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The traditional Power Flow Calculation (PLF) method of the distribution network is affected by the accuracy of model parameters, the convergence of the solution method, and other factors. At the same time, the accuracy of the PLF of the distribution network will directly affect the optimization effect of the distribution network. In this paper, a data-driven power flow analysis and the volt/var optimization control strategy for the distribution network are proposed. Firstly, the CatBoost machine learning model for the distribution network power flow analysis is proposed, and the nonlinear mapping relationship between the distribution network state and power flow results is described from the data-driven perspective. Secondly, the influence of PhotoVoltaic (PV) power supply on the distribution network is analyzed, and the volt/var optimization model based on PV power supply is proposed. Then, the volt/var optimization strategy of the distribution network based on data-driven power flow analysis is proposed to ensure the safe and stable operation of the distribution network voltage and reduce the operating network loss of the distribution network without the need for network parameters and other information. Finally, the IEEE 33 node system is used to verify the effectiveness of the proposed strategy, the results of the example show that the data-driven PLF method can accurately perceive the voltage and loss of the distribution network. The proposed optimization strategy can stabilize the voltage of the distribution network in the range of 0.95–1.05, and the loss of the distribution network is reduced from 6.879 MWh to 3.369 MWh.

Due to the fluctuation of PV power, it is difficult to keep the active power of the PV grid-connected inverter constant. To address the above problems, this paper proposed a new three-level integrated photovoltaic storage machine consisting of a T-type three-level DC/AC converter, a three-level Boost converter and a three-level bi-directional DC/DC converter and related control strategies. The three-level structure allowed for lower switching losses resulting in higher system efficiency and wider voltage range adaptability. In terms of control, frequency differentiation and deviation control were introduced in the control of the energy storage DC/DC converter to achieve frequency regulation of the transient/static support of the active power of the parallel network. The simulation and experiment show that when the frequency fluctuation range is 50.02~49.97 Hz (meeting the national standard), the new optical storage all-in-one machine proposed in this paper can operate stably and be easily realized.

ObjectiveTo investigate the biological function and molecular mechanism of long non-coding RNA Linc‑pint in colorectal cancer.MethodsQuantitative real‑time quantitative （qRT‑PCR） was performed to detect the expression level of Linc‑pint in 31 pairs of colorectal cancer tumor and adjacent normal tissues； correlation between the expression level of Linc‑pint and the clinicopathological characteristics was analyzed by the chi‑square test. Kaplan-Meier survival analysis was used to assess the relationship between Linc‑pint expression level and the prognosis of patients. Cox regression model was used to analyze the relationship between clinicopathological characteristics and the prognosis of patients. Expression level of Linc‑pint were detected by qRT‑PCR in 5 common colorectal cancer cell lines. Effect of Linc‑pint on cell proliferation， invasion and migration was measured by cell counting kit‑8 assay， Transwell assay and harvested xenografts from nude mice. qRT‑PCR was performed to detect the expression level of Linc‑pint's target gene micro RNA（miR）‑21 in 31 pairs of colorectal cancer tumor tissues and adjacent normal tissues. Pearson correlation coefficient was used to assess the correlation between Linc‑pint and miR‑21. qRT‑PCR was used to detect the expression of overexpression of Linc‑pint on miR‑21 in colorectal cancer cells.ResultsExpression level of Linc‑pint in normal tissues （3.95±1.16） was significantly higher than that in colorectal cancer tissues （2.74±0.95） （t=6.17， P

Engineering survey is an important technology applied in the quality management of construction engineering. By conducting engineering survey, it can provide necessary data support and measurement methods for the early exploration, mid-term construction, and later acceptance quality management of construction engineering. In the process of construction quality management, how to apply the engineering measurement technology reasonably becomes an urgent problem to be solved. This article will give an overview of engineering survey, and describe the important role of it, and give some opinions and suggestions.

Abstract Background New strategies for high-throughput sequencing are constantly appearing, leading to a great increase in the number of completely sequenced genomes. Unfortunately, computational genome annotation is out of step with this progress. Thus, the accurate annotation of these genomes has become a bottleneck of knowledge acquisition. Results We exploited a proteogenomic approach to improve conventional genome annotation by integrating proteomic data with genomic information. Using Shigella flexneri 2a as a model, we identified total 823 proteins, including 187 hypothetical proteins. Among them, three annotated ORFs were extended upstream through comprehensive analysis against an in-house N-terminal extension database. Two genes, which could not be translated to their full length because of stop codon 'mutations' induced by genome sequencing errors, were revised and annotated as fully functional genes. Above all, seven new ORFs were discovered, which were not predicted in S. flexneri 2a str.301 by any other annotation approaches. The transcripts of four novel ORFs were confirmed by RT-PCR assay. Additionally, most of these novel ORFs were overlapping genes, some even nested within the coding region of other known genes. Conclusions Our findings demonstrate that current Shigella genome annotation methods are not perfect and need to be improved. Apart from the validation of predicted genes at the protein level, the additional features of proteogenomic tools include revision of annotation errors and discovery of novel ORFs. The complementary dataset could provide more targets for those interested in Shigella to perform functional studies.

Abstract Background Tuberculosis is an infectious bacterial disease in humans caused primarily by Mycobacterium tuberculosis, and infects one-third of the world's total population. Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine has been widely used to prevent tuberculosis worldwide since 1921. Membrane proteins play important roles in various cellular processes, and the protein-protein interactions involved in these processes may provide further information about molecular organization and cellular pathways. However, membrane proteins are notoriously under-represented by traditional two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and little is known about mycobacterial membrane and membrane-associated protein complexes. Here we investigated M. bovis BCG by an alternative proteomic strategy coupling blue native PAGE to liquid chromatography tandem mass spectrometry (LC-MS/MS) to characterize potential protein-protein interactions in membrane fractions. Results Using this approach, we analyzed native molecular composition of protein complexes in BCG membrane fractions. As a result, 40 proteins (including 12 integral membrane proteins), which were organized in 9 different gel bands, were unambiguous identified. The proteins identified have been experimentally confirmed using 2-D SDS PAGE. We identified MmpL8 and four neighboring proteins that were involved in lipid transport complexes, and all subunits of ATP synthase complex in their monomeric states. Two phenolpthiocerol synthases and three arabinosyltransferases belonging to individual operons were obtained in different gel bands. Furthermore, two giant multifunctional enzymes, Pks7 and Pks8, and four mycobacterial Hsp family members were determined. Additionally, seven ribosomal proteins involved in polyribosome complex and two subunits of the succinate dehydrogenase complex were also found. Notablely, some proteins with high hydrophobicity or multiple transmembrane helixes were identified well in our work. Conclusions In this study, we utilized LC-MS/MS in combination with blue native PAGE to characterize modular components of multiprotein complexes in BCG membrane fractions. The results demonstrated that the proteomic strategy was a reliable and reproducible tool for analysis of BCG multiprotein complexes. The identification in our study may provide some evidence for further study of BCG protein interaction.

In engineering practice, various types of pile foundations are commonly employed to mitigate the impact of differential frost heave on structures in cold regions. However, the studies on how pile material properties influence the thermo-hydro-mechanical coupling fields during the freezing of the pile–soil system remain limited. To address this, a finite element model was developed to simulate the response of the pile–soil system under unidirectional freezing conditions. The numerical model in simulating ground temperature field and frost heave was first verified by comparison with experimental results. Then, the simulations for piles made of different materials, specifically steel and concrete piles at field scale, were conducted to obtain real-time temperature, moisture, and displacement fields during the freezing process. The results demonstrate that pile–soil systems of the two materials exhibit clearly different freezing patterns. The thermal conductivity of concrete, being similar to that of the surrounding soil, results in a unidirectional freezing pattern of soil around concrete piles, with the frost depth line parallel to the frost heave surface, forming a "一-shaped" freezing zone. In contrast, the high thermal conductivity of steel piles significantly accelerates the freezing rate and increases the frost depth in the surrounding soil, leading to both vertical and horizontal bidirectional freezing around the piles, creating an "inverted L-shaped" freezing zone. This bidirectional freezing generates greater tangential frost heave forces, pile frost jacking, and soil displacement around piles compared to concrete piles under identical freezing conditions. The numerical simulation also identifies the critical hydraulic conductivity at which moisture migration in the frozen soil layer ceases and describes the variation of relative ice content with temperature. These findings offer valuable insights into considering soil frost heave and pile displacement when using steel for foundation construction in cold regions, providing guidance for anti-frost heave measures in such environments. [ABSTRACT FROM AUTHOR]

The present study investigates the relationship between the near-infrared (NIR) spectral characteristics of cross-linked polyethylene (XLPE) insulation materials and their macroscopic properties, with the aim of establishing a reference framework for non-destructive material aging analysis. Accelerated thermal aging tests were conducted on samples of XLPE cables. These samples underwent Fourier-transform infrared spectroscopy (FTIR), elongation at break (EAB), and tensile strength (TS) tests. The temporal variation curves of the carbonyl index (CI), EAB, and TS were obtained at aging temperatures of 105 °C, 135 °C, 155 °C, and 180 °C. Additionally, NIR spectroscopy was performed on the aged XLPE samples, producing absorbance curves corresponding to different aging times at these temperatures. The absorption peaks of 'C-H (-CH2-)' (1730 nm/1764 nm) were analyzed to determine their temporal variation patterns. Finally, a correlation analysis was conducted between the NIR results and those of the FTIR, EAB, and TS tests, revealing numerical relationships between NIR characteristic peaks and FTIR, EAB, and TS data. These quantified correlations demonstrate that NIR can effectively represent macroscopic mechanical properties, thereby simplifying the procedures for monitoring material aging and providing valuable results without requiring destructive testing. Results indicate that there is a certain feasibility in replacing traditional cable aging tests with NIR. [ABSTRACT FROM AUTHOR]

A laser welding with wire filler feeding was developed to replace traditional arc welding process for joining aluminium alloy railcar body components. A three-dimensional (3D) thermo-elastic-plastic finite element (FE) model was applied to compute the plastic strains of weld zone in a downsized aluminium alloy plate with butt-joint, T-joint and fillet-joint configurations, respectively, combined with corresponding experimental validations. The achieved plastic strains at the weld zone were then input as inherent strain loadings into elastic structural FE model of fully sized aluminium alloy railcar body components to predict the welding induced distortion with the experimentally measured out-of-plane distortions. The experimentally validated FE model was then further applied for optimizing the inverse pre-deformation of plates to counteract the welding induced deformation, finally to mitigate the welding distortion issues. [ABSTRACT FROM AUTHOR]