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1.
Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects of pollutants from textile wastewater on the anatomy of the plant were studied. Water hyacinth exhibits hydrophytic adaptations which include reduced epidermis cells lacking cuticle in most cases, presence of large air spaces (7∼50 μm), reduced vascular tissue and absorbing structures. Textile waste significantly affected the size of root cells. The presence of raphide crystals was noted in parenchyma cells of various organs in treated plants. Project (No. 30070017) supported by the National Natural Science Foundation of China  相似文献   
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This study is the first to inquire about the factors that influence people’s willingness to allow professional photojournalists to tell their stories through the medium of the photo essay. Guided by Self-Disclosure Theory, in-depth interviews were conducted with the subjects of 15 peer-judged award-winning photo essays. These were drawn from the multiple picture categories of the National Press Photographers Association (NPPA) Monthly Clip Contest, the annual NPPA Best of Photojournalism Contest, and the annual World Press Photo Contest between 2013 and 2017. The topics of the photo essays were sensitive in nature. Analysis reveals support and appreciation amongst photo-essay subjects for the profession of photojournalism. Motivations derived from the sensitivity and professionalism with which each interviewee was initially approached, a need to tell a different side of the story, a desire to inspire others or invoke change, and the memory-keeping and permanence afforded through published professional photojournalism.  相似文献   
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INTRODUCTION Regulation, handling and bioremediation of hazardous materials require an assessment of the risk to some living species other than human being, or assessment of hazard to the entire ecosystem. As- sessment endpoints are values of the ecosystem that are to be protected and are identified early in the analysis. Such endpoints may include life cycle stages of a species and reproductive or growth patterns. Ecosystem risk assessment is at its dawn with this area of environment sci…  相似文献   
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This paper presents an improved model for global sunshine duration estimation. The methodology incorporates geostationary satellite images by including snow cover information, sun and satellite angles and a trend correction factor for seasons, for the determination of cloud cover index. The effectiveness of the proposed methodology has been tested using Meteosat geostationary satellite images in the visible band with a temporal resolution of 1 h and spatial resolution of 2.5 km×2.5 km, for the Brue Catchment in the southwest of England. Validation results show a significant improvement in the estimation of global sunshine duration by the proposed method as compared to its predecessor (R 2 is improved from 0.68 to 0.83, root mean squared error (RMSE) from 2.37 h/d to 1.19 h/d and the mean biased error (MBE) from 0.21 h/d to 0.08 h/d). Further studies are needed to test this method in other parts of the world with different climate and geographical conditions.  相似文献   
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The virus, commonly known as COVID‐19 which emerged in Wuhan, China, in December 2019, has spread in 213 countries, areas or territories around the globe, with nearly 144 683 deaths worldwide on 18 April 2020. In the wake of this pandemic, we have witnessed a massive infodemic with the public being bombarded with vast quantities of information, much of which is not scientifically correct. Fighting fake news is now the new front in the COVID‐19 battle. This regular feature comments on the role of health sciences librarians and information professionals in combating the COVID‐19 infodemic. To support their work, it draws attention to the myth busters, fact‐checkers and credible sources relating to COVID‐19. It also documents the guides that libraries have put together to help the general public, students and faculty recognise fake news.  相似文献   
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Bread wheat varieties as influenced by different nitrogen levels   总被引:4,自引:2,他引:2  
INTRODUCTION Dera Ismail Khan lies in Pakistan’s arid zone (71.07° longitude, 31.57° latitude and 500 m above sea level). This zone is in the extreme south of (NWFP) Pakistan at the bank of the River Indus. Dera Ismail Khan is bounded by Sulaiman Range to the West, the Indus River on the East, Marwat and Bhit- tani Ranges on the North and Vehowa Nala (Punjab) on the South. Besides certain local variability the area is comprised of four basic divisions viz mountains, a series …  相似文献   
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Direct survey techniques deal with collecting information on sensitive issues data, such as induced abortion, drug addiction, and so on. RR (randomized response) techniques are available for many interviewees, who do not feel comfortable to disclose their personal data due to privacy risks. RR techniques are used in the estimation of the number of people having a sensitive attribute say A. When the research is conducted on the disgraceful or ignominious characteristics of persons like rash driving, tax elusion, induced abortion, testing HIV (human immunodeficiency virus) positive etc., RR techniques are used to make sure that the estimates obtained are efficient and unbiased. During these types of surveys, privacy of the respondent is also managed. Among others, the conflict between efficiency and protection of privacy was also discussed by Nayak in 1994. In RR-related techniques, the SRS (simple random sampling) is statistically used in the sample selection. In this paper, RR procedure is used that allows us to estimate the population proportion in addition to the probability of providing a truthful answer. This study also quantifies a method for the estimation of the model having one variable (univariate) while studying logistic regression, where the dependent variables are subject to RR. In addition, an efficiency comparison is carried out to investigate the performance of the proposed technique. It is also assumed that during the study, the respondents will respond keeping in view the instructions of the RR design. The general idea about findings of current study, though, is so as to perform RR techniques comparatively fine.  相似文献   
9.
Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects of pollutants from textile wastewater on the anatomy of the plant were studied. Water hyacinth exhibits hydrophytic adaptations which include reduced epidermis cells lacking cuticle in most cases, presence of large air spaces (7~50 μm), reduced vascular tissue and absorbing structures. Textile waste significantly affected the size of root cells.The presence of raphide crystals was noted in parenchyma cells of various organs in treated plants.  相似文献   
10.
This study examined the use of electronic resources among academic scholars of The Islamia University of Bahawalpur (IUB), Punjab, Pakistan. A quantitative survey was found most convenient and useful for this study. The total population of the study was 169 research students in IUB. The response rate was 79% and 133 utilizable responses were coded and analyzed by using SPSS software. Results of the study showed that most of the researchers (61%) used electronic resources daily for many purposes and reasons. Most of them (57%) were “satisfied” with the usage of electronic resources. Learning, education, and research were the main purposes, and easy use and easy access to documents were the major reasons of using these resources. Lack of internet connection is the major problem faced by the respondents.  相似文献   
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