A magnetohydrodynamic model that includes a complete electrical conductivity tensor is used to estimate conditions for photospherically driven, linear, non-plane Alfvenic oscillations extending from ...the photosphere to the lower corona to drive a chromospheric heating rate due to Pedersen current dissipation that is comparable to the observed net chromospheric radiative loss of ~107 erg cm--2 s--1. The heating rates due to electron current dissipation in the photosphere and corona are also computed. The wave amplitudes are computed self-consistently as functions of an inhomogeneous background (BG) atmosphere. The effects of the conductivity tensor are resolved numerically using a resolution of 3.33 m. The oscillations drive a chromospheric heating flux F Ch ~ 107-108 erg cm--2 s--1 at frequencies Delta *n ~ 102-103 mHz for BG magnetic field strengths B 700 G and magnetic field perturbation amplitudes ~0.01-0.1 B. The total resistive heating flux increases with Delta *n. Most heating occurs in the photosphere. Thermalization of Poynting flux in the photosphere due to electron current dissipation regulates the Poynting flux into the chromosphere, limiting F Ch. F Ch initially increases with Delta *n, reaches a maximum, and then decreases with increasing Delta *n due to increasing electron current dissipation in the photosphere. The resolution needed to resolve the oscillations increases from ~10 m in the photosphere to ~10 km in the upper chromosphere and is Delta *n--1/2. Estimates suggest that these oscillations are normal modes of photospheric flux tubes with diameters ~10-20 km, excited by magnetic reconnection in current sheets with thicknesses ~0.1 km.
Total joint arthroplasty (TJA) is one of the most common surgical procedures in the United States; however, racial and ethnic disparities in utilizations and outcomes have been well documented. This ...systematic review and meta-analysis investigated associations between race/ethnicity and several metrics in total hip arthroplasty (THA) and total knee arthroplasty (TKA).
In August 2021, PubMed, Scopus, CINAHL, and SPORTDiscus databases were queried. Sixty three studies investigating racial/ethnic disparities in TJA utilizations, complications, mortalities, lengths of stay (LOS), discharge dispositions, readmissions, and reoperations were included. Study quality was assessed using a modified Newcastle-Ottawa Scale.
A majority of studies demonstrated disparities in TJA utilizations and outcomes. Black patients exhibited higher rates of 30-day complications (THA odds ratio OR 1.18, 95% confidence interval CI 1.08-1.29; TKA OR 1.20, 95% CI 1.10-1.31), 30-day mortality (THA OR 1.27, 95% CI 1.08-1.48), prolonged LOS (THA mean difference MD +0.27 days, 95% CI 0.21-0.33; TKA MD +0.30 days, 95% CI 0.20-0.40), nonhome discharges (THA OR 1.47, 95% CI 1.37-1.57; TKA OR 1.65, 95% CI 1.38-1.96), and 30-day readmissions (THA OR 1.13, 95% CI 1.08-1.19; TKA OR 1.19, 95% CI 1.16-1.21) than White patients. Rates of complications (THA 1.18, 95% CI 1.03-1.36), prolonged LOS (TKA MD +0.20 days, 95% CI 0.17-0.23), and nonhome discharges (THA OR 1.26, 95% CI 1.10-1.45; TKA OR 1.37, 95% CI 1.22-1.53) were also increased among Hispanic patients, while Asian patients experienced longer LOS (TKA MD +0.09 days, 95% CI 0.05-0.12) but fewer readmissions. Outcomes among American Indian-Alaska Native and Pacific Islander patients were infrequently reported but similarly inequitable.
Racial and ethnic disparities in TJA utilizations and outcomes are apparent, with minority patients often demonstrating lower rates of utilizations and worse postoperative outcomes than White patients. Continued research is needed to evaluate the efficacy of recent efforts dedicated to eliminating inequalities in TJA care.
IV.
A magnetohydrodynamic model is used to determine conditions under which the Lorentz force accelerates plasma to type 2 spicule speeds in the chromosphere. The model generalizes a previous model to ...include a more realistic pre-spicule state, and the vertical viscous force. Two cases of acceleration under upper chromospheric conditions are considered. The magnetic field strength for these cases is < or =, slant12.5 and 25 G. Plasma is accelerated to terminal vertical speeds of 66 and 78 km s super(-1) in 100 s, compared with 124 and 397 km s super(-1) for the case of zero viscosity. The flows are localized within horizontal diameters ~80 and 50 km. The total thermal energy generated by viscous dissipation is ~10 times larger than that due to Joule dissipation, but the magnitude of the total cooling due to rarefaction is gap this energy. Compressive heating dominates during the early phase of acceleration. The maximum energy injected into the corona by type 2 spicules, defined as the energy flux in the upper chromosphere, may largely balance total coronal energy losses in quiet regions, possibly also in coronal holes, but not in active regions. It is proposed that magnetic flux emergence in intergranular regions drives type 2 spicules.
The RV144 Thai trial HIV-1 vaccine of recombinant poxvirus (ALVAC) and recombinant HIV-1 gp120 subtype B/subtype E (B/E) proteins demonstrated 31% vaccine efficacy. Here we design an ...ALVAC/Pentavalent B/E/E/E/E vaccine to increase the diversity of gp120 motifs in the immunogen to elicit a broader antibody response and enhance protection. We find that immunization of rhesus macaques with the pentavalent vaccine results in protection of 55% of pentavalent-vaccine-immunized macaques from simian-human immunodeficiency virus (SHIV) challenge. Systems serology of the antibody responses identifies plasma antibody binding to HIV-infected cells, peak ADCC antibody titres, NK cell-mediated ADCC and antibody-mediated activation of MIP-1β in NK cells as the four immunological parameters that best predict decreased infection risk that are improved by the pentavalent vaccine. Thus inclusion of additional gp120 immunogens to a pox-prime/protein boost regimen can augment antibody responses and enhance protection from a SHIV challenge in rhesus macaques.
A 2.5D, time-dependent magnetohydrodynamic model is used to test the proposition that observed type II spicule velocities can be generated by a Lorentz force under chromospheric conditions. It is ...found that current densities localized on observed space and time scales of type II spicules and that generate maximum magnetic field strengths < or =, slant 50 G can generate a Lorentz force that accelerates plasma to terminal velocities similar to those of type II spicules. Maximum vertical flow speeds are - 150-460 km s super(-1), horizontally localized within ~2.5-10 km from the vertical axis of the spicule, and comparable to slow solar wind speeds, suggesting that significant solar wind acceleration occurs in type II spicules. Horizontal speeds are ~20 times smaller than vertical speeds. Terminal velocity is reached ~100 s after acceleration begins. The increase in the mechanical and thermal energy of the plasma during acceleration is (2-3) x 10 super(22) ergs. The radial component of the Lorentz force compresses the plasma during the acceleration process by factors as large as ~ 100. The Joule heating flux generated during this process is essentially due to proton Pedersen current dissipation and can be ~0.1-3.7 times the heating flux of ~10 super(6) ergs cm super(-2) s super(-1) associated with middle-upper chromospheric emission. About 84%-94% of the magnetic energy that accelerates and heats the spicules is converted into bulk flow kinetic energy.
Reportedly 2% to 5.7% of total knee arthroplasties (TKAs) require revision within 5 years. The purpose of this study was to determine whether blacks are at higher risk of TKA revision than whites in ...the United States.
We performed a systematic review of English-language articles published from 2000 to 2015. Study inclusion criteria were (1) performance of the study in the United States, (2) TKA as the primary procedure studied, (3) a follow-up period at least 2 years, (4) reporting of revision rates, and (5) analysis of patient race as an independent predictor of revision. We then performed a random-effects meta-analysis to calculate a pooled hazard ratio for TKA revision in blacks compared with whites.
A total of 4,286 studies were identified and screened by title; 106, by abstract; and 24, by full text. Six studies met the inclusion criteria. Only 4 of the 6 studies could undergo meta-analysis because of overlapping study populations in 3 of them. The meta-analysis represented 451,960 patients who underwent TKA, of whom 28,772 (6.4%) were black. Of the total, 31,568 patients (7.0%) underwent revision surgery. The risk of revision TKA was significantly higher among blacks than whites (pooled hazard ratio, 1.38; 95% confidence interval, 1.20 to 1.58; p < 0.001). Analysis of the 3 studies with overlapping study populations demonstrated discordant results as a result of adjustment compared with non-adjustment for insurance eligibility, a surrogate for socioeconomic status.
Blacks in the United States are at higher risk of revision TKA than whites. Socioeconomic status contributed to revision risk and is an important confounder in analyses of race.
Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Multisystem, multi-level interventions are required to enable resilient, nurturing environments for children facing adversity. This study assesses parenting behavior associated with participation in ...a community-based, adapted microfinance program, and mediated by program-affiliated social capital, maternal depression and self-esteem among Kenyan women. Participants in the intervention, Kuja Pamoja kwa Jamii (KPJ, Swahili for “Come Together to Belong”), gather weekly to engage in trainings and group-based microfinance. Groups selected for the study had participated in the program for 0–15 months at the time of the first interview. Women (n = 400) completed surveys in June 2018 and June 2019. Measures included duration of program exposure, group-affiliated social capital (i.e. trust, belonging, cohesion, and expectation of mutual benefit), depression, self-esteem, and conflict tactics. We used regression analyses and generalized structural equation models to explore associations between program exposure, social capital, psychosocial variables and child maltreatment. Each standard deviation increase in duration of program exposure decreased odds of child physical abuse by 40% and child neglect by 35%. Each standard deviation in the social capital index predicted a significant reduction in odds of child physical abuse (aOR: 0.67), and child neglect (aOR: 0.71). Self-esteem and depression fully mediated observed associations between social capital and child maltreatment. Findings recommend further investigation of the potential for adapted microfinance programs to deliver parenting interventions, improve mental health and foster resilience-enabling social capital. A randomized control trial is required to validate the potential of the assessed intervention to improve parenting behaviors and supportive social conditions.
Globally there is high morbidity due to mental illnesses, necessitating research on positive mental health and new models of mental health promotion. This study investigates the mediating role of ...spirituality to known pathways between childhood social exposures and adult mental health outcomes—hope, meaning in life and depression among young Kenyan men. Using the “religion as attachment” framework, we investigate whether childhood attachment conditions predict lower scores of daily spiritual experiences, and whether this pathway mediates associations between childhood attachment conditions and current depression, meaning in life, and hope. Spirituality significantly mediated associations between childhood attachments and adult mental health.
Summary
Over the past four decades, group-based microfinance programs have spread rapidly throughout south Asia, sub-Saharan Africa and Latin America. Recent evaluations of the programs have ...identified social capital as a common byproduct of frequent association by members, increasing trust, belonging and normative influence. Concurrently, social capital is increasingly recognized as an important health determinant. We present an overview of a program intervention operating in Kenya that utilizes a microfinance approach to produce social capital, and seeks to leverage that social capital to promote health at three levels—the village, group, and individual. A theory of change is presented for each of these three levels, demonstrating conceptually and with program examples how social capital can be applied to promote health. Related social theories and approaches, further research and program directions are given for each of the three levels. We identify potential to improve a broad range of health outcomes through this innovative model, which requires engagement with health promotion researchers and planners in low- and middle-income countries for further refinement and validation.
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