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携带矮小和卷羽性状鸡的耐热和生产性能分析

携带矮小和卷羽性状鸡的耐热和生产性能分析

作者： ali hassan Nawaz 广东海洋大学

学位级别：硕士

热应激对肉鸡饲养行业具有重要的影响,它会导致肉鸡生产力下降,降低养殖效益。随着全球气候变暖速度逐年攀升,特别是热带地区的环境温度升高,会对肉鸡肌肉发育、免疫和肉质产生有害影响。一些地方鸡品种具有体型矮小和卷羽性状,这被认... 详细信息

热应激对肉鸡饲养行业具有重要的影响,它会导致肉鸡生产力下降,降低养殖效益。随着全球气候变暖速度逐年攀升,特别是热带地区的环境温度升高,会对肉鸡肌肉发育、免疫和肉质产生有害影响。一些地方鸡品种具有体型矮小和卷羽性状,这被认为与耐热性有关。鸡矮小和卷羽性状分别由GHR和KRT75L4基因突变引起。本研究首先分析中国4个地方鸡品系的这两种性状(矮小和卷羽)的遗传突变,包括矮脚黄鸡,麒麟鸡,垌中矮脚鸡和垌中高脚鸡。在此基础上,开展杂交试验,获得具有矮小和卷羽特征的F1代个体,进一步开展热应激试验,对比具有矮小性状和卷羽性状鸡的耐热性能。为培育适合热带地区养殖的肉鸡新品系奠定基础。本研究首先以中国4个地方鸡品种(矮脚黄鸡,麒麟鸡,垌中矮脚鸡和垌中高脚鸡)为研究材料,分析GHR和KRT75L4两个基因的序列信息和遗传变异。提取血液样本DNA,通过PCR和测序的方法对GHR和KRT75L4基因进行基因分型,检测突变位点。结果显示,在矮脚黄鸡GHR基因的外显子9和3′UTR处发现了1.7kb缺失突变。垌中矮脚鸡和垌中高脚鸡的GHR和KRT75L4基因未检测到突变。麒麟鸡的KRT75L4基因外显子2发生了15bp的缺失突变。基于基因分型结果,我们用矮脚黄鸡(雄性)和麒麟鸡(雌性)进行了杂交,获得具有矮小和卷羽特征的F1群体。杂交F1的雌性个体具有半卷羽和矮小的特征。生长发育测定和数据统计分析结果表明,雌性F1杂交鸡群体的体型和生长速度明显减少,且羽毛为半卷羽,介于卷羽和正常羽毛之间。随之,本研究进一步分析了三黄鸡(NYC),矮脚黄鸡(DYC)和杂交F1(Crossbreed)雌性个体的耐热性能。本研究旨在探讨热应激对3个群体的生产性能、组织学、热休克蛋白(HSP70、HSP90)和肌肉生长相关基因(GHR、IGF-1和IGF-1R)的影响。每个品系的72只母鸡在正常环境条件下饲养直到第12周龄。然后随机分为两组(对照组和热应激组),每组有6个重复,每个重复有6只母鸡。在热应激组中,母鸡在35±1°C的高温下每天8小时,持续一周(7天),而在对照组中,母鸡在28±1°C下饲养。在热应激结束时,统计分析体重、采食量的变化;采集肝脏和脾脏组织制作切片,分析组织损伤情况;q RT-PCR分析HSP70等基因的表达变化。结果表明,与对照组相比7天的热应激降低了3个鸡群体的采食量(FI)和体重增量(WGR)。在三个群体都中观察到体重发育显著降低(P0.05)。此外,热应激导致所有鸡群体胸肌中HSP70和HSP90的m RNA表达均显著增加,但肝脏和下丘脑组织中HSP90的m RNA表达没有显著增加(P0.05)。总之,这些结果表明,高温环境对三黄鸡的影响比矮小鸡和杂交群体更严重,这表明矮小和卷羽性状在鸡耐热性中的重要作用。本研究为培育耐热型肉鸡新品种(系)奠定了理论基础。

关键词：鸡热应激矮小卷羽基因分型杂交产肉性能

中国对非洲国家经济发展的贡献探索 ——以坦桑尼亚为例

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中国对非洲国家经济发展的贡献探索 ——以坦桑尼亚为例

作者： ali hassan HAJI 吉林大学

学位级别：硕士

本文阐释了中国在促进非洲国家经济增长方面的贡献,即中国如何在贸易、铁路和公路等基础设施建设、能力建设和外国直接投资等经济问题上帮助非洲。非洲基础设施差,如公路和铁路系统糟糕,不仅影响非洲国家经济活动甚至影响非洲国家GDP,... 详细信息

本文阐释了中国在促进非洲国家经济增长方面的贡献,即中国如何在贸易、铁路和公路等基础设施建设、能力建设和外国直接投资等经济问题上帮助非洲。非洲基础设施差,如公路和铁路系统糟糕,不仅影响非洲国家经济活动甚至影响非洲国家GDP,同时因为一些非洲领导人腐败,缺乏经济规划,在利用资源方面缺乏良好的治理,导致非洲经济遭受巨大挑战。即便如此,中国是非洲国家的重要合作伙伴。非洲计划到2050年国内生产总值达到29万亿美元,中国作为非洲唯一的真正的朋友,不同于利用贷款条件剥削非洲的新殖民主义国家,中国一贯采取双赢行动,中国不给非洲“鱼”但却教授如何得到一条“鱼”的方式,作为战斗依赖问题的解决方案。中国在非洲国家的经济发展中扮演着不同的角色,中国和非洲之间的进出口贸易活动频繁,如坦桑尼亚向中国出口原材料和不同的作物,比如鳄梨、坚果等。本研究分为五章,以中国对非洲国家坦桑尼亚的经济贡献为例,从不同的经济方面解释两国外交关系如何加强。本文使用“中非关系”概念,原因是西方未能维持非洲经济的解决方案,到20世纪50年代,中国采取了支持非洲国家的外交政策,反对殖民主义和帝国主义,支持消除贫困。本文研究中国在非洲国家,特别是坦桑尼亚的经济发展中发挥了什么作用,还提出了本研究的主要论点,即坦桑尼亚通过基础设施,农业项目和外国直接投资的工业经济区等不同的经济项目提高经济生产力。本研究的意义是加速坦桑尼亚政府在发展坦中两国经济发展,获得更多不同项目和技术改造的对外经济外交机会,收获经济增长的经验增长以及开展更多社会和人道主义合作实践。第一章讨论非洲经济发展的问题。作为本论文的介绍部分将讨论阻碍非洲经济发展的不同挑战。第一,基础设施和教育体系落后。非洲的教育水平和标准非常低,一些州的课程设置良好,实施不力,缺乏良好的治理,缺乏高效的教师,以及教育部门提供积极变革的有利环境较差。由于贫困和基础设施薄弱,许多非洲儿童的教育发展落后,尤其是那些偏远地区。第二,对外援助通过协助非洲国家资助修建道路和学校等重要基础设施项目来实现的,这反过来又为当地人创造了就业机会,这种方式使社会均衡发展。不过,对外援助也有其局限性。一些国家仅仅能使用捐助者提供的资金来满足其基本必需品,这导致对援助的依赖。第三,气候变化和政治不稳定。许多非洲国家难以获得可持续发展,政府无法充分制定计划和执行法律,这始终威胁着非洲的经济发展,阻碍了经济进步。非洲经济的来源于农业部门、贸易活动和人力资源。本章还解释了金融缺口理论的文献综述和错误范式,以及与基础设施发展、贸易合作和发展援助有关的文献。本章节展示了从研究开始到结束的管理流程和研究结构。第二章以中国对非洲经济发展的贡献为背景,从不同的意识形态进行剖析。现实主义强调国家利益和国家的重要性,基于权力和安全。权力一直是国家的直接目的和目标。现实主义者坚信,无政府的国际权力结构是混乱的,各国政府缺乏做出明智决策的信心。自由主义认为政治共同体需要与外交政策相关的尊重和尊严,并同意国家继续作为国际体系统一的形象。马克思主义理论强调阶级斗争的思想,资本主义和工人的关系、利润剩余价值、革命以及工业中无产阶级专政。中国和非洲之间的经济互动分为几个阶段,唐朝到清朝时期从公元700年到1800年,中国人被派往埃及,在肯尼亚沿海城市和桑给巴尔带扩张。工业时代从1800年到1949年,中国掌握了贸易控制权,并废除奴隶贸易。接下来到20世纪80年代,这个时期是值得注意的,因为中国和非洲国家都获得了独立,中国共产党取得了胜利。最后一个阶段是经济合作阶段,从20世纪80年代到最近中国加入并建立了中非经济合作组织。这些阶段解释了两国经济发展的重要性,这与非洲殖民入侵之前的存在联系在一起,这意味着中国在非洲的血液中是与其发展经济关系的重要国家。第三章以“授人以鱼,不如授人以渔”的道理,详细介绍了中非双方在互利共赢的基础上经济相互依存,重启工业建设合作,进行重大投资,实现合作共赢。“授鱼”这是基于如何帮助他人进行能力建设,而不是给它任何援助,结果非洲会因为中国解决了经济问题铺平了道路而变得依赖你。中国人在非洲做生意、做贸易的方式,与西方化的发达资本主义国家相当。尽管如此,它与西方盟友的目标和抱负有很大不同。与西方主导的做法相比,中国更加重视经济基础设施,这也正在成为改变工业投资的关键方面。中国和非洲的合作与各个重要经济领域的发展密切相关:贸易关系、农业投资、商品运输、解决失业问题以及发展铁路、机场、公路、桥梁和港口等基础设施计划。中国的经济支持成为非洲国家国内生产总值(GDP)稳定增长的催化剂。第四章探究中国对非洲经济发展的倡议和协议的问题。中国共产党提出了“一带一路”倡议来巩固中非之间的合作,通过这一倡议中国在非洲开展了不同交通、通讯和能源开发基础设施项目。可以说,中国的“一带一路”倡议

关键词：探索外交贡献经济发展中非中坦中国

Central composite design for optimization and formulation of desulphurization of iron ore concentrate using atmospheric leaching process

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Journal of Iron and Steel Research(International) 2018年第1期25卷 57-64页

作者： ali Mostafavi hassan Rezvanipour Dariush Afzali Tayebeh Shamspur Amir Hajizadehomran Department of Chemistry Shahid Bahonar Universityof Kerman Kerman 84156-83111 Iran Gol-e-Gohar Iron Ore Mining and Industrial Company Sirjan Km 50 of Shiraz road 111/78185 Kerman Iran Department of Environment Institute of Science and HighTechnology and Environmental Sciences GraduateUniversity of Advanced Technology Kerman 76311-33131Iran

Owing to the negative effects of sulphur in iron ore on steelmaking process and environment, a tank leaching process was performed in atmospheric conditions to remove the sulphur from the iron ore concentrate and simultaneously to transform sulphide minerals into useful by-products. To achieve desirable sulphur removal rate and efficiency, central composite design was adopted as a response surface methodology for the optimization and evaluation of the process. A full-quadratic polynomial equation between the sulphur removal and the studied parameters was established to assess the behaviour of sulphur removal as a function of the factors and to predict the results in various conditions. The optimum conditions were obtained based on the variance tests and response surface plots, from which the optimized ranges for each factor resulting in the best response （corresponding to the highest percentage of desulphurization） could be then achieved. The results show that most desirable conditions are atmospheric leaching in 1.39 mol/dm3 nitric acid and 0.88 mol/dm3 sulphuric acid for 47 h. The designed process under the optimized desulphurization conditions was applied to a real iron ore concentrate. More than 75% of the total sulphur was removed via the leaching process. In addition to the desulphurization, the conversion of sulphide-bearing minerals into useful by-products, extraction of valuable metals, and executing the process under atmospheric conditions are the other advantages of the proposed method.

关键词： Desulphurization Iron ore concentrate Sulphide mineral leaching Central composite design Atmosphericleaching process

A Microcalorimetry and Spectroscopy Study on the Interaction of BSA with 2,2′-Bipyridine Octylglycinato Palladium(II) Nitrate

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Acta Biochimica et Biophysica Sinica 2003年第10期35卷 886-890页

作者： MANSOORI-TORSHIZI hassan,ISLAMI-MOGHADDAM Mahbobe,SABOURY ali Akbar Institute of Biochemistry and Biophysics Department of Chemistry Institute of Biochemistry and Biophysics University of Tehran Tehran 14176-14411 Iran Department of Chemistry University of Sistan & Bluchestan Zahedan 98167-45345 Iran University of Sistan & Bluchestan Zahedan 98167-45345 Iran University of Tehran Tehran 14176-14411 Iran

The interaction of bovine serum albumin (BSA) with a new palladium(II) complex [Pd(bpy)(Oct-Gly)]NO 3 (bpy, 2,2′-bipyridine; Oct-Gly, octyl-glycine) was studied by isothermal titration UV-visible spectrophotometry and microcalorimetry in 30 mmol/L Tris buffer, pH 7.0. There is a set of 18 binding sites for this complex on BSA at 300 and 310 K with positive cooperativity in the binding process. The Hill coefficients at 300 and 310 K are 2.2 and 2.4, respectively. The binding of this palladium complex on BSA is endothermic with mean association binding constant of 21.0 and 16.4 (mmol/L) -1 at 300 and 310 K, respectively. The complex can denature the protein as surfactants. The stability of BSA in the interaction study with the complex is 84 and 58 kJ/mol at 300 and 310 K, respectively. Also, the enthalpy of BSA denaturation due to the interaction with the complex is 842 kJ/mol.

关键词： serum albumin palladium complex isothermal titration microcalorimetry spectrophotometry

Simultaneous determination of cysteamine and folic acid in pharmaceutical and biological samples using modified multiwall carbon nanotube paste electrode

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Chinese Chemical Letters 2012年第2期23卷 237-240页

作者： ali Taherkhani hassan Karimi-Maleh ali A.Ensafi Hadi Beitollahi Ahmad Hosseini Mohammad A.Khalilzadeh hassan Bagheri Department of Physics Takestan Branchlslamic Azad UniversityTakestanlran Department of Chemistry Majlesi BranchIslamic Azad UniversityIsfahanIran Environment Department Research Institute of Environmental SciencesInternational Center for ScienceHigh Technology and Environmental SciencesKermanIran Department of Chemistry Qaemshahr BranchIslamic Azad UniversityQaemshahrlran Department of Chemistry Takestan Branchlslamic Azad UniversityTakestanlran

A carbon paste electrode（CPE） chemically modified with multiwall carbon nanotubes and ferrocene（FC） was used as a selective electrochemical sensor for the simultaneous determination of trace amounts of cysteamine（CA） and folic acid（FA）.This modified electrode showed very efficient electrocatalytic activity for the anodic oxidation of *** peak current of differential pulse voltammograms of CA and FA increased linearly with their concentration in the ranges of 0.7-200μmol/L CA and 5.0- 700μmol/L *** detection limits for CA and FA were 0.3μmol/L and 2.0μmoI/L,*** diffusion coefficient（D） and transfer coefficient（α） of CA were also *** conditions are sufficient to allow determination of CA and FA both individually and simultaneously.

关键词： Cysteamine Folic acid Carbon nanotube paste electrode Voltammetry

Microstructural analyses of aluminum–magnesium–silicon alloys welded by pulsed Nd: YAG laser welding

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International Journal of Minerals,Metallurgy and Materials 2020年第5期27卷 660-668页

作者： Hossain Ebrahimzadeh hassan Farhangi Seyed ali Asghar Akbari Mousavi Arman Ghahramani School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

Revealing grains and very fine dendrites in a solidified weld metal of aluminum–magnesium–silicon alloys is difficult and thus,there is no evidence to validate the micro-and meso-scale physical models for hot cracks. In this research, the effect of preheating on the microstructure and hot crack creation in the pulsed laser welding of AA 6061 was investigated by an optical microscope and field emission electron microscopy. Etching was carried out in the gas phase using fresh Keller’s reagent for 600 s. The results showed that the grain size of the weld metal was proportional to the grain size of the base metal and was independent of the preheating temperature. Hot cracks passed the grain boundaries of the weld and the base metal. Lower solidification rates in the preheated samples led to coarser arm spacing;therefore, a lower cooling rate. Despite the results predicted by the micro and meso-scale models, lower cooling rates resulted in increased hot cracks. The cracks could grow in the weld metal after solidification;therefore, hot cracks were larger than predicted by the hot crack prediction models.

关键词： etching technique laser welding inter-dendritic spacing grain size aluminum–magnesium–silicon alloys hot crack formation model

Levels of Lead (Pb), Cadmium (Cd) and Cobalt (Co) in Cow Milk from Selected Areas of Zanzibar Island, Tanzania

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American Journal of Analytical Chemistry 2023年第7期14卷 287-304页

作者： hassan Rashid ali Mwanahija Mohamed Ame Mohammed ali Sheikh Said Suleiman Bakari School of Natural and Social Sciences The State University of Zanzibar Zanzibar Tanzania Tropical Research Centre for Oceanography Environment and Natural Resources The State University of Zanzibar Zanzibar Tanzania

Milk is one of the very important nutrients of human diet. The presence of toxic elements in milk may threaten the public health. This study reports the levels of Cadmium (Cd), Cobalt (Co) and Lead (Pb) in raw cow’s milk collected from different areas of Zanzibar Island during March - May 2016. The samples of raw milk were analyzed by Thermo Scientific-Atomic Absorption Spectrophotometer for quantitative determination of the metals in the matrix. The concentration of Co in this study ranged from ND at Mwanakwerekwe (MK1 and MK2) to a maximum of 0.004 mg/L at Mshelishelini (MS5) and Fuoni (F5) sites with mean concentration of 0.020 ± 0.003 mg/L for all sites. Concentration of Pb ranged between 0.05 - 0.51 mg/L at Fuoni (F7) and Mwanakwerekwe (MK1) respectively, with mean concentration of 0.263 ± 0.031 mg/L for all sites. However, Cd was only detected in one sample collected at Fuoni (F3) with a concentration of 0.001 mg/L. The results revealed that cow’s milk is contaminated with toxic metals, particularly Pb which exceeded the WHO maximum permissible level of 0.02 mg/L. The study furthermore sheds light on possible consequences to public health. It is recommended that, stakeholders especially in Zanzibar such as Zanzibar Food and Drug Authorities (ZFDA) and Zanzibar Bureau of Standards (ZBS) as well as researchers, use the findings of this study for policy making, future study plans, formulation of technical strategies to control milk contamination, risk assessment and develop new alternative methods to measure milk contamination even at a low detection limit for the sake of the consumers’ welfare before posing any serious effects to their health.

关键词： Milk Cobalt Lead Cadmium Zanzibar

Daily Lifestyle Habits as Risk Factors for Plaque-Induced Gingivitis and Periodontitis Severity and Grading among Samples of Dental Students at King Khalid University

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International Journal of Clinical Medicine 2023年第2期14卷 65-78页

作者： Mohammed M. A. Abdullah Al-Abdaly Amer hassan Alasmari Feras ali Alsaeed ali Abdullah ali Alqhtani Fahad hassan Alhifthi Yasir Saad Jaadan Periodontics and Community Dental Sciences College of Dentistry King Khalid University Abha Saudi Arabia College of Dentistry King Khalid University Abha Saudi Arabia

Objective: To assess daily lifestyle habits as risk factors for plaque-induced gingivitis and periodontitis severity and grading among samples of dental students at King Khalid University. Material and Methods: This study included 150 male participants. They were divided according to the levels into three equal groups: levels 5, 6, and 7 (group I), levels 8, 9, 10 (group II) and levels 11, 12, and interns (group III). This study consisted of questions related to age, gender, educational level, father’s education, mother’s education, home ownership, brushing teeth more than or twice a day, in addition to daily lifestyle habits that were daily smoking, daily use of sugary drinks, and daily use of sugary foods. Some clinical parameters of plaque-induced gingivitis and periodontitis and the percentage of radiographic bone loss were recorded. All data were collected and analyzed using Tukey’s test and Chi-square test. A P-value of less than 0.5 (p Results: One hundred fifty male dental students of different levels in the college of dentistry at King Khalid University participated in the study in three groups (I, II, and III). The mean age of group III is more than that of group II and group I, with highly statistically significant differences (p 30%) were more among the participants in group I than the participants in groups III and II. There was an increase in the percentage of affected participants with stages III and IV of clinical attachment loss (CAL), periodontal pocket depth (PPD), radiographic bone loss (%RBL), tooth mobility, as well as glycated hemoglobin (HbA1c) test values (>7%), and the number of cigarettes smoked per day (>10 cigs) in group III more than in group II and I. Conclusion: We conclude that the severity and grading of plaque-induced gingivitis were higher among the participants in group I, while the severity and grading of periodontitis were higher among the participants in group III due to the different impact of their daily lifestyle habits.

关键词： Daily Lifestyle Dental Students King Khalid University Periodontitis Plaque-Induced Gingivitis

Spatial variability of soil microbial indices in common alder COMMON ALDER(Alnus glutinosa) stands using a geostatistical approach in northern Iran

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Journal of Forestry Research 2019年第2期30卷 679-688页

作者： Neda Ghorbanzadeh ali Salehi hassan Pourbabaei ali Ashraf Soltani Tolarod Seyed Jalil Alavi Department of Forestry Faculty of Natural ResourcesUniversity of Guilan Department of Soil Science Faculty of Agriculture and Natural Resources University of Mohaghegh Ardabili Department of Forestry Faculty of Natural Resources and Marine Sciences University of Tarbiat Modares

Microbial indices and their spatial patterns are strongly affected by environmental factors. Spatial variability of soil properties is one of the most important causes of variability in soil microbial indices. This research was conducted in the Caspian forest to assess spatial variabilities and frequency distributions of microbial *** soil samples were taken using a grid sampling design 40 9 40 m. Microbial indices, organic carbon,nitrogen and pH were determined. Soil variable distributions showed that microbial indices had abnormal distributions. Logarithmic transformation produced normal distribution. Spatial continuity using geostatistical(variogram) was studied and maps obtained by point *** variograms revealed the presence of spatial autocorrelation. The results indicate that spatial dependence of soil microbial indices was affected by non-intrinsic factors and forest management procedures. The maps show that soil microbial indices and soil properties have spatial variability. The spatial pattern of microbial indices was correlated to organic carbon and nitrogen.

关键词： Variograms Soil microbial indices Spatial distribution Natural forest Iran