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1.
J Intellect Disabil ; : 17446295241228044, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238888

RESUMEN

Internationally, there is a wide variety of roles and expectations for intellectual disabilities nurses, and the range of nursing interventions they undertake in this field has not been clearly identified. In this paper we report the impacts of intellectual nursing interventions from an online survey of intellectual disability nurses. An online survey, using voluntary response sampling was used to collect case study examples from 230 participants from seven countries. We identified 13 themes of the impacts, and 23 broad groups of case examples of intellectual disability nursing interventions with, pregnant women, children, adults, older adults, and people at the end of life. Awareness of the roles of intellectual disability nurses and their importance in addressing health inequalities and facilitating the use of mainstream services for people with intellectual disabilities will enable improved healthcare experience and healthcare outcomes for people with intellectual disabilities.

2.
J Intellect Disabil ; : 17446295231220432, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38081159

RESUMEN

The objective of this scoping review was to summarise evidence on the contribution of intellectual disabilities nurses to improve the health and well-being of children, adults and older people with intellectual disability, now and for the future. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (for Scoping Reviews) (PRISMA-ScR) process and Joanna Briggs Institute (JBI) guidance was used. We included 54 publications. We identified 154 interventions undertaken by intellectual disability nurses. We categorised the intellectual disability nursing interventions into three themes: effectuating nursing procedures, enhancing impact of services, and enhancing quality of life.Findings point to high quality research being essential in determining the impact and effectiveness of intellectual disability nursing interventions across the lifespan. We recommend that a searchable online compendium of intellectual disability nurse interventions be established and regularly updated. This will provide opportunities to engage more effectively in evidence-based practice.

3.
J Intellect Disabil ; : 17446295231213434, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37956695

RESUMEN

The objective was to identify ID nursing interventions and their impact on the health and healthcare of people with IDs. Data was collected using an online survey questionnaire from a voluntary response and snowball sample of 230 participants. Thematic, descriptive statistical, and inferential statistical analyses were undertaken. We identified 878 interventions that could be undertaken by ID nurses from 7 countries. We categorised the interventions into five themes: effectuating nursing procedures, enhancing impact of ID services, enhancing impact of mainstream services, enhancing quality of life, and enhancing ID nursing practice. Findings demonstrate that ID nurses play important roles in improving the health and healthcare experiences of people with IDs.

4.
Disabil Rehabil ; : 1-25, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37982380

RESUMEN

PURPOSE: This review aimed to characterise and map: (1) what type of evidence and what dominant study characteristics are available regarding acquired brain injury (ABI) survivors' experience of occupation and activity in hospital? (2) How are occupation and activity conceptualised in the literature? (3) How are ABI survivors experiencing occupation and activity while in hospital? (4) What factors create barriers or opportunities for engagement in occupations or activity in hospital? (5) Are there any knowledge gaps identified? MATERIALS AND METHODS: A scoping review was conducted examining literature published between 2017 and 2022. Relevant studies were systematically retrieved from electronic databases. RESULTS: Thirty-four publications were included. There were more quantitative studies (n = 18). Much of the research has been conducted outside of the UK. The populations studied were principally stroke (n = 22). The concept of activity rather than occupation predominates. Patients spend their time alone and inactive. Structural and contextual barriers for engaging in activity are identified. Qualitative study designs exclude ABI survivors with communication or cognitive impairment. CONCLUSIONS: There is a paucity of research with ABI survivors in hospitals in the UK. Alternative methodological approaches such as ethnography would ensure those with communication or cognitive impairment are not excluded from research. Implications for rehabilitationRehabilitation professionals, especially occupational therapists, need to lead acquired brain injury (ABI) research in acute hospital settings in the UK.Conceptualisation of meaningful activity and occupation needs a clearer focus in ABI research.Qualitative studies frequently exclude participants with cognitive or communication impairments so methodologies that are more inclusive and representative of brain injury survivors are needed.

5.
J Evol Biol ; 36(10): 1455-1470, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37731241

RESUMEN

The relative contribution of adaptation and phenotypic plasticity can vary between core and edge populations, with implications for invasive success. We investigated the spread of the invasive yellow monkeyflower, Erythranthe gutatta in New Zealand, where it is spreading from lowland agricultural land into high-elevation conservation areas. We investigated the extent of phenotypic variation among clones from across the South Island, looked for adaptation and compared degrees of plasticity among lowland core versus montane range-edge populations. We grew 34 clones and measured their vegetative and floral traits in two common gardens, one in the core range at 9 m a.s.l. and one near the range-edge at 560 m a.s.l. Observed trait variation was explained by a combination of genotypic diversity (as identified through common gardens) and high phenotypic plasticity. We found a subtle signature of local adaptation to lowland habitats but all clones were plastic and able to survive and reproduce in both gardens. In the range-edge garden, above-ground biomass was on average almost double and stolon length almost half that of the same clone in the core garden. Clones from low-elevation sites showed higher plasticity on average than those from higher elevation sites. The highest performing clones in the core garden were also top performers in the range-edge garden. These results suggest some highly fit general-purpose genotypes, possibly pre-adapted to New Zealand montane conditions, best explains the spread of E. gutatta from lowland to higher elevation areas.


Asunto(s)
Lamiales , Mimulus , Nueva Zelanda , Adaptación Fisiológica/genética , Genotipo , Fenotipo
6.
J Intellect Disabil ; : 17446295231196588, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37611566

RESUMEN

The overall objective of this research was to identify intellectual disability nursing interventions and their impact on the health and healthcare of people with intellectual disability. This is part 3 of a 4-part series. In this paper we report the findings from quantitative questions from an online survey of intellectual disability nurses. The objective of this part of the study was to a evaluate intellectual disability nurses' confidence in their understanding of the interventions they undertook. Quantitative data was collected using an online survey questionnaire from a voluntary response and snowball sample of 230 participants from 7 countries. Thematic, descriptive statistical, and inferential statistical analyses were undertaken. The evaluation data suggest and demonstrate a lack of clarity among intellectual disability nurses of the interventions they can effectively undertake. There appears to be correlations between lack of role clarity and the types of employer organisations and countries. Further work need to be undertaken by nurse leaders ascertain and address this lack of clarity.

7.
Sci Total Environ ; 841: 156756, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35718175

RESUMEN

The Irrawaddy (Ayeyarwaddy) and Salween (Thanlwin) globally rank among the largest rivers for supplying dissolved and particulate material to the ocean. Along with the Sittaung and Kaladan rivers they have societal importance to Myanmar in terms water sources and food production. Despite their importance for global biogeochemical cycles and the ~50 million people who live in their catchments, the chemistry of these rivers is poorly known. This study presents a comprehensive survey of dissolved (<0.22 µm) trace element concentrations (Sr, Fe, Al, Ba, Mn, V, Rb, Cu, Zn, As, Li, Ni, Mo, Cr, U, Pb, Sb, Co, Cs, Tl and Cd) at 38 locations within these river catchments, spanning a period of 2 years. The results highlight the global importance of the Irrawaddy and Salween rivers for trace element global biogeochemical cycles; contributing between 1 and 17 % of global dissolved riverine fluxes to the land-ocean interface for the studied elements. Area normalized dissolved fluxes in these catchments are ~2 to 10 times higher than global average values for most elements, consistent with high rates of chemical weathering. In general, anthropogenic activities have yet to significantly perturb dissolved trace element fluxes in these river systems. The presented dataset should therefore serve as a useful 'natural' baseline, against which future perturbations driven by climate change and/or the development of Myanmar's mining industry could be assessed. Exceptions to this include As in the Sittaung River and Sb, Zn, Pb and As in the Salween River, which may already be significantly impacted by anthropogenic inputs. The former represents a water quality issue of concern for public health, and so constraining the exact sources of As in the Sittaung River should be considered a priority for future research.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados , Ríos , Oligoelementos , Contaminantes Químicos del Agua , Plomo , Metales Pesados/análisis , Mianmar , Ríos/química , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis
8.
Glob Chang Biol ; 28(9): 3066-3082, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35170154

RESUMEN

Significant gaps remain in understanding the response of plant reproduction to environmental change. This is partly because measuring reproduction in long-lived plants requires direct observation over many years and such datasets have rarely been made publicly available. Here we introduce MASTREE+, a data set that collates reproductive time-series data from across the globe and makes these data freely available to the community. MASTREE+ includes 73,828 georeferenced observations of annual reproduction (e.g. seed and fruit counts) in perennial plant populations worldwide. These observations consist of 5971 population-level time-series from 974 species in 66 countries. The mean and median time-series length is 12.4 and 10 years respectively, and the data set includes 1122 series that extend over at least two decades (≥20 years of observations). For a subset of well-studied species, MASTREE+ includes extensive replication of time-series across geographical and climatic gradients. Here we describe the open-access data set, available as a.csv file, and we introduce an associated web-based app for data exploration. MASTREE+ will provide the basis for improved understanding of the response of long-lived plant reproduction to environmental change. Additionally, MASTREE+ will enable investigation of the ecology and evolution of reproductive strategies in perennial plants, and the role of plant reproduction as a driver of ecosystem dynamics.


Aún existen importantes vacíos en la comprensión de la respuesta reproductiva de las plantas al cambio medioambiental, en parte, porque su monitoreo en especies de plantas longevas requiere una observación directa durante muchos años, y estos conjuntos de datos rara vez han estado disponibles. Aquí presentamos a MASTREE +, una base de datos que recopila series de tiempo de la reproducción de las plantas de todo el planeta, poniendo a disposición estos datos de libre acceso para la comunidad científica. MASTREE + incluye 73.828 puntos de observación de la reproducción anual georreferenciados (ej. conteos de semillas y frutos) en poblaciones de plantas perennes en todo el mundo. Estas observaciones consisten en 5971 series temporales a nivel de población provenientes de 974 especies en 66 países. La mediana de la duración de las series de tiempo es de 10 años (media = 12.4 años) y el conjunto de datos incluye 1.122 series de al menos dos décadas (≥20 años de observaciones). Para un subconjunto de especies bien estudiadas, MASTREE +incluye un amplio conjunto de series temporales replicadas en gradientes geográficos y climáticos. Describimos el conjunto de datos de acceso abierto disponible como un archivo.csv y presentamos una aplicación web asociada para la exploración de datos. MASTREE+ proporcionará la base para mejorar la comprensión sobre la respuesta reproductiva de plantas longevas al cambio medioambiental. Además, MASTREE+ facilitará los avances en la investigación de la ecología y la evolución de las estrategias reproductivas en plantas perennes y el papel de la reproducción vegetal como determinante de la dinámica de ecosistemas.


Asunto(s)
Ecosistema , Reproducción , Ecología , Plantas , Semillas/fisiología
9.
J Autism Dev Disord ; 52(5): 2112-2131, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34052971

RESUMEN

Appreciating autistic neurodiversity is important when supporting autistic people who experience distress. Specifically, use of a profiling model can reveal less visible autistic differences, including strengths and abilities. Binary logistic regressions showed that the likelihood of extreme distress responses could be interpreted based on parent-reported autistic thinking pattern profiles for 140 young people. Perspective-taking (specifically empathy), extreme demand avoidance, and over-sensory sensitivity each contributed to the combined regression models. From the clinical perspective of autism as a multi-dimensional and inter-connected construct, there may be implications for planning support and building positive self-understanding. Individually tailored adjustments and support strategies may be identified more easily after delineating variables found across four core aspects: sensory coherence, flexible thinking, perspective-taking, and regulation.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Adolescente , Trastorno del Espectro Autista/diagnóstico , Empatía , Humanos , Padres
10.
PLoS One ; 16(8): e0255638, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34370774

RESUMEN

To what extent birds provide the ecosystem service of pest control in subsistence farms, and how this service might depend on retained natural habitats near farmlands is unexplored in West Africa. To fill this knowledge gap, we placed plasticine mimics of insect pests on experimentally grown crops on the Mambilla Plateau, South Eastern Nigeria. We recorded bird attacks on the mimics and the proportion of mimics removed by birds. We also determined the influence of distance of crops from forest fragments on both attack and removal rates. We placed 90 potted plants of groundnut (Arachis hypogea) and bambara nut (Vigna subterranea) along 15 transects running 4.5 km from forest edge into open grassland. Each plant had six of the 540 mimics in total placed on their leaves. We inspected the potted plants weekly for 12 weeks to record (i) the presence of bird beak marks on mimics, and (ii) the number of missing mimics. Once a week we collected all the mimics from the plants and counted the number of assumed beak marks. After counting we replaced the mimics on the plants, mark free. We found a strong positive correlation between the abundance of insectivorous birds and the mean number of missing mimics and/or bird attack marks on mimics. However, this positive effect of insectivorous bird abundance on prey mimic attack/removal became less strong the farther they were from a forest fragment. We found increased predation rates and abundance of insectivorous birds closer to forest fragments. Our data suggest that pest predation may be a key ecosystem service provided by insectivorous birds on Nigerian farmlands. Farmlands that are closer to forest fragments may experience a higher rate of pest control by insectivorous birds than those further away, suggesting that retaining forest fragments in the landscape may enhance pest control services in sub-Saharan subsistence farms.


Asunto(s)
Aves/fisiología , Conservación de los Recursos Naturales , Protección de Cultivos/métodos , Granjas , Bosques , Control de Insectos/métodos , Conducta Predatoria/fisiología , Animales , Arachis , Productos Agrícolas , Pradera , Insectos , Nigeria , Compuestos Orgánicos , Estaciones del Año , Vigna
11.
Nature ; 596(7873): 536-542, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34433947

RESUMEN

Tropical forests store 40-50 per cent of terrestrial vegetation carbon1. However, spatial variations in aboveground live tree biomass carbon (AGC) stocks remain poorly understood, in particular in tropical montane forests2. Owing to climatic and soil changes with increasing elevation3, AGC stocks are lower in tropical montane forests compared with lowland forests2. Here we assemble and analyse a dataset of structurally intact old-growth forests (AfriMont) spanning 44 montane sites in 12 African countries. We find that montane sites in the AfriMont plot network have a mean AGC stock of 149.4 megagrams of carbon per hectare (95% confidence interval 137.1-164.2), which is comparable to lowland forests in the African Tropical Rainforest Observation Network4 and about 70 per cent and 32 per cent higher than averages from plot networks in montane2,5,6 and lowland7 forests in the Neotropics, respectively. Notably, our results are two-thirds higher than the Intergovernmental Panel on Climate Change default values for these forests in Africa8. We find that the low stem density and high abundance of large trees of African lowland forests4 is mirrored in the montane forests sampled. This carbon store is endangered: we estimate that 0.8 million hectares of old-growth African montane forest have been lost since 2000. We provide country-specific montane forest AGC stock estimates modelled from our plot network to help to guide forest conservation and reforestation interventions. Our findings highlight the need for conserving these biodiverse9,10 and carbon-rich ecosystems.


Asunto(s)
Actitud , Secuestro de Carbono , Carbono/análisis , Bosque Lluvioso , Árboles/metabolismo , Clima Tropical , África , Biomasa , Cambio Climático , Conservación de los Recursos Naturales , Conjuntos de Datos como Asunto , Mapeo Geográfico
12.
Nat Commun ; 12(1): 3137, 2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34035260

RESUMEN

Arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) associations are critical for host-tree performance. However, how mycorrhizal associations correlate with the latitudinal tree beta-diversity remains untested. Using a global dataset of 45 forest plots representing 2,804,270 trees across 3840 species, we test how AM and EcM trees contribute to total beta-diversity and its components (turnover and nestedness) of all trees. We find AM rather than EcM trees predominantly contribute to decreasing total beta-diversity and turnover and increasing nestedness with increasing latitude, probably because wide distributions of EcM trees do not generate strong compositional differences among localities. Environmental variables, especially temperature and precipitation, are strongly correlated with beta-diversity patterns for both AM trees and all trees rather than EcM trees. Results support our hypotheses that latitudinal beta-diversity patterns and environmental effects on these patterns are highly dependent on mycorrhizal types. Our findings highlight the importance of AM-dominated forests for conserving global forest biodiversity.


Asunto(s)
Biodiversidad , Bosques , Micorrizas/fisiología , Árboles/fisiología , Interacciones Microbiota-Huesped/fisiología , Dispersión de las Plantas , Microbiología del Suelo , Árboles/microbiología
13.
PeerJ ; 9: e11036, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33777527

RESUMEN

We test the hypothesis that the tree species previously known as Deinbollia sp. 2. is a new species for science. We formally characterise and name this species as Deinbollia onanae (Sapindaceae-Litchi clade) and we discuss it in the context of the assemblage of montane tree species in the Cameroon Highlands of West-Central Africa. The new species is a shade-bearing, non-pioneer understorey forest tree species reaching 15 m high and a trunk diameter that can attain over 40 cm at 1.3 m above the ground. Seed dispersal has been recorded by chimpanzees (Pan troglodytes ellioti) and by putty-nose monkeys (Cercopithecus nictitans) and the species is used by chimpanzees for nesting. Cameroon has the highest species-diversity and species endemism known in this African-Western Indian Ocean genus of 42, mainly lowland species. Deinbollia onanae is an infrequent tree species known from six locations in surviving islands of montane (sometimes also upper submontane) forest along the line of the Cameroon Highlands, including one at Ngel Nyaki in Mambilla, Nigeria. Deinbollia onanae is here assessed as Endangered according to the IUCN 2012 standard, threatened by severe fragmentation of its mountain forest habitat due to extensive and ongoing clearance for agriculture. The majority of the 28 tree species of montane forest (above 2000 m alt.) in the Cameroon Highlands are also widespread in East African mountains (i.e. are Afromontane wide). Deinbollia onanae is one of only seven species known to be endemic (globally restricted to) these highlands. It is postulated that this new species is morphologically closest to Deinbollia oreophila, a frequent species at a lower (submontane) altitudinal band of the same range. Detailed ecological data on Deinbollia onanae from the Nigerian location, Ngel Nyaki, where it has been known under the name Deinbollia "pinnata", is reviewed.

14.
J Insect Sci ; 20(2)2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32322881

RESUMEN

New Zealand's intensive pastures, comprised almost entirely introduced Lolium L. and Trifolium L. species, are arguably the most productive grazing-lands in the world. However, these areas are vulnerable to destructive invasive pest species. Of these, three of the most damaging pests are weevils (Coleoptera: Curculionidae) that have relatively recently been controlled by three different introduced parasitoids, all belonging to the genus Microctonus Wesmael (Hymenoptera: Braconidae). Arguably that these introduced parasitoids have been highly effective is probably because they, like many of the exotic pest species, have benefited from enemy release. Parasitism has been so intense that, very unusually, one of the weevils has now evolved resistance to its parthenogenetic parasitoid. This review argues that New Zealand's high exotic pasture pest burden is attributable to a lack of pasture plant and natural enemy diversity that presents little biotic resistance to invasive species. There is a native natural enemy fauna in New Zealand that has evolved over millions of years of geographical isolation. However, these species remain in their indigenous ecosystems and, therefore, play a minimal role in creating biotic resistance in the country's exotic ecosystems. For clear ecological reasons relating to the nature of New Zealand pastures, importation biological control can work extremely well. Conversely, conservation biological control is less likely to be effective than elsewhere.


Asunto(s)
Control de Insectos , Control Biológico de Vectores , Avispas/fisiología , Gorgojos/parasitología , Animales , Especies Introducidas , Nueva Zelanda
15.
Behav Processes ; 168: 103953, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31493493

RESUMEN

How rodents perceive predation risk may alter their seed foraging behaviour and therefore potentially influence the recruitment of tree species. In this study we used two methods to investigate the effect of predation risk on habitat use by the African giant pouched rat (Cricetomys sp. nov) in Ngel Nyaki forest reserve, Nigeria. The first method was 'giving up density' (GUD), an index of perceived risk of predation at an artificial food patch, and the second was the 'spool-and-line' approach, whereby unravelling spools attached to rodent bodies are used to trace their tracks. For our GUD experiment, we chose four major sites in the forest; two representative of core habitat and two at the forest edge. Additionally, three characteristic microsites were used in the GUD experiment: dense understory, open understory and near-burrows. We hypothesised that GUDs would be lower on every succeeding observation day as rats learn to use the food patches, higher GUDs would be observed in the forest edges and open microsites, and rats would show preference for the microhabitats with least exposure to potential predators. In support of our first hypothesis, we found that GUDs were highest on the first experimental nights of every session. We also found that GUDs in the forest edges were higher than GUDs in the forest core. Lower GUDs were observed close to the rat burrows and in dense understory microsites, even though these differences were not statistically significant. Tracking of rat movements using the spool-and-line method overall revealed an even use across microhabitats, with a weak preference for those with logs, dense understory or exposed ground. Overall, our results suggest that vegetation density on a microhabitat scale has little or no effect on the perception of predation risk by African giant pouched rats.


Asunto(s)
Ecosistema , Cadena Alimentaria , Bosques , Percepción , Ratas/psicología , Medición de Riesgo , Medio Social , Animales , Nigeria
16.
Nurs Ethics ; 26(7-8): 2085-2097, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30947612

RESUMEN

BACKGROUND: Respectful care is central to ethical codes of practice and optimal patient care, but little is known about the influences on and challenges in communicating respect. RESEARCH QUESTION: What are the intra- and inter-personal influences on nurses' communication of respect? RESEARCH DESIGN AND PARTICIPANTS: Semi-structured interviews with 12 hospital-based UK registered nurses were analysed using interpretative phenomenological analysis to explore their experiences of communicating respect to patients and associated influences. ETHICAL CONSIDERATIONS: The study was approved by the Institutional ethics board and National Health Service Trust. FINDINGS: Three interconnected superordinate themes were identified: 'private self: personal attitudes', 'outward self: showing respect' and 'reputational self: being perceived as respectful'. Respectful communication involved a complex set of influences, including attitudes of respect towards patients, needs and goals, beliefs around the nature of respectful communication, skills and influencing sociocultural factors. A tension between the outward self as intended and perceived presented challenges for nurses' reputational self as respectful, with negative implications for patient care. DISCUSSION: The study offers an in-depth understanding of intra- and inter-personal influences on communicating respect, and sheds light on challenges involved, helping provide practical insights to support respectful care. CONCLUSION: Findings stress the need for improved conceptualisations of respect in healthcare settings to formally recognise the complex attitudinal and socially constructed nature of respect and for appropriate professional training to improve its communication.


Asunto(s)
Relaciones Enfermero-Paciente , Enfermeras y Enfermeros/psicología , Respeto , Adulto , Inglaterra , Femenino , Humanos , Entrevistas como Asunto/métodos , Masculino , Persona de Mediana Edad , Enfermeras y Enfermeros/estadística & datos numéricos , Investigación Cualitativa
17.
Ecol Lett ; 22(2): 245-255, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30548766

RESUMEN

Climate is widely recognised as an important determinant of the latitudinal diversity gradient. However, most existing studies make no distinction between direct and indirect effects of climate, which substantially hinders our understanding of how climate constrains biodiversity globally. Using data from 35 large forest plots, we test hypothesised relationships amongst climate, topography, forest structural attributes (stem abundance, tree size variation and stand basal area) and tree species richness to better understand drivers of latitudinal tree diversity patterns. Climate influences tree richness both directly, with more species in warm, moist, aseasonal climates and indirectly, with more species at higher stem abundance. These results imply direct limitation of species diversity by climatic stress and more rapid (co-)evolution and narrower niche partitioning in warm climates. They also support the idea that increased numbers of individuals associated with high primary productivity are partitioned to support a greater number of species.


Asunto(s)
Biodiversidad , Árboles , Clima
18.
PLoS One ; 13(8): e0202010, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30110399

RESUMEN

Amphibians are the vertebrate group with the highest number of species threatened with extinction, and habitat loss and fragmentation are considered to be among the leading causes of their declines and extinctions. Little is known of the population biology of amphibian species inhabiting montane forests in Central and West Africa, where anthropogenic activities such as farming and cattle raising are major threats to native biodiversity. We used Amplified Fragment Length Polymorphisms (AFLPs) to assess the population genetic structure of two poorly known species, Cardioglossa schioetzi and Leptodactylodon bicolor (both in the Arthroleptidae), in and around Ngel Nyaki Forest Reserve on the Mambilla Plateau in eastern Nigeria. The landscape comprises continuous forest on steep slopes and small riparian forest fragments in a grassland matrix. While increased fragmentation is well documented for these and other forests in the mountains of Cameroon and Nigeria over the past century, there are no previous assessments of the impact of forest fragmentation on montane amphibian populations in this region. Our estimates of genetic diversity are similar across populations within each species with levels of heterozygosity values consistent with local population declines. Except for a pair of populations (C. schioetzi) we did not observe genetic differentiation between forest and riparian forest fragment populations, nor across sites within continuous forest (L. bicolor). Our results demonstrate recent gene flow between forest fragments and the adjacent protected forests and suggest that small forest corridors connecting these may lessen the genetic consequences of at least 30 years of intense and severe fragmentation in Ngel Nyaki.


Asunto(s)
Anuros/genética , Variación Genética , Genética de Población , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Animales , Anuros/clasificación , Biodiversidad , Heterogeneidad Genética , Geografía , Nigeria , Polimorfismo Genético
19.
Genome Announc ; 5(9)2017 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-28254982

RESUMEN

Metagenomic approaches are rapidly expanding our knowledge of the diversity of viruses. In the fecal matter of Nigerian chimpanzees we recovered three gokushovirus genomes, one circular replication-associated protein encoding single-stranded DNA virus (CRESS), and a CRESS DNA molecule.

20.
PLoS One ; 12(3): e0173079, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28328951

RESUMEN

We conducted a multi-isotope study of five fifth-century AD cemeteries in modern-day Hungary to determine relationships between nomadic-pastoralist incomers-the historically documented Huns and other nomadic groups-and the sedentary agricultural population of the late Roman province of Pannonia. Contemporary historical sources describe this relationship as adversarial and destructive for the late Roman population, but archaeological evidence indicates high levels of hybridity between different groups. We undertook carbon, nitrogen, strontium and oxygen isotope analyses of bone collagen, dentine and tooth enamel at Keszthely-Fenékpuszta, Hács-Béndekpuszta, Gyor-Széchenyi Square, Mözs and Szolnok-Szanda to examine these relationships through past subsistence practices. The patterns at all sites indicate medium to high animal protein consumption with little evidence for a significant contribution of aquatic resources. All populations relied to a great extent on C4 plants, most likely millet. Within each population, diet was heterogeneous, with significant variations in terms of animal protein and C3 and C4 plant consumption. High levels of intra-population and individual variability suggest that populations made use of a range of subsistence strategies, with many individuals exhibiting significant changes over their lifetimes. Rather than being characterised only by violence, the historically-documented influx of nomadic populations appears to have led to widespread changes in subsistence strategies of populations in the Carpathian basin. Nomadic-pastoralist groups may have switched to smaller herds and more farming, and, conversely, local populations may have integrated with a new economic system based on animal herding.


Asunto(s)
Isótopos de Carbono/química , Isótopos de Nitrógeno/química , Agricultura/métodos , Animales , Arqueología/métodos , Huesos/química , Cementerios , Colágeno/análisis , Esmalte Dental/química , Ambiente , Humanos , Hungría , Plantas/química
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