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Immunohistochemical measurement and expression of Mcl-1 in infertile testes

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《医学前沿（英文）》 2015年 第9卷 第3期   页码 361-367 doi: 10.1007/s11684-015-0395-x

摘要：

The diagnosis of azoospermia represents a major challenge to andrologists as this condition may occur despite normal spermatogenesis and genital tracts. Myeloid cell leukemia-1 (Mcl-1) is a member of the Bcl-2 family of proteins involved in regulation of apoptosis in various cell types. This study aimed to investigate the immunohistochemical expression of Mcl-1 in testicular biopsies of subjects with azoospermia. Eighty-six cases with azoospermia were obtained from 509 infertile patients admitted to the Andrology Unit of the Zagazig University Hospitals from January 2010 to December 2011. Biopsies were diagnosed and classified using H&E-stained slide sections. The specimens were subjected to immunohistochemical staining for Mcl-1 and examined through light microscopy. Forty-five cases of maturation arrest (25 at spermatids and 20 at the spermatocytes), 31 cases of hypospermatogenesis (20 moderate and 11 severe), 5 cases of Sertoli?cell-only syndrome, 2 cases of basement membrane hyalinization, and 1 case of tubular and peritubular sclerosis were observed. Normal spermatogenesis was detected in 2 cases. A strong positive immunoreaction in Leydig cells was observed among all investigated specimens. A moderate reaction was detected in spermatocytes and spermatozoa in cases of normal spermatogenesis and hypospermatogenesis, but a negative reaction was detected in cases of maturation arrest and germ cell aplasia. Apoptosis was found to be associated with decreased rate of spermatogenesis. High apoptosis rates may result in azoospermia, which can occur despite normal spermatogenesis and absence of duct obstruction.

关键词： spermatogenesis     testis     Mcl-1 expression     immunohistochemical study     infertility    

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Immunohistochemical characterization of hepatic stem cell-related cells in developing human liver

XU Jun, HU Yong, WANG Jian, ZHANG Taiping, ZHOU Ji, YU Hongyu

《医学前沿（英文）》 2007年 第1卷 第3期   页码 264-268 doi: 10.1007/s11684-007-0050-2

摘要： Little is known about the expression characteristics of the various kinds of possible markers in hepatic stem cells (HSCs) and other HSC-related cells in human fetal liver in various developmental stages. It is significant to investigate the immunohistochemical expression for better understanding of the origin, differentiation and migration of HSCs in the developing human liver. H-E staining and immunohistochemical methods were used to observe the expression of hepatic/cholangiocellular differentiation markers (AFP, GST-, CK7, CK19) and hematopoietic stem cell markers (CD34 and c-kit) in several kinds of HSC-related cells in thirty cases of fetal liver samples (4–35 weeks after pregnancy). AFP expression appears in fetal hepatocytes at four weeks’ gestation. It peaks at 16–24 weeks’ gestation and decreases gradually afterwards. Finally, weak signals were only found in some ductal plate cells and a few limiting plate cells. GST- was detected in hepatic cord cells from the sixth week and in the ductal plate cells from the eighth week. Twenty-six weeks later, only some ductal plate cells and a few limiting plate cells show positive signals. CK19 expression peaks during the 6th–11th weeks in hepatic cord cells and decreases gradually afterwards, except for the ductal plates. CK7 expression was limited in the ductal plate cells and bile ducts cells from the 14th week. CD34 and c-kit were detected at the eighth week in some ductal plate cells and a few mononuclear cells in the hepatic cords/mesenchymal tissue of portal areas. After 21 weeks, CD34 and c-kit were found only in ductal plate cells and a few mononuclear cells in the hepatic mesenchymal tissue of portal areas. Fetal hepatocytes at 4–16 weeks’ gestation are mainly constituted by HSCs characterized with bi-potential differentiation capacity. At 16 weeks’ gestation, most hepatic cord cells begin to differentiate into hepatocytes and abundant HSCs remain in ductal plate (the origin site of Hering canals). It is also indicated that the hematopoietic stem cells may give rise to some HSCs in embryonic liver. These indirectly support the hypothesis about the location and origin of HSCs in liver valley hypothesis reported previously.

关键词： origin     Little     mesenchymal tissue     cords/mesenchymal tissue     CD34    

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Scale study of sites and pavilions for World Expo 2010

ZHOU Zhuoyan, CHEN Yi

《结构与土木工程前沿（英文）》 2008年 第2卷 第1期   页码 102-106 doi: 10.1007/s11709-008-0012-z

摘要： The scale of sites and pavilions for World Expo 2010 (Shanghai World Expo) mainly refers to the study of their size including the area and number of exhibition hall needed in each pavilion and site with appropriate waiting area. All the design data of scale studied should reasonably meet the requirements during World Expo 2010 to accommodate large number of people for visiting and waiting to the full.

关键词： pavilion     study     number     appropriate     design    

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Practicality study on air-powered vehicle

LIU Lin, YU Xiaoli

《能源前沿（英文）》 2008年 第2卷 第1期   页码 14-19 doi: 10.1007/s11708-008-0004-7

摘要： To investigate the feasibility and outlook of air-powered vehicles including compressed air-powered vehicle and liquid nitrogen-powered vehicle, thermodynamic analysis and experiment data were used to analyze the energy density, performance, safety, running efficiency, fuel circulation economy and consumer acceptance, etc. The results show that compressed air and liquid nitrogen have similar energy density as Ni-H battery; the characteristics of an air-powered engine is suitable for driving a vehicle; the circulation efficiency of liquid nitrogen is 3.6%–14% and that of compressed air is 25%–32.3% in practice, and existing technology can assure its safety. It is concluded that though the performance of an air-powered engine is inferior to that of the traditional inert combustion engine, an air-powered vehicle is fit for future green cars to realize the sustainable development of society and environment.
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Experimental study on shear behavior of prestressed reactive powder concrete I-girders

Hui ZHENG, Zhi FANG, Bin CHEN

《结构与土木工程前沿（英文）》 2019年 第13卷 第3期   页码 618-627 doi: 10.1007/s11709-018-0500-8

摘要： As a new generation of concrete, RPC(Reactive Powder Concrete) has attracted great research attention for its ultra-high strength and high durability. In the present paper, experimental results from tests on eight prestressed RPC I-section girders failing in shear are reported herein. The beams with RPC of 120 MPa in compression were designed to assess the ability to carry shear stress in thin webbed prestressed beams with stirrups. The test variables were the level of prestressing, shear span-depth ratio ( / ) and stirrup ratio. Shear deformation, shear capacity and crack pattern were experimentally investigated in detail. With regard to the shear resistance of the test beams, the predictions from three standards (AFGC, JSCE and SIA) on the design of UHPC structures were compared with the experimental result suggesting that the experimental strength is almost always higher than predicted. RPC, as a new concrete, was different from normal concrete and fiber reinforced concrete. Further study should be needed to develop an analytical method and computation model for shear strength of RPC beams.

关键词： prestressed concrete     RPC(Reactive Powder Concrete)     concrete beams     shear strength     experimental study    

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A feasibility study of the measuring accuracy and capability of wireless sensor networks in tunnel monitoring

Xiaojun LI, Zhong JI, Hehua ZHU, Chen GU

《结构与土木工程前沿（英文）》 2012年 第6卷 第2期   页码 111-120 doi: 10.1007/s11709-012-0150-1

摘要： Fire disasters and the deterioration of tunnel structures are major concerns for tunnel operation and maintenance. Traditional wired monitoring systems have many drawbacks in terms of installation time, overall cost, and flexibility in tunnel environments. In recent years, there has been growing interest in the use of wireless sensor networks (WSNs) for the monitoring of various structural monitoring applications. This paper evaluated the feasibility of applying a WSN in the monitoring of tunnels. The monitoring requirements of tunnels under explosion and combustion fire scenarios are analyzed using numerical simulation, and the maximum possible distance for temperature sensors is derived. The displacement monitoring of tunnels using an inclinometer is investigated. It is recommended that the inclinometer should be installed in the 1/4 span of the tunnel structure. The maximum wireless transmission distances in both outdoor and tunnel environments were examined. The influences of surface materials and sensor node locations on the data transmission distance in tunnel environments were also investigated. The experimental results show that the data loss in tunnel environments is approximately three times that in outdoor environments. Surface material has a considerable influence on the transmission distance of radio signals. The distance is 25 ? 28 m for a raw concrete surface, 20 m for a brick surface, and 36 m for a terrazzo surface. The transmission distances along the middle of quarter points are approximately 0.9 ( is the transmission distance in the center of the tunnel), and the relative error is less than±3%. The transmission distances at different locations along the bottom exhibit significant differences, decreasing from the middle to the corner point, with distances of approximately 0.8 at the quarter points and minimum distances of approximately 0.55 at the corner points.

关键词： wireless sensor network (WSN)     tunnel     monitoring     feasibility study    

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Antimicrobial activity of topical agents against Propionibacterium acnes: an in vitro study of clinical

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《医学前沿（英文）》 2016年 第10卷 第4期   页码 517-521 doi: 10.1007/s11684-016-0480-9

摘要：

This study aimed to compare the antimicrobial activities of topical agents against Propionibacterium acnes isolated from patients admitted to a hospital in Shanghai, China. The minimal inhibitory concentrations of the cultured P. acnes were determined in accordance with the Clinical and Laboratory Standards Institute. Susceptibilities to clindamycin and erythromycin were compared in terms of gender, age, disease duration, previous treatment, and disease severity. A total of 69 P. acnes strains were isolated from 98 patients (70.41%). The susceptibility to triple antibiotic ointment (neomycin/bacitracin/polymyxin B) and bacitracin was 100%. The susceptibility to fusidic acid was 92.7%. The resistance rates to neomycin sulfate, erythromycin, and clindamycin were 11.7%, 49.3%, and 33.4%, respectively. The high resistance rate to clindamycin and erythromycin was significantly affected by gender, previous treatment, and disease severity rather than by age and disease duration. Topical antibiotics should not be used separately for long-term therapy to avoid multiresistance. The use of topical antibiotics should be determined by clinicians on the basis of clinical conditions.

关键词： antimicrobial susceptibility/resistance     Propionibacterium acnes     topical antibiotics     in vitro study    

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Genetic study and molecular breeding for high phosphorus use efficiency in maize

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《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 366-379 doi: 10.15302/J-FASE-2019278

摘要：

Phosphorus is the second most important macronutrient after nitrogen and it has many vital functions in the life of plants. Most soils have a low available P content, which has become a key limiting factor for increasing crop production. Also, low P use efficiency (PUE) of crops in conjunction with excessive application of P fertilizers has resulted in serious environmental problems. Thus, dissecting the genetic architecture of crop PUE, mining related quantitative trait loci (QTL) and using molecular breeding methods to improve high PUE germplasm are of great significance and serve as an efficient approach for the development of sustainable agriculture. In this review, molecular and phenotypic characteristics of maize inbred lines with high PUE, related QTL and genes as well as low-P responses are summarized. Based on this, a breeding strategy applying genomic selection as the core, and integrating the existing genetic information and molecular breeding techniques is proposed for breeding high PUE maize inbred lines and hybrids.

关键词： maize     phosphorus use efficiency     quantitative trait loci     genetic study     molecular breeding     genomic selection    

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Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed

《结构与土木工程前沿（英文）》   页码 1145-1162 doi: 10.1007/s11709-023-0945-2

摘要： To realize seismic-resilient reinforced concrete (RC) moment-resisting frame structures, a novel self-centering RC column with a rubber layer placed at the bottom (SRRC column) is proposed herein. For the column, the longitudinal reinforcement dissipates seismic energy, the rubber layer allows the rocking of the column, and the unbonded prestressed tendon enables self-centering capacity. A refined finite element model of the SRRC column is developed, the effectiveness of which is validated based on experimental results. Results show that the SRRC column exhibits stable energy dissipation capacity and no strength degradation; additionally, it can significantly reduce permanent residual deformation and mitigate damage to concrete. Extensive parametric studies pertaining to SRRC columns have been conducted to investigate the critical factors affecting their seismic performance.

关键词： seismic resilience     self-centering     rubber layer     flag-shaped hysteresis loop     parametric study    

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Experimental study on the laminar flame speed of hydrogen/natural gas/air mixtures

Chen DONG, Qulan ZHOU, Xiaoguang ZHANG, Qinxin ZHAO, Tongmo XU, Shi’en HUI

《化学科学与工程前沿（英文）》 2010年 第4卷 第4期   页码 417-422 doi: 10.1007/s11705-010-0515-8

摘要： Laminar flame speeds of hydrogen/natural gas/air mixtures have been measured over a full range of fuel compositions (0–100% volumetric fraction of H ) and a wide range of equivalence ratio using Bunsen burner. High sensitivity scientific CCD camera is use to capture the image of laminar flame. The reaction zone area is employed to calculate the laminar flame speed. The initial temperature and pressure of fuel air mixtures are 293 K and 1 atm. The laminar flame speeds of hydrogen/air mixture and natural gas/air mixture reach their maximum values 2.933 and 0.374 m/s when equivalence ratios equal to 1.7 and 1.1, respectively. The laminar flame speeds of hydrogen/natural gas/air mixtures rise with the increase of volumetric fraction of hydrogen. Moreover, the increase in laminar flame speed as the volumetric fraction of hydrogen increases presents an exponential increasing trend versus volumetric fraction of hydrogen. Empirical formulas to calculate the laminar flame speeds of hydrogen, natural gas, and hydrogen/natural gas mixtures are also given. Using these formulas, the laminar flame speed at different hydrogen fractions and equivalence ratios can be calculated.

关键词： laminar flame speed     experimental study     Bunsen flame    

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and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action (EQIA) study: a national cohort study in China from 2017 to 2019

《医学前沿（英文）》 doi: 10.1007/s11684-023-1014-x

摘要： This cohort study was performed to explore the influence of intensive care unit (ICU) quality on in-hospital mortality of veno-venous (V-V) extracorporeal membrane oxygenation (ECMO)-supported patients in China. The study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2017 to 2019, using data from the National Clinical Improvement System and China National Critical Care Quality Control Center. ICU quality was assessed by quality control indicators and capacity parameters. Among the 2563 V-V ECMO-supported patients in 318 hospitals, a significant correlation was found between ECMO-related complications and prognosis. The reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients (cutoff: 1.5% and 7.0%; 95% confidence interval: 1.05–1.48 and 1.04–1.45; odds ratios: 1.25 and 1.23; P = 0.012 and P = 0.015, respectively). Meanwhile, the V-V ECMO center volume was a protective factor (cutoff of ≥ 50 cases within the 3-year study period; 95% confidence interval: 0.57–0.83, odds ratio: 0.69, P = 0.0001). The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these findings. Thus, ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

关键词： veno-venous extracorporeal membrane oxygenation     in-hospital mortality     high-volume centers     quality control     intensive care unit capacity parameters    

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Microplastics in municipal wastewater treatment plants: a case study of Denizli/Turkey

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1699-8

摘要：

● High amounts of microplastics are released to receiving media from WWTPs.

关键词： Microplastics     Wastewater treatment plant     Removal efficiency     Daily discharge    

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Theoretical study on the mechanism of sulfur migration to gas in the pyrolysis of benzothiophene

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 334-346 doi: 10.1007/s11705-022-2209-4

摘要： The release and control of sulfur species in the pyrolysis of fossil fuels and solid wastes have attracted attention worldwide. Particularly, thiophene derivatives are important intermediates for the sulfur gas release from organic sulfur, but the underlying migration mechanisms remain unclear. Herein, the mechanism of sulfur migration during the release of sulfur-containing radicals in benzothiophene pyrolysis was explored through quantum chemistry modeling. The C1-to-C2 H-transfer has the lowest energy barrier of 269.9 kJ·mol–1 and the highest rate constant at low temperatures, while the elevated temperature is beneficial for C−S bond homolysis. 2-Ethynylbenzenethiol is the key intermediate for the formation of S and SH radicals with the overall energy barriers of 408.0 and 498.7 kJ·mol–1 in favorable pathways. The generation of CS radicals is relatively difficult because of the high energy barrier (551.8 kJ·mol–1). However, it can be significantly promoted by high temperatures, where the rate constant exceeds that for S radical generation above 930 °C. Consequently, the strong competitiveness of S and SH radicals results in abundant H2S during benzothiophene pyrolysis, and the high temperature is more beneficial for CS2 generation from CS radicals. This study lays a foundation for elucidating sulfur migration mechanisms and furthering the development of pyrolysis techniques.

关键词： benzothiophene     sulfur migration     pyrolysis     density functional theory    

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标题 作者 时间 类型 操作

Immunohistochemical measurement and expression of Mcl-1 in infertile testes

null

期刊论文

Immunohistochemical characterization of hepatic stem cell-related cells in developing human liver

XU Jun, HU Yong, WANG Jian, ZHANG Taiping, ZHOU Ji, YU Hongyu

期刊论文

Scale study of sites and pavilions for World Expo 2010

ZHOU Zhuoyan, CHEN Yi

期刊论文

Practicality study on air-powered vehicle

LIU Lin, YU Xiaoli

期刊论文

Experimental study on shear behavior of prestressed reactive powder concrete I-girders

Hui ZHENG, Zhi FANG, Bin CHEN

期刊论文

A feasibility study of the measuring accuracy and capability of wireless sensor networks in tunnel monitoring

Xiaojun LI, Zhong JI, Hehua ZHU, Chen GU

期刊论文

魏明杰：聚酰胺反渗透膜渗透机制的分子模拟研究（2022年4月16日）

2022年06月09日

会议视频

Antimicrobial activity of topical agents against Propionibacterium acnes: an in vitro study of clinical

null

期刊论文

Genetic study and molecular breeding for high phosphorus use efficiency in maize

null

期刊论文

Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed

期刊论文

Experimental study on the laminar flame speed of hydrogen/natural gas/air mixtures

Chen DONG, Qulan ZHOU, Xiaoguang ZHANG, Qinxin ZHAO, Tongmo XU, Shi’en HUI

期刊论文

and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action (EQIA) study: a national cohort study in China from 2017 to 2019

期刊论文

Huiling Song：Policy to Mitigate Supply Constraint of Byproduct Metals for Clean Energy Technology: A Case Study

2022年06月10日

会议视频

Microplastics in municipal wastewater treatment plants: a case study of Denizli/Turkey

期刊论文

Theoretical study on the mechanism of sulfur migration to gas in the pyrolysis of benzothiophene

期刊论文