1,031 research outputs found

    An Efficient Decomposition Algorithm for Large-Scale Network Slicing

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    In this paper, we consider the network slicing (NS) problem which attempts to map multiple customized virtual network requests to a common shared network infrastructure and allocate network resources to meet diverse service requirements. We propose an efficient decomposition algorithm for solving this NP-hard problem. The proposed algorithm decomposes the large-scale hard NS problem into two relatively easy function placement (FP) and traffic routing (TR) subproblems and iteratively solves them enabling information feedback between each other, which makes it particularly suitable to solve large-scale problems. Specifically, the FP subproblem is to place service functions into cloud nodes in the network, and solving it can return a function placement strategy based on which the TR subproblem is defined; and the TR subproblem is to find paths connecting two nodes hosting two adjacent functions in the network, and solving it can either verify that the solution of the FP subproblem is an optimal solution of the original problem, or return a valid inequality to the FP subproblem that cuts off the current infeasible solution. The proposed algorithm is guaranteed to find the global solution of the NS problem. We demonstrate the effectiveness and efficiency of the proposed algorithm via numerical experiments.Comment: 5 pages, 4 figures, accepted for publication in IEEE SPAWC 202

    Data-based assessment of environmental controls on global marine nitrogen fixation

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    © The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Biogeosciences 11 (2014): 691-708, doi:10.5194/bg-11-691-2014.There are a number of hypotheses concerning the environmental controls on marine nitrogen fixation (NF). Most of these hypotheses have not been assessed against direct measurements on the global scale. In this study, we use ~ 500 depth-integrated field measurements of NF covering the Pacific and Atlantic oceans to test whether the spatial variance of these measurements can be explained by the commonly hypothesized environmental controls, including measurement-based surface solar radiation, mixed layer depth, average solar radiation in the mixed layer, sea surface temperature, wind speed, surface nitrate and phosphate concentrations, surface excess phosphate (P*) concentration and subsurface minimum dissolved oxygen (in upper 500 m), as well as model-based P* convergence and atmospheric dust deposition. By conducting simple linear regression and stepwise multiple linear regression (MLR) analyses, surface solar radiation (or sea surface temperature) and subsurface minimum dissolved oxygen are identified as the predictors that explain the most spatial variance in the observed NF data, although it is unclear why the observed NF decreases when the level of subsurface minimum dissolved oxygen is higher than ~ 150 μM. Dust deposition and wind speed do not appear to influence the spatial patterns of NF on global scale. The weak correlation between the observed NF and the P* convergence and concentrations suggests that the available data currently remain insufficient to fully support the hypothesis that spatial variability in denitrification is the principal control on spatial variability in marine NF. By applying the MLR-derived equation, we estimate the global-integrated NF at 74 (error range 51–110) Tg N yr−1 in the open ocean, acknowledging that it could be substantially higher as the 15N2-assimilation method used by most of the field samples underestimates NF. More field NF samples in the Pacific and Indian oceans, particularly in the oxygen minimum zones, are needed to reduce uncertainties in our conclusion.This project was supported by the NSF Center for Microbial Oceanography: Research and Education (C-MORE) (EF-0424599), an NSF Emerging Topics in Biogeochemical Cycles grant (ETBC, AGS-1020594), and the Gordon and Betty Moore Foundation

    Application of HCRM in process reengineering and quality control of Obstetrics and Gynecology

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    目的  借鉴医院客户关系管理(HCRM)的理念,从流程管理入手,探讨运用质量管理工具,建立 “以患者为中心”的管理体系,持续改进服务质量的有效途径。方法  把“以患者为中心”的服务理念贯彻到各个流程环节,通过与患者的交流沟通,了解患者的需求[1],患者对医院的态度,运用PDCA循环对现有的业务流程、服务流程和管理流程进行分析与论证,以患者的需求为导向,以质量为核心,进行流程改造,遵循规范-创新-再规范-再创新的护理管理思维,实现科学的质量管理。结果  HCRM对流程再造的影响呈现在多个方面,流程再造实施后,护理安全事件发生率、患者对新老门诊护理服务满意度4项指标、护士体验及满意度、评价显著优于实施前(均P < 0.01),护理质量6项对比差异有显著意义(P < 0.05)。结论  将HCRM的理念运用到流程再造中,有利于提高护理质量和护理安全,同时提升了护理人员综合素质,从而提高患者对护理服务的满意度。Objective: Using the hospital customer relationship management (HCRM) concept for reference, starting from the process management, explore using quality management tools to establish the management system of " the patient as the center " and the effective way to improve service quality. Methods:Take the concept of “the patient as the center" to various processes, through the communication with patients, to understand the needs of patients, patients’ attitudes to the hospital, apply the PDCA cycle to analyze and demonstrate the existing business process, service process and management process . With the patient's demand as the guidance, take the quality as the core, reengineer the process , and follow the nursing management thinking of specification - innovation - Specification - a further innovation to achieve the quality of management science. Results: The effects of HCRM on process reengineering present in many aspects ,after the process reengineering, nursing safety event rate, with new and old outpatient nursing service satisfaction of 4 indexes, the nurse experience and satisfaction, evaluation is significantly better than before the implementation( all P < 0.01) There are significant differences between the quality of nursing 5indexes (P < 0.05). Conclusion: The HCRM concept to the process reengineering is helpful to improve the nursing care quality and safety, at the same time, improve the comprehensive quality of nursing staff, so as to improve the patients' satisfaction to nursing service

    Important photosynthetic contribution from the non-foliar green organs in cotton at the late growth stage

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    Non-foliar green organs are recognized as important carbon sources after leaves. However, the contribution of each organ to total yield has not been comprehensively studied in relation to the time-course of changes in surface area and photosynthetic activity of different organs at different growth stages. We studied the contribution of leaves, main stem, bracts and capsule walls in cotton by measuring their time-course of surface area development, O2 evolution capacity and photosynthetic enzyme activity. Because of the early senescence of leaves, non-foliar organs increased their surface area up to 38.2% of total at late growth stage. Bracts and capsule wall showed less ontogenetic decrease in O2 evolution capacity per area and photosynthetic enzyme activity than leaves at the late growth stage. The total capacity for O2 evolution of stalks and bolls (bracts plus capsule wall) was 12.7% and 23.7% (total ca. 36.4%), respectively, as estimated by m! ultiplying their surface area by their O2 evolution capacity per area. We also kept the bolls (from 15 days after anthesis) or main stem (at the early full bolling stage) in darkness for comparison with non-darkened controls. Darkening the bolls and main stem reduced the boll weight by 24.1% and 9%, respectively, and the seed weight by 35.9% and 16.3%, respectively. We conclude that non-foliar organs significantly contribute to the yield at the late growth stage

    Metformin plus megestrol acetate compared with megestrol acetate alone as fertility‐sparing treatment in patients with atypical endometrial hyperplasia and well‐differentiated endometrial cancer: a randomised controlled trial

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    Objective: To assess the efficacy of metformin in megestrol acetate (MA)-based fertility-sparing treatment for patients with atypical endometrial hyperplasia (AEH) and endometrioid endometrial cancer (EEC). Design: A randomised, single-centre, open-label, controlled trial conducted between October 2013 and December 2017. Setting: Shanghai OBGYN Hospital of Fudan University, China. Population: A total of 150 patients (18-45 years old) with primary AEH or well-differentiated EEC were randomised into an MA group (n = 74) and an MA plus metformin group (n = 76). Methods: Patients with AEH or EEC were firstly stratified, then randomised to receive MA (160 mg orally, daily) or MA (160 mg orally, daily) plus metformin (500 mg orally, three times a day). Main outcomes and measures: The primary efficacy parameter was the cumulate complete response (CR) rate within 16 weeks of treatment (16w-CR rate); the secondary efficacy parameters were 30w-CR rate and adverse events. Results: The 16w-CR rate was higher in the metformin plus MA group than in the MA-only group (34.3 versus 20.7%, odds ratio [OR] 2.0, 95% confidence interval [CI] 0.89-4.51, P = 0.09) but the difference was more significant in 102 AEH patients (39.6 versus 20.4%, OR 2.56, 95% CI 1.06-6.21, P = 0.04). This effect of metformin was also significant in non-obese (51.4 versus 24.3%, OR 3.28, 95% CI 1.22-8.84, P = 0.02) and insulin-sensitive (54.8 versus 28.6%, OR 3.04, 95% CI 1.03-8.97, P = 0.04) subgroups of AEH women. No significant result was found in secondary endpoints. Conclusion: As a fertility-sparing treatment, metformin plus MA was associated with a higher early CR rate compared with MA alone in AEH patients. Tweetable abstract For AEH patients, metformin plus MA might be a better fertility-sparing treatment to achieve a higher early CR rate compared with MA alone
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