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1.
medRxiv ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38712274

RESUMO

Introduction: Racial/ethnic disparities in maternal mortality rates represent one of the most significant areas of disparities amongst all conventional population perinatal health measures in the U.S. The alarming trends and persistent disparities of outcomes by race/ethnicity and geographic location reinforce the need to focus on ensuring quality and safety of maternity care for all women. Despite complex multilevel factors impacting maternal mortality and morbidity, there are evidence-based interventions that, when facilitated consistently and properly, are known to improve the health of mothers before, during and after pregnancy. The objective of this project is to test implementation of pre-conception counseling with father involvement in community-based settings to improve cardiovascular health outcomes before and during pregnancy in southeastern United States. Methods and Analysis: This study has two components: a comprehensive needs and assets assessment and a small-scale pilot study. We will conduct a community informed needs and assets assessment with our diverse stakeholders to identify opportunities and barriers to preconception counseling as well as develop a stakeholder-informed implementation plan. Next, we will use the implementation plan to pilot preconception counseling with father involvement in community-based settings. Finally, we will critically assess the context, identify potential barriers and facilitators, and iteratively adapt the way preconception counseling can be implemented in diverse settings. Results of this research will support future research focused on identifying barriers and opportunities for scalable and sustainable public health approaches to implementing evidence-based strategies that reduce maternal morbidity and mortality in the southeastern United States' vulnerable communities. Discussion: Findings will demonstrate that preconception counseling can be implemented in community health settings in the southeastern United States. Furthermore, this study will build the capacity of community-based organizations in addressing the preconception health of their clients. We plan for this pilot to inform a larger scaled-up clinical trial across community health settings in multiple southeastern states.

2.
J Neonatal Perinatal Med ; 16(4): 589-596, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38007677

RESUMO

OBJECTIVE: We sought to investigate the clinical determinants of intestinal failure and death in preterm infants with surgical NEC. METHODS: Retrospective comparison of clinical information between Group A = intestinal failure (Parenteral nutrition (PN) >90 days) and death and Group B = survivors and with PN dependence < 90 days in preterm infants with surgical NEC. RESULTS: Group A (n = 99/143) had a lower mean gestational age (26.4 weeks [SD3.5] vs. 29.4 [SD 3.5]; p = 0.013), lower birth weight (873 gm [SD 427g] vs. 1425 gm [894g]; p = <0.001), later age of NEC onset (22 days [SD20] vs. 16 days [SD 17]; p = 0.128), received surgery later (276 hours [SD 544] vs. 117 hours [SD 267]; p = 0.032), had cholestasis, received dopamine (80.6% vs. 58.5%; p = 0.010) more frequently and had longer postoperative ileus time (19.8 days [SD 15.4] vs. 11.8 days [SD 6.5]; p = <0.001) and reached full feeds later (93 days [SD 45] vs. 44 [SD 22]; p = <0.001) than Group B.On multivariate logistic regression, higher birth weight was associated with lower risk (OR 0.35, 95% CI 0.15-0.82; p = 0.016) of TPN > 90 days or death. Longer length of bowel resected (OR 1.76, 95% CI 1.02-3.02; p = 0.039) and longer postoperative ileus (OR 2.87, 95% CI 1.26-6.53; p = 0.011) were also independently associated with TPN >90days or death adjusted for gestational age and antenatal steroid treatment. CONCLUSION: In preterm infants with surgical NEC, clinical factors such as lower birth weight, longer bowel loss, and postoperative ileus days were significantly and independently associated with TPN >90 days or death.


Assuntos
Enterocolite Necrosante , Íleus , Doenças do Recém-Nascido , Insuficiência Intestinal , Gravidez , Lactente , Recém-Nascido , Feminino , Humanos , Recém-Nascido Prematuro , Peso ao Nascer , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/cirurgia , Estudos Retrospectivos , Íleus/epidemiologia
3.
Surg Radiol Anat ; 45(5): 611-622, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36912942

RESUMO

PURPOSE: The tarsal tunnel (TT) is a fibro-osseous anatomical space coursing from the medial ankle to the medial midfoot. This tunnel acts as a passage for both tendinous and neurovascular structures, including the neurovascular bundle containing the posterior tibial artery (PTA), posterior tibial veins (PTVs) and tibial nerve (TN). Tarsal tunnel syndrome (TTS) is the entrapment neuropathy that describes the compression and irritation of the TN within this space. Iatrogenic injury to the PTA plays a significant role in both the onset and exacerbation of TTS symptoms. The current study aims to produce a method to allow clinicians and surgeons to easily and accurately predict the bifurcation of the PTA, to avoid iatrogenic injury during treatment of TTS. METHODS: Fifteen embalmed cadaveric lower limbs were dissected at the medial ankle region to expose the TT. Various measurements regarding the location of the PTA within the TT were recorded and multiple linear regression analysis performed using RStudio. RESULTS: Analysis provided a clear correlation (p < 0.05) between the length of the foot (MH), length of hind-foot (MC) and location of bifurcation of the PTA (MB). Using these measurements, this study developed an equation (MB = 0.3*MH + 0.37*MC - 28.24 mm) to predict the location of bifurcation of the PTA within a 23° arc inferior to the medial malleolus. CONCLUSIONS: This study successfully developed a method whereby clinicians and surgeons can easily and accurately predict the bifurcation of the PTA, to avoid iatrogenic injury that would previously lead to an exacerbation of TTS symptoms.


Assuntos
Síndrome do Túnel do Tarso , Artérias da Tíbia , Humanos , Síndrome do Túnel do Tarso/etiologia , Síndrome do Túnel do Tarso/cirurgia , Nervo Tibial , Tornozelo , Doença Iatrogênica/prevenção & controle
4.
Eur Phys J Plus ; 137(8): 924, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35990376

RESUMO

During the COVID-19 pandemic, members of the DarkSide-20k (DS) Dark Matter international experimental collaboration together with engineers, scientists and manufacturers in Italy, Canada, the USA and eight other countries diverted their research efforts to develop MVM, a new readily manufactured, relatively low-cost ventilator tailored to the most severe intubated patients. Using expertise developed for DS, they produced and received authorization for 7300 units delivered to the Canadian government for its stockpile, now being considered for donation to other countries in urgent need. Other members of DS are using photo-electronics innovation to develop 3D π a more sensitive positron emission tomography (PET) scanner that can provide better resolution and reduce doses, of particular value for providing access for pediatric patients.

5.
Rev Sci Instrum ; 93(5): 053103, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35649763

RESUMO

This paper describes the development of a pulsed light source using the discharge from an electrode in a medium of various noble gases. This source can be used to aid in the characterization and testing of new vacuum-ultraviolet sensitive light detection devices. The source includes a novel spark driver circuit, a spark chamber into which different noble gases can be introduced, and an optical attenuation cell capable of being filled with different gases to allow for the attenuation of the pulsed light down to single photon levels. We describe the construction, calibration, and characterization of this device deployed at a dedicated light detection test stand at Oak Ridge National Laboratory.

6.
Sci Total Environ ; 838(Pt 2): 156019, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35595131

RESUMO

Trees in natural and managed environments can act as conduits for the transportation of methane (CH4) from below ground to the atmosphere, bypassing oxidation in aerobic surface soils. Tree stem emissions from landfill sites exhibit large temporal and spatial variability in temperate environments and can account for approximately 40% of the total surface CH4 flux. Emission variability was further investigated in this study by measuring CH4 and CO2 fluxes from landfill sites with different management strategies and varying tree species over a 7-month period. Stem and soil measurements were obtained using flux chambers and an off-axis integrated cavity output spectroscopy analyser. Analysis showed average stem and soil CH4 emissions varied significantly (p < 0.01) between landfills with different management practices. On average, tree stem CH4 fluxes from sites with no clay cap but gas extraction, clay cap and gas extraction, and no clay cap and no gas extraction were 1.4 ± 0.4 µg m-2 h-1, 47.2 ± 19.0 µg m-2 h-1, and 111.9 ± 165.1 µg m-2 h-1, respectively. There was no difference in stem CH4 fluxes between species at each site, suggesting environmental conditions (waterlogging) and site age had a greater influence on both stem and soil fluxes. These results highlight the importance of management practices, and the resultant environmental conditions, in determining CH4 emissions from historic landfill sites.


Assuntos
Metano , Eliminação de Resíduos , Florestas , Metano/análise , Solo , Árvores , Instalações de Eliminação de Resíduos
7.
Phys Rev Lett ; 128(3): 033602, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35119876

RESUMO

We demonstrate how the presence of continuous weak symmetry can be used to analytically diagonalize the Liouvillian of a class of Markovian dissipative systems with strong interactions or nonlinearity. This enables an exact description of the full dynamics and dissipative spectrum. Our method can be viewed as implementing an exact, sector-dependent mean-field decoupling, or alternatively, as a kind of quantum-to-classical mapping. We focus on two canonical examples: a nonlinear bosonic mode subject to incoherent loss and pumping, and an inhomogeneous quantum Ising model with arbitrary connectivity and local dissipation. In both cases, we calculate and analyze the full dissipation spectrum. Our method is applicable to a variety of other systems, and could provide a powerful new tool for the study of complex driven-dissipative quantum systems.

8.
Geoderma ; 405: 115396, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34980929

RESUMO

A crucial decision in designing a spatial sample for soil survey is the number of sampling locations required to answer, with sufficient accuracy and precision, the questions posed by decision makers at different levels of geographic aggregation. In the Indian Soil Health Card (SHC) scheme, many thousands of locations are sampled per district. In this paper the SHC data are used to estimate the mean of a soil property within a defined study area, e.g., a district, or the areal fraction of the study area where some condition is satisfied, e.g., exceedence of a critical level. The central question is whether this large sample size is needed for this aim. The sample size required for a given maximum length of a confidence interval can be computed with formulas from classical sampling theory, using a prior estimate of the variance of the property of interest within the study area. Similarly, for the areal fraction a prior estimate of this fraction is required. In practice we are uncertain about these prior estimates, and our uncertainty is not accounted for in classical sample size determination (SSD). This deficiency can be overcome with a Bayesian approach, in which the prior estimate of the variance or areal fraction is replaced by a prior distribution. Once new data from the sample are available, this prior distribution is updated to a posterior distribution using Bayes' rule. The apparent problem with a Bayesian approach prior to a sampling campaign is that the data are not yet available. This dilemma can be solved by computing, for a given sample size, the predictive distribution of the data, given a prior distribution on the population and design parameter. Thus we do not have a single vector with data values, but a finite or infinite set of possible data vectors. As a consequence, we have as many posterior distribution functions as we have data vectors. This leads to a probability distribution of lengths or coverages of Bayesian credible intervals, from which various criteria for SSD can be derived. Besides the fully Bayesian approach, a mixed Bayesian-likelihood approach for SSD is available. This is of interest when, after the data have been collected, we prefer to estimate the mean from these data only, using the frequentist approach, ignoring the prior distribution. The fully Bayesian and mixed Bayesian-likelihood approach are illustrated for estimating the mean of log-transformed Zn and the areal fraction with Zn-deficiency, defined as Zn concentration <0.9 mg kg -1, in the thirteen districts of Andhra Pradesh state. The SHC data from 2015-2017 are used to derive prior distributions. For all districts the Bayesian and mixed Bayesian-likelihood sample sizes are much smaller than the current sample sizes. The hyperparameters of the prior distributions have a strong effect on the sample sizes. We discuss methods to deal with this. Even at the mandal (sub-district) level the sample size can almost always be reduced substantially. Clearly SHC over-sampled, and here we show how to reduce the effort while still providing information required for decision-making. R scripts for SSD are provided as supplementary material.

9.
Opt Express ; 29(20): 31941-31951, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615275

RESUMO

Light-sheet fluorescence microscopy has greatly improved the speed and overall photostability of optically sectioning cellular and multi-cellular specimens. Similar gains have also been conferred by light-sheet Raman imaging; these schemes, however, rely on diffraction limited Gaussian beams that hinder the uniformity and size of the imaging field-of-view, and, as such, the resulting throughput rates. Here, we demonstrate that a digitally scanned Airy beam increases the Raman imaging throughput rates by more than an order of magnitude than conventional diffraction-limited beams. Overall, this, spectrometer-less, approach enabled 3D imaging of microparticles with high contrast and 1 µm axial resolution at 300 msec integration times per plane and orders of magnitude lower irradiation density than coherent Raman imaging schemes. We detail the apparatus and its performance, as well as its compatibility with fluorescence light-sheet and quantitative-phase imaging towards rapid and low phototoxicity multimodal imaging.


Assuntos
Aumento da Imagem/métodos , Iluminação/métodos , Microscopia/métodos , Análise Espectral Raman/métodos , Dimetilpolisiloxanos , Microscopia de Fluorescência/métodos
10.
Clin Oncol (R Coll Radiol) ; 33(1): e22-e30, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32709540

RESUMO

AIMS: The incidence of anal squamous cell cancer (SCCA) is rising. Although chemoradiotherapy (CRT) provides a chance of cure, a proportion of patients have an incomplete response or develop recurrence. This study assessed the value of inflammation-based prognostic indicators, including the modified Glasgow Prognostic Score (mGPS) and neutrophil:lymphocyte ratio (NLR), in patients with SCCA treated by CRT with curative intent. MATERIAL AND METHODS: Patients with histologically confirmed SCCA were identified from pathology records. Medical records were retrospectively reviewed and clinical, pathological and treatment characteristics were abstracted. The mGPS (0 = normal C-reactive protein [CRP] and albumin, 1 = CRP >10 mg/l and 2 = CRP >10 mg/l and albumin <35 mg/l) and NLR were calculated from routine blood tests obtained prior to CRT. RESULTS: In total, 118 patients underwent CRT for SCCA between December 2007 and February 2018. Of these, 99 patients had appropriate pretreatment blood results available. Systemic inflammation as indicated by NLR >3 and mGPS >0 was present in 41% and 39% of patients, respectively. Most patients had T2 or larger tumours (n = 85, 86%) without nodal involvement (n = 64, 65%). An elevated mGPS was associated with more advanced T-stage (56% versus 35%, P = 0.036). NLR >5 was associated with nodal positivity (56% versus 31%, P = 0.047). On multivariate analysis, more advanced T-stage (odds ratio 7.49, 95% confidence interval 1.51-37.20, P = 0.014) and a raised mGPS (odds ratio 5.13, 95% confidence interval 1.25-21.14, P = 0.024) were independently related to incomplete CRT response. An elevated mGPS was prognostic of inferior survival (hazard ratio 3.09, 95% confidence interval 1.47-6.50, P = 0.003) and cancer-specific survival (hazard ratio 4.32, 95% confidence interval 1.54-12.15, P = 0.006), independent of TNM stage. CONCLUSION: Systemic inflammation, as measured by the mGPS, is associated with an incomplete CRT response and is independently prognostic of inferior survival in patients with SCCA. The mGPS may offer a simple marker of inferior outcome that could be used to identify high-risk patients.


Assuntos
Neoplasias do Ânus , Carcinoma de Células Escamosas , Quimiorradioterapia/métodos , Inflamação/sangue , Linfócitos , Neutrófilos , Neoplasias do Ânus/imunologia , Neoplasias do Ânus/patologia , Neoplasias do Ânus/terapia , Proteína C-Reativa/análise , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
11.
J Therm Spray Technol ; 30(1-2): 145-156, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-38624489

RESUMO

Metallization of polyethylene (PE) using thermal spray techniques has proved difficult due to its low melting point and softness. In this study, metallic coatings were applied on porous polyethylene substrates using a twin wire-arc spray process. Commercially available polyethylene sheets, 3 mm in thickness, were used as substrates. Copper (Cu), aluminum (Al), and zinc (Zn) were successfully deposited on the porous polymer, without prior surface preparation, to form coatings with thickness of about 400 µm. Coating surface morphology and cross-sections were examined using a scanning electron microscope. Individual metal splats on the porous and non-porous substrates were observed to study the differences in the bonding mechanisms. The adhesion strength and electrical resistivity of the coatings on porous PE were evaluated. It was found that the bond strength of all three metallic coatings was found to be higher than the ultimate fracture strength of the porous. These results suggest that porosity in the polymer helps to overcome the challenges of metallizing polyethylene and provides a significant reduction in the weight of the polymer. Therefore, all these properties aided in fabricating an extremely lightweight, composite material with potential use in thermal management applications.

12.
Agric Syst ; 185: 102954, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32982021

RESUMO

To contain the COVID-19 pandemic, India imposed a national lockdown at the end of March 2020, a decision that resulted in a massive reverse migration as many workers across economic sectors returned to their home regions. Migrants provide the foundations of the agricultural workforce in the 'breadbasket' states of Punjab and Haryana in Northwest India.There are mounting concerns that near and potentially longer-term reductions in labor availability may jeopardize agricultural production and consequently national food security. The timing of rice transplanting at the beginning of the summer monsoon season has a cascading influence on productivity of the entire rice-wheat cropping system. To assess the potential for COVID-related reductions in the agriculture workforce to disrupt production of the dominant rice-wheat cropping pattern in these states, we use a spatial ex ante modelling framework to evaluate four scenarios representing a range of plausible labor constraints on the timing of rice transplanting. Averaged over both states, results suggest that rice productivity losses under all delay scenarios would be low as compare to those for wheat, with total system productivity loss estimates ranging from 9%, to 21%, equivalent to economic losses of USD $674 m to $1.48 billion. Late rice transplanting and harvesting can also aggravate winter air pollution with concomitant health risks. Technological options such as direct seeded rice, staggered nursery transplanting, and crop diversification away from rice can help address these challenges but require new approaches to policy and incentives for change.

13.
World Dev ; 135: 105064, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32834377

RESUMO

Emerging evidence supports the intuitive link between chronic health conditions associated with air pollution and the vulnerability of individuals and communities to COVID-19. Poor air quality already imposes a highly significant public health burden in Northwest India, with pollution levels spiking to hazardous levels in November and early December when rice crop residues are burned. The urgency of curtailing the COVID-19 pandemic and mitigating a potential resurgence later in the year provides even more justification for accelerating efforts to dramatically reduce open agricultural burning in India.

14.
Accid Anal Prev ; 144: 105595, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32534288

RESUMO

There is extensive literature into the mechanisms of injury in traffic crashes involving vulnerable road users (VRUs), but little research into the social or psychological factors in causation in these crash types. Attitudes and emotional associations can affect how people attend to objects in their visual environment and physical approach/avoidance responses, but few studies have extended these approaches into the road safety domain. Existing driving simulator studies of driver-bicyclist interactions have focused on driver behavior but not underlying attitudes and their effect on safety-related behaviors. This research explored the impact of implicit and explicit attitudes on drivers' behavior in interactions with bicyclists. In a driving simulator, various objective measures of safety (e.g., speed, passing distance, crash occurrence) were collected in an overtaking scenario. Participants' self-reported attitudes about driving and bicyclists were collected via survey instrument, along with an online test of subconscious attitudes called an Implicit Association Test, developed to examine preference between drivers and bicyclists. Importantly, this study examined not only distance, but duration and speed during overtaking. Results demonstrate that conscious attitudes affect how quickly and closely drivers overtake bicyclists. Participants who hold negative attitudes about bicyclists as a legitimate road user group passed significantly faster, while people with concerns about their knowledge or judgment about overtaking a bicyclist passed further and more slowly. Drivers self-identification as a bicyclist predicted higher passing speeds, while respondents who bicycle weekly drove closer but more slowly to the simulated bicyclist. These behaviors did not significantly differ based on the measure of implicit attitudes. The results of this study provide potential avenues for infrastructure and education interventions to improve pedestrian and bicyclist safety. Additionally, pairing driving simulator behavior with attitudinal measures represents a significant methodological contribution.


Assuntos
Condução de Veículo/psicologia , Ciclismo/psicologia , Acidentes de Trânsito/prevenção & controle , Adulto , Simulação por Computador , Feminino , Humanos , Masculino , Autorrelato
15.
Soil Tillage Res ; 199: 104595, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32362695

RESUMO

Climate smart agriculture (CSA) practices are emerging as sustainable alternative to conventional rice-wheat system to pull up natural resources degradation across south Asia. After five years of continuous CSA based experiment, a two years study was conducted to evaluate changes in microbial biomasses (microbial biomass carbon and nitrogen), enzyme activities (alkaline phosphatase, dehydrogenase and ß-glucosidase), nutrient release and uptake (N, P and K) at different wheat crop growth stages. Effect of CSA practices was also studied for carbon mineralization in an incubation experiment. Four scenarios (Sc) were included in this study- conventional tillage (CT) based rice-wheat system (Sc1), partial CSA based rice-wheat-mungbean system (Sc2), full CSA based rice-wheat-mungbean system (Sc3), and full CSA based maize-wheat-mungbean system (Sc4). Soil samples were collected from scenarios at 0-15 and 15-30 cm depth at different growth stages of wheat crop namely sowing, crown root initiation (CRI), active tillering, panicle initiation, and harvesting. Analysis of soil was done for chemical properties viz. pH, electrical conductivity, available N, P, K, NPK uptake and mineralizable carbon and biological properties viz., microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), dehydrogenase activity (DHA), alkaline phosphatase activity (APA) and ß-glucosidase. Significantly higher microbial biomass carbon (42 %) and nitrogen (79 %) were found in surface soil (0-15 cm depth) under CSA based scenarios (Sc2, Sc3 and Sc4) at harvest stage of wheat over CT based/ conventional scenario (Sc1). At surface soil, alkaline phosphatase, dehydrogenase and ß-glucosidase activity was 58, 14 and 13 % higher in CSA based scenarios, respectively than CT based scenario. CSA based scenarios showed significantly higher C mineralization after 3 days of the incubation experiment at harvest. An increase of respectively 15, 48 and 17 % of N, P and K uptake was observed with CSA based scenarios than CT based scenario. At harvest stage, 7 % higher amount of dry matter was reported with full CSA based scenarios (mean of Sc2 to Sc4) compared to Sc1. Higher wheat grain yield of ∼10 % was recorded with CSA based scenarios over CT based scenario. Therefore, CSA based scenarios with improved biological properties and nutrient availability and uptake at different wheat growth stages resulted in higher yields and hence need to be popularized among the farmers.

16.
Rev Sci Instrum ; 91(3): 033903, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32260020

RESUMO

In this study, we describe an advanced multi-functional, variable-energy positron beam system capable of measuring the energies of multiple "positron-induced" electrons in coincidence with the Doppler-shifted gamma photon resulting from the annihilation of the correlated positron. The measurements were carried out using the unique characteristics of the digital time-of-flight spectrometer and the gamma spectrometer available with the advanced positron beam system. These measurements have resulted in (i) the first digital time-of-flight spectrum of positron annihilation-induced Auger electrons generated using coincident signals from a high-purity Ge detector and a micro-channel plate, (ii) a two-dimensional array of the energy of Doppler-broadened annihilation gamma and the time-of-flight of positron-annihilation induced Auger electrons/secondary electrons measured in coincidence with the annihilation gamma photon, and (iii) the time-of-flight spectra of multiple secondary electrons ejected from a bilayer graphene surface as a result of the impact and/or annihilation of positrons. The novelty of the gamma-electron coincidence spectroscopy has been demonstrated by extracting the Doppler-broadened spectrum of gamma photons emitted due to the annihilation of positrons exclusively with 1s electrons of carbon. The width of the extracted Doppler-broadened gamma spectrum has been found to be consistent with the expected broadening of the annihilation gamma spectrum due to the momentum of the 1s electrons in carbon.

17.
BJOG ; 127(8): 1002-1013, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32141709

RESUMO

OBJECTIVE: To compare standard (native tissue) repair with synthetic mesh inlays or mesh kits. DESIGN: Randomised controlled trial. SETTING: Thirty-three UK hospitals. POPULATION: Women having surgery for recurrent prolapse. METHODS: Women recruited using remote randomisation. MAIN OUTCOME MEASURES: Prolapse symptoms, condition-specific quality-of-life and serious adverse effects. RESULTS: A Mean Pelvic Organ Prolapse Symptom Score at 1 year was similar for each comparison (standard 6.6 versus mesh inlay 6.1, mean difference [MD] -0.41, 95% CI -2.92 to 2.11: standard 6.6 versus mesh kit 5.9, MD -1.21 , 95% CI -4.13 to 1.72) but the confidence intervals did not exclude a minimally important clinical difference. There was no evidence of difference in any other outcome measure at 1 or 2 years. Serious adverse events, excluding mesh exposure, were similar at 1 year (standard 7/55 [13%] versus mesh inlay 5/52 [10%], risk ratio [RR] 1.05 [0.66-1.68]: standard 3/25 [12%] versus mesh kit 3/46 [7%], RR 0.49 [0.11-2.16]). Cumulative mesh exposure rates over 2 years were 7/52 (13%) in the mesh inlay arm, of whom four women required surgical revision; and 4/46 in the mesh kit arm (9%), of whom two required surgical revision. CONCLUSIONS: We did not find evidence of a difference in terms of prolapse symptoms from the use of mesh inlays or mesh kits in women undergoing repeat prolapse surgery. Although the sample size was too small to be conclusive, the results provide a substantive contribution to future meta-analysis. TWEETABLE ABSTRACT: There is not enough evidence to support use of synthetic mesh inlay or mesh kits for repeat prolapse surgery.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/métodos , Satisfação do Paciente/estatística & dados numéricos , Prolapso de Órgão Pélvico/cirurgia , Telas Cirúrgicas , Incontinência Urinária/cirurgia , Prolapso Uterino/cirurgia , Adulto , Coito , Feminino , Seguimentos , Procedimentos Cirúrgicos em Ginecologia/instrumentação , Humanos , Pessoa de Meia-Idade , Prolapso de Órgão Pélvico/fisiopatologia , Prolapso de Órgão Pélvico/psicologia , Qualidade de Vida , Reoperação/estatística & dados numéricos , Resultado do Tratamento , Incontinência Urinária/fisiopatologia , Incontinência Urinária/psicologia , Prolapso Uterino/fisiopatologia , Prolapso Uterino/psicologia
18.
Sci Rep ; 9(1): 15097, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641206

RESUMO

The nature of the neutrino is one of the major open questions in experimental nuclear and particle physics. The most sensitive known method to establish the Majorana nature of the neutrino is detection of the ultra-rare process of neutrinoless double beta decay. However, identification of one or a handful of decay events within a large mass of candidate isotope, without obfuscation by backgrounds is a formidable experimental challenge. One hypothetical method for achieving ultra- low-background neutrinoless double beta decay sensitivity is the detection of single 136Ba ions produced in the decay of 136Xe ("barium tagging"). To implement such a method, a single-ion-sensitive barium detector must be developed and demonstrated in bulk liquid or dry gaseous xenon. This paper reports on the development of two families of dry-phase barium chemosensor molecules for use in high pressure xenon gas detectors, synthesized specifically for this purpose. One particularly promising candidate, an anthracene substituted aza-18-crown-6 ether, is shown to respond in the dry phase with almost no intrinsic background from the unchelated state, and to be amenable to barium sensing through fluorescence microscopy. This interdisciplinary advance, paired with earlier work demonstrating sensitivity to single barium ions in solution, opens a new path toward single ion detection in high pressure xenon gas.

19.
Field Crops Res ; 239: 92-103, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31293292

RESUMO

Rice productivity in Eastern Indo-Gangetic plains (EIGP) is extremely low, in part due to the prevailing practice of cultivating long-duration transplanted rice under rainfed conditions which leads to water stress and significant yield losses in many seasons. Rice establishment alternatives such as direct seeded rice (DSR) require less water at planting but also are accompanied by climate risks that constrain adoption. For both conventional transplanted and DSR systems, successfully addressing climate-based production risks may provide a strong basis for sustainable rice intensification in EIGP. In this ex ante study of rice yield and yield variability, the APSIM cropping system model was used to evaluate the efficacy of risk-reducing management practices in both transplanted and DSR systems. Simulations were conducted with 44 years (1970-2013) of historical weather data from central Bihar, India. Results confirm that the prevailing farmer practice of transplanting long-duration cultivars under rainfed conditions (fTR) often results in delayed transplanting and the use of older seedlings, leading to low (median 1.6 t ha-1) and variable (Standard deviation (SD) 2.1 t ha-1) rice yields. To improve the fTR system, simulations suggest that adoption of medium-duration hybrid rice (3.2 t ha-1), provision of supplemental post-establishment irrigation (3.2 t ha-1), or transplanting appropriately aged seedlings (3.4 t ha -1) can double yields as single interventions while, in the case of supplemental irrigation, significantly reducing inter-annual production variability. Additional gains are achievable when interventions are layered: supplemental irrigation paired with medium-duration hybrids increased median rice yields to 4.6 t ha-1 with much lower variability (SD 1.0 t ha-1). In these improved systems where irrigation is used to transplant the crop, simulations revealed the importance of timely planting: high and stable yields are achievable for long-duration cultivars when transplanting is completed by 2 August with this window of opportunity extending to 16 August for medium-duration hybrids. In rainfed DSR systems, the potential pay-offs from single interventions were even higher with medium-duration hybrids resulting in a median yield of 4.5 t ha-1 against 1.8 t ha-1 with long-duration cultivars. For irrigated DSR systems, an optimum sowing window of early to mid-June was identified which resulted in higher and more stable yields with lower water requirements. Simulation results suggest several risk-reducing intensification pathways that can be selectively matched to farmer risk preferences and investment capabilities within the target region in EIGP.

20.
Trials ; 20(1): 318, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159849

RESUMO

BACKGROUND: Melanoma is common; 15,906 people in the UK were diagnosed with melanoma in 2015 and incidence has increased fivefold in 30 years. Melanoma affects old and young people, with poor prognosis once metastatic. UK guidelines recommend people treated for cutaneous melanoma receive extended outpatient, hospital follow up to detect recurrence or new primaries. Such follow up of the growing population of melanoma survivors is burdensome for both individuals and health services. Follow up is important since approximately 20% of patients with early-stage melanoma experience a recurrence and 4-8% develop a new primary; the risk of either is highest in the first 5 years. Achieving Self-directed Integrated Cancer Aftercare (ASICA) is a digital intervention to increase total-skin-self-examination (TSSE) by people treated for melanoma, with usual follow up. METHODS: We aim to recruit 240 adults with a previous first-stage 0-2C primary cutaneous melanoma, from secondary care in North-East Scotland and the East of England. Participants will be randomised to receive the ASICA intervention (a tablet-based digital intervention to prompt and support TSSE) or control group (treatment as usual). Patient-reported and clinical data will be collected at baseline, including the modified Melanoma Worry Scale (MWS), the Hospital Anxiety and Depression Scale (HADs), the EuroQoL 5-dimension 5-level questionnaire (EQ-5D-5 L), and questions about TSSE practice, intentions, self-efficacy and planning. Participants will be followed up by postal questionnaire at 3, 6 and 12 months following randomization, along with a 12-month review of clinical data. The primary timepoint for outcome analyses will be12 months after randomisation. DISCUSSION: If the ASICA intervention improves the practice of TSSE in those affected by melanoma, this may lead to improved psychological well-being and earlier detection of recurrent and new primary melanoma. This could impact both patients and National Health Service (NHS) resources. This study will determine if a full-scale randomised controlled trial can be undertaken in the UK NHS to provide the high-quality evidence needed to determine the effectiveness of the intervention. ASICA is a pilot study evaluating the effectiveness of the practice of digitally supported TSSE in those affected by melanoma. TRIAL REGISTRATION: Clinical Trials.gov, NCT03328247 . Registered on 1 November 2017.


Assuntos
Detecção Precoce de Câncer/métodos , Melanoma/diagnóstico , Recidiva Local de Neoplasia/diagnóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto , Assistência ao Convalescente , Interpretação Estatística de Dados , Humanos , Melanoma/psicologia , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Tamanho da Amostra , Autoexame , Inquéritos e Questionários
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