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A flow over hot water film in horizontal channel (Poiseuille–Benard flow) is studied experimentally and by means of CFD. Averaged temperature and concentration fields were measured in central transverse plane using RTD and capacitive humidity probe for different Ri = Gr/Re2. A similarity of thermal and concentration field is discussed and the influence of thermal and humidity field by radiative heat transfer is investigated since it has a considerable effect. Same cases are modeled by CFD in commercial code Star-CCM+. Simulated thermal and concentration fields shows similar character as those from measurements when radiative heat transfer mode is considered.

An experimental study was conducted to investigate the thermal field of low-speed flow of moistair in a horizontal rectangular duct, uniformly heated from below (Poiseuille–Benard flow). Averaged temperature fields were measured in vertical mid-plane using thermocouples. The buoyancy-induced secondary flow is interacting with forced Poiseuille flow which leads to complex flow behaviour with flow reversal along the top surface. Two types of bottom boundary conditions were examined: aluminium plate (only heat transfer) and water film (simultaneous heat and mass transfer) heated to the same temperature. Presence of mass transfer causes stronger transient behaviour above the bottom surface and enhancing of heat transfer, but the overall character of the thermal field remains the same as in case of heat transfer only.

The article deals with the analysis of CFD results of the turbulent synthetic jet. The numerical simulation of Large Eddy Simulation (LES) using commercial solver ANSYS CFX has been performed. The unsteady flow field is studied from the point of view of identification of the moving vortex ring, which has been identified both on the snapshots of flow field using swirling-strength criterion and using the Dynamic Mode Decomposition (DMD) of five periods. It is shown that travelling vortex ring vanishes due to interaction with vortex structures in the synthesised turbulent jet. DMD modes with multiple of the basic frequency of synthetic jet, which are connected with travelling vortex structure, have largest DMD amplitudes.

Background: To determine differences in baseline characteristics and outcomes of leadless pacemaker implantation based on sex., Methods: For the purpose of this study, data were extracted from the National Inpatient Sample database for years 2016-2020. The study group was then stratified based on sex. Baseline characteristics and in-hospital outcomes including complications were then analyzed in each group. Multivariable logistic regression models were created to analyze the association of sex with important outcomes of mortality, major complications (defined as pericardial effusion requiring intervention and any vascular complication), prolonged length of stay (defined as > 6 days), and increased cost of hospitalization (defined as median cost > 34,098$) after leadless pacemaker implantation., Results: A total of 29,000 leadless pacemakers (n in women = 12,960, 44.7%) were implanted during our study period. Women were found to have an increased burden of co-morbidities as compared to men. In the adjusted analysis, the likelihood of mortality (aOR 1.27, 95% CI 1.14-1.43), major complications (aOR 1.07, 95% CI 0.98-1.18), prolonged length of stay (aOR 1.09, 95% CI 1.04-1.15), and increased hospitalization cost (aOR 1.14, 95% CI 1.08-1.20) were higher in women as compared to men after leadless pacemaker implantation., Conclusion: Important and significant differences exist in leadless pacemaker implantation in women as compared to men. These findings highlight the need for evaluating etiologies behind such differences with a goal of improving outcomes in all patients after leadless pacemaker implantation., (© 2024. The Author(s).)

Background: Coronavirus disease 2019 [severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)] infection at varying time points during the pregnancy can influence antibody levels after delivery. We aimed to examine SARS-CoV-2 IgG, IgM and IgA receptor binding domain of the spike protein and nucleocapsid protein (N-protein) reactive antibody concentrations in maternal blood, infant blood and breastmilk at birth and 6 weeks after SARS-CoV-2 infection in early versus late gestation., Methods: Mothers with SARS-CoV-2 infection during pregnancy were enrolled between July 2020 and May 2021. Maternal blood, infant blood and breast milk samples were collected at delivery and 6 weeks postpartum. Samples were analyzed for SARS-CoV-2 spike and N-protein reactive IgG, IgM and IgA antibodies. Antibody concentrations were compared at the 2 time points and based on trimester of infection ("early" 1st/2nd vs. "late" 3rd)., Results: Dyads from 20 early and 11 late trimester infections were analyzed. For the entire cohort, there were no significant differences in antibody levels at delivery versus 6 weeks with the exception of breast milk levels which declined over time. Early gestation infections were associated with higher levels of breastmilk IgA to spike protein ( P = 0.04). Infant IgG levels to spike protein were higher at 6 weeks after late infections ( P = 0.04). There were strong correlations between maternal and infant IgG levels at delivery ( P < 0.01), and between breastmilk and infant IgG levels., Conclusions: SARS-CoV-2 infection in early versus late gestation leads to a persistent antibody response in maternal blood, infant blood and breast milk over the first 6 weeks after delivery., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background Information on maternal and fetal outcomes of pregnancy in women with D-transposition of the great arteries is limited. We conducted a systematic literature review on pregnancies in women with transposition of the great arteries after atrial and arterial switch operations to better define maternal and fetal risk. Methods and Results A systematic review was performed on studies between 2000 and 2021 that identified 676 pregnancies in 444 women with transposition of the great arteries. A total of 556 pregnancies in women with atrial switch operation were tolerated by most cases with low mortality (0.6%). Most common maternal complications, however, were arrhythmias (9%) and heart failure (8%) associated with serious morbidity in some patients. Worsening functional capacity, right ventricular function, and tricuspid regurgitation occurred in ≈20% of the cases. Rate of fetal and neonatal mortality was 1.4% and 0.8%, respectively, and rate of prematurity was 32%. A total of 120 pregnancies in women with arterial switch operation were associated with no maternal mortality, numerically lower rates of arrhythmias and heart failure (6% and 5%, respectively), significantly lower rate of prematurity (11%; P <0.001), and only 1 fetal loss. Conclusions Pregnancy is tolerated by most women with transposition of the great arteries and atrial switch operation with low mortality but important morbidity. Most common maternal complications were arrhythmias, heart failure, worsening of right ventricular function, and tricuspid regurgitation. There was also a high incidence of prematurity and increased rate of fetal loss and neonatal mortality. Outcome of pregnancy in women after arterial switch operations is more favorable, with reduced incidence of maternal complications and fetal outcomes similar to women without underlying cardiac disease.

Objective: SARS-CoV-2 infection induces significant inflammatory cytokine production in adults, but infant cytokine signatures in pregnancies affected by maternal SARS-CoV-2 are less well characterized. We aimed to evaluate cytokine profiles of mothers and their infants following COVID-19 in pregnancy., Study Design: Serum samples at delivery from 31 mother-infant dyads with maternal SARS-CoV-2 infection in pregnancy (COVID) were examined in comparison to 29 control dyads (Control). Samples were evaluated using a 13-plex cytokine assay., Results: In comparison with controls, interleukin (IL)-6 and interferon gamma-induced protein 10 (IP-10) were higher in COVID maternal and infant samples (p &lt; 0.05) and IL-8 uniquely elevated in COVID infant samples (p &lt; 0.05). Significant elevations in IL-6, IP-10, and IL-8 were found among both early (1st/2nd Trimester) and late (3rd Trimester) maternal SARS-CoV-2 infections., Conclusions: Maternal SARS-CoV-2 infections throughout gestation are associated with increased maternal and infant inflammatory cytokines at birth with potential to impact long-term infant health., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Influenza A virus's (IAV's) frequent genetic changes challenge vaccine strategies and engender resistance to current drugs. We sought to identify conserved and essential RNA secondary structures within IAV's genome that are predicted to have greater constraints on mutation in response to therapeutic targeting. We identified and genetically validated an RNA structure (packaging stem-loop 2 (PSL2)) that mediates in vitro packaging and in vivo disease and is conserved across all known IAV isolates. A PSL2-targeting locked nucleic acid (LNA), administered 3 d after, or 14 d before, a lethal IAV inoculum provided 100% survival in mice, led to the development of strong immunity to rechallenge with a tenfold lethal inoculum, evaded attempts to select for resistance and retained full potency against neuraminidase inhibitor-resistant virus. Use of an analogous approach to target SARS-CoV-2, prophylactic administration of LNAs specific for highly conserved RNA structures in the viral genome, protected hamsters from efficient transmission of the SARS-CoV-2 USA&#95;WA1/2020 variant. These findings highlight the potential applicability of this approach to any virus of interest via a process we term 'programmable antivirals', with implications for antiviral prophylaxis and post-exposure therapy., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Background: Coronavirus disease 2019 (COVID-19) is a pandemic that has and will continue to affect many pregnant women. Knowledge regarding the risk of vertical transmission is limited. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) real-time reverse transcriptase-polymerase chain reaction (RT-PCR) of nasopharyngeal swabs typically have been used to confirm the diagnosis among infants, but whether the virus can be detected in other biological specimens, and therefore potentially transmitted in other ways, is unknown. Positive SARS-CoV-2 RT-PCR has been reported from feces and urine from adult patients. We hypothesize that the presence of SARS-CoV-2 in infant urine and fecal samples after prenatal COVID-19 exposure is low., Methods: We examined the presence of SARS-CoV-2 RNA using RT-PCR in urine and fecal samples among 42 infants born to SARS-CoV-2-infected mothers during different stages of pregnancy., Results: A urine sample was collected from 39 of 42 infants and fecal samples from all 42 infants shortly after birth. Although the majority of the women had the symptomatic disease (85.6%), we were unable to detect the presence of SARS-CoV-2 virus from any infant urine or fecal samples., Conclusions: SARS-CoV-2 was not detected in infant urine or feces after maternal infection during pregnancy, providing further evidence for low rates of perinatal transmission., Impact: SARS-CoV-2 was not detected in the urine or feces of infants of mothers with COVID-19 during various time points in pregnancy. This study provides further evidence for low rates of perinatal transmission of SARS-CoV-2. Results help to provide guidance on perinatal care practices for infants exposed to COVID-19 in utero., (© 2021. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)

Importance: The use of statins in patients with symptomatic peripheral artery disease remains suboptimal despite strong clinical practice guideline recommendations; however, it is unknown whether rates are associated with substantial improvements after lower extremity revascularization., Objective: To report longitudinal trends of statin use in patients with peripheral artery disease undergoing lower extremity revascularization and to identify the clinical and procedural characteristics associated with prescriptions for new statin therapy at discharge., Design, Setting, and Participants: This was a retrospective cross-sectional study using data from the Vascular Quality Initiative registry of patients who underwent lower extremity peripheral artery disease revascularization from January 1, 2014, through December 31, 2019. The Vascular Quality Initiative is a multicenter registry database including academic and community-based hospitals throughout the US. Patients aged 18 years or older undergoing lower extremity revascularization with available statin data (preprocedure and postprocedure) were included. Those not receiving statin therapy for medical reasons were excluded from final analyses., Exposures: Patients undergoing lower extremity revascularization for whom statin therapy is indicated., Main Outcomes and Measures: Multivariate logistic regression was used to determine the clinical and procedural characteristics associated with new statin prescription for patients not already taking a statin preprocedure. The overall rates of statin prescription as well as rates of new statin prescription at discharge were determined. In addition, the clinical, demographic, and procedural characteristics associated with new statin prescription were analyzed., Results: There were 172 025 procedures corresponding to 125 791 patients (mean [SD] age, 67.7 [11.0] years; 107 800 men [62.7%]; and 135 405 White [78.7%]) included in the analysis. Overall rates of statin prescription at discharge improved from 17 299 of 23 093 (75%) in 2014 to 29 804 of 34 231 (87%) in 2019. However, only 12 790 of 42 020 patients (30%) not already taking a statin at the time of revascularization during the study period were newly discharged with a statin medication. New statin prescription rates were substantially lower after endovascular intervention (7745 of 29 581 [26%]) than after lower extremity bypass (5045 of 12 439 [41%]). Body mass index of 30 or greater (odds ratio [OR], 1.13; 95% CI, 1.04-1.24; P < .001), diabetes (diet-controlled vs no diabetes, OR, 1.22; 95% CI, 1.05-1.41; P = .01), smoking (current vs never, OR, 1.32; 95% CI, 1.21-1.45; P < .001), hypertension (OR, 1.19; 95% CI, 1.09-1.29; P < .001), and coronary heart disease (OR, 1.26; 95% CI, 1.17-1.35; P < .001) were associated with an increased likelihood of new statin prescription after endovascular intervention, whereas female sex, older age, antiplatelet use, and prior peripheral revascularization were associated with a decreased likelihood., Conclusions and Relevance: In this cross-sectional study, although statin use was associated with a substantial improvement after lower extremity revascularization, more than two-thirds of patients not already taking a statin preprocedure remained not taking a statin at discharge. Further investigations to understand the clinical implications of these findings and develop clinician- and system-based interventions are needed.

Heat storage efficiency is required to maximize the potential of combined heat and power generation or renewable energy sources for heating. Using a phase change material (PCM) could be an attractive choice in several instances. Commercially available paraffin-based PCM was investigated using T-history method with sufficient agreement with the data from the manufacturer. The introduced LHTES with cylindrical capsules is simple and scalable in capacity, charging/discharging time, and temperature level. The overall stored energy density is 9% higher than the previously proposed design of similar design complexity. The discharging process of the designed latent heat thermal energy storage (LHTES) was evaluated for two different flow rates. The PCM inside the capsules and heat transfer fluid (HTF) temperature, as well as the HTF flow rate, were measured. The lumped parameter numerical model was developed and validated successfully. The advantage of the proposed model is its computational simplicity, and thus the possibility to use it in simulations of a whole heat distribution network. The so-called state of charge (SoC), which plays a crucial role in successful heat storage management, is a part of the evaluation of both experimental and computational data., (© 2021. The Author(s).)

Rationale: African-American mothers in the U.S. experience high rates of stress, placing them at risk for depression, anxiety, and preterm births, and their children at risk for poor social-emotional development later in childhood. Yet, few studies have developed and tested family-based interventions that target optimal management of stress in this population., Objective: The current mixed methods study examined whether a six-week family-based intervention (e.g., cognitive behavioral stress management intervention component for mothers and mindfulness-based kindness curriculum for their children) was effective in improving psychosocial outcomes among low-income African-American mothers and increasing prosocial behaviors in their children., Method: Seventy-two mothers (28% pregnant, 72% postpartum) completed pre- and post-intervention assessments of stress, depression, anxiety, and self-efficacy for stress management. Prosocial behaviors for 38 of their children (3-10 years of age) were also assessed via mother's self-report and two observational child assessments of sharing and helping behaviors. Qualitative interviews at post-intervention and reunion focus groups (up to two years later) were also conducted., Results: Mothers showed significant reductions in perceived stress, depressive symptoms, and anxiety, as well as improved self-efficacy for stress management at post-intervention. Although observational assessments of children's sharing and helping behaviors did not change, mothers' qualitative responses indicated improvements in their child's prosocial behaviors at home. Qualitative responses also revealed unique stressors that mothers experienced, the short- and long-term impact of these interventions on mothers and their children, and program recommendations., Conclusions: These results support the efficacy of family-based stress management interventions in this at-risk population., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Health care workers (HCWs) can acquire and transmit influenza to their patients and coworkers, even while asymptomatic. The U.S. Healthy People 2010 initiative set a national goal of 60% coverage for HCW influenza vaccination by 2010. Yet vaccination rates remain low. In the 2008-2009 influenza season, Flushing Hospital Medical Center (FHMC; New York) adopted a "push/pull" point-of-dispensing (POD) vaccination model that was derived from emergency preparedness planning for mass vaccination and/or prophylaxis to respond to an infectious disease outbreak, whether occurring naturally or due to bioterrorism. LAUNCH OF THE HCW VACCINATION PROGRAM: In mid-September 2008, a two-week HCW vaccination program was launched using a sequential POD approach. In Push POD, teams assigned to specific patient units educated all HCWs about influenza vaccination and offered on-site vaccination; vaccinated HCWs received a 2009 identification (ID) validation sticker. In Pull POD, HCWs could enter the hospital only through one entrance; all other employee entrances were "locked down." A 2009 ID validation sticker was required for entry and to punch in for duty. Employees without the new validation sticker were directed to a nearby vaccination team. After the Push/Pull POD was completed, the employee vaccination drive at FHMC was continued for the remainder of the influenza season by the Employee Health Service., Results: Using this model, in two days 72% of the employees were reached, with 54% of those reached accepting vaccination., Conclusions: This model provides a novel approach for institutions to improve their HCW influenza vaccination rates within a limited period through exercising emergency preparedness plans for infectious disease outbreaks.