[Stokes Parameter Detection and Precision Analysis Based on Rotating Quarter-Wave Plate].

The accuracy of the calibration reference source polarization states directly influences the precision of the polarized optical remote sensor calibration, and thus affects the inversion accuracy of the characteristics of targets. In this paper, 870 nm horizontal linear polarized light has been chosen as the tested calibration reference light, modulated by rotating quarter-wave plate(QWP). The intensity as a Fourier series of the rotation angle of the plate and its coefficients were demodulated with the Fourier transform method, Stokes parameters can be calculated with these coefficients. The mean, standard deviation, composite uncertainty and relative deviation of measured data compared with the theoretical value of the ten measurement results were presented. In order to improve the accuracy of the measurement, the correction model for the quarter-wave plate retardance deviation Δδ, fast axis angle deviation Δα and the transmission axis alignment deviation Δß of analyzing polarizer has been constructed. In this model, detection deviation of Stokes parameters is described as a function of Δδ and Δß, Δδ and Δß were determined by the function and magnitude of the deviation. Combined with quarter-wave plate fast axis angle deviation which was the result of simulation to adjust the experiment device, and then detecting the calibration reference source polarization states again. The experimental results show that, the difference between measured value and theoretical value of Stokes parameters reduced to less than 1.41% from 3.77% relative to without correction. The experiment principle, device and deviation correction model of this research can significantly improve the accuracy of detecting the polarization state of the calibration reference light source.

α-Glucosidase Inhibitors from the Fungus Aspergillus terreus 3.05358.

One new diketopiperazine alkaloid amauromine B (1), along with three known meroterpenoids, austalide B (2), austalides N and O (3 and 4), and two known steroids (5 and 6), was isolated and identified from the culture broth of the fungus Aspergillus terreus 3.05358. Their structures were elucidated by extensive spectroscopic techniques, including 2D-NMR and MS analysis, the absolute configuration of 1 was unambiguously established by single crystal X-ray diffraction analysis. All the isolates were evaluated for their inhibitory effects on α-glucosidase. Amauromine B (1) and austalide N (3) exhibited more potent α-glucosidase inhibitory activities than the positive control acarbose.

[Serum hydrogen sulfide levels in children with benign infantile convulsions associated with mild gastroenteritis].

OBJECTIVE: To study the changes and significance of serum hydrogen sulfide (H2S) levels in children with benign infantile convulsions associated with mild gastroenteritis (BICE). METHODS: Forty-two hospitalized children diagnosed with BICE were recruited to the observation group, and 46 children admitted due to acute gastroenteritis alone were recruited to the control group. Serum H2S levels were measured by a spectrophotometer. RESULTS: The serum H2S level in the observation group was significantly lower than in the control group (28±12 µmol/L vs 45±10 µmol/L; P<0.01). The patients with a number of convulsions greater than or equal to two had significantly lower serum H2S levels than those with a number less than two (P<0.05). The number of convulsions was negatively correlated with serum H2S level in BICE patients (r=-0.485, P=0.001). When a convulsion exceeded 5 minues in duration, the duration was negatively correlated with serum H2S level (r=-0.736, P=0.004). CONCLUSIONS: The reduction in endogenous H2S level might be one of the causes of convulsions in BICE patients. The degree of reduction in H2S level is associated with the number of convulsions and the duration of convulsion (when it exceeds 5 minues). Further investigation is needed to determine the clinical significance of these results.

Regulate transportation of ions and polysulfides in all-solid-state Li-S batteries using ordered-MOF composite solid electrolyte.

A dilemma arises when striving to balance the maximum desired ion conductivity and minimize the undesired lithium polysulfide shuttling effect for all-solid-state lithium-sulfur batteries (ASSLSBs). Here, we introduce a strategy of using ordered MIL-125-NH2 as fillers for poly(ethylene oxide)-based electrolytes to simultaneously regulate the transportation of lithium ions and polysulfides. When compared to electrolytes lacking metal-organic frameworks (MOFs) and those containing disordered MOFs, the electrolyte featuring an ordered-MOF structure, denoted as three-dimensional (3D) MPPL composite solid electrolyte (CSE), exhibits the highest ion conductivity of 8.3 × 10-4 siemens per centimeter at 60°C. As a result, pouch-type ASSLSBs with 3D MPPL CSE maintains stable cycling for 400 cycles at 0.5 C at 60°C, showcasing the successful implementation of this strategy in simultaneously regulating ion and polysulfide transport. This approach opens up alternative avenues to achieve high-performance ASSLSBs with exceptional energy density.

Mendelian randomization and transcriptome analysis identified immune-related biomarkers for osteoarthritis.

Background: The immune microenvironment assumes a significant role in the pathogenesis of osteoarthritis (OA). However, the current biomarkers for the diagnosis and treatment of OA are not satisfactory. Our study aims to identify new OA immune-related biomarkers to direct the prevention and treatment of OA using multi-omics data. Methods: The discovery dataset integrated the GSE89408 and GSE143514 datasets to identify biomarkers that were significantly associated with the OA immune microenvironment through multiple machine learning methods and weighted gene co-expression network analysis (WGCNA). The identified signature genes were confirmed using two independent validation datasets. We also performed a two-sample mendelian randomization (MR) study to generate causal relationships between biomarkers and OA using OA genome-wide association study (GWAS) summary data (cases n = 24,955, controls n = 378,169). Inverse-variance weighting (IVW) method was used as the main method of causal estimates. Sensitivity analyses were performed to assess the robustness and reliability of the IVW results. Results: Three signature genes (FCER1G, HLA-DMB, and HHLA-DPA1) associated with the OA immune microenvironment were identified as having good diagnostic performances, which can be used as biomarkers. MR results showed increased levels of FCER1G (OR = 1.118, 95% CI 1.031-1.212, P = 0.041), HLA-DMB (OR = 1.057, 95% CI 1.045 -1.069, P = 1.11E-21) and HLA-DPA1 (OR = 1.030, 95% CI 1.005-1.056, P = 0.017) were causally and positively associated with the risk of developing OA. Conclusion: The present study identified the 3 potential immune-related biomarkers for OA, providing new perspectives for the prevention and treatment of OA. The MR study provides genetic support for the causal effects of the 3 biomarkers with OA and may provide new insights into the molecular mechanisms leading to the development of OA.

Protective effect of hydrogen sulfide is mediated by negative regulation of epigenetic histone acetylation in Parkinson's disease.

Introduction: Derangements in monoaminergic transmission in the substantia nigra with disturbed signaling in the hypothalamic-pituitary-adrenal axis are the major characteristics of Parkinson's disease (PD). It has been reported that the administration of hydrogen sulfide (H2S) is in practice to treat PD because of its redundant nature in regulating various neuronal signals. Hence, the current investigation was performed to evaluate the hypothesis that H2S might exert protective action via the inhibition of epigenetic histone acetylation. Material and methods: To test this notion, 6-hydroxydopamine (6-OHDA) was used to induce PD and sodium hydrogen sulfide (SHS) was used as a H2S donor and tubastatin A (TSA) was tested in an in vivo rat model to delineate the signaling mechanism. Results: Induction of PD in rats demonstrated elevated oxidative stress with an evidenced decrease in antioxidant enzymes, while elevated pro-inflammatory cytokines and inflammatory mediators were observed in the striatum of PD rats compared to controls. On the other hand, elevated (p < 0.01) levels of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), mRNA transcript of HDAC-2, -3, -4, -6 and total histone deacetylase (HDAC) were found with reduced levels of histone acetyltransferase (HAT) in the brain tissues of PD induced rats. Conclusions: Diversely, H2S exposure reversed these alterations with reduced HDAC activity. Further, PD rats treated with HDAC inhibitor showed a dramatic upsurge in the level of tyrosine hydroxylase, with a decreased level of glial fibrillary acidic protein, α-synuclein, tumor necrosis factor α, and other cytokines. Thus the results of the study suggest that H2S exerts protection via inhibition of HDAC.

Transcriptomic analysis reveals shared gene signatures and molecular mechanisms between obesity and periodontitis.

Background: Both obesity (OB) and periodontitis (PD) are chronic non-communicable diseases, and numerous epidemiological studies have demonstrated the association between these two diseases. However, the molecular mechanisms that could explain the association between OB and PD are largely unclear. This study aims to investigate the common gene signatures and biological pathways in OB and PD through bioinformatics analysis of publicly available transcriptome datasets. Methods: The RNA expression profile datasets of OB (GSE104815) and PD (GSE106090) were used as training data, and GSE152991 and GSE16134 as validation data. After screening for differentially expressed genes (DEGs) shared by OB and PD, gene enrichment analysis, protein-protein interaction (PPI) network construction, GeneMANIA analysis, immune infiltration analysis and gene set enrichment analysis (GSEA) were performed. In addition, receiver operating characteristic (ROC) curves were used to assess the predictive accuracy of the hub gene. Finally, we constructed the hub gene-associated TF-miRNA-mRNA regulatory network. Results: We identified a total of 147 DEGs shared by OB and PD (38 down-regulated and 109 up-regulated). Functional analysis showed that these genes were mainly enriched in immune-related pathways such as B cell receptor signalling, leukocyte migration and cellular defence responses. 14 hub genes (FGR, MNDA, NCF2, FYB1, EVI2B, LY86, IGSF6, CTSS, CXCR4, LCK, FCN1, CXCL2, P2RY13, MMP7) showed high sensitivity and specificity in the ROC curve analysis. The results of immune infiltration analysis showed that immune cells such as macrophages, activated CD4 T cells and immune B cells were present at high infiltration levels in both OB and PD samples.The results of GeneMANIA analysis and GSEA analysis suggested that five key genes (FGR, LCK, FYB1, LY86 and P2RY13) may be strongly associated with macrophages. Finally, we constructed a TF-miRNA-mRNA regulatory network consisting of 233 transcription factors (TFs), 8 miRNAs and 14 mRNAs based on the validated information obtained from the database. Conclusions: Five key genes (FGR, LCK, FYB1, LY86, P2RY13) may be important biomarkers of OB and PD. These genes may play an important role in the pathogenesis of OB and PD by affecting macrophage activity and participating in immune regulation and inflammatory responses.

A Mendelian randomization study for drug repurposing reveals bezafibrate and fenofibric acid as potential osteoporosis treatments.

Background: Lipid pathways have been implicated in the pathogenesis of osteoporosis (OP). Lipid-lowering drugs may be used to prevent and treat OP. However, the causal interpretation of results from traditional observational designs is controversial by confounding. We aimed to investigate the causal association between genetically proxied lipid-lowering drugs and OP risk. Methods: We conducted two-step Mendelian randomization (MR) analyses to investigate the causal association of genetically proxied lipid-lowering drugs on the risk of OP. The first step MR was used to estimate the associations of drug target genes expression with low-density lipoprotein cholesterol (LDL-C) levels. The significant SNPs in the first step MR were used as instrumental variables in the second step MR to estimate the associations of LDL-C levels with forearm bone mineral density (FA-BMD), femoral neck BMD (FN-BMD), lumbar spine BMD (LS-BMD) and fracture. The significant lipid-lowering drugs after MR analyses were further evaluated for their effects on bone mineralization using a dexamethasone-induced OP zebrafish model. Results: The first step MR analysis found that the higher expression of four genes (HMGCR, NPC1L1, PCSK9 and PPARG) was significantly associated with a lower LDL-C level. The genetically decreased LDL-C level mediated by the PPARG was significantly associated with increased FN-BMD (BETA = -1.38, p = 0.001) and LS-BMD (BETA = -2.07, p = 3.35 × 10-5) and was marginally significantly associated with FA-BMD (BETA = -2.36, p = 0.008) and reduced fracture risk (OR = 3.47, p = 0.008). Bezafibrate (BZF) and Fenofibric acid (FBA) act as PPARG agonists. Therefore genetically proxied BZF and FBA had significant protective effects on OP. The dexamethasone-induced OP zebrafish treated with BZF and FBA showed increased bone mineralization area and integrated optical density (IOD) with alizarin red staining. Conclusion: The present study provided evidence that BZF and FBA can increase BMD, suggesting their potential effects in preventing and treating OP. These findings potentially pave the way for future studies that may allow personalized selection of lipid-lowering drugs for those at risk of OP.

MicroRNA-147 negatively regulates expression of toll-like receptor-7 in rat macrophages and attenuates pristane induced rheumatoid arthritis in rats.

Background/Introduction: Aberrant expression of Toll like receptors (TLR) plays a vital role in pathogenesis of rheumatoid arthritis (RA). Micro RNAs (miRs) could play important role in the related signaling pathways. The present study was undertaken to establish the link between miR-147 and TLR-7 in rat macrophages (in vitro) and in pristane (PS) induced arthritic rats. METHODOLOGY: Dual luciferase assay was done to confirm the interaction between miR-147 and TLR-7. The effect of miR-147 on regulation of TLR-7 was done by RT-qPCR and Immunoblotting studies in rat macrophages (ATCC® CRL-2192TM) after treating them with miR-147 mimics and inhibitors. R-848 (Imiquimod) was used as TLR-7 stimulant, the mRNA and protein expression levels of IFN-ß and TNF-α were recorded to determine the regulation of TLR-7. The levels of miR-147 and TLR-7 were evaluated during induction of rat bone marrow derived macrophage in the PS induced rat macrophages and spleens of methotrexate exposed rats. The miR-147 mimics was injected intraperitoneal to the PS treated rats and the severity of arthritis was studied. RESULTS: The study confirmed TLR-7 mRNA as the potential target of miR-147 in rats. Alterations in miR-147 by transfecting mimics or inhibitors in ATCC® CRL-2192TM cells exhibited suppression and amelioration of TLR-7 and cytokine expression. The alteration in expression of miR-147 was inversely correlated with expression of TLR-7 during bone marrow derived macrophages induction in PS exposed cells and spleens. The abnormal expression was reversed in spleens of methotrexate treated arthritic rats. The treatment of miR-147 mimic caused suppression in expression of TLR-7 and improved the severity of arthritis in PS induced arthritic rats. CONCLUSIONS: MiR-147 inversely regulates the TLR-7 signaling by targeting TLR-7 itself both in vivo and in vitro. The study provides a novel approach for conditions involving abnormal TLR-7 expression in arthritis.

Dislocation creation and void nucleation in FCC ductile metals under tensile loading: a general microscopic picture.

Numerous theoretical and experimental efforts have been paid to describe and understand the dislocation and void nucleation processes that are fundamental for dynamic fracture modeling of strained metals. To date an essential physical picture on the self-organized atomic collective motions during dislocation creation, as well as the essential mechanisms for the void nucleation obscured by the extreme diversity in structural configurations around the void nucleation core, is still severely lacking in literature. Here, we depict the origin of dislocation creation and void nucleation during uniaxial high strain rate tensile processes in face-centered-cubic (FCC) ductile metals. We find that the dislocations are created through three distinguished stages: (i) Flattened octahedral structures (FOSs) are randomly activated by thermal fluctuations; (ii) The double-layer defect clusters are formed by self-organized stacking of FOSs on the close-packed plane; (iii) The stacking faults are formed and the Shockley partial dislocations are created from the double-layer defect clusters. Whereas, the void nucleation is shown to follow a two-stage description. We demonstrate that our findings on the origin of dislocation creation and void nucleation are universal for a variety of FCC ductile metals with low stacking fault energies.

Nucleation and growth mechanisms of hcp domains in compressed iron.

In our previous work, we have pointed out that the shock-induced phase transition in iron occurs with the help of interface energy which reduces the potential barrier between two phases. Here, through studying the nucleation and growth mechanisms of hcp domains in compressed iron, we find that the flatted-octahedral-structure (FOS) is the primary structural unit of the embryo nucleus and phase interface of hcp domains, and the interfacial energy is reduced via formation of FOSs. The phase transition process can be described by the following four stages: (i) Some atoms deviate from their equilibrium positions with the aid of thermal fluctuations to form FOSs with two different deformation directions in the local region; (ii) FOSs with different deformation directions aggregate to form a thin stratified structure like twin-crystal configuration; (iii) The thin stratified structure undergoes a relative slip to form the new hcp phase; (iv) The hcp phase domain grows up through the formation of new FOSs along the phase boundary. In addition, through comparing the time evolution curves of initial single phase domain, we find that the growth rate of single phase domain depends on the loading way and its occurrence time.

Morphology and growth speed of hcp domains during shock-induced phase transition in iron.

Emergence and time evolution of micro-structured new-phase domains play a crucial role in determining the macroscopic physical and mechanical behaviors of iron under shock compression. Here, we investigate, through molecular dynamics simulations and theoretical modelings, shock-induced phase transition process of iron from body-centered-cubic (bcc) to hexagonal-close-packed (hcp) structure. We present a central-moment method and a rolling-ball algorithm to calculate and analyze the morphology and growth speed of the hcp phase domains, and then propose a phase transition model to clarify our derived growth law of the phase domains. We also demonstrate that the new-phase evolution process undergoes three distinguished stages with different time scales of the hcp phase fraction in the system.