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STAT1 signaling is required for optimal Th1 cell differentiation in mice

Chinese Science Bulletin 2010年第11期55卷 1032-1040页

作者： ma Da huaNG hua huaNG Zan The Key Laboratory of Developmental Genes and Human Disease of Education Ministry School of Basic Medical Science Southeast University Nanjing 210009 China Department of Cell Biology Neurology and Anatomy Stritch School of Medicine Loyola University Chicago Maywood IL 60153 USA

Although IFN-γ alone does not prime type I T helper cell (Th1) differentiation, the loss of IFN-γ signaling leads to impaired Th1 phenotype: IFN-γ receptor-deficient (Ifngr-/-) Th1 cells fail to permanently repress IL-4 expression. They can differentiate into IL-4-producing cells under Th2-inducing conditions. These observations suggest that IFN-γ signaling plays a critical role in si- lencing Il4 gene in Th1 cells and stabilizing Th1 phenotype. IFN-γ signaling has been further shown to inhibit IL-4 expression by inhibiting STAT6 phosphorylation. This work aims to study the mechanism by which STAT1, the downstream molecule that transduces IFN-γ signaling, may mediate suppression of IL-4 expression in Th1 cells. The results show that STAT1-deficient naive CD4+ T cells express a reduced level of IFN-γ as well as an elevated level of IL-4. These cells exhibit bias to differentiate into Th2 cells under unpolarized conditions. Under Th1-inducing conditions, STAT1-deficient naive CD4+ T cells show impaired Th1 differentiation: Stat1-/- Th1 cells express reduced levels of IFN-γ and T-bet. These cells also fail to repress the expression of IL-4 and GATA-3 and retain STAT6 signaling. More importantly, Stat1-/- Th1 cells can be effectively induced to differentiate into IL-4-producing cells under Th2-inducing conditions. Ectopic expression of T-bet in Stat1-/- Th1 cells dramatically represses their ability to do so and drastically restores IFN-γ expression, suggesting that STAT1 may inhibit IL-4 expression through T-bet. Finally, histone H3 acetylation (H3AC) and histone H3 K4 dimethylation (H3K4dim) were observed in two enhancer regions of Il4 gene locus in Stat1-/- Th1 cells, suggesting a permissive status of Il4 gene locus in these cells. Thus, this study reveals new mechanisms by which STAT1 signaling may mediate repression of Il4 gene in Th1 cells: upregulating T-bet that subsequently represses GATA3 and IL-4 expression, antagonizing STAT6 signaling, and inhibiting epigen

关键词： STAT1 Th1/Th2 房间 T 赌注 STAT6 信号 transduction

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Genetic diagnosis of neonatal-onset seizures

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Genes & Diseases 2019年第4期6卷 441-447页

作者： Xueling ma Fengzhu Yang Ziyu hua The Department of Neonatology Children’s Hospital of Chongqing Medical UniversityChongqing400014China Ministry of Education Key Laboratory of Child Development and Disorders Chongqing400014China Chongqing International Science and Technology Cooperation Center for Child Development and Disorders Chongqing400014China Chongqing Key Laboratory of Child Infection and Immunity Chongqing400014China National Demonstration Base of Standardized Training Base for Resident Physicians Chongqing400014China

many seizures in neonates are due to early-onset epilepsy,which is often difficult to diagnose,especially to explore the ***,the development of next-generation sequencing(NGS)has led to the discovery of a large number of genes involved in *** may improve prompt detection of early-onset epilepsy in *** study aimed at analyzing the genotype-phenotype correlations in neonates with seizures in a bid to improve the understanding of genetic diagnosis of early-onset *** features and prognosis of 15 children who underwent genetic testing having had unexplained seizures from February 2016 to may 2018 in Children’s Hospital of Chongqing Medical University were analyzed *** salient findings were:poor response to stimulus and abnormal electroencephalogram(EEG)in the initial period were observed in the group with concomitant genetic *** the recent progress in genetic technology,molecular diagnosis for neonatal-onset epilepsy can be challenging due to genetic and phenotypic ***,some genotypes are associated with specific clinical manifestations and EEG ***,in-depth understanding of genotype-phenotype correlations would be useful to clinicians managing neonates with early-onset seizures.

关键词： Genetic Genotype-phenotype Molecular diagnosis Neonate Seizures

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Object recognition and pose estimation using appearance manifolds

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Advances in manufacturing 2013年第3期1卷 258-264页

作者： Zhong-hua Hao Shi-Wei ma School of Mechatromc Engineering and Automation Key Laboratory of Power Station Automation Technology Shanghai University

Conventionally, image object recognition and pose estimation are two independent components in machine vision. This paper presented a simple but effective method KNNSNG, which tightly couples these two com ponents within a single algorithm framework. The basic idea of this method came from the bionic pattern recog nition and the manifold ways of perception. Firstly, the shortest neighborhood graphs （SNG） are established for each registered object. SNG can be regarded as a covering and triangulation for a hypersurface on which the training data are distributed. Then for recognition task, the deter mined test image lies on which SNG by employing the parameter ＂k＂, which can be calculated adaptively. Finally, the local linear approximation method is adopted to build a local map between highdimensional image space and lowdimensional manifold for pose estimation. The projective coordinates on manifold can depict the pose of object. Experiment results manifested the effectiveness of the method.

关键词： Object recognition Pose estimation -manifold

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Ballistic impact response of resistance-spot-welded(RSW) double-layered plates for Q&P980 steel

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Defence Technology（防务技术） 2022年第6期18卷 1052-1064页

作者： Bo-han ma Dong-fang ma huan-ran Wang Da-nian Chen Feng-hua Zhou MOE Key Laboratory of Impact and Safety Engineering Ningbo UniversityNingbo315211China College of Science&Technology Ningbo UniversityNingbo315211China

Ballistic impact response of resistance-spot-welded(RSW)double-layered(2×1.6 mm)plates(190 mm×150 mm)for Q&P980 steel impacted by a round-nosed steel bullet(12 mm diameter and 30 mm length)was investigated by using gas gun and high-speed camera *** RSW specimens were spot welded using a 6 mm diameter electrode face producing a 7.2 mm diameter fusion zone of the spot *** ballistic curve and energy balance for the tests of the spot weld of the RSW specimens at different velocity were analyzed to characterize the ballistic behavior of the RSW specimens under bullet *** fracture mechanisms of the RSW specimens under bullet impact were *** the tests below the ballistic limit,the cracks initiated from the notch-tip and propagated along the faying surface or obliquely through the thickness depending on the impact *** the tests above the ballistic limit,the plug fracture in the front plate of the RSW specimen could be caused by the thinning-induced necking in the BM near the HAZ,while the plug fracture in the rear plate of the RSW specimens may be consist of the circumferential cracking from the rear surface and the bending fracture of the hinged part of *** effects of the electrode indentation and the weld interfaces on deformation and fracture of the RSW specimens under bullet impact were *** the tests above the ballistic limit,the circumferential fracture from the rear surface of the RSW specimens was always initiated along the interior periphery of the electrode indentation and the crack paths were along the FZ/CGHAZ or CGHAZ/FGHAZ *** the circumferential crack also formed outside the electrode indentation,the fracture on the BM/HAZ interface could be *** the front plate of the RSW specimens,the shear/bending induced cracking from the notch-tip were observed and the crack paths were along the FZ/CGHAZ or CGHAZ/FGHAZ interface.

关键词： RSW Q&P980 steel Ballistic impact Deformation Fracture

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Process Analysis of In-situ Strain during the M_s8.0 Wenchuan Earthquake—Data from the Stress Monitoring Station at Shandan

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Acta Geologica Sinica(English Edition) 2009年第4期83卷 754-766页

作者： PENG hua.ma Xiumin JIANG Jingjie Key Lab of Neotectonic Movement and Geohazards Ministry of Land and Resources Beijing 100081 China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China

There were huge life and property losses during the Ms8.0 Wenchuan earthquake on may 12, 2008. Strain fluctuation curves were completely recorded at stress observatory stations in the Qinghai-Tibet plateau and its surroundings in the process of the earthquake. This paper introduces the geological background of the Wenchuan earthquake and the profile of in-situ stress monitoring stations. In particular, data of 174 earthquakes （Ms4.0-Ms8.5） were processed and analyzed with various methods, which were recorded at the Shandan station from August 2007 to December 2008. The results were compared with other seismic data, and further analyses were done for the recoded strain seismic waves, co-seismic strain stepovers, pre-earthquake strain valleys, Earth＇s free oscillations before and after the earthquake and their physical implications. During the Wenchuan earthquake, the strainmeter recorded a huge extensional strain of 70 seconds, which shows that the Wenchuan earthquake is a rupture process predominated by thrusting. Significant precursory strain anomalies were detected 48 hours, 30 hours, 8 hours and 37 minutes before the earthquake. The anomalies are very high and their forms are very similar to that of the main shock. Similar anomalies can also be found in strain curves of other shocks greater than Ms7.0, indicating that such anomalies are prevalent before a great earthquake. In this paper, it is shown that medium aftershocks （Ms5.5- 6.0） can also cause Earth＇s free oscillations. Study of free oscillations is of great significance to understand the internal structure of the Earth and focal mechanisms of earthquakes and to recognize slow shocks, thus providing a scientific basis for the prevention and treatment of geological disasters and the prediction of future earthquakes.

关键词： Wenchuan earthquake volume strainmeter Earth's free oscillation in-situ stress

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Biological control of aflatoxin contamination of crops

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第10期9卷 787-792页

作者： Yan-ni YIN Lei-yan YAN Jin-hua JIANG Zhong-hua.ma Institute of Biotechnology Zhejiang University Hangzhou 310029 China

Aflatoxins produced primarily by two closely related fungi, Aspergillus flavus and Aspergillus parasiticus, are mutagenic and carcinogenic in animals and humans. Of many approaches investigated to manage aflatoxin contamination, bio-logical control method has shown great promise. Numerous organisms, including bacteria, yeasts and nontoxigenic fungal strains of A. flavus and A. parasiticus, have been tested for their ability in controlling aflatoxin contamination. Great successes in reducing aflatoxin contamination have been achieved by application of nontoxigenic strains of A. flavus and A. parasiticus in fields of cotton, peanut, maize and pistachio. The nontoxigenic strains applied to soil occupy the same niches as the natural occurring toxigenic strains. They, therefore, are capable of competing and displacing toxigenic strains. In this paper, we review recent development in biological control of aflatoxin contamination.

关键词： Aflatoxin Aspergillus Biocontrol Food safety

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Expression patterns of OCT4, NANOG, and SOX2 in goat preimplantation embryos from in vivo and in vitro

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Journal of Integrative Agriculture 2015年第7期14卷 1398-1406页

作者： YU Xiao-li ZHAO Xiao-e WANG hua-yan ma Bao-hua College of Veterinary Medicine Northwest A&F University Key Laboratory of Animal Biotechnology Ministry of Agriculture

The transcription factors, including OCT4, NANOG, and SOX2, played crucial roles in the maintenance of self-renewal and pluripotency in embryonic stem cells （ESCs）. They expressed in preimplantation mammalian development with spa- tio-temporal pattern and took part in regulation of development. However, their expression and roles in goat had not been reported. In the present study, the expression of OCT4, NANOG, and SOX2 in goat preimplantation embryos both in vivo and in vitro were detected by real-time RCR and immunofluorescence. For in vivo fertilized embryos, the transcripts of OCT4, NANOG, and SOX2 could be detected from oocytes to blastocyst stage, their expression in morula and blastocyst stages was much higher than other stage. OCT4 protein was detected from oocyte to blastocyst, but the fluorescence was more located-intensive with nuclei from 8-cell stage, its expression present in both inner cell mass （ICM） and trophoblast cells （TE） at blastocyse stage. NANOG protein was similar to OCT4, the signaling of fluorescence completely focused on cell nuclei, while the SOX2 firstly showed nuclei location in morula. Comparing to in vivo fertilized embryo, the mRNA of these three transcription factors could be detected at 8-cell stage in parthenogenetic embryos （in vitro）. Thereafter, the expressional level rose gradually along with embryo development. The locations of OCT4 and NANOG proteins were similar to in vivo fertilized embryos, and they located in cell nuclei from morula to blastocyst stage, while SOX2 protein firstly could be detected in cell nuclei at 8-cell stage. These differences suggested that OCT4, NANOG, and SOX2 played different function in regulating development of goat preimplantation embryos. These results may provide a novel insight to goat embryo development and be useful for goat ESCs isolation.

关键词： goat OCT4 NANOG SOX2 embryo expression pattern

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基于改进人工神经网络的多指标冷鲜羊肉新鲜度无损检测

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光谱学与光谱分析 2025年第1期45卷 291-300页

作者：徐子洋姜新华翟成珺马学磊李靖内蒙古农业大学计算机与信息工程学院内蒙古呼和浩特010018 内蒙古自治区农牧业大数据研究与应用重点实验室内蒙古呼和浩特010018 内蒙古自治区教育考试院内蒙古呼和浩特010018

冷鲜羊肉新鲜度受多种因素影响,可通过多个理化和微生物指标综合评价。传统检测方法操作复杂、效率低。高光谱成像作为一种快速且非破坏性的检测技术,可以有效地检测冷鲜羊肉新鲜度改变过程中不同成分的变化。为了研究采用高光谱成像技... 详细信息

冷鲜羊肉新鲜度受多种因素影响,可通过多个理化和微生物指标综合评价。传统检测方法操作复杂、效率低。高光谱成像作为一种快速且非破坏性的检测技术,可以有效地检测冷鲜羊肉新鲜度改变过程中不同成分的变化。为了研究采用高光谱成像技术实现冷鲜羊肉新鲜度多指标评价的可行性,提出一种改进人工神经网络算法,通过重新定义损失函数加强标记之间的相关性,充分采用多个新鲜度指标对冷鲜羊肉新鲜度分类。试验收集了0~14 d冷鲜羊肉样本在400~1000 nm范围的高光谱图像,采用实验室方法测定挥发性盐基氮(TVB-N)、pH值、菌落总数(TAC)和大肠菌群近似数(ANC)指标值。通过S-G平滑滤波法和多元散射校正对冷鲜羊肉样本原始光谱数据进行预处理,采用连续投影法(SPA)选择光谱数据的18个特征波长作为输入数据,采用所提出的改进人工神经网络算法建立多指标冷鲜羊肉新鲜度等级模型。结果表明,改进人工神经网络对测试集的分类准确率达96%,三个新鲜度等级样本的识别率分别为100%、89.28%和98.68%,采用汉明损失(hamming loss)、1-错误率(one-error)、排序损失(ranking loss)和覆盖率(coverage)四种多标记模型指标进行评价,评价指标分别为0.008、0.002、0.0025和4.048。改进人工神经网络分类模型的准确率和各项模型评价指标均优于传统ANN,证明改进人工神经网络用于多指标冷鲜羊肉新鲜度的无损检测具有可行性。

关键词：无损检测高光谱神经网络多指标分类

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Vegetative Proliferation and Secondary Proliferated Inflorescences Development in Grass

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Journal of Integrative Plant Biology 2006年第11期48卷 1306-1311页

作者： Guo-hua.ma Xue-Lin huang Bunn Eric South China Botanical Garden the Chinese Academy of Sciences Guangzhou 510650 China College of Life Sciences Zhongshan University Guangzhou 510275 China Kings Park and Botanic Garden West Perth WA 6005 Australia

We report the vegetative proliferation and new phenomenon of ＂secondary proliferated inflorescences＂ In the grass Ischaemum barbatum Retz, as determined by anatomical analysis of prepared sections of inflorescences. Leaves and shoots could be developed from the original splkelets of Inflorescences and plantlets developed when these shoots were transplanted to moist soil. ＂Secondary proliferated Inflorescences＂ is the first name here because some inflorescences that developed inadequacy are grown from the splkelet on the mother Inflorescence. Our investigation showed that this form of vegetative proliferation and secondary proliferated inflorescences development of L barbatum has arisen following late autumn fires of the previous year. It Is suggested that the sudden onset of a fire could lead to a hormone Imbalance or a chemical induction, which results in ephemeral vegetative proliferation even secondary proliferated inflorescences development in wild populations.

关键词： Ischaemum barbatum secondary proliferated inflorescence vegetative proliferation.

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Theoretical analysis on expansion mechanism in carbon dioxide expander

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Science China(Technological Sciences) 2011年第6期54卷 1469-1474页

作者： TIAN hua.ma YiTai LI MinXia ZHANG MeiLan Thermal Energy Research Institute Tianjin UniversiO Tianjin 300072 China

The expansion mechanism inside carbon dioxide expander is analyzed theoretically in this *** mechanism analysis of metastable equilibrium indicates that there is a potential barrier during phase change *** is to say energy is required to overcome the potential barrier when the new interface is formed from primary *** superheat of liquid is the impetus of phase change and has an exponential decrease with the increase of the saturated temperature of *** analysis also indicates that there is a critical radius during the phase change *** bubble will grow up when its radius is larger than the critical value,otherwise,will *** considering the metastable phase change,calculation of P and V during expansion process indicates that the phase-change will be delayed with the decline of pressure,which is called lag *** phase-change delay time decreases with the increase of initial *** the initial temperature is close to the critical temperature,the delay time is close to *** phase-change delay brings energy losses,which decrease with the increase of initial temperature and its decrease ratio also has a decrease *** the initial pressure is 10 MPa,the energy loss will be 1.06 W with an initial temperature of 10℃ while 0.34 W with that of 20℃.

关键词： expansion mechanism carbon dioxide expander potential barrier superheat degree phase-change delay

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