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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    

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    

Spatial and Temporal Variations in the Atmospheric Age Distribution of Primary and Secondary Inorganic

Xiaodong Xie,Qi Ying,Hongliang Zhang,Jianlin Hu,

《工程(英文)》 doi: 10.1016/j.eng.2022.03.013

摘要: The aging timescale of particles is a key parameter in determining their impacts on air quality, human health, and climate. In this study, a one-year simulation of the age distributions of the primary and secondary inorganic fine particulate matter (PM2.5) components was conducted over China using an age-resolved Community Multiscale Air Quality (CMAQ) model. The results indicate that primary PM2.5 (PPM) and ammonium mainly originate from fresh local emissions, with approximately 60%–80% concentrated in 0–24 h age bins in most of China throughout the year. The average age is ∼15–25 h in most regions in summer, but increases to 40–50 h in southern region of China and the Sichuan Basin (SCB) in winter. Sulfate is more aged than PPM, indicating an enhanced contribution from regional transport. Aged sulfate with atmospheric age > 48 h account for 30%–50% of total sulfate in most regions and seasons, and the concentrations in the > 96 h age bin can reach up to 15 µg·m−3 in SCB during winter. Dramatic seasonal variations occur in the Yangtze River Delta, Pearl River Delta, and SCB, with highest average age of 60–70 h in winter and lowest of 40–45 h in summer. The average age of nitrate is 20–30 h in summer and increases to 40–50 h in winter. The enhanced deposition rate of nitric acid vapor combined with the faster chemical reaction rate of nitrogen oxides leads to a lower atmospheric age in summer. Additionally, on pollution days, the contributions of old age bins (> 24 h) increase notably for both PPM and secondary inorganic aerosols in most cities and seasons, suggesting that regional transport plays a vital role during haze events. The age information of PM2.5, provided by the age-resolved CMAQ model, can help policymakers design effective emergent emission control measures to eliminate severe haze episodes.

关键词: Atmospheric age     PM     2.5     CMAQ model     Control strategy    

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    

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    

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    

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    

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    

不同民族流动育龄妇女的避孕状况分析

张君娴,杨婷,徐晓帆,龙春燕,刘建苏,李莉

《中国工程科学》 2015年 第17卷 第6期   页码 57-60

摘要:

了解乌鲁木齐市流动育龄妇女的避孕状况,为今后开展避孕方法知情选择优质服务提供参考。采用分层-整群-随机抽样的方法,对18~50岁符合条件的对象进行问卷调查,主要包括人口学特征、避孕措施的使用情况等。采用卡方检验和多因素Logistic回归方法进行统计分析。本次调查的106 568例流动育龄妇女中,避孕方法使用比例为92.78 %,避孕方法的选择依次为宫内节育器(65.74 %)、药物(23.17 %,包括口服避孕药、皮下埋植剂、避孕针等含药避孕方法)、避孕套(9.06 %)、绝育术(2.03 %)。多因素Logistic回归分析显示民族、学历、职业、婚姻状况和性生活频率对避孕方法的使用有影响。应根据不同民族的情况和流动育龄妇女的人口学特征,提供有针对性和个性化的避孕方法知情选择指导和服务。

关键词: 流动育龄妇女     避孕状况     分析    

育龄妇女非意愿妊娠原因分析与对策研究

王代权,刘长艳,向琼,马代慈

《中国工程科学》 2014年 第16卷 第5期   页码 11-15

摘要:

采取整群抽样调查方法,对2011 年1 月—2013 年5 月在秭归县、夷陵区计划生育服务站因非意愿妊娠而实行人工终止妊娠对象,通过查阅病历资料和调查问卷,了解非意愿性妊娠原因及相关因素。1 360例非意愿妊娠中,未婚为21.62 %,已婚为78.38 %;人群分布在20~39 年龄段(73.82 %);孕次分布主要在孕2~孕3 的对象为57.87 %;非意愿妊娠中避孕措施失败者为44.34 %,无措施者为55.66 %。避孕措施因素宫内节育器为10.51 %,避孕套为10.51 %,避孕药为8.24 %,外用为6.62 %,其他为8.46 %。存在侥幸心理和取出宫内节育器(IUD)后续措施没能跟进是无措施者导致非意愿妊娠的主要原因。避孕知识知晓率为98.90 %,对紧急避孕的知晓率仅为15.37 %,知道哺乳期需避孕者为18.38 %。医务人员、计生干部、宣传资料是已婚人群获取避孕知识的主要途径,农民及农民工对象获取免费服务高于城镇居民、国家工作人员、商业服务人员及外来流入人员。

关键词: 育龄妇女     非意愿妊娠     人工流产     影响因素    

Ancient road transport devices: Developments from the Bronze Age to the Roman Empire

Cesare ROSSI,Thomas G. CHONDROS,Kypros F. MILIDONIS,Sergio SAVINO,Flavio RUSSO

《机械工程前沿(英文)》 2016年 第11卷 第1期   页码 12-25 doi: 10.1007/s11465-015-0358-6

摘要:

The development of transportation systems has significantly enhanced the welfare and modernization of society. Wooden vehicles pulled by animals have been used for land transportation since the early Bronze Age. Whole-body gharries with rigid wheels pulled by oxen appeared in Crete by 2000 BC or earlier. Horses originating from the East were depicted in early Cretan seal-rings of the same period. The two-wheeled horse-drawn chariot was one of the most important inventions in history. This vehicle provided humanity its first concept of personal transport and was the key technology of war for 2000 years. Chariots of Mycenaean and Archaic Greece with light and flexible four-spoked wheels acting as spring suspensions were depicted in vase paintings. The development of this vehicle incorporated the seeds of a primitive design activity and was important for engineering. The Trojan horse since 1194 BC and the helepolis since 700 BC were the first known machines on a wheeled base transported by horses or self-powered. Ancient engineers invented bearings lubricated with fat, and Romans introduced the ancestors of ball bearings for their wagons and carts. The historic evolution of wheeled transportation systems, along with early traction, suspension, and braking systems, is presented in this paper. Analytical and numerical methods are incorporated to analyze the most conceivable loading situations of typically reconstructed wheeled transportation systems in ancient times. Traction requirements both for horse-driven machines and the power for internal motors are also analyzed. This study can serve as a basis for further development of detailed reconstruction of transportation systems in antiquity.

关键词: transportation     wheel     spoke     cart     axle     bearing    

科学的时代特征——应对全球挑战中转变范式

董超, 李静海, Daya Reddy

《工程(英文)》 2022年 第19卷 第12期   页码 22-23 doi: 10.1016/j.eng.2022.05.002

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

《结构与土木工程前沿(英文)》   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    

乌鲁木齐市流动育龄妇女阴道炎患病现况调查

张君娴,周彦岭,刘建苏,王珊,李莉,梅桂,李琳,巴哈古丽·塔吉曼提

《中国工程科学》 2014年 第16卷 第5期   页码 85-89

摘要:

了解乌鲁木齐市流动人口育龄妇女阴道炎感染患病现况,为今后的生殖道感染防治提供参考依据。本文采取分层-整群-抽样的方法,在乌鲁木齐市六区一县流动人口较集中的社区,由经过培训的医生对18~50 岁的流动育龄妇女进行生殖道感染问卷调查、妇科检查与实验室检查。本研究共检查106 568 名符合条件的流动妇女,其中细菌性阴道炎的患病率为16.15 %;滴虫性阴道炎的患病率为12.66 %;霉菌性阴道炎的患病率为4.52 %。3 种阴道炎的患病率为19.84 %。应根据不同民族的特点,采取一定的防治措施,降低流动育龄妇女的阴道炎患病率,特别是对文化程度为文盲或小学、职业为农民、月收入在1 500~1 599 元的对象,应加大干预的力度。

关键词: 流动育龄妇女     阴道炎     患病现况    

Transcriptome resources and genome-wide marker development for Japanese larch (

Wanfeng LI,Suying HAN,Liwang QI,Shougong ZHANG

《农业科学与工程前沿(英文)》 2014年 第1卷 第1期   页码 77-84 doi: 10.15302/J-FASE-2014010

摘要: While the differential responses of trees to changes in climatic and environmental conditions have been demonstrated as they age, the underlying mechanisms and age control of tree growth and development are complex and poorly understood particularly at a molecular level. In this paper, we present a transcriptome analysis of , a deciduous conifer that is widely-grown in the northern hemisphere and of significant ecological and economic value. Using high-throughput RNA sequencing, we obtained about 26 million reads from the stems of 1-, 2-, 5-, 10-, 25- and 50-year-old trees. Combining these with the published Roche 454 sequencing reads and the expressed sequence tags (both mainly from embryogenic cell cultures), we assembled 26670549 reads into 146786 transcripts, of which we annotated 79182 to support investigations of the molecular basis of tree aging and adaption, somatic embryogenesis and wood formation. Using these sequences we also identified many single-nucleotide polymorphisms, simple sequence repeats, and insertion and deletion markers to assist breeding and genetic diversity studies of .

关键词: Larix     transcriptome     age     wood formation     somatic embryogenesis     molecular marker    

标题 作者 时间 类型 操作

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

Spatial and Temporal Variations in the Atmospheric Age Distribution of Primary and Secondary Inorganic

Xiaodong Xie,Qi Ying,Hongliang Zhang,Jianlin Hu,

期刊论文

Opportunities and challenges for a Golden Age of chemical engineering

Phillip R. WESTMORELAND

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

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

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

不同民族流动育龄妇女的避孕状况分析

张君娴,杨婷,徐晓帆,龙春燕,刘建苏,李莉

期刊论文

育龄妇女非意愿妊娠原因分析与对策研究

王代权,刘长艳,向琼,马代慈

期刊论文

Ancient road transport devices: Developments from the Bronze Age to the Roman Empire

Cesare ROSSI,Thomas G. CHONDROS,Kypros F. MILIDONIS,Sergio SAVINO,Flavio RUSSO

期刊论文

科学的时代特征——应对全球挑战中转变范式

董超, 李静海, Daya Reddy

期刊论文

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

期刊论文

乌鲁木齐市流动育龄妇女阴道炎患病现况调查

张君娴,周彦岭,刘建苏,王珊,李莉,梅桂,李琳,巴哈古丽·塔吉曼提

期刊论文

Transcriptome resources and genome-wide marker development for Japanese larch (

Wanfeng LI,Suying HAN,Liwang QI,Shougong ZHANG

期刊论文