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1.
Stacking active layers leads to increased power density and overall higher temperatures in a three dimensional integrated circuit (3DIC). Thermal sensors are therefore crucial for run-time thermal management of 3DICs. A thermal sensor allocation method customized for 3DICs that utilizes ring oscillator based 3D sensors is introduced in this paper. A new 3D thermal map modeling method that facilitates efficient and very fast analyses is embodied in this thermal sensor distribution algorithm. Our results indicate that for a 4-layer stacked 3DIC, consisting of two layers of quad-core processors and one layer of L2 cache and one layer of main memory, less than 3.58% in maximum sensor reading error can be accomplished with a 53× speedup in the thermal evaluation time and thermal sensor distribution algorithm implementation.  相似文献   
2.
Detailed geological and geochemical investigations in the folded belt of the Zagros geosyncline reveal that the source rocks for the very large Asmari oil accumulations may not be the PabdehGurpi and/or Kazhdumi formations as has been suggested; the hydrocarbons are more likely to be indigenous to the Asmari. Most previous investigators have assumed that only organic-rich marls and shales serve as effective source rocks. However, geochemical analysis shows that the organic content of the Asmari carbonate, although not very rich, compares favourably with the source beds proposed by earlier workers.
A rock should not be considered an oil source bed if it does not currently contain at least traces of oil. If the oil had been generated in the Pabdeh-Gurpi and/or Kazhdumi formations, some hydrocarbons should still be present within these rocks.
For all source rocks, there must be a positive relationship between thermal history and oil generation. Consequently, temperature and depth of burial are essential factors in petroleum genesis. The temperature history of the Asmari Formation is related to the thickness of the overlying Teritiary rocks. Maximum burial of the oligo-Miocene Asmari, throughout most of the folded belt, is assumed to have occured during Early Pliocene time before the last phase of Zagros orogeny.
Asmari limestone, therefore, qualifies as a source rock where it is buried deep enough to reach the optimum temperature needed to release its hydrocarbons. Under conditions of lower temprature and shallower burial, the limestones serve only as reservoir rocks.  相似文献   
3.
A universal joint also known as universal coupling, U joint, Cardan joint, Hardy-Spicer joint, or Hooke??s joint is a joint or coupling in a rigid rod that allows the rod to ??bend?? in any direction, and is commonly used in shafts that transmit rotary motion. It consists of a pair of hinges located close together, oriented at 90° to each other, connected by a cross shaft. The Cardan joint suffers from one major problem: even when the input drive shaft rotates at a constant speed, the output drive shaft rotates at a variable speed, thus causing vibration and wear. The variation in the speed of the driven shaft depends on the configuration of the joint. Such configuration can be specified by three variables. The universal (Cardan) joints are associated with power transmission systems. They are commonly used when there needs to be angular deviations in the rotating shafts. It is the purpose of this research to study the dynamics of the universal joints and to propose some practical methods for improving their performance. The task is performed by initially deriving the motion equations associated to the universal joints. That is followed by elaborating on the oscillatory behavior in the rotational speed and the torque that transmits through the intermediary shaft. The forces in the joint bearings are calculated by using an analytical method that is also supported by the numerical modeling. Such models are also used in order to calculate the rhythm and the amount of the excess loads on the joint. This is suggested as a systematic procedure in the search for the causes of the failures in these popular bearings. With the same purpose in mind some defected bearings with deformed sections were selected for the laboratory examinations. By analyzing the loading behavior and the surface conditions of the defected bearings and by comparison with the known fatigue theories attempts are made in order to dig into the causes for the failures in these joints and their bearing surfaces. With the aim of improving the performance and the life expectancy of these popular elements of the machineries, some practical recommendations are also suggested.  相似文献   
4.
Omeprazole induces CYP1A in the human liver and gut, which has led to concern about possible side effects. The purpose of this study was to compare the effects of omeprazole on phase 1 and phase 2 enzymes in the rat and human. Male rats were treated with intraperitoneal (40 or 80 mg/kg) or oral omeprazole (40 mg/kg) for 5 or 14 days, respectively. The activities and amounts of CYP1A, uridine diphosphate-glucuronosyltransferase, and glutathione transferase were determined in liver and gut. Enzyme activities were also determined in duodenal biopsy specimens from six healthy human volunteers before and after treatment with omeprazole (20 mg/day) for 10 days. Treatment with intraperitoneal omeprazole (40 mg/kg; 80 mg/kg) coinduced uridine diphosphate-glucuronosyltransferase (36%; 66%), glutathione transferase (22%; 50%), and CYP1A (26%; 50%) in rat liver. In rat small intestine, comparable levels of induction were observed for uridine diphosphate-glucuronosyltransferase and glutathione transferase; CYP1A was unaffected. Oral omeprazole had similar effects. Immunoblotting showed corresponding changes in the amounts of these enzymes. Omeprazole increased the activities of CYP1A (19% to 167%; p = 0.014) and uridine diphosphate-glucuronosyltransferase (11% to 68%; p = 0.04) in the duodenal biopsy specimens of all six human volunteers; glutathione transferase was unaffected. Thus, omeprazole coinduced multiple xenobiotic metabolizing enzymes in the rat and human. The pattern of induction differed in the rat and human, consistent with known differences in genetic regulatory elements in the two species.  相似文献   
5.
Malonyl-CoA binding and malonyl-CoA inhibition of carnitine palmitoyltransferase-1 (CPT-I) were measured in hepatic mitochondria from normal and diabetic rats and in protease-treated mitochondria from fed rats to test the hypothesis that proteolysis represents a mechanism by which diabetes produces changes in the sensitivity of CPT-I to inhibition by malonyl-CoA. As in diabetes, protease treatment increased the apparent Ki values for malonyl-CoA. Palmitoyl-CoA greatly diminished malonyl-CoA specific binding in the mitochondrial system being studied, suggesting strong competition at the malonyl-CoA binding site. Proteolysis decreased capacity for specific binding of malonyl-CoA by 60–80%, but it had no effect on binding affinity. In contrast, the decreased specific binding of malonyl-CoA seen in the diabetic state is accompanied by increased binding affinity. Furthermore, observed Kd values differed from Ki values by a factor of 10 or more, suggesting that measured Kd and Ki may represent different ligand-protein complexes. These data suggest that alterations in inhibition of CPT-I by malonyl-CoA occurring in the diabetic state may involve mechanisms other than simple proteolytic removal of malonyl-CoA binding sites.  相似文献   
6.
During the last decade, we have persistently addressed the question, “how can the innate immune system be used as a therapeutic tool to eliminate cancer?” A cancerous tumor harbors innate immune cells such as macrophages, which are held in the tumor-promoting M2 state by tumor-cell-released cytokines. We have discovered that these tumor-associated macrophages (TAM) are repolarized into the nitric oxide (NO)-generating tumoricidal M1 state by the dietary agent curcumin (CC), which also causes recruitment of activated natural killer (NK) cells and cytotoxic T (Tc) cells into the tumor, thereby eliminating cancer cells as well as cancer stem cells. Indications are that this process may be NO-dependent. Intriguingly, the maximum blood concentration of CC in mice never exceeds nanomolar levels. Thus, our results submit that even low, transient levels of curcumin in vivo are enough to cause repolarization of the TAM and recruitment NK cells as well as Tc cells to eliminate the tumor. We have observed this phenomenon in two cancer models, glioblastoma and cervical cancer. Therefore, this approach may yield a general strategy to fight cancer. Our mechanistic studies have so far implicated induction of STAT-1 in this M2→M1 switch, but further studies are needed to understand the involvement of other factors such as the lipid metabolites resolvins in the CC-evoked anticancer pathways.  相似文献   
7.
THE PRE-ZAGROS INTEGRITY OF THE IRANIAN PLATFORM   总被引:1,自引:0,他引:1  
The Hormoz Formation of InfraCambrian age is the oldest unit recognized in southern Iran. It consists mainly of salt, other evaporites and débris of basement rocks. Some huge blocks of the uppermost PreCambrian and Lower Cambrian layered rocks were lifted to the surface by uprising Hormoz salt.
A detailed field investigation within three major salt diapirs located in the SE segment of the Zagros Fold Belt was carried out. Some lithologic-stratigraphic correlations between three formations within selected salt domes on the western part of the Zagros crush zone, and the equivalent units on the eastern part, are established.
The Permian transgressive sea deposited basinal clastics unconformably on the Devonian in central Iran, and overstepped the basement rocks in central Arabia. The Pecten species of the Lower Jurassic Neyriz Formation of the Zagros Fold Belt can be correlated with the Nayband Formation of central Iran. The Tertiary evaporites of SSW Iran are correlated with the Tertiary evaporites of central Iran.
Evidence discussed indicates the presence of a single tectonic entity with no geologic break between SW Iran and the plateau of Iran in the NE.  相似文献   
8.
CBL/57 strain db/db mice exhibit type II (noninsulin-dependent) diabetes. The affected mice are markedly hyperinsulinemic, hyperglycemic, and hypercholesterolemic, and their serum K+ levels are decreased. The brains of the diabetic mice are significantly smaller than those of their lean, control littermates, but the protein concentration is normal. The low brain weight is accompanied by a loss of major fatty acid components within the whole brain, nerve endings, and mitochondrial membranes. Cholesterol levels are low in whole brain but are not significantly different from normal in the synaptosomal membranes. The phospholipid concentration is significantly decreased in whole brain homogenates, crude synaptosomal membranes, and crude mitochondrial membranes of the diabetic mice. In addition, the specific activities of membrane-bound synaptosomal acetylcholinesterase, Na+,K(+)-ATPase, and Mg(2+)-ATPase are decreased in crude synaptosomal membranes of the diabetic mice. The specific activities of carnitine palmitoyltransferase I and carnitine acetyltransferase are significantly increased in the crude mitochondrial fraction isolated from the brains of the type II diabetic mice, whereas the specific activity of pyruvate dehydrogenase complex is decreased. The specific activities of two other mitochondrial enzymes--monoamine oxidase B and citrate synthase--and a cytosolic enzyme--lactate dehydrogenase--are unaltered. The ability to synthesize cyclic AMP is markedly decreased in the brains of the diabetic mice. The concentrations of carnitine and of the amino acids, glutamate, aspartate, glutamine, and serine are unaltered, whereas glycine levels are significantly elevated in the brains of the db/db mice. The data suggest that in vivo the brains of the diabetic mice exhibit a decreased capacity for glucose oxidation and increased capacity for fatty acid oxidation. This hypothesis is supported by the finding that cerebral mitochondria isolated from the db/db mice oxidize [1-14C]palmitate to 14CO2 at a rate almost twice that of control mitochondria. The present findings emphasize the potentially serious alteration of brain metabolism in uncontrolled type II diabetes.  相似文献   
9.
The Guri Limestone Member of the Mishan Formation of Early to Middle Miocene age produces gas in the SE portion of the Zagros geosyncline. The Mishan Formation, which is predominantly marl in its type section near Khuzestan Province, becomes more argillaceous with an increase in organic content towards the SE where the sequence thickens. In the SE portion of the Zagros geosyncline, the lower part of the Mishan changes to a highly-resistant, fossilqerous limestone which is called the Guri Limestone. This is of Late-Early Miocene age in most of the SE Zagros and rises in stratigraphic position towards the NW, becoming of Middle Miocene age in Khuzestan Province. The Guri thickens considerably with massive reefal-type deposits towards the eastern end of the Fars Province near the Oman high.
Lithological and geochemical studies support the hypothesis that the Mishan Formation could serve as a source rock for the hydrocarbons which have been found within the Guri. However, subsidence has failed to place the Mishan Formation within the thermal zone thought to be necessary for liquid hydrocarbon formation, and it is more likely that the deposits will produce gas.  相似文献   
10.
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