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We use the particle flow code PFC3D to simulate the triaxial compression of sandstone under various radial stresses and loading strain rates to determine the triaxial stress-strain curves, crack propagation path, and contact forces to investigate the failure process of sandstone. We analyze the energy and damage evolution during triaxial compression. The results indicate that the tension and shear-induced cracks increase with the increase of radial stress under the same loading strain rate. Both normal and tangential contact forces exhibit strong anisotropy and increase with radial stress and strain rate. The normal contact force has an approximately symmetrical distribution with respect to the horizontal plane, whereas the tangential contact force has an approximately symmetrical distribution with respect to the axis. For the characteristics of the energy evolution, the boundary energy density, strain energy density, and dissipated energy density all increase linearly with the radial stress, and the boundary energy density increases at the fastest rate, followed by the strain energy density and dissipated energy density. In the post-peak stage the primary energy consumption is the dissipated energy. After that, in the remaining stage the strain energy decreases gradually. By analyzing the evolution of the damage variables in the prepeak area we observed that the damage variable followed an exponential relationship with the axial strain. When the loading strain rate is constant, the damage variable corresponding to the same strain value decreases with increase of radial stress. The results indicate that the increase in radial stress delays the damage acceleration. In contrast, the effect of the loading strain rate on the damage variable is small. The findings reveal the internal structural evolution of rocks during deformation and failure. [ABSTRACT FROM AUTHOR]

Single-molecule recognition and detection with the highest resolution measurement has been one of the ultimate goals in science and engineering. Break junction techniques, originally developed to measure single-molecule conductance, recently have also been proven to have the capacity for the label-free exploration of single-molecule physics and chemistry, which paves a new way for single-molecule detection with high temporal resolution. In this review, we outline the primary advances and potential of the STM break junction technique for qualitative identification and quantitative detection at a single-molecule level. The principles of operation of these single-molecule electrical sensing mainly in three regimes, ion, environmental pH and genetic material detection, are summarized. It clearly proves that the single-molecule electrical measurements with break junction techniques show a promising perspective for designing a simple, label-free and nondestructive electrical sensor with ultrahigh sensitivity and excellent selectivity. [ABSTRACT FROM AUTHOR]

Autophagy, a cellular self-digestion process, involves the degradation of targeted cell components such as damaged organelles, unfolded proteins, and intracellular pathogens by lysosomes. It is a major quality control system of the cell and plays an important role in cell differentiation, survival, development, and homeostasis. Alterations in the cell autophagic machinery have been implicated in several disease conditions, including neurodegeneration, autoimmunity, cancer, infection, inflammatory diseases, and aging. In non-alcoholic fatty liver disease, including its inflammatory form, non-alcoholic steatohepatitis (NASH), a decrease in cell autophagic activity, has been implicated in the initial development and progression of steatosis to NASH and hepatocellular carcinoma (HCC). We present an overview of autophagy as it occurs in mammalian cells with an insight into the emerging understanding of the role of autophagy in NASH and NASH-related HCC. [ABSTRACT FROM AUTHOR]

Solar-driven hydrogen production from water has attracted increasing attention due to sustainable H2 fuel generation with zero-emissions. However, the design of a photocatalyst without noble metals to enable efficient water splitting is still critical for practical applications. In this study, the hierarchical microspheres of SrWO4 assembled with well-defined metallic Bi nanoparticles were synthesized through mild hydrothermal aging. The resultant photocatalyst with optimum proportion exhibited the competitive performance of a high hydrogen-generation rate at 4.5 mmol·h−1·g−1, outperforming SrWO4 and Bi by factors of 2.0 and 2.4, respectively. Both the experimental characterization and active analysis revealed that the synergistic effect of noble metal-like behavior of Bi and their electron-sink capacity mainly contribute to boosting the overall photocatalytic efficiency. This work may provide advanced insights into the application of economical bismuth elements as co-catalysts, instead of noble metals, to improve photocatalytic efficiency in solar-fuel conversion and environmental remediation. [ABSTRACT FROM AUTHOR]

The Weishan REE deposit is located in the southwest of the Luxi Terrane of the North China Craton (NCC), where a large number of lamprophyre dikes are spatially exposed with the deposit. Here, we report petrology, geochemistry and zircon U-Pb geochronology data for the lamprophyre of the Weishan REE deposit in order to develop constraints for the determination of the petrogenesis, magma source and evolution of the lamprophyre and the tectonic environment. LA-LCP-MS zircon U-Pb dating shows that the crystallization age of the lamprophyre is 125 ± 0.86 Ma. The geochemical data suggest that these lamprophyres have high levels of Al2O3, K2O, MgO and alkalis, moderate level of Na2O and low levels of SiO2, Fe2O3 and TiO2, and that they are enriched with LREEs (La, Ce) and LILEs (Rb, Ba) and depleted with regard to HREEs and HFSEs (Nb, Ta, Ti). They displayed negative εHf(t) values of −14.98 to −9.03, TDM1 ages of 1.1–1.4 Ga and TDM2 ages of 1.7–2.1 Ga, which suggest that the magma source originates from an enriched mantle. Low Rb/Sr and high Dy/Yb ratios suggest that the enriched mantle source was partially melted at the amphibole-bearing lherzolite garnet-facies. The high Ba/Th and Sr/Th ratios indicate that the enriched source was derived from subduction dehydration fluids of the oceanic crust. We propose that the mafic dike intrusions are consistent with an Early Cretaceous alkaline magma emplacement in an extensional setting, in which the magma was not contaminated by crustal material during its emplacement. [ABSTRACT FROM AUTHOR]

The Luxi Terrane (eastern China) exposes widespread Early Cretaceous alkaline rocks, whereas their petrogenesis remains controversial, including fractional crystallization, partial melting and crustal contamination regime. Here, we present petrology, geochemistry, sphene U-Pb geochronology and trace element data from the syenogranite, quartz syenite and quartz monzonite of the Guandimiao alkaline complex rocks to investigate their petrogenesis. Geochemical data suggest that these alkaline rocks show alkalic and peralkaline characters, and high Ga/Al ratios, SiO2, light rare-earth element (LREE), Zr and Nb, and low MgO, CaO, Eu contents, corresponding to A-type granites. Sphene trace elements in syenogranite and quartz monzonite show obvious fractionation between LREE and heavy rare-earth element (HREE) and high Th/U ratios, indicating a magmatic origin. They yield U-Pb lower intercept ages of 128 ± 2.3 Ma and 127 ± 1.3 Ma, representing the crystallization ages of these alkaline rocks. The negative correlations between CaO, Fe2O3 (Total), MgO, P2O5, TiO2, MnO and the pronounced depletion in Nb, Ta and Ti suggest that the alkaline rocks were formed by fractional crystallization. Additionally, the positive correlation between La/Hf and La, Th and Th/V, Ce/Yb and K2O, and Tb/Yb and Yb suggest that the alkaline melts are generated by partial melting. Such high Rb/Nb, (Th/Nb)N and Nb/Th ratios indicate crustal contamination during the magma emplacement. We, therefore, propose the magma source of the alkaline rocks in the Guandimiao complex originated by partial melting of lithospheric mantle, which experienced fractional crystallization and crustal contamination processes during its emplacement. Such complex alkaline rocks were probably formed in an extensional back-arc setting induced by the retreat of the subducting Izanagi plate. [ABSTRACT FROM AUTHOR]

It is of great importance to investigate spring wheat yield affected by the climate at different latitudes in the Rice-Wheat Rotation System. Two spring wheat varieties used as the study objects were planted at two locations of different latitudes in 2017–2018 and 2018–2019. Six sowing dates were selected for planting the wheat seeds. The quantity of basic seedlings for the first sowing date was 300 × 104 ha−1, which was increased by 10% on each date in the following sowing proceeding. Results showed that as the latitude increased, the mean daily temperature and effective accumulated temperature decreased, the mean solar radiation and accumulated solar radiation increased; as the effective accumulated temperature decreased, the yield decreased by 0.18 t ha−1 on average; and dry matter accumulation decreased by 0.6 t ha−1 on average. As the sowing date was delayed, the mean daily temperature and mean daily solar radiation increased, and the effective accumulated temperature and accumulated solar radiation decreased. Due to the decrease in the accumulated solar radiation and increase in mean daily temperature, the yield decreased by 0.27 t ha−1 on average and the dry matter decreased by 0.39 t ha−1 on average by postponing one sowing date. The effective accumulated temperature and accumulated solar radiation were significantly positively correlated with wheat yield and dry matter accumulation, and the mean daily temperature was significantly negatively correlated with wheat yield and dry matter accumulation. The temperature productivity at a high latitude was higher than lower latitude. The radiation productivity at a high latitude was lower than lower latitude. The productivity of the temperature and radiation first increased and then decreased when the sowing time was delayed. [ABSTRACT FROM AUTHOR]

Inequalities play important roles not only in mathematics but also in other fields, such as economics and engineering. Even though many results are published as Hermite–Hadamard (H-H)-type inequalities, new researchers to these fields often find it difficult to understand them. Thus, some important discoverers, such as the formulations of H-H-type inequalities of α -type real-valued convex functions, along with various classes of convexity through differentiable mappings and for fractional integrals, are presented. Some well-known examples from the previous literature are used as illustrations. In the many above-mentioned inequalities, the symmetrical behavior arises spontaneously. [ABSTRACT FROM AUTHOR]

Increasingly serious microplastic pollution in coastal areas and the ecological threats associated with plastics have attracted global attention. The frequency and intensity of typhoons have increased owing to global warming, strongly influencing the distribution and composition of microplastics in coastal ecosystems. In this study, the abundance, composition, diversity, and flux of microplastics in three estuaries and one sewage outlet in Zhanjiang Bay (ZJB) were analyzed. The average abundance of microplastics from land-based sources increased 3.6-fold from 14.19 ± 3.60 items/L before Typhoon Kompasu to 51.19 ± 28.53 items/L after the typhoon (p < 0.05). In addition, the proportion of fiber and large microplastics increased after the typhoon. In all samples, microplastics 100–330 μm in size were predominant, and blue was the most abundant color. The diversity in the color and size of microplastics increased after Typhoon Kompasu. The total daily flux of microplastics at the four stations entering ZJB was 3.95 × 1011 items before the typhoon and 9.93 × 1011 items after the typhoon, showing a 2.5-fold increase. This study demonstrated the influence of Typhoon Kompasu on microplastics from land-based sources of ZJB coastal waters and provided vital data for further study on MP pollution in coastal water ecosystems and the impact of typhoons on microplastics. [ABSTRACT FROM AUTHOR]

Pyrazolo[3,4-b]pyridines are a group of heterocyclic compounds presenting two possible tautomeric forms: the 1H- and 2H-isomers. More than 300,000 1H-pyrazolo[3,4-b]pyridines have been described which are included in more than 5500 references (2400 patents) up to date. This review will cover the analysis of the diversity of the substituents present at positions N1, C3, C4, C5, and C6, the synthetic methods used for their synthesis, starting from both a preformed pyrazole or pyridine, and the biomedical applications of such compounds. [ABSTRACT FROM AUTHOR]

Modular building is becoming a common sight due to government policies promoting greater automation and productivity. When moving towards modularity, indoor comfort within volumetric modules, such as levels of humidity and temperature, natural ventilation, and air pollutant transport, have a major effect on human health and well-being. Computational fluid dynamics simulations (CFD) are used to evaluate the efficiency of natural ventilation. However, designers usually find it difficult to visualize the CFD simulation results, which can deepen users' understanding of the wind environment and help optimize the design of modular buildings. To overcome this challenge, this paper presents an integrated approach based on building information modeling (BIM) and virtual reality (VR), with the aim of analyzing the aerodynamic design and wind comfort for modular buildings. The framework consists of four salient components. First, a new method, combining OpenStreetMap and Dynamo, is proposed to achieve rapid urban modeling of modular buildings. The second step involves the use of CFD to simulate the outdoor wind environment surrounding modular buildings. The third step emphasizes the integration of CFD-computed data with VR applications to create an immersive virtual environment for designers to analyze the wind environment of design alternates. Finally, the visual experience of non-professional users is used to improve the ventilation of the building and support more informed decision marking at the early stage of building design. The proposed framework is illustrated via a case study that focuses on a group of modular housings in the urban area of Singapore. The results indicate that visualization of CFD simulations in VR provides designers with more details regarding the actual space, and it is expected to help optimize the architectural design. [ABSTRACT FROM AUTHOR]

Convex functions are studied very frequently by means of the Hadamard inequality. A symmetric function leads to the generalization of the Hadamard inequality; the Fejér–Hadamard inequality is one of the generalizations of the Hadamard inequality that holds for convex functions defined on a finite interval along with functions which have symmetry about the midpoint of that finite interval. Lately, integral inequalities for convex functions have been extensively generalized by fractional integral operators. In this paper, inequalities of Hadamard type are generalized by using exponentially (α , h-m)-p-convex functions and an operator containing an extended generalized Mittag-Leffler function. The obtained results are also connected with several well-known Hadamard-type inequalities. [ABSTRACT FROM AUTHOR]

Fractional integral operators are useful tools for generalizing classical integral inequalities. Convex functions play very important role in the theory of mathematical inequalities. This paper aims to investigate the Hadamard type inequalities for a generalized class of functions namely strongly (α , h − m) -p-convex functions by using Riemann–Liouville fractional integrals. The results established in this paper give refinements of various well-known inequalities which have been published in the recent past. [ABSTRACT FROM AUTHOR]

Apatite is a nearly ubiquitous accessory phase in igneous rocks that crystallizes during the entire magma evolution process and has great implications for geochronology and petrogenesis. Previous studies suggested that Nb-Ta mineralization in the giant Renli deposit was genetically related to Late Jurassic two-mica monzogranite or Early Cretaceous muscovite monzogranite. Moreover, the magmatic–hydrothermal evolution of these two stages is poorly understood. In our study, we confirm that the muscovite monzogranite, biotite monzogranite, and two-mica monzogranite are all spatially associated with Nb-Ta pegmatites. We present new apatite U-Pb ages to constrain the timing of Nb-Ta mineralization and related magmatism. The results show that apatite from the two-mica pegmatite yield a lower intercept age of 130 ± 2 Ma (2σ), and apatite grains from two two-mica pegmatite samples yield a lower intercept age of 135 ± 8 Ma (2σ) and 134 ± 3 Ma (2σ), respectively. Apatite and whole-rock geochemistry suggest the oxidation degree of the Nb-Ta mineralization increases from north (RL-6) to south (RL-16) in the giant Renli deposit. This study demonstrates that a combination of apatite composition and U-Pb ages can be used to constrain the magmatic–hydrothermal evolution of granite and pegmatite-type Nb-Ta deposits. [ABSTRACT FROM AUTHOR]

A copolymer of styrene and maleic anhydride was modified via reaction with 4-amino-5-methyl-4H-1,2,4-triazole-3-thiol, and palladium(II) chloride was then immobilized on the modified copolymer. The resulting nanocatalyst was characterized by scanning electron microscopy (SEM), energy dispersive spec-troscopy, X-ray (EDAX) and inductively coupled plasma (ICP) analyses, and FT-IR, 1H NMR, and 13C NMR spectroscopic data. The catalytic efficiency of the new palladium nanoparticles was successfully examined in the Suzuki cross-coupling reaction of various aryl halides with phenylboronic acid in water. The advantages of this strategy were easy recovery and efficient reusability of the expensive PdNPs, high yields of the cross-coupling products, short reaction times, and the use of water as a solvent for a wide range of substrates. [ABSTRACT FROM AUTHOR]

Layered periodic foundations (LPFs) with identical unit cells have been proposed as a type of seismic metamaterials due to the unique dynamic characteristic of attenuation zones. However, it is difficult to design attenuation zones with both comparatively low starting frequencies and large bandwidths for traditional LPFs with identical unit cells. In this paper, combined layered periodic foundations (CLPFs) are proposed by combining two traditional LPFs with different unit cells in tandem. Combined attenuation zones of the CLPFs are identified by investigating the frequency response functions of the CLPFs. The generation mechanism of the combined attenuation zones was studied by varying the configuration of CLPFs. The results show that the combined attenuation zones are the union of attenuation zones of the two traditional LPFs. To verify the efficiency of CLPFs, the seismic responses of a four-story frame structure with CLPF are simulated. The present work is very helpful for the design of CLPFs with attenuation zones with a low starting frequency and large bandwidth. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibet Plateau has a vast area of approximately 70×104 km2 of alpine meadow under the impacts of soil freezing and thawing, thereby inducing intensive water erosion. Quantifying the rainfall erosion process of partially thawed soil provides the basis for model simulation of soil erosion on cold‐region hillslopes. In this study, we conducted a laboratory experiment on rainfall‐induced erosion of partially thawed soil slope under four slope gradients (5, 10, 15, and 20°), three rainfall intensities (30, 60, and 90 mm h−1), and three thawed soil depths (1, 2, and 10 cm). The results indicated that shallow thawed soil depth aggravated soil erosion of partially thawed soil slopes under low hydrodynamic conditions (rainfall intensity of 30 mm h−1 and slope gradient ≤ 15°), whereas it inhibited erosion under high hydrodynamic conditions (rainfall intensity ≥ 60 mm h−1 or slope gradient > 15°). Soil erosion was controlled by the thawed soil depth and runoff hydrodynamic conditions. When the sediment supply was sufficient, the shallow thawed soil depth had a higher erosion potential and a larger sediment concentration. On the contrary, when the sediment supply was insufficient, the shallow thawed soil depth resulted in lower sediment erosion and a smaller sediment concentration. The hydrodynamic runoff conditions determined whether the sediment supply was sufficient. We propose a model to predict sediment delivery under different slope gradients, rainfall intensities, and thawed soil depths. The model, with a Nash–Sutcliffe efficiency of 0.95, accurately predicted the sediment delivery under different conditions, which was helpful for quantification of the complex feedback of sediment delivery to the factors influencing rainfall erosion of partially thawed soil. This study provides valuable insights into the rainfall erosion mechanism of partially thawed soil slopes in the Qinghai–Tibet Plateau and provides a basis for further studies on soil erosion under different hydrodynamic conditions. [ABSTRACT FROM AUTHOR]

Induction of phytoalexin production after invading pathogens is recognized as an essential aspect of the plant‐induced resistance. The WRKY family includes plant‐specific transcriptional factors associated with plant defense responses, but the comprehensive mechanisms are poorly understood. Here, we attempted to elaborate the regulatory function of VvWRKY18 from the group IIa of WRKY transcription factor (TF) from Vitis vinifera, in the regulation of β‐aminobutyric acid (BABA)‐activated stilbene phytoalexins biosynthesis and PATHOGENESIS‐RELATED (PR) genes expressions in grapes. BABA at 10 mmol L−1 triggered a priming protection in grapes and conferred a potentiation of the expression levels of VvWRKY18, VvNPR1, and several salicylic acid (SA)‐responsive genes, which was accompanied by enhanced stilbene production upon Botrytis cinerea infection. In addition, a physical interaction between VvWRKY18 and the regulatory protein VvNPR1 was detected in vivo and in vitro by yeast‐2‐hybrid (Y2H), pull‐down and co‐immunoprecipitation assay (Co‐IP) assays. Furthermore, yeast‐1‐hybrid (Y1H) and dual‐luciferase reporter (DLR) assays indicated that VvWRKY18 activated the transcription of STILBENE SYNTHASE (STS) genes, including VvSTS1 and VvSTS2, by directly binding the W‐box elements within the specific promoters and resultantly enhancing stilbene phytoalexins biosynthesis. Further investigation demonstrated that heterologous expression of VvWRKY18 elevated the transcriptions of STS and PR genes, thus contributing to potentiating the defense of transgenic Arabidopsis thaliana plants and resultantly inhibiting B. cinerea invasion. Hence, VvWRKY18 serves as a singular effector involved in the synthesis of stilbene phytoalexins in grapes and its interaction with VvNPR1 provided DNA binding ability required for VvNPR1 to initiate systemic acquired resistance (SAR) defense. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the non-convex interval-valued functions for fuzzy-interval-valued functions, which are called -convex fuzzy-interval-valued functions, by means of fuzzy order relation. This fuzzy order relation is defined level-wise through Kulisch–Miranker order relation given on the interval space. By using the -convexity concept, we present fuzzy-interval Hermite–Hadamard inequalities for fuzzy-interval-valued functions. Several exceptional cases are debated, which can be viewed as useful applications. Interesting examples that verify the applicability of the theory developed in this study are presented. The results of this paper can be considered as extensions of previously established results. [ABSTRACT FROM AUTHOR]

Summary: High salinity, one of the most widespread abiotic stresses, inhibits photosynthesis, reduces vegetation growth, blocks respiration and disrupts metabolism in plants. In order to survive their long‐term lifecycle, trees, such as Populus species, recruit the abscisic acid (ABA) signaling pathway to adapt to a saline environment. However, the molecular mechanism behind the ABA‐mediated salt stress response in woody plants remains elusive. We have isolated a WRKY transcription factor gene, PalWRKY77, from Populus alba var. pyramidalis (poplar), the expression of which is repressed by salt stress. PalWRKY77 decreases salt tolerance in poplar. Furthermore, PalWRKY77 negatively regulated ABA‐responsive genes and relieved ABA‐mediated growth inhibition, indicating that PalWRKY77 is a repressor of the ABA response. In vivo and in vitro assays revealed that PalWRKY77 targets the ABA‐ and salt‐induced PalNAC002 and PalRD26 genes by binding to the W‐boxes in their promoters. In addition, overexpression of both PalNAC002 and PalRD26 could elevate salt tolerance in transgenic poplars. These findings reveal a novel negative regulation mechanism for the ABA signaling pathway mediated by PalWRKY77 that results in more sensitivity to salt stress in poplar. This deepens our understanding of the complex responses of woody species to salt stress. Significance Statement: This work reveals a novel negative regulation mechanism for the abscisic acid (ABA) signaling pathway mediated by PalWRKY77 that results in more sensitivity to salt stress in poplar. This deepens our understanding of the complex responses of woody species to salt stress and of the relationship between ABA signaling and salt stress responses. [ABSTRACT FROM AUTHOR]

High-concentration Al deoxidation resulting in diversified aggregated patterns of alumina inclusions in high-Al iron melt were observed, especially, a new alumina agglomerate with a ring shape was reported and discussed in the current work. A large number of small alumina particle originated from the explosive nucleation of alumina in Fe-Al-O reaction zone with high-concentration Al in a short time is the critical condition for forming the alumina-agglomerated ring. To understand the stabilities of the ring, the relationships among the liquid capillary force, the equivalent inner radius of ring, the filling angle, and the separation distance h were quantitatively investigated based on a mathematical model and experimental results. The new phenomenon and formation mechanism of alumina-agglomerated ring could be important to high-Al steel metallurgy. [ABSTRACT FROM AUTHOR]

The nozzle-clogging problem is closely related to the agglomeration behavior of inclusions in steel-containing rare earth (RE). The present study first optimized the thermodynamic model by supplementing thermodynamic data of the RE compound to study the formation of various inclusions in the Ce-Al-O-S system. Based on that, laboratory-scale experiments with different Ce and Al contents were designed to obtain samples containing a single type of inclusions, viz., Al2O3, Ce-Al-O, Ce2O3, and Ce-O-S, respectively. Additionally, the agglomeration behavior of inclusions was observed in situ by confocal laser scanning microscopy (CLSM), and the calculated attractive forces were used to compare the agglomeration tendency of the four inclusions. The results show that the agglomeration of Al2O3 inclusions is attributed to the strongest attractive force (1.0 × 10−15N to 3.0 × 10−14N) among the four kinds of inclusions. Although Ce-Al-O and Ce2O3 inclusions have the weaker attractive forces (1.3 × 10−16N to 2.0 × 10−14N), they can also agglomerate together and form large-sized clusters. The attractive forces between Ce-O-S inclusions are the weakest (2.1 × 10−18N to 6.0 × 10−16N), that is, this kind of inclusion is more difficult to agglomerate than other inclusions. The study can provide theoretical support for improving the nozzle-clogging problem of RE-containing steel from the inclusion-controlling perspective. [ABSTRACT FROM AUTHOR]

A multi-machine study has been carried out to investigate the impact of a strongly bounded wave propagation domain on the Lower Hybrid current drive, a condition which occurs principally in high aspect ratio tokamaks. In this regime, the condition of kinetic resonance can be far above the upper boundary of the propagation domain, and may not be achieved by the usual toroidal upshift. Therefore no tail of fast electrons can be pulled out from the thermal bulk. Nevertheless, while tokamak plasmas are in principle almost transparent to the wave in this regime so-called "unbridgeable spectral gap", full current drive is well achieved for the two tokamaks considered in this study, TRIAM-1M (Zushi et al. Nucl Fusion 43:1600, 2003) and WEST (Bourdelle et al. Nucl Fusion 55:063017, 2015), both characterized by a very large aspect ratio R / a > 5.5 . The case of the high aspect ratio tokamak HL-2A (Liu et al. Nucl Fusion 45:S239, 2005) for which the wave propagation domain has also an upper boundary, but close to the resonance condition, is considered by comparison. First principles modeling of the rf-driven current and the fast electron bremsstrahlung using the ALOHA/C3PO/LUKE/R5-X2 chain of codes shows unambiguously that the spectral gap must be already filled at the separatrix in order to reproduce quantitatively observations and some important parametric dependencies. This result is an important milestone in the physics understanding of the Lower Hybrid current drive, highlighting the existence of a powerful and likely universal alternative mechanism to bridge the spectral gap, that is not related to toroidal magnetic refraction. With an initially broad power spectrum, lobes with low parallel refractive indexes that carry most of the plasma current can be absorbed in almost single pass, restoring the full validity of the ray-tracing approximation for describing the propagation of the Lower Hybrid wave in cold plasmas. [ABSTRACT FROM AUTHOR]

Poly(styrene-co-maleic anhydride) (SMA) was reacted with 4-amino-6-methyl-3-thioxo-1,2,4-triazine-5-one to obtain the corresponding imide [SMI] which was used as a substrate for immobilization of PdCl2 and preparation of palladium nanoparticles (PdNPs). The supported PdNPs were fully characterized using scanning electron microscopy (SEM), energy dispersive X-ray (EDAX) and FTIR spectroscopy, and inductively coupled plasma spectrometry (ICP). The catalytic efficiency of the PdNPs was evaluated examined successfully in one the established and useful reaction so-called the Suzuki cross-coupling reaction involving the reaction of various aryl halides with phenylboronic acid in water. The advantages of this procedure include easy recovery and efficient reusability of the expensive PdNPs, high yields of the cross coupled products, short reaction times, and use of water as a green solvent for a wide range of substrates. [ABSTRACT FROM AUTHOR]

Summary: Bacterial pathogen Dickeya zeae strain EC1 produces antibiotics‐like phytotoxins called zeamines, which are major virulence determinants encoded by the zms gene cluster. In this study, we identified a zeamine‐deficient mutant with a Tn5 insertion in a gene designated as vfmI encoding a two‐component system (TCS) sensor histidine kinase (HK), which is accompanied by vfmH encoding a response regulator (RR) at the same genetic locus. Domain analysis shows this TCS is analogous to the VfmIH of D. dadantii, with typical characteristics of sensor HK and RR, respectively, and sharing the same operon. Deletion of either vfmI or vfmH resulted in decreased production of zeamines and cell wall degrading enzymes (CWDEs), and alleviated virulence on rice seeds and potato tubers. In D. dadantii 3937, VfmH was shown to bind to the promoters of vfmA and vfmE, while in D. zeae EC1, VfmH could bind to the promoters of vfmA, vfmE and vfmF. RNA‐seq analysis of strain EC1 and its vfmH mutant also showed that the TCS positively regulated a range of virulence genes, including zms, T1SS, T2SS, T3SS, T6SS, flagellar and CWDE genes. [ABSTRACT FROM AUTHOR]

Periodic foundations for seismic isolation are getting increasing attention in the field of civil engineering. Initial stresses due to the vertical loads from the upper structures exist in periodic foundations. In the present paper, attenuation zones of two-dimensional periodic foundations including the effect of vertical loads are studied by the weak form quadrature element method. Comparisons with existing results in special cases without the effect of vertical loads are conducted to validate the proposed method, and good agreement is found. A comprehensive parametric study is conducted to investigate the effects of vertical loads on the attenuation zones. Moreover, frequency-domain and time-domain response analyses of a two-dimensional periodic foundation with finite unit cells are conducted to verify the theoretical results. The results show that bound frequencies of the attenuation zones, corresponding to the vibration mode of the core, are affected by vertical loads. It is also found that vertical loads shift the complete attenuation zones to lower frequencies and reduce the attenuation coefficients in the attenuation zones. [ABSTRACT FROM AUTHOR]

γ-aminobutyric acid (GABA) and Isinglass a collagen peptide have been utilized as highly efficient bifunctional biocatalysts for the efficient and convenient synthesis of 2-aminobenzothiazolomethyl-2-naphthols through a one-pot three-component Mannich reaction between diverse aldehydes, 2-naphthol and 2-aminobenzothiazole under solvent-free condition in high yields. Moreover, GABA could be recycled and reused at least four times without noticeable loss of its activity. [ABSTRACT FROM AUTHOR]

Featured Application: The method of reverberation-ray matrix (MRRM) and the interpretation of bending waves proposed in this paper provide respectively analysis method and profound knowledge for bending waves in bi-coupled periodic multi-component beams. These achievements will push forward the applications of bi-coupled periodic multi-component beams in wave filtering and vibration isolation. Most existing research on periodic beams concerns bending waves in mono-coupled and bi-coupled periodic mono-component beams with the unit cell containing only one beam segment, and very few works on bi-coupled periodic multi-component beams with the unit cell containing more than one beam segments study the bending waves in structures with only binary unit cells. This paper presents the method of reverberation-ray matrix (MRRM) as an alternative theoretical method for analyzing the dispersion characteristics of bending waves with the wavelength greater than the size of the cross-sections of all components in bi-coupled periodic multi-component beams. The formulation of MRRM is proposed in detail with its numerically well-conditioned property being emphasized, which is validated through comparison of the results obtained with the counterpart results by other methods for exemplified bi-coupled periodic beams. Numerical examples are also provided to illustrate the comprehensive dispersion curves represented as the relations between any two among three in frequency, wavenumber (wavelength) and phase-velocity for summarizing the general features of the dispersion characteristics of bending waves in bi-coupled periodic multi-component beams. The effects of the geometrical and material parameters of constituent beams and the unit-cell configuration on the band structures are also demonstrated by numerical examples. The most innovative finding indicated from the dispersion curves is that the frequencies corresponding to the Brillouin zone boundary may not be the demarcation between the pass-band and stop-band for bending waves in bi-coupled periodic multi-component beams. [ABSTRACT FROM AUTHOR]

A concise and efficient one-pot synthesis of 3-functionalized 4-hydroxycoumarin derivatives via a three-component domino reaction of 4-hydroxycoumarin, phenylglyoxal and 3-arylaminocyclopent-2-enone or 4-arylaminofuran-2(5H)-one under catalyst-free and microwave irradiation conditions is described. This synthesis involves a group-assisted purification process, which avoids traditional recrystallization and chromatographic purification methods. Keywords: 3-functionalized 4-hydroxycoumarin; multi-component domino reaction; catalyst-free; group-assisted purification process derivatives via a three-component domino reaction of 4-hydroxycoumarin, phenylglyoxal and 3- arylaminocyclopent-2-enone or 4-arylaminofuran-2(5H)-one under catalyst-free and microwave irradiation conditions is described. This synthesis involves a group-assisted purification process, which avoids traditional recrystallization and chromatographic purification methods. [ABSTRACT FROM AUTHOR]

Cell wall hemicelluloses and pectins are O-acetylated at specific positions, but the significance of these substitutions is poorly understood. Using a transgenic approach, we investigated how reducing the extent of O-acetylation in xylan affects cell wall chemistry, plant performance and the recalcitrance of lignocellulose to saccharification. The Aspergillus niger acetyl xylan esterase AnAXE1 was expressed in Arabidopsis under the control of either the constitutively expressed 35S CAMV promoter or a woody-tissue-specific GT43B aspen promoter, and the protein was targeted to the apoplast by its native signal peptide, resulting in elevated acetyl esterase activity in soluble and wall-bound protein extracts and reduced xylan acetylation. No significant alterations in cell wall composition were observed in the transgenic lines, but their xylans were more easily digested by a β-1,4-endoxylanase, and more readily extracted by hot water, acids or alkali. Enzymatic saccharification of lignocellulose after hot water and alkali pretreatments produced up to 20% more reducing sugars in several lines. Fermentation by Trametes versicolor of tissue hydrolysates from the line with a 30% reduction in acetyl content yielded ∼70% more ethanol compared with wild type. Plants expressing 35S:AnAXE1 and pGT43B:AnAXE1 developed normally and showed increased resistance to the biotrophic pathogen Hyaloperonospora arabidopsidis, probably due to constitutive activation of defence pathways. However, unintended changes in xyloglucan and pectin acetylation were only observed in 35S:AnAXE1- expressing plants. This study demonstrates that postsynthetic xylan deacetylation in woody tissues is a promising strategy for optimizing lignocellulosic biomass for biofuel production. [ABSTRACT FROM AUTHOR]

The morphodynamics of a river flood on a fan delta and its resultant stratigraphic and sedimentary signatures have been studied by means of a flume experiment under controlled boundary conditions. The experiment revealed that deposition was dominant in flood periods when the channels were highly loaded with sediments. In contrast, erosion was dominant in periods of low flow. Mouth bars were formed when a subaqueous channel began to backfill. The development of a mouth bar began with progradation in the down-dip direction and proceeded by aggradation, then retrogradation and finally transverse growth. A channel bifurcated in multiple stages by sequentially forming mouth bars or by simultaneously forming arrays of mouth bars. During the bifurcation, the diffluent point moved upstream, which resulted in channel migration and the development of a delta lobe. Flood events triggered fan-delta front slide-slump deposits. [ABSTRACT FROM AUTHOR]

Nitrogen-fixing rhizobia colonize legume roots via plant-made intracellular infection threads. Genetics has identified some genes involved but has not provided sufficient detail to understand requirements for infection thread development. Therefore, we transcriptionally profiled Medicago truncatula root hairs prior to and during the initial stages of infection. This revealed changes in the responses to plant hormones, most notably auxin, strigolactone, gibberellic acid, and brassinosteroids. Several auxin responsive genes, including the ortholog of Arabidopsis thaliana Auxin Response Factor 16 , were induced at infection sites and in nodule primordia, and mutation of ARF16a reduced rhizobial infection. Associated with the induction of auxin signaling genes, there was increased expression of cell cycle genes including an A-type cyclin and a subunit of the anaphase promoting complex. There was also induction of several chalcone O -methyltransferases involved in the synthesis of an inducer of Sinorhizobium meliloti nod genes, as well as a gene associated with Nod factor degradation, suggesting both positive and negative feedback loops that control Nod factor levels during rhizobial infection. We conclude that the onset of infection is associated with reactivation of the cell cycle as well as increased expression of genes required for hormone and flavonoid biosynthesis and that the regulation of auxin signaling is necessary for initiation of rhizobial infection threads. [ABSTRACT FROM AUTHOR]

An improved synthesis of multifunctionalized pyrrolo[2,3,4-kl]acridine derivatives with different substituted patterns using silica sulfuric acid (SSA) as a heterogeneous catalyst under microwave irradiation conditions was developed. The reaction could be conducted by using readily available and inexpensive substrates within short periods of 12-15 min. under microwave irradiation. Compared with the conventional methods, the remarkable advantages of this method are milder reaction conditions, operational simplicity, higher yields, short reaction times, and an environmentally friendly procedure. [ABSTRACT FROM AUTHOR]

This conference report summarizes the contributions to and discussions at the 2nd Asia-Pacific Transport Working Group Meeting held in Chengdu, China, from 15 to 18 May 2012. The topics of the meeting were organized under five main headings: momentum transport, non-locality in transport, edge turbulence and L-H transition, three-dimensional effects on transport physics, and particle, momentum and heat pinches. It is found that lower hybridwave and ion cyclotronwave induce co-current rotation while electron cyclotronwave induces counter-current rotation. A four-stage imaging for low (L) to high (H) confinement transition gradually emerges and a more detailed verification is urgently expected. The new edge-localized modes mitigation technique with supersonic molecular beam injection was approved to be effective to some extent on HL-2A and KSTAR. It is also found that low collisionality, trapped electron mode to ion temperature gradient transition (or transition of higher to lower density and temperature gradients), fuelling and lithium coating are in favour of inward pinch of particles in tokamak plasmas. [ABSTRACT FROM AUTHOR]

A series of 4-aryl-6-methyl-3,4-dihydro-2H-pyrano[3,2-c]quinolin-2,5(6H)-diones were synthesized via the three-component reactions of aromatic aldehydes, 4-hydroxy-1- methylquinolin-2(1H)-one, and Meldrum's acid catalyzed by L-proline. The structures of the products were identified by spectroscopic analysis. A mechanism for this three-component reaction catalyzed by L-proline was proposed. [ABSTRACT FROM AUTHOR]

Suzuki-Miyaura coupling reactions are promoted by Pd complexes ligated with C2-symmetric multi-dentate N-heterocyclic carbenes derived in situ from Pd(OAc)2 and imidazolium salts. Good to excellent yields were obtained for aryl bromides as substrates. Turnover numbers of up to 105 could be achieved with 5 x 10-4 mol% of Pd(OAc)2/1 x 10-3 mol% NHC precatalyst in 24 h. [ABSTRACT FROM AUTHOR]

Autophagy is a housekeeping survival mechanism with a protective function against stress conditions. However, when stress severity or duration increases, it may promote cell death. Paradoxically, autophagy favors cancer development, since cancer cells could enhance their proliferation potential (thus becoming able to resist anticancer therapy) thanks to the energetic supply provided by organelle degradation typically driven by autophagy following a stepwise pathway. The main actors of the autophagic machinery as well as the features shared with apoptosis will be described. Special attention will be paid to the effects of autophagy manipulation. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes (AOPs), defined as those technologies that utilize the hydroxyl radical (·OH) for oxidation, have received increasing attention in the research and development of wastewater treatment technologies in the last decades. These processes have been applied successfully for the removal or degradation of toxic pollutants or used as pretreatment to convert recalcitrant pollutants into biodegradable compounds that can then be treated by conventional biological methods. The efficacy of AOPs depends on the generation of reactive free radicals, the most important of which is the hydroxyl radical (·OH). The authors summarize the formation reactions of ·OH and the mechanisms of pollutants degradation. They cover six types of advanced oxidation processes, including radiation, photolysis and photocatalysis, sonolysis, electrochemical oxidation technologies, Fenton-based reactions, and ozone-based processes. Controversial issues in pollutants degradation mechanism were discussed. They review the application of these processes for removal of different kinds of toxic pollutants from wastewater, including aromatic compounds, dyes, pharmaceutical compounds, and pesticides, with emphasis on the parameters assessed, removal effectiveness, and the degradation mechanisms of pollutants. The authors discuss issues associated with practical wastewater treatment and offer suggestions for the direction for future researches. [ABSTRACT FROM PUBLISHER]

passively mode-locked dual-wavelength Nd: GdVO laser with orthogonal polarizations is experimentally demonstrated. By changing the absorbed pump power, the laser can mode lock either at 1063 nm (with π polarization) or 1065 nm (with σ polarization), or simultaneously at both wavelengths with orthogonal polarizations. When mode locked at 1063 nm and 1065 nm, the laser produced pulses of 10 ps and 5.9 ps, respectively, with repetition rates of 143.7 MHz and 143.9 MHz. When simultaneously mode locked at both wavelengths, the pulsewidth was about 7 ps. The laser was demonstrated by exploiting the thermal lens and birefringence of the Nd: GdVO crystal. The laser uses one cavity and does not require the insertion of additional optical components. [ABSTRACT FROM AUTHOR]