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The International Journal of Life Cycle Assessment - Evaluation and monitoring systems are perceived as an effective tool to understand and improve the contribution of business activities to the...  相似文献   
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Monitoring the invasion process of the Asian tiger mosquito Aedes albopictus and its interaction with the contender Aedes aegypti, is critical to prevent and control the arthropod-borne viruses (i.e., Arboviruses) they transmit to humans. Generally, the superior ecological competitor Ae. albopictus displaces Ae. aegypti from most geographic areas, with the combining factors of biology and environment influencing the competitive outcome. Nonetheless, detailed studies asserting displacement come largely from sub-tropical areas, with relatively less effort being made in tropical environments, including no comprehensive research about Aedes biological interactions in Mesoamerica. Here, we examine contemporary and historical mosquito surveillance data to assess the role of shifting abiotic conditions in shaping the spatiotemporal distribution of competing Aedes species in the Republic of Panama. In accordance with prior studies, we show that Ae. albopictus has displaced Ae. aegypti under suboptimal wet tropical climate conditions and more vegetated environments within the southwestern Azuero Peninsula. Conversely, in the eastern Azuero Peninsula, Ae. aegypti persists with Ae. albopictus under optimal niche conditions in a dry and more seasonal tropical climate. While species displacement was stable over the course of two years, the presence of both species generally appears to fluctuate in tandem in areas of coexistence. Aedes albopictus was always more frequently found and abundant regardless of location and climatic season. The heterogenous environmental conditions of Panama shape the competitive outcome and micro-geographic distribution of Aedes mosquitoes, with potential consequences for the transmission dynamics of urban and sylvatic zoonotic diseases.

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Some studies have recently reported high diploid male frequencies in euglossine bees indicating possible population declines. We estimated the genetic variability and frequency of males that are diploid in five Colombian species of euglossine bees using allozyme markers. Expected heterozygosities ranged from 0.10 to 0.23. Diploid males were found in three species with frequencies ranging from 8 to 32 percent. Our results suggest that some species are more susceptible to environmental changes and anthropogenic pressure.  相似文献   
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Extracellular protons have been shown to modulate voltage-activated ionic channels. It has been proposed that synaptic modulation by exocytosed vesicular protons would be a characteristic feature of ribbon-type synapses. Type-I hair cells have a calyceal afferent junction with a diffusionally restricted synaptic cleft. These led us to study the action of extracellular pH changes on the voltage-activated Ca2+ and K+ currents evaluated using a whole-cell patch clamp in isolated cells. The amplitude of the Ca2+ and the K+ current were reduced by extracellular acidification, but without significant changes with extracellular alkalization. A shift in the voltage dependence to a more positive membrane potential was achieved at pH < 6.8. Our results shows that the presynaptic K+ and Ca2+ currents are modulated by protons, indicating that protons released along with an afferent neurotransmitter would participate as a feedback mechanism in type-I hair cells. Special issue article in honor of Dr. Ricardo Tapia.  相似文献   
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Pilot-scale reactor for aseptic solid-state cultivation   总被引:1,自引:0,他引:1  
Summary A new 50 l pilot scale reactor was used to carry out solid-state cultivations in sterile conditions using a forced aeration system with a planetary agitation device. The medium containing wheat bran wetted with a glucose solution was kept sterile for 8 days at 32°C.  相似文献   
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