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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 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.

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.

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...

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.

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.

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.

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.

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.

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.

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.

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.

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.

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 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.

Manipulations of a constrained object often use a non-rigid grasp that allows the object to rotate relative to the end effector. This orientation slip strategy is often present in natural human demonstrations, yet it is generally overlooked in methods to identify constraints from such demonstrations. In this paper, we present a method to model and recognize prehensile orientation slip in human demonstrations of constrained interactions. Using only observations of an end effector, we can detect the type of constraint, parameters of the constraint, and orientation slip properties. Our method uses a novel hierarchical model selection method that is informed by multiple origins of physics-based evidence. A study with eight participants shows that orientation slip occurs in natural demonstrations and confirms that it can be detected by our method., Comment: 2021 International Conference on Robotics and Automation (ICRA 2021)

In this paper, a hybrid underwater profiler with thrusters (HUPT) used for fixed-point ocean observation is presented. A gravity center adjustment module(GCAD) is proposed. It can move two rotating moving mass simultaneously by using one motor which contributes to reducing cost and power consumption. We also propose an attitude adjustment approach to change the yaw angle and the pitch angle rapidly and efficiently based on the lateral thruster and the moving mass respectively. To reach a fixed-point, one kind of motion strategy is put forward which is able to reduce the impact of currents and make the HUPT stay in a fixed activity space.

Theory of self-organization, i.e., scale-dependent feedback (SDF), has been widely used to explain mechanisms of spatial patterns in different ecosystems. Studies have demonstrated that self-organization is one of the mechanisms through which ecosystem resilience is maintained. However, the application of SDF in real ecological restoration practices is a challenge due to the lack of a controlled experimental validation. In the present study, multiple scales of vegetation patches were constructed along an elevation gradient in the saltmarsh ecosystem on Nanhui coasts and were investigated to verify if there was an effect of SDF. Results of the density-variation curves analyses revealed that most constructed self-organized patches could survive and an optimal curve was found of which the density-dependent feedback was proven through fitting with the asymptotic regression model. The large vegetation patches exhibited considerable increases in density when compared to the small vegetation patches, which occurred in challenging environments, i.e., on the verges of elevation thresholds, and with a tendency to shrink. Analyses using one-way ANOVA revealed that there was an optimal patch scale and elevation in the study area, i.e., 1 m × 1 m scale and 3.2 m, respectively. Optimal scale and elevation provide a comprehensively explanations of SDF, although with the positive effects gradually decreased along the distance away from the optimal condition. The present study provides novel insights on applying the theory of SDF in facilitating the restoration process of coastal saltmarshes.

In this paper, a modeling and control framework of the two-wheel steering unmanned bicycle is presented. We first build the dynamic model of the unmanned bicycle using Lagrange method. And then balance controllers for stationary and moving cases are designed. Simulation results show that the stationary bicycle can keep balance only by the swinging balancer, and the linear quadratic regulator (LQR) controller for moving case works well. Our experimental results about LQR controller are also given.

This study reports on the development of a fast and efficient method based on headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–tandem mass spectrometry (GC–MS/MS) for simultaneous analysis of 128 volatile or semi-volatile pesticide residues belonging to nine classes of pesticides. The important factors related to HS-SPME performance were optimized; these factors include fiber types, water volume, ion strength, extraction temperature, and extraction time. The best extraction conditions include a PDMS/DVB fiber, and analytes were extracted at 90 °C for 60 min from 1 g of tea added to 5 mL of 0.2 g mL−1 NaCl solution. The methodology was validated using tea samples spiked with pesticides at three concentration levels (10, 50, and 100 μg kg−1). In green tea, oolong tea, black tea, and puer tea, 82.8, 88.3, 79.7, and 84.3% of the targeted pesticides meet recoveries ranging from 70 to 120% with a relative standard deviation of ≤ 20%, respectively, when spiked at a level of 10 μg kg−1. Limits of quantification in this method for most of the pesticides were 1 or 5 μg kg−1, which are far below their maximum residue limits prescribed by EU. The optimized method was employed to analyze 30 commercial samples obtained from local markets; 17 pesticide residues were detected at concentrations of 2–452 μg kg−1. Chlorpyrifos was the most detected pesticide in 80% of the samples, and the highest concentration of dicofol (452 μg kg−1) was found in a puer tea. This is the first time to find that the optimized extraction temperature for pesticide residues is 90 °C, which is much higher than other reported HS-SPME extraction conditions in tea samples. This developed method could be used to screen over one hundred volatile or semi-volatile pesticide residues which belong to multiple classes in tea samples, and it is an accurate and reliable technique.

Sodium ion batteries (SIBs) are applied to the field of energy storage due to their unique advantages, however, large scale energy storage equipment, also requires low cost, good cycling performance, safety performance and good environmental adaptation performance, in order to cope with various climatic conditions. The polyanionic material Na3.12Fe2.44(P2O7)2(NFPO) is considered to be an excellent cathode material for SIBs due to its unique large frame work structure and good thermal stability, leading to good cycle stability and a wide working temperature. Nevertheless, poor intrinsic conductivity of the material brings about large polarization, resulting in low electrochemical reversibility. Especially in high temperature environment, the electrolyte aggravates the erosion of the material and increases the side reactions, making the cycle stability worse. In this study, nanoscale NFPO composites are synthesized by an optimized sol–gel method, while the interface is modified using AlF3, to achieve resistance to surface oxidation and corrosion. Impressively, these modified materials exhibit high-temperature electrochemical properties due to the thermal stability and interfacial protection of AlF3. At 60 °C, it provides a discharge capacity of 130 mAh g−1 at 0.1C, still has a discharge capacity of 100.4 mAh g−1 at 10C, a capacity retention rate of 96.3% after 400 cycles, and has excellent long-term cycling performance (70% capacity retention rate after 6000 cycles at 50C). This work demonstrates the effectiveness of the interfacial modification and provides an impactful strategy for the design of batteries at high temperatures.

At high altitudes, an Aviation Oxygen Supply System (AOSS) protects pilots from low pressure and hypoxia by continuously providing oxygen corresponding to the pilots’ dynamic respiratory properties. An AOSS mainly consists of oxygen supercharging machines which are used in a high-altitude flight cabin to supply pressurized oxygen to pilots. Therefore, it is of great significance to study the airflow dynamic characteristics of an AOSS for safe, continuous, and efficient oxygen supply. In this paper, an AOSS is firstly simplified and considered as a mechanical ventilation system. Then, its corresponding mathematical model is constructed. Next, to verify the mathematical model, a prototype AOSS with a lung simulator is proposed for an experimental study. Afterwards, to build a foundation for the optimization of the AOSS, the airflow dynamic characteristics of an aircraft are analyzed, and the effects of key parameters on the respiration system are researched. Through experimental and simulation studies, it can be concluded that the mathematical model is effective. Subsequently, for stability during the respiration process, we consider setting the equivalent throttling areas of the inspiration and expiration pipelines smaller within certain limits; additionally, an excessively high oxygen supply pressure will disturb smooth airflow, and in a low-pressure environment, the pressure can be 84 cmH2O lower than the standard atmospheric pressure. This research can be referred to in the design of an oxygen supply system and the study on optimization of airflow dynamic characteristics.

The nanoscale quasicrystals (NQs), amorphous and ultrafine nanocrystals (UNs) modified hard composites are produced by laser cladding (LC) of the Ni60A-TiC-NbC-Sb mixed powders on the additive manufacturing (AM) TA1 titanium alloy. The LC technique is favorable to formations of icosahedral quasicrystals (I-phase) with five-fold symmetry due to its rapid cooling and solidification characteristics. The formation mechanism of this I-phase is explained here. Under the actions of NQs, amorphous and UNs, such LC composites exhibited an extremely high micro-hardness. UNs may also intertwin with amorphous, forming yarn-shape materials. This research provides essential theoretical basis to improve the quality of laser-treated composites.

Purpose The indentation behaviour of sandwich panels is significant to incipient damage and is known to be affected by a number of dominant parameters. However, it is challenging not only to demonstrate how those few dominant parameters influence the indentation behaviour but also to ascertain that such influence was coupled to the variation of the other dominant parameters. The paper aims to discuss these issues. Design/methodology/approach In this work, the authors adopted a controllable quasi-static testing to carry out a diagnostic interrogation on the nature of incipient damage in laminate-skinned sandwich panels using hemispherical indenter and used photographs taken from the cross-sections of all the cut-up tested specimens, which were stopped both just before and after the initial critical loads, respectively, to confirm the mechanism of the incipient damage. Sandwich panels with aluminium honeycomb core had carbon/epoxy skins of two different thicknesses and lay-ups and hemispherical nosed indenter had three different diameters. Findings The authors found that: the incipient damage mechanism in all the panels was combined delamination in the skin and core crushing without debonding; doubling the skin thickness had the significant enhancement on critical load and indentation and this enhancement became greater for the larger indenter diameters; the indenter diameter had the moderate effect on critical load in the thick panels from 8 to 14 mm but had the negligible effect on thin panels and no effect on the thick panels from 14 to 20 mm; varying the skin lay-up or support had little effect on the indentation behaviour. Research limitations/implications These findings were limited to the constant core density and core thickness. Varying the former significantly could alter the findings accordingly. Practical implications The results of this work should be tremendously useful to design and analysis in industrial applications of sandwich structures in aircraft, vehicles, marine vessels and transport carriages for situations involving localised loading and deformation. Originality/value The results of this research work is one of the very few that demonstrated a systematic understanding of the indentation behaviour characteristics of sandwich construction, which is vital to the establishment of indentation law for sandwich structures in future.

Background: Since December 2019, Novel coronavirus pneumonia has been reported from Wuhan, China, we try to analysis the clinical, biological and epidemiologica

In order to meet the requirements of Mars rover test, the Mars surface illumination environment simulation system was developed, which is mainly composed of optical subsystem, mechanical and control subsystem. It can simulate the solar elevation angle at a large angle and solar spectrum on Mars surface, etc. It is of great significance for development of Mars rover and the improvement of its ability to perform space exploration missions. After the system was developed, six indexes including irradiance, spectrum, solar elevation angle, illumination area, irradiation uniformity and irradiation stability were evaluated according to the test standards. The irradiance meets the requirement of 0.3 solar constant in the direction of vertical illumination. The spectrum meets the spectral requirements of the landing area; Mars surface illumination environment simulation system can be simulated 75° ~ 90° solar elevation angle, at the same time can be simulated illumination area of more than 10 m × 10 m; The irradiation non-uniformity of this system is ±14% ;Irradiation stability is expressed by irradiation instability, and the irradiation instability of the system is ±4.5% within 2 hours continuously. At present, the Mars surface illumination environment simulation system has participated in the Mars rover test, and the illumination effect has been affirmed by the test department.

Based on photogrammetry, antenna deformation measurement in vacuum and cryogenic environment has been widely carried out. The strength of measuring network will affect the accuracy, repeatability and stability of the measured results. A method for evaluating the strength of photogrammetric network based on attenuation factor is proposed, that is, a strong correlation is established between the measurement accuracy and spatial network parameters through the formula of attenuation factor of network strength ,according to the factor value, the network layout can be evaluated . In this paper, the reliability of this method is verified by experiments. The method can obtain a better network design before measurement and avoid a lot of repetitive work. The evaluation method is applied to deformation measurement test for large aperture antenna in the vacuum and cryogenic environment .Thus reduces the test cost and the risk, enhances the measurement accuracy and the stability.

In this work, fungal hyphae (FH, Irpex lacteus) was used as the carbon resource for the preparation of porous carbon materials (PCFH) using mixed alkali as the activator. The SEM, N2 adsorption/desorption, FT-IR, XRD, Raman, and XPS were used to characterize the structure and surface properties of PCFH. The results showed that the PCFH not only has a huge Brunauer–Emmett–Teller (BET) surface area (2480 m2 g−1), but also has abundant functional groups containing carbon, oxygen, and nitrogen. Rhodamine B (RhB) was selected to evaluate the adsorption properties of the PCFH prepared under different conditions in dyeing wastewater. A fast adsorption rate was observed, and an uptake capacity of 765 mg g−1 was achieved in the initial 5 min. The maximum adsorption capacity of PCFH to RhB reached 1912 mg g−1 at the pH value of 9, which could efficiently remove RhB from the aqueous solution. The adsorption process was fitted better by a pseudo-second order model, and the adsorption isotherm for the RhB was well fitted by the Freundlich model. Moreover, the probable mechanism of adsorption was analyzed. In short, the good adsorption performance of PCFH indicated that it has a broad application prospect for dye water pollution control.

Lignocellulose is the primary component of many biomasses, including corn straw. Herein, lignocellulose in corn straw was disassembled into the individual polymers, cellulose, hemicellulose, and lignin via a mild and facile method. Subsequently, three porous carbon materials were prepared by carbonization and chemical activation of cellulose (PCCC), hemicellulose (PCHC), and lignin (PCLC). The three materials showed higher specific surface areas (2565.7, 2996.1, and 2590.3 m2 g−1) and higher porosities (1.4261, 1.5876, and 1.2406 cm3 g−1) than that of PCCS, a porous carbon material derived from raw corn straw (1993 m2 g−1 and 1.19 cm3 g−1). Of note, PCCC and PCHC exhibited higher adsorption (1025.5 and 950.1 mg g−1) of brilliant green (BG), than PCCS (876.7 mg g−1). Besides, the BG adsorption capacities of the designed materials were higher than that of most adsorbents, and 2–2.5 times higher than that of graphite oxide (416.7 mg g−1). These study results indicate that the disassembly of lignocellulosic biomass into cellulose, hemicellulose, and lignin is an effective strategy for preparing various porous carbon materials with enhanced performances.

// Yuyan Na 1,2,* , Rui Bai 1,* , Zhenqun Zhao 1 , Yishan Wei 1 , Daihe Li 1 , Yong Wang 1 , Chao Sun 1 , Liang Sun 1 , Bolun Zhang 1,2 , Tianbo Jin 3,4 and Wanlin Liu 1 1 Department of Pediatric Orthopedics, The Second Affiliated Hospital of Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, China 2 Graduate School of Inner Mongolia Medical University, Hohhot, Inner Mongolia Autonomous Region, China 3 Xi’an Tiangen Precision Medical Institute, Xi’an, Shaanxi, China 4 National Engineering Research Center for Miniaturized Detection Systems, School of Life Sciences, Northwest University, Xi’an, Shaanxi, China * These authors have contributed equally to this work Correspondence to: Wanlin Liu, email: // Tianbo Jin, email: // Keywords : knee OA; IL1R1; genetic polymorphism; case-control study Received : August 11, 2016 Accepted : December 07, 2016 Published : December 14, 2016 Abstract IL1R1 , encoding interleukin 1 receptor type 1, is located in the IL-1 gene cluster and is involved in the pathogenesis of hand, hip, and knee osteoarthritis (OA) in different ethnicities. However, the link between IL1R1 polymorphisms and OA risk in the Chinese Han population is unknown. We studied the association between five IL1R1 polymorphisms (rs10490571, rs12712127, rs956730, rs3917225, and rs3917318) and OA risk by analyzing the genotypes of 298 knee OA patients and 297 controls using Sequenom MassARRAY technology. Logistic regression analysis after adjusting for gender and age revealed significant differences in the allele frequencies of IL1R1 rs956730 and IL1R1 rs3917225 between patients and controls. In addition, IL1R1 rs3917225 was associated with increased risk of knee OA with or without adjustment by age and gender in the dominant model (adjusted OR= 1.47, 95%CI: 1.04-2.07, P = 0.030), the recessive model (adjusted OR= 1.75, 95%CI: 1.08-2.85, P = 0.023), and the additive model (adjusted OR= 1.40, 95%CI: 1.09-1.79, P = 0.007). This study is the first to report that IL1R1 polymorphisms are associated with knee OA susceptibility in the Northwestern Chinese Han population.

Physalis alkekengi L. husk (PH) is a waste product discarded during agricultural production. Improper disposal of large amounts of PH can lead to environmental pollution of water and air. In this work, a porous carbon material was prepared for the first time from PH and denoted as PCPH. The structures and surface properties of PCPH were characterized using TGA, SEM, XRD, FT-IR, N 2 adsorption/desorption, Raman spectroscopy, and XPS. The specific surface area of PCPH was as high as 3502 m2/g, and the total pore volume was 2.24 cm3/g. Malachite green (MG) was used as a model dye for evaluating the adsorption performance of PCPH. When the pH was 9, the maximum adsorption capacity of PCPH reached 1989 mg/g. Fast adsorption of MG reached 1016 mg/g in the first 5 min. The adsorption data of PCPH was fitted with kinetics and isotherm models, and the thermodynamics were analyzed. The adsorption mechanism of MG was also analyzed. The removal rate of MG still reached 89% after 10 cycles. In summary, PCPH has excellent application potential in environmental water pollution treatment.

Edible fungus substrate (EFS) is a kind of agricultural waste produced by the cultivation of edible fungus. Improper handling of a large quantity of EFS may lead to environmental pollution. In this work, three porous carbon materials (PCEFS), derived from EFS, were prepared using simple techniques, including carbonization and chemical activation. Three types of alkalis were used as activators to investigate the different physicochemical properties of PCEFS (PCEFS-MA, PCEFS-K, and PCEFS-Na), which aims to clarify the influence of mixed alkali (MA) on the preparation method. The textural characterization of the PCEFS showed that the treatments produced some of changes, especially in the surface area and the structure of pores. Besides, synthetic dye Rhodamine B (RhB) was selected as the model dye to test the adsorption properties, including the effects of pH, the adsorption kinetics, and the adsorption isotherms. Moreover, the maximum adsorption capacities of 1497 mg g−1, 1103 mg g−1, and 1055 mg g−1 for PCEFS-MA, PCEFS-K, and PCEFS-Na at the pH value of 9 were observed, which were higher than some of the contemporary adsorbents. This study has given evidence that MA can serve as an efficient activator for preparing porous carbon material.

Lower limb length discrepancy (LLD), defined by unequal length of paired lower limbs, contributes to lower back pain, osteoarthritis of the hip, and stress fractures [1–3]. The Center for Disease Control and Prevention estimated that there were approximately 700 children born with LLD each year in US [4]. Patients may receive distraction osteogenesis treatment, in which an osteotomy is performed on the shorter limb, and mechanical force is applied to gradually distract the two halves of the bone during the healing process. This stretches the bone callus during healing to achieve desired limb length upon callus consolidation [5]. The current correction devices are external fixators that leave unsightly scars and are prone to infection [6]. While recently developed intramedullary devices address many of the persistent issues with external lengthening devices, size limitations and potential damage to the bone growth plates make them impractical for use in children [7, 8]. The proposed research addresses an unmet need by developing a novel implantable extramedullary device for LLD correction that is targeted for pediatric use. The device will be implantable, submuscular, and fixed to the outside surface of the bone (extramedullary), thus allowing for use in children without concern for injury to the growth plates. The device’s function will be similar to an external fixator; however, it will not require exposed hardware, which increases risk of infection, or muscle penetration from the pins, which causes pain. Additionally, the device incorporates real-time control of the distraction rate, reducing the risk of complications arising from fixed rate distraction such as premature consolidation and non-union of the callus. [9–11]. The investigators of this study have previously designed and constructed a distraction mechanism prototype and test frame [10]. The current study aims to validate the real-time controller of the prototype.