To estimate the incidence of foodborne gastroenteritis caused by nontyphoidal Salmonella enterica, Shigella, and Vibrio parahaemolyticus in China, population surveys and sentinel hospital ...surveillance were implemented in six provinces from July 2010 to July 2011, and a multiplier calculation model for the burden of disease was constructed. The multiplier for salmonellosis and V. parahaemolyticus gastroenteritis was estimated at 4,137 95% confidence interval (CI) 2,320-5,663, and for shigellosis at 4,356 (95% CI 2,443-5,963). Annual incidence per 100,000 population was estimated as 245 (95% CI 138-336), 67 (95% CI 38-92), and 806 (95% CI 452-1,103) for foodborne salmonellosis, shigellosis, and V. parahaemolyticus gastroenteritis, respectively, indicating that foodborne infection caused by these three pathogens constitutes an important burden to the Chinese healthcare system. Continuous implementation of active surveillance of foodborne diseases, combined with multiplier models to estimate disease burden, makes it possible for us to better understand food safety status in China.
Highlights • SLAM family receptors, associated with SAP adaptors, play key roles in immunity. • SLAM receptors can be either activating or inhibitory, depending on the context. • The SLAM family has ...been implicated in a wide range of human diseases. • One SLAM family receptor, SLAMF7, is a drug target in multiple myeloma.
Bubble propulsion and self-diffusiophoresis are two common mechanisms that can drive autonomous motion of microparticles in hydrogen peroxide. Although microtubular particles, when coated with ...platinum in their interior concave surfaces, can propel due to the formation and release of bubbles from one end, the convex Janus particles usually do not generate any visible bubble. They move primarily due to the self-diffusiophoresis. Coincidentally, the platinum films on those particles were typically coated by physical evaporation. In this paper, we use a simple chemical deposition method to make platinum–polystyrene Janus dimers. Surprisingly, those particles are propelled by periodic growth and collapse of bubbles on the platinum-coated lobes. We find that both high catalytic activity and rough surface are necessary to change the propulsion mode from self-diffusiophoresis to bubble propulsion. Our Janus dimers, with combined geometric and interfacial anisotropy, also exhibit distinctive motions at the respective stages of bubble growth and collapse, which differ by 5−6 orders of magnitude in time. Our study not only provides insight into the link between self-diffusiophoresis and bubble propulsion but also reveals the intriguing impacts of the combined geometric and interfacial anisotropy on self-propulsion of particles.
This paper addresses the model-free nonlinear optimal control problem based on data by introducing the reinforcement learning (RL) technique. It is known that the nonlinear optimal control problem ...relies on the solution of the Hamilton–Jacobi–Bellman (HJB) equation, which is a nonlinear partial differential equation that is generally impossible to be solved analytically. Even worse, most practical systems are too complicated to establish an accurate mathematical model. To overcome these difficulties, we propose a data-based approximate policy iteration (API) method by using real system data rather than a system model. Firstly, a model-free policy iteration algorithm is derived and its convergence is proved. The implementation of the algorithm is based on the actor–critic structure, where actor and critic neural networks (NNs) are employed to approximate the control policy and cost function, respectively. To update the weights of actor and critic NNs, a least-square approach is developed based on the method of weighted residuals. The data-based API is an off-policy RL method, where the “exploration” is improved by arbitrarily sampling data on the state and input domain. Finally, we test the data-based API control design method on a simple nonlinear system, and further apply it to a rotational/translational actuator system. The simulation results demonstrate the effectiveness of the proposed method.
Major depressive disorder (MDD) is a highly prevalent psychiatric disorder, and inflammation has been considered crucial components of the pathogenesis of depression. NLRP1 inflammasome-driven ...inflammatory response is believed to participate in many neurological disorders. However, it is unclear whether NLRP1 inflammasome is implicated in the development of depression.
Animal models of depression were established by four different chronic stress stimuli including chronic unpredictable mild stress (CUMS), chronic restrain stress (CRS), chronic social defeat stress (CSDS), and repeat social defeat stress (RSDS). Depressive-like behaviors were determined by sucrose preference test (SPT), forced swim test (FST), tail-suspension test (TST), open-field test (OFT), social interaction test (SIT), and light-dark test (LDT). The expression of NLRP1 inflammasome complexes, BDNF, and CXCL1/CXCR2 were tested by western blot and quantitative real-time PCR. The levels of inflammatory cytokines were tested by enzyme-linked immunosorbent assay (ELISA) kits. Nlrp1a knockdown was performed by an adeno-associated virus (AAV) vector containing Nlrp1a-shRNA-eGFP infusion.
Chronic stress stimuli activated hippocampal NLRP1 inflammasome and promoted the release of pro-inflammatory cytokines IL-1β, IL-18, IL-6, and TNF-α in mice. Hippocampal Nlrp1a knockdown prevented NLRP1 inflammasome-driven inflammatory response and ameliorated stress-induced depressive-like behaviors. Also, chronic stress stimuli caused the increase in hippocampal CXCL1/CXCR2 expression and low BDNF levels in mice. Interestingly, Nlrp1a knockdown inhibited the up-regulation of CXCL1/CXCR2 expression and restored BDNF levels in the hippocampus.
NLRP1 inflammasome-driven inflammatory response contributes to chronic stress induced depressive-like behaviors and the mechanism may be related to CXCL1/CXCR2/BDNF signaling pathway. Thus, NLRP1 inflammasome could become a potential antidepressant target.
Pandemic or worldwide disease is the greatest issue of all time that not only affects human health but also influences the economic, educational, and other activities of the countries, since malaria ...is among the leading health disease that disrupts the economic system of the country. Therefore, this study aimed to analyze whether educational expenditure and technological innovation influence malarial incidence in emerging economies. This study also examined the role of government effectiveness, government health expenditure, gross domestic growth, human capital, and research and development during the period 2000–2018. Employing panel data approaches, including the slope heterogeneity and cross-sectional dependence, the second-generation unit root test reveals the stationarity of all variables. The study also validated the existence of a long-run relationship between the variables. Based on the asymmetrical distribution properties, this study employed the quantile regression approach. The empirical results asserted that education and technological innovation significantly reduce malarial incidents in the panel economies. Also, government effectiveness, research and development, and human capital adversely affect incidences of malaria. In contrast, gross domestic product is the only factor found that increases malarial incidents during the selected period. Based on the empirical results, this study suggested policy measures that could benefit the governors, policymakers, and scholars.
Through first‐principles calculations, it is found that two lattice‐matched halide double‐perovskites, Cs2NaBiBr6 and Cs2AgBiBr6, have a type‐I band alignment and can form highly miscible alloys in ...which the disordering makes the bandgaps become direct and activates the direct transition from the valence to conduction band edge, leading to a strong optical absorption and high radiative recombination rate. The bandgaps of the alloys are tunable in a wide range of 1.93–3.24 eV, while the lattice constants remain unchanged. This advantage inspires the design of a coherent crystalline matrix based on Cs2(Na,Ag)BiBr6 alloys, in which the Ag‐rich and narrower‐bandgap regions are embedded in the Na‐rich and wide‐bandgap region with lattice‐matched and coherent interfaces. The type‐I band alignment drives the photogenerated excitons into the narrower‐bandgap Ag‐rich regions, so the regions become light‐emitting centers with a high photoluminescence quantum yield (PLQY). The bandgaps of the Ag‐rich regions are tunable, so the color of emitted light can be adjusted, making a broadband emission possible. Such kind of coherent crystalline matrix with high‐PLQY and broadband emission can also be fabricated based on the alloys of other lattice‐matched halide double‐perovskites, demonstrating the flexibility of band structure engineering in the coherent heterostructures of various halide double‐perovskites.
Through embedding narrower‐bandgap alloys in wide‐bandgap alloys, a coherent crystalline matrix based on the alloys of two lattice‐matched halide double‐perovskites, such as Cs2(Na,Ag)BiBr6 alloys, are fabricated and a high photoluminescence quantum yield and broadband light emission are achieved, which demonstrates the flexibility of band structure engineering in coherent heterostructures of various halide double‐perovskites.
Magnetic reconnection in the partially ionized solar chromosphere is studied in 2.5 dimensional magnetohydro-dynamic simulations including radiative cooling and ambipolar diffusion. A Harris current ...sheet with and without a guide field is considered. Characteristic values of the parameters in the middle chromosphere imply a high magnetic Reynolds number of ~10 super(6)-10 super(7) in the present simulations. Fast magnetic reconnection then develops as a consequence of the plasmoid instability without the need to invoke anomalous resistivity enhancements. Multiple levels of the instability are followed as it cascades to smaller scales, which approach the ion inertial length. The reconnection rate, normalized to the asymptotic values of magnetic field and Alfven velocity in the inflow region, reaches values in the range ~0.01-0.03 throughout the cascading plasmoid formation and for zero as well as for strong guide field. The outflow velocity reaches approximate40 km s super(-1). Slow-mode shocks extend from the X-points, heating the plasmoids up to ~8 x 10 super(4) K. In the case of zero guide field, the inclusion of both ambipolar diffusion and radiative cooling causes a rapid thinning of the current sheet (down to ~30 m) and early formation of secondary islands. Both of these processes have very little effect on the plasmoid instability for a strong guide field. The reconnection rates, temperature enhancements, and upward outflow velocities from the vertical current sheet correspond well to their characteristic values in chromospheric jets.
Chiral molecules with opposite handedness exhibit distinct physical, chemical, or biological properties. They pose challenges as well as opportunities in understanding the phase behavior of soft ...matter, designing enantioselective catalysts, and manufacturing single-handed pharmaceuticals. Microscopic particles, arranged in a chiral configuration, could also exhibit unusual optical, electric, or magnetic responses. Here we report a simple method to assemble achiral building blocks, i.e., the asymmetric colloidal dimers, into a family of chiral clusters. Under alternating current electric fields, two to four lying dimers associate closely with a central standing dimer and form both right- and left-handed clusters on a conducting substrate. The cluster configuration is primarily determined by the induced dipolar interactions between constituent dimers. Our theoretical model reveals that in-plane dipolar repulsion between petals in the cluster favors the achiral configuration, whereas out-of-plane attraction between the central dimer and surrounding petals favors a chiral arrangement. It is the competition between these two interactions that dictates the final configuration. The theoretical chirality phase diagram is found to be in excellent agreement with experimental observations. We further demonstrate that the broken symmetry in chiral clusters induces an unbalanced electrohydrodynamic flow surrounding them. As a result, they rotate in opposite directions according to their handedness. Both the assembly and propulsion mechanisms revealed here can be potentially applied to other types of asymmetric particles. Such kinds of chiral colloids will be useful for fabricating metamaterials, making model systems for both chiral molecules and active matter, or building propellers for microscale transport.
Significance Although colloids have been used as molecular analogues for understanding how simple building blocks can assemble into functional materials, they are mostly spherical with isotropic properties. We are still far from truly accessing the diversity of structures desired for either fundamental understanding or technological application. Here, we report the electric-field–directed assembly of asymmetric colloids into clusters that exhibit a ubiquitous type of symmetry in nature: the chirality. We further demonstrate that the chirality induces unbalanced hydrodynamic flow, which causes rotational propulsion of chiral clusters that are fully dictated by their handedness. Both the assembly and propulsion mechanisms discovered can be universal and applied to other types of asymmetric particles. They are also useful in modeling active matter and making microengines.
We investigate gravitational collapse of a spherically symmetric thin shell in the Einstein–Gauss–Bonnet (EGB) gravity. Under the recently proposed 4D limit, we find that the collapsing shell will be ...bounced back at a small radius, without forming a singularity. This bouncing behavior is similar to those of a test particle and a homogeneous spherical dust star, in accordance with the expectation that the Gauss–Bonnet term will modify the small scale behavior of the Einstein gravity. We analyze the causal structure of the dynamic spacetime that represents the bouncing process, finding that the thin shell has an oscillation behavior on the Penrose diagram, which means that the thin shell results in a novel type of black hole with respect to observers outside the event horizon that the collapse forms. We also find that the weak cosmic censorship conjecture holds in this model. Further implications of such a regular gravitational collapse are discussed.
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