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Effect of inorganic arsenic in paddy soil on the migration and transformation of selenium species in rice plants

Journal of Environmental Sciences 2024年第9期143卷 35-46页

作者： ganga raj pokhrel Kaiteng Wang Kaiyang Ying Yongchen Wu Ze Wang Xi Zhu Can Qu Hong Li Fengfu Fu Guidi Yang Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring Key Laboratory for Medicinal Plant Chemistry and Chemical BiologyCollege of JunCao Science and EcologyFujian Agriculture and Forestry UniversityFuzhou 350002China Department of Chemistry Birendra Multiple CampusTribhuvan UniversityChitwan 00977-44200BharatpurNepal Key Laboratory for Analytical Science of Food Safety and Biology of Ministry of Education Fujian Provincial Key Lab of Analysis and Detection for Food SafetyCollege of ChemistryFuzhou UniversityFuzhou 350116China

Selenium(Se)in paddy rice is one of the significant sources of human Se nutrition.However,the effect of arsenic(As)pollution in soil on the translocation of Se species in rice plants is unclear.In this research,a pot experiment was designed to examine the effect of the addition of 50 mg As/kg soil as arsenite or arsenate on the migration of Se species from soil to indica Minghui 63 and Luyoumingzhan.The results showed that the antagonism between inorganic As and Se was closely related to the rice cultivar and Se oxidation state in soil.Relative to the standalone selenate treatment,arsenite significantly(p<0.05)decreased the accumulation of selenocystine,selenomethionine and selenate in the roots,stems,sheaths,leaves,brans and kernels of both cultivars by 21.4%-100.0%,40.0%-100.0%,41.0%-100%,5.4%-96.3%,11.3%-100.0% and 26.2%-39.7% respectively,except for selenocystine in the kernels of indica Minghui 63 and selenomethionine in the leaves of indica Minghui 63 and the stems of indica Luyoumingzhan.Arsenate also decreased(p<0.05)the accumulation of selenocystine,selenomethionine and selenate in the roots,stems,brans and kernels of both cultivars by 34.9%-100.0%,30.2%-100.0%,11.3%-100.0% and 5.6%-39.6%respectively,except for selenate in the stems of indica Minghui 63.However,relative to the standalone selenite treatment,arsenite and arsenate decreased(p<0.05)the accumulation of selenocystine,selenomethionine and selenite only in the roots of indica Minghui 63 by 45.5%-100.0%.Our results suggested that arsenite and arsenate had better antagonism toward Se species in selenate-added soil than that in selenite-added soil;moreover,arsenite had a higher inhibiting effect on the accumulation of Se species than arsenate.

关键词： Rice(Oryza sativa L.) Inorganic arsenic Selenium species Translocation Antagonistic effect

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Automation and Orchestration of Zero Trust Architecture:Potential Solutions and Challenges

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Machine Intelligence Research 2024年第2期21卷 294-317页

作者： Yang Cao Shiva raj pokhrel Ye Zhu Robin Doss Gang Li Centre for Cyber Resilience and Trust Deakin UniversityBurwood 3125Australia School of Information Technology Deakin UniversityGeelong 3216Australia

Zero trust architecture(ZTA)is a paradigm shift in how we protect data,stay connected and access resources.ZTA is non-perimeter-based defence,which has been emerging as a promising revolution in the cyber security field.It can be used to continuously maintain security by safeguarding against attacks both from inside and outside of the network system.However,ZTA automation and orchestration,towards seamless deployment on real-world networks,has been limited to be reviewed in the existing literature.In this paper,we first identify the bottlenecks,discuss the background of ZTA and compare it with traditional perimeter-based security architectures.More importantly,we provide an in-depth analysis of state-of-the-art AI techniques that have the potential in the automation and orchestration of ZTA.Overall,in this review paper,we develop a foundational view on the challenges and potential enablers for the automation and orchestration of ZTA.

关键词： Zero trust architecture cyber security artificial intelligence access control authentication

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尼泊尔卡纳利省药用和芳香植物对国内生产总值的贡献

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资源与生态学报:英文版 2023年第5期14卷 1104-1112页

作者： Kamal raj ARYAL Anup GURUNG Prabin PAUDEL rajendra Kumar BASUKALA Shiva PARIYAR Arjun THAPA Hikmat Kumar SHAHI ganga SHAH Saroj PANTHI 卡纳利省森林研究和培训中心苏尔赫特21700尼泊尔国立康源大学生物环境学系江原道春川市24341韩国甘达基省森林、环境和土壤保护部博卡拉33700尼泊尔甘达基省森林局博卡拉33700尼泊尔加德满都Balkhu小型哺乳动物保护和研究基金会加德满都44618尼泊尔苏尔赫特中西部大学苏尔赫特21700尼泊尔

自古以来,药用和芳香植物(MAPs)在尼泊尔就被广泛种植并用于医疗保健和治疗实践,在尼泊尔社区拥有很重要的文化、宗教和经济价值。近年来,MAPs部门在尼泊尔尤其是喜马拉雅山区是一个不断发展的商业部门,为低收入人群提供生计机会。本研... 详细信息

自古以来,药用和芳香植物(MAPs)在尼泊尔就被广泛种植并用于医疗保健和治疗实践,在尼泊尔社区拥有很重要的文化、宗教和经济价值。近年来,MAPs部门在尼泊尔尤其是喜马拉雅山区是一个不断发展的商业部门,为低收入人群提供生计机会。本研究评估了MAPs对尼泊尔卡纳利省国内生产总值(GDP)的贡献。卡纳利省共鉴定出58种MAPs。人们发现,这些一年生、两双年生和多年生植物的各个部分都可被用作药物、香水和食品。在2019/2020财年,卡纳利省的MAP产生的经济产出为1607.38亿尼泊尔卢比(13.9亿美元),相当于卡纳利省GDP的1.03%,相当于全国GDP的0.02%。然而,调查结果显示,由于未纳入药用植物的民族植物学用途,目前的GDP估算低估了MAPs部门对国家GDP的贡献,如果将人们从这一部门获得的所有收入和环境利益都体现在国民账户体系中,进行估价和记录,那么MAPs的GDP将远远高于本研究中的估算值。我们得出结论,MAPs对卡纳利省和尼泊尔的GDP有合理的贡献。

关键词：非木材林产品税费贸易尼泊尔

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Importance of Historicity in Analysis of Gender Issues

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Journal of Sociology Study 2020年第5期10卷 216-222页

作者： Shukra raj Adhikari ganga Acharya Tribhuvan University KathmanduNepal

On the basis of sex and biological categories,society assigns the socio-cultural authority and responsibilities.Sex wises different socio-cultural responsibilities and authority;performances are recognized as gender.All of the socio-cultural creations are the factors of gender construction.The aim of this paper is to explore the discourses of gender in terms of historical circumstances and social context.Mainly,secondary data are used in this article.The information is collected and analyzed by the historical content analysis method under the qualitative research approach.It is difficult to identify the real form of gender issues without analyzing the social structure according to the historical context,so it is possible to analyze the real gender issues only by analyzing the social structure in historical context.

关键词： construction discourse gender historical social structure

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Assessment of Heavy Metals in Deep Groundwater Resources of the Kathmandu Valley, Nepal

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Journal of Environmental Protection 2016年第4期7卷 516-531页

作者： Suman Man Shrestha Kedar Rijal Megh raj pokhrel Central Department of Environmental Science Tribhuvan University Kirtipur Nepal Central Department of Chemistry Tribhuvan University Kirtipur Nepal

A study was carried out to address distribution of some heavy metals in deep groundwater resources of the Kathmandu Valley. Groundwater samples were analyzed for pH, ORP, EC, iron, manganese, zinc, and arsenic in 41 deep groundwater wells during pre monsoon and post monsoon seasons for two consecutive years. The study showed elevated concentrations of iron and manganese in the groundwater of the valley. The occurrence of elevated concentrations of arsenic was also exhibited and observed up to 0.160 mg/L. The spatial distribution patterns demonstrated elevated levels of EC, iron, manganese, zinc, and arsenic in central groundwater district (CGWD) of the valley. The monitored parameters except ORP are not significantly correlated with studied time series, inferring similar distribution of the metals. Correlation analysis and principal component analysis (PCA) were performed to find out relationships among examined parameters and metals. The ORP has strong negative correlations with iron, manganese, and arsenic, suggesting reductive mobilization mechanism of the metals in the groundwater. PCA results showed that iron and manganese with high positive loading factors were due to common natural source of origin of these metals in the groundwater, while negative loading factors of pH and ORP indicated that iron and manganese mobilization was favorable in low pH and reducing environment. Cluster analysis (CA) evidenced high mineralization in most of the wells in the CGWD.

关键词： Heavy Metals Deep Groundwater Principal Component Analysis Cluster Analysis Mineralization

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Cybersecurity: A Stochastic Predictive Model to Determine Overall Network Security Risk Using Markovian Process

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Journal of Information Security 2017年第2期8卷 91-105页

作者： Nawa raj pokhrel Chris P. Tsokos Department of Mathematics and Statistics University of South Florida Tampa USA

There are several security metrics developed to protect the computer networks. In general, common security metrics focus on qualitative and subjective aspects of networks lacking formal statistical models. In the present study, we propose a stochastic model to quantify the risk associated with the overall network using Markovian process in conjunction with Common Vulnerability Scoring System (CVSS) framework. The model we developed uses host access graph to represent the network environment. Utilizing the developed model, one can filter the large amount of information available by making a priority list of vulnerable nodes existing in the network. Once a priority list is prepared, network administrators can make software patch decisions. Gaining in depth understanding of the risk and priority level of each host helps individuals to implement decisions like deployment of security products and to design network topologies.

关键词： Vulnerability Attack Graph Markov Model Exploitability CVSS FIRST NVD IDS

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Assessment of Arsenic Contamination in Deep Groundwater Resources of the Kathmandu Valley, Nepal

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Journal of Geoscience and Environment Protection 2015年第10期3卷 79-89页

作者： Suman Man Shrestha Kedar Rijal Megh raj pokhrel Central Department of Environmental Science Tribhuvan University Kirtipur Kathmandu Nepal Central Department of Chemistry Tribhuvan University Kirtipur Kathmandu Nepal

This study was carried out to assess arsenic in deep groundwater resources in the Kathmandu Valley, Nepal and to predict arsenic mobilization process in relation to iron, manganese, pH and ORP. Forty-one deep groundwater samples were collected during pre monsoon and post monsoon in 2013. The depths of the wells were ranged from 84 to 304 m. In pre monsoon and post monsoon, arsenic concentration in 17% and 26% of examined groundwater wells, respectively exceeded permissible World Health Organization (WHO) guideline value of 0.010 mg/L for drinking water. The concentrations of arsenic were in the range between < 0.003 to 0.137 mg/L. The study demonstrated elevated concentrations of iron and manganese in the groundwater. Arsenic is highly correlated with iron and manganese. The strong negative correlation between arsenic and ORP indicates that arsenic mobilization occurs under reducing condition. These distinct relationships indicate that arsenic release is considered to be affected by the reductive dissolution of Fe/Mn oxides in the groundwater. Arsenic has very weak negative correlation with pH suggesting less effect of pH on arsenic mobilization. Arsenic is not significantly correlated with the season which infers similar distribution of arsenic in both seasons. Arsenic varies spatially in groundwater of the valley showing high concentrations in central groundwater district.

关键词： Arsenic Deep Groundwater Reductive Dissolution Kathmandu Valley

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Cybersecurity: Time Series Predictive Modeling of Vulnerabilities of Desktop Operating System Using Linear and Non-Linear Approach

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Journal of Information Security 2017年第4期8卷 362-382页

作者： Nawa raj pokhrel Hansapani Rodrigo Chris P. Tsokos Department of Mathematics and Statistics University of South Florida Tampa FL USA School of Mathematical and Statistical Sciences University of Rio Grande Valley Edinburg TX USA

Vulnerability forecasting models help us to predict the number of vulnerabilities that may occur in the future for a given Operating System (OS). There exist few models that focus on quantifying future vulnerabilities without consideration of trend, level, seasonality and non linear components of vulnerabilities. Unlike traditional ones, we propose a vulnerability analytic prediction model based on linear and non-linear approaches via time series analysis. We have developed the models based on Auto Regressive Moving Average (ARIMA), Artificial Neural Network (ANN), and Support Vector Machine (SVM) settings. The best model which provides the minimum error rate is selected for prediction of future vulnerabilities. Utilizing time series approach, this study has developed a predictive analytic model for three popular Desktop Operating Systems, namely, Windows 7, Mac OS X, and Linux Kernel by using their reported vulnerabilities on the National Vulnerability Database (NVD). Based on these reported vulnerabilities, we predict ahead their behavior so that the OS companies can make strategic and operational decisions like secure deployment of OS, facilitate backup provisioning, disaster recovery, diversity planning, maintenance scheduling, etc. Similarly, it also helps in assessing current security risks along with estimation of resources needed for handling potential security breaches and to foresee the future releases of security patches. The proposed non-linear analytic models produce very good prediction results in comparison to linear time series models.

关键词： ARIMA NVD ANN OS SVM CVE SMAPE

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Surface Modification of the Biowaste for Purification of Wastewater Contaminated with Toxic Heavy Metals—Lead and Cadmium

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Advances in Chemical Engineering and Science 2013年第3期3卷 178-184页

作者： Bindra Shrestha Jagjit Kour Puspa Lal Homagai Megh raj pokhrel Kedar Nath Ghimire Central Department of Chemistry Tribhuvan University Kathmandu Nepal

The surface of a biowaste was modified by introduction of amino group for the purification of wastewater contaminated with heavy metals. In this study waste tea leaf was used as a biowaste which was an economic and efficient bioadsorbent. The aminated tea leaves were characterized by spectral and elemental analysis. The adsorption capacity of the surface modified biosorbent was studied as the function of solution pH, concentration of metal ions and contact time of adsorption. The applicability of Langmuir isotherm was tested. The adsorption capacities were found to be 83.04 mg/g and 57 mg/g for Pb (II) and Cd (II), respectively. The biosorbent was regenerated by desorption of the metal loaded adsorbent with 0.1 M HNO3. These results showed that the aminated tea leaves may be an attractive alternative for treatment of wastewater contaminated with heavy metals.

关键词： Bioadsorbent Heavy Metals Wastewater Amination Langmuir Isotherm

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Innovative Practices for the Promotion of Local/Indigenous Knowledge for Disaster Risk Reduction Management in Sudur Paschim Province,Nepal

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Journal of Geographical Research 2021年第3期4卷 1-11页

作者： Kabi Prasad pokhrel Shambhu Prasad Khatiwada Narayan Prasad Paudyal Keshav raj Dhakal Chhabi Lal Chidi Narayan Prasad Timilsena Dhana Krishna Mahat Central Department of Geography Education Tribhuvan UniversityKathmanduNepal Central Department of Geography Tribhuvan UniversityKathmanduNepal Central Department of Science Education Tribhuvan UniversityKathmanduNepal PhD Research Scholar of Geography Education Tribhuvan UniversityKathmanduNepal

This study is an attempt to point out the different types of natural hazards in Sudur Paschim province of Nepal where environmental degradation processes such as deforestation,desertification,biodiversity loss,soil crisp and watershed degradation are rising trends.Using participatory method multi hazard prone areas were identified with type and intensity.Multi criteria evaluation method was applied to prioritize replicable actions with location-specific innovative practices and their legitimization for integrating local and indigenous knowledge into mainstream education,science and policy with a view to incorporate local and indigenous knowledge as live science in disaster and climate change education.Findings of the study reveal that varieties of natural hazards in combination with social factors such as poverty,conflict and inequality have resulted frequent disasters and social vulnerabilities in many parts of the province.Traditionally,indigenous and local people have responded threats of multi hazards by using their traditional knowledge and skills which has evolved over generations,and continue to adapt to future changes.These traditional,often faith-based,beliefs and practices were found to use as the key to their resilience in the face of natural hazards.However,many communities have been lost their knowledge as the elderly die without transferring it to younger members.Behind this proper educational policy and strategic development plans have not been implemented to cope local/indigenous knowledge into practices.Findings of the study indicate that indigenous and local knowledge is a precious province resource that can support the process of disaster prevention,preparedness and response in cost-effective disaster risk reduction.Therefore,policy framework has to prime focus to integrate indigenous and local knowledge,wisdom and skills into mainstream educational programs in order to transfer science into policy and education(words)into practice.

关键词： Multihazard Indigenous knowledge Location-specific Innovative practice Indigenous communities Science to policy

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