NVM has commonly been used to address increasingly large last-level caches (LLCs) requirements by reducing leakage. However, frequent data-writing operations result in increased energy consumption. ...In this context, a promising memory technology, Non-volatile SRAM (nvSRAM), enables normal and standby operation modes which can be used to store various types of data. However, nvSRAM suffers from high dynamic energy usage due to frequent switching between operation modes. In this paper, we propose a redundant store elimination (RSE) scheme which, on average, discards 94% of needless bit-write operations. Moreover, we present a retention-aware cache management policy to reduce data updates of cache blocks, based on the correlation between data lifetime and cache types. Experimental results demonstrate that our proposal can improve energy consumption of SRAM-based and RRAM-based LLCs by 57% and 31%, respectively.
This study was designed to determine the effects of 17β-estradiol (E
2) in overcoming the cardiac over-loading and cardiac fibrosis in rats. E
2 (100 ng/kg) or oil was applied in female ...Sprague–Dawley rats with or without bilateral ovariectomy and with or without coarctation of the abdominal aorta after 4 or 8 days. By post-operative day 4, the heart weight, the left ventricular weight, the latent form of MMP-2 in rat hearts with or without the ovary intact had significantly increased while these changes were reversed after E
2 treatment. Although animals with the ovaries intact overcame the hypertrophic effects and the consumption of MMP-2, these effects were not restored in ovariectomized animals in which more fibrosis could be found by day 8. Among the IGF-I signaling, the levels of IGF-I, the activities of PI3K–Akt for cardiomyocyte survival, and MEK–ERKs for non-cardiomyocyte proliferation pathways had significantly increased by day 4. These increasing trends were enhanced by E
2 treatment. However, down-regulation was only observed on day 8 in ovariectomized animals. Similarly, elevated expressions of the steady-state mRNA of IGF-I, IGF-IR, and Cox vb were observed on day 4 in animals with the ovaries intact and these expressions were enhanced by E
2 treatment. In contrast, down-regulation on day 8 in ovariectomized animals was not enhanced by E
2. The calcineurin/NFAT-3 pathway was suppressed on day 4 but was elevated on day 8 in ovariectomized animals. These findings indicate that signaling pathways may be plausible mechanisms for the cardiac protective effects of E
2 administration.
Endotoxemia causes several hematological dysfunctions, including platelet degranulation or disseminated intravascular coagulation, which lead to thrombotic and hemorrhagic events. Here, we tested the ...hypothesis that bacterial lipopolysaccharide (LPS)-stimulated leukocytes contribute to platelet aggregative dysfunction, and this function is attenuated by antioxidants. Plateletrich plasma (PRP) was prepared from whole blood of normal and endotoxemic rats. The ability of platelet aggregation was measured by an aggregometer. LPS (50–100 μg/mL) was incubated with PRP, whole blood and PRP with polymorphonuclear leukocytes (PMNs) for 30 minutes, 60 minutes and 90 minutes, and platelet aggregation was detected. LPS-induced platelet aggregative dysfunction was undetectable in intact PRP which was isolated from normal whole blood, whereas it was detected in PRP isolated from endotoxemic rats and LPS-treated whole blood. Moreover, the effect of LPS-induced platelet aggregative dysfunction on intact PRP was observed when the PMNs were added. LPS-induced platelet aggregative dysfunction was significantly attenuated by catalase alone and in combination with NG -nitro-L-arginine methyl ester, but not by NG -nitro-L-arginine methyl ester alone. These results indicate that LPS-stimulated PMNs modulate platelet aggregation during LPS treatment and the effects are reversed by antioxidants. PMNs serve as an approach to understand LPS-induced platelet aggregative dysfunction during endotoxemia. During this process, the generation of reactive oxygen species, hydrogen peroxide especially, from LPS-stimulated PMNs could be an important potential factor in LPS-induced platelet aggregative dysfunction. Catalase contributes to the prevention of platelet dysfunction during LPS-induced sepsis.
We investigated the effect of vitamin E on membrane protein thiols under oxidative stress, which we induced by treating hepatocytes with tert-butyl hydroperoxide (TBH) for 60 mins. Those cells which ...we pretreated with vitamin E formed fewer blebs (22.3% compared to 60.0% in nonvitamin E-treated cells) and maintained cytosolic calcium concentration and the number of membrane protein thiols instead of showing the usual symptoms in cells undergoing oxidative stress. Dithiothreitol (DTT) also commonly reduces bleb formation in hepatocytes affected by TBH. However, our experiments clearly demonstrate that DTT does not prevent the changes in cytosolic calcium and membrane protein thiols in the blebbing cells. Consequently, we decided to pretreat cells with both DTT and vitamin E and found that the influence of TBH was entirely prevented. These findings may provide us with a new aspect for investigating the mechanism of bleb formation under oxidative stress.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
This study adopts the fuzzy control theory to design a self-tuning fuzzy controller (STFC), which allows adjustment to overcome the controller design difficulty caused by switched reluctance motor ...(SRM) nonlinearity. Based on the torque sharing function (TSF), the proposed STFC was implanted into an SRM direct torque control (DTC) drive system to develop a system with superior speed and electromagnetic torque dynamic responses. In addition, the control strategy possessed excellent electromagnetic torque response, and effectively improved the dynamic response of the system. Keywords: fuzzy control theory, switched reluctance motor (SRM), torque sharing strategy.
This study implemented fuzzy control theory with a cerebellar controller to design a fuzzy cerebellar model articulation controller (FCMAC), ensuring system stability by deriving an adaptive FCMAC ...weight update rule from the Lyapunov theory. The speed estimator design in this study is based on the structure of an adaptive stator flux observer (ASFO) to achieve rapid sensorless control. According to results from experiments, installing the adaptive FCMAC speed controller in the induction motor’s direct torque control system demonstrates excellent speed dynamic response.
The purpose of this study was to develop a hybrid fuzzy-sliding controller with fuzzy self-tuning (HFSC). This controller used a fuzzy supervisory system to allocate the output proportions of a ...sliding-mode controller and a fuzzy controller (FC). The sliding-mode controller primarily provides rapid control efforts in the transient state, and the FC mainly offers smooth control in the steady state and decreases the chatter phenomenon caused by the sliding-mode controller. Finally, the proposed HFSC was implemented in the vector controlled drive system of induction motor as the speed controller. The experimental results showed that the tracking performance and effects of the HFSC were superior to those of the FC.
This study was designed to investigate the alterations of individual protein kinase C (PKC) isoforms in human liver cancer. Surgical specimens of hepatocellular carcinoma and adjacent normal tissues ...were extracted into cytosolic and membranous fractions. The level of membrane-bound PKCα in the cancer tissue was significantly lower than that in the adjacent normal tissue and consistent with the change in PKC activity. In addition, there was a significant negative correlation between PKCα and tumor size. In both cytosolic and membrane fractions, levels of PKCδ and PKCζ was significantly higher in the cancer tissue than those in the adjacent normal liver tissue. The alterations in the PKC isoforms signify their roles in the hyperproliferation in liver cancer.
The ionic mechanisms and cytoprotective activities of 4‐piperidinomethyl‐2‐isopropyl‐5‐methylphenol (THPI), an analogue of thymol, were investigated in HL‐60 granulocytes and in human erythrocytes, ...respectively. THPI inhibited K+ outward current (IK) in a concentration‐dependent manner in HL‐60 leukocytes, with an IC50 value of 4 μM. Neither iberiotoxin (200 nM) nor paxilline (1 μM) suppressed the amplitude of IK, whereas clotrimazole (5 μM) significantly inhibited it. In the inside‐out configuration of single channel recordings, application of THPI (5 μM) into the bath medium did not alter the single‐channel conductance of intermediate‐conductance Ca2+‐activated K+ (IKCa) channels (i.e KCa3.1 channels), but it suppressed the channel activity significantly. THPI‐induced inhibition of IKCa channels was reversed by a further application of 1‐ethyl‐2‐benzimidazolinone (10μM). THPI‐induced reduction in IKCa‐channel activity in these cells was primarily due to a decrease in mean open time. These results provide direct evidence that THPI is capable of suppressing the activity of IKCa channels in HL‐60 cells. The antioxidant action of THPI also revealed a beneficial cytoprotective effect against mitomycin C‐mediated haemolytic effect in human erythrocytes. The results of this study suggest that blockade of IKCa channels and the membrane‐protecting activity of THPI would combine to have beneficial effects in lessening the severity of haemolytic crisis and reducing anaemia in sickle cell disease.
PDF
