Weak Alfvénic turbulence in a periodic domain is considered as a mixed state of Alfvén waves interacting with the two-dimensional (2D) condensate. Unlike in standard treatments, no spectral continuity between the two is assumed, and, indeed, none is found. If the 2D modes are not directly forced, k(-2) and k(-1) spectra are found for the Alfvén waves and the 2D modes, respectively, with the latter less energetic than the former. The wave number at which their energies become comparable marks the transition to strong turbulence. For imbalanced energy injection, the spectra are similar, and the Elsasser ratio scales as the ratio of the energy fluxes in the counterpropagating Alfvén waves. If the 2D modes are forced, a 2D inverse cascade dominates the dynamics at the largest scales, but at small enough scales, the same weak and then strong regimes as described above are achieved.
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http://dx.doi.org/10.1103/PhysRevE.85.036406 | DOI Listing |
Hum Reprod
January 2025
Department of Epidemiology, Brown University School of Public Health, Providence, RI, USA.
Study Question: Are empirically derived adolescent overweight/obesity phenotypes differentially associated with polycystic ovary syndrome (PCOS) in young adulthood?
Summary Answer: Self-reported PCOS diagnosis risk in young adulthood varied by empirically derived adolescent overweight/obesity phenotypes, with the highest risk observed among those in the 'mothers with obesity' and 'early puberty' phenotypes.
What Is Known Already: Overweight and obesity during puberty are postulated to promote the development of PCOS. Much of the prior literature in this area is cross-sectional and defines weight status based solely on BMI, yet emerging research suggests that not all people with overweight/obesity have the same risk for chronic health conditions, including PCOS.
J Urban Health
January 2025
Instituto de Medicina Social, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil.
Neighborhoods or residential environments have physical and social attributes which may contribute to inequalities in the overweight and obesity pandemic. We examined the longitudinal associations of baseline neighborhood-level income and racial residential segregation (using the Gi* statistic: low, medium, high) with changes in body mass index (BMI in kg/m), using geocoded data from 1821 civil servants in the municipality of Rio de Janeiro, Brazil, followed-up for approximately 13 years (baseline wave 1: 1999, wave 2: 2001-2002, wave 3: 2006-2007, wave 4: 2012-2013). Linear mixed effects models using BMI measured in all four study waves were performed, accounting for gender, race, length of residence, education and time-dependent age, and per capita family income.
View Article and Find Full Text PDFPlanta
January 2025
Normandie Université, UNICAEN, INRAE, UMR 950 Ecophysiologie Végétale, Agronomie Et Nutritions N, C, S, Esplanade de La Paix CS14032, 14032, Caen Cedex 5, France.
The effects of intense heat during the reproductive phase of two Brassica species-B. napus and C. sativa-could be alleviated by a prior gradual increase exposure and/or PGPR inoculation.
View Article and Find Full Text PDFPhys Eng Sci Med
January 2025
RF Longevity, 428 E. Thunderbird Road, Phoenix, SE, AZ, 85022, USA.
We have previously shown in small studies that full brain Transcranial Radiofrequency Wave Treatment (TRFT) to subjects with Alzheimer's Disease could stop and reverse their cognitive decline. An 8-emitter head device, the "MemorEM", was used in these studies to provide TRFT at 915 MHz frequency and power level of 1.6 W/kg Specific Absorption Rate (SAR) during daily 1-hour treatments.
View Article and Find Full Text PDFJ Acoust Soc Am
January 2025
Escola Politécnica, University of São Paulo, São Paulo, 05508-030, Brazil.
Ultrasonic sensors based on backscattering principles have been developed for various applications involving arbitrary or random scatterer distributions. Although the theory of multiple scattering of waves is well-established, it has not been thoroughly explored in these applications. This work presents a feasible and simplified three-dimensional scattering model to predict the transient response generated by a set of rods positioned in the near field of a 1 MHz water-coupled ultrasonic transducer.
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