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2.
Commun Biol ; 7(1): 950, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107559

RESUMO

A significant warming effect on arctic tundra is greening. Although this increase in predominantly woody vegetation has been linked to increases in gross primary productivity, increasing temperatures also stimulate ecosystem respiration. We present a novel analysis from small-scale plot measurements showing that the shape of the temperature- and light-dependent sink-to-source threshold (where net ecosystem exchange (NEE) equals zero) differs between two tussock tundra ecosystems differing in leaf area index (LAI). At the higher LAI site, the threshold is exceeded (i.e the ecosystem becomes a source) at relatively higher temperatures under low light but at lower temperatures under high light. At the lower LAI site, the threshold is exceeded at relatively lower temperatures under low light but at higher temperatures under high light. We confirmed this response at a single site where LAI was experimentally increased. This suggests the carbon balance of the tundra may be sensitive to small increases in temperature under low light, but that this effect may be significantly offset by increases in LAI. Importantly, we found that this LAI effect is reversed under high light, and so in a warming tundra, greater vegetation cover could have a progressively negative effect on net carbon uptake.


Assuntos
Luz , Temperatura , Tundra , Regiões Árticas , Sequestro de Carbono , Carbono/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Ecossistema , Mudança Climática
3.
J Anim Ecol ; 93(9): 1303-1315, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39073110

RESUMO

Following a resource pulse, animals may finance reproduction by consuming concurrently available resources (income breeding) or by storing resources for future reproduction (capital breeding). Understanding how these reproductive strategies are used is important for determining the ecological mechanisms that structure timing of reproduction and that drive interannual population fluctuations in animals. We gathered a reproductive dataset for five small mammal species over a 12-year period in Northeastern USA during which six masting events of American beech (Fagus grandifolia) and eastern hemlock (Tsuga canadensis) occurred. Masting created alternate years where seeds were either available late (masting year) or early (cached from the previous year) in the breeding season. The small mammal species differed in reliance on seeds and overwintering strategies. We quantified the diet using stable isotopes and recorded reproduction timing, proportion breeding and litter size in females and testes size in males. Timing of seed availability minimally affected litter size but strongly affected proportion breeding and timing of reproduction. During masting years (late seed availability), a higher proportion of females reproduced, with breeding taking place later in the season (lactation timed with peak seed availability), although the delay was restricted in Napaeozapus insignis, an obligate hibernator. After a fall mast, cached seeds were used as capital in the following spring (early seed availability) to support a litter that, depending on the species, occurred 24-79 days sooner than a mast year. No late-season reproduction occurred in years with early seed availability except for Myodes gapperi which produced a second litter, likely financed by fungal consumption. Males also showed strong responses to seed availability, mirroring female reproduction with testes size staying constant in years with late seed availability and sharply decreasing over the breeding season in years with early seed availability. Our results highlight that although photoperiod and temperature broadly set bounds of the breeding season in temperate environments, resource availability influences the reproductive strategies that species use, which in turn alters reproductive timing and can drive large inter-annual population fluctuations. Differences in overwintering strategies and diet may further modulate reproductive timing and output relative to resource pulses.


Assuntos
Reprodução , Estações do Ano , Animais , Feminino , Masculino , Dieta/veterinária , Sementes , Tamanho da Ninhada de Vivíparos , Fagus/fisiologia , Testículo/fisiologia , Testículo/anatomia & histologia
6.
Med Sci Educ ; 34(1): 273-276, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38510408

RESUMO

The Spring 2023 Webinar Audio Seminar (WAS) of the International Association of Medical Science Educators (IAMSE), titled "Widening the Road to Health Professions Education: Expanding Access for Diverse and Underserved Populations," was designed to help health science educators explore innovative practices in recruiting and enrolling students from underserved populations into health sciences programs. From March 2, 2023, to March 30, 2023, this five-part webinar series was broadcast live to institutions and educators worldwide. This series helped participants learn about creating pathways for students to meet the unique needs of their communities.

8.
J Cosmet Dermatol ; 22(10): 2650-2662, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37550898

RESUMO

BACKGROUND: Topical azelaic acid (AA) is indicated for acne and rosacea, but there is some evidence for its use for other dermatological conditions. AIMS: To assess the effectiveness and safety of topical AA for acne vulgaris, rosacea, hyperpigmentation/melasma, and skin aging. METHODS: RCTs of at least 6 weeks' treatment duration were eligible for inclusion. Databases including MEDLINE, Embase, CINAHL, and ClinicalTrials.gov were searched up to December 2022. Two reviewers were involved in all stages of the systematic review process. RESULTS: Forty-three RCTs met the inclusion criteria. Meta-analyses within 20 rosacea studies demonstrated that erythema severity, inflammatory lesion counts, overall improvement, and treatment success (achieving skin clarity) were significantly improved with AA compared with vehicle after 12 weeks. AA was more effective than metronidazole 0.75% for improved erythema severity, overall improvement, and inflammatory lesion counts. Sixteen acne studies suggest that AA is more effective than vehicle for improving global assessments and reducing acne severity. AA 20% also significantly reduced more lesions than erythromycin gel. Within seven melasma studies, AA 20% was significantly better than vehicle for both severity and global improvement. AA 20% demonstrated significantly better results compared with hydroquinone 2% for global improvement. Very few significant differences between AA and comparators were observed for commonly reported adverse events. No eligible RCTs were found that evaluated skin aging. CONCLUSIONS: AA is more effective than vehicle for rosacea, acne and melasma. Comparisons between AA and other treatments were often equivalent. Where there is equivalence, AA may be a good option for some clinical situations. RCT evidence is needed to evaluate the effectiveness of AA on skin aging.


Assuntos
Acne Vulgar , Fármacos Dermatológicos , Melanose , Rosácea , Envelhecimento da Pele , Humanos , Acne Vulgar/tratamento farmacológico , Rosácea/tratamento farmacológico , Rosácea/patologia , Eritema/tratamento farmacológico , Resultado do Tratamento , Melanose/tratamento farmacológico , Fármacos Dermatológicos/efeitos adversos
10.
Ecology ; 104(6): e4039, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36960918

RESUMO

Following a disturbance, dispersal shapes community composition as well as ecosystem structure and function. For fungi, dispersal is often wind or mammal facilitated, but it is unclear whether these pathways are complementary or redundant in the taxa they disperse and the ecosystem functions they provide. Here, we compare the diversity and morphology of fungi dispersed by wind and three rodent species in recently harvested forests using a combination of microscopy and Illumina sequencing. We demonstrate that fungal communities dispersed by wind and small mammals differ in richness and composition. Most wind-dispersed fungi are wood saprotrophs, litter saprotrophs, and plant pathogens, whereas fungi dispersed in mammal scat are primarily mycorrhizal, soil saprotrophs, and unspecified saprotrophs. We note substantial dispersal of truffles and agaricoid mushrooms by small mammals, and dispersal of agaricoid mushrooms, crusts, and polypores by wind. In addition, we find mammal-dispersed spores are larger than wind-dispersed spores. Our findings suggest that wind- and small-mammal-facilitated dispersal are complementary processes and highlight the role of small mammals in dispersing mycorrhizal fungi, particularly following disturbances such as timber harvest.


Assuntos
Ecossistema , Micorrizas , Animais , Vento , Florestas , Mamíferos , Roedores , Microbiologia do Solo , Fungos , Solo , Esporos Fúngicos
11.
Glob Change Biol Bioenergy ; 15(4): 444-461, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38505760

RESUMO

New biomass crop hybrids for bioeconomic expansion require yield projections to determine their potential for strategic land use planning in the face of global challenges. Our biomass growth simulation incorporates radiation interception and conversion efficiency. Models often use leaf area to predict interception which is demanding to determine accurately, so instead we use low-cost rapid light interception measurements using a simple laboratory-made line ceptometer and relate the dynamics of canopy closure to thermal time, and to measurements of biomass. We apply the model to project the European biomass potentials of new market-ready hybrids for 2020-2030. Field measurements are easier to collect, the calibration is seasonally dynamic and reduces influence of weather variation between field sites. The model obtained is conservative, being calibrated by crops of varying establishment and varying maturity on less productive (marginal) land. This results in conservative projections of miscanthus hybrids for 2020-2030 based on 10% land use conversion of the least (productive) grassland and arable for farm diversification, which show a European potential of 80.7-89.7 Mt year-1 biomass, with potential for 1.2-1.3 EJ year-1 energy and 36.3-40.3 Mt year-1 carbon capture, with seeded Miscanthus sacchariflorus × sinensis displaying highest yield potential. Simulated biomass projections must be viewed in light of the field measurements on less productive land with high soil water deficits. We are attempting to model the results from an ambitious and novel project combining new hybrids across Europe with agronomy which has not been perfected on less productive sites. Nevertheless, at the time of energy sourcing issues, seed-propagated miscanthus hybrids for the upscaled provision of bioenergy offer an alternative source of renewable energy. If European countries provide incentives for growers to invest, seeded hybrids can improve product availability and biomass yields over the current commercial miscanthus variety.

12.
Glob Change Biol Bioenergy ; 15(5): 538-558, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-38505831

RESUMO

Demand for sustainably produced biomass is expected to increase with the need to provide renewable commodities, improve resource security and reduce greenhouse gas emissions in line with COP26 commitments. Studies have demonstrated additional environmental benefits of using perennial biomass crops (PBCs), when produced appropriately, as a feedstock for the growing bioeconomy, including utilisation for bioenergy (with or without carbon capture and storage). PBCs can potentially contribute to Common Agricultural Policy (CAP) (2023-27) objectives provided they are carefully integrated into farming systems and landscapes. Despite significant research and development (R&D) investment over decades in herbaceous and coppiced woody PBCs, deployment has largely stagnated due to social, economic and policy uncertainties. This paper identifies the challenges in creating policies that are acceptable to all actors. Development will need to be informed by measurement, reporting and verification (MRV) of greenhouse gas emissions reductions and other environmental, economic and social metrics. It discusses interlinked issues that must be considered in the expansion of PBC production: (i) available land; (ii) yield potential; (iii) integration into farming systems; (iv) R&D requirements; (v) utilisation options; and (vi) market systems and the socio-economic environment. It makes policy recommendations that would enable greater PBC deployment: (1) incentivise farmers and land managers through specific policy measures, including carbon pricing, to allocate their less productive and less profitable land for uses which deliver demonstrable greenhouse gas reductions; (2) enable greenhouse gas mitigation markets to develop and offer secure contracts for commercial developers of verifiable low-carbon bioenergy and bioproducts; (3) support innovation in biomass utilisation value chains; and (4) continue long-term, strategic R&D and education for positive environmental, economic and social sustainability impacts.

13.
Med Sci Educ ; 32(5): 1239-1245, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36276773

RESUMO

Interprofessional training, social sciences curricula, service-learning, pre-clerkship integration, and self-directed learning are all cornerstones of medical education and closely align with accreditation elements for most accreditation bodies within health professions education. As a sequel to the Winter 2022 series, the Spring 2022 Webcast Audio Seminar (WAS) of the International Association of Medical Science Educators (IAMSE) continued to examine the evolving roles of basic science educators. From March 3 to March 31, 2022, the five-part webinar series was broadcast live to audiences at academic institutions worldwide; recordings are available on the IAMSE website. This series built a framework through which basic scientists can leverage their content to meet various accreditation standards.

15.
Ecology ; 103(7): e3689, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35324006

RESUMO

Fire is an important ecological disturbance that can reset ecosystems and initiate changes in plant community composition, ecosystem biogeochemistry, and primary productivity. As herbivores rely on primary producers for food, changes in vegetation may alter plant-herbivore interactions with important-but often unexplored-feedbacks to ecosystems. Here we examined the impact of post-fire changes in plant community composition and structure on habitat suitability and rodent herbivore activity in response to a large, severe, and unprecedented fire in northern Alaskan tundra. In moist acidic tundra where the fire occurred, tundra voles (Microtus oeconomus) are the dominant herbivore and rely on the tussock forming sedge Eriophorum vaginatum for both food and nesting material. Tundra voles were 10 times more abundant at the burned site compared with nearby unburned tundra 7-12 years after the fire. Fire increased the habitat suitability for voles by increasing plant productivity and biomass, food quality, and cover through both taller vegetation and increased microtopography. As a result of elevated vole abundance, Eriophorum mortality caused by vole herbivory was two orders of magnitude higher than natural mortality and approached the magnitude of the mortality rate resulting directly from the fire. These findings suggest that post-fire increases in herbivore pressure on Eriophorum could, in turn, disrupt graminoid recovery and enhance shrub encroachment. Tundra state transitions from graminoid to shrub dominated are also evident following other disturbances and fertilization experiments, suggesting that as Arctic temperatures rise, greater available nutrients and increased frequencies of large-scale disturbances may also alter plant-animal interactions with cascading impacts on plant communities and ecosystem function.


Assuntos
Ecossistema , Herbivoria , Animais , Regiões Árticas , Arvicolinae , Plantas , Tundra
16.
Med Sci Educ ; 32(2): 591-597, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35194523

RESUMO

The virtual age of learning is no longer a concern of the future. It is here. The Fall 2021 Webinar Audio Series (WAS) of the International Association of Medical Science Educators (IAMSE), titled "Back to the Future: Maximizing Student Learning and Wellbeing in the Virtual Age," was designed to help health science educators equip themselves with tools to teach the next generation of health care professionals successfully. From September 2, 2021 to September 30, 2021, the Fall 2021 Series was broadcast live to audiences at academic institutions worldwide in five weekly webinars. This five-part webinar series explored theories and best practices in delivering content over virtual and online media while simultaneously promoting a positive learning environment and enhanced student wellbeing.

17.
Int J Lang Commun Disord ; 57(2): 422-440, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35060665

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has renewed interest in the use of ultrasound (US) amongst dysphagia-trained clinicians working with infants and children. US is a portable, minimally intrusive tool which carries reduced risk of aerosol-generation provoked by other instrumental swallowing assessment tools such as fibreoptic endoscopic evaluation of swallowing (FEES). For this reason, US could be a valuable addition to the dysphagia assessment toolkit. A recently published rapid review of US evidence for the assessment of swallowing and laryngeal function in the adult population provided a framework for this neonatal and paediatric review. AIMS: This enhanced rapid review aimed to establish the applicability of US as an instrumental assessment tool for sucking, swallowing and laryngeal function in the neonatal and paediatric populations. METHODS & PROCEDURES: A rapid review of six electronic databases was conducted to identify articles using US to assess sucking, swallowing or laryngeal function in the selected populations, compared with varied reference tests. Abstract screening was completed according to pre-defined inclusion/exclusion criteria with 10% of articles assessed by a second screener. Data was extracted from the included studies using a pre-developed form. A modified QUADAS-2 tool was used to assess study quality. Results from the included studies were summarised and grouped into sucking, swallowing and laryngeal function data. OUTCOMES & RESULTS: Twelve studies using US in the assessment of swallowing and/or laryngeal function met inclusion criteria. No studies using US for assessment of sucking met the inclusion criteria. All were peer-reviewed, primary studies across a range of clinical populations and with a wide geographical spread. Five studies had an overall low risk of bias. Seven studies had at least one domain where risk of bias was judged as high. All studies had high applicability. The two studies assessing swallowing differed in terms of aims and use of US. The studies assessing laryngeal function predominately investigated vocal fold movement and laryngeal pathology. Sensitivity and specificity data were provided or calculated from raw data for nine of the laryngeal function studies (respective ranges of 75%-100% and 80%-100%). CONCLUSIONS & IMPLICATIONS: Emerging evidence exists to support the use of US as adjunct to clinical assessment of swallowing and laryngeal function in the neonatal and paediatric population. A paucity of evidence to support use of US in the assessment of sucking exists. Further research is needed to establish evidence-based assessment and analysis protocols as well as development of paediatric data.


Assuntos
COVID-19 , Transtornos de Deglutição , Laringe , Adulto , Criança , Deglutição , Transtornos de Deglutição/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Laringe/diagnóstico por imagem , Ultrassonografia
18.
Midwifery ; 105: 103222, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34965498

RESUMO

BACKGROUND: Vaccination against pertussis and seasonal influenza is recommended for all pregnant women in the UK. More recently COVID-19 vaccination has also been offered to women in pregnancy. OBJECTIVES: To evaluate the uptake of vaccines in pregnant women within a midwife-led immunisation clinic and to assess factors influencing pregnant women's decisions about accepting vaccination. METHODS: Uptake of vaccines amongst pregnant women referred to a single UK centre for antenatal care between 01/01/19 and 02/10/19 was assessed. Interviews with 20 pregnant women explored views of antenatal vaccination and experiences of the vaccination service. FINDINGS: Amongst 4420 women, uptake was 90.6% for pertussis and 78.8% for influenza vaccines. Factors influencing vaccine-related decision-making amongst 20 interviewed women were: healthcare professional recommendation, perceived susceptibility and risk of infection, and previous experience of vaccination and vaccine-preventable disease. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Uptake of pertussis and influenza vaccines within a secondary care immunisation service was higher than the national or regional average. The model of vaccine delivery was associated with high levels of satisfaction. This model of vaccine delivery could be implemented elsewhere to increase vaccine uptake, and should be considered for delivery of COVID-19 vaccines in the future.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Vacinas contra COVID-19 , Feminino , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Vacina contra Coqueluche , Gravidez , Gestantes , SARS-CoV-2 , Centros de Atenção Terciária , Reino Unido , Vacinação
19.
Glob Change Biol Bioenergy ; 14(11): 1205-1218, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36632359

RESUMO

To achieve net zero greenhouse gas emission by 2050 as set out by the 2019 amendment to the 2008 UK Climate Change Act, a major shift towards renewable energy is needed. This includes the development of new methods along with improving and upscaling existing technologies. One example of new methods in bioenergy is developing new Miscanthus cultivars for electricity generation via thermal power station furnaces. Miscanthus is still relatively new compared with other agriculture practices, so market assessments and improvements are needed to reduce the barriers to entry for prospective growers. This publication provides a profile of UK Miscanthus growers and their businesses, their experiences of benefits and drawbacks of the crop, and what they see as potential barriers to entry for prospective farmers. A survey of current Miscanthus growers in England and Wales was conducted and indicated that most farmers were content with the crop and that its environmental and economic benefits were noted. However, it was evident that with a geographically limited UK market, growers wanted to see a better distribution of biomass processing stations to reduce the ongoing costs of transport. With growing demand for renewables, including bio-energy sources, it was determined important to provide information and support for stable farming operations and to incentivise the adoption of Miscanthus. Such incentives include ongoing development of new cultivars, focussing on traits such as production potential and stressor resilience, and growers indicated preference for an annual planting grant. These developments are predicted to further improve the crop's profit margin, making it a more cost-effective crop for farmers. Sensitively managed Miscanthus also has the potential to contribute to carbon sequestration, soil health, and aspects of farmland biodiversity. Incentivising such management in government land-based environmental schemes would offer additional income streams and help to promote environmental positive crop planting.

20.
Ecol Appl ; 32(1): e02478, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34657358

RESUMO

We use a simple model of coupled carbon and nitrogen cycles in terrestrial ecosystems to examine how "explicitly representing grazers" vs. "having grazer effects implicitly aggregated in with other biogeochemical processes in the model" alters predicted responses to elevated carbon dioxide and warming. The aggregated approach can affect model predictions because grazer-mediated processes can respond differently to changes in climate compared with the processes with which they are typically aggregated. We use small-mammal grazers in a tundra as an example and find that the typical three-to-four-year cycling frequency is too fast for the effects of cycle peaks and troughs to be fully manifested in the ecosystem biogeochemistry. We conclude that implicitly aggregating the effects of small-mammal grazers with other processes results in an underestimation of ecosystem response to climate change, relative to estimations in which the grazer effects are explicitly represented. The magnitude of this underestimation increases with grazer density. We therefore recommend that grazing effects be incorporated explicitly when applying models of ecosystem response to global change.


Assuntos
Dióxido de Carbono , Ecossistema , Animais , Regiões Árticas , Mudança Climática , Mamíferos , Tundra
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