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The dilution ratio of the Ni coating prepared by the laser cladding under the assistance of the follow-up feeding pulsed current was optimized by combining back propagation (BP) neural network and genetic algorithm. The model was trained according to the results of the 6-factor 3-level orthogonal experiments. A BP genetic neural network forecast model between cladding parameters (laser power, scanning speed, powder feeding rate, pulsed current, pulse frequency and pulse width) and dilution ratio of coating was constructed. On this basis, technological parameters under the target dilution ratio of the coating were optimized by a genetic algorithm. Results demonstrated that the predicted results of the model are very close to the experimental results in term of dilution ratio of the coating, with a relative error no higher than 2.63%. This demonstrates that the model is reliable and effective. The optimal technological parameters are gained when the dilution ratio of the coating is 17.5%, including laser power=1926.3 W, laser scanning speed =·s-1, powder feeding rate= ·min-1, average pulsed current =, pulse frequency=445.6 Hz, pulse width= 108.4 μs.

AimsTo identify potential risk factors for myopia in children and adolescents and assess the credibility of each evidence, providing reference for the development of myopia prevention strategies.MethodsWe searched PubMed, Web of Science and Embase databases from inception to April 2022 to find systematic reviews or meta-analyses investigating the relationship between potential risk factors and myopia, and conducted an umbrella review. We recalculated the pooled effect sizes and 95% CIs of each potential risk factor through random-effects model, and reported its 95% prediction interval and between-study heterogeneity. Small-study effect and excess of significance bias were assessed to reveal potential publication bias.ResultsTwelve publications were included in this umbrella review, including eight meta-analyses and four qualitative systematic reviews. Twenty-two factors were identified, of which 16 were analysed quantitatively. Ten factors showed statistically significant association with myopia. Myopia in one or two parents and per additional hour of time spend outdoors per week were rated as highly suggestive evidence. Near work and gender were evaluated as suggestive evidence. The other five factors are weak evidence.ConclusionsWe found several risk factors for myopia with different levels of evidence, of which parental myopia presented the strongest association with myopia in children and adolescents. Our findings contribute to a better understanding of the association between potential risk factors and myopia among children and adolescents and are important for informing parenting, education, clinical practice guidelines and public health policy.PROSPERO TRIAL REGISTRATION NUMBERCRD42022333053.

Background Allelopathy in rice (Oryza sativa) is a chemically induced response that is elevated by the exogenous application of chemical compounds and barnyard grass root exudates. An in-depth understanding of the response mechanisms of rice to chemical induction is necessary for the identification of target genes for increasing the allelopathic potential of rice. However, no previous studies have evaluated the transcriptomic changes associated with allelopathy in rice in response to barnyard grass exudates treatment. Thus, the aim of the present study was to reveal differentially expressed genes (DEGs) in allelopathic and non-allelopathic rice seedlings treated with barnyard grass exudates to identify target allelopathy genes. Results The inhibitory effect of the culture solutions on the allelopathic rice accession PI312777 (PI) and the non-allelopathic rice accession Lemont (LE) significantly increased (P

Background Although intraoperative palpation (IOP) is recommended during the sentinel lymph node biopsy (SLNB), its actual effect on SLNB remains unclear. Meanwhile, controversy exists regarding whether IOP is necessary for all SLNB. The study examined the impacts of IOP on SLNB and determined whether IOP is necessary for every operation. Methods 126 patients with early stage breast cancer underwent SLNB using Indocyanine green (n = 64) and Methylene blue (n = 62). Traced lymph nodes (TLNs) were resected, followed by the palpated lymph nodes (PLNs) surrounding the original TLNs. and we analyzed the results (with and without IOP) in terms of detection rate, number of removed SLNs and detection rate of metastatic SLNs. Results Without IOP, the detection rates of the two group were 90.6%(58/64), 88.7%(55/62), but with IOP, all the rates increased to 100% (p

Resin wafer electrodeionization is an energy-efficient technology for brackish water desalination without the use of harmful chemicals. In this study, the performance of resin wafer electrodeionization under different applied voltages and feed flow rates was measured for a feed salt concentration of 3.0 g L−1. The results indicated that a salt removal efficiency of 94% could be achieved. In addition, the removal kinetics of NaCl from the brackish water was studied via a first-order kinetic model. The maximum kinetic rate constant was found to be 0.091 min−1 at a cell voltage of 2.53 V. The kinetic rate constants varied with the applied voltage and feed flow rate to the 1.52 and 0.33 power respectively. Furthermore, the productivity and energy consumption were balanced by using the response surface methodology. The optimized operating conditions should be set at an applied voltage of 2.28 V per cell pair with a feed flow rate of 810 mL min−1, corresponding to a productivity of 55.5 L h−1 m−2 at an energy consumption of 0.66 kWh m−3. Compared with other water desalination processes, resin wafer electrodeionization can offer relatively a higher energy-efficient performance for the brackish water desalination.

The differentiation characteristics of landscape pattern affect the urban thermal environment. In this study, temperature characteristics of nine types of landscape in a national forest city, Longquan City, were analyzed by temperature inversion method and spatial analysis. The landscape pattern analysis method was used to explore the correlation of landscape metrics and the thermal environment from 1 km to 3.5 km. The results showed that the high and sub-high temperature zones of Longquan City were distributed in northeast-southwest, mainly composed of urban and rural residential areas. The low and sub-low temperature zone were mainly distributed in the northwest and southeast areas, mainly composed of public welfare forests. By calculating the mean land surface temperature of each landscape type in the area below 700 m above sea level, the temperature of coniferous forest, broadleaf forest, conifer-broadleaf forest, bamboo forest and water was relatively low, whereas that of shrub land, other forest land, cultivated land and construction land was relatively high. Through the analysis of landscape pattern and thermal environment, it was found that the class pattern index was more practical than the landscape pattern index. The correlation between thermal environment effect and construction land distribution reached 0.835, coniferous forest land, broadleaf forest land, coniferous-broadleaf forest land and water were the second, up to -0.5 to -0.4. The cooling effects of different forest types vaied across different spatial scales. Broadleaved forests and coniferous-broadleaved forests were more conducive to cooling at large scales. The larger the area and volume stock of forest land, the more likely it had the lowest land surface temperature.景观格局分异特征在相当程度上影响着城市热环境.本研究以国家森林城市龙泉市为对象,通过地温反演和空间分析反映9类景观温度特征,运用景观格局分析方法从1～3.5 km 6个尺度探索格局指数与热环境的相关性.结果表明: 龙泉市高温区及次高温区主要分布于东北至西南一带,以城乡居民地为主,低温区和次低温区主要分布于西北、东南区域,以公益林为主;对海拔700 m以下区域各景观类型地表温度的统计发现,针叶林地、阔叶林地、针阔混交林地、竹林地、水域的地温均值相对较低,灌木林地、其他林地、耕地、建设用地的地温均值相对较高;对景观格局与热环境的分析发现,类型水平格局指数较景观水平格局指数更具实际意义,建设用地与热环境的相关系数可达0.835,针叶林地、阔叶林地、针阔混交林地、水域次之,在-0.5～-0.4,不同林地类型的降温效果在空间尺度上的表达不同,阔叶林地、针阔混交林地更利于在大尺度上降温;林地的面积和蓄积量越大,越易出现地表温度低值.

To reveal the physiological effects of rice alleviated by cadmium-tolerant Pseudomonas aeruginosa under cadmium stress condition, the influences of bacterial strian on the root vigor and leaf physiological characteristics were analyzed under a set of hydroponic experiments involving adding bacteria suspension, empty carrier, microbial inoculum with 20 μmol·L为揭示耐镉铜绿假单胞菌缓解镉胁迫水稻的生理效应,以无镉处理为对照,通过添加菌液、空载体、菌剂及20 μmol·L

The realization of more energy efficient nanomagnetic information devices relies on the existence of magnetic insulators capable of supporting pure spin currents in the absence of a dissipative charge current. Currently, there is a limited number of thin-film magnetic insulators with low magnetic damping. Li0.5Fe2.5O4 (LFO) is well known to possess the lowest damping among the bulk spinel structure oxides, but, thus far, LFO thin films have not lived up to these expectations. Here, we demonstrate low magnetic damping (even lower than typical bulk values) and bulk magnetization in 3 nm thick epitaxial LFO thin films. At room temperature, SQUID magnetometry shows a high saturation magnetization of 320 kA/m, and broadband ferromagnetic resonance measurements yield an effective Gilbert damping parameter of 1.3 × 10 − 3, which is among the lowest reported for ferro-/ferrimagnetic films of comparable thickness. Our results show the promise of LFO as a candidate material for spin current-based spintronics.

We report our study of twin domains in $La_{2-x}Sr_x CuO_4$ under uniaxial pressure. Using bulk-sensitive x-ray microdiffraction in Laue geometry, we image the distribution of twin domains at room temperature. When compressive uniaxial pressure is applied along one of the in-plane crystallographic axes, the domain population changes dramatically. We observe that the twin domain with shorter lattice parameter along the direction of pressure is unstable under compression, and disappears completely with only moderate pressure. On the other hand, application of tensile pressure changes the domain structure only slightly, demonstrating the asymmetric response of the sample to uniaxial pressure. Our observations suggest that a crystal's response to uniaxial pressure is complex and could deviate easily from the linear-response regime., 5 pages, 4 figures, to appear in App. Phys. Lett

In this paper, some main factors such as soil type, land use pattern, lithology type, topography, road, and industry type that affect soil quality were used to precisely obtain the spatial distribution characteristics of regional soil quality, mutual information theory was adopted to select the main environmental factors, and decision tree algorithm See 5.0 was applied to predict the grade of regional soil quality. The main factors affecting regional soil quality were soil type, land use, lithology type, distance to town, distance to water area, altitude, distance to road, and distance to industrial land. The prediction accuracy of the decision tree model with the variables selected by mutual information was obviously higher than that of the model with all variables, and, for the former model, whether of decision tree or of decision rule, its prediction accuracy was all higher than 80%. Based on the continuous and categorical data, the method of mutual information theory integrated with decision tree could not only reduce the number of input parameters for decision tree algorithm, but also predict and assess regional soil quality effectively.

Taking topographic factors and NDVI as auxiliary variables, and by using regression-kriging method, the spatial variation pattern of soil fertility in Bashan tea garden in the hilly area of Fuyang City was explored. The spatial variability of the soil fertility was mainly attributed to the structural factors such as relative elevation and flat/vertical curvature. The lower the relative elevation, the worse the soil fertility was. The overall soil fertility level was relatively high, and the area with lower soil fertility only accounted for 5% of the total. By using regression-kriging method with relative elevation as auxiliary variable, the prediction accuracy of soil fertility was obviously higher than that by using ordinary kriging method, with the mean error and root mean square error being 0. 028 and 0. 108, respectively. It was suggested that the prediction method used in this paper could fully reflect the effects of environmental variables on soil fertility , improve the prediction accuracy about the spatial pattern of soil fertility, and provide scientific basis for the precise management of tea garden.

Biomarkers in breast neoplasms provide invaluable information regarding prognosis and help determining the optimal treatment. We have examined the possible correlation between cancer stem cell (CSC)-like markers (CD133, paired box gene 2 protein (PAX2), epithelial specific antigen (ESA)), and a new membrane estrogen receptor (G-protein coupled receptor 30 (GPR30)) in invasive ductal breast carcinomas with known clinicopathological parameters, tumor recurrence, and expression of some known biomarkers.In 74 invasive ductal breast carcinomas, we investigated the protein expression of these molecular markers by immunohistochemistry, and their associations with known clinicopathological parameters, tumor recurrence, and expression of some known biomarkers. We studied the interrelationship between the expressions of these proteins.CD133, a putative CSC marker, was positively related to tumor size, tumor stage, and lymph node metastasis. PAX2 was negatively correlated with tumor recurrence. ESA, one of the breast CSC markers, was an indicator of tumor recurrence. GPR30 was associated with hormone receptors. Despite the correlation between GPR30 and the nuclear estrogen receptor, the expression was dependent. Positive staining of GPR30 in tumors displayed a significant association with high C-erbB2 expression and a tendency for tumor recurrence. A positive relationship between GPR30 and CD133 existed.Detecting the expression of CD133, PAX2, ESA, and GPR30 in invasive ductal breast carcinomas may be of help in more accurately predicting the aggressive properties of breast cancer and determining the optimal treatment.

To evaluate the status of lymph node metastasis (LNM) and reasonable procedure in early gastric cancer (EGC).Two hundred and ninety-two patients with histologically proven mucosal or submucosal gastric cancer who underwent gastrectomy/lymphadenectomy were included in this study. The numbers of total dissected lymph node were all above 15 in all patients. The clinical characteristics, pathologic features, and LNM were assessed by univariate and multivariate analysis.LNM were observed in 43 of 292 cases (14.7%), and 6.4% in mucosal lesions and 22.4% in submucosal lesions. The LNM was identified in 12.7% at the first level, 7.2% at the second level and 0.34% at the third level. The LNM frequency was found in the 6, 3, 4, 1, 5 lymph node (from high to low) consequently at the first level and the 7, 8a lymph node at the second level. The EGC with nodal involvement and the tumors2.0 cm in diameter were all depressed type. The diameter of elevated type with LNM was no less than 3.0 cm in this series. The depth of invasion and lymphatic vessel involvement were independent influencing factors in LNM on multivariate analysis (P0.05).Less extensive surgery might be considered for the elevated type EGC, and tumorsor= 2.0 cm in diameter and mucosal lesions. Gastrectomy with D1 plus No.7, 8a lymphadenectomy might be carried out in the depressed type/or= 3.0 cm in diameter, or in the elevated type/3.0 cm in diameter. With respect to the depressed type EGC/tumors3.0 cm in diameter, gastrectomy with D2 lymphadenectomy is proper.

To investigate the expression of programmed cell death 4 (PDCD4) protein and its clinicopathological significance in human pancreatic cancer.Immunohistochemistry was used to examine the expression of PDCD4 protein in 69 specimens of pancreatic cancer and Western blot in 8 fresh specimens.The expression of PDCD4 protein was significantly lower in all 8 fresh pancreatic cancer tissues than that in non-cancerous tissues detected by Western blot. Compared with non-cancerous pancreatic tissue (80% of positive cells), low PDCD4 expression was shown in 69 pancreatic cancer tissues (30% of positive cells in 36 cases and 30%-80% of positive expression cells in 33 cases). In the 33 cases with 30% and 80% of positive expression cells, the expression rates of PDCD4 protein were 57.6%, 24.2%, and 18.2% in well, moderately, and poorly differentiated cancers, respectively. In the 36 cases less than 30% of positive expression cells, however, the expression rate of PDCD4 protein in well, moderately, and poorly differentiated cases were 19.4%, 41.7%, and 38.9%, respectively. 67.4% (15/23) of the moderately differentiated cases and 70% (14/20) of the poorly differentiated cases showed30% of positive expression cells. Only 26.9% (7/26) of the well differentiated cases, however, showed30% of positive expression cells, indicating that low PDCD4 expression was associated with histological grade (P0.01). There was no relationship between PDCD4 expression and other clinicopathological parameters including patients' sex, age, and TNM stage.Expression of PDCD4 protein is low in human pancreatic cancer and is correlated with the differentiation levels of human pancreatic cancer. PDCD4 may play an important role in the occurrence and development of pancreatic carcinomas.