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Distribution, health and ecological risk assessments of trace elements in Nigerian oil sands
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作者 Odunayo T.Ore Festus M.Adebiyi 《Acta Geochimica》 EI CAS CSCD 2024年第1期59-71,共13页
The Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. I... The Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. In the present study, we investigated the distribution pattern of 18trace elements(including biophile and chalcophile elements) as well as the estimated risks associated with exposure to these elements. The results of the study indicated that Fe was the most abundant element, with a mean concentration of 22,131 mg/kg while Br had the lowest mean concentration of 48 mg/kg. The high occurrence of Fe and Ti suggested a possible occurrence of ilmenite(Fe TiO_(3)) in the oil sands. Source apportionment using positive matrix factorization showed that the possible sources of detected elements in the oil sands were geogenic, metal production, and crustal. The contamination factor, geo-accumulation index, modified degree of contamination, pollution load index, and Nemerow pollution index indicated that the oil sands are heavily polluted by the elements. Health risk assessment showed that children were relatively more susceptible to the potentially toxic elements in the oil sands principally via ingestion exposure route(HQ > 1E-04). Cancer risks from inhalation are unlikely due to CR < 1E-06 but ingestion and dermal contact pose severe risks(CR > 1E-04). The high concentrations of the elements pose serious threats due to the potential for atmospheric transport, bioaccessibility, and bioavailability. 展开更多
关键词 Biophile Chalcophile Oil sand Risk assessment Trace element
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Techno-economic and Environmental Assessments of SAF from Bioamss:An Review
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作者 MAHMOOD T.M.N.Saeed PANG Shusheng CHEN Qiang 《林产化学与工业》 CAS CSCD 北大核心 2024年第5期29-51,共23页
This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternati... This review presents a comprehensive techno-economic and life-cycle assessment of sustainable aviation fuel(SAF)production from biomass.The critical need for transitioning towards environmentally sustainable alternatives for liquid fuel and aviation industry is first discussed.Key insights encompass the evolutionary progression of biofuel production from first-generation to second-generation biofuels,with a focus on utilizing non-food sources like woody biomass for enhanced sustainability.Available data from the literature on techno-economic assessments of various SAF production pathways are analyzed including production costs,conversion efficiency,and scalability.Moreover,results of lifecycle assessments associated with different SAF production pathways are presented,providing essential insights for decision-making processes.The challenges of scaling up woody biomass-based SAF production are discussed based on the assessment results,and recommendations are proposed to steer stakeholders towards a greener and more sustainable trajectory for aviation operations. 展开更多
关键词 sustainable aviation fuel woody biomass production costs minimum fuel selling price lifecycle assessment greenhouse gas emissions climate change
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Behavior analysis and formative assessments in online oral medicine education during the COVID-19 pandemic
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作者 Jia-Jia Ye Ye-Ke Zhao +3 位作者 Zhi-Sheng Teng Hui-Wu Ye Qin Yuan Xin Nie 《World Journal of Clinical Cases》 SCIE 2023年第21期5063-5072,共10页
BACKGROUND During the coronavirus disease 2019(COVID-19)pandemic,traditional teaching methods were disrupted and online teaching became a new topic in education reform and informatization.In this context,it is importa... BACKGROUND During the coronavirus disease 2019(COVID-19)pandemic,traditional teaching methods were disrupted and online teaching became a new topic in education reform and informatization.In this context,it is important to investigate the necessity and effectiveness of online teaching methods for medical students.This study explored stomatology education in China to evaluate the development and challenges facing the field using massive open online courses(MOOCs)for oral medicine education during the pandemic.AIM To investigate the current situation and challenges facing stomatology education in China,and to assess the necessity and effectiveness of online teaching methods among medical students.METHODS Online courses were developed and offered on personal computers and mobile terminals.Behavioral analysis and formative assessments were conducted to evaluate the learning status of students.RESULTS The results showed that most learners had already completed MOOCs and achieved better results.Course behavior analysis and student surveys indicated that students enjoyed the learning experience.However,the development of oral MOOCs during the COVID-19 pandemic faced significant challenges.CONCLUSION This study provides insights into the potential of using MOOCs to support online professional learning and future teaching innovation,but emphasizes the need for careful design and positive feedback to ensure their success. 展开更多
关键词 Oral medicine COVID-19 Epidemic prevention and control Online education Behavior analysis Formative assessments
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Is big team research fair in national research assessments? The case of the UK Research Excellence Framework 2021
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作者 Mike Thelwall Kayvan Kousha +4 位作者 Meiko Makita Mahshid Abdoli Emma Stuart Paul Wilson Jonathan Levitt 《Journal of Data and Information Science》 CSCD 2023年第1期9-20,共12页
Collaborative research causes problems for research assessments because of the difficulty in fairly crediting its authors.Whilst splitting the rewards for an article amongst its authors has the greatest surface-level ... Collaborative research causes problems for research assessments because of the difficulty in fairly crediting its authors.Whilst splitting the rewards for an article amongst its authors has the greatest surface-level fairness,many important evaluations assign full credit to each author,irrespective of team size.The underlying rationales for this are labour reduction and the need to incentivise collaborative work because it is necessary to solve many important societal problems.This article assesses whether full counting changes results compared to fractional counting in the case of the UK’s Research Excellence Framework(REF)2021.For this assessment,fractional counting reduces the number of journal articles to as little as 10%of the full counting value,depending on the Unit of Assessment(UoA).Despite this large difference,allocating an overall grade point average(GPA)based on full counting or fractional counting gives results with a median Pearson correlation within UoAs of 0.98.The largest changes are for Archaeology(r=0.84)and Physics(r=0.88).There is a weak tendency for higher scoring institutions to lose from fractional counting,with the loss being statistically significant in 5 of the 34 UoAs.Thus,whilst the apparent over-weighting of contributions to collaboratively authored outputs does not seem too problematic from a fairness perspective overall,it may be worth examining in the few UoAs in which it makes the most difference. 展开更多
关键词 COLLABORATION Research assessment REF REF2021 Research quality SCIENTOMETRICS
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Importance of Public Engagement in Environmental Impact Assessments (EIAs) and the Benefits of Stakeholder Involvement in Project Design, Environmental Soundness, and Social Acceptability
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作者 Samuel Adu Randy Amponsah +1 位作者 Samuel Antwi Peter Mensah 《Journal of Environmental Protection》 2023年第11期919-931,共13页
The paper discusses the importance of public engagement in environmental impact assessments (EIAs) and the benefits of stakeholder involvement in project design, environmental soundness, and social acceptability. It h... The paper discusses the importance of public engagement in environmental impact assessments (EIAs) and the benefits of stakeholder involvement in project design, environmental soundness, and social acceptability. It highlights the negative repercussions of mining activities in Ghana, including health consequences such as skin conditions, fever, coughs, diarrhea, malaria, and catarrh, as well as HIV/AIDS infection among those engaged in or connected to prostitution in mining towns. The environmental effects of mining in Ghana include noise pollution from heavy trucks, contamination of water bodies with chemicals from mineral refining, pollution of agricultural soils leading to reduced food productivity, and wildlife depletion from deforestation. The activities of small-scale miners, particularly those engaged in illicit mining, have a negative impact on water quality and increase the cost of water treatment for public consumption. Mining operations have detrimental effects on the social, cultural, and natural ecosystems in Ghana, affecting the quality of life of local communities. The study takes into consideration the impact of mining activities on the environment and natural resources in Ghana, as these are vital to the livelihoods of Ghanaian communities. Stakeholders in Tarkwa claim that mining operations have distorted the natural path of the river, leading to excessive pollution and making the water unfit for consumption. Ghana’s economy depends heavily on mining, which also contributes significantly to GDP and generates jobs for a large number of people. But mining also has a lot of negative repercussions, the effects of mining extend beyond the mineralized zone initially explored, highlighting the need to consider the environmental impact at every phase of the mining process. 展开更多
关键词 Sustainable Mineral Production Mining Environmental Sustainability Environmental Impact Assessment
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The impact of farmers’ assessments of risk management strategies on their adoption willingness 被引量:1
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作者 SHANG Yan XIONG Tao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第12期3323-3338,共16页
Farmers'assessments of risk management strategies and how the assessments influence their willingness to adopt these strategies are poorly understood.This study conducts a structured survey of 469 farmers to inves... Farmers'assessments of risk management strategies and how the assessments influence their willingness to adopt these strategies are poorly understood.This study conducts a structured survey of 469 farmers to investigate how farmers assess both crop insurance and crop price insurance,the impact of the assessments on their adoption willingness,and in particular,the differences in assessments and adoption willingness between crop insurance and crop price insurance.Empirical results show that farmers’assessments on crop insurance can be significantly improved through communication and experience.The most effective way to improve farmers'assessments on crop price insurance is providing adequate information about the insurance products.Furthermore,farmers'adoption willingness would be enhanced by improved assessment of both crop yield and crop price insurance.This study provides the first empirical evidence that farmers have limited information to assess insurance,which significantly influences their willingness to adopt.This finding reflects that the dissemination of insurance policies,the effectiveness of insurance,and the availability of insurance services significantly enable farmers'ability to assess risk management strategies,which potentially increases farmers'willingness to adopt insurance. 展开更多
关键词 assessments adoption willingness crop insurance crop price insurance protection motivation theory(PMT)
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Reflections on Tools and Methods for Differentiated Assessments of Individual Scientists, Groups of Scientists and Scientific Journals 被引量:1
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作者 Ronald Rousseau Xiaolin Zhang 《Journal of Data and Information Science》 CSCD 2019年第3期1-5,共5页
Requirements for research assessments There are huge differences in mission, emphasis, inherent capability, and targeted utilization of research among scientific institutions. Hence, when it comes to assessments, a on... Requirements for research assessments There are huge differences in mission, emphasis, inherent capability, and targeted utilization of research among scientific institutions. Hence, when it comes to assessments, a one-size-fits-all approach cannot meet the goal(s) of these assessments. Probably even larger differences exist between individuals, research teams and departments. 展开更多
关键词 REFLECTIONS TOOLS and METHODS DIFFERENTIATED assessments of INDIVIDUAL Scientists
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Risk assessments of debris flow based on improved analytic hierarchy process and efficacy coefficient method 被引量:2
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作者 LIU Guochao LI Guangjie YANG Lina 《Global Geology》 2012年第3期231-236,共6页
In order to evaluate the danger of debris flow properly, eight factors were selected as the risk assess- ment indexes of the debris flow, namely the vertical slope, valley relative difference, hillside slope, area of ... In order to evaluate the danger of debris flow properly, eight factors were selected as the risk assess- ment indexes of the debris flow, namely the vertical slope, valley relative difference, hillside slope, area of ba- sin, loose solid material reserves, the path length of sediment supply probability, silting and scouring derrieking and vegetation coverage. The improved Analytic Hierarchy Process ( AHP ) method was used to obtain the weights of the factors; and the efficacy coefficient method was adopted to evaluate the risks of six typical debris flow gullies. According to the research, the improved AHP method not only avoids the subjectivity in the indi- vidual factor valuation by comparing two factors of each layer, but also makes the subsequent consistency check unnecessary. 展开更多
关键词 improved AI-IP method efficacy coefficient method debris flow risk assessments
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Health Professionals’ Attitudes towards Electronic Psychosocial Assessments in Youth Mental Healthcare
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作者 Sally Bradford Debra Rickwood Douglas Boer 《Health》 2014年第14期1822-1833,共12页
Psychosocial assessments can help mental health professionals establish good therapeutic relationships while simultaneously conducting holistic assessments of their young clients. Using technology to conduct assessmen... Psychosocial assessments can help mental health professionals establish good therapeutic relationships while simultaneously conducting holistic assessments of their young clients. Using technology to conduct assessments may increase disclosure by young people;however, the uptake of new technologies into current face-to-face practice has been slow. In the current study, we were interested in exploring the attitudes of mental health workers to using an electronic psychosocial assessment tool (e-tool) within face-to-face service delivery with adolescents and young adults. An exploratory design was used to identify and qualitatively describe the views of 46 mental health workers from services across the ACT and Victoria, Australia. Data were coded using an inductive thematic approach. Comments indicated that mental health workers held both positive and negative views about the e-tool. Some participants believed that it would allow disclosure to occur in a stepped process, normalize questions, give youth greater input, and be time efficient. However, the majority believed that the e-tool would infringe on their work because they needed to respond to their clients immediately, it would not provide an accurate representation of the client, young people did not have the necessary capabilities to engage in the process, they would miss non-verbal cues from the young person, and they were more likely to gain information from organic conversations. The results suggest that many mental health professionals may be fearful of incorporating new technologies in current practice. Specific training and supportive implementation guidelines must be developed to support use of these new technologies and change practice. 展开更多
关键词 PSYCHOSOCIAL assessments YOUNG PEOPLE Information Communication Technologies MENTAL Healthcare
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Calculations of Radiations Attenuation and Dose Assessments of Tunnels Passing under Water Canals
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作者 Mohamed Farahat Moustafa Aziz 《Journal of Environmental Science and Engineering(A)》 2015年第11期607-613,共7页
Most of the developed countries have used their tunnels as protective structures (public nuclear shelters) in case of nuclear emergencies to protect their citizens from the dangerous effects of nuclear weapons. The ... Most of the developed countries have used their tunnels as protective structures (public nuclear shelters) in case of nuclear emergencies to protect their citizens from the dangerous effects of nuclear weapons. The research aims to explain how to use tunnels to protect some people from neutrons and gamma rays and account the required safe depth. The computer code (MCNP5) is used at this model for such tunnel to account attenuation of both neutrons and gamma rays passing through the canal water, sand, soil and reinforced concrete wall layers. The last one (thickness 105 cm) constructed the tunnel construction. Also, the computer code is used to account the dose inside the tunnel, and account (neutron) dose, (neutron, gamma) dose, prompt (gamma) dose, total (gamma) dose and total (neutron + gamma) dose estimated by μsv/h, at different depths from the water surface level (depths 200 cm, 500 cm, 1,000 cm, 1,600 cm, 2,200 cm, 2,600 cm, 2,800 cm, 3,400 cm, 3,700 cm, 4,000 cm and 4,600 cm). Then, account these doses for three bombs (its intensity 20 KT, 100 KT and 1,000 KT). 展开更多
关键词 Calculations of radiations radiations attenuation dose assessments TUNNELS water canals.
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Attitudes to Group Assessments: Prospective Psychotherapists’ Experiences of Being Assessed by Fellow Students
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作者 Anette Jervelycke Billy Larsson Torsten Norlander 《Open Journal of Medical Psychology》 2017年第3期179-196,共18页
Background: The guidance of prospective therapists focused on Cognitive Behavioral Therapy (CBT) is most often made by groups of four students. However, learning therapist skills is a sensitive process that will be af... Background: The guidance of prospective therapists focused on Cognitive Behavioral Therapy (CBT) is most often made by groups of four students. However, learning therapist skills is a sensitive process that will be affected by the processes which occur within the group. Objective: The aim was to examine prospective psychotherapists’ attitudes to group assessments based on the revised version of the Cognitive Therapy Scale (CTS-R). Method: Participants were 56 students with an average age of 45.65 years (range = 31 - 64). They were recruited from psychotherapy training at the Gothenburg University and the Evidens University College in Sweden. A questionnaire was constructed in which the questions were answered by check on visual analogue scales (VAS). Results: A majority of students consisting of 38 participants (68%) had a very positive approach to group assessments, while a minority of 18 participants (32%) was more negative. Most crucial for how to answer the question of group assessments was whether they considered themselves as fairly evaluated by their student colleagues within the group and whether or not only the supervisor should make the assessments. The view of group assessments (negative or positive) was not related to age, gender, and level of education in CBT or profession. In addition, both groups had a very positive view of both the CTS-R and the supervisors. Conclusion: It was concluded that more studies with the same focus are needed to determine the extent to which the results are generalizable. 展开更多
关键词 CBT Competences CTS-R Evaluation Process Group assessments PROSPECTIVE Psychotherapists
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Assessments of America's Global Strategy
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《Contemporary International Relations》 2003年第9期1-1,共1页
Ever since Bush entered the White house, especially after 9/11 events, America has successively published series of strategic documents, such as the Nuclear Posture Review, Quadrennial Defense Review, National Securit... Ever since Bush entered the White house, especially after 9/11 events, America has successively published series of strategic documents, such as the Nuclear Posture Review, Quadrennial Defense Review, National Security Strategy of the United States of America, National Strategy for Combating Terrorism, National Strategy to Combat Weapons of Mass Destruction. After its unilateralist practices gained points military and lost points politically in the Afghan war and the Iraq war, the multi-lateralist posture on dealing with 展开更多
关键词 of assessments of America’s Global Strategy for
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Comparison of different nutritional assessments in detecting malnutrition among gastric cancer patients 被引量:59
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作者 Seung Wan Ryu In Ho Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第26期3310-3317,共8页
AIM: To evaluate the prevalence of preoperative and postoperative malnutrition and the relationships between objective and subjective nutritional assessment of gastric cancer patients. METHODS: From October 2005 to Ju... AIM: To evaluate the prevalence of preoperative and postoperative malnutrition and the relationships between objective and subjective nutritional assessment of gastric cancer patients. METHODS: From October 2005 to July 2006, we studied 80 patients with no evidence of recurrent disease and no loss to follow-up after curative surgery for gastric cancer. In this group, 9 patients underwent total gastrectomy and 71 patients subtotal gastrectomy. At admission, 6 and 12 mo after surgery, the patients were assessed on the subjective global assessment (SGA), nutritional risk screening (NRS-2002), nutritional risk index (NRI) and by anthropometric measurements and laboratory data. Differences between the independent groups were assessed with the Student's t test and oneway analysis of variance. Spearman's rank correlation coefficients were calculated to evaluate the association between the scores and variables. RESULTS: The prevalence of malnutrition at admissionwas 31% by SGA and 43% by NRS-2002. At admission, the anthropometric data were lower in the malnourished groups defined by the SGA and NRS-2002 assessments, but did not differ between the groups using the NRI assessment. Body weight (BW), body mass index (BMI), triceps skin fold and midarm circumference were significantly reduced, but the total lymphocyte count, albumin, protein, cholesterol and serum iron levels did not decrease during the postoperative period. Six months after surgery, there was a good correlation between the nutritional assessment tools (SGA and NRS-2002) and the other nutritional measurement tools (BW, BMI, and anthropometric measurements). However, 12 mo after surgery, most patients who were assessed as malnourished by SGA and NRS-2002 had returned to their preoperative status, although their BW, BMI, and anthropometric measurements still indicated a malnourished status. CONCLUSION: A combination of objective and subjective assessments is needed for the early detection of the nutritional status in case of gastric cancer patients after gastrectomy. 展开更多
关键词 GASTRECTOMY MALNUTRITION Nutritional assessment Nutritional risk screening Postoperative follow up Subjective global assessment
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Surface water quality and potential health risk assessments in Changsha-Zhuzhou-Xiangtan section of Xiangjiang River, China 被引量:7
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作者 JIANG Dong-yi YANG Jin-qin +3 位作者 WANG Yun-yan LIAO Qi LONG Zhe ZHOU San-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3252-3260,共9页
The Changsha-Xiangtan-Zhuzhou City Group is a heavy industrial district and accepted as the serious pollution area in the Xiangjiang River basin.In this study,7 metals(Pb,Hg,Cd,As,Zn,Cu and Se)and the river water qual... The Changsha-Xiangtan-Zhuzhou City Group is a heavy industrial district and accepted as the serious pollution area in the Xiangjiang River basin.In this study,7 metals(Pb,Hg,Cd,As,Zn,Cu and Se)and the river water quality parameters including pH,dissolved oxygen(DO),Escherichia coli(E.coli),potassium permanganate index(CODMn),dichromate oxidizability(CODCr),five-day biochemical oxygen demand(BOD5),ammonia nitrogen(NH4+-N),total nitrogen(TN),total phosphorus(TP)and fluoride(F)in 18 sampling sites of the Changsha-Xiangtan-Zhuzhou section are monthly monitored in 2016,which is the year to step into the second stage of the“Xiangjiang River Heavy Metal Pollution Control Implementation Plan”.It is found that E.coli,TN and TP are the main pollutants in the Changsha-Zhuzhou-Xiangtan section,and the pollution of heavy metal is not serious but As with potential risk to local people especially children should be concerned.In addition,Xiangtan city is mainly featured with heavy metal pollution,while Zhuzhou and Changsha city are both featured with other pollutants from municipal domestic sewage. 展开更多
关键词 Xiangjiang River surface water heavy metal water quality assessment human health risk assessment
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Multi-mycotoxin exposure and risk assessments for Chinese consumption of nuts and dried fruits 被引量:5
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作者 WANG Yu-jiao NIE Ji-yun +3 位作者 YAN Zhen LI Zhi-xia CHENG Yang Saqib Farooq 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第7期1676-1690,共15页
In this study, 15 mycotoxins were detected in 233 nut and dried fruit samples from China. The 15 mycotoxins included aflatoxins (AFs: AFB1, AFB2, AFG1 and AFG2), trichothecene toxins (TCs: T-2, ZEA, ENA, ENA1, EN... In this study, 15 mycotoxins were detected in 233 nut and dried fruit samples from China. The 15 mycotoxins included aflatoxins (AFs: AFB1, AFB2, AFG1 and AFG2), trichothecene toxins (TCs: T-2, ZEA, ENA, ENA1, ENB, ENB1 and BEA), Alternaria toxins (ATs: TEN, AOH and AME) and ochratoxin A (OTA). The mycotoxins were detected in 47.6% of the samples and all 15 of the mycotoxins were found. Two samples were positive for AFB1 and exceeded the maximum tolerable levels allowed in China. The contamination levels of the mycotoxins found in nuts, dried jujubes, raisins, dried figs and dried Iongans were in the ranges of 0.1-462.7, 0.2-247.3, 0.8-10.1,0.2-384.1 and 0.1-89.2 μg kg^-1, respectively. Dried figs (80.0%) had the highest incidence of mycotoxins, followed by dried Iongans (60.0%), dried jujubes (57.1%), nuts (43.6%) and raisins (26.7%). The estimated daily intake (EDI) values of each individual mycotoxin and all of the mycotoxins collectively were calculated by both the deterministic approach (DA) and the probability approach (PA). For risk characterization, dietary exposure to TCs, ATs and OTA through consumption of nuts and dried fruits according to both approaches, showed no health risk to Chinese adults by exposure to either individual mycotoxins or in combination. To the best of our knowledge, this is the first work in which risk assessment of multimycotoxins is performed, specifically including the emerging ENNs and BEA, in nuts and dried fruits of China. 展开更多
关键词 mycotoxins risk assessment deterministic analysis probabilistic analysis NUTS dried fruits
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Impacts of distorted fishery statistical data on assessments of three surplus production models 被引量:3
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作者 王迎宾 郑基 王征 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期270-276,共7页
We evaluated the effect of various error sources in fishery harvest/effort data on the maximum sustainable yield (MSY) and corresponding fishing effort (EMsv) using Monte Carlo simulation analyses. A high coeffici... We evaluated the effect of various error sources in fishery harvest/effort data on the maximum sustainable yield (MSY) and corresponding fishing effort (EMsv) using Monte Carlo simulation analyses. A high coefficient of variation (CV) of the catch and effort values biased the estimates of MSY and EMsv. Thus, the state of the fisheries resource and its exploitation was overestimated. We compared the effect using three surplus production models, Hilborn-Waters (H-W), Schnute, and Prager models. The estimates generated using the H-W model were significantly affected by the CV. The Schnute model was least affected by errors in the underlying data. The CVof the catch data had a greater impact on the assessment than the CV of the fishing effort. Similarly, the changes in CV had a greater impact on the estimated maximum sustainable yield (MSY) than on the corresponding estimate of fishing effort (EMsY). We discuss the likely effect of these biases on management efforts and provide suggestions for the improvement of fishery evaluations. 展开更多
关键词 distorted data Monte Carlo simulation ERROR stock assessment
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Comparative carbon emission assessments of recycled and natural aggregate concrete: Environmental influence of cement content 被引量:3
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作者 Marian Sabǎu Dan V.Bompa Luis F.O.Silva 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第6期66-75,共10页
This work examines the environmental and geochemical impact of recycled aggregate concrete production with properties representative for structural applications.The environmental influence of cement content,aggregate ... This work examines the environmental and geochemical impact of recycled aggregate concrete production with properties representative for structural applications.The environmental influence of cement content,aggregate production,transportation,and waste landfilling is analysed by undertaking a life cycle assessment and considering a life cycle inventory largely specific for the region.To obtain a detailed insight into the optimum life cycle parameters,a sensitivity study is carried out in which supplementary cementitious materials,different values of natural-to-recycled aggregate content ratio and case-specific transportation distances were considered.The results show that carbon emissions were between 323 and 332 kgCO_(2)e per cubic metre of cement only natural aggregate concrete.These values can be reduced by up to 17%by replacing 25%of the cement with fly ash.By contrast,carbon emissions can increase when natural coarse aggregates are replaced by recycled aggregates in proportions of 50%and 100%,and transportation is not included in analysis.However,the concrete with 50%recycled aggregate presented lower increase,only 0.3%and 3.4%for normal and high strength concrete,respectively.In some cases,the relative contribution of transportation to the total carbon emissions increased when cement was replaced by fly ash in proportions of 25%,and case-specific transportation distances were considered.In absolute values,the concrete mixes with 100%recycled aggregates and 25%fly ash had lower carbon emissions than concrete with cement and natural aggregates only.Higher environmental benefits can be obtained when the transportation distances of fly ash are relatively short(15–25 km)and the cement replacement by fly ash is equal or higher than 25%,considering that the mechanical properties are adequate for practical application.The observations from this paper show that recycled aggregate concrete with strength characteristics representative for structural members can have lower carbon emissions than conventional concrete,recommending them as an alternative to achieving global sustainability standards in construction. 展开更多
关键词 Life cycle assessment Recycled aggregate Natural aggregate Transportation distance OpenLCA
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The role of hazard vulnerability assessments in disaster preparedness and prevention in China 被引量:3
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作者 Yan Du Yi-bo Ding +1 位作者 Zi-xiong Li Guang-wen Cao 《Military Medical Research》 SCIE CAS 2015年第4期228-234,共7页
China is prone to disasters and escalating disaster losses. Effective disaster mitigation is the foundation for efficient disaster response and rescue and for reducing the degree of hazardous impacts on the population... China is prone to disasters and escalating disaster losses. Effective disaster mitigation is the foundation for efficient disaster response and rescue and for reducing the degree of hazardous impacts on the population. Vulnerability refers to the population's capacity to anticipate, cope with, and recover from the impact of a hazardous event. A hazard vulnerability assessment(HVA) systematically evaluates the damage that could be caused by a potential disaster, the severity of the impact, and the available medical resources during a disaster to reduce population vulnerability and increase the capacity to cope with disasters. In this article, we summarized HVA team membership, content(disaster identification, probability and consequences), and methods and procedures for an HVA that can be tailored to China's needs. We further discussed the role of epidemiology in an HVA. Disaster epidemiology studies the underlying causes of disasters to achieve effective disaster prevention and reduction. In addition, we made several recommendations that are already in practice in developed countries, such as the U.S., for future implementation in China and other developing countries. An effective HVA plan is crucial for successful disaster preparedness, response, and recovery. 展开更多
关键词 VULNERABILITY Hazard vulnerability assessment Disaster epidemiology Disaster preparedness
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Impact Assessments of Transgenic cry1Ab Rice on the Population Dynamics of Five Non-Target Thrips Species and Their General Predatory Flower Bug in Bt and Non-Bt Rice Fields Using Color Sticky Card Traps 被引量:9
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作者 Akhtar Zunnu Raen YE Gong-yin +4 位作者 LU Zeng-bin CHANG Xue SHEN Xiao-jing PENG Yu-fa HU Cui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第10期1807-1815,共9页
A 2-yr field study was conducted to assess the effects of transgenic japonica rice(KMD1 and KMD2) with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densiti... A 2-yr field study was conducted to assess the effects of transgenic japonica rice(KMD1 and KMD2) with a synthetic cry1 Ab gene from Bacillus thuingiensis Berliner on population dynamics and seasonal average densities of five thrips species including Stenchaetothrips biformis(Bagnall),Frankliniella intonsa(Trybom),F.tenuicornis(Uzel),Haplothrips aculeatus(Fabricius),Haplothrips tritici(Kurd) and their general predatory flower bug,Orius similis Zheng as compared to the parental control rice line using the white,blue and yellow sticky card traps.Population dynamics and seasonal average densities of these five thrips species and their general predatory flower bug were not significantly affected by rice type.Additionally,the white sticky card trap was suggested to be the most suitable for monitoring the population of these five thrips species and their general predator.These results show that our tested Bt rice lines do not interrupt the population of non-target thrips species and their general predatory flower bug in the field,and also cannot result in more occurrence of these thrips species in the rice ecosystem. 展开更多
关键词 rice thrips predatory flower bug non-target effects Bt rice risk assessment
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Structuring Probability Assessments 被引量:3
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作者 Warren Richard Hughes 《Chinese Business Review》 2020年第5期171-177,共7页
A probability assessment framework is outlined that enables decision-makers to determine a probability distribution over possible events or scenarios they could face in the future.The methodology of the analytic hiera... A probability assessment framework is outlined that enables decision-makers to determine a probability distribution over possible events or scenarios they could face in the future.The methodology of the analytic hierarchy process can be utilized in the procedures.Bayesian revision accounting for new developments can be used to calculate posterior probabilities using the same procedures. 展开更多
关键词 decision theory probability assessment analytic hierarchy process Bayesian revision
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