A Robust, Flexible, Hydrophobic, and Multifunctional Pressure Sensor Based on an MXene/Aramid Nanofiber (ANF) Aerogel Film.

Pressure sensors with desirable flexibility, robustness, and versatility are urgently needed for complicated smart wearable devices. However, developing an ideal multifunctional flexible sensor is still challenging. In this work, a composite aerogel film sensor with an internal three-dimensional (3D) microporous and hierarchical structure is successfully fabricated by the self-assembly of aramid nanofiber (ANF) and conductive MXene by vacuum-assisted filtration and ice crystal growth. The resultant MXene/ANF aerogel film with a mass ratio of 3/7 (30% MAAF) presents high robustness with an outstanding tensile strength of 14.1 MPa and a modulus of 455 MPa while retaining appealing flexibility and sensitive characteristics due to the 3D microstructure. Accompanied by superior electric conductivity, the MAAF sensor performs noticeably in human motion and microexpression detection with a fast response time of 100 ms and a high sensitivity of 37.4 kPa-1. In addition, MAAF exhibits considerable thermal shielding performance based on the excellent thermostability. Moreover, it possesses prominent electrothermal property with a wide heating temperature range (32.7-242 °C) in a fast thermal response time (5 s) due to the Joule effect. Additionally, a hydrophobic SiO2 coating is introduced on the surface of MAAF to further broaden the sensing application, and the obtained MAAF@SiO2 sensor shows distinguished sensing capability underwater, which can be accurately applied to swimming monitoring. Therefore, this work provides a highly flexible, lightweight, robust, and multifunctional aerogel film sensor, showing promising potential in smart wearable sensing and healthcare devices, intelligent robots, and underwater detection.

Theoretical and Experimental Studies of Micro-Surface Crack Detections Based on BOTDA.

Micro-surface crack detection is important for the health monitoring of civil structures. The present literature review shows that micro-surface cracks can be detected by the Brillouin scattering process in optical fibers. However, the existing reports focus on experiment research. The comparison between theory and experiment for Brillouin-scattering-based optical sensors is rarely reported. In this paper, a distributed optical fiber sensor for monitoring micro-surface cracks is presented and demonstrated. In the simulation, by using finite element methods, an assemblage of a three-dimensional beam model for Brillouin optical time domain analysis (BOTDA) was built. The change in Brillouin frequency (distributed strain) as a function of different cracks was numerically investigated. Simulation results indicate that the amplitudes of the Brillouin peak increase from 27 µÎµ to 140 µÎµ when the crack opening displacement (COD) is enlarged from 0.002 mm to 0.009 mm. The experiment program was designed to evaluate the cracks in a beam with the length of 15 m. Experimental results indicate that it is possible to detect the COD in the length of 0.002~0.009 mm, which is consistent with the simulation data. The limitations of the proposed sensing method are discussed, and the future research direction is prospected.

Understanding the Impact of Environmentally Specific Servant Leadership on Employees' Pro-Environmental Behaviors in the Workplace: Based on the Proactive Motivation Model.

The increasingly severe environmental situation has brought challenges to the world, and organizations are aware of the importance of environmental management and are committed to changing individuals' environmental behavior patterns. Based on the proactive motivation model, this study constructs a moderated multiple mediation model to explore the impact mechanism and boundary conditions between environmentally specific servant leadership (ESSL) and employees' workplace pro-environmental behaviors (WPB). This study examines 440 Chinese industrial sector employees, and the linear regression method test results show that: (1) ESSL significantly promotes employees' WPB. (2) Green self-efficacy (GSE), green organizational identity (GOI), and environmental passion (EP) act as multiple mediators between ESSL and employees' WPB. (3) Green shared vision (GSV) positively moderates the relationship between ESSL and employees' WPB. This study provides a new theoretical perspective on how ESSL affects employees' WPB, which is analyzed from three aspects: "can do", "reason to", and "energized to". This new mechanism reveals that leaders should transform their leadership style to that of environmental service, and focus on enhancing the employees' GSE, GOI, and EP. Moreover, ESSL should make copious use of green strategy tools, such as GSV, to realize the above mechanism.

Innovation and environmental total factor productivity in China: the moderating roles of economic policy uncertainty and marketization process.

China's economic development practices are facing strict energy constraints and severe environmental pollution. Improvement of China's environmental total factor productivity (ETFP) through innovation is a major scientific focus of both policy-makers and academia. However, the boundary conditions where innovation affects ETFP are yet to be clarified. On this basis, the present study starts from two dimensions-policy context and market context, introduces economic policy uncertainty (EPU) and marketization process as moderating variables, and examines the impact mechanism of innovation on ETFP. The results show the following: (1) Innovation promotes ETFP. (2) Although EPU inhibits ETFP, it positively moderates the impact of innovation on ETFP. (3) The marketization process has an insignificant inhibitory effect on ETFP. Specifically, the development of product markets, the development of market intermediary organizations, and the legal system environment have a significant inhibitory effect on ETFP. In contrast, the marketization process positively moderates the impact of innovation on ETFP. (4) The impact of innovation on ETFP exhibits obvious regional heterogeneity. In regions with low pollution intensity, innovation and EPU promotes ETFP. The marketization process inhibits ETFP and shows a positive moderating effect. In regions with high pollution intensity, both innovation and EPU inhibits ETFP. Based on these conclusions, policy-makers should guide companies to increase investment in research and development, improve innovation capabilities, and focus on strengthening energy-saving and environmental protection technologies and process innovations. When formulating and adjusting economic policies, policy-makers should aim promote enterprise innovation and reduce the negative impact of economic policy uncertainty. Policies should fully utilize the decisive role of the market in the allocation of innovative factors and rely on market mechanisms to enhance the positive effect of innovation on regional ETFP.

Effectiveness-based innovation or efficiency-based innovation? Trade-off and antecedents under the goal of ecological total-factor energy efficiency in China.

Pursuing innovation effect or efficiency is an important trade-off that Chinese local governments need to face in the process of developing economy and protecting the environment. From the perspective of the policy portfolio, we employ the industrial panel data of 30 provinces in China during 2000-2015 to analyze the impacts of effectiveness-based innovation and efficiency-based innovation on ecological total-factor energy efficiency (ETFEE), and further analyze the effects of command-and-control, market-based and voluntary environmental regulations on innovation. The findings reveal that (1) both effectiveness-based innovation and efficiency-based innovation have significant promoting effects on ETFEE. (2) Three types of environmental regulations have significantly inhibitory effects on effectiveness-based innovation and efficiency-based innovation. (3) The interaction term of command-and-control and market-based regulations plays a significant role in promoting effectiveness-based innovation and efficiency-based innovation, whereas the interaction term of market-based and voluntary regulations merely promotes efficiency-based innovation. The interaction term of three types of regulation only has a synergetic and positive effect on the efficiency-based innovation. Finally, this paper gives specific policy recommendations.

Gut Barrier Dysfunction Induced by Aggressive Fluid Resuscitation in Severe Acute Pancreatitis is Alleviated by Necroptosis Inhibition in Rats.

Fluid resuscitation is the first-line antishock treatment in severe acute pancreatitis (SAP). Currently, although mentions of complications related to aggressive fluid resuscitation are very frequent, a lack of proper handling of complications remains. One of the most important complications is intestinal barrier injury, including intestinal ischemia-reperfusion injury following aggressive fluid resuscitation. Once injured, the intestinal barrier may serve as the source of additional diseases, including systemic inflammatory response syndrome and multiple organ dysfunction syndrome, which aggravate SAP. This study focused on the underlying mechanisms of gut barrier dysfunction in rats induced by aggressive fluid resuscitation in SAP. This study further indicated the important role of necroptosis in intestinal barrier injury which could be relieved by using necroptosis-specific inhibitor Nec-1 before aggressive fluid resuscitation, thus reducing intestinal barrier damage. We also found pancreas damage after intestinal ischemia/reperfusion challenge and indicated the effects of high mobility group protein B1 in the vicious cycle between SAP and intestinal barrier damage.

Research on tunable distributed SPR sensor based on bimetal film.

In order to overcome the limitations in range of traditional prism structure surface plasmon resonance (SPR) single-point sensor measurement, a symmetric bimetallic film SPR multi-sensor structure is proposed. Based on this, the dual-channel sensing attenuation mechanism of SPR in gold and silver composite film and the improvement of sensing characteristics were studied. By optimizing the characteristics such as material and thickness, a wider range of dual-channel distributed sensing is realized. Using a He-Ne laser (632.8 nm) as the reference light source, prism-excited symmetric SPR sensing was studied theoretically for a symmetrical metal-clad dielectric waveguide using thin-film optics theory. The influence of the angle of incidence of the light source and the thickness of the dielectric layer on the performance of SPR dual formant sensing is explained. The finite-difference time-domain method was used for the simulation calculation for various thicknesses and compositions of the symmetric combined layer, resulting in the choice of silver (30 nm) and gold (10 nm). When the incident angle was 78 deg, the quality factor reached 5960, showing an excellent resonance sensing effect. The sensitivity reached a maximum of 5.25×10-5 RIU when testing the water content of an aqueous solution of honey, which proves the feasibility and practicality of the structure design. The structure improves the theoretical basis for designing an SPR multi-channel distributed sensing system, which can greatly reduce the cost of biochemical detection and significantly increase the detection efficiency.

Targeting intestinal epithelial cell-programmed necrosis alleviates tissue injury after intestinal ischemia/reperfusion in rats.

BACKGROUND: Intestinal dysfunction, especially acute pathologies linked to intestinal ischemia/reperfusion (I/R) injury, is profoundly affected by inflammation and improper execution of cell death. Few studies have examined the efficacy of combined strategies in regulated intestinal epithelial necrosis after intestinal I/R. Here, we evaluated the functional interaction between poly (adenosine diphosphate-ribose) polymerase 1 (PARP-1)-induced parthanatos and receptor-interacting protein 1/3 (RIP1/3) kinase-induced necroptosis in the pathophysiological course of acute ischemic intestinal injury. METHODS: Anesthetized adult male Sprague-Dawley rats were subjected to superior mesenteric artery occlusion consisting of 1.5 h of ischemia and 6 h of reperfusion. The PARP-1-specific inhibitor PJ34 (10 mg/kg) and the RIP1-specific inhibitor Necrostatin-1 (1 mg/kg) were intraperitoneally administered 30 min before the induction of ischemia. RESULTS: Intestinal I/R was found to result in PARP-1 activation and RIP1/3-mediated necrosome formation. PJ34 or Necrostatin-1 treatment significantly improved the mucosal injury, while the combined inhibition of PARP-1 and RIP1/3 conferred optimal protection of the intestine. Meanwhile, results from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling assay showed a decrease in intestinal epithelial cell death. Interestingly, we further showed that PARP-1 might act as a downstream signaling molecule of RIP1 in the process of I/R-induced intestinal injury and that the RIP1/PARP-1-dependent cell death signaling pathway functioned independently of caspase 3 inhibition. CONCLUSIONS: The results of our study provide a molecular basis for combination therapy that targets both pathways of regulated necrosis (parthanatos and necroptosis), to treat acute intestinal I/R-induced intestinal epithelial barrier disruption.

Recent advances on the thermal destabilization of Mg-based hydrogen storage materials.

Magnesium hydride and its compounds have a high hydrogen storage capacity and are inexpensive, and thus have been considered as one of the most promising hydrogen storage materials for on-board applications. Nevertheless, Mg/MgH2 systems suffer from great drawbacks in terms of kinetics and thermodynamics for hydrogen uptake/release. Over the past decades, although significant progress has been achieved with respect to hydrogen sorption kinetics in Mg/MgH2 systems, their high thermal stability remains the main drawback, which hinders their practical applications. Accordingly, herein, we present a brief summary of the synthetic routes and a comprehensive overview of the advantages and disadvantages of the promising strategies to effectively tune the thermodynamics of Mg-based materials, such as alloying, nanostructuring, metastable phase formation, changing reaction pathway, and nano Mg-based composites. Among them nanostructuring and metastable phase formation, which have the superiority of changing the thermodynamics without affecting the hydrogen capacity, have attracted increasing interest in this field. To further optimize the hydrogen storage performance, we specially emphasize novel nanostructured materials, which have the advantage of combining alloy engineering, nanostructuring and the synergistic effect to change the thermodynamics of Mg/MgH2 to some extent. Furthermore, the remaining challenges and the directions of further research on MgH2, including the fundamental mechanism of the Mg-H bond instability, advanced synthetic routes, stabilizing nanostructures, and predicting novel composite materials, are proposed.

Lithium Treatment Prevents Apoptosis in Neonatal Rat Hippocampus Resulting from Sevoflurane Exposure.

We aimed to observe the therapeutic effects of lithium on inhalational anesthetic sevoflurane-induced apoptosis in immature brain hippocampus. From postnatal day 5 (P5) to P28, male Sprague-Dawley pups were intraperitoneally injected with lithium chloride or 0.9 % sodium chloride. On P7 after the injection, pups were exposed to 2.3 % sevoflurane or air for 6 h. Brain tissues were harvested 12 h and 3 weeks after exposure. Cleaved caspase-3, nNOS protein, GSK-3ß,p-GSK-3ß were assessed by Western blot, and histopathological changes were assessed using Nissl stain and TUNEL stain. From P28, we used the eight-arm radial maze test and step-through test to evaluate the influence of sevoflurane exposure on the learning and memory of juvenile rats. The results showed that neonatal sevoflurane exposure induced caspase-3 activation and histopathological changes in hippocampus can be attenuated by lithium chloride. Sevoflurane increased GSK-3ß activity while pretreatment of lithium decreased GSK-3ß activity. Moreover, sevoflurane showed possibly slight but temporal influence on the spatial learning and the memory of juvenile rats, and chronic use of lithium chloride might have the therapeutic effect. Our current study suggests that lithium attenuates sevoflurane induced neonatal hippocampual damage by GSK-3ß pathway and might improve learning and memory deficits in rats after neonatal exposure.

Sevoflurane-induced down-regulation of hippocampal oxytocin and arginine vasopressin impairs juvenile social behavioral abilities.

Cumulative evidence indicates that early childhood anesthesia can alter a child's future behavioral performance. Animal researchers have found that sevoflurane, the most commonly used anesthetic for children, can produce damage in the neonatal brains of rodents. To further investigate this phenomenon, we focused on the influence of sevoflurane anesthesia on the development of juvenile social behavioral abilities and the pro-social proteins oxytocin (OT) and arginine vasopressin (AVP) in the neonatal hippocampus. A single 6-h sevoflurane exposure for postnatal day 5 mice resulted in decreased OT and AVP messenger RNA (mRNA) and protein levels in the hippocampus. OT and AVP proteins became sparsely distributed in the dorsal hippocampus after the exposure to sevoflurane. Compared with the air-treated group, mice in the sevoflurane-treated group showed signs of impairment in social recognition memory formation and social discrimination ability. Sevoflurane anesthesia reduces OT and AVP activities in the neonatal hippocampus and impairs social recognition memory formation and social discrimination ability in juvenile mice.

Proteomic analysis of intestinal ischemia/reperfusion injury and ischemic preconditioning in rats reveals the protective role of aldose reductase.

Intestinal ischemia/reperfusion (I/R) injury is a critical condition associated with high morbidity and mortality. Studies show that ischemic preconditioning (IPC) can protect the intestine from I/R injury. However, the underlying molecular mechanisms of this event have not been fully elucidated. In the present study, 2-DE combined with MALDI-MS was employed to analyze intestinal mucosa proteomes of rat subjected to I/R injury in the absence or presence of IPC pretreatment. The protein content of 16 proteins in the intestinal mucosa changed more than 1.5-fold following intestinal I/R. These proteins were, respectively, involved in the cellular processes of energy metabolism, anti-oxidation and anti-apoptosis. One of these proteins, aldose reductase (AR), removes reactive oxygen species. In support of the 2-DE results, the mRNA and protein expressions of AR were significantly downregulated upon I/R injury and enhanced by IPC as confirmed by RT-PCR and western blot analysis. Further study showed that AR-selective inhibitor epalrestat totally turned over the protective effect of IPC, indicating that IPC confers protection against intestinal I/R injury primarily by increasing intestinal AR expression. The finding that AR may play a key in intestinal ischemic protection might offer evidences to foster the development of new therapies against intestinal I/R injury.

[Detecting the haplotype of three Y-STR loci by fluorescent multiplex amplification].

OBJECTIVE: To establish a fluorescent multiplex PCR system for typing Y-STR loci Y-GATA-A7.1, DYS456 and DYS443, and investigate their haplotype frequencies in Chinese Han population. METHODS: 203 unrelated males of Han population living in Zhengzhou were typed by fluorescent multiplex amplification system and ABI 3100 genetic analyzer. RESULTS: In Zhengzhou Han population, 5,6 and 6 different alleles were observed for Y-GATA-A7.1, DYS456 and DYS443 loci, and their gene diversity (GD) were 0.669 2, 0.583 9 and 0.705 3 respectively. A total of 44 different haplotypes formed by these three loci was identified and the haplotype diversity (HD) reached 0.952 3. CONCLUSION: The fluorescent multiplex system for these three Y-STR loci will be very powerful for forensic individual identification and paternity testing in Chinese Han population.