The energy-harvesting performance of two oscillating hydrofoil turbines in tandem configuration is experimentally studied at a $Re$ of $20\,000$ to determine the array’s optimal kinematics. By characterising interactions between the leading foil’s wake and the trailing foil, the kinematic configuration required to maximise array power extraction is identified. This is done by prescribing leading-foil kinematics that produce specific wake regimes, identified by the maximum effective angle of attack, $\alpha _{T/4}$, parameter. The kinematics of the trailing foil are varied significantly from those of the leading foil, with heave and pitch amplitudes of $0.6c\lt h_{0,{\textit{tr}}}\lt 1.8c$ and $65^{\circ} \lt \theta _{0,{\textit{tr}}}\lt 75^{\circ}$, and inter-foil phase of $-110^{\circ} \lt \psi _{1-2}\lt 180^{\circ}$. Configurations with reduced frequencies of $0.11$ and $0.12$, and foil separations of $4c$ and $6c$ are tested within each wake regime. The power extracted by each foil over an oscillation cycle is measured through force and torque measurements. Wake–foil interactions that improve trailing foil performance are analysed with time-resolved particle image velocimetry. Constructive and destructive wake–foil interactions are compared, showing that trailing-foil performance improves by either avoiding wake vortices or interacting directly with them. By interacting with the primary wake vortex, the latter configuration sees no power loss during the cycle. System power from the two foils is found to be maximised when the leading foil operates at an intermediate $\alpha _{T/4}$ range, and when the trailing foil avoids wake vortices. This optimal array configuration sees both foils operating with different kinematics compared with the optimal kinematics of a single oscillating foil.

Childhood obesity persists at historically high rates globally, including an increasing number of children with severe obesity(1–3). Despite the growing demand of families with children needing treatment, effective interventions are largely unavailable or inaccessible(4,5). Using technology to transform such services that are conventionally delivered in person and offering electronic health (e-Health) interventions, may address limitations of current childhood obesity treatment. A randomised control trial (RCT) with a waitlisted control group evaluated the effectiveness of a 10-week family-focused web-based healthy lifestyle program with health coaching sessions, for treating childhood overweight and obesity, over 10 weeks. Outcome measures included change in children’s body mass index (BMI) z-score, waist circumference, dietary intake, physical activity, and quality of life, collected online at baseline and end of the web-based program (10 weeks). A total of 148 children (125 families) aged 7–13 years, with BMI ≥ 85th percentile, living in Victoria, Australia, were recruited and randomised to intervention (Cohort 1) or waitlist control (Cohort 2), of which 102 children (85 families) completed the RCT. Cohort 2 received no intervention during the control period. A clinically meaningful decrease in BMI z-score, in the context of weight maintenance and height growth, was observed in Cohort 1 compared to a negligible change found in Cohort 2 (mean difference in change in BMI z-score Cohort 1 vs Cohort 2 = −0.1; 95% confidence interval, −0.2, –0.0). Compared with Cohort 2, Cohort 1 adopted health-supporting lifestyle behaviours, such as improved diet quality and increased physical activity; and reported a clinically significant improvement in children’s quality of life at 10 weeks. Cohort 2 demonstrated similar changes in outcome measures after receiving the web-based program. Findings from this study furthers the growing body of evidence on the potential of e-Health interventions to upscale childhood obesity treatment. E-Health interventions, including a low-intensity program that requires minimal contact time with health professionals online, can enhance the effectiveness of conventional treatment services.

Objectives/Goals: Mathematical models of airborne virus transmission lack supporting field and clinical data such as viral aerosol emission rates and airborne infectious doses. Here, we aim to measure inhalation exposure to influenza aerosols in a room shared with persons with community-acquired influenza and estimate the infectious dose via inhalation. Methods/Study Population: We recruited healthy volunteer recipients and influenza donors with polymerase chain reaction (PCR)-confirmed community-acquired infection. On admission to a hotel quarantine, recipients provided sera to determine baseline immunity to influenza virus, and donor infections were confirmed by quantitative real-time polymerase chain reaction. Donors and recipients were housed in separate rooms and interacted in an “event room” with controlled ventilation (0.2 – 0.5 air changes/hour) and relative humidity (20–40%). We collected ambient bioaerosol exposure samples using NIOSH BC-251 samplers. Donors provided exhaled breath samples collected by a Gesundheit-II (G-II). We analyzed aerosol samples using dPCR and fluorescent focus assays for influenza A and sera by hemagglutinin inhibition assay (HAI) against donor viruses and vaccine strains. Results/Anticipated Results: Among two cohorts (24b and 24c), we exposed 11 recipients (mean age: 36; 55% female) to 5 donors (mean age: 21; 80% female) infected with influenza A H1N1 or H3N2. Eight G-II and two NIOSH bioaerosol samples (1–4 µm and ≥4 µm) were PCR positive. We cultured virus from one G-II sample. Based on previous literature, we hypothesized that ~50% of immunologically naïve people (HAI Discussion/Significance of Impact: We demonstrated that it is feasible to recruit donors with community-acquired influenza and expose recipients to measurable virus quantities under controlled conditions. However, baseline immunity was high among volunteers. Our work sets the stage for designing studies with increased sample sizes comprising immunologically naïve volunteers.

Objectives/Goals: We describe the prevalence of individuals with household exposure to SARS-CoV-2, who subsequently report symptoms consistent with COVID-19, while having PCR results persistently negative for SARS-CoV-2 (S[+]/P[-]). We assess whether paired serology can assist in identifying the true infection status of such individuals. Methods/Study Population: In a multicenter household transmission study, index patients with SARS-CoV-2 were identified and enrolled together with their household contacts within 1 week of index’s illness onset. For 10 consecutive days, enrolled individuals provided daily symptom diaries and nasal specimens for polymerase chain reaction (PCR). Contacts were categorized into 4 groups based on presence of symptoms (S[+/-]) and PCR positivity (P[+/-]). Acute and convalescent blood specimens from these individuals (30 days apart) were subjected to quantitative serologic analysis for SARS-CoV-2 anti-nucleocapsid, spike, and receptor-binding domain antibodies. The antibody change in S[+]/P[-] individuals was assessed by thresholds derived from receiver operating characteristic (ROC) analysis of S[+]/P[+] (infected) versusS[-]/P[-] (uninfected). Results/Anticipated Results: Among 1,433 contacts, 67% had ≥1 SARS-CoV-2 PCR[+] result, while 33% remained PCR[-]. Among the latter, 55% (n = 263) reported symptoms for at least 1 day, most commonly congestion (63%), fatigue (63%), headache (62%), cough (59%), and sore throat (50%). A history of both previous infection and vaccination was present in 37% of S[+]/P[-] individuals, 38% of S[-]/P[-], and 21% of S[+]/P[+] (P<0.05). Vaccination alone was present in 37%, 41%, and 52%, respectively. ROC analyses of paired serologic testing of S[+]/P[+] (n = 354) vs. S[-]/P[-] (n = 103) individuals found anti-nucleocapsid data had the highest area under the curve (0.87). Based on the 30-day antibody change, 6.9% of S[+]/P[-] individuals demonstrated an increased convalescent antibody signal, although a similar seroresponse in 7.8% of the S[-]/P[-] group was observed. Discussion/Significance of Impact: Reporting respiratory symptoms was common among household contacts with persistent PCR[-] results. Paired serology analyses found similar seroresponses between S[+]/P[-] and S[-]/P[-] individuals. The symptomatic-but-PCR-negative phenomenon, while frequent, is unlikely attributable to true SARS-CoV-2 infections that go missed by PCR.

We use the 529 college savings plan setting to investigate whether and why households make suboptimal choices to invest in local assets. We estimate that 67% of open accounts between 2010 and 2020 were located suboptimally due to the plans’ tax inefficiencies and high expenses. Over the accounts’ projected lifetimes, such investments yielded expected losses of 8% on average or $15.6 billion in 2020 alone. We then investigate why suboptimal investment is so prevalent. Consistent with households’ lack of understanding of state-level tax benefits, we find that a meaningful proportion of households does not account for the potential tax benefits and costs of local versus nonlocal 529 investment. Household financial literacy and plan disclosure complexity appear to explain suboptimal investment patterns, which further supports the role of information-processing frictions. Our study presents novel evidence on individuals’ preferences for local assets and how information-processing frictions shape their investment decisions, reducing their financial well-being.

This study conducts experimental investigations into wake-induced vibration (WIV) of a circular cylinder placed downstream of an oscillating cylinder. Surprisingly, it is observed that the previously identified WIV phenomenon, characterized by a sustained increase in amplitude at higher reduced velocities, does not occur when the upstream cylinder oscillates at large amplitudes. Instead, a different phenomenon, which we refer to as the ‘wake-captured vibration’, becomes dominant. The experiments reveal a negative correlation between the vortex-induced vibration amplitude response of the upstream cylinder and the WIV amplitude response of the downstream cylinder. Through a quasi-steady and linear instability analysis, the study demonstrates that the previously proposed wake-displacement mechanism may not be applicable for predicting the cylinder WIV response in the wake of an oscillating body. This is because the lift force gradients across the wake, measured through stationary cylinder experiments, decrease significantly when the upstream cylinder vibrates at higher amplitudes. Consequently, actively controlled vibration experiments are conducted to systematically map the hydrodynamic properties of the downstream cylinder vibrating in the wake of an oscillating cylinder. The findings align with observations from free-vibration experiments, and help to explain the amplitude and frequency response of WIV. Additionally, wake visualization through particle image velocimetry is conducted to provide further insights into the complex wake and vortex–body interactions.

Neglect remains understudied compared to other forms of maltreatment. While studies have shown that neglect has negative effects on mental health in adolescence, yet unresolved is whether these impacts result from critical period or cumulative effects. In the present article, we use a novel approach to compare these two hypotheses from the impact of two types of neglect, failure to provide (FTP) and lack of supervision (LOS), on adolescent depression and internalizing symptoms. Data derive from the LONGSCAN consortium, a diverse, multi-site, prospective study of children from approximately age 2–16. Despite our hypothesis that the critical period of early childhood would have the greatest impact on adolescent internalizing mental health, exposure to neglect during the critical period of adolescence (ages 12–16) was the best-fitting model for the effects of FTP neglect on depression, and the effects of LOS neglect on both depression and internalizing symptoms. The cumulative model (exposure across all time periods) best explained the effects of FTP neglect on internalizing symptoms. Results were robust to the addition of control variables, including other forms of maltreatment. These findings demonstrate that responding to neglect into adolescence must be considered as urgent for child welfare systems.

The effect of treatment with praziquantel (PZQ) on the tegument of adult Schistosoma mansoni worms and on liver egg-granulomas has been examined in mice infected with PZQ-resistant and -susceptible parasite isolates. Two PZQ-resistant S. mansoni isolates, one selected by passage in the laboratory under drug pressure and one from Senegal established from eggs excreted by an uncured patient, were compared with PZQ-susceptible control isolates. Scanning electron microscopic observations on the tegument of Schistosoma adult worms treated in vivo with PZQ showed that more severe damage was inflicted by PZQ on susceptible worms than on drug-resistant worms. Observations on the pathology of Schistosoma egg-granulomas in the liver of infected mice after treatment with PZQ indicated that eggs from susceptible control isolates were more sensitive to PZQ than those from drug-resistant isolates.

Research experience is often important for academic and career development. This paper describes the implementation and impact of a training program for temporary research assistants (RAs) at an academic medical center. The program includes a 9-month didactic lecture series covering research and professional development skills, a Quality Improvement project focused on improving research processes, and manuscript writing. Overall, the program goals of increasing confidence, self-efficacy, job satisfaction, and well-being, as well as providing an opportunity for career exploration, were met. Thus, this program has the potential to support temporary RAs and enhance their early research experiences.

We present the third data release from the Parkes Pulsar Timing Array (PPTA) project. The release contains observations of 32 pulsars obtained using the 64-m Parkes ‘Murriyang’ radio telescope. The data span is up to 18 yr with a typical cadence of 3 weeks. This data release is formed by combining an updated version of our second data release with $\sim$3 yr of more recent data primarily obtained using an ultra-wide-bandwidth receiver system that operates between 704 and 4032 MHz. We provide calibrated pulse profiles, flux density dynamic spectra, pulse times of arrival, and initial pulsar timing models. We describe methods for processing such wide-bandwidth observations and compare this data release with our previous release.

The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.

To enhance the performance of anti-ship missiles cooperative attack, this paper proposes a finite-time trajectory shaping-based cooperative guidance law (TSCGL). Firstly, the cooperative guidance model is established on segmented linearisation of the missile’s heading angle. Then, a trajectory shaping guidance law for a single missile is derived by a weighted optimal energy cost function and Schwarz inequality. On this basis, a finite-time TSCGL is proposed combined with trajectory shaping technology and finite-time theory. The desirable finite-time convergence performance can ensure a simultaneous attack. Through an improved method of time-to-go estimation, it is independent of small-angle assumption and relaxes the launching conditions of the missiles. Additionally, the proposed finite-time TSCGL can achieve better damage performance through energy management. Finally, simulation results demonstrate the effectiveness and superiority of the proposed finite-time TSCGL.

As a typical plasma-based optical element that can sustain ultra-high light intensity, plasma density gratings driven by intense laser pulses have been extensively studied for wide applications. Here, we show that the plasma density grating driven by two intersecting driver laser pulses is not only nonuniform in space but also varies over time. Consequently, the probe laser pulse that passes through such a dynamic plasma density grating will be depolarized, that is, its polarization becomes spatially and temporally variable. More importantly, the laser depolarization may spontaneously take place for crossed laser beams if their polarization angles are arranged properly. The laser depolarization by a dynamic plasma density grating may find application in mitigating parametric instabilities in laser-driven inertial confinement fusion.

This study sought to investigate Chinese farmers’ attitude towards animal welfare by using the Theory of Planned Behaviour (TPB). According to the TPB, an individual's intention to behave in a certain way is determined by his/her attitude towards the behaviour (specific attitude — importance — and general attitudes), the perceived behavioural control (easiness), and the supposed opinion of the people who are important to him/her (subjective norms). A total of 253 questionnaires were used, which included the three main animal productions in China (swine, poultry and cattle). Chinese farmers have perceived the improvement of animal welfare as two abstracts: general attitudes (reward-seeking, and empathic farmer); and four specific categories of actions (favourable environment, animal health, humane treatment of animals and farmers’ well-being). Our analysis revealed that general and specific attitudes were the strongest predictors of farmers’ intentions to improve animal welfare in the questionnaire study. In fact, Chinese farmers considered it fairly important to improve the animal welfare measures considered in the survey. In contrast, the same animal welfare measures were considered difficult to improve by the farmers as indicated by the lack of association between the easiness of improving animal welfare and the intentions. In addition, veterinarians, agricultural advisers, and scientific experts were considered to be relatively influential subjective norms as regards the activities of the farmers. This is the first study to provide an insight into the underlying meanings and values of Chinese farmers’ views on improvements to animal welfare.

Background: The coronavirus disease 2019 (COVID-19) pandemic has led the implementation of institutional infection control protocols. This study will determine the effects of these protocols on outcomes of acute ischemic stroke (AIS) patients treated with endovascular therapy (EVT). Methods: Uninterrupted time series analysis of the impact of COVID-19 safety protocols on AIS patients undergoing EVT. We analyze data from prospectively collected quality improvement databases at 6 centers from March 11, 2019 to March 10, 2021. The primary outcome is 90-day modified Rankin Score (mRS). The secondary outcomes are angiographic time metrics. Results: Preliminary analysis of one stroke center included 214 EVT patients (n=150 pre-pandemic). Baseline characteristics were comparable between the two periods. Time metrics “last seen normal to puncture” (305.7 vs 407.2 min; p=0.05) and “hospital arrival to puncture” (80.4 vs 121.2 min; p=0.04) were significantly longer during pandemic compared to pre-pandemic. We found no significant difference in 90-day mRS (2.0 vs 2.2; p=0.506) or successful EVT rate (89.6% vs 90%; p=0.93). Conclusions: Our results indicate an increase in key time metrics of EVT in AIS during pandemic, likely related to infection control measures. Despite the delays, we found no difference in clinical outcomes between the two periods.

Sustainability encompasses social, economic and environmental issues with the primary aim to fulfil the needs of the present society without compromising the potential needs of future generations. Product design has been identified to greatly influence the sustainability of New Product Development. This study aims to identify and review the fundamental factors in which product design has the ability to influence and improve the overall environmental sustainability of a product. A comprehensive literature review has been performed to establish trends over the past four decades. The factors that have significant potential, such as the 6Rs, waste and energy, which aid designers in the implementation of environmental sustainability during the product design process have been identified and discussed. Through this analysis, a new conceptual framework has been conceived, facilitating designers in implementing environmental sustainability during product development. In addition, future research opportunities have been identified.