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21.
Mycorrhizoremediation an enhanced form of phytoremediation 总被引:2,自引:0,他引:2
Khan AG 《Journal of Zhejiang University. Science. B》2006,7(7):503-514
Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi (AMF) are universal and ubiquitous rhizosphere mi- croflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal (HM) contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. Ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial biotechnology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation. 相似文献
22.
Kathleen Cash Sharful Islam Khan Hashima-E-Nasreen Abbas Bhuiya Sadia Chowdhury A. Mushtaque R. Chowdhury 《Sex education》2013,13(1):43-57
Most people in Bangladesh are rural, poor and underprivileged. The incidence of sexual disease has increased, but little has been done to educate rural people about sexual and reproductive health. In 1997, a sexual and reproductive health project was initiated within a collaborative research agreement between the International Centre for Diarrhoeal Disease Research (ICDDR,B) and the Bangladesh Rural Advancement Committee (BRAC), an indigenous non-governmental organization which pursues integrated rural development strategies. Qualitative in-depth interviews with 65 different women, men, boys and girls revealed significant sexual health problems and a lack of knowledge of sexual and reproductive health. The interviews were transformed into composite problem-solving picture stories and information about sexual and reproductive health. Stories mirrored respondents' interpretations of sexual behavior. Those who had achieved or ascribed legitimacy to talk about sex, e.g. traditional health providers, were trained to utilize the methods and materials. Qualitative evaluations revealed important changes in health providers' self-confidence, business and personal interactions as well as changes in clients' behavior. This project found that sexual and reproductive health education can be integrated into indigenous health activities if the sociocultural context in which sex, relationships, risks, diseases and communication occur is reflected in a program's content and methods. Unquestionably, there is a great need for sex education in rural Bangladesh. 相似文献
23.
24.
Jie Mei Aminul Islam Abidalrahman Moh’d Yajing Wu Evangelos Milios 《Information processing & management》2018,54(6):874-887
Modern OCR engines incorporate some form of error correction, typically based on dictionaries. However, there are still residual errors that decrease performance of natural language processing algorithms applied to OCR text. In this paper, we present a statistical learning model for post-processing OCR errors, either in a fully automatic manner or followed by minimal user interaction to further reduce error rate. Our model employs web-scale corpora and integrates a rich set of linguistic features. Through an interdependent learning pipeline, our model produces and continuously refines the error detection and suggestion of candidate corrections. Evaluated on a historical biology book with complex error patterns, our model outperforms various baseline methods in the automatic mode and shows an even greater advantage when involving minimal user interaction. Quantitative analysis of each computational step further suggests that our proposed model is well-suited for handling volatile and complex OCR error patterns, which are beyond the capabilities of error correction incorporated in OCR engines. 相似文献
25.
In this paper, inverse solutions are obtained for the class of 2D steady incompressible couple stress fluid flows. This class consists of flows for which the vorticity distribution is given by △^2ψ=ψ+f(x,y). The solutions are obtained by applying the inverse method, which makes certain hypotheses regarding the form of the velocity field and pressure but without making any regarding the boundaries of the domain occupied by the fluid. Inverse solutions are derived for three different forms of f(x,y). 相似文献
26.
Ali Shoukot Sarker Md Fouad Hossain Islam M. Saiful Islam Md Kabirul Al Mahmud Rafi 《Tertiary Education and Management》2021,27(2):91-106
Tertiary Education and Management - This study examines how students from rural areas in Bangladesh face particular challenges in adapting to university dormitories in urban areas. There has been... 相似文献
27.
非常感谢中国联合国教科文组织全国委员会的盛情邀请,对于联合国教科文组织每位成员细致人微的工作,我都赞叹不已。在此,非常感谢你们如此出色的工作,同时与这样的团队及成员合作我感到非常愉快,而且常受益匪浅。我已有七八年的时间没有从事开放与远程学习领域的工作,但我确信这个领域已经取得了长足的发展,因此站在这里我感到有些不安,报告中的不妥之处还请大家谅解。 相似文献
28.
We report findings from a cross-institutional investigation testing the applicability of a new concept, ‘satisfied settling’, which describes the ways in which students are unconsciously ‘settling for less’ in terms of their university experiences. The context of exploration for this article was that of Muslim students’ experiences as a critical area which has received little previous focus. Our results describe a staged cognitive process undertaken by students to subconsciously excuse institutional failures to support their religious needs by settling for lower levels of satisfaction. The ‘counter stories’ told by 19 Muslim students (via semi-structured interviews) detail how their voices are heard or silenced around the deep importance of religious provisions in their university experiences. Satisfied settling was ultimately found to translate across institutional contexts, and the applicability of the concept is discussed in extending to other marginalised student groups. 相似文献
29.
Farhana Zahir Shameem J Rizvi Soghra K Haq Rizwan H Khan 《Indian journal of clinical biochemistry : IJCB》2006,21(2):149-152
Mercury pollution and acute neurotoxicity of mercury is well known. The recent reports suggest the adverse effect of low dose
mercury, though the available literature is still silent on its mechanism. This study was therefore undertaken to probe the
effect of low dose methyl mercury induced heavy metal toxicity on free radical stress and its impact on behaviour of male
albino rats. Male albino rats were exposed to 1 mg/kg body wt of methylmercury chloride for seven days, on day 8 they were
tested for motor and memory functions. They were sacrificed later for biochemical estimations for rate of lipid peroxidation,
nucleic acids, proteins in cerebrum, cerebellum and brain stem. There was an increase in the rate of lipid peroxidation showing
methyl mercury induced free radical stress. The motor and memory functions demonstrated a clear decline, besides there was
a lowering in the levels of nucleic acids and proteins as compared to controls. The results are important in view of recent
reports that methyl mercury induced free radical stress results in early ageing and may serve as an initiating factor more
specifically for neurodegenerative disorders like Alzeihemer's disease and dementias. The current findings support the notion
that incorporating dietary antioxidants like curcumin, ascorbic acid and α-tocopherol in routine diet from early age may help
combat the risk of developing such disorders in ensuing years. 相似文献
30.
We report physicochemical characteristics of various kinds of liquid milk commercially available in Pakistan in comparison with those of fresh natural milk from animals. Milk samples were collected from local markets at Peshawar, Pakistan,and analyzed for their physical features, including moisture, total solids, specific gravity, conductivity, viscosity and titratable acidity (lactic acid equivalent), and chemical components and macro-minerals, including total protein, casein, lactose, ash and minerals (Na, K and Mg). These items were compared with the physicochemical characteristics of the fresh natural milk samples from buffalo, cow and goat. The results were also compared with reported nutritional quality of milk from various countries and World Health Organization (WHO) standards. We found that all the physical features and chemical components of commercially available milk in Pakistan markets meet WHO's requirements, except for Na, K, Ca and Mg, which are below the standards. 相似文献