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This research builds on the work of D.K. Gode and Shyam Sunder who demonstrated the existence of a strong relationship between market institutions and the ability of markets to seek equilibrium—even when the agents themselves have limited intelligence and behave with substantial randomness. The question posed is whether or not market institutions account for the operation of the law of supply and demand in markets populated by humans with no role required of human rationality. Are institutions responsible for the operations of the law of supply and demand or are behavioral principles also at work? Experiments with humans and simulations with robots both conducted in conditions in which major institutional and structural aids to convergence were removed, produced clear answers. Human markets converge, while robot markets do not. The structural and institutional features certainly facilitate convergence under conditions of substantial irrationality, but they are not necessary for convergence in markets in which agents have the rationality of humans.
Quantum field theory predicts a nonlinear response of the vacuum to strong electromagnetic fields of macroscopic extent. This fundamental tenet has remained experimentally challenging and is yet to be tested in the laboratory. A particularly distinct signature of the resulting optical activity of the quantum vacuum is vacuum birefringence. This offers an excellent opportunity for a precision test of nonlinear quantum electrodynamics in an uncharted parameter regime. Recently, the operation of the high-intensity Relativistic Laser at the X-ray Free Electron Laser provided by the Helmholtz International Beamline for Extreme Fields has been inaugurated at the High Energy Density scientific instrument of the European X-ray Free Electron Laser. We make the case that this worldwide unique combination of an X-ray free-electron laser and an ultra-intense near-infrared laser together with recent advances in high-precision X-ray polarimetry, refinements of prospective discovery scenarios and progress in their accurate theoretical modelling have set the stage for performing an actual discovery experiment of quantum vacuum nonlinearity.
In recent years, the rapid convergence of artificial intelligence (AI) and low-altitude flight technology has driven significant transformations across various industries. These advancements have showcased immense potential in areas such as logistics distribution, urban air mobility (UAM) and national defense. By adopting the AI technology, low-altitude flight technology can achieve high levels of automation and operate in coordinated swarms, thereby enhancing efficiency and precision. However, as these technologies become more pervasive, they also raise pressing ethical or moral concerns, particularly regarding privacy, public safety, as well as the risks of militarisation and weaponisation. These issues have sparked extensive debates. In summary, while the integration of AI and low-altitude flight presents revolutionary opportunities, it also introduces complex ethical challenges. This article will explore these opportunities and challenges in depth, focusing on areas such as privacy protection, public safety, military applications and legal regulation, and will propose strategies to ensure that technological advancements remain aligned with ethical or moral principles.
Echocardiographic Z-score models play a crucial role in defining cardiac pathology in paediatric patients. There are multiple models that practitioners utilize in the United States without guiding principles to standardize their use. Discrepant interpretations can occur depending on the model chosen, even if standardized Z-score cutoffs are applied. In this study, a survey was developed to assess pediatric cardiologists’ use of Z-score systems when evaluating and treating patients with isolated bicuspid aortic valve. The majority of respondents reported using Z-score cutoffs to evaluate the degree of aortic root and ascending aorta dilation. For the aortic root, mild, moderate, and severe dilation averaged at 2.13 (SD = 0.32), 3.59 (SD = 0.49), and 5.11 (SD = 0.84), respectively. Similar cutoffs were reported for determining ascending aorta dilation. A large proportion of respondents primarily used the Boston system (36%, 18/50) or Boston and Pediatric Heart Network systems together (36%, 18/50). There were also differences in management decisions, such as implementing competitive sports restrictions, based on Z-scores and the 2015 Task Force 7 Bethesda exercise guidelines. These survey results demonstrate variability that exists among paediatric cardiologists in their use of Z-scores for describing aortic root and ascending aorta dilation in patients with isolated bicuspid aortic valve and suggests the need for implementation of national guidelines for Z-score usage.
To compare characteristics between stroke populations with and without sensorineural hearing loss (SNHL) and assess the impact of SNHL on stroke outcome.
Methods
A retrospective study of patients admitted with stroke was carried out. Patients were divided into two groups, where group A were diagnosed with SNHL and group B were without SNHL. Baseline age, gender, vascular risk factors and disability were compared. Logistic regression analyses were performed with three-month mortality and SNHL as dependent variables.
Results
A total of 631 admissions were reviewed, with mean age 79.2 years, including 305 patients with SNHL and 326 without. More severe disability was more prevalent in patients with SNHL. Sensorineural hearing loss was not associated with increased mortality (odds ratio = 1.1, 95 per cent confidence interval = 0.7–2.0, p = 0.668). Hypertension was present in 210 (68.9 per cent) with SNHL versus 189 (58 per cent) without SNHL (p = 0.005). Small-vessel disease aetiology was more prevalent in SNHL 51 (16.7 per cent) versus 30 (9.2 per cent) without SNHL (p = 0.005).
Conclusion
Sensorineural hearing loss appears to have an association with stroke of small-vessel disease aetiology and hypertension. Sensorineural hearing loss does not affect three-month mortality but is associated with increased disability.
Metabolic enzymes are the catalysts that drive the biochemical reactions essential for sustaining life. Many of these enzymes are tightly regulated by feedback mechanisms. To fully understand their roles and modulation, it is crucial to investigate the relationship between their structure, catalytic mechanism, and function. In this perspective, by using three examples from our studies on Mycobacterium tuberculosis (Mtb) isocitrate lyase and related proteins, we highlight how an integrated approach combining structural, activity, and biophysical data provides insights into their biological functions. These examples underscore the importance of employing fast-fail experiments at the early stages of a research project, emphasise the value of complementary techniques in validating findings, and demonstrate how in vitro data combined with chemical, biochemical, and physiological knowledge can lead to a broader understanding of metabolic adaptations in pathogenic bacteria. Finally, we address the unexplored questions in Mtb metabolism and discuss how we expand our approach to include microbiological and bioanalytical techniques to further our understanding. Such an integrated and interdisciplinary strategy has the potential to uncover novel regulatory mechanisms and identify new therapeutic opportunities for the eradication of tuberculosis. The approach can also be broadly applied to investigate other biochemical networks and complex biological systems.
Perioperative anesthesia care for the patients undergoing ophthalmologic procedures is unique and sometimes challenging. Many of the ophthalmologic procedures can often be done with sedation/monitored anesthesia care (MAC) [1]. Intravenous sedatives combined with topical/local/regional anesthesia during eye surgery can alleviate patients’ pain, fear, anxiety, thus improving outcomes [2]. In this chapter we review the current practices and trends in anesthesia service with respect to MAC for ophthalmologic procedures with topical/local/regional anesthesia [1, 2, 3]. The nerve blocks performed for eye surgery determine, to some extent, the techniques and requirement of the sedation level by the anesthesia service. And the traditions of surgery teams and hospitals also affect the choice of sedation technique. The evolvement of surgical techniques seems to facilitate the trend that sedation is more and more used in the eye surgical procedures. Anesthesia care options are also based on surgeons’ skill and anesthesia providers’ comfort level, and the patients’ expectations and demands. Regardless, patients’ safety and perioperative care quality are the key determinants [1, 3, 4].
Transit-time damping (TTD) is a process in which the magnetic mirror force – induced by the parallel gradient of magnetic field strength – interacts with resonant plasma particles in a time-varying magnetic field, leading to the collisionless damping of electromagnetic waves and the resulting energization of those particles through the perpendicular component of the electric field, $E_\perp$. In this study, we utilize the recently developed field–particle correlation technique to analyse gyrokinetic simulation data. This method enables the identification of the velocity-space structure of the TTD energy transfer rate between waves and particles during the damping of plasma turbulence. Our analysis reveals a unique bipolar pattern of energy transfer in the velocity-space characteristic of TTD. By identifying this pattern, we provide clear evidence of TTD's significant role in the damping of strong plasma turbulence. Additionally, we compare the TTD signature with that of Landau damping (LD). Although they both produce a bipolar pattern of phase-space energy density loss and gain about the parallel resonant velocity of the Alfvénic waves, they are mediated by different forces and exhibit different behaviours as the perpendicular velocity $v_\perp \to 0$. We also explore how the dominant damping mechanism varies with ion plasma beta $\beta _i$, showing that TTD dominates over LD for $\beta _i > 1$. This work deepens our understanding of the role of TTD in the damping of weakly collisional plasma turbulence and paves the way to seek the signature of TTD using in situ spacecraft observations of turbulence in space plasmas.
We introduce a low-order dynamical system to describe thermal convection in an annular domain. The model derives systematically from a Fourier–Laurent truncation of the governing Navier–Stokes Boussinesq equations and accounts for spatial dependence of the flow and temperature fields. Comparison with fully resolved direct numerical simulations (DNS) shows that the model captures parameter bifurcations and reversals of the large-scale circulation (LSC), including states of (i) steady circulating flow, (ii) chaotic LSC reversals and (iii) periodic LSC reversals. Casting the system in terms of the fluid's angular momentum and centre of mass (CoM) reveals equivalence to a damped pendulum with forcing that raises the CoM above the fulcrum. This formulation offers a transparent mechanism for LSC reversals, namely the inertial overshoot of a forced pendulum, and it yields an explicit formula for the frequency $f^*$ of regular LSC reversals in the high-Rayleigh-number (Ra) limit. This formula is shown to be in excellent agreement with DNS and produces the scaling law $f^* \sim {Ra}^{0.5}$.
Patients receiving hematopoietic stem cell transplants (HSCT) are at increased risk for Clostridioides difficile infection (CDI). The purpose of this study was to assess the effectiveness of oral vancomycin prophylaxis (OVP) for CDI in HSCT patients.
Design:
Single-center, retrospective cohort.
Setting:
Tertiary care academic medical center in New Jersey.
Patients:
Patients ≥18 years old during admission for the HSCT were included. Patients who were admitted <72 hours or who had an active CDI prior to HSCT day 0 were excluded.
Methods:
Medical records of patients admitted between January 2015 and August 2022 to undergo an allogeneic or autologous HSCT were reviewed. The primary end point was the incidence of in-hospital CDI. Secondary end points included the incidence of vancomycin-resistant enterococci (VRE) bloodstream infections, VRE isolated from any clinical culture, gram-negative bloodstream infections, hospital survival, and hospital length of stay. Exploratory end points, including 1-year survival, relapse, and incidence of graft-versus-host disease, were also collected.
Results:
A total of 156 HSCT patients were included. There was 1 case of CDI (1 of 81, 1.23%) in the OVP group compared to 8 CDI cases (8 of 75, 10.67%) in the no OVP group (P = .0147). There were no significant (P > .05) between-group differences in incidence of gram-negative bloodstream infections, hospital survival, and length of stay. There were zero clinical cultures positive for VRE.
Conclusions:
In-hospital incidence of CDI in HSCT patients was significantly decreased with OVP. Randomized controlled trials are needed in this high-risk population to assess the efficacy and risks of OVP for CDI.
Type 2 diabetes (T2DM) poses a significant public health challenge, with pronounced disparities in control and outcomes. Social determinants of health (SDoH) significantly contribute to these disparities, affecting healthcare access, neighborhood environments, and social context. We discuss the design, development, and use of an innovative web-based application integrating real-world data (electronic health record and geospatial files), to enhance comprehension of the impact of SDoH on T2 DM health disparities.
Methods:
We identified a patient cohort with diabetes from the institutional Diabetes Registry (N = 67,699) within the Duke University Health System. Patient-level information (demographics, comorbidities, service utilization, laboratory results, and medications) was extracted to Tableau. Neighborhood-level socioeconomic status was assessed via the Area Deprivation Index (ADI), and geospatial files incorporated additional data related to points of interest (i.e., parks/green space). Interactive Tableau dashboards were developed to understand risk and contextual factors affecting diabetes management at the individual, group, neighborhood, and population levels.
Results:
The Tableau-powered digital health tool offers dynamic visualizations, identifying T2DM-related disparities. The dashboard allows for the exploration of contextual factors affecting diabetes management (e.g., food insecurity, built environment) and possesses capabilities to generate targeted patient lists for personalized diabetes care planning.
Conclusion:
As part of a broader health equity initiative, this application meets the needs of a diverse range of users. The interactive dashboard, incorporating clinical, sociodemographic, and environmental factors, enhances understanding at various levels and facilitates targeted interventions to address disparities in diabetes care and outcomes. Ultimately, this transformative approach aims to manage SDoH and improve patient care.
Marine litter poses a complex challenge in Indonesia, necessitating a well-informed and coordinated strategy for effective mitigation. This study investigates the seasonality of plastic concentrations around Sulawesi Island in central Indonesia during monsoon-driven wet and dry seasons. By using open data and methodologies including the HYCOM and Parcels models, we simulated the dispersal of plastic waste over 3 months during both the southwest and northeast monsoons. Our research extended beyond data analysis, as we actively engaged with local communities, researchers and policymakers through a range of outreach initiatives, including the development of a web application to visualize model results. Our findings underscore the substantial influence of monsoon-driven currents on surface plastic concentrations, highlighting the seasonal variation in the risk to different regional seas. This study adds to the evidence provided by coarser resolution regional ocean modelling studies, emphasizing that seasonality is a key driver of plastic pollution within the Indonesian archipelago. Inclusive international collaboration and a community-oriented approach were integral to our project, and we recommend that future initiatives similarly engage researchers, local communities and decision-makers in marine litter modelling results. This study aims to support the application of model results in solutions to the marine litter problem.
Ultrafast optical probing is a widely used method of underdense plasma diagnostic. In relativistic plasma, the motion blur limits spatial resolution in the direction of motion. For many high-power lasers the initial pulse duration of 30–50 fs results in a 10–15 μm motion blur, which can be reduced by probe pulse post-compression. Here we used the compression after compressor approach [Phys.-Usp. 62, 1096 (2019); JINST 17 P07035 (2022)], where spectral broadening is performed in thin optical plates and is followed by reflections from negative-dispersion mirrors. Our initially low-intensity probe beam was down-collimated for a more efficient spectral broadening and higher probe-to-self-emission intensity ratio. The setup is compact, fits in a vacuum chamber and can be implemented within a short experimental time slot. We proved that the compressed pulse retained the high quality necessary for plasma probing.
We find that division managers who are connected to the CEO are substantially less likely than others to depart from the firm and are more likely to be promoted. Connected managers are protected when performance is poor, and they display no special ability to improve performance given this protection. Connections matter more in weak governance/incentive environments, and the external labor market and stock market appear skeptical of connected managers’ talents. While much of the evidence suggests inefficient favoritism, connected managers are protected more in peripheral segments, suggesting a possible efficiency benefit in helping to resolve intrafirm information problems.
With the in-depth study of thin-film structures, nonuniform thin films with rigid elements have been applied in the aerospace and flexible electronics industries. For thin-film structures with rigid elements, there is an interaction force between the rigid element and the thin film; therefore, the wrinkling mode of the thin film changes under the influence of the interaction force. In this study, a wrinkle model was developed to predict the wrinkle morphology of thin-film structures with rigid elements on the diagonal. First, the wrinkle patterns of the rigid elements were observed at different positions using tensile experiments. Then, the relationship between the tilt of the rigid element and the wrinkle wavelength was investigated using a finite-element eigenvalue buckling analysis. Finally, local wrinkling caused by the perturbed stress of the rigid element was introduced, and a wrinkling model of a square thin film with rigid elements on the diagonal under tension was established. The theoretical analysis results were compared with simulation and experimental results, demonstrating that the model can accurately describe the wrinkle patterns of thin-film structures containing rigid elements on the diagonal under tension.
From 2020 to December 2022, China implemented strict measures to contain the spread of severe acute respiratory syndrome coronavirus 2. However, despite these efforts, sustained outbreaks of the Omicron variants occurred in 2022. We extracted COVID-19 case numbers from May 2021 to October 2022 to identify outbreaks of the Delta and Omicron variants in all provinces of mainland China. We found that omicron outbreaks were more frequent (4.3 vs. 1.6 outbreaks per month) and longer-lasting (mean duration: 13 vs. 4 weeks per outbreak) than Delta outbreaks, resulting in a total of 865,100 cases, of which 85% were asymptomatic. Despite the average Government Response Index being 12% higher (95% confidence interval (CI): 9%, 15%) in Omicron outbreaks, the average daily effective reproduction number (Rt) was 0.45 higher (95% CI: 0.38, 0.52, p < 0.001) than in Delta outbreaks. Omicron outbreaks were suppressed in 32 days on average (95% CI: 26, 39), which was substantially longer than Delta outbreaks (14 days; 95% CI: 11, 19; p = 0.004). We concluded that control measures effective against Delta could not contain Omicron outbreaks in China. This highlights the need for continuous evaluation of new variants’ epidemiology to inform COVID-19 response decisions.
To examine the effectiveness of Self-Help Plus (SH+) as an intervention for alleviating stress levels and mental health problems among healthcare workers.
Methods
This was a prospective, two-arm, unblinded, parallel-designed randomised controlled trial. Participants were recruited at all levels of medical facilities within all municipal districts of Guangzhou. Eligible participants were adult healthcare workers experiencing psychological stress (10-item Perceived Stress Scale scores of ≥15) but without serious mental health problems or active suicidal ideation. A self-help psychological intervention developed by the World Health Organization in alleviating psychological stress and preventing the development of mental health problems. The primary outcome was psychological stress, assessed at the 3-month follow-up. Secondary outcomes were depression symptoms, anxiety symptoms, insomnia, positive affect (PA) and self-kindness assessed at the 3-month follow-up.
Results
Between November 2021 and April 2022, 270 participants were enrolled and randomly assigned to either SH+ (n = 135) or the control group (n = 135). The SH+ group had significantly lower stress at the 3-month follow-up (b = −1.23, 95% CI = −2.36, −0.10, p = 0.033) compared to the control group. The interaction effect indicated that the intervention effect in reducing stress differed over time (b = −0.89, 95% CI = −1.50, −0.27, p = 0.005). Analysis of the secondary outcomes suggested that SH+ led to statistically significant improvements in most of the secondary outcomes, including depression, insomnia, PA and self-kindness.
Conclusions
This is the first known randomised controlled trial ever conducted to improve stress and mental health problems among healthcare workers experiencing psychological stress in a low-resource setting. SH+ was found to be an effective strategy for alleviating psychological stress and reducing symptoms of common mental problems. SH+ has the potential to be scaled-up as a public health strategy to reduce the burden of mental health problems in healthcare workers exposed to high levels of stress.
This investigation was carried out to study the effect of different concentrations of citric acid and glycine, which are common in freshwaters, on the kinetics of the adsorption of Hg by kaolinite under various pH conditions. The data indicate that Hg adsorption by kaolinite at different concentrations of citric acid and glycine obeyed multiple first order kinetics. In the absence of the organic acids, the rate constants of the initial fast process were 46 to 75 times faster than those of the slow adsorption process in the pH range of 4.00 to 8.00. Citric acid had a significant retarding effect on both the fast and slow adsorption process at pHs of 6.0 and 8.0. It had a significant promoting effect on the fast and slow adsorption process at pH 4.00. Glycine had a pronounced enhancing effect on the rate of Hg adsorption by kaolinite during the fast process. The rise in pH of the system further increased the effect of glycine on Hg adsorption. The magnitude of the retarding/promoting effect upon the rate of Hg adsorption was evidently dependent upon the pH, structure and functionality of organic acids, and molar ratio of the organic acid/Hg. The data obtained suggest that low-molecular-weight organic acids merit close attention in studying the kinetics and mechanisms of the binding of Hg by sediment particulates and the subsequent food chain contamination.
Screen time in infancy is linked to changes in social-emotional development but the pathway underlying this association remains unknown. We aim to provide mechanistic insights into this association using brain network topology and to examine the potential role of parent–child reading in mitigating the effects of screen time.
Methods
We examined the association of screen time on brain network topology using linear regression analysis and tested if the network topology mediated the association between screen time and later socio-emotional competence. Lastly, we tested if parent–child reading time was a moderator of the link between screen time and brain network topology.
Results
Infant screen time was significantly associated with the emotion processing-cognitive control network integration (p = 0.005). This network integration also significantly mediated the association between screen time and both measures of socio-emotional competence (BRIEF-2 Emotion Regulation Index, p = 0.04; SEARS total score, p = 0.04). Parent–child reading time significantly moderated the association between screen time and emotion processing-cognitive control network integration (β = −0.640, p = 0.005).
Conclusion
Our study identified emotion processing-cognitive control network integration as a plausible biological pathway linking screen time in infancy and later socio-emotional competence. We also provided novel evidence for the role of parent–child reading in moderating the association between screen time and topological brain restructuring in early childhood.