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Oscillating water column (OWC) devices utilise wave-induced oscillation of water column in partially submerged chambers to extract energy of waves in ocean. The principal aim of this paper is to investigate scaling effects of two-dimensional OWC through numerical simulations. The fluid motion under waves is simulated by solving the two-dimensional incompressible Reynolds-Averaged Navier-Stokes equations using finite element method under Arbitrary Lagrangian-Eulerian scheme. To investigate scaling effects, the waves and the OWC are scaled up or down according to Froude number similarity. The turbine is scaled up or down using three different scaling methods: (1) Turbine coefficient remains unchanged, i.e. not scaling the turbine at all; (2) Equivalent pneumatic damping coefficient of the turbine is constant and (3) the two-dimensional turbine coefficient is constant. The numerical results show that method (2) has the smallest effects on the best hydraulic efficiency and method (3) has the smallest effects on the best performance wave number, i.e. the wave number where the OWC receives the largest percentage of the wave energy. The worst scaling method is not scaling the turbine. Because the best performance wave number varies with the model scale in method (1) and (2), it is very likely the scaling effects of the model scale on the hydrodynamic performance at different wave numbers are different from each other. In addition, the effects of the wave height and the chamber volume are studied. Increasing chamber volume causes a reduction of the best performance, however it may improve general performance of OWC because it increases the frequency band of waves with high hydraulic efficiency. Increasing wave height causes a reduction of the hydraulic efficiency.

Background With recent COVID-19 vaccination rates relatively high in the USA, the USA still maintains the most documented cases globally,[1] even though COVID-19 cases, hospitalization, and mortality have been declining. However, the health burden has been largely felt in communities involving racial and ethnic minorities. Thus, in order to provide a clearer picture of what is happening in Black, Indigenous, and people of color communities, we examined the racial/ethnic differences of monthly COVID-19 deaths in Connecticut. Methods This is an epidemiological study analyzing mortality data from March 1, 2020, to February 28, 2021, obtained from the Connecticut State Department of Public Health. The data include cause of death (COVID-19 death identified by ICD-10 code U071), race/ethnicity (non-Hispanic White (White), non-Hispanic Black (Black), and Hispanic), sex, and age. Both crude and age-adjusted rates were reported by racial/ethnic groups. To compare age-adjusted rates between racial groups, with estimated age-adjusted death counts as outcomes, between-racial group rate ratios, 95% confidence intervals, and p values significant at

Tamsulosin is the most widely used alpha-1 blocker medication for managing benign prostatic hyperplasia (BPH) as indicated in the current practice guideline. The aim of this study was to compare all-cause medical costs and BPH-specific medical costs in older male adults with BPH treated with tamsulosin vs other alpha-1 blockers (i.e., doxazosin, terazosin, and alfuzosin).This was a retrospective propensity-score matched cohort study based on 2006-2012 Medicare claims data. All-cause medical costs and BPH-specific medical costs were compared between tamsulosin and other alpha-1 blockers treatment groups using baseline-adjusted quantile regression analyses. The comparisons were performed at different percentiles of the cost distributions.176,793 older male adults with BPH who used alpha-1 blockers were included in the analysis. All-cause medical costs in 75th and 95th percentiles of the cost distribution are substantially higher in tamsulosin treatment group when compared to other alpha-1 blocker medications (p 0.05 for all). Tamsulosin treatment group had substantially higher BPH-specific medical costs in 99th percentile of the cost distribution when compared to doxazosin and terazosin (p 0.001 for all). Overall, the top 5% of the patients with the highest all-cause medical costs accounted for approximately 45% of the overall all-cause medical costs, and the top 1% of the patients with the highest BPH-specific medical costs accounted for 39-51% of those costs.Older adults with BPH who encountered higher medical expenses had substantially higher medical costs when treated with tamsulosin than other common alpha blockers. Cost-related quality of measures should be assessed to improve health outcomes in older adults with BPH.

Historically, Blacks and Hispanics have had lower opioid-involved overdose death rates in Connecticut (CT). We examined if a shift has taken place where rates of Black fatal overdoses have now surpassed Whites in the state. Drug overdose fatality rates were calculated by number of deaths per year per 100,000 population from 2012 to 2019 in Connecticut. Measures were by race (White, Hispanic, Black, and Asian or Pacific Islander), age groups, and types of drugs, including fentanyl, heroin, cocaine, and other opioids. Poisson regression was used to test the interactions (race × age); joinpoint regression analysis was used to evaluate trend lines of fatality rate by racial/ethnic group within each age group with a significance level of p < 0.05. Drug overdose fatality rates in CT from 2012 to 2019 showed a significant increase for all races combined, estimated 3.6 deaths per 100,000 population per year. For Whites, overdose deaths were 4.6 per year from 2012 to 2017 with no change from 2017 to 2019. The overdose fatality rate for Hispanics was 3.0 and for Asian or Pacific Islanders 0.6 per year from 2012 to 2019. For Blacks, the death rates were statistically flat between 2012 and 2014; however, from 2015 to 2019, this group saw the largest average increase of 6.0 overdose deaths per 100,000 population each year. By 2019, the overdose fatality rate was higher in Blacks than in Whites, (39 vs. 38 per 100,000, respectively). Further, Blacks ages 50 years and over reported the highest overdose fatality rates among all race/age groups, an increase of 8.5 deaths per 100,000 population since 2014. Connecticut is a microcosm of the opioid overdose trend in the New England region of our country. The majority of overdose deaths in CT involved illicit drugs, fentanyl, heroin, and cocaine, rather than prescription drugs. Blacks 50-years-old and over showed the fastest growing overdose death rates. Opioid deaths are now shifting to the Black community, creating an urgent public health crisis.

The enhancement of flow induced vibration of a circular cylinder by a rotating control rod is investigated through two-dimensional numerical simulations. The Reynolds number, diameter ratio, and gap ratio are 150, 0.2, and 0.2, respectively. Simulations are conducted for two rod position angles of β = 90° and 135°, rotation rates ranging from 0 to 6, and reduced velocities ranging between 1 and 20. The response of the cylinder–rod system at the rotation rates 0 and 1 has a lock-in regime where the vibration amplitude is high and the vibration frequency stops increasing with the increase in reduced velocity linearly. For rotation rates exceeding 2, the response amplitude increases with the increase in reduced velocity and enters the lock-in regime at the lower boundary reduced velocity. It remains high until the largest studied reduced velocity of 20; as a result, the higher boundary reduced velocity of the lock-in regime cannot be determined. The vibration with large amplitudes and large rotation rates repeats cyclically after every two or more vibration periods. As a result, two combined wake modes are found: 2S/P + S and 2P/P + S. In a combined mode, the vibration changes from one mode to another within each cycle. The cylinder receives power from the fluid, and the rotating rod gives power to the fluid although the net power exchange between the whole system and the fluid is zero.

Semaphorin 3A (Sema3A) is an axonal guidance molecule that inhibits angiogenesis by vasorepulsion and blocks revascularization in the ischemic retina. BI-X is an intravitreal anti-Sema3A agent under clinical investigation in patients with proliferative diabetic retinopathy (PDR) and diabetic macular ischemia (DMI).Surface plasmon resonance was used to determine binding affinity of BI-X to human and murine Sema3A. In vitro, human retinal microvascular endothelial cells (HRMECs) were used to assess effects of BI-X on cell permeability and cytoskeletal collapse induced by Sema3A. In vivo, intravitreal BI-X or an anti-trinitrophenol control antibody was administered in both eyes in mice with oxygen-induced retinopathy (OIR). Retinal flat mounts were prepared, and avascular area and tip cell density were determined using confocal laser-scanning microscopy.Dissociation constants for BI-X binding to human and murine Sema3A were 29 pM and 27 pM, respectively. In vitro, BI-X prevented HRMEC permeability and cytoskeletal collapse induced by Sema3A. In vivo, BI-X increased tip cell density by 33% (P0.001) and reduced avascular area by 12% (not significant). A significant negative correlation was evident between avascular area and tip cell density (r2 = 0.4205, P0.0001).BI-X binds to human Sema3A with picomolar affinity and prevents cell permeability and cytoskeletal collapse in HRMECs. BI-X also enhances revascularization in mice with OIR.BI-X is a potent inhibitor of human Sema3A that improves revascularization in a murine model of OIR; BI-X is currently being investigated in patients with laser-treated PDR and DMI.

To document changes of stress and illicit drug use among women from 4 months prepregnancy to 6 months postpartum. In a longitudinal study of drug use in family planning clinics, 121 women who became pregnant were matched with 202 women who did not become pregnant. Self-reported drug use, Cohen’s Perceived Stress Scale, and open-ended stress questions were examined every 2 months during the study period of time. Among drug-using pregnant women, drug use declined during 2nd and 3rd trimesters and increased immediately within 1 to 2 months postpartum. Levels of perceived stress declined throughout pregnancy up to 2 months postpartum, increased at 3 to 4 months postpartum and then declined at 6 months postpartum. In contrast, among nondrug-using pregnant women, stress remained stable until the 2nd trimester, increased from 3rd trimester to 1–2 months postpartum, then declined continuously to 6 months postpartum. For non-pregnant women, at the matched timeline, there was no clear pattern for changes of drug use and stress. Our study has illustrated a complex time course of changes of both perceived stress and drug use from prepregnancy through 6 months postpartum. For drug-using pregnant women, pregnancy showed protective effect in reduction of both drug use and stress during pregnancy; and during postpartum, drug resumption peaked at 1–2 months while stress peaked at 3–4 months. If we can identify modifiable, pregnancy-related resiliency factors for both stress and drug use, we can begin to extend prevention efforts initiated during pregnancy into the postpartum period.

The main aim of this paper is to analyze the effects of the heave motion of an elastically supported floating oscillating water column device (OWC) on wave energy harvesting efficiency through two-dimensional computational fluid dynamics simulations. After the numerical model is validated using experimental data, it is used to analyze the effect of the natural frequency ratio on the hydrodynamic efficiency of the OWC. The natural frequency ratio is the ratio of the natural frequency to the wave frequency. The numerical results prove that the natural frequency ratio must be greater than 3 for achieving the best hydrodynamic efficiency. The best hydrodynamic efficiency decreases with the decrease in the natural frequency ratio when the latter is 3. If the natural frequency ratio is smaller than 3, both the amplitudes of wave surface elevation and the displacement of the OWC chamber increase but the harvested energy reduces because the relative motion of the wave surface and the OWC device is small. The energy dissipation due to vortices does not have a strong contribution to the reduction of energy at small natural frequencies.

Background There are few studies focusing on pediatric teledermatology, and the impact of a large-scale pediatric teledermatology program on the accessibility and efficiency of dermatology care remains unclear. This study evaluated the impact of a state-wide implementation of a store-and-forward teledermatology program augmented by the incorporation of dermoscopy in pediatric patients visiting community health centers. Methods It was a descriptive, retrospective cohort study of 876 pediatric dermatology referrals. Results In the traditional referral system, only 60 patients (17.6%) were seen by dermatologists with average waiting times of 75 days due to limited access. In comparison, with an implementation of dermoscopy-aided teledermatology, all 536 teledermatology referrals received dermatological care within 24 h, of which only 64 (12%) patients requires face-to-face (F2F) consultation. Patients referred for F2F consultation via eConsults had a much lower no-show rate as compared to the traditional referral system (39% vs. 71%). Side by side comparison between general population and pediatric population has demonstrated shared features in efficiency and access improvement but revealed specific characteristics of pediatric teledermatology in terms of diagnosis and treatment. Conclusion Coordinated store-and-forward teledermatology platform with incorporation of dermoscopy between large community care network and dermatology provider can greatly improve access to pediatric dermatology care especially in underserved population. The efficiency of teledermatology in access improvement for pediatric population is comparable with adult population in eConsults. There are also unique features and challenges in pediatric teledermatology that require further research.

Research continues to highlight the central relationship between caregivers’ mental health and their children’s development. This study examined the relation between primary caregivers’ mental health and school-aged children’s outcomes, including student mental health, resilience, and academic performance, in rural China. Using cross-sectional data from economically poor areas in the Gansu province, 2989 students (mean age = 11.51, 53.33% male, 46.67% female) and their primary caregivers (74.2% female) completed the 21-item, self-report Depression Anxiety Stress Scale. Students also completed the 25-item Connor-Davidson Resilience Scale and a standardized math test. The results indicated a high prevalence of caregiver depression (31%), stress (39%), and anxiety (24%). Characteristics that were significantly correlated with caregiver mental health issues included being a grandparent, having a low socioeconomic status and low education level, and living in a household with at least one migrant worker. Apart from caregiver stress and student resilience, caregiver mental health issues were negatively correlated with all student outcomes, including student mental health, resilience, and academic performance. Although additional empirical research is needed to investigate the associations between caregiver mental health and student outcomes, our results suggest that rural communities could benefit greatly from programs focused on improving the mental health of caregivers and this, in turn, may have a positive impact on student outcomes.

Background Juxta-papillary duodenal diverticulum (JPDD) has been associated with obstructive jaundice and ascending cholangitis. Potential mechanisms include periampullary colonization of pathogenic bacteria and mechanical obstruction. However, the relation of JPDD with pyogenic liver abscess (PLA) has not been reported. Moreover, approximately one third of patients with PLA have no identifiable risk factors and are labelled as “cryptogenic”. We hypothesized that JPDD is an unidentified risk factor for cryptogenic PLA and the aim of this study was to examine this association. Methods We conducted a retrospective chart review to identify cases of PLA (n = 66) and compare those to matched controls (n = 66). 66 patients met the study inclusion criteria of a diagnosis of PLA using computerized tomography (CT) imaging and either positive culture or confirmed resolution after antibiotic therapy. Patients with diagnoses of amebic liver abscess, traumatic liver abscess, post cholecystectomy liver abscess, concurrent acute cholecystitis, and hepatobiliary malignancy were excluded. Controls were identified from a radiology database and matched one-to-one with the cases by age and sex. Demographic and clinical data was extracted from electronic medical records. CT scan images of all cases and controls were reviewed by a single expert radiologist to identify the presence of JPDD. Statistical tests including Chi-square and t-test with multiple logistic regression were used to examine the group differences in JPDD and other factors. Results Among 132 study samples, 13.6% (9/66) of the cases were found to have JPDD, compared to 3.0% (2/66) among controls (p = 0.03). This corresponded to an odds ratio (OR) of 5.05 [OR 5.05; CI 1.05–24.4] on multiple logistic regression analysis. In addition, 1/3rd of PLA cases with JPDD had no other traditional risk factors (cryptogenic PLA). However, a statistically significant association of JPDD with cryptogenic PLA could not be established possibly because of a small number of cases. We found significantly high rate of diabetes mellitus (DM) (42.4%; n = 28/66) among cases compared to controls (21.2%; n = 14/66; p = 0.01). Conclusion We found a significant association between JPDD and PLA. We need studies with larger sample sizes to confirm this relationship and to explore if JPDD could be related to cryptogenic liver abscesses.

Flow around a high-speed rotating circular cylinder for $Re\leqslant 500$ is investigated numerically. The Reynolds number is defined as $UD/\unicode[STIX]{x1D708}$ with $U$, $D$ and $\unicode[STIX]{x1D708}$ being the free-stream flow velocity, the diameter of the cylinder and the kinematic viscosity of the fluid, respectively. The aim of this study is to investigate the effect of a high rotation rate on the wake flow for a range of Reynolds numbers. Simulations are performed for Reynolds numbers of 100, 150, 200, 250 and 500 and a wide range of rotation rates from 1.6 to 6 with an increment of 0.2. Rotation rate is the ratio of the rotational speed of the cylinder surface to the incoming fluid velocity. A systematic study is performed to investigate the effect of rotation rate on the flow transition to different flow regimes. It is found that there is a transition from a two-dimensional vortex shedding mode to no vortex shedding mode when the rotation rate is increased beyond a critical value for Reynolds numbers between 100 and 200. Further increase in rotation rate results in a transition to three-dimensional flow which is characterized by the presence of finger-shaped (FV) vortices that elongate in the wake of the cylinder and very weak ring-shaped vortices (RV) that wrap the surface of the cylinder. The no vortex shedding mode is not observed at Reynolds numbers greater than or equal to 250 since the flow remains three-dimensional. As the rotation rate is increased further, the occurrence frequency and size of the ring-shaped vortices increases and the flow is dominated by RVs. The RVs become bigger in size and the flow becomes chaotic with increasing rotation rate. A detailed analysis of the flow structures shows that the vortices always exist in pairs and the strength of separated shear layers increases with the increase of rotation rate. A map of flow regimes on a plane of Reynolds number and rotation rate is presented.

Objective The aim of this study is to examine the effectiveness of a single physician-led weight loss program in a primary care. Methods This is a retrospective analysis of 300 patients with a BMI >30 kg/m2 in an outpatient weight loss program. Weight loss interventions included lifestyle counseling and pharmacotherapy. Outcomes were assessed based on percentage weight change during a time period of two consecutive visits less than 90 days. Results We found that 57.7%, 43.3% and 16.1% patients who attended the clinic 5 or more times, 4-5 times, 2-3 times respectively achieved 5% weight loss (p < 0.0001). In regard to achieving 10% weight loss, 42.3%, 8.7% and 4.3% patients who attended the clinic 5 or more times, 4-5 times and 2-3 times did it respectively (p

Many vaccine rationing guidelines urge planners to recognize, and ideally reduce, inequities. In the United States, allocation frameworks are determined by each of the Centers for Disease Control and Prevention's 64 jurisdictions (50 states, the District of Columbia, five cities and eight territories). In this study, we analyzed vaccine allocation plans published by 8 November 2020, tracking updates through to 30 March 2021. We evaluated whether jurisdictions adopted proposals to reduce inequity using disadvantage indices and related place-based measures. By 30 March 2021, 14 jurisdictions had prioritized specific zip codes in combination with metrics such as COVID-19 incidence, and 37 jurisdictions (including 34 states) had adopted disadvantage indices, compared to 19 jurisdictions in November 2020. Uptake of indices doubled from 7 to 14 among the jurisdictions with the largest shares of disadvantaged communities. Five applications were distinguished: (1) prioritizing disadvantaged groups through increased shares of vaccines or vaccination appointments; (2) defining priority groups or areas; (3) tailoring outreach and communication; (4) planning the location of dispensing sites; and (5) monitoring receipt. To ensure that equity features centrally in allocation plans, policymakers at the federal, state and local levels should universalize the uptake of disadvantage indices and related place-based measures.

The main challenge to develop HCF for IgG and Ig-based therapeutics is to achieve essential solubility, viscosity and stability of these molecules in order to maintain product quality and meet regulatory requirement during manufacturing, production, storage, shipment and administration processes. The commonly used and FDA approved excipients for IgG and Ig -based therapeutics may no longer fulfil the challenge of HCF development for these molecules to certain extent, especially for some complex Ig-based platforms. 2-Hydroxypropyl beta-cyclodextrin (HP-β-CD) is one of the promising excipients applied recently for HCF development of IgG and Ig-based therapeutics although it has been used for formulation of small synthesized chemical drugs for more than thirty years. This review describes essential aspects about application of HP-β-CD as excipient in pharmaceutical formulation, including physico-chemical properties of HP-β-CD, supply chain, regulatory, patent landscape, marketed drugs with HP-β-CD, analytics and analytical challenges, stability and control strategies, and safety concerns. It also provides an overview of different studies, and outcomes thereof, regarding formulation development for IgGs and Ig-based molecules in liquid and solid (lyophilized) dosage forms with HP-β-CD. The review specifically highlights the challenges for formulation manufacturing of IgG and Ig-based therapeutics with HP-β-CD and identifies areas for future work in pharmaceutical and formulation development.

Many fatigue crack models in literature neglect the effects of dynamic loads such as mass unbalance. A breathing model that includes the effects of unbalance angle and eccentricity on the breathing mechanism of a fatigue crack is proposed. When the proposed model was used to simulate the vibration of a cracked rotor, it was revealed that 120–180° placement of the unbalanced mass relative to the crack direction resulted in critical speed and peak amplitude values similar to an undamaged shaft. Also, 180° placement of the unbalanced mass resulted in the diminishing of 2× and 3× frequency amplitudes for a poorly balanced rotor. However, a decently balanced rotor still revealed an appreciable 2× frequency amplitude despite 180° placement of the unbalance mass. These findings suggest that unbalance angle placement can only shroud the presence of cracks in poorly balanced rotors, therefore highlighting the importance of controlling the unbalance angle and magnitude to ensure the greatest detection of fatigue cracks.

Continuous welded rails (CWRs) have significantly strengthened the railway tracks by eliminating rail joints between rails. However, as the ambient temperature changes during a year from cold winter to extremely hot summer, high thermal stresses exist and change within the CWR. In some circumstances, it may cause catastrophic disasters such as track buckling, broken rails, and/or derailment. To ensure the CWR track is in stable, longitudinal stress (neutral temperature of CWR) measurement is the most important of the CWR track maintenance. Using the non-destructive method to measure the longitudinal thermal stress in CWR tracks is one of the effort directions for railway track engineers and researches for decades. Within Australia, in the last decade, three types of non-destructive technologies have been approved by the railway infrastructure authorities for neutral temperature measurement. In this paper, the physical theories and technical background of these three technologies are introduced and discussed. In addition, the advantages and limitations of these technologies are discussed based on the experiences that are obtained by using them.