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Large-eddy simulations are used to evaluate mean profile similarity in the convective boundary layer (CBL). Particular care is taken regarding the grid sensitivity of the profiles and the mitigation of inertial oscillations in the simulation spin-up. The nondimensional gradients ϕ for wind speed and air temperature generally align with Monin–Obukhov similarity across cases but have a steeper slope than predicted within each profile. The same trend has been noted in several other recent studies. The Businger-Dyer relations are modified here with an exponential cutoff term to account for the decay in ϕ to first-order approximation, yielding improved similarity from approximately 0.05 z i to above 0.3 z i , where z i is the CBL depth. The necessity for the exponential correction is attributed to an extended transition from surface scaling to zero gradient in the mixed layer, where the departure from Monin–Obukhov similarity may be negligible at the surface but becomes substantial well below the conventional surface layer height of 0.1 z i . [ABSTRACT FROM AUTHOR]

Changes in pharmacokinetics and endogenous metabolites may underlie additive biological effects of concomitant use of antipsychotics and opioids. In this study, we employed untargeted metabolomics analysis and targeted analysis to examine the changes in drug metabolites and endogenous metabolites in the prefrontal cortex (PFC), midbrain, and blood of rats following acute co-administration of quetiapine and methadone. Rats were divided into four groups and received cumulative increasing doses of quetiapine (QTP), methadone (MTD), quetiapine + methadone (QTP + MTD), or vehicle (control). All samples were analyzed using liquid chromatography-mass spectrometry (LC–MS). Our findings revealed increased levels of the quetiapine metabolites: Norquetiapine, O-dealkylquetiapine, 7-hydroxyquetiapine, and quetiapine sulfoxide, in the blood and brain when methadone was present. Our study also demonstrated a decrease in methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in the rat brain when quetiapine was present. Despite these findings, there were only small differences in the levels of 225–296 measured endogenous metabolites due to co-administration compared to single administrations. For example, N-methylglutamic acid, glutaric acid, p-hydroxyphenyllactic acid, and corticosterone levels were significantly decreased in the brain of rats treated with both compounds. Accumulation of serotonin in the midbrain was additionally observed in the MTD group, but not in the QTP + MTD group. In conclusion, this study in rats suggests a few but important additive metabolic effects when quetiapine and methadone are co-administered. [ABSTRACT FROM AUTHOR]

Stack Overflow (SO) is a popular platform among developers seeking advice on various software-related topics, including privacy and security. As for many knowledge-sharing websites, the value of SO depends largely on users' engagement, namely their willingness to answer, comment or post technical questions. Still, many of these questions (including cybersecurity-related ones) remain unanswered, putting the site's relevance and reputation into jeopardy. Hence, it is important to understand users' participation in privacy and security discussions to promote engagement and foster the exchange of such expertise. Objective: Based on prior findings on online social networks, this work elaborates on the interplay between users' engagement and their privacy practices in SO. Particularly, it analyses developers' self-disclosure behaviour regarding profile visibility and their involvement in discussions related to privacy and security. Method: We followed a mixed-methods approach by (i) analysing SO data from 1239 cybersecurity-tagged questions along with 7048 user profiles, and (ii) conducting an anonymous online survey (N=64). Results: About 33% of the questions we retrieved had no answer, whereas more than 50% had no accepted answer. We observed that proactive users tend to disclose significantly less information in their profiles than reactive and unengaged ones. However, no correlations were found between these engagement categories and privacy-related constructs such as perceived control or general privacy concerns. Implications: These findings contribute to (i) a better understanding of developers' engagement towards privacy and security topics, and (ii) to shape strategies promoting the exchange of cybersecurity expertise in SO. [ABSTRACT FROM AUTHOR]

A persistent spatial organization of eddies is identified in the lowest portion of the stably stratified planetary boundary layer. The analysis uses flow realizations from published large-eddy simulations (Sullivan et al. in J Atmos Sci 73(4):1815–1840, 2016) ranging in stability from near-neutral to almost z-less stratification. The coherent turbulent structure is well approximated as a series of uniform momentum zones (UMZs) and uniform temperature zones (UTZs) separated by thin layers of intense gradients that are significantly greater than the mean. This pattern yields stairstep-like instantaneous flow profiles whose shape is distinct from the mean profiles that emerge from long-term averaging. However, the scaling of the stairstep organization is closely related to the resulting mean profiles. The differences in velocity and temperature across the thin gradient layers remain proportional to the surface momentum and heat flux conditions regardless of stratification. The vertical thickness of UMZs and UTZs is proportional to height above the surface for near-neutral and weak stratification, but becomes thinner and less dependent on height as the stability increases. Deviations from the logarithmic mean profiles for velocity and temperature observed under neutral conditions are therefore predominately due to the reduction in eddy size with increasing stratification, which is empirically captured by existing Monin–Obukhov similarity relations for momentum and heat. The zone properties are additionally used to explain trends in the turbulent Prandtl number, thus providing a connection between the eddy organization, mean profiles, and turbulent diffusivity in stably stratified conditions. [ABSTRACT FROM AUTHOR]

The malaria parasite Plasmodium falciparum causes substantial human mortality, primarily in equatorial Africa. Enriched in affected African populations, the B*53 variant of HLA-B, a cell surface protein that presents peptide antigens to cytotoxic lymphocytes, confers protection against severe malaria. Gorilla, chimpanzee, and bonobo are humans' closest living relatives. These African apes have HLA-B orthologs and are infected by parasites in the same subgenus (Laverania) as P. falciparum, but the consequences of these infections are unclear. Laverania parasites infect bonobos (Pan paniscus) at only one (TL2) of many sites sampled across their range. TL2 spans the Lomami River and has genetically divergent subpopulations of bonobos on each side. Papa-B, the bonobo ortholog of HLA-B, includes variants having a B*53-like (B07) peptide-binding supertype profile. Here we show that B07 Papa-B occur at high frequency in TL2 bonobos and that malaria appears to have independently selected for different B07 alleles in the two subpopulations. A variant of MHC class I is protective against severe malaria disease and enriched in affected African populations. Here, Wroblewski et al., characterise the consequences of malaria infection in wild bonobo populations showing that the presence of malaria drives a similar evolution in immune genes. [ABSTRACT FROM AUTHOR]

The current commentary and review examines the potentially protective role of feelings of mattering among elderly people during typical times and the current atypical times associated with the COVID-19 global pandemic. Mattering is the feeling of being important to others in ways that give people the sense that they are valued and other people care about them. We contrast this feeling with messages of not mattering and being expendable and disposable due to ageism, gaps in the provision of care, and apparently economically focused positions taken during the pandemic that disrespect the value, worth, and merits of older persons. We provide a comprehensive review of past research on individual differences in mattering among older adults and illustrate the unique role of mattering in potentially protecting older adults from mental health problems. Mattering is also discussed in terms of its links with loneliness and physical health. This article concludes with a discussion of initiatives and interventions that can be modified and enhanced to instill a sense of mattering among older adults. Key directions for future research are also highlighted along with ways to expand the mattering concept to more fully understand and appreciate the relevance of mattering among older adults. [ABSTRACT FROM AUTHOR]

Introduction: Glaucoma outcomes are closely associated with patients' awareness of the disease. However, little is known about glaucoma awareness and knowledge in Addis Ababa, a densely populated and ethnolinguistically diverse capital city in Ethiopia, the second largest country in Africa. Methods: We performed a cross-sectional survey in the ophthalmology waiting room at St. Paul's Hospital, a tertiary care center in Addis Ababa. Respondents included patients, patient family members, and non-clinical staff. Participants were asked if they had read or heard about glaucoma to gauge basic awareness of the disease; those with awareness were asked to take a quiz to measure their objective glaucoma knowledge. We performed multivariable regression to identify factors associated with glaucoma awareness, quiz performance, and self-rated ability to use eye drops. Results: Of 298 respondents, 145 (48.7%) were female, and the average age was 44.9 ± 17.2 years. A majority (167; 56.0%) had primary school or less than primary school education. Only 131 (44.0%) had basic glaucoma awareness. Of these, 95 (72.5%) knew that glaucoma causes permanent vision loss, 103 (78.6%) knew glaucoma is often asymptomatic in early stages, 62 (47.3%) identified elevated intraocular pressure as a glaucoma risk factor, and 124 (94.7%) knew glaucoma was treatable. A majority of this subset (126; 96.2%) said they would be willing to use medicated eye drops, and 130 (99.2%) indicated a willingness to undergo surgery if recommended. Education level was independently associated with glaucoma awareness (p < 0.001) and glaucoma quiz performance (p = 0.03). Conclusion: In a population sample from an ophthalmology waiting room in Addis Ababa, glaucoma awareness was poor and most strongly associated with education level. Educational interventions at public health and provider-patient levels are warranted. Our results suggest high receptiveness to both medical and surgical treatment. [ABSTRACT FROM AUTHOR]

Background: We aimed to compare patient characteristics and outcome of patients who had either undergone pulmonary vein isolation (PVI) or AV-node ablation (AVN) to control AF-related symptoms.Methods: From the German Ablation Registry, we analyzed data of 4444 patients (95%) who had undergone PVI and 234 patients (5%) with AVN.Results: AVN patients were on average 10 years older than PVI patients (71 ± 10 vs. 61 ± 10 years, p < 0.001) with 33% aged > 75 years. AVN patients had significantly more cardiovascular comorbidities (diabetes 21% vs. 8%, renal insufficiency 24% vs. 3%, underlying heart disease 80% vs. 36%, severely reduced left ventricular function 28% vs. 1%, all p < 0.001). Significantly more PVI patients had paroxysmal AF (63% vs. 18%, p < 0.001), and more AVN patients had long-standing persistent AF (44% vs. 7%, p < 0.001). At 1-year follow-up, mortality in the AVN group was much higher (Kaplan-Meier estimates 9.8% vs. 0.5%). 20% of PVI patients had undergone another ablation vs. 3% AVN patients (p < 0.001). Symptomatic improvement was equally achieved in about 80%. Re-hospitalization for cardiovascular reasons occurred significantly more often in PVI vs. AVN patients (31% vs. 18%, p < 0.001).Conclusion: In the large German Ablation Registry, AVN ablation was performed much less frequently than PVI for symptomatic treatment of AF and typically in older patients with more comorbidity. Symptomatic improvement was similar in both groups. Hospitalizations for cardiovascular reasons were lower in AVN patients despite older age and more cardiovascular comorbidities. 20% of PVI patients had undergone at least one re-ablation. [ABSTRACT FROM AUTHOR]

Purpose and Hypothesis: Subsidence is a known reason for early failure of total hip arthroplasty (THA). In particular, cementless THA might be vulnerable to migration. The present study analysed femoral stem subsidence after primary cementless THA. Prosthetic and anatomical risk factors for early femoral stem subsidence were evaluated.Methods: Two hundred thirty-one consecutive patients who underwent primary cementless THA in a single centre were retrospectively analysed. Post-operative results were evaluated in consideration of prosthetic and anatomical properties in correlation with subsidence on standing pelvic anteroposterior radiographs. Stem type and design, demographic data, BMI, canal flare index (CFI) and canal fill ratio (CFR) were evaluated.Results: The subsidence rate was significantly higher in collarless femoral stems [3.1 mm (SD 2.8 mm) vs. 1.9 mm (SD 1.5 mm); p = 0.013] while the anatomical type of the proximal femur as described by the canal flare index did not influenced subsidence (p = 0.050). Also, the canal fill ratio showed no significant correlation with subsidence at any level.Conclusions: In the present study, stem subsidence was significantly higher in the collarless group compared to collared stems. No anatomical parameter (CFI and CFR) could be identified as risk factor for subsidence. Neither age nor BMI influenced subsidence in this cohort. Still, subgroup analysis indicated a sex-dependent role of BMI. Prospective studies of large cohorts should address the problem of subsidence in the future.Level Of Evidence: Retrospective therapeutic study, Level IV. [ABSTRACT FROM AUTHOR]

Rationale: Oxytocin is a neuropeptide widely recognized for its role in regulating social and reproductive behavior. Increasing evidence from animal models suggests that oxytocin also modulates reward circuitry in non-social contexts, but evidence in humans is lacking. Objectives: We examined the effects of oxytocin administration on reward circuit function in 18 healthy men as they performed a monetary incentive task. Methods: The blood oxygenation level-dependent (BOLD) signal was measured using functional magnetic resonance imaging in the context of a randomized, double-blind, placebo-controlled, crossover trial of intranasal oxytocin. Results: We found that oxytocin increases the BOLD signal in the midbrain (substantia nigra and ventral tegmental area) during the late phase of the hemodynamic response to incentive stimuli. Oxytocin's effects on midbrain responses correlated positively with its effects on positive emotional state. We did not detect an effect of oxytocin on responses in the nucleus accumbens. Whole-brain analyses revealed that oxytocin attenuated medial prefrontal cortical deactivation specifically during anticipation of loss. Conclusions: Our findings demonstrate that intranasal administration of oxytocin modulates human midbrain and medial prefrontal function during motivated behavior. These findings suggest that endogenous oxytocin is a neurochemical mediator of reward behaviors in humans-even in a non-social context-and that the oxytocinergic system is a potential target of pharmacotherapy for psychiatric disorders that involve dysfunction of reward circuitry. [ABSTRACT FROM AUTHOR]

Purpose: Femoral defects often make it difficult to achieve sufficient fixation of the stem during revision surgery. No clinical studies comparing modular stems are available and differentiated recommendations are rare. The aim of this study was to compare the fixation of different revision stems in an experimental and standardised manner. Methods: Segmental AAOS type I and III defects were reproduced in four femur pairs and two modular stems of different shape (cylindrical and conical) were implanted. Interfacial stem-bone movements were measured under axial torque application to analyze the stem fixation depending on defect extension. Results: Both stems showed adequate fixation in AAOS type I defect. The defect extension significantly reduced the fixation of both implants. The fixation pattern changed significantly for the cylindrical-shaped stem but was maintained for the conical-shaped stem. Conclusions: Shape as well as the extension of femoral defect have an impact on primary fixation. A type I defect seems to be bridgeable for both stems albeit in a different way. In contrast, stem-demanding activities during the healing phase have to be avoided for the conical-shaped stem in a type III defect, whereas the cylindrical-shaped stem has already ceased to be sufficiently stable in this case. [ABSTRACT FROM AUTHOR]