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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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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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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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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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The size distribution of airborne bacteria and human pathogenic bacteria in a commercial composting plant

《环境科学与工程前沿（英文）》 2021年第15卷第3期 doi: 10.1007/s11783-020-1356-4

摘要：

•Bacterial concentrations from eight stages were 10⁴–10⁵copies/m³.

关键词： Size distribution Airborne bacteria Biological diversity Human pathogenic bacteria Composting plants

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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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Particle size distribution and shape control of Au nanoparticles used for particle gun

S. Kida, M. Ichiji, J. Watanabe, I. Hirasawa

《化学科学与工程前沿（英文）》 2013年第7卷第1期页码 60-64 doi: 10.1007/s11705-013-1313-x

摘要： Au nanoparticles are expected for the media to transfer genes into plants. However, the control of particle size distribution (PSD) and shape of Au nanoparticles is too difficult to design and prepare particles with suitable quality for the gene supporting media. Reduction crystallization experiments were performed in aqueous solution in order to clarify the effect of feeding conditions such as feeding profile, feeding rate, and feeding amount on PSD and shape of Au nanoparticles. Ascorbic acid (AsA) was selected as a reducing agent because it is safe for plants. Au particles of 50 nm, 50–200 nm, and 150–400 nm were obtained in batch operation, single-jet, and double-jet, respectively. Moreover, in single-jet and double-jet, the mean size of the obtained Au particles increases with the decrease of feeding rate or the increase of feeding amount. It is concluded that PSD of Au nanoparticles can be controlled in the range of 50–400 nm by changing feeding conditions of AsA and HAuCl aqueous solution.

关键词： reduction crystallization particle size distribution gene transferring media

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A better way to do small-for-size liver transplantation in rats

null

《医学前沿（英文）》 2011年第5卷第1期页码 106-110 doi: 10.1007/s11684-011-0113-2

摘要：

Establishing a model for small-for-size liver transplantation is the basis for this study of partial and living donor graft liver transplantation. This study aims to explore a simpler and more effective way of establishing a 30% small-for-size liver transplantation in rats. Sprague-Dawley rats were selected as the donors and recipients. Small-for-size orthotopic liver transplantation was performed using Kamada’s two-cuff method. The donor’s liver was flushed via the abdominal aorta and hepatectomy was performed in situ. The animals were divided into three groups depending on the graft selected, with 40 pairs of rats in each group. In group I, the median lobe of the liver was used as graft; in group II, the right half of the median lobe and the right lobe were used as graft; and in group III, the median and right lobes were used as graft. In groups I and II, the bodyweights of donors were the same as those of recipients; however, in group III the bodyweights of donors were 100–120 g less than those of the recipients. The duration needed for transplantation, the 7-day survival rates, and the technical complication rates were compared among these three groups. The time required for hepatectomy was shorter in group III compared with groups I and II (8.8?±?0.7 min vs. 11.5?±?1.1 min and 10.1?±?1.0 min, P = 0.001). The cold ischemia time for the grafts, the anhepatic times, and the transplantation times for the recipients were not significantly different among the three groups. Compared with groups I and II, the incidence of bleeding, bile leakage, and inferior vena caval strictures were significantly decreased in group III (P<0.05). No significant differences between the three groups were found based on other complications after the operation (P>0.05). Group III had better 7-day survival rates and longer median survival times but the differences were not statistically significant. The method of small for donor bodyweight using the median and right lobes for grafting may be a more effective and simpler way of establishing a 30% small-for-size liver transplantation in rats, as shown by the shorter hepatectomy time and the occurrence of fewer complications after the operation.

关键词： liver transplantation small-for-size rats

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Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

《环境科学与工程前沿（英文）》 2022年第16卷第10期 doi: 10.1007/s11783-022-1557-0

摘要：

● A series of Cu-ZSM-5 catalysts were tested for DMF selective catalytic oxidation.

关键词： N N-Dimethylformamide Selective catalytic oxidation Cu-ZSM-5 CuO particle size

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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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Effect of particle size on coal char----NO reaction

Xiumin JIANG, Xiangyong HUANG, Jiaxun LIU, Chaoqun ZHANG

《能源前沿（英文）》 2011年第5卷第2期页码 221-228 doi: 10.1007/s11708-011-0146-x

摘要： Surface nitrogen complex formation upon reaction of coal char with NO at 600°C was studied by X-ray photoelectron spectroscopy. Particle size had a noticeable effect on the magnitude of changes, which was observed on the surface of the coal char in the nitrogen functional group. The surface increased its -NO, pyridine-N-oxide, and -NO functional group contents with a decrease in particle size. The chemisorption processes of NO molecules on the char were simulated using the ab initio Hartree–Fock method and density functional theory. Molecular modeling was applied to determine the thermodynamics of the reactions. Mechanisms were proposed to explain the formation of the -NO, pyridine-N-oxide, and -NO functional groups at 600°C.

关键词： NO reduction chemisorption particle size X-ray photoelectron spectroscopy density functional theory (DFT)

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Soot size distribution in lightly sooting premixed flames of benzene and toluene

Wang LIU, Jiaqi ZHAI, Baiyang LIN, He LIN, Dong HAN

《能源前沿（英文）》 2020年第14卷第1期页码 18-26 doi: 10.1007/s11708-020-0663-6

摘要： The evolution of particle size distribution function (PSDF) of soot in premixed flames of benzene and toluene was studied on a burner stabilized stagnation (BSS) flame platform. The cold gas velocities were changed to hold the maximum flame temperatures of different flames approximately constant. The PSDFs of all the test flames exhibited a bimodal distribution, i.e., a small-size nucleation mode and a large-size accumulation mode. It was observed that soot nucleation and particle growth in the benzene flame were stronger than those in the toluene flame at short residence times. At longer residence times, the PSDFs of the two flames were similar, and the toluene flame showed a larger particle size distribution range and a higher particle volume fraction than the benzene flame.

关键词： premixed flame soot particle size distribution function benzene toluene