Nevin Manimala

Phys Rev Lett. 2022 Aug 26;129(9):090602. doi: 10.1103/PhysRevLett.129.090602.

ABSTRACT

The transverse-field Ising model is one of the fundamental models in quantum many-body systems, yet a full understanding of its dynamics remains elusive in higher than one dimension. Here, we show for the first time the breakdown of ergodicity in d-dimensional Ising models with a weak transverse field in a prethermal regime. We demonstrate that novel Hilbert-space fragmentation occurs in the effective nonintegrable model with d≥2 as a consequence of only one emergent global conservation law of the domain wall number. Our results indicate nontrivial initial-state dependence for nonequilibrium dynamics of the Ising models with a weak transverse field.

PMID:36083664 | DOI:10.1103/PhysRevLett.129.090602

Phys Rev Lett. 2022 Aug 26;129(9):093604. doi: 10.1103/PhysRevLett.129.093604.

ABSTRACT

Quantum interference between identical single particles reveals the intrinsic quantum statistic nature of particles, which could not be interpreted through classical physics. Here, we demonstrate quantum interference between nonidentical bosons using a generalized beam splitter based on a quantum memory. The Hong-Ou-Mandel type interference between single photons and single magnons with high visibility is demonstrated, and the crossover from the bosonic to fermionic quantum statistics is observed by tuning the beam splitter to be non-Hermitian. Moreover, multiparticle interference that simulates the behavior of three fermions by three input photons is realized. Our work extends the understanding of the quantum interference effects and demonstrates a versatile experimental platform for studying and engineering quantum statistics of particles.

PMID:36083656 | DOI:10.1103/PhysRevLett.129.093604

Phys Rev Lett. 2022 Aug 26;129(9):094101. doi: 10.1103/PhysRevLett.129.094101.

ABSTRACT

Extreme value (EV) statistics of correlated systems are widely investigated in many fields, spanning the spectrum from weather forecasting to earthquake prediction. Does the unavoidable discrete sampling of a continuous correlated stochastic process change its EV distribution? We explore this question for correlated random variables modeled via Langevin dynamics for a particle in a potential field. For potentials growing at infinity faster than linearly and for long measurement times, we find that the EV distribution of the discretely sampled process diverges from that of the full continuous dataset and converges to that of independent and identically distributed random variables drawn from the process’s equilibrium measure. However, for processes with sublinear potentials, the long-time limit is the EV statistics of the continuously sampled data. We treat processes whose equilibrium measures belong to the three EV attractors: Gumbel, Fréchet, and Weibull. Our Letter shows that the EV statistics can be extremely sensitive to the sampling rate of the data.

PMID:36083641 | DOI:10.1103/PhysRevLett.129.094101

JMIR Form Res. 2022 Sep 9;6(9):e36432. doi: 10.2196/36432.

ABSTRACT

BACKGROUND: Young people are increasingly seeking out web-based support for their mental health and well-being. Peer support forums are popular with this age group, with young individuals valuing the fact that the forums are available 24/7, providing a safe and anonymous space for exploration. Currently, little systematic evaluation of the helpfulness of such forums in providing support has been conducted.

OBJECTIVE: This study examined the helpfulness of the support offered within web-based mental health and well-being peer support forums for young people. It specifically investigated the self-reported user ratings of helpfulness reported through the completion of a developing experience measure. The ratings will be used to consider further development of the measure and reflect upon the overall helpfulness of the forums as indicated by the reported scores.

METHODS: The study used routinely collected practice-based outcome data from web-based mental health forums for young people. These forums are hosted by the UK-based web-based therapy and support service, Kooth. A cross-sectional design was used to explore-using a range of inferential statistical measures-the outcomes reported by those accessing the forums using a Peer Online Community Experience Measure (POCEM). To consider the helpfulness in general, 23,443 POCEMs completed in 2020 were used. A second data set of 17,137 completed POCEMs from the same year was used to consider whether various engagement indicators had an impact upon the helpfulness rating.

RESULTS: Female users aged between 11 and 16 years predominantly completed the POCEM. This is in keeping with the majority of those using the service. In total, 74.6% (8240/11,045) of the scores on the POCEM indicated that the individuals found the posts helpful. An ANOVA indicated that male users were more likely to report obtaining intrapersonal support, whereas female users obtained interpersonal support. Furthermore, the POCEM scores reflected the internal consistency of the measure and provided an insight into the way that young people made use of the peer support resource; for instance, posts that were rated more helpful were correlated with spending longer time reading them, and the topics discussed varied throughout the day with more mental health issues being discussed later at night.

CONCLUSIONS: The results seem to demonstrate that, overall, the young people involved in this study found web-based peer support helpful. They indicate that peer support can provide an important strand of care within a supportive mental health ecosystem, particularly during time periods when in-person support is typically closed. However, limitations were noted, suggesting that caution is needed when interpreting the results of this study. Although such services are incredibly well used, they have received little research attention to date. As such, further investigation into what constitutes helpful and unhelpful peer support is needed.

PMID:36083629 | DOI:10.2196/36432

JMIR Serious Games. 2022 Sep 9;10(3):e36754. doi: 10.2196/36754.

ABSTRACT

BACKGROUND: Human cognitive processing speed is known to decline with age. Human cognitive processing speed refers to the time that an individual takes from receiving a stimulus to reacting to it. Serious games, which are video games used for training and educational purposes, have the potential to improve processing speed. Numerous systematic reviews have summarized the evidence regarding the effectiveness of serious games in improving processing speed, but they are undermined by some limitations.

OBJECTIVE: This study aimed to examine the effectiveness of serious games on the cognitive processing speed of an older adult population living with cognitive impairment.

METHODS: A systematic review of randomized controlled trials (RCTs) was conducted. Two search sources were used in this review: 8 electronic databases and backward and forward reference list checking. A total of 2 reviewers independently checked the eligibility of the studies, extracted data from the included studies, and appraised the risk of bias and quality of the evidence. Evidence from the included studies was synthesized using a narrative and statistical approach (ie, meta-analysis), as appropriate.

RESULTS: Of the 548 publications identified, 16 (2.9%) RCTs eventually met all eligibility criteria. Very-low-quality evidence from 50% (8/16) and 38% (6/16) of the RCTs showed no statistically significant effect of serious games on processing speed compared with no or passive intervention groups (P=.77) and conventional exercises (P=.58), respectively. A subgroup analysis showed that both types of serious games (cognitive training games: P=.26; exergames: P=.88) were as effective as conventional exercises in improving processing speed.

CONCLUSIONS: There is no superiority of serious games over no or passive interventions and conventional exercises in improving processing speed among older adults with cognitive impairment. However, our findings remain inconclusive because of the low quality of the evidence, the small sample size in most of the included studies, and the paucity of studies included in the meta-analyses. Therefore, until more robust evidence is published, serious games should be offered or used as an adjunct to existing interventions. Further trials should be undertaken to investigate the effect of serious games that specifically target processing speed rather than cognitive abilities in general.

TRIAL REGISTRATION: PROSPERO CRD42022301667; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=301667.

PMID:36083623 | DOI:10.2196/36754

Demography. 2022 Sep 9:10216406. doi: 10.1215/00703370-10216406. Online ahead of print.

ABSTRACT

Accurate estimates of subnational populations are important for policy formulation and monitoring population health indicators. For example, estimates of the number of women of reproductive age are important to understand the population at risk of maternal mortality and unmet need for contraception. However, in many low-income countries, data on population counts and components of population change are limited, and so subnational levels and trends are unclear. We present a Bayesian constrained cohort component model for the estimation and projection of subnational populations. The model builds on a cohort component projection framework, incorporates census data and estimates from the United Nation’s World Population Prospects, and uses characteristic mortality schedules to obtain estimates of population counts and the components of population change, including internal migration. The data required as inputs to the model are minimal and available across a wide range of countries, including most low-income countries. The model is applied to estimate and project populations by county in Kenya for 1979-2019 and is validated against the 2019 Kenyan census.

PMID:36083610 | DOI:10.1215/00703370-10216406

JAMA Netw Open. 2022 Sep 1;5(9):e2230925. doi: 10.1001/jamanetworkopen.2022.30925.

ABSTRACT

IMPORTANCE: The association between cancer mortality and risk factors may vary by geography. However, conventional methodological approaches rarely account for this variation.

OBJECTIVE: To identify geographic variations in the association between risk factors and cancer mortality.

DESIGN, SETTING, AND PARTICIPANTS: This geospatial cross-sectional study used county-level data from the National Center for Health Statistics for individuals who died of cancer from 2008 to 2019. Risk factor data were obtained from County Health Rankings & Roadmaps, Health Resources and Services Administration, and Centers for Disease Control and Prevention. Analyses were conducted from October 2021 to July 2022.

MAIN OUTCOMES AND MEASURES: Conventional random forest models were applied nationwide and by US region, and the geographical random forest model (accounting for local variation of association) was applied to assess associations between a wide range of risk factors and cancer mortality.

RESULTS: The study included 7 179 201 individuals (median age, 70-74 years; 3 409 508 women [47.5%]) who died from cancer in 3108 contiguous US counties during 2008 to 2019. The mean (SD) county-level cancer mortality rate was 177.0 (26.4) deaths per 100 000 people. On the basis of the variable importance measure, the random forest models identified multiple risk factors associated with cancer mortality, including smoking, receipt of Supplemental Nutrition Assistance Program (SNAP) benefits, and obesity. The geographical random forest model further identified risk factors that varied at the county level. For example, receipt of SNAP benefits was a high-importance factor in the Appalachian region, North and South Dakota, and Northern California; smoking was of high importance in Kentucky and Tennessee; and female-headed households were high-importance factors in North and South Dakota. Geographic areas with certain high-importance risk factors did not consistently have a corresponding high prevalence of the same risk factors.

CONCLUSIONS AND RELEVANCE: In this cross-sectional study, the associations between cancer mortality and risk factors varied by geography in a way that did not correspond strictly to risk factor prevalence. The degree to which other place-specific characteristics, observed and unobserved, modify risk factor effects should be further explored, and this work suggests that risk factor importance may be a preferable paradigm for selecting cancer control interventions compared with risk factor prevalence.

PMID:36083583 | DOI:10.1001/jamanetworkopen.2022.30925

JAMA Netw Open. 2022 Sep 1;5(9):e2230959. doi: 10.1001/jamanetworkopen.2022.30959.

ABSTRACT

IMPORTANCE: Little is known about the performance of available frailty instruments in estimating patient-relevant outcomes after cardiac surgery.

OBJECTIVE: To examine how well the Johns Hopkins Adjusted Clinical Groups (ACG) frailty indicator, the Hospital Frailty Risk Score (HFRS), and the Preoperative Frailty Index (PFI) estimate long-term patient-centered outcomes after cardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study was conducted in Ontario, Canada, among residents 18 years and older who underwent coronary artery bypass grafting or aortic, mitral or tricuspid valve, or thoracic aorta surgery between October 2008 and March 2017. Long-term care residents, those with discordant surgical encounters, and those receiving dialysis or dependent on a ventilator within 90 days were excluded. Statistical analysis was conducted from July 2021 to January 2022.

MAIN OUTCOMES AND MEASURES: The primary outcome was patient-defined adverse cardiovascular and noncardiovascular events (PACE), defined as the composite of severe stroke, heart failure, long-term care admission, new-onset dialysis, and ventilator dependence. Secondary outcomes included mortality and individual PACE events. The association between frailty and PACE was examined using cause-specific hazard models with death as a competing risk, and the association between frailty and death was examined using Cox models. Areas under the receiver operating characteristic curve (AUROC) were determined over 10 years of follow-up for each frailty instrument.

RESULTS: Of 88 456 patients (22 924 [25.9%] female; mean [SD] age, 66.3 [11.1] years), 14 935 (16.9%) were frail according to ACG criteria, 63 095 (71.3%) according to HFRS, and 76 754 (86.8%) according to PFI. Patients with frailty were more likely to be older, female, and rural residents; to have lower income and multimorbidity; and to undergo urgent surgery. Patients meeting ACG criteria (hazard ratio [HR], 1.66; 95% CI, 1.60-1.71) and those with higher HFRS scores (HR per 1.0-point increment, 1.10; 95% CI, 1.09-1.10) and PFI scores (HR per 0.1-point increment, 1.75; 95% CI, 1.73-1.78) had higher rates of PACE. Similar magnitudes of association were observed for each frailty instrument with death and individual PACE components. The HFRS had the highest AUROC for estimating PACE during the first 2 years and death during the first 4 years, after which the PFI had the highest AUROC.

CONCLUSIONS AND RELEVANCE: These findings could help to tailor the use of frailty instruments by outcome and follow-up duration, thus optimizing preoperative risk stratification, patient-centered decision-making, candidate selection for prehabilitation, and personalized monitoring and health resource planning in patients undergoing cardiac surgery.

PMID:36083582 | DOI:10.1001/jamanetworkopen.2022.30959

J Nephrol. 2022 Sep 9. doi: 10.1007/s40620-022-01427-5. Online ahead of print.

ABSTRACT

BACKGROUND: The use of kidney biopsy in elderly individuals is still matter of discussion. The purpose of this study is to assess the utility of kidney biopsy for the management of glomerulopathies in an Eastern European cohort, targeting patients older than 65 years.

METHODS: This retrospective study included 875 adults (147 older than 65 years), with biopsy-proven glomerulopathies, followed up for 71.1 (95% CI 68.2-73.9) months. The primary endpoint was chronic renal replacement therapy initiation. Statistical evaluation was performed with IBM SPSS software version 20, Analyse-it, and SAS Studio. The Kaplan-Meier method was used to estimate the time to death and the log-rank test was used for comparisons. The multivariate Cox proportional hazard analysis was used to evaluate the risk of death.

RESULTS: Secondary glomerulopathies were more frequent in patients aged > 65 years (52.4% vs. 41.9%, p = 0.004). Membranous nephropathy and amyloidosis were the most frequent primary and secondary glomerulopathies in this age group. Kidney biopsy complications were low (< 4%) in both age groups. In 42% of the elderly, the result of biopsy guided the immunosuppressive therapy. While the all-cause mortality rate was higher (OR 4.2; 95% CI 2.7-6.7; p < 0.0001) in elderly individuals, the rate of renal replacement therapy initiation was similar (31.3 vs 26%; p = 0.1) in both age groups. In the competitive risk analysis, kidney survival was similar irrespective of age [CIF 0.4 (95% CI 0.26-0.53) vs. 0.34 (95% CI 0.28-0.39), p = 0.08]. However, after adjusting for the confounding factors, younger age was associated with an increased risk of renal replacement therapy (HR = 1.57, p = 0.01), along with secondary glomerulopathies.

CONCLUSION: The diagnosis of an underlying glomerulopathy guided the therapy in almost one-half of the elderly patients who underwent a kidney biopsy, provided important prognostic information and had a low complications rate; kidney biopsy may therefore be considered a safe, reliable procedure in the management of glomerulopathies, even in patients over 65 years of age.

PMID:36083532 | DOI:10.1007/s40620-022-01427-5

Ir J Med Sci. 2022 Sep 9. doi: 10.1007/s11845-022-03138-z. Online ahead of print.

ABSTRACT

BACKGROUND: Familial Mediterranean fever (FMF) is an autoimmune disease with periodic fever attacks recurring with mutations in the MEFV gene and chronic inflammation. The new molecule which is formed as a result of the chemical changes made by oxidative free radicals in the albumin molecule during ischemic events is called ischemia modified albumin (IMA).

AIM: The aim of this study is to evaluate the IMA levels as a predictor of the cardiovascular risk factor in FMF patients in the attack-free period and to evaluate the relationship between IMA and inflammation markers.

METHODS: Forty FMF patients without any additional disease, non-smokers, and in their attacks-free period, 40 ankylosing spondylitis patients whose disease activity criteria is less than 4 from Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and 39 healthy adults were included in the cross-sectional analytical research.

RESULTS: The value of IMA was statistically significantly higher in the AS group compared to the control group (p = 0.01). The positive correlations between IMA and ESR, LDL, total cholesterol, triglyceride, CRP, and fibrinogen were statistically significantly determined in FMF patients (respectively; r = 0.594; p < 0.001, r = 0.382; p = 0.015, r = 0.335; p = 0.034, r = 0.363; p = 0.021, r = 0.597; p < 0.001, r = 0.656; p < 0.001). The positive correlations between IMA and ESR, CRP were found in AS patients (respectively; r = 0.383; p = 0.015, r = 0.382; p = 0.015).

CONCLUSION: IMA can be used as a predictor similar to cardiovascular risk factors and it is a precious marker for inflammation. The use of IMA in these fields and the multi-centred and comparative studies about predictability of it may contribute to science.

PMID:36083510 | DOI:10.1007/s11845-022-03138-z