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Influence of accelerated curing on the compressive strength of polymer-modified concrete

Izhar AHMAD; Kashif Ali KHAN; Tahir AHMAD; Muhammad ALAM; Muhammad Tariq BASHIR

《结构与土木工程前沿（英文）》 2022年 第16卷 第5期   页码 589-599 doi: 10.1007/s11709-022-0789-1

摘要： In recent building practice, rapid construction is one of the principal requisites. Furthermore, in designing concrete structures, compressive strength is the most significant of all parameters. While 3-d and 7-d compressive strength reflects the strengths at early phases, the ultimate strength is paramount. An effort has been made in this study to develop mathematical models for predicting compressive strength of concrete incorporating ethylene vinyl acetate (EVA) at the later phases. Kolmogorov-Smirnov (KS) goodness-of-fit test was used to examine distribution of the data. The compressive strength of EVA-modified concrete was studied by incorporating various concentrations of EVA as an admixture and by testing at ages of 28, 56, 90, 120, 210, and 365 d. An accelerated compressive strength at 3.5 hours was considered as a reference strength on the basis of which all the specified strengths were predicted by means of linear regression fit. Based on the results of KS goodness-of-fit test, it was concluded that KS test statistics value (D) in each case was lower than the critical value 0.521 for a significance level of 0.05, which demonstrated that the data was normally distributed. Based on the results of compressive strength test, it was concluded that the strength of EVA-modified specimens increased at all ages and the optimum dosage of EVA was achieved at 16% concentration. Furthermore, it was concluded that predicted compressive strength values lies within a 6% difference from the actual strength values for all the mixes, which indicates the practicability of the regression equations. This research work may help in understanding the role of EVA as a viable material in polymer-based cement composites.

关键词： compressive strength prediction     polymer-modified concrete     linear regression fit     early age strength     ethylene vinyl acetate    

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Age-related trends in genetic parameters for wood properties in

Chao SUN, Meng LAI, Shougong ZHANG, Xiaomei SUN

《农业科学与工程前沿（英文）》 2017年 第4卷 第4期   页码 482-492 doi: 10.15302/J-FASE-2017184

摘要： Wood properties are important traits that determine quality of structural wood. With the aim of performing efficient early selection for wood properties, we investigated genetic variation in 20 clones aged from 4 to 15 years for four quality traits: wood density, wall thickness to lumen area, microfibrillar angle (MFA) and modulus of elasticity (MOE). We observed that age-related trends in overall means varied for different traits: MFA decreased with the age, while the others generally increased with the age. Phenotypic variance always showed significant differences from the age of 8 years onward, with CVG ranging from 4% to 25%. Also, clonal repeatability increased steadily until 9 years old and then kept medium or higher intensity (0.4–0.8). After the age of 6, genetic correlations were generally higher than phenotypic correlations. Estimates of early selection efficiency suggested that the optimal selection age for wood density was at age 5–6 years, while it was 9–10 years for the other traits. In combination with previous results, we proposed a comprehensive early selection strategy for larch clonal breeding that involved selection based on nursery rooting ability, phenology, growth traits, and wood properties.

关键词： early selection     genetic variation     wood properties     SilviScan     Larix kaempferi    

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Development trend of urban design in “digital age”: Pan-dimensionality and individual-ubiquity

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 569-575 doi: 10.1007/s11709-021-0735-7

摘要： The wave of “digital age” featuring digital information is coming. Digital technology is profoundly changing the societal development direction and evolution paths. It also has significant bearing on production modes, social interactions and lifestyles. With regard to urban design, a system of knowledge about the creation and adaptation of material space forms that integrate humanities, art, technology and materials, digital technology has provided it with a brand-new and revolutionary scientific impetus for its evolution. The result of this evolution is “digital urban design paradigm based on human-computer interaction”, i.e., the urban development is moving toward “pan-dimensionality” and “individual ubiquity”. The future of urban design will construct a new approach to urban research and engineering, which is more complex, capable of accommodating and compatible with multiple goals of “instrumental rationality” and “value rationality”. Such a new approach shall be led by the probabilistic theory of “gray scale thinking”, reflecting quaternary synergetic view of “scientific rationality, ecological rationality, cultural rationality and technical rationality” to realize the cognitive progress of “engineering for the benefit of mankind”.

关键词： digital age     urban design     multiple objectives     human-computer interaction     pan-dimensionality     individual-ubiquity    

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Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 58-65 doi: 10.1007/s11705-017-1610-x

摘要： The advent of synthetic biology has ushered in new applications of cell-free transcription-translation systems. These cell-free systems are reconstituted using cellular proteins, and are amenable to modular control of their composition. Here, we discuss the historical advancement of cell-free systems, as well as their new applications in the rapid design of synthetic genetic circuits and components, directed evolution of biomolecules, diagnosis of infectious diseases, and synthesis of vaccines. Finally, we present our vision on the future direction of cell-free synthetic biology.

关键词： cell-free system     application    

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Opportunities and challenges for a Golden Age of chemical engineering

Phillip R. WESTMORELAND

《化学科学与工程前沿（英文）》 2014年 第8卷 第1期   页码 1-7 doi: 10.1007/s11705-014-1416-z

摘要： Chemical engineering is entering a new Golden Age of practice, thought, and impact, accompanied by great new opportunities and challenges. Five aspects mark this development: a new abundance of hydrocarbons; the evolution of biology into a molecular science; the ubiquity of powerful computational tools; the trend in manufacturing to be more process-oriented; and the systems approach that is part of ChE education from its first stages. There are important technical challenges, including technology creation and environmental impact, but just as important are new appreciation for and attention to challenges that require societal dialogues about complexity, uncertainty, and evolving and sometimes contradictory requirements. Crucial to all these impacts is enhancing the identity of what the profession is. That must be based on recognizing that the core of chemical engineering is applying molecular sciences to create value and advance the quality of life.

关键词： hydrocarbons     biotechnology     computation     cyberinfrastructure     manufacturing     environmental    

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Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 323-329 doi: 10.1007/s11684-009-0061-2

摘要： The purpose of this article is to determine the effect of a well-designed combined aerobic, resistance, and extension exercise program on bone mineral density (BMD) in postmenopausal women. The population comprised 45 postmenopausal women, who exercised over 12months (exercise group), and 36 women who served as a non-training control group. BMD of the hip, and lumbar spine was measured at the baseline and 12th month. Repeated measurement analysis of variance and nonparametric test were utilized to compare differences between the exercise group and controls. Thirty-six out of 45 persons in the exercise group and 36 controls completed the study. Average compliance was 82.2% for the whole exercise group at the 12th month. All the subjects had decreased BMD, but the rate of bone loss was lower in the exercise group than in the control group at the L4 and hip. Although the exercise program in this study may probably reduce the rate of bone loss in weight-bearing skeletal sites, we do not suggest the exercise by itself be viewed as prevention or treatment for osteoporosis. Further, the exact dose-response relationship of exercise and bone mass in early postmenopause is not clear.

关键词： early postmenopausal women     bone mineral density     exercise     effects    

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RESEARCH AND APPLICATION OF CROP PEST MONITORING AND EARLY WARNING TECHNOLOGY IN CHINA

《农业科学与工程前沿（英文）》 2022年 第9卷 第1期   页码 19-36 doi: 10.15302/J-FASE-2021411

摘要：

The importance of food security, especially in combating the problem of acute hunger, has been underscored as a key component of sustainable development. Considering the major challenge of rapidly increasing demands for both food security and safety, the management and control of major pests is urged to secure supplies of major agricultural products. However, owing to global climate change, biological invasion (e.g., fall armyworm), decreasing agricultural biodiversity, and other factors, a wide range of crop pest outbreaks are becoming more frequent and serious, making China, one of the world’s largest country in terms of agricultural production, one of the primary victims of crop yield loss and the largest pesticide consumer in the world. Nevertheless, the use of science and technology in monitoring and early warning of major crop pests provides better pest management and acts as a fundamental part of an integrated plant protection strategy to achieve the goal of sustainable development of agriculture. This review summarizes the most fundamental information on pest monitoring and early warning in China by documenting the developmental history of research and application, Chinese laws and regulations related to plant protection, and the National Monitoring and Early Warning System, with the purpose of presenting the Chinese model as an example of how to promote regional management of crop pests, especially of cross border pests such as fall armyworm and locust, by international cooperation across pest-related countries.

 

关键词： China / law / early warning system and national crop pest monitoring / pest management / regulation and sustainable agricultural development    

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Expression of inducible nitric oxide synthase in trophoblasts and deciduas in early medical abortion

Geqing XIA, Chaoying WU

《医学前沿（英文）》 2009年 第3卷 第2期   页码 216-219 doi: 10.1007/s11684-009-0028-3

摘要： The purpose of this study was to investigate the expression of inducible nitric oxide synthase in trophoblasts and deciduas in early medical abortion, and study the relationship of medical abortion through mifepristone and inducible nitric oxide synthase (iNOS) in early pregnancy. Expression of iNOS in trophoblasts and deciduas was detected by both hybridization and immunohistochemical assay in 40 patients (experimental group); the positive expression of iNOS was represented by number density (N/S) and positive unit (Pu) using computer color magic image analysis system (CMIAS). All results were compared with that obtained from vacuum aspiration. In the experimental group, N/S and Pu in trophoblasts were 0.120 ± 0.010 and 15.3 ± 2.6, respectively, while in the control group, they were 0.021 ± 0.003 and 3.1 ± 0.5, respectively, and there were significant differences between the two groups. By immunohistochemical assay, N/S and Pu were 0.090 ± 0.010, 10.24 ± 1.55 0.016 ± 0.002, 1.26 ± 0.33 in the trophoblasts of the two groups; there were also significant differences between the two groups. There were lower iNOS expressions in deciduas by in situ hybridization and immunohistochemical assay, and the difference between the two groups was not significant.It was concluded that mifepristone induced medical abortion through the expression of iNOS in trophoblasts but not in deciduas.

关键词： mifepristone     inducible nitric oxide synthase     early pregnancy     placental immunity    

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Epidemiological studies of women under age 30 infected with human papillomavirus

Zhihua LIU MD, Qing LI BM, Weihong LI BM,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 459-462 doi: 10.1007/s11684-009-0084-8

摘要： The aim of this paper was to investigate the prevalence of human papilloma virus (HPV) infection in women under 30 years old with cervical intraepithelial neoplasia (CIN) or cervical cancer, in order to provide a basis for cervical cancer prevention and treatment. We recruited 2052 female cases from the education system in Futian District, Shenzhen city, from April 2006 to April 2008, with age ranging from 22 to 60 years old. Second-generation hybrid capture test was done for detection of female genital tract HPV and cervical colposcopy for screening CIN or cervical cancer. The prevalence of HPV and cervical precancerous lesions or cervical cancer was evaluated in different age groups of women. The HPV positive rate was 247/2052 (12.00%), and 35/2052 (1.71%) of the cases were≥CIN I by pathological diagnosis. In the 22―29-year-old age group, there were 291 cases, including 39HPV-positive cases (13.40%) and one case of pathological diagnosis≥CIN I (0.34%), and there were 1761 cases in the 30―60-year-old age group, including 208 HPV-positive cases (11.81%) and 34 cases of pathological diagnosis≥CIN I (1.93%). The HPV-positive rate of 22―29-year-old age group was higher than that of 30―60-year-old age group, but the difference was not significant ( = 0.5967, = 0.4398); the CIN and cervical cancer detection rate of the former group was lower than that of the latter one, and the difference was not significant either ( = 3.7519, = 0.0527). The cases in 30―60-year-old age group were divided into five age sub-groups, and the HPV-positive rate of the 22―29-year-old age group was compared with the remaining groups, and it was found that the HPV-positive rate of the former group (13.40%) was lower than that of the 40―44-year-old age group (14.70%) but higher than that of the other four groups. Moreover, the difference in the HPV-positive rate between the 22―29-year-old age group and the 50―60-year-old age group (6.06%) was significant ( = 5.545, = 0.018), but the difference between the 22― 29-year-old age group and each of the other four groups was not significant (>0.05). In addition, the CIN and cervical cancer detection rate of the 22―29-year-old age group (0.34%) was lower than that of the remaining five groups, and the difference between the 22―29-year-old age group and the 35―39-year-old age group (2.26%), and between 22―29-year-old age group and 40―44-year-old age group (2.30%) was significant ( = 4.446, = 0.0035; = 4.525, = 0.0363, respectively), but the difference between the 22―29-year-old age group and each of other three groups was not significant (>0.05). Furthermore, 80.00% (28/35) cases of pathological diagnosis≥CIN I and 90.91% (10/11) lesions of pathological diagnosis≥CIN II occurred at 35―49 years of age. For many young women below the age of 30 who were infected with high-risk HPV were one-off infections, so it was not appropriate to recommend HPV detection as cervical precancerous lesions or cancer screening program for women less than 30 years old. The prevention and treatment of cervical cancer should be focused on those women more than 35 years of age.

关键词： cervical cancer     human papilloma virus     cervical intraepithelial neoplasia    

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Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

《医学前沿（英文）》 2014年 第8卷 第4期   页码 464-470 doi: 10.1007/s11684-014-0338-y

摘要：

Approximately one million hysterectomies are performed each year in China. However, national data regarding the indications and the surgical approaches for hysterectomy are lacking. The aim of this study was to examine the surgical indications for hysterectomy in different age groups and the relative merits of different surgical approaches for hysterectomy in Chinese women. Clinical data from 4653 cases of hysterectomy performed in Tongji Hospital from 2004 to 2009 were analysed. Hysterectomy was most commonly performed among women aged 40--49 years (2299; 49.4%). Overall, colporrhagia and abdominal pain were the two most common indications for hysterectomy. The most common indications by age groups were as follows: malignant ovarian tumour,<20 years; malignant uterine tumour, 20--29 and 30--39 years; uterine myoma, 40--49 and 50--59 years; and uterine prolapse, 60--69 and>70 years. The proportion of malignant aetiology also varied by age, being the highest in women aged<20 years (75.0%) and the lowest in those aged 40--49 years (19.9%). Approximately 35% women who had hysterectomies also had concomitant bilateral oophorectomy. The lowest rate of oophorectomy occurred in women aged 30--39 years (15.8%), whereas the highest rate was in those aged 50--59 years (75.9%). The abdominal surgical approach was used in 84% of all hysterectomies. Surgeries using the vaginal approach required a significantly shorter operating time (118 min average) than all other approaches (P<0.05). Both the amount of bleeding and the blood transfusion volume required were smaller in vaginal approaches, with no significant differences between the others. The surgical approaches used were also related to the scope of surgery. Both the surgical indications and the rates of bilateral oophorectomy varied by age. In terms of both operating time and the amount of bleeding and blood transfusion volume required, the vaginal approach was superior to all other surgical approaches.

关键词： hysterectomy     surgical indications     surgical approach     bilateral oophorectomy    

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Role of chemerin/CMKLR1 in the maintenance of early pregnancy

Xuezhou Yang, Junning Yao, Qipeng Wei, Jinhai Ye, Xiaofang Yin, Xiaozhen Quan, Yanli Lan, Hui Xing

《医学前沿（英文）》 2018年 第12卷 第5期   页码 525-532 doi: 10.1007/s11684-017-0577-9

摘要：

Chemerin is a cytokine that attracts much attention in the reproductive process. This study aimed to explore the effects of chemerin and its receptor chemokine-like receptor 1 (CMKLR1) on the maintenance of early pregnancy. The expression levels of chemerin and CMKLR1 in the decidua tissues of 20 early normal pregnant women and 20 early spontaneous abortion women were examined by Western blot and real-time polymerase chain reaction analyses. CMKLR1 receptor antagonist (α-NETA) was then intrauterinely injected into normal pregnant mice model to assess its effect on the outcome of pregnancy and the phosphorylation rate of ERK1/2 in decidua tissues. We found that the expression level of chemerin in women who had experienced early spontaneous abortion was lower than in those who had experienced normal early pregnancy (P<0.01); conversely, CMKLR1 expression was higher in the former than in the latter (P<0.01). In a pregnant-mouse model, the embryo resorption rate of α-NETA group was higher than that in the negative control group (61.5% vs. 10.8%) (P<0.001). Compared with the control group, ERK1/2 phosphorylation in decidua tissues decreased in the α-NETA-treated group (P<0.01). These results suggested that the inhibition of the chemerin/CMKLR1 signaling pathway can lead to the abortion of mouse embryos, and that chemerin/CMKLR1 may play an important role in the maintenance of early pregnancy possibly by regulating ERK1/2 phosphorylation.

关键词： chemerin     CMKLR1     early abortion    

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Weak characteristic information extraction from early fault of wind turbine generator gearbox

Xiaoli XU, Xiuli LIU

《机械工程前沿（英文）》 2017年 第12卷 第3期   页码 357-366 doi: 10.1007/s11465-017-0423-4

摘要：

Given the weak early degradation characteristic information during early fault evolution in gearbox of wind turbine generator, traditional singular value decomposition (SVD)-based denoising may result in loss of useful information. A weak characteristic information extraction based on µ-SVD and local mean decomposition (LMD) is developed to address this problem. The basic principle of the method is as follows: Determine the denoising order based on cumulative contribution rate, perform signal reconstruction, extract and subject the noisy part of signal to LMD and µ-SVD denoising, and obtain denoised signal through superposition. Experimental results show that this method can significantly weaken signal noise, effectively extract the weak characteristic information of early fault, and facilitate the early fault warning and dynamic predictive maintenance.

关键词： wind turbine generator gearbox     µ-singular value decomposition     local mean decomposition     weak characteristic information extraction     early fault warning    

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Early-onset diabetes: an epidemic in China

Jiemin Pan, Weiping Jia

《医学前沿（英文）》 2018年 第12卷 第6期   页码 624-633 doi: 10.1007/s11684-018-0669-1

摘要：

Although type 2 diabetes is a disease often associated with aging, the global prevalence of early-onset diabetes has been increasing due to man’s sedentary lifestyle, low-physical activity, obesity, and some non-modifiable risk factors. Many studies have found that individuals with early-onset type 2 diabetes were at higher risk of developing vascular complications than those with late-onset diabetes. Individuals with early-onset diabetes are usually unwilling to visit hospital and have more confidence in their health, which results in poor glycemic control and the delayed detection of diabetes-related complications. Few studies have focused on the treatment and prevention of complications in specific population of individuals with early-onset type 2 diabetes. Therefore, focusing on this particular population is critical for the government and academic societies. Screening for T2DM is imminent for young adults with a family history of diabetes, obesity, markers of insulin resistance, or alcohol consumption. More data are definitely required to establish a reasonable risk model to screen for early-onset diabetes.

关键词： diabetes     early-onset     diabetes complications    

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Biosensor-based assay of exosome biomarker for early diagnosis of cancer

《医学前沿（英文）》 2022年 第16卷 第2期   页码 157-175 doi: 10.1007/s11684-021-0884-z

摘要： Cancer imposes a severe threat to people’s health and lives, thus pressing a huge medical and economic burden on individuals and communities. Therefore, early diagnosis of cancer is indispensable in the timely prevention and effective treatment for patients. Exosome has recently become an attractive cancer biomarker in noninvasive early diagnosis because of the unique physiology and pathology functions, which reflects remarkable information regarding the cancer microenvironment, and plays an important role in the occurrence and evolution of cancer. Meanwhile, biosensors have gained great attention for the detection of exosomes due to their superior properties, such as convenient operation, real-time readout, high sensitivity, and remarkable specificity, suggesting promising biomedical applications in the early diagnosis of cancer. In this review, the latest advances of biosensors regarding the assay of exosomes were summarized, and the superiorities of exosomes as markers for the early diagnosis of cancer were evaluated. Moreover, the recent challenges and further opportunities of developing effective biosensors for the early diagnosis of cancer were discussed.

关键词： biosensor     exosome     cancer diagnosis    

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独头巷道空气年龄及通风有效性评价研究

王海桥,田峰,黄俊歆,陈涛

《中国工程科学》 2007年 第9卷 第11期   页码 43-47

摘要：

根据独头巷道作业空间的特点，给出了独头巷道局部空气年龄、平均空气年龄的定义及其计算模型，用示踪气体测定平均空气年龄的方法和原理，并用CFD (computational fluid dynamics)对独头巷道附壁受限射流通风流场及平均空气年龄进行了数值计算，得出了独头巷道空间通风流场和平均空气年龄分布，建立了计算换气效率和排污效率的数学模型。研究表明影响通风有效性的主要因素是空气年龄和污染物浓度，而影响空气年龄主要是通风气流组织和通风量。为评价独头巷道通风有效性提供了一种新的理论依据。

关键词： 独头巷道     平均空气年龄     通风有效性     换气效率     排污效率    

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标题 作者 时间 类型 操作

Influence of accelerated curing on the compressive strength of polymer-modified concrete

Izhar AHMAD; Kashif Ali KHAN; Tahir AHMAD; Muhammad ALAM; Muhammad Tariq BASHIR

期刊论文

Age-related trends in genetic parameters for wood properties in

Chao SUN, Meng LAI, Shougong ZHANG, Xiaomei SUN

期刊论文

Development trend of urban design in “digital age”: Pan-dimensionality and individual-ubiquity

期刊论文

Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

期刊论文

Opportunities and challenges for a Golden Age of chemical engineering

Phillip R. WESTMORELAND

期刊论文

Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

期刊论文

RESEARCH AND APPLICATION OF CROP PEST MONITORING AND EARLY WARNING TECHNOLOGY IN CHINA

期刊论文

Expression of inducible nitric oxide synthase in trophoblasts and deciduas in early medical abortion

Geqing XIA, Chaoying WU

期刊论文

Epidemiological studies of women under age 30 infected with human papillomavirus

Zhihua LIU MD, Qing LI BM, Weihong LI BM,

期刊论文

Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

期刊论文

Role of chemerin/CMKLR1 in the maintenance of early pregnancy

Xuezhou Yang, Junning Yao, Qipeng Wei, Jinhai Ye, Xiaofang Yin, Xiaozhen Quan, Yanli Lan, Hui Xing

期刊论文

Weak characteristic information extraction from early fault of wind turbine generator gearbox

Xiaoli XU, Xiuli LIU

期刊论文

Early-onset diabetes: an epidemic in China

Jiemin Pan, Weiping Jia

期刊论文

Biosensor-based assay of exosome biomarker for early diagnosis of cancer

期刊论文

独头巷道空气年龄及通风有效性评价研究

王海桥,田峰,黄俊歆,陈涛

期刊论文