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1.
J Med Ethics ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38964775

RESUMO

The sensitivity of human tissue and previous instances of misuse have, rightfully, led to the introduction of far-reaching oversight and regulatory mechanisms for accessing, storing and sharing samples. However, these restrictions, in tandem with more broad-based privacy regulations, have had the unintended consequence of obstructing legitimate requests for medical materials. This is of real detriment to ambitions for biomedical research, most notably the precision medicine agenda. As such, this paper makes the case for facilitating authorised researcher access to human tissue and associated data along practical medical ethics lines, detailing how liberating samples from unfit regulations, re-evaluating biobanks, diversifying considerations for donor benefit-risk, future proofing donor consent and flattening hierarchies of donation acceptability equate to a more cohesive and respectful means of managing biological samples and information than is achieved at present.

2.
J Acoust Soc Am ; 155(3): 2075-2086, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38477611

RESUMO

Baleen whales use sounds of various characteristics for different tasks and interactions. This study focuses on recordings from the Costa Rica Rift, in the Eastern Tropical Pacific Ocean, made by 25 ocean-bottom seismographs and a vertical array of 12 hydrophones between January and February 2015. The whale calls observed are of two kinds: more commonly, repetitive 4-5 s-long signals separated into two frequency bands centered at ∼20 and ∼36 Hz; less commonly, a series of ∼0.5 to 1.0 s-long, lower amplitude signals with frequencies between 80 and 160 Hz. These characteristics are similar to calls attributed to Bryde's whales which are occasionally sighted in this region. In this study, the repetitive calls are detected using both the short-term average/long-term average approach and a network empirical subspace detector. In total, 188 and 1891 calls are obtained for each method, demonstrating the value of the subspace detector for highly similar signals. These signals are first localized using a non-linear grid search algorithm and then further relocalized using the double-difference technique. The high-resolution localizations reveal the presence of at least seven whales during the recording period, often crossing the instrument network from southwest to northeast.


Assuntos
Balaenoptera , Animais , Cetáceos , Som , Oceano Pacífico , Costa Rica , Vocalização Animal
3.
Ann Fam Med ; (21 Suppl 1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36944089

RESUMO

Background The effectiveness of repurposed treatments with supportive evidence for higher risk individuals with COVID-19 in the community is unknown. In the UK PRINCIPLE national platform trial we aimed to determine whether 're-purposed medicines' (hydroxychloroquine, azithromycin, doxycycline, colchicine, inhaled budesonide, and other interventions) reduced time to recovery and COVID-19 related hospitalisations/deaths among people at higher risk of COVID-19 complications in the community. We mainly report the findings for budesonide arm here. Methods Participants in this multicentre, open-label, multi-arm, adaptive platform randomised controlled trial were aged ≥65, or ≥50 years with comorbidities, and unwell ≤14 days with suspected COVID-19 in the community, and were randomised to usual care, usual care plus inhaled budesonide (800µg twice daily for 14 days), or usual care plus other interventions. The co-primary endpoints are time to first self-reported recovery, and hospitalisation/death related to COVID-19, within 28 days, analysed using Bayesian models. Trial registration: ISRCTN86534580. Funded by United Kingdom Research Innovation (MC_PC_19079). Findings The trial opened on April 2, 2020, with the first 4 intervention arms stopped on futility grounds. Randomisation to the budesonide arm occurred from November 27, 2020 until March 31, 2021, when the pre-specified time to recovery superiority criterion was met. The primary analysis model includes 2530 SARS-CoV-2 positive participants, randomised to budesonide (n=787), usual care (n=1069), and other treatments (n=674). Time to first self-reported recovery was shorter in the budesonide group versus usual care (hazard ratio 1·21 [95% credible interval 1·08 to 1·36], probability of superiority >O·999, estimated benefit 2·94 [95% credible interval 1·19 to 5·12] days). An estimated 6·8% COVID-19 related hospitalisations/deaths occurred in the budesonide group versus 8·8% in usual care (estimated absolute difference, 2·0% [95% credible interval -0.2% to 4.5%], probability of superiority 0.963). In the main secondary analysis of admissions using only concurrent controls, admissions occurred in 6.6% (3.8 to 10.1%) in the budesonide group versus 8.8% (95% CI 5.2 to 13.1%), with an absolute difference of 2.2% (0.0 to 4.9%) and a hazard ratio of 0.73 (0.53 to 1.00), meeting the pre-specified superiority probability of 0.975. Three serious adverse events occurred in the budesonide group and three in usual care.


Assuntos
COVID-19 , Humanos , Budesonida/efeitos adversos , SARS-CoV-2 , Teorema de Bayes , Reino Unido/epidemiologia , Resultado do Tratamento
4.
PLoS Med ; 19(2): e1003927, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35192598

RESUMO

BACKGROUND: Several countries restricted the administration of ChAdOx1 to older age groups in 2021 over safety concerns following case reports and observed versus expected analyses suggesting a possible association with cerebral venous sinus thrombosis (CVST). Large datasets are required to precisely estimate the association between Coronavirus Disease 2019 (COVID-19) vaccination and CVST due to the extreme rarity of this event. We aimed to accomplish this by combining national data from England, Scotland, and Wales. METHODS AND FINDINGS: We created data platforms consisting of linked primary care, secondary care, mortality, and virological testing data in each of England, Scotland, and Wales, with a combined cohort of 11,637,157 people and 6,808,293 person years of follow-up. The cohort start date was December 8, 2020, and the end date was June 30, 2021. The outcome measure we examined was incident CVST events recorded in either primary or secondary care records. We carried out a self-controlled case series (SCCS) analysis of this outcome following first dose vaccination with ChAdOx1 and BNT162b2. The observation period consisted of an initial 90-day reference period, followed by a 2-week prerisk period directly prior to vaccination, and a 4-week risk period following vaccination. Counts of CVST cases from each country were tallied, then expanded into a full dataset with 1 row for each individual and observation time period. There was a combined total of 201 incident CVST events in the cohorts (29.5 per million person years). There were 81 CVST events in the observation period among those who a received first dose of ChAdOx1 (approximately 16.34 per million doses) and 40 for those who received a first dose of BNT162b2 (approximately 12.60 per million doses). We fitted conditional Poisson models to estimate incidence rate ratios (IRRs). Vaccination with ChAdOx1 was associated with an elevated risk of incident CVST events in the 28 days following vaccination, IRR = 1.93 (95% confidence interval (CI) 1.20 to 3.11). We did not find an association between BNT162b2 and CVST in the 28 days following vaccination, IRR = 0.78 (95% CI 0.34 to 1.77). Our study had some limitations. The SCCS study design implicitly controls for variables that are constant over the observation period, but also assumes that outcome events are independent of exposure. This assumption may not be satisfied in the case of CVST, firstly because it is a serious adverse event, and secondly because the vaccination programme in the United Kingdom prioritised the clinically extremely vulnerable and those with underlying health conditions, which may have caused a selection effect for individuals more prone to CVST. Although we pooled data from several large datasets, there was still a low number of events, which may have caused imprecision in our estimates. CONCLUSIONS: In this study, we observed a small elevated risk of CVST events following vaccination with ChAdOx1, but not BNT162b2. Our analysis pooled information from large datasets from England, Scotland, and Wales. This evidence may be useful in risk-benefit analyses of vaccine policies and in providing quantification of risks associated with vaccination to the general public.


Assuntos
Vacina BNT162 , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , SARS-CoV-2/patogenicidade , Trombose dos Seios Intracranianos/etiologia , Adulto , Idoso , Vacina BNT162/efeitos adversos , Vacinas contra COVID-19/efeitos adversos , Estudos de Casos e Controles , ChAdOx1 nCoV-19/efeitos adversos , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Reino Unido , Vacinação/estatística & dados numéricos , País de Gales
5.
Environ Microbiol ; 24(8): 3655-3671, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35506306

RESUMO

Fertilizers are costly inputs into crop systems. To compensate for inefficiencies and losses from soil, farmers apply on average double the amount of nitrogen (N) fertilizer acquired by crops. We explored if N efficiency improves with biofertilizers formulated with organic waste, mineral N or plant growth-promoting rhizobacteria (PGPR). We compared treatments receiving mineral N fertilizer or biofertilizers at industry-recommended (100%) or lower (60%) N rates at two commercial sugarcane farms. Biofertilizer at the 60% N-rate generated promising results at one farm with significantly higher biomass and sugar yield than the no-N control, which matched the 100% mineral N treatment. This yield difference was accompanied by a shift in microbial diversity and composition. Correlation analysis confirmed that shifts in microbial communities were strongly linked to soil mineral N levels, as well as crop productivity and yield. Microbial co-occurrence networks further revealed that biofertilizer, including treatments with an added PGPR, can enhance bacterial associations, especially in the context of complex fungal networks. Collectively, the results confirm that biofertilizers have quantifiable effects on soil microbial communities in a crop system setting, which underscores the opportunities for biofertilizers to promote N use efficiency and the circular N economy.


Assuntos
Fertilizantes , Saccharum , Grão Comestível , Fertilizantes/análise , Minerais , Nitrogênio/análise , Solo
6.
Br J Psychiatry ; 221(1): 417-424, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35249568

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) has disproportionately affected people with mental health conditions. AIMS: We investigated the association between receiving psychotropic drugs, as an indicator of mental health conditions, and COVID-19 vaccine uptake. METHOD: We conducted a cross-sectional analysis of a prospective cohort of the Northern Ireland adult population using national linked primary care registration, vaccination, secondary care and pharmacy dispensing data. Univariable and multivariable logistic regression analyses investigated the association between anxiolytic, antidepressant, antipsychotic, and hypnotic use and COVID-19 vaccination status, accounting for age, gender, deprivation and comorbidities. Receiving any COVID-19 vaccine was the primary outcome. RESULTS: There were 1 433 814 individuals, of whom 1 166 917 received a COVID-19 vaccination. Psychotropic medications were dispensed to 267 049 people. In univariable analysis, people who received any psychotropic medication had greater odds of receiving COVID-19 vaccination: odds ratio (OR) = 1.42 (95% CI 1.41-1.44). However, after adjustment, psychotropic medication use was associated with reduced odds of vaccination (ORadj = 0.90, 95% CI 0.89-0.91). People who received anxiolytics (ORadj = 0.63, 95% CI 0.61-0.65), antipsychotics (ORadj = 0.75, 95% CI 0.73-0.78) and hypnotics (ORadj = 0.90, 95% CI 0.87-0.93) had reduced odds of being vaccinated. Antidepressant use was not associated with vaccination (ORadj = 1.02, 95% CI 1.00-1.03). CONCLUSIONS: We found significantly lower odds of vaccination in people who were receiving treatment with anxiolytic and antipsychotic medications. There is an urgent need for evidence-based, tailored vaccine support for people with mental health conditions.


Assuntos
Ansiolíticos , Antipsicóticos , COVID-19 , Adulto , Ansiolíticos/uso terapêutico , Antidepressivos/uso terapêutico , Antipsicóticos/uso terapêutico , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Estudos Transversais , Humanos , Hipnóticos e Sedativos/uso terapêutico , Estudos Prospectivos , Psicotrópicos/uso terapêutico , Vacinação
7.
Nanotechnology ; 33(47)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35944508

RESUMO

In this work, we report the fabrication and spectroscopic characterization of subwavelength aluminum nanocavities-consisting of hexamer or tetramer clusters of sub 10 nm width Al nanorods-with tunable localized surface plasmon resonance (LSPR) energies on suspended SiNxmembranes. Here the volume plasmon (VP) and LSPR modes of lithographically-fabricated Al nanocavities are revealed by low-loss electron energy-loss spectroscopy (EELS) in an aberration corrected scanning transmission electron microscope (STEM). We show that the existence of grain boundaries (GBs) in these nanocavities results in shifts in the VP energy and a reduction in the VP lifetime. We map the VP energy and lifetime across GBs and we observe a decrease in VP energy and lifetime at GBs that is consistent with a reduction in free carrier density and increased plasmon scattering at these locations. Dipolar LSPR modes resonant in the UV and blue regions of the electromagnetic spectrum as well as higher-energy optically dark quadrupolar and hexapolar LSPR modes are also observed and mapped by STEM and EELS. All LSPR modes are confirmed via electromagnetic simulations based on the boundary element method. Both tetramer and hexamer structures support the excitation of dipolar bright and dipolar dark modes. Finally, we find that asymmetries in fabricated nanorod hexamer and tetramer nanocavities result in a mode mixing leading to a shift in dipolar dark LSPR modes.

8.
Opt Express ; 28(19): 27405-27414, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32988035

RESUMO

We theoretically investigated electron energy loss spectroscopy (EELS) of ultraviolet surface plasmon modes in aluminum nanodisks. Using full-wave Maxell electromagnetic simulations, we studied the impact of the diameter on the resonant modes of the nanodisks. We found that the mode behavior can be separately classified for two distinct cases: (1) flat nanodisks where the diameter is much larger than the thickness and (2) thick nanodisks where the diameter is comparable to the thickness. While the multipolar edge modes and breathing modes of flat nanostructures have previously been interpreted using intuitive, analytical models based on surface plasmon polariton (SPP) modes of a thin-film stack, it has been found that the true dispersion relation of the multipolar edge modes deviates significantly from the SPP dispersion relation. Here, we developed a modified intuitive model that uses effective wavelength theory to accurately model this dispersion relation with significantly less computational overhead compared to full-wave Maxwell electromagnetic simulations. However, for the case of thick nanodisks, this effective wavelength theory breaks down, and such intuitive models are no longer viable. We found that this is because some modes of the thick nanodisks carry a polar (i.e., out of the substrate plane or along the electron beam direction) dependence and cannot be simply categorized as radial breathing modes or angular (azimuthal) multipolar edge modes. This polar dependence leads to radiative losses, motivating the use of simultaneous EELS and cathodoluminescence measurements when experimentally investigating the complex mode behavior of thick nanostructures.

9.
Nanotechnology ; 31(4): 045302, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31578000

RESUMO

Targeted irradiation of nanostructures by a finely focused ion beam provides routes to improved control of material modification and understanding of the physics of interactions between ion beams and nanomaterials. Here, we studied radiation damage in crystalline diamond and silicon nanostructures using a focused helium ion beam, with the former exhibiting extremely long-range ion propagation and large plastic deformation in a process visibly analogous to blow forming. We report the dependence of damage morphology on material, geometry, and irradiation conditions (ion dose, ion energy, ion species, and location). We anticipate that our method and findings will not only improve the understanding of radiation damage in isolated nanostructures, but will also support the design of new engineering materials and devices for current and future applications in nanotechnology.

10.
Matern Child Health J ; 24(6): 679-686, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32277385

RESUMO

INTRODUCTION: Clinical experiences expose learners to the patient perspective, which can have a lasting impact on students' professional identity. However, in busy clinical settings where opportunities for reflection may be limited, listening to patients' stories is often neglected. We used a reflection assignment to augment a new maternal-child health integrated curriculum. METHODS: Medical students completed a brief assignment from their session in the neonatal intensive care unit (NICU), which included reflective writing, between fall 2016 and summer 2017. The Depth of Reflection rubric was used to score reflections on a scale: "Knowledge and Comprehension" (Level I), "Analysis" (Level II), and "Synthesis and Evaluation" (Level III). A constant comparison method based on grounded theory elicited prenatal and postnatal themes from medical students' reflective writing. RESULTS: All students completed narratives (n = 166); 70% (n = 116) achieved a Depth of Reflection of Level II or III. Six overarching themes emerged: (1) Conception, Pregnancy, and Delivery Experiences; (2) Positive Support Structures; (3) Barriers and Stressors to Care; (4) Future Plans; (5) Unexpected Complications; and (6) Student Career and Professional Considerations. DISCUSSION: Reflections from a novel and brief integrated maternal-child health experience demonstrated high levels on the Depth of Reflection scale. This experience exposed students to core themes central to a family's pregnancy and perinatal experience. Professional identity formation also emerged as a theme. Reflective writing assignments in a busy NICU can facilitate exploration of medical students' knowledge of maternal-child health patient experiences.


Assuntos
Atitude do Pessoal de Saúde , Saúde da Criança , Educação Médica/métodos , Saúde Materna , Estudantes de Medicina/psicologia , Feminino , Humanos , Gravidez , Redação
11.
Glob Chang Biol ; 25(10): 3215-3223, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31313869

RESUMO

The novel ecosystem (NE) concept has been discussed in terrestrial restoration ecology over the last 15 years but has not yet found much traction in the marine context. Against a background of unprecedented environmental change, managers of natural marine resources have portfolios full of altered systems for which restoration to a previous historical baseline may be impractical for ecological, social, or financial reasons. In these cases, the NE concept is useful for weighing options and emphasizes the risk of doing nothing by forcing questions regarding the value of novelty and how it can best be managed in the marine realm. Here, we explore how the concept fits marine ecosystems. We propose a scheme regarding how the NE concept could be used as a triage framework for use in marine environments within the context of a decision framework that explicitly considers changed ecosystems and whether restoration is the best or only option. We propose a conceptual diagram to show where marine NEs fit in the continuum of unaltered to shifted marine ecosystems. Overall, we suggest that the NE concept is of interest to marine ecologists and resource managers because it introduces a new vocabulary for considering marine systems that have been changed through human actions but have not shifted to an alternate stable state. Although it remains to be seen whether the concept of marine NEs leads to better conservation and restoration decisions, we posit that the concept may help inform management decisions in an era of unprecedented global marine change.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Ecologia , Atividades Humanas , Humanos , Triagem
12.
Opt Express ; 26(15): 18842-18854, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30114145

RESUMO

To achieve a feasible heat-assisted magnetic recording (HAMR) system, a near-field transducer (NFT) is necessary to strongly focus the optical field to a lateral region measuring tens of nanometres in size. An NFT must deliver sufficient power to the recording medium as well as maintain its structural integrity. The self-heating problem in the NFT causes materials failure that leads to the degradation of the hard disk drive performance. The literature reports NFT structures with physical sizes well below 1 micron which were found to be thermo-mechanically unstable at an elevated temperature. In this paper, we demonstrate an adiabatic NFT to address the central challenge of thermal engineering for a HAMR system. The NFT is formed by an isosceles triangular gold taper plasmonic waveguide with a length of 6 µm and a height of 50 nm. Our study shows that in the full optically and thermally optimized system, the NFT efficiently extracts the incident light from the waveguide core and can improve the shape of the heating source profile for data recording. The most important insight of the thermal performance is that the recording medium can be heated up to 866 K with an input power of 8.5 mW which is above the Curie temperature of the FePt film while maintaining the temperature in the NFT at 390 K without a heat spreader. A very good thermal efficiency of 5.91 is achieved also. The proposed structure is easily fabricated and can potentially reduce the NFT deformation at a high recording temperature making it suitable for practical HAMR application.

13.
Nanotechnology ; 29(27): 275301, 2018 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-29652671

RESUMO

Helium ion beam lithography (HIL) is an emerging nanofabrication technique. It benefits from a reduced interaction volume compared to that of an electron beam of similar energy, and hence reduced long-range scattering (proximity effect), higher resist sensitivity and potentially higher resolution. Furthermore, the small angular spread of the helium ion beam gives rise to a large depth of field. This should enable patterning on tilted and curved surfaces without the need of any additional adjustments, such as laser-auto focus. So far, most work on HIL has been focused on exploiting the reduced proximity effect to reach single-digit nanometer resolution, and has thus been concentrated on single-pixel exposures over small areas. Here we explore two new areas of application. Firstly, we investigate the proximity effect in large-area exposures and demonstrate HIL's capabilities in fabricating precise high-density gratings on large planar surfaces (100 µm × 100 µm, with pitch down to 35 nm) using an area dose for exposure. Secondly, we exploit the large depth of field by making the first HIL patterns on tilted surfaces (sample stage tilted 45°). We demonstrate a depth of field greater than 100 µm for a resolution of about 20 nm.

14.
Nano Lett ; 17(10): 6069-6076, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28926275

RESUMO

Understanding plasmon-mediated electron emission and energy transfer on the nanometer length scale is critical to controlling light-matter interactions at nanoscale dimensions. In a high-resolution lithographic material, electron emission and energy transfer lead to chemical transformations. In this work, we employ such chemical transformations in two different high-resolution electron-beam lithography resists, poly(methyl methacrylate) (PMMA) and hydrogen silsesquioxane (HSQ), to map local electron emission and energy transfer with nanometer resolution from plasmonic nanoantennas excited by femtosecond laser pulses. We observe exposure of the electron-beam resists (both PMMA and HSQ) in regions on the surface of nanoantennas where the local field is significantly enhanced. Exposure in these regions is consistent with previously reported optical-field-controlled electron emission from plasmonic hotspots as well as earlier work on low-electron-energy scanning probe lithography. For HSQ, in addition to exposure in hotspots, we observe resist exposure at the centers of rod-shaped nanoantennas in addition to exposure in plasmonic hotspots. Optical field enhancement is minimized at the center of nanorods suggesting that exposure in these regions involves a different mechanism to that in plasmonic hotspots. Our simulations suggest that exposure at the center of nanorods results from the emission of hot electrons produced via plasmon decay in the nanorods. Overall, the results presented in this work provide a means to map both optical-field-controlled electron emission and hot-electron transfer from nanoparticles via chemical transformations produced locally in lithographic materials.

15.
J Environ Manage ; 206: 446-457, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29107801

RESUMO

The extent of roads and other forms of linear infrastructure is burgeoning worldwide, but their impacts are inadequately understood and thus poorly mitigated. Previous studies have identified many potential impacts, including alterations to the hydrological functions and soil processes upon which ecosystems depend. However, these impacts have seldom been quantified at a regional level, particularly in arid and semi-arid systems where the gap in knowledge is the greatest, and impacts potentially the most severe. To explore the effects of extensive track, road, and rail networks on surface hydrology at a regional level we assessed over 1000 km of linear infrastructure, including approx. 300 locations where ephemeral streams crossed linear infrastructure, in the largely intact landscapes of Australia's Great Western Woodlands. We found a high level of association between linear infrastructure and altered surface hydrology, with erosion and pooling 5 and 6 times as likely to occur on-road than off-road on average (1.06 erosional and 0.69 pooling features km-1 on vehicle tracks, compared with 0.22 and 0.12 km-1, off-road, respectively). Erosion severity was greater in the presence of tracks, and 98% of crossings of ephemeral streamlines showed some evidence of impact on water movement (flow impedance (62%); diversion of flows (73%); flow concentration (76%); and/or channel initiation (31%)). Infrastructure type, pastoral land use, culvert presence, soil clay content and erodibility, mean annual rainfall, rainfall erosivity, topography and bare soil cover influenced the frequency and severity of these impacts. We conclude that linear infrastructure frequently affects ephemeral stream flows and intercepts natural overland and near-surface flows, artificially changing site-scale moisture regimes, with some parts of the landscape becoming abnormally wet and other parts becoming water-starved. In addition, linear infrastructure frequently triggers or exacerbates erosion, leading to soil loss and degradation. Where linear infrastructure densities are high, their impacts on ecological processes are likely to be considerable. Linear infrastructure is widespread across much of this relatively intact region, but there remain areas with very low infrastructure densities that need to be protected from further impacts. There is substantial scope for mitigating the impacts of existing and planned infrastructure developments.


Assuntos
Solo , Movimentos da Água , Austrália , Hidrologia , Rios
16.
Ecology ; 98(2): 500-511, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27864933

RESUMO

Understanding the relationship between plant diversity and diversity at higher trophic levels is important from both conservation and restoration perspectives. Although there is strong evidence for bottom-up maintenance of biodiversity, this is based largely on studies of simplified grassland systems. Recently, studies in the TreeDivNet global network of tree diversity experiments have begun to test whether these findings are generalizable to more complex ecosystems, such as woodlands. We monitored invertebrate community reassembly over 5 yr of experimental woodland restoration at the TreeDivNet Ridgefield site in southwest Australia, testing the effects of woody plant species richness and herb-layer manipulation on invertebrate community structure and ant species composition. From 2010 to 2014, we sampled ground-dwelling invertebrates using pitfall traps in herbicide vs. no-herbicide subplots nested within each of 10 woody plant treatments varying in richness from zero (bare controls) to eight species, which produced a total of 211, 235 invertebrates, including 98, 979 ants belonging to 74 species. In mixed model analyses, the presence of woody plants was an important driver of faunal community reassembly (relative to bare control plots), but faunal responses to woody plant treatment combinations were idiosyncratic and unrelated to woody plant richness across treatments. We also found that a herbicide-induced reduction in herbaceous plant cover and richness had a positive effect on ant richness and caused more rapid convergence of invertebrate community composition toward the composition of a woodland reference site. These findings show that woody plant richness did not have direct positive effects on the diversity and community reassembly trajectories of higher trophic levels in our woodland system. From a management perspective, this suggests that even low-diversity restoration or carbon sequestration plantings can potentially lead to faunal reassembly outcomes that are comparable to more complex re-planting designs.


Assuntos
Biodiversidade , Ecossistema , Invertebrados/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Animais , Austrália , Invertebrados/classificação , Árvores/classificação
17.
BMC Cardiovasc Disord ; 17(1): 58, 2017 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-28193176

RESUMO

BACKGROUND: Self-monitoring of hypertension is associated with lower systolic blood pressure (SBP). However, evidence for the use of self-monitoring to titrate antihypertensive medication by physicians is equivocal. Furthermore, there is some evidence for the efficacy of telemonitoring in the management of hypertension but it is not clear what this adds over and above self-monitoring. This trial aims to evaluate whether GP led antihypertensive titration using self-monitoring results in lower SBP compared to usual care and whether telemonitoring adds anything to self-monitoring alone. METHODS/DESIGN: This will be a pragmatic primary care based, unblinded, randomised controlled trial of self-monitoring of BP with or without telemonitoring compared to usual care. Eligible patients will have poorly controlled hypertension (>140/90 mmHg) and will be recruited from primary care. Participants will be individually randomised to either usual care, self-monitoring alone, or self-monitoring with telemonitoring. The primary outcome of the trial will be difference in clinic SBP between intervention and control groups at 12 months adjusted for baseline SBP, gender, BP target and practice. At least 1110 patients will be sufficient to detect a difference in SBP between self-monitoring with or without telemonitoring and usual care of 5 mmHg with 90% power with an adjusted alpha of 0.017 (2-sided) to adjust for all three pairwise comparisons. Other outcomes will include adherence of anti-hypertensive medication, lifestyle behaviours, health-related quality of life, and adverse events. An economic analysis will consider both within trial costs and a model extrapolating the results thereafter. A qualitative sub study will gain insights into the views, experiences and decision making processes of patients and health care professionals focusing on the acceptability of self-monitoring and telemonitoring in the routine management of hypertension. DISCUSSION: The results of the trial will be directly applicable to primary care in the UK. If successful, self-monitoring of BP in people with hypertension would be applicable to hundreds of thousands of individuals in the UK. TRIAL REGISTRATION: ISRCTN 83571366 . Registered 17 July 2014.


Assuntos
Determinação da Pressão Arterial/métodos , Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Hipertensão/diagnóstico , Telemedicina/métodos , Telemetria , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Protocolos Clínicos , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Valor Preditivo dos Testes , Atenção Primária à Saúde , Projetos de Pesquisa , Resultado do Tratamento , Reino Unido
18.
Nano Lett ; 16(7): 4149-57, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27295061

RESUMO

In this work, we use electron energy-loss spectroscopy to map the complete plasmonic spectrum of aluminum nanodisks with diameters ranging from 3 to 120 nm fabricated by high-resolution electron-beam lithography. Our nanopatterning approach allows us to produce localized surface plasmon resonances across a wide spectral range spanning 2-8 eV. Electromagnetic simulations using the finite element method support the existence of dipolar, quadrupolar, and hexapolar surface plasmon modes as well as centrosymmetric breathing modes depending on the location of the electron-beam excitation. In addition, we have developed an approach using nanolithography that is capable of meV control over the energy and attosecond control over the lifetime of volume plasmons in these nanodisks. The precise measurement of volume plasmon lifetime may also provide an opportunity to probe and control the DC electrical conductivity of highly confined metallic nanostructures. Lastly, we show the strong influence of the nanodisk boundary in determining both the energy and lifetime of surface plasmons and volume plasmons locally across individual aluminum nanodisks, and we have compared these observations to similar effects produced by scaling the nanodisk diameter.

19.
Ecol Appl ; 25(7): 1790-806, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26591446

RESUMO

State-and-transition models are increasingly used as a tool to inform management of post-disturbance succession and effective conservation of biodiversity in production landscapes. However, if they are to do this effectively, they need to represent faunal, as well as vegetation, succession. We assessed the congruence between vegetation and avian succession by sampling avian communities in each state of a state-and-transition model used to inform management of post-mining restoration in a production landscape in southwestern Australia. While avian communities differed significantly among states classified as on a desirable successional pathway, they did not differ between desirable and deviated states of the same post-mining age. Overall, we concluded there was poor congruence between vegetation and avian succession in this state-and-transition model. We identified four factors that likely contributed to this lack of congruence, which were that long-term monitoring of succession in restored mine pits was not used to update and improve models, states were not defined based on ecological processes and thresholds, states were not defined by criteria that were important in structuring the avian community, and states were not based on criteria that related to values in the reference community. We believe that consideration of these four factors in the development of state-and-transition models should improve their ability to accurately represent faunal, as well as vegetation, succession. Developing state-and-transition models that better incorporate patterns of faunal succession should improve the ability to manage post-disturbance succession across a range of ecosystems for biodiversity conservation.


Assuntos
Aves/fisiologia , Recuperação e Remediação Ambiental , Modelos Biológicos , Plantas/classificação , Animais , Aves/classificação , Monitoramento Ambiental , Mineração , Dinâmica Populacional
20.
Nano Lett ; 14(8): 4406-12, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-24960635

RESUMO

One challenge existing since the invention of electron-beam lithography (EBL) is understanding the exposure mechanisms that limit the resolution of EBL. To overcome this challenge, we need to understand the spatial distribution of energy density deposited in the resist, that is, the point-spread function (PSF). During EBL exposure, the processes of electron scattering, phonon, photon, plasmon, and electron emission in the resist are combined, which complicates the analysis of the EBL PSF. Here, we show the measurement of delocalized energy transfer in EBL exposure by using chromatic aberration-corrected energy-filtered transmission electron microscopy (EFTEM) at the sub-10 nm scale. We have defined the role of spot size, electron scattering, secondary electrons, and volume plasmons in the lithographic PSF by performing EFTEM, momentum-resolved electron energy loss spectroscopy (EELS), sub-10 nm EBL, and Monte Carlo simulations. We expect that these results will enable alternative ways to improve the resolution limit of EBL. Furthermore, our approach to study the resolution limits of EBL may be applied to other lithographic techniques where electrons also play a key role in resist exposure, such as ion-beam-, X-ray-, and extreme-ultraviolet lithography.

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