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1.
Birth Defects Res A Clin Mol Teratol ; 103(3): 203-24, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25761253

RESUMEN

BACKGROUND: Congenital malformations in sea turtles have been considered sporadical. Research carried out in the Mexican Pacific revealed high levels of congenital malformations in the olive ridley, but little or no information is available for other species. We present results from analyses of external congenital malformations in olive ridley, green, and hawskbill sea turtles from Mexican rookeries on the Pacific coast and Gulf of Mexico. METHODS: We examined 150 green and hawksbill nests and 209 olive ridley nests during the 2010 and 2012 nesting seasons, respectively. Olive ridley eggs were transferred to a hatchery and incubated in styrofoam boxes. Nests from the other two species were left in situ. Number of eggs, live and dead hatchlings, and eggs with or without embryonic development were registered. Malformation frequency was evaluated with indices of prevalence and severity. RESULTS: Mortality levels, prevalence and severity were higher in olive ridley than in hawksbill and green sea turtles. Sixty-three types of congenital malformations were observed in embryos, and dead or live hatchlings. Of these, 38 are new reports; 35 for wild sea turtles, three for vertebrates. Thirty-one types were found in hawksbill, 23 in green, and 59 in olive ridley. The head region showed a higher number of malformation types. Malformation levels in the olive ridley were higher than previously reported. CONCLUSION: Olive ridleys seem more prone to the occurrence of congenital malformations than the other two species. Whether the observed malformation levels are normal or represent a health problem cannot be currently ascertained without long-term assessments.


Asunto(s)
Anomalías Congénitas , Embrión no Mamífero/anomalías , Tortugas/anomalías , Animales , Femenino , Golfo de México , Masculino
2.
AoB Plants ; 16(1): plad089, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38213511

RESUMEN

Hybridization is commonly reported in angiosperms, generally based on morphology, and in few cases confirmed by molecular markers. Fuchsia has a long tradition of ornamental cultivars with different hybrids produced by artificial crosses, so natural hybridization between sympatric Fuchsia species could be common. Natural hybridization between F. microphylla and F. thymifolia was tested using six newly developed microsatellites for F. microphylla in addition to other molecular markers with codominant and maternal inheritance. Geometric morphometrics of leaves and floral structures were also used to identify putative hybrids. Hybrids showed a different degree of genetic admixture between both parental species. Chloroplast DNA (cpDNA) sequences indicated that hybridization occurs in both directions, in fact, some of the hybrids showed new haplotypes for cpDNA and ITS (internal transcriber spacer of nuclear ribosomal RNA genes) sequences. The morphology of hybrid individuals varied between the two parental species, but they could be better identified by their leaves and floral tubes. Our study is the first to confirm the hybridization in natural populations of Fuchsia species and suggests that hybridization has probably occurred repeatedly throughout the entire distribution of the species. Phylogeographic analysis of both species will be essential to understanding the impact of hybridization throughout their complete distribution.

3.
Sci Rep ; 13(1): 1542, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36707700

RESUMEN

The state of Campeche, Mexico, harbors one of the largest green turtle (Chelonia mydas) rookeries of the Wider Caribbean Region. Since the 1970s, harvesting of this population was common practice, but it has since ceased, and the population is rebounding as a consequence. In this rookery, during the past 37 years (1984-2020), the positive relationship between the annual number of nesting females and the number of hatchlings they produce has revealed a long-term population signal that we postulate could be related to environmental factors. To investigate this relationship more deeply, we adopt a stock-recruitment (SR) approach, which is commonly used in fisheries. Regression analysis methods for the SR relationship, including a dynamic version of the model that incorporates the effect of sea surface temperature, show that the number of recruits produced and the number of hatchlings per unit nester were significantly and inversely correlated with a 26-year cycle of the Atlantic Multidecadal Oscillation (AMO) with a three year lag. A possible explanation for this finding is that environmental conditions during warming periods of the 26-year AMO cycle may negatively affect hatchling production by altering the nest moisture content during the incubation period, and increasing embryonic mortality, while the annual female abundance at nesting beaches may decrease due to trophic effects. The time series of abundance corresponding to other population units of green turtles as well as other species of sea turtles in the Gulf of Mexico present a similar behavior to that evaluated here, suggesting a basin-wide environmental effect.


Asunto(s)
Tortugas , Animales , Femenino , Temperatura , Clima , Ambiente , Cambio Climático , Comportamiento de Nidificación
4.
Heliyon ; 9(11): e22096, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38034602

RESUMEN

Objectives: Add-on testing refers to the process that occurs in clinical laboratories when clinicians request that additional tests be performed on a previously analysed specimen. This is a common but inefficient procedure, highly time-consuming, especially at core laboratories and could be optimised by automating these procedures. The aims of this study are: 1) To describe patterns of add-on testing at a core laboratory at a tertiary hospital, 2) To evaluate turnaround time (TAT) before and after automation of the pre-, post- and analytical phases. Methods: Retrospective, observational study conducted at the biochemistry area of a core laboratory of all add-on orders received in two different months (pre-automation and post-automation). Results: A total of 2464 add-on orders were analysed, representing around 5 % of total requests. Most orders were for either one (>50 %) or two (≈20 %) tests. Most orders were received during the week (from Monday to Friday), particularly during the morning shift (>50 %). More than 50 % of requests were made by the Emergency Department. The two most common add-on parameters were C-reactive protein and N-terminal pro-brain natriuretic peptide. After automation, the median TAT decreased by 42.3 % (from 52 to 22 min). The largest decreases in TAT were observed for routine samples (58.89 %) and fully automated analyses (56.86 %). Conclusions: Automation of our core laboratory substantially reduced turnaround time for add-on testing, indicating an increase in efficiency. Automation eliminated several manual steps in the process, leading to a mean reduction of 15 work hours per day (more than 2 full-time equivalents).

5.
Animals (Basel) ; 12(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36496800

RESUMEN

Long-term monitoring programs of species at risk are efficacious tools to assess population changes, evaluate conservation strategies, and improve management practices to ensure populations reach levels at which they can fulfill their ecological roles. For sea turtles, annual nesting beach surveys are the most accessible method to estimating the population abundance and reproductive output, especially when these are done in primary nesting sites. However, little data exist on the long-term assessment of these parameters. Here, we present the trends of the nest abundance, female size, hatching, and emergence success of hawksbill (Eretmochelys imbricata) and green (Chelonia mydas) turtles at key nesting beaches in the southern Gulf of Mexico over 31 years (from 1990 to 2021). The nest abundance showed an increasing trend in both species as a result of the sustained protection and conservation effort, but there was no significant temporal trend in the annual female size, clutch size, hatching, and emergence success. However, these indicators showed decreasing mean values over the last decade and should be closely monitored. We suggest these decreases link to the combined effects of ocean warming and anthropogenic pressures affecting the sea turtle foraging grounds. Aside from protecting key nesting sites, protecting and restoring crucial foraging habitats should be an immediate priority requiring international cooperation.

6.
Trends Ecol Evol ; 34(5): 459-473, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30879872

RESUMEN

There have been efforts around the globe to track individuals of many marine species and assess their movements and distribution, with the putative goal of supporting their conservation and management. Determining whether, and how, tracking data have been successfully applied to address real-world conservation issues is, however, difficult. Here, we compile a broad range of case studies from diverse marine taxa to show how tracking data have helped inform conservation policy and management, including reductions in fisheries bycatch and vessel strikes, and the design and administration of marine protected areas and important habitats. Using these examples, we highlight pathways through which the past and future investment in collecting animal tracking data might be better used to achieve tangible conservation benefits.


Asunto(s)
Conservación de los Recursos Naturales , Explotaciones Pesqueras , Animales , Ecosistema
8.
PLoS One ; 13(10): e0205178, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30335793

RESUMEN

Palm leaves represent one of the most important non-timber forest products in tropical and subtropical regions. Brahea aculeata is an endemic palm of northwest Mexico, whose leaves are intensively exploited for roof thatch and handcrafts. As part of a long-term defoliation experiment, we evaluated the effects of different leaf harvest on foliar and reproductive traits of adults and attributes of their progeny. We conducted a six-year manipulative experiment and applied three harvesting treatments to adults: high harvest, low harvest and no harvest (control). We recorded leaf production and size, flower and fruit production, seed germination and seedling growth. We also explored trade-offs among foliar and reproductive traits. Harvested palms exhibited drastically reduced reproductive activity, producing fewer flowers and fruits (up to 80 and 90% fewer than unharvested palms). However, individuals in both harvest treatments had larger leaves and increased leaf production rates, compared to control palms. For harvested palms, we registered first a slight increase in leaf traits and a decline in reproductive attributes. These traits showed a gradual reduction and for six period attained very low proportional values compared to control palms (~0.10), however individuals in the harvested treatments maintained the greatest leaf lengths and leaf production rates. Seed germination and seedling growth rates of progeny from harvested palms were significantly lower than control palms, with seeds from the high harvest treatment having the lowest seed production and germination rates. Relationships among leaf (size/production) and reproductive traits (flower/fruit production) were positive during the fourth year, but showed negative relationships for the fifth year suggesting a trade-off between reproduction and growth functions. Leaf harvesting in B. aculeata seems to alter patterns of resource allocation away from reproduction as reflected in a decrease in the probability of reproduction, seed number, germination, and vigor, causing a strong decrease in the reproductive success of this species. Results showed that the consequences of long-term leaf harvest not only affect harvested individuals, but also the fitness and vigor of progeny. This type of long-term studies is essential to understand the population dynamics of non-timber forest products and helps inform sustainable harvesting programs considering intensity, frequencies and periods for recovery from defoliation. Also results may help to explain how intensive and non-planned management schemes may negatively affect vital rates and long-term dynamics of populations from non-timber forest products and other components of the ecosystem.


Asunto(s)
Arecaceae , Agricultura Forestal , Bosques , Hojas de la Planta , Arecaceae/anatomía & histología , Arecaceae/crecimiento & desarrollo , Conservación de los Recursos Naturales , Flores , Agricultura Forestal/métodos , Frutas , Germinación , México , Hojas de la Planta/anatomía & histología , Hojas de la Planta/crecimiento & desarrollo , Reproducción , Plantones/crecimiento & desarrollo , Semillas
9.
Ecol Evol ; 7(12): 4129-4134, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28649325

RESUMEN

The widespread presence of incomplete dichogamy (i.e., partial separation in time between male and female phases) in flowering plants is a long-standing question in floral evolution. In this study, we proposed four scenarios in which depending on the particular combination of pollen limitation and inbreeding depression, the presence of complete dichogamy, incomplete dichogamy, or adichogamy may be favored. Moreover, we evaluated the role of pollen limitation and inbreeding depression in a natural population of Salvia elegans to test the validity of our predicted scenarios. Our results indicate that S. elegans is partially protandrous as pollen viability and stigma receptivity overlap in the last days of life of the flower. Furthermore, through pollination treatments, we found no evidence of pollen limitation or inbreeding depression in any of the evaluated fitness components. As expected by one of the proposed scenarios, incomplete dichogamy seems to be favored in plants with absence of inbreeding depression and pollen limitation as a way to diminish interference between male and female functions.

10.
Materials (Basel) ; 8(9): 5974-5985, 2015 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-28793545

RESUMEN

Ethane 1,2-diamineborane (EDAB) is an alkyl-containing amine-borane adduct with improved hydrogen desorption properties as compared to ammonia borane. In this work, it is reported the high temperature thermolytic decomposition of EDAB. Thermolysis of EDAB has been investigated by concomitant thermogravimetry-differential thermal analysis-mass spectrometry experiments. EDAB shows up to four H2 desorption events below 1000 °C. Small fractions of CH4, C2H4 and CO/CO2 are also observed at moderate-high temperatures. The solid-state thermolysis product has been characterized by means of different structural and chemical methods, such as X-ray diffraction, Raman spectroscopy, Scanning electron microscopy, Elemental analysis, and X-ray photoelectron spectroscopy (XPS). The obtained results indicate the formation of a ternary borocarbonitride compound with a poorly-crystalline graphitic-like structure. By contrast, XPS measurements show that the surface is rich in carbon and nitrogen oxides, which is quite different to the bulk of the material.

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