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341.
Heterotopic pregnancy occurs rarely following natural conception; however, intrauterine embryo transfer following in vitro fertilization is a known risk factor for its occurrence. A 29-year-old woman presented with acute abdomen at 14w5d gestation following in vitro fertilization–embryo treatment. A ruptured heterotopic gestation in the left fallopian tube was identified at laparoscopy and treated by salpingectomy. Subsequently, at 21-week gestation, routine sonogram demonstrated bilateral ventriculomegaly in the intrauterine fetus. Fetal magnetic resonance imaging was highly suggestive of ischemic brain injury, most likely attributable to the maternal hypovolemic shock because of ruptured heterotopic gestation. The pregnancy was terminated by intracardiac injection and induction of labor. Timely diagnosis of heterotopic pregnancy requires a high index of suspicion as diagnostic delays can have catastrophic consequences for the mother and/or the intrauterine fetus. © 2015 John Wiley & Sons, Ltd. 相似文献
342.
Mohammad Hossein Keshavarz Somayeh Moradi Ali Reza Madram Hamid Reza Pouretedal Karim Esmailpour Arash Shokrolahi 《Journal of Loss Prevention in the Process Industries》2013,26(4):650-659
This work presents a novel, reliable and simple method of estimating the flash point of various types of flammable amines, which are important for safety measures in industrial processes. Different amines include aliphatic amines such as primary, secondary, tertiary and cyclic amines as well as aromatic amines and hetero arenes containing nitrogen heteroatom. The proposed correlation is based on the contribution of some specific molecular moieties and functional groups, which can easily be used for any types of amines. Intermolecular forces are important in the new method, which are counted by two increasing and decreasing parameters. The root mean square (rms) deviation is 18 K for different classes of amines including 133 diverse compounds. The estimated flash points have been compared with one of the best available predictive methods, which gives much lower value of the rms deviation. 相似文献
343.
Mehrzad Kherad Hossein Ahani Mohammad Reza Kousari Arman Beyraghdar Kashkooli Mohammad Amin Karampour 《Environment, Development and Sustainability》2013,15(4):1129-1142
Fars Comprehensive Agricultural Database was created to remove bottlenecks and constrains of province for decision makers in a way that leads to sustainable agriculture. Regarding Fars agricultural comprehensive information database, and the importance of wheat as the strategic commodity, this study was conducted in Ali-Abad-e-Kamin (Pasargad, Iran) to assess two most important managerial factors affecting other agricultural factors. Therefore, in this study, besides evaluating the effect of water resource on wheat yield and other traits, education impacts were analyzed and evaluated as well. Data were collected regarding cadastre land use information derived from satellite imagery combined with GIS potencies, and also a comprehensive questionnaire was completed to collect local field information. Results revealed that educational level has significant effect on crop yield, fields’ area and seed consumption rate and also effect of water resource showed significant difference for crop yield, fields’ area. Finally, interactive effect of water resource and educational level showed significant difference just for wheat yield. Also, as a result, higher education positively results in improved wheat yield, lands’ area and seed consumption rate. On the other hand, river as a type of sustainable water resource with karstic geological formations positively affected wheat yield, lands’ area and farms distance from village. Overall, transferring knowledge from relevant organization resulting in higher productivity seems to be necessary. 相似文献
344.
Hossein Faghihian Mozhgan Iravani Mohammad Moayed Mohammad Ghannadi-Maragheh 《Environmental Chemistry Letters》2013,11(3):277-282
Radioactive wastes containing Cs+ and Sr2+ are among the most dangerous environmental pollutants. Therefore, removing Cs+ and Sr2+ from environmental media is needed. Removal can be done by nanocrystalline ion exchangers. Nanocrystalline ion exchangers are studied in depth for the treatment of nuclear wastes because these exchangers have high exchange capacity and fast kinetics. However, operating the columns of these exchangers is very difficult. This issue may be overcome by the preparation and use of nanocomposites. Here, we prepared a novel polyacrylonitrile–zeolite nanocomposite for the removal of Cs+ and Sr2+ in a fixed-bed column operation. We studied the effect of influent flow rate, nanocomposite bed height and initial concentrations. Experimental data were analysed using the Thomas model and the bed-depth service time model. The results reveal that total adsorbed ion and bed capacity increased with increasing initial ions concentration and bed height; and decreased with increasing influent flow rate. The maximum bed capacity was 0.085 meq/g for Cs+ and 0.128 meq/g for Sr2+. The critical bed height (Z 0) was 4.35 cm for Cs+ and 2.89 cm for Sr2+. These findings demonstrate that the new nanocomposite is suitable for removal of Cs+ and Sr2+. 相似文献
345.
Mohammad S. Farhadinia Paul J. Johnson Alexandra Zimmermann Philip J.K. McGowan Erik Meijaard Mark Stanley-Price David W. Macdonald 《Conservation biology》2020,34(4):988-996
The persistence of endangered species may depend on the fate of a very small number of individual animals. In situ conservation alone may sometimes be insufficient. In these instances, the International Union for Conservation of Nature provides guidelines for ex situ conservation and the Convention on Biological Diversity (CBD) indicates how ex situ management can support the CBD's objectives by providing insurance policies for species. The circumstances that justify its use are uncertain. To evaluate the current in situ extinction risk and ex situ management of 43 critically endangered species of mammalian megafauna, we used nonmetric multidimensional scaling and geopolitical variables related to governance, economics, and national policy within their extant ranges. We then fitted generalized additive models to assess the contribution of each variable to the ordination. Fifteen (almost one-third) of the world's terrestrial mammalian megafauna are not the subject of any ex situ management. Seventy-three percent of these taxa occur in areas characterized by political uncertainty, such as border zones or areas affected by armed conflicts, mainly in Africa and the Middle East. A further 23% of taxa in ex situ programs do not meet sustainability criteria for inbreeding avoidance. Strategic conservation planning, such as the One Plan approach, may improve ex situ management for these taxa. Given the escalating trend in threats afflicting megafauna, ex situ management should be considered more rigorously, particularly in politically unstable regions, to achieve CBD Target 12 (prevent extinction of threatened species). 相似文献
346.
Ahmadi Zahed Moradabadi Alireza Abdollahdokht Danial Mehrabani Mehrnaz Nematollahi Mohammad Hadi 《Environmental science and pollution research international》2019,26(20):20411-20417
Environmental Science and Pollution Research - Gasoline station attendants spend a great deal of their time in the direct exposure to noxious substances such as benzene and byproducts of gasoline... 相似文献
347.
348.
Mosammat Zamilun Nahar Mohammad Salim Zahangir S.M.Shafiqul Islam 《中国人口.资源与环境(英文版)》2013,11(3):227-235
The 2007 Bangladesh Demographic and Health Survey(BDHS)data are exploited to examine the effects of socioeconomic and demographic factors on age at first marriage linkage to reproductive behavior of Bangladeshi women.The mean age at first marriage of women is found to be 15.48 years.Multivariate logistic regression technique shows that place of residence,religion,region,wealth index,education,and occupation are significantly important factors for determining age at first marriage.The relationship between marriage and fertility suggests that women who marry at a younger age produce more children than women who marry late.Findings of this study show that if the age at first marriage of adolescents is increased by 1 year,the age at first birth is postponed by 0.728 years.With the increase in age at first marriage,the fecundability of women sharply rises,whereas the proportion of temporary sterility decreases.Although there is a positive association between age at first marriage and age-specific marital fertility rates,the total parity per woman at the end of the reproductive period is expected to reduce by 0.196 for each 1-year delayed marriage. 相似文献
349.
Ta Yeong Wu Abdul Wahab Mohammad Jamaliah Md. Jahim Nurina Anuar 《Journal of environmental management》2010,91(7):1467-1490
Palm oil production is one of the major industries in Malaysia and this country ranks one of the largest productions in the world. In Malaysia, the total production of crude palm oil in 2008 was 17,734,441 tonnes. However, the production of this amount of crude palm oil results in even larger amounts of palm oil mill effluent (POME). In the year 2008 alone, at least 44 million tonnes of POME was generated in Malaysia. Currently, the ponding system is the most common treatment method for POME but other processes such as aerobic and anaerobic digestion, physicochemical treatment and membrane filtration may also provide the palm oil industries with possible insights into the improvement of POME treatment processes. Generally, open ponding offers low capital and operating costs but this conventional method is becoming less attractive because the methane produced is wasted to the atmosphere and the system can not be certified for Carbon Emission Reduction trading. On the other hand, anaerobic digestion of POME provides the fastest payback of investment because the treatment enables biogas recovery for heat generation and treated effluent for land application. Lastly, it is proposed herewith that wastewater management based on the promotion of cleaner production and environmentally sound biotechnologies should be prioritized and included as a part of the POME management in Malaysia for attaining sustainable development. This paper thus discusses and compares state-of-the-art POME treatment methods as well as their individual performances. 相似文献
350.
Design of River Water Quality Monitoring Networks: A Case Study 总被引:3,自引:0,他引:3
Mohammad Karamouz Reza Kerachian Masih Akhbari Bahareh Hafez 《Environmental Modeling and Assessment》2009,14(6):705-714
Karoon River, from Gotvand Dam to Persian Gulf with more than 450 km in length and an annual discharge of 11,891 million cubic
meters, is the largest river in Iran. Increasing water withdrawal from and wastewater discharge to the river has endangered
the aquatic life of this important ecosystem. Furthermore, the drinking and in-stream water quality standards have been violated
in many instances. In this paper, a river water quality monitoring network is designed, including determination of sampling
frequencies as well as location of water quality monitoring stations. In this regard, two models are developed. The first
model is a Genetic Algorithm-based optimization model and the second one is a combination of Kriging method and Analytical
Hierarchy Process. The temporal variation of the concentration of water quality variables along Karoon and Dez Rivers are
evaluated and the main water quality indicators are selected. Then, thirty five stations are selected and the application
of Entropy Theory in calculating the sampling frequency is demonstrated. The results show the significant value of the proposed
methodology in the design of monitoring network. 相似文献