Energetic alpha transport in a magnetized fusion target

Magnetized target fusion (MTF) promises to ease the power and intensity requirements for a fusion driver. High gain MTF targets require fusion ignition to occur in the magnetized fuel. Ignition requires the energy deposited by the charged fusion reaction products to exceed that lost from the plasma by a variety of loss mechanisms. The authors have used single particle tracking through a magnetized plasma to obtain preliminary results on the DT alpha particle deposition as a function of the plasma {rho}R and BR for a uniform spherically symmetric volume with a uniform B{sub {theta}} magnetic field. More complicated plasma density, temperature, and field distributions can be handled by the code, including 2-D distributions, but the efficiency of this approach makes extensive calculations impractical. A more efficient approach is needed, particularly for use in dynamic calculations. However, particle tracking is useful for obtaining information for building more accurate models of the deposition for use in survey codes

Modifiable and non-modifiable risk factors for preterm delivery among adolescent and young adult cancer survivors

Purpose: A cancer diagnosis in adolescence and young adulthood (AYA, ages 15–39) may affect future pregnancy outcomes. Previous studies have reported an increased risk of preterm delivery (< 37 weeks of gestation) after maternal cancer treatment. In this analysis, we evaluated whether non-cancer characteristics modify the association between an AYA cancer history and preterm birth. Methods: North Carolina Central Cancer Registry records (2000–2013) were linked to state birth certificate files (2000–2014) to identify births to AYA cancer survivors (n = 1,980). A comparison cohort of births to women without a cancer diagnosis was selected from birth certificate files (n = 11,860). Log-binomial regression was used to estimate risk ratios (RR) and 95% confidence intervals (CI) for preterm delivery. Effect modification by early prenatal care (1st trimester; yes/no), race/ethnicity (white/black/other), previous live births (0/1+), maternal age (< 25/25–29/30–34/35+), smoking during pregnancy (any/none), and education (high school or less/some college/Bachelor’s degree or higher) was evaluated using likelihood ratio tests (LRT). Results: Overall, preterm births were more common among AYA survivors than the comparison group (RR = 1.24, CI 1.07–1.43). The association was stronger among those who did not receive early prenatal care (RR = 1.73, CI 1.26–2.37) than among those who did (RR = 1.15, CI 0.98–1.35; LRT p = 0.03). Maternal age < 25 was also associated with a greater increase in preterm birth (< 25: RR = 1.80, CI 1.27–2.54; LRT p = 0.07). Associations did not vary strongly by other factors evaluated. Conclusions: An AYA cancer diagnosis may be associated with an increased risk of preterm birth, particularly among women who are younger and receive late or no prenatal care

Circle talks as situated experiential learning: Context, identity, and knowledgeability in \u27learning from reflection\u27

This article presents research that used ethnographic and sociolinguistic methods to study ways participants learn through reflection when carried out as a “circle talk.” The data indicate that participants in the event (a) invoked different contextual frames that (b) implicated them in various identity positions, which (c) affected how they could express their knowledge. These features worked together to generate socially shared meanings that enabled participants to jointly achieve conceptualization—the ideational role “reflection” is presumed to play in the experiential learning process. The analysis supports the claim that participants generate new knowledge in reflection, but challenges individualistic and cognitive assumptions regarding how this occurs. The article builds on situated views of experiential learning by showing how knowledge can be understood as socially shared and how learning and identity formation are mutually entailing processes

Uranium and Radon in Private Bedrock Well Water in Maine: Geospatial Analysis at Two Scales

In greater Augusta of central Maine, 53 out of 1093 (4.8%) private bedrock well water samples from 1534 km² contained [U] > 30 μg/L, the U.S. Environmental Protection Agency’s (EPA) Maximum Contaminant Level (MCL) for drinking water; and 226 out of 786 (29%) samples from 1135 km² showed [Rn] > 4,000 pCi/L (148 Bq/L), the U.S. EPA’s Alternative MCL. Groundwater pH, calcite dissolution and redox condition are factors controlling the distribution of groundwater U but not Rn due to their divergent chemical and hydrological properties. Groundwater U is associated with incompatible elements (S, As, Mo, F, and Cs) in water samples within granitic intrusions. Elevated [U] and [Rn] are located within 5–10 km distance of granitic intrusions but do not show correlations with metamorphism at intermediate scales (10⁰−10¹ km). This spatial association is confirmed by a high-density sampling (n = 331, 5–40 samples per km²) at local scales (≤10–1 km) and the statewide sampling (n = 5857, 1 sample per 16 km²) at regional scales (10²–103 km). Wells located within 5 km of granitic intrusions are at risk of containing high levels of [U] and [Rn]. Approximately 48 800–63 900 and 324 000 people in Maine are estimated at risk of exposure to U (> 30 μg/L) and Rn (> 4000 pCi/L) in well water, respectively

Frailty and Comorbidities among Survivors of Adolescent and Young Adult Cancer: A Cross-Sectional Examination of a Hospital-Based Survivorship Cohort

Purpose: Cancer survivors are at increased risk for the early development of age-related chronic medical conditions compared with peers without a history of cancer; however, little is known regarding the burden of these conditions among survivors of adolescent and young adult (AYA) cancers. In response, we sought to determine the prevalence of specific comorbidities and frailty among AYAs (15-39 years old at diagnosis) enrolled in a cancer survivorship cohort. Methods: Using a cross-sectional survey of a tertiary medical center-based cancer survivorship cohort, we determined the prevalence of specific comorbidities and frailty using the survey-based FRAIL assessment. In separate models adjusting for age, we estimated prevalence ratios (PRs) for the associations between patient characteristics and (1) any comorbidity and (2) frailty or prefrailty using log-binomial models. Results: We identified 271 AYA cancer survivors, most of whom were 30-39 years old at survey (57%). A majority of survivors (n = 163, 60%) reported having at least one comorbidity with the most common being depression (28%), anxiety (27%), asthma (17%), high cholesterol (15%), and hypertension (15%). Of the 184 AYA survivors at least 1 year from cancer diagnosis, 19 (10%) were classified as frail and 39 (21%) as prefrail. Survivors who were smokers (PR 2.0, 95% confidence interval [CI]: 1.16-3.56); obese (PR 1.7, 95% CI: 1.10-2.55); uninsured (PR 2.7, 95% CI: 1.63-4.59); or who reported comorbid depression or anxiety (PR 2.4, 95% CI: 1.51-3.67) were more likely to be frail or prefrail. Conclusions: The prevalence of frailty and comorbidities is high among AYA cancer survivors suggestive of accelerated aging

Patient/Provider Discussions about Clinical Trial Participation and Reasons for Nonparticipation among Adolescent and Young Adult Women with Cancer

Purpose: Clinical trial enrollment is low among adolescents and young adults (AYAs) with cancer and may contribute to inferior survival gains in recent years in this population compared with other age groups. We investigated clinical trial participation among AYA women with cancer, and examined whether patients discussed clinical trial participation with their doctor and reasons for nonparticipation. Methods: Women with a diagnosis of breast cancer, thyroid cancer, melanoma, lymphoma, or gynecologic cancer at ages 15-39 years during 2004-2016 were identified from the North Carolina Central Cancer Registry and the Kaiser Permanente Southern California health system. During 2018-2019, a total of 1264 eligible women completed an online survey (response = 13%), which examined survivorship issues among AYAs. Results: Overall, 5% of participants reported that they had participated in a clinical trial. Most women reported that they had not discussed clinical trial participation with a medical provider (76%) and that they did not know whether a relevant trial was available for their cancer (73%). Among those who knew that a trial was available but did not participate, the most commonly reported reasons for nonparticipation included concerns about side effects of the treatment in the trial and concerns that the treatment had not been sufficiently tested. Conclusion: Only a small proportion of AYA women with cancer in our cohort reported discussing a clinical trial with a provider or knowing whether a relevant trial was available. Our findings point to opportunities to improve patient/provider communication to increase clinical trial enrollment among AYAs with cancer

Niche as a determinant of word fate in online groups

Patterns of word use both reflect and influence a myriad of human activities and interactions. Like other entities that are reproduced and evolve, words rise or decline depending upon a complex interplay between {their intrinsic properties and the environments in which they function}. Using Internet discussion communities as model systems, we define the concept of a word niche as the relationship between the word and the characteristic features of the environments in which it is used. We develop a method to quantify two important aspects of the size of the word niche: the range of individuals using the word and the range of topics it is used to discuss. Controlling for word frequency, we show that these aspects of the word niche are strong determinants of changes in word frequency. Previous studies have already indicated that word frequency itself is a correlate of word success at historical time scales. Our analysis of changes in word frequencies over time reveals that the relative sizes of word niches are far more important than word frequencies in the dynamics of the entire vocabulary at shorter time scales, as the language adapts to new concepts and social groupings. We also distinguish endogenous versus exogenous factors as additional contributors to the fates of words, and demonstrate the force of this distinction in the rise of novel words. Our results indicate that short-term nonstationarity in word statistics is strongly driven by individual proclivities, including inclinations to provide novel information and to project a distinctive social identity.Comment: Supporting Information is available here: http://www.plosone.org/article/fetchSingleRepresentation.action?uri=info:doi/10.1371/journal.pone.0019009.s00

Time to cancer treatment and reproductive outcomes after fertility preservation among adolescent and young adult women with cancer

Background: Fertility preservation (FP) may be underused after cancer diagnosis because of uncertainty around delays to cancer treatment and subsequent reproductive success. Methods: Women aged 15 to 39 years diagnosed with cancer between 2004 and 2015 were identified from the North Carolina Central Cancer Registry. Use of assisted reproductive technology (ART) after cancer diagnosis between 2004 and 2018 (including FP) was assessed through linkage to the Society for Assisted Reproductive Technology. Linear regression was used to examine time to cancer treatment among women who did (n = 95) or did not (n = 469) use FP. Modified Poisson regression was used to estimate risk ratios (RRs) and 95% CIs for pregnancy and birth based on timing of ART initiation relative to cancer treatment (n = 18 initiated before treatment for FP vs n = 26 initiated after treatment without FP). Results: The median time to cancer treatment was 9 to 33 days longer among women who used FP compared with women who did not, matched on clinical factors. Women who initiated ART before cancer treatment may be more likely to have a live birth given pregnancy compared with women who initiated ART after cancer treatment (age-adjusted RR, 1.47; 95% CI, 0.98-2.23), though this may be affected by the more frequent use of gestational carriers in the former group (47% vs 20% of transfer cycles, respectively). Conclusions: FP delayed gonadotoxic cancer treatment by up to 4.5 weeks, a delay that would not be expected to alter prognosis for many women. Further study of the use of gestational carriers in cancer populations is warranted to better understand its effect on reproductive outcomes

You Know What It Is: Learning Words through Listening to Hip-Hop

Music listeners have difficulty correctly understanding and remembering song lyrics. However, results from the present study support the hypothesis that young adults can learn African-American English (AAE) vocabulary from listening to hip-hop music. Non-African-American participants first gave free-response definitions to AAE vocabulary items, after which they answered demographic questions as well as questions addressing their social networks, their musical preferences, and their knowledge of popular culture. Results from the survey show a positive association between the number of hip-hop artists listened to and AAE comprehension vocabulary scores. Additionally, participants were more likely to know an AAE vocabulary item if the hip-hop artists they listen to use the word in their song lyrics. Together, these results suggest that young adults can acquire vocabulary through exposure to hip-hop music, a finding relevant for research on vocabulary acquisition, the construction of adolescent and adult identities, and the adoption of lexical innovations