cssi/SciSciGPT-SciSciNet huggingface dataset:
Phonon spectral function of a superconductor

Abstract The phonon spectral function of an acoustic phonon in a BCS superconductor is calculated at zero temperature and compared to the result for the normal metal. Shifts are found in the frequency and linewidth of the phonon depending on its wavevector. In addition to the phonon, the spectral function shows a structure around the gap energy of the superconductor, reflecting the increased polarizability of the superconducting electrons at this energy.
A randomized trial of diet in men with early stage prostate cancer on active surveillance: Rationale and design of the Men's Eating and Living (MEAL) Study (CALGB 70807 [Alliance])☆

Abstract Background Diet may substantially alter prostate cancer initiation and progression. However, large-scale clinical trials of diet modification have yet to be performed for prostate cancer. The Men's Eating and Living (MEAL) Study (CALGB 70807 [Alliance]) is investigating the effect of increased vegetable consumption on clinical progression in men with localized prostate cancer. Study design MEAL is a randomized, phase III clinical trial designed to test whether an intervention that increases vegetable intake will decrease the incidence of clinical progression in men with clinically localized prostate cancer on active surveillance. We are randomizing 464 patients to either a validated telephone-based diet counseling intervention or a control condition in which patients receive a published diet guideline. The intervention will continue for two years. The primary outcome variable is clinical progression defined by serum prostate-specific antigen (PSA) and pathological findings on follow-up prostate biopsy. Secondary outcome variables include incidence of surgical and non-surgical treatments for prostate cancer, prostate-cancer related patient anxiety and health-related quality of life. Conclusion The MEAL Study is assessing the effectiveness of a high-vegetable diet intervention for preventing clinical progression in men with localized prostate cancer on active surveillance.
Pulse width effect in ultrafast laser processing of materials

A systematic study of the influence of laser pulse width in ultrafast laser micromachining of silicon and stainless steel was carried out. Experiments were performed using a Ti:sapphire laser with 800 nm and 400 nm (frequency doubling) wavelengths in an air environment with a pulse duration ranging from 110 fs to 10 ps. Hole drilling and line cutting of silicon and stainless steel were studied. Structural details of the machined area were characterized using a number of techniques such as optical microscopy, atomic force microscopy and stylus profilometry. The effect of pulse width on melting was observed at ∼2.5 ps for stainless steel and at ∼5 ps for silicon. Also, the polarization effect on the laser machining is reported. The machined quality using femtosecond laser pulses with high energy fluence was found to be limited by the laser intensity contrast.
Near-IR absorbance changes and electrogenic reactions in the microsecond-to-second time domain in Photosystem I

The back-reaction kinetics in Photosystem I (PS I) were studied on the microsecond-to-s time scale in cyanobacterial preparations, which differed in the number of iron-sulfur clusters to assess the contributions of particular components to the reduction of P700+. In membrane fragments and in trimeric P700-FA/FB complexes, the major contribution to the absorbance change at 820 nm (delta A820) was the back-reaction of FA- and/or FB- with lifetimes of approximately 10 and 80 ms (approximately 10% and 40% relative amplitude). The decay of photoinduced electric potential (delta psi) across a membrane with directionally incorporated P700-FA/FB complexes had similar kinetics. HgCl2-treated PS I complexes, which contain FA but no FB, retain both of these kinetic components, indicating that neither can be assigned uniquely to a specific acceptor. These results suggest that FA- reduces P700+ directly and argue for a rapid electron equilibration between FA and FB, which would eliminate their kinetic distinction in a back-reaction. In PsaC-depleted P700-Fx cores, as well as in P700-FA/FB complexes with chemically reduced FA and FB, the major contribution to the delta A820 and the delta psi decay is a biphasic back-reaction of F-X (approximately 400 microseconds and 1.5 ms) with some contribution from A-1 (approximately 10 microseconds and 100 microseconds), the latter of which is variable depending on experimental conditions. The delta A820 decay in a P700-A1 core devoid of all iron-sulfur clusters comprises two phases with lifetimes of 10 microseconds and 130 microseconds (2.7:1 ratio). The biexponential back-reaction kinetics found for each of the electron acceptors may be related to existence of different conformational states of the PS I complex. In all preparations studied, excitation at 532 nm with flash energies exceeding 10 mJ gives rise to formation of antenna 3Chl, which also contributes to delta A820 decay on the tens-of-microsecond time scale. A distinction between delta A820 components related to back-reactions and to 3Chl decay can be made by analysis of flash saturation dependencies and by measurements of kinetics with preoxidized P700.
Filamentary Structures of Coronal White-Light Images

In the absence of magnetic field measurements of the solar corona, the density structure of white-light images has provided important insight into the coronal magnetic field. Recent work sparked by highly sensitive radio occultation measurements of path-integrated density has elucidated the density structure of unprocessed solar eclipse pictures. This paper does the same for processed images that reveal low-contrast small-scale structures, specifically Koutchmy’s edge-enhanced white-light image of the 11 August 1999 solar eclipse. This processed image provides visual evidence for two important results deduced from radio occultation measurements of small-scale density variations. First, in addition to the closed loops readily seen at the base of the corona in high-resolution EUV and soft X-ray images, open filamentary structures permeate the corona including active regions generally thought to be magnetically closed. Observed at the image resolution, the filamentary structures are 1° wide in latitude and an order of magnitude smaller than polar plumes. Second, although inhomogeneities that are convected along with the solar wind are also present, filamentary structures dominate the image because of their steeper density gradients. The quantitative profile of polarized brightness (pB) at the base of the corona shows that the filamentary structures have transverse density gradients that are proportional to their density. This explains why edge-enhanced images, limited in sensitivity to density gradients, tend to detect filamentary structures more readily in high-density regions (e.g., active regions, streamer stalks, and prominences) than in low-density polar coronal holes, and why filamentary structures seem more prevalent in solar eclipse pictures during solar maximum. The pB profile at the base of the corona also fills the gap in Doppler measurements there, reinforcing that open ultra-fine-scale filamentary structures observed by the radio measurements are predominantly radial and that they are an integral part of the radial expansion of the solar wind.
Successful renal transplantation in children with posterior urethral valves.

ABSTRACTPurpose: The treatment of children with posterior urethral valve (PUV) and end-stage renal disease can be challenging. Some series have had poor outcomes after renal transplantation with an increased risk of graft dysfunction and urinary tract infections. We present our experience with a pediatric population and compare it to all the other pediatric renal transplants done at our institution.Materials and Methods: We identified 10 patients with PUV who underwent a total of 13 renal transplants between 1990 and 2000. The comparison group included 120 transplants done in 95 patients during the same period. Cumulative allograft survival and function were recorded.Results: Overall patient survival in the PUV group was 100%. Mean age at transplant in the PUV group was 10.0 years and mean followup was 3.9 years. Six patients underwent high proximal urinary tract diversion, while the remainder had primary transurethral valve ablation. Three patients had bladder augmentation before transplantation. Cumulat...
How Much Can Spatial Training Improve STEM Achievement

Spatial training has been indicated as a possible solution for improving Science, Technology, Engineering, and Mathematics (STEM) achievement and degree attainment. Advocates for this approach have noted that the correlation between spatial ability and several measures of STEM achievement suggests that spatial training should focus on improving students’ spatial ability. Although spatial ability can be improved with targeted training, few studies have examined specifically the relation between spatial training and STEM achievement. In this brief report, we review the evidence to date for the effectiveness of spatial training. We argue that spatial training offers one of the many promising avenues for increasing student success in STEM fields, but research studies that show such training causally improve retention, achievement, and degree attainment remain outstanding.
High-pressure measurements of CO2 absorption near 2.7 μm: Line mixing and finite duration collision effects

Abstract Room-temperature, high-pressure (1–30 atm) measurements of CO2 absorption are carried out near 2.7 μm to study line mixing and finite duration collision effects on transitions in the ν1+ν3 and 2ν2+ν3 vibrational bands. Two distributed feedback diode lasers are used to measure CO2 transitions near 3631–3635 cm−1 and 3644–3646 cm−1, and an FTIR spectrometer covers the entire ν1+ν3 and 2ν2+ν3 bands from 3500 to 3800 cm−1. The experiments are carried out in CO2–air and CO2–Ar mixtures to observe the non-ideal effects under the influence of different perturbers. Measurements are compared with simulations using the Voigt line shape to analyze the deviation from the Lorentzian behavior with increasing gas density, and show significant deviation from this model at high gas densities. Line shape models using empirical corrections or dynamically based scaling laws are evaluated by comparison to the measured high-density spectra. Although none of the models is able to predict the measured spectra accurately, the line mixing model of Niro et al. [24] does an overall good job but overestimates the band centers by about 4–9%. In light of these observations, challenges of developing a CO2 sensor for high-pressure combustion applications are discussed.
Social Capital in an Impoverished Minority Neighborhood: Emergence and Effects on Children's Mental Health

PROBLEM: This study aims to describe and analyze neighborhood effects on children's mental health, focusing on the emergence and effects of Social Capital or informal social control. METHOD: Focus groups of Hispanic and African American families raising children in a low-income, minority neighborhood. FINDINGS: Parents’ alienation from and distrust of public sources of formal social control, such as policemen, prevented the emergence of positive informal social control. CONCLUSION: Psychiatric nurses and nurse practitioners must utilize public health and individual therapeutic approaches to prevent and treat children's mental health problems in disorganized, violent neighborhoods.
VENOUS PATCH GRAFT FOR PEYRONIE'S DISEASE. PART II: OUTCOME ANALYSIS

AbstractPurpose: We evaluate the results of tunical incision and venous patch grafting for correcting penile deformity in Peyronie's disease.Materials and Methods: In 112 patients with symptoms of Peyronie's disease for more than a year indications for surgery included penile shortening, persistent pain, severe curvature, penile narrowing or indentation and/or failure of previous surgery. Preoperative evaluation included determination of patient and partner expectation, potency status, circumcision status, measurement of penile length (short and long side) and saphenous vein, and color duplex ultrasonography to evaluate possible accessory vascular communication. Patients underwent plaque incision and venous patch grafting. The configuration, size and number of tunical incisions depended on the size and shape of the lesion. Lower and upper saphenous, and deep dorsal veins served as the graft materials. Postoperative followup was as long as 18 months.Results: In 96% of patients the penis became straight, wh...
Recession Effects in United States Public Sector Construction Contracting: Focus on the American Recovery and Reinvestment Act of 2009

AbstractThe 2009 American Recovery and Reinvestment Act (ARRA) was enacted to support the economy in response to the 2008–2009 global recession. The injection of construction funds into the public sector put pressure on public agencies to award contracts as quickly as possible in an effort to immediately stimulate the economy and help reconstruct the deteriorating infrastructure. This enabled contractors to move from private sector work into the public sector to stay afloat financially. As a result, an increase in competition for public project awards was observed combined with projects being awarded at a fast rate. The main objective of this paper is to investigate evidence of the level of contractor competition and the degree to which public agencies are expediting the award process during the bidding phase on ARRA construction projects. Both positive and negative impacts caused by this dynamic are examined. To achieve this objective, the research looked into the bidding phase of ARRA construction proje...
Graeme Smith, A Short History of Secularism

(2010). Graeme Smith, A Short History of Secularism. Political Theology: Vol. 11, No. 1, pp. 165-169.
Stability and entropy production in electrical circuits

A number of the theorems expounded by Prigogine, Glansdorff and their collaborators are translated into electrical circuit terminology and their validity and significance discussed. The simultaneous occurrence of inductors and capacitors represents a situation not envisioned in the chemically oriented discussions and imposes some limitations. The electrical terminology also leads to “dual” theorems, in which voltage sources are replaced by current sources. The validity of the theorems in situations in which fluctuations are critical to the relaxation behavior is analyzed. The “excess entropy production” theorem is only valid if the circuit relaxation can be described by single-valued macroscopic variables, but not if it must be described by distribution functions. We stress that no purely local characterization, which examines a multistable system only in the neighborhoods where it occurs with high probability, can predict or characterize the steady state.
A 1.8-THz quantum cascade laser operating significantly above the temperature of ℏω/kB

Quantum cascade lasers can operate at terahertz frequencies because they use intraband, rather than interband, transitions in semiconductor nanostructures. However, they seemed to have reached a ceiling in terms of maximum operating temperature. This trend has now been broken with the introduction of a new scheme for charge injection.
Inhibition of G protein-coupled receptor trafficking in neuroblastoma cells by MAP 4 decoration of microtubules

One mechanism for the reappearance of G protein-coupled receptors after agonist activation is microtubule-based transport. In pressure-overload cardiac hypertrophy, there is downregulation of G protein-coupled receptors and the appearance of a densified microtubule network extensively decorated by a microtubule-associated protein, MAP 4. Our hypothesis is that overdecoration of a dense microtubule network with this structural protein, as in hypertrophied myocardium, would impede receptor recovery. We tested this hypothesis by studying muscarinic acetylcholine receptor (mAChR) internalization and recovery after agonist stimulation in neuroblastoma cells. Exposure of cells to carbachol, a muscarinic receptor agonist, decreased membrane receptor binding activity. After carbachol withdrawal, receptor binding recovered toward the initial value. When microtubules were depolymerized before carbachol withdrawal, mAChR recovery was only 44% of that in intact cells. Cells were then infected with an adenovirus containing MAP 4 cDNA. MAP 4 protein decorated the microtubules extensively, and receptor recovery upon carbachol withdrawal was reduced to 54% of control. Thus muscarinic receptor recovery after agonist exposure is microtubule dependent, and MAP 4 decoration of microtubules inhibits receptor recovery.
LAND TENURE, HOUSEHOLD STRUCTURE, AND FERTILITY: AGGREGATE ANALYSES OF FIFTEENTH‐CENTURY RURAL TUSCANCOMMUNITIES

In some settings, sharecropping is associated with large extended families, high fertility, and early age of marriage. These demographic practices are often considered to be labor strategies for working extensive share‐tenancies. Where agricultural production is primarily labor intensive, landlords can increase their income, within certain limits, by maximizing the number of adult workers. If landlords hold considerable power over their tenants, they may have a large influence on demographic practices. Although this relationship between sharecropping and some of these demographic practices is found throughout much of history in northern Italy, the evidence is less clear for fifteenth‐century Tuscany. Herlihy and Klapisch‐ Zuber's study of the Catasto of 1427, a set of tax declarations, found no relation between household structure and land tenure. Some of their work suggested that fertility was higher among sharecroppers, but this relationship was not specified in detail. They did not consider the relationship between land tenure and age of marriage. This paper reconsiders the relationship between land tenure, household structure, fertility, and age of marriage. To try to correct for problems with Herlihy and Klapisch‐Zuber's land tenure variable, their data were aggregated to the administrative unit of analysis. The aggregated data show that sharecropping in rural Tuscany in 1427 was associated with household extension, high fertility, and early age of marriage, although the magnitude of this relationship was not large. Possible reasons for this weak relationship are discussed.
Control of metabolism and synthesis of macromolecules in normal and ischemic heart.

Abstract A brief review of some aspects of myocardial metabolism related to myocardial infarction is presented. Some of the mechanisms adjusting oxidative and glycolytic metabolism to cardiac energy requirements are discussed. Also considered are mechanisms which lead to enhanced glycogenolysis and glycolysis in anaerobic or ischemic heart. Emphasis is also placed on the considerable capacity of cardiac tissue for growth and repair, and for renewal of intracellular constituents. This contrasts with the apparent inability of adult cardiac muscle cells to increase in number or to regenerate after tissue destruction.
Indirect assessment of 4,4'-diphenylmethane diisocyanate (MDI) exposure by evaluation of specific humoral immune responses to MDI conjugated to human serum albumin.

Background A study of occupational asthma among workers exposed to 4,4′-Diphenylmethane Diisocyanate (MDI). Objective To demonstrate if serum concentrations of MDI-specific IgG or IgE are sensitive biological markers of disease or of MDI exposure. Methods The study group consisted of nine MDI-exposed workers and nine nonexposed workers. Air sampling for MDI and polymethylene polyphenyl isocyanate, occupational and medical histories, respiratory physical exams, pre- and postshift spirometry, and self-administered peak expiratory flow rates were performed. Serum specific IgE and IgG antibodies to an MDI-human serum albumin (HSA) conjugate were assayed by the radioallergosorbent test and the enzyme-linked immunosorbent assay, respectively, and compared to nine nonexposed laboratory controls. Results No definitive cases of occupational asthma were documented. The mean level of MDI-specific IgG was significantly greater among exposed workers compared to nonexposed workers and laboratory controls (p = 0.04). Mean levels of TDI and HDI-specific IgG were also increased. Conclusion This study demonstrates that serum concentrations of MDI-specific IgG appear to be a moderately sensitive biological marker of MDI exposure, but not an indicator of occupational asthma. Workers with IgG antibodies specific for one diisocyanate-HSA conjugate exhibit cross-reactivity to antigens prepared with other diisocyanates. Am. J. Ind. Med. 33:471–477, 1998. Published 1998 Wiley-Liss, Inc.1
Sublattices of a free lattice

Professor R. A. Dean has proved (1, Theorem 3) that a completely free lattice generated by a countable partially ordered set is isomorphic to a sublattice of a free lattice. In particular, it follows that a free product of countably many countable chains can be isomorphically embedded in a free lattice. Generalizing this we show (2.1) that the class of all lattices that can be isomorphically embedded in free lattices is closed under the operation of forming free lattice-products with arbitrarily many factors. We also prove (2.4) that this class is closed under the operation of forming simply ordered sums with denumerably many summands. Finally we show (2.7) that every finite dimensional sublattice of a free lattice is finite.
A study of temperature effect on vertically aligned carbon nanofibers for bio/chemical sensors development

One of the major limitations in the development of ultrasensitive electrochemical biosensors based on one dimensional nanostructure is the difficulty involved with reliably fabricating nanoelectrode arrays (NEAs). In this work, to ensure nanoelectrode behavior and higher sensitivity, Vertically Aligned Carbon Nano Fibers (VACNF) are precisely grown on 100 nm Ni dots with 1µm spacing on each micro pad. However, in order to examine the quality and measure the height and diameter of the VACNFs, a surface detection and measurement tool at the nanoscale level is employed. In this paper, we introduce an approach to measure these nano-scale features through Atomic Force Microscope (AFM). With this method, both the 2D and 3D images of sample surface are generated and the sizes of carbon nanofibers are obtained with statistical analysis. Furthermore, temperature effect on the dimensions of VACNFs is studied.
Characterization of topographic EEG changes when smoking a cigarette

The acute effects of cigarette smoking on the human electroencephalogram (EEG) were investigated by the topographic mapping technique. Twenty-six subjects participated in this study, which involved sham smoking and real smoking of preferred cigarettes. Effects of smoking were analyzed by statistical and multivariate analysis. Analysis of variance andt-test results showed a significant decrease in the theta and alpha1 bands but a significant increase in the alpha2, beta1, and beta2 bands. Factor analysis and cluster analysis showed that there were two or three independent regions on the scalp that indicate the effects of smoking on topographic EEG. A hypothesis was formed that smoking has different effects on human EEG profiles for different brain regions and that there are individual variations in the EEG responses to smoking.
Characterization of Discrete Subpopulations of Progenitor Cells in Traumatic Human Extremity Wounds

Here we show that distinct subpopulations of cells exist within traumatic human extremity wounds, each having the ability to differentiate into multiple cells types in vitro. A crude cell suspension derived from traumatized muscle was positively sorted for CD29, CD31, CD34, CD56 or CD91. The cell suspension was also simultaneously negatively sorted for either CD45 or CD117 to exclude hematopoietic stem cells. These subpopulations varied in terms their total numbers and their abilities to grow, migrate, differentiate and secrete cytokines. While all five subpopulations demonstrated equal abilities to undergo osteogenesis, they were distinct in their ability to undergo adipogenesis and vascular endotheliogenesis. The most abundant subpopulations were CD29+ and CD34+, which overlapped significantly. The CD29+ and CD34+ cells had the greatest proliferative and migratory capacity while the CD56+ subpopulation produced the highest amounts of TGFs1 and TGFs2. When cultured under endothelial differentiation conditions the CD29+ and CD34+ cells expressed VE-cadherin, Tie2 and CD31, all markers of endothelial cells. These data indicate that while there are multiple cell types within traumatized muscle that have osteogenic differentiation capacity and may contribute to bone formation in post-traumatic heterotopic ossification (HO), the major contributory cell types are CD29+ and CD34+, which demonstrate endothelial progenitor cell characteristics.
Are there race-dependent endothelial cell responses to exercise?

African Americans have endothelial dysfunction which likely contributes to their high prevalence of hypertension. Endothelial cell responses to stimuli could play a role in the development of endothelial dysfunction and hypertension. High physiological levels of vascular laminar shear stress can profoundly alter endothelial cell phenotype. It is not known whether there are race-dependent endothelial cell responses to laminar shear stress.
Liquid phase controlled mass transfer to bubbles in cocurrent turbulent pipeline flow

Abstract Liquid-phase controlled turbulent-flow mass-transfer coefficients for bubbles flowing cocurrently with liquids in a pipeline were determined using transient response experiments. Five different mixtures of glycerol and water were used in which dissolved oxygen was transferred to small helium bubbles flowing with the liquids in both vertical and horizontal directions. Two general types of behavior were observed: 1. (1) Above pipe Reynolds numbers for which turbulent inertial forces dominated over gravitational forces, horizontal and vertical flow mass-transfer coefficients were essentially equal with a recommended correlation of Sh/Sc 1/2 =0·34 Re 0 ·94( d vs / D ) 1·0 . The observed Reynolds number exponent agreed generally with other data from the literature for cocurrent pipeline flow but did not agree with expectation based on equivalent power dissipation comparisons with agitated vessel data. 2. (2) At values of Reynolds number below that marking the equivalence of horizontal and vertical flow coefficients, the horizontal-flow coefficients continued to vary according to Eq. (1) until, at low flows, severe stratification of the bubbles made operation impractical. The vertical-flow coefficients, however, passed through a minimum with decreasing Reynolds numbers and underwent transitions to approach constant asymptotes characteristic of bubbles rising through the quiescent liquid. An expression was developed for the relative importance of turbulent inertial forces compared with gravitational forces, F i / F g . This expression introduced a “turbulence” Froude number which served as a good criterion for establishing the pipe Reynolds numbers above which horizontal and vertical flow mass-transfer coefficients were equivalent. In addition, it proved to be a useful linear scaling factor for calculating the vertical-flow coefficients in the above mentioned transition region. The turbulent inertial forces were equated with drag forces to obtain bubble-mean Reynolds numbers which were substituted into Frossing-type equations to determine the mass-transfer Sherwood numbers. The resulting pipe Reynolds numbers exponent agreed well with the observed data.
Immunoreactive inhibin decreases following bilateral ovariectomy and during the postovulatory rise of FSH in Syrian hamsters.

Abstract Inhibin is a heterodimeric glycoprotein which may regulate FSH synthesis and secretion as well as follicular development and maturation. The source and physiological role of inhibin have not been established for the hamster, although several investigators have suggested that this hormone may function in the regulation of FSH in this species. The major objectives of the present studies were to develop a radioimmunoassay (RIA) for the measurement of inhibin in hamster serum and tissue, to identify the primary source of inhibin and to examine the relationship between inhibin and FSH during the estrous cycle. A sensitive, accurate and specific RIA was developed and utilized to measure changes in circulating levels of immunoreactive inhibin (ir-inh-α) following bilateral gonadectomy and throughout the estrous cycle. Circulating ir-inh-α declined rapidly and significantly following bilateral gonadectomy in female hamsters suggesting a gonadal source. Serum FSH concentrations increased following the decline in serum ir-inh-α levels. In the adult female hamster circulating ir-inh-α increased gradually throughout diestrus, peaked at the time of the preovulatory gonadotropin surge, then declined to a nadir on the morning of estrus. Changes in ovarian inhibin subunit mRNAs were examined throughout the estrous cycle and correlated with changes observed in circulating irinh-a levels. Observed significant reductions in the relative amount of inhibin mRNAs and serum concentrations of ir-inh-α during early estrus may moderate the amount and duration of the secondary FSH rise and thus contribute to the regulation of follicle recruitment in the hamster.
Consequences of diffuse and channelled porous melt migration on uranium series disequilibria

Magmas erupted at mid-ocean ridges (MORB) result from decompression melting of upwelling mantle. However, the mechanism of melt transport from the source region to the surface is poorly understood. It is debated whether melt is transported through melt-filled conduits or cracks on short time scales ( ∼ 103–104 yrs). Radiogenic excess 226Ra in MORB indicates that melt is transported from the melting region on time scales less than the half life of 226Ra (∼1600 yrs), and has been used to argue for fast melt transport from the base of the melting column. However, excess 226Ra can be generated at the bottom of the melt column, during the onset of melting, and at the top of the melt column by reactive porous flow. Determining the depth at which 226Ra is generated is critical to interpreting the rate and mechanism of magma migration. A recent compilation of high quality U-series isotope data show that in many young basalts, 226Ra excess in MORB is negatively correlated with 230Th excess. The data suggest that 226Ra excess is generated independently of 230Th excess, and cannot be explained by “dynamic” or fractional melting, where observed radiogenic excesses are all generated at the base of the melt column. One explanation is that the negative correlation of activity ratios is a result of mixing of slow moving melt that has travelled through reactive, low-porosity pathways and relatively fast moving melt that has been transported in unreactive high-porosity channels. We investigate this possibility by calculating U-series disequilibria in a melting column in which high-porosity, unreactive channels form within a low-porosity matrix that is undergoing melting. The results show that the negative correlation of 226Ra and 230Th excesses observed in MORB can be produced if ∼60% of the total melt flux travels through the low-porosity matrix. This melt maintains 226Ra excesses via chromatographic fractionation of Ra and Th during equilibrium transport. Melt that travels through the unreactive, high-porosity channels is not able to maintain significant 226Ra excesses because Ra and Th are not fractionated from each other during transport and the transport time for melt in the channels to reach the top of the melt column is longer than the time scale for 226Ra excesses to decay. Mixing of melt from the high porosity channels with melt from the low-porosity matrix at the top of the melting column can produce a negative correlation of 226Ra and 230Th excesses with the slope and magnitude observed in MORB. This transport process can also account for other aspects of the geochemistry of MORB, such as correlations between La/Yb, αSm/Nd, and Th/U and 226Ra and 230Th excess.
Drug development for neglected diseases - the trouble with FDA review vouchers.

A new federal program will give the sponsor of a drug for a tropical disease a “voucher” entitling the company to expedited FDA review of a new drug application for any other product it makes. Dr. Aaron Kesselheim writes that as enacted, however, priority-review vouchers represent an inefficient and potentially dangerous way of encouraging research into tropical diseases.
Effects of capsaicin on vascular smooth muscle.

1) Acute administration of capsaicin in vitro produced either vascular smooth muscle contraction (cat middle cerebral artery) or smooth muscle relaxation (guinea pig carotid artery and thoracic aorta). 2) Prior in vivo treatment with capsaicin abolished the relaxation response of guinea pig vessels to acute capsaicin. Instead a contractile response was seen after chronic capsaicin treatment, suggesting that the relaxation response produced by capsaicin is due to release of a vasodilator substance. 3) Substance P caused relaxation in both cat cerebral arteries and the guinea pig thoracic aorta, an effect which was abolished or reduced by endothelial damage. However, responses to acute capsaicin were not altered by endothelial damage, suggesting that substance P does not mediate the relaxation response to acute capsaicin administration. 4) Exposure to capsaicin in vitro did not affect the neurogenic vasodilator response of cat cerebral arteries and did not alter substance P levels. 5) Therefore, it was concluded that the acute effect of capsaicin is composed of two components. A contractile response is most likely due to direct effects on vascular smooth muscle, while a relaxation response is attributed to release of an as yet unidentified bioactive substance distinct from substance P.
Waking up the Back Row: Using Effective Communicating-to-Learn Strategies in Education Courses

Abstract How can university faculty use communicating-to-learn activities to enliven discussions, check understanding, and assess learning? By incorporating various reading, writing, listening, speaking, and thinking strategies into their classes, faculty are teaching through example and are making classes invigorating. As such, their undergraduate and graduate elementary and secondary students can use similar techniques in their preK-12 classes. Along with providing detailed descriptions of creative activities, this article examines the research and includes additional resources, such as university websites with descriptions of writing-to-learn suggestions.
Revisiting matrix representations of the braid group

The Burau matrix representation of the braid group Bn is faithful if certain n-square matrices M 1,M 2,…,Mn freely generate a free group G. The author obtains properties of the matrices Mi which indicate that G is indeed freely generated by the Mi .
MicroRNA in TLR signaling and endotoxin tolerance

Toll-like receptors (TLRs) in innate immune cells are the prime cellular sensors for microbial components. TLR activation leads to the production of proinflammatory mediators and thus TLR signaling must be properly regulated by various mechanisms to maintain homeostasis. TLR4-ligand lipopolysaccharide (LPS)-induced tolerance or cross-tolerance is one such mechanism, and it plays an important role in innate immunity. Tolerance is established and sustained by the activity of the microRNA miR-146a, which is known to target key elements of the myeloid differentiation factor 88 (MyD88) signaling pathway, including IL-1 receptor-associated kinase (IRAK1), IRAK2 and tumor-necrosis factor (TNF) receptor-associated factor 6 (TRAF6). In this review, we comprehensively examine the TLR signaling involved in innate immunity, with special focus on LPS-induced tolerance. The function of TLR ligand-induced microRNAs, including miR-146a, miR-155 and miR-132, in regulating inflammatory mediators, and their impact on the immune system and human diseases, are discussed. Modulation of these microRNAs may affect TLR pathway activation and help to develop therapeutics against inflammatory diseases.
Difficult reputations and the social reality of occupational medicine.

This response to Tee Guidotti's (2008) critique of Elaine Draper's The Company Doctor: Risk, Responsibility, and Corporate Professionalism (2003) argues that a forthright examination of the conflicts of those working in the field of occupational medicine is essential to maintaining the health of the profession and to promoting constructive policies. Research for The Company Doctor reveals how doctors walk a tightrope of professional demands on them. The author describes how corporate employment affects medicine and science and how professionals working in corporations are subject to the decisions of company managers and to economic and legal imperatives stemming from their status as corporate employees. Analyzing company doctors' role in confronting toxics and responding to liability fears in corporations, the author argues that problems of lost credibility, stigmatization, and tarnished reputation that company doctors describe largely stem from the organizational constraints, economic interests, and othe...
Allergic bronchopulmonary aspergillosis in pediatric practice.

Twelve cases of allergic bronchopulmonary aspergillosis in the pediatric age group are reported. The average age of diagnosis was 14.5 years with a range from 6 to 18 years. All patients had a history of pulmonary infiltrations or atelectasis or both documented by chest radiographs. Eight patients had bronchograms or tomograms, and seven of them showed proximal bronchiectasis. Total serum IgE concentrations were elevated in all patients. Precipitating antibodies against Aspergillus fumigatus were positive in all patients at the time of diagnosis, and became negative in some after therapy. The specific IgE or IgG antibody activity against Af was elevated in all 12 patients. After prednisone was started the total serum IgE sharply declined to a plateau and remained at this level until a flare of allergic aspergillosis occurred. A flare of allergic aspergillosis is characterized by an increasing total serum IgE concentration followed by pulmonary infiltration. Clinical and roentgenologic improvements were observed after steroid therapy. The importance and methods of early diagnosis in the pediatric population are discussed.
Rapidly Rising Incidence of Cerebrospinal Fluid Shunting Procedures for Idiopathic Intracranial Hypertension in the United States, 1988–2002

OBJECTIVE: Obesity, a major risk factor for idiopathic intracranial hypertension (IIH), is rapidly increasing in all ages of the United States population. We studied trends in the incidence of cerebrospinal fluid (CSF) shunts for IIH in the United States between 1988 and 2002, using a national hospital discharge database. METHODS: This was a retrospective study using the Nationwide Inpatient Sample and robust weighted least-squares regression, adjusted for stratified survey methodology. RESULTS: There were 2779 admissions for CSF shunting procedures (new or revision) in IIH patients in the database. In-hospital mortality for new shunts was 0.5% (0.9% for ventricular shunts and 0.2% for lumbar shunts). The estimated total United States caseload of CSF shunting procedures for IIH increased 350% between 1988 and 2002 (P 44 yr) increased 240% during the study period. Bariatric procedures (e.g., gastric bypass) increased very rapidly in incidence since 1998, with nearly 200 such procedures performed on IIH patients in 2002. CONCLUSION: The incidence of CSF shunting for IIH is increasing in the population of the United States at about the same relative rate as morbid obesity. Studies to establish the best shunting method in IIH and to explore alternative treatment strategies, such as optic nerve sheath fenestration and bariatric surgery, are urgently needed.
Talk global, act local—patterning the Arabidopsis embryo

The primary axis and main tissue types of Arabidopsis are laid down in the early embryo. Apical-to-basal auxin flux functions as a global organizer of the axis, and recent reports are clarifying our mechanistic understanding of how a graded auxin distribution is generated and interpreted. Polar targeting of PIN transporters in the cells of the embryo is dynamic and linked to their phosphorylation status, suggesting a flexible mechanism for regulating auxin flux in space and time. PLETHORA transcription factors then interpret the graded auxin distribution to provide positional values along the axis in a dose-dependent manner. A comparable framework for tissue patterning in the radial dimension is still lacking, although cell surface signaling probably plays a key role.
Exploring learning experience in textile and apparel management: study abroad in El Salvador

Global economy has fundamentally changed the nature of business as well as the mission of higher education. Professional academic programmes, such as textiles and apparel, are ultimately responsible for preparing students to be industry-ready and, thus, various curricula have been developed to address this new need of the industry (Fair et al. Clothing and Textiles Research Journal 1990;8(2):29–37). Particularly, experiential learning has shown to be effective at student learning; international experience learning has become popular in the education literature. While most previous research has focussed on the process and outcomes of new curricula, the study analysed students' journals from a short-term study aboard curriculum to capture how students grasp, conceptualise, reflect on and experiment with new experiences under an experiential learning theory framework (Kolb, Experiential learning: experience as the source of learning and development; 1984). Eight themes emerged; two from each of the four lear...
Nuclear Energy Level Argument for a Spheroidal Nuclear Model

Recently there has been notable success, particularly by Maria Mayer, in explaining many nuclear phenomena including spins, magnetic moments, isomeric states, etc. on the basis of a single particle model for the separate nucleons in a spherical nucleus. The spherical model, however, seems incapable of explaining the observed large quadrupole moments of nuclei. In this paper it is shown that an extension of the logic of this model leads to the prediction that greater stability is obtained for a spheroidal than for a spherical nucleus of the same volume, when reasonable assumptions are made concerning the variation of the energy terms on distortion. The predicted quadrupole moment variation with odd $A$ is in general agreement with the experimental values as concerns variation with $A$, but are even larger than the experimental values. Since the true situation probably involves considerable "dilution" of the extreme single particle model, it is encouraging that the present predictions are larger rather than smaller than the experimental results. A solution is given for the energy levels of a particle in a spheroidal box.
Stochastic equation for the erosion of inclined topography

We present a stochastic equation to model the erosion of topography with fixed inclination. The inclination causes the erosion to be anisotropic. A zero-order consequence of the anisotropy is the dependence of the prefactor of the surface height-height correlations on direction. The lowest higher-order contribution from the anisotropy is studied by applying the dynamic renormalization group. In this case, assuming an inhomogenous distribution of soil material, we find a one-loop estimate of the roughness exponents. The predicted exponents are in good agreement with new measurements made from seafloor topography.
On the optimality of hysteresis operators in signal processing and communication systems

This paper demonstrates that hysteresis operators are the optimal estimators for a large class of estimation and decision problems. This class of problems arises whenever a cost is associated with actions needed to process changes in the estimates or decisions. A simple example related to least-squares estimation is used to illustrate and motivate the developments in this paper. Subsequently, the problem of mean-square estimation with minimal cost of actions is investigated. These results provide a justification for the use of hysteresis in many practical signal processing and communication applications.
Separation of dansyl amino acids in a single analysis

Abstract The reagent, 1-dimethylaminonaphthalene-5-sulfonyl chloride (dansyl-Cl) 1 was first proposed as an N-terminal reagent for proteins and peptides by Gray and Hartley (1, 2). They reported separation of most of the dansyl amino acids by high-voltage electrophoresis on paper at pH 4.4. Dansyl-serine, -proline, and -alanine, which migrate together in this system, could be resolved electrophoretically at pH 12.7. The advantages of this method are twofold: the derivatives retain the relative charge properties of the parent amino acids, and their ultraviolet fluorescence extends the sensitivity to 1 nanomole, a 100-fold increase over the DNP method. By using this method on 20 nmoles of a peptide from cytochrome C-551 in conjunction with the Edman degradation, the N-terminal sequence for 6 amino acids was determined (2). Since the original publications of Gray and Hartley, others have reported separation of dansyl amino acids by thin-layer chromatography on silica gel (3–5) and aluminum oxide (3) using various organic solvent systems. None of these methods, however, could give identification of all dansyl amino acids in a single analysis. The method presented here utilizes a combination of adsorption chromatography and high-voltage electrophoresis on cellulose thin-layer plates. The lower limit of detection of dansyl amino acids on thin-layer plates is ten picomoles.
Iterative channel estimation and decoding of pilot symbol assisted LDPC coded QAM over flat fading channels

This paper considers pilot symbol assisted LDPC coded 16 QAM over flat fading channels. Iterative channel estimation and decoding method with hard, soft and threshold-controlled hard decision feedback is suggested to improve performance. We find that the hard decision feedback performs best with the 16 QAM modulation and Wiener smoothing. For faster fading case with normalized Doppler spread f/sub d/T/sub s/=0.02, 1.8 dB performance improvement is achieved over PSAM system, with only 1.5 dB gap to the perfect CSI performance. For slower fading case f/sub d/T/sub s/=0.005, 1.0 dB performance improvement is achieved with only 0.3 dB gap to the perfect CSI performance.
Log-penalized linear regression

Regularization penalties are commonly used in linear regression to reduce overfitting (l). We introduce a log regularization penalty, motivated by a minimum-description-length (MDL) perspective (2) and from ideas in algorithmic complexity (3), and com- pare it to the more commonly used penalties known as ridge regreesion and the lasso (l). I. DISCUSSION
The Seasonality of Schizophrenic Births: A Reply to Marc S. Lewis

Lewis contends that the previously demonstrated finding of seasonality of schizophrenic births is a statistical artifact due to the age-incidence effect. If Lewis is correct, then (1) January should have the highest schizophrenic birthrate, (2) December should have the lowest schizophrenic birthrate, (3) the Southern Hemisphere should show the same pattern as the Northern Hemisphere, and (4) the ageincidence effect should be more marked in younger age cohorts. None of these findings have been borne out by studies to date. It is concluded that the seasonality of schizophrenic birthrates is a replicable finding, and should be considered one of the more intriguing clues to the etiology of this disease.