Recrystallization and Microstructural Evolution During Hot Extrusion of Mg97Y2Zn1 Alloy

Bin Chen,Xiaoling Li,Chen Lu,Dongliang Lin 대한금속·재료학회 2014 METALS AND MATERIALS International Vol.20 No.3

This study revealed that the extrusion temperature has a great influence on microstructure and mechanicalproperties of the Mg97Y2Zn1 alloy. The average grain sizes increased from 3 μm to 8 μm with increasingextrusion temperatures from 623K to 773 K. Both dynamic recrystallization (DRX) and static recrystallization(SRX), which occur during and after deformation, respectively, were observed. The alloy, which extrudedat a relatively high temperature, exhibited lower strength because the strain strengthening was balanced bythe softening that originated from DRX. Three types of morphologies, namely, big recrystallized grains, fine recrystallizedgrains, and non-recrystallized grains, were observed in the extruded microstructures obtained at 623 K. The dislocation density was quite high in the fully recrystallized grain. The extruded microstructures obtainedat 773 K were composed of large grains with more uniform size. Their degree of recrystallization was higherand the dislocation density also declined. All dislocation in the grain were distinguished as <c+a> dislocations. Submicron scale precipitates were distributed along the newly formed recrystallized grain boundaries andhad a remarkable pinning effect on the recrystallized grain growth after extrusion at 773 K. The precipitates canbe divided into two main types: mixed type and single type.

Whole Exome Sequencing in the Accurate Diagnosis of Bilateral Breast Cancer: a Case Study

Xiaoling Li,Mei Yang,Qiangzu Zhang,Yanhui Fan,Teng Zhu,Fulong Chen,Kun Wang 한국유방암학회 2019 Journal of breast cancer Vol.22 No.1

When faced with a case of bilateral breast cancer (BBC), understanding how to differentiate bilateral primary breast cancer from contralateral metastatic breast cancer is essential for treatment, but clear identification criteria have not been established to date. Diverse events play different roles in the therapy and prognosis of BBC; hence, it is of great significance to detect a more comprehensive and convincing technique to make an accurate differential diagnosis. We report a rare case of synchronous BBC in a 61-year-old Chinese woman. Based on her clinical and pathological features and the use of whole exome sequencing and cancer genome analysis, we concluded that the patient developed contralateral metastatic breast cancer which metastasized from left to right. Therefore, together with clinical, pathological and cancer genomics information, we could precisely define the origin and evolution of BBC.

An experimental study on the ballistic performance of FRP-steel plates completely penetrated by a hemispherical-nosed projectile

Changhai Chen,Xi Zhu,Hailiang Hou,Lijun Zhang,Xiaole Shen,Ting Tang 국제구조공학회 2014 Steel and Composite Structures, An International J Vol.16 No.3

Experiments were carried out to investigate the ballistic performance of fiber reinforced plastic(FRP)-steel plates completely penetrated by hemispherical-nosed projectiles at sub-ordnance velocities greater than their ballistic limits. The FRP-steel plate consists of a front FRP laminate and a steel backing plate. Failure mechanisms and impact energy absorptions of FRP-steel plates were analyzed and compared with FRP laminates and single steel plates. The effects of relative thickness, manufacturing method and fabric type of front composite armors as well as the joining style between front composite armors and steel backing plates on the total perforation resistance of FRP-steel plates were explored. It is found that in the case of FRP-steel plates completely penetrated by hemispherical-nosed projectiles at low velocities, the failure modes of front composite armors are slightly changed while for steel backing plates, the dominate failure modes are greatly changed due to the influence of front composite armors. The relative thickness and fabric type of front composite armors as well as the joining style of FRP-steel plates have large effects whereas the manufacturing method of front composite armors has slight effect on the total perforation resistance of FRP-steel plates.

Two Evaluation Budgets for the Measurement Uncertainty of Glucose in Clinical Chemistry

Hui Chen,Ling Zhang,Xiaoyun Bi,Xiaoling Deng 대한진단검사의학회 2011 Annals of Laboratory Medicine Vol.31 No.3

Background: Measurement uncertainty characterizes the dispersion of the quantity values attributed to a measurand. Although this concept was introduced to medical laboratories some years ago, not all medical researchers are familiar with it. Therefore, the evaluation and expression of measurement uncertainty must be highlighted using a practical example. Methods: In accordance with the procedure for evaluating and expressing uncertainty, provided by the Joint Committee for Guides in Metrology (JCGM), we used plasma glucose (Glu) as an example and defined it as the measurand. We then analyzed the main sources of uncertainty, evaluated each component of uncertainty, and calculated the combined uncertainty and expanded uncertainty with 2 budgets for single measurements and continuous monitoring, respectively. Results: During the measurement of Glu, the main sources of uncertainty included imprecision, within-subject biological variance (BVw), calibrator uncertainty, and systematic bias. We evaluated the uncertainty of each component to be 1.26%, 1.91%, 5.70%, 0.42%, and -2.87% for within-run imprecision, between-day imprecision, BVw, calibrator uncertainty, and systematic bias, respectively. For a single specimen, the expanded uncertainty was 7.38% or 6.1±0.45 mmol/L (κ=2); in continuous monitoring of Glu, the expanded uncertainty was 13.58% or 6.1±0.83 mmol/L (κ=2). Conclusions: We have demonstrated the overall procedure for evaluating and reporting uncertainty with 2 different budgets. The uncertainty is not only related to the medical laboratory in which the measurement is undertaken, but is also associated with the calibrator uncertainty and the biological variation of the subject. Therefore, it is helpful in explaining the accuracy of test results. Background: Measurement uncertainty characterizes the dispersion of the quantity values attributed to a measurand. Although this concept was introduced to medical laboratories some years ago, not all medical researchers are familiar with it. Therefore, the evaluation and expression of measurement uncertainty must be highlighted using a practical example. Methods: In accordance with the procedure for evaluating and expressing uncertainty, provided by the Joint Committee for Guides in Metrology (JCGM), we used plasma glucose (Glu) as an example and defined it as the measurand. We then analyzed the main sources of uncertainty, evaluated each component of uncertainty, and calculated the combined uncertainty and expanded uncertainty with 2 budgets for single measurements and continuous monitoring, respectively. Results: During the measurement of Glu, the main sources of uncertainty included imprecision, within-subject biological variance (BVw), calibrator uncertainty, and systematic bias. We evaluated the uncertainty of each component to be 1.26%, 1.91%, 5.70%, 0.42%, and -2.87% for within-run imprecision, between-day imprecision, BVw, calibrator uncertainty, and systematic bias, respectively. For a single specimen, the expanded uncertainty was 7.38% or 6.1±0.45 mmol/L (κ=2); in continuous monitoring of Glu, the expanded uncertainty was 13.58% or 6.1±0.83 mmol/L (κ=2). Conclusions: We have demonstrated the overall procedure for evaluating and reporting uncertainty with 2 different budgets. The uncertainty is not only related to the medical laboratory in which the measurement is undertaken, but is also associated with the calibrator uncertainty and the biological variation of the subject. Therefore, it is helpful in explaining the accuracy of test results.

Probabilistic Risk Assessment of RCC Dam Considering Grey-Stochastic-Fuzzy Uncertainty

Wenlong Chen,Xiaoling Wang,Minghui Liu,Yushan Zhu,Shaohui Deng 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.11

Greyness, randomness and fuzziness are three inseparable uncertainty factors influencing the safety of a roller compacted concrete dam (RCC dam), which can be regarded as a system reliability problem associated with multiple failure modes. Aiming at the current probabilistic risk analysis of RCC dams, most of the studies limited to single failure mode and single uncertainty. A probabilistic risk assessment method for dam under Grey-Stochastic-Fuzzy (GSF) uncertainty is proposed to consider the randomness and greyness of parameters and the fuzziness of the failure criteria. First, the fault tree model of an RCC dam is established based on Fault Tree Analysis (FTA). Then, bootstrap repeated sampling is embedded into grey system theory to quantify the grey properties of stochastic variables. The Latin Hypercube Sampling (LHS) function is improved to compensate for the inability of describing the fuzzy failure criteria. Finally, considering the correlated multiple failure modes, the proposed method is applied to analyze the parameter sensitivity and failure probability of the LDL dam in China. The results show that the proposed method is a high-efficiency, fastconvergence and more scientific method with reasonable outputs compared to common uncertainty probability analysis methods. The proposed method also provides an effective basis for the structural design and safety analysis of a concrete dam.

Genome-wide analysis and environmental response profiling of dirigent family genes in rice (Oryza sativa)

Rongjun Chen,Yongrong Liao,Shengbin Liu,Yunyun Jiang,Changqiong Hu,Xuewei Zhang,Xufeng Cao,Zhengjun Xu,Xiaoling Gao,Lihua Li,Jianqing Zhu 한국유전학회 2017 Genes & Genomics Vol.39 No.1

Dirigent (DIR) and DIR-like family genes were involved in lignification or in the response to pathogen infection and abiotic stress in plants. Little is known to us about how rice DIR genes respond to adverse conditions. In this study, we reported genome-wide analysis of 49 DIR or DIR-likes genes in rice. The 49 OsDIRs or OsDIR-likes were tandem arranged into ten clusters. The phylogenetic analysis indicated that the 49 rice DIR and DIR-like genes cluster into five distinct subfamilies, DIR-a and four DIRlike subfamilies (DIR-b/d, and DIR-g, DIR-c, DIR-e). Meta-analysis of microarray gene expression datas indicated that all the OsDIRs or OsDIR-likes were expressed almost at the same level but with different patterns: most OsDIRs or OsDIR-likes were expressed exclusively in stigma and ovary and were induced by IAA and BAP; several genes were induced by trans-zeatin (tZ) and DMSO; 23 OsDIRs or OsDIR-likes were responded to abiotic stress. Our analysis also showed that most of these genes could respond to abiotic stresses, which contained cis-regulatory elements. The present study will provide a useful reference for further functional analysis of the DIR genes in rice.

Maternal undernutrition alters the skeletal muscle development and methylation of myogenic factors in goat offspring

Zhou Xiaoling,Yan Qiongxian,Liu Liling,Chen Genyuan,Tang Shaoxun,He Zhixiong,Tan Zhiliang 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.6

Objective: The effects of maternal undernutrition during midgestation on muscle fiber histology, myosin heavy chain (MyHC) expression, methylation modification of myogenic factors, and the mammalian target of rapamycin (mTOR) signaling pathway in the skeletal muscles of prenatal and postnatal goats were examined. Methods: Twenty-four pregnant goats were assigned to a control (100% of the nutrients requirement, n = 12) or a restricted group (60% of the nutrients requirement, n = 12) between 45 and 100 days of gestation. Descendants were harvested at day 100 of gestation and at day 90 after birth to collect the femoris muscle tissue. Results: Maternal undernutrition increased (p<0.05) the fiber area of the vastus muscle in the fetuses and enhanced (p<0.01) the proportions of MyHCI and MyHCIIA fibers in offspring, while the proportion of MyHCIIX fibers was decreased (p<0.01). DNA methylation at the +530 cytosine-guanine dinucleotide (CpG) site of the myogenic factor 5 (MYF5) promoter in restricted fetuses was increased (p<0.05), but the methylation of the MYF5 gene at the +274,280 CpG site and of the myogenic differentiation (MYOD) gene at the +252 CpG site in restricted kids was reduced (p<0.05). mTOR protein signals were downregulated (p<0.05) in the restricted offspring. Conclusion: Maternal undernutrition altered the muscle fiber type in offspring, but its relationship with methylation in the promoter regions of myogenic genes needs to be elucidated. Objective: The effects of maternal undernutrition during midgestation on muscle fiber histology, myosin heavy chain (MyHC) expression, methylation modification of myogenic factors, and the mammalian target of rapamycin (mTOR) signaling pathway in the skeletal muscles of prenatal and postnatal goats were examined.Methods: Twenty-four pregnant goats were assigned to a control (100% of the nutrients requirement, n = 12) or a restricted group (60% of the nutrients requirement, n = 12) between 45 and 100 days of gestation. Descendants were harvested at day 100 of gestation and at day 90 after birth to collect the femoris muscle tissue.Results: Maternal undernutrition increased (p<0.05) the fiber area of the vastus muscle in the fetuses and enhanced (p<0.01) the proportions of MyHCI and MyHCIIA fibers in offspring, while the proportion of MyHCIIX fibers was decreased (p<0.01). DNA methylation at the +530 cytosine-guanine dinucleotide (CpG) site of the myogenic factor 5 (MYF5) promoter in restricted fetuses was increased (p<0.05), but the methylation of the MYF5 gene at the +274,280 CpG site and of the myogenic differentiation (MYOD) gene at the +252 CpG site in restricted kids was reduced (p<0.05). mTOR protein signals were downregulated (p<0.05) in the restricted offspring.Conclusion: Maternal undernutrition altered the muscle fiber type in offspring, but its relationship with methylation in the promoter regions of myogenic genes needs to be elucidated.

Genome-wide analysis and environmental response profiling of SOT family genes in rice (Oryza sativa)

Rongjun Chen,Yunyun Jiang,Jiali Dong,Xin Zhang,Hongbo Xiao,Zhengjun Xu,Xiaoling Gao 한국유전학회 2012 Genes & Genomics Vol.34 No.5

Sulphotransferase (SOT) catalyses the transfer of a sulphonate group from 3'-phosphoadenosine 5'-phosphosulphate (PAPS)to an appropriate hydroxyl group of various substrates with the parallel formation of 3'-phosphoadenosine 5'-phosphate (PAP). Although several SOTs have been identified and characterized in mammalian, their role in plant is still unclear. In this study, we report genome-wide comprehensive expression analysis of 35 putative SOT genes in rice. The 35 OsSOTs were tandemly arranged into six clusters. The phylogenetic analysis showed that there were 7 subfamilies of OsSOTs and 11 putatively conserved motifs. Six OsSOTs might be pseudogenes,25 have the two motifs which were involved in PAPS binding regions I and IV. Microarray data indicated that all the OsSOTs were expressed almost at the same level but with different patterns: most OsSOTs were expressed exclusively in stigma and ovary and induced by IAA and BAP, several genes were induced by tZ and DMSO and 11 OsSOTs were response to abiotic stress. Further analysis showed that these 11 genes contained cis-regulatory elements responding to abiotic stresses.

Exploring the Metabolomic Responses of Bacillus licheniformis to Temperature Stress by Gas Chromatography/Mass Spectrometry

( Zixing Dong ),( Xiaoling Chen ),( Ke Cai ),( Zhixin Chen ),( Hongbin Wang ),( Peng Jin ),( Xiaoguang Liu ),( Kugenthiren Permaul ),( Suren Singh ),( Zhengxiang Wang ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.3

Owing to its high protein secretion capacity, simple nutritional requirements, and GRAS (generally regarded as safe) status, Bacillus licheniformis is widely used as a host for the industrial production of enzymes, antibiotics, and peptides. However, as compared with its close relative Bacillus subtilis, little is known about the physiology and stress responses of B. licheniformis. To explore its temperature-stress metabolome, B. licheniformis strains ATCC 14580 and B186, with respective optimal growth temperatures of 42℃ and 50℃, were cultured at 42℃, 50℃, and 60℃ and their corresponding metabolic profiles were determined by gas chromatography/mass spectrometry and multivariate statistical analyses. It was found that with increased growth temperatures, the two B. licheniformis strains displayed elevated cellular levels of proline, glutamate, lysine, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, and octadecanoic acid, and decreased levels of glutamine and octadecenoic acid. Regulation of amino acid and fatty acid metabolism is likely to be associated with the evolution of protective biochemical mechanisms of B. licheniformis. Our results will help to optimize the industrial use of B. licheniformis and other important Bacillus species.

Transcriptome explores changes in gene expression profile contributed by Camellia sinensis (L.) in Apis cerana cerana and Apis mellifera ligustica

Zhao Dongxu,Chen Daoyin,Su Xiaoling,Zhang Xiaojun,Liu Yanjie 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.3

Camellia sinensis (L.) is widely cultivated in China and other countries as an economically important tree and supplies unique nutrients to ensure the development of Apis cerana cerana and Apis mellifera ligustica colonies in early spring in southern China. A. c. cerana was domesticated in China many years ago and exhibits a smaller body size, smaller colony size and some distinct physiology and behavior compared to A. m. ligustica. Here, to explore the changes in gene expression induced by C. sinensis in A. c. cerana and A.m. ligustica, we performed transcriptomic analysis of the 1 st -instar, 5 th -instar, 1 st -adult and 7 th -adult stages of the two species fed the nectar and pollen of C. sinensis. A total of 489, 1190, 991 and 243 differentially expressed genes (DEGs) were identified in the four developmental stages of A. m. ligustica, and 995, 2785, 1513 and 213 DEGs were found in the cor responding stages of A. c. cerana. The changes in the gene expression profile were more significant in the 5 th -instar and 1 st -adult. Furthermore, the upregulated genes in the 5 th -instar and 1 st -adult were mainly enriched in pathways involved in growth- and development-related pathway: Hippo signaling pathway. In addition to the upregulated DEGs, growth- and development-related pathways, including the Wnt signaling pathway, Hedgehog signaling pathway-fly, and FoxO signaling pathway, were enriched in A. c. cerana. Finally, we hypothesized that C. sinensis pollen is beneficial to the growth and development of honeybees and give rise to diverse corresponding regulation to A. c. cerana than to A. m. ligustica.