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191.
Mark K. Greco Dorothee Hoffmann Anne Dollin Michael Duncan Robert Spooner-Hart Peter Neumann 《Die Naturwissenschaften》2010,97(3):319-323
Workers from social insect colonies use different defence strategies to combat invaders. Nevertheless, some parasitic species
are able to bypass colony defences. In particular, some beetle nest invaders cannot be killed or removed by workers of social
bees, thus creating the need for alternative social defence strategies to ensure colony survival. Here we show, using diagnostic
radioentomology, that stingless bee workers (Trigona carbonaria) immediately mummify invading adult small hive beetles (Aethina tumida) alive by coating them with a mixture of resin, wax and mud, thereby preventing severe damage to the colony. In sharp contrast
to the responses of honeybee and bumblebee colonies, the rapid live mummification strategy of T. carbonaria effectively prevents beetle advancements and removes their ability to reproduce. The convergent evolution of mummification
in stingless bees and encapsulation in honeybees is another striking example of co-evolution between insect societies and
their parasites. 相似文献
192.
A better understanding of corporate strategy under regulatory uncertainty enables policy makers to improve policy making efficiency and enhance regulations’ effectiveness. Based on a review of the literature on policy formulation, we propose that regulatory uncertainty is characterized by a dependence on political negotiation, a discrete scenario structure, and a discontinuous resolution. Data from a worldwide survey show that firms pursue response strategies to regulatory uncertainty that address these characteristics by participating in policy making and increasing strategic flexibility. Surprisingly, the results also show that regulatory uncertainty only partly causes firms to postpone strategic decisions. We find that existing regulation and a need to act quickly despite regulatory uncertainty are opposed to the pursuit of a postponement strategy. We conclude that improving the mechanisms by which firms participate in early stages of the policy making process could enable them to operate in a more target-oriented manner, allow for more efficient policy implementation, and increase a regulation's effectiveness. 相似文献
193.
Müller Irene Althof Nadine Hoffmann Bernd Klaus Christine Schilling-Loeffler Katja Falkenhagen Alexander Johne Reimar 《Food and environmental virology》2023,15(1):32-42
Food and Environmental Virology - Infection with the tick-borne encephalitis virus (TBEV) can cause meningitis, meningoencephalitis and myelitis in humans. TBEV is an enveloped RNA virus of the... 相似文献
194.
Gregory S. Douglas Jeffery H. Hardenstine Roopa Kamath Deyuan Kong Robert E. Hoffmann Sara McMillen 《补救:环境净化治理成本、技术与工艺杂志》2020,30(4):27-37
Bioremediation is a proven alternative for remediating petroleum‐impacted soils at exploration and production (E&P) sites. Monitoring remediation performance can involve detection and quantification of biodegradation resistant compounds such as C3017α(H),21β(H)‐hopane, which requires the use of gas chromatography with mass spectrometry detection (GC/MS). Due to the remoteness of many E&P sites, this technology is not always available, and alternative methods are needed to provide reliable quantitative measurements of petroleum remediation efficiency. This study provides a detailed chemical characterization of lacustrine‐sourced crude oils and a technical basis for measuring the effectiveness of bioremediation efforts for soil impacted by those crudes. We show that the novel isoprenoid hydrocarbon botryococcane is relatively stable in lacustrine‐sourced crude oils compared with C3017α(H),21β(H)‐hopane under moderate biodegradation conditions generally observed in field samples. We have also demonstrated that, due to the stability and relatively elevated concentration of botryococcane in lacustrine oils, it can be reliably measured using the more cost‐effective and available GC/FID methodology, and thereby be used to monitor the progress of ongoing soil bioremediation activities at remote sites. 相似文献
195.
Sophie M. E. Marsh Michael Hoffmann Neil D. Burgess Thomas M. Brooks Daniel W. S. Challender Patricia J. Cremona Craig Hilton-Taylor Flore Lafaye de Micheaux Gabriela Lichtenstein Dilys Roe Monika Böhm 《Conservation biology》2022,36(2):e13844
Unsustainable exploitation of wild species represents a serious threat to biodiversity and to the livelihoods of local communities and Indigenous peoples. However, managed, sustainable use has the potential to forestall extinctions, aid recovery, and meet human needs. We analyzed species-level data for 30,923 species from 13 taxonomic groups on the International Union for Conservation of Nature Red List of Threatened Species to investigate patterns of intentional biological resource use. Forty percent of species (10,098 of 25,009 species from 10 data-sufficient taxonomic groups) were used. The main purposes of use were pets, display animals, horticulture, and human consumption. Intentional use is currently contributing to elevated extinction risk for 28–29% of threatened or near threatened (NT) species (2752–2848 of 9753 species). Intentional use also affected 16% of all species used (1597–1631 of 10,098). However, 72% of used species (7291 of 10,098) were least concern, of which nearly half (3469) also had stable or improving population trends. The remainder were not documented as threatened by biological resource use, including at least 172 threatened or NT species with stable or improving populations. About one-third of species that had use documented as a threat had no targeted species management actions to directly address this threat. To improve use-related red-list data, we suggest small amendments to the relevant classification schemes and required supporting documentation. Our findings on the prevalence of sustainable and unsustainable use, and variation across taxa, can inform international policy making, including the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, the Convention on Biological Diversity, and the Convention on International Trade in Endangered Species. 相似文献
196.
Deming ZHAO Jie CHENG Michael R. HOFFMANN 《Frontiers of Environmental Science & Engineering》2011,5(1):57-64
Aqueous solutions of phenol were oxidized by hydrogen peroxide assisted by microwave (MW) irradiation. A simple kinetic model for the overall degradation of phenol in the presence of excess H2O2 is proposed in which the degradation rate of phenol is expressed as a linear function of the concentrations of phenol and H2O2. A detailed parametric study showed that the degradation rate of phenol increased with increasing [H2O2] until saturation was observed. Phenol degradation followed apparent zero-order kinetics under MW radiation or H2O2 oxidation. However, after 90 min of irradiation, the observed kinetics shifted to pseudo first order. The overall reaction rates were significantly enhanced in the combined MW/H2O2 system, mainly because microwave could accelerate H2O2 to generate hydroxyl radical (·OH) and other reactive oxygen intermediates. The observed synergetic effects of the MW/H2O2 process resulted in an increased in the net reaction rate by a factor of 5.75. When hydrogen peroxide is present in a large stoichiometric excess, the time required to achieve complete mineralization is reduced significantly. 相似文献
197.
Deming Zhao Jie Cheng Michael R. Hoffmann 《Frontiers of Environmental Science & Engineering in China》2011,5(1):57-64
Aqueous solutions of phenol were oxidized by hydrogen peroxide assisted by microwave (MW) irradiation. A simple kinetic model
for the overall degradation of phenol in the presence of excess H2O2 is proposed in which the degradation rate of phenol is expressed as a linear function of the concentrations of phenol and
H2O2. A detailed parametric study showed that the degradation rate of phenol increased with increasing [H2O2] until saturation was observed. Phenol degradation followed apparent zero-order kinetics under MW radiation or H2O2 oxidation. However, after 90 min of irradiation, the observed kinetics shifted to pseudo first order. The overall reaction
rates were significantly enhanced in the combined MW/H2O2 system, mainly because microwave could accelerate H2O2 to generate hydroxyl radical (·OH) and other reactive oxygen intermediates. The observed synergetic effects of the MW/H2O2 process resulted in an increased in the net reaction rate by a factor of 5.75. When hydrogen peroxide is present in a large
stoichiometric excess, the time required to achieve complete mineralization is reduced significantly. 相似文献
198.
Skraber Sylvain Gantzer Christophe Helmi Karim Hoffmann Lucien Cauchie Henry-Michel 《Food and environmental virology》2009,1(2):66-76
A filtration system, based on tangential flow filtration (TFF) followed by ultracentrifugation was developed in order to concentrate
simultaneously viruses and parasites from large volumes of water. For TFF, no pre-treatment of the membrane is performed but
a post-rinsing step using high pH-beef extract-based eluant. Applying our protocol to 20 l of surface waters spiked with vaccinal
poliovirus-1, ϕX174 and MS2 bacteriophages resulted in an averaged viral recovery of 75% by TFF and 91% by ultracentrifugation
(total viral recovery of 70%). Our protocol was further applied to 31 environmental samples including surface, ground and
drinking waters from the Grand Duchy of Luxembourg in order to assess the occurrence of protozoan parasites (Cryptosporidium parvum and Giardia lamblia (oo)cysts), pathogenic viruses (enterovirus, norovirus and adenovirus) and infectious bacteriophages (somatic coliphages
and F-specific phages) in these samples. High viral recovery rates of > 70% were confirmed concentrating environmental strains
of somatic and F-specific coliphages from non-spiked surface waters. Parasites and enteric viruses were detected in 86 and
40% of the surface waters used for drinking water production, respectively. Infectious bacteriophages were isolated from all
surface waters and in two out of seven (29%) groundwaters revealing a susceptibility of the corresponding wells to viral pollution.
TFF-based method proved to be efficient for surveying the occurrence of non-bacterial pathogens such as enteric viruses and
protozoan parasites in large volumes of environmental waters. 相似文献
199.
200.