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1.
Resusc Plus ; 17: 100515, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38094660

RESUMEN

Aim: Neonatal resuscitation guidelines promote the laryngeal mask (LM) interface for positive pressure ventilation (PPV), but little is known about how the LM is used among Neonatal Resuscitation Program (NRP) Providers and Instructors. The study aim was to characterize the training, experience, confidence, and perspectives of NRP Providers and Instructors regarding LM use during neonatal resuscitation at birth. Methods: A voluntary anonymous survey was emailed to all NRP Providers and Instructors. Survey items addressed training, experience, confidence, and barriers for LM use during resuscitation. Associations between respondent characteristics and outcomes of both LM experience and confidence were assessed using logistic regression. Results: Between 11/7/22-12/12/22, there were 5,809 survey respondents: 68% were NRP Providers, 55% were nurses, and 87% worked in a hospital setting. Of these, 12% had ever placed a LM during newborn resuscitation, and 25% felt very or completely confident using a LM. In logistic regression, clinical or simulated hands-on training, NRP Instructor role, professional role, and practice setting were all associated with both LM experience and confidence.The three most frequently identified barriers to LM use were insufficient experience (46%), preference for other interfaces (25%), and failure to consider the LM during resuscitation (21%). One-third (33%) reported that LMs are not available where they resuscitate newborns. Conclusion: Few NRP providers and instructors use the LM during neonatal resuscitation. Strategies to increase LM use include hands-on clinical training, outreach promoting the advantages of the LM compared to other interfaces, and improving availability of the LM in delivery settings.

2.
Pediatr Blood Cancer ; : e30474, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37283294

RESUMEN

BACKGROUND: Clinical informatics tools to integrate data from multiple sources have the potential to catalyze population health management of childhood cancer survivors at high risk for late heart failure through the implementation of previously validated risk calculators. METHODS: The Oklahoma cohort (n = 365) harnessed data elements from Passport for Care (PFC), and the Duke cohort (n = 274) employed informatics methods to automatically extract chemotherapy exposures from electronic health record (EHR) data for survivors 18 years old and younger at diagnosis. The Childhood Cancer Survivor Study (CCSS) late cardiovascular risk calculator was implemented, and risk groups for heart failure were compared to the Children's Oncology Group (COG) and the International Guidelines Harmonization Group (IGHG) recommendations. Analysis within the Oklahoma cohort assessed disparities in guideline-adherent care. RESULTS: The Oklahoma and Duke cohorts both observed good overall concordance between the CCSS and COG risk groups for late heart failure, with weighted kappa statistics of .70 and .75, respectively. Low-risk groups showed excellent concordance (kappa > .9). Moderate and high-risk groups showed moderate concordance (kappa .44-.60). In the Oklahoma cohort, adolescents at diagnosis were significantly less likely to receive guideline-adherent echocardiogram surveillance compared with survivors younger than 13 years old at diagnosis (odds ratio [OD] 0.22; 95% confidence interval [CI]: 0.10-0.49). CONCLUSIONS: Clinical informatics tools represent a feasible approach to leverage discrete treatment-related data elements from PFC or the EHR to successfully implement previously validated late cardiovascular risk prediction models on a population health level. Concordance of CCSS, COG, and IGHG risk groups using real-world data informs current guidelines and identifies inequities in guideline-adherent care.

3.
Cancer Epidemiol Biomarkers Prev ; 32(5): 634-641, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36827210

RESUMEN

BACKGROUND: Children with cancer from rural and nonurban areas face unique challenges. Health equity for this population requires attention to geographic disparities in optimal survivorship-focused care. METHODS: The Oklahoma Childhood Cancer Survivor Cohort was based on all patients reported to the institutional cancer registry and ≤ 18 years old at diagnosis between January 1, 2005, and September 24, 2014. Suboptimal follow-up was defined as no completed oncology-related clinic visit five to 7 years after their initial diagnosis (survivors were 7-25 years old at end of the follow-up period). The primary predictor of interest was rurality. RESULTS: Ninety-four (21%) of the 449 eligible survivors received suboptimal follow-up. There were significant differences (P = 0.01) as 36% of survivors from large towns (n = 28/78) compared with 21% (n = 20/95) and 17% (n = 46/276) of survivors from small town/isolated rural and urban areas received suboptimal follow-up, respectively. Forty-five percent of adolescents at diagnosis were not seen in the clinic compared with 17% of non-adolescents (P < 0.01). An adjusted risk ratio of 2.2 (95% confidence interval, 1.5, 3.2) was observed for suboptimal follow-up among survivors from large towns, compared with survivors from urban areas. Seventy-three percent of survivors (n = 271/369) had a documented survivorship care plan with similar trends by rurality. CONCLUSIONS: Survivors from large towns and those who were adolescents at the time of diagnosis were more likely to receive suboptimal follow-up care compared with survivors from urban areas and those diagnosed younger than thirteen. IMPACT: Observed geographic disparities in survivorship care will inform interventions to promote equitable care for survivors from nonurban areas.


Asunto(s)
Supervivientes de Cáncer , Neoplasias , Humanos , Niño , Adolescente , Adulto Joven , Adulto , Supervivencia , Ciudades , Estudios de Seguimiento , Neoplasias/terapia , Neoplasias/epidemiología , Población Rural
4.
PLoS One ; 18(1): e0279968, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36603014

RESUMEN

BACKGROUND: While COVID-19 vaccines reduce adverse outcomes, post-vaccination SARS-CoV-2 infection remains problematic. We sought to identify community factors impacting risk for breakthrough infections (BTI) among fully vaccinated persons by rurality. METHODS: We conducted a retrospective cohort study of US adults sampled between January 1 and December 20, 2021, from the National COVID Cohort Collaborative (N3C). Using Kaplan-Meier and Cox-Proportional Hazards models adjusted for demographic differences and comorbid conditions, we assessed impact of rurality, county vaccine hesitancy, and county vaccination rates on risk of BTI over 180 days following two mRNA COVID-19 vaccinations between January 1 and September 21, 2021. Additionally, Cox Proportional Hazards models assessed the risk of infection among adults without documented vaccinations. We secondarily assessed the odds of hospitalization and adverse COVID-19 events based on vaccination status using multivariable logistic regression during the study period. RESULTS: Our study population included 566,128 vaccinated and 1,724,546 adults without documented vaccination. Among vaccinated persons, rurality was associated with an increased risk of BTI (adjusted hazard ratio [aHR] 1.53, 95% confidence interval [CI] 1.42-1.64, for urban-adjacent rural and 1.65, 1.42-1.91, for nonurban-adjacent rural) compared to urban dwellers. Compared to low vaccine-hesitant counties, higher risks of BTI were associated with medium (1.07, 1.02-1.12) and high (1.33, 1.23-1.43) vaccine-hesitant counties. Compared to counties with high vaccination rates, a higher risk of BTI was associated with dwelling in counties with low vaccination rates (1.34, 1.27-1.43) but not medium vaccination rates (1.00, 0.95-1.07). Community factors were also associated with higher odds of SARS-CoV-2 infection among persons without a documented vaccination. Vaccinated persons with SARS-CoV-2 infection during the study period had significantly lower odds of hospitalization and adverse events across all geographic areas and community exposures. CONCLUSIONS: Our findings suggest that community factors are associated with an increased risk of BTI, particularly in rural areas and counties with high vaccine hesitancy. Communities, such as those in rural and disproportionately vaccine hesitant areas, and certain groups at high risk for adverse breakthrough events, including immunosuppressed/compromised persons, should continue to receive public health focus, targeted interventions, and consistent guidance to help manage community spread as vaccination protection wanes.


Asunto(s)
COVID-19 , Humanos , Adulto , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Estudios Retrospectivos , SARS-CoV-2 , Infección Irruptiva , Vacunación
5.
Am J Perinatol ; 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36452967

RESUMEN

OBJECTIVE: The U.S. opioid epidemic has been characterized by increases in opioid misuse, overdose deaths, and neonatal opioid withdrawal syndrome. Research suggests that marijuana legalization has contributed to decreased use of opiates, although many studies had methodological weaknesses and failed to address the pregnant population. Implementation of medical cannabis laws has the potential to reduce maternal opioid use and, therefore, neonatal exposure to the drugs. This study aimed to examine the association between Oklahoma's implementation of state medical marijuana laws and the neonatal exposure to opioids. STUDY DESIGN: Electronic medical records at two sites (Oklahoma City and Lawton) were searched for results of cord, urine, and meconium screens to detect amphetamines, barbiturates, benzodiazepines, cocaine, ethanol, opiates, phencyclidine, and tetrahydrocannabinol (THC). Two study periods were compared: 19 months before Oklahoma's medical marijuana law took effect and 19 months after legalization began. RESULTS: A total of 16,804 babies were born alive at the two sites during the study period. The rate of positive THC tests per 1,000 liveborn infants significantly increased from 16.2 per 1,000 during the prelaw period to 22.2 per 1,000 during the postlaw period (p = 0.004). Neonatal opioid exposure incidence showed a nonsignificant decrease from 7.6 positive tests per 1,000 liveborn infants to 6.8 per 1,000 from prelaw to postlaw period (p = 0.542). The number of positive tests for THC and concomitant use of opioids doubled from the prelaw period (n = 4) to postlaw (n = 9), but there were too few cases for statistical significance. Infants at the more rural site had significantly higher rates for amphetamines, benzodiazepines, and THC, with a trend toward higher rates for opiates. CONCLUSION: Marijuana legalization was related to significant increases in positive test rates for THC, but no significant change/association was noted for neonatal exposure to opioids. KEY POINTS: · Prior studies have not examined neonatal exposure to opioids following marijuana legalization.. · Oklahoma's new law led to higher neonatal marijuana exposure.. · Legalization of medical marijuana did not change Oklahoma's neonatal opioid positivity rate..

6.
J Rural Health ; 39(1): 39-54, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35758856

RESUMEN

PURPOSE: Rural communities are among the most underserved and resource-scarce populations in the United States. However, there are limited data on COVID-19 outcomes in rural America. This study aims to compare hospitalization rates and inpatient mortality among SARS-CoV-2-infected persons stratified by residential rurality. METHODS: This retrospective cohort study from the National COVID Cohort Collaborative (N3C) assesses 1,033,229 patients from 44 US hospital systems diagnosed with SARS-CoV-2 infection between January 2020 and June 2021. Primary outcomes were hospitalization and all-cause inpatient mortality. Secondary outcomes were utilization of supplemental oxygen, invasive mechanical ventilation, vasopressor support, extracorporeal membrane oxygenation, and incidence of major adverse cardiovascular events or hospital readmission. The analytic approach estimates 90-day survival in hospitalized patients and associations between rurality, hospitalization, and inpatient adverse events while controlling for major risk factors using Kaplan-Meier survival estimates and mixed-effects logistic regression. FINDINGS: Of 1,033,229 diagnosed COVID-19 patients included, 186,882 required hospitalization. After adjusting for demographic differences and comorbidities, urban-adjacent and nonurban-adjacent rural dwellers with COVID-19 were more likely to be hospitalized (adjusted odds ratio [aOR] 1.18, 95% confidence interval [CI], 1.16-1.21 and aOR 1.29, CI 1.24-1.1.34) and to die or be transferred to hospice (aOR 1.36, CI 1.29-1.43 and 1.37, CI 1.26-1.50), respectively. All secondary outcomes were more likely among rural patients. CONCLUSIONS: Hospitalization, inpatient mortality, and other adverse outcomes are higher among rural persons with COVID-19, even after adjusting for demographic differences and comorbidities. Further research is needed to understand the factors that drive health disparities in rural populations.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Estados Unidos/epidemiología , COVID-19/epidemiología , COVID-19/terapia , Población Rural , Estudios Retrospectivos , Hospitalización
7.
J Telemed Telecare ; : 1357633X221104563, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35765233

RESUMEN

BACKGROUND: Managing critically ill neonates has unique challenges, and the transport team plays an important role in stabilizing and facilitating the transfer of these neonates from lower-level nurseries to tertiary centers, and the use of telemedicine in transport (tele-transport) can potentially benefit patient care. We conducted a multicenter study to assess the readiness for utilizing telemedicine as an adjunct to guide the care of critically ill neonates among physicians and transport team members (TTMs). This is the first multicenter study that explored physicians' and TTMs' perceptions of telemedicine usage and its value in neonatal transport. METHODS: A confidential, voluntary survey on pre-implementation attitudes toward telemedicine usage during neonatal transport was conducted as part of a quality improvement initiative. This survey involved physicians and TTMs from four academic institutions whose responses were entered into an online survey using REDCap®. The survey inquired about satisfaction with the current practice of phone consultation and the perception of using telemedicine to optimize the management of neonates during transport. RESULTS : The overall response rate for the survey was 60.1%; 82 of 127 (64.6%) physicians and 64 of 116 (55.2%) TTMs responded to the surveys. Half of the physicians and less than one-fourth of the TTMs had prior experience with telemedicine other than that used on neonatal transport. TTMs expressed greater concern about the inconvenience of video (55% vs. physicians 35% agree or strongly agree) and its time consumption (84% vs. physicians 50%). More than 70% of physicians and less than half of TTMs endorsed the potential for added value and quality improvement with video capability. Almost half of TTMs reported concern about video calls reducing their autonomy in patient care. Physicians expressed confidence in management decisions they would make after video calls (72% confident or very confident) and less confidence (49%) about both the phone assessment by TTMs and their decisions based on phone assessment. In contrast, TTMs were confident or very confident (94%) in both sharing their assessment over the phone and executing patient management after a phone call, compared with 70% for decisions made after video calls. CONCLUSIONS : Physicians and TTMs had distinct opinions on the use of telemedicine during neonatal transport. Physicians were more likely than TTMs to agree with statements about the potential for improving quality of care, while TTMs were more likely than physicians to say video calls would be time-consuming and inconvenient. We speculate some differences may stem from the TTMs' concern about losing their autonomy. Therefore, during implementation, it is critical for physicians and TTMs to agree on a shared mental model of indications for telemedicine during transport and its value to the patient care.

8.
J Infect Dis ; 225(5): 800-809, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-34865064

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) disproportionally affects pregnant women and their newborn; however, little is known about variables that modulate maternal-fetal immune response to infection. METHODS: We prospectively studied socioeconomic, biologic, and clinical factors affecting humoral immunity in 87 unvaccinated pregnant women hospitalized in Buenos Aires for symptoms consistent with COVID-19. RESULTS: The number of days between symptom onset and childbirth predicted maternal and newborn virus spike protein receptor binding domain (RBD)-specific immunoglobulin G (IgG). These findings suggest newborns may benefit less when mothers deliver soon after COVID-19 infection. Similarly, a longer time between symptom onset and birth predicted higher in utero transfer of maternal IgG and its concentration in cord blood. Older gestational age at birth was associated with lower maternal to cord blood IgG ratio. Of women with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, 87% developed RBD-specific IgA responses in breast milk within 96 hours of childbirth. IgA was not significantly associated with time from infection but correlated with maternal serum IgG and placental transfer. CONCLUSIONS: These results demonstrate the combined role of biologic, clinical, and socioeconomic variables associated with maternal RBD-specific antibodies and supports early vaccination strategies for COVID-19 in socioeconomically vulnerable pregnant women. CLINICAL TRIALS REGISTRATION: NCT04362956.


Asunto(s)
Anticuerpos Antivirales/sangre , COVID-19/inmunología , COVID-19/transmisión , Inmunoglobulina G/sangre , SARS-CoV-2/inmunología , Adulto , Productos Biológicos , COVID-19/sangre , Prueba Serológica para COVID-19 , Femenino , Humanos , Recién Nacido , Placenta/metabolismo , Embarazo , Estudios Prospectivos , Glicoproteína de la Espiga del Coronavirus/inmunología , Poblaciones Vulnerables
9.
Behav Genet ; 49(5): 444-454, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31392459

RESUMEN

In 1918, Fisher suggested that his research team had consistently found inflated cousin correlations. He also commented that because a cousin sample with minimal selection bias was not available the cause of the inflation could not be addressed, leaving this inflation as a challenge still to be solved. In the National Longitudinal Survey of Youth (the NLSY79, the NLSY97, and the NLSY-Children/Young Adult datasets), there are thousands of available cousin pairs. Those in the NLSYC/YA are obtained approximately without selection. In this paper, we address Fisher's challenge using these data. Further, we also evaluate the possibility of fitting ACE models using only cousin pairs, including full cousins, half-cousins, and quarter-cousins. To have any chance at success in such a restricted kinship domain requires an available and highly-reliable phenotype; we use adult height in our analysis. Results provide a possible answer to Fisher's challenge, and demonstrate the potential for using cousin pairs in a stand-alone analysis (as well as in combination with other biometrical designs).


Asunto(s)
Biometría , Estatura/genética , Familia , Femenino , Humanos , Estudios Longitudinales , Masculino , Adulto Joven
10.
J Gerontol A Biol Sci Med Sci ; 74(11): 1793-1804, 2019 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-30825374

RESUMEN

BACKGROUND: Substantial research is dedicated to understanding the aging-related dynamics among individual differences in level, change, and variation across physical and cognitive abilities. Evaluating replicability and synthesizing these findings has been limited by differences in measurements and samples, and by study design and statistical analyses confounding between-person differences with within-person changes. In this article, we conducted a coordinated analysis and summary meta-analysis of new results on the aging-related dynamics linking pulmonary function and cognitive performance. METHODS: We performed coordinated analysis of bivariate growth models in data from 20,586 participants across eight longitudinal studies to examine individual differences in baseline level, rate of change, and occasion-specific variability in pulmonary and cognitive functioning. Results were summarized using meta-analysis. RESULTS: We found consistent but weak baseline and longitudinal associations in levels of pulmonary and cognitive functioning, but no associations in occasion-specific variability. CONCLUSIONS: Results provide limited evidence for a consistent link between simultaneous changes in pulmonary and cognitive function in a normal aging population. Further research is required to understand patterns of onset of decline and differences in rates of change within and across physical and cognitive functioning domains, both within-individuals and across countries and birth cohorts. Coordinated analysis provides an efficient and rigorous approach for replicating and comparing results across independent longitudinal studies.


Asunto(s)
Envejecimiento/fisiología , Envejecimiento/psicología , Trastornos del Conocimiento/epidemiología , Enfermedades Pulmonares/epidemiología , Pruebas de Función Respiratoria , Factores de Edad , Anciano , Anciano de 80 o más Años , Trastornos del Conocimiento/fisiopatología , Comorbilidad , Femenino , Humanos , Estudios Longitudinales , Enfermedades Pulmonares/fisiopatología , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Prevalencia , Pronóstico , Medición de Riesgo , Factores Sexuales , Capacidad Vital
11.
Behav Genet ; 46(4): 538-51, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26914462

RESUMEN

The National Longitudinal Survey of Youth datasets (NLSY79; NLSY-Children/Young Adults; NLSY97) have extensive family pedigree information contained within them. These data sources are based on probability sampling, a longitudinal design, and a cross-generational and within-family data structure, with hundreds of phenotypes relevant to behavior genetic (BG) researchers, as well as to other developmental and family researchers. These datasets provide a unique and powerful source of information for BG researchers. But much of the information required for biometrical modeling has been hidden, and has required substantial programming effort to uncover-until recently. Our research team has spent over 20 years developing kinship links to genetically inform biometrical modeling. In the most recent release of kinship links from two of the NLSY datasets, the direct kinship indicators included in the 2006 surveys allowed successful and unambiguous linking of over 94 % of the potential pairs. In this paper, we provide details for research teams interested in using the NLSY data portfolio to conduct BG (and other family-oriented) research.


Asunto(s)
Bases de Datos como Asunto , Familia , Genética Conductual , Niño , Humanos , Estudios Longitudinales , Curva ROC
12.
J Youth Adolesc ; 44(4): 922-39, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25687264

RESUMEN

Better understanding risk factors for the development of adolescent emotional and behavioral problems can help with intervention and prevention efforts. Previous studies have found that an early menarcheal age predicts several adolescent problems, including depressive symptoms, delinquency, and early age at first intercourse. Few studies, nevertheless, have explicitly tested (a) whether the associations with menarcheal age vary across racial/ethnic groups or (b) whether the sources of the associations are within-families (i.e., consistent with a direct, causal link) or only between-families (i.e., due to selection or confounding factors). The current study analyzed data from a nationally representative US Sample of females (N = 5,637). We examined whether race/ethnicity moderated the associations between early menarche and several adolescent problems by using multiple-group analyses and we examined the degree to which genetic and environmental factors shared by family members account for the associations by comparing sisters and cousins with differing menarcheal ages. Menarcheal age predicted subsequent depressive symptoms, delinquency, and early age at first intercourse in the population. The magnitudes of the associations were similar across all racial/ethnic groups for all outcomes. The within-family associations (i.e., when comparing siblings and cousins with different menarcheal age) were large and statistically significant when predicting early intercourse, but not the other outcomes. The findings suggest that selection or confounding factors account for the associations between menarcheal age and subsequent depressive symptoms and delinquency, whereas the independent association between menarcheal age and early age at first intercourse is consistent with a direct, causal effect.


Asunto(s)
Conducta del Adolescente/psicología , Menarquia/fisiología , Trastornos del Humor/psicología , Adolescente , Adulto , Factores de Edad , Trastorno Depresivo/psicología , Femenino , Humanos , Adulto Joven
14.
Multivariate Behav Res ; 43(4): 654-5, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-26771431

RESUMEN

Individuals performing an experimental cognitive task have a choice whether to favor accuracy, speed, or weight them both equally. Models of speed/ accuracy tradeoff have been proposed in the assessment literature ( van der Linden, 2007 ) and experimental literature ( Ratcliff & Rouder, 1998 ). However, these models do not estimate individual differences in choice of speed/ accuracy tradeoff at between- and within-subjects levels. The top of Figure 1 presents the equations and path diagram for the SATin model. Individual differences in speed/ accuracy tradeoff will be modeled at two levels with, 1) variability in Tradeoff (between-subject level, Level 2) and 2) variability in c (within-subject level, Level 1). An individual's Tradeoff factor score represents the individual's distributional position relative to others regarding whether they favor speed (values < 0), accuracy (values > 0), or neither (value = 0). A negative c indicates that the individual is trading off speed and accuracy for these particular trials, whereas a positive and zero c indicate the individual is not trading off. [Figure: see text] Panels 1 and 2 illustrate Simpson's paradox, where speed/ accuracy tradeoff occurs in opposing directions at between- and within-subject levels. This highlights the need for a multi-level model as the researcher would draw opposing conclusions by observing only one of these levels. Simulations studies compared the SATin model to a popular model in cognitive psychology that uses speed alone to estimate ability. SATin outperformed this model by accounting for substantially more variance in actual ability.

15.
Appl Opt ; 42(3): 505-10, 2003 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-12570273

RESUMEN

Many observers have reported observations of green light emanating from severe thunderstorms in the midwestern United States. Spectral measurements have demonstrated that the dominant wavelength of the light is in the green portion of the visible spectrum and that this is not just a subjective impression. According to the theory proposed by Bohren and Fraser [Bull. Am. Meteorol. Soc. 74, 2185 (1993)], two effects combine to produce green light from thunderstorms. First, incident solar radiation is reddened by selective scattering by air molecules and particles in the atmosphere before it enters the cloud. Second, the radiation that passes through an optically thick cloud is attenuated in the longer wavelengths because of selective absorption by liquid water. Model calculations indicate that realizable combinations of mean drop diameters, mean liquid-water contents, and cloud thicknesses can satisfy the conditions required for shifting the dominant wavelength of the incident solar radiation to green.

16.
Appl Opt ; 41(33): 6931-6, 2002 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-12463236

RESUMEN

Observations of the spectrum of light from thunderstorms indicate that the radiance amplitude of the near-IR portion of the spectrum is often relatively greater in comparison with the amplitude of the radiance of the visible portion of the spectrum than it is in the spectrum of solar radiation at the surface. Observational data suggest that two mechanisms may cause this effect. The first is the reduction in the shorter wavelengths due to selective scattering, and the second is selective reflection from foliage.

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