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Summary: Dynamic DNA methylation regulatory networks are involved in many biological processes. However, how DNA methylation patterns change during flower senescence and their relevance with gene expression and related molecular mechanism remain largely unknown.Here, we used whole genome bisulfite sequencing to reveal a significant increase of DNA methylation in the promoter region of genes during natural and ethylene‐induced flower senescence in carnation (Dianthus caryophyllus L.), which was correlated with decreased expression of DNA demethylase gene DcROS1. Silencing of DcROS1 accelerated while overexpression of DcROS1 delayed carnation flower senescence.Moreover, among the hypermethylated differentially expressed genes during flower senescence, we identified two amino acid biosynthesis genes, DcCARA and DcDHAD, with increased DNA methylation and reduced expression in DcROS1 silenced petals, and decreased DNA methylation and increased expression in DcROS1 overexpression petals, accompanied by decreased or increased amino acids content. Silencing of DcCARA and DcDHAD accelerates carnation flower senescence. We further showed that adding corresponding amino acids could largely rescue the senescence phenotype of DcROS1, DcCARA and DcDHAD silenced plants.Our study not only demonstrates an essential role of DcROS1‐mediated remodeling of DNA methylation in flower senescence but also unravels a novel epigenetic regulatory mechanism underlying DNA methylation and amino acid biosynthesis during flower senescence. [ABSTRACT FROM AUTHOR]

Summary: Maize (Zea mays) is an important cereal crop with suitable stalk formation which is beneficial for acquiring an ideal agronomic trait to resist lodging and higher planting density. The elongation pattern of stalks arises from the variable growth of individual internodes driven by cell division and cell expansion comprising the maize stalk. However, the spatiotemporal dynamics and regulatory network of the maize stalk development and differentiation process remain unclear. Here, we report spatiotemporally resolved transcriptomes using all internodes of the whole stalks from developing maize at the elongation and maturation stages. We identified four distinct groups corresponding to four developmental zones and nine specific clusters with diverse spatiotemporal expression patterns among individual internodes of the stalk. Through weighted gene coexpression network analysis, we constructed transcriptional regulatory networks at a fine spatiotemporal resolution and uncovered key modules and candidate genes involved in internode maintenance, elongation, and division that determine stalk length and thickness in maize. Further CRISPR/Cas9‐mediated knockout validated the function of a cytochrome P450 gene, ZmD1, in the regulation of stalk length and thickness as predicted by the WGCN. Collectively, these results provide insights into the high genetic complexity of stalk development and the potentially valuable resources with ideal stalk lengths and widths for genetic improvements in maize. [ABSTRACT FROM AUTHOR]

Summary: The various combinations and regulations of different subunits of phosphatase PP2A holoenzymes underlie their functional complexity and importance. However, molecular mechanisms governing the assembly of PP2A complex in response to external or internal signals remain largely unknown, especially in Arabidopsis thaliana.We found that the phosphorylation status of Bβ of PP2A acts as a switch to regulate the activity of PP2A. In the absence of ethylene, phosphorylated Bβ leads to an inactivation of PP2A; the substrate EIR1 remains to be phosphorylated, preventing the EIR1‐mediated auxin transport in epidermis, leading to normal root growth.Upon ethylene treatment, the dephosphorylated Bβ mediates the formation of the A2–C4–Bβ protein complex to activate PP2A, resulting in the dephosphorylation of EIR1 to promote auxin transport in epidermis of elongation zone, leading to root growth inhibition.Altogether, our research revealed a novel molecular mechanism by which the dephosphorylation of Bβ subunit switches on PP2A activity to dephosphorylate EIR1 to establish EIR1‐mediated auxin transport in the epidermis in elongation zone for root growth inhibition in response to ethylene. [ABSTRACT FROM AUTHOR]

Summary: Polycomb dictates developmental programs in higher eukaryotes, including flowering plants. A phytohormone, abscisic acid (ABA), plays a pivotal role in seed and seedling development and mediates responses to multiple environmental stresses, such as salinity and drought.In this study, we show that ABA affects the Polycomb Repressive Complex 2 (PRC2)‐mediated Histone H3 Lys 27 trimethylation (H3K27me3) through VIN3‐LIKE1/VERNALIZATION 5 (VIL1/VRN5) to fine‐tune the timely repression of ABSCISIC ACID INSENSITIVE 3 (ABI3) and ABSCISIC ACID INSENSITIVE 4 (ABI4) in Arabidopsis thaliana.vil1 mutants exhibit hypersensitivity to ABA during early seed germination and show enhanced drought tolerance.Our study revealed that the ABA signaling pathway utilizes a facultative component of the chromatin remodeling complex to demarcate the level of expression of ABA‐responsive genes. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are one of the most promising next‐generation energy storage technologies due to their high theoretical energy and low cost. However, Li–S cells with practically high energy still suffer from a very limited cycle life with reasons which remain unclear. Here, through cell study under practical conditions, it is proved that an internal short circuit (ISC) is a root cause of early cell failure and is ascribed to the crosstalk between the S cathode and Li anode. The cathode topography affects S reactions through influencing the local resistance and electrolyte distribution, particularly under lean electrolyte conditions. The inhomogeneous reactions of S cathodes are easily mirrored by the Li anodes, resulting in exaggerated localized Li plating/stripping, Li filament formation, and eventually cell ISC. Manipulating cathode topography is proven effective to extend the cell cycle life under practical conditions. The findings of this work shed new light on the electrode design for extending cycle life of high‐energy Li–S cells, which are also applicable for other rechargeable Li or metal batteries. [ABSTRACT FROM AUTHOR]

When carrying out engineering constructions in a mountainous area with complex geological conditions, high fill slopes commonly need to be strengthened. At present, several of the main supporting structures have unique defects and shortcomings when used in the reinforcement of high fill slopes. Therefore, this paper proposes to apply a prestressed anchor cable‐pile‐slab wall structure to high fill slope support engineering, relying on the long‐term monitoring results of an actual project and using the finite difference finite element software FLAC3D to model the supporting structure. The displacement of the slope, the earth pressure behind the pile, the internal force of the supporting structure and the distribution of the anchor cable force are analyzed comprehensively and systematically. The analysis and study show that the prestressed anchor cable‐pile‐slab wall supporting structure can effectively strengthen a filled slope and control its horizontal displacement to improve its overall stability. The analysis results are used to optimize and improve this approach, which provides a new direction for the reinforcement of high fill slopes, and the results can provide a better reference for the reinforcement and design of fill slopes. [ABSTRACT FROM AUTHOR]

Combined radial–axial magnetic bearings (MBs) use a common bias magnetic circuit to provide radial and axial bias magnetic flux. Different from separate MBs, there is a constraint relation between the radial and axial bias flux. Meanwhile, there is also a constraint relationship between the radial and axial maximum bearing capacity. Therefore, the design method for separated MB is not suitable for a combined radial‐axial MB (CRAMB). In this study, a design method of the CRAMB based on an asymmetric factor was proposed. The definition of the asymmetric factor was proposed. In order to avoid the radial and axial magnetic flux into the weak magnetic field and saturation region, the optimum range of the asymmetric factor is analysed. The influence of the asymmetry factor on stiffness is analysed; the prototype designed by this method can run stably. The validity and accuracy of the design method are verified by experimental results. [ABSTRACT FROM AUTHOR]

Summary: Objective: Growing evidence has implicated dysfunction of the thalamus and its projection cortical targets in depression. However, the anatomical specificity of thalamo‐cortical connectivity in major depressive disorder (MDD) remains unknown due to the regional heterogeneity of the thalamus and limited methods to examine this. Methods: Resting‐state fMRI was collected on 70 MDD patients and 70 healthy controls. The thalamus was parcellated based on connectivity with six predefined cortical regions of interest (ROIs). The segmented thalamic nuclei were used as seeds to map connectivity with the rest of the whole brain. The cortical‐to‐thalamus connectivity values and thalamus‐based connectivity maps were compared between groups. Results: The cortical ROIs demonstrated correlations with spatially distinct zones within the thalamus. We found a trend toward reduced parietal ROI‐to‐thalamus connectivity in MDD. Importantly, MDD patients demonstrated reduced connectivity between prefrontal and parietal thalamus ROIs and bilateral middle frontal gyrus (MFG) and the right posterior default mode network (DMN) and between the prefrontal and motor thalamus ROIs and lateral temporal regions. Conversely, increased connectivity emerged between the motor thalamus ROI and right MFG and right medial frontal gyrus/anterior cingulate; between motor/somatosensory thalamus ROIs and right posterior DMN; between prefrontal/somatosensory thalamus ROIs and cerebellum; and between the parietal thalamus ROI and left insula. Conclusions: This study is the first to examine the anatomical specificity of thalamo‐cortical connectivity disturbances in MDD. Subjects with MDD demonstrated altered thalamo‐cortical connectivity characterized by a complex pattern of region‐dependent hypo‐ or hyperconnectivity. We therefore speculate that selectively modulating the connectivity of thalamo‐cortical circuitry may be a potential novel therapeutic mechanism for MDD. [ABSTRACT FROM AUTHOR]

Aims/Introduction To investigate the association between two single nucleotide polymorphisms ( SNPs; rs3774261 and rs822393) in the ADIPOQ gene and type 2 diabetes mellitus in Han Chinese from northeast China. Materials and Methods The present study comprised 993 type 2 diabetes mellitus patients and 966 unrelated controls from northeastern China. Two SNPs were sequenced using SNPscan. The distribution of genotype frequencies of the two SNPs in ADIPOQ between cases and controls, and in subgroups stratified based on body mass index, were compared using logistic regression analysis. Linear regression was used to analyze the association between each SNP and clinical indicators. Results The GG genotype of rs3774261 increased the risk of type 2 diabetes mellitus compared with the AA genotype in participants with a body mass index <24 ( P = 0.021; odds ratio 1.636, 95% CI 1.708-2.484). Rs822393 was correlated with glycosylated hemoglobin ( P = 0.043) in controls. Rs3774261 had an association with diastolic blood pressure ( P = 0.017) in controls, and in controls with a body mass index <24; rs3774261 also had an association with both systolic blood pressure ( P = 0.025) and diastolic blood pressure ( P = 0.043). Conclusions The present results confirm the association between ADIPOQ variants and type 2 diabetes mellitus in northeastern China. However, additional larger replication studies are required to validate these findings. [ABSTRACT FROM AUTHOR]

Speckle reduction is an important task in synthetic aperture radar. One extensively used approach is based on total variation (TV) regularisation, which can realise significantly sharp edges, but on the other hand brings in the undesirable staircasing artefacts. In essence, the TV‐based methods tend to create piecewise‐constant images even in regions with smooth transitions. In this study, a new method is proposed for speckle reduction via total generalised variation (TGV) penalty. This is reasonable from the fact that the TGV‐based model can reduce the staircasing artefacts of TV by being aware of higher‐order smoothness. An efficient numerical scheme based on the Nesterov's algorithm is also developed for solving the TGV‐based optimisation problem. Monte Carlo experiments show that the proposed scheme yields state‐of‐the‐art results in terms of both performance and speed. Especially when the image has some higher‐order smoothness, the authors' scheme outperforms the TV‐based methods. [ABSTRACT FROM AUTHOR]

Gamma radiation is known to induce changes in physical, optical, and structural properties in chalcogenide glasses, but previous research has focused on As2S3 and families of glasses containing Ge. For the first time, we present composition and dose dependent data on the As-S binary glass series. Binary AsxS100−x ( x = 30, 33, 36, 40, and 42) glasses were irradiated with gamma radiation using a 60Co source at 2.8 Gy/s to accumulated doses of 1, 2, 3, and 4 MGy. The irradiated samples were characterized at each dose level for density, refractive index, X-ray diffraction ( XRD), and Raman spectrum. We report an initial increase in density followed by a decrease as a function of dose that contradicts the expected compositional dependence of molar volume of these glasses. This unusual behavior is explained based on microvoid formation and nanoscale phase-separation induced by the irradiation. XRD, Raman, and electron spin resonance data provide supporting evidence, underscoring the importance of optimally- or overly constrained structures for stability under irradiation. [ABSTRACT FROM AUTHOR]

High-density (∼8 g/cm3) heavy metal oxide glasses composed of PbO, Bi2O3, and Ga2O3 were produced, and refractivity parameters (refractive index and density) were computed and measured. Refractive indices were measured at six discrete wavelengths from 0.633 to 10.59 μm using a prism coupler, and data were fitted to the Sellmeier expression. Optical basicity was computed using three models—average electronegativity, ionic-covalent parameter, and energy gap—and the results were used to compute oxygen polarizability and subsequently the refractive index. Single oscillator energy and dispersion energy were calculated from experimental indices and from oxide energy parameters. The predicted glass index dispersion based on oxide oscillator parameters underestimates the measured index by only 3%–4%. The predicted glass index from optical basicity, based on oxide energy gaps, underpredicts the index at 0.633 μm by only 2%. The calculated glass energy gap based on this optical basicity overpredicts the experimental optical gap by 6%–10%. Thus, we have shown that the density, the refractive index in the visible, and the energy gap can be reasonably predicted using only composition, optical basicity values for the constituent oxides, and partial molar volume coefficients. The relative contributions of the oxides to the total polarizability were assessed, providing an additional insight into controlling the refractivity of high-index glasses. [ABSTRACT FROM AUTHOR]

It is well established that ethylene promotes female flower development in cucumber. However, little is known about how the gaseous hormone selectively affects female flowers, and what mechanism it uses. Previously, we found organ-specific DNA damage in the primordial anther of female cucumber flowers. This finding led to a hypothesis that ethylene might promote female flower development via the organ-specific induction of DNA damage in primordial anthers. In this study, we tested this hypothesis first by demonstrating ethylene induction of DNA damage via the ethylene signaling pathway using cucumber protoplasts. Then, using representative component genes of the ethylene signaling pathway as probes, we found that one of the ethylene receptors, CsETR1, was temporally and spatially downregulated in the stamens of stage-6 female cucumber flowers, especially along with the increase of the nodes. Furthermore, by constructing transgenic Arabidopsis plants with organ-specific expression of antisense CsETR1 under the control of an AP3 promoter to downregulate ETR1 expression in the stamens, we generated Arabidopsis ‘female flowers’, in which the abnormal stamens mimic those of female cucumber flowers. Our data suggest that ethylene perception is involved in the arrest of stamen development in female cucumber flowers through the induction of DNA damage. This opens up a novel perspective and approach to solve the half-century-long puzzle of how gaseous ethylene selectively promotes female flowers in the monoecious cucumber plant. [ABSTRACT FROM AUTHOR]

Abstract: Cytokine-induced suppressor of cytokine signaling (SOCS) proteins function as feedback inhibitors of cytokine receptor signaling by inhibiting the Janus kinase–signal transducer and activator of transcription (JAK–STAT) signal transduction pathway. In this report, microtubule-associated protein 1S (MAP1), a member of the MAP1 family, was identified as a novel SOCS3 interacting protein. MAP1S could bind with microtubules and actin, and decorated and stabilized microtubules. A perinuclear co-localization was discovered between MAP1S and SOCS3. In MAP1S deficient macrophages, inhibition of SOCS3 on STAT3 phosphorylation can be partially hindered in the presence of interleukin-6 (IL-6) and lipopolysaccharide (LPS). The microtubule-depolymerizing drug nocodazole also disrupted the inhibitory activity of the SOCS3 protein. These results suggest that the interaction of SOCS3 with MAP1S and the integrity of the microtubule cytoskeleton play an important role in the negative regulation of SOCS3 on IL-6 signaling. Structured summary: MINT-6796998: SOCS3 (uniprotkb:O35718) physically interacts (MI:0218) with MAP1S (uniprotkb:Q66K74) by anti bait coimmunoprecipitation (MI:0006) MINT-6796957: SOCS3 (uniprotkb:O14543) physically interacts (MI:0218) with MAP1S (uniprotkb:Q66K74) by pull down (MI:0096) MINT-6796909, MINT-6796875, MINT-6796894, MINT-6796936: SOCS3 (uniprotkb:O14543) physically interacts (MI:0218) with MAP1S (uniprotkb:Q66K74) by two hybrid (MI:0018) MINT-6797017: MAP1S (uniprotkb:Q8C052) physically interacts (MI:0218) with SOCS3 (uniprotkb:O35718) by anti bait coimmunoprecipitation (MI:0006) MINT-6796979: MAP1S (uniprotkb:Q66K74) and SOCS3 (uniprotkb:O14543) colocalize (MI:0403) by fluorescence microscopy (MI:0416) [Copyright &y& Elsevier]

T1-weighted brain magnetic resonance imaging revealed abnormal, symmetric signals in the cerebellar dentate nucleus (G) as well as white matter degeneration (H). Parkinsonism can occur in patients with CTX (prevalence, ~9%).[1] The neurological signs are restricted to parkinsonism and misdiagnosed with Parkinson's disease in some patients. Furthermore, brain susceptibility-weighted imaging and quantitative susceptibility mapping revealed bilateral iron deposition, which suggests postsynaptic disruption of the striatal dopaminergic loop as causal to his parkinsonism. [Extracted from the article]

In the title compound, C(16)H(18)N(4)O(3)·2H(2)O, the dihedral angle between the pyrrole and pyridine rings in the hydrazone mol-ecule is 7.12 (3)°. In the crystal structure, inter-molecular N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds link the hydrazone and water mol-ecules into double layers parallel to (101). The crystal packing exhibits weak π-π inter-actions between the pyrrole and pyridine rings of neighbouring hydrazone mol-ecules [centroid-centroid distance = 3.777 (3) Å]. The crystal studied was a non-merohedral twin, the refined ratio of twin domains being 0.73 (3):0.27 (3).

In the title compound, C(19)H(26)N(2) (2+)·2Cl(-), the piperazinediium ring exhibits a chair conformation. The dihedral angle between the two benzene ring planes is 76.45 (13)°. Both amine-group H atoms participate in hydrogen bonding with the two Cl atoms.