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1.
Communication by means of pheromones plays predominant roles in colony integration by social insects. However, almost nothing is known about pheromone processing in the brains of social insects. In this study, we successfully applied intracellular recording and staining techniques to anatomically and physiologically characterize brain neurons of the ant Camponotus obscuripes. We identified 42 protocerebral neurons that responded to undecane and/or formic acid, components of alarm pheromones that evoke attraction or evasive behavior, respectively. Notably, 30 (71%) of these neurons were efferent (output) or feedback neurons of the mushroom body, and many of these exhibited different responses to formic acid and undecane. Eight of the remaining 12 neurons had arborizations in the lateral and/or medial protocerebrum, which receive terminations of efferent neurons of the mushroom body and from which premotor descending neurons originate. The remaining four neurons were bilateral neurons that connect lateral accessory lobes or dorsal protocerebrums of both hemispheres. We suggest that the mushroom body of the ant participates in the processing of alarm pheromones. Seventeen (40%) of 42 neurons exhibited responses to nonpheromonal odors, indicating that the pheromonal and nonpheromonal signals are not fully segregated when they are processed in the protocerebrum. This may be related to modulatory functions of alarm pheromones, i.e., they change alertness of the ant and change responses to a variety of sensory stimuli. 相似文献
2.
Some polyclads associate with other marine invertebrates such as gastropods, but how these associations evolve is not well understood. This study examined the relationships between a polyclad, Stylochoplana pusilla, and six species of snails in 10 eulittoral sites in Mutsu Bay, northern Japan, in 2010 and 2011. Of the six potential host snail species, Monodonta labio was present at all sites and the prevalence of S. pusilla in the snails’ mantle cavities overall was 82.6 %. Four other snail species occurred at five or six sites in comparable densities, but of these, only Chlorostoma turbinatum and Omphalius rusticus had S. pusilla in their mantle cavities (prevalence of 42.0 and 15.4 %). A congener of M. labio, Monodonta neritoides, occurred at only one site and had no S. pusilla. The mantle, which provides habitat space for S. pusilla, was proportionally the longest in M. labio. In laboratory experiments, the flatworms preferentially entered M. labio over other snail species with the same mantle length. Observed vertical distributions of snails in the littoral zone indicate that M. labio is present in the eulittoral at both high and low tides, while C. turbinatum and O. rusticus are usually found in the sublittoral. In an evolutionary sense, the relationship between S. pusilla and its host may have developed as a mechanism for the flatworm to avoid predation by living in the eulittoral and to avoid desiccation by establishing commensal relationships with certain snails. 相似文献
3.
Ishii N Sakashita T Takeda H Kubota Y Fuma S Doi M Takahashi S 《Journal of environmental radioactivity》2007,97(2-3):159-167
Extracellular DNA is omnipresent in aquatic environments and is thought to be a genetic material for horizontal gene transformation between microorganisms. We studied the impact of gamma irradiation on the transformation efficiency (transformants number per ng of DNA per ml) of extracellular DNA. Plasmid pEGFP as a model extracellular DNA was irradiated by gamma rays. The transformation efficiency decreased with the increase in radiation dose. A total dose of 10Gy is normally not lethal for microorganisms but certainly affects the transformation efficiency of extracellular DNA. The decrease in the efficiency would be induced by strand breaks of extracellular DNA because the yield of both single-strand breaks (SSBs) and double-strand breaks (DSBs) increased with the increase in radiation dose. The relative transformation efficiency of SSBs and DSBs to that of covalently closed circles (CCCs) was 30.3% and 0.2%, respectively. This impact on natural transformation suggests an inability of microorganisms to acquire new characteristics which should be normally acquired. 相似文献
4.
Lauren Withycombe Keeler Arnim Wiek Daniel J. Lang Makoto Yokohari John van Breda Lennart Olsson Barry Ness Jordi Morato Jordi Segalàs Pim Martens Luis A. Bojórquez-Tapia James Evans 《Sustainability Science》2016,11(5):749-762
A promising approach for addressing sustainability problems is to recognize the unique conditions of a particular place, such as problem features and solution capabilities, and adopt and adapt solutions developed at other places around the world. Therefore, research and teaching in international networks becomes critical, as it allows for accelerating learning by sharing problem understandings, successful solutions, and important contextual considerations. This article identifies eight distinct types of research and teaching collaborations in international networks that can support such accelerated learning. The four research types are, with increasing intensity of collaboration: (1) solution adoption; (2) solution consultation; (3) joint research on different problems; and (4) joint research on similar problems. The four teaching types are, with increasing intensity of collaboration: (1) adopted course; (2) course with visiting faculty; (3) joint course with traveling faculty; and (4) joint course with traveling students. The typology is illustrated by extending existing research and teaching projects on urban sustainability in the International Network of Programs in Sustainability, with partner universities from Europe, North America, Asia, and Africa. The article concludes with challenges and strategies for extending individual projects into collaborations in international networks. 相似文献
5.
Makoto Yoshihara Guido Grause Tomohito Kameda Toshiaki Yoshioka 《Journal of Material Cycles and Waste Management》2010,12(3):264-270
The recycling of poly(vinyl chloride) (PVC) is one of the most important issues in the treatment of waste plastics. To improve PVC recycling, it is necessary to develop new recycling techniques, including new techniques for the dechlorination of chlorine-containing polymers. It has been established that wet dechlorination of PVC in NaOH/ethylene glycol solution is more effective than dry dechlorination. In this study, the wet process was used, and the chemical modification of PVC by nucleophilic substitution was considered for upgrading waste PVC. Chlorine was substituted in solution by several nucleophilic reagents, thus changing the properties of PVC. The reaction of PVC in Na2S/ethylene glycol solution at 170°C resulted in the formation of a mixture comprising 32% elimination and 26% substitution products. The scanning electron microscopy/energy dispersive X-ray spectroscopy mappings and elementary analysis of PVC indicated that this chlorine-substitution process led to cross-linking by sulfur. 相似文献
6.
Towards institutional analysis of sustainability science: a quantitative examination of the patterns of research collaboration 总被引:2,自引:2,他引:0
This paper examines quantitatively the patterns of collaboration over geographical boundaries in the emerging field of sustainability
science by empirically analyzing the bibliometric data of scientific articles. The results indicate that an increasing number
of countries are engaged in research on sustainability, with the proportion of articles published through international collaboration
rising as well. The number of countries engaged in international collaboration on sustainability research has been increasing,
and the diversity of countries engaged in research collaboration beyond national borders is also increasing. The geographical
patterns of collaboration on sustainability show that research collaboration tends to be conducted between countries which
are geographically located closely, suggesting that communication and information exchange might be limited within the regional
clusters. The focused fields of research activities on sustainability are significantly different between countries, as each
country has its focused fields of research related to sustainability. The specialization of research activities is also observed
in international collaboration. While these patterns of international collaboration within regional clusters focusing on specific
fields could be effective in promoting the creation, transmission, and sharing of knowledge on sustainability utilizing the
already existing regional networks, they could pose a serious obstacle to collecting, exchanging, and integrating diverse
types of knowledge, especially when it is necessary to deal with problems involving large-scale complex interactions with
long-term implications, such as climate change. It would be of critical importance to establish inter-regional linkages by
devising appropriate institutional arrangements for global research collaboration on sustainability science. 相似文献
7.
Hisato Yano Makoto Shoda 《Journal of the Air & Waste Management Association (1995)》2013,63(3):324-331
ABSTRACT The investigation of an appropriate organic solvent removal apparatus for installation in a newly reconstructed print shop as a countermeasure for preventing the exhaust of organic solvents was conducted. The selection of an organic solvent removal apparatus was made after bench-scale tests of the activated carbon adsorption method and the catalytic oxidation method, both of which are effective for the removal of organic solvents, were performed on the actual exhaust gas at the print shop. The results showed that both methods were efficient enough to be applied to the removal of organic solvents, but the activated carbon adsorption method had many drawbacks, such as the need for frequent replacement of activated carbon and complex maintenance. For the catalytic oxidation method, running costs are high, but there are many merits, such as that the catalysts do not have to be replaced as often and maintenance is simple. After considering these factors, a catalytic oxidation removal apparatus was installed at the new print shop. In the results of the substantiation test on the actual apparatus using mixed catalysts of platinum and manganese plus copper, the removal efficiency was 97.998.7% and the concentration of the outlet exhaust gas was about 10 ppm (the average concentration of the inlet exhaust gas was 528 ppm) at a space velocity of 30,000 hr-1 and a reaction temperature of 200 °C. The results of this study were substantiated. 相似文献
8.
Effects of acute γ-irradiation on the aquatic microbial microcosm in comparison with chemicals 总被引:1,自引:1,他引:0
Shoichi Fuma Nobuyoshi Ishii Hiroshi Takeda Kiriko Miyamoto Kei Yanagisawa Kazutaka Doi Isao Kawaguchi Nobuyuki Tanaka Yuhei Inamori Gennady G. Polikarpov 《Journal of environmental radioactivity》2009,100(12):1027-1033
Effects of acute γ-irradiation were investigated in the aquatic microcosm consisting of green algae (Chlorella sp. and Scenedesmus sp.) and a blue–green alga (Tolypothrix sp.) as producers; an oligochaete (Aeolosoma hemprichi), rotifers (Lecane sp. and Philodina sp.) and a ciliate protozoan (Cyclidium glaucoma) as consumers; and more than four species of bacteria as decomposers. At 100 Gy, populations were not affected in any taxa. At 500–5000 Gy, one or three taxa died out and populations of two or three taxa decreased over time, while that of Tolypothrix sp. increased. This Tolypothrix sp. increase was likely an indirect effect due to interspecies interactions. The principal response curve analysis revealed that the main trend of the effects was a dose-dependent population decrease. For a better understanding of radiation risks in aquatic microbial communities, effect doses of γ-rays compared with copper, herbicides and detergents were evaluated using the radiochemoecological conceptual model and the effect index for microcosm. 相似文献
9.
Hideto Yoshida Kazuaki Takahashi Nobuo Takeda Shin-ichi Sakai 《Journal of Material Cycles and Waste Management》2009,11(3):229-243
We summarize the measures taken by the Japanese government to prevent the emission of dioxins and polychlorinated biphenyls
(PCBs) into the environment. Because incineration is the main method of waste management in Japan, reducing the amount of
dioxins emitted from waste incinerators is an essential aspect of proper waste treatment. Intensive measures to prevent the
formation of dioxins at the source have been implemented, with a focus on waste treatment methods and improving comprehensive
management. The efforts have been very successful, with a 95% reduction in the amount of dioxins emitted between 1997 and
2003. The toxicity of PCBs has been monitored with keen interest since the Yusho incident. Unfortunately, treatment facilities
for PCB wastes were not built until long after PCBs had been removed from use, and PCB wastes remained in storage in an untreated
state. The Japanese government has promoted the construction of facilities for treating PCB wastes, and five such facilities
have commenced operations. To more completely eradicate dioxins, a future challenge will be to reduce the amount of PCB-derived
dioxins, which are persistent in the environment and have a long exposure pathway from the environment media to the organism
and the human body. 相似文献
10.
Shinya Inazumi Hiroyasu Ohtsu Yu Otake Makoto Kimura Masashi Kamon 《Journal of Material Cycles and Waste Management》2009,11(1):55-64
An evaluation method that can express the local leakage of leachate from joint sections in steel pipe sheet pile (SPSP) cutoff
walls is discussed in this study. In particular, the evaluation of environmental feasibility (containment of leachates containing
toxic substances) considering a three-dimensional arrangement and hydraulic conductivity distribution of the joint sections
in the SPSP cutoff wall is compared with an evaluation that uses the equivalent hydraulic conductivity. This equivalent hydraulic
conductivity assumes that the joint section and the steel pipe are integrated; therefore, the hydraulic conductivity is substituted
with a uniform permeable layer. However, in an evaluation that employs the equivalent hydraulic conductivity, it is difficult
to consider the local leakage of leachate containing toxic substances from the joint sections in the SPSP cutoff wall. It
was established that evaluations of the environmental feasibility of SPSP cutoff walls with joint sections must take into
account the local leakage of leachates containing toxic substances from the joint sections. Also, it was clarified that technologies
that lower the hydraulic conductivities of joint sections in SPSP cutoff walls and also facilitate the use of sparser joint
arrangements contribute significantly to increasing the environmental feasibility of SPSP cutoff walls at landfill sites. 相似文献