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第一期相射血分数（EF1）是指从左室舒张末期至主动脉血流速度达到峰值的左室容积变化百分比，本文综述了EF1在早期检测主动脉瓣狭窄、稳定性冠状动脉疾病、新型冠状病毒肺炎等患者左室收缩功能障碍的研究进展，分析其在临床应用中的优势与局限性，并对其未来发展提出展望，即EF1作为一个反映早期左室收缩功能障碍的新指标，具备临床推广应用的可能。

质子交换膜 （proton exchange membrane，PEM）电解制氢运行灵活，具有优异的可再生能源波动适应性，是极具发展前景的绿色制氢技术。然而，在实际PEM电解制氢运行过程中，可能存在离子污染，对PEM电解堆的性能以及运行寿命产生很大影响。为此，首先分析了离子污染的来源，一方面来自水中的残余金属阳离子，如Na+、Ca2+、Mg2+等，另一方面来自电解堆内部关键材料和系统水循环管路因化学或电化学腐蚀产生的痕量金属离子，如Fe3+、Cu2+、Ni2+等；然后综述了不同离子污染对电解性能的影响，包括欧姆过电位、阴极反应过电位与阳极反应过电位；最后，综述了离子污染缓解策略，即如何避免规模化电解制氢过程中杂质离子污染带来的能效和成本问题。

目的】探讨异常子宫出血（AUB）的子宫内膜病理类型及其与患者的年龄、体质量指数、腰围、臀围和腰臀比等因素相关关系。【方法】收集2017年1月至6月在中山大学附属第三医院日间手术室因AUB进行诊断性刮宫或宫腔镜检查并子宫内膜活检的206名病人资料，包括年龄、身高、体质量、腰围、臀围、子宫内膜病理等，进行相关统计分析。【结果】①子宫内膜病理类型有增殖期或分泌期子宫内膜（NE），子宫内膜部分增殖、部分分泌改变（DPE），子宫内膜息肉（EP），子宫内膜增生改变和（或）增生过长（EHwithoutatypia），子宫内膜轻度、中度、重度不典型增生（EHwithatypia），和子宫内膜样腺癌（EC）。各类型占比分别为32.52%，8.25%，6.31%，40.77%，9.22%和2.91%。②EC组的年龄为50.0（S=7.3）岁，大于NE组的年龄42.0（S=13.0）岁，差异有统计学意义（P

【目的】采用多重置换扩增建立一种可靠、准确的植入前遗传学诊断方法，应用于X-连锁严重联合免疫缺陷病 （X-SCID）的植入前遗传学诊断（PGD）。【方法】选择5个位于致病基因IL-2受体γ链（IL2RG）基因两侧的短串联重复序列 （STR）位点对X-SCID家系进行单体型分析，采用多重置换扩增（MDA）对单细胞进行全基因组扩增，对扩增产物采用在家 系分析中具有多态性的STR位点进行单体型分析，结合位点Amel进行性别诊断，STR位点均采用单重荧光PCR，同时对 IL2RG基因exon5进行测序分析。【结果】对家系分析中，共有3个STR位点具有多态性。对10个单淋巴细胞及10个单卵裂 球进行了预实验：MDA扩增成功率为100%，对致病基因IL2RG exon5的行基因测序的检测效率为100%；对于3个有多态性 的STR位点和AMEL，PCR扩增效率为96.3%(77/80)，等位基因脱扣率（ADO）为11.5%(7/61)。对该家系进行了一个周期的 PGD，对7个胚胎进行了诊断，其中2个为正常胚胎，移植后获得双胎妊娠，早产活产一个健康男婴及一个健康女婴。【结 论】采用多重置换扩增结合致病基因特异性扩增测序检测及单体型分析在单细胞水平对X-连锁严重联合免疫缺陷病进行 检测，两者相结合可避免污染、等位基因脱扣等导致的误诊，提高了PGD诊断效率。

【目的】回顾性分析剖宫产瘢痕部位妊娠（CSP），3种不同治疗方案的疗效及其优缺点。【方法】2006年5月至 2016年9月期间中山大学附属第三医院及中山大学附属第一医院妇科确诊并治疗的CSP 186病例，根据其治疗方案，分为3 组：手术组（经阴道剖宫产瘢痕部位妊娠物切除+修补术，73例）、药物组（MTX+米非司酮+清宫术，51例）、栓塞组（双侧子宫 动脉栓塞后+清宫术，62例）。比较3组治疗方案的成功率、住院时间、住院费用及治疗副作用。【结果】3组治疗方案中成功 率分别为：98.6%、54.9%、80.6%；住院时间为（7.3 ± 3.3）、（16.2 ± 11.2）、（12.6 ± 10.4）d；住院费用为（7 966 ± 1 987）、（5 499 ± 1 965）及（15 863 ± 5 941）元；治疗副作用发生率为：15.1%、23.5%、37.1%；以上比较均有统计学差异（P < 0.05）。其中手术 组成功率最高，住院时间最短，费用较低，治疗副作用也最少，并且无严重的并发症出现。【结论】经阴道剖宫产瘢痕部位妊 娠物切除+修补术是治疗子宫部位瘢痕妊娠安全，有效的方法。

Copyright of Chinese Journal of Immunology is the property of Medical Periodical Society of Jilin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Accurate automatic segmentation of skin lesions is crucial to assist physicians in clinical diagnosis and treatment. Aiming at the problem that convolutional structure can extract local feature information but cannot model long-range dependencies, while Transformer can extract global context information but suffers from the loss of detail information, this paper proposed a parallel multi-scale automatic segmentation network PDTransCNN that integrated CNN and Transformer. Firstly, it constructed multi-level local correlation and captured long-range dependencies between contextual information by extracting the feature information of dermatological images in parallel with the CNN branch based on ResNet34 and Transformer branch. Secondly, it utilized the feature fusion module (FM) to complement the key information between the two branches of features and enhance the dependencies of the semantic information. Finally, it used the Transformer decoding unit to gradually fuse the semantic information extracted from the encoding block and the fusion unit in order to obtain the final segmentation result. The model was tested on ISIC2016, ISIC2017 and ISIC2018 datasets with Dice coefficients as high as 91.72%, 87.34% and 90.01%, and loU values of 85.60%, 79.55% and 83.67%, respectively. The experimental results show that PDTransCNN has better segmentation performance compared to other segmentation models and can segment skin lesion images clearly and effectively. [ABSTRACT FROM AUTHOR]

The dramatic increase in car ownership, contrasted with the inadequate development of urban parking infrastructure, has led to significant parking challenges. Such challenges, including limited parking spaces and restricted parking areas, severely hinder the efficacy of vehicular travel. Automated parking, distinguished by its low velocity and advanced autonomy in certain environments, emerges as the forefront product in the realm of autonomous driving. The development status and trend of automatic parking market at home and abroad were analyzed, and the planning and decision module of parking system was mainly discussed. The importance of motion planning was emphasized, which directly affects the quality of vehicle driving. The research results at home and abroad were reviewed, including curve interpolation, random sampling, graph search, intelligent algorithm and numerical optimization method. Furthermore, the advantages and limitations of different path planning were analyzed. In conclusion, the future integration and development direction of automatic parking technology were prospected. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southeast University / Dongnan Daxue Xuebao is the property of Journal of Southeast University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Uzhumqin sheep has the characteristics of large individual, abundant meat, and strong stress resistance. The mutton produced by Uzhumqin sheep is widely loved by consumers because of its delicious meat and rich nutrition. This paper analyzes the general situation of Uzhumqin sheep from two aspects: Forage characteristics and multi-vertebra characteristics of Uzhumqin sheep. In the aspect of meat quality characteristics, the influence mechanism is summarized in three parts: Dietary nutritional factors, muscle fiber characteristics and lipid. The mutual construction mechanism between intramuscular fat content, fatty acid types and oxidation degree of unsaturated fatty acids and nutritional value of Uzhumqin sheep is emphatically explored. Through the metabolic accumulation of flavor substances and volatile flavor compounds in Uzhumqin sheep, the specific reasons for the rich taste and no smell of mutton are explained. This paper systematically analyzes the causes of unique flavor and rich nutrition of Uzhumqin sheep, in order to provide reference for further research on the network of meat quality regulation mechanism. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Metal Working (1674-165X) is the property of Metal Working Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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The power Internet of Things(PIoT) is a smart service system that offers full-state awareness, efficient information processing, and convenient and flexible applications to users. However, these services also pose a risk of privacy leakage. The existing research on privacy protection of power data mainly concentrates on secure aggregation, but seldom addresses the core technology of many basic services, such as KNN query. Unlike traditional relational data, the PIoT collects flowing data of user electricity consumption, and the various power parameters exhibit dynamic correlations. Attackers can use data mining and other methods to infer future trends in data changes. Therefore, this paper proposed a privacy-preserving KNN query method. Firstly, it proposed a similarity measurement model based on bucket distance, and proved the upper and lower bounds of the error between the similarity measurement model based on bucket distance and the similarity measurement model based on Euclidean distance. Through this model, the similarity measurement could be transformed into set intersection operations. Then, it constructed a privacy-preserving function, which could generate different data privacy-preserving functions and query privacy-preserving functions for various smart terminals by substituting different parameters. Based on this, it proposed a data encoding scheme based on bucket partitioning and random number allocation. After being encrypted by the privacy-preserving function, the encoded data possessed the characteristic of ciphertext indistinguishability, and could effectively resist various attacks such as chosen plaintext attacks, data mining attacks, statistical analysis attacks, ICA attacks, and inference prediction attacks. Analysis and simulation demonstrate that the proposed secure KNN query method not only has high security but also has low overhead. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Quantitative analysis of the evolution of regional ecosystem service value(ESV)and spatial differentiation factors, and study on the characteristics of development of eco-economic harmony and consistency are helpful to promote the improvement of ecological functions of urban agglomerations and metropolitan areas. Taking Fuzhou metropolitan area as an example, based on remote sensing image data of 2001, 2010 and 2020, combined with GIS spatial visualization analysis, the optimized ESV assessment model, gravity center model, coefficient of variation, harmony index and consistency index, were adopted to measure the evolution of ESV of Fuzhou metropolitan area; secondly, its spatio-temporal harmony evolution characteristics with economic development were analyzed; finally, some suggestions on the eco-economy harmony development strategy of Fuzhou metropolitan area were provided. The results show that ① the whole ESV of Fuzhou metropolitan area decreases first and then increases from 2001 to 2020; thereinto, Fuzhou and Putian first decrease and then increase, while 4 counties of Ningde and 3 counties of Nanping continue to increase; ② the proportion of primary industry, annual average temperature and vegetation coverage rate have higher explanatory power for the spatial differentiation of ESV; limited by the original natural conditions, the spatial differentiation of ESV in Fuzhou metropolitan area is easily expanded by human interference; ③ the ecosystem service center of gravity of Fuzhou, Putian and 4 counties of Ningde has a trend of constantly moving away from the economic center of gravity, and the two are gradually separated; ④ there is no obvious conflict in the harmonious development of eco-economy in Fuzhou metropolitan area, but there are a large number of regions where the growth rate of ESV lags behind the GDP growth rate, and the economic development is under increasing ecological pressure. In the past 20 years, Fuzhou metropolitan area has formed a pattern of coexistence of economic agglomeration in Fuzhou, Putian and Ningde urban areas, and ecological agglomeration in 6 counties, the middle of Fuzhou metropolitan area. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the clinical diagnostic process, blood pressure is a crucial parameter that serves as a key reference for assessing blood flow dynamics and health status. Basing photo plethysmo graphy (PPG) for non-invasive continuous blood pressure monitoring has been a surge of interest in the research field, due to the limitations of traditional blood pressure measurements, such as invasiveness and intermittency. Firstly, theoretical background and technical principles of PPG were briefly introduced. Secondly, the specific processes including open datasets, evaluation standards, prepossessing methods, feature extraction, and model establishment, were comprehensively discussed, compared analysis of the advantages and disadvantages of different methods was also conducted. Finally, the challenges and future research directions in achieving non-invasive continuous blood pressure measurement based on PPG were summarized, with the aim of providing guidance for future research endeavors. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Modern Medicine & Health is the property of Journal of Modern Medicine & Health and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Modern Medicine & Health is the property of Journal of Modern Medicine & Health and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate the effect of 900 MHz mobile phone electromagnetic radiation on ultrastructure and marginal cells of cochlea in rats. Methods Forty adult SD rats were selected and exposed to 900 MHz mobile phone electromagnetic radiation for different time per day for a total of 28 days in order to establish the mobile phone electromagnetic radiation rat models. The rats were divided into the control group, radiation for 6 h group, radiation for 12 h group and radiation for 24 h group. After exposure to electromagnetic radiation, the auditory brainstem response, 40 Hz auditory event-related potential and auditory steady-state response threshold of rats were tested to evaluate the effect of electromagnetic radiation on auditory function of rats. The ultrastructure of cochlea was observed under scanning electron microscope and light microscope after hematoxylin-eosin staining. DNA damage in cochlear marginal cells was detected by comet assay. Flow cytometry was used to measure the effect of electromagnetic radiation on apoptosis of marginal cells and the level of reactive oxygen species. Results The response thresholds of each index of auditory function in rats after mobile phone electromagnetic radiation were all higher than those in the control group (P<0.05). With the increase of daily exposure time, the ultrastructure of rat cochlea showed varying degrees of abnormal arrangement and structure of outer hair cell cilia, morphological changes of organ of Corti and diapedesis of erythrocyte in cochlea. There was no significant difference in DNA damage or apoptosis rate of rat cochlear marginal cells among groups (P ＞ 0.05).The reactive oxygen species level in the radiation for 24 h group was higher than that in the control group (P ＜ 0.001), while there was no significant difference among the other groups and the control group (P ＞ 0.05). Conclusions Long-term mobile phone electromagnetic radiation can cause the ultrastructure damage of rat cochlea and decrease the auditory function, but it is not enough to cause the DNA damage and apoptosis of cochlear marginal cells. Longer radiation exposure can cause the increase of reactive oxygen species. [ABSTRACT FROM AUTHOR]

Copyright of Secretary (16742354) is the property of Secretary Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There is a significant correlation that the elevation of lipoprotein(a)[Lp(a)] levels is associated with the occurrence of cardiovascular disease(CVD), and this recognition has gradually gained attention. However, evidence on effective ways to lower Lp(a) and whether lowering Lp(a) levels improves cardiovascular disease risk remains insufficient, resulting in the importance of Lp(a) not being fully recognized yet. The latest clinical and genetic research progress reveal the key role of Lp(a) in the pathogenesis of CVD. Therefore, emerging therapeutic strategies, such as proprotein convertase bacillus subtilis protease-kexin type 9 inhibitors or antisense oligonucleotide technology, show some potential in lowering Lp(a). This article reviewed the research progress of Lp(a) and cardiovascular risk. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Taking Hainan Island as a case and using the panel data of population, economics and social infrastructure from national census and public reports of the 18 cities and counties, this paper examined the spatio-temporal dynamic characteristics and its influencing factors of registered population urbanization in 2000-2018 utilized the methods of spatial autocorrelation and multi-linear regression. The results shows that, firstly, the years 2004 and 2015 are both turning points for the urbanization of Hainan's registered population, which can be divided into three stages: 2000-2003, 2004-20014, and 2015-2018. In nearly 20 years, the urbanization level of the registered population in Hainan Island increases slowly and has achieved remarkable success, each stage shows different fluctuation features due to the changes of local policies and other influencing factors; Spatially, the agglomeration features are dominated by significant discrete distribution, and the distribution pattern and agglomeration types vary greatly; Migration preferred to place with higher payment, economy well-developed, better educational level, more employment opportunities. However, either industry structure or investment was not as effective as hoped, which reflected some problems behind the urbanization growth. For example, the in-migration in Hainan Island was mainly from rural areas, they usually cannot have the same rights as registered population. During the development of the free trade port, increasing the urbanization of registered population is significantly important for improving the urbanized quality. Therefore, it is essential to enhance the management of household registration, accelerate the ability of local urbanization in rural areas, and narrow the gap between urban and rural public services to ensure the residential living standards. [ABSTRACT FROM AUTHOR]

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In the research field of projectile penetration into reinforced concrete, the penetration depth discreteness generally exists in experiments and empirical formulas, and the difference of impact positions is one of the main reasons for this discreteness. To explore the penetration depth discreteness caused by the impact position difference and reveal its mechanism, the finite element models of 3 typical impact positions were established with reference to a published penetration test. The main reasons for the differences in the penetration processes of 3 typical impact positions were compared and analyzed. Based on the numerical calculation results, the expression characterizing the discreteness of penetration depth was summarized. The results show that, the penetration depth of the projectile impacting reinforced concrete is a range value. The expression was preliminarily verified. The main factors causing the penetration depth discreteness are the number of rebars hit by the projectile and the duration of contact with steel bars. This discreteness decreases with the ratio of the projectile diameter to the mesh size of rebars. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Resources & Environment / Nongye Ziyuan yu Huanjing Xuebao is the property of Journal of Agricultural Resources & Environment Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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