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1.
Entropy (Basel) ; 24(12)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36554187

RESUMO

A wide range of machine-learning-based approaches have been developed in the past decade, increasing our ability to accurately model nonlinear and nonadditive response surfaces. This has improved performance for inferential tasks such as estimating average treatment effects in situations where standard parametric models may not fit the data well. These methods have also shown promise for the related task of identifying heterogeneous treatment effects. However, the estimation of both overall and heterogeneous treatment effects can be hampered when data are structured within groups if we fail to correctly model the dependence between observations. Most machine learning methods do not readily accommodate such structure. This paper introduces a new algorithm, stan4bart, that combines the flexibility of Bayesian Additive Regression Trees (BART) for fitting nonlinear response surfaces with the computational and statistical efficiencies of using Stan for the parametric components of the model. We demonstrate how stan4bart can be used to estimate average, subgroup, and individual-level treatment effects with stronger performance than other flexible approaches that ignore the multilevel structure of the data as well as multilevel approaches that have strict parametric forms.

2.
Am J Ther ; 23(4): e1074-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26164024

RESUMO

Pulmonary embolism (PE) is a common clinical problem affecting 600,000 patients per year in the United States. Although the diagnosis can be easily confirmed by imaging techniques, such as computed tomographic angiography of the chest, the identification of underlying mechanism leading to PE is important for appropriate duration of anticoagulation, and prevention of subsequent episodes. The differential diagnosis of underlying mechanism is broad and must include careful review of medication history. Drug-related thromboembolic disease can be easily missed and may have catastrophic consequences. The identification of the culprit drug is important for prevention of subsequent episodes and choosing appropriate duration of anticoagulation. We report a case of a middle-aged man who developed PE after administration of intravenous immunoglobulin.


Assuntos
Deficiência de IgG/tratamento farmacológico , Imunoglobulinas Intravenosas/efeitos adversos , Embolia Pulmonar/induzido quimicamente , Diagnóstico Diferencial , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/diagnóstico por imagem , Trombose Venosa/induzido quimicamente , Trombose Venosa/diagnóstico por imagem
3.
Environ Monit Assess ; 187(2): 25, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25626562

RESUMO

An assessment of the reliability of the Scanning Imaging Absorption Spectrometer for Atmospheric Cartography (SCIAMACHY) satellite sensor measurements to interpolate tropospheric concentrations of carbon monoxide considering the low-latitude climate of the Niger Delta region in Nigeria was conducted. Monthly SCIAMACHY carbon monoxide (CO) column measurements from January 2,003 to December 2005 were interpolated using ordinary kriging technique. The spatio-temporal variations observed in the reliability were based on proximity to the Atlantic Ocean, seasonal variations in the intensities of rainfall and relative humidity, the presence of dust particles from the Sahara desert, industrialization in Southwest Nigeria and biomass burning during the dry season in Northern Nigeria. Spatial reliabilities of 74 and 42 % are observed for the inland and coastal areas, respectively. Temporally, average reliability of 61 and 55 % occur during the dry and wet seasons, respectively. Reliability in the inland and coastal areas was 72 and 38 % during the wet season, and 75 and 46 % during the dry season, respectively. Based on the results, the WFM-DOAS SCIAMACHY CO data product used for this study is therefore relevant in the assessment of CO concentrations in developing countries within the low latitudes that could not afford monitoring infrastructure due to the required high costs. Although the SCIAMACHY sensor is no longer available, it provided cost-effective, reliable and accessible data that could support air quality assessment in developing countries.


Assuntos
Poluentes Atmosféricos/análise , Monóxido de Carbono/análise , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Imagens de Satélites , Altitude , Oceano Atlântico , Biomassa , Poeira/análise , Reprodutibilidade dos Testes , Estações do Ano
4.
Infect Immun ; 81(3): 723-32, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23264052

RESUMO

MicroRNAs (miRNAs) are small noncoding molecules that control gene expression posttranscriptionally, with microRNA-155 (miR-155) one of the first to be implicated in immune regulation. Here, we show that miR-155-deficient mice are less able to eradicate a mucosal Citrobacter rodentium infection than wild-type C57BL/6 mice. miR-155-deficient mice exhibited prolonged colonization associated with a higher C. rodentium burden in gastrointestinal tissue and spread into systemic tissues. Germinal center formation and humoral immune responses against C. rodentium were severely impaired in infected miR-155-deficient mice. A similarly susceptible phenotype was observed in µMT mice reconstituted with miR-155-deficient B cells, indicating that miR-155 is required intrinsically for mediating protection against this predominantly luminal bacterial pathogen.


Assuntos
Citrobacter rodentium , Infecções por Enterobacteriaceae/microbiologia , Predisposição Genética para Doença , MicroRNAs/metabolismo , Animais , Colite/genética , Colite/microbiologia , Colite/patologia , Infecções por Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/imunologia , Feminino , Regulação da Expressão Gênica/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
5.
Cancer Nurs ; 46(1): 3-13, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34974507

RESUMO

BACKGROUND: Patients with advanced cancer are increasingly experiencing financial hardship (FH) and associated negative health outcomes. OBJECTIVE: The aims of this study were to describe FH and explore its relationship to quality of life (QOL) in patients with advanced cancer receiving outpatient palliative care (PC). METHODS: Validated questionnaires assessed FH, QOL dimensions, symptom burden, and sociodemographic and clinical characteristics. Descriptive statistics characterized the sample and described FH. Pearson correlation and linear regression assessed relationships between FH and QOL. RESULTS: The average participant (n = 78) age was 56.6 (SD, 12.2) years. Most were female (56.4%), White (50%) or Black (46.2%), and had a range of education, partner statuses, and cancer diagnoses. Median time since cancer diagnosis was 35.5 months (interquartile range, 9-57.3 months). Highest mean symptom burden scores were for pain (2.5 [SD, 1.0]) and fatigue (2.0 [SD, 1.1]), on a 0- to 3-point scale (higher score representing worse symptom burden). The median COST (COmphrehensive Score for financial Toxicity) score was 15.0 (interquartile range, 9.0-23.0). Most (70%) had some (n = 43) or extreme (n = 9) difficulty paying for basic needs. Greater than 28% (n = 21) incurred cancer-related debt. Multivariate models indicated that FH negatively affected role limitations due to physical health ( P = .008), pain ( P = .003), and emotional well-being ( P = .017) QOL dimensions. CONCLUSIONS: Financial hardship, QOL, and symptom burden scores demonstrate need for continued support for and research among patients with advanced cancer. Data support links between FH and important QOL dimensions. Larger, longitudinal studies are needed to understand how FH affects QOL in patients with advanced cancer. IMPLICATIONS FOR PRACTICE: Proactive financial assessment and interventions are needed to support patients with advanced cancer experiencing the cumulative effects of cancer and its treatment.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Qualidade de Vida/psicologia , Cuidados Paliativos , Estresse Financeiro , Projetos Piloto , Pacientes Ambulatoriais , Neoplasias/psicologia , Inquéritos e Questionários , Dor
6.
CBE Life Sci Educ ; 21(2): ar22, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35324271

RESUMO

Science, technology, engineering, and mathematics (STEM) career barriers persist for individuals from marginalized communities due to financial and educational inequality, unconscious bias, and other disadvantaging factors. To evaluate differences in plans and interests between historically underrepresented (UR) and well-represented (WR) groups, we surveyed more than 3000 undergraduates enrolled in chemistry courses. Survey responses showed all groups arrived on campus with similar interests in learning more about science research. Over the 4 years of college, WR students maintained their interest levels, but UR students did not, creating a widening gap between the groups. Without intervention, UR students participated in lab research at lower rates than their WR peers. A case study pilot program, Biosciences Collaborative for Research Engagement (BioCoRE), encouraged STEM research exploration by undergraduates from marginalized communities. BioCoRE provided mentoring and programming that increased community cohesion and cultivated students' intrinsic scientific mindsets. Our data showed that there was no statistical significant difference between BioCoRE WR and UR students when surveyed about plans for a medical profession, graduate school, and laboratory scientific research. In addition, BioCoRE participants reported higher levels of confidence in conducting research than non-BioCoRE Scholars. We now have the highest annual number of UR students moving into PhD programs in our institution's history.


Assuntos
Grupos Minoritários , Estudantes , Engenharia/educação , Humanos , Grupos Minoritários/educação , Tecnologia/educação , Universidades
7.
Mol Microbiol ; 76(2): 318-30, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20525091

RESUMO

Specificity of protein-protein interactions plays a vital role in signal transduction. The chemosensory pathway of Rhodobacter sphaeroides comprises multiple homologues of chemotaxis proteins characterized in organisms such as Escherichia coli. Three CheA homologues are essential for chemotaxis in R. sphaeroides under laboratory conditions. These CheAs are differentially localized to two chemosensory clusters, one at the cell pole and one in the cytoplasm. The polar CheA, CheA(2), has the same domain structure as E. coli CheA and can phosphorylate all R. sphaeroides chemotaxis response regulators. CheA(3) and CheA(4) independently localize to the cytoplasmic cluster; each protein has a subset of the CheA domains, with CheA(3) phosphorylating CheA(4) together making a functional CheA protein. Interestingly, CheA(3)-P can only phosphorylate two response regulators, CheY(6) and CheB(2). R. sphaeroides CheAs exhibit two interesting differences in specificity: (i) the response regulators that they phosphorylate and (ii) the chemosensory cluster to which they localize. Using a domain-swapping approach we investigated the role of the P1 and P5 CheA domains in determining these specificities. We show that the P1 domain is sufficient to determine which response regulators will be phosphorylated in vitro while the P5 domain is sufficient to localize the CheAs to a specific chemosensory cluster.


Assuntos
Proteínas de Bactérias/metabolismo , Quimiotaxia , Proteínas Quinases/metabolismo , Rhodobacter sphaeroides/enzimologia , Rhodobacter sphaeroides/fisiologia , Sequência de Aminoácidos , Membrana Celular/química , Citoplasma/química , Embaralhamento de DNA , Histidina Quinase , Modelos Biológicos , Modelos Moleculares , Dados de Sequência Molecular , Fosforilação , Estrutura Terciária de Proteína , Rhodobacter sphaeroides/química , Alinhamento de Sequência , Especificidade por Substrato
8.
Environ Sci Pollut Res Int ; 24(8): 7788-7808, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28130720

RESUMO

Environmental monitoring in middle- and low-income countries is hampered by many factors which include enactment and enforcement of legislations; deficiencies in environmental data reporting and documentation; inconsistent, incomplete and unverifiable data; a lack of access to data; and technical expertise. This paper describes the processes undertaken and the major challenges encountered in the construction of the first Niger Delta Emission Inventory (NDEI) for criteria air pollutants and CO2 released from the anthropogenic activities in the region. This study focused on using publicly available government and research data. The NDEI has been designed to provide a Geographic Information System-based component of an air quality and carbon management framework. The NDEI infrastructure was designed and constructed at 1-, 10- and 20-km grid resolutions for point, line and area sources using industry standard processes and emission factors derived from activities similar to those in the Niger Delta. Due to inadequate, incomplete, potentially inaccurate and unavailable data, the infrastructure was populated with data based on a series of best possible assumptions for key emission sources. This produces outputs with variable levels of certainty, which also highlights the critical challenges in the estimation of emissions from a developing country. However, the infrastructure is functional and has the ability to produce spatially resolved emission estimates.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Dióxido de Carbono/análise , Meio Ambiente , Nigéria , Incerteza
9.
JAMA Otolaryngol Head Neck Surg ; 142(2): 138-42, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26720201

RESUMO

IMPORTANCE: Topical mupirocin therapy is used to treat symptomatic chronic sinusitis (CRS). However, the potential adverse impact of this therapy on the sinus microbiota has not been well quantified. OBJECTIVE: To determine changes in microbiologic culture results before and after topical mupirocin therapy in patients with CRS with medically and surgically refractory disease. DESIGN, SETTING, AND PARTICIPANTS: We performed a retrospective medical chart review for 22 consecutive adults evaluated and treated between January 1, 2012, and January 1, 2014, at an otolaryngology-rhinology clinic at a regional academic medical center. The patients were 14 men and 8 women, who had undergone functional endoscopic sinus surgery for CRS, and in whom sinus aspirate cultures were performed before and after topical mupirocin therapy for symptomatic disease. Analyses were performed in April 2014. EXPOSURES: Patients underwent treatment with saline sinus rinse, with the addition of mupirocin, for at least 1 week. MAIN OUTCOMES AND MEASURES: Bacterial isolates from sinus aspirate culture. RESULTS: The patients included 14 men and 8 women, 18 to 75 years old, who underwent a mean of 1.9 functional endoscopic sinus surgical procedures. The mean (range) duration of mupirocin therapy was 6 (2-12) weeks. Before mupirocin therapy, cultures from symptomatic patients (14 men and 8 women, ages 18-75 years) revealed common bacteria implicated in CRS, which are characteristically gram-positive. After mupirocin therapy, cultures from symptomatic patients shifted significantly: 19 were gram-positive vs 3 gram-negative before treatment; 9 were gram-positive vs 13 gram-negative after treatment (P = .004), with increased growth of pathogenic gram-negative bacteria and Corynebacterium. CONCLUSIONS AND RELEVANCE: These data present evidence supporting the distinct abrogation of culturable sinus bacteria after mupirocin rinses, identifying a shift toward increased pathogenic bacteria. Consideration of healthy host microbiome and immune dysfunction should guide future treatment considerations.


Assuntos
Antibacterianos/uso terapêutico , Mupirocina/uso terapêutico , Rinite/tratamento farmacológico , Rinite/microbiologia , Sinusite/tratamento farmacológico , Sinusite/microbiologia , Administração Tópica , Adolescente , Adulto , Idoso , Antibacterianos/administração & dosagem , Doença Crônica , Terapia Combinada , Endoscopia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mupirocina/administração & dosagem , Estudos Retrospectivos , Rinite/cirurgia , Sinusite/cirurgia , Resultado do Tratamento
10.
Dev Psychol ; 41(6): 833-50, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16351331

RESUMO

The employment rate for mothers with young children has increased dramatically over the past 25 years. Estimating the effects of maternal employment on children's development is challenged by selection bias and the missing data endemic to most policy research. To address these issues, this study uses propensity score matching and multiple imputation. The authors compare outcomes across 4 maternal employment patterns: no work in first 3 years postbirth, work only after 1st year, part-time work in 1st year, and full-time work in 1st year. Our results demonstrate small but significant negative effects of maternal employment on children's cognitive outcomes for full-time employment in the 1st year postbirth as compared with employment postponed until after the 1st year. Multiple imputation yields noticeably different estimates as compared with a complete case approach for many measures. Differences between results from propensity score approaches and regression modeling are often minimal.


Assuntos
Desenvolvimento Infantil , Relações Mãe-Filho , Mulheres Trabalhadoras/psicologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Inteligência , Controle Interno-Externo , Masculino , Avaliação de Resultados em Cuidados de Saúde , Desenvolvimento da Personalidade
11.
Dev Psychol ; 39(4): 730-744, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12859126

RESUMO

Effects of high participation in the Infant Health and Development Program (IHDP), an 8-site randomized trial that targeted low-birth-weight (LBW) premature infants (N=1,082), were estimated. Children in the treatment group were offered high-quality center-based care in their 2nd and 3rd years of life (full-day care, 50 weeks per year). High-dosage effects were estimated with a new methodology that found a matched comparison group within the follow-up group for those with high participation rates; these estimates were compared with traditional intention-to-treat (ITT) estimates. At age 8, effects on the Wechsler Intelligence Scale for Children Full and Verbal scales for children who attended > 400 days ranged from 7 to 10 points. For the heavier LBW infants (2,001-2,500 g), the effects were about 14 points for > 400 days; for the lighter LBW infants (< or = 2,000 g), the effects were about 8 points. These effects were all substantially higher than corresponding ITT effects. Similar but smaller effects were found for children who attended > 350 days.


Assuntos
Intervenção Educacional Precoce/estatística & dados numéricos , Recém-Nascido de Baixo Peso/psicologia , Recém-Nascido Prematuro/psicologia , Inteligência/classificação , Desenvolvimento da Linguagem , Peso ao Nascer , Criança , Pré-Escolar , Interpretação Estatística de Dados , Feminino , Seguimentos , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos , Fatores Socioeconômicos
12.
J Environ Qual ; 31(4): 1286-93, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12175048

RESUMO

Regulatory agencies are interested in a fecal indicator bacterium with a host range limited to humans because human fecal contamination represents the greatest hazard to humans, yet is a relatively easy nonpoint source to remedy. Watersheds with human fecal contamination could be given first priority for cleanup. A fecal indicator bacterium with a host range limited to humans and a few other warm-blooded animal species would also simplify microbial source tracking because only a few animal species would be required for any host origin database. The literature suggests that the fecal indicator bacterium Enterococcus faecalis has a limited host range. On this basis, we selected this bacterium for study. Of 583 fecal streptococcal isolates obtained on Enterococcosel agar from Canada goose, cattle, deer, dog, human, chicken, and swine, 392 were considered presumptive enterococci and were subsequently speciated with the API 20 Strep system. Of these isolates, 22 were Ent. durans (5.6%), 61 were Ent. faecalis (15.6%), 98 were Ent. faecium (25.0%), 86 were Ent. gallinarum (21.9%), and 125 were unidentified (31.9%). The host range of the Ent. faecalis isolates was limited to dogs, humans, and chickens. Media were developed to isolate and identify Ent. faecalis quickly from fecal samples and this scheme eliminated Ent. faecalis isolates from dogs. When the remaining Ent. faecalis isolates were ribotyped, it was possible to differentiate clearly among the isolates from human and chicken. It may be that combining the potentially limited host range of Ent. faecalis with ribotyping is useful for prioritizing watersheds with fecal contamination.


Assuntos
Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Monitoramento Ambiental/métodos , Ribotipagem , Microbiologia da Água , Poluentes da Água/análise , Animais , Animais Domésticos , Biomarcadores , Cães , Fezes/microbiologia , Humanos , Sensibilidade e Especificidade
13.
J Environ Qual ; 31(4): 1273-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12175046

RESUMO

Several genotypic methods have been developed for determining the host origin of fecal bacteria in contaminated waters. Some of these methods rely on a host origin database to identify environmental isolates. It is not well understood to what degree these host origin isolates are geographically variable (i.e., cosmopolitan or endemic). This is important because a geographically limited host origin database may or may not be universally applicable. The objective of our study was to use one genotypic method, ribotyping, to determine the geographic variability of the fecal bacterium, Escherichia coli, from one location in Idaho and three locations in Georgia for cattle (Bos taurus), horse (Equus caballus), swine (Sus scrofa), and chicken (Gallus gallus domesticus). A total of 568 fecal E. coli isolates from Kimberly, ID (125 isolates), Athens, GA (210 isolates), Brunswick, GA (102 isolates), and Tifton, GA (131 isolates), yielded 213 ribotypes. The percentage of ribotype sharing within an animal species increased with decreased distance between geographic locations for cattle and horses, but not for swine and chicken. When the E. coli ribotypes among the four host species were compared at one location, the percent of unshared ribotypes was 86, 89, 81, and 79% for Kimberly, Athens, Brunswick, and Tifton, respectively. These data suggest that there is good ribotype separation among host animal species at each location. The ability to match environmental isolates to a host origin database may depend on a large number of environmental and host origin isolates that ideally are not geographically separated.


Assuntos
Escherichia coli/genética , Variação Genética , Ribotipagem , Animais , Bovinos/microbiologia , Galinhas/microbiologia , Bases de Dados Factuais , Escherichia coli/patogenicidade , Genótipo , Geografia , Georgia , Cavalos/microbiologia , Idaho , Suínos/microbiologia
15.
J Opt Soc Am A Opt Image Sci Vis ; 20(5): 817-26, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12747429

RESUMO

We explore the use of Cramér-Rao bound calculations for predicting fundamental limits on the accuracy with which target characteristics can be determined by using imaging sensors. In particular, estimation of satellite orientation from high-resolution sensors is examined. The analysis role that such bounds provide for sensor/experiment design, operation, and upgrade is discussed. Emphasis is placed on the importance of including all relevant target/sensor uncertainties in the analysis. Computer simulations are performed that illustrate that uncertainties in target features (e.g., shape, reflectance, and relative orientation) have a significant impact on the bounds and provide considerable insight as to how details of the three-dimensional target structure may influence the estimation process. The simulations also address the impact that a priori information has on the bounds.

16.
J Strength Cond Res ; 18(3): 426-31, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15320672

RESUMO

Few studies have examined fast-pitch softball pitchers and associated injuries. The aim of this study was to investigate injuries occurring to collegiate softball pitchers and associated influential factors. A web-based survey of 181 Division I (n = 45), II (n = 30), and III (n = 54) collegiate softball pitchers was conducted. The survey involved self-reported data from the previous year that addressed (a) demographic information, (b) pitching and game data, (c) training program information, and (d) injury reporting. Demographic information, pitching and game data, and training program information were not statistically significant (p < 0.05) in relation to injury. Descriptive statistics were used to report totals and percentages of pitchers surveyed. Among 131 reported injuries, 36 were acute, 92 chronic/overuse, and 3 unspecified. Of the total injuries, 80 were directly from pitching, with 33 shoulder-related and 16 related to the lower back. Among injured pitchers, 109 took nonsteroidal anti-inflammatory drugs, 140 used modalities, 11 received surgeries, and 95 saw additional specialists. Pitchers are at a risk for injury, with 72.8% of surveyed pitchers being injured during the 2001-02 year.


Assuntos
Traumatismos em Atletas/epidemiologia , Beisebol/lesões , Beisebol/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Anti-Inflamatórios não Esteroides/uso terapêutico , Traumatismos em Atletas/terapia , Tamanho Corporal , Transtornos Traumáticos Cumulativos/epidemiologia , Transtornos Traumáticos Cumulativos/terapia , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Músculo Esquelético/lesões , Fatores de Risco , Medicina Esportiva/métodos , Medicina Esportiva/estatística & dados numéricos , Traumatismos dos Tendões/epidemiologia , Traumatismos dos Tendões/terapia , Estados Unidos/epidemiologia
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