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111.
K. Sigler D. Matoulková M. Dienstbier P. Gabriel 《Applied microbiology and biotechnology》2009,82(6):1027-1035
The net effect of increased wort osmolarity on fermentation time, bottom yeast vitality and sedimentation, beer flavor compounds,
and haze was determined in fermentations with 12° all-malt wort supplemented with sorbitol to reach osmolarity equal to 16°
and 20°. Three pitchings were performed in 12°/12°/12°, 16°/16°/12°, and 20°/20°/12° worts. Fermentations in 16° and 20° worts
decreased yeast vitality measured as acidification power (AP) by a maximum of 10%, lowered yeast proliferation, and increased
fermentation time. Repitching aggravated these effects. The 3rd “back to normal” pitching into 12° wort restored the yeast
AP and reproductive abilities while the extended fermentation time remained. Yeast sedimentation in 16° and 20° worts was
delayed but increased about two times at fermentation end relative to that in 12° wort. Third “back-to-normal” pitching abolished
the delay in sedimentation and reduced its extent, which became nearly equal in all variants. Beer brewed at increased osmolarity
was characterized by increased levels of diacetyl and pentanedione and lower levels of dimethylsulfide and acetaldehyde. Esters
and higher alcohols displayed small variations irrespective of wort osmolarity or repitching. Increased wort osmolarity had
no appreciable effect on the haze of green beer and accelerated beer clarification during maturation. In all variants, chill
haze increased with repitching. 相似文献
112.
Cristiano Nogueira Síria Ribeiro Gabriel C. Costa Guarino R. Colli 《Journal of Biogeography》2011,38(10):1907-1922
Aim To test predictions of the vicariance model, to define basic biogeographical units for Cerrado squamates, and to discuss previous biogeographical hypotheses. Location Cerrado; South American savannas south of the Amazon, extending across central Brazil, with marginal areas in Bolivia and Paraguay and isolated relictual enclaves in adjacent regions. Methods We compiled species occurrence records via field sampling and revision of museum specimens and taxonomic literature. All species were mapped according to georeferenced locality records, and classified as (1) endemic or non‐endemic, (2) typical of plateaus or depressions, and (3) typical of open or forested habitats. We tested predictions of the vicariance model using biotic element analysis, searching for non‐random clusters of species ranges. Spatial congruence of biotic elements was compared with putative areas of endemism revealed by sympatric restricted‐range species. Effects of topographical and vegetational mosaics on distribution patterns were studied according to species composition in biotic elements and areas of endemism. Results We recorded 267 Cerrado squamates, of which 103 (39%) are endemics, including 20 amphisbaenians (61% endemism), 32 lizards (42%) and 51 snakes (32%). Distribution patterns corroborated predictions of the vicariance model, revealing groups of species with significantly clustered ranges. An analysis of endemic species recovered seven biotic elements, corroborating results including non‐endemics. Sympatric restricted‐range taxa delimited 10 putative areas of endemism, largely coincident with core areas of biotic elements detected with endemic taxa. Distribution patterns were associated with major topographical and vegetational divisions of the Cerrado. Endemism prevailed in open, elevated plateaus, whereas faunal interchange, mostly associated with forest habitats, was more common in peripheral depressions. Main conclusions Our results indicate that vicariant speciation has strongly shaped Cerrado squamate diversity, in contrast to earlier studies emphasizing faunal interchange and low endemism in the Cerrado vertebrate fauna. Levels of squamate endemism are higher than in any other Cerrado vertebrate group. The high number of recovered endemics revealed previously undetected areas of evolutionary relevance, indicating that biogeographical patterns in the Cerrado were poorly represented in previous analyses. Although still largely undocumented, effects of vicariant speciation may be prevalent in a large fraction of Cerrado and Neotropical biodiversity. 相似文献
113.
Prof. P. Gabriel Strobl 《Plant Systematics and Evolution》1886,36(9):310-313
Ohne Zusammenfassung 相似文献
114.
Gabriel V. Jaffé 《BMJ (Clinical research ed.)》1961,1(5231):1043-1044
115.
Prof. P. Gabriel Strobl 《Plant Systematics and Evolution》1888,38(2):58-60
Ohne Zusammenfassung 相似文献
116.
Jaeho Kim Woojong Kim Gabriel Jang Da Seul Hyeon Mi Hyun Park Jin Pyo Hong 《Liver Transplantation》2020,10(6)
Highly stretchable self‐powered energy sources are promising options for powering diverse wearable smart electronics. However, commercially existing energy sources are disadvantaged by tensile strain limitations and constrained deformability. Here, 1D thread‐based highly stretchable triboelectric nanogenerators (HS‐TENGs), a crucial step toward overcoming these obstacles, are developed based on a highly stretchable coaxial‐type poly[styrene‐b‐isoprene‐b‐styrene] (SIS) elastomer tube. Carbon conductive ink is injected into the SIS tube as a core 1D electrode that remains almost unaffected even under 250% stretching because of its low Young's modulus. To further facilitate power generation by the HS‐TENG, a composite of barium titanate nanoparticles (BaTiO3 NPs) and polydimethylsiloxane (PDMS) is coated on the initial SIS tube to modulate the dielectric permittivity based on variations in the BaTiO3 NPs volume ratio. The 1D PDMS/BaTiO3 NP composite‐coated SIS and a nylon 6‐coated 2D Ni–Cu conductive fabric are selected as triboelectric bottom and top layers, respectively. Woven HS‐TENGs textiles yield consistent power output under various extreme and harsh conditions, including folded, twisted, and washed states. These experimental findings indicate that the approach may become useful for realizing stretchable multifunctional power sources for various wearable electronics. 相似文献
117.
Samuel Barton James Jenkins Angus Buckling C.-Elisa Schaum Nicholas Smirnoff John A. Raven Gabriel Yvon‐Durocher 《Ecology letters》2020,23(4):722-733
The efficiency of carbon sequestration by the biological pump could decline in the coming decades because respiration tends to increase more with temperature than photosynthesis. Despite these differences in the short‐term temperature sensitivities of photosynthesis and respiration, it remains unknown whether the long‐term impacts of global warming on metabolic rates of phytoplankton can be modulated by evolutionary adaptation. We found that respiration was consistently more temperature dependent than photosynthesis across 18 diverse marine phytoplankton, resulting in universal declines in the rate of carbon fixation with short‐term increases in temperature. Long‐term experimental evolution under high temperature reversed the short‐term stimulation of metabolic rates, resulting in increased rates of carbon fixation. Our findings suggest that thermal adaptation may therefore have an ameliorating impact on the efficiency of phytoplankton as primary mediators of the biological carbon pump. 相似文献
118.
Eben Goodale Hari Sridhar Kathryn E. Sieving Priti Bangal Gabriel J. Colorado Z. Damien R. Farine Eckhard W. Heymann Harrison H. Jones Indrikis Krams Ari E. Martínez Flavia Montao‐Centellas Jenny Muoz Umesh Srinivasan Anne Theo Kartik Shanker 《Biological reviews of the Cambridge Philosophical Society》2020,95(4):889-910
Mixed‐species animal groups (MSGs) are widely acknowledged to increase predator avoidance and foraging efficiency, among other benefits, and thereby increase participants' fitness. Diversity in MSG composition ranges from two to 70 species of very similar or completely different phenotypes. Yet consistency in organization is also observable in that one or a few species usually have disproportionate importance for MSG formation and/or maintenance. We propose a two‐dimensional framework for understanding this diversity and consistency, concentrating on the types of interactions possible between two individuals, usually of different species. One axis represents the similarity of benefit types traded between the individuals, while the second axis expresses asymmetry in the relative amount of benefits/costs accrued. Considering benefit types, one extreme represents the case of single‐species groups wherein all individuals obtain the same supplementary, group‐size‐related benefits, and the other extreme comprises associations of very different, but complementary species (e.g. one partner creates access to food while the other provides vigilance). The relevance of social information and the matching of activities (e.g. speed of movement) are highest for relationships on the supplementary side of this axis, but so is competition; relationships between species will occur at points along this gradient where the benefits outweigh the costs. Considering benefit amounts given or received, extreme asymmetry occurs when one species is exclusively a benefit provider and the other a benefit user. Within this parameter space, some MSG systems are constrained to one kind of interaction, such as shoals of fish of similar species or leader–follower interactions in fish and other taxa. Other MSGs, such as terrestrial bird flocks, can simultaneously include a variety of supplementary and complementary interactions. We review the benefits that species obtain across the diversity of MSG types, and argue that the degree and nature of asymmetry between benefit providers and users should be measured and not just assumed. We then discuss evolutionary shifts in MSG types, focusing on drivers towards similarity in group composition, and selection on benefit providers to enhance the benefits they can receive from other species. Finally, we conclude by considering how individual and collective behaviour in MSGs may influence both the structure and processes of communities. 相似文献
119.
Hubert du Pontavice Didier Gascuel Gabriel Reygondeau Aurore Maureaud William W. L. Cheung 《Global Change Biology》2020,26(3):1306-1318
Sea water temperature affects all biological and ecological processes that ultimately impact ecosystem functioning. In this study, we examine the influence of temperature on global biomass transfers from marine secondary production to fish stocks. By combining fisheries catches in all coastal ocean areas and life‐history traits of exploited marine species, we provide global estimates of two trophic transfer parameters which determine biomass flows in coastal marine food web: the trophic transfer efficiency (TTE) and the biomass residence time (BRT) in the food web. We find that biomass transfers in tropical ecosystems are less efficient and faster than in areas with cooler waters. In contrast, biomass transfers through the food web became faster and more efficient between 1950 and 2010. Using simulated changes in sea water temperature from three Earth system models, we project that the mean TTE in coastal waters would decrease from 7.7% to 7.2% between 2010 and 2100 under the ‘no effective mitigation’ representative concentration pathway (RCP8.5), while BRT between trophic levels 2 and 4 is projected to decrease from 2.7 to 2.3 years on average. Beyond the global trends, we show that the TTEs and BRTs may vary substantially among ecosystem types and that the polar ecosystems may be the most impacted ecosystems. The detected and projected changes in mean TTE and BRT will undermine food web functioning. Our study provides quantitative understanding of temperature effects on trophodynamic of marine ecosystems under climate change. 相似文献
120.
Geraldine Schlapp Maria Noel Meikle Cecilia Silva Gabriel Fernandez-Graa Alejo Menchaca Martina Crispo 《Animal Reproduction》2020,17(4)
The objective was to evaluate the influence of colony aging in a Swiss Webster (SW) outbred stock used as recipients for embryo transfer. In the first study, a retrospective analysis was performed throughout several generations during a 38-month period in 2,398 embryos transferred to 108 SW recipients. A decrease in the percentage of live pups from transferred embryos was found at the end of the period. Impairment occurred due to the incidence of maternal cannibalism that increased from 0% to 67-100% (P<0.05), while pregnancy rate (pregnant/transferred recipients) and number of pups per delivered female were not affected throughout the period (P=NS). A following study was carried out to compare the reproductive performance of SW stock vs. B6D2F1 hybrid females in a 5-year interval. The study was conducted on a total of 893 embryos transferred to 40 females (20 SW and 20 B6D2F1) in Year #1, and 514 embryos transferred to 30 females (15 SW and 15 B6D2F1) in Year #5. No cases of maternal cannibalism were found on Year #1 in any of the strains (0/10 and 0/10). However, an incidence of 44,4% (4/9) was seen on Year #5 for SW, while for B6D2F1 the incidence was 0% (0/12) (P<0.05). Further examination of the uterus showed endometrial cysts and abnormal implantation sites in SW on Year #5 but not in B6D2F1 females. In conclusion, this study reports an impairment of the reproductive performance of an early aged SW outbred stock colony mainly due to the occurrence of maternal cannibalism. This finding has important implications for embryo transfer programs conducted in mouse facilities. 相似文献