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The paper presents a new model of the thermal rotor protection 49R on synchronous generators with self-excitation with the influence of generator negative sequence protection 46I2. The purpose of the analysis is to solve the problem of simultaneous occurrence of rotor overload due to excitation current and rotor overload due to the inverse component of the stator current. The numerical protections are designed to operate independently of each other, and therefore the residual thermal capacity of the copper windings is not defined with higher precision. A mathematical model that integrates these two protections is given and described.

Inverter-based resources (IBRs) exhibit different short-circuit characteristics compared to traditional synchronous generators (SGs). Hence, increased uptake of IBRs in the power system is expected to impact the performance of traditional protective relay schemes—set under the assumption of a SG-dominated power system. Protection engineers need to study these challenges and develop remedial solutions ensuring the effectiveness of system protection under higher levels of IBRs. To address this need, this paper studies the impact of IBRs on a variety of protective relay schemes including line distance protection, memory-polarized zero sequence directional protective relay element, negative sequence quantities-based protection, line current differential protection, phase comparison protection, rate-of-change-of-frequency, and power swing detection. For each protection function, potential misoperation scenarios are identified, and recommendations are provided to address the misoperation issue. The objective is to provide an improved understanding of the way IBRs may negatively impact the performance of traditional protection schemes as a first step towards developing future remedial solutions ensuring effective protection under high share of IBRs.

Analysis the wiring of head and tail pully driving & bidirectional 6KV motor，and found the reason of negative phase sequence over current protection malfunction did occur when the motor ran in the reverse direction , then compared the solution methods to make sure which one is better. At last use the method that change the sampling program to make the motor negative phase sequence over current protection wil in effect.

Current differential protection, using either phase currents or negative-sequence components, is commonly applied for the sensitive protection of power transformers. However, this method proves insufficient for autotransformers, particularly when their tertiary winding is fully loaded, as demonstrated in this paper. To address this limitation, the authors’ previously proposed negative-sequence integral approach for power transformers has been adapted and evaluated for three-winding autotransformers. The results show that this integral protection offers significantly higher sensitivity than current differential schemes while maintaining security during external faults with current transformer saturation.

A data-mining-based intelligent anti-islanding detection scheme for distributed generation (DG) protection has been presented. The process starts at deriving highly involved features using discrete Fourier transform-based pre-processor at the DG end. The features derived include both positive and negative sequence quantities and related features. Once the features are retrieved, the decision tree is trained to build a data-mining model for identifying the islanding events from non-islanding situations, including disturbances close to islanding conditions. The proposed anti-islanding relay is extensively tested on simulation model and provides encouraging results considering wide variations in operating conditions. Further, the validation is extended on real-time digital simulator module to test the efficacy of the proposed anti-islanding relay. The test results indicate that the proposed anti-islanding relay can reliably detect islanding conditions while meeting the speed criteria.

Lipopolysaccharide (LPS) O-antigen (O-Ag) is known to limit antibody binding to surface antigens, although the relationship between antibody, O-Ag and other outer-membrane antigens is poorly understood. Here we report, immunization with the trimeric porin OmpD from Salmonella Typhimurium (STmOmpD) protects against infection. Atomistic molecular dynamics simulations indicate this is because OmpD trimers generate footprints within the O-Ag layer sufficiently sized for a single IgG Fab to access. While STmOmpD differs from its orthologue in S . Enteritidis (SEn) by a single amino-acid residue, immunization with STmOmpD confers minimal protection to SEn. This is due to the OmpD-O-Ag interplay restricting IgG binding, with the pairing of OmpD with its native O-Ag being essential for optimal protection after immunization. Thus, both the chemical and physical structure of O-Ag are key for the presentation of specific epitopes within proteinaceous surface-antigens. This enhances combinatorial antigenic diversity in Gram-negative bacteria, while reducing associated fitness costs. The O-antigen of LPS is known to limit the binding of antibody to bacterial surface antigens. Here the AUs show that the chemical and physical structure of the O-antigen are central factors in limiting the exposure of surface antigens to antibodies during Salmonella infection, thus defining their protective qualities.

Pathogenicity of many Gram-negative bacteria relies on the injection of effector proteins by type III secretion into eukaryotic cells, where they modulate host signaling pathways to the pathogen's benefit. One such effector protein injected by Xanthomonas into plants is AvrBs3, which localizes to the plant cell nucleus and causes hypertrophy of plant mesophyll cells. We show that AvrBs3 induces the expression of a master regulator of cell size, upa20, which encodes a transcription factor containing a basic helix-loop-helix domain. AvrBs3 binds to a conserved element in the upa20 promoter via its central repeat region and induces gene expression through its activation domain. Thus, AvrBs3 and likely other members of this family provoke developmental reprogramming of host cells by mimicking eukaryotic transcription factors.

The insulin-like growth factor (IGF) signaling pathway has long been established as playing critical roles in skeletal muscle development. However, the underlying regulatory mechanism is poorly understood. Recently, a large family of small RNAs, named microRNAs (miRNAs), has been identified as key regulators for many developmental processes. Because miRNAs participate in the regulation of various signaling pathways, we hypothesized that miRNAs may be involved in the regulation of IGF signaling in skeletal myogenesis. In the present study, we determined that the cell-surface receptor IGF-1R is directly regulated by a muscle-specific miRNA, microRNA-133 (miR-133). A conserved and functional binding site for miR-133 was identified in the 3'untranslated region (3'UTR) of IGF-1R. During differentiation of C2C12 myoblasts, IGF-1R protein, but not messenger RNA (mRNA) expression, was gradually reduced, concurrent with the upregulation of miR-133. Overexpression of miR-133 in C2C12 cells significantly suppressed IGF-1R expression at the posttranscriptional level. We also demonstrated that both overexpression of miR-133 and knockdown of IGF-1R downregulated the phosphorylation of Akt, the central mediator of the PI3K/Akt signaling pathway. Furthermore, upregulation of miR-133 during C2C12 differentiation was significantly accelerated by the addition of IGF-1. Mechanistically, we found that the expression of myogenin, a myogenic transcription factor reported to transactivate miR-133, was increased by IGF-1 stimulation. Our results elucidate a negative feedback circuit in which IGF-1-stimulated miR-133 in turn represses IGF-1R expression to modulate the IGF-1R signaling pathway during skeletal myogenesis. These findings also suggest that miR-133 may be a potential therapeutic target in muscle diseases.

An anthropic pressure is exerted on water matrices due to the discharge of partially treated or untreated wastewater. Among the micropollutants found are heavy metals (HMs) which can induce the co-selection of antibiotic–heavy metal-resistant organisms, posing a serious public health problem. This study aimed to detect and characterize cadmium and carbapenem-resistant non-fermenting Gram-negative bacilli (NFGNB) isolated from urban and hospital wastewater. In this study, 52 NFGNB were isolated from urban wastewater (UWW, n = 24) and hospital wastewater (HWW, n = 28). Pseudomonas spp. (n = 32, 61.5%) and Acinetobacter spp. (n = 7. 13.5%) were the most frequently isolated. The MAR index varied from 0 (pansusceptible) to 0.81 (resistant to 13/16). Nine strains were resistant to carbapenems. PCR screening indicated that the A. baumannii S57 strain produced an OXA-23 carbapenemase, while the P. mendocina S119 produced a VIM MβL. A total of 37 strains had MICs of cadmium ≥ 700 µg/ml. This study explored the potential reservoirs of both types of effluent to harbor opportunistic bacteria considered to be emerging pathogens of the MDR cadmium-resistant phenotype constituting a double reservoir for the propagation of antibiotics (ATBs) and HM resistance genes.

Multidrug resistance mediated by β-lactamase in Gram-negative bacilli is a serious public health problem. Sewers are considered reservoirs of multiresistant bacteria due to presence of antibiotics that select them and favor their dissemination. The present study evaluated the antibiotic resistance profile and β-lactamases production in Gram-negative bacilli isolates from hospital sewage and urban wastewater treatment plants (UWWTP) in Brazil. Bacteria were isolated and identified with biochemical tests. Antibiotic susceptibility testing was performed by the disk-diffusion method and detection of extended-spectrum β-lactamase and carbapenemases by enzymatic inhibitor and conventional PCR. Differences in resistance to amoxicillin clavulanic, aztreonam, cefepime, and cefotaxime were observed in hospital sewage compared with urban sewage ( p  < 0.05). The multidrug-resistant phenotype was observed in 33.3% of hospital sewage isolates ( p  = 0.0025). β-lactamases genes were found in 35.6% of isolates, with the most frequent being bla KPC and bla TEM (17.8%), and bla SHV and bla CTX-M (13.3% and 8.9%, respectively). The data obtained are relevant, since the bacteria detected are on the priority pathogens list from the World Health Organization and hospital sewage could be released untreated into the municipal collection system, which may favor the spread of resistance. Changes in hospital sewage discharge practices, as well as additional technologies regarding effluent disinfection in the UWWTP, can prevent the spread of these bacteria into the environment and negative impact on water resources.