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101.
102.
Climate change driven ocean acidification and hypercapnia may have a negative impact on fertilization in marine organisms because of the narcotic effect these stressors exert on sperm. In contrast, warmer, less viscous water may have a positive influence on sperm swimming speed and so ocean warming may enhance fertilization. To address questions on future vulnerabilities we examined the interactive effects of near-future ocean warming and ocean acidification/hypercapnia on fertilization in intertidal and shallow subtidal echinoids (Heliocidaris erythrogramma, H. tuberculata, Tripneustes gratilla, Centrostephanus rodgersii), an asteroid (Patiriella regularis) and an abalone (Haliotis coccoradiata). Batches of eggs from multiple females were fertilized by sperm from multiple males in all combinations of three temperature and three \textpH/P\textCO2 {\text{pH}}/P_{{{\text{CO}}_{2} }} treatments. Experiments were placed in the setting of projected near-future conditions for southeast Australia, an ocean change hot spot. There was no significant effect of warming and acidification on the percentage of fertilization. These results indicate that fertilization in these species is robust to temperature and \textpH/P\textCO2 {\text{pH}}/P_{{{\text{CO}}_{2} }} fluctuation. This may reflect adaptation to the marked fluctuation in temperature and pH that characterises their shallow water coastal habitats. Efforts to identify potential impacts of ocean change to the life histories of coastal marine invertebrates are best to focus on more vulnerable embryonic and larval stages because of their long time in the water column where seawater chemistry and temperature have a major impact on development.  相似文献   
103.
The aim of this study is to elucidate the osmoregulatory capabilities of the intertidal pulmonate Onchidium tumidium. Our results indicate that O. tumidium could tolerate hyperosmotic stress more effectively than hypoosmotic stress. In 10% seawater (SW), it was capable of maintaining its plasma hyperosmotic and hyperionic to the external medium. However, it rapidly gained weight in 10% SW, and no restoration of body weight was observed. In contrast, in 90% SW it was able to recover its body weight partially. In a hyperosmotic medium, accumulation of intracellular free amino acids (FAA) was responsible for cell volume regulation. The accumulated FAA might originate from protein catabolism, which occurred in the internal organs (IO). In contrast, the relatively smaller amination:deamination ratio of glutamate dehydrogenase in the body wall (BW) and IO of specimens exposed to hypoosmotic stress might lead to a higher rate of amino acid catabolism. This was supported by the greater ammonia contents in the BW and IO of, and higher rate of ammonia excretion by, specimens exposed to 10% SW. Received: 11 March 1998 / Accepted: 2 May 1999  相似文献   
104.
Environmental Chemistry Letters - Freshwater supply is declining in the context of climate change, pollution, and soil salinization, calling for sustainable methods to produce drinking water. For...  相似文献   
105.
Since the 1980s, green purchasing/green procurement has increasingly been recognised as an effective means of addressing and reducing negative environmental impacts related to product production and consumption around the world. This paper reviews the procurement practices and policies of five Asian countries and Hong Kong, in the context of an international overview of green purchasing and practices. The extent of government involvement in green procurement is found to directly determine its overall effectiveness, and up-to-date information resources clearly enhance delivery and performance. A case study in Hong Kong demonstrates how public leadership on green procurement has advanced green procurement in the private sector.  相似文献   
106.
To investigate the environmental behavior of volatile organic compounds (VOCs) in urban areas, their concentrations were measured at four urban monitoring sites (namely, N, S, E, and W) in Seoul, Korea (February to December 2009). A total of 27 compounds were quantified that consist of four chemical groups: aromatic (AR), halogenated aromatic, halogenated paraffin, and halogenated olefin. Results were evaluated by focusing on these four functional groups just mentioned and their summation term as total VOC (TVOC) along with several individual species (mainly AR species, that is, benzene, toluene, ethylbenzene, and xylene). The highest concentration of chemical groups was found from AR (71.1±42.1?ppbC), while that for individual species confirmed the dominance of toluene (7.48±3.88?ppb). The analysis of spatial distribution indicated that high TVOC levels were recorded at sites N and W, while it was not so significant such as S and E in terms of TVOC budget. Seasonal variation of these VOCs was characterized by the peak values in December to reflect the combined effects of pronounced source activities and meteorological conditions. Analysis of spatial variations in VOC levels between the four urban sites indicated that their distributions are tightly affected by local source processes in each area.  相似文献   
107.
No studies were reported on the field of coastal eutrophication research by using bibliometrics. The objective of this study was to evaluate the coastal eutrophication research performance based on all the related articles in Science Citation Index databases from 1993 to 2008. Document type, publication output, authorship, keywords, publication pattern, country, and institute of publication were analyzed. The USA contributed 35.0% of total articles where the ten major industrial countries accounted for the majority of the total production. An indicator citation per publication was presented in this study to evaluate the impact of number of authors, institutes, countries, and journals. The mean value of citation per publication of collaborative papers was higher than that of single country or institute publications. Collaboration trend was toward multi-authors, multi-institutes and multi-countries papers. This was coincident with the research trends of coastal eutrophication, which was thought to be a component of global change. Additionally, keywords analysis was used to indicate the formation and shift of hot research.  相似文献   
108.
Chen Y  Lu A  Li Y  Yip HY  An T  Li G  Jin P  Wong PK 《Chemosphere》2011,84(9):1276-1281
The photocatalytic disinfection of Escherichia coli K-12 is investigated by the natural sphalerite (NS) under different spectra, wavelengths and intensities of visible light (VL) emitted by light-emitting-diode lamp (LED). The spectrum effect of VL on disinfection efficiency is studied by using white LED, fluorescent tube (FT) and xenon lamp (XE), which indicates that the “discreted peak spectrum” of FT is more effective to inactivate bacteria than “continuous spectrum” of LED and XE. Besides, the photocatalytic disinfection of bacteria is compared under different single spectrum (blue, green, yellow and red color) LEDs. The results show that the most effective wavelength ranges of VL for photocatalytic disinfection with the NS are 440-490 and 570-620 nm. Furthermore, a positive relationship is obtained between the disinfection efficiency and the VL intensity. The experiment shows that NS can completely inactivate 107 cfu mL−1E. coli K-12 within 8 h irradiation by white LED with the intensity of 200 mW cm−2 at pH 8. Moreover, the destruction process of the cell wall and the cell membrane are directly observed by TEM. Finally, no bacterial colony can be detected within a 96 h regrowth test of inactivated bacteria, which reveals that the VL-photocatalytic disinfection leads to an irreversible damage to the bacterial cells.  相似文献   
109.
In recent times, the quality of medical care has been continuously improving in medical institutions wherein patient-centred care has been emphasized. Failure mode and effects analysis (FMEA) has also been promoted as a method of basic risk management and as part of total quality management (TQM) for improving the quality of medical care and preventing mistakes. Therefore, a study was conducted using FMEA to evaluate the potential risk causes in the process of infectious medical waste disposal, devise standard procedures concerning the waste, and propose feasible plans for facilitating the detection of exceptional cases of infectious waste. The analysis revealed the following results regarding medical institutions: (a) FMEA can be used to identify the risk factors of infectious waste disposal. (b) During the infectious waste disposal process, six items were scored over 100 in the assessment of uncontrolled risks: erroneous discarding of infectious waste by patients and their families, erroneous discarding by nursing staff, erroneous discarding by medical staff, cleaning drivers pierced by sharp articles, cleaning staff pierced by sharp articles, and unmarked output units. Therefore, the study concluded that it was necessary to (1) provide education and training about waste classification to the medical staff, patients and their families, nursing staff, and cleaning staff; (2) clarify the signs of caution; and (3) evaluate the failure mode and strengthen the effects.  相似文献   
110.

Purpose

We used a sequential extraction to investigate the effects of compost amendment on Cd fractionation in soil during different incubation periods in order to assess Cd stabilization in soil over time.

Methods

Pot experiments using rice plants growing on Cd-spiked soils were carried out to evaluate the influence of compost amendment on plant growth and Cd accumulation by rice. Two agricultural soils (Pinchen and Lukang) of Taiwan were used for the experiments. The relationship between the redistribution of Cd fractions and the reduction of plant Cd concentration due to compost amendment was then investigated.

Results and discussion

Compost amendment in Pinchen soil (lower pH) could transform exchangeable Cd into the Fe- and Mn-oxide-bound forms. With increasing incubation time, exchangeable Cd tended to transform into carbonate- and Fe- and Mn-oxide-bound fractions. In Lukang soil (higher pH), carbonate- and Fe- and Mn-oxide-bonded Cd were the main fractions. Exchangeable Cd was low. Compost amendment transformed the carbonate-bound form into the Fe and Mn oxide form. Pot experiments of rice plants showed that compost amendment enhanced plant growth more in Pinchen soil than in Lukang soil. Compost amendment could significantly reduce Cd accumulation in rice roots in both Pinchen and Lukang soils and restrict internal transport of Cd from the roots to the shoots. Because exchangeable Cd can be transformed into the stronger bonded fractions quickly in Pinchen soil, a reduction of Cd accumulation in rice due to compost amendment of Pinchen soil was significant by 45?days of growth. However, carbonate-bonded fractions in Lukang soil may provide a source of available Cd to rice plants, and exchangeable and carbonate-bonded fractions are transformed into the other fractions slowly. Thus, reduction of Cd accumulation by rice due to compost amendment in Lukang soil was significant by 75?days of growth.

Conclusions

The results of the study suggest that the effectiveness of compost amendment used for stabilization of Cd and to decrease the phytoavailability of Cd for rice plants is different in acidic and alkaline soils. In acidic soil, Cd fractionation redistributes quickly after compost amendment and shows a significant reduction of Cd accumulation by the plant within a few weeks. In alkaline soil, due to the strongly bound fractions of Cd being in greater quantity than the weakly bound ones, a longer period (a few months) to redistribute Cd fractions is needed.  相似文献   
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