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Alfalfa (Medicago sativa) is an important leguminous forage, known as the “The Queen of Forages”. Abiotic stress seriously limits the growth and development of alfalfa, and improving the yield and quality has become an important research area. However, little is known about the Msr (methionine sulfoxide reductase) gene family in alfalfa. In this study, 15 Msr genes were identified through examining the genome of the alfalfa “Xinjiang DaYe”. The MsMsr genes differ in gene structure and conserved protein motifs. Many cis-acting regulatory elements related to the stress response were found in the promoter regions of these genes. In addition, a transcriptional analysis and qRT-PCR (quantitative reverse transcription PCR) showed that MsMsr genes show expression changes in response to abiotic stress in various tissues. Overall, our results suggest that MsMsr genes play an important role in the response to abiotic stress for alfalfa.

Background: Long-term care facilities (LTCFs) with compact, group-living arrangements have become COVID-19 hot spots during the pandemic. Systematic research is needed to understand factors associated with COVID-19 infections in LTCFs and the inadvertent effects of preventive measures adopted by LTCFs. Objectives: This rapid review identifies factors associated with LTCF residents’ COVID-19 infections and the impacts of the pandemic and the corresponding preventive measures on residents’ mental health and behavioral problems. Methods: Following the preferred reporting items for systematic reviews and meta-analyses guidelines, we identified and reviewed relevant literature in Medline, PsycINFO, and AgeLine. Results: Thirty-seven articles were identified and reviewed, including 30 reporting factors associated with COVID-19 infections in LTCFs and seven reporting the impact of the pandemic and corresponding prevention measures on LTCF residents. Results revealed four domains of factors associated with COVID-19 infections: facility physical environments, resident characteristics, facility management and testing, and community factors. The pandemic and infection control measures increased residents’ depression, anxiety, loneliness, and behavioral problems (e.g., agitation, hallucinations). Residents without cognitive impairments were more vulnerable to these adverse effects. Conclusion and implications: LTCF managers/policymakers and healthcare designers can help mitigate COVID-19 infections by (1) providing additional resources to vulnerable LTCFs; (2) enhancing the training of personal protective equipment use and guideline compliance; and (3) investing in amenities, such as sinks, quarantine rooms, and outdoor spaces. Digital activities and accessible green spaces can mitigate mental health and behavior issues. Future LTCF design can benefit from flexible spaces, natural ventilation, and reducing crowding.

This paper focuses on the leader-following consensus problem of discrete-time multi-agent systems subject to channel fading under switching topologies. First, a topology switching-based channel fading model is established to describe the information fading of the communication channel among agents, which also considers the channel fading from leader to follower and from follower to follower. It is more general than models in the existing literature that only consider follower-to-follower fading. For discrete multi-agent systems, the existing literature usually adopts time series or Markov process to characterize topology switching while ignoring the more general semi-Markov process. Based on the advantages and properties of semi-Markov processes, discrete semi-Markov jump processes are adopted to model network topology switching. Then, the semi-Markov kernel approach for handling discrete semi-Markov jumping systems is exploited and some novel sufficient conditions to ensure the leader-following mean square consensus of closed-loop systems are derived. Furthermore, the distributed consensus protocol is proposed by means of the stochastic Lyapunov stability theory so that the underlying systems can achieve ℋ∞ consensus performance index. In addition, the proposed method is extended to the scenario where the semi-Markov kernel of semi-Markov switching topologies is not completely accessible. Finally, a simulation example is given to verify the results proposed in this paper. Compared with the existing literature, the method in this paper is more effective and general.

Different concentrations (0, 1 mol%, 2 mol%, 6 mol% and 8 mol%) of palladium (Pd) nanoparticles modified hematite nanofibers (Pd NPs@ $\alpha $ -Fe2O3 NFs) were successfully synthesized via a facile electrospinning method followed by the calcination treatment. Their surface morphologies, crystal structures and chemical compositions were subsequently characterized in order to find optimum modification percentage. The gas sensing experiments on Pd NPs@ $\alpha $ -Fe2O3-based gas sensors revealed that encapsulation of Pd NPs into $\alpha $ -Fe2O3 NFs could significantly improve their sensing performances. Specifically, the as-prepared Pd4/Fe gas sensor exhibited higher response ( $\text{R}_{air}/\text{R}_{gas} =16.6$ ) toward 100 ppm acetone at 220°C, which was 3.4 times higher than that of Pd0/Fe sensor (4.89). Meanwhile, the Pd4/Fe sensor also showed shorter response/recovery (4 s/4 s), low limit of detection (LOD) (50 ppb) and good selectivity and long-term stability. The enhanced gas sensing properties of Pd NPs@ $\alpha $ -Fe2O3-based gas sensors could be attributed to the chemical and electronic sensitization of Pd NPs.

Actuator faults usually cause security problem in practice. This paper is concerned with the security control of positive semi-Markovian jump systems with actuator faults. The considered systems are with mode transition-dependent sojourn-time distributions, which may also lead to actuator faults. First, the time-varying and bounded transition rate that satisfies the mode transition-dependent sojourn-time distribution is considered. Then, a stochastic co-positive Lyapunov function is constructed. Using matrix decomposition technique, a set of state-feedback controllers for positive semi-Markovian jump systems with actuator faults are designed in terms of linear programming. Under the designed controllers, stochastic stabilization of the systems with actuator faults are achieved and the security of the systems can be guaranteed. Furthermore, the proposed results are extended to positive semi-Markovian jump systems with interval and polytopic uncertainties. By virtue of a segmentation technique of the transition rates, a less conservative security control design is also proposed. Finally, numerical examples are provided to demonstrate the validity of the presented results.

Investigating the release of organic pollutants from bricks made from solid waste is essential. Based on Fick's laws of diffusion, the diffusion model and diffusion-degradation model of polycyclic aromatic hydrocarbon (PAH) emission from the bricks were deduced. The degradation and 64-day emission of PAHs in solid bricks made of oil-based drill cuttings were observed experimentally. The emission and degradation characteristics of 14 PAHs were obtained and fitted with the diffusion and diffusion-degradation models. The emission of most of the PAHs from the bricks at the beginning was in good agreement with the diffusion model, except for benzo[a]anthracene, pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene. However, the emission of PAHs after some time was significantly lower than the theoretical value of the diffusion model. Moreover, fitting with the diffusion-degradation model gave better results, indicating that a joint diffusion-degradation mechanism controlled the emission of PAHs. Therefore, the diffusion-degradation model can better predict the long-term emission of PAHs in bricks made of oil-based drill cuttings.

Endotoxemia is mainly caused by a massive burst of inflammatory cytokines as a result of lipopolysaccharide (LPS) invasion. Chitooligosaccharides (COS) is expected to be a potential drug for relieving endotoxemia due to its anti-inflammatory properties. However, the structural parameters of COS are often ambiguous, and the effect of degree of acetylation (DA) of COS on its anti-inflammatory remains unknown. In this study, four COSs with different DAs (0%, 12%, 50% and 85%) and the same oligomers distribution were successfully obtained. Their structures were confirmed by 1H NMR and MS analysis. Then, the effect of DA on the anti-inflammatory activity and relieving endotoxemia potential of COS was researched. The results revealed that COS with a DA of 12% had better anti-inflammatory activity than COSs with other DAs, mainly in inhibiting LPS-induced inflammatory cytokines burst, down-regulating its mRNA expression and reducing phosphorylation of IκBα. Furthermore, this COS showed an obviously protective effect on endotoxemia mice, such as inhibiting the increase in inflammatory cytokines and transaminases, alleviating the injury of liver and intestinal tissue. This study explored the effect of DA on the anti-inflammatory activity of COS for the first time and lays the foundation for the development of COS as an anti-inflammatory drug against endotoxemia.

BiCuSeO oxyselenide, one of the best oxygen-containing thermoelectric materials, is promising with great potential applications. In this work, we present a high ZT of1.3 in Bi

International audience; This paper investigates the stability analysis and control design of a class of nonlinear positive Markovianjump systems with randomly occurring actuator faults and saturation. It is assumed that the actuator faults ofeach subsystem are varying and governed by a Markovian process. The nonlinear term is located in a sector.First, sufficient conditions for stochastic stability of the underlying systems are established using a stochasticco-positive Lyapunov function. Then, a family of reliable L1-gain controller is proposed for nonlinearpositive Markovian jump systems with actuator faults and saturation in terms of a matrix decompositiontechnique. Under the designed controllers, the closed-loop systems are positive and stochastically stablewith an L1-gain performance. An optimization method is presented to estimate the maximum domain ofattraction. Furthermore, the obtained results are developed for general Markovian jump systems. Finally,numerical examples are given to illustrate the effectiveness of the proposed techniques.

In this paper, an ultrahigh sensitive hydrazine electrochemical sensor based on gold nanoparticles integrated into a reduced graphene oxide/nickel foam (AuNPs-rGO@NF) hybrid structure was synthesized using a facile coating and electrochemical deposition method. The morphology and elemental composition of the as-synthesized AuNPs-rGO@NF structure was comprehensively investigated. Both cyclic voltammetry and potential amperometry results show the optimum AuNPs-rGO@NF sensor exhibits excellent electrochemical performances including higher sensitivity (14.635 μA μM−1 cm−2), lower limit of detection (0.056 μM; S/N = 3), wider linear detection range (0.2–200 μM), good selectivity and long-term stability. Meanwhile, the results of real sample analysis indicate the AuNPs-rGO@NF sensor has great potential for practical electrochemical hydrazine sensing applications.

Physical activity is a commonly prescribed medicine for people with conditions such as obesity and diabetes who are also at increased risk of being hospitalized or severely ill from COVID-19. However, many people are reporting challenges in engaging in a healthy dose of physical activity amid the pandemic.This rapid review synthesizes the current empirical evidence about the impacts of COVID-19 on people's outdoor physical activity and sedentary behavior while highlighting the role of community environments in promoting or hindering physical activity during the pandemic.Literature searches were conducted using keywords related to COVID-19: physical activity, mobility, and lifestyle behaviors. Eligibility criteria were peer-reviewed empirical and quantitative studies published in English, addressing COVID-19 and using physical activity and/or sedentary behavior as the study outcomes.Out of 61 eligible studies, the majority (78.3%) were conducted in Asian and European countries, with only four (6.7%) being US studies. The results showed that COVID-19 was linked with significant decreases in mobility, walking, and physical activity, and increases in sedentary activity. A few studies also reported contradicting results including increased uses of parks/trails and increased recreational activity among certain groups of population.Evidence suggests an overall negative impact of COVID-19 on physical activity, with differential effects across different sub-populations. Significant knowledge gaps are also found in the roles of social and physical attributes that can promote physical activity during pandemics with reduced safety risks.

Objectives Nursing homes (NHs) are important health care and residential environments for the growing number of frail older adults. The COVID-19 pandemic highlighted the vulnerability of NHs as they became COVID-19 hotspots. This study examines the associations of NH design with COVID-19 cases, deaths, and transmissibility and provides relevant design recommendations. Design A cross-sectional, nationwide study was conducted after combining multiple national data sets about NHs. Setting and Participants A total of 7785 NHs were included in the study, which represent 50.8% of all Medicare and/or Medicaid NH providers in the United States. Methods Zero-inflated negative binomial models were used to predict the total number of COVID-19 resident cases and deaths, separately. The basic reproduction number (R0) was calculated for each NH to reflect the transmissibility of COVID-19 among residents within the facility, and a linear regression model was estimated to predict log(R0 – 1). Predictors of these models included community factors and NHs’ resident characteristics, management and rating factors, and physical environmental features. Results Increased share of private rooms, larger living area per bed, and presence of a ventilator-dependent unit are significantly associated with reductions in COVID-19 cases, deaths, and transmissibility among residents. Increased number of certified beds in the NH is associated with reduced resident cases and deaths, after setting the number of actual residents as the exposure variable and controlling for staff cases. It also correlates with reduced transmissibility among residents when other risk factors, including staff cases, are controlled. Conclusions and Implications Architectural design attributes have significant impacts on COVID-19 transmissions in NHs. Considering the vulnerability of NH residents in congregated living environments, NHs will continue to be high-risk settings for infection outbreaks. To improve safety and resilience of NHs against future health disasters, facility guidelines and regulations should consider the need to increase private rooms and living areas.

The present study experimentally quantified the pyrolysis behaviors of waste solvent-based automotive paint sludge (OAPS) and water-based automotive paint sludge (WAPS) at four different heating rates using thermogravimetric-Fourier transform infrared (TG-FTIR) spectrometry and pyrolysis-gas chromatography-mass (Py-GC/MS) spectrometry analyses. Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods combined with the master-plots method were employed to investigate the pyrolysis kinetics and reaction mechanisms of waste automotive paint sludge. Three reaction stages and three reaction peaks in stage 2 were distinguished for both OAPS and WAPS degradation. The average activation energy (E

Au nanoparticle (Au NP) modified α-Fe2O3 nanodisk structures are obtained using a facile hydrothermal method and annealing based surface treatment. XRD, EDS, SEM, TEM and XPS are used to characterize the as-prepared samples, showing crystalline structured Au NPs of about 6–16 nm in diameter on the surface of α-Fe2O3 nanodisk structures of about 145 ± 15 nm in diameter. The Au NP modified α-Fe2O3 nanodisk structures are then investigated for acetone detection under different operating temperatures, showing improved gas sensing performance compared to the pure α-Fe2O3 nanomaterial. In particular, under the optimum working temperature (275 °C), the sensor response of Au0.5Fe can reach a sensibility of 19.5 toward 100 ppm acetone, which is about two times higher than that of the pure one. Meanwhile, the Au0.5Fe acetone sensor also exhibits fast response and recovery time (4 s/7 s), good linear relationship (50–5000 ppb), low detection limit (50 ppb), excellent long-term stability and superior selectivity. Finally, the enhanced gas sensing mechanism of Au NP modified α-Fe2O3 nanomaterials can be attributed to the combined action of chemical and electronic sensitization of Au NPs, which are promising as highly sensing materials toward acetone detection.

Corynebacterium pseudotuberculosis (CP) infection in livestock has become highly difficult to control. To decrease the incidence of CP infection, the supplementation of feed with non-antibiotic antibacterial substances is a potential approach. The aim of this study was to assess the effects of sodium butyrate (NaB), a potential alternative to antibiotics, on CP infection in RAW264.7 macrophages and C57BL/6 mice. Our data showed that NaB (2 mM) significantly ameliorated CPinfection in RAW264.7 macrophages and decreased the bacterial load in the spleens of infected mice. By real-time PCR, we found that NaB induced significant decreases in zinc-dependent superoxide dismutase (sodC) and tip protein C (spaC) expression in CP from infected-RAW264.7 cells and in phospholipase D (pld) and spaC expression in CP from the spleens of infected mice. NaB treatment significantly up-regulated cathelicidin-related antimicrobial peptide (cramp) expression in spleens of mice infected with CP. Furthermore, NaB alleviated histopathological changes in spleens of CP-infected mice. In conclusion, NaB ameliorated CP infection in RAW264.7 macrophages and C57BL/6 mice, and these effects may be related to the modulation of sodC, spaC, pld, and cramp expression.

This paper proposes the robust model predictive control of positive time-delay systems with interval and polytopic uncertainties, respectively. The model predictive control framework consists of linear constraint, linear performance index, linear Lyapunov function, linear programming algorithm, and cone invariant set. By virtue of matrix decomposition technique, robust model predictive controllers of interval and polytopic positive systems with multiple state delays are designed, respectively. A multi step control strategy is utilized and a cone invariant set is constructed. Linear programming is used for the corresponding MPC conditions. Finally, a numerical example is given to verify the effectiveness of the proposed design.

Sphene–titanium oxide composite coatings are prepared by a hybrid technique of microarc oxidation (MAO) and heat treatment on titanium. The average roughness of the MAO coating increases after heat treatment due to the crystallization and crystal growth of the MAO coating. The wetting ability, roughness, phase composition and surface topological structure of the composite coatings have positive effects on the MC3T3-E1 cell attachment, proliferation and alkaline phosphatase activity. The composite coatings do not cause any hemolysis effect. Furthermore, they also do not give rise to any adverse reactions in vivo according to micro-CT images, radiographs and histological analysis. At the same time, the sphene–titanium oxide composite coatings show perfect osseointegration in rabbit tibia in vivo and display the higher interface bonding strength with rabbit tibia compared to the MAO coating without heat treatment, because the composite coatings have higher bioactivity, good cell response and mechanical properties, and so on.

The Corynebacterium pseudotuberculosis, a gram-positive facultative intracellular bacteria, usually resulted in covert but huge economic losses in goats and sheep industry. Limited information is available rewardingly in southwestern China, one of the most important regions for goats production. This study reported for the first time the isolation and molecular characteristics of C. pseudotuberculosis from external abscess of goats in southwestern China, and found that (1) the isolation rate of C. pseudotuberculosis in abscess of goats was 39.22% (40/102), (2) all of isolated strains were sensitive to vancomycin, norfloxacin, cefradine, clarithromycin and cefepime, but resistant to nitrofurantoin and furazolidone, (3) the virulence or putative virulence genes including PLD, FagA, FagB, FagC, FagD, SigE, SpaC, SodC, PknG, NanH, OppA, OppB, OppC, OppD, OppF, CopC, NrdH and CpaE were presented in all C. pseudotuberculosis strains, (4) the housekeeping gene fusA can effectively differentiate biovar ovis from biovar equi in phylogenic analysis and can be employed for further epidemiological study of C. pseudotuberculosis. Briefly, this study provided the basic information for infection of C. pseudotuberculosis in goats and will help in controlling of this pathogen in southwestern China.

This paper addresses the model predictive control for positive systems with uncertainty and exogenous disturbance input. By utilizing a linear Lyapunov function, a sequence of model predictive controllers for positive systems is designed based on multi-step control sets guaranteeing robust stability with mixed performances. A sequence of cone sets is chosen as the invariant sets of the model predictive control. With the above idea, a model predictive control algorithm is established to compute the optimal value of the mixed performances. All conditions are in terms of linear programming to cope with large-scale computation with low computation burden. Finally, a numerical example is provided to verify the effectiveness of the proposed design.

Corynebacterium pseudotuberculosis is a prominent human and animal pathogen causing chronic inflammatory diseases. Interleukin-1β (IL-1β) is involved in the response to such pathogenic infections. However, the mechanism by which IL-1β is secreted during C. pseudotuberculosis infection remains unclear. This study aimed to investigate the mechanism underlying IL-1β secretion by macrophages infected with C. pseudotuberculosis. Herein, we firstly revealed that nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC) and caspase-1 (Casp1) play critical roles in IL-1β secretion rather than IL-1β precursor (pro-IL-1β) expression in C. pseudotuberculosis-infected macrophages. Toll like receptor 4 (TLR4) is partially involved in IL-1β secretion, while absent in melanoma 2 (AIM2) is not involved in IL-1β secretion by C. pseudotuberculosis-infected macrophages. In addition, nuclear factor kappa B (NF-κB) and p38 mitogen-activated protein kinases (p38 MAPK) inhibitors almost attenuated IL-1β secretion, implying that NF-κB and p38MAPK pathway are involved in IL-1β secretion in C. pseudotuberculosis-infected macrophages. Furthermore, C. pseudotuberculosis were significantly more numerous in Nlrp3-/-, Asc-/-, and Casp-1-/- macrophages than in WT macrophages at 24 h after infection (P < 0.05), indicating that NLRP3 inflammasome components limit C. pseudotuberculosis replication in macrophages. Together, these data provide novel insights into the mechanisms underlying IL-1β secretion in C. pseudotuberculosis-infected macrophages and further the current understanding of the host pro-inflammatory immune response against this pathogen.

We first review the literature on machine behavior which may contain the interaction between machines, and then discuss the methodology and the related case involving collaboration between robots to instantiate the concept with AI empowerment. The navigation case aims to a security application with autonomous control and roadside agent embedded in a mobile edge computing structure. In the studied navigation based on the artificial potential field method, robots need to use position information to calculate the moving direction frequently. In the case of high motion speed as well as GPS positioning error, the path trajectory may show a sharp change of direction. In order to mitigate the trajectory oscillation, this paper proposes a path planning design where training process and motion direction prediction are integrated by using artificial neural network. The auxiliary navigation agent near multiple obstacles can first extract the past movement information of the robot and then determines whether there is a serious path jitter event. Computer simulation analysis shows that the combination of autonomous control and cooperative behavior can effectively reduce the path jitter so as to achieve a fast and safe path planning.

An efficient technique to fabricate BiCuSeO oxyselenides thermoelectric bulks is studied. Pb doped p-type BiCuSeO ingots are synthesized by microwave processing for 4 minutes and the bulk materials with 8.7~8.9 gcm−3 density are produced after spark plasma sintering for 5 minutes. The XRD and XPS detection results show that all the samples have nearly a single phase indexed to tetragonal BiCuSeO, and the peak positions of Pb 4f7/2 and 4f5/2 simple spin-orbit doublet peaks in Bi0.98Pb0.02CuSeO and Bi0.90Pb0.10CuSeO respectively are 137.93 and 142.76 eV, and 137.49 and 142.49 eV. Holes are the majority carriers with concentrations of 3.22 1020cm−³ ~2.40 1021cm−³ in the doped samples. Bi0.98Pb0.02CuSeO shows the highest ZT of 0.76 at 773 K and possible larger values can be achieved at a higher temperature. The fabricate technique described here showing great prospect in the research and manufacturing of thermoelectric bulks.

Parallel plate actuators (PPAs) are widely used actuators in microelectromechanical systems. A PPA can be utilised as a passive/active vibration isolator. A novel active vibration isolator with a simple structure, which requires a constant voltage source and series capacitor, is proposed. The principle of the spring softening effect is analysed, which can avoid a specific external disturbance by changing its resonant frequency. A simulation study was performed to verify the feasibility of this type of isolator.