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Floods can cause masonry buildings to become immersed for a long period of time, which causes the building materials to deteriorate and thus affects the safety performance of the structure. In this study, a long-term-immersed masonry wall was considered as the research object and a cohesive element containing damage evolution was used to simulate the mortar layer, establish a finite-element model of the separated masonry wall and perform numerical loading experiments. Data on crack width variation in the masonry wall was extracted using Python. The effect of a long-termwater-immersion environment on the shear performance of masonry walls was analyzed considering material deterioration. The results show that long-term flooded masonry walls are characterized by low shear capacity and low stiffness and safety reserves cannot be guaranteed. A partially immersed masonry wall is prone to damage from the weak parts and has a high risk coefficient. The macro-damage degree of a masonry wall immersed by a flood is not as serious as that of the original wall in the early stage, but it suddenly increases in the collapse stage and the warning effect of cracks is reduced, which requires special attention in safety assessments. [ABSTRACT FROM AUTHOR]

Knowledge of the evolution of the Bangong-Nujiang Tethyan Ocean is crucial for reconstructing the paleography of the Tethyan Realm, given its significance as a key component of the eastern Tethys. Nonetheless, there has been uncertainty regarding both the timing and the processes involved in the closure of this ocean. This study focused on a 110-106 Ma igneous complex comprising basalts-basaltic andesites, trachyandesites, and granodiorites from the Sumxi area in the western part of the Qiangtang terrane of west-central Tibet. The basalts-basaltic andesites have SiO2 contents of 52.5-58.7 wt% and MgO contents of 2.89-4.63 wt%, and exhibit some arc-like geochemical signatures. However, these rocks also have elevated Nb contents (>10 ppm) and Nb/La ratios (>0.5), as well as enriched Sr-Nd isotopic composition [eNd(Z) = -7.40 to -6.00], implying that they are products of a mantle source metasomatized by adakitic melts. The trachyandesites are characterized by intermediate compositions (SiO2 = 63.6-65.2 wt%), high Mg number (40-60), and more enriched eNd(t) values (-8.37 to -7.49). Comparing their geochemical composition to that of mélange rocks, it is postulated that these trachyandesites were formed through the partial melting of a mantle source including mélange matrix rocks within a subduction zone. The granodiorites exhibit adakitic geochemical features (Sr = 830.14-1032.70 ppm, Y = 14.8615.37 ppm, Sr/Y = 54-68), indicating that they originated from the partial melting of a thickened lower crust in a continental arc setting. Our results, in combination with a synthesis of tectonomagmatism along the Bangong-Nujiang suture zone, provide con-vincing evidence for subduction of an oceanic plateau and subsequent slab roll-back. The Sumxi igneous complex, with its clear arc affinity, suggests that the Bangong-Nujiang Tethyan Ocean, or at least its western part, remained open until the late Early Cretaceous (ca. 106 Ma). [ABSTRACT FROM AUTHOR]

To address the two critical issues of evaluating the necessity of implementing cooling techniques and achieving real-time temperature control of drilling fluids underground in the current drilling fluid cooling technology, we first established a temperature and pressure coupled downhole heat transfer model, which can be used in both water-based and oil-based drilling fluid. Then, fourteen factors, which could affect wellbore temperature, were analyzed. Based on the standard deviation of the downhole temperature corresponding to each influencing factor, the influence of each factor was quantified. The influencing factors that can be used to guide the drilling fluid's cooling technology were drilling fluid thermal conductivity, drilling fluid heat capacity, drilling fluid density, drill strings rotation speed, pump rate, viscosity, ROP, and injection temperature. The nondominated sorting genetic algorithm was used to optimize these six parameters, but the optimization process took 182 min. Combining these eight parameters' influence rules with the nondominated sorting genetic algorithm can reduce the optimization time to 108 s. Theoretically, the downhole temperature has been demonstrated to increase with the inlet temperature increasing linearly under quasi-steady states. Combining this law and PID, the downhole temperature can be controlled, which can reduce the energy for cooling the surface drilling fluid and can ensure the downhole temperature reaches the set value as soon as possible. [ABSTRACT FROM AUTHOR]

Objectives: Recurrent respiratory papillomatosis (RRP) is the most common benign laryngeal tumor in children. It can cause serious psychological and mental burden on patients since RRP requires repeated surgical treatment. This study aims to delineate the global trends and identify hotspots related to RRP over the past two decades. Methods: We systematically gathered research findings on RRP from 2004 to 2023, utilizing the Web of Science as our data source. Subsequently, we performed a comprehensive bibliometric analysis of the literature using Vosviewer, CiteSpace, and Bibliometrics online analysis platform. Results: A total of 839 publications were finally identified on RRP from 2004 to 2023. The United States has the largest number of publications (392), accounting for 46.7%. The Capital Medical University is the most productive organization (24), followed by the Centers for Disease Control and Prevention (18). The most productive journal was the Laryngoscope, with 86 publicatios. Comparatively, Vaccine is the most cited journal (2297). Craig S. Derkay ranked highest among all authors in publication (16). Burst detection shows onset, adjuvant therapy, management, juvenile-onset RRP, systemic bevacizumab, avastin, human papillomavirus vaccine are recent keywords of great interest to researchers. Conclusion: Research on RRP has progressed significantly over the past two decades, especially in terms of therapeutic strategies. We strongly believe that this article will provide new research directions for other researchers and may contribute to future breakthroughs in the field. [ABSTRACT FROM AUTHOR]

Almost all herbivorous insects feed on plants and use sucrose as a feeding stimulant, but the molecular basis of their sucrose reception remains unclear. Helicoverpa armigera as a notorious crop pest worldwide mainly feeds on reproductive organs of many plant species in the larval stage, and its adult draws nectar. In this study, we determined that the sucrose sensory neurons located in the contact chemosensilla on larval maxillary galea were 100-1000 times more sensitive to sucrose than those on adult antennae, tarsi, and proboscis. Using the Xenopus expression system, we discovered that Gr10 highly expressed in the larval sensilla was specifically tuned to sucrose, while Gr6 highly expressed in the adult sensilla responded to fucose, sucrose and fructose. Moreover, using CRISPR/Cas9, we revealed that Gr10 was mainly used by larvae to detect lower sucrose, while Gr6 was primarily used by adults to detect higher sucrose and other saccharides, which results in differences in selectivity and sensitivity between larval and adult sugar sensory neurons. Our results demonstrate the sugar receptors in this moth are evolved to adapt toward the larval and adult foods with different types and amounts of sugar, and fill in a gap in sweet taste of animals. [ABSTRACT FROM AUTHOR]

As one of the most stunning biological nanostructures, the single-diamond (SD) surface discovered in beetles and weevils exoskeletons possesses the widest complete photonic bandgap known to date and is renowned as the "holy grail" of photonic materials. However, the synthesis of SD is difficult due to its thermodynamical instability compared to the energetically favoured bicontinuous double diamond and other easily formed lattices; thus, the artificial fabrication of SD has long been a formidable challenge. Herein, we report a bottom-up approach to fabricate SD titania networks via a one-pot cooperative assembly scenario employing the diblock copolymer poly(ethylene oxide)-block-polystyrene as a soft template and titanium diisopropoxide bis(acetylacetonate) as an inorganic precursor in a mixed solvent, in which the SD scaffold was obtained by kinetically controlled nucleation and growth in the skeletal channels of the diamond minimal surface formed by the polymer matrix. Electron crystallography investigations revealed the formation of tetrahedrally connected SD frameworks with the space group Fd 3 m in a polycrystalline anatase form. A photonic bandgap calculation showed that the resulting SD structure has a wide and complete bandgap. This work solves the complex synthetic enigmas and offers a frontier in hyperbolic surfaces, biorelevant materials, next-generation optical devices, etc. [ABSTRACT FROM AUTHOR]

Poly(ADP-ribose)ylation or PARylation by PAR polymerase 1 (PARP1) and dePARylation by poly(ADP-ribose) glycohydrolase (PARG) are equally important for the dynamic regulation of DNA damage response. PARG, the most active dePARylation enzyme, is recruited to sites of DNA damage via pADPr-dependent and PCNA-dependent mechanisms. Targeting dePARylation is considered an alternative strategy to overcome PARP inhibitor resistance. However, precisely how dePARylation functions in normal unperturbed cells remains elusive. To address this challenge, we conducted multiple CRISPR screens and revealed that dePARylation of S phase pADPr by PARG is essential for cell viability. Loss of dePARylation activity initially induced S-phase-specific pADPr signaling, which resulted from unligated Okazaki fragments and eventually led to uncontrolled pADPr accumulation and PARP1/2-dependent cytotoxicity. Moreover, we demonstrated that proteins involved in Okazaki fragment ligation and/or base excision repair regulate pADPr signaling and cell death induced by PARG inhibition. In addition, we determined that PARG expression is critical for cellular sensitivity to PARG inhibition. Additionally, we revealed that PARG is essential for cell survival by suppressing pADPr. Collectively, our data not only identify an essential role for PARG in normal proliferating cells but also provide a potential biomarker for the further development of PARG inhibitors in cancer therapy. [ABSTRACT FROM AUTHOR]

Steel-concrete composite beam has been increasingly applied to large span cable-stayed bridges. It takes full advantage of the material properties of steel and concrete. However, the concrete deck bears tension in the negative moment zone, such as zero block, which is disadvantageous to structures. Aiming at this problem, a finite element model of the zero block in the negative moment zone of a semi-floating cable-stayed bridge is built, and the local mechanical performance of the bridge deck under completed status is studied. Based on the analysis results, three improvement measures have been proposed. The improvement effect of each method and composed of three methods has been studied. The numerical results show that the whole zero block zone is in the compressed state under the combined action of the bending moment and axial force of the stay cable. However, the local negative moment effect in the zero block zone is very prominent under the support of the diaphragm plate. Removing parts of the diaphragm plate at the bearing position can significantly improve local mechanical behavior in the concrete deck, which transfers the local support to the adjacent two diaphragm plates. The composed improvement effect is prominent when the three measures are adopted simultaneously. [ABSTRACT FROM AUTHOR]

The article introduces SetRank, a novel setwise Bayesian approach for collaborative ranking in recommender systems. It aims to provide sorted item lists to better reflect user preferences. It addresses limitations in existing pairwise and listwise methods, such as the independence assumption and challenges with ties and unobserved data.

This paper reviews the stability, heat transfer efficiency and photothermal conversion efficiency optimization studies of solid-liquid phase change materials (PCM) applied to water heaters. Suggestions and prospects were proposed. The study shows that the solid-liquid PCM are mostly filled in the water tank, thermal storage devices or solar thermal collector heater system with paraffin wax, and the addition of solid-liquid PCM can significantly improve the water heater performance. Further in-depth research is needed on PCM dosage and system economics of their application in heat pump water heaters, and the application of photothermal conversion PCM in solar water heater systems. [ABSTRACT FROM AUTHOR]

This study focuses on the leaf roasting process in the field of tobacco processing. Leaf roasting is an important part of the process to adjust the moisture content of tobacco to the appropriate level, which has a significant impact on the homogenization and processing quality of tobacco. The study focused on the control of key parameters such as temperature, humidity and time in the leaf roasting process and their effects on tobacco quality. The study aimed to provide an in-depth assessment of the impact of the leaf roasting process on the homogenization and processing quality of tobacco. This study provides a scientific basis for optimizing the process parameters and control methods so as to enhance the processing quality of tobacco and the sustainable development of the tobacco industry. In this paper, an evaluation model was constructed to study the effect of leaf beating and re-firing process on tobacco quality by using a combination of BP neural network and genetic algorithm. Tobacco leaf homogenization processing quality indicators, such as moisture, temperature, and chemical composition, were analyzed, and how these factors play a role in the leaf beating and re-roasting process. Meanwhile, principal component analysis and typical correlation analysis were used to identify the main influencing factors, and a comprehensive evaluation model was constructed. The results of the study showed that the key parameters in the leaf beating and roasting process have a significant impact on the quality of tobacco processing. The combined model optimized by BP neural network and genetic algorithm can effectively predict and evaluate the effects of these process parameters on tobacco quality. The evaluation model developed in this study, which is used to analyze and improve the leaf roasting process, helps to improve the processing quality of tobacco leaves and the overall quality of tobacco products. In addition, this study provides a new analytical method and theoretical support for the field of tobacco processing. [ABSTRACT FROM AUTHOR]

The effect of the surface elastic deformation is investigated by the multiscale approach in the hydrodynamic wedge-platform thrust bearing with the ultra low clearance on the 1nm scale, by incorporating both the non-continuum pure adsorbed layer flow and the multiscale "sandwich" film flow. The pure adsorbed layer flow in ultra small surface separations is described by the non-continuum nanoscale flow equation; The "sandwich" film flow is described by the multiscale flow equations respectively for the adsorbed layer flow and the intermediate continuum fluid flow. The numerical calculation results show that in the studied bearing, the effect of the surface elastic deformation is normally significant, it pronouncedly reduces the maximum film pressure, greatly changes both the film pressure profile and the surface separation profile, and considerably increases the minimum surface separation, which occurs on the exit of the bearing. The effect of the surface elastic deformation is shown to be obviously dependent on the fluid-bearing surface interaction. [ABSTRACT FROM AUTHOR]

Rock bursts pose a significant risk to coal mine operation safety. Thus, accurately discriminating coal bursting liabilities is crucial for predicting and preventing rock burst events. To better understand the effects of a varying bedding angle on the crack propagation rule, failure mode and bursting liability level of coal and coal-rock combinations, we propose an optimized machine learning-based model. Additionally, uniaxial compressive tests are conducted using PFC3D software on samples with different bedding angles. The results indicate that, among the nine light gradient boosting machine discriminant models constructed using three data preprocessing methods and three parameter optimization algorithms, the optimal model is identified as the particle swarm optimization-light gradient boosting machine discriminant model based on Z-score standardization method, which exhibits the best stability and has a F1-score of 93.6%. Bedding has a significant impact on the failure modes of two kinds of samples, resulting in an evident bedding effect on their bursting liability. The uniaxial compression strength and bursting energy index of both samples show a reduction-rising trend with an increasing bedding dip angle. However, the bursting liability level of these samples is not affected by 0°C or 90°C bedding dip angle. Therefore, when assessing the bursting liability of samples, the influence of coal seam bedding and its dip angles should be thoroughly considered. [ABSTRACT FROM AUTHOR]

The Indian passive margin has preserved several pulses of magmatism during and after the disassembly of Gondwana since the late Paleozoic, providing valuable insights into the long-term magmatic evolution of various passive margins, including the Indian passive margin. In the Yumai Complex, eastern Tethyan Himalaya, a pulse of Late Triassic alkaline volcanism (ca. 227-216 Ma) is evident. The Late Triassic volcanic rocks are mildly alkaline to tholeiitic basalts with minor ultrabasic rocks, similar in geochemistry to within-plate flood basalts. The TiO2 contents (1.46-3.38 wt%, mainly >2 wt%), (La/Yb)N values (4.05-7.50), εNd(t) values (+4.86 to +6.98), and results from partial-melt modeling suggest that the basalts likely originated from garnet peridotite. Elemental and Sr-Nd systematics of magmatic rocks emplaced during the Triassic indicate oceanic island basalt (OIB) components in the magma source, interpreted as enriched mantle components rather than crustal contamination products. Spatiotemporal and geochemical patterns of magmatism reveal that the bulk compositions of the basalts changed from enriched OIB-like to depleted mid-ocean-ridge basalt (MORB)-like compositions. This phenomenon likely resulted from the evolving nature of the rifting basin, changing from a nascent continental setting to a mature ocean basin. The Triassic magmatism in the Tethyan Himalaya can be attributed to remnant lithospheric instability arising from the prolonged rifting of eastern Gondwana, leading to the formation of a magmatically passive margin. [ABSTRACT FROM AUTHOR]

Liquid crystal elastomers are active materials that combine the anisotropic properties of liquid crystals with the elasticity of polymer networks. The LCEs exhibit remarkable reversible contraction and elongation capabilities in response to external stimuli, rendering them highly promising for diverse applications, such as soft robotics, haptic devices, shape morphing structures, etc. However, the predominant reliance on heating as the driving stimulus for LCEs has limited their practical applications. This drawback can be effectively addressed by incorporating fillers, which can generate heat under various stimuli. The recent progress in LCE composites has significantly expanded the application potential of LCEs. In this minireview, we present the design strategies for soft actuators with LCE composites, followed by a detailed exploration of photothermal and electrothermal LCE composites as prominent examples. Furthermore, we provide an outlook on the challenges and opportunities in the field of LCE composites. [ABSTRACT FROM AUTHOR]

Development of single-component organic phosphor attracts increasing interest due to its wide applications in optoelectronic technologies. Theoretically, activating efficient intersystem crossing (ISC) via 1(p, p*) to 3(p, p*) transitions, rather than 1(n, p*) - 3(p, p*) transitions, is an alternative access to purely organic phosphors but remains challenging. Herein, we designed and successfully synthesized the sila-8-membered ring fused biaryl benzoskeleton by transition metal catalysis, which served as a new organic phosphor with efficient 1(p, p*) to 3(p, p*) ISC. We first found that such a compound exhibits a record-long phosphorescence lifetime of 6.5 s at low temperature for single-component organic systems. Then, we developed two strategies to tune their decay channels to evolve such nonemissive molecules into bright phosphors with elongated lifetimes at room temperature: 1) Physic-based design, where quantitative analyses of electron-phonon coupling led us to reveal and hinder the major nonradiative channels, thus lighted up room temperature phosphorescence (RTP) with a lifetime of 480 ms at 298 K; 2) chemical geometry-driven molecular engineering, where a geometry-based descriptor -TT1-S0/TS0 was developed for rational screening RTP candidates and further improved the RTP lifetime to 794 ms. This study clearly shows the power of interdiscipline among synthetic methodology, physics-based rational design, and computational modeling, which represents a paradigm for the development of an organic emitter. [ABSTRACT FROM AUTHOR]

Accurately identifying the vehicle load on the bridge plays a vital role in structural-stress analysis and safety evaluation. Also, extracting the spatiotemporal information of the vehicle's is crucial for identifying the vehicle load. This study aimed to propose a vehicle spatiotemporal information-identification method based on machine-vision technology. First, digital video surveillance cameras were installed in the front and on the side of the monitoring section to capture real-time videos of vehicles passing through the monitoring section. The background-difference method was used to detect vehicles based on the frontal video. Subsequently, the transverse position was evaluated according to the distance between the vehicle's license plate and the lane line. Other vehicle parameters, including the vehicle's speed, the number of axles and the wheelbase, were identified based on the lateral video and the auxiliary lines with a known distance. Second, a laboratory model experiment and multiple field tests under different scenes were carried out to validate the efficiency and accuracy of the proposed method. The results indicated that the average identification errors of wheelbase for the model experiment and the field tests were all 1.12% and those of the vehicle's speed were 1.25% and 1.35, respectively. Also, the average deviations of the lateral position were 2.57 mm and 2.69 cm, respectively. The variances of the identified error of the three parameters for the field tests were 0.78%, 1.83 cm and 0.54%, respectively. This verified that the proposed method has high accuracy, reliability and good anti-noise performance. [ABSTRACT FROM AUTHOR]

Ureaplasma urealyticum (UU), is one of the most vital pathogens causing genitourinary tract infections of the body, and it can result in poor maternal and perinatal outcomes. The aim of this study was to establish a method to detect Ureaplasma urealyticum based on recombinant polymerase amplification (RPA) technique. Specific primers and probes were designed according to the 16sRNA gene sequence of Ureaplasma urealyticum. Six pathogens were detected for real-time fluorescence RPA specificity verification, including Mycoplasma hominis (MH), Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Staphylococcus aureus, Escherichia coli, and Lactobacillus vaginalis. The sensitivity of the method was performed by gradient dilution of the extracted template. A total of 60 clinical samples were detected by the established real-time fluorescence RPA. Detection of Ureaplasma urealyticum can be completed within 20 minutes at 39 °C using established RPA method. The minimum detection limit of Ureaplasma urealyticum by real-time fluorescence RPA was 3 pg. The evaluation of 60 clinical samples proved that RPA method was feasible. A high specificity, sensitivity, simplicity and rapidity method for Ureaplasma urealyticum detection was successfully established based on the real-time fluorescence RPA method. [ABSTRACT FROM AUTHOR]

Buckling, a phenomenon historically considered undesirable, has recently been harnessed to enable innovative functionalities in materials and structures. While approaches to achieve specific buckling behaviors are widely studied, tuning these behaviors in fabricated structures without altering their geometry remains a major challenge. Here, we introduce an inverse design approach to tune buckling behavior in magnetically active structures through the variation of applied magnetic stimuli. Our proposed magneto-mechanical topology optimization formulation not only generates the geometry and magnetization distribution of these structures but also informs how the external magnetic fields should be applied to control their buckling behaviors. By utilizing the proposed strategy, we discover magnetically active structures showcasing a broad spectrum of tunable buckling mechanisms, including programmable peak forces and buckling displacements, as well as controllable mechano- and magneto-induced bistability. Furthermore, we experimentally demonstrate that multiple unit designs can be assembled into architectures, resulting in tunable multistability and programmable buckling sequences under distinct applied magnetic fields. By employing a hybrid fabrication method, we manufacture and experimentally validate the generated designs and architectures, confirming their ability to exhibit precisely programmed and tunable buckling behaviors. This research contributes to the advancement of multifunctional materials and structures that harness buckling phenomena, unlocking transformative potential for various applications, including robotics, energy harvesting, and deployable and reconfigurable devices. [ABSTRACT FROM AUTHOR]

Antimicrobial susceptibility testing plays a pivotal role in the discovery of new antibiotics. However, the development of simple, sensitive, and rapid assessment approaches remains challenging. Herein, we report an activated alkyne- based cascade signal ampli- fication strategy for ultrafast and high- throughput antibiotic screening. First of all, a novel water- soluble aggregation- induced emission (AIE) luminogen is synthesized, which contains an activated alkyne group to enable fluorescence turn- on and metal- free click bioconjugation under physiological conditions. Taking advantage of the in- house established method for bacterial lysis, a number of clickable biological substances (i.e., bacterial solutes and debris) are released from the bacterial bodies, which remarkably increases the quantity of analytes. By means of the activated alkyne- mediated turn- on click bioconjugation, the system fluorescence signal is significantly amplified due to the increased labeling sites as well as the AIE effect. Such a cascade signal amplification strategy efficiently improves the detection sensitivity and thus enables ultrafast antimicrobial susceptibility assessment. By integration with a microplate reader, this approach is further applied to high- throughput antibiotic screening. [ABSTRACT FROM AUTHOR]

The Mekong River (MR) crosses the borders and connects six countries including China, Myanmar, Laos, Thailand, Cambodia, and Vietnam. It provides critical water resources and supports natural and agricultural ecosystems, socio-economic development, and livelihoods of the people living in this region. Understanding changes in runoff of this important international river under projected climate change is critical for water resource management and climate change adaptation planning. However, research on long-term runoff dynamics for the MR and the underlying drivers of runoff variability remains scarce. Here, we analyse historical runoff variations from 1971 to 2020 based on runoff gauge data collected from eight hydrological stations along the MR.With these runoff data, we then evaluate the runoff simulation performance of four global climate models (GCMs) and five global hydrological models (GHMs) under the ISI-MIP project. Furthermore, based on the best simulation combination, we quantify the impact of future climate change on river runoff changes in the MR. The result shows that the an nual runoff in the MR has not changed significantly in the past five decades, while the establishment of dams and reservoirs in the basin significantly affected the annual runoff distribution.WaterGap2 forced by GCMs ensemble-averaged climates has the best runoff simulation performance. Under representative concentration pathways (RCPs, i.e., RCP2.6, RCP6.0 and RCP8.5), runoff of the MR is projected to increase significantly (from 3.81 m³ s−1 a−1 to 16.36 m³ s−1 a−1). In particular, under the RCP6.0 scenario, the annual runoff increases most significantly in the middle and lower basin due to increased precipitation and snowmelt. Under the RCP8.5 scenario, the runoff distribution in different seasons varies significantly, increasing the risk of flooding in the wet season and drought in the dry season. [ABSTRACT FROM AUTHOR]

Objective: Age-relate cataract (ARC) is a disease of the eyes with no effective drugs to prevent or treat patients. The aim of the present study is to determine whether histone H3, aA-crystallin (CRYAA), ß-galactosidase (GLB1), and p53 are involved in the pathogenesis of ARC. Methods: A total of 99 anterior lens capsules (ALCs) of patients with ARC of various nuclear grades, ultraviolet models of ALCs, and two human lens epithelial cell lines (FHL-124 and SRA01/04) were used, and the expression of histone H3, CRYAA, GLB1, and p53 were detected by immunoblotting and reverse transcription and real time-quantitative polymerase chain reaction. The association between CRYAA with histone H3, GLB1, and p53 was assessed in FHL-124 and SRA01/04 cells following CRYAA overexpression. Results: Histone H3 and p53 in ALCs of patients with ARC were up-regulated in a grade-dependent manner, and the expression of CRYAA showed a positive association with histone H3, p53, and GLB1. In UV models of ALCs and human lens epithelial cell lines, the expression levels of histone H3, cell apoptosis factors (Bax/Bcl-2, cleaved caspase-3), and inflammation factors (interleukin-6, tumor necrosis factor-a) were all up-regulated. Furthermore, transfection of CRYAA in FHL-124 cells induced overexpression of histone H3. Conclusion: CRYAA-mediated upregulation of histone H3 may be involved in the pathogenesis of ARC. p53 may also have a role in ARC development, but not via the CRYAA-histone H3 axis. The results of the present study may assist in improving our understanding of the pathogenesis of ARC and in identifying potential targets for treatment. [ABSTRACT FROM AUTHOR]

Recent years have witnessed the rapid accumulation of massive electronic medical records, which highly support intelligent medical services such as drug recommendation. However, although there are multiple interaction types between drugs, e.g., synergism and antagonism, which can influence the effect of a drug package significantly, prior arts generally neglect the interaction between drugs or consider only a single type of interaction. Moreover, most existing studies generally formulate the problem of package recommendation as getting a personalized scoring function for users, despite the limits of discriminative models to achieve satisfactory performance in practical applications. To this end, in this article, we propose a novel end-toend Drug Package Generation (DPG) framework, which develops a new generative model for drug package recommendation that considers the interaction effects between drugs that are affected by patient conditions. Specifically, we propose to formulate the drug package generation as a sequence generation process. Along this line, we first initialize the drug interaction graph based on medical records and domain knowledge. Then, we design a novel message-passing neural network to capture the drug interaction, as well as a drug package generator based on a recurrent neural network. In detail, a mask layer is utilized to capture the impact of patient condition, and the deep reinforcement learning technique is leveraged to reduce the dependence on the drug order. Finally, extensive experiments on a real-world dataset from a first-rate hospital demonstrate the effectiveness of our DPG framework compared with several competitive baseline methods. [ABSTRACT FROM AUTHOR]

Proteolysis-targeting chimaeras (PROTACs) have been developed to be an emerging technology for targeted protein degradation and attracted the favour of academic institutions, large pharmaceutical enterprises, and biotechnology companies. The mechanism is based on the inhibition of protein function by hijacking a ubiquitin E3 ligase for protein degradation. The heterobifunctional PROTACs contain a ligand for recruiting an E3 ligase, a linker, and another ligand to bind with the protein targeted for degradation. To date, PROTACs targeting ~70 proteins, many of which are clinically validated drug targets, have been successfully developed with several in clinical trials for diseases therapy. In this review, the recent advances in PROTACs against clinically validated drug targets are summarised and the chemical structure, cellular and in vivo activity, pharmacokinetics, and pharmacodynamics of these PROTACs are highlighted. In addition, the potential advantages, challenges, and prospects of PROTACs technology in disease treatment are discussed. [ABSTRACT FROM AUTHOR]

BRDs proteins that recognise chromatin acetylation regulate gene expression, are epigenetic readers and master transcription coactivators. BRDs proteins are now emerging as targets for new therapeutic development. Blocking the function of any of BRDs proteins can be a control agent for diseases, such as cancer. Traditional drugs like enzyme inhibitors and protein-protein inhibitors have many limitations. The therapeutic efficacy of them remains to be proven. Recently, Proteolysis-Targeting Chimaeras (PROTACs) have become an advanced tool in therapeutic intervention as they remove disease-causing proteins. Extremely potent and efficacious small-molecule PROTACs of the BRDs proteins, based on available, potent, and selective BRDs inhibitors, have been reported. This review presents a comprehensive overview of the development of PROTACs for BRDs proteins regulation in cancer, and the chances and challenges associated with this area are also highlighted. [ABSTRACT FROM AUTHOR]

Proteolytic targeting chimaeras (PROTACs) have been developed as an effective technology for targeted protein degradation. PROTACs are heterobifunctional molecules that can trigger the polyubiquitination of proteins of interest (POIs) by recruiting the ubiquitin-proteasome system, thereby inhibiting the intracellular level of POIs. To date, a variety of small-molecule PROTACs (CRBN, VHL, IAP, and MDM2-based PROTACs) have been developed. IAP-based PROTACs, also known as specific and nongenetic IAP-dependent protein erasers (SNIPERs), are used to degrade the target proteins closely related to diseases. Their structures consist of three parts, including target protein ligand, E3 ligase ligand, and the linker between them. So far, many SNIPERs have been extensively studied worldwide and have performed well in multiple diseases, especially cancer. In this review, we will present the most relevant advances in the field of SNIPERs and provide our perspective on the opportunities and challenges for SNIPERs to become therapeutic agents. [ABSTRACT FROM AUTHOR]

Chemical drug design based on the biochemical characteristics of cancer cells has become an important strategy for discovering new anti-tumour drugs to improve tumour targeting effects and reduce off-target toxicities. Colchicine is one of the most prominent and historically microtubule-targeting drugs, but its clinical applications are hindered by notorious adverse effects. In this study, we presented a novel tumour-specific conjugate 9 that consists of deacetylcolchicine (Deac), biotin, and a cleavable disulphide linker. 9 was found to exhibit potent anti-tumour activity and exerted higher selectivity between tumour and nontarget cells than Deac. The targeting moiety biotin might enhance the transport capability and selectivity of 9 to tumour cells via biotin receptor-mediated endocytosis. The tubulin polymerisation activity of 9 (with DTT) was close to the parent drug Deac. These preliminary results suggested that 9 is a high potency and reduced toxicity antitumor agent and worthy of further investigation. [ABSTRACT FROM AUTHOR]

A set of novel diarylpyridines as anti-tubulin agents were designed, synthesised using a rigid pyridine as a linker to fix the cis-orientation of ring-A and ring-B. All of the target compounds were evaluated for their in vitro antiproliferative activities. Among them, 10t showed remarkable antiproliferative activities against three cancer cell lines (HeLa, MCF-7 and SGC-7901) in submicromolar concentrations. Consistent with its potent anti-proliferative activity, 10t also displayed potent anti-tubulin activity. Cellular mechanism investigation elucidated 10t disrupted the cellular microtubule structure, arrested cell cycle at G2/M phase and induces apoptosis. Molecular modelling studies showed that 10t could bind to the colchicine binding site on microtubules. These results provide motivation and further guidance for the development of new CA-4 analogues. [ABSTRACT FROM AUTHOR]

With the advancements in information and communication technologies, our world is now a global village. Efficient and novel technologies are now available for the effective transmission of different kinds of data, along with future challenges for making these transmissions more and more effective. Various joint training procedures have been developed to improve the performance delay and throughput of communication systems. These architectures can make the communication persistent in different scenarios and enhance the capacity of a channel. A study was conducted to show the advantages of various joint training procedures for the overcoming of different transmission defects. With the implementation of these procedures, different issues in transmission like power and resource allocation, channel capacity, adaptability, and many more can be resolved very efficiently. After the thorough revision of the existing literature, the present study has identified some of the most valuable features from it. From these features, the most prominent ones are selected and their weights are computed with the use of the Analytical Hierarchy Process (AHP). To help people choose the best training methods, the MCDM procedure called TOPSIS was used to rank the available options with the help of the weights from AHP. [ABSTRACT FROM AUTHOR]

As a major component of strategic talent management, learning and development (L&D) aims at improving the individual and organization performances through planning tailored training for employees to increase and improve their skills and knowledge. While many companies have developed the learning management systems (LMSs) for facilitating the online training of employees, a long-standing important issue is how to achieve personalized training recommendations with the consideration of their needs for future career development. To this end, in this article, we present a focused study on the explainable personalized online course recommender system for enhancing employee training and development. Specifically, we first propose a novel end-to-end hierarchical framework, namely Demand-aware Collaborative Bayesian Variational Network (DCBVN), to jointly model both the employees’ current competencies and their career development preferences in an explainable way. In DCBVN, we first extract the latent interpretable representations of the employees’ competencies from their skill profiles with autoencoding variational inference based topic modeling. Then, we develop an effective demand recognition mechanism for learning the personal demands of career development for employees. In particular, all the above processes are integrated into a unified Bayesian inference view for obtaining both accurate and explainable recommendations. Furthermore, for handling the employees with sparse or missing skill profiles, we develop an improved version of DCBVN, called the Demand-aware Collaborative Competency Attentive Network (DCCAN) framework, by considering the connectivity among employees. In DCCAN, we first build two employee competency graphs from learning and working aspects. Then, we design a graph-attentive network and a multi-head integration mechanism to infer one’s competency information from her neighborhood employees. Finally, we can generate explainable recommendation results based on the competency representations. Extensive experimental results on realworld data clearly demonstrate the effectiveness and the interpretability of both of our frameworks, as well as their robustness on sparse and cold-start scenarios. [ABSTRACT FROM AUTHOR]

The Triassic tectonic setting of the Tethyan Himalaya in southern Tibet remains controversial and is key to revealing the mechanism of Neo-Tethys Ocean opening and the breakup history of Gondwana. This paper reports 227-225 Ma mafic volcanic rocks interbedded within the Tethyan Himalaya sequence in southern Tibet, which were formed in a typical passive continental margin setting. The basalts are tholeiitic with high TiO2 (3.20-3.38 wt%) and moderate MgO (4.05-5.40 wt%) contents and exhibit enrichment in light rare earth elements and weak negative Nb, Ta, Eu, and Ti anomalies. These geochemical compositions, combined with uniform whole-rock eNd(t) (+1.50 to +2.70) values, indicate that the magmas were derived by low-degree melting of a deep-seated garnet source that was heterogeneously modified by an oceanic island basalt-type of component. Given the other geological evidence, we propose that the magmatic evolution of the Tethyan Himalaya during the late Paleozoic-Mesozoic was generally a lithospheric thinning process, that is, it evolved from a fully developed continental rift system during the Late Permian to wane during the Triassic. This interpretation further supports the hypothesis that the Neo-Tethys Ocean opened in a passive pattern and that the breakup of Gondwana in the late Paleozoic was initiated by lithospheric thinning. Therefore, the subsequent magmatism was related to the passive upwelling of normal asthenospheric materials. [ABSTRACT FROM AUTHOR]

To investigate the direct evidence for a number of physico-chemical processes related to pluton construction and growth, we examine the Buya pluton of West Kunlun in Northwestern China, which emplaced within the 455-460 Ma time frame. Field observations, geochemical data, and thermodynamic modeling show that mafic dikes of the Buya pluton were conduits for magma chamber replenishment during pluton construction. These mafic inputs, and the enclaves that resulted from them, induced compaction of the semi-consolidated, crystal-rich, felsic mushes below them. The accumulation of highly silicic, fine-grained granite at the top of the Buya pluton is the result of episodic melt segregation events from these mushes. This sequence of events may reflect a common process that promotes compositional variation in granite suites. Combined geochemical and Hf- and Nd-isotopic data suggest that parental magmas of the mafic sheet and enclave are similar to sanukitoid, which is potentially consistent with a mantle peridotitic source metasomatized by slab melts. These mafic magmas intruded the lower crust where the original magma was modified by mafic lower-crust melt. Following emplacement at shallow crustal levels of the mafic inputs (~3.7 kbar, ~5.3 km, constrained by amphibole geobarometry), the felsic mush evolved through the extraction of interstitial melts driven by hybridization with episodic inputs of mafic magmas as well as crystal consequent accumulation and fractional crystallization of plagioclase, hornblende, and accessory phases such as allanite, apatite, and zircon. This fractional crystallization process may also provide an explanation for the apparently high Sr/Y features in some silicic high-K, calc-alkaline magmas. [ABSTRACT FROM AUTHOR]

A new isoflavan glucoside, namely astramemside A (1), together with six known compounds (2-7) were obtained from the roots of a traditional Chinese medicine, Astragalus membranaceus var. mongholicus. Their structures were elucidated by spectroscopic analyses (HRESIMS, UV, IR, 1D and 2D NMR), and the absolute configuration of 1 was determined by combination of chemical transformation and single-crystal X-ray diffraction. Compound 1 showed moderate inhibition on nitric oxide (NO) production induced by lipopolysaccharide in RAW264.7 cells with an IC50 value of 38.98 + 5.28 ?M. [ABSTRACT FROM AUTHOR]

Glycerol-3-phosphate dehydrogenase (GPDH) catalyses the interconversion of glycerol-3-phosphate (G3P) and dihydroxyacetone phosphate (DHAP), and plays key roles in different developmental processes and stress responses. GPDH family genes have been previously investigated in various plant species, such as Arabidopsis, maize, and soybean. However, very little is known in GPDH family genes in wheat. In this study, a total of 17 TaGPDH genes were identified from the wheat genome, including eight cytosolic GPDHs, six chloroplastic GPDHs and three mitochondrial GPDHs. Gene duplication analysis showed that segmental duplications contributed to the expansion of this gene family. Phylogenetic results showed that TaGPDHs were clustered into three groups with the same subcellular localization and domain distribution, and similar conserved motif arrangement and gene structure. Expression analysis based on the RNA-seq data showed that GPDH genes exhibited preferential expression in different tissues, and several genes displayed altered expression under various abiotic stresses. These findings provide the foundation for further research of wheat GPDH genes in plant growth, development and stress responses. [ABSTRACT FROM AUTHOR]

This article provides an analyses the implications of China’s constitutionally proclaimed notion of “Community of Shared Future for Mankind” (CSFM), which reveals the stance of the PRC party in promoting so-called “Chinese wisdom” and a “Chinese solution” to address common issues in global governance and in pursuing China’s global leadership in President Xi Jinping’s “New Era.” The author explores the possibility for China and the West of reaching a normative consensus in terms of standards set by the CSFM vision and human security in light of the current global pandemic. The author advocates pursuing a pragmatic, problem-solving approach to international engagement with China without advancing a particular political agenda based on broad ideological presumptions, namely by encouraging and facilitating China’s further participation in international institutions and treaties. This approach may establish an increasing convergence and resonance of local and nonlocal norms to reach a normative consensus and, ultimately, to influence treaty performance incrementally and gradually. [ABSTRACT FROM AUTHOR]

China plans to establish a lunar orbital VLBI (Very Long Baseline Interferometer) station around 2025, which will carry a space passive hydrogen maser as the time and frequency reference. Since it is the first time to use a space passive hydrogen maser for VLBI observation, its feasibility needs to be studied and verified. Therefore, we carried out VLBI observations using the space passive hydrogen maser as the frequency reference. In the experiment, the active hydrogen atomic clock and space passive hydrogen maser were used as the frequency standard, and the alternate VLBI observations of China's Mars probe TW1 (Tianwen 1) were carried out using the 25 m radio telescope at Sheshan, Shanghai, and other VLBI stations. The results of data processing and analysis show that the standard deviation of VLBI residual group delay based on both active hydrogen atomic clock and space passive hydrogen maser are within 0.5 ns, which indicates that the space passive hydrogen maser can meet the accuracy requirements of VLBI measurement for deep space exploration, and verify its feasibility as the frequency standard of lunar orbital VLBI stations. [ABSTRACT FROM AUTHOR]

New taxonomic and nomenclatural data are provided for Chinese species of Sarcophaga Meigen, 1824. Eight new synonyms are proposed: two at the genus level, Magnicauda Wei, 2005 syn. nov. = Sarcophaga Meigen, 1824 and Leigongshanophaga Lehrer & Wei, 2010 syn. nov. = Sarcophaga Meigen, 1824, two at the subgenus level, Magnicauda Wei, 2005 syn. nov. = Pterosarcophaga Ye, 1981 and Leigongshanophaga Lehrer & Wei, 2010 syn. nov. = Cornexcisia Fan & Kano, 2000, and four at the species level, Sarcophaga catoptosa Wei & Yang, 2007 syn. nov. = Sarcophaga suthep Pape & Bänziger, 2003, Pierretia daozhenensis Wei, 2005 syn. nov. = Sarcophaga sichotealini (Rohdendorf, 1938), Pierretia autochthona Wei & Yang, 2007 syn. nov. = Sarcophaga (Liosarcophaga) kanoi Park, 1962, and Parasarcophaga simultaneousa Wei & Yang, 2007 syn. nov. = Sarcophaga huangshanensis (Fan, 1964). Sarcophaga (Liosarcophaga) aegyptica Salem, 1935 is considered a senior synonym of Sarcophaga (Liosarcophaga) parkeri (Rohdendorf, 1937). Correct original spellings are established, by First Reviser action, for the genus-group names Magnicauda Wei, 2005 and Pterosarcophaga Ye, 1981 and for the species-group name Magnicauda linjiangensis Wei, 2005. Chinese material of Sarcophaga (Bellieriomima) genuforceps, S. (Robineauella) huangshanensis (holotype and paratype), S. (Liosarcophaga) kanoi, and S. (L.) aegyptica is photographed for the first time. [ABSTRACT FROM AUTHOR]

Cell surface proteins play essential roles in various biological processes and are highly related to cancer development. They also serve as important markers for cell identity and targets for pharmacological intervention. Despite their great potentials in biomedical research, comprehensive functional analysis of cell surface proteins remains scarce. Here, with a de novo designed library targeting cell surface proteins, we performed in vivo CRISPR screens to evaluate the effects of cell surface proteins on tumor survival and proliferation. We found that Kirrel1 loss markedly promoted tumor growth in vivo. Moreover, KIRREL was significantly enriched in a separate CRISPR screen based on a specific Hippo pathway reporter. Further studies revealed that KIRREL binds directly to SAV1 to activate the Hippo tumor suppressor pathway. Together, our integrated screens reveal a cell surface tumor suppressor involved in the Hippo pathway and highlight the potential of these approaches in biomedical research. [ABSTRACT FROM AUTHOR]

We describe a simple aptamer assay for the rapid analysis of aflatoxin B1 (AFB1), a potently carcinogenic fungal metabolite. The original anti-AFB1 aptamer was rationally truncated, obtaining a short aptamer that displayed better performance. Different concentrations of AFB1 were detected by measuring the circular dichroism spectra of this short aptamer. The detection limit reached 0.6 nM, which was lower than that of the original aptamer (80 nM). [ABSTRACT FROM AUTHOR]

It is of great significance to design a sustainable extractive distillation separation configuration that can implement efficient separation of the ternary multi-azeotropic mixtures with a large single component content and propose a feasible and accuracy sustainable evaluation method. This is because the extractive distillation separation scheme with preconcentration should be designed for the particularity of such ternary multi-azeotropic azeotropes. To fill this gap, the paper designs a novel and sustainable three-column extractive distillation process containing one integrated distillation column (TCED-IDC) with both preconcentration and solvent recovery functions and two extractive distillation columns taking the separation of the tetrahydrofuran/ethanol/water ternary multi-azeotropic mixtures containing large amounts of water as an example. Simultaneously, economic optimization of the TCED-IDC process as well as the conventional three-column extractive distillation (TCED) process and the four-column extractive distillation (FCED) process is implemented to determine economically optimal design parameters via minimizing the total annual costs (TAC) using genetic algorithm. Following that, environmental and thermodynamic evaluations are comprehensively conducted to prove the advantages of the TCED-IDC process. The TCED-IDC separation schemes achieves 79.05%/8.47% reduction in CO2 emissions and 71.92%/9.57% economic cost savings compared to the TCED and the FCED schemes, and the corresponding thermodynamic efficiency is 7.87%. Moreover, an extended Eco-efficiency Comparison Index (ECI) method is proposed to perform the eco-efficiency analysis covering economic, environmental, and thermodynamic aspects for the three extractive distillation separation processes proposed. The analysis results demonstrate that the integration of preconcentration and solvent recovery functions improve the eco-efficiency compared to the other two separation schemes, and the corresponding ECI reaches 91.57% and achieves 1.42% points increase compared to the FCED scheme. [ABSTRACT FROM AUTHOR]

This paper introduces the power function lognormal (PFL) distribution, which assumes a power function distribution up to a specified threshold, and a lognormal distribution beyond it. It can be positively or negatively skewed, and/or leptokurtic/platykurtic. Maximum likelihood, moment, nonlinear least squares, and Bayes estimators are obtained. A simulation study is performed, numerical computations are carried out to display the performance of the proposed method, and insurance claims data are analyzed for illustrative purposes. [ABSTRACT FROM AUTHOR]

Oncogenic imbalance of DNA methylation is well recognized in cancer development. The ten-eleven translocation (TET) family of dioxygenases, which facilitates DNA demethylation, is frequently dysregulated in cancers. How such dysregulation contributes to tumorigenesis remains poorly understood, especially in solid tumors which present infrequent mutational incidence of TET genes. Here, we identify loss-of-function mutations of TET in 7.4% of human lung adenocarcinoma (LUAD), which frequently co-occur with oncogenic KRAS mutations, and this co-occurrence is predictive of poor survival in LUAD patients. Using an autochthonous mouse model of KrasG12D-driven LUAD, we show that individual or combinational loss of Tet genes markedly promotes tumor development. In this Kras-mutant and Tet-deficient model, the premalignant lung epithelium undergoes neoplastic reprogramming of DNA methylation and transcription, with a particular impact on Wnt signaling. Among the Wnt-associated components that undergo reprogramming, multiple canonical Wnt antagonizing genes present impaired expression arising from elevated DNA methylation, triggering aberrant activation of Wnt signaling. These impairments can be largely reversed upon the restoration of TET activity. Correspondingly, genetic depletion of β-catenin, the transcriptional effector of Wnt signaling, substantially reverts the malignant progression of Tet-deficient LUAD. These findings reveal TET enzymes as critical epigenetic barriers against lung tumorigenesis and highlight the therapeutic vulnerability of TET-mutant lung cancer through targeting Wnt signaling. [ABSTRACT FROM AUTHOR]

In this paper, we first prove the global well-posedness of a scaled anisotropic MHD system in a two-dimensional striped domain with small initial data in Sobolev space, under the assumption the initial tangential magnetic field is not zero. Then, we justify the limit from the anisotropic MHD system to the hydrostatic MHD system and get the precise convergence rate in L∞. [ABSTRACT FROM AUTHOR]

Translation speed is an important factor determining locally accumulated disasters induced by tropical cyclones (TCs). We found that the basin wide TC translation speed over the western North Pacific (WNP) in the late season (October-December) experienced an abrupt decrease in the early 1980s. However, this slowdown cannot be explained by the previously proposed deceleration in large-scale steering. In this study, we demonstrated that this slowdown results from the decreased proportion of subtropical TC track frequency in the early 1980s. Because late-season large-scale steering flow in the subtropical WNP is much greater than that in the tropical WNP, TCs influencing the subtropical WNP generally hold greater translation speed than that of TCs staying in the tropical WNP. Thus, a decrease in the ratio of subtropical TC track frequency can lead to a notable decrease in the basin wide TC translation speed. The decreased ratio of subtropical TC track frequency results from the strengthened southwestward steering and the reduced ratio of TC genesis in the tropical eastern WNP, which is linked to a WNP anticyclonic circulation that appears to be driven by the Atlantic Multi-decadal Oscillation. The result introduces the crucial role of TC track shift in the basin wide TC translation speed and has important implications for understanding the effects of climate change on TC translation speed. [ABSTRACT FROM AUTHOR]

Objectives Curcumin presents some therapeutic effects including anti-cancer and anti-inflammation. Herein, we centred on the functional role of curcumin in cerebral ischaemia injury and its potential molecular mechanisms. Methods Microarray analysis was used for excavating crucial genes in cerebral ischaemia. PC12 cells were subjected to oxygen-glucose deprivation and reoxygenation (OGD/R) to imitate cerebral ischaemia/reperfusion (I/R) injury in vitro. Cell viability and apoptosis abilities were evaluated by Cell Counting Kit-8 and flow cytometry assays. qRT-PCR, Western blot and enzyme-linked immunosorbent assays were performed to assess the concentrations of related genes. Key findings By enquiring GEO dataset, C-C motif chemokine ligand 3 (CCL3) was profoundly upregulated in cerebral I/R injury model. And CCL3 was found to be highly expressed in PC12 cells suffered from OGD/R. Moreover, we found that CCL3 was a potential target of curcumin in cerebral I/R injury. More importantly, the following experiments illustrated that curcumin inhibited the expression of CCL3 in OGD/R model and reduced cell apoptosis and inflammation. Moreover, high expression levels of TLR4, MyD88, p-NF-κB P65, p-P38 MAPK and p-IκBα in OGD/R model were inhibited by curcumin. Conclusions Our study manifested that curcumin might be a meritorious drug for the treatment of cerebral ischaemia by acting on CCL3. [ABSTRACT FROM AUTHOR]

Graphene confinement provides a new physical and mechanical environment with ultrahigh van der Waals pressure, resulting in new quasi-two-dimensional phases of few-layer ice. Polymorphic transition can occur in bilayer constrained water/ice system. Here, we perform a comprehensive study of the phase transition of AA-stacked bilayer water constrained within a graphene nanocapillary. The compression-limit and superheating-limit (phase) diagrams are obtained, based on the extensive molecular-dynamics simulations at numerous thermodynamic states. Liquid-to-solid, solid-to-solid, and solid-to-liquid-to-solid phase transitions are observed in the compression and superheating of bilayer water. Interestingly, there is a temperature threshold (∼275 K) in the compression-limit diagram, which indicates that the first-order and continuous-like phase transitions of bilayer water depend on the temperature. Two obviously different physical processes, compression and superheating, display similar structural evolution; that is, square ice-nanotube arrays (BL-VHDI) will bend first and then transform into bilayer triangular AA stacking ice (BL-AAI). The superheating limit of BL-VHDI exhibits local maxima, while that of BL-AAI increases monotonically. More importantly, from a mechanics point of view, we propose a novel mechanism of the transformation from BL-VHDI to BL-AAI, both for the compression and superheating limits. This structural transformation can be regarded as the "buckling failure" of the square-ice-nanotube columns, which is dominated by the lateral pressure. [ABSTRACT FROM AUTHOR]

Density-functional theory plus the Hubbard U correction (DFT + U) method is widely used in first-principles studies of strongly correlated systems, as it can give qualitatively (and sometimes, semi-quantitatively) correct description of energetic and structural properties of many strongly correlated systems with similar computational cost as local density approximation or generalized gradient approximation. On the other hand, the DFT + U approach is limited both theoretically and practically in several important aspects. In particular, the results of DFT + U often depend on the choice of local orbitals (the local projection) defining the subspace in which the Hubbard U correction is applied. In this work we have systematically investigated the issue of the local projection by considering typical transition metal oxides, β-MnO2 and MnO, and comparing the results obtained from different implementations of DFT + U. We found that the choice of the local projection has significant effects on the DFT + U results, which are more significant for systems with stronger covalent bonding (e.g., MnO2) than those with more ionic bonding (e.g., MnO). These findings can help to clarify some confusion arising from the practical use of DFT + U and may also provide insights for the development of new first-principles approaches beyond DFT + U. [ABSTRACT FROM AUTHOR]