Evaluation of bio-aerosols type,density, and modeling of dispersion in inside and outside of different wards of educational hospital

Environmental Science and Pollution Research - Exposure to bioaerosols in the air of hospitals is associated with a wide range of adverse health effects due to the presence of airborne...     

Enhanced phytoremediation: A study of mycorrhizoremediation of heavy metal–contaminated soil

Arbuscular mycorrhizal fungi (AMF) are microscopic fungi that occur naturally in soil and form a symbiosis with plant roots. By colonizing the roots, the fungus increases plant growth by making soil essential elements like zinc and phosphorus more accessible. AMF can play a role in the phytoremediation of heavy metal–contaminated soil (mycorrhizoremediation). Two research experiments were conducted to evaluate the impact of AMF on the extraction of different heavy metals (arsenic, cadmium, lead, selenium, and zinc) in contaminated soil. A grass mixture composed of Festuca rubra, Festuca eliator, Agropyron repens, and Trifolium repens was used in the experiments, and four different types of AMF were investigated: Glomus intraradices, Glomus mosseae, Glomus etunicatum, and Gigaspora gigantea. The results of the study showed that heavy metal extraction by Glomus intraradices colonized plants was the highest of all four AMF tested and was generally higher than nonmycorrhizal plants, depending on the heavy metal concentration in soil and whether it interacted with other metals in soil. However, metal extraction by AMF colonized grasses reached a plateau after an approximately two‐month period showing no further phytoaccumulation. © 2006 Wiley Periodicals, Inc.     

探究式教学模式下物理实验的设计与实现

随着新的教育、教学技术的不断涌现和新的教学模式的提出,传统的实验教学模式已经不能满足现代素质教育的要求,急需新的更为先进的教学模式来提高实验教学的效果。在此背景下,笔者通过研究探究式教学模式,并将此模式应用到大学物理实验教学中,取得了良好的效果。     

The diagnostic performance of cytogenetic investigation in amniotic fluid cells and chorionic villi

First-trimester chorionic villus sampling has not reached the popularity of second-trimester amniocentesis in prenatal cytogenetic diagnosis, in contrast to initial expectations. We investigated whether a difference inthe diagnostic performances of cytogenetic investigation in amniotic fluid (AF) cells and chorionic villi in favour of AF-cells might justify this. Diagnostic performance was measured as laboratory failure rate, karyotype quality (G-band score, rate of follow-up samples, rate of wrong diagnoses), and karyotype representativity (rate of follow-up samples, rate of wrong diagnoses). From 1993–1999, 11 883 AF-samples were investigated (AF-cells). In chorionic villi, short term culture preparations solely were karyotyped from 1993–1996 (n=3499) (STC-villi), short and long-term culture preparations simultaneously provided a sufficient amount of tissue being available from 1997 onwards (n=1829) ((STC+LTC)-villi). Laboratory failure rates were the same after amniocentesis (0.40%) and chorionic villus sampling (0.50%). G-band scores (mean±SD) were equal in AF-cells (373±38.1) and LTC-villi (364±32.6) but significantly lower in STC-villi (311±34.6) (p=0.001). Follow-up sampling rates because of quality reasons were the same in AF-cells (0.14%), STC- villi (0.13%) and (STC+LTC)-villi (0.11%). Two wrong diagnoses turned up among AF-cells. Follow-up sampling rates because of representativity reasons differed significantly between AF-cells (0.10%), (STC+LTC)-villi (1.31%), and STC-villi (1.99%) (p<0.001). However, the ratios of the total numbers of follow-up samples and uncertain or abnormal cytogenetic results in STC, and (STC+LTC)-villi at cytogenetic risks ⩾3% (0.132 and 0.160, respectively) were equal to that in AF-cells at risks <3% (0.155). Two wrong diagnoses were made in STC-villi. Diagnostic performance improved in the rank order of STC-villi, (STC+LTC)-villi and AF-cells. At cytogenetic risks ⩾3%, (STC+LTC)-villi showed a diagnostic performance equal to that in AF-cells. This might justify a selective use of chorionic villus sampling. Copyright © 2001 John Wiley & Sons, Ltd.     

Removal of Selected Urban Stormwater Constituents by an On-stream Pond

A methodologyis presented for assessing the pollution control performance of an on-stream stormwater pond, and the application of this methodology to a specific facility in Kingston, Ontario, Canada is documented. This assessment is based on constituent mass balances for both baseflow and event conditions. Results on removal rates are provided for selected dissolved constituents, nutrients, suspended solids, metals and organic contaminants. In summary, dissolved constituents exhibit zero removal for baseflow periods and positive removal for events; nutrients and suspended solids exhibit negative removal for baseflow periods and positive removal for events; and metals and organics exhibit positive removal for both baseflow periods and events. Constituent removal appears to be controlled mainly by physical processes (sedimentation), and the uncertainties associated with the estimates of constituent loads are quantified.     

Current controversies in prenatal diagnosis 1: NIPT for chromosome abnormalities should be offered to women with low a priori risk

In its successful annual cycle of controversies and debates, the International Society of Prenatal Diagnosis and Therapy once again addressed non-invasive prenatal testing (NIPT) by following up on the 2013 controversy, ‘Should non-invasive DNA testing be the standard screening test for Down syndrome in all pregnant women’? with the proposition, ‘NIPT for chromosomel abnormalities should be offered to women with low a priori risk’. © 2014 John Wiley & Sons, Ltd.     

清洁生产观点1:生产与工业发展

对清洁生产的定义仍然合适吗?促进清洁生产的潜在的关键性假设在今天的工业世界依然行得通吗?如何改变清洁生产计划以提高其效率并在未来十年在对它的理解方面产生飞跃?这篇文章就谈论了这类问题.并在改进目前的清洁生产实践方面提出了建议.