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We synthesized BiVO4 mesocrystals with ordered assembly structure, and studied the structural order and the relationship between the photodegradation of Rhodamine B. Au nanoparticles (NPs) were successfully loaded onto Meso-BiVO4 by light-assisted induction, and Cd nanoparticles were further selected to be deposited on Au nanoparticles to form Z-scheme photocatalyst Meso-BiVO4-Au-CdS heterostructures. We try and propose to analyze its ordered assembly structure by XRD for the first time. The results show that Meso-BiVO4 is a mesocrystal with highly exposed (001) plane and directional assembly structure. The charge separation efficiency of all samples was studied by PL spectroscopy. The results show that the Z-scheme Meso-BiVO4-Au-CdS can promote the charge separation and obtain the best carrier separation efficiency. Thus, it has the best photocatalytic activity in the experiment of photocatalytic degradation of rhodamine B. The main active species in the degradation process were confirmed by free radical trapping experiment, and the degradation mechanism was put forward. [ABSTRACT FROM AUTHOR]

Membrane proteins are critical to biological processes and central to life sciences and modern medicine. However, membrane proteins are notoriously challenging to study, mainly owing to difficulties dictated by their highly hydrophobic nature. Previously, we reported QTY code, which is a simple method for designing water-soluble membrane proteins. Here, we apply QTY code to a transmembrane receptor, histidine kinase CpxA, to render it completely water-soluble. The designed CpxAQTY exhibits expected biophysical properties and highly preserved native molecular function, including the activities of (i) autokinase, (ii) phosphotransferase, (iii) phosphatase, and (iv) signaling receptor, involving a water-solubilized transmembrane domain. We probe the principles underlying the balance of structural stability and activity in the water-solubilized transmembrane domain. Computational approaches suggest that an extensive and dynamic hydrogen-bond network introduced by QTY code and its flexibility may play an important role. Our successful functional preservation further substantiates the robustness and comprehensiveness of QTY code. Membrane proteins play essential roles in biological processes but are very difficult to study due to their hydrophobic nature. Here, the authors apply the QTY code, a method for designing water soluble membrane proteins, to histidine kinase CpxA to render it completely water-soluble and preserve the native molecular function. [ABSTRACT FROM AUTHOR]

We studied a method to prepare a novel titanium dioxide (TiO2) composite photocatalyst, starting from improving the separation efficiency of photogenerated electrons and holes. Regular TiO2 microspheres were prepared by sol-gel method and loaded onto Ti3C2Tx (Mxene). The high electrical conductivity of Mxene was utilized to transfer photogenerated electrons quickly and effectively prevent their recombination. By adjusting the addition amount of Mxene, the hydrogen production efficiency of the sample was greatly improved, and the maximum efficiency reached 135.2 µmol·g−1·h−1, which was twice that of pure TiO2. The nanocomposites were characterized by XRD, PL, TEM and SEM analysis and electrochemical methods, and the test proved that the improvement of hydrogen production efficiency was caused by the improvement of the separation efficiency of photogenerated electrons and holes. This work demonstrates the application of Mxene as a catalyst to improve efficiency and broadens the application prospects of Mxene. [ABSTRACT FROM AUTHOR]

Escalators are a widely used means of transportation. The escalator truss structure is subjected to random loads during working operation, and fatigue failure of escalator truss structure occurs from time to time. In this study, the pedestrian load time history of escalator in a subway station was counted by means of real measurements. The stability of the collected data was verified by the round-trip test method. By using rain-flow counting method to process the load time history, the random load spectrum of escalator structure was obtained. And the eight-level fatigue load spectrum of escalator truss was simplified. To study the probabilistic characteristics of the truss material, the P-S-N curve of the truss material was obtained based on the subsample method and modified to obtain the P-S-N curve of the truss structure. Finally, the fatigue life of the dangerous part of the escalator truss structure was predicted by using Miner liner fatigue accumulation damage theory. The probabilistic life of the truss structure was obtained. Based on the finite element simulation analysis, the fatigue life of the truss structure is verified, and the results show that the simulation results are basically consistent with the calculation results, which proves the effectiveness of the method of this paper. [ABSTRACT FROM AUTHOR]

Scintillators that exhibit X-ray-excited luminescence have great potential in radiation detection, X-ray imaging, radiotherapy, and non-destructive testing. However, most reported scintillators are limited to inorganic or organic crystal materials, which have some obstacles in repeatability and processability. Here we present a facile strategy to achieve the X-ray-excited organic phosphorescent scintillation from amorphous copolymers through the copolymerization of the bromine-substituted chromophores and acrylic acid. These polymeric scintillators exhibit efficient X-ray responsibility and decent phosphorescent quantum yield up to 51.4% under ambient conditions. The universality of the design principle was further confirmed by a series of copolymers with multi-color radioluminescence ranging from green to orange-red. Moreover, we demonstrated their potential application in X-ray radiography. This finding not only outlines a feasible principle to develop X-ray responsive phosphorescent polymers, but also expands the potential applications of polymer materials with phosphorescence features. The authors achieved the X-ray-excited organic phosphorescent scintillation from copolymers through copolymerization of bromine-substituted chromophores and acrylic acid and demonstrated their potential application in X-ray radiography. [ABSTRACT FROM AUTHOR]

In big power systems, the distribution transformer plays a key role in determining the power flow. Higher power system efficiency and improved power transfer capacity are implied by their improved performance. However, numerous distribution transformer failures in the recent past have disrupted the power supply and attracted a lot of interest from electrical experts. This research proposes novel technique in optimization of distribution transformer based on maximum probability in load with fault assessment based on artificial enabled communications in optimization for transactive energy framework using Nissan Leaf BEVs with a 24-kWh battery capacity which were utilized in the test system. Here, the load distribution of transformer has been carried out using maximum probability, and load distribution-based fault detection is carried out using regressive reinforcement Boltzmann neural network. Additionally, it is shown how the load distribution affects the needed amplitude of the second harmonic component of the circulating currents, which can be used to assure balancing capabilities within each MMC arm. Experimental analysis has been carried out in terms of load balancing, RMSE, MAPE, reliability, energy storage, and voltage drop. The proposed technique attained load balancing of 77%, RMSE of 69%, MAPE of 77%, reliability of 93%, energy storage of 97%, and voltage drop of 96%. [ABSTRACT FROM AUTHOR]

Carbon sequestration is an indispensable ecosystem service provided by soil and vegetation, so mapping and valuing the carbon budget by considering both ecological and social factors is an important trend in evaluating ecosystem services. In this work, we established multiple scenarios to evaluate the impacts of land use change, population growth, carbon emission per capita, and carbon markets on carbon budget. We quantified carbon sinks (aboveground and belowground) under different scenarios, using the Carnegie-Ames-Stanford Approach (CASA) model and an improved carbon cycle process model, and studied carbon sources caused by human activities by analyzing the spatial distribution of human population and carbon emission per capita. We also assessed the net present value (NPV) for carbon budgets under different carbon price and discount rate scenarios using NPV model. Our results indicate that the carbon budget of Guanzhong-Tianshui Economic Region is surplus: Carbon sinks range from 1.50 × 10 to 1.54 × 10 t, while carbon sources caused by human activities range from 2.76 × 10 to 7.60 × 10 t. And the NPV for carbon deficits range from 3.20 × 10 RMB to 1.52 × 10 RMB. From the perspective of ecological management, deforestation, urban sprawl, population growth, and excessive carbon consumption are considered as the main challenges in balancing carbon sources and sinks. Levying carbon tax would be a considerable option when decision maker develops carbon emission reduction policies. Our results provide a scientific and credible reference for harmonious and sustainable development in the Guanzhong-Tianshui Economic Region of China. [ABSTRACT FROM AUTHOR]

An ordering of the Sr cations over two crystallographic sites exists in F-modified aluminosilicate with composition of SrAlSiOF (SASF), opening opportunity to customize the local crystal accommodation environment for activators upon solid solution of Ba or Ca for Sr cations. A series of SrMAlSiOF:Ce (M = Ba, Ca) phosphors are synthesized by high temperature solid-state reaction method, and the dependence of luminescent properties and thermal stability on the solid solution contents of alkaline-earth metals are investigated in this work. The preferable substitution sites of Ba and Ca and the resultant influence on the local crystal structure of Ce and the performances of phosphors were discussed in detail. [ABSTRACT FROM AUTHOR]

BES1 and BZR1 were originally identified as two key transcription factors specifically regulating brassinosteroid (BR)-mediated gene expression. They belong to a family consisting of six members, BES1, BZR1, BEH1, BEH2, BEH3, and BEH4. bes1 and bzr1 single mutants do not exhibit any characteristic BR phenotypes, suggesting functional redundancy of these proteins. Here, by generating higher order mutants, we show that a quintuple mutant is male sterile due to defects in tapetum and microsporocyte development in anthers. Our genetic and biochemical analyses demonstrate that BES1 family members also act as downstream transcription factors in the EMS1-TPD1-SERK1/2 pathway. Ectopic expression of both TPD1 and EMS1 in bri1-116, a BR receptor null mutant, leads to the accumulation of non-phosphorylated, active BES1, similar to activation of BES1 by BRI1-BR-BAK1 signaling. These data suggest that two distinctive receptor-like kinase-mediated signaling pathways share BES1 family members as downstream transcription factors to regulate different aspects of plant development. BES1 and BZR1 transcription factors are activated by the BRI1-BAK1 receptor complex during brassinosteroid signaling. Here the authors show that BES1-family members also act in anthers, downstream of another receptor-like kinase-mediated signaling pathway, EMS1-TPD1-SERK1/2, to promote tapetum development. [ABSTRACT FROM AUTHOR]

Enhanced sampling methods such as metadynamics and umbrella sampling have become essential tools for exploring the configuration space of molecules and materials. At the same time, they have long faced a number of issues such as the inefficiency when dealing with a large number of collective variables (CVs) or systems with high free energy barriers. Here we show that, with clustering and adaptive tuning techniques, the reinforced dynamics (RiD) scheme can be used to efficiently explore the configuration space and free energy landscapes with a large number of CVs or systems with high free energy barriers. We illustrate this by studying various representative and challenging examples. First we demonstrate the efficiency of adaptive RiD compared with other methods and construct the nine-dimensional (9D) free energy landscape of a peptoid trimer, which has energy barriers of more than 8 kcal mol -1 . We then study the folding of the protein chignolin using 18 CVs. In this case, both the folding and unfolding rates are observed to be 4.30 μs -1 . Finally, we propose a protein structure refinement protocol based on RiD. This protocol allows us to efficiently employ more than 100 CVs for exploring the landscape of protein structures and it gives rise to an overall improvement of 14.6 units over the initial global distance test-high accuracy (GDT-HA) score., (© 2021. The Author(s), under exclusive licence to Springer Nature America, Inc.)