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Biodiversity in tropical regions is facing threats from agricultural expansion and intensification. Therefore, a promising future for local ecosystem conservation depends not only on traditional protected areas but also on well‐managed agricultural landscapes. In this study, we compared the ecological traits of bird species in paddy fields outside of protected areas and natural forests within the protected areas of Xishuangbanna, southern China. There were 148 species in total, of which 98 were in forests and 55 in paddy fields. The abundance of birds in paddy fields was 176 per kilometer, which was much higher than the 60 per kilometer in forests. There were 26 law‐protected species observed, half of which were found in each habitat. The main functional groups living in nature reserves are invertivores and frugivores, whereas paddy fields provide habitats for aquatic predator and granivore bird species. Our results indicate that paddy fields act as a refuge for wetland and grassland bird species when natural wetlands disappear, highlighting the urgent need to focus more on wetland protection and eco‐friendly agricultural schemes at the landscape scale in future conservation policies. [ABSTRACT FROM AUTHOR]

Organic molecular field‐effect transistors (FETs) are promising building components for future electronic circuits. Efficient control of charge transport properties is one key issue in the design of organic molecular FETs. In this study, we propose a redesign of a naphthalene‐based FET by introducing two azulene components in opposite dipole moment directions. Using density functional theory combined with non‐equilibrium Green's function, the simulated electronic transport characteristics reveal that the introduction of polar azulene components effectively narrows the frontier molecular orbitals gap, leading to an increase in the ON‐state current. Meanwhile, the OFF‐state current is significantly suppressed by highly localizing the dominant electronic transport channel. As a result, improved gate controllability is achieved with a higher ON‐OFF current ratio, which is nearly seven times higher than that of the naphthalene‐based FET device. These findings provide theoretical directions for future design of organic molecular FET devices with enhanced gating regulation efficiency. [ABSTRACT FROM AUTHOR]

Food preservation is a critical issue in ensuring food safety and quality. Growing concern around industrial pollution of food and demand for environmentally sustainable food has led to increased interest in developing effective and eco‐friendly preservation techniques. Gaseous ClO2 has gained attention for its strong oxidizing properties, high efficacy in microorganism inactivation, and potential for preserving the attributes and nutritional quality of fresh food while avoiding the formation of toxic byproducts or unacceptable levels of residues. However, the widespread use of gaseous ClO2 in the food industry is limited by several challenges. These include large‐scale generation, high cost and environmental considerations, a lack of understanding of its mechanism of action, and the need for mathematical models to predict inactivation kinetics. This review aims to provide an overview of the up‐to‐date research and application of gaseous ClO2. It covers preparation methods, preservation mechanisms, and kinetic models that predict the sterilizing efficacy of gaseous ClO2 under different conditions. The impacts of gaseous ClO2 on the quality attributes of fresh produce and low‐moisture foods, such as seeds, sprouts, and spices, are also summarized. Overall, gaseous ClO2 is a promising preservation approach, and future studies are needed to address the challenges in large‐scale generation and environmental considerations and to develop standardized protocols and databases for safe and effective use in the food industry. [ABSTRACT FROM AUTHOR]

Recognizing the emergency of the global climate issue, the current fossil fuel‐based economic structure with massive carbon emission is urgent to be transformed. Catalytic conversion of COx, as an emerging alternative technology to produce advanced chemicals and fuels, has received enormous attention. Particularly, photothermal COx conversion, combining the advantages of high efficiency and low pollution, has shown the potential for the production of solar fuels and chemicals, and the progress of this field is accelerating. This review summarizes the fundamentals of photothermal catalysis as well as the state‐of‐the‐art advances of the photothermocatalytic COx conversion in the three main parts that involve COx hydrogenation, water–gas shift reaction, and CO2 reforming of CH4. Moreover, the challenges and perspectives are also briefly discussed, which proposes guidance for future investigation of photothermal C1 conversion and anthropogenic carbon cycle. [ABSTRACT FROM AUTHOR]

Advances in achieving high external quantum efficiency (EQE) of near‐infrared (NIR) organic light‐emitting diodes (OLEDs) are lagging behind that of the visible‐light OLEDs, according to the energy gap law. Herein, two structurally simple NIR‐phosphorescent Ir(III) complexes, DTCNIr and PTCNIr, with the cyclometalated ligands functionalized by the 1‐phenylisoquinoline‐4‐carbonitrile moiety and thieno/benzo[b]thiophene moiety are handily accessed within three synthetic steps. The introduction of the cyano unit can significantly lower the lowest unoccupied molecular orbitals whereas incorporating the conjugated group can elevate the highest occupied molecular orbitals of the newly designed Ir(III) complexes. The intramolecular charge transfer (ICT) transitions are enhanced due to the increased donor–acceptor interaction inside the metallophosphor. As a result, the emissions are red‐shifted to the NIR region with fast radiative decay. A maximum external quantum efficiency (EQE) of 8.11% with the emission peak at 726 nm for DTCNIr and a maximum EQE of 6.39% with the emission peak at 763 nm for PTCNIr are achieved in the NIR OLEDs by using these Ir(III) materials as the dopant emitters, a champion efficiency in the Ir(III)‐based OLEDs with the emission peak exceeding 760 nm. [ABSTRACT FROM AUTHOR]

With the development of device miniaturization, traditional Si‐based field effect transistors (FETs) are approaching their scaling limits. It is necessary to find more alternative materials to improve the performance of FETs. 2D semiconductors attract great attention for channel material due to their atomic‐scale smoothness and dangling‐bond‐free surface, and the gate electrostatic properties and charge carrier mobility are better than traditional 3D Si‐based semiconductor. In this paper, using density functional theory combined with nonequilibrium Green's function formalism, the electronic properties and device performance of sub‐5 nm monolayer SiMe‐graphene n‐type field‐effect transistors are evaluated. Remarkably, the on‐state current value of the FET can reach 3070 µA µm−1, which greatly surpasses most of reported FETs based on other 2D semiconductors. In addition, the on‐state current, power dissipation, and delay time of the SiMe‐graphene FETs satisfy the high‐performance requirements of the 2020 International Roadmap for Device and Systems under different supply voltages, which indicates that the FETs can work at different operating frequencies and power consumption. Moreover, via controlling electrode doping concentration, the channel length can be reduced to 4 nm. In total, the SiMe‐graphene is a favorable channel material for future FETs devices. [ABSTRACT FROM AUTHOR]

Background: Congenital hydrocephalus is one of the symptoms of Walker–Warburg syndrome that is attributed to the disruptions of the genes, among which the B3GALNT2 gene is rarely reported. A diagnosis of the Walker–Warburg syndrome depends on the clinical manifestations and the whole‐exome sequencing after birth, which is unfavorable for an early diagnosis. Methods: Walker–Warburg Syndrome was suspected in two families with severe fetal congenital hydrocephalus. Whole‐exome sequencing and Sanger sequencing were performed on the affected fetuses. Results: The compound heterozygous variants c.1A>G p.(Met1Val) and c.1151+1G>A, and c.1068dupT p.(D357*) and c.1052 T>A p.(L351*) in the B3GALNT2 gene were identified, which were predicted to be pathogenic and likely pathogenic, respectively. Walker–Warburg syndrome was prenatally diagnosed on the basis of fetal imaging and whole‐exome sequencing. Conclusions: Our findings expand the spectrum of pathogenic mutations in Walker–Warburg syndrome and provide new insights into the prenatal diagnosis of the disease. [ABSTRACT FROM AUTHOR]

Single‐molecule electronics is a promising solution for electronic device miniaturization. While controllable molecular logic gates are particularly attractive because they are the primary element and can accomplish logical operation reliable and repeatedly for practical application. Here, a brand‐new molecule, which is constructed from a light‐switchable azobenzene unit and proton‐switchable pyrimidine unit, is reported. The electronic transport properties of the molecule are theoretically investigated by density functional theory (DFT) combined with non‐equilibrium Green's function method (NEGF). The calculated current–voltage curves show that the molecule system produces a low resistance only when the ultraviolet (UV) light and acid solution are applied, otherwise, a high resistance will be obtained. Therefore, the molecule system can behave as a single‐molecule AND logic gate which can be controlled by two orthogonal inputs: protonation and light. This work demonstrates a feasible perspective for creating single‐molecule logic gate device. [ABSTRACT FROM AUTHOR]

The anti‐permeability of an alkyd coating was modified by controlled airflow during the curing process. After the immersion test, the thinner airflow‐modified region had the best anti‐permeability compared with other thicker regions. The abnormal permeation behavior could be attributed to the difference in air pressure caused by the airflow. A model involving solvent evaporation and defect formation processes was proposed to interpret the airflow affected abnormal permeation behavior. This defect modification method may be employed to improve the corrosion resistance of an alkyd coating in a selected area and improve the painting quality in practice. [ABSTRACT FROM AUTHOR]

By employing spin‐polarized density functional theory (DFT) combined with non‐equilibrium Green's function technique (NEGF), we have investigated the spin transport properties of a series of manganese diporphyrins (MnDPs) with different torsion angle (θ=0°, 10°, 20°, 30°, 40°, 50°, 60°). It is found that the spin transport properties of molecular junctions can be modulated by mechanical tuning of different dihedral angle. In addition, the molecular junctions have characterized Giant magnetoresistance (GMR), spin filtering effect (SFE) and negative differential resistance (NDR). More interestingly, our results show that the MR could reach over 14000 % at low bias voltage, and nearly perfect spin filtering efficiency can be obtained when the torsion angle θ=20°. The numerical analysis reveals that the matching of PDOS for two parts of MnDP molecule is the physical mechanism which is causing the appearance of GMR in the low bias voltage. Our findings might be useful for the application of MnDP‐based molecular devices. Molecular electronics: the ability to manipulate electron spin in organic molecular materials offers a new and tantalizing route towards spin electronics. The spin transport properties of molecular junctions can be modulated by mechanical tuning of different dihedral angles. A giant magnetoresistance (over 14000 %) is found under low bias voltage and that can be engineered by an appropriate choice of different dihedral angles. [ABSTRACT FROM AUTHOR]

DEP domain containing 1 (DEPDC1) protein is a novel oncoantigen upregulated in multiple types of cancers which present oncogenic activity and high immunogenicity. However, the function and therapeutic potential of DEPDC1 in hepatocellular carcinoma (HCC) remain unclear. In the present study, we showed that DEPDC1 was frequently upregulated in HCC and associated with cancer diagnosis and poor prognosis for HCC patients. Moreover, DEPDC1 promotes HCC cell proliferation in vitro as well as carcinogenesis in vivo. Notably, DEPDC1 overexpression also increases the neoplasm metastasis ability of HCC cells both in vivo and in vitro. Gene set enrichment analysis results showed that DEPDC1 expression is positively correlated with K‐RAS signal pathway, pathways in cancer and WNT/β‐catenin signal pathway, all of which are closely associated with specific cancer‐related gene sets. Our study provides the basis for further investigation of the molecular mechanism by which DEPDC1 promotes the development and metastasis of HCC. High expression level of DEPDC1 in HCC promotes tumor cell proliferation and metastasis and can serve as a biomarker for HCC diagnosis and prognostic evaluation. [ABSTRACT FROM AUTHOR]

Here, we report a highly water‐soluble colorimetric and fluorescent pH probe that works in the pH range 0.2–3.0. The probe showed a rapid response, high stability, and excellent reversibility to acidity. Moreover, the fluorescence of probe was not influenced by the existence of high concentration of cations. The pKa of probe was calculated to be 2.25 ± 0.06. Furthermore, the pH test papers coated with the probe exhibited a distinct color change in acidic conditions. [ABSTRACT FROM AUTHOR]

Detailed understandings of the reaction mechanisms of RNA catalysis in various environments can have profound importance for many applications, ranging from the design of new biotechnologies to the unraveling of the evolutionary origin of life. An integral step in the nucleolytic RNA catalysis is self-cleavage of RNA strands by 2′- O-transphosphorylation. Key to elucidating a reaction mechanism is determining the molecular structure and bonding characteristics of transition state. A direct and powerful probe of transition state is measuring isotope effects on biochemical reactions, particularly if we can reproduce isotope effect values from quantum calculations. This article significantly extends the scope of our previous joint experimental and theoretical work in examining isotope effects on enzymatic and nonenzymatic 2′- O-transphosphorylation reaction models that mimic reactions catalyzed by RNA enzymes (ribozymes), and protein enzymes such as ribonuclease A (RNase A). Native reactions are studied, as well as reactions with thio substitutions representing chemical modifications often used in experiments to probe mechanism. Here, we report and compare results from eight levels of electronic-structure calculations for constructing the potential energy surfaces in kinetic and equilibrium isotope effects (KIE and EIE) computations, including a 'gold-standard' coupled-cluster level of theory [CCSD(T)]. In addition to the widely used Bigeleisen equation for estimating KIE and EIE values, internuclear anharmonicity and quantum tunneling effects were also computed using our recently developed ab initio path-integral method, that is, automated integration-free path-integral method. The results of this work establish an important set of benchmarks that serve to guide calculations of KIE and EIE for RNA catalysis. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Nitrogen isotopes provide integrated information about nitrogen cycling in terrestrial ecosystems. This study explores the regional patterns of ecosystem 15N abundance along a 1200 km transect in Inner Mongolian grasslands and their relationships with climate. Results indicate that climatic variables control approximately 50% of the variation in ecosystem 15N abundance along the transect. Ecosystem 15N abundance decreases as both mean annual precipitation (MAP) and mean annual temperature (MAT) increase. Regional patterns obtained from our study differ from reported global patterns. Ecosystem 15N abundance is negatively correlated with MAT along the eastern part of the transect, while a positive correlation between MAT and ecosystem 15N is apparent at the global scale. MAP exerts stronger controls on ecosystem 15N abundance along the western part of the transect than what is shown in a global regression model. Ecosystem 15N abundance in the western part of the transect is substantially higher (ca. ‰) than the values projected by a global model. The 15Nsoil-plant (‰) (difference in Δ15N values between plant and soil) values in Inner Mongolian grasslands are not significantly correlated with either MAP or MAT; but Δ15Nsoil-plant values are positively correlated with MAT and negatively correlated with MAP at the global scale. These conflicting trends strongly indicate that climatic controls on ecosystem 15N abundance are scale-dependent. Regional N deposition gradients, grazing-induced ammonia volatilization, and variation in plant-soil types are among the possible causes of these inconsistencies. [ABSTRACT FROM AUTHOR]

The protonation and magnetism effects on the spin transport properties of benzo[b]phenazine (BPE) and bis(o‐phenylenediamine) manganese (IV) complex (Mn‐OPD) molecules in series and in parallel are theoretically investigated using density functional theory (DFT) combined with nonequilibrium Green's function method (NEGF). The spin‐resolved current‐voltage curves show that the magnetic field mainly regulate the spin‐polarized direction of current, and the protonation effect will significantly reduce the magnitude of spin‐polarized current. Moreover, under two orthogonal inputs, the molecular combinational circuits can behave as AND and OR spin logic gates, suggesting the application potential of integrating logic operations for future spin‐based nanoelectronics. In addition, we have observed the Fano resonance phenomenon in the parallel molecular junction, and the Fano resonance feature can be canceled by protonation effect. This work proposes a feasible way to construct a complex single‐molecule spin logic gate device. [ABSTRACT FROM AUTHOR]