This paper proposes a distributed model predictive control scheme for the load frequency control (LFC) problem of the deregulated multi-area interconnected power system with contracted and ...uncontracted load demands. The traditional LFC of the interconnected power system is modified to take into account the effect of bilateral contracts on the dynamics. The concept of the distribution company participation matrix and area participation matrix are introduced to simulate these bilateral contracts and reflected in the multi-area block diagram. The distributed model predictive controller is designed by posing the LFC problem as a tracking control problem in the presence of both external disturbances and constraints that represent generation rate constraint and load reference setpoint constraint, respectively. Analysis and simulation results for a deregulated three-area interconnected power system show possible improvements on closed-loop performance and computational burden, while respecting the physical hard constraints.
The China's economy is developing rapidly, and it affects the environment on several levels. Therefore, this study examines the effect of environmental management accounting, green human resource ...management (HRM), on green organisational behaviour (OB). We collected 383 questionnaires completed by human resource managers and accounting managers in the Chinese hospitality industry. We used a covariance-based structural equation model to test the hypotheses in this study. The empirical evidence shows a positive and significant effect between environmental management accounting (monetary environmental management accounting, and physical environmental management accounting) and green HRM (β = 0.262, p < 0.01, β = 0.378, p< 0.01). Green HRM mediates the influence of environmental management accounting (monetary environmental management accounting, β = 0.059, p < 0.01; physical environmental management accounting, β = 0.084, p< 0.01) on green OB. The analysis confirmed the importance of environmental management accounting (as opposed to green human resource management) in predicting green behaviour and the critical role of green human resource management in connecting environmental management accounting and green OB. Thus, this study extends the literature's perspective on green OB to environmental management accounting and green HRM.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
We aimed to report the clinical characteristics of imported cases of coronavirus disease 2019 (COVID-19) in Jiangsu Province.
Methods
We retrospectively investigated the clinical, ...imaging, and laboratory characteristics of confirmed cases of COVID-19 with World Health Organization interim guidance in 3 grade IIIA hospitals of Jiangsu from 22 January to 14 February 2020. Real-time RT-PCR was used to detect the new coronavirus in respiratory samples.
Results
Of the 80 patients infected with COVID-19, 41 were female, with a median age of 46.1 years. Except for 3 severe patients, the rest of the 77 patients exhibited mild or moderate symptoms. Nine patients were unconfirmed until a third nucleic acid test; 38 cases had a history of chronic diseases. The main clinical manifestations of the patients were fever and cough, which accounted for 63 (78.75%) and 51 (63.75%) cases, respectively. Only 3 patients (3.75%) showed liver dysfunction. Imaging examination showed that 55 patients (68.75%) showed abnormal density shadow and 25 cases (31.25%) had no abnormal density shadow in the parenchyma of both lungs. Currently, 21 cases have been discharged from the hospital, and no patient died. The average length of stay for discharged patients was 8 days.
Conclusions
Compared with the cases in Wuhan, the cases in Jiangsu exhibited mild or moderate symptoms and no obvious gender susceptibility. The proportion of patients having liver dysfunction and abnormal CT imaging was relatively lower than that in Wuhan. Notably, infected patients may be falsely excluded based on 2 consecutively negative respiratory pathogenic nucleic acid test results.
Compared with the cases in Wuhan, 80 imported cases of COVID-19 in Jiangsu Province exhibited mild or moderate symptoms and no obvious gender susceptibility, lower proportion of liver dysfunction, and abnormal CT imaging and higher frequency of nucleic acid detection.
Salary is perceived as a key factor affecting job satisfaction, employment, and the retention or migration of physicians within and across countries. This study aimed to describe physicians' salary ...and workload and to examine the factors determining the salary of physicians in China.
We conducted a self-administered, smartphone-based national survey in 136 tertiary hospitals across 31 provinces. A total of 17,615 physicians self-reported their salaries after tax and their characteristics, practice settings, and work efforts in 2015. Then, 2498 of the physicians were followed up for the second-round survey in 2016. Univariate analysis and general estimate equations were applied to evaluate the factors associated with salary.
In 2015, the average annual salary of the physicians was US$13,764. Physicians in eastern China earned more than those in central (p < 0.001) and western China (p = 0.002) after adjustment for locality expenditure per capita. The salary for men in 2015 was US$14,832, which was more than that for women (US$12,912; p < 0.001). Of the respondents, 76.3% worked more than 40 h per week. The physicians dealt with 40 patients per day on average. Consequently, 67.2% physicians spent no more than 10 min with each outpatient. After adjustments for age and management position, salary was associated with years in practice, education background, and specialty, but not with weekly work hours and gender.
The physicians' salaries were relatively low, and the majority of the respondents worked more than 40 h per week. Years in practice, education background, specialty, and region were associated with salary, while weekly work hours and gender were not. To better remunerate Chinese physicians, more resources are demanded, and a workload-based salary scheme should be adopted.
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CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Renewable energy sources such as wind and solar have received much attention in recent years, and large amounts of renewable generation are being integrated into electricity networks. A fundamental ...challenge in power system operation is to handle the intermittent nature of renewable generation. In this paper, we present a stochastic programming approach to solve a multiperiod optimal power flow problem under renewable generation uncertainty. The proposed approach consists of two stages. In the first stage, operating points of the conventional power plants are determined. The second stage realizes generation from the renewable resources and optimally accommodates it by relying on the demand-side flexibilities. The proposed model is illustrated on a 4-bus and a 39-bus system. Numerical results show that substantial benefits in terms of redispatch costs can be achieved with the help of demand side flexibilities. The proposed approach is tested on the standard IEEE test networks of up to 300 buses and for a wide variety of scenarios for renewable generation.
•This paper reviews typical RTMs in the North America, Australia and Europe.•The successful RTM experiences are summarized and discussed in three groups.•Technical overview of the RTMs integrating ...DER and DR is presented.
The high penetration of both Distributed Energy Resources (DER) and Demand Response (DR) in modern power systems requires a sequence of advanced strategies and technologies for maintaining system reliability and flexibility. Real-time electricity markets (RTM) are the non-discriminatory transaction platforms for providing necessary balancing services, where the market clearing (nodal or zonal prices depending on markets) is very close to real time operations of power systems. One of the primary functions of RTMs in modern power systems is establishing an efficient and effective mechanism for small DER and DR to participate in balancing market transactions, while handling their meteorological or intermittent characteristics, facilitating asset utilization, and stimulating their active responses. Consequently, RTMs are dedicated to maintaining the flexibility and reliability of power systems. This paper reviews advanced typical RTMs respectively in the North America, Australia and Europe, focusing on their market architectures and incentive policies for integrating DER and DR in electricity markets. In this paper, RTMs are classified into three groups: Group I applies nodal prices implemented by optimal power flow, which clears energy prices every 5min. Group II applies zonal prices, with the time resolution of 5-min. Group III is a general balancing market, which clears zonal prices intro-hourly. The various successful advanced RTM experiences have been summarized and discussed, which provides a technical overview of the present RTMs integrating DER and DR.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The membrane fouling is the obstruction that limits the efficiency and durability of the nanofibrous membrane in oil-water emulsion separation. Herein, a polyvinyl alcohol (PVA) hydrogel nanofibrous ...membrane could continuously separate emulsion by using squeezing coalescence demulsification (SCD). During this SCD process, the small oil droplets can coalesce into bigger ones under the mandatory compression of the pore wall. And then the coalesced oil droplets will pass through the nanofibrous membrane and form an oil layer, and the oil layer can be easily removed. Furthermore, a two-phase numerical model is proposed to demonstrate this coalescence process of oil droplets in the pore. The numerical results also indicate that the pore size, wettability of membrane, and the interface tension coefficient between oil and water can control the efficiency of SCD. This SCD method endows PVA hydrogel nanofibrous membrane with a sustained separation capability, which implys that this method has great potential in practical application.
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•Squeezing coalescence demulsification can constantly split oil/water emulsion.•Squeezing coalescence demulsification can overcome nanofibrous membrane fouling.•A numerical model can predict the results of squeezing coalescence demulsification.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Statement of problem Recently a new therapeutic concept of patient-specific implant dentistry has been advanced based on computer-aided design/computer-aided manufacturing technology. However, a ...comprehensive study of the design and 3-dimensional (3D) printing of the customized implants, their mechanical properties, and their biomechanical behavior is lacking. Purpose The purpose of this study was to evaluate the mechanical and biomechanical performance of a novel custom-made dental implant fabricated by the selective laser melting technique with simulation and in vitro experimental studies. Material and methods Two types of customized implants were designed by using reverse engineering: a root-analog implant and a root-analog threaded implant. The titanium implants were printed layer by layer with the selective laser melting technique. The relative density, surface roughness, tensile properties, bend strength, and dimensional accuracy of the specimens were evaluated. Nonlinear and linear finite element analysis and experimental studies were used to investigate the stress distribution, micromotion, and primary stability of the implants. Results Selective laser melting 3D printing technology was able to reproduce the customized implant designs and produce high density and strength and adequate dimensional accuracy. Better stress distribution and lower maximum micromotions were observed for the root-analog threaded implant model than for the root-analog implant model. In the experimental tests, the implant stability quotient and pull-out strength of the 2 types of implants indicated that better primary stability can be obtained with a root-analog threaded implant design. Conclusions Selective laser melting proved to be an efficient means of printing fully dense customized implants with high strength and sufficient dimensional accuracy. Adding the threaded characteristic to the customized root-analog threaded implant design maintained the approximate geometry of the natural root and exhibited better stress distribution and primary stability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Gold (Au) nanoclusters with diameters less than 2 nm are attracting increasing attention due to their unique size-dependent physicochemical properties which include strong luminescence and excellent ...biocompatibility. Accordingly, Au nanoclusters are now becoming essential in biomedical research for bioimaging, biosensing, quantitative analysis of protein and ion detection. In this mini review, the luminescence mechanism and biosynthesis of Au nanoclusters is systematically explored, followed by a brief survey of Au nanoclusters applications across the biomedical sector. Particular emphasis is placed on the role of biological molecules such as proteins, peptides and low molecular weight organic compounds in the synthesis of small luminescent Au nanoclusters, either as templates or surface capping agents. Successful strategies for applying luminescent Au nanoclusters in bioimaging and biosensing are also summarized. Future areas for Au nanocluster utilization in biomedical research are briefly discussed.
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•In this mini review, the luminescence mechanism and biosynthesis of Au nanoclusters is systematically explored.•Particular emphasis is placed on the role of biological molecules in the synthesis of small luminescent Au nanoclusters.•Successful strategies for applying luminescent Au nanoclusters in bioimaging and biosensing are also summarized.•Future areas for Au nanocluster utilization in biomedical research are briefly discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background:
Glycosyltransferase participates in glycosylation modification, and glycosyltransferase alterations are involved in carcinogenesis, progression, and immune evasion, leading to poor ...outcomes. However, in-depth studies on the influence of glycosyltransferase on clinical outcomes and treatments are lacking.
Methods:
The analysis of differentially expressed genes was performed using the Gene Expression Profiling Interactive Analysis 2 database. A total of 10 machine learning algorithms were introduced, namely, random survival forest, elastic network, least absolute shrinkage and selection operator, Ridge, stepwise Cox, CoxBoost, partial least squares regression for Cox, supervised principal components, generalized boosted regression modeling, and survival support vector machine. Gene Set Enrichment Analysis was performed to explore signaling pathways regulated by the signature. Cell-type identification by estimating relative subsets of RNA transcripts was used for estimating the fractions of immune cell types.
Results:
Here, we analyzed the genomic and expressive alterations in glycosyltransferase-related genes in gliomas. A combination of 80 machine learning algorithms was introduced to establish the glycosyltransferase-related mRNA signature (GRMS) based on 2,030 glioma samples from The Cancer Genome Atlas Program, Chinese Glioma Genome Atlas, Rembrandt, Gravendeel, and Kamoun cohorts. The GRMS was identified as an independent hazardous factor for overall survival and exhibited stable and robust performance. Notably, gliomas in the high-GRMS subgroup exhibited abundant tumor-infiltrating lymphocytes and tumor mutation burden values, increased expressive levels of hepatitis A virus cellular receptor 2 and CD274, and improved progression-free survival when subjected to anti-tumor immunotherapy.
Conclusion:
The GRMS may act as a powerful and promising biomarker for improving the clinical prognosis of glioma patients.
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