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1.
Nature ; 605(7909): 285-290, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35477765

RESUMEN

Comprehensive assessments of species' extinction risks have documented the extinction crisis1 and underpinned strategies for reducing those risks2. Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction3. Because global assessments have been lacking, reptiles have been omitted from conservation-prioritization analyses that encompass other tetrapods4-7. Reptiles are unusually diverse in arid regions, suggesting that they may have different conservation needs6. Here we provide a comprehensive extinction-risk assessment of reptiles and show that at least 1,829 out of 10,196 species (21.1%) are threatened-confirming a previous extrapolation8 and representing 15.6 billion years of phylogenetic diversity. Reptiles are threatened by the same major factors that threaten other tetrapods-agriculture, logging, urban development and invasive species-although the threat posed by climate change remains uncertain. Reptiles inhabiting forests, where these threats are strongest, are more threatened than those in arid habitats, contrary to our prediction. Birds, mammals and amphibians are unexpectedly good surrogates for the conservation of reptiles, although threatened reptiles with the smallest ranges tend to be isolated from other threatened tetrapods. Although some reptiles-including most species of crocodiles and turtles-require urgent, targeted action to prevent extinctions, efforts to protect other tetrapods, such as habitat preservation and control of trade and invasive species, will probably also benefit many reptiles.


Asunto(s)
Conservación de los Recursos Naturales , Extinción Biológica , Reptiles , Caimanes y Cocodrilos , Anfibios , Animales , Biodiversidad , Aves , Mamíferos , Filogenia , Reptiles/clasificación , Medición de Riesgo , Tortugas
3.
Acta Paediatr ; 113(6): 1420-1425, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38363039

RESUMEN

AIM: This study reports the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins subsequently diagnosed with Wilms tumour (WAGR syndrome). METHODS: Two monozygotic female twins were referred at age 2 months with bilateral corneal opacity. A diagnosis of Peters' anomaly associated to aniridia was made in both eyes of both twins. Physical examination and ultrasonography were carried out at 12 months of age to explore the possibility of WAGR-related anomalies, specifically Wilms tumour. DNA were isolated and subjected to whole exome sequencing. RESULTS: Peters' anomaly associated to aniridia in both eyes as well as bilateral Wilms tumour in both children were diagnosed. Exome analyses showed a large heterozygous deletion encompassing 6 648 473 bp in chromosome 11p13, using Integrative Genomics Viewer and AnnotSV software. CONCLUSION: WAGR syndrome is a rare contiguous gene deletion syndrome with a greater risk of developing Wilms tumour associated with Peters' anomaly and congenital aniridia. However, co-occurrence of both anomalies was rarely reported in twins, and never in both eyes of monozygotic twins. Here, we report the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins with WAGR syndrome.


Asunto(s)
Aniridia , Opacidad de la Córnea , Gemelos Monocigóticos , Síndrome WAGR , Tumor de Wilms , Humanos , Femenino , Gemelos Monocigóticos/genética , Síndrome WAGR/genética , Aniridia/genética , Aniridia/complicaciones , Tumor de Wilms/genética , Tumor de Wilms/complicaciones , Lactante , Opacidad de la Córnea/genética , Segmento Anterior del Ojo/anomalías , Segmento Anterior del Ojo/diagnóstico por imagen , Anomalías del Ojo/genética , Anomalías del Ojo/diagnóstico por imagen , Anomalías del Ojo/complicaciones , Enfermedades en Gemelos/genética , Neoplasias Renales/genética , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/complicaciones
4.
Eur J Anaesthesiol ; 41(4): 296-304, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37962353

RESUMEN

BACKGROUND: The potential benefit of videolaryngoscopy use in facilitating tracheal intubation has already been established, however its use was actively encouraged during the COVID-19 pandemic as it was likely to improve intubation success and increase the patient-operator distance. OBJECTIVES: We sought to establish videolaryngoscopy use before and after the early phases of the pandemic, whether institutions had acquired new devices during the COVID-19 pandemic, and whether there had been teaching on the devices acquired. DESIGN: We designed a survey with 27 questions made available via the Joint Information Scientific Committee JISC online survey platform in English, French, Spanish, Chinese, Japanese and Portuguese. This was distributed through 18 anaesthetic and airway management societies. SETTING: The survey was open for 54 to 90 days in various countries. The first responses were logged on the databases on 28 October 2021, with all databases closed on 26 January 2022. Reminders to participate were sent at the discretion of the administering organisations. PARTICIPANTS: All anaesthetists and airway managers who received the study were eligible to participate. MAIN OUTCOME MEASURES: Videolaryngoscopy use before the COVID-19 pandemic and at the time of the survey. RESULTS: We received 4392 responses from 96 countries: 944/4336 (21.7%) were from trainees. Of the 3394 consultants, 70.8% (2402/3394) indicated no change in videolaryngoscopy use, 19.9% (675/3394) increased use and 9.3% (315/3393) reduced use. Among trainees 65.5% (618/943) reported no change in videolaryngoscopy use, 27.7% (261/943) increased use and 6.8% (64/943) reduced use. Overall, videolaryngoscope use increased by 10 absolute percentage points following the pandemic. CONCLUSIONS: Videolaryngoscopy use increased following the early phase of the COVID-19 pandemic but this was less than might have been expected.


Asunto(s)
COVID-19 , Humanos , Laringoscopía , Pandemias , Manejo de la Vía Aérea , Anestesistas
5.
J Evol Biol ; 36(8): 1090-1101, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37322612

RESUMEN

Given the diverse nature of traits involved in territorial defence, they may respond to different selective pressures and then exhibit distinct patterns of evolution. These selective pressures also may cause territorial behaviour to be associated with environmental and morphological variables. Such associations, however, have mostly been studied at the intraspecific level, being phylogenetic analyses of territoriality in a broad taxonomic framework rare in the literature. We used the anuran subfamily Hylinae to test (1) whether two territorial-behaviour traits with different levels of aggression-territorial call and physical combat-are evolutionarily more labile than a morphological trait used in physical combat-the spine-shaped prepollex; (2) whether reproduction in lentic waters and phytotelmata, as well as resource scarcity, might favour the occurrence of territoriality; (3) if physical combat is more important than territorial call for the evolution of body size and sexual size dimorphism and (4) the relationships between territorial-behaviour traits and lineage diversification. We mainly used the literature to build two datasets with different levels of certainty. Territorial-behaviour traits exhibited intermediate levels of phylogenetic signal in Hylinae, whereas the phylogenetic signal for the presence of the spine-shaped prepollex was strong. We found support for the hypothesis that reproduction in lentic water favours the occurrence of territorial behaviour, because the expression of territorial-behaviour traits was more associated with reproduction in lentic than in lotic waters. Territorial-behaviour traits were not correlated with annual precipitation nor with habitat complexity. Body size and sexual size dimorphism were not correlated with the presence of territorial call nor with physical combat. We identified negative correlations between diversification rates and physical combat. Relationships of territorial call and physical combat with diversification rates suggest that these territorial behaviours influence evolutionary processes in different ways.


Asunto(s)
Agresión , Territorialidad , Animales , Filogenia , Ecosistema , Anuros/genética
6.
Microb Ecol ; 86(1): 756-761, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35859070

RESUMEN

Melanophryniscus admirabilis is a small toad, critically endangered with a microendemic distribution in the Atlantic Forest in southern Brazil. The amphibian skin microbiome is considered one of the first lines of defense against pathogenic infections, such as Batrachochytrium dendrobatidis (Bd). The knowledge of skin amphibian microbiomes is important to numerous fields, including species conservation, detection, and quantification of environmental changes and stressors. In the present study, we investigated, for the first time, cultivable bacteria in the skin of wild M. admirabilis, and detected Bd fungus by nested polymerase chain reaction (PCR) technique. Skin swab samples were collected from 15 wild M. admirabilis, and the isolation of bacteria was performed by means of different culture strategies. A total of 62 bacterial isolates being Bacillus (n = 22; 34.48%), Citrobacter (n = 10; 16.13%), and Serratia (n = 12; 19.35%) were more frequently isolated genera. Interestingly, all skin samples tested were Bd negative. Some bacterial genera identified in our study might be acting in a synergic relationship and protecting them against the Bd fungus. In addition, these bacteria may play an essential role in maintaining this species in an environment modulated by anthropic actions. This first report of skin cultivable bacteria from M. admirabilis natural population improves our knowledge of skin amphibian microbiomes, contributing to a better understanding of their ecology and how this species has survived in an environment modulated by anthropic action.


Asunto(s)
Quitridiomicetos , Animales , Bufonidae , Bosques , Bacterias , Piel/microbiología
7.
Curr Microbiol ; 80(11): 339, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37695536

RESUMEN

Melanophryniscus admirabilis is a microendemic and critically endangered toad, known from a single population. This microendemic species inhabits a small fragment of the Atlantic Forest in South Brazil, an area significantly impacted by hydroelectric power plant projects, livestock farming, agricultural activities, biopiracy, and tourism. Given the exclusive and limited population of M. admirabilis, preserving and conserving this species is of utmost importance in Brazil. Research on this species primarily concentrates on its biology, ecology, and ecotoxicology. Currently, there is no knowledge about antimicrobial resistance (AMR) bacteria present in wild M. admirabilis, despite the potential for studying them to provide valuable insights into environmental pollution. To this end, Enterobacteriaceae species (n = 82) obtained from 15 wild M. admirabilis toads were subjected to the standard Kirby-Bauer disk diffusion method to test their AMR. The results showed that Enterobacteriaceae species had the highest antibiotic resistance to IPM (45.1%), CIP (39%), NIT (32.5%), AMP (31.3%), TET (18.3%), and FOX (17%). Of the tested species, 18 (21.9%) species tested were susceptible, 40 (48.8%) were resistant to 1 or 2 different antibiotic classes, and 24 (29.3%) were classified as multidrug-resistant. Overall, our findings suggest that the incidence of AMR in Enterobacteriaceae isolated from wild M. admirabilis is high, indicating environmental stress caused by anthropic pollution in their habit.


Asunto(s)
Agricultura , Enterobacteriaceae , Enterobacteriaceae/genética , Antibacterianos/farmacología , Brasil , Pruebas Antimicrobianas de Difusión por Disco
8.
J Environ Manage ; 326(Pt A): 116640, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36375430

RESUMEN

Sludge dewatering and drying are the main processes related to sludge management in wastewater treatment plants (WWTPs). Sludge disposal is a high-cost activity, and drying the sludge reduces its mass and volume, resulting in savings in storage, handling and transportation. The discoveries regarding the use of solar energy in agricultural studies provided valuable information for using in sewage sludge drying. Some studies have reported that dry sludge has met the EPA Class A requirement for biosolids using only solar energy as an energy source. The proper sludge mixture, manual or mechanical, and the dewatering process can significantly increase the drying rate, reducing drying time and the surface area needed. The environmental conditions and the sludge's type greatly influence the drying system. A solar dryer system may be suitable to dry different types of wastewater sludge. Modeling techniques can predict the behavior of the solar drying system and, thus, save time and money in experimental steps. CFD modeling of the sludge drying system is usually done by adopting specific boundary conditions and solving the Navier Stokes equations for air and sludge. There is no standard methodology for comparing solar dryers and common methodologies, such as system efficiency and thermal efficiency, disregards different dryers in different operational conditions. A SWOT (strengths, weaknesses, opportunities, and threats) analysis indicated that, in general, the chapel-type greenhouse with mixed-mode drying has higher drying rates, resulting in reduced drying time and can be scaled to any size. Thus, this type of dryer emerges as a more economical alternative to commercial solar dryers. Based on a systematic review, this work points the SWOT analysis as a useful tool for selecting solar dryers.


Asunto(s)
Aguas del Alcantarillado , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Desecación/métodos , Luz Solar
9.
J Food Sci Technol ; 60(2): 797-808, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36712212

RESUMEN

The present work used water-soluble protein concentrates from the microalga Tetradesmus obliquus to stabilize sunflower oil emulsions. Microalgal cells were disrupted by sonication, and proteins were separated from the biomass using two methods, isoelectric and solvent precipitations. The protein extracts were concentrated by lyophilization, and the concentrates were used to produce emulsions with three amounts of Tetradesmus obliquus protein concentrate (TobPC) (0.1, 0.5, and 1.0% w/v). Emulsions were homogenized through sonication and characterized for creaming index, optical microscopy, size distribution, ζ-potential, and rheology. Isoelectric precipitation resulted in TobPC with a high protein content (51.46 ± 2.37%) and a better dispersibility profile. Emulsion stability was higher for both the isoelectric TobPC and control systems than for the TobPC solvent. Solvent TobPC does not efficiently stabilize emulsions at low protein concentrations that showed microscopically larger oil droplets and flocculation spots. A high phase separation velocity was observed for solvent TobPC, probably due to the higher hydrodynamic droplet diameters. The increase in TobPC content in the emulsions resulted in more stable emulsions for all samples. Therefore, Tetradesmus obliquus protein concentrates are a potential emulsifying agent.

10.
New Phytol ; 233(1): 534-545, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34537964

RESUMEN

The genus Manihot, with around 120 known species, is native to a wide range of habitats and regions in the tropical and subtropical Americas. Its high species richness and recent diversification only c. 6 million years ago have significantly complicated previous phylogenetic analyses. Several basic elements of Manihot evolutionary history therefore remain unresolved. Here, we conduct a comprehensive phylogenomic analysis of Manihot, focusing on exhaustive sampling of South American taxa. We find that two recently described species from northeast Brazil's Atlantic Forest were the earliest to diverge, strongly suggesting a South American common ancestor of Manihot. Ancestral state reconstruction indicates early Manihot diversification in dry forests, with numerous independent episodes of new habitat colonization, including into savannas and rainforests within South America. We identify the closest wild relatives to Manihot esculenta, including the crop cassava, and we quantify extensive wild introgression into the cassava gene pool from at least five wild species, including Manihot glaziovii, a species used widely in breeding programs. Finally, we show that this wild-to-crop introgression substantially shapes the mutation load in cassava. Our findings provide a detailed case study for neotropical evolutionary history in a diverse and widespread group, and a robust phylogenomic framework for future Manihot and cassava research.


Asunto(s)
Manihot , Evolución Biológica , Pool de Genes , Manihot/genética , Filogenia , América del Sur
11.
J Environ Manage ; 322: 115841, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36049302

RESUMEN

Seagrass meadows, through their large capacity to sequester and store organic carbon in their sediments, contribute to mitigate climatic change. However, these ecosystems have experienced large losses and degradation worldwide due to anthropogenic and natural impacts and they are among the most threatened ecosystems on Earth. When a meadow is impacted, the vegetation is partial- or completely lost, and the sediment is exposed to the atmosphere or water column, resulting in the erosion and remineralisation of the carbon stored. This paper addresses the effects of the construction of coastal infrastructures on sediment properties, organic carbon, and total nitrogen stocks of intertidal seagrass meadows, as well as the size of such stocks in relation to meadow establishing time (recently and old established meadows). Three intertidal seagrass meadows impacted by coastal constructions (with 0% seagrass cover at present) and three adjacent non-impacted old-established meadows (with 100% seagrass cover at present) were studied along with an area of bare sediment and two recent-established seagrass meadows. We observed that the non-impacted areas presented 3-fold higher percentage of mud and 1.5 times higher sedimentary organic carbon stock than impacted areas. Although the impacted area was relatively small (0.05-0.07 ha), coastal infrastructures caused a significant reduction of the sedimentary carbon stock, between 1.1 and 2.2 Mg OC, and a total loss of the carbon sequestration capacity of the impacted meadow. We also found that the organic carbon stock and total nitrogen stock of the recent-established meadow were 30% lower than those of the old-established ones, indicating that OC and TN accumulation within the meadows is a continuous process, which has important consequences for conservation and restoration actions. These results contribute to understanding the spatial variability of blue carbon and nitrogen stocks in coastal systems highly impacted by urban development.


Asunto(s)
Carbono , Ecosistema , Carbono/metabolismo , Secuestro de Carbono , Sedimentos Geológicos/química , Nitrógeno , Agua , Humedales
12.
Crit Rev Food Sci Nutr ; 61(12): 1976-2002, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32462889

RESUMEN

Many countries have been experienced an increase in protein consumption due to the population growth and adoption of protein-rich dietaries. Unfortunately, conventional-based protein agroindustry is associated with environmental impacts that might aggravate as the humankind increase. Thus, it is important to screen for novel protein sources that are environmentally friendly. Microalgae farming is a promising alternative to couple the anthropic emissions with the production of food and feed. Some microalgae show protein contents two times higher than conventional protein sources. The use of whole microalgae biomass as a protein source in food and feed is simple and well-established. Conversely, the production of microalgae protein supplements and isolates requires the development of feasible and robust processes able to fractionate the microalgae biomass in different value-added products. Since most of the proteins are inside the microalgae cells, several techniques of disruption have been proposed to increase the efficiency to extract them. After the disruption of the microalgae cells, the proteins can be extracted, concentrated, isolated or purified allowing the development of different products. This critical review addresses the current state of the production of microalgae proteins for multifarious applications, and possibilities to concatenate the production of proteins and advanced biofuels.


Asunto(s)
Microalgas , Biocombustibles , Biomasa , Alimentos , Proteínas
13.
Bioprocess Biosyst Eng ; 43(6): 1123-1131, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32020445

RESUMEN

Nitrogen (N) sources have been target in microalgae cultivation studies, considering their nutritional impact on growth and high costs. Here, we have evaluated the growth of Scenedesmus obliquus BR003, applying alternative low-cost culture media containing ammonium and urea, or combinations of both N sources. The culture media were applied for indoor and outdoor cultivation, followed by growth analyses and metabolic characterization. The alternative culture media B4 and L4 supported higher biomass production (1.4 g L-1) compared to BG11 (nitrate-based medium). In addition, the lipid percentage was higher for B4 (ammonium-based culture medium), reaching up to 25% DW. High contents of carbohydrates (60%) and proteins (40%) were also obtained in media with ammonium and urea, respectively. Considering the lower costs of alternative fertilizer-based media, using ammonium and/or urea as N sources, and the high lipid content observed, we suggest these media as viable for large-scale production of S. obliquus.


Asunto(s)
Medios de Cultivo/química , Fertilizantes , Scenedesmus/crecimiento & desarrollo
14.
Mol Phylogenet Evol ; 132: 207-218, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30562609

RESUMEN

Intermittent episodes of climate changes, such as those that occurred during the Pleistocene, likely shaped the diversification of the young genus Manihot Mill. (Euphorbiacheae). One of such recently-derived congeners ─ M. carthagenensis ─ exhibits a widely disjunct distribution across dry environments in Eastern South America. Herein, we used molecular data from four nuclear gene regions (sts, ch_metE, g3pdh, and nia-i3) and seven nuclear microsatellite loci for reconstructing the phylogenetic relationships among M. carthagenensis and allied species and exploring likely phylogeographic scenarios that shaped the diversification and the distribution of gene pools of M. carthagenensis across the Caatinga and Chaco. Our data suggest that M. carthagenensis is not a monophyletic clade, as presently circumscribed. Morphological differences, genealogical relationships, and vegetation associations support three well-differentiated lineages, each of which merits the species rank: M. carthagenensis, M. glaziovii, and M. hahnii. Microsatellite data suggest that the newly circumscribed M. carthagenensis consists of at least three distinct gene pools, which are partly structured according to geography. The three gene pools likely evolved in allopatry, but remained interfertile. Population expansions after climate amelioration contributed to structuring hybrid zones. Moreover, we described two new single-copy gene regions (sts and ch_metE) as sources of molecular variation; they can facilitate the fine-scale probing of other parts of the phylogeny across Manihot.


Asunto(s)
Euphorbiaceae/clasificación , Animales , Teorema de Bayes , Evolución Biológica , Haplotipos , Repeticiones de Microsatélite/genética , Sistemas de Lectura Abierta/genética , Filogenia , Filogeografía , Análisis de Secuencia de ADN , América del Sur
15.
J Anim Ecol ; 88(5): 757-767, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30828806

RESUMEN

Foraging modes (ambush vs. active foraging) are often correlated with a suite of morphological, physiological, behavioural and ecological traits known as the "adaptive syndrome" or "syndrome hypothesis." In snakes, an ecological correlate often reported in the literature is that ambush-hunting snakes have a higher relative meal size compared to actively foraging snakes which feed on smaller prey items. This "large meal versus small meal" feeding hypothesis between ambush and active foragers has become a widely accepted paradigm of snake feeding ecology, despite the fact that no rigorous meta-analysis has been conducted to support this generalization. We conducted a phylogenetically explicit meta-analysis, which included ca. 100 species, to test this paradigm of snake feeding ecology. We gathered data on prey size by inducing regurgitation by palpation in free-ranging snakes and by examining the stomach contents of preserved museum specimens. When we found prey, we recorded both snake and prey mass to estimate relative prey mass (prey mass/snake mass). We also reviewed published studies of snake feeding ecology to gather similar information for other species. Ambush and active foragers did not differ in minimum or average meal size but the maximum meal sizes consumed by ambush-foraging snakes were larger than the maximum meal sizes eaten by active foragers. This results in ambush-foraging snakes consuming a significantly wider range of meal sizes, rather than being large meal specialists compared to active foragers. We argue that ambush foragers evolved to be more opportunistic predators because they encounter prey less frequently compared to active foragers. This hypothesis is further supported by the fact that ambush foragers also exhibited marginally wider diet breadths, consuming a broader range of prey types in comparison with active foragers. Our study challenges aspects of the foraging syndrome as it is currently conceived, and our results have important implications for our understanding of how foraging mode has shaped the behaviour and physiology of ambush-foraging snakes.


Asunto(s)
Conducta Predatoria , Serpientes , Animales , Dieta , Ecología , Conducta Alimentaria
16.
J Environ Manage ; 252: 109639, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-31586744

RESUMEN

Microalgae are a potential source of biomass for the production of energy, which is why the amount of research on this topic has increased in recent years. This work describes the state of the art of microalgae production from wastewater treatment plants (WWTP), its potential to generate electricity and the scale in which it is possible. The methodology used was a systematic review of the gasification of microalgae from 49 articles selected. Based on the review, a conceptual scenario for microgeneration in WWTP using as feedstock microalgae for thermal gasification was developed. The most consistent assumptions for a real scale microgeneration are microalgae production in open ponds using domestic sewage as a nutritional medium; the use of the flocculation process in process of harvesting; microalgae to energy through thermal gasification process using a downdraft gasifier. Considering a WWTP with a 3000 m3/d flux capacity, 860 kg/d of dry microalgae biomass might be produced. For which, gasification has a production potential of 0.167 kWh/m3 of treated sewage, but the energy balance is compromised by the drying process. However, when the biogas produced in anaerobic treatment enter in the model, it is possible to add a surplus of electricity of 0.14 kWh/m3 of treated sewage. Finally, a cost estimate is made for the acquisition of drying and gasification-electricity generation systems. For this scenario, the results suggest that the investments may be financially returned after five years, with additional potential for further optimization.


Asunto(s)
Microalgas , Biocombustibles , Biomasa , Aguas del Alcantarillado , Aguas Residuales
17.
Zoolog Sci ; 35(4): 373-381, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30079829

RESUMEN

Feeding specialization is a recurrent issue in the evolution of snakes and is sometimes associated to morphological and/or behavioral adaptations that improve snake performance to exploit a particular food type. Despite its importance for animal fitness, the role of physiological traits has been much less studied than morphological and behavioral traits in the evolution of feeding specialization in snakes. In this context, the energetic cost of post-prandial period is an important physiological factor due to the remarkable effect on the snake energy budget. We collected data on post-prandial metabolic rate (SDA) in five species of pit vipers from the genus Bothrops with different degrees of mammal feeding specialization to test the hypothesis that feeding specialist species have lower energy costs during the digestion of their regular food item when compared to species with a more generalist diet. Our results support this hypothesis and suggest that ontogenetic changes in diet can be accompanied by changes in energy cost of the digestion process.


Asunto(s)
Bothrops/fisiología , Metabolismo Energético/fisiología , Periodo Posprandial/fisiología , Envejecimiento , Animales , Bothrops/clasificación , Especificidad de la Especie
18.
Proc Biol Sci ; 284(1869)2017 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-29263281

RESUMEN

An increase in ecological opportunities, either through changes in the environment or acquisition of new traits, is frequently associated with an increase in species and morphological diversification. However, it is possible that certain ecological settings might prevent lineages from diversifying. Arboreality evolved multiple times in vipers, making them ideal organisms for exploring how potentially new ecological opportunities affect their morphology and speciation regimes. Arboreal snakes are frequently suggested to have a very specialized morphology, and being too large, too small, too heavy, or having short tails might be challenging for them. Using trait-evolution models, we show that arboreal vipers are evolving towards intermediate body sizes, with longer tails and more slender bodies than terrestrial vipers. Arboreality strongly constrains body size and circumference evolution in vipers, while terrestrial lineages are evolving towards a broader range of morphological variants. Trait-dependent diversification models, however, suggest similar speciation rates between microhabitats. Thus, we show that arboreality might constrain morphological evolution but not necessarily affect the rates at which lineages generate new species.


Asunto(s)
Evolución Biológica , Tamaño Corporal , Ecosistema , Viperidae/anatomía & histología , Viperidae/fisiología , Animales , Locomoción , Árboles
19.
J Med Syst ; 41(9): 138, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28762209

RESUMEN

There is a growing interest of using technologies to propose solutions for healthcare issues. One of such issues is the incidence of chronic diseases, which are responsible for a considerable proportion of worldwide mortality. It is possible to prevent the development of such diseases using tools and methods that instruct the population. To achieve this, mobile games provide a powerful environment for teaching different subjects to user, without them actively knowing that they are learning new concepts. Despite the growing interest of using mobile games in healthcare, more specifically by patients with chronic diseases, in the best of our knowledge there are no studies that address the current research being published in the area. To close this gap, we carried out a systematic mapping study to synthesize an overview of the area. Five databases were searched and more than 1200 studies were analyzed and filtered. Among them, 17 met the the inclusion and exclusion criteria defined in this work. The results show that there is still room for research in this area, since the studies focus on a younger audience rather than proposing solutions for all ages. Furthermore, the number of chronic conditions being addressed is still small, obesity and diabetes are prevalent. Besides, the full capacity of game features that foster learning through games are not being employed, the majority of games proposed by the articles encompass less than half of these features.


Asunto(s)
Aplicaciones Móviles , Juegos de Video , Enfermedad Crónica , Diabetes Mellitus , Humanos , Obesidad
20.
Water Sci Technol ; 2017(1): 248-255, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29698239

RESUMEN

Hydrothermal liquefaction is a promising technology to convert wet biomass into bio-oil. However, post-hydrothermal liquefaction wastewater (PHWW) is also produced during the process. This wastewater contains a high concentration of organic compounds, including phenols and N-heterocyclic compounds which are two main inhibitors for biological treatment. Thus, proper treatment is required. In this work, ozone was used to convert phenols and N-heterocyclic compounds with a dosage range of 0-4.64 mg O3/mL PHWW. After ozone treatment, the phenols were fully converted, and acids were produced. However, N-heterocyclic compounds were found to have a low conversion rate (21.7%). The kinetic analysis for the degradation of phenols and N-heterocyclic compounds showed that the substitute played an important role in determining the priority of ozone reactions. The OH moiety in the ring compounds (phenols and pyridinol) may form hydroxyl radical, which lead to an efficient reaction. A substantial improved biodegradability of PHWW was observed after ozone treatment. The ratio of BOD5/COD was increased by about 32.36%, and reached a maximum of 0.41. The improved biodegradability of PHWW was justified by the conversion of phenols and N-heterocyclic compounds.


Asunto(s)
Compuestos Heterocíclicos/química , Ozono , Fenoles/química , Aguas Residuales/química , Biomasa , Reactores Biológicos , Radical Hidroxilo , Cinética , Compuestos Orgánicos , Contaminantes Químicos del Agua/química
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