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Abstract Background Posterior fossa malformation (PFM) is a relatively uncommon prenatal brain malformation. Genetic diagnostic approaches, including chromosome karyotyping, copy number variant (CNV) testing, and whole-exome sequencing (WES), have been applied in several cases of fetal structural malformations. However, the clinical value of appropriate genetic diagnostic approaches for different types of PFMs has not been confirmed. Therefore, in this study, we aimed to analyze the value of different combined genetic diagnostic approaches for various types of fetal PFMs. Methods This retrospective study was conducted at Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital. Fifty-one pregnant women diagnosed with fetal PFMs who underwent genetic testing in our hospital from January 1, 2017 to December 31, 2022 were enrolled; women with an isolated enlarged cisterna magna were excluded. All participants were categorized into two groups according to the presence of other abnormalities: isolated and non-isolated PFMs groups. Different combined approaches, including karyotype analysis, CNV testing, and trio-based WES, were used for genetic analysis. The detection rates of karyotype analysis, CNV testing, and WES were measured in the isolated and non-isolated groups. Results In isolated PFMs, pathogenic/likely pathogenic (P/LP) CNVs were detected in four cases (36.36%, 4/11), whereas G-banding karyotyping and WES showed negative results. In non-isolated PFMs, a sequential genetic approach showed a detection rate of 47.5% (19/40); karyotyping revealed aneuploidies in five cases (16.67%, 5/30), CNV testing showed P/LP CNVs in five cases (16.13%, 5/31), and WES identified P/LP variants (in genes CEP20, TMEM67, OFD1, PTPN11, ARID1A, and SMARCA4) in nine cases (40.91%, 9/22). WES showed a detection rate of 83.33% (5/6) in fetuses with Joubert syndrome. Only six patients (five with Blake’s pouch cyst and one with unilateral cerebellar hemisphere dysplasia) survived. Conclusions We recommend CNV testing for fetuses with isolated PFMs. A sequential genetic approach (karyotyping, CNV testing, and WES) may be beneficial in fetuses with non-isolated PFMs. Particularly, we recommend WES as the first-line genetic diagnostic tool for Joubert syndrome.

The cotton-picking robot needs to locate the target object in space in the process of picking in the field and other outdoor strong light complex environments. The difficulty of this process was binocular matching. Therefore, this paper proposes an accurate and fast binocular matching method. This method used the deep learning model to obtain the position and shape of the target object, and then used the matching equation proposed in this paper to match the target object. Matching precision of this method for cotton matching was much higher than that of similar algorithms. It was 54.11, 45.37, 6.15, and 12.21% higher than block matching (BM), semi global block matching (SGBM), pyramid stereo matching network (PSMNet), and geometry and context for deep stereo regression (GC-net) respectively, and its speed was also the fastest. Using this new matching method, the cotton was matched and located in space. Experimental results show the effectiveness and feasibility of the algorithm.

K403 nickel-base superalloy is widely used in the manufacture of aero-engine turbine blades because of its excellent properties at room temperature and high temperature. In order to solve the problem of turbine blade crack defects caused by long-term service in complex working conditions，in this work，two different processes of （tungsten inert gas，TIG） welding and laser cladding were used to repair the blade cracks，and the microstructure and properties of the repaired region were studied. The influence of TIG welding and laser cladding repairing on microstructure，mechanical properties and failure behavior was analyzed. The results show that the microcracks tend to occur near the repair interface using the TIG welding repairing process，which are mainly caused by carbides and low melting point eutectic structure. The grain and structure of the repaired area by laser cladding repair technology are more uniform，and the microcrack defects can be easier to control. The comprehensive mechanical properties of the samples repaired by laser cladding are obviously higher than those repaired by TIG welding repairing process，and the samples repaired by laser cladding have better process stability. The tensile strengths of the samples using the laser cladding repair process and the TIG welding repair process at room temperature have reached 87.44% and 69.22% of the strength of K403 base material，respectively. According to the failure analysis results，the tensile fracture at room temperature in the repaired region presents mixed fracture characteristics，and the tensile fracture at high temperature presents intergranular fracture characteristics. Microcracks in the repaired area，local liquid phase deficiency defects and carbide structure are the main reasons of failure. The laser cladding technology has the advantages of heat source concentration and smaller heat affected zone，which can effectively restrain the defects and refine the microstructure. Therefore，the laser cladding repair process is used to repair the edge plate crack damage generated during the blade test run. After fluorescence and kerosene-chalk detection，the repairing process meets the relevant reuse requirements.

Selective laser melting（SLM）can achieve nearly net-shape complex parts of GH3536 alloy，and its high temperature mechanical properties are important indicators for safe service. The effect of heat treatment on microstructure and high temperature tensile properties of SLM GH3536 alloy were studied. The heat treatment at 1225 ℃ for 1 h was carried out to explore the regulation mechanism of microstructure and properties. The results show that heat treatment can effectively eliminate the cellular subgrain structure inside the grains，which significantly enhances the dislocation slip ability. The tensile elongations at room temperature，650 ℃ and 815 ℃ are increased by 75%，92% and 683%，respectively. In addition，the decrease of the aspect ratio of the columnar grains significantly reduces the anisotropy in the heat-treated sample. The fracture analysis shows that the fracture mode of the heat-treated sample changes from intergranular fracture to mixed fracture with the increase of tensile environment temperature.

With the development of UAV technology, UAVs have the advantages of convenience, speed, and small size. However, when faced with a complex task environment, some traditional artificial intelligence algorithms will significantly increase computation time, and the algorithms that perform better in time performance often fail to adapt to the type and number of random tasks to be assigned. In this paper, we combine the Hungarian algorithm with improving the LightGBM model, simulate the implementation in various task scenarios, and verify that the improved LightGBM model completes the intelligent assignment of multiple UAVs without increasing time cost compared to the classical algorithm through comparative analysis. It is shown that the improved LightGBM model has an average time of 26.39s for 10 runs, which is higher than 16.91s for NSGA-II and 14.73s for PESA, but lower than 46.92s for SPEA2 and 50.01s for SPGA2. For a non-real-time assignment system, a better mission intelligence assignment at a certain time cost scheme is more in line with the system’s performance requirements. Therefore, the improved LightGBM model in this paper can obtain better solutions than the other four algorithms in solving the multi-objective multi-UAV task intelligence assignment problem, and the solution set coverage is larger than several other algorithms. This indicates that the algorithm studied in this paper is feasible in solving the multi-objective multi-UAV task intelligence assignment problem, and it also has some reference significance for solving the multi-objective problem and improving the coverage of the multi-objective solution set.

With the rapid development of society, people’s awareness of environmental protection continues to strengthen, countries also pay more and more attention to environmental protection, whether from the national policy or from the green development of enterprises in the future, the improvement of power plant operation efficiency is imperative. Among them, improving the operation efficiency of thermal power plants is the top priority, and it is also an important link of national economic transformation. The design of electrical part is an important part of improving the operation efficiency of thermal power plants. 2x300MW thermal power plant is designed, including the power plant electrical main wiring design, plant power design, the main circuit of the power plant short-circuit calculation, and it choose the electrical stability and thermal stability of the better electrical equipment. The short circuit calculation of the main circuit of the power plant is carried out and preliminary planning of the secondary circuit scheme is made. A power plant with higher operating efficiency is designed. While improving the operation and economic efficiency of the power plant, it also ensures the reliability, stability and economy of the power plant.

Background As socioeconomic status and population health develop, death patterns and disease spectrum have changed. The impact of diseases on life expectancy have changed as well. Objective To analyze the change in life expectancy and disease spectrum in residents of Jing'an District in Shanghai from 2016 to 2021. Methods Population data and mortality data of permanent residents in Jing'an District of Shanghai from 2016 to 2021 were collected from the Public Security Bureau of Jing'an District, and the Jing'an District Mortality Surveillance System. The ICD-10 was used to categorize the underlying causes of death. The Abridged Life Tables and Arriaga's decomposition method were used to analyze the impacts of age groups and causes of death on life expectancy. Results The life expectancy of these residents from 2016 to 2021 ranged from 83.68 to 84.40 years, which increased by 0.72 years in 2021 compared with that of 2016. The life expectancy of male residents was 81.47 to 82.15 years, demonstrating an increase of 0.68 years during the period. The life expectancy was 85.95 to 86.74 years for female residents, showing an increase of 0.79 years during the period. The decrease of mortality rate in 65 to 84 age group contributed 83.29% to the increase of the life expectancy (0.60 years) , while the decrease of mortality rate in 15 to 44 age group contributed -17.18% to the increase of the life expectancy (-0.12 years) . The largest contribution to the increase of life expectancy was the mortality reduction in cancer, followed by that in respiratory disease, which contributed 56.20% and 53.55%, respectively. The largest contribution to the decrease of life expectancy was increased mortality due to injuries and poisoning, followed by that due to endocrine, nutritional and metabolic diseases, which contributed -35.69% and -17.25%, respectively. Conclusion The life expectancy of residents in Jing'an District from 2016 to 2021 was 83.68 to 84.40 years, seeing an increase of 0.72 years. The increase of life expectancy was mainly attributed to the decrease of mortality in 65 to 84 age group and the decrease of mortality due to cancer. However, the increase of mortality due to injuries and poisoning had negative contribution.

In order to study the corrosion behavior of 316L and 2205 stainless steels and explore their application prospects in underwater production systems, the corrosion rate, electrochemical behavior and pitting corrosion resistance of 316L and 2205 stainless steels were analyzed and compared by using long period immersion test, cyclic polarization curve, potentiostatic polarization and electrochemical impedance spectroscopy (EIS) with the help of scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Results showed that the corrosion resistance of 2205 duplex stainless steel was better than that of 316L austenitic stainless steel in the simulated seawater environment with high CO2 content. Compared with 316L stainless steel, 2205 stainless steel had larger passive region, lower passive current density and larger passive film resistance. The high corrosion resistance of 2205 stainless steel was attributed to its higher pitting resistance equivalent (PREN) value and fewer inclusions, which enabled the passive film on the surface of 2205 stainless steel more stable and less prone to localized damage.

ObjectiveTo analyze the epidemiological characteristics of senile dementia death in Jing’an District from 2016 to 2020， as well as the trends of mortality， standardized mortality， years of life lost （YLL） due to early death， years lived with disability （YLD）， and disability-adjusted life year （DALY）， and to provide scientific basis for the prevention and control of senile dementia.MethodsThe distribution of senile dementia in terms of gender， age， marital status and education level was investigated in the senile dementia death cases from 2016 to 2020 in Jing’an District. The YLL， YLD， DALY and their rates of the residents of Jing’an District from 2016 to 2020 were calculated by using Global Burden of Disease （GBD 2019） research method and results in combination with the corresponding population data.ResultsCompared to those without dementia， deaths with dementia were more likely to be female， more likely to be over 80 years old， less likely to be married， and more likely to have education level under middle school. Among the deaths with dementia， only 27.70% of the primary cause of death was dementia， and the other main causes were cerebrovascular disease， coronary heart disease and diabetes mellitus， which accounted for 25.54%， 17.81% and 7.28%， respectively. There was a significant gender difference in the burden of disease on senile dementia in Jing’an District. Mortality， standardized mortality， YLL， YLD and DALY rates of females were higher than those of males. The burden of disease on senile dementia increased with age. The change trend of mortality and YLL rate from 2016 to 2020 was not statistically significant， while the YLD rate and DALY rate showed an upward trend， which was statistically significant.ConclusionAs the life span of residents in Jing’an District increases and the population aging deepens， the burden of disease on senile dementia is still heavy. This requires extensive attention of the whole society， and active exploration of prevention and control strategies and measures for senile dementia， so as to improve the life quality of patients and reduce the burden of disease.

A method for measuring (n,α) reaction cross sections of the gas sample induced by fast neutrons using a gridded ionization chamber (GIC) was established. There are several advantages using the GIC to measure gas samples. With this method, the (n,α) reaction cross sections of inert gases which are hard to exist as a solid can be measured. And the (n,α) reaction cross section for α particle emitting in all directions can be directly measured by using the gas sample. Furthermore, compared with using solid samples, using gas samples have far more nuclei in the measurement samples. Therefore, it is feasible to use neutron source with a better energy resolution to measure the resonance cross sections with gas sample. However, there are many problems to be solved when measuring (n,α) reaction cross section of gas sample by using the GIC. On the one hand, the nuclear reaction event will be affected by the wall effect, when the nuclear reaction is generated near the electrodes of the GIC or at the edge of the electric field. The wall effect will cause the measured event to locate outside the event area which cannot be counted. Not only is the number of nuclei of the gas samples involved in the (n,α) reaction difficult to determine, but the number of events, which are affected by the background or located below the threshold, is also difficult to count. On the other hand, the neutron fluence involved in the measurement of (n,α) reaction cross section of gas sample is difficult to measure. Aiming at solving the problems of the determination of the sample nuclei number, the measurement of neutron fluence, and the selection of events, which are all difficult for the gas sample, this method included three steps: First, simulation calculation was performed to select a suitable effective volume of the gas samples, so that the event is free of background and easy to be counted. Second, the neutron collimator and the timing information of cathode and anode signals were used to select and count the events generated in the effective volume of the gas sample. Third, combining the fission fragment measurement of the 238U(n,f) reaction and the simulation based on SuperMC, the neutron fluence through the effective volume was obtained. Measurements of relative cross sections of the 14N(n,α0) reaction using gas sample were performed at En=471, 487, 500, 512, 529, and 545 MeV. The results are in good agreement with those of ENDF/BⅧ.0 which verified the present measurement method.

As a kind of proteolytic enzyme extracted from earthworms, lumbrokinase has been used as an antithrombotic drug clinically. Nevertheless, its potential in anti-cancer, especially in anti-non-small cell lung cancer (NSCLC), as a single form of treatment or in combination with other therapies, is still poorly understood. In this study, we explored the anti-tumor role and the responsive molecular mechanisms of lumbrokinase in suppressing tumor angiogenesis and chemoresistance development in NSCLC and its clinical potential in combination with bevacizumab and chemotherapeutics. Lumbrokinase was found to inhibit cell proliferation in a concentration-dependent manner and caused metastasis suppression and apoptosis induction to varying degrees in NSCLC cells. Lumbrokinase enhanced the anti-angiogenesis efficiency of bevacizumab by down-regulating BPTF expression, decreasing its anchoring at the VEGF promoter region and subsequent VEGF expression and secretion. Furthermore, lumbrokinase treatment reduced IC50 values of chemotherapeutics and improved their cytotoxicity in parental and chemo-resistant NSCLC cells via inactivating the NF-κB pathway, inhibiting the expression of COX-2 and subsequent secretion of PGE2. LPS-induced NF-κB activation reversed its inhibition on NSCLC cell proliferation and its synergy with chemotherapeutic cytotoxicity, while COX-2 inhibitor celecoxib treatment boosted such effects. Lumbrokinase combined with bevacizumab, paclitaxel, or vincristine inhibited the xenograft growth of NSCLC cells in mice more significantly than a single treatment. In conclusion, lumbrokinase inhibited NSCLC survival and sensitized NSCLC cells to bevacizumab or chemotherapeutics treatment by targeted down-regulation of BPTF/VEGF signaling and inactivation of NF-κB/COX-2 signaling, respectively. The combinational applications of lumbrokinase with bevacizumab or chemotherapeutics are expected to be developed as promising candidate therapeutic strategies to improve the efficacy of the original monotherapy in anti-NSCLC. [ABSTRACT FROM AUTHOR]