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91.
Identifying critical habitat of the endangered vaquita (Phocoena sinus) with regional δ13C and δ15N isoscapes of the Upper Gulf of California,Mexico 下载免费PDF全文
Mónica Y. Rodríguez‐Pérez David Aurioles‐Gamboa Laura Sánchez‐Velásco Seth D. Newsome 《Marine Mammal Science》2018,34(3):790-805
The vaquita (Phocoena sinus) is the world's most endangered cetacean and has experienced a 60% reduction in the size of its population in the past decade. Knowledge of its basic ecology is essential for developing successful management plans to protect and conserve this species. In this study, we identified vaquita foraging areas by creating an isoscape of the Upper Gulf of California (UGC) based on sediment and zooplankton carbon (δ13C) and nitrogen (δ15N) isotope values. Our results confirm that this species is confined to the western region of the UGC, which is characterized by relatively high δ15N values (sediments: 10.2‰ ± 2.0‰, zooplankton: 15.8‰ ± 1.3‰), higher sea surface temperatures (~16°C–25°C), higher concentrations of silt in sediments, and the highest turbidity. In contrast, the eastern region of the UGC had relatively low sediment (7.7‰ ± 2.4‰) and zooplankton (14.6‰ ± 1.0‰) δ15N values, and the highest concentrations of sand in sediments. Our approach is an effective use of marine isoscapes over a small spatial scale (<200 km) to identify the environmental characteristics that define the critical habitat for an extremely endangered marine mammal. 相似文献
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93.
Yossef Alnasser Cusi Ferradas Taryn Clark Maritza Calderon Alejandro Gurbillon Dionicia Gamboa Uri S. McKakpo Isabella A. Quakyi Kwabena M. Bosompem David J. Sullivan Joseph M. Vinetz Robert H. Gilman 《PLoS neglected tropical diseases》2016,10(10)
Plasmodium vivax is the most prevalent cause of human malaria in the world and can lead to severe disease with high potential for relapse. Its genetic and geographic diversities make it challenging to control. P. vivax is understudied and to achieve control of malaria in endemic areas, a rapid, accurate, and simple diagnostic tool is necessary. In this pilot study, we found that a colorimetric system using AuNPs and MSP10 DNA detection in urine can provide fast, easy, and inexpensive identification of P. vivax. The test exhibited promising sensitivity (84%), high specificity (97%), and only mild cross-reactivity with P. falciparum (21%). It is simple to use, with a visible color change that negates the need for a spectrometer, making it suitable for use in austere conditions. Using urine eliminates the need for finger-prick, increasing both the safety profile and patient acceptance of this model. 相似文献
94.
Laura M. Panek George J. Gamboa & Karl E. Espelie 《Ethology : formerly Zeitschrift fur Tierpsychologie》2001,107(1):55-63
The effect of a wasp's age on its cuticular hydrocarbon profile and its tolerance by nestmate and non-nestmate conspecifics was investigated in a laboratory study of newly eclosed wasps ( Polistes fuscatus ) that were isolated from their comb at eclosion. In blind observations, mature females did not discriminate between young nestmates and non-nestmates that were ≤ 48 h-old. However, mature females did discriminate between young nestmates and non-nestmates that were 72 h old. Specifically, mature females were significantly more tolerant of (and significantly more likely to accept) 72 h-old nestmates than 72 h old non-nestmates. The abundance, relative abundance, and colony specificity of cuticular hydrocarbons changed significantly between 24 h-old and 72 h-old wasps. Our behavioral and chemical evidence indicates that wasps begin to develop a colony signature between 2 and 3 d of age. 相似文献
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96.
George J. Gamboa Keith A. Berven Randy A. Schemidt Thomas G. Fishwild Kelli M. Jankens 《Oecologia》1991,86(3):319-324
Summary We investigated kin recognition by larval wood frogs (Rana sylvatica) in blind laboratory experiments using spatial affinity as a recognition assay. Tadpoles reared with full-sibs displayed a significant preference for familiar full-sibs over unfamiliar non-kin, but failed to discriminate between unfamiliar full-sibs and unfamiliar paternal half-sibs. Tadpoles reared in social isolation (with or without maternal egg jelly) from the two-celled embryonic stage displayed a significant preference for unfamiliar full-sibs over unfamiliar non-kin. Tadpoles reared on a meat diet with their full-sibs: 1) exhibited a significant preference for unfamiliar full-sibs fed meat over unfamiliar non-kin fed meat, 2) failed to discriminate between unfamiliar full-sibs fed lettuce and unfamiliar non-kin fed meat, 3) exhibited a significant preference for unfamiliar non-kin fed meat over unfamiliar non-lin fed lettuce, 4) failed to discriminate between unfamiliar full-sibs fed meat and unfamiliar full-sibs fed lettuce, and 5) displayed a significant spatial preference for odors associated with meat (a familiar food) over odors associated with lettuce (an unfamiliar food). Our results, together with those of Cornell et al. (1989), indicate that the recognition cue of larval R. sylvatica has both genetic and environmental (dietary) components. Our findings establish that previous exposure to maternal egg jelly, kin, or conspecifics is not necessary for the development of kin recognition ability in larval R. sylvatica. Our results are more consistent with the self-learning of recognition cues (a form of phenotype matching) than with a recognition mechanism that involves a genetically fixed recognition template. Finally, our results indicate that increasing similarity between the recognition template and perceived cue does not necessarily result in increasing spatial affinity for kin. 相似文献
97.
Gamboa M 《Revista de biología tropical》2010,58(4):1299-1310
Longitudinal distribution of Plecoptera species were examined along the Sierra Nevada National Park in the Andean region of Merida State, Venezuela. PNSN is one of the largest protected areas and consists of two major sub-basins. Quantitative samples were collected in 7 river tributaries along the PNSN from February to May of 2009, and a total of 135 individuals and 4 species of the genus Anacroneuria were collected. Only three rivers (Nuestra Se?ora, La Picón y Corcovada) found the presence of stoneflies, the principal component analysis show that the characterization of habitat, current velocity, dissolved oxygen and the absence of human disturbance sources of influence in a suitable habitat for populations. Stoneflies are endangered or have become extinct throughout much of its range due to human activities. Conservation plans must be implemented urgently, in order to avoid recreational areas and/or economic in vicinity thereof. 相似文献
98.
Ana M. Gamboa Claudia Hidalgo Fernando De León Jorge D. Etchevers Juan F. Gallardo Julio Campo 《Restoration Ecology》2010,18(2):252-260
There is considerable interest in the potential use of soils to sequester carbon for climate change mitigation. As such, there is a need to evaluate the potential for carbon accumulation in tropical regions. We compared the effects of three annual additions of nitrogen and/or phosphorus on soil carbon and nitrogen contents and pools (bulk soil, macro‐, meso‐, and microaggregates) of two regenerating secondary tropical dry forest differing in nutrient status and succession stage (10‐year‐old early‐succession stage and approximately 60‐year‐old late‐succession stage). The selected forest sites were located on a shallow calcareous soil in the Yucatán Peninsula (Mexico). The primary production is limited by nitrogen and phosphorus in early‐succession stage and by phosphorus in late‐succession stage. In each forest site, four independent plots (12 × 12 m2) were established, the treatments being: controls and plots fertilized during three consecutive years with nitrogen, phosphorus, or nitrogen plus phosphorus. In both forests, soil carbon and nitrogen contents were consistently high, with soil carbon:nitrogen ratios generally greater than 10. Results indicate that usually there are no significant increases of soil carbon stock associated to late succession but can be increased to 3.7 Mg·ha?1·yr?1 with adoption of fertilizer practices. The potential soil carbon sequestration in early‐succession forest was estimated to be 2.7 Mg·ha?1·yr?1, and there is no indication that fertilization improves carbon sequestration. In short, results suggest that the soil potential for carbon sequestration in these ecosystems is high and depends on the specific nutrient status of the site. 相似文献
99.
Nitin Udpa Roy Ronen Dan Zhou Junbin Liang Tsering Stobdan Otto Appenzeller Ye Yin Yuanping Du Lixia Guo Rui Cao Yu Wang Xin Jin Chen Huang Wenlong Jia Dandan Cao Guangwu Guo Victoria E Claydon Roger Hainsworth Jorge L Gamboa Mehila Zibenigus Guta Zenebe Jin Xue Siqi Liu Kelly A Frazer Yingrui Li Vineet Bafna Gabriel G Haddad 《Genome biology》2014,15(2):R36
Background
Although it has long been proposed that genetic factors contribute to adaptation to high altitude, such factors remain largely unverified. Recent advances in high-throughput sequencing have made it feasible to analyze genome-wide patterns of genetic variation in human populations. Since traditionally such studies surveyed only a small fraction of the genome, interpretation of the results was limited.Results
We report here the results of the first whole genome resequencing-based analysis identifying genes that likely modulate high altitude adaptation in native Ethiopians residing at 3,500 m above sea level on Bale Plateau or Chennek field in Ethiopia. Using cross-population tests of selection, we identify regions with a significant loss of diversity, indicative of a selective sweep. We focus on a 208 kbp gene-rich region on chromosome 19, which is significant in both of the Ethiopian subpopulations sampled. This region contains eight protein-coding genes and spans 135 SNPs. To elucidate its potential role in hypoxia tolerance, we experimentally tested whether individual genes from the region affect hypoxia tolerance in Drosophila. Three genes significantly impact survival rates in low oxygen: cic, an ortholog of human CIC, Hsl, an ortholog of human LIPE, and Paf-AHα, an ortholog of human PAFAH1B3.Conclusions
Our study reveals evolutionarily conserved genes that modulate hypoxia tolerance. In addition, we show that many of our results would likely be unattainable using data from exome sequencing or microarray studies. This highlights the importance of whole genome sequencing for investigating adaptation by natural selection. 相似文献100.
Gamboa Carlos Javier Obando Ruiz Paula Andrea Cifuentes Kaloush Kamil Elias Linares Juan Pablo Londoño 《The International Journal of Life Cycle Assessment》2021,26(12):2375-2390
The International Journal of Life Cycle Assessment - It is estimated that in Colombia around 25 million tires are disposed of yearly. The management of discarded tires is still a major problem... 相似文献