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101.
Urastoma cyprinae is a species infecting the gills of several marine bivalves. Although there is some literature on this turbellarian, its life cycle remains unknown. In our work we have demonstrated that reproduction of U. cyprinae can be completed out of its host. More than 50% of turbellarians isolated from mussels (Mytilus galloprovincialis) secreted and cemented a cocoon to the well bottom during the first 72 h of incubation in seawater (34 salinity) at 14°C. Oviposition started at days 1–18 (average 4.8 days) and occurred in most cases inside the protective cocoon. Each Urastoma laid an average of 2.9 egg capsules (range 1–10) and 3.9 embryos were developed inside each egg capsule (range 1–11). Hatching started at days 20–43 (average 24 days). An average of 12.8 juvenile forms (range 1–64) escaped from the cocoon after hatching. The free-swimming juveniles showed a positive phototactic response and survived about a month after hatching. On the basis of our results, we propose a life cycle for U. cyprinae involving a sexual maturation parasitic period in the bivalve gills and a reproduction period including cocoon secretion, egg laying, and hatching that is entirely completed in the external environment.Communicated by S.A. Poulet, Roscoff  相似文献   
102.
The past decade has seen the rapid development of the tourist industry in Southeast Asia. There is increasing concern that tourism is highly affecting CO2 emissions, but the nature of the relationship is still unclear. The main target of this paper is to investigate the existence of a linear and/or nonlinear relationship between tourism and CO2 emissions in the five most important countries located in Southeast Asia, using the panel cointegration and pooled mean group techniques. The results indicate that tourism and CO2 emissions are cointegrated, implying that tourism affects CO2 emissions in the long run. Our findings support the nonlinear relationship between tourism and emissions as well as economic activities and CO2 emissions. Accordingly, an inverted U-shaped relationship exists between tourism and emissions confirming the existence of an Environmental Kuznets Curve in the Southeast Asian tourism industry. Furthermore, the empirical results show that economic activities and energy consumption greatly increase emissions.  相似文献   
103.
Rank-based sampling designs are powerful alternatives to simple random sampling (SRS) and often provide large improvements in the precision of estimators. In many environmental, ecological, agricultural, industrial and/or medical applications the interest lies in sampling designs that are cheaper than SRS and provide comparable estimates. In this paper, we propose a new variation of ranked set sampling (RSS) for estimating the population mean based on the random selection technique to measure a smaller number of observations than RSS design. We study the properties of the population mean estimator using the proposed design and provide conditions under which the mean estimator performs better than SRS and some existing rank-based sampling designs. Theoretical results are augmented with some numerical studies and a real-life example, where we also study the performance of our proposed design under perfect and imperfect ranking situations.  相似文献   
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In this research, an experimental study of reinforcing alumina nano-particles into the aluminum alloy matrix was implemented to verify the accuracy of modeling results obtained by feed forward neural networks. Artificial neural network combined with numerical technique were used to predict the various parameters of mechanical properties such as hardness, tensile and compressive yield stress, UTS and elongation percentage. Much experimentation were taken to discover a suitable number of hidden neurons, avoid detraction from the trainability and enable feed forward neural networks to solve more complex problems. The predictions were found to be consistent with experimental measurements.  相似文献   
107.

A wide variety of methods have been applied in indoor air to reduce the microbial load and reduce the transmission rate of acute respiratory diseases to personnel in healthcare sittings. In recent months, with the occurrence of COVID-19 pandemic, the role of portable ventilation systems in reducing the load of virus in indoor air has received much attention. The present study delineates a comprehensive up-to-date overview of the available photocatalysis technologies that have been applied for inactivating and removing airborne viruses. The detection methods for identifying viral particles in air and the main mechanisms involving in virus inactivation during photocatalysis are described and discussed. The photocatalytic processes could effectively decrease the load of viruses in indoor air. However, a constant viral model may not be generalizable to other airborne viruses. In photocatalytic processes, temperature and humidity play a distinct role in the inactivation of viruses through changing photocatalytic rate. The main mechanisms for inactivation of airborne viruses in the photocatalytic processes included chemical oxidation by the reactive oxygen species (ROS), the toxicity of metal ions released from metal-containing photocatalysts, and morphological damage of viruses.

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Environmental Science and Pollution Research - Accurate prediction of the dust concentration (DC) is necessary to reduce its undesirable environmental effects in different geographical areas....  相似文献   
109.

This study aims to investigate a practical bibliometric analysis and discuss its trends to evaluate the global scientific production of vermicompost research from 1993 to 2017 and explain its several advantages to our environment and waste management. The data were from the database of the Science Citation Index (SCI) published by the ISI Web of Science and illustrated by Excel and VOS viewer. According to the 2174 publications, this article was conducted based on four significant aspects, including publications growth trends, countries/territories, categories and journals, and keywords co-occurrence network analysis. This study revealed remarkable positive growth trends of the research and the number of articles related to vermicompost over the last 24 years with more countries participating in this field. Although the USA has the most collaboration with other countries, developing countries such as India, which was the most productive one, made significant progress in sharing articles within the study period. Based on analyses of dominant categories, the most common subject category was Environmental Science, and the most productive journal was Bioresource Technology. Finally, we analyzed author keywords to the extracted research article emphasis. The results showed that mainstream research claim vermicomposting with the help of Eisenia fetida earthworms which converts several wastes such as sewage sludge to a soil improvement fertilizer. It is an essential approach to eliminate heavy metals from the wastes and provide essential nutrients to improve the growth and yield of plants.

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110.
Environmental Science and Pollution Research - We reported the tin (II) tungstate nanoparticles as the photocatalyst and sensor modifier that were synthesized via chemical precipitation reaction...  相似文献   
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