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Overexpression of the peroxidase gene ZmPRX1 increases maize seedling drought tolerance by promoting root development and lignification

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The Crop Journal 2024年第3期12卷 753-765页

作者： Xiuzhen Zhai Xiaocui Yan tinashe Zenda Nan Wang Anyi Dong Qian Yang Yuan Zhong Yue Xing Huijun Duan State Key Laboratory of North China Crop Improvement and Regulation Key Laboratory of Crop Germplasm Resources in North China Ministry of EducationCollege of AgronomyHebei Agricultural UniversityBaoding 071001HebeiChina

Drought is a main abiotic stress factor hindering plant growth,development,and crop ***,it is crucial to understand the mechanisms by which plants cope with drought ***,the function of the maize peroxidase gene ZmPRX1 in drought stress tolerance was investigated by measurement of its expression in response to drought treatment both in a ZmPRX1 overexpression line and a mutant *** higher root lignin accumulation and seedling survival rate of the overexpression line than that of the wild type or mutant support a role for ZmPRX1 in maize drought tolerance by regulating root development and ***,yeast one-hybrid,Dule luciferase and ChIP-qPCR assays showed that ZmPRX1 is negatively regulated by a nuclear-localized ZmWRKY86 transcription *** gene could potentially be used for breeding of drought-tolerant cultivars.

关键词： Drought tolerance Maize ZmPRX1 Root development Lignin biosynthesis

新冠疫情对中非贸易影响的研究 ——来自南部非洲发展共同体（南共体）的证据

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新冠疫情对中非贸易影响的研究 ——来自南部非洲发展共同体（南...

作者： Munemo tinashe Cleopas 江西财经大学

学位级别：硕士

新冠肺炎疫情引发的中国和非洲之间贸易壁垒是巨大的,非常严重。积极促进贸易的措施日益被视为改善全球商品自由流动的必要条件。本研究评估了2020年4月至2021年4月期间新冠肺炎疫情对中非贸易,特别是南共体成员国贸易的影响。该研究利... 详细信息

新冠肺炎疫情引发的中国和非洲之间贸易壁垒是巨大的,非常严重。积极促进贸易的措施日益被视为改善全球商品自由流动的必要条件。本研究评估了2020年4月至2021年4月期间新冠肺炎疫情对中非贸易,特别是南共体成员国贸易的影响。该研究利用南共体16个成员国的面板数据,采用引力模型和泊松伪极大似然估计(PPML)进行估计,结果发现疫情导致的封锁和新冠肺炎感染在更大程度上对中国与南共体成员国的贸易产生了负面影响,贸易分别减少了3.95%和1.41%。本文建议相关政府实施边境监管系统和生产流程自动化的政策,以最大限度地减少人为干扰;加强公共支出计划和鼓励私人投资于卫生部门,以提高各国对大流行病的抵御能力,这是至关重要的;最后,各国政府在实施预防措施时,不应脱离经济发展政策,而应同时实施相关政策以促进国民经济增长和贸易发展。

关键词：中非贸易新冠感染死亡封锁

Longevity Swaps:Derivatives for Hedging Longevity Risk Embedded in Variable Annuities(Pension Plans)

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Longevity Swaps:Derivatives for Hedging Longevity Risk Embed...

作者： Blessing tinashe Manzou 浙江科技学院

学位级别：硕士

Longevity risk is becoming an increasing important risk facing individuals in developed economies and financial institutions are busy developing products to hedge this *** is a good social development but for pension plans it is a risk because it allows them to make loss as they pay more liabilities than they *** many years insurance companies has underestimated the longevity of individuals as survival probabilities increases across the developed *** improvement has caused unsettlement in the future of the annuity and pension providers as they try to find ways to reduce this *** paper proposes the use of longevity swaps as a hedging tool on which a life insurer（annuity provider）can transfer the longevity risk to financial *** LeeCarter model is calibrated on Australian male population to forecast mortality *** the Lee-Carter model we forecast the mortality rates and construct 1,000 sample paths by means of Monte Carlo *** each sample path continue by calculating the payoff of the longevity index swap by looking at the change in mortality rate with respect to the fixed mortality *** fixed mortality rate is obtained from the Australian life *** maturity time a settlement is calculated and the risk is transferred to the hedge provider（financial market）through a longevity swaps and thus longevity risk is *** index swap pays out in case the forecasted mortality rate becomes smaller than the fixed mortality *** this case the clients of an insurer live longer than expected,which means that the liabilities of the insurer are higher than anticipated on beforehand.

关键词： longevity risk variable annuities hedging longevity index swaps

The Moderating Effect of Board Mechanisms on the Relationship between Capital Structure and Firm Performance:evidence from Zimbabwean Listed Firms

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The Moderating Effect of Board Mechanisms on the Relationshi...

作者： tinashe Raymond Ambai 东北财经大学

学位级别：硕士

This study examines the moderating effect of board mechanisms on the relationship between capital structure and firm performance for 35 non-financial firms listed on the Zimbabwe Stock Exchange(ZSE)during the 2013-2020 *** listed after 2013 were excluded from the study to avoid using unbalanced data for *** majority of the data was collected from the ZSE database,whilst the other data were collected from individual annual financial reports of these *** study used OLS Ordinary Least squares to estimate and predict the results from this panel *** panel data regression methods were used for each regression model in the *** results from the panel data regression revealed evidence of the significant positive relationship between capital structure and firm *** results give credence to the assertion that firms on the ZSE follow the tradeoff *** also show that board mechanisms elements like board meetings and board composition have a positive moderating *** on the other hand,board size does not show any moderating effects due to insignificant *** on these results,board mechanisms can be seen as an influential tool that can be used by firms to alter the relationship between capital structure and firm performance.

关键词： Corporate governance Board Mechanisms Capital Structure Internal controls Firm perfomance Agency theory

Assessment of Distribution and Composition of Quarry Mine Dust: Case of Pomona Stone Quarries, Harare

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Atmospheric and Climate Sciences 2012年第1期2卷 52-59页

作者： Emaculate Madungwe tinashe Mukonzvi 不详

The study aimed at assessing the distribution and composition of dust produced at Pomona Stone Quarry mine in Harare, Zimbabwe. The source contribution to ambient PM2.5 and PM10 dust levels were quantified and their spatial distribution from the quarry to the receptor (community). The study also analysed the pH of soils around the mine, SiO2 and Al2O3 levels in quarry dust. Data was collected through direct observations, personal communications, experiments, soil and dust sampling and analyses. Dust sampling was done in January, April and August, to assess the effect of meteorological conditions on dust concentrations in two phases. Phase 1 was conducted during plant shut down (baseline measurements) while phase 2 was carried out during full plant operations (normal operating conditions), to assess the effect of quarry operations on the surrounding areas. Within the quarry production processes, crushing stage was the most dust emitting stage. Phase 1 dust results showed that both respirable (PM2.5) and inhalable (PM10) dust at all stages were below the legal limit, thus below 35 mg/m3 (respirable) and 180 mg/m3 (inhalable). Highest dust levels (209.9 mg/m3 inhalable and 69.01 mg/m3 respirable) were recorded in August, followed by April (206.9 mg/m3 inhalable and 67.52 mg/m3 respirable) then January (206.82 mg/m3 inhalable and 65.27 mg/m3 respirable). At all stages, highest dust concentrations for both parameters were recorded near the plant and decreased with increasing distance from the plant ( ranging from 209.9 mg/m3 - 19.41 mg/m3 inhalable and 69.01 mg/m3 - 14.23 mg/m3 respirable). This was attributed to the effect of particle size. August recorded the biggest area for both parameters falling within the non-permissible category, followed by April then January. The findings also revealed that the quarry dust contained higher levels of SiO2 (0.752 mg/cm3) which were 7 times higher than the recommended 0.1 mg/cm3 (NSSA). Low Al2O3 levels of 0.102 mg/cm3 were record

关键词： Dust PM10 PM 2.5 Quarry Mine Receptor

Design and Simulation of IoT Systems Using the Cisco Packet Tracer

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Advances in Internet of Things 2021年第2期11卷 59-76页

作者： Norman Gwangwava tinashe B. Mubvirwi Mechanical Energy and Industrial Engineering Botswana International University of Science and Technology Palapye Botswana Sable Chemical Industries Limited Kwekwe Zimbabwe

Design and implementation of Internet of Things (IoT) systems require platforms with smart things and components. Two dominant architectural approaches for developing IoT systems are mashup-based and model-based approaches. Mashup approaches use existing services and are mainly suitable for less critical, personalized applications. Web development tools are widely used in mashup approaches. Model-based techniques describe a system on a higher level of abstraction, resulting in very expressive modelling of systems. The article uses Cisco packet tracer 7.2 version, which consists of four subcategories of smart things—home, smart city, industrial and power grid, to design an IoT based control system for a fertilizer manufacturing plant. The packet tracer also consists of boards—microcontrollers (MCU-PT), and single boarded computers (SBC-PT), as well as actuators and sensors. The model facilitates flexible communication opportunities among things—machines, databases, and Human Machine Interfaces (HMIs). Implementation of the IoT system brings finer process control as the operating conditions are monitored online and are broadcasted to all stakeholders in real-time for quicker action on deviations. The model developed focuses on three process plants;steam raising, nitric acid, and ammonium nitrate plants. Key process parameters are saturated steam temperature, fuel flowrates, CO and SOx emissions, converter head temperature, NOx emissions, neutralisation temperature, solution temperature, and evaporator steam pressure. The parameters need to be monitored in order to ensure quality, safety, and efficiency. Through the Cisco packet tracer platform, a use case, physical layout, network layout, IoT layout, configuration, and simulation interface were developed.

关键词： Internet of Things (IoT) Smart Sensors Wireless Sensors Process Control Cisco Packet Tracer Simulation Smart Factory Cloud Computing

甘油三酯-血糖指数与急性冠脉综合征合并糖尿病患者PCI围手术期心血管不良事件的关系

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甘油三酯-血糖指数与急性冠脉综合征合并糖尿病患者PCI围手术期心...

作者： tinashe Chikawa 大连医科大学

学位级别：硕士

背景许多研究发现甘油三酯-葡萄糖指数(TyG指数)与心血管疾病的患病率、严重程度和预后之间存在某种关系。然而,TyG指数与患有2型糖尿病合并急性冠状动脉综合征的患者经皮冠状动脉介入术围手术期终点事件发生的关系尚不清楚。目的1.评价... 详细信息

背景许多研究发现甘油三酯-葡萄糖指数(TyG指数)与心血管疾病的患病率、严重程度和预后之间存在某种关系。然而,TyG指数与患有2型糖尿病合并急性冠状动脉综合征的患者经皮冠状动脉介入术围手术期终点事件发生的关系尚不清楚。目的1.评价有2型糖尿病合并急性冠状动脉综合征的患者接受经皮冠状动脉介入治疗的甘油三酯-葡萄糖指数与疾病严重程度及围手术期终点事件发生的关系。2.评价甘油三酯-葡萄糖指数与传统心血管危险因素的关系。方法本研究纳入2020年1月至2020年12月期间在大连医科大学第二附属医院急性冠脉综合征合并糖尿病行经皮冠状动脉介入术患者813例,其中男性475例,平均年龄67±7.8岁,女性338例,平均年龄67.6±7.6岁。TYG指数计算方式为ln(空腹甘油三酯水平[mg/d L]×空腹血浆葡萄糖水平[mg/d L]/2)主要终点事件为全因死亡,非致死性卒中,计划外的再次血运重建和心血管不良事件,次要终点事件包括围手术期心肌损伤/梗死、急性肾损伤、新发或心力衰竭加重、新发心律失常、出血并发症(介入手术部位和非介入手术部位)。通过logistic回归分析评估TyG指数与心血管不良事件之间的关系。结果本研究共纳入813名患者(平均年龄:67.2±7.7,女性41.6%),其中124例(15.4%))发生了主要终点事件。主要终点事件发生率为:急性肾损伤25例(3.3%),PCI后心衰56例(6.7%),出血并发症7例(0.9%),PCI后心肌损伤例91(10.0%),PCI后心律失常19例(2.2%)。在发生心律失常的患者中,9例(47%)发生室性早搏,2例(10.5%)发生房颤,8例(42%)发生房性早搏。在男性和女性患者中,TYG指数与心血管不良事件发生率无关。女性患者中(OR 1.036(95%CI0.738-1.456;P=0.837)男性患者中,(OR 1.235(95%CI 0.879-1.965P=0.182)在女性患者中,TYG指数与急性肾损伤:OR 2.990(95%CI 1.584-5.642,P=<0.001)和心力衰竭OR 1.812(95%CI 1.156-2.842,P=0.010)的发生相关,但与女性患者的心肌损伤、出血或心律失常无关。在男性患者中,该指数与任何次要终点事件均无明显相关。结论在接受PCI治疗的ACS合并T2DM女性中,TyG指数与主要终点事件不具有相关性,而与部分次要终点显著相关,这表明TyG指数可能是ACS合并T2DM的女性PCI后围手术期主要不良心血管事件的重要预测指标。TyG指数易于测量并适用于临床实践,在接受PCI治疗的2型糖尿病和急性冠脉综合征的绝经后妇女中,TyG指数变化与围手术期急性肾损伤和心力衰竭的发生显著相关,但与出血并发症、PCI后心肌损伤和心律失常的发生无关。

关键词：甘油三酯-葡萄糖指数心血管不良事件急性冠状动脉综合征 2型糖尿

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津巴布韦农民正规融资可得性影响因素研究

津巴布韦农民正规融资可得性影响因素研究

作者： tinashe Mangudhla 江苏大学

学位级别：硕士

农业资金已成为发展中国家消除饥饿和贫困的关键。在津巴布韦,农产品销售的回报对该国国内生产总值的贡献约为20%,同时为75%以上的人口提供了生计。然而,令人不安的是,鉴于农业对津巴布韦经济的重要性,获得正规信贷融资仍然是一项挑战... 详细信息

农业资金已成为发展中国家消除饥饿和贫困的关键。在津巴布韦,农产品销售的回报对该国国内生产总值的贡献约为20%,同时为75%以上的人口提供了生计。然而,令人不安的是,鉴于农业对津巴布韦经济的重要性,获得正规信贷融资仍然是一项挑战。因此,农民仍然难以获得贷款,以支持津巴布韦的农业活动。因此,这项研究的主要目标是评估农民如何资助他们在津巴布韦的农业活动。由于数据农业不可用,本研究利用了原始数据。因此,向小规模农民发放了调查表。在收集数据后,用于回归估计和部分最小方块结构方程建模(PLS-SEM)进行分析。为了测试我们申请的研究方法是否可靠且有效进行评估,我们进行了布劳施异教徒测试、ANOVA测试、线性诊断测试以及异地-单陷阱比率(HTMT),该比率适用于歧视性有效性。布劳施异质性测试用于测试异质性,在我们的数据中未发现异质性。此外,ANOVA测试检查变量之间是否存在统计差异。结果表明,依赖变量和独立变量之间存在统计学意义,在线性诊断测试后,我们的数据中未发现线性问题。异质-单陷阱比率(HTMT)表明,引导式置信区间结果也有利于构造的歧视性有效性。因此,这意味着满足了所有模型评估标准,这进一步支持了我们分析中所用措施的可靠性、有效性和稳健性。我们注意到从PSL-SEM获得的结果和回归估计是一致的。我们特别感兴趣的是,资产(个人和农场资产)、生产率、农场规模和所有权年限(独立变量)在获得正式融资方面起着关键作用。虽然农业地位对津巴布韦传统贷款的可及性没有影响。因此,在津巴布韦,银行是主要为大规模农民(商业农民)提供资金的首选。我们进一步认识到,资产(抵押品)是银行考虑的基本要求,这是许多小农户无法企及的要求。有趣的是,结果表明,农场地位(季节性农民或全职农民)不影响贷款申请。这意味着,农业地位不是贷款发放企业在发放农业活动贷款时考虑的一个因素,然而,这使农民处于有利地位。我们建议农民需要将精力投入到产出以外的可持续农业活动上,但要专注于利润更高的项目。同样,农业也是最独特、最广泛、最复杂的产业之一:因此,我们建议所有金融机构重视研发,这是创新、新产品和服务开发的关键要素。此外,我们建议政府制定解决和重新引入农场所有权的方法,以方便金融机构获得贷款资金。因此,农民财产所有权文件需要从政府所有权转移到用户或耕地所有者。重新引入农场所有权将允许转售农场庄园。除了促进先进农业和机械化设备的快速转移外,我们建议政府是否可以与生产这些工具和设备的国家签订战略双边协议。除了双边协定,各国之间对涉及农业部门的交易和交易也应大幅放宽贸易限制。由于农业是津巴布韦最重要的产业之一,因此与金融机构和其他利益攸关方的伙伴关系对该部门的增长至关重要。因此,采取这些政策战略将确保整个农业部门价值链的全面增长,这将对其他重要产业造成溢出效应。

关键词：正规信贷农业部门影响因素农户银行业可得性 PSL-SEM

Improved xylitol production by expressing a novel D-arabitol dehydrogenase and co-biotransformation

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Improved xylitol production by expressing a novel D-arabitol...