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This paper proposes a novel approach for providing long-run marginal cost (LRMC) pricing in network charges. The proposed approach makes use of the unused capacity of an exiting network to reflect the cost of advancing or deferring future investment consequent upon the perturbation of generation or load at each study node on a distribution or transmission network. Compared with existing approaches to LRMC pricing, the proposed approach produces forward-looking charges that reflect both the extent of the network needed to service the generation and/or load, and the degree to which that network is utilized. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells(MSCs) transplantation to overcome deficient β-cell population is an attractive proposal. Nevertheless, the efficiency of adult stem cells to differentiate into islet-like cells in vitro is low at present. Stem cell differentiation is controlled by extra-cellular cues from the environment and by intrinsic genetic programs within the stem cell. The present study aimed to explore whether diabetic microenvironment could induce MSCs to trans-differentiate to islet cells and compensate insufficient β-cell. We transplanted male EGFP transduct MSCs to experimental diabetic female pig by multipoint injecting into subcapsular pancreas. MSCs not only act as "seed" cells, but also may exert a clinically useful immune modulatory effect, because of their immune privilege. Four weeks later, glucose level in serum began to decrease gradually, and was approximate to normal value. Reversal of diabetes was evidenced by normal insulin level in serum and normal intra-peritoneal glucose tolerance test. Pancreatic neo-genesis islets were verified by histology and morphometry. EGFP and insulin protein coexpression indicated that some of neo-genesis islet cells derived from transplanted MSCs and had normal function. Co-expression of Y-chromosome SRY gene and insulin mRNA, Pdx-1 mRNA, future clarified the results. This study shows that bone marrow derived MSCs could contribute functional islets in diabetic pancreatic microenvironment and no obvious immune rejections, which provide a theoretical and clinical applications of pancreas regeneration. [ABSTRACT FROM AUTHOR]

Microarray technology is becoming one of the most productive methods used to elucidate the complex interdependence present in biological systems. This technology can be used to compare nature cells with cells differentiated from stem cells to identify molecular differences between them. To date, only a few reports have analyzed differentiated cells by microarray. Here, microarray was used to identify genes abnormally expressed in differentiated islet-like clusters compared with normal pancreas islet. Successful conversion of pancreatic stem cells (PSCs) into islet-like clusters has been reported. In this study, we investigated the properties of clusters by DTZ staining and microarray. DTZ stained clusters were selected out, then mRNA expression was investigated using microarray. In microarray there were 5 031 gene data of which the hybridization fluoresce signals from both pancreatic islet and the differentiated cells accorded with the effective signal standard. Compared with pancreatic islet, there were 1 772 genes with significantly different expression in differentiated cells, of which 797 increased and 975 decreased in expression. There were 3 052 gene data of which the hybridization fluoresce signals from only one kind of samples accorded with the effective signal standard. Compared with pancreatic islet, there were 1 771 genes with significantly different expression in differentiated cells, of which 678 increased and 1093 decreased in expression. In the view of gene expression mode, that 44% (3 543/8 083) effectively detected genes exist difference in expression reflects huge disparities in biological characteristic between 2 kinds of samples. Microarray analyses indicate that genes with obvious different expression relate to transcriptional control, regulation of cell growth, metabolism, adhesion, proliferation and so on. Loss/reduced levels of transcripts associated with pancreatic-specific lineage in differentiated cells suggest that differentiation from PSCs toward functional pancreatic islet in vitro is not efficient. [ABSTRACT FROM AUTHOR]

We modified previously described method for the generation of nestin-positive cells from adult mouse islets, further to research the characteristic of nestin- positive cells and explore the effect of basic fibroblast growth factor for nestin-positive cells. Nestin- positive cells could be isolate with high purity by using fluorescent-activated cell sorting and generate neural and islet cells .A subset of Pdx-1-positive cells in nestin- positive cells were demonstrated to differentiate into islet cells. Insulin, Glucagons, Somatostatin, Pdx-1, β3-tubulin, GFAP, nestin, Ngn-1, Ngn-2, Ngn3, Mash-1, Sox-1, Sox-2 and Sox-3 mRNA was detected by real time PCR at different stages during development of nestin- positive cells. Our results suggested that nestin expression might indicate the beginning of differentiation toward neural and islet cells. The similarity in gene expression program might exist in pancreatic and neural precursor cells. Although the absence of bFGF increased the percentage of insulin- positive cells and intracellular insulin level in nestin- positive-derived cells, insulin release in response to glucose was down-regulated compared with the presence of bFGF. bFGF was demonstrated to be an indispensable requirement for nestin-positive cells differentiate into functional insulin-producing cells. A reversibly immortalized nestin- positive cell line was established with adeno-X Tet-On vectors coding with SV40 virus large T-antigen. Establishment of a reversibly immortalized nestin-positive cells line would be a means for further investigating the mechanisms of islet cell development, and they could also provide a potential source of cells for islet engineering. [ABSTRACT FROM AUTHOR]

A novel route for copper-catalyzed tandem C--H/N--H activation, cyclization[4+2] and dehydration of arylamides with formamide to synthesize 4(3H)-quinazolinone derivatives was developed. This approach is assisted by an 8-aminoquinoline group and the formamide provide the nitrogen and carbon source. This reaction is compatible with various functional groups, and the reaction conditions are mild. In addition, it uses cheaply and commercially available reagents, and provides direct access to 4(3H)-quinazolinones. [ABSTRACT FROM AUTHOR]

Microgrids may suffer from full blackouts when confronted with unexpected disruptions due to man-made faults or natural disasters. How to quickly restore the power supply of microgrids by making use of local distributed energy resources (DERs) is therefore a practical issue to help microgrids ride through full blackouts. Accordingly, this study proposes a novel black start strategy for microgrids to determine the restoration sequence and optimally allocate the DERs after full blackouts. In particular, the uncertainty of power output of renewable energy sources is considered using a data-driven chance-constrained approach when renewable energy sources are integrated. The proposed approach only utilises historical data and does not need any prior knowledge about the true probability distribution of the uncertainty. In addition, affine-based techniques and sample-dependent band functions are developed to convert the chance-constrained problem into a tractable mixed-integer linear programming problem. Finally, numerical experiments based on two microgrid test systems are performed to validate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

Conventional distribution network is a radial network with a single power source. Usually, overcurrent protection schemes are employed for such system protection for their simplicity and low cost. With the introduction of renewable generations, the existing protection coordination needs to be upgraded. Provision of directional feature and the requirement of high capacity circuit-breakers at certain points for the protection scheme demands considerable investment. The renovation cost required for upgrading the protection scheme will significantly impact the network cost requirement and consequently distribution use of system (DUoS) charges. This study aims to investigate the impact of renewable generations on the DUoS charges considering the cost associated in revamping the protection scheme. A power flow based MW + MVAr-miles DUoS charging method, that considers used capacity of the network, is proposed to carry out the DUoS charging calculations. The proposed charging mechanism appraise/penalise the users in accordance they are affecting system power factor. Accordingly, the proposed pricing algorithm may encourage users to act based on the economic signal generated at each location. The proposed charging algorithm has been tested on IEEE-33 and IEEE-69 bus distribution systems to examine the impact of renewable generations on the use of network costs. [ABSTRACT FROM AUTHOR]

The existing transmission charging methods like long-run incremental cost give forward-looking charges which reflect the impact of system congestion on required network investment, but the flexibility of demand is not considered. This study proposes a novel transmission charging method which takes into consideration the demand response (DR). The proposed method could reflect: (1) how DR influences the short-run congestion management cost and long-run investment cost; (2) how DR influences the transmission charges. To promote the effect of DR, an approach is proposed to determine the optimal nodes for the implementation of DR based on the available transfer capability and congestion cost. Through the approach, different plans for the implementation of DR will be produced in different demand levels. The optimal node determination approach not only makes DR more targeted for the system congestion but also improves the effect of the proposed transmission charging method. The proposed method is applied to the IEEE 14-bus system and a practical system in Western China. The results indicate that the proposed charging method can offer consumers with economic incentives to alleviate congestion, especially when the DR implemented on the optimal nodes, and thus delay the network reinforcement investment. [ABSTRACT FROM AUTHOR]

The integration of demand flexibility in distributed generation (DG) planning either lacks accuracy or ignores the potential of the behaviour of consumers in promoting the integration of renewables. This study proposes a DG planning model coordinating demand flexibility, in which the DG expansion plan and the behaviour of consumers in demand response (DR) programmes are co-optimised for the highest social welfare and the optimal utilisation of renewable generation. Consequently, the supply cost is reduced by utilising higher renewable generation instead of buying electricity from the grid. A share of the cost savings is allocated to the consumers to encourage their participation in DR programmes. Simulation results show that the expansion capacity of renewable generation is increased by 7.4% compared with no demand flexibility incorporation, and the social welfare is increased by up to 13.5% compared with no DG installation and 3.1% compared with no demand flexibility incorporation. Besides, the DR programmes carried out in the distribution system interact with the DG expansion plan, and higher subsidy rates in DR programmes could further promote the integration of renewables. [ABSTRACT FROM AUTHOR]

In order to manage the charging behaviour of electric vehicles (EVs), this study for the first time develops a set of EV charging load profiles: EV templates. EV charging profiles have unique waveforms similar to a rectangular pulse train. This characteristics significantly limits the performance of clustering analysis in that traditional distance calculation, such as Euclidean distance, which cannot reflect the morphological dissimilarities. This study proposes a novel clustering method using rough set theory to accurately measure the dissimilarity between the EV profiles. The pulse train waves are firstly extracted as mixed data features, which are partitioned by an improved K-prototypes method based on rough set distance. The proposed method is implemented on the real charging load profiles and compared with K-means and traditional K-prototypes. Their clustering performances are evaluated by diverse validity indices. The results show that the proposed method outperforms other comparison methods. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the epidemiologic characteristics of avian influenza A(H7N9) cases in China identified as of December 1, 2013. Topics discussed include the verification of a case of H7N9 virus by means of real-time reverse-transcriptase-polymerase-chain-reaction assay (RT-PCR), the death of patients after a median duration of illness of 21 days and the development of respiratory symptoms in 28 patients.

Background aims. The potential protective effects of mesenchymal stromal cells (MSCs) on some kidney diseases has been reported. However, the effect of MSCs on doxorubicin-induced nephropathy is still poorly understood. Methods. Rats with doxorubicin-induced kidney injuries were treated with human cord-derived MSCs. Human MSCs were first labeled with 5-bromo-2'-deoxyuridine to track their homing in kidneys after infusion. Results. Alleviation of proteinuria, decreased serum albumin, alleviation of lipid disorders and histologic alterations were found in rats 4 weeks after treatment with MSCs, particularly in rats that were given repeat doses. Decreases in serum levels of interleukin-6, tumor necrosis factor-a and prostaglandin E2 and decreases in messenger RNA levels of kidney tissue cylooxygenase-2 and EP4 were found in MSC-treated rats. MSC-treated rats also displayed an increase in serum interleukin-10 levels. Conclusions. These results indicate that MSCs ameliorate doxorubicin-induced kidney injuries and inflammation, suggesting a potential clinical treatment for inflammatory kidney diseases. [ABSTRACT FROM AUTHOR]

Objective: To explore the features and risk factors of bacterial skin infections (BSIs) in hospitalized patients with bullous pemphigoid (BP)., Methods: Records were retrospectively reviewed for 110 hospitalized patients with BP admitted to Peking University First Hospital between 2013 and 2019. Bacterial species and drug resistance were assessed, and then the underlying risk factors for BSIs were evaluated., Results: Infections were present in 40% (44/110) of the patients. Staphylococcus aureus (72.7%, 32/44) was the most common bacterium, and it was highly resistant to penicillin (81.3%, 26/32), erythromycin (62.5%, 20/32), and clindamycin (56.3%, 18/32), but 100.0% sensitive to vancomycin and tigecycline. Coronary heart disease (P = .02; odds ratio [OR], 12.68), multisystem comorbidities (P = .02; OR, 3.67), hypoalbuminemia (P = .04; OR, 3.70), high levels of anti-BP180 antibodies (>112.4 U/mL; P = .003; OR, 6.43), and season (spring: reference; summer: P = .002; OR, 23.58; autumn: P = .02; OR, 12.19; winter: P = .02; OR, 13.19) were significantly associated with BSIs., Conclusions: Hospitalized patients with BP had a high incidence of BSIs, and those patients with underlying risk factors require careful management to prevent and control BSIs., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)