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We study the hard Lefschetz property on compact symplectic solvmanifolds, i.e., compact quotients M = ΓG of a simply-connected solvable Lie group G by a lattice Γ, admitting a symplectic structure. [ABSTRACT FROM AUTHOR]

In this paper, we study the symplectic cohomologies and symplectic harmonic forms. Based on this, we establish a vanishing theorem on the L 2 harmonic forms on some complete symplectic manifolds. [ABSTRACT FROM AUTHOR]

We propose a 3-D transient electromagnetic inversion method based on explicit finite-difference forward modeling. For forward modeling, we calculate the whole-space initial field excited by magnetic dipole sources at an initial time after the current is switched off and apply Maxwell's equations on time using the modified DuFort–Frankel method and staggered grids. For inversion, we use the least squares optimization method. We test the inversion method using synthetic and field data. The conductivity brick is recovered well in synthetic. The inversion results of field data are consistent with the known geological conditions. The synthetic and field examples show that the inversion method based on explicit finite-difference forward modeling is effective. [ABSTRACT FROM AUTHOR]

Catalytic C-H bond activation is one of the backbones of the chemical industry. Supported metal subnanoclusters consisting of a few atoms have shown attractive properties for heterogeneous catalysis. However, the creation of such catalyst systems with high activity and excellent anti-sintering ability remains a grand challenge. Here, we report on alkali ion-promoted Pd subnanoclusters supported over defective γ-Al2O3 nanosheets, which display exceptional catalytic activity for C-H bond activation in the benzene oxidation reaction. The presence of Pd subnanoclusters is verified by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. This catalyst shows excellent catalytic activity, with a turnover frequency of 280 h−1 and yield of 98%, in benzene oxidation reaction to give phenol under mild conditions. Moreover, the introduction of alkali ion greatly retards the diffusion and migration of metal atoms when tested under high-temperature sintering conditions. Density functional theory (DFT) calculations reveal that the addition of alkali ion to Pd nanoclusters can significantly impact the catalyst's structure and electronic properties, and eventually promote its activity and stability. This work sheds light on the facile and scalable synthesis of highly active and stable catalyst systems with alkali additives for industrially important reactions. [ABSTRACT FROM AUTHOR]

There were good clinical outcomes of drug-eluting balloon (DEB) use in de novo lesions and in-stent restenosis (ISR) lesions. However, few studies focused on DEB use in patients with acute myocardial infarction (AMI). The aim of this study was to retrospective evaluate the efficacy of DEB for patients of AMI with de novo small coronary artery disease. Between March 2016 and March 2018, patients of AMI with de novo small coronary artery (reference diameter 2.0-2.8 mm) and received percutaneous coronary intervention (PCI) were enrolled. 268 patients were divided into DEB group (PCI with further DEB, n = 56) and drug-eluting stent (DES) group (PCI with further DES, n = 212). The primary endpoint was major adverse cardiac events (MACE; all-cause death, non-fatal myocardial infarction, target lesion revascularization and target vessel revascularization) at 24 months. A subset of patients underwent angiographic follow-up. Clinical characteristics were balanced in the two groups. Mean reference vessel diameter was similar between the DEB and DES groups (2.64 ± 0.17 mm vs 2.65 ± 0.14 mm, P = 0.625). The 24-month MACE rates were 17.5% in DEB group and 16.4% in DES group (P = 0.853). Stent thrombosis was seen in three patients (1.46%) in DES group. There was no vessel thrombosis noted in the DEB group. Angiographic follow-up was performed in 35.71% of DEB group and 27.25% of DES group. Late lumen loss was similar between the two groups (DEB 0.14 ± 0.13 mm, DES 0.19 ± 0.12 mm, P = 0.442). DEB is a reasonable strategy for AMI with small coronary artery. Compared with DES, DEB is an alternative strategy which had similar 24-month clinical outcomes. [ABSTRACT FROM AUTHOR]

The activation of microglia is a hallmark of neuroinflammation and contributes to various neurodegenerative diseases. Chronic inorganic arsenic exposure is associated with impaired cognitive ability and increased risk of neurodegeneration. The present study aimed to investigate whether chronic inorganic arsenic-induced learning and memory impairment was associated with microglial activation, and how organic (DMAV 600 μM, MMAV 0.1 μM) and inorganic arsenic (NaAsO2 0.6 μM) affect the microglia. Male C57BL/6J mice were divided into two groups: a control group and a group exposed to arsenic in their drinking water (50 mg/L NaAsO2 for 24 weeks). The Morris water maze was performed to analyze neuro-behavior and transmission electron microscopy was used to assess alterations in cellular ultra-structures. Hematoxylin–eosin and Nissl staining were used to observe pathological changes in the cerebral cortex and hippocampus. Flow cytometry was used to reveal the polarization of the arsenic-treated microglia phenotype and GC-MS was used to assess metabolomic differences in the in vitro microglia BV-2 cell line model derived from mice. The results showed learning and memory impairments and activation of microglia in the cerebral cortex and dentate gyrus (DG) zone of the hippocampus, in mice chronically exposed to arsenic. Flow cytometry demonstrated that BV-2 cells were activated with the treatment of different arsenic species. The GC-MS data showed three important metabolites to be at different levels according to the different arsenic species used to treat the microglia. These included tyrosine, arachidonic acid, and citric acid. Metabolite pathway analysis showed that a metabolic pathways associated with tyrosine metabolism, the dopaminergic synapse, Parkinson's disease, and the citrate cycle were differentially affected when comparing exposure to organic arsenic and inorganic arsenic. Organic arsenic MMAV was predominantly pro-inflammatory, and inorganic arsenic exposure contributed to energy metabolism disruptions in BV-2 microglia. Our findings provide novel insight into understanding the neurotoxicity mechanisms of chronic arsenic exposure and reveal the changes of the metabolome in response to exposure to different arsenic species in the microglia. [ABSTRACT FROM AUTHOR]

For a complete symplectic manifold M 2 n , we define the L 2 -hard Lefschetz property on M 2 n . We also prove that the complete symplectic manifold M 2 n satisfies L 2 -hard Lefschetz property if and only if every class of L 2 -harmonic forms contains a L 2 symplectic harmonic form. As an application, we get if M 2 n is a closed symplectic parabolic manifold which satisfies the hard Lefschetz property, then its Euler characteristic satisfies the inequality (- 1) n χ (M 2 n) ≥ 0 . [ABSTRACT FROM AUTHOR]

Endometrial cancer is one of the most prevalent tumors of the female reproductive system causing serious health effects to women worldwide. Although numerous studies, including analysis of gene expression profile and cellular microenvironment have been reported in this field, pathogenesis of this disease remains unclear. In this study, we performed a system bioinformatics analysis of endometrial cancer using the Gene Expression Omnibus (GEO) datasets (GSE17025, GSE63678, and GSE115810) to identify the core genes. In addition, exosomes derived from endometrial cancer cells were also isolated and identified. First, we analyzed the differentially expressed genes (DEGs) between endometrial cancer tissues and normal tissues in clinic samples. We found that HAND2-AS1, PEG3, OGN, SFRP4, and OSR2 were co-expressed across all 3 datasets. Pathways analysis showed that several pathways associated with endometrial cancer, including "p53 signaling pathway", "Glutathione metabolism", "Cell cycle", and etc. Next, we selected DEGs with highly significant fold change and co-expressed across the 3 datasets and validated them in the TCGA database using Gene Expression Profiling Interactive Analysis (GEPIA). Finally, we performed a survival analysis and identified four genes (TOP2A, ASPM, EFEMP1, and FOXL2) that play key roles in endometrial cancer. We found up-regulation of TOP2A and ASPM in endometrial cancer tissues or cells, while EFEMP1 and FOXL2 were down-regulated. Furthermore, we isolated exosomes from the culturing supernatants of endometrial cancer cells (Ishikawa and HEC-1-A) and found that miR-133a, which regulates expression of FOXL2, were present in exosomes and that they could be delivered to normal endometrial cells. The common DEGs, pathways, and exosomal miRNAs identified in this study might play an important role in progression as well as diagnosis of endometrial cancer. In conclusion, our results provide insights into the pathogenesis and risk assessment of endometrial cancer. Even so, further studies are required to elucidate on the precise mechanism of action of these genes in endometrial cancer. [ABSTRACT FROM AUTHOR]

Aims: Circulating endothelial progenitor cells (EPCs) play a key role in maintaining endothelial function. Dysfunction of EPCs is associated with the cardiovascular complication of diabetes. The purpose of this study is to investigate the direct effects of hyperinsulinemia on EPCs and the underlying mechanisms. Methods: EPCs isolated from healthy adults were cultured with various concentrations of insulin (control group, without insulin; physiological insulin group, 10 nM insulin and hyperinsulinemia group, 100 nM insulin) with or without phosphatidylinositol-3-kinase (PI3-K) inhibitor (LY294002, 5 µM), endothelial nitric oxide synthase (eNOS) inhibitor (l-NG-nitro-arginine methyl ester (l-NAME), 100 µM), sodium nitroprusside (SNP, 25 µM), p38 mitogen-activated protein kinase(MAPK) inhibitor (SB203580, 5 µM) or extracellular signal-regulated kinases (ERK) 1/2 inhibitor (PD98059, 10 µM). Proliferation, tube formation, and apoptosis of EPCs were determined. Expressions of eNOS, PI3-K, protein kinase B (Akt), p38 MAPK, and ERK 1/2 were assessed. Results: Hyperinsulinemia caused a significant decrease in proliferation and tube formation abilities than control group. Hyperinsulinemia increased apoptosis rate of EPCs than control group. Furthermore, hyperinsulinemia downregulated phosphorylation of eNOS, PI3-K and Akt, and upregulated phosphorylation of p38 MAPK and ERK. SNP could restore impaired tube formation induced by hyperinsulinemia. P38 MAPK inhibitor but not ERK inhibitor could decrease apoptosis induced by hyperinsulinemia. Conclusion: Hyperinsulinemia impaired EPCs' tube formation ability by downregulation of PI-3K/Akt/eNOS pathway. Hyperinsulinemia induced apoptosis of EPCs via upregulation of p38 MAPK. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the existence of J-holomorphic curves on almost Hermitian manifolds. Let (M, g, J, F) be an almost Hermitian manifold and f:Σ→M be an injective immersion. We prove that if the Lp functional has a critical point or a stable point in the same almost Hermitian class, then the immersion is J-holomorphic. [ABSTRACT FROM AUTHOR]

Deepwater sediments are prone to loss circulation in drilling due to a low overburden gradient. How to predict the magnitude of leak-off pressure more accurately is an important issue in the protection of drilling safety and the reduction of drilling cost in deep water. Starting from the mechanical properties of a shallow formation and based on the basic theory of rock-soil mechanics, the stress distribution around a borehole was analyzed. It was found that the rock or soil on a borehole is in the plastic yield state before the effective tensile stress is generated, and the effective tangential and vertical stresses increase as the drilling fluid density increases; thus, tensile failure will not occur on the borehole wall. Based on the results of stress calculation, two mechanisms and leak-off pressure prediction models for shallow sediments in deepwater drilling were put forward, and the calculated values of these models were compared with the measured value of shallow leak-off pressure in actual drilling. The results show that the MHPS (minimum horizontal principle stress) model and the FIF (fracturing in formation) model can predict the lower and upper limits of leak-off pressure. The PLC (permeable lost circulation) model can comprehensively analyze the factors influencing permeable leakage and provide a theoretical basis for leak-off prevention and plugging in deepwater drilling. [ABSTRACT FROM AUTHOR]

Contagious ecthyma, caused by orf virus (ORFV), is an epitheliotrophic contagious disease with zoonotic implications that mainly affects sheep, goats, wild ruminants, and humans. Recently, a novel ORFV strain, OV/HLJ/04, was successfully isolated from the skin and mucosal lesions of a goat with severe clinical sore mouth symptoms in Heilongjiang province of China. The OV/HLJ/04 isolate was characterized by electron microscopy, serological tests, and experimental reproduction of disease. The purified virions exhibited a typical ovoid shape when observed by electron microscopy. Moreover, experimental reproduction of disease showed that a lamb developed typical clinical signs of contagious ecthyma, such as severe vascular proliferation, when inoculated with the virus. Subsequently, amplification of ORFV011 ( B2L) gene fragments of viral DNA by polymerase chain reaction (PCR) and gene sequencing were performed. Phylogenetic analysis of the B2L protein gene revealed that this strain clusters with ORFV strains from epidemic-stricken areas worldwide, including recent mainland China isolates. Analysis using ClustalW MegAlign in DNAStar indicated that OV/HLJ/04 (GenBank: KU523790.1) was genetically closely related to the isolates Gansu (JQ904789), with 99.7% identity; NZ2 (DQ184476), with 97.4% identity; and Xinjiang (KF666560), with 90.6% identity. These results may provide insights into the genotype of the etiological agent responsible for the orf outbreak in Heilongjiang Province. [ABSTRACT FROM AUTHOR]

In this paper, we calculate the dimension of the J-anti-invariant cohomology subgroup $$H_J^-$$ on $${\mathbb {T}}^4$$ . Inspired by the concrete example, $${\mathbb {T}}^4$$ , we get that: on a closed symplectic 4-dimensional manifold $$(M, \omega )$$ , $$h^-_J=0$$ for generic $$\omega $$ -compatible almost complex structures. [ABSTRACT FROM AUTHOR]

We previously found that hematoma worsens hydrocephalus after intraventricular hemorrhage (IVH) via increasing iron deposition and aggravating ependymal cilia injury; therefore, promoting hematoma absorption may be a promising strategy for IVH. Recently, some investigations imply that simvastatin has the ability of accelerating hematoma absorption. Thus, this study was designed to examine the efficacy of simvastatin for IVH in rats. Intracerebral hemorrhage with ventricular extension was induced in adult male Sprague-Dawley rats after autologous blood injection. Simvastatin or vehicle was administered orally at 1 day after IVH and then daily for 1 week. MRI studies were performed to measure the volumes of intracranial hematoma and lateral ventricle at days 1, 3, 7, 14, and 28 after IVH. Motor and neurocognitive functions were assessed at days 1 to 7 and 23 to 28, respectively. Iron deposition, iron-related protein expression, ependymal damage, and histology were detected at day 28. Expression of CD36 scavenger receptor (facilitating phagocytosis) was examined at day 3 after IVH using western blotting and immunofluorescence. Simvastatin significantly increased hematoma absorption ratio, reduced ventricular volume, and attenuated neurological dysfunction post-IVH. In addition, less iron accumulation and more cilia survival was observed in the simvastatin group when compared with the control. What's more, higher expression of CD36 was detected around the hematoma after simvastatin administration. Simvastatin significantly enhanced brain hematoma absorption, alleviated hydrocephalus, and improved neurological recovery after experimental IVH, which may in part by upregulating CD36 expression. Our data suggest that early simvastatin use may be a novel therapy for IVH patients. [ABSTRACT FROM AUTHOR]

The article presents a study on a field test and analytical analysis for measurements of vertical pressure at a top coal mining face at Datong Tashan Mines, China. Based on the real-time pressure monitoring of single props and hydraulic supports at a top coal mining face, intensive factors of pressure were adopted to provide a quantitative description of the mining mechanics.

In this paper, we define the generalized Lejmi's P operator on a compact almost Kähler 2 n-manifold. We get that J is C-pure and full if dim ker P = b−1. Additionally, we investigate the relationship between J -anti-invariant cohomology introduced by T.-J. Li and W. Zhang and new symplectic cohomologies introduced by L.-S. Tseng and S.-T. Yau on a closed symplectic 4-manifold. [ABSTRACT FROM AUTHOR]

For a compact symplectic manifold which is s-Lefschetz which is weaker than the hard Lefschetz property, we prove that the Lefschetz decomposition for de Rham cohomology also holds. [ABSTRACT FROM AUTHOR]

Based on recent work of T. Draghici, T.-J. Li, and W. Zhang, we further investigate properties of the dimension $$h_J^-$$ of the $$J$$ -anti-invariant cohomology subgroup $$H_J^-$$ of a closed almost Hermitian 4-manifold $$(M,g,J,F)$$ using metric compatible almost complex structures. We prove that $$h_J^-=0$$ for generic almost complex structures $$J$$ on $$M$$ . [ABSTRACT FROM AUTHOR]

Serious wellbore instability occurs frequently during horizontal drilling in shale gas reservoirs. The conventional forecast model of in situ stresses is not suitable for wellbore stability analysis in laminated shale gas formations because of the inhomogeneous mechanical properties of shale. In this study, a new prediction method is developed to calculate the in situ stresses in shale formations. The pore pressure near the borehole is heterogeneous along both the radial and tangential directions due to the inhomogeneity in the mechanical properties and permeability. Therefore, the stress state around the wellbore will vary with time after the formation is drained. Besides, based on the experimental results, a failure criterion is verified and applied to determine the strength of Silurian shale in the Sichuan Basin, including the long-term strength of gas shale. Based on this work, horizontal well borehole stability is analyzed by the new in situ stress prediction model. Finally, the results show that the collapse pressure will be underestimated if the conventional model is used in shale gas reservoirs improperly. The collapse pressure of a horizontal well is maximum at dip angle of 45°. The critical mud weight should be increased constantly to prevent borehole collapse if the borehole is exposed for some time. [ABSTRACT FROM AUTHOR]

Human thioredoxin reductase (TrxR) system is associated with cancer cell growth and anti-apoptosis process. Effects of 1,2-[bis(1,2-benzisoselenazolone-3(2H)-ketone)]ethane (BBSKE), a novel TrxR inhibitor, were investigated on human leukemia cell lines HL-60 and K562. BBSKE treatment induced cell growth inhibition and apoptosis in both cell lines. Apoptosis induced by BBSKE is through Bcl-2/Bax and caspase-3 pathways. Ehrlich’s ascites carcinoma-bearing mice were used to investigate the anti-tumor effect of BBSKE in vivo. Tumor-bearing mice treated with BBSKE showed an increase of life span with a comparable effect to cyclophosphamide (CTX). These results suggest a potential usage of BBSKE as a therapeutic agent against non-solid tumors. [ABSTRACT FROM AUTHOR]

Previously, we successfully prepared a monoclonal antibody (mAb) named 2E4, that directly recognizes the major envelope protein B2L of the orf virus (ORFV), but there is little information about its epitope. Here, we meticulously mapped the 2E4 epitope through combinatorial programs and identified the functional binding domain and a key amino acid residue. Briefly, the simulated epitope peptide closely resembles 84VDVQSKDKDADELR97 located at the N-terminus of B2L, strongly suggesting that the epitope is conformationally or spatially structure-dependent. Subsequently, we combined these findings with the results from the antigenicity prediction of B2L to design three truncated fragments of B2L (F1, F2 and F3) selected using 2E4, and only the F1 fragment was found to be eligible for the advanced stage. Alanine-scanning mutagenesis suggested that the D94 residue is structurally crucial for the 2E4 epitope. The other participating residues, including K61, E62, and D92, together with D94 were responsible for enabling 2E4 binding and served as factors that synergistically enabled binding to the whole 2E4 epitope. In this paper, we describe, for the first time, the architecture of an ORFV conformational epitope, and it is also expected that mAb 2E4 and its epitope can be used for applications relating to orf control. [ABSTRACT FROM AUTHOR]

This study armed to determine the expression of protease and pectinase in Bacillus subtilis using the herbal saponin extract as the fermentation substrates and then characterize the fermentation broths. The saponin concentration in the crude extract from four herbs reached to 25% under the extraction conditions of 60 °C, with a pH 9 for 3 h at a solid-liquid ratio of 1:18. In direct fermentation of Bacillus subtilis in the saponin extract, the maximum activities of protease and pectinase in the cell supernatant reached 3984 and 227 U/ml, respectively. Correspondingly, when 5% glucose was added to this extract for the fermentation, the two maximum activities were up to 2451 and 1390 U/ml, respectively. When characterization of the two abovementioned fermentation broths was carried out, it was observed that the luminousness values were increased to 26.9 and 39.2% from 9.7% of the initial value after 32 h of fermentation, respectively, and there was no significant change in the saponin concentration during the fermentation processes. The evaluation values of washing performance were remarkably improved by 8.2 and 21.7%, respectively. [ABSTRACT FROM AUTHOR]