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71.
Stefan Caddy‐Retalic Alan N. Andersen Michael J. Aspinwall Martin F. Breed Margaret Byrne Matthew J. Christmas Ning Dong Bradley J. Evans Damien A. Fordham Greg R. Guerin Ary A. Hoffmann Alice C. Hughes Stephen J. van Leeuwen Francesca A. McInerney Suzanne M. Prober Maurizio Rossetto Paul D. Rymer Dorothy A. Steane Glenda M. Wardle Andrew J. Lowe 《Ecology and evolution》2017,7(13):4607-4619
Transects that traverse substantial climate gradients are important tools for climate change research and allow questions on the extent to which phenotypic variation associates with climate, the link between climate and species distributions, and variation in sensitivity to climate change among biomes to be addressed. However, the potential limitations of individual transect studies have recently been highlighted. Here, we argue that replicating and networking transects, along with the introduction of experimental treatments, addresses these concerns. Transect networks provide cost‐effective and robust insights into ecological and evolutionary adaptation and improve forecasting of ecosystem change. We draw on the experience and research facilitated by the Australian Transect Network to demonstrate our case, with examples, to clarify how population‐ and community‐level studies can be integrated with observations from multiple transects, manipulative experiments, genomics, and ecological modeling to gain novel insights into how species and systems respond to climate change. This integration can provide a spatiotemporal understanding of past and future climate‐induced changes, which will inform effective management actions for promoting biodiversity resilience. 相似文献
72.
The age and growth of the round stingray Urobatis halleri was determined using vertebral sections from animals collected at Seal Beach, California from 2002 to 2005. Annual periodicity was validated from U. halleri injected with oxytetracycline and maintained in captivity over a 2 year period ( n = 7). The coefficients estimated by the von Bertalanffy growth model were the disc width asymptote ( W D∞ ) (286 mm for males and 224 mm for females) and K (0·09 year−1 for males and 0·15 year−1 for females). The age structure of the population consisted of mostly older, mature males and females. Age at maturity was estimated at 3·80 years for females and 3·75 years for males, and the maximum assessed age was 14 years old. Males were more numerous than females throughout the year; however, from May to September, females outnumbered males. The U. halleri age and growth coefficients were comparable to other species in the family Urolophidae. Based on the seasonality and age structure of this population, Seal Beach offers warm-water refuge for U. halleri of reproductive maturity, and the U. halleri at Seal Beach may garner some behavioural thermoregulation benefit. 相似文献
73.
Leukocyte trafficking involves specific recognition between P-selectin and L-selectin and PSGL-1 containing core 2-based O-glycans expressing sialyl Lewis x (SLe(x)) antigen. However, the structural identity of the glycan component(s) displayed by murine neutrophil PSGL-1 that contributes to its P-selectin counter-receptor activity has been uncertain, since these cells express little if any SLe(x) antigen, and because there have been no direct studies to examine murine PSGL-1 glycosylation. To address this uncertainty, we studied PSGL-1 glycosylation in the murine cell line WEHI-3 using metabolic-radiolabeling with (3)H-monosaccharide precursors to detect low-abundance O-glycan structures. We report that PSGL-1 from WEHI-3 cells expresses a di-sialylated core 2 O-glycan containing the SLe(x) antigen. This fucosylated O-glycan is scarce on PSGL-1 and essentially undetectable in total leukocyte glycoproteins from WEHI-3 cells. These results demonstrate that WEHI-3 cells selectively fucosylate PSGL-1 to generate functionally important core 2-based O-glycans containing the SLe(x) antigen. 相似文献
74.
DSP is an important by-product of alumina production via the Bayer process. Under Western Australian processing conditions, the DSP has a sodalite-type structure that can incorporate anions within its framework. This is particularly useful for removal of impurity anions from liquor recycled in the circuit. As a first step to gaining a fundamental understanding of the incorporation process, we have undertaken molecular mechanics calculations to examine the interaction energy between a series of anions and the sodalite framework, as a measure of the affinity of the anions for the sodalite cage. Our calculations predict that the ions have an increased affinity for the cage along the series aluminate, chloride, carbonate, sulfate and hydroxide. These calculations have successfully predicted the trends that we observe from competitive-uptake experiments in our laboratory. 相似文献
75.
Environmental Biology of Fishes - Giant sea bass (Stereolepis gigas, Polyprionidae) are the largest reef-associated teleost in the northeastern Pacific, considered an important predator in... 相似文献
76.
Rex L. Lowe 《Hydrobiologia》2006,561(1):1-11
This paper summarizes the past 34 years of studies of algae by Rex Lowe and his students and collaborators at Bowling Green
State University, Ohio, USA. Sixty-two students have received graduate degrees in this academic program focusing on systematics,
ecology and environmental assessment. The taxonomic/floristic research initially focused on northern Ohio streams but is now
continental to international in scope focusing on the algal flora of the Great Smoky Mountains National Park and on the South
Island of New Zealand. Ecological research has focused on factors that regulate the structure and function of benthic algae.
Variables that have been examined include abiotic resources (nutrients and light), grazers and physical disturbance. Studies
on environmental assessment have focused primarily on the impact of point-source loads of chemicals into water bodies. 相似文献
77.
Lowe DB Bifulco N Bullock WH Claus T Coish P Dai M Dela Cruz FE Dickson D Fan D Hoover-Litty H Li T Ma X Mannelly G Monahan MK Muegge I O'Connor S Rodriguez M Shelekhin T Stolle A Sweet L Wang M Wang Y Zhang C Zhang HJ Zhang M Zhao K Zhao Q Zhu J Zhu L Tsutsumi M 《Bioorganic & medicinal chemistry letters》2006,16(2):297-301
A series of oxazole-substituted indanylacetic acids were prepared which show a spectrum of activity as ligands for PPAR nuclear receptor subtypes. 相似文献
78.
Oxadiazols: a new class of rationally designed anti-human immunodeficiency virus compounds targeting the nuclear localization signal of the viral matrix protein 下载免费PDF全文
Haffar O Dubrovsky L Lowe R Berro R Kashanchi F Godden J Vanpouille C Bajorath J Bukrinsky M 《Journal of virology》2005,79(20):13028-13036
Despite recent progress in anti-human immunodeficiency virus (HIV) therapy, drug toxicity and emergence of drug-resistant isolates during long-term treatment of HIV-infected patients necessitate the search for new targets that can be used to develop novel antiviral agents. One such target is the process of nuclear translocation of the HIV preintegration complex. Previously we described a class of arylene bis(methylketone) compounds that inhibit HIV-1 nuclear import by targeting the nuclear localization signal (NLS) in the matrix protein (MA). Here we report a different class of MA NLS-targeting compounds that was selected using computer-assisted drug design. The leading compound from this group, ITI-367, showed potent anti-HIV activity in cultures of T lymphocytes and macrophages and also inhibited HIV-1 replication in ex vivo cultured lymphoid tissue. The virus carrying inactivating mutations in MA NLS was resistant to ITI-367. Analysis by real-time PCR demonstrated that the compound specifically inhibited nuclear import of viral DNA, measured by two-long terminal repeat circle formation. Evidence of the existence of this mechanism was provided by immunofluorescent microscopy, using fluorescently labeled HIV-1, which demonstrated retention of the viral DNA in the cytoplasm of drug-treated macrophages. Compounds inhibiting HIV-1 nuclear import may be attractive candidates for further development. 相似文献
79.
AB Chang NC Cox J Purcell JM Marchant PJ Lewindon GJ Cleghorn LC Ee GD Withers MK Patrick J Faoagali 《Respiratory research》2005,6(1):1-5
Background and methods
Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.Results
We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.Conclusion
HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely. 相似文献80.
A. W. Procter† E. H. F. Wjong‡ G. C Stratmann S. L. Lowe D. M. Bowen 《Journal of neurochemistry》1989,53(3):698-704
The novel N-methyl-D-aspartate receptor channel ligand (+)-[3H]5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten-5, 10-imine maleate ([3H]MK-801) has been utilized to label this receptor in human brain tissue. Characteristics of [3H]MK-801 binding to well-washed membranes from 17 control subjects and 16 patients with Alzheimer's disease were determined in frontal, parietal, and temporal cerebral cortex and cerebellar cortex. In control tissue the pharmacological specificity of the binding of this substance is entirely consistent with the profile previously reported for rat brain. Binding could be stimulated by the addition of glutamic acid to the incubation medium; addition of glycine produced further enhancement which was not prevented by strychnine. The specificity of the effects of these and other amino acids on the binding was the same as in the rat. In Alzheimer's disease significantly less binding was observed in the frontal cortex under glutamate- and glycine-stimulated conditions. This appears to be associated with a reduced affinity of the site whereas the pharmacological specificity of the site remained unchanged. The effect did not appear to be due to differences in mode of death between Alzheimer's disease and control subjects and is unlikely to be related to factors for which the groups were matched. In contrast, binding was not altered in the absence of added amino acids and presence of glutamate alone. These results imply that in the cerebral cortex the agonist site and a site in the cation channel of the receptor are not selectively altered, but that their coupling to a strychnine-insensitive glycine recognition site is impaired. 相似文献