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131.
132.
The effective use of activated charcoal as an oral adsorbent for primary treatment of acute poisoning was investigated in vitro by evaluating the characteristics of mexiletine, an anti-arrhythmic drug, adsorbed onto activated charcoal in the presence of sodium chloride solutions at various concentrations. The equilibrium amount of mexiletine adsorbed onto activated charcoal was increased by the addition of sodium chloride. In particular, there was a marked increase in the amount adsorbed from a solution of lower mexiletine concentration. The removal rate is another important factor in the evaluation of activated charcoal, and a rapid decrease of mexiletine concentration by the addition of sodium chloride was recognized. The acceleration of mexiletine adsorption onto activated charcoal by the addition of sodium chloride was due to the occurrence of salting-out. It could be concluded that the administration of activated charcoal suspended in saline solution was more effective in the primary treatment of acute poisoning by mexiletine overdose.  相似文献   
133.
The adsorption characteristics of 1,1,1,2‐tetrafluoroethane (HFC‐134a) on activated carbon were investigated to evaluate the recovery efficiency of HFC‐134a by six activated carbons (two granular activated carbons (GAC1 and GAC2), one high‐surface area activated carbon (HAC), and three activated carbon fibers (ACF10, ACF15, and ACF20)). HFC‐134a adsorption on the activated carbons increased with increase in the specific surface area and pore volume of the activated carbon. The differential heat of the HFC‐134a adsorption decreased with increase in the percentage of the micropore volume to the total pore volume. The adsorption model of HFC‐134a on the activated carbon could be based on the Langmuir model. The constant a of the Langmuir plot of HAC and ACF20 is smaller than GAC1 or GAC2 and ACF10 or ACF15, respectively. The constant Ws of HAC has the largest value. The constant a was correlated to the heat of adsorption. It is concluded that the largest amount of HFC‐134a was adsorbed on HAC, and the least amount of interaction occurred between HFC‐134a and the HAC. The amount of HFC‐134a adsorbed on the activated carbons over time was applied to the Sameshima equation. The adsorption rate constant of HFC‐134a on HAC was the largest. The HAC could be suitable for the recovery of HFC‐134a.  相似文献   
134.
Successful settlement of pelagic fish larvae into benthic juvenile habitats may be enhanced by a shortened settlement period, since it limits larval exposure to predation in the new habitat. Because the spatial distribution of marine fish larvae immediately prior to settlement versus during settlement was unknown, field experiments were conducted at Ishigaki Island (Japan) using light trap sampling and underwater visual belt transect surveys to investigate the spatial distribution patterns of selected pre- and post-settlement fishes (Acanthuridae, Pomacentridae, Chaetodonidae and Lethrinidae) among four habitats (seagrass bed, coral rubble, branching coral and tabular coral). The results highlighted two patterns: patterns 1, pre- and post-settlement individuals showing a ubiquitous distribution among the four habitats (Acanthuridae) and pattern 2, pre-settlement individuals distributed in all habitats, but post-settlement individuals restricted to coral (most species of Pomacentridae and Chaetodontidae) or seagrass habitats (Lethrinidae). The first pattern minimizes the transition time between the larval pelagic stage and acquisition of a benthic reef habitat, the latter leading immediately to a juvenile lifestyle. In contrast, the second pattern is characterized by high settlement habitat selectivity by larvae and/or differential mortality immediately after settlement.  相似文献   
135.
A number of local populations of finless porpoises (Neophocaena phocaenoides) are widely distributed throughout the warm coastal waters of Asia. The Omura Bay population, consisting of approximately 300 individuals, is the smallest of five populations inhabiting Japanese waters. It is a relatively new population that established after the global warming that took place approximately 9000 years ago. To observe whether these porpoises appear in the major corridor to the ocean from Omura Bay, we used acoustic monitoring to record occurrences of finless porpoises from November 2007 to May 2009. A stereo acoustic event recorder recorded the intensity and the sound source direction of biosonar signals, providing independent traces of sound sources corresponding to each detected animal. A total of 226 individuals were detected over the 1.5-year monitoring period, of which 76% occurred at night and 73% occurred during March and April. We compared the presence of porpoises to the Japanese anchovy catch in Omura Bay and the Hario Strait over the same period. Results suggested that possible reductions in anchovy resources in the bay could attract porpoises to the outside of their normal habitat. In total, 70% of the porpoise recordings took place when the tidal current was moving out of Omura Bay. Porpoises might follow the prey that are transported out of the bay due to the strong outbound current. The finless porpoises confined to the bay might extend their swimming area if prey is available.  相似文献   
136.
Yohei Nakamura 《Marine Biology》2010,157(11):2397-2406
An extensive seagrass bed on a fringing coral reef at Amitori Bay (southern Ryukyu Islands) disappeared completely in 2009 after a typhoon. Seagrass bed loss had a significant negative influence on not only seagrass bed residents but also commercially important coral reef fishes that utilize seagrass beds as nurseries or feeding grounds. With seagrass bed loss, mean species’ richness and densities of overall seagrass bed fishes per transect decreased by more than 75 and 85%, respectively. Most of the affected fishes were benthivores, piscivores, detritivores, and herbivores. Of 21 dominant species, 13 disappeared completely and 4 showed severe reductions in densities following seagrass bed loss, whereas the densities of 4 bottom-dwelling gobies did not change significantly. Thus, this study demonstrated that most seagrass bed fishes lack the ability to adapt to seagrass habitat loss, suggesting that increasing global seagrass loss will cause serious reductions in seagrass-associated fishes and fishery resources.  相似文献   
137.
OBJECTIVE: To observe how PCDD/F and Co-PCB concentrations in breast milk relate to infant birthweights in Tokyo, Japan. STUDY DESIGN: Breast milk samples were collected from 240 mothers (aged 25-34years old) residing in Tokyo to measure the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs; 14 congeners), polychlorinated dibenzofurans (PCDFs; 15 congeners), and coplanar polychlorinated biphenyls (Co-PCBs; 12 congeners) in the breast milk fat. Individual milk samples (about 50ml) were obtained 30days after delivery, between the months of June and September in 1999 and 2000. The relationship of the infant birthweights with the PCDD/F and Co-PCB concentrations was observed. RESULTS: The birthweights were negatively correlated the concentrations of many of the PCDD/F and Co-PCB congeners, with the mean toxic equivalent quantities (TEQs) of the Co-PCBs, and with the sum of the PCDD, PCDF and Co-PCBs, although their correlation coefficients were less than 0.200. Multiple regression analysis showed octachlorodioxin was statistically significant explanatory variate. CONCLUSIONS: There were slight relationship between the dioxins levels of breast milk and the birthweights of the infants.  相似文献   
138.
Propolis is a natural resinous product collected by honeybees from certain plants. It has gained popularity as a food and alternative medicine. Poplar and Baccharis are well known as the source plants of European and Brazilian propolis, respectively. However, the propolis from Okinawa, Japan, contains some prenylflavonoids not seen in other regions such as Europe and Brazil, suggesting that the plant origin of Okinawan propolis is a particular plant that grows in Okinawa. To identify the plant origin of Okinawan propolis, we observed the behavior of honeybees as they collected material from plants and caulked it inside the hive. Honeybees scraped resinous material from the surface of plant fruits of Macaranga tanarius and brought it back to their hive to use it as propolis. We collected samples of the plant and propolis, and compared their constituents by high-performance liquid chromatography with a photo-diode array detector. We also compared their 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity. The chemical constituents and biological activity of the ethanol extracts of the plant did not differ from those of propolis. This indicates directly that the plant origin of Okinawan propolis is M. tanarius. S. K. and J. N. contributed equally to this work.  相似文献   
139.
Human hair samples from male and female people aged 6-85 years, as well as muscle of crabs (Callinectes sapidus and Callinectes bocourti) were collected from different fishing places along the Caribbean coastal shoreline of Colombia and analyzed for total mercury (T-Hg) in order to establish the impact of mercury-polluted sediments in Cartagena bay on the ecosystem. Hair T-Hg in inhabitants varied between 0.1 and 21.8 microg/g, with average and median of 1.52 microg/g and 1.1 microg/g, respectively. Differences between sampling locations were significant (P<0.01) and median values decreased in the order: Ca?o del Oro (1.5 microg/g)相似文献   
140.
Radiocarbon concentration in the atmosphere is significantly lower in areas where man-made emissions of carbon dioxide occur. This phenomenon is known as Suess effect, and is caused by the contamination of clean air with non-radioactive carbon from fossil fuel combustion. The effect is more strongly observed in industrial and densely populated urban areas. Measurements of carbon isotope concentrations in a study area can be compared to those from areas of clear air in order to estimate the amount of carbon dioxide emission from fossil fuel combustion by using a simple mathematical model. This can be calculated using the simple mathematical model. The result of the mathematical model followed in this study suggests that the use of annual rings of trees to obtain the secular variations of 14C concentration of atmospheric CO2 can be useful and efficient for environmental monitoring and modeling of the carbon distribution in local scale.  相似文献   
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