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The aim of this paper is to establish the existence of solutions for singular double-phase problems depending on one parameter. This work improves and complements the existing ones in the literature. There seems to be no results on the existence of solutions for singular double-phase problems.

In this paper, we consider a nonlocal p(x)-Kirchhoff problem with a p+-superlinear subcritical Caratheodory reaction term, which does not satisfy the Ambrosetti–Rabinowitz condition. Under some certain assumptions, we prove the existence of nontrivial solutions and many solutions. Our results are an improvement and generalization of the corresponding results obtained by Hamdani et al. (2020).

Oxidative stress is unavoidable for aerobic organisms. When abiotic and biotic stresses are encountered, oxidative damage could occur in cells. To avoid this damage, defense mechanisms must be timely and efficiently modulated. While the response to oxidative stress has been extensively studied in plants, little is known about how the activated response is switched off when oxidative stress is diminished. By studying Arabidopsis mutant paraquat tolerance3, we identified the genetic locus PARAQUAT TOLERANCE3 (PQT3) as a major negative regulator of oxidative stress tolerance. PQT3, encoding an E3 ubiquitin ligase, is rapidly down-regulated by oxidative stress. PQT3 has E3 ubiquitin ligase activity in ubiquitination assay. Subsequently, we identified PRMT4b as a PQT3-interacting protein. By histone methylation, PRMT4b upregulates the expression of APX1 and GPX1, encoding two key enzymes against oxidative stress. On the other hand, PRMT4b is recognized by PQT3 for targeted degradation via 26S proteasome. Therefore, we have identified PQT3 as an E3 ligase that acts as a negative regulator of activated response to oxidative stress and found that histone modification by PRMT4b at APX1 and GPX1 loci plays an important role in oxidative stress tolerance.

A series of Ni based catalysts with different supports and basic additives were prepared by sequential impregnation method. The catalysts were characterized by XRD, BET, H2-TPR and CO2-TPD techniques. It was found that the introduction of basic additives enhanced the basicities of catalyats and promoted the dispersities of Ni particles by strong interaction between Ni2+ and basic additives. Among the Ni based catalysts, 10%Ni/10%La2O3/ZrO3 showed the superior performance in sorbitol hydrogenolysis. The synergistic effect of Ni and La2O3 was proven to play an essential role in selective synthesis of EG and 1,2-PG. In the optimal reaction condition, the catalyst presented 100% sorbitol conversion and over 48% glycols (EG and 1,2-PG) yield. The kinetics study of polyols (sorbitol, xylitol and glycerol) hydrogenolysis showed that polyols with more hydroxyl number have higher activity and products distribution was final results of kinetic balance, which could give us some inspiration about how to change the products selectivity. [ABSTRACT FROM AUTHOR]

We report the petrology, whole-rock geochemistry, zircon LA-ICP-MS U-Pb chronology and zircon Hf isotopic data of Daxigou granitoids (western part of the Kuluketage Block, NW China) to evaluate their likely petrogenesis and tectonic setting. Zircons from syenogranite can be divided into two groups: 1) those that display oscillatory zoning and high Th/U ratios (average =1.38), implying their magmatic origin and 2) those that exhibit weak zoning and extremely high U and Pb contents but low Th/U ratios (average = 0.35), resembling zircons that experienced hydrothermal alteration. The zircon LA-ICP-MS U-Pb dating of the two groups of zircons yielded weighted mean ages of 1830 ±12 Ma (MSWD = 0.78) and 1798 ± 21 Ma (MSWD = 1.6) respectively. The Daxigou granitoids belong mostly to normal-K and sodium-rich metaluminous calc-alkaline type, systematically enriched in LREE and large ion lithophile elements (LILE, e.g., K, Ba and Rb), but significantly depleted in high field strength elements (HFSE, e.g., Ti, P, Nb, Ta and U). Their εHf(t) values and two-stage Hf model ages range from -7.16 to -5.03 and 2.69 to 2.76 Ga, respectively. Taken together, it is suggested that Daxigou granitoids are of I-type affinity and that they were derived by partial melting of a Neoarchaean TTG (e.g., Tuoge Complex) rocks in a continental-arc environment. These new data, combined with previous regional geological studies, demonstrate that a series of Palaeoproterozoic (c. 2.0-1.8 Ga) tectono-magmatic events occurred in Kuluketage Block during the assembly of Columbia. [ABSTRACT FROM AUTHOR]

Monodisperse erythrocyte-like Cd2Ge2O6superstructures have been successfully prepared viaa facile and fast microwave-assisted solution-phase approach, employing Cd(Ac)2·2H2O and GeO2as the reactants in the presence of hydrazine monohydrate. The phase and morphology of the product were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), energy dispersive spectrometry (EDS), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM). Such monoclinic phase Cd2Ge2O6microstructures were found to be constructed by abundant single crystalline nanoneedles. Some influencing factors such as the reaction time, reaction temperature, the volume of hydrazine monohydrate and the cadmium source were revealed to play crucial roles in the formation of the Cd2Ge2O6architecture. A possible growth mechanism was proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

We report here the preparation of self-assembled persimmon-like (BiO)2CO3microstructures viaa simple hydrothermal process. Powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM), selected area electron diffraction (SAED) and high resolution transmission electron microscopy (HRTEM) were employed to characterize the phases and morphologies of the products. The reactants could greatly influence the phases and morphologies of the final products. The growth process of the persimmon-like (BiO)2CO3microstructures has been investigated. The persimmon-like (BiO)2CO3could be utilized as a sacrificial template to synthesize sphere-like Bi2S3microstructures by a chemical transformation process. The as-prepared (BiO)2CO3was able to efficiently degrade Rhodamine B (RhB) and eosin sodium salt under simulated solar irradiation. [ABSTRACT FROM AUTHOR]

We report here the preparation of flower-like Bi2WO6viaa simple, rapid, microwave-assisted solution-phase process. Powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HRTEM) were employed to characterize the phase and morphologies of the products. The time-dependent experiments showed an Ostwald ripening mechanism in the crystal growth process. The as-prepared Bi2WO6was able to efficiently degrade Rhodamine B (RhB) under visible light irradiation. Calcination was found to decrease the photocatalytic performance of flower-like Bi2WO6. [ABSTRACT FROM AUTHOR]

The Dapingliang Cu deposit is located at the eastern part of the Kuruketage block in NW China. Igneous rocks are widely distributed in the district and skarn are formed at the contact zone between igneous rocks and the carbonates of Beiyixi Formation. The ore is distributed in the skarn. Zircon U-Pb isotopic ages of the plagiogranite, which is related to the Cu deposit, indicate that the lower and upper intercept ages are 826 ± 23 Ma and 1886 ± 61 Ma, respectively. The lower intercept age corresponds to a weighted mean Pb/U age of 826 ± 13 Ma, yielded by ten analysis points. The upper intercept age may represent the age of the source rock, from which the plagiogranite originated. Re-Os isotopic analysis of six molybdenite samples from L7 orebody in the Dapingliang deposit shows an isochron age of 830 ± 26 Ma, which corresponds to the weighted mean model age of 829.4 ± 9.5 Ma. The concordant ages obtained by zircon U-Pb dating and molybdenite Re-Os dating are compatible with the skarn-type mineralization at Dapingling and confirm that the deposit formed during the Tarim orogeny. [ABSTRACT FROM AUTHOR]

Well-aligned Zn2GeO4nanorod bundles were successfully prepared viaa facile microwave-assisted solution-phase approach. The phase and morphology of the product were characterized by powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM). Such rhombohedral phase Zn2GeO4bundle-like microstructures were found to be constructed by abundant single crystalline nanorods of 40–70 nm in diameter and ∼800 nm in length. Some influencing factors such as the reaction time, temperature, the volume of ethylenediamine and PEG-400 were revealed to play crucial roles in the formation of Zn2GeO4nanobundles. A possible growth mechanism was proposed based on the experimental results. Moreover, the photocatalytic properties of as-prepared Zn2GeO4nanobundles were studied, and they exhibited excellent photocatalytic activities for degradation of methyl orange and rhodamine B under UV light irradiation. [ABSTRACT FROM AUTHOR]

Epigenetics refers to the study of heritable changes in gene expression or cellular phenotype without changes in DNA sequence. Epigenetic regulation of gene expression is accomplished by DNA methylation, histone modifications, histone variants, chromatin remodeling, and may involve small RNAs. DNA methylation at cytosine is carried out by enzymes called DNA Methyltransferases and is involved in many cellular processes, such as silencing of transposable elements and pericentromeric repeats, X-chromosome inactivation and genomic imprinting, etc. Histone modifications refer to posttranslational covalent attachment of chemical groups onto histones such as phosphorylation, acetylation, and methylation, etc. Histone variants, the non-canonical histones with amino acid sequences divergent from canonical histones, can have different epigenetic impacts on the genome from canonical histones. Higher-order chromatin structures maintained or modified by chromatin remodeling proteins also play important roles in regulating gene expression. Small non-coding RNAs play various roles in the regulation of gene expression at pre- as well as posttranscriptional levels. A special issue of Molecular Plant on ‘Epigenetics and Plant Development’ (Volume 4, Number 2, 2009) published a variety of articles covering many aspects of epigenetic regulation of plant development. We have tried here to present a bird's-eye view of these credible efforts towards understanding the mysterious world of epigenetics. The majority of the articles are about the chromatin modifying proteins, including histone modifiers, histone variants, and chromatin remodeling proteins that regulate various developmental processes, such as flowering time, vernalization, stem cell maintenance, and response to hormonal and environmental stresses, etc. Regulation of expression of seed transcriptome, involvement of direct tandem repeat elements in the PHE1 imprinting in addition to PcG proteins activity, paramutation, and epigenetic barriers in species hybridization are described well. The last two papers are about the Pol V-mediated heterochromatin formation independent of the 24nt-siRNA and the effect of genome position and tissue type on epigenetic regulation of gene expression. These findings not only further our current understanding of epigenetic mechanisms involved in many biological phenomena, but also pave the path for the future work, by raising many new questions that are discussed in the following lines. [ABSTRACT FROM PUBLISHER]

In the present paper, we report successful synthesis of FeMoO4hierarchical hollow spheres with 1.0 µm in diameter viaa simple, rapid and reliable microwave-assisted solution-phase approach. The phases and morphologies of the products have been characterized by powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Some factors influencing the morphology of the final product have been investigated. These experiments indicate that the self-assembly of FeMoO4nanoparticles at the water/gas interface is responsible for the formation of a hierarchical hollow structure. [ABSTRACT FROM AUTHOR]

Root hairs of Arabidopsis roots develop on trichoblasts located over the anticlinal (radial) walls of underlying cortical cells. Non-hair cells, on the other hand, develop on atrichoblasts overlying the periclinal (tangential) walls of cortical cells. Dark-grown wild-type seedlings, which produce little ethylene, are largely root hairless. Exogenous treatment of dark-grown plants with either ethylene or 1-aminocyclopropane-1-carboxylic acid (ACC) restores the development of root hairs in cells overlying the anticlinal cortical cell walls, indicating that cells in this position are more sensitive to ethylene than atrichoblasts. We used mutations in genes that overproduce ethylene (eto1, eto2, eto3 and eto4) to illustrate the positive regulatory role of ethylene. The preferential development of root hairs on epidermal cells overlying the cortical anticlinal cell walls in these mutants also illustrates that trichoblasts are more sensitive to ethylene than atrichoblasts. CTR1 is a negative regulator of the ethylene response and might, therefore, be a candidate regulator of differential sensitivity. CTR1 mRNA is expressed in all cell types in the root, suggesting that its transcriptional pattern alone cannot account for the differential sensitivity of epidermal cells to ethylene. Cellular mapping of wild-type and mutant roots supports previous findings indicating that ethylene acts after, and perhaps independently, of TTG during the establishment of cell fate in the root epidermis. [ABSTRACT FROM AUTHOR]

Fast radio bursts (FRBs) are usually suggested to be associated with mergers of compact binaries consisting of white dwarfs (WDs), neutron stars (NSs), or black holes (BHs). We test these models by fitting the observational distributions in both redshift and isotropic energy of 22 Parkes FRBs, where, as usual, the rates of compact binary mergers (CBMs) are connected with cosmic star formation rates by a power-law distributed time delay. It is found that the observational distributions can well be produced by the CBM model with a characteristic delay time from several tens to several hundreds of megayears and an energy function index 1.2 ≲ γ ≲ 1.7, where a tentative fixed spectral index β = 0.8 is adopted for all FRBs. Correspondingly, the local event rate of FRBs is constrained to for an adopted minimum FRB energy of Emin = 3 × 1039 erg, where fb is the beaming factor of the radiation, is the duration of each pointing observation, and is the sky area of the survey. This event rate, about an order of magnitude higher than the rates of NS–NS/NS–BH mergers, indicates that the most promising origin of FRBs in the CBM scenario could be mergers of WD–WD binaries. Here a massive WD could be produced since no FRB was found to be associated with an SN Ia. Alternatively, if all FRBs can repeat on a timescale much longer than the period of current observations, then they could also originate from a young active NS that forms from relatively rare NS–NS mergers and accretion-induced collapses of WD–WD binaries. [ABSTRACT FROM AUTHOR]

The hyperluminous X-ray source (HLX-1, peak X-ray luminosity ) near the spiral galaxy ESO 243-49, which underwent recurrent outbursts within a period of ∼400 days, is possibly the best candidate for an intermediate mass black hole (IMBH). The physical reason for this quasiperiodic variability is still unclear. We explore the possibility of radiation-pressure instability in the accretion disk by modeling the light curve of HLX-1, and find that it can roughly reproduce the duration, period, and amplitude of the recurrent outbursts in HLX-1 with an IMBH of . Our result provides a possible mechanism to explain the recurrent outbursts in HLX-1. We further find a universal correlation between the outburst duration and the bolometric luminosity for the black hole (BH) sources with a very broad mass range (e.g., X-ray binaries, HLX-1, and active galactic nuclei), which is roughly consistent with the prediction of radiation-pressure instability of the accretion disk. These results imply that “heartbeat” oscillations triggered by radiation-pressure instability may appear in different-scale BH systems. [ABSTRACT FROM AUTHOR]