cssi/SciSciGPT-SciSciNet huggingface dataset:
Cutaneous microbial biofilm formation as an underlying cause of red scrotum syndrome.

Background Red scrotum syndrome is typically described as well-demarcated erythema of the anterior scrotum accompanied by persistent itching and burning. It is chronic and difficult to treat and contributes to significant psychological distress and reduction in quality of life. The medical literature surrounding the condition is sparse, with the prevalence likely under-recognized and the pathophysiology remaining poorly understood. Formation of a cutaneous microbial biofilm has not been proposed as an underlying etiology. Microbial biofilms can form whenever microorganisms are suspended in fluid on a surface for a prolonged time and are becoming increasingly recognized as important contributors to medical disease (e.g., chronic wounds). Case presentation A 26-year-old man abruptly developed well-demarcated erythema of the bilateral scrotum after vaginal secretions were left covering the scrotum overnight. For 14 months, the patient experienced daily scrotal itching and burning while seeking care from multiple physicians and attempting numerous failed therapies. He eventually obtained complete symptomatic relief with the twice daily application of 0.8% menthol powder. Findings in support of a cutaneous microbial biofilm as the underlying etiology include: (1) the condition began following a typical scenario that would facilitate biofilm formation; (2) the demarcation of erythema precisely follows the scrotal hairline, suggesting that hair follicles acted as scaffolding during biofilm formation; (3) despite resolution of symptoms, the scrotal erythema has persisted, unchanged in boundary 15 years after the condition began; and (4) the erythematous skin demonstrates prolonged retention of gentian violet dye in comparison with adjacent unaffected skin, suggesting the presence of dye-avid material on the skin surface. Conclusion The probability that microorganisms, under proper conditions, can form biofilm on intact skin is poorly recognized. This case presents a compelling argument for a cutaneous microbial biofilm as the underlying cause of red scrotum syndrome in one patient, and a review of similarities with other reported cases suggests the same etiology is likely responsible for a significant portion of the total disease burden. This etiology may also be a significant contributor to the disease burden of vulvodynia, a condition with many similarities to red scrotum syndrome.
Modeling, parameter identification, guidance and control of an unmanned surface vehicle with experimental results

Abstract This work proposes an autopilot scheme for self-steering an Unmanned Surface Vehicle (USV) in terms of heading and speed control, route following and waypoints tracking. The majority of regulators developed in the literature only provide heading control, which is a considerable weakness since the drift effects due to wind and marine currents cause the USV to move away from the planned path. This work deals with this problem and firstly proposes a mathematical model with three degrees of freedom for simulating the USV behavior. Second, USV parameter are calculated experimentally, and then an autopilot system is designed letting the USV to rapidly and smoothly reach a desired path and remain precisely on it. The developed autopilot, which is based on sliding mode control, consists of two levels of regulation, low-level controller for speed and heading control and a high-level controller for generating the desired speed and heading according to two different navigation modes: waypoints tracking and/or path following. Experimental results are carried out to verify the effectiveness of the proposed autopilot in term of heading control for waypoints tracking.
Testing spatial effects and random effects in a nested panel data model

We propose a multilevel spatial econometric model including spatially correlated error, spatially lagged dependent variable, county-level random effects and nested district-level random effects within a county. We construct joint Lagrange multiplier (LM) test to detect both the spatial effects and the random effects, LM tests to detect the spatial error correlation and/or the spatial lag dependence allowing for both types of random effects, and LM tests to detect the county-level random effects and/or the nested district-level random effects allowing for both types of spatial effects. A Monte Carlo simulation is conducted to show their good finite sample performances.
Mesenchymal Stem Cell-Based Therapy in a Mouse Model of Experimental Autoimmune Encephalomyelitis (EAE)

Multiple sclerosis (MS) is a common neurodegenerative disease that presents after an auto-reactive immune response against constituents of the central nervous system. Demyelination, inflammation, and white matter lesions are all hallmarks of this disease. Clinical research supports the use of mesenchymal stem cells (MSCs) as therapy for MS to ameliorate symptoms and pathology. MSCs can be isolated from multiple tissues, including adipose and bone marrow, and are able to migrate to sites of pathology, release anti-inflammatory factors, and provide immunomodulatory and neuroprotective effects once administered. Numerous studies have demonstrated the beneficial effects of MSCs in experimental autoimmune encephalomyelitis (EAE), an induced model of MS. EAE can be induced in several species; however, the mouse is commonly used for therapeutic testing. In the following chapter, scientists will be able to learn how to prepare reagents and MSCs (e.g., isolate, culture, and expand) as well as skillfully execute induction of EAE in mice and administer stem cell-based treatments. Standard methods used to evaluate the disease progression and analyze postmortem tissues are also included.
Apophis: Complex rotation and hazard assessment

We present an updated hazard assessment for near-Earth asteroid (99942) Apophis. The stiff dynamics and the high precision of the trajectory of Apophis call for the most accurate dynamical model. In particular, the dominant source of ephemeris prediction uncertainty is the Yarkovsky effect. We include the Yarkovsky perturbation in the force model by numerically computing the related thermal recoil accelerations. These acceleration are statistically computed according to the known physical properties of Apophis and their uncertainties. Special effort is required to account for the non-principal axis rotation state of Apophis. Finally, we generated Monte Carlo samples to capture the uncertainty in both the orbital elements and the Yarkovsky accelerations and compute the probability of future Earth impacts. Whereas collisions with Earth before 2060 are ruled out, impacts are still possible starting in 2060. The highest impact probability is seven in a million for the April 2068 Earth encounter.
On the Exonuclease Activity of Phage T4 Deoxyribonucleic Acid Polymerase

Abstract In the absence of deoxynucleoside triphosphates, T4 DNA polymerase functions as a 3' → 5' exonuclease. It has a strong preference for single stranded DNA, which is hydrolyzed 100 times faster than double stranded DNA. Polynucleotides of short chain length (300 residues) are hydrolyzed more rapidly than longer chain polymers (3000 residues) of the same base composition and at the same concentration of termini. A likely explanation for this finding is that the enzyme can bind to internal nucleotides as well as to the 3'-hydroxyl terminus of a polynucleotide, thus inhibiting hydrolysis which only occurs at the 3'-hydroxyl end. The products of hydrolysis are deoxynucleoside 5'-monophosphates and a dinucleotide derived from the 5' terminus of the polynucleotide. In contrast to the polymerization reaction which is stimulated by the product of T4 gene 32, the exonuclease activity is completely inhibited. Escherichia coli DNA, glucosylated T4 DNA as well as a variety of synthetic polydeoxynucleotides are susceptible to the enzyme.
Lessons from Lowell, Massachusetts (1821–62): The Shifting Sands of Managerial Beneficence

Far more than a mechanism to voyeuristically delve into the past to satisfy trivial interests, management history can be used to provide insight into contemporary practices and guide us away from repeating past mistakes. Using historiography, this paper offers a glimpse into the nature of the employer–employee relationship, comparing events from the earliest days of industrialization to the present. Set in the historical site of Lowell, Massachusetts, the birthplace of the American Industrial Revolution, this research addresses the progression of events that seem to predictably occur when well-meaning entrepreneurial enterprises face environmental turbulence and subsequently alter their labor philosophy from paternalism to social Darwinism. In the early 1800s, Lowell's textile mills represented a progressive environment. A close-knit, planned community was created which allowed the women opertives to grow socially and intellectually. However, economic downturns resulted in cycles of wage-cutting and cost-saving efforts. Eventually, the women were replaced with immigrants who were willing to tolerate substandard working conditions. By the 1860s, the owners had completely abandoned their concept that corporations should have souls. In history, market forces are continually in flux and often so is management's perception about whether the worker is a valuable asset or an easily discarded econom ic liability. Reactions to this unpredictability are addressed.
Two Decades of Stability and Change in Age at First Union Formation

The landscape of union formation has been shifting; Americans are now marrying at the highest ages on record and the majority of young adults have cohabited. Yet little attention has been paid to the timing of cohabitation relative to marriage. Using the National Survey of Families and Households and 4 cycles of the National Survey of Family Growth, the authors examined the timing of marriage, cohabitation, and unions over 20 years. As the median age at first marriage has climbed, the age at cohabitation has remained stable for men and women. The changes in the timing of union formation have been similar according to race/ethnicity. The marked delay in marriage among women and men with low educational attainment has resulted in a near-convergence in the age at first marriage according to education. The authors conclude that the rise in cohabitation has offset changes in the levels and timing of marriage.
Prevalence and Mental Health Outcomes of Homicide Survivors in a Representative US Sample of Adolescents: Data from the 2005 National Survey of Adolescents.

Background: Each homicide leaves behind several friends and family members, or homicide survivors. However, limited information is available on the impact of homicide on adolescent survivors. The purpose of the current study was to identify the prevalence of homicide survivorship and to determine mental health outcomes within a sample of US adolescent survivors. Methods: A nationally representative sample of American adolescents (N = 3,614) between the ages of 12 and 17 completed structured telephone interviews assessing homicide survivorship and mental health consequences including posttraumatic stress disorder (PTSD), depression, drug use, and alcohol abuse. Results: Reported prevalence within this sample of losing a loved one to criminal homicide was 9%, losing a loved one to vehicular homicide was 7%, and losing a loved one to both types of homicide was 2%. Logistic regression analyses found that adolescents who reported being homicide survivors were significantly more likely to report depression, drug use, and alcohol abuse after controlling for demographic factors and other violence exposure. Conclusions: If the results from this study are generalizable to the US population, roughly 1 in 5 American adolescents may be impacted by homicide. Further, adolescents exposed to such a loss are at increased risk for mental health sequelae. Results suggest that greater attention needs to be paid to address the needs of these often underserved victims. Language: en
Tritrichomonas foetus: pathogenesis of acute infection in normal, estradiol-treated, and stressed mice.

Environmental stress and endocrine control can affect pathogenesis of sexually transmitted diseases such as trichomoniasis. Acute Tritrichomonas foetus infection was compared in female BALB/c mice to infections in mice treated with high doses of estradiol or housed in constant bright illumination (stressed). In untreated mice, T. foetus readily colonized the reproductive tract, causing minimal epithelial damage and inflammation. Several fold increases of IFN-γ, TNF-α, MCP-1, and IL-6 cytokines were detected after estradiol-treatment of mice, resulting in greatly enhanced inflammation and tissue damage throughout the reproductive tract. Interestingly, estradiol-treatment of mice resulted in reduced T. foetus colonization compared to untreated mice. Infection in stressed mice resulted in increased tissue damage, inflammation, and inflammatory cytokine expression, although parasite colonization within the reproductive tract was similar to that in untreated mice. These results indicate that either estradiol-treatment or stress result in pathogenesis often observed during severe disease. Alternatively, infection in non-treated mice results in chronic colonization, with little inflammation or pathology.
Color-octet fraction in J / ψ production and absorption

The cross section between a $c\overline{c}$ pair and a nucleon is small and sensitive to the $c$-$\overline{c}$ separation if the pair is in a color-singlet state, but very large and insensitive to the separation if it is in a color-octet state. We use this property in an absorption model involving both color components to deduce the color structure of $c\overline{c}$ pairs produced in $p\stackrel{\ensuremath{\rightarrow}}{A}\ensuremath{\psi}X$ reactions. Our analysis shows that the NA3, NA38, and E772 data are not inconsistent with the theoretical picture that color-octet and color-singlet precursors are produced in roughly equal proportions if the produced color-singlet precursors are pointlike and transparent. However, if the color-singlet precursors are not transparent but have a cross section of a few mb, these data do show a definite preference for a larger fraction of color-singlet precursors. In either case, the color-octet fraction increases with ${x}_{{}_{F}}$, approaching close to unity as ${x}_{{}_{F}}$ increases to about 0.5.
Infinite-component fields. II. The electromagnetic structure of bosons

New closed forms of the inelastic form factors and structure functions ${W}_{1}(\ensuremath{\nu}, {Q}^{2})$, ${W}_{2}(\ensuremath{\nu}, {Q}^{2})$ as a function of two variables have been obtained in an infinite-multiplet model. The relativistic H atom and a model of the pion are special cases. The nonrelativistic limit in the former case agrees with the result of Massey and Mohr. For the latter case a special situation which leads to scaling is discussed in detail.
Regulation of hypoxia-inducible factor 1α (HIF-1α) by lysophosphatidic acid is dependent on interplay between p53 and Krüppel-like factor 5.

Hypoxia-inducible factor 1α (HIF-1α) and p53 are pivotal regulators of tumor growth. Lysophosphatidic acid (LPA) is a lipid mediator that functions as a mitogen by acting through LPA receptors. We have shown previously that LPA stimulates HIF-1α expression in colon cancer cells. To determine the mechanism of HIF-1α induction by LPA, we compared the effect of LPA on HIF-1α in several colon cancer cell lines. LPA transcriptionally induced HIF-1α in colon cancer cells. HIF-1α induction was observed in cells expressing WT p53, where LPA decreased p53 expression. However, LPA failed to induce HIF-1α when the p53 gene was mutated. A decrease in p53 expression was dependent on induction of p53-specific E3 ubiquitin ligase Mdm2 by LPA. Kruppel-like factor 5 (KLF5) is an effector of LPA-induced proliferation of colon cancer cells. Because HIF-1α was necessary for LPA-induced growth of colon cancer cells, we determined the relationship between KLF5 and HIF-1α by a loss-of-function approach. Silencing of KLF5 inhibited LPA-induced HIF-1α induction, suggesting that KLF5 is an upstream regulator of HIF-1α. KLF5 and p53 binding to the Hif1α promoter was assessed by ChIP assay. LPA increased the occupancy of the Hif1α promoter by KLF5, while decreasing p53 binding. Transfection of HCT116 cells with KLF5 or p53 attenuated the binding of the other transcription factor. These results identify KLF5 as a transactivator of HIF-1α and show that LPA regulates HIF-1α by dynamically modulating its interaction with KLF5 and p53. Background: LPA induces HIF-1α expression, but the underlying mechanism remains unknown. Results: LPA induced HIF-1α by decreasing p53 expression, and additionally, KLF5 transactivated HIF-1α expression. Conclusion: KLF5 and p53 reciprocally regulate HIF-1α expression. Significance: This study provides a new dimension to understanding how LPA promotes colon cancer.
Solidarity and sexual communication as selective filters: A report on intimate relationship development

This study attempts to extend Wheeless, Wheeless and Baus's (1984) examination of variables that distinguish between developing and deteriorating relationships. The purpose of this study is to examine the degree to which interpersonal solidarity and sexual communication satisfaction are related to relationship stages, and reports of satisfaction in intimate relationships. Findings suggest that feelings of solidarity in highly developed intimate relationship stages are more salient than sexual communication satisfaction to reports of overall relationship satisfaction. This study also considers the influence of socially desirable responding on reports of sexual communication satisfaction.
Quanta: a toolkit for high performance data delivery over photonic networks

Quanta is a cross-platform adaptive networking toolkit for supporting the data delivery requirements of interactive and bandwidth intensive applications, such as Amplified Collaboration Environments. One of the unique goals of Quanta is to provide applications with the ability to provision optical pathways (commonly referred to as Lambdas) in dedicated photonic networks. This paper will introduce Quanta's architecture and capabilities, with particular attention given to its aggressive and predictable high performance data transport scheme called Reliable Blast UDP (RBUDP). We provide an analytical model to predict RBUDP's performance and compare the results of our model against experimental results performed over a high speed wide-area network.
IMPROVED MINIMAX ESTIMATOR OF COVARIANCE WHEN ADDITIONAL INFORMATION IS AVAILABLE ON SOME COORDINATES

Let S ∼ Wp (n, Σ), where Σ (p × p) is an unknown positive definite matrix. Let q (<p) be the number of variates on which additional information is available and Yi ∼ Nq (0, Σ11), i = 1, 2,…,m. We obtain minimax estimators of Σ and Σ−1. Monte Carlo simulation indicates that the minimax estimators have smaller risk than the maximum likelihood estimators for p = 2, q = 1 and p = 3, q = 1.
Expression and characterization of Arabidopsis phospholipase Dγ2

The phospholipase D (PLD) family of Arabidopsis thaliana has 12 identified members, including three highly homologous PLDgammas. The enzymatic and molecular properties of PLDgamma2 were characterized and compared with those of PLDgamma1. Two variants of PLDgamma2 cDNAs, designated PLDgamma2a and PLDgamma2b, were isolated, and they differ in the presence of a 96-nucleotide fragment at the beginning of the open reading frame. Catalytically active PLDgamma2a was expressed in E. coli. PLDgamma2a and gamma1 both require phosphatidylinositol 4,5-bisphosphate (PIP(2)) and calcium for activity, but they differ in the effect of PIP(2) and Triton X-100 on their activities. While Triton X-100 could greatly activate PLDgamma1 activity and served only as a neutral diluent in the substrate vesicles, it totally abolished PLDgamma2a activity and prohibited any stimulation effect from PIP(2.) PLDgamma2a misses one of the basic, PIP(2)-interacting residues, which may weaken the binding of PIP(2) to PLDgamma2a. In addition, PLDgamma2 and PLDgamma1 displayed different patterns of expression in different tissues, and the transcript of PLDgamma2a differs from that of PLDgamma1 by having a longer 5'-UTR. These differences in biochemical and molecular properties suggest that the highly homologous PLDgammas are subjected to unique regulations and might have distinguishable functions.
An exact algorithm for resource constrained sequencing with application to production scheduling under an aggregate deadline

Abstract Sequencing problems arise both in isolation and as subproblems in the context of batch process scheduling. In some cases, production sequences are constrained by the availability of resources such as manpower, storage or available processing time. We present a general model for resource-constrained sequencing and show that previously studied sequencing models are a special case. The model is equivalent to a member of the Traveling Salesman Problem (TSP) family, however it is fundamentally more difficult than most well-studied members since even proof of feasibility is an NP-complete problem. We present an exact solution algorithm based on a Lagrangian lower bounding technique, generalized patching heuristic and problem-specific branching rules. To illustrate the versatility of the algorithm, computational results are presented for sequential, parallel and distributed computing implementations for problems containing up to 250 jobs. As an illustration of the practicality of the algorithm we demonstrate the scheduling of a processing facility involving sequences dependent transition costs and an aggregate due date for all job completion times.
Effects of carrier envelope phase on single shot XUV supercontinuum measurements

Polarization gated high harmonic generation was phase matched to produce 104 XUV photons per shot. This allowed us to observe the dependence of the XUV supercontinuum on the carrier envelope phase of the laser pulses.
Experimental Investigation of the Phase Equilibria in the Al-Mn-Zn System at 400°C

Al-Mn-Zn ternary system is experimentally investigated at 400°C using diffusion couples and key alloys. Phase relationships and homogeneity ranges are determined for binary and ternary compounds using EPMA, SEM/EDS, and XRD. Reported ternary compound T3 (Al11Mn3Zn2) is confirmed in this study and is denoted as τ2 in this paper. Two new ternary compounds (τ1 and τ3) are observed in this system at 400°C. τ1 is determined as a stoichiometric compound with the composition of Al31Mn8Zn11. τ3 has been found to have homogeneity range of AlxMnyZnz ( at%; at%; at%). The binary compounds Al4Mn and Al11Mn4 exhibit limited solid solubility of around 6 at% and 4 at% Zn, respectively. Terminal solid solution Al8Mn5 is found to have maximum ternary solubility of about 10 at% Zn. In addition, ternary solubility of Al-rich β-Mn′ at 400°C is determined as 4 at% Zn. Zn-rich β-Mn′′ has a ternary solubility of 3 at% Al. The solubility of Al in Mn5Zn21 is measured as 5 at%. Based on the current experimental results, the isothermal section of Al-Mn-Zn ternary system at 400°C has been constructed.
Cardiac electrophysiologic effects of fentanyl and combinations of fentanyl and neuromuscular relaxants in pentobarbital-anesthetized dogs

The effects of fentanyl, both alone and in combination with pancuronium bromide or succinylcholine, on atrioventricular (AV) node and ventricular conduction times and refractory periods were studied. Twenty-four pentobarbital-anesthetized dogs were instrumented both with an intraaortic catheter to measure cardiac conduction times and, through a thoracotomy, with atrial and ventricular epicardial pacing electrodes to provide premature stimulation that would allow measurement of atrial and ventricular refractoriness. Fentanyl prolonged the RR interval in both low- (100 micrograms/kg) and high-dose (400 micrograms/kg) groups by 26 and 45%, respectively, and prolonged AV node conduction time by 28 and 25%, respectively. During atrial pacing at a rate sufficient to capture the atria, AV node conduction time lengthened in the low- and high-dose groups by 27 and 25%, respectively. Fentanyl also significantly lengthened AV node effective and functional refractory periods and ventricular effective refractory periods in both groups. Pancuronium (0.1 mg/kg) administered after fentanyl shortened RR intervals in the low- and high-dose groups by 14 and 22%, respectively, and shortened AV conduction times by 18 and 20%, respectively, but did not restore all values to baseline. Pancuronium significantly shortened AV node refractory periods in the low-dose but not the high-dose group. When administered after fentanyl, succinylcholine (2 mg/kg) significantly shortened the RR interval in the low- and high-dose groups by 14 and 12%, respectively. Succinylcholine shortened AV node conduction slightly but without significance and had no effect on cardiac refractoriness. His-Purkinje conduction remained unaffected by any drug intervention. These data demonstrate that fentanyl depresses cardiac conduction; subsequent administration of pancuronium and succinylcholine partially reverses this effect.
Effect of interatomic potential on the calculated energy and structure of high-angle coincident site grain boundaries—II. (100) Twist boundaries in Cu, Ag and Au

Abstract A new computer code is described which permits the investigation of the energy and structure of coincident-site lattice (CSL) grain boundaries in metals. As an improvement over computer programs used by other workers, the full second-derivative (force-constant) matrix associated with a given interatomic potential is applied for the iterative energy minimization. Using this extremely efficient and reliable relaxation procedure the effect of the form of the interatomic potential and its truncation radius on the predicted grain-boundary energy and structure is investigated. Six different potentials for aluminum, ranging from a Morse potential to a pseudopotential, are applied to the simulation of the energy and structure of (100) CSL twist boundaries with values of ∑, the inverse density of CSL sites, ranging between ∑ = 5 and ∑ = 73. It is found that not only do both the energy and structure of a given boundary vary greatly from one potential to another, but also that the relative energies of different boundaries, i.e. the boundary-energy vs misfit-angle curves, depend on the potential. In contrast to recent claims of Brokman and Balluffi, no “cusps” in these curves are found for potentials which ignore the charge-density oscillations. The two basic assumptions of the Brokman-Balluffi cusp model are found to be valid only for extremely simple potentials with very short cutoff radii. It is suggested that (i) charge-density oscillations may be important for predicting grain-boundary properties, and (ii) no obvious relationship exists between the grain-boundary geometry (∑) and the energy.
DEVELOPMENT OF THE SMALL BUSINESS INVESTMENT COMPANY PROGRAM

THIS DISSERTATION IS a survey of the provisions for small business investment companies and their operations from January 1, 1959, to September 30, 1960. The formation of small business investment companies was provided for by the Small Business Investment Act of 1958, which the federal government enacted in response to a growing interest in the financial problems of small business concerns. The act was to supplement, rather than to supplant, the flow of private capital to the small business segment of the nation. To carry out the objectives of the act, the Small Business Administration was assigned the task of licensing and regulating small business investment companies, and Congress appropriated $250 million to the Administration to be used for relending to the investment companies during the first 2-2 years of the program. The agency was authorized under the act to purchase subordinated debentures from and to make long-term loans to small business investment companies, which in turn would provide equity capital and long-term credit to small business concerns. During the first nine months of 1960, nine amendments to "Small Business Administration Rules and Regulations" governing the operation of the small business investment companies were made which have resulted in an improved program. One of the changes permits the companies to invest in the equity securities of small business concerns in the form of (1) certificates of stock of any class and (2) debt instruments which contain conversion features, stock-purchase warrants, or options to buy equity securities. By the end of 1959, sixty-one small business investment companies had been licensed, and nine months later the number had increased to 136. During the latter half of 1960, the proposals to form new licensees averaged about twenty-five per month. This increase in the flow of initial capital to small business investment companies was accompanied by numerous successful public issues of stock by them. Ascending public acceptance of the stock was probably influenced by
A simple controlled method for the clinical evaluation of antidiarrheal drugs

A castor oil model of induced diarrhea was used to evaluate dose regimens of the standard antidiarrheal polycarbophil. The study population consisted of 100 healthy volunteers, divided into five groups of 20 each, in whom diarrhea was induced by 120 ml flavored 36.4% castor oil. The polycarbophil dose regimens evaluated were 1, 1.5, 2, or 3 gm at 30-min intervals after castor oil to total the usual prescribed dose of 6 gm/day. One gram taken every 30 min for six doses lowered the number of bowel movements and also induced the least number of cramps and lowest cramp severity rating (reported by subjects). The same total dose over a different dosing interval was no more effective than placebo. Clinical Pharmacology and Therapeutics (1982) 31, 766–769; doi:10.1038/clpt.1982.108
Heat Treatments as a Method of Protection for a Ceramic Fiber—Glass Matrix Composite

Thermal exposure in air has been shown to embrittle a ceramic fiber-glass matrix composite by the infiltration of oxygen to the fiber-matrix interface. Samples exposed at sufficiently high temperatures demonstrate less embrittlement and less strength loss than samples exposed at intermediate temperatures, because of a material flow which seals the surface. It is shown that the protection against embrittlement provided by a short, high-temperature thermal treatment remains in force for materials subsequently exposed to intermediate temperatures under both loaded and unloaded conditions.
Interrelationships between fluid, electrolyte and acid‐base balance during maximal exercise

Summary Exercise at maximal intensity results in marked, but transient alterations in plasma electrolyte concentration and acid-base balance. Compartmental fluid shifts contribute to the increased haematocrit, plasma protein and electrolyte concentrations. Elevations in plasma sodium and potassium concentrations relative to chloride tend to ameliorate the impact of lactate accumulation on anion-cation balance. Lactate accumulation is associated with the development of a profound metabolic acidosis, but there are physiologically important differences between the mixed venous and arterial acid-base values. Arterial blood is characterised by a moderate hypoxaemia, marked acidosis, modest increase in the partial pressure of carbon dioxide (PCO2) and a marked decrease in bicarbonate. Mixed venous blood pH is lower than arterial and is associated with a profound increase in PCO2 with a slight increase in bicarbonate. It is estimated that over 70% of the CO2 produced during maximal exercise is transported as bicarbonate in the venous circulation. This is largely a function of the carbonic anhydrase-dependent chloride shift in which erythrocytes participate in CO2 transport from the tissues to the lungs. The chloride shift is responsible for the mixed venous-arterial differences in plasma chloride concentration. The compartmental fluid shifts as well as the alterations in plasma electrolyte concentration and acid-base balance are part of the integrated physiological response to the energy generating metabolic events associated with maximal exercise.
The perceptual balance of color

The cone contrasts carrying different dimensions of color vision vary greatly in magnitude, yet the perceived contrast of color and luminance in the world appears similar. We examined how this perceptual balance is adjusted by adaptation to the contrast in images. Observers set the level of L vs. M and S vs. LM contrast in 1/f noise images to match the perceived strength of a fixed level of luminance contrast. The perceptual balance of color in the images was roughly consistent with the range of contrast characteristic of natural images. Relative perceived contrast could be strongly biased by brief prior exposure to images with lower or higher levels of chromatic contrast. Similar adaptation effects were found for luminance contrast in images of natural scenes. For both, observers reliably chose the contrast balance that appeared correct, and these choices were rapidly recalibrated by adaptation. This recalibration of the norm for contrast could reflect both changes in sensitivity and shifts in criterion. Our results are consistent with the possibility that color mechanisms adjust the range of their responses to match the range of signals in the environment, and that contrast adaptation plays an important role in these adjustments.
Private pension funds in Argentina's new integrated pension system

Argentina implemented a major reform of its pension system in 1994. The new system has a mixed public-and-private two-pillar structure. Its main elements are an unfunded, defined benefit pillar operated by the state and paying a basic pension to all workers who meet the minimum eligibility period, and a fully funded defined-contribution individual capitalization pillar managed by specially authorized companies (AFJPs). The second pillar also has a public defined-benefit component, which is operated on an unfunded basis. The new system replaced the old public pay-as-you-go pension system, which was facing immense financial pressures. The author assesses the performance of the funded component of the second pillar. He finds that: 1) The private pillar had attracted (by June, 1996) 67 percent of all workers participating in the new integrated system. It also represents 60 percent of those who are active contributors. It has attracted many younger workers and has begun to mobilize a large, fast, growing pool of long-term financial resources. 2) The AFJPs have earned very high real investment returns, offset by very high operating costs. Individual affiliates have so far earned negative real returns because of high commission charges. But in the long run, net returns are likely to be positive as assets accumulate and operating costs are better controlled. 3) Effective coverage is quite low. Affiliates represent fewer than 60 percent of eligible workers and only about 40 percent of the labor force. Fewer than 30 percent of eligible workers and only about 20 percent of the labor force actively contribute. 4) Because the new system is young, the number of beneficiaries is small, mostly recipients of survivorship and disability pensions. 5) Market concentration is high, although lower than in Chile. The top three companies account for 47 percent of affiliates and assets; the top six account for 78 percent. 6) In March, 1997, asset allocation was 51 percent government bonds, 23 percent corporate inquiries and mutual fund shares, 17 percent bank deposits, and 7 percent corporate bonds. Equity holdings share has been rising, mainly at the expense of bank deposits. 7) Real rates of return average over 15 percent a year, although high commission charges substantially reduce the net real returns to individual workers. But costs are coming down sharply as a percentage of average assets. Net real returns for a worker's full career are expected to be highly positive so long as gross investment returns remain strong. The AFJP system faces three main challenges: how to contain operating and marketing costs; how to increase effective coverage; and how to relax the draconian regulations while maintaining a stable, transparent, and safe system.
Synthesis of (4-[18F]fluorophenyl)triphenylphosphonium as a potential imaging agent for mitochondrial dysfunction

Tetraphenylphosphonium (TPP) cation is able to function as a molecular probe for monitoring mitochondrial disease. The F-18 labeled TPP, (4-[18F]fluorophenyl) triphenylphosphonium (18FTPP), was therefore developed as a PET radioligand for in vivo molecular imaging of mitochondrial dysfunction. 18FTPP was synthesized via direct nucleophilic substitution of no-carrier-added [18F]fluoride with the precursor 4-nitrophenyltriphenylphosphonium. After purification by HPLC, the average radiochemical yield was determined to be 10–15% and the specific activity was >500 Ci/mmol at the end of synthesis. The total synthesis time was within 60 min, and the radiochemical purity of the 18FTPP was above 95%. Copyright © 2005 John Wiley & Sons, Ltd.
A Study of the Effect of a “Resting Splint” on Peak Grip Strength:

The purpose of this research was to study the effect of a resting wrist splint on the change in peak power grip strength (PGS) as compared with bare handed PGS, and to investigate the role of hand morphology on the results. Ninety-six subjects were tested for (PGS) with a Jamar Dynamometer under two conditions: with and without a resting splint. The results showed that PGS decreased by an average of 13.71 % (1.35 SE) while subjects wore the wrist splint as compared with the bare handed PGS. A paired t-test was performed on this difference and found to be significant (p<.0005). Female subjects (N = 44) experienced a two-fold greater percent decrease in their PGS (18.52%, 1.49 SE) than male subjects (9.97%, 1.96 SE). The results of this study suggest that PGS is attenuated with the use of a wrist splint, however none of the anthropometric measurements taken of the hand and wrist proved to be correlated with the dependant variables, change and & percent change in PGS. Correlational analysis found that the in...
Afrikaner identity and the music of Johannes Kerkorrel

As old identity verities are dislodged, post-apartheid South Africa is witness to dramatic identitary flux. This study examines Afrikaner identity and particularly that of the generational cohort who witnessed the end of apartheid as young adults. Employing a hermeneutic semiology, the study provides a reading of Johannes Kerkorrel's music, arguing that, as cultural text, it enacts identitary discourse and tension. As such, several identitary moments and motifs are noted across a period of roughly 20 years, including that of identity as rebellion, location and individualising interiority. Finally, it is suggested that the law-of-the-father, as apartheid bequest, organises and animates identity struggles for this generation.
Real time in vitro measurement of oxygen uptake rates for HEPG2 liver cells encapsulated in alginate matrices

Quantitative non-invasive measurement of critical physiological parameters is necessary to assess the functionality and applicability of tissue engineered matrices. Advancements in fiber optic sensors have made it possible for measuring parameters such as oxygen, glucose, and aminoacids necessary for viable tissue growth. In this study, we have devised an experimental protocol to measure in real time, the oxygen uptake rate (OUR) values for a selected liver cell line (HEPG2) when grown (a) on cover glass slides, and (b) encapsulated within alginate based hydrogel matrices. For both cases, the oxygen uptake rates of HEPG2 cells at selected time points varied in close co-relation with cell proliferation and metabolic activity during the 7-day culture period. This investigation concludes that OUR can be used as an indicative parameter to assess the metabolic activity of cells encapsulated within a matrix. The study also presents a fiber optic sensing technology as a non-invasive diagnostic tool to monitor cell behavior and activity.
CORRELATING OFF-AXIS TENSION TESTS TO SHEAR MODULUS OF WOOD-BASED PANELS

The weakness of existing relationships correlating off-axis modulus of elasticity \iE\dθ to shear modulus \iG\D12\N for wood composite panels is demonstrated through presentation of extensive experimental data. A new relationship is proposed that performs better than existing equations found in the literature. This relationship can be manipulated to calculate the shear modulus \iG\D12\N of orthotropic specimens such as wood-based panels solely from off-axis tension (or compression) tests. The proposed relationship reduces to classical theory for the isotropic case. In all cases tested, the newly proposed relationship is a better fit to the data than the traditional orthotropic elasticity equation.
Dichromate as a stain for MR microscopy

High resolution MR microscopy is normally performed at high field (≥7T) due to the increased MR signal available. At lower fields, for example, 4.7T, one way to acquire more signal is to decrease T 1 relaxation times and acquire more signal per unit time. Non-specific contrast agents may be used to shorten T 1 but contrast between tissues may remain sub-optimal. In this study, the use of diamagnetic dichromate ions as a stain for MR microscopy has been investigated. Heterogeneous tissue oxidation by dichromate creates paramagnetic chromium species that both shorten T 1 and enhance tissue contrast. This study demonstrates that increased SNR and excellent tissue contrast may be achieved by soaking fixed and freshly excised tissue in aqueous dichromate solution.
Density, thermal expansivity, viscosity and refractive index of lysozyme solutions at crystal growth concentrations

Abstract Lysozyme has been widely used as a model system for nucleation and crystal growth studies of globular proteins. Yet, few of the properties of lysozyme solutions, which are needed for interpreting the results of such studies, are known. We have investigated the dependence of the density, thermal expansivity, viscosity and refractive index of lysozyme solutions on protein concentration and temperature at various pH values and sodium chloride concentrations. Extensive data are presented in the form of tables and equations. In particular, we found that the solution volumes varied as T 3 2 . This behavior, which appears to be characteristic for a large class of liquids, suggests that thermal expansion is dominantly due to translational motion.
Conditional Dependence in Precious Metal Prices

This study investigates the time-series properties of gold and silver spot prices. Both precious metal price series are found to exhibit time dependence and pronounced generalized autoregressive conditional heteroscedastic (GARCH) effects. Splitting the data into similar economic subperiods provides superior explanation of these effects because of the observed long-run nonconstancy of the unconditional variance. Further, the power exponential distribution, as opposed to the Student-t, is found to portray accurately the thick-tailed conditional variance that remains after the GARCH effects are removed. These findings imply that constant variance pricing models are inappropriate for securities that are based on precious metal prices.
New species of Araceae from Venezuela and the Guianas

Abstract Croat T. B., Outman R. & Kostelac C. V.: New species of Araceae from Venezuela and the Guianas. — Willdenowia 40: 137–146. — Online ISSN 1868-6397; © 2010 BGBM Berlin-Dahlem. doi:10.3372/wi.40.40107 (available via http://dx.doi.org/) Six species are described as new to science from NE South America: Anthurium cremersii, Philodendron grenandii and P. jonkerorum from the Guianas, A. huberi and A. uasadiense from the Guiana Highlands in Venezuela and A. merlei from the coastal range of NE Venezuela.
Continuing the Conversation: A Response to Smith:

I n the article to which Erick Smith responds, I suggested that the emergence of constructivism and sociocultural theory constitute two of the major trends in mathematics education during the past decade. My overall goal was to question the claims that adherents to each of these perspectives sometimes make for the hegemony of their own views. I instead outlined a more pragmatic approach in which we account for learning as it occurs in social and cultural context by bringing one perspective or the other to the fore as the need arises. Our activity as researchers is then seen to be situated in that justifications for one perspective or the other would be made with respect to the problems and issues at hand. Smith accepts these general suggestions and proposes a refinement of the theoretical tools or constructs that might contribute to a pragmatic approach of this type. I concur with several of his observations and agree that we need to use language that assists us in maintaining distinctions between perspectives. In addition, he is correct in observing that I did not specifically address various uses of the term knowledge, but instead limited my focus to meaning and context. In this response, I first comment on Smith's proposed knowing/knowledge distinction and then clarify a possible ambiguity in my use of the term constructivism in the original article. In doing so, I distinguish between Piagetian-based psychological constructivism as outlined by Smith and the version of constructivism I discussed.
Simulations of atmospheric phenomena at the Phoenix landing site with the Ames General Circulation Model

[1] Phoenix, the first NASA Mars Scout class mission, was designed to “follow the water” and study the polar region. Landing in late northern spring, Phoenix measured soil chemistry, near-surface water ice, and studied numerous atmospheric properties and weather phenomena. Here, we use atmospheric measurements made by Phoenix to test and calibrate the Ames General Circulation Model (GCM) and start the process of analyzing and interpreting the vast data set provided by this groundbreaking mission. The GCM reproduces surface pressures and temperatures within the measured diurnal and seasonal ranges. It also reproduces measured water ice cloud profiles with ground fogs forming after Ls = 120° and a separate cloud deck between 3 km and 6 km above the surface. Near-surface water vapor pressures have daytime maxima above 1 Pa in both the data and model. We find that frosts and fogs observed by Phoenix are correlated with the formation of high-pressure weather systems over the landing site.
Multiplicities and instabilities in film blowing

The mechanics of the blown film process are studied for Newtonian and viscoelastic models of the polymer melt. Multiple solutions of the governing equations are possible even for the Newtonian fluid, with the existence of more than one steady-state bubble profile for a given set of operating parameters; steady axisymmetric solutions vanish suddenly at critical combinations of operating variables. Several types of instabilities exist, including one that is analogous to “draw resonance.” The stability of the bubble to infinitesimal disturbances depends on the set of operating parameters that is controlled; control of the bubble inflation pressure is much less stable than control of the amount of inflating air, for example. Heat transfer is stabilizing.