74 research outputs found
Electronic properties of very thin native SiO2/a-Si:H interfaces and their comparison with those prepared by both dielectric barrier discharge oxidation at atmospheric pressure and by chemical oxidation
The contribution deals with electronic properties of thin oxide/amorphous hydrogenated silicon (a-Si:H) measured by capacitance-voltage (C-V) and charge version of deep level transient spectroscopy (Q-DLTS). The interest was focused on the studies of the interface properties of very thin dielectrics formed by dielectric barrier discharge (DBD) or natively on the a-Si:H layer. These properties were compared with those of oxide layers prepared by chemical oxidation in HNO3. The DBD was used for the preparation of a very thin SiO2 layer on a-Si:H for the first time to our knowledge. Preliminary electrical measurements confirmed that a very low interface states density was detected in the case of the native oxide/a-Si:H and DBD oxide/a-Si:H
HIGH PERFORMANCE ELECTRICALLY EXPLODED FOIL OPENING SWITCHES
Abstract Electrically exploded foil fuses have been employed as high energy opening switches for several years (Ref 1,2). As stored energies evolve into the tens of megajoules and currents rise to near one hundred megamperes , small improvements in fuse performance could have significant effects on the amount of energy transferred to a load . In this paper we examine changes in the parameters of aluminum fuses that produce improved fuse performance when operated without a load. The factors of fuse thickness and fuse quench are seen to affect fuse performance as well as alteration of the fuse mass, length, and width. Those fuses tha t performed the "best" were examined and their result~ analyzed in both the time domain and the specific energy domain
The innate immune response to coxsackievirus B3 predicts progression to cardiovascular disease and heart failure in male mice
<p>Abstract</p> <p>Background</p> <p>Men are at an increased risk of dying from heart failure caused by inflammatory heart diseases such as atherosclerosis, myocarditis and dilated cardiomyopathy (DCM). We previously showed that macrophages in the spleen are phenotypically distinct in male compared to female mice at 12 h after infection. This innate immune profile mirrors and predicts the cardiac immune response during acute myocarditis.</p> <p>Methods</p> <p>In order to study sex differences in the innate immune response, five male and female BALB/c mice were infected intraperitoneally with coxsackievirus B3 (CVB3) or phosphate buffered saline and their spleens were harvested 12 h later for microarray analysis. Gene expression was determined using an Affymetrix Mouse Gene 1.0 ST Array. Significant gene changes were verified by quantitative real-time polymerase chain reaction or ELISA.</p> <p>Results</p> <p>During the innate immune response to CVB3 infection, infected males had higher splenic expression of genes which are important in regulating the influx of cholesterol into macrophages, such as phospholipase A<sub>2 </sub>(PLA<sub>2</sub>) and the macrophage scavenger receptor compared to the infected females. We also observed a higher expression in infected males compared to infected females of squalene synthase, an enzyme used to generate cholesterol within cells, and Cyp2e1, an enzyme important in metabolizing cholesterol and steroids. Infected males also had decreased levels of the translocator protein 18 kDa (TSPO), which binds PLA<sub>2 </sub>and is the rate-limiting step for steroidogenesis, as well as decreased expression of the androgen receptor (AR), which indicates receptor activation. Gene differences were not due to increased viral replication, which was unaltered between sexes.</p> <p>Conclusions</p> <p>We found that, compared to females, male mice had a greater splenic expression of genes which are important for cholesterol metabolism and activation of the AR at 12 h after infection. Activation of the AR has been linked to increased cardiac hypertrophy, atherosclerosis, myocarditis/DCM and heart failure in male mice and humans.</p
Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis
Background
Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy.
Methods
We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance.
Results
We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography.
Conclusion
Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data
Early stroke-related deep venous thrombosis: risk factors and influence on outcome
Deep venous thrombosis (DVT) is a serious complication of various medical conditions including acute stroke. Our aim was to identify the occurrence of early stroke-related DVT, risk factors for its development and the influence on outcome. The study involved consecutive patients admitted to our center due to acute ischaemic (n = 278) or haemorrhagic (n = 12) stroke during a 16-month period. We collected data on their pre-stroke health status, neurological deficit on admission and baseline serum CRP and fibrinogen level. Ultrasonographic imaging was performed at the 3rd (IQR: 2–4) and 9th (IQR: 8–9) day after stroke. Patients thrombosis occurring between the first and second examination comprised the newly developed early stroke-related DVT group. We found DVT in 8.0% (24/299) of patients at initial evaluation. Newly developed DVT was present in 3.0% (9/299) of patients, and was predominantly distal (7 of 9 cases). It was associated with elevated serum CRP level (OR 8.75; 95%CI: 1.61–47.6), which was verified in a model adjusted for stroke severity and pre-stroke dependency (3–5 pts. in mRS). In a multivariate model, newly developed DVT significantly increased the risk of 3-month mortality (OR 12.4; 95%CI: 1.72–89.4), without affecting the combined risk of dependency and death (OR 2.57; 95%CI: 0.39–17.0). Early stroke-related DVT is an infrequent complication. However, it may be an independent risk factor for 3-month mortality. Increased serum CRP level combined with normal fibrinogen level seems predictive for development of DVT. It may be reasonable to provide those patients with additional DVT prophylaxis
Aging-Aware Request Scheduling for Non-Volatile Main Memory
Modern computing systems are embracing non-volatile memory (NVM) to implement
high-capacity and low-cost main memory. Elevated operating voltages of NVM
accelerate the aging of CMOS transistors in the peripheral circuitry of each
memory bank. Aggressive device scaling increases power density and temperature,
which further accelerates aging, challenging the reliable operation of
NVM-based main memory. We propose HEBE, an architectural technique to mitigate
the circuit aging-related problems of NVM-based main memory. HEBE is built on
three contributions. First, we propose a new analytical model that can
dynamically track the aging in the peripheral circuitry of each memory bank
based on the bank's utilization. Second, we develop an intelligent memory
request scheduler that exploits this aging model at run time to de-stress the
peripheral circuitry of a memory bank only when its aging exceeds a critical
threshold. Third, we introduce an isolation transistor to decouple parts of a
peripheral circuit operating at different voltages, allowing the decoupled
logic blocks to undergo long-latency de-stress operations independently and off
the critical path of memory read and write accesses, improving performance. We
evaluate HEBE with workloads from the SPEC CPU2017 Benchmark suite. Our results
show that HEBE significantly improves both performance and lifetime of
NVM-based main memory.Comment: To appear in ASP-DAC 202
Safety of intravenous ferric carboxymaltose versus oral iron in patients with nondialysis-dependent CKD: an analysis of the 1-year FIND-CKD trial.
Background: The evidence base regarding the safety of intravenous (IV) iron therapy in patients with chronic kidney disease (CKD) is incomplete and largely based on small studies of relatively short duration. Methods: FIND-CKD (ClinicalTrials.gov number NCT00994318) was a 1-year, open-label, multicenter, prospective study of patients with nondialysis-dependent CKD, anemia and iron deficiency randomized (1:1:2) to IV ferric carboxymaltose (FCM), targeting higher (400-600 µg/L) or lower (100-200 µg/L) ferritin, or oral iron. A post hoc analysis of adverse event rates per 100 patient-years was performed to assess the safety of FCM versus oral iron over an extended period. Results: The safety population included 616 patients. The incidence of one or more adverse events was 91.0, 100.0 and 105.0 per 100 patient-years in the high ferritin FCM, low ferritin FCM and oral iron groups, respectively. The incidence of adverse events with a suspected relation to study drug was 15.9, 17.8 and 36.7 per 100 patient-years in the three groups; for serious adverse events, the incidence was 28.2, 27.9 and 24.3 per 100 patient-years. The incidence of cardiac disorders and infections was similar between groups. At least one ferritin level ≥800 µg/L occurred in 26.6% of high ferritin FCM patients, with no associated increase in adverse events. No patient with ferritin ≥800 µg/L discontinued the study drug due to adverse events. Estimated glomerular filtration rate remained the stable in all groups. Conclusions: These results further support the conclusion that correction of iron deficiency anemia with IV FCM is safe in patients with nondialysis-dependent CKD
Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial
Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie
Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial
Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials.
Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure.
Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen.
Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049
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