Tag: nevin manimala

Phys Rev Lett. 2024 Dec 31;133(26):266704. doi: 10.1103/PhysRevLett.133.266704.

ABSTRACT

The Landau-Lifshitz-Gilbert (LLG) and Landau-Lifshitz (LL) equations play an essential role for describing the dynamics of magnetization in solids. While a quantum analog of the LL dynamics has been proposed in [Phys. Rev. Lett. 110, 147201 (2013)PRLTAO0031-900710.1103/PhysRevLett.110.147201], the corresponding quantum version of LLG remains unknown. Here, we propose such a quantum LLG equation that inherently conserves purity of the quantum state. We examine the quantum LLG dynamics of a dimer consisting of two interacting spin-1/2 particles. Our analysis reveals that, in the case of ferromagnetic coupling, the evolution of initially uncorrelated spins mirrors the classical LLG dynamics. However, in the antiferromagnetic scenario, we observe pronounced deviations from classical behavior, underscoring the unique dynamics of becoming a spinless state, which is nonlocally correlated. Moreover, when considering spins that are initially entangled, our study uncovers an unusual form of revival-type quantum correlation dynamics, which differs significantly from what is typically seen in open quantum systems.

PMID:39879062 | DOI:10.1103/PhysRevLett.133.266704

Phys Rev Lett. 2024 Dec 31;133(26):267102. doi: 10.1103/PhysRevLett.133.267102.

ABSTRACT

We consider many-particle diffusion in one spatial dimension modeled as “random walks in a random environment.” A shared short-range space-time random environment determines the jump distributions that drive the motion of the particles. We determine universal power laws for the environment’s contribution to the variance of the extreme first passage time and extreme location. We show that the prefactors rely upon a single extreme diffusion coefficient that is equal to the ensemble variance of the local drift imposed on particles by the random environment. This coefficient should be contrasted with the Einstein diffusion coefficient, which determines the prefactor in the power law describing the variance of a single diffusing particle and is equal to the jump variance in the ensemble averaged random environment. Thus a measurement of the behavior of extremes in many-particle diffusion yields an otherwise difficult to measure statistical property of the fluctuations of the generally hidden environment in which that diffusion occurs. We verify our theory and the universal behavior numerically over many random walk in a random environment models and system sizes.

PMID:39879054 | DOI:10.1103/PhysRevLett.133.267102

Phys Rev Lett. 2024 Dec 31;133(26):261002. doi: 10.1103/PhysRevLett.133.261002.

ABSTRACT

Using tremendous photon statistics gained with the stray light aperture of the NuSTAR telescope over 11 years of operation, we set strong limits on the emission of close to monochromatic photons from the radiative decays of putative dark matter sterile neutrinos in the Milky Way. In the energy range of 3-20 keV covered by the NuSTAR, the obtained limits reach the bottom edge of theoretical predictions of realistic models where sterile neutrinos are produced in the early Universe. Only a small region is left to explore, if the sterile neutrinos form the entire dark matter component.

PMID:39879052 | DOI:10.1103/PhysRevLett.133.261002

Phys Rev Lett. 2024 Dec 31;133(26):261001. doi: 10.1103/PhysRevLett.133.261001.

ABSTRACT

Joint gravitational-wave and γ-ray burst (GRB) observations are among the best prospects for standard siren cosmology. However, the strong selection effect for the coincident GRB detection, which is possible only for sources with small inclination angles, induces a systematic uncertainty that is currently not accounted for. We show that this severe source of bias can be removed by inferring the a priori unknown electromagnetic detection probability directly from multimessenger data. This leads at the same time to an unbiased measurement of the Hubble constant, to constrain the properties of GRB emission, and to accurately measure the viewing angle of each source. Our inference scheme is applicable to real data already in the small-statistics regime, a scenario that might become reality in the near future. Additionally, we introduce a novel likelihood approximant for gravitational-wave events which treats the dependence on distance and inclination as exact.

PMID:39879018 | DOI:10.1103/PhysRevLett.133.261001

JAMA Netw Open. 2025 Jan 2;8(1):e2456238. doi: 10.1001/jamanetworkopen.2024.56238.

ABSTRACT

IMPORTANCE: Pediatric obesity and hypertension are highly correlated. To mitigate both conditions, provision of counseling on nutrition, lifestyle, and weight to children with high blood pressure (BP) measurements is recommended.

OBJECTIVE: To examine racial and ethnic disparities in receipt of nutrition, lifestyle, and weight counseling among patients with high BP at pediatric primary care visits stratified by patients’ weight status.

DESIGN, SETTING, AND PARTICIPANTS: This was a post hoc secondary analysis of the BP-CATCH study, a matched, stepped-wedge cluster randomized clinical trial investigating the best methods to screen children with high BP measurements and manage their care. Urban, suburban, and rural pediatric primary care practices across the US with a multidisciplinary team of at least 1 physician, 1 nurse and another practice associate, and a hypertension specialist for their practice group submitted baseline data from clinical encounters documented between November 2018 and January 2019. Practices identified the first 17 eligible patients with high BP measurements each month. This analysis was conducted from October 2023 to July 2024.

EXPOSURES: Race and ethnicity (Black, Hispanic, White, and other [Asian, multiracial, other races, and unknown race]) and weight status (with or without obesity).

MAIN OUTCOMES AND MEASURES: Primary outcomes were receipt of counseling on nutrition, lifestyle, and weight during primary care visits. Baseline measures extracted from medical records included demographics, anthropometric measures, and systolic and diastolic BP.

RESULTS: Of 2677 participants from 59 practices, 1516 (56.6%) were male; mean (SD) age was 10.8 (5.2) years. A total of 593 (21.1%) were Black; 414 (15.5%), Hispanic; 1111 (41.5%), White; and 559 (20.9%), other race and ethnicity. The overall crude unadjusted rates of receiving counseling were 63.5% (n = 1564 of 2463) for nutrition, 57.6% (n = 1419 of 2462) for lifestyle, 47.5% (n = 571 of 1202) for weight, and 46.4% (n = 1142 of 2461) for all counseling topics. Compared with the other 3 groups, Hispanic participants received significantly higher adjusted rates of nutrition (78.6%; 95% CI, 73.5%-83.8%), lifestyle (69.3%; 95% CI, 63.6%-74.9%), and all 3 (52.1%; 95% CI, 46.1%-58.2%) counseling topics. There were no significant differences in rates of receiving weight counseling between any pairs of groups. These findings were consistent in general among participants without obesity, and no significant pairwise differences were noted among participants with obesity except that nutrition counseling rates were significantly different between White participants and those reporting other race and ethnicity (68.3% [95% CI, 61.1%-75.4%] vs 81.6% [95% CI, 74.2%-89.1%]; Bonferroni-corrected P = .02).

CONCLUSIONS AND RELEVANCE: This secondary analysis of the BP-CATCH trial found that among children with high BP measurements, racial and ethnic disparities in receiving nutrition, lifestyle, and all 3 counseling topics were significant, although no significant disparities in receipt of weight counseling were noted. Racial disparities in receipt of counseling were not observed in participants with and without obesity.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03783650.

PMID:39878982 | DOI:10.1001/jamanetworkopen.2024.56238

JAMA Netw Open. 2025 Jan 2;8(1):e2456246. doi: 10.1001/jamanetworkopen.2024.56246.

ABSTRACT

IMPORTANCE: Multiple organ dysfunction (MOD) is a leading cause of in-hospital child mortality. For survivors, posthospitalization health care resource use and costs are unknown.

OBJECTIVE: To evaluate longitudinal health care resource use and costs after hospitalization with MOD in infants (aged <1 year) and children (aged 1-18 years).

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used nationwide data from 2004 to 2019 from Optum’s deidentified Clinformatics Data Mart Database, an insurance claims database. Infants and children from birth to age 18 years with an index hospitalization between January 1, 2005, and December 31, 2018, were included. Infants (age <1 year) and children (age 1-18 years) with MOD (MOD cohort) or without MOD (non-MOD cohort) were separately identified, and cohorts were propensity score weighted to balance demographics and pre-index hospitalization characteristics, including health care use and comorbidities. The data were analyzed between January 7, 2022, and September 8, 2023.

MAIN OUTCOMES AND MEASURES: Weighted generalized estimating equations were used to evaluate differences between cohorts in rehospitalizations, emergency department visits, and health care costs up to 5 years after the index hospitalization.

RESULTS: During the study period, 9671 children in the MOD cohort were compared with 1 691 793 children in the non-MOD cohort in the weighted sample. Infants comprised 67.4% of the MOD cohort (mean [SD] age at index hospitalization, 0.1 [0.8] years; 51.2% male) and 87% of the non-MOD cohort (mean [SD] age at index hospitalization, 0.1 [0.8] years; 50.8% male), and children comprised 32.5% of the MOD cohort (mean [SD] age at index hospitalization, 11.6 [5.7] years; 50.7% female) and 13.0% of the non-MOD cohort (mean [SD] age at index hospitalization, 11.5 [5.5] years; 51.3% female). The infant MOD cohort had more emergency department visits, with an adjusted incidence rate ratio of 1.76 (95% CI, 1.56-1.97) at 30 days; this difference persisted for years 1 through 5. Children had a similar pattern except at 30 days among those who acquired new organ-supportive technology during the index hospitalization. Among infants, the MOD cohort had more rehospitalizations, with an adjusted incidence rate ratio of 12.45 (95% CI, 11.40-13.59) at 30 days; this difference persisted for years 1 through 5. A similar pattern was observed among children. Annual health care costs were higher for the MOD cohort in year 1 (infants: mean [SD], $80 133 [$6543] vs $5183 [$19] [P < .001]; children: mean [SD], $54 113 [$17 544] vs $10 935 [$95] [P < .001]) and in all years through year 5.

CONCLUSIONS AND RELEVANCE: In this cohort study of nearly 1.7 million children, survivors of MOD accrued substantial ongoing health care resource use and cost burden after the index hospitalization. These findings suggest that follow-up care of survivors of MOD should include economic well-being alongside measures of clinical health.

PMID:39878981 | DOI:10.1001/jamanetworkopen.2024.56246

JAMA Netw Open. 2025 Jan 2;8(1):e2456264. doi: 10.1001/jamanetworkopen.2024.56264.

ABSTRACT

IMPORTANCE: Limited research explores mental health disparities between individuals in sexual and gender minority (SGM) populations and cisgender heterosexual (non-SGM) populations using national-level data.

OBJECTIVE: To explore mental health disparities between SGM and non-SGM populations across sexual orientation, sex assigned at birth, and gender identity within the All of Us Research Program.

DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study used survey data and linked electronic health records of eligible All of Us Research Program participants from May 31, 2017, to June 30, 2022.

EXPOSURE: Self-identified SGM status.

MAIN OUTCOMES AND MEASURES: Prevalence of common mental health conditions identified from linked electronic health records. Logistic regression adjusted for age, race and ethnicity, educational level, income, employment status, and geographic region was used to assess the association between SGM status and mental health conditions.

RESULTS: Among 413 457 participants, 269 947 (65.3%) were included in the analysis (median age, 59 [IQR, 43-70] years), with 22 189 (8.2%) self-identified as SGM. Men with cisgender sexual minority identity had higher odds of bipolar disorder (adjusted odds ratio [AOR], 1.87; 95% CI, 1.70-2.56) compared with cisgender heterosexual men. Women with cisgender sexual minority identity had higher odds of bipolar disorder (AOR, 2.09; 95% CI, 1.95-2.25) compared with cisgender heterosexual women. Gender diverse people assigned female sex at birth had higher odds of posttraumatic stress disorder (PTSD) compared with both cisgender heterosexual men (AOR, 3.67; 95% CI, 2.99-4.50) and cisgender heterosexual women (AOR, 2.77; 95% CI, 2.26-3.40). Gender diverse individuals assigned male sex at birth had higher odds of bipolar disorder (AOR, 2.35; 95% CI, 1.66-3.33) compared with cisgender heterosexual men and higher odds of attention-deficit/hyperactivity disorder (AOR, 2.19; 95% CI, 1.48-3.23) compared with cisgender heterosexual women. Transgender men had higher odds of depression (AOR, 2.11; 95% CI, 1.80-2.49) compared with cisgender heterosexual men, while transgender women had higher odds of any personality disorder (AOR, 2.71; 95% CI, 1.84-3.99) compared with cisgender heterosexual women.

CONCLUSIONS AND RELEVANCE: In this cross-sectional study of participants in the All of Us Research Program, there were significant mental health disparities between participants in SGM and non-SGM groups. These findings underscore the need for tailored mental health interventions to improve the well-being of SGM populations, while noting that the associations do not imply causality but reflect the stigma and minority stress experienced by these individuals.

PMID:39878980 | DOI:10.1001/jamanetworkopen.2024.56264

JAMA Netw Open. 2025 Jan 2;8(1):e2456528. doi: 10.1001/jamanetworkopen.2024.56528.

ABSTRACT

IMPORTANCE: There is a clear benefit to body armor against firearms; however, it remains unclear how these vests may influence day-to-day patient encounters when worn by emergency medical services (EMS).

OBJECTIVE: To determine the association of ballistic vests worn by EMS clinicians with workplace violence (WPV) and disparities in care among racial and/or ethnic minority patients.

DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of a volunteer-based sample of EMS clinicians at a large, multistate EMS agency encompassing 15 ground sites across the Midwest from April 1, 2023, to March 31, 2024. Data were analyzed from May to June 2024.

EXPOSURE: External ballistic armor being used by a group of self-selected clinicians on every run.

MAIN OUTCOMES AND MEASURES: Prevalence and characteristics associated with WPV and with declines of treatment and/or transport compared between crews with 1 or more vested vs no vested members.

RESULTS: A total of 156 of 415 staff (37.6%) opted in to wear the vests, including 77 male participants (49.4%). Prevalence of WPV was higher for vested crews (1.11 vs 0.85 cases per 100 runs; adjusted risk ratio [aRR], 1.28; 95% CI, 1.10 to 1.50; P = .001) and was due to higher rates of verbal abuse. The presence of 1 or more vested crew members increased the likelihood of all patients declining EMS treatment and/or transport; however, effect size was highest among patients with an unknown race and/or ethnicity (2234 [21.1%] vs 2134 [16.5%] patients; aRR, 1.19; 95% CI, 1.10 to 1.27; P < .001), followed by racial and/or ethnic minority patients (708 [16.7%] vs 399 [13.8%] patients; aRR, 1.18; 95% CI, 1.05 to 1.33; P = .01). Analyses of individual minority groups revealed a significant increase only in Black or African American patients declining treatment and/or transport by vested crews (461 [17.6%] vs 223 [13.7%] patients; RR, 1.28; 95% CI, 1.10 to 1.49; P = .002).

CONCLUSIONS AND RELEVANCE: In this cohort study, vested crews experienced increased prevalence of WPV compared with nonvested crews. Use of vests increased the frequency of all patients declining EMS treatment and/or transport. Among minority groups, there was a significant increase in Black or African American patients declining treatment and/or transport. Agencies should consider benefits and unintended consequences of EMS clinicians wearing body armor.

PMID:39878979 | DOI:10.1001/jamanetworkopen.2024.56528

J Vis Exp. 2025 Jan 10;(215). doi: 10.3791/67475.

ABSTRACT

Chronic wounds, due to their high prevalence, are a serious global health concern. Effective therapeutic strategies can significantly accelerate healing, thereby reducing the risk of complications and alleviating the economic burden on healthcare systems. Although numerous experimental studies have investigated wound healing, most rely on qualitative observations or quantitative direct measurements. The objective of this study was to standardize an indirect wound measurement method using digital planimetry, incorporating digital scaling and segmentation. This approach addresses the lack of detailed, step-by-step methodologies for accurate wound assessment. A photodocumentation booth was designed and constructed, and computer-assisted digital planimetry tools were employed to minimize variability in measurements of the wound area, perimeter, and the distance from the wound center to its edges. A circular traumatic wound (5 mm in diameter) was created on the dorsal midline at the shoulder blade level of male CD1 mice (n = 4, 10 weeks old, 30-35 g). Wound evolution was photodocumented for 14 days using the custom-designed photo booth, which controlled lighting conditions, focal distance, and subject positioning. Scaling and wound measurements were performed using segmentation in ImageJ software, and statistical analysis was conducted using statistical analysis software. The kinetics of wound closure showed a slight increase in wound size and perimeter between day 0 and day 2, followed by a gradual decrease until complete closure by day 14. The photodocumentation booth and computer-assisted digital planimetry enabled quantitative measurements with minimal variability. In conclusion, these tools provide a reliable and reproducible method for evaluating wound closure kinetics in pre-clinical models.

PMID:39878954 | DOI:10.3791/67475

JMIR Aging. 2025 Jan 29;8:e69493. doi: 10.2196/69493.

NO ABSTRACT

PMID:39878948 | DOI:10.2196/69493