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581.
Maria Sabeen Abdol Ghaffar Ebadi Zulfiqar Ahmad Bhatti Faridullah Muhammad Irshad 《毒物与环境化学》2019,101(7-8)
Statement of RetractionWe, the Editors and Publisher of Toxicological & Environmental Chemistry, have retracted the following article:Maria Sabeen, Qaisar Mahmood, Abdol Ghaffar Ebadi, Zulfiqar Ahmad Bhatti, Faridullah, Muhammad Irshad, Allauddin Kakar, Muhammad Bilal, Hafiz Muhammad Arshad and Naeem Shahid, ‘Consequences of health risk assessment of wastewater irrigation in Pakistan Israel Affairs’, Toxicological & Environmental Chemistry, 2019, DOI: 10.1080/02772248.2019.1619335The article is retracted due to the oversights that were made during peer review process that resulted in the article being published online in error. Further review from independent reviewers was sought. This confirmed that the central findings and methodology of the study in question are unreliable and therefore unsuitable for publication.We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions.The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”. 相似文献
582.
The literature on routinization of work is both ambiguous and equivocal when its impact on quality of working life is considered. The classical management literature suggests that routinization of work has a positive influence on individual performance and by implication on the quality of working life resulting from the overall prosperity generated. However, more recent literature on job characteristics and job design argues that routinization of work has a negative impact on individual performance as it suppresses creative expression on the job. This paper suggests that these mixed findings are due to an inadequate theoretical grasp of the concept of routinization and presents empirical evidence which attempts to clarify the ambiguity. Data were collected from 1148 nurses working in anglophone hospitals in the greater Montreal area in the form of a field survey questionnaire. The results indicated that nurses who worked routine shifts perceived higher levels of quality of working life compared to those on non-routine shifts. The results also indicated that nurses who experienced high routinization in job content perceived lower levels of quality of working life compared to those nurses who experienced low routinization in job content. Implications of these findings for future research are discussed. 相似文献
583.
The present study examined the relationship of shiftwork and department-type with employees' job stress, stressors, work attitudes and behavioral intention. Data were collected by means of a structured questionnaire from nurses (N = 1148) working in eight hospitals in a large, metropolitan city in eastern Canada. One-way ANOVA, MANOVA and two-way ANOVA were used to analyze data. Results generally support the prediction that nurses working on fixed shifts were better off than nurses working on rotating shifts in terms of the dependent variables of the present study. The prediction that nurses working in non-intensive care departments were better off than nurses working in intensive care departments received mixed support at best. A few interaction effects of shiftwork × department-type on dependent variables were also noted. The impact of socio-demographic variables — age, marital status, cultural background (English- versus French-speaking) — on the above relationships were also analyzed. Results are discussed in light of the previous empirical evidence on shiftwork and department-type. 相似文献
584.
Muhammad Akram Kahlown Joel R. Hamilton 《Journal of the American Water Resources Association》1994,30(1):125-134
ABSTRACT: The karez is a traditional irrigation water source, consisting of hand-dug horizontal wells, that is still used in parts of South Asia, the Middle East, and North Africa. This paper describes the construction, management, and current problems of karez irrigation systems based on investigations conducted in Baluchistan Province, Pakistan. While karezes have served irrigation needs well in the past, they are now threatened by high costs of labor for construction and maintenance, and by the encroachment of tubewells which lower the water tables on which the karez systems depend. Possible methods for improving karez performance and needs for research are discussed. 相似文献
585.
Muhammad Aslam Chaudhry Robert A. Young 《Journal of the American Water Resources Association》1989,25(5):1055-1061
ABSTRACT: Linear programming models of a representative farm in a district of Pakistan's Punjab Province are formulated for the purpose of estimating the value of irrigation water. The models provide for choices among several irrigation levels for each potential crop. Solutions of the model for several water supply situations provide the basis for approximating the total, average, and marginal values of irrigation water. Prices for important crops in Pakistan are controlled at levels below their levels elsewhere in the world, so models are specified for both financial (domestic price) and economic (world price) scenarios. The value of water to society (its economic value) is high relative to the costs of some generally available water-augmenting investments, while financial values, which measure water management and allocation incentives faced by farmers, are less than the corresponding economic values. At current water supply levels, incremental returns to added water estimated from the economic model would justify investments in water-saving or water-augmenting technologies, while such a decision would be barely attractive assuming financial prices. While present government commodity price policies may serve to protect low-income and non-farm members of the population, they also inhibit farmer investments to increase the productivity of scarce irrigation water. 相似文献
586.
Azhar Abbas Muhammad Ajaz Hussain Muhammad Amin Muhammad Sher Muhammad Nawaz Tahir Wolfgang Tremel 《环境科学学报(英文版)》2015,37(11):51-58
Chemically modified pullulan was evaluated for its sorption efficiency and selectivity to remove cadmium(Cd) from spiked high-hardness groundwater(GW). Pullulan esterified with succinic anhydride using dimethylaminopyridine showed a fairly high degree of substitution value as confirmed by1 H NMR spectroscopy. Pullulan succinate(Pull-Suc) was converted into the sodium salt(Pull-Suc-Na). The effect of contact time(5–200 min) and p H(2–8) on Cd-uptake by the sorbent(Pull-Suc-Na) was investigated. The sorbent showed more than 90% Cd-removal in first 15 min from distilled water(DW) and GW solution,respectively. Comparison of Pull-Suc-Na with other polysaccharidal sorbents suggested its high efficiency(DW 476.2 mg/g and GW 454.5 mg/g) and selectivity for the removal of Cd by an ion exchange mechanism, which is further supported by the negative Gibbs free energy values calculated from Langmuir isotherms. A Langmuir isotherm kinetic model provided the best fit for the sorption of Cd using Pull-Suc-Na. The sorbent showed a negligible decrease in Cd-uptake over three regeneration cycles. The thermal stability testing of the sorbents indicated that Pull-Suc-Na(sorbent) is more stable than Pull-Suc. 相似文献
587.
Qaisar Mahmood Arshid Pervez Syeda Shaima Meryem Muhammad Waseem Zahid Ullah 《毒物与环境化学》2015,97(5):634-639
The aim of this study was designed to determine the influence of welding fumes on oxidative stress in humans and the role of metals. A questionnaire was designed to collect information regarding personal characteristics, including age, weight, height, and medical history; life style such as smoking status and exercise habits; and occupational history such as working history, working environment, employment duration, and use of protective equipment. Body mass index (BMI) in kg/m2 was then calculated for each participant. Blood samples were also drawn to determine malondialdehyde (MDA) levels and various metals in plasma. Significantly higher plasma MDA (4.08 µg/L) was observed as compared to controls (1.61 µg/L). Blood metal analysis also showed elevated level of metals in welders for cadmium, chromium, lead,and nickel. Data indicated that workers occupationally exposed to welding fumes for prolong periods possessed higher metal levels associated with increased oxidative stress as evidenced by elevated MDA levels. 相似文献
588.
Sludge granulation and e ciency of phase separator in UASB reactor treating
combined industrial e uent 总被引:1,自引:0,他引:1
Abdullah Yasar Nasir Ahm Muhammad Nawaz Chaudhry Aamir Amanat Ali Khan 《环境科学学报(英文版)》2007,19(5):553-558
Sludge granulation and the effect of gas-liquid-solid separator (GLSS) design on the efficiency of upflow anaerobic sludge blanket (UASB) and upflow anaerobic sludge filter (UASF) reactors, operating at HRTs ranging from 3 to 12 h was investigated. VSS/TS ratio gradually increased in both the reactors with increasing sludge age (from 0.5 to more than 0.7 for UASB reactor and 0.012 to 0.043 for UASF reactor). X-Ray diffraction analysis of the UASF sludge showed the presence of expanding clays revealing its additional absorption capability. Fuoraphyllite and albite precipitation related to excellular polymers of the microbial shell structure, showed the extended growth of microorganisms during sludge granulation. A gradual decrease (82%-69%) in COD removal with decreasing HRT was apparent in UASF reactor. In case of UASB reactor, this decrease was marginal because addition of GLSS device significantly improved (14%-20%) the overall efficiency of the UASB reactor. GLSS enhanced the efficiency of the UASB reactor by increasing the settleability of suspended particles and accelerating the coagulation of colloidal particles due to the velocity gradient. 相似文献
589.
Pesticides exposure in Pakistan: a review 总被引:2,自引:0,他引:2
This is the first systematic review of studies done since 1960, and to give an integrated picture of pesticides exposure to humans, animals, plants, waters, soils/sediments, atmosphere etc. in Pakistan. Authors have extracted data from different departments, published literature in research journals and National reports. Although the wide-spread usage of pesticides in Pakistan has controlled the pests, but like other countries, it has started causing environmental problems in the area. In some areas of Punjab and Sindh groundwater has been found contaminated and is constantly being under the process of contamination due to pesticide use. There is considerable evidence that farmers have overused and misused pesticides especially in cotton-growing areas. It is evident from the biological monitoring studies that farmers are at higher risk for acute and chronic health effects associated with pesticides due to occupational exposure. Furthermore, the intensive use of pesticides (higher sprays more than the recommended dose) in cotton areas involves a special risk for the field workers, pickers, and of an unacceptable residue concentration in cottonseed oil and cakes. The authors have also discussed the merits and demerits of different studies. The review will set the future course of action of different studies on pesticide exposure in Pakistan. Data limitations are still the major obstacle towards establishing clear environmental trends in Pakistan. The authors suggest that a reliable monitoring, assessment and reporting procedures shall be implemented in accordance with appropriate environmental policies, laws and regulations in order to minimize the pesticides exposure. 相似文献
590.