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Cathodic electrochemiluminescence (ECL) of a luminol (or its analogues)-dissolved oxygen (O2) system is an ideal alternative to ECL of the traditional luminol–hydrogen peroxide (H2O2) system, which can efficiently avoid the self-decomposition of H2O2 at room temperature. However, the mechanism for the generation of cathodic ECL by the luminol (or its analogues)–O2 system is still ambiguous. Herein, we report the study of cathodic ECL generation by the L012–O2 system at a glassy carbon electrode (GCE). The types of reactive oxygen species (ROS) involved generated during ECL reactions were verified. A possible reaction mechanism for the system was proposed and the rate constants of related reactions were estimated. Furthermore, several intermediates of L012 involved in the proposed pathways were validated by electrochemistry-coupled mass spectrometry. Finally, the cathodic ECL system was successfully used for measuring the antioxidant capacity of commercial juice with Trolox as a standard. [ABSTRACT FROM AUTHOR]

A multi-material active structure is a mechanical system made of passive and active materials with the ability to alter its configuration, form, or properties in response to changes in the environment. Active structures have been investigated to design lightweight structures and structures with the ability to “smartly” alter their shapes and/or internal forces. Recently, the potential of active structures to reduce environmental impact, i.e., reduce energy consumption and greenhouse gas (GHG) emissions, has been investigated. It has been verified that, compared to passive structures, active structures can not only use less material but also consume less energy and cause less GHG emissions during their service life, and thus have a significant potential to be applied as environment-friendly mechanical structures. This study aims to develop a general topology optimization (TO) approach to design novel multi-material active structural systems to reduce environmental impact. The approach is based on the density-based TO scheme. Passive and active materials are considered in the TO process and are required to be optimally distributed according to the optimization objective and constraints. The energy consumption or GHG emissions caused by the structure during its service life are treated as the objective function to be minimized under multiple displacement requirements. Typical examples are carried out to verify the developed approach. Results show that the topology optimized active structures may not only achieve significant weight savings but also less energy consumption and GHG emissions compared to equivalent topology optimized passive structures, which indicates that the developed approach has the potential to be applied to design novel structural systems with lighter weight, larger span, and with less environmental impact compared to conventional passive structural systems. [ABSTRACT FROM AUTHOR]

This study develops stability conditions for general tensegrity regarding the three stability criteria (e.g., prestress stability, general stability, and super stability) based on an energy approach. The coupling relations of specific nodal degrees of freedom caused by the rigid bodies are described by a set of constraint functions and incorporated into the potential energy function by the Lagrangian multiplier method. Stiffness matrices of general tensegrity systems are derived from the augmented potential energy function. It shows that the stability of general tensegrity can be evaluated through the stiffness matrices expressed in the constrained motion space generated by the constraint functions. Elegant formulations are developed for the evaluation of the three types of stability conditions for general tensegrity systems. Moreover, it turns out that the formulations developed in this study will degenerate into those for the stability analysis of classic tensegrity if no rigid bodies exist in the system, which indicates that the proposed approach is a general framework for the stability analysis of any type of tensegrity systems. [ABSTRACT FROM AUTHOR]

In a ZnO microcavity, the exciton-polariton effect with ultralarge Rabi splitting (can be as large as several hundreds of millielectron volts) may dominate the optical properties at the energies near the band edge. Due to the light-matter coupling, the renormalized energy states, i.e., the exciton-polariton states are expected to show very different dynamical behavior compared to the free exciton state. In this work, we used a femtosecond laser to pump a high-quality ZnO whispering gallery microcavity at room temperature. In the time-resolved photoluminescence measurements, we observed that both the fast and slow decay rates of the exciton-polaritons are faster than that of the free exciton due to the strong coupling between excitons and photons in a microcavity. The decay time constants are found to depend on the exciton-photon energy detuning (δ = E p h o t o n − E e x c i t o n ). [ABSTRACT FROM AUTHOR]

Herein we report the study of electrochemiluminescence (ECL) generation by tris(2,2′‐bipyridyl)ruthenium (Ru(bpy)32+) and five tertiary amine coreactants. The ECL distance and lifetime of coreactant radical cations were measured by ECL self‐interference spectroscopy. And the reactivity of coreactants was quantitatively evaluated in terms of integrated ECL intensity. By statistical analysis of ECL images of single Ru(bpy)32+‐labeled microbeads, we propose that ECL distance and reactivity of coreactant codetermine the emission intensity and thus the sensitivity of immunoassay. 2,2‐bis(hydroxymethyl)‐2,2′,2′′‐nitrilotriethanol (BIS‐TRIS) can well balance ECL distance‐reactivity trade‐off and enhance the sensitivity by 236 % compared with tri‐n‐propylamine (TPrA) in the bead‐based immunoassay of carcinoembryonic antigen. The study brings an insightful understanding of ECL generation in bead‐based immunoassay and a way of maximizing the analytical sensitivity from the aspect of coreactant. [ABSTRACT FROM AUTHOR]

Herein we report the study of electrochemiluminescence (ECL) generation by tris(2,2′‐bipyridyl)ruthenium (Ru(bpy)32+) and five tertiary amine coreactants. The ECL distance and lifetime of coreactant radical cations were measured by ECL self‐interference spectroscopy. And the reactivity of coreactants was quantitatively evaluated in terms of integrated ECL intensity. By statistical analysis of ECL images of single Ru(bpy)32+‐labeled microbeads, we propose that ECL distance and reactivity of coreactant codetermine the emission intensity and thus the sensitivity of immunoassay. 2,2‐bis(hydroxymethyl)‐2,2′,2′′‐nitrilotriethanol (BIS‐TRIS) can well balance ECL distance‐reactivity trade‐off and enhance the sensitivity by 236 % compared with tri‐n‐propylamine (TPrA) in the bead‐based immunoassay of carcinoembryonic antigen. The study brings an insightful understanding of ECL generation in bead‐based immunoassay and a way of maximizing the analytical sensitivity from the aspect of coreactant. [ABSTRACT FROM AUTHOR]

Antibiotic resistance is one of the most significant issues encountered in global health. There is an urgent demand for the development of a new generation of antibiotic agents combating the emergence of drug resistance. In this article, we reported the design of lipidated dendrimeric γ-AApeptides as a new class of antimicrobial agents. These AApeptides showed excellent potency and broad-spectrum activity against both Gram-positive bacteria and Gram-negative bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). The mechanistic studies revealed that the dendrimeric AApeptides could kill bacteria rapidly through the permeabilization of bacterial membranes, analogous to host-defense peptides (HDPs). These dendrimers also did not induce antibiotic resistance readily. The easy access to the synthesis, together with their potent and broad-spectrum activity, make these lipidated dendrimeric γ-AApeptides a new generation of antibacterial agents. [ABSTRACT FROM AUTHOR]

Purpose: Previous studies showed that peroxisome proliferator-activated receptor gamma (PPARγ) and PPARγ coactivator1 family (PPARGC1A and PPARGC1B) gene single nucleotide variants (SNVs)were strongly associated with cancer susceptibility. The purpose of this study was to investigate the association of PPARγ, PPARGC1A, and PPARGC1B variants with the risk of gastric cancer (GC). Patients and methods: We performed a case-control study of 490 GC cases and 1,476 healthy controls from eastern China. PPARγ rs1801282 C > G, rs3856806 C > T, PPARGC1A rs2970847 C > T, rs8192678 C > T and PPARGC1B rs7732671 G > C, rs17572019 G > A SNVs were selected to investigate the association between these SNVs and GC susceptibility. Genotypes of the SNVs were assessed by multiplex fluorescent PCR using a custom-by-design 48-Plex SNPscantm Kit. Results: The PPARγ rs1801282 SNV was associated with a decreased risk for GC (GC vs. CC: odds ratio (OR) = 0.62, 95% confidence interval (95%CI) = 0.42–0.93, adjusted P = 0.019; GC + GG vs. GG: OR = 0.63 95%CI = 0.42–0.93, adjusted P = 0.019; respectively). In addition, stratified analysis revealed that the PPARγ rs1801282 SNV was correlated with the risk of GC in subgroups of age ≥ 61, no smoking, and no alcohol consuming. We also confirmed that the PPARγ rs3856806 C > T SNV promoted the risk of GC in women. The PPARGC1A rs8192678 TT genotype decreased the susceptibility of GC in men. The PPARGC1A rs2970847 C > T SNV decreased the susceptibility of GC in the subgroup of BMI ≥ 24 kg/m2. The PPARGC1B rs7732671 G > C and rs17572019 G > A SNVs promoted the risk of GC in the subgroup of BMI ≥ 24 kg/m2. Conclusion: This study indicates that the PPARγ, PPARGC1A, and PPARGC1B SNVs may be associated with the susceptibility of GC in eastern Chinese population. Future studies with larger populations, detailed H. pylori infection status for subgroup analysis, and functional study are needed to further clarify the relationship between these SNVs and GC risk. [ABSTRACT FROM AUTHOR]

Engineering failure investigations seek to reconstruct the actual causes of major engineering failures. The investigators need to establish the existence of certain past events and the actual causal relationships that these events bear to the failures in question. In this paper, I examine one method for reconstructing the actual causes of failure events, which I call "feature dependence". The basic idea of feature dependence is that some features of an event are informative about the features of its causes; therefore, the investigators can use the features of a known failure event to reconstruct details of its causes. I make explicit the structure of feature dependence and the evidential basis of its key premises, and show how feature dependence works in the investigation of the American Airlines Flight 191 accident. [ABSTRACT FROM AUTHOR]

The ionospheric delay is one of the important error sources in the Global Navigation Satellite System (GNSS) data processing. With the rapid construction and development of GNSS, the abundant satellite resources have brought new opportunities for ionospheric monitoring. To further investigate the performances and abilities of Galileo and BDS in ionosphere modeling, we study the ionosphere modeling based on the 15th order spherical harmonic function, and 364 stations around the world are selected for global ionospheric modeling of GPS, GLONASS, Galileo and BDS systems under ionospheric quiet and active conditions, respectively. The results show that the average biases of the ionospheric models built by GPS, GLONASS and Galileo are relatively small, which are within 2 Total Electron Content Unit (TECU) as compared to the Center for Orbit Determination in Europe (CODE) global ionospheric map (GIM), while the average biases of the models built by BDS are between 6 and 8 TECU during the ionospheric quiet and active days, respectively. In addition, in order to analyze the modeling performances before and after using BDS geostationary earth orbit (GEO) satellites, BDS is divided into two groups, in which one group contains medium earth orbit (MEO), inclined geosynchronous orbit (IGSO) and GEO satellites; and the other group contains only MEO and IGSO satellites. The results show that the influence of GEO satellites on ionospheric modeling is less than 1 TECU. Due to the distribution of the stations, the 0-value region in the ionospheric model is mainly distributed in the mid and high-latitude regions of the southern hemisphere. Since the ionospheric parameters are lumped with the Differential Code Bias (DCB), we also estimate the DCB parameters and analyze their performances. The DCB estimated in ionosphere modeling shows strong stability, with the average biases of GPS, GLONASS, Galileo and BDS under 0.25 ns, 0.25 ns, 0.2 ns and 0.42 ns, respectively. We also estimate other DCB types of the four GNSS systems. The results show that the DCB is stable and shows consistency with Chinese Academy of Sciences (CAS) DCB products. [ABSTRACT FROM AUTHOR]

The structure and mechanical properties of C/C composites prepared by isothermal isobaric chemical vapor infiltration (ICVI) were investigated to evaluate the influence of introducing graphene. The results indicated that adding graphene significantly improved the texture of pyrocarbon. The pure pyrocarbon was primarily composed of smooth laminar (SL) structure, while the pyrocarbon in composites containing graphene was dominated by regenerative laminar (ReL) structure. Furthermore, with 0.66 wt% addition of graphene, the compression performance of the C/C composites was prominently improved by 70.9%, increasing from 107.37 MPa to 183.45 MPa, while the bending strength of the C/C composites was slightly decreased. The variation of mechanical properties was attributed to graphene-induced weakening of interfacial bonding and improved texture of pyrocarbon, resulting in a more compact arrangement of carbon layers and better integrity of the matrix. This work contributed to the understanding of the improved properties and structure of C/C composites with graphene addition. [ABSTRACT FROM AUTHOR]

Background: Clinical and animal studies demonstrated that neuroinflammation from anesthesia (sevoflurane) is the main contributor to cause perioperative neurocognitive disorders (PND). Recently, it was reported that microglia respond to hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, which was the target of sevoflurane. Whether HCN channels are involved in the induction of neuroinflammation after sevoflurane exposure is still unclear. Results: Sevoflurane exposure had increased cognitive dysfunction and anxiety-like behaviors in rats. Rats inhaled with sevoflurane had activated microglia and increased neuroinflammation (IL-1β, IL-6, and TNF-α) in the hippocampus. RNA sequencing identified 132 DEGs (86 up-regulated and 46 down-regulated DEGs [differentially expressed genes]) in the hippocampus of PND rats. RNA-sequencing also uncovered that sevoflurane exposure down-regulates HCN2 expression. Pathway and process enrichment analysis suggests DEGs are mainly enriched in regulation of system process, positive regulation of glutamate secretion, secretion, regulation of synaptic transmission, regulation of nervous system process, behavior, negative regulation of sodium ion transport, and learning or memory. We validated that sevoflurane exposure can down-regulate the levels of PEX5R/Trip8b (an interaction partner and auxiliary subunit of HCN channels) and HCN1-4 channels in the hippocampus of PND rats. We used immunofluorescence staining to identify that HCN2 co-labels with neurons (Neun), astrocytes (GFAP), and microglia (iba1). We observed that the co-labeling of HCN2 with neurons or microglia decreased in the hippocampus and cortex after sevoflurane exposure. Blocking HCN2 by ZD7288 treatment further activated microglia and aggravated sevoflurane exposure-induced anxiety-like behavior, cognitive impairment, and neuroinflammation. Conclusions: We concluded that sevoflurane exposure can induce an increased level of neuroinflammation, microglial activation, cognitive dysfunction, and anxiety-like behaviors in rats. HCN2 channel, as the target of sevoflurane action, mediates this process. HCN2 might be a target for the treatment and prevention of sevoflurane-induced PND. [ABSTRACT FROM AUTHOR]

Background: Humane treatment requires the provision of appropriate sedation and analgesia during medical diagnosis and treatment. However, limited information is available about the status of procedural analgesic interventions in Chinese hospitals. Therefore, a nationwide survey was established to identify challenges and propose potential improvement strategies. Methods: Forty-three members of the Pain Group of Chinese Society of Anesthesiology established and reviewed the questionnaire, which included (1) general information on the hospitals, (2) the sedation/analgesia rate in gastrointestinal endoscopy, labor, flexible bronchoscopy, hysteroscopy in China, (3) staff assignments, (4) drug use for procedural analgesic interventions, and (5) difficulties in procedural analgesic interventions. The data were obtained using an online questionnaire sent to the chief anesthesiologists of Chinese hospitals above Grade II or members of the Pain Group of Chinese Society of Anesthesiology. Results: Valid and complete questionnaires were received from 2198 (44.0%) hospitals, of which 64.5% were Grade III. The overall sedation/analgesia rates were as follows: gastroscopy (50.6%), colonoscopy (53.7%), ERCP (65.9%), induced abortion (67.5%), labor (42.3%), hysteroscopy (67.0%) and fiber bronchoscopy (52.6%). Compared with Grade II hospitals, Grade III hospitals had a higher proportion of procedural analgesic interventions services except for induced abortion. On average (median [IQR]), each anesthesiologist performed 5.7 [2.3—11.4] cases per day, with 7.3 [3.2—13.6] performed in Grade III hospitals and 3.4 [1.8—6.8] performed in Grade II hospitals (z = -7.065, p < 0.001). Conclusions: Chinese anesthesiologists have made great efforts to achieve procedural analgesic interventions, as evidenced by the increased rate. The uneven health care provided by hospitals at different levels and in different regions and the lack of anesthesiologists are the main barriers to optimal procedural analgesic interventions. [ABSTRACT FROM AUTHOR]

Tensegrity structure is a prestressed self-equilibrated system consisting of compressed struts and tensioned tendons. The shape and position of tensegrity can be actively controlled by changing the lengths of members, making it attractive as a platform for adaptive bionic and locomotive robots. In this paper, the regular 30-strut tensegrity is used as the skeleton of a locomotive robot. The robot is flexible and highly redundant, making it adaptive to unconstrained environments and ideal for various co-robotic scenarios such as space exploration, emergency rescue, and so on. Compared with the 6-strut tensegrity robot, the 30-strut tensegrity robot with more controllable degrees of freedom possesses more various motion behaviors as well as gait primitives. To demonstrate the effectiveness of the motion behaviors of the 30-strut locomotive robot, we analyze the diverse collection of behaviors generated by actively changing the lengths of struts. It is found that rolling motion is robust and easy to be actuated, and multi-gait and individual-gait of rolling motion are observed. However, its high dimensionality and strong dynamic nature complicate the motion control. A physical prototype is manufactured to verify the found motion behaviors. The results show the potential uses of 30-strut tensegrity as multifunctional locomotive robots. [ABSTRACT FROM AUTHOR]

Sparse code multiple access (SCMA) is a promising non-orthogonal multiple access technique to support massive connectivity for future wireless Internet of Things (IoT) networks. As the main feature of SCMA, modulation and spread spectrum is embedded into codebook mapping, offering significant codebook shaping gains to mitigate inter-cell interference. Maximizing the constellation-constrained average mutual information (AMI) is an effective way for SCMA codebook optimization. However, deriving a closed-form expression of the AMI is analytically intractable, while it is computationally costly to estimate the AMI by numerical methods. To address this challenge, this paper first derives a lower bound of the AMI with a closed-form expression. On this basis, we propose a novel codebook optimization method referred to as joint bare bones particle swarm optimization (JBBPSO) through maximizing the AMI lower bound. The proposed low-complexity method jointly optimizes the mother codebook including basic constellation and other non-zero-dimensional constellations, and the rotation angles of multiple users. Numerical results show that our proposed optimized codebooks outperform the state-of-the-art SCMA codebooks in terms of both the lower bound and the error performance. [ABSTRACT FROM AUTHOR]

This article presents a control strategy to improve the energy efficiency of a quadrotor for field inspections. A power consumption analytical model for a quadrotor is constructed, which indicates that the power consumption of a quadrotor is correlated with the roll and pitch angles. Based on that, a cascaded bounded control framework is developed to regulate the roll and pitch angles within the predefined energy-efficient ranges, while a successful inspection trajectory tracking can be achieved simultaneously. Experimental studies are carried out to prove the effectiveness of the proposed method through a mock-up scenario of wind farm inspection. Compared to the conventional cascaded control framework, the proposed energy saving control strategy is capable of saving 5% energy for the same inspection assignment under wind disturbance. [ABSTRACT FROM AUTHOR]

Adaptive structures can counteract the effect of external loads and other environmental actions through active manipulation of the internal force flow (i.e., the load path) and geometry (i.e., form or shape). Previous studies have shown that adaptation enables significant mass and energy saving compared to conventional structures that resist the effect of loading solely through material strength and stiffness (i.e., passive structures). The computational synthesis of adaptive structures is a challenging process since it involves optimization of the structural layout as well as sensor and actuator placement, which is, generally, a Mixed-Integer Non-linear Programming (MINLP) problem. Previous formulations employ sizing and/or geometry optimization in combination with actuator placement optimization. No method has yet been formulated for the simultaneous synthesis of the structural topology, element sizing, and placement of actuators. This paper offers the first-ever formulation for the All-In-One (AIO) topology optimization of adaptive structures based on the Ground Structure approach. The objective function comprises the mass of structural elements and actuators. The design variables are structural topology, element cross-section areas, and actuator locations. State variables include element forces and deformations, nodal displacements, and actuator commands. Constraints ensure that feasible solutions satisfy equilibrium and geometric compatibility as well as limits on stress, stability, nodal displacements, and actuator forces. Auxiliary constraints are implemented to enable the simultaneous synthesis of the structural layout and actuator placement and linearize the formulation into a Mixed-Integer Linear Problem (MILP) that can be solved to a global optimum. Due to a large number of variables, the AIO formulation can be typically applied to small-scale problems. To reduce the computational cost, a two-step sequential formulation is developed and benchmarked against the AIO method. Results show that the sequential method produces solutions of similar quality compared to the AIO one albeit with a significantly reduced computational cost. Results confirm that the optimal adaptive solutions vastly outperform topology-optimized conventional (i.e., passive) solutions. Adaptive solutions approach the limit of material economy (fully stressed design, e.g., Michell trusses) and, in parallel, satisfy important constraints including displacements and stability that would not be possible without adaptation. [ABSTRACT FROM AUTHOR]

Rocuronium is widely utilized in clinical general anaesthesia, and individual differences in pharmacology and clearance have been observed. Two hundred thirty‐six Chinese patients undergoing selective thyroid/breast mass resection were studied. Total intravenous anaesthesia was induced with a single dose of propofol (2 mg·kg−1), sufentanil (0.5 μg·kg−1), and rocuronium (0.6 mg·kg−1) and maintained with propofol (3–5 mg·kg−1·h−1) and remifentanil (0.2–0.4 μg·kg−1·min−1). Intubation conditions and a train‐of‐four index of patients were utilized to assess the effects and duration of rocuronium. The data from 228 patients were analysed and reported. Genotypes NR1I2 rs2472677 C > T, NR1I2 rs6785049 G > A, SLCO1B1 rs4363657 T > C, SLCO1A2 rs4762699 T > C, and UGT1A1 rs4148323 G > A contributed to individual variation in rocuronium. Of the clinical variables tested, age, BMI, total dose of propofol, NR1I2 rs2472677, and SLCO1A2 rs4762699 correlated significantly (P < 0.05 for all) with the clinical duration or total clinical action time of rocuronium in a multiple linear regression model. No significant interactions were observed in intubation conditions. Genetic variations in NR1I2 rs2472677, NR1I2 rs6785049, SLCO1B1 rs4363657, SLCO1A2 rs4762699, and UGT1A1 rs4148323 were related to extensive interindividual variability in the clinical duration and total clinical action time of rocuronium. [ABSTRACT FROM AUTHOR]

Willows (Salix) are some of the most abundant shrubs in cold alpine and tundra biomes. In alpine regions, seed dispersal is not limiting upwards willow expansion, so the upslope shift of willow shrublines is assumed to be a response to climatic warming. Very little, however, is known about the recent spatiotemporal dynamics of alpine willow shrublines. The world's highest willow shrublines (ca 4900 m a.s.l.) are located on the Tibetan Plateau (TP) and provide a rare opportunity to test their sensitivity and responses to rapid warming and the associated increase in the demand for water in ecosystems. We used a new data set comprising 24 Salix shrubline plots along a 900‐km latitudinal gradient (30‒38°N) to reconstruct the rates of annual shrub recruitment and shifting shrubline positions since 1939. Shrub densification and shrubline advances were promoted by pronounced summer warming before 2010, contributing to widespread greening on the TP. These trends, however, reversed due to warming‐induced moisture limitation after 2010, which thus represented a tipping point of warming/drying trade‐offs. Climatic warming and drying are predicted to accelerate in the following decades, so alpine plant communities may be at an increasing risk of population decline or even range contraction. [ABSTRACT FROM AUTHOR]

Elucidating the mechanisms of electrochemiluminescence (ECL) generation is crucial for developing novel ECL systems, designing new luminophores and coreactants, and expanding the application of ECL in different fields. Diverse methods have been developed so far for this purpose, among which spatially resolved measurements using ECL microscopy (ECLM), scanning electrochemical microscopy (SECM) and ECL self‐interference spectroscopy (ECLIS), are particularly valuable in terms of their ability to measure the distribution of excited luminophores and coreactant radicals. This review aims to provide an overview of research progress on deciphering the mechanisms of ECL by spatially resolved measurements. The reaction pathways for ECL generation are briefly introduced and then the advances in understanding the mechanisms of ECL reaction in solutions and on the surface of microbeads are summarized. A personal perspective covering both mechanisms and challenges is finally presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • More mineral species crystallize from the GE coal gasification molten slags. • Mineral compositions imply the similarity between coal gasification and magmatism. • Mineralogy of the GE gasification residues indicate the possibility of slagging. Minerals are the dominant impurities in coal and their changes in gasifiers could cause many problems such as fouling, slagging, and ash deposition. The mineralogy of the coal gasification residues derived from two commercial entrained-flow coal gasification plants from the Ningdong Energy and Chemical Industry Base were determined. A range of minerals were detected by the analyses of X-ray diffraction and scanning electron microscope with associated energy-dispersive X-ray spectrometer (SEM–EDS). The mineral species formed in General Electric (GE) gasification were more abundant than that in the Gaskombinat Schwarze Pumpe (GSP) gasification. The neoformed minerals such as grossular and hedenbergite detected in the residues indicated that the gasification processes share some similarities with magmatism in geological system. The existence of wustite in the GE coal gasification residues indicated the reductive environment in the GE gasifier. Compared to the GSP feed coals, the higher proportions of calcite, pyrite, and siderite and the higher Na contents in the GE feed coals indicated that the ash problems probably happen in the coal-water slurry gasification. Reducing the proportions of those Na-, Ca-, and Fe-containing mineral from the feed coal is necessary for the improvement of the coal gasification process. [ABSTRACT FROM AUTHOR]

Summary: LiFePO4 carbon coating technology has been widely used in the lithium ion industries. However, there are still many challenges such as low ionic conductivity. This paper compares the residual carbon rate and electrical conductivity of sucrose, glucose, and soluble starch, and proposes a secondary carbon coating technology. The carbon‐coated lithium iron phosphate cathode material (LiFePO4/C) overcoated with soluble starch to improve the initial carbon layer. A variety of test methods are used to analyze the LiFePO4/C cathode. The results show that under the soluble starch coating of 20 wt%, particle size and morphology do not change significantly, surface graphitization degree and electrical conductivity increase, and thus electrochemical performance is improved. At the charge and discharge rate of 0.1 C, the specific discharge capacity of the first cycle is 27.7% higher than that of the initial sample, and the cycle stability is also significantly improved. The mechanism of soluble starch coating carbon layer on LiFePO4 cathode is studied. [ABSTRACT FROM AUTHOR]

This paper gives a new formulation to design adaptive structures through total energy optimization (TEO). This methodology enables the design of truss as well as tensegrity configurations that are equipped with linear actuators to counteract the effect of loading through active control. The design criterion is whole-life energy minimization which comprises an embodied part in the material and an operational part for structural adaptation during service. The embodied energy is minimized through simultaneous optimization of element sizing and actuator placement, which is formulated as a mixed-integer nonlinear programming problem. Optimization variables include element cross-sectional areas, actuator positions, element forces, and node displacements. For tensegrity configurations, the actuators are not only employed to counteract the effect of loading but also to apply appropriate prestress which is included in the optimization variables. Actuator commands during service are obtained through minimization of the operational energy that is required to control the state of the structure within required limits, which is formulated as a nonlinear programming problem. Embodied and operational energy minimization problems are nested within a univariate optimization process that minimizes the structure's whole-life energy (embodied + operational). TEO has been applied to design a roof and a high-rise adaptive tensegrity structure. The adaptive tensegrity solutions are benchmarked with equivalent passive tensegrity as well as adaptive truss solutions, which are also designed through TEO. Results have shown that since cables can be kept in tension through active control, adaptive tensegrity structures require low prestress, which in turn reduces mass, embodied energy, and construction costs compared to passive tensegrity structures. However, while adaptive truss solutions achieve significant mass and energy savings compared to passive solutions, adaptive tensegrity solutions are not efficient configurations in whole-life energy cost terms. Since cable elements must be kept in tension, significant operational energy is required to maintain stable equilibrium for adaptation to loading. Generally, adaptive tensegrity solutions are not as efficient as their equivalent adaptive truss configurations in mass and energy cost terms. [ABSTRACT FROM AUTHOR]

• We identify the cost-effectiveness of protected area (PA). • PA increases biodiversity and promote ecosystem service. • Three targets are set for each prefecture with specific cost-effective zones. • Four categories of prefectures require special attention for policymakers. • We provide implications on prefectural priorities and remedy weakness of PA. Biodiversity and ecosystem services are seriously threatened by human activities, and there have been calls for the expansion of protected areas (PAs) to mitigate this situation. Currently, there is an urgent need to establish new PA cost-effectively from concentrating on biodiversity to including the provision of ecosystem services. Hence, a prefectural evaluation was conducted across the Qinghai-Tibet Plateau (QTP) to quantify endangered species habitat provision and three key ecosystem services to identify conservation priority zones (CPZs), which were then combined with low human footprint zones to determine cost–effective zones (CEZs). A scenario simulation, which contains conservative, moderate, and ambitious targets, was further proposed to conserve more CEZs for PA design. We found that biodiversity, ecosystem services, and human footprints varied significantly among the different taxonomic groups. CPZs and CEZs cover 33 and 28 % of the QTP, respectively, including almost all forest areas, and near medium and high elevations (approximately 3000 ∼ 4700 m). In comparison with existing PAs systems, the new PAs system is considering cost-effective in terms of biodiversity and ecosystem services, increasing 42–60 %, 32–46 %, and 62–69 %, and 47–62 % of the important habitats that serve mammals, birds, amphibians, and plants, respectively, and promoting 48–66 % carbon service, 37–54 % soil retention, and 22–37 % water yield. More importantly, it reduces conflict with the human footprint by up to 22 %. Moreover, the conservative, moderate, and ambitious targets conserved 44, 48, and 53 % of the QTP, respectively. These three targets were set for each prefecture and prefectural–level city with spatially specific CEZs recognized, providing some implications on prefectural PAs priorities for policymakers. [ABSTRACT FROM AUTHOR]

In present work, the superior high-temperature properties in a novel (Ni, Cr, Fe) 3 (Al, Ti, Cr)-γʹ (L1 2) type precipitation-strengthened Co-free medium-entropy alloy (MEA) was systematically evaluated. Experimental results indicate that this γʹ-strengthened alloy demonstrates excellent structure thermal stability and no other brittle intermetallic phases formed at grain boundaries or grain interior during long-term thermal exposures. The γʹ phase in this Co-free MEA exhibits an extraordinary sluggish coarsening rate, which is much lower than most conventional superalloys and recently developing γʹ-strengthened high/medium-entropy alloys (HEAs/MEAs). This γʹ-strengthened alloy also exhibits a good combination of high γʹ-solvus temperature (1068 °C) and low mass density (7.79 g/cm3). More significantly, this γʹ-strengthened MEA shows excellent high-temperature tensile strength, especially outstanding specific strength, which is superior to most Ni/Co-based superalloys. Our present work provides a useful illustration for designing advanced high-temperature alloys based on γʹ(L1 2)-strengthened HEAs/MEAs, rather than Ni-based/Co-based superalloys. [Display omitted] • A γʹ (L1 2)-strengthened Co-free MEA with superior high-temperature performance was developed. • The γʹ phase in this Co-free MEA exhibits an extraordinary sluggish coarsening rate. • The γʹ-strengthened MEA shows superior high-temperature tensile strength than Ni/Co-based superalloys. [ABSTRACT FROM AUTHOR]

This study proposes a general framework for topology-finding or topology optimization of tensegrity structures. The existing topology-finding formulation of tensegrity structures based on mixed-integer linear programming (MILP) was improved and transformed into a formulation based on mixed-integer semidefinite programming (MISDP) which considers the global stability condition of tensegrity. We illustrated and analyzed two undesirable phenomena, loss of prestress stability and loss of integrity, caused by the missing global stability condition in previous MILP-based approaches. A branch-and-bound algorithm combined with a primal-dual interior-point algorithm is employed to solve the proposed MISDP model. Some numerical examples illustrated the improvements and effectiveness of the proposed approach. The proposed approach successfully can avoid the two undesirable phenomena and ensure the global stability of the found tensegrity structures. By using different stability conditions in the topology-finding process, the proposed approach can find general stable tensegrity structures and superstable tensegrity structures. [ABSTRACT FROM AUTHOR]

Environmental hypobaric hypoxia induces several physiological or pathological responses in individuals in high-altitude regions. Salvia przewalskii Maxim (Labiatae) (SPM) is a traditional Chinese herbal medicine and has known antibacterial, antiviral, antioxidant, anti-thrombotic, and anti-depressant activities. This study examined the antihypoxia effects of SPM in vivo. The dried and pulverised of SPM was extracted from root crude drug with 70% ethanol with ultrasound. Male Sprague-Dawley rats were divided into three groups (n = 10): normal group, hypoxia group (altitude of 4260 m), and hypoxia + SPM group (altitude of 4260 m, SPM of 1.0 g/kg/day). The experiment persisted for 4 weeks. The mean pulmonary arterial pressure (mPAP), hypoxia-inducible factor-1α (HIF-1α) mRNA, and lung pathology were analysed using pulmonary artery pressure recorder, quantitative polymerase chain reaction, and histopathological analysis. Moreover, the effects of SPM on lung proteomes during hypoxia were observed by a TMT-based proteomic approach. Pre-treatment with SPM decreased mPAP (24.86%) and HIF-1α (31.24%), and attenuated the pathological changes in lung tissues. In addition, a total of 28 proteins were differentially expressed in lung of hypoxia + SPM group (fold change > ± 1.2 and p < 0.05). The differentially altered proteins were primarily associated with antioxidative stress, as evidenced by the downregulated expression of Adh7, Cyp2d1, Plod2, Selenow, ND3, and Fabp1, and fructose metabolism, as evidenced by the downregulated expression of Khk and Aldob. These results suggested that SPM is a promising drug for antihypoxia. The mechanism of action might be related to increasing antioxidant capacity and inhibiting fructose metabolism. [ABSTRACT FROM AUTHOR]

Phthalonitrile resin/exfoliated hexagonal boron nitride (h -BN) composites with high thermal conductivity were fabricated using a novel approach. The route included two steps, micro- h -BN was coated and dispersed by phthalonitrile monomers via the function of heterogeneous nucleation, and then micro- h -BN was exfoliated by heat release during the phthalonitrile curing process. The composites achieved a high thermal conductivity of 0.736W (m·K)−1 containing 20 wt% micro- h -BN, which is 3.17 times higher than that of pure phthalonitrile resin at 0.232W (m·K)−1. Compared to traditional routes, the novel preparation approach requires less BN fillers when improving the same thermal conductivity. Importantly, other thermosetting polymers can also encapsulate BN through this strategy, which paves a new way for preparing thermally conductive thermosetting polymer–matrix composites. [ABSTRACT FROM AUTHOR]

Herein, we report an approach with sub-micrometer spatial resolution for studying local electrochemistry based on thin-film optical interference. The spatial resolution is achieved by successive interferometric imaging of a nanochannel membrane coated electrode during an electrochemical (EC) reaction. The EC reaction of redox molecules on the electrode induces variation of the refractive index of the nanochannel membrane, leading to changes of the intensity of interferometric light. Local EC reactions thus can be studied from the optical signal. The refractometry-based approach is versatile and label-free, and has promising application in nanosensing and nanocatalysis. [ABSTRACT FROM AUTHOR]

This study presents a general approach to the topology design of tensegrities with rigid bodies. To the best of the authors' knowledge, all existing topology design methods of tensegrities focus on tensegrities that only consist of members carrying axial forces, which are referred to herein as classic tensegrities. However, another category of tensegrities, referred to as general tensegrities, contains rigid bodies aside from axially loaded members. The equilibrium and stability conditions of general tensegrities are different from those of classic tensegrities because of the existence of rigid bodies, which makes the existing topology design methods invalid for general tensegrities. In this study, the equilibrium and stability conditions of general tensegrities are first derived. A topology design approach for general tensegrities is then proposed based on a mixed-integer linear programming optimization scheme. The topology (i.e., member connectivities) is treated as a binary variable, and the member forces are treated as continuous variables. Three essential attributes, namely self-equilibrium, unilateral member force, and class- k condition, of a general tensegrity, as well as some other practical requirements, are formulated as constraints. Different objective functions are employed to design different general tensegrities. Some well-known general tensegrities are reproduced, and various numerical examples are presented to verify the effectiveness and versatility of the proposed approach. The proposed topology design method is verified to be a truly general approach for the topology design of tensegrities with or without rigid bodies. [ABSTRACT FROM AUTHOR]

This paper presents a new force method to predict the structural response of statically and kinematically indeterminate systems that can be stabilized through prestress, i.e. prestress-stable structures. This new force method, here named Extended Integrated Force Method (IFME), extends the existing Integrated Force Method (IFM) which is only applicable to the analysis of kinematically determinate systems. The product force concept is adopted and incorporated into the IFME to model the effect of infinitesimal mechanisms. This makes the IFME capable of dealing with cases in which the external loads contain components that cannot be taken by the system in its initial configuration. As the original IFM, the IFME bypasses the well-known concept of redundant forces and basis determinant structure of the Standard Force Method (SFM) by taking the internal forces as the independent variables which are obtained simultaneously. A proof is provided to show that, when the product force is not included in the formulation, the IFME reduces to the IFM for kinematically determinate systems and it also reduces to another force method based on singular value decomposition of the equilibrium matrix which is here named SVD-FM. Compared to the better known Displacement Method (DM), the IFME is a suitable alternative and it offers a deeper insight into the structure response which is decoupled into an extensional and an inextensional part for prestress-stable kinematically indeterminate systems. Numerical examples are carried out to test accuracy and effectiveness of the IFME on kinematically indeterminate structures with multiple self-stress states and mechanism modes. Application of the IFME to active structural control of kinematically indeterminate systems is also discussed through a numerical example. [ABSTRACT FROM AUTHOR]

Previous studies suggested that alterations in the energy metabolism might be underlying cancer initiation and progression. Polymorphisms of genes involved in energy metabolism regulation, such as peroxisome proliferator-activated receptor gamma coactivator 1α (PPARGC1A), -β (PPARGC1B), and paraoxonase 1 (PON1), might confer susceptibility to esophageal squamous cell carcinoma (ESCC) and partially explain its pathogenesis. We investigated the effects of several single nucleotide polymorphisms (SNPs) in three metabolic-related genes (e.g., PPARGC1A, PPARGC1B, and PON1) on ESCC susceptibility. In total, 829 patients with sporadic ESCC and 1522 nontumor controls were enrolled in the study. SNPs were genotyped using PCR-ligase detection reaction. Our study revealed that the PPARGC1A rs3736265 G/A SNP significantly increased the risk for ESCC (GA vs. GG: adjusted odds ratio [OR] = 1.25, 95% confidence interval [95% CI] = 1.02–1.54, p = 0.034; GA+AA vs. GG: adjusted OR = 1.25, 95% CI = 1.03–1.52, p = 0.027]. In addition, a stratified analysis revealed that the PPARGC1A rs3736265 SNP was correlated with the development of ESCC in male and nondrinking subgroups. We also confirmed that the PPARGC1B rs17572019 G/A SNP promoted the risk of ESCC in subgroup with high alcohol intake. The PPARGC1A rs8192678 C/T polymorphism decreased the susceptibility of ESCC in men. These findings highlight that polymorphisms in PPARGC1A and PPARGC1B may contribute to ESCC susceptibility. In the future, further well-designed epidemiological studies are needed to confirm our findings. [ABSTRACT FROM AUTHOR]

Diabetic hearts are more susceptible to myocardial ischemia/reperfusion (I/R) injury and less sensitive to ischemic postconditioning (IPostC), but the underlying mechanisms remain unclear. PKCβ2 is preferentially overactivated in diabetic myocardium, in which autophagy status is abnormal. This study determined whether hyperglycemia-induced PKCβ2 activation resulted in autophagy abnormality and compromised IPostC cardioprotection in diabetes. We found that diabetic rats showed higher cardiac PKCβ2 activation and lower autophagy than control at baseline. However, myocardial I/R further increased PKCβ2 activation and promoted autophagy status in diabetic rats. IPostC significantly attenuated postischemic infarct size and CK-MB, accompanied with decreased PKCβ2 activation and autophagy in control but not in diabetic rats. Pretreatment with CGP53353, a selective inhibitor of PKCβ2, attenuated myocardial I/R-induced infarction and autophagy and restored IPostC-mediated cardioprotection in diabetes. Similarly, CGP53353 could restore hypoxic postconditioning (HPostC) protection against hypoxia reoxygenation- (HR-) induced injury evidenced by decreased LDH release and JC-1 monomeric cells and increased cell viability. These beneficial effects of CGP53353 were reversed by autophagy inducer rapamycin, but could be mimicked by autophagy inhibitor 3-MA. It is concluded that selective inhibition of PKCβ2 could attenuate myocardial I/R injury and restore IPostC-mediated cardioprotection possibly through modulating autophagy in diabetes. [ABSTRACT FROM AUTHOR]

Aims: Non-native trees are widely used to prevent soil erosion in the Loess Plateau. We aim to investigate the effects of non-native tree plantations on the communities of understory plants and soil macroinvertebrates. Methods: The soil, understory plants and soil macroinvertebrates were sampled in non-native Robinia pseudoacacia (RP) and Populus ×canadensis (PC) stands, and native Armeniaca sibirica (AS) stands. Results: Abundance and richness of understory plants were significantly greatest in the RP stands. The macroinvertebrates collected belonged to 13 orders across all stands. At the community level, richness did not differ among the stand types, but the abundance was significantly greatest in the PC stands. At the functional group level, phytophages and detritivores preferred the PC stands, whereas predators preferred the RP stands. The generalist macroinvertebrate abundance was significantly greatest in the PC stands. Moreover, the community composition of understory plants clearly differed among the stand types; that of soil macroinvertebrates in the PC stands was separated from the other stand types, which was mediated by environmental variables, especially the soil temperature and soil organic carbon. Conclusions: Non-native tree plantations had positive effects on the overall abundance of understory plants and soil macroinvertebrates, but their effects on functional groups were inconsistent, associated with tree identity. The selection of non-native tree should be considered in term of multiple trophic levels, if afforestation has biodiversity objectives. [ABSTRACT FROM AUTHOR]

Electrochemistry has been developed toward high spatial resolution and throughput during the past decades to match the growing demands for studying heterogeneous electrodes and nanomaterials that are widely used in electrocatalysis, electroanalysis and energy conversion. Combining optical methods with electrochemistry enables us to obtain local electrochemical information via a noninvasive way. Optical methods also possess high throughput, which are beneficial to investigate large amounts of nanoelectrodes or nanocatalysts simultaneously, and to develop electrochemical multiplex sensors. This article critically reviews the optical methods that have been developed with spatial resolution for imaging electrochemical reactions and processes in the nanometer-scale. Recent development on these methods, such as plasmonics-based electrochemical current microscopy (PECM), dark field microscopy (DFM), Raman spectroscopy, fluorescence microscopy (FLM) and electrogenerated chemiluminescence (ECL), and research progress in the relevant fields, particularly nanocatalysis and single particle/molecule electrochemistry, will be briefly overviewed. Finally, current limitations and trends of these optical methods and potential strategies to further improve the spatial resolution of electrochemistry are discussed. Image 1 • Optical techniques employed to study local electrochemistry are critically reviewed. • The emphasis is placed on the principles of techniques and recent research progress. • Nanocatalysis and single molecule/particle electrochemistry are briefly overviewed. [ABSTRACT FROM AUTHOR]

The elimination of cyanobacteria is frequently required for treating and controlling the waters with harmful algal blooms. In this study, an improved flotation technology was developed using colloidal gas aphrons (CGAs) surface-modified with the inorganic coagulant of polyaluminum chloride (PACl); the Microcystis aeruginosa (M. aeruginosa) cells were efficiently removed and their re-growth was effectively inhibited. The so-created coagulative CGAs (CCGAs) exhibited the attractive characteristics of both CGAs and PACl for the cell removal. The experimental results clearly showed that 94.2–99.2% of cells were removed within 3 min at the optimum dosage of cetyltrimethyl ammonium bromide (CTAB) and PACl at three different initial cell densities (OD 680 = 0.05, 0.26 and 0.76); and the re-growth of M. aeruginosa did not occur in 10 days. The flocs derived from the CCGA-flotation were of smaller size and looser configuration in contrast with those obtained from coagulation-flotation. The CCGAs were robust in charge neutralization, cell capture, cell attack and destruction. Even at low CTAB dosages, those bubbles could provide large surface area for capturing the M. aeruginosa cells in both unicellular and colonial form compared with the unmodified CTAB-CGAs. The CCGAs reduced 59.5–87.9% of CTAB dosage with the assistance of PACl and the required flotation retention time was largely shortened in comparison with the sedimentation and flotation-based treatment options. This would lead to low treatment cost and sludge production. The present work provides a novel insight into the development of flotation technologies for treating and controlling dense harmful algal blooms. Image 1 • Polyaluminum chloride-modified microbubbles fast eliminate Microcystis aeruginosa. • Long-term re-growth inhibition is reached using coagulative colloidal gas aphrons. • Coagulative colloidal aphrons largely reduce the surfactant and coagulant dosage. • Coagulative aphrons are good at charge neutralization, cell capture & destruction. [ABSTRACT FROM AUTHOR]

In exploring oscillator synchronization, a general observation is that as the oscillators become nonidentical, e.g., introducing parameter mismatch among the oscillators, the propensity for synchronization will be deteriorated. Yet in realistic systems, parameter mismatch is unavoidable and even worse in some circumstances, the oscillators might follow different types of dynamics. Considering the significance of synchronization to the functioning of many realistic systems, it is natural to ask the following question: Can synchronization be achieved in networked oscillators of clearly different parameters or dynamics? Here, by the model of networked chaotic oscillators, we are able to demonstrate and argue that, despite the presence of parameter mismatch (or different dynamics), stable synchronization can still be achieved on symmetric complex networks. Specifically, we find that when the oscillators are configured on the network in such a way that the symmetric nodes have similar parameters (or follow the same type of dynamics), cluster synchronization can be generated. The stabilities of the cluster synchronization states are analyzed by the method of symmetry-based stability analysis, with the theoretical predictions in good agreement with the numerical results. Our study sheds light on the interplay between symmetry and cluster synchronization in complex networks and give insights into the functionalities of realistic systems where nonidentical nonlinear oscillators are presented and cluster synchronization is crucial. [ABSTRACT FROM AUTHOR]

Aims: To investigate the role of FOXO1 in STAT3 activation and mitochondrial quality control in the diabetic heart. Methods: Type 1 diabetes mellitus (T1DM) was induced in rats by a single intraperitoneal injection of 60 mg · kg−1 streptozotocin (STZ), while type 2 diabetes mellitus (T2DM) was induced in rats with a high‐fat diet through intraperitoneal injection of 35 mg · kg−1 STZ. Primary neonatal mouse cardiomyocytes and H9c2 cells were exposed to low glucose (5.5 mM) or high glucose (HG; 30 mM) with or without treatment with the FOXO1 inhibitor AS1842856 (1 μM) for 24 hours. In addition, the diabetic db/db mice (aged 8 weeks) and sex‐ and age‐matched non‐diabetic db/+ mice were treated with vehicle or AS1842856 by oral gavage for 15 days at a dose of 5 mg · kg−1 · d−1. Results: Rats with T1DM or T2DM had excessive cardiac FOXO1 activation, accompanied by decreased STAT3 activation. Immunofluorescence and immunoprecipitation analysis showed colocalization and association of FOXO1 and STAT3 under basal conditions in isolated cardiomyocytes. Selective inhibition of FOXO1 activation by AS1842856 or FOXO1 siRNA transfection improved STAT3 activation, mitophagy and mitochondrial fusion, and decreased mitochondrial fission in isolated cardiomyocytes exposed to HG. Transfection with STAT3 siRNA further reduced mitophagy, mitochondrial fusion and increased mitochondrial fission in HG‐treated cardiomyocytes. AS1842856 alleviated cardiac dysfunction, pathological damage and improved STAT3 activation, mitophagy and mitochondrial dynamics in diabetic db/db mice. Additionally, AS1842856 improved mitochondrial function indicated by increased mitochondrial membrane potential and adenosine triphosphate production and decreased mitochondrial reactive oxygen species production in isolated cardiomyocytes exposed to HG. Conclusions: Excessive FOXO1 activation during diabetes reduces STAT3 activation, with subsequent impairment of mitochondrial quality, ultimately promoting the development of diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

The quality of farmland soils on the Tibetan Plateau is important because of the region's ecological vulnerability and their close link with local food security. Investigation on the pollution status of heavy metal (loid)s (HMs) in the farmlands of Lhasa and Nyingchi on the Tibetan Plateau, China revealed that Cu, As, Cd, Tl, and Pb were apparently enriched, with the soil parent materials being the primary sources of the soil HMs. Overall, the farmlands in Lhasa had higher contents of HMs compared to those in Nyingchi, which could be attributed to the fact that the former were mainly developed on river terraces while the latter were mainly developed on the alluvial fans in mountainous areas. As displayed the most apparent enrichment, with the average contents in the vegetable field soils and grain field soils of Lhasa being 2.5 and 2.2 times higher compared to those of Nyingchi. The soils of vegetable fields were more heavily polluted than those of grain fields, probably due to the more intensive input of agrochemicals, particularly the use of commercial organic fertilizers. The overall ecological risk of the HMs in the Tibetan farmlands was low, while Cd posed medium ecological risk. Results of health risk assessment show that ingestion of the vegetable field soils could pose elevated health risk, with children facing greater risk than adults. Among all the HMs targeted, Cd had relatively high bioavailability of up to 36.2% and 24.9% in the vegetable field soils of Lhasa and Nyingchi, respectively. Cd also showed the most significant ecological and human health risk. Thus, attention should be paid to minimize further anthropogenic input of Cd to the farmland soils on the Tibetan Plateau. [Display omitted] • Vegetable fields were more polluted by HMs than grain fields on the Tibetan Plateau. • Cd was the top polluting HM species and had the highest bioavailability of >36%. • Parent materials were the dominant sources for HMs in the Tibetan farmland soils. • HMs in the farmland soils could pose health risk to local children, but not to adults. • HM inputs with intensive agrochemical use in vegetable production deserve attention. [ABSTRACT FROM AUTHOR]

Impacts of climatic means on spring phenology are well documented, whereas the role of climatic variance, such as occurrence of spring frosts, has long been neglected. A large elevational gradient of forests on the southeastern Tibetan Plateau provides an ideal platform to explore correlates of spring phenology and environmental factors. We tested the hypothesis that spring frost was a major factor regulating the timing of bud-leaf phenology by combining 5 years of in situ phenological observations of Abies georgei var. smithii with concurrent air temperature data along two altitudinal gradients. Mean lapse rate for the onset of bud swelling and leaf unfolding was 3.1 ± 0.5 days/100 m and 3.0 ± 0.6 days/100 m, respectively. Random forest analysis and conditional inference trees revealed that the frequency of freezing events was a critical factor in determining the timing of bud swelling, independent of topographic differences, varying accumulation of chilling days, and degree-days. In contrast, the onset of leaf unfolding was primarily controlled by the bud swelling onset. Thus, the timing of bud swelling and leaf unfolding appear to be controlled directly and indirectly, respectively, by spring frost. Using space-for-time substitution, the frequency of spring freezing events decreased by 7.1 days with 1 °C of warming. This study provides evidence for impacts of late spring frosts on spring phenology, which have been underappreciated in research on phenological sensitivity to climate but should be included in phenology models. Fewer spring freezing events with warming have important implications for the upward migration of alpine forests and treelines. [ABSTRACT FROM AUTHOR]

Abstract With the rapid and wide application of the coal gasification technology in China, the corresponding environmental issues require increasing attention. In this study, the feed coal, coal gasification wastewater samples at key technical links, and the coal gasification residues were collected from three entrained-flow coal gasification plants in Northwest China and were characterized to understand the migration and partition of 21 potentially hazardous trace elements (PHTEs) in coal gasification process and their potential environmental impacts. Compared with Chinese coal, the concentrations of the PHTEs in the feed coals are mainly at the level of "depleted" and "normal". Undergoing the heating process in the gasifier, purification procedure for the syngas, and the residue-wastewater separation, the PHTEs in the feed coals are transferred into gaseous phase, wastewater, and gasification residues. The PHTEs are easier to be released into the gaseous phase during the GSP gasification process compared with the OMB and GE gasification processes. The chalcophile elements Zn, As, Se, Cd, Sb, Tl, Pb, and Hg tend to be enriched in the fine residues, and the retention capability of Hg by the residues is the lowest. With the grey water circulation and the use of additives, the black water samples have higher PHTEs concentrations than other water samples. Except for Sr, Mo, Sb, and Cs, most of the elements in the original water samples can be reduced effectively by removing the particulate matters. In some cases, Cr6+, Zn, As, Se, Cd, and Pb in the original wastewater samples exceed the limit for industrial use as indicated in the Chinese Environmental Quality Standards for Surface Water and the Emission Standard for Pollutants from Coal Industry. The potential environmental impacts of As and Se in the water cannot be reduced by filtration. The environmental impacts of the coal gasification residues should be further evaluated. Graphical abstract Unlabelled Image Highlights • The wastewater from the key technical links of gasification was characterized. • Potentially hazardous trace elements behaved differently in three gasification processes. • Soluble Sr, Mo, Sb, and Cs cannot be reduced effectively by removing particles. [ABSTRACT FROM AUTHOR]

Among forest ecosystems, the alpine treeline ecotone can be considered to be a simplified model to study global ecology and climate change. Alpine treelines are expected to shift upwards in response to global warming given that tree recruitment and growth are assumed to be mainly limited by low temperatures. However, little is known whether precipitation and temperature interact to drive long‐term Himalayan treeline dynamics. Tree growth is affected by spring rainfall in the central Himalayan treelines, being good locations for testing if, in addition to temperature, precipitation mediates treeline dynamics. To test this hypothesis, we reconstructed spatiotemporal variations in treeline dynamics in 20 plots located at six alpine treeline sites, dominated by two tree species (birch, fir), and situated along an east–west precipitation gradient in the central Himalayas. Our reconstructions evidenced that treelines shifted upward in response to recent climate warming, but their shift rates were primarily mediated by spring precipitation. The rate of upward shift was higher in the wettest eastern Himalayas, suggesting that its ascent rate was facilitated by spring precipitation. The drying tendency in association with the recent warming trends observed in the central Himalayas, however, will likely hinder an upslope advancement of alpine treelines and promote downward treeline shifts if moisture availability crosses a critical minimum threshold. Our study highlights the complexity of plant responses to climate and the need to consider multiple climate factors when analyzing treeline dynamics. Based on 20 treeline plots along an east–west precipitation gradient in the central Himalayas, this research showed that treelines shifted upward in response to recent climate warming, but their shift rates were mediated by spring precipitation. The drying tendency in association with the recent warming trends observed in the central Himalayas, however, will likely hinder an upslope advancement of alpine treelines and promote downward treeline shifts if moisture availability crosses a critical minimum threshold. Our study highlights the complexity of plant responses to climate and the need to consider multiple climate factors when analyzing treeline dynamics. [ABSTRACT FROM AUTHOR]

A coal containing high concentrations of hazardous trace elements F, V, Cr, Se, Mo, Cd, and U was selected for the gasification experiment based on the Lurgi fixed-bed pressurized gasifier. The feed coal was a super-high organic sulfur coal sampled from the Ganhe Mine, Yanshan Coalfield, Yunnan Province, China. Fluorine, Ga, Se, Cd, In, Tl, Pb, and Bi were volatilized during gasification, whereas V, Mo, and U were significantly enriched in the residue. The erosion of the gasifier internals resulted in the abnormal enrichment of Cr and Ni in the residue, with the maximum concentrations of Cr and Ni of 26,073 μg/g and 23,982 μg/g, respectively. Except for quartz, other minerals in the feed coals were transformed. The newly formed phases such as mullite, hercynite, magnetite, Fe aluminosilicate, and Al-Si-O-glass containing Fe-Ca-Mg-V-K-Ti were identified in the gasification residue. Pyrite was transformed to elemental iron in some cases. Pyrrhotite with a magnetite rim, representing the high temperature transformation product of pyrite, was observed in the gasification residue by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

A comprehensive understanding of precipitation behaviors, including phase transformation, morphology and distribution of precipitates, and their impacts on mechanical properties and deformation mechanisms is very important for the development of precipitation-hardened high/medium-entropy alloys (HEAs/MEAs). In this work, a Ti-alloyed MEA was successfully fabricated and systematically investigated. Experimental results reveal that two types of precipitates, i.e. intragranular spherical L1 2 and intergranular lamellar long-period stacking ordered (LPSO) precipitates with same stoichiometry, are coexist at early aging state in this Ti-alloyed MEA, which result in superior mechanical properties. With aging process continuous, the L1 2 phase could abnormally transforms to the LPSO phase, and this abnormal transformation originates from geometrical modification of the compact planes stacking sequences. Furthermore, the effects of abnormal phase transformation on mechanical properties and deformation mechanisms are systematically investigated. This work not only provides a comprehensive understanding of precipitation behaviors and their impacts on mechanical properties in a Ti-alloyed MEA, but also an interesting phase transformation path for the design of precipitation-hardened HEA/MEAs. • An abnormal L1 2 -LPSO phase transformation occurs in this Ti alloying MEA during aging process. • The abnormal transformation originates from geometrical modification of the compact planes stacking sequences. • The LPSO phase shows a relative weaker strengthening effect and little ductility loss in comparison with L1 2 phase. [ABSTRACT FROM AUTHOR]

An optimization approach based on force density method and mixed integer nonlinear programming is proposed for optimization of tensegrity structures on member connectivities and nodal positions. The member connectivities, nodal coordinates and force densities are simultaneously used as design variables and the number of nodes is the only necessary parameter needed to be given in advance. The proposed approach possesses a general-purpose formulation which can be degenerated into both conversional form-finding formulation and previous member connectivities-finding formulation. Various properties such as the number of cables, nodal coordinates and evenness of member internal forces can be controlled and optimized by introducing appropriate constraints and objective functions. Numerical examples are carried out to verify the proposed approach and illustrate that not only classical tensegrity systems but also novel tensegrity systems can be obtained by the proposed approach. [ABSTRACT FROM AUTHOR]

This study examines how a social pension program changes paid work patterns and expectations about the source of future financial support for the elderly in China. Using the 2011 and 2013 waves of the China Health and Retirement Longitudinal Study (CHARLS), the study finds that the New Rural Pension Program (NRPP) reduced the hours of farmwork and increased the hours of grandchild care among elderly rural men; and both elderly women and men reported less expected reliance on adult children for financial support when they become infirm. These differential effects probably occur because the size of the pension benefit is very small and because of previous gender differences in farmwork and grandchild care. Additionally, the study shows that adult children reduced out-migration and increased their hours spent in farming activities, indicating that the effect of the NRPP has spilled over to younger members of the household. [ABSTRACT FROM AUTHOR]

This study examines the impacts of unpaid family care on labor supply and earnings of women and men near retirement age in urban China. Using the 2011 China Health and Retirement Longitudinal Study (CHARLS) and ordinary least squares (OLS) and instrumental variable approaches, it finds that grandchild care is negatively associated with both women's and men's labor force participation, while there are no effects for eldercare. For women caregivers, caring for grandchildren substantially lowers paid labor hours compared to noncaregivers. No significant relationships are found between eldercare and paid labor hours of women workers. For men workers, neither grandchild care nor eldercare is significantly associated with labor hours. The study also finds no statistically significant relationships between grandchild care and labor earnings for either women or men. Eldercare, however, is positively associated with the earnings of men workers. [ABSTRACT FROM AUTHOR]

In this paper, we propose a hybridly connected structure for hybrid beamforming in millimeter-wave (mmWave) massive MIMO systems, where the antenna arrays at the transmitter and receiver consist of multiple sub-arrays, each of which connects to multiple radio frequency (RF) chains, and each RF chain connects to all the antennas corresponding to the sub-array. In this structure, through successive interference cancelation, we decompose the precoding matrix optimization problem into multiple precoding sub-matrix optimization problems. Then, near-optimal hybrid digital and analog precoders are designed through factorizing the precoding sub-matrix for each sub-array. Furthermore, we compare the performance of the proposed hybridly connected structure with the existing fully and partially connected structures in terms of spectral efficiency, the required number of phase shifters, and energy efficiency. Finally, simulation results are presented to demonstrate that the spectral efficiency of the hybridly connected structure is better than that of the partially connected structure and that its spectral efficiency can approach that of the fully connected structure with the increase in the number of RF chains. Moreover, the proposed algorithm for the hybridly connected structure is capable of achieving higher energy efficiency than existing algorithms for the fully and partially connected structures. [ABSTRACT FROM PUBLISHER]