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101.
Scales H Balmford A Manica A 《Proceedings. Biological sciences / The Royal Society》2007,274(1612):989-994
The live reef fish trade (LRFT) is one of the greatest but least-quantified sources of fishing pressure for several species of large coral reef fish across the Indo-Pacific. For the first time we quantify the localized impact of the LRFT. We collected data from three LRFT traders in northern Borneo, which yielded information on daily fishing effort and the species and mass of all fishes sold every day by individual fishers or vessels over 2, 3 and 8 years. Total monthly catch and relative abundance (catch-per-unit-effort) declined significantly in several species, including the most valuable species the Napoleon wrasse (Cheilinus undulatus, estimated changes of -98 and -78% over 8 years in catch and relative abundance, respectively) and lower-value bluelined groupers (Plectropomus oligocanthus: -99 and -81%) and Epinephelus groupers (-89 and -32%). These severe declines were rapid, species-specific and occurred in the first 2-4 years of the dataset and are, we believe, directly attributable to the LRFT. This has crucial implications for future data collection and monitoring if population collapses in other parts of the LRFT and similar wildlife trades are to be successfully detected. 相似文献
102.
James D. J. Gilbert Andrea Manica 《Evolution; international journal of organic evolution》2015,69(5):1255-1270
Which sex should care for offspring is a fundamental question in evolution. Invertebrates, and insects in particular, show some of the most diverse kinds of parental care of all animals, but to date there has been no broad comparative study of the evolution of parental care in this group. Here, we test existing hypotheses of insect parental care evolution using a literature‐compiled phylogeny of over 2000 species. To address substantial uncertainty in the insect phylogeny, we use a brute force approach based on multiple random resolutions of uncertain nodes. The main transitions were between no care (the probable ancestral state) and female care. Male care evolved exclusively from no care, supporting models where mating opportunity costs for caring males are reduced—for example, by caring for multiple broods—but rejecting the “enhanced fecundity” hypothesis that male care is favored because it allows females to avoid care costs. Biparental care largely arose by males joining caring females, and was more labile in Holometabola than in Hemimetabola. Insect care evolution most closely resembled amphibian care in general trajectory. Integrating these findings with the wealth of life history and ecological data in insects will allow testing of a rich vein of existing hypotheses. 相似文献
103.
Birgit Märtens Salim Manoharadas David Hasenöhrl Andrea Manica Udo Bläsi 《EMBO reports》2013,14(6):527-533
We report the first example of antisense RNA regulation in a hyperthermophilic archaeon. In Sulfolobus solfataricus, the transposon‐derived paralogous RNAs, RNA‐2571–4, show extended complementarity to the 3′ UTR of the 1183 mRNA, encoding a putative phosphate transporter. Phosphate limitation results in decreased RNA‐2571 and increased 1183 mRNA levels. Correspondingly, the 1183 mRNA is faster degraded in vitro upon duplex formation with RNA‐2571. Insertion of the 1183 3′ UTR downstream of the lacS gene results in strongly reduced lacS mRNA levels in transformed cells, indicating that antisense regulation can function in trans. 相似文献
104.
Musa A Khalil E Hailu A Olobo J Balasegaram M Omollo R Edwards T Rashid J Mbui J Musa B Abuzaid AA Ahmed O Fadlalla A El-Hassan A Mueller M Mucee G Njoroge S Manduku V Mutuma G Apadet L Lodenyo H Mutea D Kirigi G Yifru S Mengistu G Hurissa Z Hailu W Weldegebreal T Tafes H Mekonnen Y Makonnen E Ndegwa S Sagaki P Kimutai R Kesusu J Owiti R Ellis S Wasunna M 《PLoS neglected tropical diseases》2012,6(6):e1674
Background
Alternative treatments for visceral leishmaniasis (VL) are required in East Africa. Paromomycin sulphate (PM) has been shown to be efficacious for VL treatment in India.Methods
A multi-centre randomized-controlled trial (RCT) to compare efficacy and safety of PM (20 mg/kg/day for 21 days) and PM plus sodium stibogluconate (SSG) combination (PM, 15 mg/kg/day and SSG, 20 mg/kg/day for 17 days) with SSG (20 mg/kg/day for 30 days) for treatment of VL in East Africa. Patients aged 4–60 years with parasitologically confirmed VL were enrolled, excluding patients with contraindications. Primary and secondary efficacy outcomes were parasite clearance at 6-months follow-up and end of treatment, respectively. Safety was assessed mainly using adverse event (AE) data.Findings
The PM versus SSG comparison enrolled 205 patients per arm with primary efficacy data available for 198 and 200 patients respectively. The SSG & PM versus SSG comparison enrolled 381 and 386 patients per arm respectively, with primary efficacy data available for 359 patients per arm. In Intention-to-Treat complete-case analyses, the efficacy of PM was significantly lower than SSG (84.3% versus 94.1%, difference = 9.7%, 95% confidence interval, CI: 3.6 to 15.7%, p = 0.002). The efficacy of SSG & PM was comparable to SSG (91.4% versus 93.9%, difference = 2.5%, 95% CI: −1.3 to 6.3%, p = 0.198). End of treatment efficacy results were very similar. There were no apparent differences in the safety profile of the three treatment regimens.Conclusion
The 17 day SSG & PM combination treatment had a good safety profile and was similar in efficacy to the standard 30 day SSG treatment, suggesting suitability for VL treatment in East Africa.Clinical Trials Registration
www.clinicaltrials.gov NCT00255567相似文献105.
Given their large movement capacities, migratory birds have in principle a wide range of possible geographical locations for their breeding and non‐breeding destinations, yet each species migrates between consistent breeding and non‐breeding ranges. In this study, we use a macroecological approach to search for the general factors explaining the location of the seasonal ranges of migratory bird species across the globe. We develop a null model to test the hypotheses that access to resources, geographical distance, tracking of temperature, and habitat conditions (separately as well as considered together) have a major influence in the location of species’ migratory destinations, once each species’ geographical constraints are taken into account. Our results provide evidence for a trade‐off between costs associated with distance travelled and gains in terms of better access to resources. We also provide strong support to the hypotheses that all factors tested, with the exception of habitat, have a strong and additive effect on the global geography of bird migration. Indeed, our results indicate that species’ contemporary migratory destinations (i.e. the combination of their breeding and non‐breeding ranges) are such that they allow species to track a temperature regime throughout the year, to escape local competition and reach areas with better access to resources, and to minimise the spatial distance travelled, within the limitations imposed by the geographical location of each species. Our study thus sheds light on the mechanisms underpinning bird migration and provides a strong basis for predicting how migratory species will respond to future change. 相似文献
106.
Börger L Franconi N De Michele G Gantz A Meschi F Manica A Lovari S Coulson T 《The Journal of animal ecology》2006,75(6):1393-1405
1. Although the home range is a fundamental ecological concept, there is considerable debate over how it is best measured. There is a substantial literature concerning the precision and accuracy of all commonly used home range estimation methods; however, there has been considerably less work concerning how estimates vary with sampling regime, and how this affects statistical inferences. 2. We propose a new procedure, based on a variance components analysis using generalized mixed effects models to examine how estimates vary with sampling regime. 3. To demonstrate the method we analyse data from one study of 32 individually marked roe deer and another study of 21 individually marked kestrels. We subsampled these data to simulate increasingly less intense sampling regimes, and compared the performance of two kernel density estimation (KDE) methods, of the minimum convex polygon (MCP) and of the bivariate ellipse methods. 4. Variation between individuals and study areas contributed most to the total variance in home range size. Contrary to recent concerns over reliability, both KDE methods were remarkably efficient, robust and unbiased: 10 fixes per month, if collected over a standardized number of days, were sufficient for accurate estimates of home range size. However, the commonly used 95% isopleth should be avoided; we recommend using isopleths between 90 and 50%. 5. Using the same number of fixes does not guarantee unbiased home range estimates: statistical inferences differ with the number of days sampled, even if using KDE methods. 6. The MCP method was highly inefficient and results were subject to considerable and unpredictable biases. The bivariate ellipse was not the most reliable method at low sample sizes. 7. We conclude that effort should be directed at marking more individuals monitored over long periods at the expense of the sampling rate per individual. Statistical results are reliable only if the whole sampling regime is standardized. We derive practical guidelines for field studies and data analysis. 相似文献
107.
Land‐use strategies to balance livestock production,biodiversity conservation and carbon storage in Yucatán,Mexico 下载免费PDF全文
David R Williams Fredy Alvarado Rhys E Green Andrea Manica Ben Phalan Andrew Balmford 《Global Change Biology》2017,23(12):5260-5272
Balancing the production of food, particularly meat, with preserving biodiversity and maintaining ecosystem services is a major societal challenge. Research into the contrasting strategies of land sparing and land sharing has suggested that land sparing—combining high‐yield agriculture with the protection or restoration of natural habitats on nonfarmed land—will have lower environmental impacts than other strategies. Ecosystems with long histories of habitat disturbance, however, could be resilient to low‐yield agriculture and thus fare better under land sharing. Using a wider suite of species (birds, dung beetles and trees) and a wider range of livestock‐production systems than previous studies, we investigated the probable impacts of different land‐use strategies on biodiversity and aboveground carbon stocks in the Yucatán Peninsula, Mexico—a region with a long history of habitat disturbance. By modelling the production of multiple products from interdependent land uses, we found that land sparing would allow larger estimated populations of most species and larger carbon stocks to persist than would land sharing or any intermediate strategy. This result held across all agricultural production targets despite the history of disturbance and despite species richness in low‐ and medium‐yielding agriculture being not much lower than that in natural habitats. This highlights the importance, in evaluating the biodiversity impacts of land use, of measuring population densities of individual species, rather than simple species richness. The benefits of land sparing for both biodiversity and carbon storage suggest that safeguarding natural habitats for biodiversity protection and carbon storage alongside promoting areas of high‐yield cattle production would be desirable. However, delivering such landscapes will probably require the explicit linkage of livestock yield increases with habitat protection or restoration, as well as a deeper understanding of the long‐term sustainability of yields, and research into how other societal outcomes vary across land‐use strategies. 相似文献
108.
Hajar Owji Navid Nezafat Manica Negahdaripour Ali Hajiebrahimi Younes Ghasemi 《European journal of cell biology》2018,97(6):422-441
Signal peptides (SP) are short peptides located in the N-terminal of proteins, carrying information for protein secretion. They are ubiquitous to all prokaryotes and eukaryotes. SPs have been of special interest in several scientific and industrial fields, including recombinant protein production, disease diagnosis, immunization, and laboratory techniques. Recently, the role of SPs in recombinant protein production has gained too much attention. Herein, several studies have been reviewed to elucidate the precise structure and function of SPs, particularly the optimized ones for recombinant protein production. However, some features of SPs still have remained obscure. In this review, some approaches concerning elucidation and optimization of SPs are discussed, and pragmatic conclusions and suggestions for future studies are also proposed. Moreover, a summary of secretory pathways, evolutionary changes, functions, applications, and different types of SPs is mentioned. At last, current limitations and prospects are discussed. 相似文献
109.
de Nigro Thanise Pitelli Manica Graciele Cristiane More de Souza Susan Webber Jesus Carlos Henrique Alves Bottini Rúbia Camila Ronqui Missina Juliana Morais Valdameri Glaucio Nunes Giovana Gioppo da Cunha Joice Maria Picheth Geraldo Rego Fabiane Gomes de Moraes 《Biometals》2022,35(5):903-919
BioMetals - Diabetes mellitus, a complex and heterogeneous disease associated with hyperglycemia, is a leading cause of mortality and reduces life expectancy. Vanadium complexes have been studied... 相似文献
110.
Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world’s birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes) where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective. 相似文献