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For nearly a century, the excessive discharge of organic contaminants has gradually polluted water and endangered people's health, and photocatalysis has been prominently employed to remove persistent recalcitrant organic. Here, MIL‐101(Cr) was firstly employed to introduce thin‐layered Bi2O2CO3 for the formation of Bi2O2CO3/MIL‐101(Cr) nanosheet composite, by a simple and low‐temperature in‐situ growth approach. The phase, morphology, optical, and surface characteristics of the fabricated composite were characterized through XRD, FTIR, SEM‐EDS, N2 adsorption–desorption, UV–Vis DRS, PL, TG, and XPS techniques, and the ability in the photocatalytic breakdown of rhodamine B (RhB) molecule under visible light was also studied. The results of characterization analysis and optical analysis exhibited that Bi2O2CO3/MIL‐101(Cr) has large pore size, good visible light response‐ability, and the heterojunction created by intercalating Bi2O2CO3 on MIL‐101(Cr). Photocatalytic studies revealed that Bi2O2CO3/MIL‐101(Cr) had superior RhB degradation activity than pure MIL‐101(Cr) and Bi2O2CO3, which achieved 97.1% with visible light irradiation for 20 mg/l RhB. Meanwhile, the Bi2O2CO3/MIL‐101(Cr) composite displayed good recyclability after three cycles as revealed by XRD and FTIR analysis proving their excellent stability. This study provides feasible insight into developing novel and efficient MIL‐101‐based heterojunction catalysts for environmental remediation in the future. [ABSTRACT FROM AUTHOR]

Development of an energy‐efficient and economical route is necessary for society to synthesize green biofuels. Herein, cobalt‐doped tungstophosphoric acid (Co‐HPW) is in‐situ impregnated in the Zr‐based metal–organic framework (MOF‐801) forming composite of Co‐HPW/MOF‐801. The chemical composition, morphology, and acidic sites of the Co‐HPW/MOF‐801 composite were analyzed through x‐ray diffractometer (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy‐dispersive x‐ray spectroscopy (EDS), thermogravimetric analysis (TG), N2 physisorption, ammonia temperature‐programmed desorption (NH3‐TPD), pyridine‐adsorbed infrared spectra (Py‐FTIR), and x‐ray photoelectron spectroscopy (XPS). The catalytic performance of the as‐synthesized catalyst was explored to catalyze esterification of lauric acid (LA) with methanol. The outcomes revealed that the Co‐HPW/MOF‐801 nanocatalyst achieved a high conversion of 86.3% under the optimized reaction condition (catalyst amount of 0.15 g, temperature of 100°C, time of 4 h, and methanol/LA molar ratio of 20:1). The excellent catalytical performance is mainly due to the large BET surface area, exposure of more active centers from available pore structure, and simultaneous possession of high Lewis and Brønsted acidity. Furthermore, the kinetic study revealed that the reaction process was kinetically controlled and the activation energy was found to be 42.1 kJ/mol. The results suggest that the synthesized Co‐HPW/MOF‐801 nanocatalyst is an environmental greenness, low cost, and suitable for easy scale‐up for the production of biofuels. [ABSTRACT FROM AUTHOR]

The existing methods to determine the cognitive function level of end‐stage renal disease (ESRD) are not only inaccurate but also susceptible to the influence of the patient's education level, emotional state, and examination environment. We proposed a global iterative optimization framework (GIO) to accurately predict cognitive function statuses of ESRD patients without being affected by the above factors. First, the functional magnetic resonance imaging (fMRI) data preprocessed and the time series were extracted to construct brain functional networks. Secondly, the areas under curve (AUC) of topological attribute parameters in the brain functional networks were extracted as features. After statistical analysis, the global efficiency, the characteristic path length, and the shortest path length in the small‐world network were selected as features for linear fusion. Finally, the support vector regression (SVR) was used as the basis of GIO framework, and the global iterative search strategy was introduced to find out the most appropriate penalty factor and radial basis function parameters. Achieving the objective of accurately predicting the cognitive function status of patients with end‐stage renal disease. Since this framework uses SVR which has special advantages in processing small sample data, and introduces appropriate parameter selection method, the prediction ability of GIO framework has been significantly improved. Experimental results demonstrate that the final prediction accuracy of the proposed framework is significantly better than those of SVR, LSSVR, GMO‐SVR, GMO‐LSSVR, and PSO‐SVR. The mean absolute error (MAE) and the mean absolute percentage error (MAPE) of the proposed framework are 0.55% and 2.58%, respectively. It is suggested that this framework is more convenient to determine the current level of cognitive function in ESRD patients and is conducive to the early prevention of cognitive dysfunction in ESRD patients. [ABSTRACT FROM AUTHOR]

The power system dynamics have consistently challenged the rapid and persistent proliferation of photovoltaic (PV) systems in power systems. In this paper, the authors propose the generalized discrete‐time equivalent model (GDEM) of PV power generation system using a fourth‐order dynamic equivalent model for representing the physical characteristics of PV power stations in power system dynamic studies. In addition, the authors propose a grid‐connected system model which includes modelling interfaces (MIs) for the GDEM of power grid and the GDEM of PV power generation system in dynamic studies. The proposed equivalent models of the power grid and PV power generation system will improve the simulation accuracy and speed in dynamic power system studies. The authors have used the IEEE 14‐bus system and simulated various types of short‐circuit faults and PV penetration levels in their study to demonstrate the merits of the proposed GDEM of grid‐connected system in power systems. The pertinent simulation results are analyzed and conclusions are presented. [ABSTRACT FROM AUTHOR]

Photocaging holds promise for the precise manipulation of biological events in space and time. However, current near‐infrared (NIR) photocages are oxygen‐dependent for their photolysis and lack of timely feedback regulation, which has proven to be the major bottleneck for targeted therapy. Herein, we present a hypoxia‐dependent photo‐activation mechanism of dialkylamine‐substituted cyanine (Cy‐NH) accompanied by emissive fragments generation, which was validated with retrosynthesis and spectral analysis. For the first time, we have realized the orthogonal manipulation of this hypoxia‐dependent photocaging and dual‐modal optical signals in living cells and tumor‐bearing mice, making a breakthrough in the direct spatiotemporal control and in vivo feedback regulation. This unique photoactivation mechanism overcomes the limitation of hypoxia, which allows site‐specific remote control for targeted therapy, and expands the photo‐trigger toolbox for on‐demand drug release, especially in a physiological context with dual‐mode optical imaging under hypoxia. [ABSTRACT FROM AUTHOR]

A miniaturized high gain dipole array antenna for 2.4/5 GHz wireless local area network (WLAN) applications (2.4‐2.5/5.15‐5.85 GHz) is proposed in this paper. The proposed antenna is composed of a 1 × 3 dipole array, a U‐shaped branch, and a double‐layer feedline. Dual‐band operation is realized by using a double‐branch dipole. The peak gain of the proposed dipole array antenna is improved due to the in‐phase current distributions on dipole elements. A U‐shaped branch is added to further enhance the peak gain in the lower band. For miniaturization, the half‐cutting method is applied. One prototype of the proposed miniaturized antenna with a size of 168 × 10.5 × 0.6 mm3 is manufactured and measured. As a result, the proposed antenna provides the operating bands of 2.30 to 2.59 GHz and 5.10 to 6.73 GHz (voltage standing wave ratio ≤ 2), fully covering 2.4/5 GHz WLAN band. Over the lower/higher band, the peak gain and efficiency are higher than 4.2/5 dBi and 58%/49%, respectively. Furthermore, good omnidirectional radiation characteristic in the horizontal plane is achieved. [ABSTRACT FROM AUTHOR]

SUMMARY: Rhamnogalacturonan‐II (RG‐II) is structurally the most complex glycan in higher plants, containing 13 different sugars and 21 distinct glycosidic linkages. Two monomeric RG‐II molecules can form an RG‐II‐borate diester dimer through the two apiosyl (Api) residues of side chain A to regulate cross‐linking of pectin in the cell wall. But the relationship of Api biosynthesis and RG‐II dimer is still unclear. In this study we investigated the two homologous UDP‐D‐apiose/UDP‐D‐xylose synthases (AXSs) in Arabidopsis thaliana that synthesize UDP‐D‐apiose (UDP‐Api). Both AXSs are ubiquitously expressed, while AXS2 has higher overall expression than AXS1 in the tissues analyzed. The homozygous axs double mutant is lethal, while heterozygous axs1/+ axs2 and axs1 axs2/+ mutants display intermediate phenotypes. The axs1/+ axs2 mutant plants are unable to set seed and die. By contrast, the axs1 axs2/+ mutant plants exhibit loss of shoot and root apical dominance. UDP‐Api content in axs1 axs2/+ mutants is decreased by 83%. The cell wall of axs1 axs2/+ mutant plants is thicker and contains less RG‐II‐borate complex than wild‐type Col‐0 plants. Taken together, these results provide direct evidence of the importance of AXSs for UDP‐Api and RG‐II‐borate complex formation in plant growth and development. Significance Statement: This paper investigates the function of AXS in Arabidopsis. We emphasize the crucial role of AXS in plant development and reproduction by controlling UDP‐Api content to regulate RG‐II‐borate complex levels. [ABSTRACT FROM AUTHOR]

Chemiluminescence (CL)‐based technologies have revolutionized in vivo monitoring of biomolecules. However, significant technical hurdles have limited the achievement of trigger‐controlled, bright, and enriched CL signal. Herein, a dual‐lock strategy uses sequence‐dependent triggers for bright optical imaging with real‐time fluorescent signal and ultra‐sensitive CL signal. These probes can obtain an analyte‐triggered accumulation of stable pre‐chemiluminophore with aggregation‐induced emission (AIE), and then the pre‐chemiluminophore exhibits a rapid photooxidation process (1,2‐dioxetane generation) by TICT‐based free‐radical addition, thereby achieving an enrichment and bright CL signal. The dual‐lock strategy expands the in vivo toolbox for highly accurate analysis and has for the first time allowed access to accurately sense and trace biomolecules with high‐resolution, dual‐mode of chemo‐fluoro‐luminescence, and three‐dimensional (3D) imaging in living animals. [ABSTRACT FROM AUTHOR]

A joint target detection and tracking method based on plot-track quality evaluation (PTQE-D&T) is proposed here. The presented method consists of three consecutive steps. First, a set of candidate plots is extracted from the Detector and Plot-Extractor, where the plot quality is calculated simultaneously based on multi-dimensional echoes constituting the plot. Then, a track-before-detect (TBD) processor based on dynamic programming (DP) is utilised to jointly elaborate the observations from multiple scans and outputs potential tracks to be confirmed. Finally, a confirmation strategy is introduced via plot-track quality evaluation. Experimental results are provided to demonstrate the effectiveness of the proposed method, where two data sets collected from a ground-based surface-search radar and a ship borne 3D radar are used. Moreover, the proposed PTQE-D&T structure is totally consistent with conventional radar data processing architecture, meaning that it is promising in engineering applications. [ABSTRACT FROM AUTHOR]

CLE peptides have been implicated in various developmental processes of plants and mediate their responses to environmental stimuli. However, the biological relevance of most CLE genes remains to be functionally characterized. Here, we report that CLE9, which is expressed in stomata, acts as an essential regulator in the induction of stomatal closure. Exogenous application of CLE9 peptides or overexpression of CLE9 effectively led to stomatal closure and enhanced drought tolerance, whereas CLE9 loss‐of‐function mutants were sensitivity to drought stress. CLE9‐induced stomatal closure was impaired in abscisic acid (ABA)‐deficient mutants, indicating that ABA is required for CLE9‐medaited guard cell signalling. We further deciphered that two guard cell ABA‐signalling components, OST1 and SLAC1, were responsible for CLE9‐induced stomatal closure. MPK3 and MPK6 were activated by the CLE9 peptide, and CLE9 peptides failed to close stomata in mpk3 and mpk6 mutants. In addition, CLE9 peptides stimulated the induction of hydrogen peroxide (H2O2) and nitric oxide (NO) synthesis associated with stomatal closure, which was abolished in the NADPH oxidase‐deficient mutants or nitric reductase mutants, respectively. Collectively, our results reveal a novel ABA‐dependent function of CLE9 in the regulation of stomatal apertures, thereby suggesting a potential role of CLE9 in the stress acclimatization of plants. CLE peptides have been implicated in various developmental processes of plants and mediate their responses to environmental stimuli. Here, we reported an essential role of CLE9 in the induction of stomatal closure. CLE9 stimulated stomatal closure in an ABA‐dependent manner, accompanied with H2O2/NO production. Further investigation revealed that OST1, SLAC1, and MPK3/MPK6 are required for CLE9‐mediated guard cell signalling. [ABSTRACT FROM AUTHOR]

Abstract: Laboratorial experiments of coal spontaneous combustion under non‐isothermal conditions were conducted using a self‐made instrument aimed at investigating the characteristics of carbon monoxide emissions and kinetic characteristics. The impacts of coal rank, particle size, and oxygen content on the CO production during the decaying process of spontaneous combustion were studied. The experimental results demonstrated that coal particle size had a significant influence on the spontaneous combustion at high temperatures and coals of a large particle size decreased slowly in terms of the total CO production. Meanwhile, it is also found that even if the oxygen content was as low as 3 %, the oxidation reaction of coal still existed, liberating CO and heat at the same time. Therefore, stricter standards were recommended when judging whether or not a spontaneous combustion had been extinguished in gobs. Additionally, the studies on oxidation kinetics of coal implied that the activation energy was dependent both on the oxidation temperatures and coal properties. Oxidation temperatures affect the magnitude of activation energy, while coal properties impact the response of activation energy to the oxygen contents. [ABSTRACT FROM AUTHOR]

Accumulating data indicate that strigolactones ( SLs) are implicated in the response to environmental stress, implying a potential effect of SLs on stomatal response and thus stress acclimatization. In this study, we investigated the molecular mechanism underlying the effect of SLs on stomatal response and their interrelation with abscisic acid ( ABA) signaling., The impact of SLs on the stomatal response was investigated by conducting SL-feeding experiments and by analyzing SL-related mutants. The involvement of endogenous ABA and ABA-signaling components in SL-mediated stomatal closure was physiologically evaluated using genetic mutants. Pharmacological and genetic approaches were employed to examine hydrogen peroxide (H2O2) and nitric oxide ( NO) production., SL-related mutants exhibited larger stomatal apertures, while exogenous SLs were able to induce stomatal closure and rescue the more widely opening stomata of SL-deficient mutants. The SL-biosynthetic genes were induced by abiotic stress in shoot tissues. Disruption of ABA-biosynthetic genes, as well as genes that function in guard cell ABA signaling, resulted in no impairment in SL-mediated stomatal response. However, disruption of MORE AXILLARY GROWTH2 ( MAX2), DWARF14 ( D14), and the anion channel gene SLOW ANION CHANNEL-ASSOCIATED 1 (SLAC1) impaired SL-triggered stomatal closure. SLs stimulated a marked increase in H2O2 and NO contents, which is required for stomatal closure., Our results suggest that SLs play a prominent role, together with H2O2/ NO production and SLAC1 activation, in inducing stomatal closure in an ABA-independent mechanism. [ABSTRACT FROM AUTHOR]

The tectonic evolution of South Qinling, which is a main part of the Qinling orogenic belt, is still in dispute and deformation history of South Qinling is poorly studied. In this paper, detailed structural, microstructural, quartz c-axis fabric analysis, and geochronology results for the Madao gneiss in South Qinling are presented to characterize the deformation history. Results show that rocks in the northern part (Tiefodian-Laozhanggou) experience general shearing and deform at relative low temperature. The shear sense generally is south to north. In contrast, rocks in the southern part (Laozhanggou-Panjiahe) are weakly sheared with pure shear features and evidence of high-temperature deformation. Based on the analyses, we conclude that there exist two distinct deformation geometries in the Madao gneiss and accordingly we can divide the deformation into two stages. The early stage is represented by regional shortening, while the late stage features northward thrust shearing and evidence shows that it was a progressive process between them. LA-ICP MS U-Pb dating of zircons from pre-deformational migmatite veins yields age of 198.5 ± 2.0 Ma. This result, in combination with the age of post-deformational granite, indicates that the northward thrust shearing of the Madao gneiss occurred in the Late Triassic. In view of these results and other reported data in South Qinling, we propose that deformation in Madao gneiss may result from the initial collision and subsequent northward accretion in Late Triassic. [ABSTRACT FROM AUTHOR]

There are wide spread Cenozoic volcanic rocks in Tengchong ( CVRT), Yunnan province, SW China. These rocks comprise three rock types: basalt, andesite (dominant type) and dacite. Most samples are sub-alkaline, and among the sub-alkaline rocks, most are high- K calc-alkaline. These rocks have a SiO2 range of 49.1 wt.% to 66.9 wt.%. TiO2 contents are not high and have a variation of 0.7 wt.%-1.6 wt.%. Trace element concentrations and element ratios (such as Nb/ U, Ce/ Pb, Nb/ La, etc.) of these rocks have a large variation. 87Sr/ 86Sr values fall in the range of 0.7057-0.7093 and 143Nd/ 144Nd values change from 0.5120 to 0.5125. 206Pb/ 204Pb, 207Pb/ 204Pb, and 208Pb/ 204Pb ratios are in the range of 17.936-19.039, 15.614-15.810, and 38.894-39.735, respectively. These geochemical characteristics of CVRT make them resemble island-arc volcanic rocks. We suggest that the magmas were generated in the lithospheric mantle that had already been metasomatized by previous subduction processes. By the study of the uplift history of the Tibetan Plateau, we found that the beginning of the geotectonic processes to the eruption of CVRT was coeval with one uplift event. Therefore, we propose that the uplift of the Tibetan Plateau caused collapse of the collisional orogeny in Tengchong, which further triggered the generation and eruption of the CVRT magmas. [ABSTRACT FROM AUTHOR]