cssi/SciSciGPT-SciSciNet huggingface dataset:
Stresses within elastic circular cylinders loaded uniaxially and triaxially

Abstract The elastic deformation of circular cylinders of rock is one of the basic problems in rock mechanics; it is fundamental to the understanding of standard laboratory tests on rock specimens and to design of pillars in mines. A closed-form solution has been derived for stresses within cylindrical elastic specimens subjected to end-boundary conditions encountered in laboratory testing. The boundary conditions are: Perfect confinement, in which radial expansion of the ends of the specimen is prevented; direct contact, in which the specimen is placed directly against the platens of the loading machine; uniform loading, in which steel inserts of a certain design are placed between the specimen and the platens and in which strains on the cylindrical surfaces of the specimen are uniform; teflon inserts, in which wafers of teflon, 0·005 in. thick, are placed between the specimen and the platens; and neoprene inserts, in which wafers of neoprene rubber, 0·063 in. thick, are placed between the specimen and the platens. The experimental and theoretical analyses of stresses and strains in rock and steel cylinders indicate that ‘uniaxially-loaded’ specimens in most laboratory tests are actually triaxially stressed. The stresses are different in different directions and they vary from point-to-point within specimens. For ‘frictional’ boundary conditions, where the specimens tend to expand more than the platens of the loading machine, including perfect confinement and direct contact, the absolute values of maximum and minimum stress concentrations and the stress gradients increase with increasing friction. Highly nonuniform stress distributions are developed under end conditions of perfect confinement. The magnitudes of the radial and circumferential stresses decrease as the expansion of the platens or the inserts approaches that of the specimens. For teflon and neoprene end-boundary conditions, involving platens or inserts that expand more than the specimen, the rate of change of stress increases as the expansional effect of the end-inserts increases. The more expansive the end-inserts, the more nonuniform are the stress distributions within specimens.
Oxidative Stress and Inflammation in Atrial Fibrillation: Role in Pathogenesis and Potential as a Therapeutic Target

Atrial fibrillation (AF) is one of the most prevalent and vexing cardiovascular conditions. Available treatments for AF based on ion channel blockade are only poorly effective. The fundamental mechanisms that underlie AF are still not clearly understood, and likely vary depending on the etiology of AF. In older individuals with senile AF, likely mechanisms include abnormal calcium cycling, oxidant stress, and deleterious inflammatory responses. Clinical and experimental evidence is provided to support the role of oxidant and inflammatory mechanisms in AF. On the basis of these studies, the prospects of manipulating oxidant and inflammatory pathways as targets for therapeutic intervention are discussed.
Effects of social reorganization on cellular immunity in male cynomolgus monkeys

Exposure to acute stressors has been shown to impair cellular immunity in human beings and other animal species. Comparatively little is known, however, about the effects of long-term stressors on immune function and how individual behavioral characteristics may mediate differences in immune function and clinical disease susceptibility. To determine the effects of social stress on cellular immunity and reactivation of a latent herpesvirus, 20 Herpes B virus-positive male cynomolgus monkeys were exposed to four periodic reorganizations of social group memberships over 5 months. Observations were made to categorize individuals as high or low in expression of aggressive, fearful, and affiliative behaviors. Complete blood counts, lymphocyte proliferation tests, and natural killer cell cytotoxicity assays were performed immediately before and 4 days after reorganizations. Herpesvirus-specific immunoglobulin G antibody levels were measured, and oral and conjunctival swabs were cultured for virus. Reorganization was associated with increased lymphocyte counts (P = 0.0009) and decreased lymphocyte proliferation in response to phytohemagglutinin (P < 0.005), particularly among monkeys showing high levels of fear (P = 0.0137). High-aggressive monkeys showed lower baseline natural killer cell activity (P = 0.0013) and higher lymphocyte counts (P = 0.013) than low-aggressive monkeys. Herpesvirus antibody titers decreased over time (P < 0.004) and no positive virus cultures were obtained. Measures of cellular immunity and behavior were unrelated to virus-specific antibody titers. These results suggest that repeated exposure to a social stressor alters several measures of cellular immunity, and that some of these changes may be predicted by individual differences in agonistic behavior. In contrast to human studies, the results suggest that some psychological stressors may not cause reactivation of a common herpesvirus in this species. © 1996 Wiley-Liss, Inc.
Sport Education and Multiple Intelligences: A Path to Student Success

One of the unique challenges associated with teaching is learning how to develop lessons and curricula that meet the needs of all students. In physical education, teachers must consider a number of...
Dynamic quench of NbTi in pressurized He4: 1. dual lambda transition during transient heat transfer

Abstract New transient phase transition phenomena are reported for near-isobaric temperature excursions caused by a step input in heating power supplied from a composite conductor NbTi/Cu to superfluid He II above its thermodynamic critical pressure Pc. Transient triple — phase phenomena are found not only below Pc but also above Pc during dual-lambda transitions from He II to He I and from pseudo-liquid to pseudo-vapour of He I. Consequences are presented for stabilization of superconducting magnets.
The anaesthetic management of the patient with tuberous sclerosis complex

Summary Tuberous sclerosis is a congenital neurocutaneous complex resulting in the uncontrolled growth of hamartomas in the body. This report describes the anaesthetic management of a 17-year-old male with tuberous sclerosis complex who developed haemorrhage into angiomyolipomas of the kidney. The literature which is pertinent to the anaesthesiologist is reviewed.
Control of acute cutaneous herpes simplex virus infection : T cell-mediated viral clearance is dependent upon interferon-γ (IFN-γ)

Abstract It is well established that T lymphocytes play a critical role in the control and clearance of herpes simplex virus (HSV) infections. However, the role of the CD4 + and CD8 + T cell subsets in the recovery process has not been clearly elucidated. Cutaneous HSV infection of the footpad tissue of C57BL/6 (B6) mice provides a model to determine the relative contribution of each T cell subset during the important early phase of the response to infection. In this study, we observed that the elimination of mature peripheral T lymphocytes by depletion in vivo with a combination of CD4- and CD8-specific monoclonal antibodies prevented recovery from acute infection in this model. However, mice depleted of either the CD4 + or CD8 + subpopulation alone recovered completely, with only a slight delay in the total clearance of infectious virus, Adoptive transfer studies revealed that lymph node cells from donor mice selectively depleted of either CD4 + or CD8 + T cell subset in vivo , or from normal donors selectively depleted in vitro , were able to mediate recovery. As CD4-depleted mice fail to generate a CD8 + T cell-mediated cytolytic T lymphocyte (CTL) response, this suggested that the control of cutaneous HSV infections may be mediated by a cytokine-dependent mechanism common to both the CD4 + and CD8 + T cell subpopulations. It was subsequently found that the neutralization of IFN-γ in vivo diminished the ability of mice to clear infectious HSV from the skin, and treatment with anti-IFN-γ in vivo ablated the ability of transferred T cells to mediate recovery. These studies suggested that IFN-γ-mediated mechanisms play a critical role in the control of and recovery from acute cutaneous HSV infection.
Investor Attention and Time‐varying Comovements

This paper analyses the effect of an increase in market-wide uncertainty on information flow and asset price comovements. We use the daily realised volatility of the 30-year treasury bond futures to assess macroeconomic shocks that affect market-wide uncertainty. We use the ratio of a stock's idiosyncratic realised volatility with respect to the S&P500 futures relative to its total realised volatility to capture the asset price comovement with the market. We find that market volatility and the comovement of individual stocks with the market increase contemporaneously with the arrival of market-wide macroeconomic shocks, but decrease significantly in the following five trading days. This pattern supports the hypothesis that investors shift their (limited) attention to processing market-level information following an increase in market-wide uncertainty and then subsequently divert their attention back to asset-specific information.
Is acetylcysteine effective in preventing contrast-related nephropathy? A meta-analysis.

Purpose Clinical trials evaluating acetylcysteine for the prevention of contrast-related nephropathy have reported mixed results. Although previous meta-analyses have concluded that acetylcysteine is beneficial, the recent availability of additional trials calls for reassessment of current evidence. Methods We performed a computerized search to identify relevant published and unpublished randomized clinical trials that evaluated acetylcysteine for the prevention of contrast-related nephropathy. Abstracted data from each trial included assessments of clinical outcomes, trial quality, and additional characteristics. The primary outcome of interest was the incidence of nephropathy after contrast administration. Data were combined using random-effects models with the performance of standard tests to assess for heterogeneity and publication bias. Subgroup analyses were also performed. Results Twenty trials involving 2195 patients met our inclusion criteria. Trials varied in patient demographic characteristics, inclusion criteria, dosing regimens, and trial quality. The summary risk ratio for contrast-related nephropathy was 0.73 (95% confidence interval: 0.52 to 1.0; P = 0.08), a nonsignificant trend towards benefit in patients treated with acetylcysteine. This effect varied, however, across the 20 trials (test of heterogeneity, P = 0.04). Although higher-quality trials demonstrated a stronger benefit for acetylcysteine in general, few reported important elements of study design, such as concealment of allocation, placebo-controls, or double-blinding. Heterogeneity was unexplained by subgroup analyses. Conclusion Acetylcysteine may reduce the incidence of contrast-related nephropathy, but this finding is reported inconsistently across currently available trials. High-quality, large clinical trials are needed before acetylcysteine use in this indication can be recommended universally.
Porting the 3D gyrokinetic particle-in-cell code GTC to the NEC SX-6 vector architecture: perspectives and challenges

Several years of optimization on the cache-based super-scalar architecture has made it more difficult to port the current version of the 3D particle-in-cell code GTC to the NEC SX-6 vector architecture. This paper explains the initial work that has been done to port this code to the SX-6 computer and to optimize the most time consuming parts. After a few modifications, single-processor results show a performance increase of 5.2 compared to the IBM SP Power3 processor, and 2.7 compared to the Power4.
Generalized latent inhibition in taste-aversion learning

Rats were preexposed, over 9 days, to either nine different flavors or a single flavor. Then they were given a novel saccharin-lithium pairing (controls were injected with isotonic saline). Generalized latent inhibition was demonstrated in the multiflavor group: Learned aversion to the novel saccharin CS was very transient. One-flavor subjects, in contrast, demonstrated a strong and lasting aversion to saccharin.
An interlaboratory comparison of source rock data

Abstract Organic matter in eight rock samples has been analyzed by nineteen laboratories and the results show that source rock data from any one laboratory cannot be directly compared to data from any other laboratory. A high degree of variability exists among the data reported by the nineteen participating laboratories, most of which can be explained by differences in the sample preparation steps and analytical procedures used in these laboratories. Differences also exist in the definition of basic units of measurement being reported. In order to make the data more comparable, standard rock samples and analytical methods should be developed and used by all laboratories. Until then, extreme caution must be used when comparing source rock data from different laboratories.
Co‐occurrence of DISH and HFI in the Terry Collection

Diffuse idiopathic skeletal hyperostosis (DISH) and hyperostosis frontalis internus (HFI) are both characterised by abnormal bone growth, a late age of onset, and an association with obesity, acromegaly and various metabolic disorders. In this study we examined the co-occurrence of DISH and HFI in a sample of 406 black and whites aged 40–102 years old from the Terry Collection, National Museum of Natural History, Smithsonian Institution. Fisher's exact tests showed the co-occurrence was significant for females. DISH was present in 19.6% of black and 29.6% of white females with HFI versus 4.76% and 2.38% of control females without HFI. A similar frequency of DISH was seen in males with HFI (20% black and 27.3% white), but this was not significantly different from the male controls without HFI (16.8% and 18.9%). The risk of developing DISH for females with HFI was nearly 8.78 times greater (CI = 2.56–30.1) than for females without HFI. Logistic regression of the female data showed HFI was a significant determinant (p = 0.001) of the presence of DISH but age was not (p = 0.744). We suggest that similar metabolic, genetic and environmental risk factors in the pathogenesis of the two conditions explain the observed comorbitity. Copyright © 2010 John Wiley & Sons, Ltd.
Does the early bird move the polls?: the use of the social media tool 'Twitter' by U.S. politicians and its impact on public opinion

Social media tools such as Twitter and Facebook have been hailed as politically transformative communications technologies, on the level of previous politically significant technological innovations, such as radio and television. In this paper we estimate the impact of the use of the social media tool 'Twitter' by American politicians on changes in public opinion of those politicians over time, and we find little evidence that the political use of Twitter has eitther a positive or negative impact on public opinion. We run simple regressions of changes in widely used U. S. public opinion polls, estimating the association between favorable impressions of selected politicians and the social media usage levels (number of 'Tweets') of those politicians. In order to get a reliable estimate, we ran the same regressions for public opinion polls conducted by three different companies (CNN/Opinion Research, Gallup, and ABC/Washington Post) and we find that the estimated coefficients are not significant for any of the tested opinion polls.
Photoaffinity cross-linking to the pituitary receptor for growth hormone-releasing factor

Photoaffinity cross-linking methods presented here demonstrate a 55-kilodalton (kDa) GH-releasing factor (GRF) receptor in ovine pituitary membranes and in cell lines expressing the cloned human pituitary receptor complementary DNA. Covalent cross-linking of photoprobe to this high affinity site is strongly competed by 1 nM GRF. Competition shows strong specificity for GRF over related peptides. Reduced cross-linking in the presence of guanosine 5'-O-(3-thiotriphosphate) suggests that this is a G-protein-coupled receptor. Detection of cross-linking to this receptor required detergent extraction to reduce high nonspecific binding of GRF photoprobe. Partial deglycosylation of the cross-linked receptor with neuraminidase caused a shift in apparent size to 52 kDa. Complete deglycosylation with N-glycosidase caused a shift to 45 kDa, demonstrating that this receptor is an N-linked glycoprotein and agreeing with the protein size and single glycosylation site predicted from the cloned complementary DNA sequence. These sizes differ from those found in previous reports which used chemical cross-linking to identify GRF receptor. This photoaffinity cross-linking method will facilitate studies of receptor function and tissue distribution. Photoaffinity cross-linking can also be used to map regions of the receptor molecule and bound GRF that are in close proximity.
A strategy for oscillatory drug release general scheme and simplified theory

Abstract A general scheme for achieving periodic pulsatile drug release through a membrane is described, with application to the delivery of hormonal agents and drugs that exhibit tolerance. The permeability of the membrane to a substrate of an enzymatic reaction is assumed to be dependent on the concentration of the product of that reaction in a manner that displays product inhibition. Under certain conditions this negative feedback control can lead to oscillations in membrane permeability to the substrate. If the membrane permeability to a drug is simultaneously affected, then this will lead to oscillatory drug release. The scheme is analogous to certain biochemical oscillators whose mechanisms are based on product inhibition. A simple model is introduced for illustration, and results of simulations based on the model are displayed. Sustained oscillations are achieved with certain conditions on the model parameters, while other sets of parameters lead to decaying oscillations. Parameter requirements for sustained oscillations are discussed qualitatively, with detailed theoretical analysis to appear in a subsequent publication.
Lax leaf maize: cell wall composition and nutritional value.

Forage nutritive value, which comprises traits such as digestibility, fibre, lignin and protein content, is an important criterion for maize (Zea mays L) harvested as silage. Lines with a characteristic phenotype (‘lax leaf’) could be useful sources of genes for improved nutritive value in maize. A study was conducted to characterise the cell wall composition of the lax leaf line. Lax leaf inbreds and inbreds representing ‘normal’ maize were evaluated for cell wall neutral sugars, uronic acids, Klason lignin and phenolic acids in five tissues from the ear node and the internode above it. Acid detergent fibre (ADF) and neutral detergent fibre (NDF) and 48 h in vitro true digestibility (IVTD) were predicted using near-infrared reflectance spectrophotometry (NIRS) calibrated with a subset of the scanned samples. Lax leaf inbred tissues had lower levels of ADF, NDF, lignin and xylose and were more digestible than tissues from the inbreds representing ‘normal’ maize. It was not known whether the lax leaf phenotype resulted from alterations in nutritive value traits or whether laxness and nutritive value traits are independent from one another. A second study was conducted to determine the nature of genetic control of the lax leaf character and to determine the genotypic relation between the lax leaf character and nutritive value. A recombinant inbred mapping population was developed from a cross between the lax leaf line and an inbred line with stiff upright leaves. Whole-plant samples from each recombinant inbred line were evaluated for ADF, NDF, acid detergent lignin (ADL) and IVTD of dry matter using NIRS. Laxness, measured by number of broken leaves, was associated with lower nutritive value in this population (genetic correlations 0.16–0.34), which was contrary to expectation. Amplified restriction fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers were used to identify linkage groups associated with the lax leaf character, digestibility and fibre content. Several linkage groups were associated with both the lax leaf character and nutritive value. Where these characters were associated with the same linkage group, the lax leaf parent allele was associated with greater laxness but reduced nutritive value. The lax leaf parent allele was associated with increased nutritive value in linkage groups unassociated with the lax leaf character. While the lax leaf line may be a good source for alleles for improved nutritive value, selection for laxness will not likely be accompanied by improvement in forage quality. © 2000 Society of Chemical Industry
Passivity based control of reaction diffusion systems: Application to the vapor recovery reactor in carbothermic aluminum production

Abstract We develop a passivity based controller for a reaction diffusion system. The model used in the simulation study describes the vapor recovery reactor used in carbothermic aluminum reduction. It takes into account, non-catalytic gas–solid reactions, the moving bed of solid particles and the shrinkage of the unreacted particle core. The reaction diffusion system is solved using the finite element method. We use passivity based control to adjust the carbon feed and the heat input to achieve the required conversion and maintain the temperature along the reactor. The efficiency of the reactor is determined by calculating the extent of vapor recovery and the conversion of carbon particles. The sensitivity of different parameters such as solid flow rate and column height based on the reactor performance is also determined. We show that the control scheme based on the inventory balances performs well under various operating conditions.
Protection against anthrax by needle-free mucosal immunization with human anthrax vaccine

Abstract Human vaccination with BioThrax™ requires six injections followed by annual boosters. This makes it difficult for the compliance of the immunization program and underscores the need for development of a new and optimized vaccination protocol. Current research aims to demonstrate the proof of concept to develop a needle-free mucosal immunization protocol using a murine anthrax model. A/J mice were immunized with BioThrax™ via an intranasal route. Sera, saliva, vaginal, and nasal washes were evaluated for protective antigen (PA) specific antibody responses by ELISA. Antigen-specific, antibody-secreting lymphocytes were measured by ELISPOT. Sera neutralization antibody titers were determined by in vitro anthrax lethal toxin (Letx) neutralization assay. Immunized animals were challenged by a lethal dose of Bacillus anthracis Sterne spores to determine the efficacy of the vaccination. Nasal mucosal immunization with BioThrax™ elicited robust serum and mucosal antibody responses against PA. The antigen specific antibodies neutralized anthrax Letx, as demonstrated by in vitro neutralization assays. Two doses of intranasal BioThrax™ were sufficient to completely protect A/J mice against challenge with 100 × LD 50 B. anthracis Sterne spores. The data suggests that intranasal administration may be an effective immunization modality for an improved immunization program against anthrax.
Bound states in the continuum from supersymmetric quantum mechanics.

Starting from a potential with a continuum of energy eigenstates, we show how the methods of supersymmetric quantum mechanics can be used to generate families of potentials with bound states in the continuum (BIC's). We also find the corresponding wave functions. Our method preserves the spectrum of the original potential except it adds these discrete BIC's at selected energies. Specifically, we compute and graph potentials which have bound states in the continuum starting from a null potential representing a free particle and from both the attractive and the repulsive Coulomb potentials.
Identification of cell types from action potential waveforms: cerebellar granule cells

We have recorded 404 single units extracellularly in the cerebellar cortex of the rat with tungsten microelectrodes. Waveforms of action potentials were analyzed in order to develop criteria for on-line identification of cell types. Two of the four most frequently recorded waveforms were simple and complex spikes from Purkinje cells. The other two originated from granule cells and glomeruli. Presumed granule cells showed biphasic action potentials with half-widths (0.78 +/- 0.14 ms, n = 51) broader than those of the simple spikes of Purkinje cells (0.22 +/- 0.06 ms, n = 54), whereas presumed glomerular potentials had complex action potentials with narrower half-widths (0.14 +/- 0.05 ms, n = 35). The mean inter-spike interval of presumed granule cells (333.3 +/- 195.4 ms, n = 53) was longer than that of Purkinje cells (47.3 +/- 31.8 ms, n = 59) and the presumed glomerular potentials (77.7 +/- 50.8 ms, n = 20). Results were virtually identical from 17 cerebellar units recorded extracellularly in the cat. Intracellular recording and staining of 20 granule cells with HRP-filled microelectrodes provided further support for our assessment. These results suggest that action potentials from granule cells may be identified on-line by waveform.
Do Social Class Gradients Explain Differences in American Adolescents' Health: An Exploration of the Relationships between Socioeconomic Status and Disease States in a Nationally Representative Sample of Youth

Do Social Class Gradients Explain Differences in American Adolescents' Health: An Exploration of the Relationships between Socioeconomic Status and Disease States in a Nationally Representative Sample of Youth
Construction of demountable hollow-cathode lamps for stimulating emission of organic compounds

Abstract A demountable hollow cathode has been constructed which provides emission spectra of organic compounds. The construction and operation of the hollow cathode is described. The emission spectra of organic and inorganic phosphates are illustrated and discussed.
Radical interception by carotenoids and effects on UV carcinogenesis

Studies employing time-resolved techniques have shown that beta-carotene, astaxanthin, and lycopene behave quite distinctly with respect to radical quenching and stability, lycopene being the least stable. These results are compatible with the relative effects of the various carotenoids on ultraviolet (UV)-mediated carcinogenesis in mice in which a statistically significant exacerbation by beta-carotene and astaxanthin, but not by lycopene, was observed. Interactions between these carotenoids and vitamin C and E radicals not only provide a chemical basis to explain the failure of beta-carotene to provide benefit in recent clinical trials but suggest that future carotenoid supplementation studies should proceed with caution until carotenoid interactions and radical repair mechanism(s) are elucidated.
Bifurcation theory of the critical liquid-gas interface

A new theory is presented to determine the structure of the intrinsic density profile of the liquidgas interface in the neighborhood of the critical point. In contrast to earlier theories, no use is made of scaling or homogeneity conjectures or of the Andrews-Thomson-van der Waals "loop" of the subcritical isotherm. A nonlinear integral equation is derived for the critical intrinsic density profile, and it is found that when the overall average density of the fluid is kept fixed and equal to its critical value and the temperature is allowed to vary, a nontrivial solution of the nonlinear integral equation, which described the intrinsic density profile, bifurcates at the critical point from the trivial solution which describes a spatially uniform fluid. It is shown that in the neighborhood of the critical point, this nontrivial solution has a scaling form which can be determined exactly. The asymptotic behavior of this nontrivial solution can also be calculated exactly: The wings of the intrinsic density profile decay exponentially with an exponent proportional to the inverse correlation length of the spontaneous density fluctuations in either bulk phase. These results confirm the conjectures of Widom.
The 40-residue insertion in Vibrio cholerae FadR facilitates binding of an additional fatty acyl-CoA ligand

FadR is a regulator of fatty acid metabolism in bacteria, and contains a binding site for acyl-CoA. Here, Shi et al. present a structure of V. cholerae FadR and show that a unique C-terminal extension comprises a second acyl-CoA binding site, perhaps rendering V. cholerae FadR a more efficient regulator.
A comparative immunologic analysis of several murine strains with autoimmune manifestations

Abstract The genetic autoimmune disease (lupus-like) in mice of several strains (NZB, NZB × W, MRL 1 , MRL n , BXSB) has been analyzed comprehensively. Comparison of the histoimmunopathologic, serologic, and cellular characteristics of these mice reveals several pathogenic common denominators but no obvious etiologic factors in common. In all kinds of autoimmune mice studied, the lupus-like syndrome consists of a fatal immune complex glomerulonephritis, thymic atrophy, and lymphoid hyperplasia that varies in degree. The lymphoid hyperplasia is most prominent in MRL 1 mice and it is of T-cell origin. MRL 1 mice, in addition, may exhibit arteritis and arthritis. Serologically, all SLE mice have abnormally elevated serum Ig levels, antinuclear antibodies, anti-ds- and ssDNA antibodies, and anti-hapten antibodies. Some of the MRL 1 mice, in addition to the above antibodies, develop antibodies to Sm ( MRL 1 and MRL n ) and antiglobulins ( MRL 1 ). Natural thymocytotoxic antibodies and anti-erythrocyte antibodies are predominantly found in NZB and NZB × W mice. With advanced age and disease all lupus mice have depressed complement levels and circulating immune complexes. Some of these complexes in all lupus mice are composed of retroviral gp70-anti-gp70 antibodies, whereas MRL 1 mice, in addition, contain circulating IgG-IgG RF complexes. Characterizing the various recognized lymphoid cell surface markers, one notes that each strain of lupus mice has some variation from the normal distribution, but in no two of these strains are the abnormalities the same. The B cells of these mice seem advanced in maturity, whereas the developmental isotype diversity is normal in all of them. NZB and NZB × W mice are characterized by a nonspecific early B-cell hyperactivity but it is not known if this activity is responsible for their subsequent specific autoantibody production. The proliferating T cells of older MRL 1 mice seem to exert excessive helper activity on syngeneic B cells. Both antigen-specific and antigen-nonspecific Con A-induced suppression are within normal limits in all lupus mice. Although transfer studies have shown that the basic defect is associated with the lymphoid system, from our work and that of others it appears that the abnormalities in these mice are polygenic and different from one strain to another. Thus, murine lupus as a syndrome can be the result of many different abnormalities which eventuate in B-cell hyperactivity and involvement of a number of the available endogenous antigens in a systemic immune complex disease which is responsible for the “characteristic” clinical picture of systemic lupus erythematosus.
Spectroscopic Studies of the Interaction of Methyl Orange with Cationic Alkyltrimethylammonium Bromide Surfactants

Abstract The spectral signature of the azo dye methyl orange (MO) exhibits a considerable sensitivity to the polarity of the dye's environment. We have used this dependence of absorption wavelength on microenvironment to investigate the 1:1 ion pair complexes formed from electrostatic interaction of a series of cationic alkyltrimethylammonium bromide (C n TAB) detergents with the anionic organic probe in aqueous solution. At surfactant concentrations far below the critical micelle concentration, MO shifts in absorbance λ max from 462 nm in aqueous solution to 367–377 nm upon complex formation. Nonlinear least-squares deconvolution of the absorbance spectra reveals a previously unreported significant blue shift in λ max with increasing surfactant alkyl chain length. Our time-dependent spectrophotometric studies of the MO–C n TAB complex systems reveal, also for the first time, that a subsequent spectral shift to shorter wavelengths (λ max = 348–350 nm) occurs for those alkyl chain lengths greater than n = 14. These observations are consistent with an aggregation of the surfactant–dye pair after initial complex formation. Increased hydrophobic interaction of the azo ring of the probe with additional neighboring surfactant alkyl chains to achieve a final equilibrium state is hypothesized to account for the MO absorbance spectral shift.
TU-G-134-08: Short Term Reproducibility in Apparent Diffusion Coefficient for Diffusion Weighted MRI of the Prostate

Purpose: In this study we evaluate the short term reproducibility of Diffusion Weighted MR Imaging (DW‐MRI) of the prostate by analyzing variation in ADC maps. Methods: 14 patients with biopsy proven prostate cancer were evaluated under an IRB‐approved protocol. Each patient underwent two, identical DW‐MRI scans with the patient remaining on the table and only automatic shimming with tuning and matching between acquisitions. ADC maps were generated using a least squares fit. The prostate and ROIs within cancer lesions were delineated on each scan per patient by two radiologists using the b‐0 images and a rigid local registration was performed using multiple radiologist‐defined landmarks throughout the prostate on each of the two scans. The absolute and percentage differences in ADC per voxel were calculated. For each patient the prostate was divided into equally spaced sextants and the voxel‐based variation in each sextant was compared. Results: The absolute difference in ADC per voxel within the prostate ranged from 1.13×10−9 to 1.91×10∼−3 mm2/sec (mean and standard deviation percentage difference 10.35% ± 10.91%). The largest variation is seen in the posterior apex (mean 11.46%, median 8.02%, standard deviation 11.73%) although we were not able to demonstrate statistical significance in the difference in variation between sextants. Cancer ROIs showed a mean, median and standard deviation in ADC difference of 13.36%, 6.90% and 14.48%, respectively. Conclusion: DW‐MRI has strong potential to become a powerful quantitative imaging biomarker for prostate cancer. It is imperative to know the reproducibility of the imaging method when utilizing DW‐MRI in the clinic or developing new approaches for its use. Our data demonstrates that ADC variation within the prostate is modest, on the order of 10%, similar to other abdominal tissues, and the variation appears to be highest in the apex region of the prostate.
The effects on stressful organizational conditions on salesperson work motivation

This paper examines how organizational stress may contribute to intrinsic and extrinsic dimensions of salesperson work motivation. Hypotheses generated on the basis of sales management and organizational stress literature are tested using data gathered from an insurance sales population. Results indicate that excessive role stress may produce a significant adverse impact on salespersons' intrinsic and extrinsic work motivation. Research findings are discussed from a managerial perspective.
Discharge disposition from model spinal cord injury care system rehabilitation programs.

Abstract Objective: To identify and quantify factors associated with discharge to a nursing home for people with spinal cord injuries. Design: Case control within a cohort of spinal cord injured persons. Setting: Model spinal cord injury care systems throughout the United States. Patients: A total 16,633 patients consecutively discharged alive between 1973 and 1996 who were admitted to the model system within 1 year of injury, who were both injured in and resided in the catchment area of the model system, and who were discharged to either a nursing home or a community residence. Main Outcome Measure: Discharge disposition. Results: Overall, 4.3% of patients were discharged to a nursing home. Factors that were significantly associated ( p Conclusions: Knowing the probability of nursing home placement can assist in evaluating the success of a rehabilitation program by allowing adjustment for case-mix differences across facilities.
A language of precision.

At a recent meeting of psychiatric mental-health nurses, the effect of the Information Technology (IT) revolution on the specialty was examined. The speaker, a leader in the field of integrating IT...
YZGD from Paenibacillus thiaminolyticus, a pyridoxal phosphatase of the HAD (haloacid dehalogenase) superfamily and a versatile member of the Nudix (nucleoside diphosphate x) hydrolase superfamily

YZGD from Paenibacillus thiaminolyticus is a novel bifunctional enzyme with both PLPase (pyridoxal phosphatase) and Nudix (nucleoside diphosphate x) hydrolase activities. The PLPase activity is catalysed by the HAD (haloacid dehalogenase) superfamily motif of the enzyme, and the Nudix hydrolase activity is catalysed by the conserved Nudix signature sequence within a separate portion of the enzyme, as confirmed by site-directed mutagenesis. YZGD's phosphatase activity is very specific, with pyridoxal phosphate being the only natural substrate, while YZGD's Nudix activity is just the opposite, with YZGD being the most versatile Nudix hydrolase characterized to date. YZGD's Nudix substrates include the CDP-alcohols (CDP-ethanol, CDP-choline and CDP-glycerol), the ADP-coenzymes (NADH, NAD and FAD), ADP-sugars, TDP-glucose and, to a lesser extent, UDP- and GDP-sugars. Regardless of the Nudix substrate, one of the products is always a nucleoside monophosphate, suggesting a role in nucleotide salvage. Both the PLPase and Nudix hydrolase activities require a bivalent metal cation, but while PLPase activity is supported by Co2+, Mg2+, Zn2+ and Mn2+, the Nudix hydrolase activity is Mn2+-specific. YZGD's phosphatase activity is optimal at an acidic pH (pH 5), while YZGD's Nudix activities are optimal at an alkaline pH (pH 8.5). YZGD is the first enzyme reported to be a member of both the HAD and Nudix hydrolase superfamilies, the first PLPase to be recognized as a member of the HAD superfamily and the first Nudix hydrolase capable of hydrolysing ADP-x, CDP-x and TDP-x substrates with comparable substrate specificity.
EFFECT OF MERCURY VAPOR EXPOSURE ON METALLOTHIONEIN AND GLUTATHIONE S -TRANSFERASE GENE EXPRESSION IN THE KIDNEY OF NONPREGNANT, PREGNANT, AND NEONATAL RATS

Elemental mercury (Hg(0)) is a ubiquitous toxic pollutant. Exposure to Hg(0) vapor typically is by inhalation, and the kidney is the primary target organ. Glutathione (GSH) and metallothionein (MT) appear to mitigate mercury toxicity. However, little is known about GSH or MT regulation after Hg(0) vapor exposure, particularly during pregnancy, a time of high sensitivity to most metals. Thus, this study sought to determine renal mercury accumulation and MT- and GSH-related gene expression following Hg(0) vapor exposure in nonpregnant, pregnant, and neonatal rats exposed in utero. Groups (n = 5) of pregnant rats (Long-Evans) were exposed to Hg(0) vapor (4 mg/m(3)) or air (control) for 2 h/d from gestational day (GD) 6 to 15, and kidneys from dams and pups were removed at various times during and after the onset of exposure. For comparative purposes, nonpregnant female rats were exposed to Hg(0) for 10 d under the same conditions. Renal mercury, MT protein, and GST activity were assayed by standard analytical techniques. Western blot analysis was also performed using antibodies against MT and GST-pi. GSH-related gene expression was studied by cDNA microarray. Hg(0) vapor exposure produced renal accumulation of mercury in nonpregnant, pregnant, and neonatal rats. However, the transplacentally exposed neonates accumulated approximately 1000-fold less mercury than adults. Hg(0) vapor exposure produced a time-dependent increase in renal MT protein in nonpregnant and pregnant rats, but not in neonatal rats. Maximum MT increases were observed on d 10 (fivefold) in nonpregnant and GD 15 (threefold) in pregnant rats. Activation of the MT gene by Hg(0) was confirmed at the translational level by Western blot analysis and at the transcriptional level by Northern blot analysis. Microarray analysis revealed a significant upregulation in the renal expression of the GST-pi, GST-Ya, and microsomal GST and GST5-5 genes in nonpregnant and pregnant rats. Western blot and enzyme assay confirmed the upregulation of GST genes after Hg(0) exposure. Thus, in response to Hg(0) vapor exposure, the expression of the MT gene and various GST genes is activated in nonpregnant and pregnant rats. Activation of these genes could be part of a defensive response directed at decreasing renal mercury toxicity, and may help divert the metal away from the fetus.
A generalized weight for linear codes and a Witt-MacWilliams theorem

Let F be a finite field, H a subgroup of F∗ of index ν, and α1,…, αν coset representatives. For each n-tuple u = (u1,…, un) ϵ Fn define WH(u) = (w1(u),…, wν(u)), where wm(u) = #{ui: ui ϵ αmH}. An H-monomial map on Fn is an automorphism of Fn whose matrix with respect to the co-ordinate basis is of the form P · D, where P is a permutation matrix and D is a diagonal matrix with non-zero entries from H. Suppose C is an (n, k) code over F (that is, a k-dimensional subspace of Fn) and that ϕ: C → Fn is an injective homomorphism which preserves WH in the sense that WH(ϕ(u)) = WH(u) for all u ϵ C. We prove that ϕ may be extended to an H-monomial map on Fn. This generalization of a theorem of MacWilliams on the (Hamming) equivalence of codes may be considered an analogue of the Witt theorem of metric vector space theory.
Book Review: An Author's Response

In his generous review of my book, The Garden of the Eight Paradises … (Iranian Studies, volume 39, number 3, September 2006), Professor Robert McChesney raises some important issues—and omits othe...
Climbing the Crystal Stair: Values, Affirmative Action and Minority Faculty.

Efforts to increase the number of minority faculty in predominantly white colleges and universities in the United States have been less successful than is commonly supposed. Significant barriers to minority access and retention remain. This paper examines the supply of, and demand for, minority faculty, stressing the limiting role of institutionalized values—merit and autonomy. I look at difficulties in affirmative action, the major proposed remedy to problems of supply and demand, and the problems of post-compliance discrimination. Racial inequality in academic careers is likely to persist as long as these barriers, and the conditions which produce them, remain unchanged.
Solubility of gold nanoparticles as a function of ligand shell and alkane solvent

The solubility of ca. 5.0 nm gold nanoparticles was studied systematically as a function of ligand shell and solvent. The ligands were octane-, decane-, dodecane- and hexadecanethiols; the solvents were the n-alkanes from hexane to hexadecane and toluene. Supernatant concentrations in equilibrium with precipitated superclusters of nanoparticles were measured at room temperature (23 °C) with UV-Vis spectrophotometry. The solubility of nanoparticles ligated with decane- and dodecanethiol was greatest in n-decane and n-dodecane, respectively. In contrast, the solubility of nanoparticles ligated with octane- and hexadecanethiol showed decreasing solubility with increasing solvent chain length. In addition the solubility of the octanethiol ligated system showed a nonmonotonic solvent carbon number functionality with even numbered solvents being better solvents than neighboring odd numbered solvents.
Amino acids that specify structure through hydrophobic clustering and histidine-aromatic interactions lead to biologically active peptidomimetics

Acyclic beta-sheet structure can be nucleated in heptapeptides when the 4-(2-aminoethyl)-6-dibenzofuranpropanoic acid residue (1) is flanked in sequence by two His residues, a His residue and a hydrophobic residue or by two hydrophobic residues. Acyclic beta-sheet peptidomimetics having an appropriate sequence have sufficient structural integrity to exhibit antimicrobial activity equivalent to that of gramicidin S.
Economics of General-Purpose Assembly Robots

Summary A study of the comparative economics of various automatic assembly systems using general-purpose assembly robots is described. In the study, use is made of a “typical” candidate assembly whose profile is obtained from statistical analysis of actual products submitted by interested companies. It is shown that the choice of assembly system and the various parts presentation methods depends on three main factors, namely: the annual production volume per shift, the number of parts in the product and the equipment payback period.
Effects of secondary particles on the total dose and the displacement damage in space proton environments

MCNPX, a powerful Monte Carlo charged particle transport code, is introduced in this paper for space-radiation effect applications. By using MCNPX version 2.1.5, the enhancement of the total dose and the displacement damage due to secondary particles generated by the protons in the typical space radiation environments was assessed, then the results were compared to those obtained by the continuous slowing down approximation (CSDA) method. The comparison showed that the effects of the secondary particles were up to +7% for the total dose and up to +25% for the displacement damage when compared to the respective CSDA results in heavy shielding applications where trapped and solar protons dominate. Also presented in this paper is a method to compute the neutron/proton displacement cross sections by using MCNPX. The cross sections obtained show an excellent agreement with previously published values.
Early Gene Expression Associated with Regeneration Is Intact after Massive Hepatectomy in Rats

Abstract Background.Liver regeneration occurs promptly after partial hepatectomy, although the factors regulating this response have not been fully clarified. Molecular events in the regenerative response have been widely characterized after 70% hepatectomy which represents a model of “normal” liver regeneration in rats. More extensive resection results in hepatic failure which has been attributed to a critical loss of hepatic mass. It is not known whether the pattern of genes expressed early in regeneration remains intact after lethal hepatectomy. We hypothesize that the increased expression of selected early response genes remains intact after massive hepatectomy. The aim of this study was to compare the expression of selected genes after 70 and 85% hepatectomy. Materials and methods.One hundred ten Wistar rats were divided into three groups: control group (sham laparotomy) (n= 30), 70% hepatectomy group (n= 40), and 85% hepatectomy group (n= 40). Animals were sacrificed at intervals. Livers were excised and divided into four equal specimens, snap frozen, and stored at −70°C. RNA was extracted by standard methods and preparations were probed for protooncogenes, c-myc, c-fos, and for hepatocyte growth factor, and its receptor, c-met. After overnight exposure of autoradiographs, quantification was accomplished by densitometry of RNA slot blots. Results.After 70% hepatectomy, peaks of maximal expression for both c-myc and c-met were observed after 1 and 12 h. For c-fos, peak of maximal expression was observed at 6 h. For HGF, peak was observed between 12 h and Day 2. After 85% hepatectomy, rats demonstrated similar patterns including peak expression of c-myc at 1 h, but altered peak at 12 h. For c-met, the same pattern was observed between 1 and 12 h. For HGF, two peaks were noted: a first peak at 1 h, and a peak similar to the peak observed after 70% hepatectomy at 12 h. Conclusions.These results suggest that early molecular events which are part of the regenerative response are largely intact after 85% lethal hepatectomy. We propose that liver dysfunction and the failure of regeneration observed after 85% hepatectomy is not due to alteration of early signaling. Further study will be required to define failure of the regeneration program in this model.