cssi/SciSciGPT-SciSciNet huggingface dataset:
Adrenal cortical function in homozygous familial hypercholesterolemia

Abstract The biosynthesis of adrenal corticosteroids requires a supply of cholesterol that can be derived from both local synthesis and uptake of plasma lipoproteins. Recent studies have provided evidence that receptor-mediated uptake of low density lipoproteins provides an important source of cholesterol for corticosteroid synthesis by human adrenocortical cells that are grown in tissue culture. In the present study we have examined parameters of adrenocortical function in three patients with homozygous familial hypercholesterolemia (two receptor negative, one receptor defective) to assess whether a decreased number of LDL receptors, measured in vitro, influences in vivo corticosteroid production under basal conditions and in response to prolonged stimulation with ACTH. Basal adrenocortical function (assessed by the serum concentrations of cortisol and ACTH plus urinary excretion of 17 OHCS, 17 KS, and urine-free cortisol) was normal in all three patients. Stimulation with intravenous ACTH resulted in rapid increases in the serum concentrations of cortisol in all patients. Plateau concentrations of cortisol during prolonged ACTH stimulation were lower in the two receptor-negative patients (36 to 41 μg/dl) but all subjects had at least a threefold increase over basal values. Excretion of urine-free cortisol was reduced in both receptor-negative patients (33% to 36% of controls); this was paralleled by decreased excretion of 17 KS in both patients and of 17 OHCS in one patient. Urine-free cortisol excretion was reduced in the receptor-defective patient (57% of controls), but excretion of 17 OHCS and 17 KS was not. The results suggest that patients with homozygous familial hypercholesterolemia have a mild impairment in delivery of cholesterol to the adrenal cortex during maximal stimulation of corticosteroid production but that the disease does not impair corticosteroid synthesis in the basal state.
Oxidation Behavior of Rare‐Earth Disilicate–Silicon Nitride Ceramics

In this paper, the oxidation behavior and microstructure of the oxidized surfaces of RE[sub 2]Si[sub 2]O[sub 7]-Si[sub 3]N[sub 4] ceramics are investigated. The high oxidation resistance of these materials at 1400[degrees]C is attributed to the minimization of amorphous phases via devitrification to disilicates that are in equilibrium with SiO[sub 2], the oxidation product of Si[sub 3]N[sub 4]. Crystals of RE[sub 2]Si[sub 2]O[sub 7] grew out of the surfaces silicate in preferred orientations that were dictated by crystal structure. The morphology of the microstructure of the oxidized surfaces was shown to be partially dependent on the concentration of impurities; the presence of Ca was found to coincide with the growth of Gd[sub 2]Si[sub 2]O[sub 7] and Dy[sub 2]Si[sub 2]O[sub 7] crystals with high aspect ratios.
Effective Instruction and College Student Persistence: Some New Evidence.

The research presented here indicates that exposure to organized and clear classroom instruction may have positive net effects on the probability of returning to an institution for the second year of college.
Melatonin reduces ischemia/reperfusion-induced superoxide generation in arterial wall and cell death in skeletal muscle

The purpose of this study was to determine the effect of melatonin on superoxide generation in arterial wall at an early phase of reperfusion and on endothelial dysfunction of microvasculature and cell viability of cremaster muscle at late phase of reperfusion (24 hr) after prolonged ischemia. Bilateral vascular pedicles which supply blood flow to the cremaster muscle were exposed. After surgical preparation, microvascular clamps were applied on the right iliac, femoral and spermatic arteries to create 4 hr of ischemia in both feeding vessels and the unexposed cremaster muscle. The vascular clamping was omitted on the left iliac, femoral and spermatic arteries and served as an internal control. Melatonin or Vehicle was via by intravenous injection at 10 min prior to reperfusion and 10 min after reperfusion. In the first experiment, the vascular pedicle was harvested after reperfusion to measure superoxide generation in real time by lucigenin-derived chemiluminescence. In the second experiment, endothelial-dependent and -independent vasodilatation was examined in the terminal arteriole of cremaster muscle which was then harvested to examine cell viability by WST-1 assay on day 2. Superoxide generation in arterial wall peaked at first 5-min of reperfusion and declined to near baseline after 60 min of reperfusion. Melatonin treatment significantly reduced superoxide generation in arterial walls and improved cell viability in cremaster muscles. Melatonin treatment also significantly reduced microvascular endothelial dysfunction which was still observable in the microcirculation of cremaster muscle after 24 hr of reperfusion. Melatonin reduces superoxide generation in the early phase of reperfusion resulting in attenuating endothelial dysfunction and muscle cell death in the late phase of reperfusion.
Monocytes, alcohol use, and altered immunity

The immunomodulatory capacity of acute, moderate alcohol consumption was investigated in this study in nonalcoholic volunteers after 2 ml of vodka/kg body weight of alcohol consumption. There was a significant, transient increase in interleukin-12 and interferon-gamma (IFNgamma) levels in whole blood samples collected 4 hr after alcohol consumption in response to an ex vivo bacterial challenge with lipopolysaccharide (p < 0.02). However, decreased IFNgamma levels were produced by mononuclear cells collected later after alcohol consumption (16 hr), suggesting that acute alcohol consumption has a biphasic effect on IFNgamma inducibility. Furthermore, isolated blood monocytes collected 16 hr after alcohol consumption showed significantly decreased IL-1beta production in response to subsequent bacterial stimulation, implying that in vivo alcohol consumption affects monocyte-derived inflammatory cytokine production. These results demonstrate that even acute, moderate alcohol consumption has a modulating capacity on immune functions that may contribute to decreased immunity and host defense.
Mothers and daughters: perceived and real differences in sexual values.

In much previous research, parents and their late adolescent children have generally been shown to differ greatly in their attitudes towards premarital sexual behavior. Rather uniformly, adolescents have been found to express higher "premarital permissiveness" than adults, when permissiveness is defined as viewing premarital sexual behavior as morally acceptable (Reiss, 1967; Bell & Buerkle, 1961, 1962). For example, Bell & Buerkle (1961) found that 89% of a group of mothers but only 555? of their daughters felt it was "very important" to be a virgin at marriage. This difference between adolescents and adults becomes more marked if one considers the degree of emotional intimacy or interpersonal commitment involved in a premarital relationship. In Reiss's (1967) extensive study of premarital sexual permissiveness, adults and adolescents differed only slightly in their values regarding sexual behavior in a premarital relationship characterized as involving "no affection" or "strong affection." In relationships characterized by "love" or by being "engaged to be married," there was much greater disagreement between parents and children. Another example of the effect of the intensity of the interpersonal relationship in producing large parent-child differences in premarital permissiveness is provided by Bell 8c Buerkle's (1961) data that 83% of mothers and only 35% of daughters feel that intercourse during engagement is "very wrong." These data make it appear that there is indeed a real "generation
Relaxation calculation of the electrostatic properties of compensated Penning traps with hyperbolic electrodes

Spectacular accuracies have been achieved with single elementary particles trapped in hyperbolic Penning traps, but only after anharmonicities have been tuned out of these traps by varying the potential of extra compensation electrodes introduced into the traps. The relaxation calculation reported here is the first theoretical study of the electrostatic properties of such compensated Penning traps. Enough computations have been completed to clarify the basic physics involved in anharmonicity compensation and to provide useful, quantitative information for experiments in progress (especially for testing of anharmonicity systematics). The clearer picture of anharmonicity compensation which emerges suggests that the design of existing Penning traps could be significantly improved. An optimal electrode configuration is proposed which, in principle, makes the harmonic oscillation frequency of a trapped particle independent of changes in the compensation potential.
Platelet transfusion therapy in acute leukemia: Lack of effect of splenomegaly on transfusion requirements and risk of hemorrhage

Platelet transfusions are an important supportive measure during treatment for acute nonlymphocytic leukemia (ANLL). The presence of splenomegaly may produce decreased posttransfusion platelet increments leading some to recommend an increased dose of platelets per transfusion in this situation. Forty-nine newly diagnosed patients with ANLL were evaluated during 1980 and 1981, and 24% had palpable splenomegaly. Although treated with usual doses of platelets per transfusion, there was no detectable statistical increase in transfusion requirement or incidence of hemorrhage in patients with splenomegaly. Experimental evidence indicates that the splenic platelet pool enlarges with splenomegaly, but the life span of circulating platelets is not significantly changed. Furthermore, the splenic platelet pool is in dynamic equilibrium with the circulating platelet pool thus allowing these platelets to participate in hemostasis. Although posttransfusion increment in platelet count may be less, it appears that platelet transfusion therapy need not be altered solely because of splenomegaly.
Preliminary characterization of a variant co-binding heme protein from Nitrosomonas.

Abstract A soluble pigment with a major absorption peak at 463 nm in the reduced-minus-oxidized absorption spectrum was found in the supernatant fraction resulting from centrifugation of extracts of Nitrosomonas europaea. It was purified by repeated ammonium sulfate fractionation, chromatography on Amberlite CG-50 and gel filtration with Sephadex G-100. The purified protein was essentially free of contaminating a-, b-, c- or o-type cytochromes but contained 30% RNA. Absorbance maxima of absolute spectra were as follows: oxidized, 435 nm with a broad shoulder at 490–580 nm; reduced, 460 nm; reduced-plus-CO, 446 nm. Small bands at 535 nm and 565 nm were seen in reduced-minus-oxidized spectra. The pigment was designated P-460. The prosthetic group was not extracted with acidic acetone. The ferrohemochrome of the pigment had absorption maxima at 433 nm, 530 nm and 560 nm. P-460 was slowly autooxidized but deteriorated to a form which did not absorb at 460 nm. Aging or treatment with cholate or ethanol caused conversion of the reduced or reduced-plus-CO P-460 to a 423-nm-absorbing form. Hydrazine, hydroxylamine, or cyanide caused a 7–12-nm red shift in the oxidized form of P-460 and a blue shift in the reduced form. Increasing pH in the range 6.5 to 8.5 caused a decrease in height of the 460-nm or 446-nm peaks of the reduced or reduced-plus-CO spectra, respectively, and a concomitant increase in the broad peak in the 530 region. Based on the preliminary spectral properties presented here, P-460 of Nitrosomonas appears to be a new heme protein.
Lead neurotoxicity: From exposure to molecular effects

The effects of lead (Pb(2+)) on human health have been recognized since antiquity. However, it was not until the 1970s that seminal epidemiological studies provided evidence on the effects of Pb(2+) intoxication on cognitive function in children. During the last two decades, advances in behavioral, cellular and molecular neuroscience have provided the necessary experimental tools to begin deciphering the many and complex effects of Pb(2+) on neuronal processes and cell types that are essential for synaptic plasticity and learning and memory in the mammalian brain. In this review, we concentrate our efforts on the effects of Pb(2+) on glutamatergic synapses and specifically on the accumulating evidence that the N-methyl-D-aspartate type of excitatory amino acid receptor (NMDAR) is a direct target for Pb(2+) effects in the brain. Our working hypothesis is that disruption of the ontogenetically defined pattern of NMDAR subunit expression and NMDAR-mediated calcium signaling in glutamatergic synapses is a principal mechanism for Pb(2+)-induced deficits in synaptic plasticity and in learning and memory documented in animal models of Pb(2+) neurotoxicity. We provide an introductory overview of the magnitude of the problem of Pb(2+) exposure to bring forth the reality that childhood Pb(2+) intoxication remains a major public health problem not only in the United States but worldwide. Finally, the latest research offers some hope that the devastating effects of childhood Pb(2+) intoxication in a child's ability to learn may be reversible if the appropriate stimulatory environment is provided.
Mycarditis and cardiotropic viral infection associated with severe left ventricular dysfunction in late-stage infection with human immunodeficiency virus

Abstract Objectives. The purpose of this study was to characterize the histologic and immunopathologic results of 37 endomyocardial biopsy samples from patients infected with human immunodeficiency virus type 1 (HIV-1) who were evaluated for unexplained global left ventricular dysfunction. Background. Recent studies have identified a growing number of patients infected with HIV-1 who develop unexplained left ventricular dysfunction and congestive heart failure. Myocarditis has been confirmed at autopsy in small numbers of such patients, although a pathogenic opportunistic infectious agent can rarely be identified. Methods. All patients had moderate to severe global left ventricular hypokinesia on two-dimensional echocardiography. Endomyocardial biopsy samples were evaluated by standard histologic studies, immunoperoxidase staining and in situ hybridization for cytomegalovirus and HIV-1 gene sequences. Results. Twenty-eight patients presented with New York Heart Association functional class III or IV congestive heart failure. Four patients had myocarditis secondary to known etiologies (opportunistic infection n = 2; drug-induced hypersensitivity myocarditis n = 2). Of the remaining 33 samples, 17 (51%) showed histologic evidence of idiopathic active or borderline myocarditis. Immunohistologic findings revealed induced expression of major histocompatibility class I antigen on myocytes and increased numbers of infiltrating CD8+T lymphocytes. Specific hybridization within myocytes was observed in 5 of 33 samples with the HIV-1 antisense riboprobe and in 16 of 33 samples with the cytomegalovirus immediate early (IE-2) antisense riboprobe. All but one patient with specific myocyte hybridization presented with congestive heart failure; all patients had myocarditis and CD4+cell counts Conclusions. This study demonstrates that cardiotropic virus infection and myocarditis may be important in the pathogenesis of symptomatic HIV-associated cardiomyopathy.
Evidence for the Rate of the Final Step in the Bacteriorhodopsin Photocycle Being Controlled by the Proton Release Group: R134H Mutant†

Light absorbed by bacteriorhodopsin (bR) leads to a proton being released at the extracellular surface of the purple membrane. Structural studies as well as studies of mutants of bR indicate that several groups form a pathway for proton transfer from the Schiff base to the extracellular surface. These groups include D85, R82, E204, E194, and water molecules. Other residues may be important in tuning the initial state pK(a) values of these groups and in mediating light-induced changes of the pK(a) values. A potentially important residue is R134: it is located close to E194 and might interact electrostatically to affect the pK(a) of E194 and light-induced proton release. In this study we investigated effects of the substitution of R134 with a histidine on light-induced proton release and on the photocycle transitions associated with proton transfer. By measuring the light-induced absorption changes versus pH, we found that the R134H mutation results in an increase in the pK(a) of the proton release group in both the M (0.6 pK unit) and O (0.7 pK unit) intermediate states. This indicates the importance of R134 in tuning the pK(a) of the group that, at neutral and high pH, releases the proton upon M formation (fast proton release) and that, at low pH, releases the proton simultaneously with O decay (slow proton release). The higher pK(a) of the proton release group found in R134H correlates with the slowing of the rate of the O --> bR transition at low pH and probably is the cause of this slowing. The pH dependence of the fraction of the O intermediate is altered in R134H compared to the WT but is similar to that in the E194D mutant: a very small amount of O is present at neutral pH, but the fraction of O increases greatly upon decreasing the pH. These results provide further support for the hypothesis that the O --> bR transition is controlled by the rate of deprotonation of the proton release group. These data also provide further evidence for the importance of the R134-E194 interaction in modulating proton release from D85 after light has led to its being protonated.
A Comparison of Wet Deposition Collectors at a Coastal Rural Site

Atmospheric deposition occurs in a variety of forms and is crucial for the evaluation of nutrient budgets, critical loads, and pollution inputs across space and time. Atmospheric wet deposition is typically quantified by analyzing the chemistry of precipitation that is collected in some type of container with a lid that opens in response to precipitation. However, collectors can vary in shape as well as in the sensor that signals when precipitation is occurring. Here, we compare the collectors made by Aerochem Metrics and N-CON Systems Company Inc. The former has been widely used for several decades, while the latter is relatively new and has been used in a variety of configurations depending on the solute of interest. Event-based samples were collected from August 2007 to October 2008 and analyzed for nitrate, ammonium, sulfate, chloride, and dissolved organic carbon (DOC). A variety of approaches were used to assess the comparability of the two collectors. Regressions of concentration versus concentration from the two collectors were strong, and the slope did not differ from 1 for nitrate, ammonium, or sulfate. The median concentrations of nitrate, ammonium, and sulfate were, however, significantly higher in the N-CON collector, while there were no overall differences between collectors for chloride or DOC. Although we have observed some statistically significant differences between solute concentrations of samples collected from the two collectors, our mixed results suggest that these differences are relatively small.
Predicting the structure of apolipoprotein A-I in reconstituted high-density lipoprotein disks

In reconstituted high-density lipoproteins, apolipoprotein A-I and phosphatidylcholines combine to form disks in which the amphipathic alpha-helices of apolipoprotein A-1 bind to the edge of a lipid bilayer core, shielding the hydrophic lipid tails from the aqueous environment. We have employed experimental data, sequence analysis, and molecular modeling to construct an atomic model of such a reconstituted high-density lipoprotein disk consisting of two apolipoprotein A-I proteins and 160 palmitoyloleoylphosphatidylcholine lipids. The initial globular domain (1–47) of apolipoprotein A-I was excluded from the model, which was hydrated with an 8-A shell of water molecules. Molecular dynamics and simulated annealing were used to test the stability of the model. Both head-to-tail and head-to-head forms of a reconstituted high-density lipoprotein were simulated. In our simulations the protein contained and adhered to the lipid bilayer while providing good coverage of the lipid tails.
The Righi-Leduc effect in the mixed state of a pure type-II superconductor

Measurements of the Righi-Leduc effect, the thermal analog of the Hall effect, in the mixed state of pure niobium are reported. The transverse temperature gradient is approximately field independent aboveH c1. The thermal Hall angle has a strong field dependence nearH c2. Comparison is made between these data and existing Hall effect measurements in the mixed state.
Observation of photodetector nonlinearities

A heterodyne technique is used to characterise the nonlinear response behaviour of microwave pin photodetectors in terms of 3 dB bandwidth reduction and signal distortion of the sinusoidal input/output. Bandwidth reductions from 20 to 2.5 GHz (at 1.6mW) are observed.
Put-call parity revisited: intradaily tests in the foreign currency options market

Abstract We test exchange-traded (PHLX) German mark options for conformance to put-call parity (PCP). Puts and calls are matched to the nearest minute, and the relative impact of competing spot exchange rate sources (Reuters vs. Telerate) is assessed. We find that PCP usually holds (roughly 96% of put-call pairs), with the exception of a notable incident in the European options pits. In those instances in which PCP is violated, we find sharp intradaily and intraweekly seasonalities for American options, with disproportionate PCP violations occurring during the relatively light trading periods in early evening and on Fridays. We also conclude that the Telerate prices as recorded by the PHLX are not as accurate as the Reuters exchange rates provided by Olsen and Associates, probably because of time lags in the Telerate data.
Myocardial ischemia and infarction

Atherosclerotic heart disease is the leading cause of death in developed nations. Manifestations include myocardial ischemia or infarction. In addition, some patients develop cardiovascular insufficiency, with the additional risk of systemic ischemia. Hypothermia has been shown to protect tissues during ischemia and thus may have clinical benefit in patients with cardiovascular disorders. This chapter will explore the potential therapeutic role for hypothermia in regional and global myocardial ischemia, as well as systemic ischemia secondary to heart failure.
MAGNETIC TRANSLATION GROUP. II. IRREDUCIBLE REPRESENTATIONS

The physical irreducible representations of the magnetic translation group (M.T.G.) defined previously have been found. From these a set of solutions of Schr\"odinger's equation for a Bloch electron in a magnetic field has been constructed. In general the M.T.G. is non-Abelian. However, when the magnetic flux through areas enclosed by any vectors of the Bravais lattice become multiples of an elementary "fluxon" $\frac{\mathrm{hc}}{e}$, the M.T.G. becomes isomorphic to the usual translation group.
PAYING ATTENTION TO WHITENESS AND CLASS

Juliet Hooker's Race and the Politics of Solidarity and Stanley R. Bailey's Legacies of Race both tackle the crucial question of what kinds of policies states with diverse populations and histories of social inequality should enact in the effort to move towards racial justice. Hooker bases her claims on a case study of multicultural reforms in Nicaragua. Bailey uses survey data to analyze racial attitudes and race-based policies in Brazil. Both Hooker and Bailey critique prior efforts to make generalizations about racial boundaries and multicultural politics on the basis of the U.S. case, and both contend that their arguments will apply beyond the particular case they analyze.
Backscattering Scanning Fluorescence Microscopy

We present a microscopy technique in which a scattering optical element is used for scanning and resolution enhancement. The measured backscattering matrix is used to scan light with a twofold improvement in system resolution.
Errata in implicit multifunction theorems for the sensitivity analysis of variational conditions

This note corrects a faulty application of the theory in [3] to the sensitivity analysis of stationary points associated with nonlinear programs. Corrected sufficient conditions are given for the local upper Lipschitz continuity of these stationary points.
Natural history of IgE-dependent food allergy diagnosed in children during the first three years of life

ABSTRACT Purpose The aim of the study was to analyze: the course of allergy diagnosed during first three years of life, frequency of food tolerance development and impact of factors which have potential meaning in that process. Material and Methods The study was performed in 115 children with IgE-dependent allergy, diagnosed during first three years of life, treated in 2nd Department of Pediatrics and Allergology of Polish Mothers Health Center in Lodz. All children were invited to our clinic in order to analyze course of the allergy after period of minimum 5 years since diagnosis. Results The results of the study revealed that food tolerance was acquired by high percentage of examined children (87.9%) among 83 children with food allergy. However among 32 children with initial inhalant allergy there were still no food sensitizations. The frequency of this process increased with age of examined children. The study revealed that such factors as lack of family history of atopy, clinical manifestation limited to one system, lack of inhalant allergy, type of allergen, good social conditions, have positive impact on tolerance development. Conclusions High percentage of children with food allergy is able to develop the status of food immunotolerance. Factors which predispose to development of food allergy have also negative impact on ability to acquiring tolerance to harmful food. The study indicates the need of constant and wide education about decreasing exposure to allergy predisposing factors which could increase chance of food tolerance development.
The influence of nucleation criterion on shear localization in rate-sensitive porous plastic solids

Abstract The influence of the void nucleation criterion on localization in strain rate-sensitive porous plastic solids is analyzed under plane strain and axisymmetric tensile loading conditions using an infinite band model. The void nucleation process is described in terms of a void nucleation stress that depends linearly on the hydrostatic tension with a coefficient that is less than unity. Although the nucleation strain depends monotonically on the void nucleation stress coefficient, the dependence of the localization strain on this quantity is not necessarily monotonic. With the void nucleation stress coefficient fixed, there can also be a nonmonotonic dependence of the critical strain for localization on imposed strain rate.
Using queue structures to improve job reliability

Many high performance computing systems today exploit the availability and remarkable performance characteristics of stand alone server systems and the impressive price / performance ratio of commodity components. Small scale HPC systems, in the range from 16 to 64 processors, have enjoyed significant popularity and are an indispensable tool for the research community. Scaling up to hundreds and thousands of processors, however, has exposed operational issues, which include system availability and reliability. In this paper, we explore the impact of individual component reliability rates on the overall reliability of an HPC system. We derive a mathematical model for determining the failure rate of the system, the probability of failure of a job running on a subset of the system, and show how to design a reasonable queue structure to provide a reliable system over abroad job mix. We also explore the impact of reliability and queue structure on checkpoint intervals and recovery. Our results demonstrate that it is possible to design a reliable high performance computing system with very good operational reliability characteristics from a collection of moderately reliable components.
Androgen production by monkey luteal cell subpopulations at different stages of the menstrual cycle

Androgens produced by the primate corpus luteum (CL) serve as precursors for estrogen synthesis; moreover, detection of androgen receptors in luteal tissue suggests a regulatory role within the CL. To determine the cellular source(s) and agonist regulation of androgen production during the lifespan of the primate CL, luteal tissues were collected from rhesus monkeys in the early (days 3-5 post-LH surge), mid (days 7-8), mid-late (days 11-12), and late (days 14-15) luteal phase of the menstrual cycle. Collagenase-dispersed cells (i.e., mixed cells) were analyzed by flow cytometry based on light scatter properties and sorted into populations of small ( 20 microns) luteal cells. Cells (n = 4 animals/stage) were incubated in Ham's F-10 and 0.1% BSA for 3 h at 37 C with or without hCG (100 ng/mL), PGE2 (14 mumol/L), or dibutyryl cAMP (dbcAMP; 5 mmol/L), and androstenedione (A4) and testosterone were measured. Basal A4 production by large cells was markedly higher (P < 0.05) than that by small cells (e.g. mid-late luteal phase, 821 +/- 188 vs. 69 +/- 25 pg/mL.5 x 10(4) cells/3 h; mean +/- SEM), whereas that by mixed cells was intermediate (317 +/- 205 pg/mL). In the early luteal phase, hCG stimulated A4 synthesis by mixed (1.6-fold; P < 0.05) and large (3.1-fold; P < 0.05) luteal cells, but not by small cells (1.3-fold). By the mid-late luteal phase, hCG did not increase A4 production by any cell type, although hCG responsiveness returned to large cells (2.0-fold increase; P < 0.05) by the late luteal phase. PGE2 responsiveness by cell types was similar to that of hCG, except large cell responsiveness did not return in the late luteal phase. In all cell types, dbcAMP stimulated the largest increase in A4 levels; in the mid-late luteal phase, small and large cells responded to dbcAMP with 8.2- and 3.0-fold increases (P < 0.05) in A4 production, respectively. When luteal cells were incubated with the steroidogenic substrates, 17 alpha-hydroxyprogesterone or 17 alpha-hydroxypregnenolone (1 mumol/L), large cells produced much more (P < 0.05) A4, testosterone, estrone, and estradiol than small cells. Both substrates elicited similar patterns of androgen production, with A4 synthesis predominant in all luteal cell types. Thus, cell subpopulations in the primate CL can be distinguished by their ability to produce androgen and estrogen. Changes in agonist-responsive androgen production may influence the local steroid milieu and function of the CL during the menstrual cycle.
Second-order conditioning of the pigeon’s keypeck

Pigeons learned to peck a keylight (S2) when it was paired with a stimulus (S1) that already evoked keypecking. Control procedures showed that S2 acquired control over responding because it was paired with S1 and because S1 had a conditioning history, thereby supporting the claim that S2 was a second-order conditioned stimulus. Second-order conditioning occurred as rapidly when S1 was a keylight as when it was a tone. Test procedures showed that after second-order conditioning, responding to S2 was markedly debilitated by the extinction of responding to S1, indicating that the ability of S2 to evoke a response importantly depends upon the continued ability of S1 to do so. Our demonstration that directed motor action in the pigeon is susceptible to second-order conditioning suggests a new interpretation of conditioned reinforcement in instrumental learning. Our demonstration that the effectiveness of S2 depends upon the continued effectiveness of S1 indicates that S-S associations are formed in this version of the second-order conditioning experiment.
Explosives: a microsensor for trinitrotoluene vapour.

Sensing devices designed to detect explosive vapours are bulky, expensive and in need of technological improvement — dogs remain the most effective detectors1 in the fight against terrorism and in the removal of land-mines2,3. Here we demonstrate the deflagration of trinitrotoluene (TNT) in a small localized explosion on an uncoated piezoresistive microcantilever. This explosive-vapour sensor, which has a detection capability that is comparable to that of a dog, should enable extremely sensitive, miniature detection devices to be used on a large scale.
Anisotropic edge retraction and hole growth during solid-state dewetting of single crystal nickel thin films

At elevated temperatures, single crystal thin films sometimes undergo solid-state dewetting to form holes and islands with anisotropic morphologies and regular features. We have measured the rates of edge retraction for single crystal Ni(1 0 0) and Ni(1 1 0) films with edges patterned along different in-plane crystallographic directions. The polar plots of the edge retraction velocities have anisotropic shapes with prominent cusps in particular directions. The characteristic anisotropy in the edge retraction velocity can be understood in terms of in-plane orientation-dependent edge faceting, with single faceting of specific edges and multiple micro-faceting in other edges. Faceting occurs due to surface energy minimization, and is modified by changes in the annealing ambient. Changes in facet morphologies affect the relative edge retraction rates in different crystallographic orientations and also the initial shapes of holes growing in the film. The mechanistic understanding of edge retraction provided through these studies will provide a basis for understanding the evolution of complex morphologies that result from solid-state dewetting of unpatterned single crystal films.
Consumer Product Export Opportunities to Liberalizing LDCS A Life-Cycle Approach

This paper reviews popular and academic literature in order to describe several relationships which appear to exist between liberalization in LDCs and imports of consumer goods. Based on this review, the parameters of a life-cycle model are developed for consumer product exports to liberalizing LDCs. Such exports are hypothesized to: (1) be minimal prior to liberalization, and (2) rise rapidly in the early stages of liberalization, and (3) decline, sometimes precipitously, several years later. These hypotheses are tested using consumer import data from three unique LDCs: Chile, Egypt and China. Finally, the implications of the model for LDC governments, exporters and foreign investors are explored.
Strain differences in myenteric neuron number and CCK1 receptor mRNA expression may account for differences in CCK induced c-Fos activation.

Abstract We utilized a diaminobenzidine reaction enhanced with nickel to compare dorsal vagal complex (DVC) and myenteric neuronal Fos-Like immunoreactivity (Fos-LI), in response to sulfated cholecystokinin-8 (CCK-8) (5, 10, 20, 40 μg/kg), among Sprague–Dawley (SD), Standard Long–Evans (SLE), Otsuka Long-Evans Tokushima Fatty (OLETF), and Long–Evans Tokushima Otsuka (LETO) rats. All rat strains but OLETF expressed Fos-LI in response to CCK-8. In addition, SD rats expressed more Fos-LI in the area postrema and myenteric neurons than SLE and LETO rats. To investigate the basis for these differences, we utilized cuprolinic blue staining, which stains neuronal cell bodies, to quantify the number of myenteric neurons, and a reverse transcriptase chain polymerase reaction to measure the gene expression of CCK1 receptor in the gut. We found that SD rats have significantly more duodenal myenteric neurons than the other strains. In addition, this strain expressed significantly higher levels of the CCK1 gene in both the duodenum and jejunum than the other strains. In conclusion, SD rats may express more myenteric Fos-LI in response to CCK due to increased numbers of myenteric neurons or more intestinal CCK1 receptors than the other strains of rats.
Nonerosive reflux disease: a pathophysiologic perspective.

Nonerosive reflux disease (NERD) is the most common phenotype of gastroesophageal reflux disease. By definition, patients with NERD have typical reflux symptoms caused by the intraesophageal reflux of gastric contents but have no visible esophageal mucosal injury. This is in contrast to patients with reflux esophagitis, also known as erosive reflux disease, and Barrett’s esophagus, who have obvious esophageal mucosal injury on endoscopy. Only 50% of patients with NERD have pathologic esophageal acid contact time (ACT) as detected on 24-hour pH monitoring (ie, NERD-positive). NERD patients with physiologic esophageal ACT and good temporal correlation of symptoms with reflux events (symptom index > 50% or symptom-association probability > 95%) are considered to have esophageal hypersensitivity (ie, NERD-negative). Finally, patients with physiologic esophageal ACT but poor symptom-reflux correlation are now considered to have functional heartburn and not NERD. NERD-positive patients have motor dysfunction and acidic reflux abnormalities that are similar to patients with reflux esophagitis and Barrett’s esophagus, whereas NERD-negative patients have minimal abnormalities that are not much different than healthy controls. The histopathologic feature most indicative of NERD is the presence of dilated intercellular spaces within squamous epithelium, an ultrastructural abnormality readily identified on transmission electron microscopy and on light microscopy.
Scaling laws for data-centric storage and querying in wireless sensor networks

We use a constrained optimization framework to derive scaling laws for data-centric storage and querying in wireless sensor networks. We consider both unstructured sensor networks, which use blind sequential search for querying, and structured sensor networks, which use efficient hash-based querying. We find that the scalability of a sensor network's performance depends upon whether the increase in energy and storage resources with more nodes is outweighed by the concomitant application-specific increase in event and query loads. We derive conditions that determine: 1) whether the energy requirement per node grows without bound with the network size for a fixed-duration deployment, 2) whether there exists a maximum network size that can be operated for a specified duration on a fixed energy budget, and 3) whether the network lifetime increases or decreases with the size of the network for a fixed energy budget. An interesting finding of this work is that three-dimensional (3D) uniform deployments are inherently more scalable than two-dimensional (2D) uniform deployments, which in turn are more scalable than one-dimensional (1D) uniform deployments.
Increasing Accountability: Faculty Perspectives on the English Language Competence of Nonnative English Speakers.

The cultural, ethnic, and linguistic diversity of today’s tertiary students necessitates exploring a variety of approaches to support learning. This study reports on a university’s efforts to under...
Monoclonal antibodies to conformational epitopes of the surface glycoprotein of caprine arthritis-encephalitis virus: potential application to competitive-inhibition enzyme-linked immunosorbent assay for detecting antibodies in goat sera.

Four immunoglobulin G1 monoclonal antibodies (MAbs) to the gp135 surface envelope glycoprotein (SU) of the 79–63 isolate of caprine arthritis-encephalitis virus (CAEV), referred to as CAEV-63, were characterized and evaluated for their ability to compete with antibody from CAEV-infected goats. Three murine MAbs (MAbs GPB16A, 29A, and 74A) and one caprine MAb (MAb F7-299) were examined. All MAbs reacted in nitrocellulose dot blots with native CAEV-63 SU purified by MAb F7-299 affinity chromatography, whereas none reacted with denatured and reduced SU. All MAbs reacted in Western blots with purified CAEV-63 SU or the SU component of whole-virus lysate following denaturation in the absence of reducing agent, indicating that intramolecular disulfide bonding was essential for epitope integrity. Peptide-N-glycosidase F digestion of SU abolished the reactivities of MAbs 74A and F7-299, whereas treatment of SU with N-acetylneuraminate glycohydrolase (sialidase A) under nonreducing conditions enhanced the reactivities of all MAbs as well as polyclonal goat sera. MAbs 29A and F7-299 were cross-reactive with the SU of an independent strain of CAEV (CAEV-Co). By enzyme-linked immunosorbent assay (ELISA), the reactivities of horseradish peroxidase (HRP)-conjugated MAbs 16A and 29A with homologous CAEV-63 SU were <10% of that of HRP-conjugated MAb 74A. The reactivity of HRP-conjugated MAb 74A was blocked by sera from goats immunized with CAEV-63 SU or infected with CAEV-63. The reactivity of MAb 74A was also blocked by sera from goats infected with a CAEV-Co molecular clone, although MAb 74A did not react with CAEV-Co SU in Western blots. Thus, goats infected with either CAEV-63 or CAEV-Co make antibodies that inhibit binding of MAb 74A to CAEV-63 SU. A competitive-inhibition ELISA based on displacement of MAb 74A reactivity has potential applicability for the serologic diagnosis of CAEV infection.
Effects of emission characteristics on air quality during simulated air pollution episodes

Abstract A major application of air pollution dispersion models is to aid in the selection of abatement plans. Present technology dictates that air pollution abatement be a result of altering an area's emission characteristics. The need for pollution abatement is most acute during air pollution episodes. This study is an investigation of how air quality in a hypothetical city is affected by the city's emission characteristics during a simulated air pollution episode. Emission characteristics examined include configuration of sources, diurnal emission rate schedules, total emission rates, and the combination of point and area sources. Results are used to gain insight into how models may be used to reduce air pollution emergencies through long term planning and short term abatement schemes. Among the observations are: 1. (1) air quality is improved significantly by selecting configurations whose major sources are too far apart to jointly contaminate a locality. Increasing the mean distance between major sources 75 per cent led to an improvement in air quality as high as 28 per cent; 2. (2) altering diurnal schedules of emission rates to take advantage of diurnal variations in atmospheric dilutive capacity improved air quality by as much as 23 per cent; 3. (3) the set of priorities given to emission rate reductions of different types of sources is an important determinant of air quality improvement attained with a given reduction in the total emission rate. Differences as high as 28 per cent were observed for a given reduction in the total emission rate; 4. (4) pollutant concentration at a receptor location is primarily the result of emissions in contiguous locations; 5. (5) longer time lags between emission rate reductions and air quality improvement during episodes place a premium on controls which can be implemented quickly. The model is verified using St. Louis emission data. Predicted concentrations are within a factor of 1.4 of observed ones.
A procedure for developing a quality-of-life measure for epilepsy surgery patients.

In 1990, the NIH Consensus Conference Panel on epilepsy surgery called for the development and use of reliable and valid health-related quality-of-life (HRQOL) measures in epilepsy surgery studies. A HRQOL measure for epilepsy surgery patients has been developed and evaluated. The procedure, which could also be used to develop HRQOL measures for other neurological diseases, entails the following steps: (a) specify desired characteristics of the measure; (b) identify relevant HRQOL areas by reviewing the literature; (c) assemble generic core items and disease-specific supplementary items; (d) pilot test and revise the measure: (e) administer revised measure items to a large sample of epilepsy surgery patients; (f) perform item analysis to evaluate hypothesized item placement within scales; and (g) asses teh reliability and validity of the scales
In the Pursuit of Happiness?: Consumers of Erotica in San Francisco

This study of consumers of erotica is based upon observational data from adult movie theaters, bookstores, and arcades, and upon indepth questionnaires from two samples of movie theater patrons. Data from over 4000 observations and 251 questionnaires were compared. The average consumer of erotica in San Francisco appears as a white, middle-aged, married male, neatly attired and shopping alone. Questionnaire data reveal that these patrons are also well-educated, highly paid, and employed in white-collar or above occupations. Most consumers lead an active and varied sex life and report that involvement in the erotic marketplace increases their social and sexual interaction.
The genetic structure of recombinant inbred mice: High-resolution consensus maps for complex trait analysis

Background: Recombinant inbred (RI) strains of mice are an important resource used to map and analyze complex traits. They have proved particularly effective in multidisciplinary genetic studies. Widespread use of RI strains has been hampered by their modest numbers and by the difficulty of combining results derived from different RI sets. Results: We have increased the density of typed microsatellite markers two- to five-fold in each of several major RI sets that share C57BL/6 as a parental strain (AXB, BXA, BXD, BXH and CXB). A common set of 490 markers was genotyped in just over 100 RI strains. Genotypes of around 1,100 additional microsatellites in one or more RI sets were generated, collected and checked for errors. Consensus RI maps that integrate genotypes of approximately 1,600 microsatellite loci were assembled. The genomes of individual strains typically incorporate 45-55 recombination breakpoints. The collected RI set - termed the BXN set - contains approximately 5,000 breakpoints. The distribution of recombinations approximates a Poisson distribution and distances between breakpoints average about 0.5 centimorgans (cM). Locations of most breakpoints have been defined with a precision of < 2 cM. Genotypes deviate from Hardy-Weinberg equilibrium in only a small number of intervals. Conclusions: Consensus maps derived from RI strains conform almost exactly to theoretical expectation and are close to the length predicted by the Haldane-Waddington equation (x3.6 for a 2-3 cM interval between markers). Non-syntenic associations between different chromosomes introduce predictable distortions in quantitative trait locus (QTL) datasets that can be partly corrected using two-locus correlation matrices.
Isolating human transcription factor targets by coupling chromatin immunoprecipitation and CpG island microarray analysis

Previously, identification of promoters regulated by mammalian transcription factors has relied upon overexpression studies. Here we present the identification of a large set of promoters that are bound by E2F in physiological conditions. Probing a human CpG microarray with chromatin immunoprecipitated using an antibody to E2F4, we have identified 68 unique target loci; 15% are bidirectional promoters and 25% recruit E2F via a mechanism distinct from the defined consensus site. Interestingly, although E2F has been shown previously to regulate genes involved in cell cycle progression, many of the new E2F target genes encode proteins involved in DNA repair or recombination. We suggest that human CpG microarrays, in combination with chromatin immunoprecipitation, will allow rapid identification of target promoters for many mammalian transcription factors.