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We conducted a detailed investigation of U isotopes in conjunction with a broad geochemical investigation during field-scale biostimulation and desorption experiments. This investigation was carried out in the uranium-contaminated alluvial aquifer of the Rifle field research site. In this well-characterized setting, a more comprehensive understanding of U isotope geochemistry is possible. Our results indicate that U isotope fractionation is consistently observed across multiple experiments at the Rifle site. Microbially-mediated reduction is suggested to account for most or all of the observed fractionation as abiotic reduction has been demonstrated to impart much smaller, often near-zero, isotopic fractionation or isotopic fractionation in the opposite direction. Data from some time intervals are consistent with a simple model for transport and U(VI) reduction, where the fractionation factor (ε = +0.65‰ to +0.85‰) is consistent with experimental studies. However, during other time intervals the observed patterns in our data indicate the importance of other processes in governing U concentrations and 238U/235U ratios. For instance, we demonstrate that departures from Rayleigh behavior in groundwater systems arise from the presence of adsorbed species. We also show that isotope data are sensitive to the onset of oxidation after biostimulation ends, even in the case where reduction continues to remove contaminant uranium downstream. Our study and the described conceptual model support the use of 238U/235U ratios as a tool for evaluating the efficacy of biostimulation and potentially other remedial strategies employed at Rifle and other uranium-contaminated sites.

Optical measurements of the cervical transformation zone (sometimes referred to as the transition zone) using elastic-scattering spectroscopy, demonstrate sensitivity to the epithelial cell-type differences. ©2004 Copyright SPIE - The International Society for Optical Engineering.

The incidence of primary cutaneous melanoma has been increasing dramatically for several decades. Melanoma accounts for the majority of skin cancer-related deaths, but treatment is nearly always curative with early detection of disease. In this update of the guidelines of care, we will discuss the treatment of patients with primary cutaneous melanoma. We will discuss biopsy techniques of a lesion clinically suspicious for melanoma and offer recommendations for the histopathologic interpretation of cutaneous melanoma. We will offer recommendations for the use of laboratory and imaging tests in the initial workup of patients with newly diagnosed melanoma and for follow-up of asymptomatic patients. With regard to treatment of primary cutaneous melanoma, we will provide recommendations for surgical margins and briefly discuss nonsurgical treatments. Finally, we will discuss the value and limitations of sentinel lymph node biopsy and offer recommendations for its use in patients with primary cutaneous melanoma. [ABSTRACT FROM AUTHOR]

Purpose: To compare the diabetes self-management activities of African American primary caregiving grandmothers before and after the initiation of caregiving and to compare the diabetes self-management activities of African American primary caregiving grandmothers to diabetic women who were not caring for their grandchildren. Design: Using a cross-sectional, descriptive design, 68 African American women 55 to 75 years of age were recruited as part of a larger study examining the impact of caregiving responsibilities on the diabetic health of African American primary caregiving grandmothers. Each participant was asked the frequency of their performance of six self-management activities. Caregiving grandmothers were asked about these activities before and after the initiation of caregiving. Results: Dependent and independent t-tests with Bonferroni correction were used to analyze the data. Statistically significant differences were noted in diet ( t=4.400, p=.000) and self-monitoring of blood glucose (SMBG; t=3.484, p=.001) before and after the initiation of caregiving. For the caregiver versus non-caregiver comparison, statistically significant differences were noted in SMBG ( t=−3.855, p=.000) and eye examinations ( t=−3.211, p=.001). Conclusions: The findings provide preliminary data to support further research examining the self-management activities of diabetic African American primary caregiving grandmothers. Diabetic African American primary caregiving grandmothers may have a decreased ability to integrate self-management activities into their daily patterns of living. Additional research is needed to determine what factors prevent this population from performing these tasks routinely. Clinical Relevance: African American primary caregiving grandmothers were found to have more difficulty performing some of their self-management activities, which may severely impact their overall diabetic health. [ABSTRACT FROM AUTHOR]

Objective. This study examines the relationship between receiving diabetes self-management education (DSME) and having higher levels of comprehensive diabetes clinical care, a summation of up to five clinical services recommended for individuals with type 2 diabetes and those who have had type I diabetes for >/= 5 years. Design. Analysis of data from a population-based, cross-sectional study. Methods. Data for this study were from the 2007 Florida Behavioral Risk Factor Surveillance System (BRFSS), a statewide, random, cross-sectional survey of adults. A dichotomous comprehensive diabetes clinical care variable was constructed based on responses to questions from the BRFSS diabetes module, and a logistic regression model was fitted. Adjusted odds ratios (ORs) are reported. Results. Among Florida adults with diabetes, 51.5% had received DSME. About 51.4% of adults with diabetes who received DSME had a high level of comprehensive care compared to 31.8% of those who did not receive DSME. The OR for having a high level of comprehensive care was statistically significantly higher among adults who received DSME (OR = 2.48) compared to their counterparts who did not receive DSME. Other significant covariates were having health insurance (OR = 3.65), having graduated from high school (OR = 1.55), having a college education (OR = 2.70), being 45-64 years of age (OR = 2.31), and being >/= 65 years of age (OR = 5.29). Conclusions. These data show that receiving DSME is positively associated with receiving higher levels of comprehensive diabetes clinical care. [ABSTRACT FROM AUTHOR]

In a case-control study with prevalence sampling, the authors explored the correlates for nocturia and their population-level impact. In 2003-2004, questionnaires were mailed to 6,000 subjects (aged 18-79 years) randomly identified from the Finnish Population Register (62.4% participated; 53.7% were female). Questionnaires contained items on medical conditions, medications, lifestyle, sociodemographic and reproductive factors, urinary symptoms, and snoring. Nocturia was defined as > or =2 voids/night. In age-adjusted analyses, factors associated with nocturia were entered into a multivariate model. Backward elimination was used to select variables for the final model, with adjustment for confounding. Although numerous correlates were identified, none affected > or =50% of nocturia cases of both sexes. The factors with the greatest impact at the population level were (urinary) urgency (attributable number/1,000 subjects (AN) = 24), benign prostatic hyperplasia (AN = 19), and snoring (AN = 16) for men and overweight and obesity (AN = 40), urgency (AN = 24), and snoring (AN = 17) for women. Moreover, correlates included prostate cancer and antidepressant use for men, coronary artery disease and diabetes for women, and restless legs syndrome and obesity for both sexes. Although several correlates were identified, none accounted for a substantial proportion of the population burden, highlighting the multifactorial etiology of nocturia. [ABSTRACT FROM AUTHOR]

Context: Many states are developing tobacco use prevention and reduction programs, and current data on tobacco use behaviors and how these change over time in response to program activities are needed for program design, implementation, and evaluation.Objectives: To assess changes in youth cigarette use and intentions following implementation of the Florida Pilot Program on Tobacco Control.Design, Setting, and Participants: Self-administered survey conducted prior to program implementation (1998), and 1 and 2 years (1999, 2000) later among a sample of Florida public middle school and high school students who were classified as never users, experimenters, current users, and former users of cigarettes based on survey responses.Main Outcome Measures: Changes in cigarette use status, intentions, and behaviors among students over a 2-year period.Results: Surveys were completed by 22,540, 20,978, and 23, 745 students attending 255, 242, and 243 Florida public middle and high schools in 1998, 1999 and 2000, respectively. Response rates for the 3 survey years ranged from 80% to 82% and 72% to 82% for the middle school and high school surveys, respectively. After 2 years, current cigarette use dropped from 18.5% to 11.1% (P<.001) among middle school students and from 27.4% to 22.6% (P =.01) among high school students. Prevalence of never use increased from 56.4% to 69. 3% (P<.001) and from 31.9% to 43.1% (P =.001) among middle school and high school students, respectively. Prevalence of experimenting decreased among middle school and high school students from 21.4% to 16.2% (P<.001) and from 32.8% to 28.2% (P<.001), respectively. Among never users, the percentage of committed nonsmokers increased from 67.4% to 76.9% (P<.001) and from 73.7% to 79.3% (P<.001) among middle school and high school students, respectively. Among experimenters, the percentage of students who said they will not smoke again increased from 30.4% to 42.0% (P<.001) in middle school and from 44.4% to 51.0% (P<.001) in high school.Conclusions: Progress toward reduction of youth tobacco use was observed in each of the 2 years of Florida's Pilot Program on Tobacco Control. Our results suggest that a comprehensive statewide program can be effective in preventing and reducing youth tobacco use. JAMA. 2000;284:723-728 [ABSTRACT FROM AUTHOR]

Some patients' beliefs about the causes and cures of illness are at odds with your Western biomedical training. To treat them successfully, you need to understand their health perceptions, behaviors, and expectations. [ABSTRACT FROM AUTHOR]

Arterial dissections are life-threatening occurrences. Ultrasound is useful in identifying the presence of a dissection and evaluating its extent. Presented is a case of an extensive arterial dissections extending from the carotid arteries through the iliac arteries. [ABSTRACT FROM AUTHOR]

Background: Nocturia (waking from sleep at night to void) and chronic insomnia frequently co-exist in older adults, contributing synergistically to sleep disturbance. Treatments typically target either nocturia or insomnia rather than simultaneously addressing shared mechanisms for these disorders., Methods: We conducted a multisite feasibility study to: (1) test and refine a protocol for recruitment, randomization, and assessment of older adults with co-existing nocturia and insomnia; and (2) examine preliminary changes in outcome measures to inform a future larger, multisite clinical trial. Participants were men and women aged 60 years and older recruited from outpatient clinics, reporting an average of two or more nocturia episodes per night over the past 4 weeks and meeting diagnostic criteria for chronic insomnia disorder. Participants were randomized to receive either integrated cognitive-behavioral therapy for insomnia and nocturia or a health education control program involving five weekly visits with a trained nurse practitioner interventionist. Outcomes (e.g., nocturia episodes) were measured 1-week post-treatment and 4-month post-randomization. Descriptive statistics examined the feasibility of outcomes to guide preparations for a future efficacy trial., Results: Of 245 adults screened, 55% were ineligible and 25% declined to participate. Sixty-one percent of 49 participants who provided informed consent were randomized. Of the 30 participants randomized (mean age = 70.6 years, 60% White), 14 were assigned to integrated cognitive-behavioral treatment and 16 to the control group. All randomized participants provided 4-month follow-up data. At 4 months, mean nightly nocturia episodes decreased by 0.9 (SD 1.0) in the integrated treatment group and by 0.2 (SD 1.2) in the control group compared with baseline., Discussion: Findings demonstrate the feasibility of recruiting, randomizing, and collecting outcome data from older adults (predominantly male) assigned to an integrated cognitive-behavioral therapy for coexisting insomnia and nocturia or a health education control program., (© 2024 The Author(s). Journal of the American Geriatrics Society published by Wiley Periodicals LLC on behalf of The American Geriatrics Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

CR-39 proton radiography is an experimental charged-particle backlighter platform fielded and used at OMEGA and the NIF to image electric and magnetic fields in a subject plasma. Processing a piece of CR-39 involves etching it in hot NaOH, and the etch time can greatly impact the background-to-signal ratio (BSR) in low-fluence (≲4 × 104 cm-2) regions and detection efficiency in high-fluence regions (≳7 × 105 cm-2). For CR-39 data with high fluence variation, these effects mean that any single etch time will result in ≳15% error in the measured signal in either the high- or low-fluence regions. This study aims to quantify the impact of the etch time on the BSR and efficiency losses and how these affect the field reconstruction. Experiments at the MIT Linear Electrostatic Ion Accelerator provided empirical values of the BSR and efficiency losses as a function of the fluence and etch time for fluences ranging from 3 × 103 to 7 × 105 cm-2. Synthetic radiographs were generated with known fields and modulated based on empirical values of BSR and efficiency losses. The fields were reconstructed using a Monge-Ampère code with the modulated radiographs as input. The results indicate that combining short and long etches allows for more accurate analysis of radiographs with high fluence variation, with the mean squared error of the reconstructed fields decreasing by factors of 1.2-7 compared to the reconstructions using only one etch time., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).)

Measurement of proton spectra is an important diagnostic for a variety of high energy density physics experiments. Current diagnostics are either not designed to capture the spectrum of low-energy protons or are unsuitable for high debris experiments. To bridge the gap, a new CR-39 based compact magnetic spectrometer (MagSpec) has been developed to measure proton spectra in the 1-20 MeV energy range, with a particular focus on the low-energy (1-6 MeV) spectrum, for use in experiments at the OMEGA Laser Facility and the National Ignition Facility (NIF). In the MagSpec diagnostic, protons of different energies are dispersed as they pass through a magnetic field before impinging on a differentially filtered CR-39 surface, resulting in a spatial distribution of CR-39 tracks that corresponds to the energy spectrum. In this paper, we discuss details of the design and implementation of MagSpec on the NIF and OMEGA., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).)

This paper reports on investigations on the impact of higher neutron fluences on the detection efficiency of protons with CR-39, a charged particle track detector. CR-39 is widely used as a diagnostic for inertial fusion applications and is an integral component of numerous particle diagnostics at the OMEGA laser facility and National Ignition Facility. As experiments continue to produce higher and higher yields, existing diagnostics are impacted by higher particle fluences than they were originally designed for. This paper presents data from experiments measuring proton signal on pieces of CR-39 with different levels of neutron fluence with two different etch times. The experiments show a decrease in signal recovery with increased neutron fluence, which is exacerbated at longer etch times. At 3 h etch time, data suggest a 17% ± 7% signal loss at 1.3 × 105 neutron-induced tracks per cm2 and a 67% ± 21% loss at 6 h etch time. Careful signal isolation techniques can recover most of the proton tracks even with moderate neutron fluence., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC) license (https://creativecommons.org/licenses/by-nc/4.0/).)

Image plates (IPs), or phosphor storage screens, are a technology employed frequently in inertial confinement fusion (ICF) and high energy density plasma (HEDP) diagnostics because of their sensitivity to many types of radiation, including, x rays, protons, alphas, beta particles, and neutrons. Prior studies characterizing IPs are predicated on the signal level remaining below the scanner saturation threshold. Since the scanning process removes some signal from the IP via photostimulated luminescence, repeatedly scanning an IP can bring the signal level below the scanner saturation threshold. This process, in turn, raises concerns about the signal response of IPs after an arbitrary number of scans and whether such a process yields, for example, a constant ratio of signal between the nth and n + 1st scan. Here, the sensitivity of IPs is investigated when scanned multiple times. It is demonstrated that the ratio of signal decay is not a constant with the number of scans and that the signal decay depends on the x-ray energy. As such, repeatedly scanning an IP with a mixture of signal types (e.g., x ray, neutron, and protons) enables ICF and HEDP diagnostics employing IPs to better isolate a particular signal type., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).)

Image plates (IPs) are a quickly recoverable and reusable radiation detector often used to measure proton and x-ray fluence in laser-driven experiments. Recently, IPs have been used in a proton radiography detector stack on the OMEGA laser, a diagnostic historically implemented with CR-39, or radiochromic film. The IPs used in this and other diagnostics detect charged particles, neutrons, and x-rays indiscriminately. IPs detect radiation using a photo-stimulated luminescence (PSL) material, often phosphor, in which electrons are excited to metastable states by ionizing radiation. Protons at MeV energies deposit energy deeper into the IP compared with x rays below ∼20 keV due to the Bragg peak present for protons. This property is exploited to discriminate between radiation types. Doses of mono-energetic protons between 1.7 and 14 MeV are applied to IPs using the MIT linear electrostatic ion accelerator. This paper presents the results from consecutive scans of IPs irradiated with different proton energies. The PSL ratios between subsequent scans are shown to depend on proton energy, with higher energy protons having lower PSL ratios for each scan. This finding is separate from the known energy dependence in the absolute sensitivity of IPs. The results can be compared to complimentary work on x rays, showing a difference between protons and x rays, forging a path to discriminate between proton and x-ray fluence in mixed radiation environments., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).)

Radiochromic film (RCF) and image plates (IPs) are both commonly used detectors in diagnostics fielded at inertial confinement fusion (ICF) and high-energy-density physics (HEDP) research facilities. Due to the intense x-ray background in all ICF/HEDP experiments, accurately calibrating the optical density of RCF as a function of x-ray dose, and the photostimulated luminescence per photon of IPs as a function of x-ray energy, is necessary for interpreting experimental results. Various measurements of the sensitivity curve of different IPs to x rays have been performed [Izumi et al., Proc. SPIE 8850, 885006 (2013) and Rosenberg et al., Rev. Sci. Instrum. 90(1), 013506 (2019)]; however, calibrating RCF is a tedious process that depends on factors such as the orientation in which the RCF is scanned in the film scanner and the batch of RCF used. These issues can be mitigated by cross-calibrating RCF with IPs to enable the use of IPs for the determination of dose on the RCF without scanning the RCF. Here, the first cross-calibration of RCF with IPs to quasi-monoenergetic titanium, copper, and molybdenum K-line x rays is presented. It is found that the IP-inferred dose rates on the RCF for the Ti and Mo x rays agree well with the measured dose rates, while the IP-inferred dose rate for the Cu x rays is larger than the measured dose rate by ∼2×. Explanations for this discrepancy and plans for future work are discussed., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).)

Objectives: Current evidence describing physical activity (PA) and sedentary time (ST) in people with and without heart failure (HF) is limited. This study examines PA participation and ST in a nationally representative sample of US adults with and without self-reported HF., Methods: The study sample (N = 21,633) included US adult (40 years old and older) participants from the 2007-2018 National Health and Nutrition Examination Survey. PA participation, ST, and HF status were assessed via a questionnaire., Results: Compared with participants without HF (68%), 84% of participants with HF reported not meeting PA recommendations ( P < 0.05). Compared with participants without HF (63%), 75% of participants with HF reported >4.5 hours/day of ST ( P < 0.05). Unadjusted analysis suggests that participants with HF had 60% ( P < 0.05) lower odds of reporting meeting PA recommendations when compared with those without HF. In a fully adjusted model, these odds were attenuated (odds ratio 0.74, P < 0.05). Similarly, unadjusted analysis illustrated those individuals with HF had 42% ( P < 0.05) lower odds of reporting ≤4.5 hours/day of ST. In a fully adjusted model, these odds also were attenuated (odds ratio 0.66, P < 0.05)., Conclusions: Our findings suggest that US adults with HF report significantly less PA and greater amounts of ST than those without HF.

Antiretroviral therapy has dramatically increased the lifespan of people living with HIV (PLWH), but advance care planning (ACP) and hospice services are underutilized in this population. The purpose of this study was to understand barriers and facilitators to ACP among this group. PLWH ( n = 25) were recruited from an HIV Clinic at a Veterans Affairs (VA) Medical Center in Atlanta, GA to represent a range of sociodemographic characteristics and experiences. Semi-structured interviews were analyzed using thematic analysis. More than half of participants (64%) indicated not engaging in ACP. We identified four key barriers to ACP: (1) a self-image among PLWH as "survivors" (and a reluctance to think about ACP); (2) a history of mistrust and mistreatment; (3) weak social ties and a desire to avoid disclosure of HIV status; and (4) a value for self-reliance. Findings have important implications for interventions to overcome these barriers., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: V.C. Marconi has received investigator-initiated research grants (to Emory University) and consultation fees from Eli Lilly, Bayer, Gilead Sciences, Merck, and ViiV. The other authors declare no conflicts of interest.