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Loizia Pantelitsa Neofytou Niki Zorpas Antonis A. 《Environmental science and pollution research international》2019,26(15):14766-14773
Environmental Science and Pollution Research - Food waste management (FWM) is considered to be an extremely important social issue besides an environmental one. Worldwide, it is estimated that 1.3... 相似文献
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Kostas?SagonasEmail author Niki?Karambotsi Aristoula?Bletsa Aikaterini?Reppa Panayiotis?Pafilis Efstratios?D.?Valakos 《Die Naturwissenschaften》2017,104(3-4):22
In caudal autotomy, lizards shed their tail to escape from an attacking predator. Since the tail serves multiple functions, caudal regeneration is of pivotal importance. However, it is a demanding procedure that requires substantial energy and nutrients. Therefore, lizards have to increase energy income to fuel the extraordinary requirements of the regenerating tail. We presumed that autotomized lizards would adjust their digestion to acquire this additional energy. To clarify the effects of tail regeneration on digestion, we compared the digestive performance before autotomy, during regeneration, and after its completion. Tail regeneration indeed increased gut passage time but did not affect digestive performance in a uniform pattern: though protein income was maximized, lipid and sugar acquisition remained stable. This divergence in proteins may be attributed to their particular role in tail reconstruction, as they are the main building blocks for tissue formation. 相似文献
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David W. Ostendorf Baoshan Xing Niki Kallergis 《Journal of contaminant hydrology》2009,106(3-4):118-130
At a former wood preservation plant severely contaminated with coal tar oil, in situ bulk attenuation and biodegradation rate constants for several monoaromatic (BTEX) and polyaromatic hydrocarbons (PAH) were determined using (1) classical first order decay models, (2) Michaelis–Menten degradation kinetics (MM), and (3) stable carbon isotopes, for o-xylene and naphthalene. The first order bulk attenuation rate constant for o-xylene was calculated to be 0.0025 d− 1 and a novel stable isotope-based first order model, which also accounted for the respective redox conditions, resulted in a slightly smaller biodegradation rate constant of 0.0019 d− 1. Based on MM-kinetics, the o-xylene concentration decreased with a maximum rate of kmax = 0.1 µg/L/d. The bulk attenuation rate constant of naphthalene retrieved from the classical first order decay model was 0.0038 d− 1. The stable isotope-based biodegradation rate constant of 0.0027 d− 1 was smaller in the reduced zone, while residual naphthalene in the oxic part of the plume further downgradient was degraded at a higher rate of 0.0038 d− 1. With MM-kinetics a maximum degradation rate of kmax = 12 µg/L/d was determined. Although best fits were obtained by MM-kinetics, we consider the carbon stable isotope-based approach more appropriate as it is specific for biodegradation (not overall attenuation) and at the same time accounts for the dominant electron-accepting process. For o-xylene a field based isotope enrichment factor εfield of − 1.4 could be determined using the Rayleigh model, which closely matched values from laboratory studies of o-xylene degradation under sulfate-reducing conditions. 相似文献
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Hult M Martínez Canet MJ Johnston PN Komura K 《Journal of environmental radioactivity》2002,60(3):307-318
During the JCO-accident in Tokai-mura in 1999, the surrounding village was irradiated by an uncontrolled neutron flux. At some locations in that village, the thermal neutron flux was determined retrospectively by measurement of the very low activity of 51Cr and 60Co in stainless-steel spoons using gamma-ray spectrometry in underground laboratories. Activities determined in the HADES underground facility are presented here, together with calibrations performed using a well-defined thermal neutron flux to directly estimate the fluence of thermal neutrons independent of most assumptions. The results show measurable 51Cr in three samples and 60Co in four samples taken from locations at distances of up to 430m from the accident location despite the elapse of 4 half-lives of 51Cr before measurement. Effects of air transport of the samples were considered and shown to be negligible. 相似文献
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Ken Sasaki Kazuhisa Yamasaki Koji Tsuchida Takashi Nagao 《Die Naturwissenschaften》2009,96(5):625-629
In social insects, biogenic amines are thought to play regulatory roles in the transition between reproductive states in females.
To determine the effect of dopamine on the reproductive development of workers in primitively eusocial societies, isolated
workers of the paper wasp Polistes chinensis were supplied with oral dopamine. Ovarian development was accelerated in dopamine-fed workers as compared to control workers
of the same age fed only sucrose solution. Oral dopamine increased brain levels of dopamine and its metabolite (N-acetyldopamine). Brain levels of tyramine or octopamine were also increased by dopamine application in one of two colonies;
levels of the tyramine metabolite N-acetyltyramine were unchanged. These results indicate that dopamine plays a gonadotropic role in isolated workers in the
primitively eusocial wasp, similar to the gonadotropic role previously reported for juvenile hormone. This is the first study
to report effects of dopamine on ovarian development in workers of the paper wasp. 相似文献
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Atsushi Nanami Taku Sato Takayuki Takebe Kazuhisa Teruya Kiyoshi Soyano 《Marine Biology》2013,160(6):1511-1517
Microhabitat associations are considered to be important for juvenile survivorship and growth of coral reef fishes. The aim of the study was to quantify microhabitat associations between juvenile and adult white-streaked grouper Epinephelus ongus, which supports important fisheries in coral reef areas. Underwater observations revealed that most juveniles were found in bottlebrush Acropora spp., staghorn Acropora spp. and coral rubble and there was a significant positive use of bottlebrush Acropora spp. and a significant negative use of coral rubble. For adults, most individuals were found in bottlebrush Acropora spp. and staghorn Acropora spp., and there was a significant positive use of staghorn Acropora spp. and significant negative use of coral rubble. A habitat choice experiment by using pre-settlement individuals revealed that both bottlebrush Acropora spp. and staghorn Acropora spp. were used as settlement sites, whereas coral rubble was rarely used as a settlement site. Results of the study suggest that juvenile and adult E. ongus showed significantly positive microhabitat associations with bottlebrush Acropora spp. and staghorn Acropora spp., respectively, in the field. Bottlebrush Acropora spp. has smaller inter-branch spaces than staghorn Acropora spp., which could drive patterns of microhabitat associations. In addition, post-settlement processes such as predation may influence the spatial distribution of juveniles. Because Acropora corals are very susceptible to coral bleaching, we predict that rising temperatures from climate change will negatively impact populations of E. ongus. 相似文献
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In this perspective, we present how three initial landmark papers on urban sustainability research contributed to the larger sustainability science scholarship and paved the way for the continued development of urban sustainability research. Based on this, we propose three conceptual innovation pathways to trace the progression of urban sustainability science: First, urban sustainability from a system’s perspective, meaning that urban sustainability requires integrative solutions to work in the tripled social-ecological-technological system setting. Second, urban sustainability from a (people and place) relational perspective, meaning urban sustainability is a contested and dynamic social-ecological contract of cities. As a governance mission, urban sustainability requires evidence from research that can inform coordinated action to bridge people, places, meanings, visions and ecosystems. Third, urban sustainability from a transformative science perspective, meaning that for urban sustainability to be achieved and progressed, deep transformations are required in systems, relations, policies and governance approaches. Our proposal for the future of urban sustainability science centres on emphasizing the relevance and policy applicability of systems’ thinking, value and place thinking and transitions/transformations thinking as fundamental to how knowledge is co-produced by research science, policy and society and becomes actionable. 相似文献
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Olga S. Arvaniti Marilena E. Dasenaki Alexandros G. Asimakopoulos Niki C. Maragou Vasilios G. Samaras Korina Antoniou Georgia Gatidou Daniel Mamais Constantinos Noutsopoulos Zacharias Frontistis Nikolaos S. Thomaidis Athanasios S. Stasinakis 《Frontiers of Environmental Science & Engineering》2022,16(11):148