536 research outputs found

    TimeTrader: Exploiting Latency Tail to Save Datacenter Energy for On-line Data-Intensive Applications

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    Datacenters running on-line, data-intensive applications (OLDIs) consume significant amounts of energy. However, reducing their energy is challenging due to their tight response time requirements. A key aspect of OLDIs is that each user query goes to all or many of the nodes in the cluster, so that the overall time budget is dictated by the tail of the replies' latency distribution; replies see latency variations both in the network and compute. Previous work proposes to achieve load-proportional energy by slowing down the computation at lower datacenter loads based directly on response times (i.e., at lower loads, the proposal exploits the average slack in the time budget provisioned for the peak load). In contrast, we propose TimeTrader to reduce energy by exploiting the latency slack in the sub- critical replies which arrive before the deadline (e.g., 80% of replies are 3-4x faster than the tail). This slack is present at all loads and subsumes the previous work's load-related slack. While the previous work shifts the leaves' response time distribution to consume the slack at lower loads, TimeTrader reshapes the distribution at all loads by slowing down individual sub-critical nodes without increasing missed deadlines. TimeTrader exploits slack in both the network and compute budgets. Further, TimeTrader leverages Earliest Deadline First scheduling to largely decouple critical requests from the queuing delays of sub- critical requests which can then be slowed down without hurting critical requests. A combination of real-system measurements and at-scale simulations shows that without adding to missed deadlines, TimeTrader saves 15-19% and 41-49% energy at 90% and 30% loading, respectively, in a datacenter with 512 nodes, whereas previous work saves 0% and 31-37%.Comment: 13 page

    Confronting the opioid crisis: Practical pain management and strategies: AOA 2018 critical issues symposium

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    The United States is in the midst of an opioid crisis. Clinicians have been part of the problem because of overprescribing of narcotics for perioperative pain management. Clinicians need to understand the pathophysiology and science of addiction to improve perioperative management of pain for their patients. Multiple modalities for pain management exist that decrease the use of narcotics. Physical strategies, cognitive strategies, and multimodal medication can all provide improved pain relief and decrease the use of narcotics. National medical societies are developing clinical practice guidelines for pain management that incorporate multimodal strategies and multimodal medication. Changes to policy that improve provider education, access to naloxone, and treatment for addiction can decrease narcotic misuse and the risk of addiction

    A Study on Female Entrepreneurs in Malaysia

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    This paper summarizes the impact of challenges within the scientific discussion on the issue of female entrepreneurship in Malaysia. In 67 countries of the world, approximately 126 millions of women have started a new business, and 98 millions of women are developing the already established businesses starting from 2012. However, the proportion of female entrepreneurs in general ranges from 1% to 40% in different countries around the world depending on the economic development, so the impact of women entrepreneurship on innovation and job creation is especially significant for developing countries, in particular for Malaysia

    HIV-exposed uninfected infants show robust memory B cell responses in spite of a delayed accumulation of memory B cells: An observational study in the first two years of life.

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    Background Improved HIV care has led to an increase in the number of HIV-exposed uninfected (HEU) infants born to HIV infected women. Although uninfected, these infants experience increased morbidity and mortality. One explanation may be that their developing immune system is altered by HIV-exposure predisposing them to increased post-natal infections. Methods We explored the impact of HIV-exposure on the B-cell compartment by determining the B-cell subset distribution, the frequency of common vaccine antigen-specific memory B cells (MBCs) and their respective antibody levels in HEU and HIV-unexposed uninfected (HUU) infants born to uninfected mothers, using flow cytometry, B-cell ELISPOT and ELISA, respectively, during the first two years of life. Results For the majority of the B-cell subsets there were no differences between HEU and HUU infants. However, HIV exposure was associated with a lower proportion of B cells in general and specifically MBCs, largely due to a lower proportion of unswitched memory B cells. This reduction was maintained even after correcting for age. These phenotypic differences in the MBC compartment did not affect the ability of HEU infants to generate recall responses to previously encountered antigens, or reduce the antigen-specific antibody levels at 18 months of life. Conclusions Although HIV-exposure was associated with a transient reduction in the proportion of MBCs, we found that the ability of HEUs to mount robust MBC and serological responses was unaffected

    Optimal Compressive Strength of RHA Ultra-High-Performance Lightweight Concrete (UHPLC) and Its Environmental Performance Using Life Cycle Assessment

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    Frequent laboratory needs during the production of concrete for infrastructure development purposes are a factor of serious concern for sustainable development. In order to overcome this trend, an intelligent forecast of the concrete properties based on multiple data points collected from various concrete mixes produced and cured under different conditions is adopted. It is equally important to consider the impact of the concrete components in this attempt to take care of the environmental risks involved in this production. In this work, 192 mixes of an ultra-high-performance lightweight concrete (UHPLC) were collected from literature representing different mixes cured under different periods and laboratory conditions. These mix proportions constitute measured variables, which are curing age (A), cement content (C), fine aggregate (FAg), plasticizer (PL), and rice husk ash (RHA). The studied concrete property was the unconfined compressive strength (Fc). This exercise was necessary to reduce multiple dependence on laboratory examinations by proposing concrete strength equations. First, the life cycle assessment evaluation was conducted on the rice husk ash-based UHPLC, and the results from the 192 mixes show that the C-783 mix (87 kg/m3 RHA) has the highest score on the environmental performance evaluation, while C-300 (75 kg/m3 RHA) with life cycle indices of 289.85 kg CO2eq. Global warming potential (GWP), 0.66 kg SO2eq. Terrestrial acidification and 5.77 m3 water consumption was selected to be the optimal choice due to its good profile in the LCA and the Fc associated with the mix. Second, intelligent predictions were conducted by using six algorithms (ANN-BP), (ANN-GRG), (ANN-GA), (GP), (EPR), and (GMDH-Combi). The results show that (ANN-BP) with performance indices of R; 0.989, R2; 0.979, mean square error (MSE); 2252.55, root mean squared error (RMSE); 42.46 MPa and mean absolute percentage error (MAPE); 4.95% outclassed the other five techniques and is selected as the decisive model. However, it also compared well and outclassed previous models, which had used gene expression programming (GEP) and random forest regression (RFR) and achieved R2of 0.96 and 0.91, respectively. Doi: 10.28991/CEJ-2022-08-11-03 Full Text: PD

    A Grid-Connected Optimal Hybrid PV-BES System Sizing for Malaysian Commercial Buildings

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    In this article, the optimal sizing of hybrid solar photovoltaic and battery energy storage systems is evaluated with respect to rooftop space and feed-in tariff rates. The battery scheduling is performed using a proposed rule-based energy management strategy. The rules are formulated based on the demand limit, PV export power limit, and state of charge of the battery. Furthermore, optimization modeling with initial choices of parameters and constraints in terms of solar photovoltaic and battery energy storage capabilities is developed to minimize the total net present cost. The hourly values of solar irradiance, air temperature, electrical loads, and electricity rates are considered the inputs of the optimization process. The optimization results are achieved using particle swarm optimization and validated through an uncertainty analysis. It is observed that an optimal photovoltaic and battery energy storage system can reduce the cost of electricity by 12.33%,including the sale of 5944.029 kWh of electricity to the grid. Furthermore, energy consumption, peak demand, and greenhouse gas emissions are reduced by 13.71%, 5.85%, and 62.59%, respectively. A comprehensive analysis between the variable and fixed data for the load, energy from PV, batteries, and the grid, and costs demonstrates that the optimal sizing of photovoltaic and battery energy storage systems with the best mix of energy from PV, batteries, and the grid provides the optimal solution for the proposed configuration

    Paclitaxel and Sorafenib: The Effective Combination of Suppressing the Self-Renewal of Cancer Stem Cells

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    Combination therapy, which is a treatment modality combining two or more therapeutic agents, is considered a cornerstone of cancer therapy. The combination of anticancer drugs, of which functions are different from the other, enhances the efficiency compared to the monotherapy because it targets cancer cells in a synergistic or an additive manner. In this study, the combination of paclitaxel and sorafenib in low concentration was evaluated to target cancer stem cells, miPS-BT549cmP and miPS-Huh7cmP cells, developed from mouse induced pluripotent stem cells. The synergistic effect of paclitaxel and sorafenib on cancer stem cells was assessed by the inhibition of proliferation, self-renewal, colony formation, and differentiation. While the IC(50)values of paclitaxel and sorafenib were approximately ranging between 250 and 300 nM and between 6.5 and 8 mu M, respectively, IC(50)of paclitaxel reduced to 20 and 25 nM, which was not toxic in a single dose, in the presence of 1 mu M sorafenib, which was not toxic to the cells. Then, the synergistic effect was further assessed for the potential of self-renewal of cancer stem cells by sphere formation ability. As a result, 1 mu M of sorafenib significantly enhanced the effect of paclitaxel to suppress the number of spheres. Simultaneously, paclitaxel ranging in 1 to 4 nM significantly suppressed not only the colony formation but also the tube formation of the cancer stem cells in the presence of 1 mu M sorafenib. These results suggest the combination therapy of paclitaxel and sorafenib in low doses should be an attractive approach to target cancer stem cells with fewer side effects

    Editorial: Influence of environmental variability on climate change impacts in marine ecosystems

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    multiple drivers, environmental variability, Climate change, marine heatwaves, stressmemory, Ecological memory, Thermal performance curves, acclimatio
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