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101.
Environmental Science and Pollution Research - Emissions from vessels are a major environmental concern because of their impacts on the deterioration of the environment, especially global warming...  相似文献   
102.
ABSTRACT

A method was developed to reproducibly measure environmental tobacco smoke (ETS) components generated by different cigarettes. Measurements were carried out in an unventilated, controlled environment chamber. True ETS (the aged and diluted combination of exhaled mainstream plus sidestream smoke) was generated by human smokers. To reliably quantitate components normally present at trace levels, the comparisons were carried out at elevated ETS concentrations—greater than 40 times those typically encountered in “real-world” settings.

The method was applied to four commercially available cigarettes and a cigarette prototype that primarily heats tobacco. Forty-three properties and components of the gas and particulate phases of ETS generated by the different cigarettes were measured. Good precision of measurement was obtained both within and between tests. Statistically significant differences in the concentration of ETS components were observed among the different commercial cigarettes and between the commercial and prototype cigarettes. Most ETS components from the prototype cigarette were reduced by >90% when compared to the commercial cigarettes. The method was used to determine the effect of cigarette design changes on the generation of ETS.  相似文献   
103.
Municipal services in the Palestinian Authority (PA) areas, including the West Bank and Gaza Strip (WBGS), are facing serious difficulties that have been intensified following the outbreak of the Palestinian uprising in late September 2000. The solid waste management services, being the most essential services provided by the municipalities and village councils, are mostly affected by the ongoing harsh situation and hence proper solutions that take into account the actual amount of generated municipal solid waste and its composition is a pre-requisite for planning proper treatment. Hence, a study was carried out to identify the actual status of solid waste in eight West Bank districts. A social survey was also conducted to collect information concerning the level of public awareness among communities surveyed to the perception of solid waste recycling and reuse. The results of the survey conducted in 2001–2002 were later reviewed during July–October 2008 to assess if the trend of domestic solid waste generation had changed. Based on the survey and post-assessment, it is found that political and economic conditions have both significantly impacted the trend of generated municipal solid waste and since no improvements in either condition are forthcoming, it is concluded that survey results could be used in a planning study. A possible handling of the generated wastes may entail transferring the recyclable waste to Israeli recycling industries, and in constructing three composting plants in different accessible locations in the West Bank.  相似文献   
104.
105.
The main aim of this systematic review was to explore the outcome of fetuses with isolated echogenic bowel (EB) on antenatal ultrasound. Inclusion criteria were singleton pregnancies with isolated EB no associated major structural anomalies at the time of diagnosis. The outcomes observed were: chromosomal anomalies, cystic fibrosis (CF), associated structural anomalies detected only at follow-up scans and at birth, regression during pregnancy, congenital infections, intra-uterine (IUD), neonatal (NND) and perinatal (PND) death. Twenty-five studies (12 971 fetuses) were included. Chromosomal anomalies occurred in 3.3% of the fetuses, mainly Trisomy 21 and aneuploidies involving the sex chromosomes. Cystic fibrosis occurred in 2.2%. Congenital infections affected 2.2%, mainly congenital Cytomegalovirus (CMV) infection. The majority of fetuses with EB experienced regression or disappearance of the EB at follow-up scans. Associated anomalies were detected at a follow-up scan in 1.8%. Associated anomalies were detected at birth and missed at ultrasound in 2.1% of cases. IUD occurred in 3.2% of cases while the corresponding figures for NND and PND were 0.4% and 3.1%. Fetuses with EB are at increased risk of adverse perinatal outcome, highlighting the need for a thorough antenatal management and postnatal follow-up. Assessment during pregnancy and after birth should be performed in order to look for signs of fetal aneuploidy, congenital infections and associated structural anomalies.  相似文献   
106.
107.
Lake Edku is one of the Nile Delta shallow brackish water coastal lagoons with communications with the southeastern Mediterranean.

Sediment samples were recovered from the top 10 cm of the lake bottom to study principally their total, inorganic and organic phosphorus. Related sediment parameters such as particle size, organic carbon, carbonate and iron contents were also studied in detail.

It is shown that the lake sediments are generally a sand-silt-clay mud enriched with carbonate (11.4-42%), organic carbon (0.9-11.4%) and iron (1.6-5.6%).

The total phosphorus content in these sediments is 503-1329 μg/g, inorganic phosphorus, 468-954 μg/g and organic phosphorus, 35-526 μg/g.  相似文献   
108.
Prenatal gene therapy aims to deliver genes to cells and tissues early in prenatal life, allowing correction of a genetic defect, before long-term tissue damage has occurred. In contrast to postnatal gene therapy, prenatal application can target genes to a large population of dividing stem cells, and the smaller fetal size allows a higher vector-to-target cell ratio to be achieved. Early-gestation delivery may allow the development of immune tolerance to the transgenic protein which would facilitate postnatal repeat vector administration if needed. Targeting particular organs will depend on manipulating the vector to achieve selective tropism and on choosing the most appropriate gestational age and injection method for fetal delivery. Intra-amniotic injection reaches the skin, and other organs that are bathed in the fluid however since gene transfer to the lung and gut is usually poor more direct injection methods will be needed. Delivery to the liver and blood can be achieved by systemic delivery via the umbilical vein or peritoneal cavity. Gene transfer to the central nervous system in the fetus is difficult but newer vectors are available that transduce neuronal tissue even after systemic delivery. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
109.
Agricultural wastes, oil palm trunk (OPT) veneer and oil palm empty fruit bunch (EFB) mat were used for the preparation of hybridized plywood using 250 and 450 g/m2 of urea formaldehyde (UF) as gluing agent. The mechanical (flexural strength, flexural modulus, screw withdrawal, shear strength), physical (density, water absorption, thickness swelling and delamination) and thermal (TGA) properties of the biocomposites were studied. Images taken with a scanning electron micrograph (SEM) indicated an improvement in the fiber–matrix bonding for the laminated panel glued with 450 g/m2 of UF.  相似文献   
110.
Abstract: Water industry experts have been arguing that the traditional techniques are not an accurate means of measuring water contamination. This is mainly because these techniques emphasize neither the stochastic nature of the water contamination process nor the precision and the accuracy of the tested methods used by environmental laboratories. In this work, we describe the development and application of prototype Dynamic Bayesian Networks (DBNs) that model ground‐water quality to determine the impact of chemical contaminants on ground‐water quality in the Salalah area, which is allocated to the south of Oman. We also present a new technique for data pre‐processing because it is needed for the treatment of ground‐water datasets that are used as the data source to learn the probabilities for dynamic decision models. Among more than 20 wells in area, only four wells were selected to be analyzed and the results show that we achieved an acceptable level of efficiency.  相似文献   
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