Effects of stimulation on steroid output and perfusion medium flow rate in the isolated perfused rat adrenal gland in situ

1986 ◽  
Vol 109 (2) ◽  
pp. 279-285 ◽  
Author(s):  
J. P. Hinson ◽  
G. P. Vinson ◽  
B. J. Whitehouse ◽  
G. M. Price
Keyword(s):  
Flow Rate ◽  
Zona Glomerulosa ◽  
Clear Correlation ◽  
Perfusion Medium ◽  
Flow Rates ◽  
Vascular Elements ◽  
Medium Flow ◽  
High Concentrations ◽  
Adrenal Vasculature

ABSTRACT Using the in-situ, isolated, perfused rat adrenal system, the actions of adrenal stimulants on steroidogenesis and perfusion medium flow rates (under constant perfusion pump conditions) have been studied. In a series of 100 experiments, initial rates of corticosterone output and flow rates were found to be positively correlated, although there was no such relationship between initial rates of aldosterone output and flow rates. Furthermore, in stable perfusion conditions, bolus injections of ACTH increased both flow rate and steroid output in a dose-related manner. In individual experiments there was a clear correlation between corticosterone and flow, but the association between aldosterone secretion rate and flow was less evident. It is possible that this discrepancy arises because of temporal differences in the responses of these two steroids. Flow was also stimulated by dibutyryl cyclic AMP (dbcAMP), with correlations with steroid output similar to ACTH, but the specific zona glomerulosa stimulants angiotensin II amide and potassium ions had, if anything, inhibitory effects on flow, but only at high concentrations. The data suggest that ACTH and dbcAMP evoke specific responses in the adrenal vasculature, resulting in relatively decreased intraglandular vascular resistance. They furthermore suggest that the secretory functions of the inner adrenocortical zones are subject to the additional control of vascular elements in the intact gland. J. Endocr. (1986) 109, 279–285

Adrenal mast cells modulate vascular and secretory responses in the intact adrenal gland of the rat

1989 ◽  
Vol 121 (2) ◽  
pp. 253-NP ◽  
Author(s):  
J. P. Hinson ◽  
G. P. Vinson ◽  
J. Pudney ◽  
B. J. Whitehouse
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Adrenal Gland ◽  
Flow Rate ◽  
Disodium Cromoglycate ◽  
Perfusion Medium ◽  
Steroid Secretion ◽  
Connective Tissue Capsule ◽  
Medium Flow

ABSTRACT Mast cells were identified in the rat adrenal gland, located in the walls of arterioles at the point at which they penetrate the connective tissue capsule. The mast cell products, histamine and serotonin, both caused dose-dependent increases in rates of perfusion medium flow and steroid secretion in the isolated, perfused rat adrenal gland in situ. Compound 48–80, a mast cell degranulator, caused a significant increase in perfusion medium flow rate and steroid secretion by the in-situ perfused rat adrenal. Administration of disodium cromoglycate, a mast cell stabilizer, before administration of ACTH(1–24) virtually abolished the normal flow rate increment and significantly attenuated the corticosterone secretory response to ACTH(1–24). These observations strongly suggest that adrenal mast cells modulate both vascular and secretory responses in the intact adrenal gland of the rat. Journal of Endocrinology (1989) 121, 253–260

Development of Robust Microvavles for Compact Robust Pumps/Hydraulic Actuators

2007 ◽  
Vol 121-123 ◽  
pp. 1207-1210
Author(s):  
B. Li ◽  
Q. Chen
Keyword(s):  
High Pressure ◽  
Flow Rate ◽  
Pressure Support ◽  
Test Results ◽  
Valve Design ◽  
Standard Process ◽  
Flow Rates ◽  
Forward Flow ◽  
Large Flow

In situ UV-LIGA assembled robust micro check valves with large flow rates (>10 ml/s, displacement related), high-pressure support ability (>10 MPa) and high operational frequencies (>10 kHz) made of nano-structured nickel were presented in this paper. The microvalve consists of an array of 80 single micro valves to achieve the required flow rates. Test results show that the forward flow rate is about 19 ml/s under pressure of 90Psi. The backward flow rate is negligible. The reliability of the valve is ensured by the valve design and nanostructured nickel realized. The tested tensile strength of a nano structured nickel is about 1GPa. The strength of SU-8 is 50MPa, which is more than 50% higher that fabricated with a standard process.

scholarly journals Experimental study of in-situ W/O emulsification during the injection of MgSO4 and Na2CO3 solutions in a glass micromodel

2020 ◽  
Vol 75 ◽  
pp. 87
Author(s):  
Sepideh Palizdan ◽  
Hossein Doryani ◽  
Masoud Riazi ◽  
Mohammad Reza Malayeri
Keyword(s):  
Experimental Study ◽  
Flow Rate ◽  
Oil Recovery ◽  
Deionized Water ◽  
Water Flooding ◽  
Flow Rates ◽  
Glass Micromodel ◽  
The Impact ◽  
Emulsification Process

In-situ emulsification of injected brines of various types is gaining increased attention for the purpose of enhanced oil recovery. The present experimental study aims at evaluating the impact of injecting various solutions of Na2CO3 and MgSO4 at different flow rates resembling those in the reservoir and near wellbore using a glass micromodel with different permeability regions. Emulsification process was visualized through the injection of deionized water and different brines at different flow rates. The experimental results showed that the extent of emulsions produced in the vicinity of the micromodel exit was profoundly higher than those at the entrance of the micromodel. The injection of Na2CO3 brine after deionized water caused the impact of emulsification process more efficiently for attaining higher oil recovery than that for the MgSO4 brine. For instance, the injection of MgSO4 solution after water flooding increased oil recovery only up to 1%, while the equivalent figure for Na2CO3 was 28%. It was also found that lower flow rate of injection would cause the displacement front to be broadened since the injected fluid had more time to interact with the oil phase. Finally, lower injection flow rate reduced the viscous force of the displacing fluid which led to lesser occurrence of viscous fingering phenomenon.

In Situ Nitrogen and Aluminum Doping in Migration Enhanced Embedded Epitaxial Growth of 4H-SiC

2008 ◽  
Vol 600-603 ◽  
pp. 175-178 ◽  
Author(s):  
Adolf Schöner ◽  
Naohiro Sugiyama ◽  
Yuuichi Takeuchi ◽  
Rajesh Kumar Malhan
Keyword(s):  
High Temperature ◽  
Epitaxial Growth ◽  
Flow Rate ◽  
Nitrogen Doping ◽  
High Flow ◽  
Memory Effects ◽  
Aluminum Doping ◽  
Flow Rates ◽  
Aluminum Precursor

The in-situ doping of aluminum and nitrogen in migration enhanced embedded epitaxy (ME3) is investigated with the aim to apply it to the realization and fabrication of all-epitaxial, normally-off 4H-SiC JFET devices. This ME3 process consists of the epitaxial growth of an n-doped channel and a highly p-doped top gate in narrow trenches. We found that the nitrogen doping in the n-channel (a-face) is a factor 1.5 higher than layers grown with the same process on Si-face wafers. Due to the low C/Si ratio and the low silane flow rate used in the ME3 process, the growth of the p-doped top gate needs high flow rates of the aluminum precursor trimethylaluminum for several hours, which contaminates the CVD reactor and causes aluminum memory effects. These aluminum memory effects can be reduced by an extra high temperature bake-out run.

scholarly journals GROWTH RATE DISTRIBUTION OF BORAX SINGLE CRYSTALS ON THE (001) FACE UNDER VARIOUS FLOW RATES

2010 ◽  
Vol 6 (1) ◽  
pp. 16-19
Author(s):  
Suharso Suharso
Keyword(s):  
Growth Rate ◽  
Single Crystals ◽  
Flow Rate ◽  
Flow Rates ◽  
Rate Distribution ◽  
Spss Software ◽  
Log Normal ◽  
Growth Rate Distribution ◽  
Log Normal Distribution

The growth rates of borax single crystals from aqueous solutions at various flow rates in the (001) direction were measured using in situ cell method. From the growth rate data obtained, the growth rate distribution of borax crystals was investigated using Minitab Software and SPSS Software at relative supersaturation of 0807 and temperature of 25 °C. The result shows that normal, gamma, and log-normal distribution give a reasonably good fit to GRD. However, there is no correlation between growth rate distribution and flow rate of solution.   Keywords: growth rate dispersion (GRD), borax, flow rate

The Determination of In-Situ Film Hole Flow Rates Using a Transient Thermal Inertia Method

2003 ◽  
Author(s):  
Ronald S. Bunker ◽  
Sarah J. Osgood ◽  
Nirm V. Nirmalan
Keyword(s):  
Flow Rate ◽  
Internal Heat ◽  
Transient Behavior ◽  
Flow Area ◽  
Local Flow ◽  
Flow Rates ◽  
Discharge Coefficients ◽  
Thermal Transient

Film hole flow rates are conventionally characterized by a discharge coefficient relating the actual mass flow rate to the theoretical ideal flow rate based upon some measured effective hole diameter or flow area. These discharge coefficients are typically measured on controlled test plates that contain the particular size, shape, and fabrication method for an individual film hole type. Such discharge coefficients are then assumed to apply to all of the in-situ film holes of that type which are machined or formed in the as-fabricated cooled turbine component. The thermal-mechanical analysis of the component is then performed using these assumed values to calculate film hole flow rates. In practice however, every film hole in a cooled airfoil is different due to machine tool wear, surface curvatures, laser drift, coating variations, and local flow supply behavior. A new method has been developed and demonstrated which allows determination of the individual film hole flow rates in-situ for an as-fabricated component, thus avoiding the need for assumed discharge coefficients or highly detailed flow checks. This method uses the thermal transient characteristics of external surface points near an active film hole to determine the flow rate through the hole. An imaging Infrared system is used to record the component response to an induced thermal cooling transient in which the film hole internal heat transfer dominates the local thermal transient behavior. The characteristic of the non-dimensionalized thermal decay is related to the flow rate within each individual film hole using a limited calibration function. This method allows the rapid inspection and quantification of detailed film hole flows for actual parts, which data may then be used in the analysis and health monitoring of parts in operation.

scholarly journals Copper Mineralization Potential of Late Triassic Granitoids in Northern Yidun Arc, SW China

Minerals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 337 ◽  
Author(s):  
Xing-Yuan Li ◽  
Jing-Ru Zhang ◽  
Hao Song ◽  
Chun-Kit Lai
Keyword(s):  
Age Dating ◽  
Late Triassic ◽  
Clear Correlation ◽  
Sw China ◽  
Copper Mineralization ◽  
Icp Ms ◽  
High Concentrations ◽  
T Values ◽  
Yidun Arc

Yidun arc is an important constituent of the Sanjiang Tethyan Domain in SW China. The Changdagou pluton, located in the northern part of the Yidun Arc, mainly consists of granodiorite. In this study, we conducted in-situ LA-ICP-MS zircon U-Pb dating, and trace element and Hf isotope analyses on the Changdagou granites. Age dating results yielded a weighted mean U-Pb age of 214.97 ± 0.98 Ma (MSWD = 1.2, 2σ), broadly coeval with extensive late Triassic magmatism across the Yidun Arc. All zircon grains analyzed showed high concentrations of Th, U, and HREE, with positive Ce and negative Eu anomalies. Logfo2 and CeN/CeN* values vary from FMQ −3.14 to FMQ +7.44 (average FMQ +3.98), and 14 to 172 (avg. 98), respectively. The zircon EuN/EuN* (avg. 0.22) ratios have no clear correlation with the CeN/CeN* ratios, suggesting that the former were mainly affected by the magma water content. In addition, zircon εHf(t) values vary in a narrow range (–2.9 to −4.9, avg. −3.4) that clusters around zero, indicating a greater component of mantle-derived magma. Hence, we propose that the Changdagou granodiorite was derived from a highly oxidized, “wet”, Cu-rich source, of the type likely to generate porphyry Cu mineralization. However, these parameters (logfO2, EuN/EuN*, (Ce/Nd)/Y, and εHf(t)) are all lower than those of intrusions associated with Cu ores at Pulang and Lannitang, which may explain why the Cu deposit discovered at Changdagou is small by comparison. Furthermore, on the basis of the decreasing trends of εHf, logfO2, and H2O content from south to north along the Yiduan arc, we infer that the northern segment of the Yidun arc (including Changdagou) was located further away from the subduction front.

ABOLITION OF MAGNESIUM-INDUCED HYPOCALCAEMIA BY ACUTE THYRO-PARATHYROIDECTOMY IN THE CAT

1970 ◽  
Vol 64 (1) ◽  
pp. 150-158 ◽  
Author(s):  
S. Pors Nielsen
Keyword(s):  
Sodium Chloride ◽  
Flow Rate ◽  
Magnesium Chloride ◽  
Calcium Concentration ◽  
Plasma Calcium ◽  
Magnesium Concentration ◽  
Isotonic Sodium Chloride ◽  
Plasma Calcium Concentration ◽  
High Concentrations ◽  
Plasma Magnesium

ABSTRACT Intravenous infusion of isotonic magnesium chloride into young cats with a resultant mean plasma magnesium concentration of 7.7 meq./100 g protein was followed by a significant lowering of the plasma calcium concentration in 90 minutes. The rate of decrease of plasma calcium is consistent with the hypothesis that calcitonin is released by magnesium in high concentrations. There was no decrease in the plasma calcium concentration in cats of the same weight thyroparathyroidectomized 60 min before an identical magnesium chloride infusion or an infusion of isotonic sodium chloride at the same flow rate. The hypercalciuric effect of magnesium could not account for the hypocalcaemic effect of magnesium. Plasma magnesium concentration during magnesium infusion into cats with an intact thyroid-parathyroid gland complex was slightly, but not significantly higher than in acutely thyroparathyroidectomized cats.

New Technologies for Decontamination of Radioactive Substances Scattered by Nuclear Accident / Nowe Technologie Dekontaminacji Radioaktywnych Substancji Rozproszonych Przez Awarie Nuklearna

2013 ◽  
Vol 58 (1) ◽  
pp. 283-290 ◽  
Author(s):  
Y. Nishizaki ◽  
H. Miyamae ◽  
S. Ichikawa ◽  
K. Izumiya ◽  
T. Takano ◽  
...  
Keyword(s):  
Radioactive Waste ◽  
New Technologies ◽  
Ferric Hydroxide ◽  
Nuclear Accident ◽  
Radioactive Cesium ◽  
Cesium Ions ◽  
Naoh Solution ◽  
High Concentrations ◽  
Water Rinsing

Our effort for decontamination of radioactive cesium scattered widely by nuclear accident in March 2011 in Fukushima, Japan has been described. Radioactive cesium scattered widely in Japan has been accumulating in arc or plasma molten-solidified ash in waste incinerating facilities up to 90,000 Bq/kg of the radioactive waste. Water rinsing of the ash resulted in dissolution of cesium ions together with high concentrations of potassium and sodium ions. Although potassium inhibits the adsorption of cesium on zeolite, we succeeded to precipitate cesium by in-situ formation of ferric ferrocyanide and iron rust in the radioactive filtrate after rinsing of the radioactive ash with water. Because the regulation of no preservation of any kind of cyanide substances, cesium was separated from the precipitate consisting of cesium-captured ferric ferrocyanide and ferric hydroxide in diluted NaOH solution and subsequent filtration gave rise to the potassium-free radioactive filtrate. Cesium was captured by zeolite from the potassium-free radioactive filtrate. The amount of this final radioactive waste of zeolite was significantly lower than that of the arc-molten-solidified ash.

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