cssi/SciSciGPT-SciSciNet huggingface dataset:
Glucose metabolism in man: Responses to intravenous glucose infusion

We have determined the effect of unlabeled glucose infusions, with and without added insulin, on glucose metabolism in normal male volunteers by means of the simultaneous primed-constant infusion of 6-3H and U-13C-glucose. Glucose kinetics were measured after 90 min of infusion. When steady state had been reached, endogenous glucose production (2.53 +/- .058 mg/kg . min, X +/- SEM) was suppressed at all rates of exogenous glucose tested (1, 2, and 4 mg/kg . min). The absolute degree of suppression was most marked (75%) at the highest rate of infusion, but the greatest degree of suppression, relative to infusion rate, was at the lowest infusion rate. The control of plasma glucose concentration during the glucose infusion was achieved primarily through regulation of endogenous Ra. The rate of uptake of glucose only increased during the 4 mg/kg . min infusion, even though there were significant elevations in the plasma glucose and insulin concentrations during the 2 mg/kg . min infusion as well. The glucose clearance rate increased only when sufficient insulin was infused with the 4 mg/kg . min glucose infusion to control the hyperglycemia that developed if no insulin was administered. Approximately 43% of the infused glucose was directly oxidized when the infusion rate was 1 or 2 mg/kg . min. That value fell to 32% when the infusion rate was increased to 4 mg/kg . min, regardless of whether insulin was infused or not.
The Future of Conventional Arms Control

Dramatic changes in conventional military capabilities coupled with nuclear parity should greatly increase the importance of conventional military power as well as raise new opportunities and problems for arms control. Those changes are not yet widely appreciated and in fact, there is a lack of analytic tools by which to appraise their implications and importance.
High Drift Rate Effects of Propanil and Basis Gold on the Plankton Communities and Water Quality of a Prestocking Sunshine Bass, Morone chrysops × M. saxatilis, Fry Pond

ABSTRACT Mesocosm-testing of aerially applied herbicides propanil and Basis Gold (86.8% atrazine) and indicated high drift rates (10–20% of field rates) resulted in adverse impacts on aquaculture production-pond phytoplankton, zooplankton, and critical water-quality variables. Effects on fry pond phytoplankton, zooplankton, and water quality from these herbicides were evaluated at 30% of field application rates, equal to the worst-case scenario from drift to these smaller ponds with consequent higher concentrations. The study was conducted in 12 outdoor pool mesocosms of 500 L volume, filled with pond water from an adjacent 0.1 ha pond fertilized and prepared as recommended for sunshine bass, Morone chrysops × M. saxatilis, fry stocking. Plankton and water quality samples were taken just prior to herbicide application (day 0) and on days 1,2,3,4-zooplankton only, and on day 7 after application. Field application rates for Basis Gold and propanil were 0.8 kg active ingredient and 1.80 kg/ha, respectively. ...
Acute hemodynamic effects of intravenous isradipine

The acute hemodynamic effects of isradipine, a new dihydropyridine calcium antagonist, were evaluated in 16 men referred for elective cardiac catheterization. Low-dose (0.007 mg/kg, n = 8) and high-dose (0.015 mg/kg, n = 8) isradipine was administered intravenously over 10 minutes and the hemodynamic alterations assessed 10 minutes after completion of infusion. Low-dose isradipine caused increases in heart rate (68 +/- 9 to 79 +/- 12 beats/min, p less than 0.001) (mean +/- standard deviation), cardiac index (3.0 +/- 0.7 to 4.1 +/- 0.9 liter/min/m2, p less than 0.001) and coronary sinus blood flow (114 +/- 27 to 162 +/- 74 ml/min, p less than 0.01), and significant decreases in mean aortic pressure (104 +/- 17 to 92 +/- 10 mm Hg, p less than 0.01), systemic and coronary vascular resistance. High-dose isradipine caused similar effects: the heart rate increased (72 +/- 6 to 84 +/- 14 beats/min, p less than 0.005), as did the cardiac index (3.0 +/- 0.6 to 4.6 +/- 0.9 liter/min/m2, p less than 0.001) and coronary sinus blood flow (122 +/- 48 to 166 +/- 47 ml/min, p less than 0.025). In addition, there were increases in the stroke volume index (43 +/- 10 to 55 +/- 8 ml/m2, p less than 0.001) and left ventricular stroke work index (69 +/- 12 to 79 +/- 12 g-m/m2, p = 0.05) after the high-dose infusion. Vascular resistance declined significantly in the systemic, pulmonary and coronary beds.(ABSTRACT TRUNCATED AT 250 WORDS)
Protamine-Sensitive Polymer Membrane Electrode: Characterization and Bioanalytical Applications

A polymeric membrane electrode that exhibits significant and analytically useful potentiometric response to submicromolar levels of the heparin antagonist, protamine, is reported. The sensor is prepared by incorporating a lipophilic cation exchanger, potassium tetrakis(4-chlorophenyl)borate (KTpClPB) (at 1 wt%), within a specially formulated polymer membrane composed of 33 wt% 2-nitrophenyl octyl ether (2-NPOE), and 66 wt% poly(vinyl chloride) (PVC). When the polymer film is mounted in an appropriate electrode body, the resulting membrane electrode responds reproducibly to protamine via a nonequilibrium quasi-steady-state change in the phase boundary potential at the membrane/sample interface. Such response can be used to directly monitor, via classical potentiometric titrations, the binding between protamine and a variety of native (porcine and beef) as well as low-molecular-weight heparins. Scatchard analysis of the EMF titration data provides binding constants and stoichiometries for protamine-heparin interactions. The electrode can be further used to follow the enzymatic digestion of protamine by trypsin. In the presence of a given level of protamine, initial rates of potential decrease (-dE/dt) are shown to be linearly related to trypsin activity in solution over the range of 0-130 units/ml. The speed and simplicity of the protamine sensor make it an attractive alternative to classical methods for studying the interaction of protamine with other biologically important macromolecules as well as the proteolytic activity and reaction kinetics of trypsin.
Dialog Behavior: How Sampling Intervals Affect Estimates of Sound and Silence:

In using computerized systems for analyzing temporal patterns of sounds and silence arising from two-speaker dialog, sampling rates alter estimates of durations of these vocal parameters. Results are reported using the same vocal samples, altering only the sampling intervals, from 2 to 100 samples per second. Significant differences were found in mean durations of pauses and vocalizations among the sampling intervals. An optimal sampling interval of 10 samples per second is suggested.
Olivopontocerebellar atrophy in carbohydrate-deficient glycoprotein syndrome.

(1995). Case 4 Olivopontocerebellar Atrophy in Carbohydrate-Deficient Glycoprotein Syndrome. Pediatric Pathology & Laboratory Medicine: Vol. 15, No. 1, pp. 175-179.
Immunoaffinity purification and fluorescence studies of human adenosine deaminase

Human thymus adenosine deaminase was isolated by using a monoclonal antibody affinity column. The highly purified enzyme produced by this rapid, efficient procedure had a molecular weight of 44,000. Quenching of the intrinsic protein fluorescence by small molecules was used to probe the accessibility of tryptophan residues in the enzyme and enzyme-inhibitor complexes. The fluorescence emission spectrum of human adenosine deaminase at 295-nm excitation had a maximum at about 335 nm and a quantum yield of 0.03. Addition of polar fluorescence quenchers, iodide and acrylamide, shifted the peak to the blue, and the hydrophobic quencher trichloroethanol shifted the peak to the red, indicating that the emission spectrum is heterogeneous. The fluorescence quenching parameters obtained for these quenchers reveal that the tryptophan environments in the protein are relatively hydrophobic. Binding of both ground-state and transition-state analogue inhibitors caused decreases in the fluorescence intensity of the enzyme, suggesting that one or more tryptophans may be near the active site. The kinetics of the fluorescence decrease were consistent with a slow conformational alteration in the transition-state inhibitor complexes. Fluorescence quenching experiments using polar and nonpolar quenchers were also carried out for the enzyme-inhibitor complexes. The quenching parameters for all enzyme-inhibitor complexes differed from those for the uncomplexed enzyme, suggesting that inhibitor binding causes changes in the conformation of adenosine deaminase. For comparison, parallel quenching studies were performed for calf adenosine deaminase in the absence and presence of inhibitors. While significant structural differences between adenosine deaminase from the two sources were evident, our data indicate that both enzymes undergo conformational changes on binding ground-state and transition-state inhibitors.
Generalized Lifshitz-Kosevich scaling at quantum criticality from the holographic correspondence

We characterize quantum oscillations in the magnetic susceptibility of a quantum critical non-Fermi liquid. The computation is performed in a strongly interacting regime using the nonperturbative holographic correspondence. The temperature dependence of the amplitude of the oscillations is shown to depend on a critical exponent $\ensuremath{\nu}$. For general $\ensuremath{\nu}$ the temperature scaling is distinct from the textbook Lifshitz-Kosevich formula. At the ``marginal'' value $\ensuremath{\nu}=\frac{1}{2}$, the Lifshitz-Kosevich formula is recovered despite strong interactions. As a by-product of our analysis we present a formalism for computing the amplitude of quantum oscillations for general fermionic theories very efficiently.
Histone Acetylation Regulates the Time of Replication Origin Firing

The temporal firing of replication origins throughout S phase in yeast depends on unknown determinants within the adjacent chromosomal environment. We demonstrate here that the state of histone acetylation of surrounding chromatin is an important regulator of temporal firing. Deletion of RPD3 histone deacetylase causes earlier origin firing and concurrent binding of the replication factor Cdc45p to origins. In addition, increased acetylation of histones in the vicinity of the late origin ARS1412 by recruitment of the histone acetyltransferase Gcn5p causes ARS1412 alone to fire earlier. These data indicate that histone acetylation is a direct determinant of the timing of origin firing.
Differences between perinatal angiotensin binding in the brains of SHR and WKY rats

A growing body of evidence suggests that angiotensin may have a functional role in growth and development, in addition to its classical role in the maintenance of body water homeostasis. Components of the renin-angiotensin system have been identified in the rat fetus. Because of the association between the renin-angiotensin system and hypertension, we quantified angiotensin receptor binding sites in the brains of spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) rats during perinatal development. Using in vitro receptor autoradiography we identified specific 125I-Sar1,Ile8 AII binding in several areas of the brains of perinatal rats of both strains and observed significant differences in the concentration of binding sites, at different ages in several brain nuclei. With the knowledge that components of the renin-angiotensin system appear early in development and are known to have an association with cellular growth, it is possible that an irregularity in this system occurring during neurogenesis could contribute to developmental abnormalities, as well as subsequent hypertension.
Linking the public voice with the genetic policy process: a case study

The application of genetic information will shape economies and lives throughout the next century and beyond. At the current pace of discovery, genetic research will bring advances in pharmaceuticals and therapeutic treatments that not only serve to reduce human suffering, but also offer people new choices and greater control over their lives. But, what humanity will do with this new technology and knowledge remains to be seen. Current thinking on our genetic future ranges from fearful predictions of dire consequences to bold visions of disease-free existence. Should citizens play a role in deciding how this new genetic information and technology will be used? And what strategies should be developed to achieve that goal? Geneforum, a new non-profit organization that works to incorporate public ethics and values into the genetic science policy making process through grassroots education and Internet dialogue, believes that citizens should be informed and active participants in the Gene Age. Geneforum creates environments for learning, facilitates forums for discussion and provides input to policy makers. Classroom workshops, Town Hall Meetings, public opinion research, publications, an interactive Web site, and talk-radio programming are all used to achieve these ends. Geneforum's experience in employing these communication strategies to help guide genetic privacy policy development in Oregon is the focus of this paper.
Emergency Medicine in Madagascar

The Democratic Republic of Madagascar lies off the southeastern coast of Africa and ranks as the fourth largest island in the world. Average per capita yearly income is about $400 (US). In 1990 life expectancies at birth were 52 years for men and 55 years for women. Graduate medical education in Madagascar is modeled after the French system.
Reconstruction of Superior Vena Cava Syndrome due to Benign Disease Using Superficial Femoral Vein

Superior vena cava (SVC) syndrome due to benign disease requires prompt and durable treatment because affected patients frequently have long life expectancies. While conservative management with head elevation and anticoagulation are first-line treatments, refractory symptoms may warrant intervention. The two main invasive treatments are percutaneous endovascular repair and open surgical reconstruction. Both have demonstrated efficacy over the mid term, but surgical reconstruction is the only method with proved patency over the long term. This report documents a case of a 26-year-old woman with SVC syndrome secondary to long-term indwelling central venous catheterization. SVC bypass was performed using the superficial femoral vein, and near-complete resolution of symptoms occurred within 1 week. Superficial femoral vein is a versatile conduit for SVC reconstruction and a useful alternative to spiral saphenous vein grafts, although mid- and long-term patency rates must be further studied.
Synthesis of high phase pure cuprate superconductors via xerogel precursors

Phase pure YBa2Cu3O7 high transition temperature superconductor powders were synthesized by a new precursor route. This new synthesis procedure is easy, leads to an atomic mixture of the relevant constituents, and is readily adaptable to many other systems or to the doping of existing systems. A gel of yttrium, barium, and copper salts was prepared using organic gelling agents. The gel was then dried and ground, leaving the xerogel precursor. These xerogels are perfectly stable even under high humidity atmospheric conditions and show an amorphous structure when characterized by x-ray diffraction, which is consistent with the existence of an atomic mixture of the three relevant metal salts. The organic gelling agent was selected after optimization studies focused on such issues as ash residue after calcination, solubility, and chemical interference with the metal salts. From a great variety of these gelling agents (agar, xanthan gum, gelatin, alginates, and others), gelatin was chosen as the ideal gelling agent for this specific application. The final product characterization shows very unexpected results. The crystalline phase purity of the YBa2Cu3O7 superconducting phase was about 99%, with no traces of barium carbonate, as expected from pseudo-organic precursors (xerogels). The product shows superconducting properties even before oxygen anneal (Tc ≍ 70 K), and after oxygen annealing of the powders the transition temperature was found to be 91 K, showing a linear behavior of the resistivity versus temperature before the drop at Tc, extrapolating to zero at 0 K. The particle size of these powders is smaller than 1 μm, as shown by SEM.
DYNAMICS OF THE FEEDING MECHANISM OF LARGE GALEOID SHARKS

A few species of sharks have jaws structurally effective for crushing hard-shelled prey, but the functions of the jaws and teeth of the remaining species, that is of most kinds of sharks, are restricted to grasping prey or to cutting off pieces of prey to get something of suitable size for swallowing. The grasping function is one which may be performed by any shark; but the type of jaw and dentition apparently most effective and most restricted for this pur? pose is that found in the sand shark, Carcharias taurus, one of the more primitve of existing galeoids. The sand shark has teeth especially adapted for holding. The teeth are long, spike-like, and irregularly spaced and are held permanently in position to function in more than one series. The sand shark has
Increased expression of growth-associated protein (GAP-43) in lower urinary tract pathways following cyclophosphamide (CYP)-induced cystitis

Abstract Alterations in the expression of growth-associated protein 43 (GAP-43) were examined in lower urinary tract micturition reflex pathways in a chronic model of cyclophosphamide (CYP)-induced cystitis. In control animals, expression of GAP-43 was present in specific regions of the gray matter in the rostral lumbar and caudal lumbosacral spinal cord, including: (1) the dorsal commissure; (2) the dorsal horn and (3) the regions of the intermediolateral cell column (L 1 –L 2 ) and the sacral parasympathetic nucleus (L 6 –S 1 ) and (4) in the lateral collateral pathway of Lissauer in L 6 –S 1 spinal segments. Densitometry analysis has demonstrated significant increases ( p ≤0.001; 1.5–4.0-fold increase) in GAP-43-immunoreactivity (IR) in these regions of the rostral lumbar (L 1 –L 2 ) and caudal lumbosacral (L 6 –S 1 ) spinal cord following CYP-induced urinary bladder inflammation. Changes in GAP-43-IR were restricted to those segmental levels examined (L 1 –L 2 and L 6 –S 1 ) that are involved in lower urinary tract reflexes. Changes in GAP-43-IR were not observed at the L 5 segmental level. In contrast to significant increases in GAP-43-IR in specific regions of the rostral lumbar and caudal lumbosacral spinal cord, no changes in GAP-43-IR were observed in the L 1 , L 2 or L 6 , S 1 dorsal root ganglia (DRG). In control animals, virtually all retrogradely labeled (Fast Blue) bladder afferent cells in the L 1 , L 2 and L 6 , S 1 DRG expressed GAP-43-IR. This percentage (∼100%) of bladder afferent cells expressing GAP-43-IR was unchanged following CYP-induced urinary bladder inflammation. Alterations in GAP-43-IR following chronic cystitis may suggest a reorganization of bladder afferent projections and spinal elements involved in bladder reflexes consistent with alterations in bladder function observed in animal models of cystitis.
Female sexual dysfunction, voiding symptoms and depression: common findings in partners of men with erectile dysfunction.

The aim of this study was to investigate the prevalence of female sexual dysfunction (FSD), urinary symptoms, and depressive symptoms in female partners of men presenting with erectile dysfunction (ED). A multi-component questionnaire was administered to female partners of men with erectile dysfunction presenting to a urology center. It contained a standardized sexual function component (the Brief Index of Sexual Function for Women), a depression scale (Centers for Epidemiologic Studies-Depression, CES-D), a demographics questionnaire and a general medical questionnaire. A total of 73 consecutive female partners of male patients presenting with ED, were surveyed using the questionnaire at their counterpart’s visit. Fifty-two women responded, of whom 50 filled out the questionnaire adequately for proper evaluation. This indicated a response rate of 68% (50/73). The mean age was 44.8 years (range 20.0–83.0). Thirty-eight of the 50 women (76%) reported being sexually active. A variety of sexual behaviors were reported including 40% (20/50) of women engaging in vaginal intercourse. Sexual dysfunction symptoms included: anxiety/inhibition (26%), hypoactive desire (20%), arousal/lubrication difficulty (30%), orgasmic difficulty (24%), dyspareunia (18%), incontinence during intercourse (8%), and sexual dissatisfaction (34%). Eight women (16%) reported difficulty communicating sexual issues with their partners. Forty-one women (82%) rated sexual activity as an important part of their lives. Urinary symptoms of frequency and urgency were reported by 18/50 (36%). Depressive symptoms were present in 22/50 (44%). FSD disorders, urinary symptoms and depressive symptoms are common in partners of men with erectile dysfunction.
A dialogue on Zeno's paradox of Achilles and the tortoise

The five participants in this dialogue critically discuss Zeno of Elea's paradox of Achilles and the tortoise. They consider a number of solutions to and restatements of the paradox, together with their philosophical implications. Among the issues investigated include the appearance-reality distinction, Aristotle's distinction between actual and potential infinity, the concept of a continuum, Cantor's continuum hypothesis and theory of transfinite ordinals, and, as a solution to Zeno's puzzle, the distinction between infinite and indeterminate or inexhaustible divisibility.
A low concentration of nisoldipine reduces ischemicheart injury: Enhanced reflow and recovery of contractile function without energy preservation during ischemia

Isolated working rat hearts which received no drug treatment had reduced ATP and creatine phosphate levels and increased lactate content during 20 min of ischemia. When subjected to 33 min of ischemia and 30 min of reperfusion, these hearts recovered low values of cardiac output (9.8 ml/min), heart rate, maximum developed pressure, pressure-rate product (72.9, 32.6, 27.5% of control, respectively), had low levels of tissue ATP, and reduced coronary flow upon reperfusion. Addition of nisoldipine (1 nM) 10 min before ischemia caused no decrease in cardiac output or heart rate, slightly decreased maximum developed pressure and pressure-rate product (93% of control), and did not reduce the degradation of ATP and creatine phosphate or the accumulation of lactate during 20 min of ischemia. When nisoldipine was included 10 min before ischemia, during ischemia (33 min) and reperfusion (30 min), however, the recovery of cardiac function and tissue ATP levels was significantly increased. This protective effect occurred when drug treated ischemic hearts were reperfused with control buffer, indicating residual effects. The beneficial effects of nisoldipine were not due to changes in afterload or preload (isolated perfused heart), collateral flow (zero flow model), energy preservation during ischemia (little contractile depression, ATP not enhanced during ischemia), or reduced lactate accumulation during ischemia. The beneficial effects were associated with increased coronary flow (31% higher than no drug) during reperfusion, indicating a reduction in the no-reflow phenomenon.
Phytochromes A1 and B1 have distinct functions in the photoperiodic control of flowering in the obligate long-day plant Nicotiana sylvestris.

The obligate long-day plant Nicotiana sylvestris with a nominal critical day length of 12 h was used to dissect the roles of two major phytochromes (phyA1 and phyB1) in the photoperiodic control of flowering using transgenic plants under-expressing PHYA1 (SUA2), over-expressing PHYB1 (SOB36), or cosuppressing the PHYB1 gene (SCB35). When tungsten filament lamps were used to extend an 8 h main photoperiod, SCB35 and SOB36 flowered earlier and later, respectively, than wild-type plants, while flowering was greatly delayed in SUA2. These results are consistent with those obtained with other long-day plants in that phyB has a negative role in the control of flowering, while phyA is required for sensing day-length extensions. However, evidence was obtained for a positive role for PHYB1 in the control of flowering. Firstly, transgenic plants under-expressing both PHYA1 and PHYB1 exhibited extreme insensitivity to day-length extensions. Secondly, flowering in SCB35 was completely repressed under 8 h extensions with far-reddeficient light from fluorescent lamps. This indicates that the dual requirement for both far-red and red for maximum floral induction is mediated by an interaction between phyA1 and phyB1. In addition, a diurnal periodicity to the sensitivity of both negative and positive light signals was observed. This is consistent with existing models in which photoperiodic time measurement is not based on the actual measurement of the duration of either the light or dark period, but rather the coincidence of endogenous rhythms of sensitivity ‐ both positive and negative ‐ and the presence of light cues.
Clinopyroxene–a mineral telescoped through the processes of blueschist facies metamorphism

Textural evolution and compositional variation of clinopyroxenes in Ward Creek metabasites are described. Pyroxenes change, with increasing grade, from finegrained aggregates through fan-shaped medium-grained prisms to blocky coarse crystals. Characteristic features of metamorphic pyroxenes include: (1) the occurrence of coexisting pyroxene pairs, the compositions of which are used to delineate compositional gaps; (2) the existence of large compositional variations of pyroxenes, within a single specimen, which record a considerable span of P and/or T for crystallization; and, (3) the development of compositional trends in single specimens and in three metamorphic zones which are progressive in nature. The first formed clinopyroxene (Jd20Aug65Ac15) in the lower lawsonite zone mimics the composition of relict igneous augite. It changes continuously, with increasing grade, at nearly constant low XJd content towards acmite. At a composition around Jd20Aug30Ac50, the trend turns towards jadeite and intersects a solvus to form two coexisting clinopyroxenes in the middle lawsonite zone. At higher grade, the compositional gap becomes restricted towards the jadeite-omphacite join and clinopyroxene increases in XJd toward jadeite. A reversed compositional trend occurs at higher grade; clinopyroxenes decrease in jadeite component at nearly constant Aug/Ac ratio of 50/50 and finally become omphacite in the uppermost pumpellyite and epidote zones. The Na–Ca pyroxenes, close to the binary join Jd–Ac, occur in the lawsonite- and pumpellyite-zones, ranging from XJd= 1.0–0.30 together with Ab and Qz. The ubiquitous occurrence of aragonite at temperature estimates of 170–240° C by Taylor & Coleman (1968) for these zones does not support the low-temperature extrapolation of the Jd–Ab–Qz curve by Holland (1980). The estimated metamorphic field gradient indicates an inflection point at 7 kbar, 200° C. Below this, blueschist facies metamorphism proceeded under dominant pressure-increase from 4 to 7 kbar at nearly constant temperature, about 150–200° C, whereas at higher grade recrystallization, above the inflection point, the metamorphic temperature increased from 200 to 350° C at nearly constant pressure, about 7–8 kbar. Such an inflection point suggests the depth of underplating of either seamounts or accretionary packages in a subduction zone.
Selection for Resistance to Aphanomyces euteiches in Red Clover

Red clover (Trifolium pratense L.) is known to be a moderate host for Aphanomyces euteiches Drechs. Recently, an isolate of A. euteiches (Ae-572) was observed to be highly virulent on red clover. This research was conducted to determine inheritance of, and select for, resistance to A. euteiches in red clover using an inoculated seedling assay. Resistant and susceptible red clover plants were intercrossed to study the inheritance of resistance. Frequency distributions of resistant and susceptible F 1 plants indicated that resistance to A. euteiches is inherited as a quantitative trait
Effect of actinomycin D on vitamin D-mediated uptake of45Ca by intestinal slices

Vitamin D significantly increases the uptake and transport of calcium in the duodenum of D-deficient rats fed either high or low calcium diets. In previous work by others showing that actinomycin D blocked the effect of vitamin D, low calcium: adequate phosphorus animals were used, leaving unanswered the question as to whether actinomycin D would have a similar effect in animals fed a high calcium: low phosphorus diet. With treatment combining ±vitamin D and ±actinomycin D, slices of duodenum were tested for passivevs. active uptake of calciumin vitro. The transport of calcium across the intestine into blood was measuredin vivo. With regard to intestinal uptake, there was no interaction between actinomycin D and vitamin D in animals fed 1.2% Ca: 0.06% P diet for 20 days before treatment. In those animals fed the 0.02% Ca: 0.3% P diet for the same period of time, actinomycin D reduced the uptake of intestinal slicesin vitro but, when combined with vitamin D, the vitamin significantly enhanced the uptake of calcium, though to a lesser extent, in the presence of the antibiotic. Vitamin D tended to increase the transport of calcium into blood of animals on both diets in the presence or absence of actinomycin D.
Flow cytometric analysis of the effect of phenytoin and its major metabolite on mitogen stimulated mouse spleen cells.

Abstract The in vitro immunopharmacological effects of phenytoin (PHT) and its major metabolite 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH) were investigated by flow cytometric analysis of the DNA content of mitogen stimulated mouse spleen cells. The qualitative effects of PHT and HPPH were similar in concanavalin A stimulated mouse spleen cells with both compounds causing an increase in the percentage of S phase cells. The data suggests that this effect is due to an augmentation of cell cycling as demonstrated by the significant increase in 4N cells in PHT treated cultures relative to control cultures following colcemid treatment. A PHT time course study revealed an increase in S phase cells and a subsequent increase in 4N cells. PHT had no significant effect on congenitally athymic nude mouse spleen cells stimulated with lipopolysaccharide (LPS) except at the highest concentration tested (80 μg/ml) where a depression of cell cycling was observed. HPPH caused a colcemid-like accumulation of 4N cells in the LPS stimulated nude mouse spleen cell cultures. PHT and HPPH were found to be effective in enhancing cell cycling in cultures containing a significant population of T-cells stimulated with a T-cell mitogen whereas an inhibitory effect was observed in cultures without T-cells stimulated with a B-cell mitogen. The capacity of PHT to enhance the mitogenic action of concanavalin A may relate to its capacity to induce immunologic abnormalities and lymphadenophathy in humans.
James Ewing: Cancer man

To a large extent, the progress in understanding, diagnosing and treating cancer is the story of individuals: James Ewing was one of the giants. In spite of personal tragedy and infirmities he rose to become the leading tumor pathologist of his time and to head the nation's first cancer center in New York.
Explaining the absence of international factor-price convergence

Abstract As capital markets have become integrated, factor prices have not converged as expected. This paper provides an explanation. The key observation is that non-specific output risks are borne by capital, making international portfolio diversification a dominant strategy. Capital market integration can elicit many patterns of factor-price response under this circumstance. Factor prices will move in parallel if countries are identical; when countries differ, factor prices may diverge, or even have their relative sizes reversed. The integration of capital markets affects welfare through changes in risk and in overall returns to savings: welfare need not improve.
Solid-state travelling-wave amplifiers based on multistream instability

Abstract A method for the amplification of microwaves, based on the space-charge interaction of electron streaming sheets with different velocities in a semiconductor, is described. An n+-n-n+ GaAs diode is used to generate these electron streams. We considered here electron-charged sheets, each of which has a different average velocity due to the doping concentration gradient along the thickness direction in the semiconductor. A dispersion relation is obtained for space-charge waves in the semiconductor, and a numerical analysis is used to calculate the propagation constant γ.The possibility of a growing wave is examined and it is found that a maximum 18 dB gain in the 3-90 GHz band can be achieved.
Identifying reusable resources in digital reference answers

What can we learn from resources provided in answers to digital reference questions? Using the Internet Public Library's archive of over 60,000 records of answered reference questions, this project aims to determine (1) characteristics of resources provided in answers to digital reference questions, (2) the extent to which these resources are reusable in future answers, and (3) the useful lifespan of a resource that has been provided. As part of our research, we have developed an XML schema for digital reference questions and answers.
Insights into E3 ligase activity revealed by a SUMO–RanGAP1–Ubc9–Nup358 complex

SUMO-1 (for small ubiquitin-related modifier) belongs to the ubiquitin (Ub) and ubiquitin-like (Ubl) protein family. SUMO conjugation occurs on specific lysine residues within protein targets, regulating pathways involved in differentiation, apoptosis, the cell cycle and responses to stress by altering protein function through changes in activity or cellular localization or by protecting substrates from ubiquitination. Ub/Ubl conjugation occurs in sequential steps and requires the concerted action of E2 conjugating proteins and E3 ligases. In addition to being a SUMO E3, the nucleoporin Nup358/RanBP2 localizes SUMO-conjugated RanGAP1 to the cytoplasmic face of the nuclear pore complex by means of interactions in a complex that also includes Ubc9, the SUMO E2 conjugating protein. Here we describe the 3.0-A crystal structure of a four-protein complex of Ubc9, a Nup358/RanBP2 E3 ligase domain (IR1-M) and SUMO-1 conjugated to the carboxy-terminal domain of RanGAP1. Structural insights, combined with biochemical and kinetic data obtained with additional substrates, support a model in which Nup358/RanBP2 acts as an E3 by binding both SUMO and Ubc9 to position the SUMO-E2-thioester in an optimal orientation to enhance conjugation.
New Slants on the Slippery Slope: The Politics of Polygamy and Gay Family Rights in South Africa and the United States

This article investigates the often cited and dismissed, but rarely examined, relationship between legalizing same-sex marriage and polygamy. Employing a comparative historical analysis of U.S. and...
Plasticity and canalization in the control of reproduction in the lubber grasshopper.

SYNOPSIS. The ability to change reproductive tactics during adult development in response to environmental variation is predicted to enhance fitness. Many organisms show phenotypic plasticity early in nonembryonic development, but later exhibit phases of developmental inflexibility ( 5canalization). Therefore, we studied reproduction-related hormones and proteins and their relationships to plasticity in the Eastern lubber grasshopper. Diet-switching experiments demonstrated plasticity early in the egg production cycle, but a switch to canalization late in the cycle. We measured developmental titers of 4 hemolymph compounds from single individuals from adult molt until first oviposition. These 4 compounds were the egg-yolk precursor protein vitellogenin, juvenile hormone (the central regulator of insect reproduction), major hemolymph proteins, and ecdysteroids (the arthropod molting hormone that ultimately is stored in the egg). Using diet manipulations, we investigated how these developmental titers relate to the switch from plastic to canalized egg production. All 4 hemolymph compounds reached their peak levels during the canalized phase, about 12 day before oviposition. Diet switches after these peak levels did not affect the timing to oviposition. Therefore, these peak titers were physiological events that occurred after the individual committed to laying. We compared these patterns in reproduction to the development toward adult molt, another major lifehistory event in insects. We observed an extended canalized phase before the adult molt. This canalized phase always included a peak of ecdysteroids. The similar patterns in the physiology of these life-history events suggested that common limitations may exist in major developmental processes of insects that are directed by hormones.
Development of a theoretical model of nickel(II) tris(oxime)amine dichloride with comparison to X-ray crystallography and vibrational spectroscopy

Using modern density-functional theory and vibrational spectroscopy, various theoretical models are evaluated for application to Ni(TRISOXH 3 )Cl 2 . the precursor to a novel oxygen-activating complex. Geometry optimizations and frequency calculations were performed using Gaussian 98 at the Hartree-Fock and B3LYP theory levels. Theoretical data are compared to the published X-ray crystal structure and to vibrational spectra obtained using Raman and infrared methods. The geometry closest to the crystal structure resulted from B3LYP/6-31G(d) & 6-311++G(d,p), where the higher basis set was applied to the metal center. This gas-phase model has a 1.0% average deviation from the experimental bond distances in the solid-phase structure. A lower level calculation (B3LYP/6-31G(d) & 6-311+G(d), again with the higher basis set applied to the Ni) yields vibrational frequencies that are as accurate as the higher level calculation. Three isotope-substituted TRISOXH 3 ligands were synthesized (with 1 5 N amine, 1 5 N oximes, or deuterated oximes); the isotope shifts observed in the vibrational spectra of the Ni complexes were compared to the theoretical shifts. With this empirical information, 28 key normal modes of the vibrational spectra were assigned. A modified wavenumber-linear scaling procedure was applied to the assigned theoretical wavenumbers and yielded a 3-fold improvement in absolute deviation from experimental frequencies over the unscaled values.
Brownian diode: Molecular motor based on a semi-permeable Brownian particle with internal potential drop

Abstract A model of an autonomous isothermal Brownian motor with an internal propulsion mechanism is considered. The motor is a Brownian particle which is semi-transparent for molecules of surrounding ideal gas. Molecular passage through the particle is controlled by a potential similar to that in the transition rate theory, i.e. characterized by two stationary states with a finite energy difference separated by a potential barrier. The internal potential drop maintains the diode-like asymmetry of molecular fluxes through the particle, which results in the particleʼs stationary drift.
Electrical measurements in reaction zones of high explosives

Electrical conductivity profiles with nanosecond and subnanosecond time resolution have been determined for some condensed high explosives using a dynamic conductivity cell. Three explosives are treated in detail, namely, nitromethane, Composition B, and liquid TNT. Each explosive presents a somewhat different conductivity profile as well as a different value for the peak conductivity. The peak conductivity for nitromethane is about 160 mhos per meter, and the peak occurs between 1.5 and 2 nsec behind the detonation front. The conductivity thereafter decreases to a nearly constant value of about 135 mhos per meter, falling off only slightly in the Taylor wave. The conductivity of Composition B, on the other hand climbs steadily, reaching a peak value of 1100 mhos per meter between 80 and 100 nsec after passage of the detonation front. Liquid TNT reaches peak conductivity about 20 nsec after the passage of detonation, front, even though the peak value of the conductivity is nearly an order of magnitude higher than that of Composition B. The profile experiments show that it is unlikely that a single value of the conductivity for detonation products is meaningful. However, the curves of conductivity as a function of time do have certain similarities in their shapes. If the conductivities at corresponding points on each curve, say the maximum, are compared, a strong correlation with the available estimates of the density of solid carbon in the detonation products is evident. This leads to the hypothesis that, in carbon rich explosives, conduction is principally by a continuous network of solid carbon particles.
Vulvar Edema in a Pregnant Adolescent

Abstract We report a case of a pregnant adolescent female with vulvar edema as the initial presentation of nephrotic syndrome. Though adolescents with symptoms related to the genitalia are often presumed to have a sexually transmitted disease, this case illustrates that other conditions should also be considered. The differential diagnosis of vulvar edema is discussed.
Photochemical reactions of some Co(III) and Cr(III) complexes

Abstract Studies have been made of the photochemistry of aqueous Co(NH3)6+3, Co(NH3)5X+2 (X = SCN, Cl, I), Co (CN)5X−3 (X = CN, Cl, Br, I), Co (C2O4)3−3, Cr(NH3)5SCN+2, Cr(NH3)2 (SCN)4−, and Cr (C2O4)3−3. Quantum yields were obtained for the redox decompositions, aquation, or racemization processes that occurred, usually for two wave lenghts, one in the ligand field band region, and one in the electron transfer band region of the absorption spectra. In addition, quantum yields were obtained for the photochemically induced oxidation of iodide ion in the presence of Co(NH3)6+3 and Co(NH3)5Cl+2. The results are interpreted to indicate that the chemical nature of the excited state is qualitatively independent of the wave lenght of the light used. In the other hand, the net consequence of light absorption depends upon which of several possible courses is taken subsquent to the formation of the primary excited state.
P3: Computational environment to support design collaboration

Abstract The work reported in this paper addresses the paradoxical state of the construction industry (also known as A/E/C, for Architecture, Engineering and Construction), where the design of highly integrated facilities is undertaken by severely fragmented teams, leading to diminished performance of both processes and products. The construction industry has been trying to overcome this problem by partitioning the design process hierarchically or temporally. While these methods are procedurally efficient, their piecemeal nature diminishes the overall performance of the project. Computational methods intended to facilitate collaboration in the construction industry have, so far, focused primarily on improving the flow of information among the participants. They have largely met their stated objective of improved communication, but have done little to improve joint decision-making, and therefore have not significantly improved the quality of the design project itself. We suggest that the main impediment to effective collaboration and joint decision-making in the A/E/C industry is the divergence of disciplinary `world-views', which are the product of educational and professional processes through which the individuals participating in the design process have been socialized into their respective disciplines. To maximize the performance of the overall project, these different world-views must be reconciled, possibly at the expense of individual goals. Such reconciliation can only be accomplished if the participants find the attainment of the overall goals of the project more compelling than their individual disciplinary goals. This will happen when the participants have become cognizant and appreciative of world-views other than their own, including the objectives and concerns of other participants. To achieve this state of knowledge, we propose to avail to the participants of the design team highly specific, contextualized information, reflecting each participant's valuation of the proposed design actions. P3 is a semantically-rich computational environment, which is intended to fulfill this mission. It consists of: (1) a shared representation of the evolving design project, connected (through the World Wide Web) to (2) individual experts and their discipline-specific knowledge repositories; and (3) a computational project manager makes the individual valuations visible to all the participants, and helps them deliberate and negotiate their respective positions for the purpose of improving the overall performance of the project. The paper discusses the theories on which the three components are founded, their function, and the principles of their implementation.
The effects of spawning age distribution on salmon persistence in fluctuating environments

Summary 1 Understanding the role endogenous vs. exogenous forces play in determining the dynamics and abundance of natural populations has important implications for their conservation. 2 Changes in environmental conditions often have different effects on closely related species. For instance, recent studies show that a physical shift in ocean conditions in the mid-1970s in the California current have reduced coho salmon (Oncorhynchus kisutsch) populations, but not chinook salmon (O. tshawytscha). 3 An important question is whether this pattern is due to differences in the ability of coho and chinook salmon to respond to changing ocean conditions or to differences in their life-history traits. 4 We analysed a series of population models to test whether observed abundance patterns of coho and chinook salmon could be explained by one of the major differences in their life history, the spawning age distribution; in the California current, female coho salmon are considered to be obligate semelparous, spawning at age 3, while chinook salmon are considered indeterminate semelparous, with populations spawning over a range of ages. 5 Results from a deterministic model indicate that the sensitivity of the population growth rate to changes in ocean survival depends little on the spawning age structure, especially when the growth rate is small (λ ≈ 1). 6 Analysis of linear and non-linear stochastic models indicate that the probability of persistence increases with the width of the spawning age distribution, as the fraction of adults spawning at age 3 decreases from 100% to 95%. Further increases in the spawning age distribution have negligible affects on persistence. 7 Because coho salmon are not absolutely obligate semelparous (e.g. as many as 25% of males can spawn precociously at age 2 and their effect on annual reproduction is unknown), this range of sensitivity does not provide a firm basis for assuming that the observed abundance patterns of coho and chinook is due to differences in their spawning age distribution. 8 While other life-history differences could play a role, we recommend that ongoing field studies focus on the different effects changing ocean conditions have on the survival of individual salmon species.