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1.
Blood ; 139(21): 3181-3193, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35040907

RESUMO

Anemia of inflammation, also known as anemia of chronic disease, is refractory to erythropoietin (EPO) treatment, but the mechanisms underlying the EPO refractory state are unclear. Here, we demonstrate that high mobility group box-1 protein (HMGB1), a damage-associated molecular pattern molecule recently implicated in anemia development during sepsis, leads to reduced expansion and increased death of EPO-sensitive erythroid precursors in human models of erythropoiesis. HMGB1 significantly attenuates EPO-mediated phosphorylation of the Janus kinase 2/STAT5 and mTOR signaling pathways. Genetic ablation of receptor for advanced glycation end products, the only known HMGB1 receptor expressed by erythroid precursors, does not rescue the deleterious effects of HMGB1 on EPO signaling, either in human or murine precursors. Furthermore, surface plasmon resonance studies highlight the ability of HMGB1 to interfere with the binding between EPO and the EPOR. Administration of a monoclonal anti-HMGB1 antibody after sepsis onset in mice partially restores EPO signaling in vivo. Thus, HMGB1-mediated restriction of EPO signaling contributes to the chronic phase of anemia of inflammation.


Assuntos
Anemia , Eritropoetina , Proteína HMGB1 , Sepse , Anemia/genética , Animais , Eritropoese/genética , Eritropoetina/metabolismo , Inflamação , Camundongos , Receptores da Eritropoetina/metabolismo , Sepse/complicações
2.
Stat Med ; 43(5): 953-982, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38146825

RESUMO

In recent decades, multilevel regression and poststratification (MRP) has surged in popularity for population inference. However, the validity of the estimates can depend on details of the model, and there is currently little research on validation. We explore how leave-one-out cross validation (LOO) can be used to compare Bayesian models for MRP. We investigate two approximate calculations of LOO: Pareto smoothed importance sampling (PSIS-LOO) and a survey-weighted alternative (WTD-PSIS-LOO). Using two simulation designs, we examine how accurately these two criteria recover the correct ordering of model goodness at predicting population and small-area estimands. Focusing first on variable selection, we find that neither PSIS-LOO nor WTD-PSIS-LOO correctly recovers the models' order for an MRP population estimand, although both criteria correctly identify the best and worst model. When considering small-area estimation, the best model differs for different small areas, highlighting the complexity of MRP validation. When considering different priors, the models' order seems slightly better at smaller-area levels. These findings suggest that, while not terrible, PSIS-LOO-based ranking techniques may not be suitable to evaluate MRP as a method. We suggest this is due to the aggregation stage of MRP, where individual-level prediction errors average out. We validate these results by applying to the real world National Health and Nutrition Examination Survey (NHANES) data in the United States. Altogether, these results show that PSIS-LOO-based model validation tools need to be used with caution and might not convey the full story when validating MRP as a method.


Assuntos
Projetos de Pesquisa , Humanos , Estados Unidos , Inquéritos Nutricionais , Teorema de Bayes , Fluxo de Trabalho , Simulação por Computador
3.
Can J Diet Pract Res ; 85(2): 59-65, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465628

RESUMO

Purpose: This study aimed to assess the reliability and validity of an online approach to monitoring food affordability in Ontario using the updated Ontario Nutritious Food Basket (ONFB).Methods: The ONFB was priced online in 12 large multi-chain grocery stores to test intra-/inter-rater reliability using percent agreement and intra-class correlations (ICCs). Then, the ONFB was priced in-store and online in 28 stores to estimate food price differences using paired t-tests and Pearson's correlation for all (n =1708) and matched items (same product/brand and purchase unit) (n = 1134).Results: Intra-/inter-rater agreement was high (95.4%/81.6%; ICC = 0.972, F = 69.9, p < 0.001). On average, in-store prices were less than $0.02 lower than online prices. There were no significant differences between mean in-store and online prices for all items (t = 0.504 p = 0.614). The mean price was almost perfectly correlated between in-store and online (fully matched: R = 0.993 p < 0.001; all items: R = 0.967 p < 0.001). Online monthly ONFB estimates for a family of four were strongly correlated (R = 0.937 p < 0.001) with estimates calculated using in-store data.Conclusions: Online pricing is a reliable and valid approach to food costing in Ontario that contributes to modernizing the monitoring of food affordability in Canada and abroad.


Assuntos
Comércio , Internet , Ontário , Reprodutibilidade dos Testes , Humanos , Abastecimento de Alimentos/economia , Abastecimento de Alimentos/estatística & dados numéricos , Custos e Análise de Custo , Alimentos/economia , Valor Nutritivo
4.
Med Humanit ; 50(1): 116-124, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38195242

RESUMO

Workplace suicide can have significant knock-on effects within an organisation, yet research has shown within the healthcare profession, not all staff receive suicide prevention training, and few employers take the time to reflect on the need to change workplace policies or practices following the death of a staff member to suicide. How staff suicide is communicated across an organisation and to family members is important. Effective crisis communication is critical for effective management for a timely and sensitive response to a staff suicide within an organisation. By doing so, workplaces can help to reduce the significant emotional trauma suicide can have on an employee, and support good mental health across its workforce. This study aimed to explore and understand the communication processes around staff suicide across a National Health Service (NHS) Trust and to provide recommendations based on these findings. Semi-structured interviews were conducted with 29 participants, each lasting approximately 90 min. The Consolidated Criteria for Reporting Qualitative Research (COREQ) guidelines were followed. Thematic analysis was used to analyse the data, resulting in seven themes being identified based on communication. Findings indicated that the Trust had no clear communication strategy in place for tackling staff suicide. Each suicide was handled differently, training across staff roles was lacking and operational procedures were deemed insensitive. This paper aimed to provide insight into the communication strategies used in the aftermath of a staff suicide. These findings highlight the inconsistency of the communication, lack of clear policy and guidance and the negative impact this had on staff. Further research is needed across NHS Trusts nationwide to gain insight into the current communication strategies in place to develop a national approach to clear communication following the death of an NHS worker to suicide. Tweetable abstract: Effective communication is critical in the aftermath of an NHS staff suicide. By doing so, NHS Trusts can help to reduce the trauma suicide can have on an employee and support good mental health across its workforce @stann2.


Assuntos
Medicina Estatal , Suicídio , Humanos , Família , Pesquisa Qualitativa , Comunicação
5.
Environ Sci Technol ; 57(9): 3671-3679, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36812385

RESUMO

Human norovirus (HuNoV) is an important cause of acute gastroenteritis and can be transmitted by water exposures, but its persistence in water is not well understood. Loss of HuNoV infectivity in surface water was compared with persistence of intact HuNoV capsids and genome segments. Surface water from a freshwater creek was filter-sterilized, inoculated with HuNoV (GII.4) purified from stool, and incubated at 15 or 20 °C. We measured HuNoV infectivity via the human intestinal enteroid system and HuNoV persistence via reverse transcription-quantitative polymerase chain reaction assays without (genome segment persistence) or with (intact viral capsid persistence) enzymatic pretreatment to digest naked RNA. For infectious HuNoV, results ranged from no significant decay to a decay rate constant ("k") of 2.2 day-1. In one creek water sample, genome damage was likely a dominant inactivation mechanism. In other samples from the same creek, loss of HuNoV infectivity could not be attributed to genome damage or capsid cleavage. The range in k and the difference in the inactivation mechanism observed in water from the same site could not be explained, but variable constituents in the environmental matrix could have contributed. Thus, a single k may be insufficient for modeling virus inactivation in surface waters.


Assuntos
Norovirus , Água , Humanos , Norovirus/genética , Inativação de Vírus , Água Doce
6.
Heart Lung Circ ; 32(10): 1222-1229, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37758636

RESUMO

AIM: We investigated the prevalence of incidental coronary artery calcifications (CAC) from non-electrocardiogram (ECG)-gated computed tomography (CT) chest (both contrast and non-contrast) for inpatients. We also assessed for downstream investigation and statin prescription from the inpatient teams. Incidental CAC are frequent findings on non-ECG-gated CT chest. It is associated with adverse prognosis in multiple patient cohorts. METHOD: All non-ECG-gated CT chest done as inpatients from a single centre referred from 1 January 2022 to 31 December 2022 with reported incidental CAC were reviewed for inclusion. Patients who had a history of known coronary artery disease, history of coronary stent or bypass, and presence of cardiac devices were excluded. RESULTS: Total of 123 patients were included, making the prevalence 6.2% (123/1,980). The median age is 76 years (interquartile range 69-85) and predominantly male at 54.5%. The majority of CT chest done were contrasted scans (91.1%). Only 26.8% of CAC were reported on severity with visual quantification, with 7.3% each reported for both moderate and severe CAC. Only 2.4% of CAC were reported in the conclusion of the CT report. Most of these patients were asymptomatic (34.1%). A total of 20.3% of patients had further tests done. Inpatient hospital mortality was 8.1%. About 23.6% and 34.1% of patients were on aspirin and statin therapy respectively at baseline. There was only 1 patient (1.2%) who was prescribed with new statin therapy on discharge. CONCLUSION: Incidental CAC is prevalent in inpatient settings and remains under-recognised by ordering clinicians, with low prescription rate of statin therapy. Practice-changing measures to standardise reporting of incidental CAC is needed to identify patients with subclinical coronary disease and initiate preventive interventions.


Assuntos
Doença da Artéria Coronariana , Inibidores de Hidroximetilglutaril-CoA Redutases , Calcificação Vascular , Humanos , Masculino , Idoso , Feminino , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/complicações , Angiografia Coronária/métodos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Estudos Retrospectivos , Radiografia Torácica/métodos , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia
7.
Emerg Infect Dis ; 28(5): 940-947, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35349402

RESUMO

Monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) is critical for public health management of coronavirus disease. Sequencing is resource-intensive and incompletely representative, and not all isolates can be sequenced. Because wastewater SARS-CoV-2 RNA concentrations correlate with coronavirus disease incidence in sewersheds, tracking VOCs through wastewater is appealing. We developed digital reverse transcription PCRs to monitor abundance of select mutations in Alpha and Delta VOCs in wastewater settled solids, applied these to July 2020-August 2021 samples from 2 large US metropolitan sewersheds, and compared results to estimates of VOC abundance from case isolate sequencing. Wastewater measurements tracked closely with case isolate estimates (Alpha, rp 0.82-0.88; Delta, rp 0.97). Mutations were detected in wastewater even at levels <5% of total SARS-CoV-2 RNA and in samples available 1-3 weeks before case isolate results. Wastewater variant monitoring should be strategically deployed to complement case isolate sequencing.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Humanos , RNA Viral/genética , SARS-CoV-2/genética , Estados Unidos/epidemiologia , Águas Residuárias , Vigilância Epidemiológica Baseada em Águas Residuárias
8.
Fam Community Health ; 45(4): 228-237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35985023

RESUMO

Land grant universities are a key provider of community-based health promotion programs through the Cooperative Extension Service. However, Extension's current approach to addressing systemic social determinants of health is incomplete and inconsistent. The purpose of this study was to explore Extension health educators' perceptions of demand for health promotion programming targeting audiences most likely to experience health inequities. Health educators within 2 state Extension systems were invited to complete an online survey based on a capacity building model. Survey questions included rating perceptions of demand for programming for health disparate populations: low-income; Black and African American; Hispanic, Latino/a, Latinx; persons with disabilities; immigrants and refugees; and lesbian, gay, bisexual, and transgender. Analysis of variance and Bonferroni post hoc testing was used to determine differences in perceived demand between populations. Ninety-six educators completed the survey. Perceived demand for low-income population programming was significantly higher than for other populations. Perceived programming demand for immigrants and refugees and lesbian, gay, bisexual, and transgender people was significantly lower than for other populations. Individual and organizational-level factors, including racism and Extension's historical scope, likely contribute to the results. Engaging historically excluded Extension audiences requires time and resources to improve the Extension system and educator capacity for relationship building, trust building, and communication.


Assuntos
Refugiados , Minorias Sexuais e de Gênero , Fortalecimento Institucional , Feminino , Desigualdades de Saúde , Promoção da Saúde/métodos , Humanos
9.
Surgeon ; 20(5): e187-e194, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34334310

RESUMO

Surgical training traditionally has been afforded an apprenticeship model of learning but has since strived to become a structured programme of learning events and progress. Peer led training in an undergraduate course is increasingly utilised but its role in postgraduate/speciality training is not widely published. This paper reviews the historical roots of surgical training and current educational theories which underpin the proposal of a new tool, the SSuRF approach, an innovate aide memoire to assist peer led technical/operative surgical training with the hope that this approach will allow peers, especially those who do not have much formal educational training, to teach those junior using a structured format and document this within their workplace based assessment. This contrasts with the rather tick box exercise that it is currently, and hence may promote a deeper learning throughout the teaching experience.


Assuntos
Educação de Graduação em Medicina , Grupo Associado , Competência Clínica , Currículo , Humanos , Aprendizagem , Ensino
10.
Wilderness Environ Med ; 33(1): 59-65, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35067448

RESUMO

INTRODUCTION: Participants at Philmont Scout Ranch embark on 12-d treks with pre-trek physical conditioning and medical clearance by their primary care physician. In this study, we investigated potential contributing factors to self-reported musculoskeletal injuries during a backpack trek. METHODS: This study was a prospective cohort study that used a 3-part survey administered to participants before, during, and after their trek from June through August 2019. Health history and demographic information were retrieved from each hiker's medical record. A logistic regression model was used to assess factors associated with injuries, and odds ratios and 95% confidence intervals were reported. RESULTS: There were 1206 individuals enrolled in this study, and none withdrew from participation. The median age of the participants was 17 y (interquartile range 15-47); 1130 were male, 75 were female, and 1 was of unknown sex. Injuries were reported by 7% (n=88) of participants while in the backcountry, with injuries occurring in various anatomic locations (knee, ankle, leg, foot, hand, arm). Participants without missing data (74%; n=897) were included in the logistical regression analysis to describe factors significantly associated with injury. Factors significantly associated with injury included greater backpack weight to body weight ratio, body mass index greater than 30 kg·m-2, and past injuries that required a doctor visit. CONCLUSIONS: Self-reported injuries while hiking at Philmont Scout Ranch are infrequent and do not often require evacuation or advanced medical care. Camp policies to maintain appropriate backpack weight and counseling of obese and previously injured individuals may mitigate injury occurrence.


Assuntos
Esportes , Índice de Massa Corporal , Feminino , , Humanos , Extremidade Inferior , Masculino , Estudos Prospectivos
11.
Blood Cells Mol Dis ; 87: 102524, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33341069

RESUMO

Inherited bone marrow failure syndromes (IBMFS) are heterogeneous disorders characterized by dysregulated hematopoiesis in various lineages, developmental anomalies, and predisposition to malignancy. The scat (severe combined anemia and thrombocytopenia) mouse model is a model of IBMFS with a phenotype of pancytopenia cycling through crises and remission. Scat carries an autosomal recessive missense mutation in Rasa3 that results in RASA3 mislocalization and loss of function. RASA3 functions as a Ras-GTPase activating protein (GAP), and its loss of function in scat results in increased erythroid RAS activity and reactive oxygen species (ROS) and altered erythroid cell cycle progression, culminating in delayed terminal erythroid differentiation. Here we sought to further resolve the erythroid cell cycle defect in scat through ex vivo flow cytometric analyses. These studies revealed a specific G0/G1 accumulation in scat bone marrow (BM) polychromatophilic erythroblasts and scat BM Ter119-/c-KIT+/CD71lo/med progenitors, with no changes evident in equivalent scat spleen populations. Systematic analyses of RNAseq data from megakaryocyte-erythroid progenitors (MEPs) in scat crisis vs. scat partial remission reveal altered expression of genes involved in the G1-S checkpoint. Together, these data indicate a precise, biphasic role for RASA3 in regulating the cell cycle during erythropoiesis with relevance to hematopoietic disease progression.


Assuntos
Células Eritroides/citologia , Eritropoese , Proteínas Ativadoras de GTPase/metabolismo , Animais , Ciclo Celular , Células Cultivadas , Células Eritroides/metabolismo , Proteínas Ativadoras de GTPase/genética , Camundongos Endogâmicos BALB C , Mutação de Sentido Incorreto , Proteínas ras/metabolismo
12.
Environ Sci Technol ; 55(6): 3514-3519, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33656856

RESUMO

Wastewater-based epidemiology is an emerging tool for tracking the spread of SARS-CoV-2 through populations. However, many factors influence recovery and quantification of SARS-CoV-2 from wastewater, complicating data interpretation. Specifically, these factors may differentially affect the measured virus concentration, depending on the laboratory methods used to perform the test. Many laboratories add a proxy virus to wastewater samples to determine losses associated with concentration and extraction of viral RNA. While measuring recovery of a proxy virus is an important process control, in this piece, we describe the caveats and limitations to the interpretation of this control, including that it typically does not account for losses during RNA extraction. We recommend reporting the directly measured concentration data alongside the measured recovery efficiency, rather than attempting to correct the concentration for recovery efficiency. Even though the ability to directly compare SARS-CoV-2 concentrations from different sampling locations determined using different methods is limited, concentration data (uncorrected for recovery) can be useful for public health response.


Assuntos
COVID-19 , Vírus , Humanos , RNA Viral , SARS-CoV-2 , Águas Residuárias
13.
Environ Sci Technol ; 55(8): 4880-4888, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33759506

RESUMO

Wastewater-based epidemiology is an emerging tool to monitor COVID-19 infection levels by measuring the concentration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in wastewater. There remains a need to improve wastewater RNA extraction methods' sensitivity, speed, and reduce reliance on often expensive commercial reagents to make wastewater-based epidemiology more accessible. We present a kit-free wastewater RNA extraction method, titled "Sewage, Salt, Silica and SARS-CoV-2" (4S), that employs the abundant and affordable reagents sodium chloride (NaCl), ethanol, and silica RNA capture matrices to recover sixfold more SARS-CoV-2 RNA from wastewater than an existing ultrafiltration-based method. The 4S method concurrently recovered pepper mild mottle virus (PMMoV) and human 18S ribosomal subunit rRNA, which have been proposed as fecal concentration controls. The SARS-CoV-2 RNA concentrations measured in three sewersheds corresponded to the relative prevalence of COVID-19 infection determined via clinical testing. Lastly, controlled experiments indicate that the 4S method prevented RNA degradation during storage of wastewater samples, was compatible with heat pasteurization, and in our experience, 20 samples can be processed by one lab technician in approximately 2 h. Overall, the 4S method is promising for effective, economical, and accessible wastewater-based epidemiology for SARS-CoV-2, providing another tool to fight the global pandemic.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , RNA Viral/genética , Esgotos , Dióxido de Silício , Cloreto de Sódio , Águas Residuárias
14.
BMC Public Health ; 21(1): 1100, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107896

RESUMO

BACKGROUND: In 2015, the Partnership for a Healthier America launched the branded Fruits & Veggies (FNV) Campaign to apply a unique industry-inspired marketing approach to promote fruit and vegetable sales and intake to moms and teens in two US pilot markets: Fresno, California and Hampton Roads, Virginia. The aims of this cross-sectional study were to: 1) assess brand awareness and fruit- and vegetable-related outcomes among FNV Campaign target audiences in the California and Virginia market locations; and 2) examine whether reported awareness of the FNV Campaign was associated with differences in fruit- and vegetable-related cognitive and behavioral outcomes. METHODS: Data for this cross-sectional study were collected using an online survey administered to a non-probability convenience sample (n = 1604; February-July 2017) of youth aged 14-20 years (n = 744) and moms aged 21-36 years (n = 860) in the two pilot markets. Descriptive statistics were computed and outcomes compared between unaware and aware respondents, controlling for sociodemographic covariates. Multivariate analysis of covariance (MANCOVA) was conducted to assess whether fruit- and vegetable-related attitude, belief, and encouragement outcomes differed by FNV Campaign awareness; logistic regression was used to examine associations between FNV brand awareness and dichotomous variables (fruit- and vegetable-related behavioral intentions, trying new fruits and vegetables); and ANCOVA was used to assess associations with daily fruit and vegetable intake frequency. RESULTS: Approximately 20% (n = 315/1604) of respondents reported awareness of the FNV Campaign. Youth that reported awareness of the FNV Campaign (n = 167, 22.4%) had higher intentions to buy (p = 0.003) and eat (p = 0.009) fruits and vegetables than unaware respondents. Mothers that reported awareness of the FNV Campaign (n = 148, 17.2%) reported greater encouragement for friends and family to eat fruits and vegetables (p = 0.013) and were approximately 1.5 times more likely to report trying a new fruit or vegetable (p = 0.04) than mothers unaware of the Campaign. Daily fruit and vegetable intake frequency did not differ by Campaign awareness. CONCLUSIONS: FNV Campaign awareness was associated with limited but positive short- and intermediate-term cognitive and behavioral outcomes among target audience respondents. These findings can inform future research to enhance understanding and improve the FNV Campaign as it is expanded to new markets nationwide.


Assuntos
Frutas , Verduras , Adolescente , California , Estudos Transversais , Dieta , Comportamento Alimentar , Feminino , Humanos , Virginia
15.
Prev Sci ; 22(7): 903-912, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33733430

RESUMO

Extension professionals have high autonomy to adapt the programs they deliver. However, fidelity is typically not reported, so it is unknown what adaptations are made. It is also unknown whether agents have the necessary training to adapt programs while maintaining fidelity to the core components. The purpose of this study was to determine (1) adaptations that Extension agents and specialists are making to programs they deliver, (2) the reasons for making these adaptations, (3) timing of adaptations, and (4) Extension agents' and specialists' understanding of the adaptation process. Extension agents and specialists nationwide were invited to complete a survey which queried about adaptations based on the traffic light model, adaptome, and adaptation taxonomy. Specifically, the traffic light model assigns a color for adaptations: tailoring language or pictures (green), adding/substituting activities or session sequence (yellow), or deleting lessons and decreasing timeline or session length (red). Responses were received from 98 agents and 24 specialists. Most agents and specialists reported making green (85% and 79%, respectively), yellow (89% and 75%), and red light changes (81% and 58%). Agents were significantly more likely than specialists to change the age appropriateness of lessons or activities, respond to individual client needs, substitute activities, delete lessons or activities, decrease the length and/or number of sessions, and shorten the program timeline. Within green light changes, each of those that could increase cultural appropriateness (tailoring language, scenarios, and pictures) were reported by less than 50% of agents and specialists. Of the most common adaptations reported, the primary reasons for these decisions were difficulty retaining or engaging participants and lack of time/competing demands on time. Most adaptations were made before the program was delivered. Agents rated their confidence level in the program adaptation process as somewhat confident to confident. Dissemination and implementation strategies to improve program adaptation within Extension are needed, including participatory approaches, training on the adaptation process, bi-directional evidence-based program repositories, and organizational-level changes.


Assuntos
Promoção da Saúde , Humanos
16.
Behav Res Methods ; 49(6): 2219-2234, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28364284

RESUMO

As Bayesian methods become more popular among behavioral scientists, they will inevitably be applied in situations that violate the assumptions underpinning typical models used to guide statistical inference. With this in mind, it is important to know something about how robust Bayesian methods are to the violation of those assumptions. In this paper, we focus on the problem of contaminated data (such as data with outliers or conflicts present), with specific application to the problem of estimating a credible interval for the population mean. We evaluate five Bayesian methods for constructing a credible interval, using toy examples to illustrate the qualitative behavior of different approaches in the presence of contaminants, and an extensive simulation study to quantify the robustness of each method. We find that the "default" normal model used in most Bayesian data analyses is not robust, and that approaches based on the Bayesian bootstrap are only robust in limited circumstances. A simple parametric model based on Tukey's "contaminated normal model" and a model based on the t-distribution were markedly more robust. However, the contaminated normal model had the added benefit of estimating which data points were discounted as outliers and which were not.


Assuntos
Teorema de Bayes , Interpretação Estatística de Dados , Modelos Estatísticos , Humanos
17.
Environ Sci Process Impacts ; 26(1): 71-81, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38078556

RESUMO

Modeling the fate and transport of viruses and their genetic material in surface water is necessary to assess risks associated with contaminated surface waters and to inform environmental surveillance efforts. Temperature has been identified as a key variable affecting virus persistence in surface waters, but the effects of the presence of biological and inert particles and of their interaction with temperature have not been well characterized. We assessed these effects on the persistence of human norovirus (HuNoV) genotype II.4 purified from stool and MS2 in surface water. Raw or filter-sterilized creek water microcosms were inoculated and incubated in the dark at 10 °C, 15 °C, and 20 °C. HuNoV (i.e., genome segments and intact capsids) and MS2 (i.e., infectious MS2, genome segments, and intact capsids) concentrations were followed over 36 days. The range in positive, significant first-order decay rate constants for HuNoV in this study was 0.14 to 0.69 day-1 compared with 0.026 to 0.71 day-1 for that of MS2. Decay rate constants for HuNoV genome segments and infectious MS2 were largest in creek water that included biological and inert particles and incubated at higher temperatures. In addition, for HuNoV and MS2 incubated in raw or filter-sterilized creek water at 15 °C, capsid damage was not identified as a dominant inactivation mechanism. Environmental processes and events that affect surface water biological and inert particles, temperature, or both could lead to variable virus decay rate constants. Incorporating the effects of particles, temperature, and their interaction could enhance models of virus fate and transport in surface water.


Assuntos
Norovirus , Vírus , Humanos , Norovirus/genética , Temperatura , Água , Poluição da Água
18.
Health Educ Behav ; 50(3): 416-429, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991406

RESUMO

It is well known that perceptions of intervention characteristics (e.g., cost, source, evidence strength and quality) are a critical link from dissemination to implementation. What is less known is the process by which researchers understand the characteristics most valued by key intermediaries (i.e., real-world decision-makers), particularly in the federal system of Cooperative Extension. In Extension, university-based specialists are available to assist county-based agents in program selection, delivery, and evaluation. For this work, a sequential explanatory mixed-methods design was used to conduct surveys and semi-structured interviews, informed by the Diffusion of Innovations theory and Consolidated Framework for Implementation Research. Educators and specialists were recruited across 47 states to identify characteristics of health promotion interventions that facilitate the adoption decision-making process. Analysis of intervention attribute importance survey data was conducted through a one-way ANOVA with Bonferroni post hoc test to determine individual variable differences between responses. Interviews underwent a conventional content analysis. In total, 121 educators and 47 specialists from 33 states completed the survey. Eighteen educators and 10 specialists completed interviews. Educators and specialists valued components such as the community need for the intervention, and potential reach compared with other components including previous delivery settings and external funding of the intervention (p < .05). Qualitative data indicated divergence between educators and specialists; educators valued understanding the intervention cost (time and training) and specialists valued the evidence base and external funding available. Intervention developers should communicate information valued by different stakeholders to improve the adoption of evidence-based interventions.


Assuntos
Educadores em Saúde , Humanos , Promoção da Saúde
19.
J Cyst Fibros ; 22(3): 570-576, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36402730

RESUMO

BACKGROUND: Regular participation in physical activity (PA) is encouraged for people with Cystic Fibrosis (CF). This study aimed to assess the effectiveness of an intervention using wearable technology, goal setting and text message feedback on PA and health outcomes in people with CF. METHODS: This was a pilot randomised trial conducted at University Hospital Limerick. Participants were randomly assigned to the intervention (INT) or active comparator (AC). The 12-week intervention consisted of wearable technology (Fitbit Charge 2) which was remotely monitored, and participants set step count goals. Participants were sent a one-way text message once a week over 12 weeks to positively reinforce and encourage PA participation. The AC group received the wearable technology alone. Follow up was assessed at 24 weeks. Outcomes assessed were PA, aerobic capacity, lung function, sleep, quality of life and wellbeing. RESULTS: Step count increased significantly for the INT group over 12 weeks when compared to the AC group (p=0.019). The INT group had a 28% week-to-week percentage change (Weeks 1-12), while the AC group reduced by 1%, p=0.023. Within group changes demonstrated that VO2 peak (ml/kg/min) significantly increased for the INT group at 12 weeks (24.4 ±7.65 to 26.13 ±7.79, p=0.003) but not at 24 weeks (24.45 ±7.05, p=0.776). There were no significant differences observed for VO2 peak (ml/kg/min) for the AC group. There was no significant effect on lung function, sleep, well-being, or quality of life for either group. CONCLUSIONS: A personalised PA intervention using wearable technology, goal setting and text message feedback increased PA and aerobic capacity in people with CF. Integration of this intervention into usual care may encourage regular PA participation for people with CF.


Assuntos
Fibrose Cística , Envio de Mensagens de Texto , Dispositivos Eletrônicos Vestíveis , Humanos , Adulto , Fibrose Cística/terapia , Retroalimentação , Qualidade de Vida , Projetos Piloto , Objetivos , Exercício Físico
20.
JACC Adv ; 2(8): 100637, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38938360

RESUMO

Background: Traditional methods of risk assessment for thoracic aortic aneurysm (TAA) based on aneurysm size alone have been called into question as being unreliable in predicting complications. Biomechanical function of aortic tissue may be a better predictor of risk, but it is difficult to determine in vivo. Objectives: This study investigates using a machine learning (ML) model as a correlative measure of energy loss, a measure of TAA biomechanical function. Methods: Biaxial tensile testing was performed on resected TAA tissue collected from patients undergoing surgery. The energy loss of the tissue was calculated and used as the representative output. Input parameters were collected from clinical assessments including observations from medical scans and genetic paneling. Four ML algorithms including Gaussian process regression were trained in Matlab. Results: A total of 158 patients were considered (mean age 62 years, range 22-89 years, 78% male), including 11 healthy controls. The mean ascending aortic diameter was 47 ± 10 mm, with 46% having a bicuspid aortic valve. The best-performing model was found to give a greater correlative measure to energy loss (R2 = 0.63) than the surprisingly poor performance of aortic diameter (R2 = 0.26) and indexed aortic size (R2 = 0.32). An echocardiogram-derived stiffness metric was investigated on a smaller subcohort of 67 patients as an additional input, improving the correlative performance from R2 = 0.46 to R2 = 0.62. Conclusions: A preliminary set of models demonstrated the ability of a ML algorithm to improve prediction of the mechanical function of TAA tissue. This model can use clinical data to provide additional information for risk stratification.

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