In vitro binding of pentobarbital sodium--a component of nembutal--to human blood serum albumins

Comparisons were made of the sexual behaviour of sham-operated male hamsters and castrated males receiving testosterone, dihydrotestosterone or androstenedione (1-5 mg/week), or oil alone. Tests of short duration (10 min) were conducted at Week 3 (when the animals were sexually naive), Week 6 and Week 9. Sham-operated males showed marked increases in many elements of behaviour between Weeks 3 and 9, while castrated males receiving no androgen replacement showed marked decreases. Males receiving each of the three androgens showed marked increases in behaviour, but androstenedione-treated males showed less facilitation of sexual behaviour than controls. Dihydrotestosterone was as effective as testosterone. The three androgens were comparable in maintaining seminal vesicle weight after castration and in preventing the customary rise in pituitary and body weights. These data suggest that, unlike the situation in the rat, aromatization of androgens is unnecessary for the display of sexual behaviour in the hamster.     

Mechanism of NaCl and water reabsorption in the proximal convoluted tubule of rat kidney

The role of chloride concentration gradients in proximal NaCl and water reabsorption was examined in superficial proximal tubules of the rat by using perfusion and collection techniques. Reabsorptive rates (Jv), chloride concentrations, and transtubular potential difference were measured during perfusion with solutions (A) simulating an ultrafiltrate of plasma; (B) similar to (A) except that 20 meq/liter bicarbonate was replaced with acetate; (C) resembling late proximal fluid (glucose, amino acid, acetate-free, low bicarbonate, and high chloride); and (D) in which glucose and amino acids were replaced with raffinose and bicarbonate was partially replaced by poorly reabsorbable anions (cyclamate,sulfate, and methyl sulfate). In tubules perfused with solutions A and B, Jv were 2.17 and 2.7 nl mm-1 min-1 and chloride concentrations were 131.5 +/- 3.1 and 135 +/- 395 meq/liter, respectively, indicating that reabsorption is qualitatively similar to free-flow conditions and that acetate adequately replaces bicarbonate. With solution C, Jv was 2.10 nl mm-1 min-1 and potential difference was +1.5 +/- 0.2 mV, indicating that the combined presence of glucose, alanine, acetate, and bicarbonate per se is not an absolute requirement. Fluid reabsorption was virtually abolished when tubules were perfused with D solutions; Jv was not significantly different from zero despite sodium and chloride concentrations similar to plasma; chloride concentration was 110.8 +/- 0.2 meq/liter and potential difference was -0.98 mV indicating that chloride was close to electrochemical equilibrium. These results suggest the importance of the chloride gradient to proximal tubule reabsorption in regions where actively reabsorbable solutes (glucose, alanine, acetate, and bicarbonate) are lacking and provide further evidence for a passive model of NaCl and water transport.     

The human placenta's lead level as a parameter of the ecological lead exposure. Its validity in comparison to the lead level in blood, the activity of the delta-aminolevulinic acid dehydratase and the concentration of the free erythrocyte porphyrins of newborns and their mothers (author's transl)

In order to estimate the ecological exposure of lead, placenta- and blood-investigations were made at four collectives from variously industrialized regions (Ruhrregion, Middle Frankonia Centre, Bavarian Forest). 148 normal births and 19 premature births (in each case mothers and newborns) were listed as well as twelve abortions. We investigated the lead-level in blood, the activity of delta-aminolaevulinic acid dehydratase (ALA-D) the concentration of free erythrocyte porphyrine (FEP) and the placentas' lead concentration. Though in the Ruhrregion (Dortmund) significantly higher lead levels in blood were found compared to the Bavarian Forest, the results together, were in the normal range, less than 35 mug%. In an average the mothers' lead level in blood was around 1.4 times (ca. 5 mug%) above that of their newborns; analysing this statistically, highly significant correlations were found. However for the ALA-D activity and the FEP-results no direct dependence of the lead levels in blood could be found. In the placentas mean lead concentrations between 1.94 mug and 2.23 mug per gram dry-weight (30.6 mug-38.9 mug/100 g wet-weight) were gained. In the contrary to the measured results of lead in blood the average placentas' lead level of the most and least industrialized regions were almost identical. A correlation between the mothers' respectively their children's lead levels in blood and the placental lead concentrations could not be proved. No relation could be found between the results and the gestation ages. As final results: 1. The placenta is no ideal investigation object concerning the environment's lead exposure. 2. It has no special barriere - or depot - function in lead metabolism. 3. In order to estimate the environment's lead exposure the determination of the lead level in blood will also be in future the optimal method. This investigation is of special value because of its validity of the results and the practicability of winning the samples compared to other parameters and biological materials.     

On the influence of the natriuretic factor from patients with chronic uremia on the bioelectric properties and sodium transport of the isolated mammalian collecting tubule

A gel filtration fraction of urine from patients with chronic renal disease (natriuretic factor) has been shown previously to cause natriuresis in rats and to inhibit sodium transport in the isolated toad bladder. The effect of this fraction on transtubular potential difference and sodium transport was examined on the isolated perfused cortical collecting tubule of the rabbit. A rapid inhibition of potential difference from -22.5 mV to -12 mV (P less than 0.001) was observed when the fraction was applied to the peritubular surface. This effect was accompanied by a decrease in net sodium flux from 6.29 to 3.21 pmol/cm per s (P less than 0.001). Unidirectional fluxes using isotopic sodium revealed that the inhibition of net sodium transport was due to a decrease in flux from the lumen to the peritubular surface, i.e., an inhibition of active sodium transport. There was no change in sodium flux in the reverse direction. These changes were all rapidly reversed by removal of the fraction from the peritubular surface. The addition of the fraction to the lumen had no effect on potential difference or net sodium flux. Control studies using the same fraction from the urine of normal subjects had no effect on any of the parameters studies. Where both a uremic and a normal fraction were sequentially applied to the peritubular surface of the same tubule, inhibition of potential difference was obtained only with the former. In the light of evidence implicating the collecting duct fraction from normal animals, the data are consistent with the view that the natriuretic factor may be biologically important in the regulation of sodium balance via it's regulatory role in active sodium transport in the collecting tubule.     

Protective effect of Perilla frutescens cv. Chookyoupjaso mutant water extract against oxidative injury in vitro and in vivo

The aim of this study was to elucidate the protective ability of the Perilla frutescens cv. Chookyoupjaso mutant water extract (PFWE) against oxidative injury in vitro and in vivo. In in vitro experiments, our results showed that PFWE indicated the intracellular reactive oxygen species (ROS) scavenging activity as well as cytoprotective effect in SIN-1-treated HepG2 cells. The intracellular ROS scavenging activity of PFWE was 44% at 50 μg/mL, 50% at 100 μg/mL, and 56% at 200 μg/mL. Furthermore, in vivo results showed that treatment with PFWE attenuated the activity of serum alkaline phosphatase (ALP) and lipid peroxidation increased by carbon tetrachloride (CCl₄) and also markedly recovered the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) decreased by CCl₄ in BALB/c mice. GPx activity was elevated almost 3-fold compared to control group at 50 mg/kg of PFWE. The present study suggests that PFWE possesses significant protective effects against oxidative injury.     

Analysis of the root causes of refrigerant-induced noise in refrigerators

Refrigerant-induced noises, which occur irregularly at special thermodynamic cycle conditions, are frequently cited by residential customers who use refrigerators. However, these noises are very difficult to resolve and their root causes cannot usually be exactly identified. In this research, the root causes of the irregular refrigerant-induced noise are estimated through the theories of two-phase flow and bubble dynamics. Also, by using refrigerant-supplying equipment that can continuously supply refrigerant to the test unit at typical cycle conditions, the flow patterns of the evaporator in vertical and horizontal pipes are inspected and their noises are simultaneously measured. Through the observation of the relationship between the flow pattern and the refrigerant-induced noise, the root causes of this irregular refrigerant noise can be identified and verified.     

On the plane contact problem of a functionally graded elastic layer loaded by a frictional sliding flat punch

This article is concerned with the contact mechanics of a functionally graded layer loaded by a frictional sliding flat punch. The coefficient of friction is assumed to be constant and the lower side of the graded layer is firmly attached to a rigid foundation. The graded, nonhomogeneous property of the medium is represented in terms of an exponential variation of the shear modulus, while Poisson’s ratio is taken to be constant. Based on the use of plane elasticity equations and the Fourier integral transform technique, the formulation of the current contact mechanics problem lends itself to a Cauchy-type singular integral equation of the second kind for the unknown contact pressure, which is solved numerically. As a result, the effects of several parameters, i.e., the material nonhomogeneity, the friction coefficient, the punch width, and Poisson’s ratio, on the distributions of the contact pressure and the in-plane surface stress component are presented.     

A model-based framework for the analysis of team communication in nuclear power plants

Advanced human-machine interfaces are rapidly changing the interaction between humans and systems, with the level of abstraction of the presented information, the human task characteristics, and the modes of communication all affected. To accommodate the changes in the human/system co-working environment, an extended communication analysis framework is needed that can describe and relate the tasks, verbal exchanges, and information interface. This paper proposes an extended analytic framework, referred to as the H-H-S (human-human-system) communication analysis framework, which can model the changes in team communication that are emerging in these new working environments. The stage-specific decision-making model and analysis tool of the proposed framework make the analysis of team communication easier by providing visual clues. The usefulness of the proposed framework is demonstrated with an in-depth comparison of the characteristics of communication in the conventional and advanced main control rooms of nuclear power plants.     

Fermentation of texturized vegetable proteins extruded at different moisture contents: effect on physicochemical,structural, and microbial properties

Food Science and Biotechnology - To investigate the effect of fermentation on texturized vegetable protein (TVP), TVPs extruded at 40 and 50% feed moisture contents (MC) were fermented using...     

Land use and electricity generation: A life-cycle analysis

Renewable-energy sources often are regarded as dispersed and difficult to collect, thus requiring substantial land resources in comparison to conventional energy sources. In this review, we present the normalized land requirements during the life cycles of conventional- and renewable-energy options, covering coal, natural gas, nuclear, hydroelectric, photovoltaics, wind, and biomass. We compared the land transformation and occupation matrices within a life-cycle framework across those fuel cycles. Although the estimates vary with regional and technological conditions, the photovoltaic (PV) cycle requires the least amount of land among renewable-energy options, while the biomass cycle requires the largest amount. Moreover, we determined that, in most cases, ground-mount PV systems in areas of high insolation transform less land than the coal-fuel cycle coupled with surface mining. In terms of land occupation, the biomass-fuel cycle requires the greatest amount, followed by the nuclear-fuel cycle. Although not detailed in this review, conventional electricity-generation technologies also pose secondary effects on land use, including contamination and disruptions of the ecosystems of adjacent lands, and land disruptions by fuel-cycle-related accidents.