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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.
Decolorization of oxygen-delignified bleaching effluent (abbreviated as OBE) and biobleaching of oxygen-delignified kraft pulp (OKP) were conducted using a non-white rot fungus Geotrichum candidum Dec 1 (abbreviated as Dec 1) which has ability to decolorize various synthetic dyes and molasses. Dec 1 decolorized up to 77% of OBE for 6 days. In addition, Dec 1 increased the brightness of OKP from 47.8% to 51.2% and decreased the kappa value of OKP from 12.4 to 10.4 points during a 6-day incubation period at a 25% of pulp-concentration. At 2% pulp-concentration, the brightness of OKP increased by 13% and the kappa value of OKP decreased by 4 points only for a 3-day incubation period. When the decolorized OBE was used for bleaching of OKP, the brightness of OKP increased to 62.7% under the shaking culture to a 2% pulp-concentration using culture fluid of decolorized OBE. It was revealed that Dec 1 is a potential to apply for decolorization of wastewater and biobleaching of pulp in paper-mills. 相似文献
4.
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
5.
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
6.
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
7.
In this study, we propose a "washing-calcination-conversion of washed fly ash into cement material with bottom ash" (WCCB) system to reduce the amount of fly ash that must be specially treated so it can be used as raw cement material. Calcium hydroxide (Ca(OH)2) is widely used in air-pollution control devices of incinerators while sodium bicarbonate (NaHCO3) is not. We conducted single-, double-, and triple-washing experiments to compare the washing characteristics of two types of fly ash. Unlike NaHCO3 fly ash, Ca(OH)2 fly ash has almost twice as much washed residue and almost 2.5 times more chlorine after the same washing procedure. After washing once, the washing frequency is also important for NaHCO3 fly ash, while the mixing time and liquid/solid ratio are more critical for Ca(OH)2 fly ash. The use of NaHCO3 is more suitable for the WCCB system. 相似文献
8.
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
9.
Yuya Takuwa Tadao Matsumoto Kazuyuki Oshita Masaki Takaoka Shinsuke Morisawa Nobuo Takeda 《Journal of Material Cycles and Waste Management》2009,11(4):305-311
Because landfill gas (LFG) contains an abundance of methane, the utilization of LFG as a renewable energy source is becoming
popular in many countries. LFG, however, contains various trace constituents, some of which may pose problems during utilization.
For example, siloxanes and halogenated volatile organic compounds (VOCs) can cause difficulties when present in the fuel of
gas engines. In addition, many VOCs and mercury have harmful effects on human health, especially on the health of workers
at landfill sites and people living near the landfills. Energy recovery from LFG is expected to make great progress in the
near future, particularly in Asia, but we found little information on the trace constituents of LFG in this region. Therefore,
we sought to characterize the trace components in LFG generated in two landfill sites in China and one site in Japan, to determine
the typical concentrations of these trace components in LFG, and to compare their concentrations among landfill sites in Asia.
We concluded that the trace components in LFG at the sites studied were mainly siloxanes generated from sewage sludge and
harmful benzene, toluene, ethylbenzene, and xylene compounds from petroleum products. 相似文献
10.
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