Improving the energy efficiency while guaranteeing quality of services (QoS) is one of the main challenges of efficient resource management of large-scale data centers. Dynamic virtual machine (VM) ...consolidation is a promising approach that aims to reduce the energy consumption by reallocating VMs to hosts dynamically. Previous works mostly have considered only the current utilization of resources in the dynamic VM consolidation procedure, which imposes unnecessary migrations and host power mode transitions. Moreover, they select the destinations of VM migrations with conservative approaches to keep the service-level agreements , which is not in line with packing VMs on fewer physical hosts. In this paper, we propose a regression-based approach that predicts the resource utilization of the VMs and hosts based on their historical data and uses the predictions in different problems of the whole process. Predicting future utilization provides the opportunity of selecting the host with higher utilization for the destination of a VM migration, which leads to a better VMs placement from the viewpoint of VM consolidation. Results show that our proposed approach reduces the energy consumption of the modeled data center by up to 38% compared to other works in the area, guaranteeing the same QoS. Moreover, the results show a better scalability than all other approaches. Our proposed approach improves the energy efficiency even for the largest simulated benchmarks and takes less than 5% time overhead to execute for a data center with 7600 physical hosts.
Risk factors associated with early seizure after cardiopulmonary bypass (CPB) were examined. The role of tranexamic acid in seizure development was evaluated.
Early seizure was defined as a seizure ...occurring within 24 hours of CPB, without neurologic deficit or new lesion on brain imaging. Independent determinants of early seizure were examined by multivariate logistic regression modelling.
Between 2004 and 2009, early seizure occurred in 119 of 8,929 patients (1.3%). A significant increase in the yearly rate of early seizure was observed in 2004 (0.73%) vs 2009 (1.97%; p<0.0001). Multivariate analysis showed the following variables were independent predictors of early seizure: age older than 75 years (adjusted odds ratio OR, 2.1; p=0.0001), open heart procedure (OR, 12.0; p<0.0001), preoperative renal failure (OR, 3.2; p<0.0001), peripheral vascular disease (OR, 1.8; p=0.02), and total tranexamic acid dose of 100 mg/kg or more (OR, 2.6; p<0.0001). Risk of seizure was related to tranexamic acid in a dose-dependent fashion, with higher doses associated with increased risk of seizure. The use of CO2 in a subset of patients undergoing open heart procedures did not decrease the incidence of early seizure (4.8% vs 2.5% for no CO2; p=0.27). Postoperative chest tube drainage and blood product use were similar between patients receiving low-dose and high-dose tranexamic acid.
High-dose tranexamic acid (≥100 mg/kg) is independently associated with an increased risk of early seizure. Future tranexamic acid trials should assess the blood-conserving effect of tranexamic acid at a lower dosage and specifically monitor for seizure occurrence.
Magnetic random access memory is a promising solution to keep up with the trend of memory sizing. On the other hand, the multiple-valued logic has been considered as a promising solution for some ...important challenges of the binary integrated circuits. In this paper, a novel ternary magnetic RAM (TMRAM) based on sub-10 nm gate-all-around carbon nanotube transistor (GAA-CNTFET) is proposed. The proposed TMRAM cell utilizes magnetic tunnel junction (MTJs) to provide non-volatility and spin-hall assisted spin-transfer torque method to reduce the write energy. Moreover, GAA-CNTFETs provide ternary operation and enhance the cell performance and efficiency. The read and write circuitry of the proposed magnetic memory cell contains no sense amplifier and bistable feedback, which makes it invulnerable to radiations effects. The efficiency of the proposed TMRAM cell becomes more apparent in the TMRAM block structures due to the reduction in the number of transistors. The proposed approach is simulated using HSPICE and its performance is evaluated in presence of variations in the critical process parameters of MTJ and GAA-CNTFET by Monte-Carlo simulations. The results indicate the correct and efficient operation of the proposed design even in the presence of different process variations.
Paradigm shifts in alternative access for transcatheter aortic valve replacement: An update Junquera, Lucía; Kalavrouziotis, Dimitri; Dumont, Eric ...
Journal of thoracic and cardiovascular surgery/The Journal of thoracic and cardiovascular surgery/The journal of thoracic and cardiovascular surgery,
April 2023, 2023-04-00, 20230401, Letnik:
165, Številka:
4
Journal Article
The Society of Thoracic Surgeons Database was queried to ascertain current trends in management of tetralogy of Fallot (TOF) and to determine the prevalence of various surgical techniques.
The study ...population (n = 3059 operations) was all index operations in 2002-2007, age 0-18 years with Primary Diagnosis of TOF, and Primary Procedure TOF repair or palliation. Patients with Pulmonary Atresia, Absent Pulmonary Valve, and Atrioventricular Canal were excluded.
294 patients had initial palliation, including 178 neonates. 2534 patients had repair of TOF as the initial operation (primary repair), including 154 neonates. 217 patients had repair of TOF after prior palliation. Of patients who had primary repair (n = 2534), 975 had repair at 3 to 6 months, 614 at 6 months to 1 year, 492 at 1 to 3 months, and 154 at 0 to 30 days. Of patients who had repair following prior palliation (n = 217), 65 had repair in the first 6 months of life, 111 at 6 months to 1 year, and only 41 (18.9%) at more than 1 year of age. Type of repair: Of 2534 primary repairs, 581 (23%) had no ventriculotomy, 571 (23%) had nontransanular patch, 1329 (52%) had transanular patch, and 53 (2%) had right ventricle to pulmonary artery conduits. Of repairs after prior palliation (n = 217), 20 (9%) had no ventriculotomy, 30 (14%) had nontransanular patch, 144 (66%) had transanular patch, and 24 (11%) had conduits. Discharge mortality (95% confidence interval; CI) was 22 of 294 (7.5%; CI: 4.7%-11.1%) for initial palliation, 33 of 2534 (1.3%; CI: 0.9%-1.8%) for primary repair, and 2 of 217 (0.9%; CI: 0.1%-3.3%) for secondary repair. For neonates, discharge mortality was 11 of 178 (6.2%; CI: 3.1%-10.8%) for palliation and 12 of 154 (7.8%; CI: 4.1%-13.2%) for primary repair.
Primary repair in the first year of life is the most prevalent strategy. Despite contemporary awareness of the late consequences of pulmonary insufficiency, ventriculotomy with transanular patch remains the most prevalent technique, both for primary repair and for repair following palliation.
Facioscapulohumeral muscular dystrophy (FSHD) is caused by an unusual deletion with neomorphic activity. This deletion derepresses genes in cis; however which candidate gene causes the FSHD ...phenotype, and through what mechanism, is unknown. We describe a novel genetic tool, inducible cassette exchange, enabling rapid generation of isogenetically modified cells with conditional and variable transgene expression. We compare the effects of expressing variable levels of each FSHD candidate gene on myoblasts. This screen identified only one gene with overt toxicity: DUX4 (double homeobox, chromosome 4), a protein with two homeodomains, each similar in sequence to Pax3 and Pax7. DUX4 expression recapitulates key features of the FSHD molecular phenotype, including repression of MyoD and its target genes, diminished myogenic differentiation, repression of glutathione redox pathway components, and sensitivity to oxidative stress. We further demonstrate competition between DUX4 and Pax3/Pax7: when either Pax3 or Pax7 is expressed at high levels, DUX4 is no longer toxic. We propose a hypothesis for FSHD in which DUX4 expression interferes with Pax7 in satellite cells, and inappropriately regulates Pax targets, including myogenic regulatory factors, during regeneration.
Crosstalk and insertion loss are the crucial determinants of ring resonated routers. A novel 2 × 2 optical switch is proposed through a combination of broadband waveguide crossing and X-shape ...photonic crystal ring resonators. The main goal of the proposed design is to demonstrate the switching wavelengths based on changing the refractive index and reduce the level of the crosstalk and insertion loss. The performance of the proposed structure is analyzed using two-dimensional finite difference time domain and plane-wave expansion methods. Results show that crosstalk noise and insertion loss can be significantly reduced by using optimized crossbar waveguide and novel structure with bending elimination, thereby allowing higher network scalability and better performance and utility for future many-core architectures. Maximum crosstalk and insertion loss of −37.41 and 0.3 dB are obtained at 1570.5 nm, respectively. The size of the proposed structure is 18.69 × 19.6 μm
2
, which can be used for photonic integrated circuits design due to its compactness.
The authors sought to assess the incidence, predictors, management, and prognosis of acute coronary syndrome (ACS) following TAVR.
About one-half of the patients undergoing transcatheter aortic valve ...replacement (TAVR) have concurrent coronary artery disease (CAD). However, the occurrence and clinical impact of coronary events following TAVR remain largely unknown.
Consecutive patients undergoing TAVR in our institution between May 2007 and November 2017 were included. Patients were followed at 1, 6, and 12 months, and yearly thereafter. ACS was diagnosed and classified according to the Third Universal Definition of Myocardial Infarction.
A total of 779 patients (mean age 79 ± 9 years, 52% male, mean STS: 6.8 ± 5.1%) were included, 68% of which had a history of CAD. At a median follow-up of 25 (interquartile range: 10 to 44) months, 78 patients (10%) presented at least 1 episode of ACS, with one-half of the events occurring within the year following TAVR. Clinical presentation was type 2 non–ST-segment elevation myocardial infarction (35.9%), unstable angina (34.6%), type 1 non–ST-segment elevation myocardial infarction (28.2%), and ST-segment elevation myocardial infarction (1.3%). Male sex (hazard ratio HR: 2.19; 95% confidence interval CI: 1.36 to 3.54; p = 0.001), prior CAD (HR: 2.78; 95% CI: 1.50 to 5.18; p = 0.001), and nontransfemoral approach (HR: 1.71; 95% CI: 1.04 to 2.75; p = 0.035) were independently associated with ACS. Coronary angiography was performed in 53 (67.9%) patients with ACS, and 30 of them (56.6%) underwent percutaneous coronary intervention. In-hospital death rate at the time of the ACS episode was 3.8%. At a median follow-up of 21 (interquartile range: 8 to 34) months post-ACS, all-cause and cardiovascular death rates were 37.3% and 25.3%, respectively.
Approximately one-tenth of patients undergoing TAVR were readmitted for an ACS after a median follow-up of 25 months. Male sex, prior CAD, and nontransfemoral approach were independent predictors of ACS. ACS was associated with high midterm mortality.
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