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141.
Phytoremediation of heavy metal polluted soils and water:Progresses and perspectives 总被引:4,自引:0,他引:4
Environmental pollution affects the quality of pedosphere, hydrosphere, atmosphere, lithosphere and biosphere. Great efforts
have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources. Phytoremediation,
being more cost-effective and fewer side effects than physical and chemical approaches, has gained increasing popularity in
both academic and practical circles. More than 400 plant species have been identified to have potential for soil and water
remediation. Among them, Thlaspi, Brassica, Sedum alfredii H., and Arabidopsis species have been mostly studied. It is also expected that recent advances in biotechnology will play a promising role in
the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the
higher biomass producing cultivated species in the times to come. This paper attempted to provide a brief review on recent
progresses in research and practical applications of phytoremediation for soil and water resources.
Project supported by the Higher Education Commission, Government of Pakistan for the faculty training under the R & D Project
“Strengthening Department of Soil Science and Soil and Water Conservation” at the University of Florida, USA, a grant from
the St. Lucie River Water Initiative (SFWMD contract No. OT060162), USA, in part, and the Program for Changjiang Scholars
and Innovative Research Team in University (No.IRT0536), China 相似文献
142.
Stephen Wilkins Lan He Li Zhu Mohammad Elmoshnib 《Journal of Higher Education Policy & Management》2018,40(3):256-271
In recent years, domestic demand for MBAs has fallen in most major Western markets but has increased or remained stable in emerging economies such as China and the United Arab Emirates (UAE), which are the two countries globally that host the largest numbers of international branch campuses. Thus, this research aimed to discover why students in China and the UAE still want an MBA. A survey questionnaire was completed by a total of 354 MBA students, at two universities in China and two universities in the UAE. Some of the results were surprising and unexpected. For example, recognition, prestige and networking – all key features in Chinese and Emirati societies – were found not to be key motivators for wanting an MBA. Instead, the desire to acquire knowledge and skills was the strongest motivator among respondents, accounting for 32.4 per cent of variance. This was followed by reasons associated with intrinsic benefits. The findings have implications for institutional strategy, curriculum design, program delivery and the marketing of programs. 相似文献
143.
Mohammad Nazim 《International Information and Library Review》2018,50(1):13-23
This study analyzes the current state of gold Open Access (OA) in India based on papers published in the Web of Science indexed journals. It specifically focuses on research output published in OA journals and examines the difference between gold OA and general research output for papers authored by Indian researchers. In order to analyze the Indian contribution of gold OA literature and compares with other countries, Web of Science?-Core Collection was used. There is an increasing trend of contributing research papers in OA journals by Indian researchers. Among the top 20 publishing countries India ranks 10th place in terms of the general research output, but secures 8th place in terms of gold OA papers. However, India's position in terms of share of gold OA publications is relatively higher than other leading countries of the world. Researchers in India mostly prefer to contribute their gold OA papers in Indian journals rather foreign journals and the proportion of gold OA research output in Clinical, Preclinical, Health, Life Sciences and Physicals Sciences is much higher than other disciplines such as Arts &; Humanities and Social Sciences. Since most of the research output in India is published in local journals, the study suggests further analyses of publications which are not published in Web of Science indexed journals. 相似文献
144.
Mohammad Reza Ghane 《Learned Publishing》2016,29(2):77-82
The references cited in scientific articles are as important as any other part of the paper, because of their usefulness to the scientific community and to abstracting and indexing services and citation databases. I studied inaccuracies in references and in‐text citations in sample of 97 of the 519 peer‐reviewed journals accredited by the Iranian National Commission for Journal Accreditation Policy (Ministry of Research, Science and Technology). The target journals published 2,980 articles with 74,577 cited references and 108,151 in‐text citations. The results showed 36.6% as the average percentage error rate (range 5.6% to 61.3%). The mean number of errors in cited reference and in‐text citations was 2.7 per article, and the mean number of errors per journal was 690. For the entire sample of articles, 4,369 in‐text citations did not match any source in the list of references (4%), and 8,683 cited references did not match any in‐text citation (11.6%). The stakeholders in scholarly communication, especially authors, pay insufficient attention to the accuracy of bibliographic references. Peer‐reviewed journals should encourage the use of standardized journal policies and quality‐control measures regarding peer review, data quality and accuracy. 相似文献
145.
Mohammad Qasem Keith George John Somauroo Lynsey Forsythe Benjamin Brown 《Journal of sports sciences》2019,37(3):306-312
Athlete pre-participation screening is focused on detecting pathological conditions like arrhythmogenic right ventricular cardiomyopathy (ARVC). The diagnosis of ARVC is established by applying the revised 2010 ARVC Task Force Criteria (TFC) that assesses RV structure and function. Some athletes may meet structural TFC without having ARVC but we do not know the consequences for RV function. This study compared RV structural and functional indices in male athletes that meet the structural TFC (MTFC) for ARVC and those that do not (NMTFC). We recruited 214 male elite athletes. All participants underwent 2D, Doppler, tissue Doppler and strain (ε) echocardiography with a focused and comprehensive assessment of the right heart. Athletes were grouped on RV structural data: MTFC n = 34; NMTFC n = 180. Functional data were compared between groups. By selection, MTFC had larger absolute and scaled RV outflow tract (RVOT) diameter compared to NMTFC (P ?0.05) but these athletes did not develop a proportional increase in the RV inflow dimensions. There was no difference in global conventional RV systolic function between both groups however, there was significantly lower global RV ε in athletes that MTFC which can be explained, in part, by the RVOT dimension. 相似文献
146.
Fabio Savoldi Andy W. K. Yeung Ray Tanaka Lisa S. Mohammad Zadeh Carla Montalvao Michael M. Bornstein James K. H. Tsoi 《Anatomical sciences education》2021,14(1):62-70
Learning bone anatomy of the skull is a complex topic involving three-dimensional information. The impact of the use of human dry skulls and cone beam computed tomography (CBCT) imaging was investigated in the teaching of undergraduate dental students. Sixty-four first-year students in the University of Hong Kong were randomly divided into eight groups. Four teaching methods were tested: (1) CBCT followed by standard lecture, (2) CBCT followed by lecture with skulls, (3) standard lecture followed by CBCT, and (4) lecture with skulls followed by CBCT. After each, students were given a multiple-choice questionnaire to assess their objective learning outcome (20 questions) and a questionnaire for their subjective satisfaction (10 statements). Surveys were assessed with Cronbach's alpha, Kendall's tau-b, and principal components analysis. Data were analyzed with Student's t-test and a one-way ANOVA (significance α = 0.05). Standard lecture followed by CBCT showed the highest learning outcome score (81.6% ± 14.1%), but no significant difference was present among four teaching methods. Cone beam computed tomography followed by lecture with skulls scored the highest overall subjective satisfaction (4.9 ± 0.8 out of 6), but no significant difference was present among teaching methods. Nevertheless, students' perception of learning was positively influenced by the use of skulls (P = 0.018). The timing of administration of the CBCT did not affect students' subjective satisfaction or objective learning outcome. Students perceived to learn more by using skulls, but their objective learning outcomes were not significantly affected. A discrepancy seems to exist between students' perception of learning and their effective performance. 相似文献
147.
Improvement of the efficacy of influenza vaccination (H5N1) in chicken by using extract of Cochinchina momordica seed (ECMS) 总被引:1,自引:0,他引:1
Rajput ZI Xiao CW Hu SH Arijo AG Soomro NM 《Journal of Zhejiang University. Science. B》2007,8(5):331-337
Seeds of a Chinese traditional medicine plant, Cochinchina momordica were used in the present study for the improvement of influenza vaccine (HSN 1) in chicken. Crude extraction from Cochinchina momordica seed (ECMS) was obtained by ethanol extraction method. In experiment No. 1, two weeks old chickens were immunized with influenza vaccine (HSN1) alone or combined with ECMS (5, 10, 20, 40 and 80 μg/dose). Serum IgG antibody levels (by ELISA) as well as effects on dally weight gain were measured on 0, 7, 14 and 28th day after immunization. Results revealed that all ECMS groups numerically increased the antibody levels while 10 and 20 μg/dose groups significantly (P〈0.05) enhanced total IgG antibody on day 28, when compared with control. Average daily weight gain was also significantly higher in 20 μg/dose ECMS group. Adjuvant effect was also confirmed in experiment No. 2 when chickens were immunized with 20 μg/dose ECMS and antibody titer was measured through hemagglutination inhibition (HI). It is concluded that ECMS has potential to improve the immune responses and deserve further study as an adjuvant. 相似文献
148.
Seyed Sahand SEBTI Mohammad MASTIANI Hooshyar MIRZAEI Abdolrahman DADVAND Sina KASHANI Seyed Amir HOSSEINI 《浙江大学学报(A卷英文版)》2013,14(5):307-316
A comprehensive numerical study was conducted to investigate heat transfer enhancement during the melting process in a 2D square cavity through dispersion of nanoparticles. A paraffin-based nanofluid containing various volume fractions of Cu was applied. The governing equations were solved on a non-uniform mesh using a pressure-based finite volume method with an enthalpy porosity technique to trace the solid-liquid interface. The effects of nanoparticle dispersion in a pure fluid and of some significant parameters, namely nanoparticle volume fraction, cavity size and hot wall temperature, on the fluid flow, heat transfer features and melting time were studied. The results are presented in terms of temperature and velocity profiles, streamlines, isotherms, moving interface position, solid fraction and dimensionless heat flux. The suspended nanoparticles caused an increase in thermal conductivity of nano-enhanced phase change material (NEPCM) compared to conventional PCM, resulting in heat transfer enhancement and a higher melting rate. In addition, the nanofluid heat transfer rate increased and the melting time decreased as the volume fraction of nanoparticles increased. The higher temperature difference between the melting temperature and the hot wall temperature expedited the melting process of NEPCM. 相似文献
149.
Mohammad Al-Smadi Mahmoud Al-Ayyoub Yaser Jararweh Omar Qawasmeh 《Information processing & management》2019,56(2):308-319
This research presents an enhanced approach for Aspect-Based Sentiment Analysis (ABSA) of Hotels’ Arabic reviews using supervised machine learning. The proposed approach employs a state-of-the-art research of training a set of classifiers with morphological, syntactic, and semantic features to address the research tasks namely: (a) T1:Aspect Category Identification, (b) T2:Opinion Target Expression (OTE) Extraction, and (c) T3: Sentiment Polarity Identification. Employed classifiers include Naïve Bayes, Bayes Networks, Decision Tree, K-Nearest Neighbor (K-NN), and Support-Vector Machine (SVM).The approach was evaluated using a reference dataset based on Semantic Evaluation 2016 workshop (SemEval-2016: Task-5). Results show that the supervised learning approach outperforms related work evaluated using the same dataset. More precisely, evaluation results show that all classifiers in the proposed approach outperform the baseline approach, and the overall enhancement for the best performing classifier (SVM) is around 53% for T1, around 59% for T2, and around 19% in T3. 相似文献
150.
Sadegh Fattahi Mohammad Karimi Alivije Farhang Babamahmoodi Masomeh Bayani Mahmoud Sadeghi Haddad Zavareh Mohsen Asouri Maryam Lotfi Galia Amirbozorgi Haleh Akhavan-Niaki 《Indian journal of clinical biochemistry : IJCB》2018,33(4):467-472
Hepatitis B virus (HBV) infection is a worldwide health concern which is associated with significant morbidity and mortality. Both viral and host factors have a significant effect on infection, replication and pathogenesis of HBV. The aim of this study was to investigate the effect of CYP2E1 and CYP1A1 genetic variants on susceptibility to HBV. 143 individuals including 54 chronic HBV patients and 89 healthy controls were enrolled in the genotyping procedure. rs2031920 and rs3813867 at CYP2E1 as well as rs4646421 and rs2198843 at CYP1A1 loci were studied in all subjects using PCR–RFLP (restriction fragment length polymorphism) analysis. Both variants at CYP2E1 locus were monomorphic in all studied subjects. Genotype frequency of rs4646421 was significantly different between chronic HBV patients and healthy blood donors (P = 0.04, OR 4.31; 95% CI 1.04–17.7). Furthermore, individuals carrying at least one C allele (CC or CT genotypes) for rs4646421 seemed to have a decrease risk of hepatitis in comparison with TT genotype (P = 0.039). Our results showed a relationship between rs4646421 TT genotype (rare genotype) and the risk for developing chronic HBV infection (four times higher). Further studies are needed to examine the role of CYP1A1 polymorphism in susceptibility to chronic HBV infection. 相似文献