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1.
J Pediatr ; 267: 113901, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38181978

RESUMO

OBJECTIVES: To evaluate patterns and determinants of longitudinal growth among children requiring complex biventricular repair for congenital heart disease, as well as to assess for associations of growth with early feeding modality, comorbidities, postoperative complications, and socioeconomic characteristics. STUDY DESIGN: A single-institution retrospective cohort study was performed in children born February 1999 to March 2009 with complex congenital heart disease who underwent biventricular repair before age 4 years, defined by Risk Adjustment in Congenital Heart Surgery-1 category 3-5. Clinical characteristics, height, weight, and body mass index (BMI) from ages 2-12 years were collected by chart review. Neighborhood-level socioeconomic data were identified using a geographic information system approach. The adjusted association of covariates with growth outcomes was estimated using multivariable linear regression models using generalized estimating equations. RESULTS: Compared with population growth curves, the cohort (n = 150) trended toward early decrease in age-adjusted weight and height. Early tube feeding was significantly associated with decreased BMI before adolescence (-0.539; 95% CI -1.02, -0.054; P = .029). In addition, other clinical and perioperative characteristics had significant associations with growth, including low birth weight, preoperative tube feeds, need for multiple bypass runs, and diagnosis of feeding disorder. CONCLUSIONS: Early childhood growth in children with complex biventricular repair may be impaired. Early tube feeding was associated with decreased BMI over the course of early childhood, which may indicate a need for continued close nutrition follow-up and support even beyond the duration of tube feeds.


Assuntos
Nutrição Enteral , Cardiopatias Congênitas , Criança , Adolescente , Humanos , Pré-Escolar , Lactente , Estudos Retrospectivos , Índice de Massa Corporal , Estado Nutricional , Cardiopatias Congênitas/cirurgia
2.
Sensors (Basel) ; 23(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36991856

RESUMO

Of particular interest within fifth generation (5G) cellular networks are the typical levels of radiofrequency (RF) electromagnetic fields (EMFs) emitted by 'small cells', low-power base stations, which are installed such that both workers and members of the general public can come in close proximity with them. In this study, RF-EMF measurements were performed near two 5G New Radio (NR) base stations, one with an Advanced Antenna System (AAS) capable of beamforming and the other a traditional microcell. At various positions near the base stations, with distances ranging between 0.5 m and 100 m, both the worst-case and time-averaged field levels under maximized downlink traffic load were assessed. Moreover, from these measurements, estimates were made of the typical exposures for various cases involving users and non-users. Comparison to the maximum permissible exposure limits issued by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) resulted in maximum exposure ratios of 0.15 (occupational, at 0.5 m) and 0.68 (general public, at 1.3 m). The exposure of non-users was potentially much lower, depending on the activity of other users serviced by the base station and its beamforming capabilities: 5 to 30 times lower in the case of an AAS base station compared to barely lower to 30 times lower for a traditional antenna.


Assuntos
Telefone Celular , Campos Eletromagnéticos , Humanos , Exposição Ambiental , Ondas de Rádio/efeitos adversos
3.
J Pediatr ; 231: 124-130.e1, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33359473

RESUMO

OBJECTIVE: To evaluate the effect of a standardized feeding approach using a clinical nutrition pathway on weight-for-age Z score (WAZ) over hospital length of stay (HLOS) for infants with congenital heart disease (CHD). STUDY DESIGN: A 10-year retrospective cohort study examined eligible infants who underwent neonatal cardiac surgery between July 2009 and December 2018 (n = 987). Eligibility criteria included infants born at least 37 weeks of gestation and a minimum birth weight of 2 kg who underwent cardiac surgery for CHD within the first 30 days of life. Using the best linear unbiased predictions from a linear mixed effects model, WAZ change over HLOS was estimated before and after January 2013, when the standardized feeding approach was initiated. The best linear unbiased predictions model included adjustment for patient characteristics including sex, race, HLOS, and class of cardiac defect. RESULTS: The change in WAZ over HLOS was significantly higher from 2013 to 2018 than from 2009 to 2012 (ß = 0.16; SE = 0.02; P < .001), after controlling for sex, race, HLOS, and CHD category, indicating that infants experienced a decreased WAZ loss over HLOS after the standardized feeding approach was initiated. Additionally, differences were found in WAZ loss over HLOS between infants with single ventricle CHD (ß = 0.26; SE = 0.04; P < .001) and 2 ventricle CHD (ß = 0.04; SE = 0.02; P = .04). CONCLUSIONS: These data suggest that an organized, focused approach for nutrition therapy using a standardized pathway improves weight change outcomes before hospital discharge for infants with single and 2 ventricle CHD who require neonatal cardiac surgery.


Assuntos
Cardiopatias Congênitas/cirurgia , Terapia Nutricional/normas , Assistência Perioperatória/normas , Aumento de Peso , Redução de Peso , Procedimentos Clínicos , Feminino , Cardiopatias Congênitas/fisiopatologia , Hospitalização , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Modelos Logísticos , Masculino , Terapia Nutricional/métodos , Assistência Perioperatória/métodos , Estudos Retrospectivos , Resultado do Tratamento
4.
Brain Cogn ; 123: 142-153, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29573702

RESUMO

The present research assessed how engaging in bilateral eye movements influences brain activity. Participants had their resting-state brain activity recorded with electroencephalography (EEG) before and after they performed 30 s of bilateral eye movements or a center-control manipulation. We assessed differences in change scores for absolute power and coherence between the eye-movement and center-control conditions. A main effect for handedness was present for EEG power in the theta and beta frequency bands, with inconsistent-handed participants displaying a greater increase than consistent-handed participants in both frequency bands. For theta, the increase in power for inconsistent handers was specific to participants in the bilateral eye-movement condition, whose increase in theta power exceeded the increase in theta power for consistent-handed participants regardless of condition. In contrast, for coherence, a main effect for condition was present for the delta frequency band, with participants in the control condition exhibiting a significant drop in posterior delta coherence pre to post. We suggest that the maintenance of posterior delta coherence over time may be an important factor in sustaining attention. Further, the malleability of EEG power for inconsistent-handed participants reveals the importance of individual-differences variables in the potential for behavioral manipulations to change brain activity.


Assuntos
Encéfalo/fisiologia , Movimentos Oculares/fisiologia , Rede Nervosa/fisiologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Individualidade , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Psychol Rep ; 116(3): 983-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25933046

RESUMO

The yearly suicide rates for the period 1933-2010 and the daily suicide numbers for 1990 and 1991 were examined for whether the distribution of difference scores (from year to year and from day to day) fitted a normal distribution, a characteristic of stochastic processes that follow a random walk. If the suicide rate were a random walk, then any disturbance to the suicide rate would have a permanent effect and national suicide prevention efforts would likely fail. The distribution of difference scores from day to day (but not the difference scores from year to year) fitted a normal distribution and, therefore, were consistent with a random walk.


Assuntos
Distribuição Normal , Suicídio/estatística & dados numéricos , Humanos , Estados Unidos/epidemiologia
6.
J Res Educ Eff ; 17(1): 184-210, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450254

RESUMO

Multi-site randomized controlled trials (RCTs) provide unbiased estimates of the average impact in the study sample. However, their ability to accurately predict the impact for individual sites outside the study sample, to inform local policy decisions, is largely unknown. To extend prior research on this question, we analyzed six multi-site RCTs and tested modern prediction methods-lasso regression and Bayesian Additive Regression Trees (BART)-using a wide range of moderator variables. The main study findings are that: (1) all of the methods yielded accurate impact predictions when the variation in impacts across sites was close to zero (as expected); (2) none of the methods yielded accurate impact predictions when the variation in impacts across sites was substantial; and (3) BART typically produced "less inaccurate" predictions than lasso regression or than the Sample Average Treatment Effect. These results raise concerns that when the impact of an intervention varies considerably across sites, statistical modelling using the data commonly collected by multi-site RCTs will be insufficient to explain the variation in impacts across sites and accurately predict impacts for individual sites.

7.
Environ Toxicol Chem ; 29(5): 1049-55, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20821539

RESUMO

The resuspension of large volumes of sediments that are contaminated with chlorinated pollutants continues to threaten environmental quality and human health. Whereas kinetic models are more accurate for estimating the environmental impact of these events, their widespread use is substantially hampered by the need for costly, time-consuming, site-specific kinetics experiments. The present study investigated the development of a predictive model for desorption rates from easily measurable sorbent and pollutant properties by examining the relationship between the fraction of organic carbon (fOC) and labile release rates. Duplicate desorption measurements were performed on 46 unique combinations of pollutants and sorbents with fOC values ranging from 0.001 to 0.150. Labile desorption rate constants indicate that release rates predominantly depend upon the fOC in the geosorbent. Previous theoretical models, such as the macro-mesopore and organic matter (MOM) diffusion model, have predicted such a relationship but could not accurately predict the experimental rate constants collected in the present study. An empirical model was successfully developed to correlate the labile desorption rate constant (krap) to the fraction of organic material where log(krap)=0.291-0.785 . log(fOC). These results provide the first experimental evidence that kinetic pollution releases during resuspension events are governed by the fOC content in natural geosorbents.


Assuntos
Carbono/química , Dieldrin/química , Sedimentos Geológicos/química , Poluentes Químicos da Água/química , Adsorção , Modelos Biológicos , Solo , Fatores de Tempo
8.
Pediatr Qual Saf ; 5(2): e260, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32426627

RESUMO

INTRODUCTION: In many centers, children with diabetic ketoacidosis (DKA) receive care either in an endocrinology ward or a pediatric intensive care unit (PICU). We conducted a quality improvement (QI) initiative to reduce potentially avoidable PICU admissions of children with DKA without increasing endocrinology ward-to-PICU transfers. METHODS: A survey of providers demonstrated opportunities to increase awareness of institutional criteria for PICU admissions of children with DKA. We created an electronic health record (EHR) dot-phrase, prepopulated with these criteria, and placed a note in the EHR for all patients with DKA as a reference for all providers. An EHR-based data report was created to monitor the disposition of DKA patients and the use of the dot-phrase (process measure). The primary outcome measure was the potentially avoidable PICU admissions for patients with DKA. Endocrinology ward-to-PICU transfers were tracked as a balancing measure to ensure safe disposition. RESULTS: After the implementation of the dot-phrase, use was variable, but averaged 33.4% over 1 year. The percentage of DKA admissions classified as potentially avoidable PICU stays decreased from 4.1% to 0.5%, with a concurrent decrease in the total percentage of PICU admissions for DKA from 19.1% to 8.4%. The percentage of endocrinology ward-to-PICU transfers also declined from 0.8% to 0%. CONCLUSIONS: A novel EHR-based intervention increasing awareness and documentation of established pediatric DKA management guidelines can be used to safely reduce PICU admissions for DKA without increasing the rate of endocrinology ward-to-intensive care unit transfers.

9.
Artigo em Inglês | MEDLINE | ID: mdl-19227075

RESUMO

Experiments and computer simulations were conducted to systematically investigate the influence of mashed potato dielectric properties and circulating water electric conductivity on electromagnetic field distribution, heating rate, and heating pattern in packaged food during radio frequency (RF) heating processes in a 6 kW, 27 MHz laboratory scale RF heating system. Both experimental and simulation results indicated that for the selected food (mashed potato) in this study, the heating rate decreased with an increase of electric conductivity of circulating water and food salt content. Simplified analytical calculations were carried out to verify the simulation results, which further indicated that the electric field distribution in the mashed potato samples was also influenced by their dielectric properties and the electric conductivity of the surrounding circulating water. Knowing the influence of water electric conductivity and mashed potato dielectric properties on the heating rate and heating pattern is helpful in optimizing the radio frequency heating process by properly adjusting these factors. The results demonstrate that computer simulation has the ability to demonstrate influence on RF heat pattern caused by the variation of material physical properties and the potential to aid the improvement on construction and modification of RF heating systems.


Assuntos
Manipulação de Alimentos , Calefação , Ondas de Rádio , Solanum tuberosum , Água/química , Simulação por Computador , Condutividade Elétrica , Conservação de Alimentos , Sais
10.
J Res Educ Eff ; 10(1): 168-206, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29276552

RESUMO

Given increasing interest in evidence-based policy, there is growing attention to how well the results from rigorous program evaluations may inform policy decisions. However, little attention has been paid to documenting the characteristics of schools or districts that participate in rigorous educational evaluations, and how they compare to potential target populations for the interventions that were evaluated. Utilizing a list of the actual districts that participated in 11 large-scale rigorous educational evaluations, we compare those districts to several different target populations of districts that could potentially be affected by policy decisions regarding the interventions under study. We find that school districts that participated in the 11 rigorous educational evaluations differ from the interventions' target populations in several ways, including size, student performance on state assessments, and location (urban/rural). These findings raise questions about whether, as currently implemented, the results from rigorous impact studies in education are likely to generalize to the larger set of school districts-and thus schools and students-of potential interest to policymakers, and how we can improve our study designs to retain strong internal validity while also enhancing external validity.

11.
Front Public Health ; 4: 52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27066469

RESUMO

Conclusions of epidemiological studies describing adverse health effects as a result of exposure to electromagnetic fields are not unanimous and often contradictory. It has been proposed that an explanation could be that high-frequency voltage transients [dirty electricity (DE)] which are superimposed on 50/60-Hz fields, but are generally not measured, are the real causal agent. DE has been linked to many different health and wellbeing effects, and on the basis of this, an industry selling measurement and filtering equipment is growing. We reviewed the available peer-reviewed evidence for DE as a causal agent for adverse human health effects. A literature search was performed in the Cochrane Library, PubMed, Web of Science, Google Scholar, and additional publications were obtained from reference lists and from the gray literature. This search resulted in 25 publications; 16 included primary epidemiological and/or exposure data. All studies were reviewed by both authors independently, and including a re-review of studies included in a review of data available up to July 31, 2009 by one of the authors. DE has been measured differently in different studies and comparison data are not available. There is no evidence for 50 Graham/Stetzer (GS) units as a safety threshold being anything more than arbitrary. The epidemiological evidence on human health effects of DE is primarily based on, often re-used, case descriptions. Quantitative evidence relies on self-reporting in non-blinded interventions, ecological associations, and one cross-sectional cohort study of cancer risk, which does not point to DE as the causal agent. The available evidence for DE as an exposure affecting human health at present does not stand up to scientific scrutiny.

12.
J Policy Anal Manage ; 32(1): 107-121, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25152557

RESUMO

Evaluations of the impact of social programs are often carried out in multiple "sites," such as school districts, housing authorities, local TANF offices, or One-Stop Career Centers. Most evaluations select sites purposively following a process that is nonrandom. Unfortunately, purposive site selection can produce a sample of sites that is not representative of the population of interest for the program. In this paper, we propose a conceptual model of purposive site selection. We begin with the proposition that a purposive sample of sites can usefully be conceptualized as a random sample of sites from some well-defined population, for which the sampling probabilities are unknown and vary across sites. This proposition allows us to derive a formal, yet intuitive, mathematical expression for the bias in the pooled impact estimate when sites are selected purposively. This formula helps us to better understand the consequences of selecting sites purposively, and the factors that contribute to the bias. Additional research is needed to obtain evidence on how large the bias tends to be in actual studies that select sites purposively, and to develop methods to increase the external validity of these studies.

13.
J Phys Chem A ; 109(9): 1873-8, 2005 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16833519

RESUMO

The mechanism of Lengyel, Li, Kustin, and Epstein (J. Am. Chem. Soc. 1996, 118, 3708) for the oscillatory chlorine dioxide-iodide reaction accurately models the reaction in closed and open systems. We investigated whether this mechanism minus the single reaction involving chlorine dioxide models the chlorite-iodide reaction equally well. It agrees qualitatively with clock reaction results. As for open system dynamics, the mechanism predicts the existence of two steady states and bistability in very nearly the same regions where these features are found experimentally in the pH range 2-4. A discrepancy in the range of bistability emerges as pH decreases, and it cannot be remedied by taking into account chlorous acid decomposition. That we were unable to locate an oscillatory region is of greater significance. Because the chlorite-iodide reaction is sensitive to mixing effects, we incorporated a two-parameter model of imperfect mixing but still found no oscillations at physically reasonable parameter values. These discrepancies strongly suggest that to obtain predictive utility for the chlorite-iodide reaction, revision of the chlorine dioxide-iodide mechanism is required.

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