribution of the antenna elements, and the radiation pattern are computed. The computed results are compared with experimental results.
Communicating through Probabilities: Does Quantum Theory Optimize the Transfer of Information?

A quantum measurement can be regarded as a communication channel, in which the parameters of the state are expressed only in the probabilities of the outcomes of the measurement. We begin this paper by considering, in a non-quantum-mechanical setting, the problem of communicating through probabilities. For example, a sender, Alice, wants to convey to a receiver, Bob, the value of a continuous variable, θ, but her only means of conveying this value is by sending Bob a coin in which the value of θ is encoded in the probability of heads. We ask what the optimal encoding is when Bob will be allowed to flip the coin only a finite number of times. As the number of tosses goes to infinity, we find that the optimal encoding is the same as what nature would do if we lived in a world governed by real-vector-space quantum theory. We then ask whether the problem might be modified, so that the optimal communication strategy would be consistent with standard, complex-vector-space quantum theory.
Initiated chemical vapor deposition of polyvinylpyrrolidone-based thin films

Initiated chemical vapor deposition (iCVD) is used for the first time to deposit a non-acrylic carbon-based polymer, polyvinylpyrrolidone (PVP). PVP is known for its hydrophilicity and biocompatibility, and its thin films have found many applications in the biomedical community, one of which is as antibiofouling surfaces. From vapors of 1-vinyl-2-pyrrolidone (VP) and tert-butyl peroxide (TBPO), iCVD produces PVP thin films that are spectroscopically identical to bulk PVP without using any solvents. iCVD works by selectively fragmenting gaseous TBPO with heat to create radicals for initiation of polymerization. This selectivity ensures that the monomer VP does not disintegrate to form species that do not conform to the structure of PVP. Fourier-transform infrared (FTIR), nuclear magnetic resonance, and X-ray photoelectron spectroscopy (XPS) show full retention of the hydrophilic pyrrolidone functional group. Number-average molecular weights range between 6570 and 10,200 g/mol. The addition of ethylene glycol diacrylate (EGDA) vapor to the reaction mixture creates a cross-linked copolymer between VP and EGDA. Films with different degrees of cross-linking can be made depending on the partial pressures of the species. Methods for quantifying the relative incorporation of VP and EGDA using FTIR and XPS are introduced. The film with the lowest degree of cross-linking has a wetting angle of 11°, affirming its high hydrophilicity and iCVD's ability to retain functionality.
DISCOVERING THE POSITRON (II)

THIS remark is often repeated in textbooks and manuals on modem physics. It is singled out here for several reasons: (i) Its innocent, matter-of-fact tone conceals one of the most intricate and interesting chapters in the history of scientific discovery; (2) it encourages an analogy between discoveries within microphysics, and quite noncomparable discoveries within, e.g., natural history; and (3) the actual discovery of the positron, in all its dimensions, constitutes an instructive example of the interplay of theory and experiment within physical science, one of the best a historian, or logician, of science could ever hope for. The positron packet can be dipped into in three different ways. The physicist reaches into this complex of concepts to facilitate his thinking within e.g. quantum field theory, or the experimental study of cosmic rays. The historian of physics attends to the exciting interplay of ideas within the microphysics of the 1920s--the better to perceive the initial resistance to the positron-idea, as well as to trace the theoretical evolution which resulted in the claim that positive electrons exist. The logician will focus upon the internal structure of the arguments and concepts actually employed, and still being employed, by those physicists who have played major roles in this story. In the history of science the positron discovery constitutes at once one of the richest, and yet one of the most neglected, areas of inquiry. The discovery of the positive electron was a discovery of three different particles. I choose to put the matter this way, rather than to
Magnetic resonance imaging signal change patterns and prognosis for myelopathy.

COMMENTARY ON: Avadhani A, Rajasekaran S, Shetty AP. Comparison of prognostic value of different MRI classifications of signal intensity change in cervical spondylotic myelopathy. Spine J 2010;10:475–85 (in this issue) .
A simple method for obtaining melting points of compounds reacting with moisture or oxygen

The melting point capillary is filled and closed in a dry-box and hereafter packed and fused shut outside the box.
Proteinuria in the elderly: evaluation and management

While aging is accompanied by many age-related changes in renal physiology and function, proteinuria should not be considered to be a part of "normal aging". There are many age-prevalent illnesses that predispose one to developing proteinuria and early recognition, and treatment may help retard disease progression or offer an early cure. The presence of proteinuria warrants further evaluation and follow-up if one has any hope of avoiding its progression and delaying the initiation of treatment. This review article will discuss the anatomy and physiology of the aging kidney, the pathophysiology and etiology of proteinuria during later life, methods to evaluate proteinuria, and ways to monitor and manage this problem.
Leptin receptor antagonist treatment ameliorates the effects of long-term maternal hypoxia on adrenal expression of key steroidogenic genes in the ovine fetus

We previously reported elevated adipose leptin expression, plasma leptin concentrations, and adrenocortical leptin receptor expression in the long-term hypoxic (LTH) ovine fetus. This study address...
Effect of Cyclic Predeformation on the Uniaxial Tensile Deformation Behavior of (017) Cu Single Crystals Oriented for Critical Double Slip

The effect of cyclic predeformation at different plastic strain amplitudes γpl on the uniaxial tensile behavior of the [017] critical double-slip-oriented copper single crystal was investigated. A cyclic predeformation at a low γpl of 7.0 × 10−4 was found able to enhance the tensile strength of the [017] crystal at nearly no expense of the decrease in plasticity. However, as the γpl for the prefatigue increases to a higher value of 3.0 × 10−3, the tensile strength of the prefatigued [017] crystal decreases to be slightly less than that of the unfatigued crystal, and simultaneously its tensile plasticity decreases markedly. Therefore, a cyclic predeformation at an appropriate plastic strain amplitude might bring about an obvious strengthening effect for metallic single crystals.
New concepts in vocal fold imaging: a review.

Summary Objective To review new imaging technology potentially useful in the clinical practice of laryngology. Hypothesis Narrow band imaging, iScan (Pentax Medical Company, Montvale, NJ), optical computed tomography, and confocal microscopy have potential value for enhancing diagnosis of laryngeal pathology. Design Literature review. Methods Literature search of computer databases including MEDLINE and PubMed. Results A review of 50 articles suggests that new imaging technologies may enhance clinical diagnostic capabilities. Conclusion The probable value of new imaging technologies suggests that further research is needed to refine these technologies and define their clinical efficacy.
Gaussian beam modes by multipoles with complex source points

It is shown that the complex Hermite-Gaussian wave functions proposed by Siegman can be generated in a straightforward manner by assigning complex locations to the source points in a multipole expansion of an optical field.