New directions in island biogeography Santos, Ana M. C; Richard Field; Robert E. Ricklefs
Global ecology and biogeography,
July 2016, Letnik:
25, Številka:
7
Journal Article
Recenzirano
Odprti dostop
AIM: Much of our current understanding of ecological and evolutionary processes comes from island research. With the increasing availability of data on distributions and phylogenetic relationships ...and new analytical approaches to understanding the processes that shape species distributions and interactions, a reâevaluation of this everâinteresting topic is timely. LOCATION: Islands globally. METHODS: We start by arguing that the reasons why island research has achieved so much in the past also apply to the future. We then critically assess the current state of island biogeography, focusing on recent changes in emphasis, including research featured in this special issue of Global Ecology and Biogeography. Finally, we suggest promising themes for the future. We cover both ecological and evolutionary topics, although the greater emphasis on island ecology reflects our own backgrounds and interests. RESULTS: Much ecological theory has been directly or indirectly influenced by research on island biotas. Currently, island biogeography is renascent, with research focusing on, among other things, patterns and processes underlying species interaction networks, species coexistence and the assembly of island communities through ecological and evolutionary time. Continuing island research should provide additional insight into biological invasions and other impacts of human activities, functional diversity and ecosystem functioning, extinction and diversification, species pools and more. Deeper understanding of the similarities and differences between island and mainland systems will aid transferability of island theory to continental regions. MAIN CONCLUSIONS: As research in biogeography and related fields expands in new directions, islands continue to provide opportunities for developing insights, both as natural laboratories for ecology and evolution and because of the exceptions islands often present to the usual ârulesâ of ecology. New data collection initiatives are needed on islands worldâwide and should be directed towards filling gaps in our knowledge of withinâisland distributions of species, as well as the functional traits and phylogenetic relationships of island species.
•Obesity is a major public health problem.•The metabolic dysregulation associated with obesity is remarkably similar to that observed in normal aging.•Substantial evidence suggests the potential of ...obesity to accelerate aging.•Understanding the molecular mechanisms of obesity can provide insights into the aging process.•Lifestyle and pharmacological interventions to manage obesity can also be useful in mitigating the aging process.
The epidemic of obesity is a major challenge for health policymakers due to its far-reaching effects on population health and potentially overwhelming financial burden on healthcare systems. Obesity is associated with an increased risk of developing acute and chronic diseases, including hypertension, stroke, myocardial infarction, cardiovascular disease, diabetes, and cancer. Interestingly, the metabolic dysregulation associated with obesity is similar to that observed in normal aging, and substantial evidence suggests the potential of obesity to accelerate aging. Therefore, understanding the mechanism of fat tissue dysfunction in obesity could provide insights into the processes that contribute to the metabolic dysfunction associated with the aging process.
Here, we review the molecular and cellular mechanisms underlying both obesity and aging, and how obesity and aging can predispose individuals to chronic health complications. The potential of lifestyle and pharmacological interventions to counter obesity and obesity-related pathologies, as well as aging, is also addressed.
Species diversity varies in space and time. Temporal changes in the structure and dynamics of communities can occur at different scales. We investigated the temporal changes of dung beetle ...assemblages in the Amazonian region along seasons, years, and successional stages. We evaluated if assemblage structure changes between temporal scales and whether such changes affect the functional structure of communities. To achieve these goals, we sampled dung beetles using linear transects of baited pitfall traps during the dry and rainy seasons at two natural reserves in the Amazon region, each representing different time scales: one covering successional variations (80, 30, 5, and 1 years of recovery from logging) and the other one encompassing three consecutive years at two successional stages (20 and 10 years from logging). We used Generalized Linear Models to analyze interannual and successional changes in diversity, described assemblage structure with a NMDS, and examined compositional variation by partitioning beta diversity into its nestedness and turnover components. Abundance and richness decrease from the rainy to the dry season and towards earlier successional stages but do not differ between years. Assemblage diversity changes differently in interannual and successional scales. During succession, dung beetle assemblages change drastically, following a nested structure due to the appearance of species and functional groups in later successional stages. In contrast, functional group composition does not show consistent changes between years, displaying a turnover structure. This pattern supports non-deterministic changes in dung beetle assemblage structure along forest succession.
The European Medicines Agency (EMA) and the Current Good Manufacturing Practices (cGMP) in the United States of America, define excipient as the constituents of the pharmaceutical form other than the ...active ingredient, i.e., any component that is intended to furnish pharmacological activity. Although dendrimers do not have a pharmacopoeia monograph and, therefore, cannot be recognized as a pharmaceutical excipient, these nanostructures have received enormous attention from researchers. Due to their unique properties, like the nanoscale uniform size, a high degree of branching, polyvalency, aqueous solubility, internal cavities, and biocompatibility, dendrimers are ideal as active excipients, enhancing the solubility of poorly water-soluble drugs. The fact that the dendrimer's properties are controllable during their synthesis render them promising agents for drug-delivery applications in several pharmaceutical formulations. Additionally, dendrimers can be used for reducing the drug toxicity and for the enhancement of the drug efficacy. This review aims to discuss the properties that turn dendrimers into pharmaceutical excipients and their potential applications in the pharmaceutical and biomedical fields.
Lipids are fundamental building blocks of all cells and play important roles in the pathogenesis of different diseases, including inflammation, autoimmune disease, cancer, and neurodegeneration. The ...lipid composition of different organelles can vary substantially from cell to cell, but increasing evidence demonstrates that lipids become organised specifically in each compartment, and this organisation is essential for regulating cell function. For example, lipid microdomains in the plasma membrane, known as lipid rafts, are platforms for concentrating protein receptors and can influence intra-cellular signalling. Lipid organisation is tightly regulated and can be observed across different model organisms, including bacteria, yeast,
Drosophila,
and
Caenorhabditis elegans,
suggesting that lipid organisation is evolutionarily conserved. In this review, we summarise the importance and function of specific lipid domains in main cellular organelles and discuss recent advances that investigate how these specific and highly regulated structures contribute to diverse biological processes.
The relationship of parasite infections and promotion or protection from allergy and asthma is controversial. Currently, over 1.5 billion people are infected with parasites worldwide, and Ascaris ...lumbricoides is the most frequent soil-transmitted helminth.
To evaluate the biological activity of recombinant A. lumbricoides tropomyosin and investigate IgE cross-reactive responses to tropomyosins by means of microarray methodology for the detection of sensitization to allergen components.
Forty patients 12-75 years of age (25 males) with asthma and/or rhinitis and 10 nonallergic control subjects participated in this study. All patients presented positive skin tests to cockroach extracts and underwent skin prick testing (SPT) with recombinant (r) tropomyosins rPer a 7 from Periplaneta americana and rAsc l 3 from A. lumbricoides, at 10 μg/mL. IgE to cockroach and parasite tropomyosins were measured by chimeric ELISA and ImmunoCAP-ISAC, and total IgE was quantitated by ImmunoCAP. Agreement of results was assessed by κ statistics.
Recombinant A. lumbricoides showed biological activity, inducing positive skin tests in 50% patients with asthma and/or rhinitis. IgE to cockroach and parasite tropomyosins were detected in 55-62% of patients. There was good-to-excellent agreement of results of SPT and IgE measurements by ELISA and ImmunoCAP-ISAC, with κ indices of 0.66-0.95. No skin test reactivity or IgE antibodies to tropomyosins were found in nonallergic individuals.
Our results suggest that IgE responses to tropomyosin from A. lumbricoides may enhance reactivity to homologous allergens upon exposure by inhalation or ingestion, promoting allergic reactions and asthma, or increasing the severity of these clinical conditions.
Does the loss of species through habitat decline follow the same pattern whether the area lost is part of a large or a small habitat? An analysis sheds light on this long-running debate, with its ...implications for conservation strategies.
This Open Access book argues that Southern European countries offer valuable, though historically overlooked, knowledge regarding intimate citizenship. Guided by the fundamental sociological question ...of how change takes place and, concomitantly, how law and social policy adjust to and/or shape the practices and expectations of individuals in the sphere of intimacy, this edited volume explores partnering, parenting and friendship issues from the perspective of lesbian, gay, bisexual, trans and queer people in Italy, Portugal and Spain. Chapters offer a cross-national understanding of the relationship between everyday practices of intimacy amongst LGBTQ people and national legal, political and policy contexts in terms of the recognition of otherwise ‘intimate strangers’. The book contributes to further theoretical and policy debates about citizenship, care and choice, as well as, more broadly, sexuality, welfare, health and justice. This book will be of interest to scholars across Gender and Feminist Studies as well as Citizenship Studies, Law, Policy, and Politics.
This study aimed to assess the influence of grinding on improving the pozzolanic activity of a low porosity diatomite. To that end, three diatomites were produced, with 50% passing particle sizes ...(D50) between 7 and 40 μm, and characterized based on oxide composition, loss on ignition, X-ray diffraction (XRD), particle size distribution, and gas adsorption (specific surface area and porosity). Pozzolanic activity was assessed by electrical conductivity, modified Chapelle test, mechanical testing of lime-based mortar at 7 days, and performance index with Portland cement at 28 days. Additionally, portlandite (CH) consumption by diatomite was monitored up to 91 days of hydration by XRD-Rietveld refinement measurements in CH-diatomite pastes combined with controlled calcination at 900 °C. The grinding procedure ensured effective particle size reduction and produced an ultrafine diatomite (D50 below 10 μm) with low energy consumption. The decline in particle size caused an increase in the specific surface area (SSA) of diatomite without significantly changing pore volume and size. The larger SSA raised the silica solubility and pozzolanic activity of diatomite, altering its classification in terms of pozzolanicity. As evidenced by hydration analysis, the increased reactivity and change in pozzolanicity was due to the rise in CH consumption as the SSA of the diatomite increased.
•Effect of grinding on the pozzolanic activity of diatomite was investigated.•The decline in particle size raised the soluble fraction and pozzolanicity of diatomite.•Grinding was effective in particle size reduction with low energy consumption.•Portlandite content was monitored by XRD-Rietveld refinement in calcium hydroxide-diatomite pastes.•Pozzolanic activity was assessed by physical, chemical and mechanical tests.
Accelerating growth and global expansion of antimicrobial resistance has deepened the need for discovery of novel antimicrobial agents. Antimicrobial peptides have clear advantages over conventional ...antibiotics which include slower emergence of resistance, broad-spectrum antibiofilm activity, and the ability to favourably modulate the host immune response. Broad bacterial susceptibility to antimicrobial peptides offers an additional tool to expand knowledge about the evolution of antimicrobial resistance. Structural and functional limitations, combined with a stricter regulatory environment, have hampered the clinical translation of antimicrobial peptides as potential therapeutic agents. Existing computational and experimental tools attempt to ease the preclinical and clinical development of antimicrobial peptides as novel therapeutics. This Review identifies the benefits, challenges, and opportunities of using antimicrobial peptides against multidrug-resistant pathogens, highlights advances in the deployment of novel promising antimicrobial peptides, and underlines the needs and priorities in designing focused development strategies taking into account the most advanced tools available.
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