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191.
Pascal D. Leroy Ahmed Sabri Fran?ois J. Verheggen Fr��d��ric Francis Philippe Thonart Eric Haubruge 《Chemoecology》2011,21(3):113-122
In natural environment, semiochemicals are involved in many interactions between the different trophic levels involving insects,
plants and hosts for parasitoids or prey for predators. These volatile compounds act as messengers within or between insect
species, inducing particular behaviours, such as the localisation of a source of food, the orientation to an adequate oviposition
site, the selection of a suitable breeding site and the localisation of hosts or prey. In this sense, bacteria have been shown
to play an important role in the production of volatile compounds which ones act as semiochemicals. This review, focusing
on the semiochemically mediated interactions between bacteria and insects, highlights that bacterial semiochemicals act as
important messengers for insects. Indeed, in most of the studies reported here, insects respond to specific volatiles emitted
by specific bacteria hosted by the insect itself (gut, mouthparts, etc.) or present in the natural environment where the insect
evolves. Particularly, bacteria from the families Enterobacteriaceae, Pseudomonaceae and Bacillaceae are involved in many
interactions with insects. Because semiochemicals naturally produced by bacteria could be a very interesting option for pest
management, advances in this field are discussed in the context of biological control against insect pests. 相似文献
192.
Elaine S. Carvalho Rubén J. Sánchez Maria I. B. Tavares álano C. Lam?nica 《Journal of Polymers and the Environment》2010,18(4):661-667
The chemical modification of Acrylamidomethyl Cellulose Acetate Propionate (AMCAP) was carried out by radical addition of
acrylic acid. The structural modification was confirmed with the aid of FTIR, MS and NMR techniques. Thermal properties of
hydrophilic cellulose derivative (AMCAP–H2O2) such as glass transition (Tg 153 °C) and thermal stability (372.7 °C) were determined by DSC and TGA techniques, respectively. These thermal properties
confirmed the introduction of carboxylic groups into AMCAP structure, which causes an impact in their properties. The AMCAP–H2O2 shows minor contact angle compared to AMCAP, giving a more hydrophilic characteristic, due to acrylic acid addition into
the side chains of AMCAP polymer. 相似文献
193.
Negative effects of noise on individuals, the inevitable result of urbanization, have become a significant urban problem in our day. Introduction of an approach to the noise problem on an urban-planning scale lightens the burden of measures required to be taken against noise at the stages of regional and developmental planning. Stadiums, which should be also evaluated from the point of noise problem when planning decisions are made on the urban planning scale, may cause very serious problems differing depending on the region they are located in. In this article, various dimensions of the noise problem caused by stadiums have been exemplified by making an assessment on Ali Sami Yen football stadium located in Mecidiyeköy district which is among important residential and commercial centres of ?stanbul or Turkey. When the simulation results obtained for ordinary days and match days are evaluated, it has been found out that the people living in the area are exposed to noise levels substantially exceeding the acceptable values. Results of the survey conducted in the area have clearly revealed the existence of noise problem, too. 相似文献
194.
Bart Victor 《组织行为杂志》1990,11(3):187-199
Differentiation, interdependence, and interest conflict between work units were investigated as determinants of managerial selection between coordination strategies. One hundred and four MBA students with managerial experience participated in a simulation in which they were required to select a strategy to manage systematically different relations between work units. Findings reveal a three-way interaction between differentiation, interdependence, and interest conflict affecting the degree of cooperation and centralization of selected strategies. The formalization of such strategies was affected by an interaction between differentiation and interest conflict. Implications for theory and practice are described. 相似文献
195.
196.
197.
ABSTRACT The study explores how glocalization of COVID-19 responses affects the management of the pandemic in Africa. Using data from 20 selected African countries, the study found that the reliance on local medicines alongside other salient global initiatives for containment of COVID-19 is effective in managing the pandemic in Africa. It concluded that despite the high vulnerabilities of African countries to COVID-19, the glocal approach has yielded positive outcomes by increasing the number of patients that recover from COVID-19 and scaling down the fatalities compared with the other regions. 相似文献
198.
Contamination of soil and groundwater by trinitrotoluene (TNT) is a widespread problem confronting military bases and ammunition manufacturing facilities throughout the United States. Phytoremediation provides a promising treatment of TNT-contaminated groundwater and wastewater because many plants contain the necessary enzymes to degrade explosives such as TNT. Two phytoremediation methods are proposed in this article: controlled reactors and constructed wetlands. Controlled reactors provide greater control of operating parameters, a reduced possibility of contaminant migration, control of animals feeding on the plants, and minimization of competition from other plant species. Constructed wetlands have relatively low capital costs, and the wetland becomes a desirable ecological resource. Because cost, as opposed to reactor size, appears to be the most significant factor for military base cleanup, this project focused on the constructed wetland approach. To estimate the disappearance of TNT and its breakdown products from a constructed wetland, a first-order, nonreversible reaction, plug-flow, finite-difference model was developed. Batch scale experiments were conducted to define disappearance kinetics for individual chemical species. The results of the model suggest that reasonably sized wetlands may be used to treat a wastestream with an influent TNT concentration of 2.25 ppm at flow rates ranging from 10 to 5,000 gpm. Economic comparisons to other published costs for competing technologies are promising. 相似文献
199.
Hong?ZhengEmail author Yoshitaka?Nitta Isamu?Yokota 《Journal of Material Cycles and Waste Management》2004,6(2):153-161
In this article, the systems for the collection and intermediate processing of used beverage cans (UBCs) are compared and analyzed, focusing on the time taken and the cost of processing, the energy consumption, and the emissions of CO2, SO
x
, and NO
x
, during the process. We found that cases where the UBCs were crushed in the discharging process gave better results, and how the UBCs were collected was the most important factor. It was more desirable to treat UBCs in one place than in two places. When the transportation distance was longer, the pressed form of UBCs was more convenient. When the transportation distance was short, the original form, the crushed form, and the shredded form of UBCs were all suitable. That is, the contribution of the transportation process to the evaluation was large when the transport distance was long, and the contribution of the treatment process was large when the transport distance was short. 相似文献
200.
Atsushi?TerazonoEmail author Aya?Yoshida Jianxin?Yang Yuichi?Moriguchi Shin-ichi?Sakai 《Journal of Material Cycles and Waste Management》2004,6(2):82-96
In this article, we clarify the current status of Japanese exports and Chinese imports of secondary resources. A total of around 10 million metric tons (t) of secondary resources are exported annually from Japan to China, Hong Kong, and Korea. Hong Kong plays the role of a transshipment point, especially regarding the trade in plastic waste, and China imports much from the USA and Japan, often through Hong Kong. The secondary resources exported from Japan include both byproducts from manufacturing processes and end-of-life products or materials. The great demand in China, and the difference in prices between countries, drive this transboundary shipment, although Japan has enacted various recycling laws that were implicitly intended to promote domestic recycling. In China, the imported secondary resources are recycled, usually by means of primitive and low-cost hand labor. The greatest concern is whether there are still improper (illegal or polluting) recycling activities in China. International material cycles should prevent environmental pollution and ensure efficient resource utilization. To that end, the following measures are needed: cooperative control of the trade of secondary resources between countries, the alignment of domestic laws with the regulations in other countries based on the actual trade activities, and the realization of sound practices for global resources management. 相似文献