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1.
ACS Appl Mater Interfaces ; 16(28): 37275-37287, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38959130

RESUMO

Titanium dioxide (TiO2) shows significant potential as a self-cleaning material to inactivate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and prevent virus transmission. This study provides insights into the impact of UV-A light on the photocatalytic inactivation of adsorbed SARS-CoV-2 virus-like particles (VLPs) on a TiO2 surface at the molecular and atomic levels. X-ray photoelectron spectroscopy, combined with density functional theory calculations, reveals that spike proteins can adsorb on TiO2 predominantly via their amine and amide functional groups in their amino acids blocks. We employ atomic force microscopy and grazing-incidence small-angle X-ray scattering (GISAXS) to investigate the molecular-scale morphological changes during the inactivation of VLPs on TiO2 under light irradiation. Notably, in situ measurements reveal photoinduced morphological changes of VLPs, resulting in increased particle diameters. These results suggest that the denaturation of structural proteins induced by UV irradiation and oxidation of the virus structure through photocatalytic reactions can take place on the TiO2 surface. The in situ GISAXS measurements under an N2 atmosphere reveal that the virus morphology remains intact under UV light. This provides evidence that the presence of both oxygen and UV light is necessary to initiate photocatalytic reactions on the surface and subsequently inactivate the adsorbed viruses. The chemical insights into the virus inactivation process obtained in this study contribute significantly to the development of solid materials for the inactivation of enveloped viruses.


Assuntos
SARS-CoV-2 , Titânio , Raios Ultravioleta , Titânio/química , Titânio/efeitos da radiação , SARS-CoV-2/efeitos da radiação , SARS-CoV-2/química , Inativação de Vírus/efeitos da radiação , Inativação de Vírus/efeitos dos fármacos , Humanos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/virologia , COVID-19/prevenção & controle , Adsorção , Propriedades de Superfície
2.
NPJ Digit Med ; 7(1): 59, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499605

RESUMO

Type 1 diabetes (T1D) is a chronic condition characterized by glucose fluctuations. Laboratory studies suggest that cognition is reduced when glucose is very low (hypoglycemia) and very high (hyperglycemia). Until recently, technological limitations prevented researchers from understanding how naturally-occurring glucose fluctuations impact cognitive fluctuations. This study leveraged advances in continuous glucose monitoring (CGM) and cognitive ecological momentary assessment (EMA) to characterize dynamic, within-person associations between glucose and cognition in naturalistic environments. Using CGM and EMA, we obtained intensive longitudinal measurements of glucose and cognition (processing speed, sustained attention) in 200 adults with T1D. First, we used hierarchical Bayesian modeling to estimate dynamic, within-person associations between glucose and cognition. Consistent with laboratory studies, we hypothesized that cognitive performance would be reduced at low and high glucose, reflecting cognitive vulnerability to glucose fluctuations. Second, we used data-driven lasso regression to identify clinical characteristics that predicted individual differences in cognitive vulnerability to glucose fluctuations. Large glucose fluctuations were associated with slower and less accurate processing speed, although slight glucose elevations (relative to person-level means) were associated with faster processing speed. Glucose fluctuations were not related to sustained attention. Seven clinical characteristics predicted individual differences in cognitive vulnerability to glucose fluctuations: age, time in hypoglycemia, lifetime severe hypoglycemic events, microvascular complications, glucose variability, fatigue, and neck circumference. Results establish the impact of glucose on processing speed in naturalistic environments, suggest that minimizing glucose fluctuations is important for optimizing processing speed, and identify several clinical characteristics that may exacerbate cognitive vulnerability to glucose fluctuations.

3.
Public Health Nutr ; 27(1): e36, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38224164

RESUMO

OBJECTIVE: Diet quality is significantly impacted by social and environmental factors. People experiencing socio-economic disadvantage face inequitable barriers to accessing nutritious foods and health services, resulting in significant health disparities. This study aimed to explore the barriers faced by organisations that provide food support to people experiencing disadvantage as well as to identify potential strategies to enhance this support for improved well-being of clients. DESIGN: Semi-structured interviews using an exploratory approach and inductive thematic analysis. SETTING: Australia. PARTICIPANTS: Individuals from organisations involved in the provision of food support for people experiencing disadvantage aged ≥16 years. RESULTS: Two major themes were identified from thirteen interviews. 'Dignity and respect for clients' serves as a guiding principle for food-related services across all organisations, while 'food' was a point of connection and a potential gateway to additional support pathways. Five additional subthemes included 'food as a platform to reduce social isolation, foster connection and promote participation', challenges with 'servicing clients with diverse experiences and needs', 'dependence on staff and volunteers with varying knowledge and skillsets', ensuring 'adequate access to services, resources and facilities' and 'necessity of community collaboration'. CONCLUSIONS: This study highlights the unique position of organisations involved in food support to identify client-specific needs and implement broader holistic health support. Future interventions should prioritise dignity, respect and social connection in design. Organisations require an adequately trained, sustainable workforce, with shared or enhanced services, resources and facilities, and greater community coordination with other services to maximise effectiveness.


Assuntos
Alimentos , Estado Nutricional , Humanos , Austrália , Isolamento Social , Pesquisa Qualitativa
4.
J Environ Qual ; 52(4): 873-885, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37145888

RESUMO

Phosphorus (P) budgets can be useful tools for understanding nutrient cycling and quantifying the effectiveness of nutrient management planning and policies; however, uncertainties in agricultural nutrient budgets are not often quantitatively assessed. The objective of this study was to evaluate uncertainty in P fluxes (fertilizer/manure application, atmospheric deposition, irrigation, crop removal, surface runoff, and leachate) and the propagation of these uncertainties to annual P budgets. Data from 56 cropping systems in the P-FLUX database, which spans diverse rotations and landscapes across the United States and Canada, were evaluated. Results showed that across cropping systems, average annual P budget was 22.4 kg P ha-1 (range = -32.7 to 340.6 kg P ha-1 ), with an average uncertainty of 13.1 kg P ha-1 (range = 1.0-87.1 kg P ha-1 ). Fertilizer/manure application and crop removal were the largest P fluxes across cropping systems and, as a result, accounted for the largest fraction of uncertainty in annual budgets (61% and 37%, respectively). Remaining fluxes individually accounted for <2% of the budget uncertainty. Uncertainties were large enough that determining whether P was increasing, decreasing, or not changing was inconclusive in 39% of the budgets evaluated. Findings indicate that more careful and/or direct measurements of inputs, outputs, and stocks are needed. Recommendations for minimizing uncertainty in P budgets based on the results of the study were developed. Quantifying, communicating, and constraining uncertainty in budgets among production systems and multiple geographies is critical for engaging stakeholders, developing local and national strategies for P reduction, and informing policy.


Assuntos
Fertilizantes , Fósforo , Esterco , Incerteza , Agricultura
5.
Nanoscale ; 15(9): 4506-4514, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36753337

RESUMO

We demonstrate that oleyl phosphate ligand-stabilized iron oxide nanocubes as building blocks can be assembled into 2D supercrystalline mono- and multilayers on flat YSZ substrates within a few minutes using a simple spin-coating process. As a bottom-up process, the growth takes place in a layer-by-layer mode and therefore by tuning the spin-coating parameters, the exact number of deposited monolayers can be controlled. Furthermore, ex situ scanning electron and atomic force microscopy as well as X-ray reflectivity measurements give evidence that the choice of solvent allows the control of the lattice type of the final supercrystalline monolayers. This observation can be assigned to the different Hansen solubilities of the solvents used for the nanoparticle dispersion because it determines the size and morphology of the ligand shell surrounding the nanoparticle core. Here, by using toluene and chloroform as solvents, it can be controlled whether the resulting monolayers are ordered in a square or hexagonal supercrystalline lattice.

6.
AIDS Care ; 35(5): 719-728, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35277095

RESUMO

This study of people newly diagnosed of living with HIV (ND-PLHIV) calculated the use, cost and outcome of HIV services at a London HIV centre. ND-PLHIV were followed July 2017-October 2018. Hospital data included inpatient days (IP), outpatient (OP), dayward (DW) visits, tests and procedures, and anti-retroviral drugs (ARVs). Community services were recorded in daily diaries. Mean per patient-year (MPPY) use was multiplied by unit costs. 13.6 MPPY (95%CI 12.4-14.9) OP visits, 0.4 MPPY (95%CI 0.1-0.7) IP days, 0.09 MPPY (95%CI 0.01-0.2) DW visits and 4.6 MPPY community services (95%CI 3.4-5.8). Total annual costs per patient-year (CPPY) was £11,483 (95%CI £10,369-12,597): ARVs comprised 63% and community services 2%. White participants used fewer hospital and more community services compared with minority ethnic community (MEC) participants. Costs for White ND-PLHIV was £10,778 CPPY (95%CI £9629-11,928); £13,214 (95%CI £10,656-15,772) for MEC ND-PLHIV (p < 0.06). Annual costs were inversely related to CD4 count at entry (r = -5.58, p = 0.02); mean CD4 count was 476 cells/mm3 (95%CI 422-531) versus 373 cells/mm3 (95%CI 320-425) for White and MEC participants respectively (p = 0.03). Annual costs for ND-PLHIV with CD4 ≤ 350 cells/mm3 was £2478 PPY higher compared with CD4 count >350 cells/mm3 (p = 0.04).


Assuntos
Infecções por HIV , Humanos , Londres , Hospitais
7.
AIDS Care ; 35(6): 899-908, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35348411

RESUMO

This study estimated the efficiency of implementing the EmERGE Pathway of Care for people living with medically stable HIV in Brighton, UK; an App enables individuals to communicate with caregivers via their smart-phone. Individual data on the use of HIV outpatient services were collected one-year pre- and post-implementation of EmERGE. Unit costs of HIV outpatient services were calculated and linked with mean use of services per patient year. Primary outcomes were CD4 count and viral load; patient activation and quality-of-life measures were secondary outcomes. 565 participants were followed up April 2017 - October 2018: 93% men, mean age at recruitment 47.0 years (95%CI:46.2-47.8). Outpatient visits decreased by 9% from 5.6 (95%CI:5.4-5.8) to 5.1 (95%CI:4.9-5.3). Face-to-face visits decreased and virtual visits increased. Annual costs decreased by 9% from £751 (95%CI: £722-£780) to £678 (95%CI: £653-£705). Including anti-retroviral drugs, total annual cost decreased from £7,343 (95%CI: £7,314-7,372) to £7,270 (95%CI: £7,245-7,297): ARVs costs comprised 90%. EmERGE was a cost-saving intervention, patients remained engaged and clinically stable. Annual costs were reduced, but ARVs continue to dominate costs. Extension of EmERGE to other people with chronic conditions, could produce greater efficiencies but these needs to be evaluated and monitored over time.


Assuntos
Infecções por HIV , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Infecções por HIV/tratamento farmacológico , Custos de Cuidados de Saúde , Inglaterra , Assistência Ambulatorial
8.
Rev Sci Instrum ; 93(7): 073902, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35922329

RESUMO

A proof of concept is shown for the design of a high pressure heterogeneous catalysis reaction cell suitable for surface sensitive x-ray diffraction and x-ray reflectometry over planar samples using high energy synchrotron radiation in combination with mass spectrometry. This design enables measurements in a pressure range from several tens to hundreds of bars for surface investigations under realistic industrial conditions in heterogeneous catalysis or gaseous corrosion studies.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35906033

RESUMO

OBJECTIVE: Calculate the efficiency of the EmERGE Pathway of Care for medically stable people living with HIV at the Hospital Clínic-IDIBAPS, Barcelona, Spain. METHODS: 546 study participants were followed between 1st July 2016 and 30th October 2019 across three HIV outpatient clinics, but the virtual clinic was closed during the second year. Unit costs were calculated, linked to mean use outpatient services per patient year, one-year before and after the implementation of EmERGE. Costs were combined with primary and secondary outcomes. RESULTS: Annual costs across HIV-outpatient services increased by 8%: €1073 (95%CI €999-€1157) to €1158 (95%CI €1084-€1238). Annual cost of ARVs was €7,557; total annual costs increased by 1% from €8430 (95%CI €8356-8514) to €8515 (95%CI €8441-8595). Annual cost for 433 participants managed in face-to-face (F2F) clinics decreased by 5% from €958 (95%CI 905-1018) to €904 (95%CI 863-945); participants transferred from virtual to F2F outpatient clinics (V2F) increased their annual cost by a factor of 2.2, from €115 (95%CI 94-139) to €251 (95%CI 219-290). No substantive changes were observed in primary and secondary outcomes. CONCLUSION: EmERGE Pathway is an efficient and acceptable intervention. Increases in costs were caused by internal structural changes. The cost reduction observed in F2F clinics were off-set by the transfer of participants from the virtual to the F2F clinics due to the closure of the virtual clinic during the second year of the Study. Greater efficiencies are likely to be achieved by extending the use of the Pathway to other PLHIV.


Assuntos
Instituições de Assistência Ambulatorial , Infecções por HIV , Assistência Ambulatorial , Continuidade da Assistência ao Paciente , Infecções por HIV/terapia , Humanos , Espanha
10.
J Environ Qual ; 51(3): 451-461, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35373848

RESUMO

Quantifying spatial and temporal fluxes of phosphorus (P) within and among agricultural production systems is critical for sustaining agricultural production while minimizing environmental impacts. To better understand P fluxes in agricultural landscapes, P-FLUX, a detailed and harmonized dataset of P inputs, outputs, and budgets, as well as estimated uncertainties for each P flux and budget, was developed. Data were collected from 24 research sites and 61 production systems through the Long-term Agroecosystem Research (LTAR) network and partner organizations spanning 22 U.S. states and 2 Canadian provinces. The objectives of this paper are to (a) present and provide a description of the P-FLUX dataset, (b) provide summary analyses of the agricultural production systems included in the dataset and the variability in P inputs and outputs across systems, and (c) provide details for accessing the dataset, dataset limitations, and an example of future use. P-FLUX includes information on select site characteristics (area, soil series), crop rotation, P inputs (P application rate, source, timing, placement, P in irrigation water, atmospheric deposition), P outputs (crop removal, hydrologic losses), P budgets (agronomic budget, overall budget), uncertainties associated with each flux and budget, and data sources. Phosphorus fluxes and budgets vary across agricultural production systems and are useful resources to improve P use efficiency and develop management strategies to mitigate environmental impacts of agricultural systems. P-FLUX is available for download through the USDA Ag Data Commons (https://doi.org/10.15482/USDA.ADC/1523365).


Assuntos
Agricultura , Fósforo , Canadá , Fósforo/análise , Solo , Estados Unidos , Água
11.
Nat Commun ; 13(1): 1349, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292642

RESUMO

Speleothems can provide high-quality continuous records of the direction and relative paleointensity of the geomagnetic field, combining high precision dating (with U-Th method) and rapid lock-in of their detrital magnetic particles during calcite precipitation. Paleomagnetic results for a mid-to-late Holocene stalagmite from Dona Benedita Cave in central Brazil encompass ~1900 years (3410 BP to 5310 BP, constrained by 12 U-Th ages) of paleomagnetic record from 58 samples (resolution of ~33 years). This dataset reveals angular variations of less than 0.06° yr-1 and a relatively steady paleointensity record (after calibration with geomagnetic field model) contrasting with the fast variations observed in younger speleothems from the same region under influence of the South Atlantic Anomaly. These results point to a quiescent period of the geomagnetic field during the mid-to-late Holocene in the area now comprised by the South Atlantic Anomaly, suggesting an intermittent or an absent behavior at the multi-millennial timescale.

12.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33549335

RESUMO

OBJECTIVE: Calculate the efficiency of the EmERGE Pathway of Care for medically stable people living with HIV at the Hospital Clínic-IDIBAPS, Barcelona, Spain. METHODS: 546 study participants were followed between 1st July 2016 and 30th October 2019 across three HIV outpatient clinics, but the virtual clinic was closed during the second year. Unit costs were calculated, linked to mean use outpatient services per patient year, one-year before and after the implementation of EmERGE. Costs were combined with primary and secondary outcomes. RESULTS: Annual costs across HIV-outpatient services increased by 8%: €1073 (95%CI €999-€1157) to €1158 (95%CI €1084-€1238). Annual cost of ARVs was €7,557; total annual costs increased by 1% from €8430 (95%CI €8356-8514) to €8515 (95%CI €8441-8595). Annual cost for 433 participants managed in face-to-face (F2F) clinics decreased by 5% from €958 (95%CI 905-1018) to €904 (95%CI 863-945); participants transferred from virtual to F2F outpatient clinics (V2F) increased their annual cost by a factor of 2.2, from €115 (95%CI 94-139) to €251 (95%CI 219-290). No substantive changes were observed in primary and secondary outcomes. CONCLUSION: EmERGE Pathway is an efficient and acceptable intervention. Increases in costs were caused by internal structural changes. The cost reduction observed in F2F clinics were off-set by the transfer of participants from the virtual to the F2F clinics due to the closure of the virtual clinic during the second year of the Study. Greater efficiencies are likely to be achieved by extending the use of the Pathway to other PLHIV.

13.
Science ; 369(6510): 1497-1500, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32943524

RESUMO

Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary nebula (PN) could be due to binary interactions. We observed a sample of AGB stars with the Atacama Large Millimeter/submillimeter Array (ALMA) and found that their winds exhibit distinct nonspherical geometries with morphological similarities to planetary nebulae (PNe). We infer that the same physics shapes both AGB winds and PNe; additionally, the morphology and AGB mass-loss rate are correlated. These characteristics can be explained by binary interaction. We propose an evolutionary scenario for AGB morphologies that is consistent with observed phenomena in AGB stars and PNe.

14.
AJNR Am J Neuroradiol ; 41(9): 1569-1576, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32763897

RESUMO

BACKGROUND AND PURPOSE: Cellular uptake of the manganese ion, when administered as a contrast agent for MR imaging, can noninvasively highlight cellular activity and disease processes in both animals and humans. The purpose of this study was to explore the enhancement profile of manganese in patients with multiple sclerosis. MATERIALS AND METHODS: Mangafodipir is a manganese chelate that was clinically approved for MR imaging of liver lesions. We present a case series of 6 adults with multiple sclerosis who were scanned at baseline with gadolinium, then injected with mangafodipir, and followed at variable time points thereafter. RESULTS: Fourteen new lesions formed during or shortly before the study, of which 10 demonstrated manganese enhancement of varying intensity, timing, and spatial pattern. One gadolinium-enhancing extra-axial mass, presumably a meningioma, also demonstrated enhancement with manganese. Most interesting, manganese enhancement was detected in lesions that formed in the days after mangafodipir injection, and this enhancement persisted for several weeks, consistent with contrast coming from intracellular uptake of manganese. Some lesions demonstrated a diffuse pattern of manganese enhancement in an area larger than that of both gadolinium enhancement and T2-FLAIR signal abnormality. CONCLUSIONS: This work demonstrates the first use of a manganese-based contrast agent to enhance MS lesions on MR imaging. Multiple sclerosis lesions were enhanced with a temporal and spatial profile distinct from that of gadolinium. Further experiments are necessary to uncover the mechanism of manganese contrast enhancement as well as cell-specific uptake.


Assuntos
Meios de Contraste/administração & dosagem , Ácido Edético/análogos & derivados , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Fosfato de Piridoxal/análogos & derivados , Adulto , Animais , Ácido Edético/administração & dosagem , Feminino , Humanos , Injeções Intravenosas , Masculino , Esclerose Múltipla/patologia , Projetos Piloto , Fosfato de Piridoxal/administração & dosagem
15.
BJOG ; 126(13): 1560-1567, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31310697

RESUMO

OBJECTIVE: Risk of fetotoxicity after paracetamol exposure in the third trimester. DESIGN: Observational cohort study and retrospective case assessment. SETTING: Germany, 2008-2017. POPULATION: Pregnant women exposed to paracetamol. METHODS: Prospectively enrolled third-trimester pregnancies that had been exposed to paracetamol (604) were compared with pregnancies exposed to paracetamol in the first and/or second trimester only (1192). Exclusion criteria were exposure to nonsteroidal anti-inflammatory drugs (NSAIDs) in the second or third trimester. Additionally, the Embryotox 'adverse drug reaction in pregnancy' database was screened for cases of fetotoxicity. MAIN OUTCOME MEASURES: The prenatal study end points focused on narrowing or closure of ductus arteriosus Botalli, late fetal death, and oligohydramnios. The postnatal end points included patent ductus arteriosus (PDA), primary pulmonary hypertension (PPHT), and impaired renal function. RESULTS: In both cohorts, no fetus with intrauterine narrowing or closure of the ductus arteriosus Botalli was reported (0/604 versus 0/1192). Oligohydramnios was diagnosed at a similar frequency in both cohorts: 1.3% (8/604) versus 1.6% (19/1192). There was one stillbirth in the study cohort (1/604, 0.2%) and four stillbirths in the comparison cohort (4/1192, 0.3%). The rates of PDA in neonates were similar: 0.7% (4/615) versus 0.7% (9/1212). PPHT as well as serious postnatal renal disorders were reported once in each cohort. In 12 out of 96 retrospective cases, there were indicators for study end points; however, co-exposure to NSAIDs or complex situations weaken the assumption of paracetamol toxicity. CONCLUSIONS: Fetal cardiovascular or renal toxicity of maternal third-trimester paracetamol use appears to be negligible. TWEETABLE ABSTRACT: Paracetamol use in the third trimester does not seem to be associated with a relevant risk of fetotoxicity.


Assuntos
Acetaminofen/administração & dosagem , Analgésicos não Narcóticos/administração & dosagem , Permeabilidade do Canal Arterial/induzido quimicamente , Nefropatias/induzido quimicamente , Rim/efeitos dos fármacos , Acetaminofen/efeitos adversos , Adulto , Analgésicos não Narcóticos/efeitos adversos , Permeabilidade do Canal Arterial/embriologia , Feminino , Humanos , Recém-Nascido , Rim/anormalidades , Rim/embriologia , Nefropatias/embriologia , Gravidez , Terceiro Trimestre da Gravidez , Estudos Retrospectivos , Medição de Risco
16.
Soc Sci Res ; 73: 13-30, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29793682

RESUMO

The Great Migration and the Civil Rights Movement were two pivotal events experienced by the southern African American population during the 20th Century. Each has received considerable attention by social scientists and historians, and a possible connection between the two phenomena has been speculated. However, no systematic investigation of the effect of migration on protest during the Jim Crow era has been conducted. In this study we use data for 333 southern communities to examine the relationship between youthful black migration between 1950 and 1960 and the occurrence of sit-ins early in 1960. We find a strong positive, non-linear, relationship between net-migration and the likelihood of a sit-in which can be explained by two sets of mediating influences: local demographic conditions and local organizational presence. Our findings offer strong empirical support for an association between southern black migration and protest during Jim Crow and suggest the value of considering the influence of demographic forces on collective action.

17.
AJNR Am J Neuroradiol ; 39(3): 459-466, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29439120

RESUMO

BACKGROUND AND PURPOSE: Cortical lesions are common and often extensive in multiple sclerosis but are difficult to visualize by MRI, leaving important questions about their clinical implications and response to therapy unanswered. Our aim was to determine whether cortical lesions are better visualized using magnetization prepared 2 rapid acquisition gradient echoes (MP2RAGE) than T2*-weighted imaging on 7T MR imaging. MATERIALS AND METHODS: Brain MR imaging using T1-weighted MP2RAGE at 500-µm isotropic resolution, T2*-weighted gradient-echo, and T2*-weighted segmented echo-planar imaging sequences were collected for 13 patients with MS and 5 age-matched neurologically healthy controls on a 7T research system. One MS case underwent postmortem MR imaging including gradient-echo and MP2RAGE sequences, after which cortical lesions seen on MR imaging were assessed with immunohistochemistry. RESULTS: MP2RAGE detected 203 cortical lesions (median, 16 lesions/case; interquartile range, 15), compared to 92 with T2*gradient-echo (median, 7; interquartile range, 8; P < .001) and 81 with T2*EPI (median, 7; interquartile range, 5; P < .001). This increase in lesion number detected on MP2RAGE versus T2* was observed for juxtacortical, leukocortical, and intracortical lesions. Forty-three percent of all cortical lesions were identified only on MP2RAGE. White matter lesion volume correlated with total juxtacortical (r = 0.86, P < .001) and leukocortical lesion volume (r = 0.70, P < .01) but not intracortical lesion volume, suggesting that pathophysiology may differ by lesion type. Of 4 suspected lesions seen on postmortem imaging, 3 were found to be true cortical lesions while 1 represented postmortem tissue damage. CONCLUSIONS: A combination of MP2RAGE and T2*-weighted imaging at 7T improved detection of cortical lesions and should enable longitudinal studies to elucidate their spatiotemporal dynamics and clinical implications.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Neuroimagem/métodos , Adulto , Córtex Cerebral/patologia , Imagem Ecoplanar/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
18.
J Hum Nutr Diet ; 31(4): 573-583, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29473238

RESUMO

BACKGROUND: The present study aimed to determine the eHealth readiness and changes over time of dietitians in Australia. METHODS: Two cross-sectional analyses of Australian dietitians were conducted in 2013 and 2016, using a survey adapted from one conducted in 2011 by the US Academy of Nutrition and Dietetics. The survey encompassed 30 questions on eHealth readiness across five dimensions: access, standards, attitude, aptitude and advocacy. Descriptive statistics, independent t-tests, chi-squared tests and Z-tests were computed to compare responses from the 2013 and 2016 surveys. RESULTS: The survey completion rate represented 14.5% (747) of the Dietitians Association of Australia members in 2013 and 8% (417) in 2016. The survey responses in relation to access and standards suggest that dietitians are well positioned for eHealth. For attitude and aptitude, there is a moderate level of preparedness, with minor improvements over time. Although showing significant improvement (P < 0.05), advocacy highlights the area requiring the most development because the majority of dietitians (61%) reported 'no role' in eHealth solutions. CONCLUSIONS: Dietitians are progressing in relation to access, attitudinal and aptitudinal readiness for eHealth, although they rate poorly with respect to advocacy readiness. It was concluded that dietitians are not yet ready, and also that valuable opportunities to achieve the benefits that eHealth can deliver will be missed, if dietitians do not take the lead in guiding the development, selection and implementation of nutrition-related technologies. Strengthening the dimension of advocacy and ensuring collaboration across the profession, drawing on the varying expertise demonstrated across the practice areas and by the different generations, will be central to improving dietitian eHealth readiness.


Assuntos
Nutricionistas/estatística & dados numéricos , Nutricionistas/tendências , Telemedicina/estatística & dados numéricos , Telemedicina/tendências , Adulto , Idoso , Aptidão , Atitude do Pessoal de Saúde , Austrália , Estudos Transversais , Dietética/estatística & dados numéricos , Dietética/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
19.
J Hum Nutr Diet ; 31(1): 41-46, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28730664

RESUMO

BACKGROUND: Assessment presents one of the greatest challenges to evaluating health professional trainee performance, as a result of the subjectivity of judgements and variability in assessor standards. The present study aimed to test a moderation procedure for assessment across four independent universities and explore approaches to assessment and the factors that influence assessment decisions. METHODS: Assessment tasks designed independently by each of the four universities to assess student readiness for placement were chosen for the present study. Each university provided four student performance recordings for moderation. Eight different academic assessors viewed the student performances and assessed them using the corresponding university assessment instrument. Assessment results were collated and presented back to the assessors, together with the original university assessment results. Results were discussed with assessors to explore variations. The discussion was recorded, transcribed, thematically analysed and presented back to all assessors to achieve consensus on the emerging major learnings. RESULTS: Although there were differences in absolute scores, there was consistency (12 out of 16 performances) in overall judgement decisions regarding placement readiness. Proficient communication skills were considered a key factor when determining placement readiness. The discussion revealed: (i) assessment instruments; (ii) assessor factors; and (iii) the subjectivity of judgement as the major factors influencing assessment. CONCLUSIONS: Assessment moderation is a useful method for improving the quality of assessment decisions by sharing understanding and aligning standards of performance.


Assuntos
Competência Clínica , Tomada de Decisões , Dietética/educação , Educação Profissionalizante , Avaliação Educacional/métodos , Nutricionistas/educação , Universidades , Comunicação , Emprego , Humanos , Julgamento , Competência Profissional , Estudantes
20.
Astron Astrophys ; 6052017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-29142327

RESUMO

CONTEXT: Recent observations at subarcsecond resolution, now possible also at submillimeter wavelengths, have shown intricate circumstellar structures around asymptotic giant branch (AGB) stars, mostly attributed to binary interaction. The results presented here are part of a larger project aimed at investigating the effects of a binary companion on the morphology of circumstellar envelopes (CSEs) of AGB stars. AIMS: AGB stars are characterized by intense stellar winds that build CSEs around the stars. Here, the CO(J = 3→2) emission from the CSE of the binary S-type AGB star W Aql has been observed at subarcsecond resolution using ALMA. The aim of this paper is to investigate the wind properties of the AGB star and to analyse how the known companion has shaped the CSE. METHODS: The average mass-loss rate during the creation of the detected CSE is estimated through modelling, using the ALMA brightness distribution and previously published single-dish measurements as observational constraints. The ALMA observations are presented and compared to the results from a 3D smoothed particle hydrodynamics (SPH) binary interaction model with the same properties as the W Aql system and with two different orbital eccentricities. Three-dimensional radiative transfer modelling is performed and the response of the interferometer is modelled and discussed. RESULTS: The estimated average mass-loss rate of W Aql is M = 3.0×10-6 M⊙ yr-1 and agrees with previous results based on single-dish CO line emission observations. The size of the emitting region is consistent with photodissociation models. The inner 10″ of the CSE is asymmetric with arc-like structures at separations of 2-3″ scattered across the denser sections. Further out, weaker spiral structures at greater separations are found, but this is at the limit of the sensitivity and field of view of the ALMA observations. CONCLUSIONS: The CO(J = 3→2) emission is dominated by a smooth component overlayed with two weak arc patterns with different separations. The larger pattern is predicted by the binary interaction model with separations of ~10″ and therefore likely due to the known companion. It is consistent with a binary orbit with low eccentricity. The smaller separation pattern is asymmetric and coincides with the dust distribution, but the separation timescale (200 yrs) is not consistent with any known process of the system. The separation of the known companions of the system is large enough to not have a very strong effect on the circumstellar morphology. The density contrast across the envelope of a binary with an even larger separation will not be easily detectable, even with ALMA, unless the orbit is strongly asymmetric or the AGB star has a much larger mass-loss rate.

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