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31.
Arik Kershenbaum Daniel T. Blumstein Marie A. Roch Çağlar Akçay Gregory Backus Mark A. Bee Kirsten Bohn Yan Cao Gerald Carter Cristiane Cäsar Michael Coen Stacy L. DeRuiter Laurance Doyle Shimon Edelman Ramon Ferrer‐i‐Cancho Todd M. Freeberg Ellen C. Garland Morgan Gustison Heidi E. Harley Chloé Huetz Melissa Hughes Julia Hyland Bruno Amiyaal Ilany Dezhe Z. Jin Michael Johnson Chenghui Ju Jeremy Karnowski Bernard Lohr Marta B. Manser Brenda McCowan Eduardo Mercado III Peter M. Narins Alex Piel Megan Rice Roberta Salmi Kazutoshi Sasahara Laela Sayigh Yu Shiu Charles Taylor Edgar E. Vallejo Sara Waller Veronica Zamora‐Gutierrez 《Biological reviews of the Cambridge Philosophical Society》2016,91(1):13-52
Animal acoustic communication often takes the form of complex sequences, made up of multiple distinct acoustic units. Apart from the well‐known example of birdsong, other animals such as insects, amphibians, and mammals (including bats, rodents, primates, and cetaceans) also generate complex acoustic sequences. Occasionally, such as with birdsong, the adaptive role of these sequences seems clear (e.g. mate attraction and territorial defence). More often however, researchers have only begun to characterise – let alone understand – the significance and meaning of acoustic sequences. Hypotheses abound, but there is little agreement as to how sequences should be defined and analysed. Our review aims to outline suitable methods for testing these hypotheses, and to describe the major limitations to our current and near‐future knowledge on questions of acoustic sequences. This review and prospectus is the result of a collaborative effort between 43 scientists from the fields of animal behaviour, ecology and evolution, signal processing, machine learning, quantitative linguistics, and information theory, who gathered for a 2013 workshop entitled, ‘Analysing vocal sequences in animals’. Our goal is to present not just a review of the state of the art, but to propose a methodological framework that summarises what we suggest are the best practices for research in this field, across taxa and across disciplines. We also provide a tutorial‐style introduction to some of the most promising algorithmic approaches for analysing sequences. We divide our review into three sections: identifying the distinct units of an acoustic sequence, describing the different ways that information can be contained within a sequence, and analysing the structure of that sequence. Each of these sections is further subdivided to address the key questions and approaches in that area. We propose a uniform, systematic, and comprehensive approach to studying sequences, with the goal of clarifying research terms used in different fields, and facilitating collaboration and comparative studies. Allowing greater interdisciplinary collaboration will facilitate the investigation of many important questions in the evolution of communication and sociality. 相似文献
32.
Shane J. Stafslien Stacy Sommer Rajan Bodkhe Robert Pieper Justin Daniels 《Biofouling》2016,32(8):949-968
A series of eight novel siloxane-polyurethane fouling-release (FR) coatings were assessed for their FR performance in both the laboratory and in the field. Laboratory analysis included adhesion assessments of bacteria, microalgae, macroalgal spores, adult barnacles and pseudobarnacles using high-throughput screening techniques, while field evaluations were conducted in accordance with standardized testing methods at three different ocean testing sites over the course of six-months exposure. The data collected were subjected to statistical analysis in order to identify potential correlations. In general, there was good agreement between the laboratory screening assays and the field assessments, with both regimes clearly distinguishing the siloxane-polyurethane compositions comprising monofunctional poly(dimethyl siloxane) (PDMS) (m-PDMS) as possessing superior, broad-spectrum FR properties compared to those prepared with difunctional PDMS (d-PDMS). Of the seven laboratory screening techniques, the Cellulophaga lytica biofilm retraction and reattached barnacle (Amphibalanus amphitrite) adhesion assays were shown to be the most predictive of broad-spectrum field performance. 相似文献
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Winnie Eckardt Tara S. Stoinski Stacy Rosenbaum Rachel Santymire 《Ecology and evolution》2019,9(9):5248-5259
Living in a rapidly changing environment can alter stress physiology at the population level, with negative impacts on health, reproductive rates, and mortality that may ultimately result in species decline. Small, isolated animal populations where genetic diversity is low are at particular risks, such as endangered Virunga mountain gorillas (Gorilla beringei beringei). Along with climate change‐associated environmental shifts that are affecting the entire population, subpopulations of the Virunga gorillas have recently experienced extreme changes in their social environment. As the growing population moves closer to the forest's carrying capacity, the gorillas are coping with rising population density, increased frequencies of interactions between social units, and changing habitat use (e.g., more overlapping home ranges and routine ranging at higher elevations). Using noninvasive monitoring of fecal glucocorticoid metabolites (FGM) on 115 habituated Virunga gorillas, we investigated how social and ecological variation are related to baseline FGM levels, to better understand the adaptive capacity of mountain gorillas and monitor potential physiological indicators of population decline risks. Generalized linear mixed models revealed elevated mean monthly baseline FGM levels in months with higher rainfall and higher mean maximum and minimum temperature, suggesting that Virunga gorillas might be sensitive to predicted warming and rainfall trends involving longer, warmer dry seasons and more concentrated and extreme rainfall occurrences. Exclusive use of smaller home range areas was linked to elevated baseline FGM levels, which may reflect reduced feeding efficiency and increased travel efforts to actively avoid neighboring groups. The potential for additive effects of stress‐inducing factors could have short‐ and long‐term impacts on the reproduction, health, and ultimately survival of the Virunga gorilla population. The ongoing effects of environmental changes and population dynamics must be closely monitored and used to develop effective long‐term conservation strategies that can help address these risk factors. 相似文献
34.
Wickliffe JK Herring SM Hallberg LM Galbert LA Masters OE Ammenheuser MM Xie J Friedberg EC Lloyd RS Abdel-Rahman SZ Ward JB 《Chemico-biological interactions》2007,166(1-3):226-231
1,3-Butadiene (BD) is a well-documented mutagen and carcinogen in rodents and is currently classified as a probable carcinogen in humans. Studies investigating workers exposed to BD indicate that, in some plants, there may be an increased genetic risk, and that polymorphisms in biotransformation and DNA repair proteins may modulate genetic susceptibility. To investigate the role of genetic polymorphisms in microsomal epoxide hydrolase (mEH) or nucleotide excision repair (NER) in contributing to the mutagenicity of BD, we conducted a series of experiments in which mice lacking mEH or NER activity were exposed to BD by inhalation or to the reactive epoxide metabolites of BD (epoxybutene-EB or diepoxybutane-DEB) by i.p. injection. Genetic susceptibility was measured using the Hprt cloning assay. Both deficient strains of mouse were significantly more sensitive to the mutagenic effects of BD and the injected epoxides. These studies provide support for the critical role that mEH plays in the biotransformation of BD, and the role that NER plays in maintaining genomic integrity following exposure to BD. Additional studies are needed to examine the importance of base excision repair (BER) in maintaining genomic integrity, the differential formation of DNA and protein adducts in deficient strains, and the potential for enhanced sensitivity to BD genotoxicity in mice either lacking or deficient in both biotransformation and DNA repair activity. 相似文献
35.
Cholesterol depletion alters detergent-specific solubility profiles of selected tight junction proteins and the phosphorylation of occludin 总被引:3,自引:0,他引:3
Lynch RD Francis SA McCarthy KM Casas E Thiele C Schneeberger EE 《Experimental cell research》2007,313(12):2597-2610
Differential centrifugation of Triton X-100 or CHAPS lysates from control and cholesterol (CH)-depleted MDCK II cells, segregated integral tight junction (TJ) proteins associated with detergent-resistant membranes (DRMs) into two groups. Group A proteins (occludin, claudin-2 and -3) were detected in large, intermediate and small aggregates in both detergents, whereas group B proteins (claudin-1, -4 and -7) were observed in small aggregates in TX-100 and in intermediate and small aggregates in CHAPS. Depletion of CH altered the distribution of group A and B proteins among the three size categories in a detergent-specific manner. In lysates produced with octyl glucoside, a detergent that selectively extracts proteins from DRMs, group A proteins were undetectable in large aggregates and CH depletion did not alter the distribution of either group A or B proteins in intermediate or small aggregates. Neither occludin (group A) nor claudin-1 (group B) was in intimate enough contact with CH to be cross-linked to [(3)H]-photo-cholesterol. However, antibodies to either TJ protein co-immunoprecipitated caveolin-1, a CH-binding protein. Unlike claudins, occludin's presence in TJs and DRMs did not require palmitoylation. Equilibrium density centrifugation on discontinuous OptiPrep gradients revealed detergent-related differences in the densities of TJ-bearing DRMs. There was little or no change in those densities after CH depletion. Removing CH from the plasma membrane increased tyrosine and threonine phosphorylation of occludin, and transepithelial electrical resistance (TER) within 30 min. After 2 h of CH efflux, phospho-occludin levels and TER fell below control values. We conclude that the association of integral TJ proteins with DRMS, pelleted at low speeds, is partially CH-dependent. However, the buoyant density of TJ-associated DRMs is a function of the detergent used and is insensitive to decreases in CH. 相似文献
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Hammond Hammond Stacy Denise Viehmannova Iva Zamecnik Jiri Panis Bart Hlasna Cepkova Petra 《Plant Cell, Tissue and Organ Culture》2019,138(3):559-570
Plant Cell, Tissue and Organ Culture (PCTOC) - Slow-growth is a biotechnological tool for medium-term conservation of plant germplasm under in vitro conditions. In the present study, we assessed... 相似文献
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40.
A phase 1/2 clinical trial of enzyme replacement in fabry disease: pharmacokinetic, substrate clearance, and safety studies 总被引:15,自引:0,他引:15 下载免费PDF全文
Eng CM Banikazemi M Gordon RE Goldman M Phelps R Kim L Gass A Winston J Dikman S Fallon JT Brodie S Stacy CB Mehta D Parsons R Norton K O'Callaghan M Desnick RJ 《American journal of human genetics》2001,68(3):711-722
Fabry disease results from deficient alpha-galactosidase A (alpha-Gal A) activity and the pathologic accumulation of the globotriaosylceramide (GL-3) and related glycosphingolipids, primarily in vascular endothelial lysosomes. Treatment is currently palliative, and affected patients generally die in their 40s or 50s. Preclinical studies of recombinant human alpha-Gal A (r-halphaGalA) infusions in knockout mice demonstrated reduction of GL-3 in tissues and plasma, providing rationale for a phase 1/2 clinical trial. Here, we report a single-center, open-label, dose-ranging study of r-halphaGalA treatment in 15 patients, each of whom received five infusions at one of five dose regimens. Intravenously administered r-halphaGalA was cleared from the circulation in a dose-dependent manner, via both saturable and non-saturable pathways. Rapid and marked reductions in plasma and tissue GL-3 were observed biochemically, histologically, and/or ultrastructurally. Clearance of plasma GL-3 was dose-dependent. In patients with pre- and posttreatment biopsies, mean GL-3 content decreased 84% in liver (n=13), was markedly reduced in kidney in four of five patients, and after five doses was modestly lowered in the endomyocardium of four of seven patients. GL-3 deposits were cleared to near normal or were markedly reduced in the vascular endothelium of liver, skin, heart, and kidney, on the basis of light- and electron-microscopic evaluation. In addition, patients reported less pain, increased ability to sweat, and improved quality-of-life measures. Infusions were well tolerated; four patients experienced mild-to-moderate reactions, suggestive of hypersensitivity, that were managed conservatively. Of 15 patients, 8 (53%) developed IgG antibodies to r-halphaGalA; however, the antibodies were not neutralizing, as indicated by unchanged pharmacokinetic values for infusions 1 and 5. This study provides the basis for a phase 3 trial of enzyme-replacement therapy for Fabry disease. 相似文献