Synthetic analysis of meteorological elements for the sea fogs occurred in northwest the Yellow Sea under low pressure control and comparison with sea fogs occurred under high pressure control in summer

Based on the principle of transient perturbation analysis,in this paper,a method to objectively determine the weather pattern formed by sea fog is provided.On the basis of the classification results,the circulation situation,divergence and vertical velocity field,and the vertical profile of temperature and humidity are synthesized and analyzed.The basic characteristics of the circulation and physical field of sea fog under low pressure control(L type sea fog)are obtained,and the results are compared with the sea fog under the control of high pressure(H type sea fog):a)L type sea fogs potential height anomaly disturbance is mainly manifested in the low layer,and its average value is-65.66 gpm,gradually weakening upward;b)L type sea fogs inversion structure is weaker than H type sea fogs when it occurs,the fog layer is thicker and the high relative humidity level is high over the fog layer,while the H type sea fogs fog layer has a relatively obvious dry layer;c)L sea fog has three layers of structure at the vertical direction.The first layer 1000-950 hPa is convergence accompanied by weak rise and subsidence,the second layer 950-850 hPa is divergence accompanied by weak subsidence,and the third layer 850 to 500hPa is gradually strengthened.While there are two layer structures of the H type sea fog.1000 hPa is divergence accompanied by weak rising and sinking movement,950-500 hPa is a uniform subsidence movement.d)Probability density statistical analysis further quantified the vertical movement of L and H type sea fog and the distribution of relative humidity in each layer.These conclusions provide an important reference for forecasting the sea fog in the northwest of the Yellow Sea under the condition of low pressure circulation in summer.

High-dose vs low-dose proton pump inhibitors for upper gastrointestinal bleeding:A meta-analysis

AIM:To evaluate the efficacy of high-dose proton pump inhibitors(PPIs)vs low-dose PPIs for patients with upper gastrointestinal bleeding.METHODS:PubMed,Embase,the Cochrane Library,and Web of Science were searched to identify relevant randomized controlled trials(RCTs).Eligible trials were RCTs that compared high-dose PPI with low-dose PPI following endoscopic hemostasis.The primary endpoint was rebleeding;secondary endpoints were patient numbers that needed surgery,and mortality.The meta-analysis was performed with a fixed effects model or random effects model.RESULTS:Nine eligible RCTs including 1342 patients were retrieved.The results showed that high-dose intravenous PPI was not superior to low-dose intra-venous PPI in reducing rebleeding[odds ratio(OR)= 1.091,95%confidential interval(CI):0.777-1.532],need for surgery(OR=1.522,95%CI:0.643-3.605) and mortality(OR=1.022,95%CI:0.476-2.196).Subgroup analysis according to different region revealed no difference in rebleeding rate between Asian patients(OR=0.831,95%CI,0.467-1.480)and European patients(OR=1.263,95%CI:0.827-1.929).CONCLUSION:Low-dose intravenous PPI can achieve the same efficacy as high-dose PPI following endoscopic hemostasis.

Motivations Underlying the Snack Choices of Japanese Junior High School Students: A Study Based on Cluster Analysis

The aims of the present study were to group junior high school students according to factors influencing their snack choice and identify differences between the characteristics and snack choice behaviors of the groups. An anonymous self-report questionnaire was administered to 1936 students (13 - 15 years old) in eight junior high schools in Tokyo, Japan. The students responded to the Snack Choice Questionnaire (SCQ) as well as questions concerning snacking behaviors, lifestyles, and demographics. Cluster analysis was applied to sort the sample according to SCQ scores. Each cluster’s characteristics were examined by gender using the χ2 test or the Kruskal-Wallis test with a Bonferroni adjustment. Participants were divided into four groups: high in all factors, low in all factors, low value in health, and value in health. The “value in health” group was composed of more girls than boys and the “low in all factors” group had fewer girls than boys. Those in the “high in all factors” and “low value in health” groups indicated that they consumed more snacks. Moreover, gender differences were revealed. By assessing the SCQ prior to providing nutrition education, we can obtain valuable information to make nutrition education planning.

Tidal Analysis of High and Low Water Data

The harmonic analysis method based on high and low water levels is discussed in this paper. In order to make full use of the information of high and low water observations (the time derivative of water level at the observation time is zero), the weight coefficient, w, is introduced to control the importance of the part related to this information in the error formula. The major diurnal constituents, O 1 and K 1, and semi diurnal constituents, N 2, M 2 and S 2 are selected directly from the monthly data analysis, and some other important constituents, P 1, ν 2 and K 2, are included as the inferred constituents. The obtained harmonic constants of the major constituents are very close to those obtained from the analysis of hourly data, and this shows that high and low water data can be used to extract tidal constants with high accuracy. The analysis result also shows that the inference and the weighting coefficient are important in the high and low water data analysis, and it is suggested that w ≥1 should be taken in monthly high and low water data analysis. This analysis method can be used directly to analyze altimetric data with w =0.

Advances in microfluidic-based DNA methylation analysis

DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation studies to both clinical medicine and scientific research.Microflu-idic chips are excellent carriers for molecular analysis,and their use can provide improvements from multiple aspects.On-chip molecular analysis has received extensive attention owing to its advantages of portability,high throughput,low cost,and high efficiency.In recent years,the use of novel microfluidic chips for DNA methylation analysis has been widely reported and has shown obvious superiority to conventional methods.In this review,wefirst focus on DNA methylation and its applications.Then,we discuss advanced microfluidic-based methods for DNA methylation analysis and describe the great progress that has been made in recent years.Finally,we summarize the advantages that microfluidic technology brings to DNA methylation analysis and describe several challenges and perspectives for on-chip DNA methylation analysis.This review should help researchers improve their understanding and make progress in developing microfluidic-based methods for DNA methylation analysis.

Methanol Distillation System: Process Analysis and Column Design

Base on industrial research and experience, the process of methanol distillation is analyzed,and above all, a new concept of high pressure flowsheet and low pressure flowsheet is defined. The new configuration helps to handle problems encountered in many factories in China. The inter influence between process and column internal pattern is also pointed out. Recommendation of new column internal designs is given. Finally, industrial examples tell the how the new concept works and the possibility of combining process to give more opens to solve engineering problems.

Comparison of Different Cartridges of Solid Phase Extraction for Determination of Polyphenols in Tobacco by UPLC/MS/MS and Multivariate Analysis

The comparison of solid phase extraction（SPE） for the preconcentration and isolation of polyphenols in tobacco samples was carried out by ultra-high performance liquid chromatography/tandem mass spectrometry （UPLC/MS/MS） and multivariate analysis.Several adsorbing materials of SPE（C18,NH2,SAX and OASIS） were investigated.It was found that the C18 and OASIS cartridges can not only speed up the purification process,but also simplify the SPE operation.A UPLC/MS/MS was used for the determination of polyphenols in tobacco samples after purification.All analytes were separated and determined in 2min.The limit of detection was 0.05 ng/mL.Cluster analysis（CA） and principal component analysis（PCA） were used for the analysis of 4 varieties（flue-cured tobacco,oriental tobacco,sun-cured tobacco and burley） in order to interpret the effect of planting and machining process on the concentration of polyphenols.The different types of tobacco samples could be easily clustered by CA.PCA on the chemical composition of tobacco resulted in two principal components（PCs） that take 84.2% of the total variance.The PCA and CA indicate that the polyphenols can be used for distinguishing tobacco types.

Performance Modeling and Approximate Analysis of Multiserver Multiqueue Systems with Poisson and Self-similar Arrivals

The problem of state space explosion is still ran outstanding challenge in Markovian performance analysis for multiserver multiqueue (MSMQ) systems. The system behavior of a MSMQ system is described using stochastic high-level Petri net (SHLPN) models, and an approximate performance analysis technique is proposed based on decomposition and refinement methods as well as iteration technique. A real MSMQ system, Web-server cluster, is investigated. The performance of an integrated scheme of request dispatching and scheduling is analyzed with both Poisson and self-similar request arrivals. The study shows that the approximate analysis technique significantly reduces the complexity of the model solution and is also efficient for accuracy of numerical results.

Automated Dynamic Cellular Analysis in Time-Lapse Microscopy

Analysis of cellular behavior is significant for studying cell cycle and detecting anti-cancer drugs. It is a very difficult task for image processing to isolate individual cells in confocal microscopic images of non-stained live cell cultures. Because these images do not have adequate textural variations. Manual cell segmentation requires massive labor and is a time consuming process. This paper describes an automated cell segmentation method for localizing the cells of Chinese hamster ovary cell culture. Several kinds of high-dimensional feature descriptors, K-means clustering method and Chan-Vese model-based level set are used to extract the cellular regions. The region extracted are used to classify phases in cell cycle. The segmentation results were experimentally assessed. As a result, the proposed method proved to be significant for cell isolation. In the evaluation experiments, we constructed a database of Chinese Hamster Ovary Cell’s microscopic images which includes various photographing environments under the guidance of a biologist.

A Low-Memory-Requiring and Fast Approach to Cluster Large-Scale Decoy Protein Structures

This work demonstrates the so-called PCAC (Protein principal Component Analysis Clustering) method, which clusters large-scale decoy protein structures in protein structure prediction based on principal component analysis (PCA), is an ultra-fast and low-memory-requiring clustering method. It can be two orders of magnitude faster than the commonlyused pairwise rmsd-clustering (pRMSD) when enormous of decoys are involved. Instead of N(N – 1)/2 least-square fitting of rmsd calculations and N2 memory units to store the pairwise rmsd values in pRMSD, PCAC only requires N rmsd calculations and N × P memory storage, where N is the number of structures to be clustered and P is the number of preserved eigenvectors. Furthermore, PCAC based on the covariance Cartesian matrix generates essentially the identical result as that from the reference rmsd-clustering (rRMSD). From a test of 41 protein decoy sets, when the eigenvectors that contribute a total of 90% eigenvalues are preserved, PCAC method reproduces the results of near-native selections from rRMSD.

Is Escalated Radiation Dose in Definitive Chemoradiotherapy Better for Inoperable Esophageal Carcinoma? A Meta-Analysis and Systematic Review

Purpose: This study aimed to compare the survival benefits between different total radiation doses in definitive chemoradiotherapy (dCRT) for inoperable esophageal carcinoma (EC) based on modern radiotherapy techniques. Methods: A systematic review was performed by searching the databases of PubMed, EMBASE, Cochrane Central Register of Controlled Trials and Web of Science. All studies published prior to November 30, 2022, comparing radiation dose and disease-related outcomes in EC patients. The hazard ratio (HR) and odds ratio (OR) were used to describe the risk of outcomes and toxicities. Results: Seven prospective trials involving 1124EC patients were enrolled for analyses. The results revealed that the effect on overall survival (HR = 0.99, 95% CI = 0.85 - 1.16, P = 0.94), local progression-free survival (HR = 0.83, 95% CI = 0.58 - 1.17, P = 0.29), local regional progression-free survival (HR = 0.94, 95% CI = 0.76 - 1.17, P = 0.61), progression-free survival (HR = 0.90, 95% CI = 0.71 - 1.13, P = 0.35) was similar in the high-dose and standard-dose groups. Additionally, a high radiation dose exhibited a potential disadvantage in respiratory toxicities when compared with a standard dose (4.8% vs 2.2%, OR 2.11, P = 0.06). Conclusions: The efficacy of the HD group (≥60 Gy) and the SD group (approximately 50 Gy) for inoperable local advanced EC was similar. However, the HD group exhibited a high radiation dose exhibited a potential disadvantage in respiratory toxicities when compared with a standard dose. Simultaneously, the final results of several ongoing prospective trials regarding the optimal radiation dose in dCRT are awaited.

The Superconductivity in Fe-Based Family of Superconductors and Its Electronic Structure Analysis in Presence of Dopants Rh and Pd

The discovered in 2008 Fe-based superconductors (SC) are a paramagnetic semimetal at ambient temperature and in some cases they become superconductor upon doping. In spite of so many years since its discovery it is still not known the mechanism that leads to superconductivity. The electronic structure study is used for determining key features of the SC mechanism in these materials. The calculations were performed using the modern suite of programs MOLPRO 2021. We performed quantum calculations of a cluster embedded in a background charge distribution that represents the infinite crystal. The Natural Population Analysis was used for determining the charge and spin distribution in the studied materials. As follows from our results, the possible mechanism for superconductivity corresponds to the RVB theory proposed by Anderson for high Tc superconductivity in cuprates.

An Analysis of Two-Dimensional Image Data Using a Grouping Estimator

Machine learning methods, one type of methods used in artificial intelligence, are now widely used to analyze two-dimensional (2D) images in various fields. In these analyses, estimating the boundary between two regions is basic but important. If the model contains stochastic factors such as random observation errors, determining the boundary is not easy. When the probability distributions are mis-specified, ordinal methods such as probit and logit maximum likelihood estimators (MLE) have large biases. The grouping estimator is a semiparametric estimator based on the grouping of data that does not require specific probability distributions. For 2D images, the grouping is simple. Monte Carlo experiments show that the grouping estimator clearly improves the probit MLE in many cases. The grouping estimator essentially makes the resolution density lower, and the present findings imply that methods using low-resolution image analyses might not be the proper ones in high-density image analyses. It is necessary to combine and compare the results of high- and low-resolution image analyses. The grouping estimator may provide theoretical justifications for such analysis.

Progressive Failure Analysis of Quasi-isotropic Self-reinforced Polyethylene Composites by Comparing Unsupervised and Supervised Classifications of Acoustic Emission Data

Unsupervised and supervised pattern recognition( PR)techniques are used to classify the acoustic emission( AE) data originating from the quasi-isotropic self-reinforced polyethylene composites,in order to identify the various mechanisms in the multiangle-ply thermoplastic composites. Ultra-high molecular weight polyethylene / low density polyethylene( UHMWPE / LDPE)composites were made and tested under quasi-static tensile load. The failure process was monitored by the AE technique. The collected AE signals were classified by unsupervised and supervised PR techniques, respectively. AE signals were clustered with unsupervised PR scheme automatically and mathematically. While in the supervised PR scheme,the labeled AE data from simple lay-up UHMWPE / LDPE laminates were utilized as the reference data.Comparison was drawn according to the analytical results. Fracture surfaces of the UHMWPE / LDPE specimens were observed by a scanning electron microscope( SEM) for some physical support. By combining both classification results with the observation results,correlations were established between the AE signal classes and their originating damage modes. The comparison between the two classifying schemes showed a good agreement in the main damage modes and their failure process. It indicates both PR techniques are powerful for the complicated thermoplastic composites. Supervised PR scheme can lead to a more precise classification in that a suitable reference data set is input.

Detecting Factor Ⅺ Deficiency in Holstein Cattle Using PCR Analysis

[Objective] This study established a method to detect Factor Ⅺ by polymerase chain reaction analysis.[Method]A pair of primers was designed and synthesized according to sequences of FⅪ gene in Holstein calves,published in Genbank. Polymerase chain reaction was used to analyze FⅪ deficiency of 576 Holstein calves in Henan,and the result was verified by DNA sequencing. [Result] We detect 576 cows,which include two carriers and one F Ⅺ deficiency,and the result was consistent with the DNA sequencing. The frequency of the FⅪ mutant allele was 0.3%,the carrier was 0.3%,the prevalence was 0.2%.[Conclusion]A method detecting FⅪ by polymerase chain reaction analysis was established. This method is not only simple and convenient,but also has a high accuracy and low cost,which is more suitable for large-scale FⅪ investigation.

基于Moldflow的高光无痕电视前壳注射模具设计

以液晶电视机前壳为例,结合制品的精度要求和模具结构特点,详尽分析高光无痕注塑模具流道系统、温度控制系统和复杂抽芯机构的设计方法,给出整套模具其它结构的设计要点。利用Moldflow软件,采用变模温工艺技术,对高光无痕注射成型工艺进行模拟分析,验证了流道系统和温度控制系统的控制效果。

通肠清胰合剂HPLC指纹图谱建立及多指标成分的含量测定

目的建立通肠清胰合剂的HPLC指纹图谱,并对5种成分进行含量测定。方法采用Agilent ZORBAX SB?C_(18)色谱柱(250 mm×4.6 mm,5μm),以乙腈?p H 5.0磷酸盐缓冲液为流动相,梯度洗脱,检测波长为230 nm和250 nm,流速为1.0 m L/min,柱温为30℃,进样量为10μL。通过中药色谱指纹图谱相似度评价系统(2012版)建立10个批次的通肠清胰合剂HPLC指纹图谱,同时进行相似度评价。结合软件SPSS 27.0、Origin Pro 2024b进行聚类分析和主成分分析。结果黄芩苷、芍药苷、大黄酸、厚朴酚、和厚朴酚分别在一定浓度范围内线性关系良好(r≥0.9998),平均回收率和RSD分别在96.39%~97.96%、1.54%~2.37%(n=6)之间。10批通肠清胰合剂指纹图谱显示存在12个共有峰,相似度为0.984~1.000。10批样品可聚为3类,其中S1~S7为第一类,S10为第二类,S8和S9为第三类。指认了5个成分,分别为大黄酸、芍药苷、黄芩苷、厚朴酚、和厚朴酚。结论本研究所建立的通肠清胰合剂HPLC指纹图谱及成分含量测定方法准确可靠、重复性强,为通肠清胰合剂的质量控制提供了科学依据。

四川凉山州西南低涡型暖区暴雨的统计特征

利用凉山州近10年4—10月的降水资料、常规地面观测、高空观测、ERA5再分析资料和FY-2G卫星TBB资料,对四川省凉山州西南低涡型区域性暖区暴雨进行统计分析和天气学分析。结果表明:(1)凉山州西南低涡型暖区暴雨的发生频率在年际变化上呈波动趋势,2016年和2022年发生频率最高,2017年最低;暴雨主要发生在夏季(6—8月),其中7月发生的频率最高;暴雨具有短时强降水特征,强降水常出现在傍晚到夜间,白天降水强度减弱。(2)暴雨发生在高能高湿的不稳定层结中,其水汽主要来源于孟加拉湾。(3)影响凉山州的西南低涡主要生成于川西高原南部到凉山州西北部,少数生成于四川盆地西南部到凉山州西北部,极少数生成于攀西地区西南部,故川西高原南部是凉山州西南低涡型暖区暴雨对流云团的主要发源地。(4)西南低涡暴雨对流云团常由块状和带状混合影响,影响范围广;暴雨区常出现在低涡中心或外围东南侧,降水成片集中。

基于指纹图谱结合化学模式识别的精天颗粒质量评价

目的 建立精天颗粒的超高效液相色谱(UPLC)指纹图谱,并结合化学模式识别法评价其质量。方法 以Luna~?Omega Polar C18(150 mm×2.1 mm,1.6μm)为色谱柱,以乙腈-0.2%磷酸溶液为流动相进行梯度洗脱,流速为0.2 mL/min,柱温为30℃,检测波长为265 nm。以16号峰为参照峰,通过《中药色谱指纹图谱相似度评价系统(2012版)》建立精天颗粒的UPLC指纹图谱,指认共有峰并进行相似度评价,同时确认每个共有峰的饮片归属。运用化学模式识别方法中的层次聚类分析(HCA)、主成分分析(PCA)对13批样品(S1~S13)进行分类,并采用正交偏最小二乘-判别分析(OPLS-DA)来识别导致不同批次样品间差异的关键性成分。结果 所建UPLC方法精密度、重复性、稳定性的RSD均不大于4.4%。在13批精天颗粒指纹图谱中共标定出25个共有峰;通过与对照指纹图谱比对,指认了其中10个共有峰,分别为3号峰(5-羟甲基糠醛)、5号峰(红景天苷)、8号峰(绿原酸)、15号峰(肉桂酸)、19号峰(芦荟大黄素)、20号峰(甘草酸铵)、21号峰(大黄酸)、23号峰(大黄素)、24号峰(甘草次酸)、25号峰(大黄酚)。13批样品指纹图谱的相似度为0.955~0.996。HCA结果显示,13批样品可聚为3类,其中S1、S5、S7、S11~S13为一类,S4、S6为一类,S2、S3、S8~S10为一类。PCA结果显示,主成分1~7的累计方差贡献率为92.666%。OPLS-DA进一步确定了13个差异性成分,这些成分主要来源于酒黄精、红景天、熟大黄和炙甘草等。结论 所建立的精天颗粒UPLC指纹图谱方法简便、稳定、重复性良好,结合化学模式识别方法能有效揭示精天颗粒不同批次间的整体质量差异。方中酒黄精、红景天、熟大黄、穿山龙、猪苓、桂枝、炙甘草的质量是影响精天颗粒整体质量的关键。