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The lithium polysulfide (LiPSs) shuttling and slow chemical reactions at the sulfur cathode and the formation of dendritic lithium in metal anodes severely hinder the popularization of lithium-sulfur batteries. Here, a B,N-codoped carbon nanotube (BNCNTs) array decorated with sulfilic and lithiophilic CoSe nanoparticles grown on a carbon cloth (CoSe@BNCNTs/CC) as both a sulfur and a lithium host is reported. Density functional theory (DFT) calculations, simulations, and electrochemical performance determinations demonstrate that CoSe@BNCNTs/CC can simultaneously exert catalytic effects for accelerating LiPSs conversion and realize smooth and uniform lithium deposition to regulate the S and Li electrochemistry. Moreover, the unique structure of the BNCNTs array provides sufficient storage space for sulfur and homogenizes the distribution of Li ions and the electric field of the electrode. The assembled Li-S full battery with a CoSe@BNCNTs/CC dual-functional host exhibits a long-term cycling stability (800 cycles at 0.5 C with a decay rate of 0.066% per cycle) and a high rate capacity (684 mAh g

In this study, we used a combination of chemical and biological pretreatment methods to extract cellulose from corn straw with a relative content of 92.40%. The adsorption performance and mechanism of the prepared porous carbon were investigated using synthetic dye malachite green (MG) and antibiotic tetracycline hydrochloride (TC) as adsorption models. The kinetic studies suggested that the adsorption followed the pseudo-second-order model and Bangham model. The Freundlich isotherm model fitted the adsorption data best for both MG and TC. The thermodynamic studies showed that the adsorption of MG and TC by adsorbents were spontaneous and endothermic in nature. In addition, the adsorption performance was maintained at 50% of the original value after five cycles. More importantly, this method not only improved the adsorption performance of prepared porous carbon materials but also provides a reference for the application of other lignocellulosic materials for cellulose extraction.

The design of optimal guidance law for intercepting a near-space hypersonic maneuvering target with bounded inputs is considered. Firstly, a maneuvering model for near-space hypersonic aircraft is given. Then, the aircraft acceleration prediction can be obtained using this model with two neural networks. By using the target acceleration prediction, which is taken into account when calculating the Zero Effort Miss (ZEM), an optimal sliding-mode guidance law is proposed to fulfill the guidance task. An adaptive sliding-mode switch term is designed to deal with actuator saturation and prediction errors. Finally, numerical simulations show that the proposed guidance law can reduce the energy consumption and the terminal acceleration command of the interceptor effectively.

This study examined the home advantage effect in decisive National Basketball Association Conference Finals and Finals series playoff games from 1979 to 2019 (the 3-point shot era). We also examined the potential contribution of various offensive- and defensive-based skills and whether these skills mediated the relationship between game status (decisive vs. nondecisive) and outcome (win vs. loss). Overall, we found evidence of a home court advantage with the home team winning 63% of the decisive playoff games and 66% of the nondecisive playoff games. After adjusting for multiple comparisons and regular season win percentage, the home team had significantly more defensive rebounds and steals in Game 5 when trailing 3–1 going into that game. Mediation analyses did not reveal any significant findings when examining the impact of decisive game status on performance through offensive and defensive skills, thus suggesting there are other explanations for the home advantage effect.

This study aimed to determine the quality type and importance ranking of hospital signage systems’ usage requirements using the Kano model. This study collected data from 300 users in three hospitals in Guangzhou and evaluated 32 metrics of hospital signage systems. The Kano model questionnaire was used to analyze the quality type of each demand indicator, and the better–worse coefficient was used to calculate the sensitivity and importance ranking of the demand. Of the 32 attributes evaluated by participants, 4 are must-be quality (M), 4 are one-dimensional quality (O), 12 are attractive quality (A), and 12 are indifferent quality (I). The results of this study suggest that the presence of most of the evaluated attributes is associated with maintaining a level of user satisfaction, and the lack of these attributes causes user dissatisfaction. There is a strong demand for basic usage functions and an easy-to-use hospital signage system. In addition, users often wish to add and improve signage functions and have greater expectations for the inclusion of features such as digital intelligence and regional culture in this study. The results of this study show that the Kano model can better derive the user requirements for hospital signage systems and can promote the improvement of hospital signage systems in a more targeted manner, according to the quality type and importance of requirements, providing a research basis for the sustainable development of healthcare services.

BACKGROUND Scholars have used data from in-person interviews, administrative systems, and surveys for sexual violence research. Using Twitter as a data source for examining the nature of sexual violence is a relatively new and underexplored area of study. OBJECTIVE We aimed to perform a scoping review of the current literature on using Twitter data for researching sexual violence, elaborate on the validity of the methods, and discuss the implications and limitations of existing studies. METHODS We performed a literature search in the following 6 databases: APA PsycInfo (Ovid), Scopus, PubMed, International Bibliography of Social Sciences (ProQuest), Criminal Justice Abstracts (EBSCO), and Communications Abstracts (EBSCO), in April 2022. The initial search identified 3759 articles that were imported into Covidence. Seven independent reviewers screened these articles following 2 steps: (1) title and abstract screening, and (2) full-text screening. The inclusion criteria were as follows: (1) empirical research, (2) focus on sexual violence, (3) analysis of Twitter data (ie, tweets or Twitter metadata), and (4) text in English. Finally, we selected 121 articles that met the inclusion criteria and coded these articles. RESULTS We coded and presented the 121 articles using Twitter-based data for sexual violence research. About 70% (89/121, 73.6%) of the articles were published in peer-reviewed journals after 2018. The reviewed articles collectively analyzed about 79.6 million tweets. The primary approaches to using Twitter as a data source were content text analysis (112/121, 92.5%) and sentiment analysis (31/121, 25.6%). Hashtags (103/121, 85.1%) were the most prominent metadata feature, followed by tweet time and date, retweets, replies, URLs, and geotags. More than a third of the articles (51/121, 42.1%) used the application programming interface to collect Twitter data. Data analyses included qualitative thematic analysis, machine learning (eg, sentiment analysis, supervised machine learning, unsupervised machine learning, and social network analysis), and quantitative analysis. Only 10.7% (13/121) of the studies discussed ethical considerations. CONCLUSIONS We described the current state of using Twitter data for sexual violence research, developed a new taxonomy describing Twitter as a data source, and evaluated the methodologies. Research recommendations include the following: development of methods for data collection and analysis, in-depth discussions about ethical norms, exploration of specific aspects of sexual violence on Twitter, examination of tweets in multiple languages, and decontextualization of Twitter data. This review demonstrates the potential of using Twitter data in sexual violence research.

Stimulus-responsive luminescent materials have attracted considerable attention owing to their intensive applications in diverse fields. However, most of the reported materials are based on short-lived luminescence, while those based on...

Purpose: This retrospective cohort study aimed to investigate the value of preimplantation genetic testing for aneuploidy (PGT-A) as a screening test for patients suffered from unexplained recurrent implantation failure (RIF). Methods: After screening patients in one reproductive medicine center, twenty-nine, eighty-seven and thirty-eight women (Results: The live birth rate per transfer was significantly higher in the RIF+PGT-A group than that in the RIF+NO PGT-A group (47.4% vs 31.6%) after adjusting the confounder (the maternal age). After 3 cycles of FET, RIF+PGT-A group had a significantly higher conservative cumulative live birth rate (CLBR) compared to the RIF+PGT-A group (69.0% vs 42.5%, odds ratio [OR] 3.777, p=0.005), but had similar CLBR compared to the NO RIF+PGT-A group (69.0% vs 81.6%). The optimal CLBR in the RIF+PGT-A patients was similar to those in the other 2 groups. The miscarriage rate per clinical pregnancy was not different between the RIF+PGT-A and RIF+NO PGT-A, RIF+PGT-A and NO RIF+PGT-A groups. Conclusion: Although PGT-A could land on the non-beneficial side after three blastocyst FETs, it did be superior in reducing the number of transfer cycles required to achieve a similar live birth rate. Further studies to identify the RIF patients who would benefit most from PGT-A are necessary.

In high frequency AC (HFAC) distribution system, the resonant inverter is used to improve power quality and keep the stability of the output AC voltage. Aiming at the problems of poor output power quality and slow transient performance caused by unreasonable filter parameter design and load change during inverter operation, a single-phase H-bridge LCLC resonant inverter based on analog circuit controller implement is introduced in this paper for HFAC power distribution system (PDS). In this study, to design harmonic compensator and analyze the responsiveness of the inverter, it is necessary to analyze the output voltage total harmonic distortion (THD) of LCLC resonant inverter and the performance of the open loop system in detail. On the one hand, a proportional-integral-resonant (PIR) controller is designed to maintain the zero static error of the voltage output and suppress the output voltage THD of LCLC resonant inverter. On the other hand, an integral controller combines with phase-shift modulation (PSM) method is presented to effectively improve the transient performance of resonant inverter and provide the fixed frequency of the output voltage. On the basis of the above, the experimental prototype is implemented with the output AC voltage root mean square of 28 V, and the output voltage frequency for resonant inverter is equal to switching frequency. A rated output power of 130 W experimental platform is built to verify the effectiveness of the theoretical analysis, control strategy, and modulation method.

The Taoist culture is a precious cultural heritage of the Chinese nation, but in today's era of weak life, how to guide citizens to understand the Taoist culture, understand the true meaning of "your birth, born again", the Taoist culture in the idea of respect for life, love life by heart, externalized in line, to improve the quality of the citizens, strengthen social stability is particularly important. Taoism's idea of "being indifferent to fame and wealth" is also a good medicine for today's society, which provides a better perspective for in-depth study of Taoist culture and a feasible way to promote Taoist culture.

To improve the energy-efficiency of transport systems, it is necessary to investigate electric trains with on-board hybrid energy storage devices (HESDs), which are applied to assist the traction and recover the regenerative energy. In this paper, a time-based mixed-integer linear programming (MILP) model is proposed to obtain the energy-saving operation for electric trains with different constraints of on-board HESDs, such as their capacity, initial state of charge (SOC), and level of degradation. The proposed integrated power flow model based on the train longitudinal dynamics, power split of on-board HESDs, and line impedance is discretized and linearized, aiming to minimize the net energy consumption (NEC). The results reveal that on-board HESDs with a higher capacity does not necessarily lead to a higher energy-saving rate; a lower or excessive initial SOC could undermine the energy-saving potential; considering the long-term train operation, the degradation of the Li-ion battery will influence the energy-saving operation for electric trains, as well as result in an energy-saving rate that ranges from 41.57% to 31.90%. The practical data from Guangzhou Metro Line 7 were applied in the simulations, which enhanced the practicality and effectiveness of the proposed method.

Background Scholars have used data from in-person interviews, administrative systems, and surveys for sexual violence research. Using Twitter as a data source for examining the nature of sexual violence is a relatively new and underexplored area of study. Objective We aimed to perform a scoping review of the current literature on using Twitter data for researching sexual violence, elaborate on the validity of the methods, and discuss the implications and limitations of existing studies. Methods We performed a literature search in the following 6 databases: APA PsycInfo (Ovid), Scopus, PubMed, International Bibliography of Social Sciences (ProQuest), Criminal Justice Abstracts (EBSCO), and Communications Abstracts (EBSCO), in April 2022. The initial search identified 3759 articles that were imported into Covidence. Seven independent reviewers screened these articles following 2 steps: (1) title and abstract screening, and (2) full-text screening. The inclusion criteria were as follows: (1) empirical research, (2) focus on sexual violence, (3) analysis of Twitter data (ie, tweets or Twitter metadata), and (4) text in English. Finally, we selected 121 articles that met the inclusion criteria and coded these articles. Results We coded and presented the 121 articles using Twitter-based data for sexual violence research. About 70% (89/121, 73.6%) of the articles were published in peer-reviewed journals after 2018. The reviewed articles collectively analyzed about 79.6 million tweets. The primary approaches to using Twitter as a data source were content text analysis (112/121, 92.5%) and sentiment analysis (31/121, 25.6%). Hashtags (103/121, 85.1%) were the most prominent metadata feature, followed by tweet time and date, retweets, replies, URLs, and geotags. More than a third of the articles (51/121, 42.1%) used the application programming interface to collect Twitter data. Data analyses included qualitative thematic analysis, machine learning (eg, sentiment analysis, supervised machine learning, unsupervised machine learning, and social network analysis), and quantitative analysis. Only 10.7% (13/121) of the studies discussed ethical considerations. Conclusions We described the current state of using Twitter data for sexual violence research, developed a new taxonomy describing Twitter as a data source, and evaluated the methodologies. Research recommendations include the following: development of methods for data collection and analysis, in-depth discussions about ethical norms, exploration of specific aspects of sexual violence on Twitter, examination of tweets in multiple languages, and decontextualization of Twitter data. This review demonstrates the potential of using Twitter data in sexual violence research.

For the supercritical n-decane horizontally flowing in a rectangular channel of an active regenerative cooling system, a transient thermal–fluid–structure coupling method is employed to investigate the unsteady thermal-hydraulic characteristics and the wall deformation at a starting stage. The temperature distributions of the fluid domain and solid domain along the flow direction are investigated at fixed times as well as at a certain cross section. Streamlines in cross sections are employed to explain the temperature distribution. The velocity and pressure at a fixed point versus time are also given. Besides, the solid deformation is presented according to the uneven pressure distribution and temperature distribution. It is found that the response time is less than 30 s when the heat flux is less than 3.0 MW/m2. A larger heat flux contributes to promoting the steady state. The high-temperature part of the solid domain is close to the heated wall, but the situation is reversed for the fluid domain. This is because a bunch of dead-zone vortices appears in the vicinity of the upper wall of the channel. The maximum deformation is 0.132 mm for the condition of heat flux 3.0 MW/m2 and it is exacerbated by the uneven temperature and pressure distributions on the solid domain.

Video question answering (VideoQA) automatically answers natural language question according to the content of videos. It promotes the development of online education, scenario analysis, video content retrieving, etc. VideoQA is a challenging task because it requires a model to understand semantic information of the video and the question to generate the answer. Firstly, we propose a general framework of VideoQA which consists of a video feature extraction module, a text feature extraction module, an integration module, and an answer generation module. The integration module is the core module, including core processing model, recurrent neural networks (RNNs) encoder and feature fusion. These three sub-modules cooperate to generate the contextual representation, and the answer generation module generates the answer based on it. Then, we summarize the methods in core processing model, and introduce the ideas and applications of the methods in detail, such as encoder-decoder, attention model, and memory network and other methods. Additionally, we introduce the widely used datasets and evaluation criteria, as well as the analysis of experimental results on benchmark datasets. Finally, we discuss challenges in the field of VideoQA and provide some possible directions for future work.

Biodegradable microspheres have been widely used in the field of medicine due to their ability to deliver drug molecules of various properties through multiple pathways and their advantages of low dose and low side effects. Poly (lactic-co-glycolic acid) copolymer (PLGA) is one of the most widely used biodegradable material currently and has good biocompatibility. In application, PLGA with a specific monomer ratio (lactic acid and glycolic acid) can be selected according to the properties of drug molecules and the requirements of the drug release rate. PLGA-based biodegradable microspheres have been studied in the field of drug delivery, including the delivery of various anticancer drugs, protein or peptide drugs, bacterial or viral DNA, etc. This review describes the basic knowledge and current situation of PLGA biodegradable microspheres and discusses the selection of PLGA polymer materials. Then, the preparation methods of PLGA microspheres are introduced, including emulsification, microfluidic technology, electrospray, and spray drying. Finally, this review summarizes the application of PLGA microspheres in drug delivery and the treatment of pulmonary and ocular-related diseases.

To overcome the shortcoming of conventional transarterial chemoembolization (cTACE) like high systemic release, a novel droplet-based flow-focusing microfluidic device was fabricated and the biocompatible poly(lactic-co-glycolic acid) (PLGA) magnetic drug-eluting beads transarterial chemoembolization (TACE) microspheres with tunable size and shell thickness were prepared via this device. Paclitaxel, as a model active, was loaded through O/O/W emulsion method with high efficiency. The size and the shell thickness vary when adjusting the flow velocity and/or solution concentration, which caters for different clinical requirements to have different drug loading and release behavior. Under the designed experimental conditions, the average diameter of the microspheres is 60 ± 2 μm and the drug loading efficiency has reached 6%. The drug release behavior of the microspheres shows the combination of delayed release and smoothly sustained release profiles and the release kinetics differ within different shell thickness. The microspheres also own the potential of magnetic resonance imaging (MRI) visuality because of the loaded magnetic nanoparticles. The microsphere preparation method and device we proposed are simple, feasible, and effective, which have a good application prospect.

Sulfonyl fluorides have widespread applications in many fields. In particular, their unique biological activity has drawn considerable research interest in the context of chemical biology and drug discovery in the past years. Therefore, new and efficient methods for the synthesis of sulfonyl fluorides are highly in demand. In contrast to extensive studies on FSO2 + -type reagents, a radical fluorosulfonylation reaction with a fluorosulfonyl radical (FSO2 . ) remains elusive so far, probably owing to its instability and difficulty in generation. Herein, the development of the first radical fluorosulfonylation of alkenes based on FSO2 radicals generated under photoredox conditions is reported. This radical approach provides a new and general access to alkenyl sulfonyl fluorides, including structures that would otherwise be challenging to synthesize with previously established cross-coupling methods. Moreover, extension to the late-stage fluorosulfonylation of natural products is also demonstrated.

Soil pore water salinity is widely accepted to be the primary influencing factor determining coastal vegetation succession. This study investigated an ecological wetland restoration process on the Nanhui coast, Shanghai, during which seasonal changes in vegetation density, soil salinity, and coastal elevation were recorded in detail. These variables interacted with each other and showed coincident distributions. The whole restoration process was categorized into four periods according to vegetation community dynamics. Regression analysis revealed that elevation, not soil pore water salinity, was the most critical factor influencing the spatial pattern of vegetation survival, expansion, and extinction on the Nanhui coast. From a long-term perspective, the local vegetation extinction pattern may have an irreparable influence on salt marsh succession, especially in environments with intricate hydrological and sedimentary conditions such as the Nanhui coastline. Without intact vegetation communities, deficiencies in coastal ecosystem resilience may cause vegetation extinction under the influence of a strong hydrological environment. The area between vegetation communities and bare tidal flats, the “vulnerable zone”, was a critical area determining the ultimate success of coastal vegetation restoration.

With increasing concerns on transportation decarbonization, fuel cell hybrid trains (FCHTs) attract many attentions due to their zero carbon emissions during operation. Since fuel cells alone cannot recover the regenerative braking energy (RBE), energy storage devices (ESDs) are commonly deployed for the recovery of RBE and provide extra traction power to improve the energy efficiency. This paper aims to minimize the net hydrogen consumption (NHC) by co-optimizing both train speed trajectory and onboard energy management using a time-based mixed integer linear programming (MILP) model. In the case with the constraints of speed limits and gradients, the NHC of co-optimization reduces by 6.4% compared to the result obtained by the sequential optimization, which optimizes train control strategies first and then the energy management. Additionally, the relationship between NHC and employed ESD capacity is studied and it is found that with the increase of ESD capacity, the NHC can be reduced by up to 30% in a typical route in urban railway transit. The study shows that ESDs play an important role for FCHTs in reducing NHC, and the proposed time-based co-optimization model can maximize the energy-saving benefits for such emerging traction systems with hybrid energy sources, including both fuel cells and ESD.

We present the tunable multiple plasmon-induced transparency (PIT) in the terahertz region by using a metamaterial made of two graphene bands and a graphene square ring. As the different modes of multiple PIT effects are independent of each other, the physical mechanism behind multiple PIT effects can be revealed by CMT theory. The PIT window changes significantly with the Fermi energy levels and structural parameters of graphene. The both three resonant frequencies increase linearly with the parameters and the Fermi energy changing, which can exhibit high sensitivities and figure of merit (FOM). Meanwhile, the amplitude modulation system can reach 99.63%, which can achieve excellent photoelectric switching. In addition, the group index can be as high as 2739. Therefore, the graphene-based metamaterial could be widely used in switches, modulators, excellent slow-light functional devices and filters in the terahertz region.

Topological charge (TC) is generally acknowledged as an important attribute of an optical vortex (OV), which indicates the twisted characterization of the wavefront. In most circumstances, the TC remains constant as an integer or fraction along the azimuthal direction. Herein, by transforming the TCs into the trigonometric functions of the azimuthal angle to tailor the spiral phase distributions, we numerically demonstrate generating perfect vortex beams (PVBs) with sine-function TC based on the all-dielectric geometric metasurfaces, whose unit structure is optimized to an ideal half-wave plate. To seek the intrinsic advancements of the proposed PVBs, their orbital angular momentum (OAM) as well as optical gradient force distributions are calculated for diverse particle manipulation. We believe our proposed scheme is desired to provide an original thought for OAM manipulation, information storage, and optical communication.

BACKGROUND Previous research has shown that immediate emotions and cognitive processing of the stakes of outcomes influence decision-making under uncertainty. The effect of perceived beneficial stakes and different types of immediate emotions on decision-making is an important topic that has received little attention in the literature. This study investigated the effects of trait anxiety and anticipatory emotions (fear, sadness, excitement and comfortability) on the perception of thee stakes of outcomes and behavioral intentions. METHOD Participants from the community completed a task measuring anticipatory emotions and their perceived stakes of risky and beneficial outcomes in a range of uncertain situations. Trait anxiety was also measured. RESULTS Results revealed that anticipatory emotions (except for sadness), trait anxiety and subjective stakes all demonstrated significant associations with risky behavioral intention in uncertain situations. Anticipatory emotions, but not trait anxiety, had stable effects on stake perceptions. However, trait anxiety moderated the effect of excitement on risky behavioral intention. In addition, positive emotions (comfortability and excitement) and beneficial stakes demonstrated consistent effects in the decision-making process. CONCLUSIONS The current study sheds light on future immediate-emotion-based interventions for deficits in uncertain decision-making.

Chinese New Year prints constitute a significant component of the country’s cultural heritage and folk art. Yangliuqing New Year prints are the most important and widely circulated of all the different kinds of New Year prints. Due to a variety of factors including societal change, industrial structure change, and economic development, New Year prints, which were deeply rooted in agricultural society, have been adversely impacted, and have even reached the brink of disappearance. With the protection and effort from the government and researchers, New Year prints can finally be preserved. However, the underlying problems remain, such as receiving little attention, a singular product form, and being unable to keep up with the times, especially among the younger generation. In this paper, the researchers first processed Yangliuqing New Year prints through the GANs model. Then, the image is segmented by binarization and color extraction of images from the Pop art dataset by the K-Means algorithm, followed by colorizing the binarized and segmented image. Finally, usable high-quality Pop art style Yangliuqing New Year prints are generated. The generated images are used in the development of cultural and creative products. Questionnaires were then distributed based on the empirical research scale. The results of this study are as follows: 1. The method proposed in this study can generate high-quality Pop art style New Year prints. 2 Using Pop art style New Year print images in the design of cultural and creative products is popular among the younger generation, and they possess a great propensity to purchase. This study solves the problems encountered by the current cultural heritage of New Year prints, and broadens the artistic expression forms and product categories, and provides research ideas for the cultural heritage of the same type that is facing similar problems. In the future, researchers will continue to explore the incorporation of AI technology in New Year prints to stimulate the vitality of traditional cultural heritage.

Erratum to “Creating perfect composite vortex beams with a single all-dielectric geometric metasurface.” [Opt. Express 30, 40231 (2022)10.1364/OE.475158]. Here are some mistakes in the paper, which needs to be revised.

Combined peening composed of multiple peening processes or peening media is a surface treatment method for comprehensive control of the macro shape and performance of the part. Compared to combined peening, the impact kinetic energy of the combined hammering can be easier to control over a wide range, and the hammer tool head size is larger than the shot. This paper focused on investigating the effect of combined hammering treatment, 6 mm and 14 mm tool heads with peening density 3.7 to 4.2/mm2, on the variable scale evolution of titanium TA2. Three types of contact relation between the tool head and existing dimple were proposed for impacting at the same position. The size of the dimple of combined hammering varies in width or depth direction, resulting in nest morphology composed of different size dimples. The cross-section microstructure of the test plate was observed, and the gradient changes of dislocation, slip, and grain size are smoothed by combined hammering. The change in hammer tool head size makes the target plastic deform at different depths. The hammering sequence has a significant influence on the evolution of stress and strain fields. When the tool head is first large and then small, a large compressive residual stress near the surface is introduced, about 1000 Mpa; on the contrary, the compressive residual stress distributes uniformly in the depth direction, with an affected layer depth of about 4.4 mm. The measured dimple size and residual stress verified the reliability of the simulation results.

For patients with mechanical ventilation, secretions in airway are harmful and sometimes even mortal, it's of great significance to clear secretion timely and efficiently. In this paper, a new secretion clearance method for VCV (volume-controlled ventilation) ventilator is put forward, and a secretion clearance system with a VCV ventilator and double lungs is designed. Furthermore, the mathematical model of the secretion clearance system is built and verified via experimental study. Finally, to illustrate the influence of key parameters of respiratory system and secretion clearance system on the secretion clearance characteristics, coupling effects of two lungs on VCV secretion clearance system are studied by an orthogonal experiment, it can be obtained that rise of tidal volume adds to efficiency of secretion clearance while effect of area, compliance, and suction pressure on efficiency of secretion clearance needs further study. Rise of compliance improves bottom pressure of secretion clearance while rise of area, tidal volume, and suction pressure decreases bottom pressure of secretion clearance. This paper can be referred to in researches of secretion clearance for VCV.

Optical vortex beam carrying orbit angular momentum has been extensively researched and applied recently. Among which a perfect vortex beam (PVB) has attracted much attention owing to its topological charge (TC)-irrelevant intensity profile. However, the morphology singularity, as well as implementation complexity of the PVB tie the degree of freedom for multiplexing. Herein, by introducing the concept of a composite vortex beam, we originally propose a novel kind of PVB – perfect composite vortex beam (PCVB) – which possesses a rosette-like intensity pattern that is exactly correlated with the TC and can be directly generated using a single all-dielectric geometric metasurface rather than bulky optical systems. We numerically simulate the broadband generation of the proposed PCVB with various TCs, sizes, and rotation angles. To further explore the potential of our design in practical applications, we demonstrated the coaxial array of the PCVBs and detected their optical angular force for manipulating nanoparticles. We believe that our fruitage may pave a desirable avenue for optical communication, information processing, and optical manipulation.

This work investigates the stability of admittance type haptic devices in the context of a wider range of impedances than previously considered. More specifically, we consider the stable range of mass and damping. The coupled human driving impedance, actuator position control bandwidth, and loop delay are identified as major factors affecting the range of stable impedances. Finally, theoretical results are experimentally verified using a custom one degree of freedom admittance type haptic device.

To understand how the realism of a kinesthetic haptic rendering is affected by the accurate selection of the rendering model parameters, we conducted a preliminary user study where subjects compared three real-world objects to their equivalent haptic rendering. The subjects rated the rendering realism as the model parameters were varied about their nominal values. The results suggest that the required accuracy of various haptic rendering parameters is not equally important when considering the perceived realism.

Mining activities and high geological background are considered the important factors causing heavy metal(loid)s accumulation in rice fields of karst area. In this study, the contents, main sources, and the factors influencing bio-availability of heavy metal(loid)s were determined using conditional inference tree (CIT), random forest (RF), and geostatistical analyses with 105 soil samples collected from rice fields in karst area. Contamination by Cd, Hg, As, and Pb in soil was relatively serious in the study area in which the compound pollution was highly similar to that in the flooded area. CIT and RF effectively identified the contributions of natural and anthropogenic inputs of soil heavy metal(loid)s. Concentrations of Pb, As, and Hg were closely associated with human inputs whose cumulative contribution rates reached 68%, 87%, and 86%, respectively. Industrial activities (28%) and geogenic characteristics (44%) were primary sources of Cd accumulation. The soil pH, soil organic matter (SOM), distance from city center, the contents of heavy metal(loid)s in soil, and industry type were the most important factors influencing bio-availability of heavy metal(loid)s. Combined effect of multiple metals could not be ignored, in which As and Cd contributed over 80% to total non-carcinogenic risks for adults and children.

BackgroundThe purpose of this study is to explore the influence of endometrial thickness (EMT) before embryo transfer on birth weight after in vitro fertilization–frozen-embryo transfer (IVF–FET).MethodsThis was a retrospective cohort study. We collected the medical records associated with singleton live births from Tianjin Central Obstetrics and Gynecology Hospital from June 2015 to February 2019 after IVF–frozen-embryo transfer (FET). Patients were ≤ 42 years at delivery. Outcomes related to newborns were birth weight, gestational age, delivery mode, low birth weight, and prevalence of macrosomia. Outcomes related to pregnant women were gestational hypertension, gestational diabetes mellitus, premature rupture of membranes and placenta previa.ResultsThe birth weight of singleton newborns was higher for newborns delivered by patients with EMT > 12 mm before embryo transfer than newborns delivered by patients with a thinner endometrium. Regression analysis showed that the EMT ≥ 12 mm group had a gain in mean birth weight of 85.107 g compared with that in the EMT 12 mm) + 123.483×(hypertension during pregnancy) + 148.859×(premature rupture of membranes) + 182.342×(placental position) − 126.242×(newborn sex) + 23.837×(number of days of pregnancy) + 130.487×(delivery mode) − 55.023×(number of implanted embryos) − 6.215×FSH level − 1.124×E2 level + 22.218×BMI − 4468.101.Conclusion(s)EMT before embryo transfer in patients undergoing their first freeze–thaw embryo transfer cycle is related to the weight of newborn singletons. The newborn birth weight for patients with a thinner endometrium is lower. EMT should be increased before embryo transfer to improve neonatal outcomes after fertility treatment.

Background: It has not been fully elucidated whether the change of the uterus flora is correlated to impaired fecundity. This case-control study aimed to analyze the differences in uterus microbial flora between women with post-cesarean section (CS) scar diverticulum (PCSD) (CS group) and women after vaginal delivery (control group), exploring the correlation between differentially expressed microbial flora and inflammation.Methods: Infertile women who underwent hysteroscopy were enrolled in this case-control study. The swab samples were classified into four subgroups: CS cervix group, CS endometrium group, control cervix group, and control endometrium group. The total DNA obtained from 16 women (a total of 31 samples, the cervix or endometrium) was extracted for 16S recombinant DNA (rDNA) analysis. The Luminex platform was used to detect the abundance of 34 kinds of local inflammatory cytokines in 32 endometrium samples, and the correlation between microbial flora and inflammatory cytokines was analyzed.Results: The alpha and beta diversity analysis indicated that the microbial diversity was higher in the CS group compared to the control group, especially in endometrium tissues. The heatmaps revealed that the microbial flora structure differs at each level of the phylum-class-order-family-genus among the groups. The analysis of four of the most prominently changed microbial flora revealed that Lactobacillus in the cervix was significantly higher in the control group when compared with the cesarean section group (P < 0.05). Furthermore, Proteobacteria and Neisseriaceae had a higher abundance in the CS groups, especially in the cervical tissue (P < 0.05), while Staphylococcaceae increased only in the CS endometrium tissue (P < 0.05). Next, these women were re-divided into the high- and low-Staphylococcaceae, and the abundance of 34 kinds of local inflammation cytokines was compared between groups. It was found that there was a positive correlation between Staphylococcaceae and IL-2, and a negative correlation between Staphylococcaceae and IL-8 (P < 0.05).Conclusion: The present results suggest that the disrupted uterus microbiota composition in women with CS may be closely associated with local inflammation. The interplay between the microbiota and the immune system may be linked to clinical disorders. The potential mechanisms require further exploration.

Background To provide participants with a more real and immersive intervening experience, virtual reality (VR) and/or augmented reality (AR) technologies have been integrated into some bystander intervention training programs and studies measuring bystander behaviors. Objective We focused on whether VR or AR can be used as a tool to enhance training bystanders. We reviewed the evidence from empirical studies that used VR and/or AR as a tool for examining bystander behaviors in the domain of interpersonal violence research. Methods Two librarians searched for articles in databases, including APA PsycInfo (Ovid), Criminal Justice Abstracts (EBSCO), Medline (Ovid), Applied Social Sciences Index & Abstracts (ProQuest), Sociological Abstracts (ProQuest), and Scopus till April 15, 2020. Studies focusing on bystander behaviors in conflict situations were included. All study types (except reviews) written in English in any discipline were included. Results The search resulted in 12,972 articles from six databases, and the articles were imported into Covidence. Eleven studies met the inclusion and exclusion criteria. All 11 articles examined the use of VR as a tool for studying bystander behaviors. Most of the studies were conducted in US young adults. The types of interpersonal violence were school bullying, dating violence, sexual violence/assault, and soccer-associated violence. VR technology was used as an observational measure and bystander intervention program. We evaluated the different uses of VR for bystander behaviors and noted a lack of empirical evidence for AR as a tool. We also discuss the empirical evidence regarding the design, effectiveness, and limitations of implementing VR as a tool in the reviewed studies. Conclusions The reviewed results have implications and recommendations for future research in designing and implementing VR/AR technology in the area of interpersonal violence. Future studies in this area may further contribute to the use of VR as an observational measure and explore the potential use of AR to study bystander behaviors.

Belief propagation (BP) is widely used to solve the cooperative localization problem due to its excellent performance and natural distributed structure of implementation. For a mobile agent network, its factor graph inevitably encounters loops. In this case, the BP algorithm becomes iterative and can only provide an approximate marginal probability density function of the estimate with finite iterations. We propose an augmented-state BP algorithm for mobile agent networks to alleviate the effect of loops. By performing state augmentation, the messages in the factor graph will actually be allowed to be backward propagated, which reduces the number of loops in the factor graph, increases the available information of agents, and thus, benefits the localization. Experimental results demonstrate the better performance of the proposed algorithm over the original BP method.

Considering the unknown compound interference in manufacturing systems, the finite-time tracking and synchronization performance of the multi-motor system significantly affects the production safety, reliability, and quality, which can be considered a multi-agent system with unmeasured speed and uncertainty. In recent years, the synchronous control schemes of the multi-motor system have grown to maturity, but the research on the speed sensorless finite-time consensus tracking control remains to be extended. This paper proposes an observer-based leader–follower consensus tracking control for the synchronous coordination control of the multi-motor system. The speed and position of all motors can be tracked by consensus in a finite time when only some motors realize partial interaction. First, a finite-time observer is designed to estimate the unknown composite disturbance and unmeasurable speed variable of each motor. Second, the distributed finite-time consensus tracking control protocol is designed using the observed value and local information interaction. The stability of the overall closed-loop system is theoretically analyzed based on Lyapunov theory and graph theory, which shows that the consensus tracking error converges to an arbitrary small neighborhood of zero, and all signals are globally bounded in finite time. Finally, simulation results are provided to illustrate the effectiveness of the proposed control method.