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Biologically inspired model of path integration based on head direction cells and grid cells

Yang ZHOU,De-wei WU

《信息与电子工程前沿（英文）》 2016年第17卷第5期页码 435-448 doi: 10.1631/FITEE.1500364

摘要： Some neurons in the brain of freely moving rodents show special firing pattern. The firing of head direction cells (HDCs) and grid cells (GCs) is related to the moving direction and distance, respectively. Thus, it is considered that these cells play an important role in the rodents’ path integration. To provide a bionic approach for the vehicle to achieve path integration, we present a biologically inspired model of path integration based on the firing characteristics of HDCs and GCs. The detailed implementation process of this model is discussed. Besides, the proposed model is realized by simulation, and the path integration performance is analyzed under different conditions. Simulations validate that the proposed model is effective and stable.

关键词： Head direction cells (HDCs) Grid cells (GCs) Path integration Bionic navigation

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Expression pattern and regulation of head-to-head genes

Xinxing CUI,Chunhong YANG,Li KANG,Guiyu ZHU,Qingqing WEI,Yunliang JIANG

《农业科学与工程前沿（英文）》 2014年第1卷第2期页码 130-136 doi: 10.15302/J-FASE-2014013

摘要： Vacuolar protein sorting 36 (VPS36), a protein primarily known for its role in the Endosomal Sorting Complex Required for Transport pathway, has recently been shown to be linked to chicken reproduction. Previous research showed that is significantly downregulated in sexually mature chicken ovaries compared to immature ones. In this study, using real-time quantitative RT-PCR, we investigated the expression pattern of and its head-to-head gene mRNA in chicken follicles. Small white follicles were found to have significantly higher expression of and mRNA than any other sized follicles ( <0.05). The expression of and mRNA were detected in both granulosa and theca layers of pre-ovulatory follicles, the expression of in theca layers was slightly higher than in granulosa cells. Treatment of small yellow follicles with follicle-stimulating hormone and estradiol resulted in a marked decrease of both and mRNA ( <0.05); however, progesterone, transforming growth factor-β 1 and luteinizing hormone induced no significant changes in and mRNA expression in these follicles. These results indicate that the head-to-head genes of and exhibit similar expression in chicken follicles and are involved in chicken follicle development.

关键词： chicken Vps36 Ckap2 mRNA follicle

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Basic consideration of research strategies for head and neck cancer

null

《医学前沿（英文）》 2012年第6卷第4期页码 339-353 doi: 10.1007/s11684-012-0213-7

摘要：

Head and neck cancer (HNC) consists of a group of malignancies affecting closely related anatomical regions of the upper aerodigestive tract (UADT), including the oral cavity, salivary glands, upper and lower jaw bones and facial skin; the nasal cavity, paranasal sinuses, pharynx, larynx and thyroid gland (although the latter is often excluded and considered as part of endocrine neoplasms). Of these, 90% of HNCs are histologically squamous cell carcinomas originating from the mucosal lining. These malignancies are strongly associated with certain environmental and life-style risk factors, principally tobacco in both smoked and smokeless forms, excessive alcohol consumption, diets poor in antioxidants and essential micronutrients, UV light, chemicals used in certain workplaces, and viruses, principally certain strains of human papillomavirus (HPV) and Epstein-Barr virus (EBV). These cancers are frequently aggressive in their biological behaviour with local invasion and metastasis to lymph nodes in the neck. Since most patients are already at late stages of disease at the time of diagnosis, the desirable practice of early diagnosis (first sign of the malignant lesion at an initial stage ) and early treatment, a critical priority to save lives and retain quality of life, is difficult to implement. Thus, primary prevention has been set as a key goal. This article aims to reinforce the basic knowledge of aetiology, key risk factors related to the development of head and neck cancer, basic features of clinical appearance of this group of cancers, and strategies for prevention and early detection. We also suggest basic research strategies on the basis of current knowledge, which should ultimately lead to the improvement of clinical management.

关键词： clinical management head and neck cancer prevention and early detection research strategies risk factors

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Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

《结构与土木工程前沿（英文）》页码 1163-1187 doi: 10.1007/s11709-023-0987-5

摘要： In this study, the concrete cone capacity, concrete cone angle, and load–displacement response of cast-in headed anchors in geopolymer concrete are explored using numerical analyses. The concrete damaged plasticity (CDP) model in ABAQUS is used to simulate the behavior of concrete substrates. The tensile behavior of anchors in geopolymer concrete is compared with that in normal concrete as well as that predicted by the linear fracture mechanics (LFM) and concrete capacity design (CCD) models. The results show that the capacity of the anchors in geopolymer concrete is 30%–40% lower than that in normal concrete. The results also indicate that the CCD model overestimates the capacity of the anchors in geopolymer concrete, whereas the LFM model provides a much more conservative prediction. The extent of the difference between the predictions by the numerical analysis and those of the above prediction models depends on the effective embedment depth of the anchor and the anchor head size. The influence of concrete surface cracking on the capacity of the anchor is shown to depend on the location of the crack and the effective embedment depth. The influence of the anchor head profile on the tensile capacity of the anchors is found to be insignificant.

关键词： cast-in anchor concrete cone capacity geopolymer concrete head size surface crack anchor profile

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factors for ventilator-associated pneumonia among patients undergoing major oncological surgery for head

null

《医学前沿（英文）》 2017年第11卷第2期页码 239-246 doi: 10.1007/s11684-017-0509-8

摘要：

Patients undergoing major oncological surgery for head and neck cancer (SHNC) have a particularly high risk of nosocomial infections. We aimed to identify risk factors for ventilator-associated pneumonia (VAP) in patients undergoing SHNC. The study included 465 patients who underwent SHNC between June 2011 and June 2014. The rate of VAP, risk factors for VAP, and biological aspects of VAP were retrospectively evaluated. The incidence of VAP was 19.6% (n=95) in patients who required more than 48 h of mechanical ventilation. Staphylococcus (37.7%), Enterobacteriaceae (32.1%), Pseudomonas(20.8%), and Haemophilus (16.9%) were the major bacterial species that caused VAP. The independent risk factors for VAP were advanced age, current smoking status, chronic obstructive pulmonary disease, and a higher simplified acute physiology score system II upon admission. Tracheostomy was an independent protective factor for VAP. The median length of stay in the ICU for patients who did or did not develop VAP was 8.0 and 6.5 days, respectively (P=0.006). Mortality among patients who did or did not develop VAP was 16.8% and 8.4%, respectively (P<0.001). The potential economic impact of VAP was high because of the significantly extended duration of ventilation. A predictive regression model was developed with a sensitivity of 95.3% and a specificity of 69.4%. VAP is common in patients who are undergoing SHNC and who require more than 48 h of mechanical ventilation. Therefore, innovative preventive measures should be developed and applied in this high-risk population.

关键词： ventilator-associated pneumonia (VAP) pneumonia risk factors surgery for head and neck cancer (SHNC)

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Model test study for ice force on the bank-head of the lead-navigating bank

SONG An, SUN Jinliang, LU Hai, WANG Yi′an

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 222-228 doi: 10.1007/s11709-007-0027-x

摘要： To determine the bank-head s ice force of the lead-navigating bank at key position that faces the ice directly of certain water conservancy, ice model test in reduced scale is designed and carried out based on the local situation on the spot and data observed. Preliminary conclusions are got through the analysis of the experimental data such as effect of the ice velocity on the ice force , ratio of components of forces when ice sheet acting on the vertical bank-head, ice force ratio of vertical to 45? incline as well as ratio of level ice force to the vertical ice force when acting on 45? incline. Finally, suggestions on determination of the ice force using formula are given after comparison between the result calculated by the present formula of ice force and the experimental results.

关键词： comparison lead-navigating bank vertical bank-head certain Preliminary

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Ultramicrostructure and clinical implications of satellite foci in front of the head of pterygium

LIU Haixia, XIANG Nan, ZHOU Xiongwu, HU Weikun, LI Guigang, ZHANG Hong

《医学前沿（英文）》 2007年第1卷第2期页码 211-214 doi: 10.1007/s11684-007-0040-4

摘要： In our previous studies, grey satellite foci were found in the front of heads of pterygia. This research was designed to investigate the ultramicrostructure and clinical implications of these satellite foci. The satellite foci were observed and counted under slit lamp biomicroscope. The patients with eye pterygia were divided into groups in terms of occupation, sex, age, length of history, grade of congestion, and size of the heads. The SPSS 13.0 software was used for statistical analysis. The cap areas and satellite foci were ultramicrostructurally examined. Among the total 62 eyes with pterygium, satellite foci were found in 34. The overall incidence of satellite foci was 54.8%. There were no significant differences in incidence among the subjects of different sex, age, and length of history. There were significant differences in incidence among the patients of different occupation, grades of congestion, and size of heads. Higher grades of congestion, outdoor occupations and larger pterygium heads were associated with higher incidence of satellite foci. High grades of congestion and bigger heads were also correlated with the number of satellite foci. Length of history bore no correlation with number of satellite foci. Histologically, the components of the cap areas and the foci were identical, with both consisting of mass of active fibroblasts. The activated fibroblasts existed in the natural tissue planes between Bowman s layer and basal cell layer. The fibroblasts in the satellite foci and the cap areas of a pterygium show some features of tumor cells and may play a vital role in the development and progression of a pterygium. The presence and amount of satellite foci around a pterygium can be used as an indicator for the speed of its growth.

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Qualitative analysis of direction of public hospital reforms in China

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《医学前沿（英文）》 2018年第12卷第2期页码 218-223 doi: 10.1007/s11684-017-0534-7

摘要：

Reforms in public hospitals are among the most important improvements in China’s health care system over the last two decades. However, the reforms that should be implemented in public hospitals are unclear. Thus, a feasible direction of reforms in Chinese public hospitals is suggested and reliable policy suggestions are provided for the government to reform public hospitals. The data used in this study were mainly derived from a qualitative study. Focus group discussions and in-depth interviews were conducted in Shanghai, Guangdong, and Gansu between May and December 2014. Government funding accounted for approximately eight percent of the total annual revenue of public hospitals in China, and the insufficient government subsidy considerably affects the operation mechanism of public hospitals. However, solely increasing this subsidy cannot address the inappropriate incentives of public hospitals in China. The most crucial step in setting the direction of reforms in public hospitals in China is transforming inappropriate incentives by implementing a new evaluation index system for directors and physicians in public hospitals.

关键词： public hospital government hospital public funding operation mechanism

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前往火星的三个太空任务

Mitch Leslie

《工程（英文）》 2020年第6卷第12期页码 1336-1338 doi: 10.1016/j.eng.2020.10.007

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基因组测序成本将再次降低

Robert Pollie

《工程（英文）》 2023年第23卷第4期页码 3-6 doi: 10.1016/j.eng.2023.02.002

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高速线材吐丝机吐丝管空间曲线研究和改进

刘宏民,姚双吉,杨利坡,庞志峰,李双来,刘武斌,闫胜友,褚建东

《中国工程科学》 2006年第8卷第11期页码 80-85

摘要：

针对唐钢高线吐丝机存在的吐丝质量问题，采用三次样条拟合现场实测数据得到吐丝管曲线方程；根据吐丝管中线材的速度和受力模型，分析线材在吐丝管中的运动状态，研究吐丝管空间曲线对吐丝质量的影响，得到吐丝管空间曲率波动过大和出口速度变化过快是导致吐丝质量不好的主要原因；通过改善吐丝管空间曲线和规范煨管工艺制度，显著改善了甩尾、吐圈摆动等吐丝质量，吐丝管寿命提高了1倍。

关键词：高速吐丝机吐丝管空间曲线

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微水头资源开发与发电装置研究现状及趋势

张玉全,郑源,孙科,杨春霞,罗红英

《中国工程科学》 2018年第20卷第3期页码 90-95 doi: 10.15302/J-SSCAE-2018.03.013

摘要：

我国水能资源丰富，开发水力发电技术是增加可再生能源供应、优化能源结构、缓解环境问题的优先选择。本文着眼于我国丰富的微水头资源，梳理河流、运河、水库、电厂尾水、管道供水、城市废水、海洋新能源等微水头资源需求和应用特点，总结适合开阔流域和封闭流域特点的两型微水头水力发电水轮机，对形成动势能结合型微水头水轮机设计方法和研究其流动特征和机理提供基础。介绍了微水头资源评估和水力发电水轮机研究的趋势，并对今后研究方向提出了建议。

关键词：微水头资源水力发电水轮机开阔流域封闭流域

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盾构隧道长距离独头掘进的控制测量技术

许维青,韩福忠

《中国工程科学》 2010年第12卷第12期页码 56-58

摘要：

北京地下直径线盾构独头掘进距离达5.2 km，因此隧道贯通精度控制难度大。通过测量精度分析，单纯通过导线测量已不能满足设计规定的贯通限差要求，施工中通过导线直接传递定向、洞内加测陀螺边、地上地下控制网紧密联系等辅助方法，提高了贯通横向误差的精度，达到了预期效果。

关键词：盾构长距离独头掘进控制测量

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Porcine pluripotent stem cells: progress, challenges and prospects

Jianyong HAN, Yi-Liang MIAO, Jinlian HUA, Yan LI, Xue ZHANG, Jilong ZHOU, Na LI, Ying ZHANG, Jinying ZHANG, Zhonghua LIU

《农业科学与工程前沿（英文）》 2019年第6卷第1期页码 8-27 doi: 10.15302/J-FASE-2018233

摘要：

Pluripotent stem cells (PSCs) are characterized by their capacity for high self-renewal and multiple differentiation potential and include embryonic stem cells, embryonic germ cells and induced PSCs. PSCs provide a very suitable model for the studies of human diseases, drugs screening, regenerative medicine and developmental biology research. Pigs are considered as an ideal model for preclinical development of human xenotransplantation, therapeutic approaches and regenerative medicine because of their size and physiological similarity to humans. However, lack of knowledge about the derivation, characterization and pluripotency mechanisms of porcine PSCs hinders progress in these biotechnologies. In this review, we discuss the latest progress on porcine PSCs generation, evaluation criteria for pluripotency, the scientific and technical questions arising from these studies. We also introduce our perspectives on porcine PSC research, in the hope of providing new ideas for generating naive porcine PSCs and animal breeding.

关键词： embryonic germ cells embryonic stem cells induced pluripotent stem cells pigs pluripotent stem cells

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Determination of telomerase activity in stem cells and non-stem cells of breast cancer

LI Zhi, HE Yanli, ZHANG Jiahua, ZHANG Jinghui, HUANG Tao

《医学前沿（英文）》 2007年第1卷第3期页码 294-298 doi: 10.1007/s11684-007-0056-9

摘要： Although all normal tissue cells, including stem cells, are genetically homologous, variation in gene expression patterns has already determined the distinct roles for individual cells in the physiological process due to the occurrence of epigenetic modification. This is of special importance for the existence of tissue stem cells because they are exclusively immortal within the body, capable of selfreplicating and differentiating by which tissues renew and repair itself and the total tissue cell population maintains a steady-state. Impairment of tissue stem cells is usually accompanied by a reduction in cell number, slows down the repair process and causes hypofunction. For instance, chemotherapy usually leads to depression of bone marrow and hair loss. Cellular aging is closely associated with the continuous erosion of the telomere while activation of telomerase repairs and maintains telomeres, thus slowing the aging process and prolonging cell life. In normal adults, telomerase activation mainly presents in tissue stem cells and progenitor cells giving them unlimited growth potential. Despite the extensive demonstration of telomerase activation in malignancy (>80%), scientists found that heterogeneity also exists among the tumor cells and only minorities of cells, designated as cancer stem cells, undergo processes analogous to the self-renewal and differentiation of normal stem cells while the rest have limited lifespans. In this study, telomerase activity was measured and compared in breast cancer stem cells and non-stem cells that were phenotypically sorted by examining surface marker expression. The results indicated that cancer stem cells show a higher level of enzyme activity than non-stem cells. In addition, associated with the repair of cancer tissue (or relapse) after chemotherapy, telomerase activity in stem cells was markedly increased.

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标题作者时间类型操作

Biologically inspired model of path integration based on head direction cells and grid cells

Yang ZHOU,De-wei WU

期刊论文

Expression pattern and regulation of head-to-head genes

Xinxing CUI,Chunhong YANG,Li KANG,Guiyu ZHU,Qingqing WEI,Yunliang JIANG

期刊论文

Basic consideration of research strategies for head and neck cancer

null

期刊论文

Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in