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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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Review on ranking and selection: A new perspective

L. Jeff HONG, Weiwei FAN, Jun LUO

《工程管理前沿（英文）》 2021年第8卷第3期页码 321-343 doi: 10.1007/s42524-021-0152-6

摘要： In this paper, we briefly review the development of ranking and selection (R&S) in the past 70 years, especially the theoretical achievements and practical applications in the past 20 years. Different from the frequentist and Bayesian classifications adopted by Kim and Nelson (2006b) and Chick (2006) in their review articles, we categorize existing R&S procedures into fixed-precision and fixed-budget procedures, as in Hunter and Nelson (2017). We show that these two categories of procedures essentially differ in the underlying methodological formulations, i.e., they are built on hypothesis testing and dynamic programming, respectively. In light of this variation, we review in detail some well-known procedures in the literature and show how they fit into these two formulations. In addition, we discuss the use of R&S procedures in solving various practical problems and propose what we think are the important research questions in the field.

关键词： ranking and selection hypothesis testing dynamic programming simulation

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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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Control mode selection for modal control of long-span arch bridge

Zhengying LI, Zhengliang LI,

《结构与土木工程前沿（英文）》 2009年第3卷第4期页码 401-406 doi: 10.1007/s11709-009-0052-z

摘要： For seismic control of arch bridge, a model reduction of long-span arch bridge was implemented based on modal analysis. As for the critical mode selection, an approach based on the maximum modal displacement was presented. This approach takes into consideration the effect of external seismic excitation and is more reasonable than only considering dynamic bridge characteristics based on a modal contribution ratio. The time domain and frequency domain analysis method were used to verify the simplified model of the Nimu arch bridge in Tibet as an example. The numerical results show that the method of maximal modal displacement better analyze long-span arch bridge when multisupport seismic excitation must be considered. The reduced-order system also is more in line with the performance of the original model.

关键词： selection reduced-order excitation long-span simplified

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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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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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The early signal substances induced by heat stress in brains of mice

WANG Chunxu, WANG Hanxing

《医学前沿（英文）》 2008年第2卷第4期页码 391-395 doi: 10.1007/s11684-008-0075-1

摘要： To study the effects of early signal substances induced by heat stress in brains of Kunming mice, six-month-old mice ( = 72) were pretreated with heat stress and subsequent ischemia/reperfusion by clipping of their bilateral cervical common arteries for 7 min. According to different treatments, animals were randomly divided into four groups: (1) normal control group; (2) heat stress pretreatment followed by ischemia and reperfusion group (HS/IR); (3) ischemia and reperfusion group (IR); (4) heat stress group (HS). Animals in the later three groups were subdivided into 3 subgroups (1 day, 4 days, 14 days), respectively. The changes in the expression of cAMP response element binding protein (CREB) and calcitonin gene-related peptide (CGRP) were detected by immunohistochemistry and computer image analysis methods. The results showed that compared with the normal group, the expressions of CREB in the hippocampal CA1 region increased significantly in the HS, HS/IR and IR groups ( < 0.05). Compared to the normal group, heat stress could result in CGRP excretion and redistribution in the cerebrum, with the highest level in the 4 d HS/IR group. Following heat stress, CGRP immunoreactivity was observed in varicose fibers and neuronal perikarya within the CA1 region. The results indicate that heat stress can induce CREB expression, which in turn stimulates CGRP secretion.

关键词： calcitonin gene-related subsequent ischemia/reperfusion computer cerebrum CGRP excretion

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Supplier selection and order splitting in multiple-sourcing inventory systems

WANG Guicong, JIANG Zhaoliang, LI Zhaoqian, LIU Wenping

《机械工程前沿（英文）》 2008年第3卷第1期页码 23-27 doi: 10.1007/s11465-008-0016-3

摘要： Supplier selection and inventory control are critical decision processes in single-item multiple-supplier systems. An integer linear programming model is proposed to help managers determine the reorder level, choose the best suppliers, and place the optimum order quantities so that the total average inventory cost is minimum, and constraints of supplier ability, quality, and demand are considered. An algorithm combining the branch-bound algorithm and enumeration algorithm is developed to solve the problems. Application of the proposed model in an automobile industry shows that it is effective.

关键词： automobile industry branch-bound algorithm selection single-item multiple-supplier effective

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Effects of DNA damage on oocyte meiotic maturation and early embryonic development

Shen YIN,Junyu MA,Wei SHEN

《农业科学与工程前沿（英文）》 2014年第1卷第3期页码 185-190 doi: 10.15302/J-FASE-2014035

摘要： DNA damage is one of the most common threats to meiotic cells. It has the potential to induce infertility and genetic abnormalities that may be passed to the embryo. Here, we reviewed exogenous factors which could induce DNA damage. Specially, we addressed the different effects of DNA damage on mouse oocytes and embryonic development. Complex DNA damage, double-strand breaks, represents a more difficult repair process and involves various repair pathways. Understanding the mechanisms involved in DNA damage responses may improve therapeutic strategies for ovarian cancer and fertility preservation.

关键词： DNA damage double-strand breaks (DSBs) oocyte embryo

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Genomic regions under selection for important traits in domestic horse breeds

Xuexue LIU, Yuehui MA, Lin JIANG

《农业科学与工程前沿（英文）》 2017年第4卷第3期页码 289-294 doi: 10.15302/J-FASE-2017155

摘要： Horses were domesticated 5500 years ago, thousands of years later than other domestic animals; however, in this relatively short period, domestic horses have had a great impact on human history by accelerating civilization, revolutionizing warfare and advancing agricultural production. Modern breeding using marker-assisted selection has greatly accelerated breeding progress. Therefore, identification of genetic markers underlying the traits of interest in domestic horses is the basis for the modern breeding system. In this review, we present an overview of genetic mapping studies and genome wide analyses to identify the genomic regions targeted by positive selection for four important aspects of horses, coat color, racing performance, gait and height at withers. The locus, for example, has been shown to be the main gene responsible for chestnut color, and the locus has been shown to control the muscle fiber growth in racing breeds. The missense mutation in is the causal mutation for the alternate gaits in horses. Height at withers, a quantitative trait, was mapped to four major loci (3:105547002, 6:81481064, 9:75550059 and 11:232597 32) that can explain 83% of the height variations in domestic horses.

关键词： horse coat color racing performance gait height

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Factors affecting early embryonic development in cattle: relevance for bovine cloning

Yanna DANG, Kun ZHANG

《农业科学与工程前沿（英文）》 2019年第6卷第1期页码 33-41 doi: 10.15302/J-FASE-2018228

摘要：

Female infertility represents a major challenge for improving the production efficiency in the dairy industry. Historically, fertility has declined whereas milk yield has increased tremendously due to intensive genetic selection. evidence reveals about 60% pregnancy loss takes place during the first month following fertilization. Meanwhile, early embryo development is significant for somatic cell nuclear transfer in cattle as a large proportion of cloned embryos fail to develop beyond peri-implantation stage. Oocyte quality is of utmost importance for the early embryo to develop to term for both fertilized and cloned embryos. Epigenetic reprogramming is a key process occurring after fertilization and critical roles of epigenetic modifiers during preimplantation development are now clear. Incomplete epigenetic reprogramming is believed to be a major limitation to cloning efficiency. Treatment of cloned embryos with epigenetic modifying drugs (e.g., Trichostatin A) could greatly improve cloning efficiency in both mice and cattle. Recently, the rapid progress in high-throughput sequencing technologies has enabled detailed deciphering of the molecular mechanisms underlying these events. The robust efficiency of genomic editing tools also presents an alternative approach to the functional annotation of genes critical to early development.

关键词： bovine cloning embryo development somatic cell nuclear transfer X-inactive specific transcript