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1.
Sci Rep ; 14(1): 11473, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769099

ABSTRACT

Currently, the utilization of coalbed methane resources in the Guizhou region faces challenges such as complex reservoir structure, high gas content, and microporous development. Based on these, the pore structure and adsorption capacity of Guizhou tectonic deformed coals (TDCs) were evaluated using a suite of integrated diagnostic techniques including low-temperature nitrogen adsorption (LT-N2A), mercury intrusion porosimetry (MIP), methane isothermal adsorption. Through the above methods, the pore structure and adsorption characteristics of the samples were characterized; The samples were divided into the range of joint pores by combining the results of MIP and LT-N2A; Using the molecular simulation software, the 2 nm, 4 nm, 10 nm pores affecting the methane endowment state were investigated respectively, and from the perspective of the heat of adsorption and energy, the concept of the three-phase transition of methane was proposed, and explore the change of the pore spacing affecting the endowment state of methane from the solid state pore to the gas state pore. The results provide new ideas for the in-depth study of gas storage in tectonic coal reservoirs in Guizhou Province.

2.
Microsyst Nanoeng ; 9: 40, 2023.
Article in English | MEDLINE | ID: mdl-37007604

ABSTRACT

Plasmonic lithography, which uses the evanescent electromagnetic (EM) fields to generate image beyond the diffraction limit, has been successfully demonstrated as an alternative lithographic technology for creating sub-10 nm patterns. However, the obtained photoresist pattern contour in general exhibits a very poor fidelity due to the near-field optical proximity effect (OPE), which is far below the minimum requirement for nanofabrication. Understanding the near-field OPE formation mechanism is important to minimize its impact on nanodevice fabrication and improve its lithographic performance. In this work, a point-spread function (PSF) generated by a plasmonic bowtie-shaped nanoaperture (BNA) is employed to quantify the photon-beam deposited energy in the near-field patterning process. The achievable resolution of plasmonic lithography has successfully been enhanced to approximately 4 nm with numerical simulations. A field enhancement factor (F) as a function of gap size is defined to quantitatively evaluate the strong near-field enhancement effect excited by a plasmonic BNA, which also reveals that the high enhancement of the evanescent field is due to the strong resonant coupling between the plasmonic waveguide and the surface plasmon waves (SPWs). However, based on an investigation of the physical origin of the near-field OPE, and the theoretical calculations and simulation results indicate that the evanescent-field-induced rapid loss of high-k information is one of the main optical contributors to the near-field OPE. Furthermore, an analytic formula is introduced to quantitatively analyze the effect of the rapidly decaying feature of the evanescent field on the final exposure pattern profile. Notably, a fast and effective optimization method based on the compensation principle of the exposure dose is proposed to reduce the pattern distortion by modulating the exposure map with dose leveling. The proposed pattern quality enhancement method can open new possibilities in the manufacture of nanostructures with ultrahigh pattern quality via plasmonic lithography, which would find potentially promising applications in high density optical storage, biosensors, and plasmonic nanofocusing.

3.
ACS Omega ; 7(50): 46051-46065, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36570294

ABSTRACT

A thorough understanding of the control mechanisms of coal reservoir modification on methane adsorption and desorption is essential as this is a key technique for increasing the effectiveness of gas extraction. In this study, molecular dynamics simulations and neural networks were used to evaluate the effects of several coal reservoir alteration factors on gas desorption, from both microscopic and macroscopic perspectives. The findings demonstrated a direct correlation between coal pore size and the amount of methane adsorbed, as well as an inverse relationship between coal pore size and methane adsorption capacity and energy. The different methane-repelling properties of CO2, N2, and H2O, which are frequently used in coal reservoir reforming, are primarily due to the different diffusion capabilities of these three gases. The best reservoir reforming effect can be obtained by setting the pressure ratio of CO2 to N2 to 3.4:6.6. The thickness, depth, gas content, height, advance speed, rate of extraction, and daily production of coal are all closely interrelated, enabling a more accurate assessment of gas gushing.

4.
IEEE Trans Neural Netw Learn Syst ; 33(12): 7223-7236, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34111004

ABSTRACT

Image smoothing is a prerequisite for many computer vision and graphics applications. In this article, we raise an intriguing question whether a dataset that semantically describes meaningful structures and unimportant details can facilitate a deep learning model to smooth complex natural images. To answer it, we generate ground-truth labels from easy samples by candidate generation and a screening test and synthesize hard samples in structure-preserving smoothing by blending intricate and multifarious details with the labels. To take full advantage of this dataset, we present a joint edge detection and structure-preserving image smoothing neural network (JESS-Net). Moreover, we propose the distinctive total variation loss as prior knowledge to narrow the gap between synthetic and real data. Experiments on different datasets and real images show clear improvements of our method over the state of the arts in terms of both the image cleanness and structure-preserving ability. Code and dataset are available at https://github.com/YidFeng/Easy2Hard.

5.
Chin Med J (Engl) ; 134(22): 2700-2709, 2021 Nov 03.
Article in English | MEDLINE | ID: mdl-34732663

ABSTRACT

BACKGROUND: There is limited information about thymosin α1 (Tα1) as adjuvant immunomodulatory therapy, either used alone or combined with other treatments, in patients with non-small cell lung cancer (NSCLC). This study aimed to evaluate the effect of adjuvant Tα1 treatment on long-term survival in margin-free (R0)-resected stage IA-IIIA NSCLC patients. METHODS: A total of 5746 patients with pathologic stage IA-IIIA NSCLC who underwent R0 resection were included. The patients were divided into the Tα1 group and the control group according to whether they received Tα1 or not. A propensity score matching (PSM) analysis was performed to reduce bias, resulting in 1027 pairs of patients. RESULTS: After PSM, the baseline clinicopathological characteristics were similar between the two groups. The 5-year disease-free survival (DFS) and overall survival (OS) rates were significantly higher in the Tα1 group compared with the control group. The multivariable analysis showed that Tα1 treatment was independently associated with an improved prognosis. A longer duration of Tα1 treatment was associated with improved OS and DFS. The subgroup analyses showed that Tα1 therapy could improve the DFS and/or OS in all subgroups of age, sex, Charlson Comorbidity Index (CCI), smoking status, and pathological tumor-node-metastasis (TNM) stage, especially for patients with non-squamous cell NSCLC and without targeted therapy. CONCLUSION: Tα1 as adjuvant immunomodulatory therapy can significantly improve DFS and OS in patients with NSCLC after R0 resection, except for patients with squamous cell carcinoma and those receiving targeted therapy. The duration of Tα1 treatment is recommended to be >24 months.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/surgery , Chemotherapy, Adjuvant , Humans , Immunomodulation , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Lung Neoplasms/surgery , Neoplasm Staging , Propensity Score , Retrospective Studies , Thymalfasin
6.
Org Lett ; 23(11): 4158-4162, 2021 06 04.
Article in English | MEDLINE | ID: mdl-34013731

ABSTRACT

Two rearranged triterpenoids, representing new subtypes of pentacyclic triterpenoids, with unique 6/6/6/7/5 and 6/6/5/6/6/6 ring systems were isolated from Alstonia scholaris. Their structures were established by spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Both compounds exhibited potent antihyperuricemic bioactivity in vitro and in vivo.


Subject(s)
Alstonia/chemistry , Gout Suppressants/pharmacology , Triterpenes/pharmacology , Crystallography, X-Ray , Gout Suppressants/analysis , Gout Suppressants/chemistry , Plant Leaves/chemistry , Triterpenes/chemistry , Triterpenes/isolation & purification
7.
Chem Biodivers ; 18(3): e2000964, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33533151

ABSTRACT

Endophytic fungi play important roles for host's stress tolerance including invasion by pathogenic microbes. Small molecules are common weapons in the microbe-microbe interactions. Panax notoginseng is a widely used traditional Chinese medicinal plant and harbors many endophytes, some exert functions against pathogens. Here, we report six new compounds named myrothins A-F (1-6) produced by Myrothecium sp. BS-31, an endophyte isolated from P. notoginseng, and their antifungal activities against pathogenic fungi causing host root-rot disease. Their structures were elucidated with analysis of spectroscopic data including 1D and 2D NMR, HR-ESI-MS. Myrothins B (2) and E (5) showed the weak activity against Fusarium oxysporum and Phoma herbarum, and myrothins F (6) showed weak activity against F. oxysporum.


Subject(s)
Antifungal Agents/pharmacology , Endophytes/chemistry , Hypocreales/chemistry , Panax notoginseng/microbiology , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Dose-Response Relationship, Drug , Fusarium/drug effects , Microbial Sensitivity Tests , Molecular Structure , Phoma/drug effects , Stereoisomerism , Structure-Activity Relationship
8.
Front Physiol ; 11: 788, 2020.
Article in English | MEDLINE | ID: mdl-32792971

ABSTRACT

Free radicals and oxidative stress play an important role in the pathogenesis of noise-induced hearing loss (NIHL). Some ginseng monomers showed certain therapeutic effects in NIHL by scavenging free radicals. Therefore, we hypothesized that ginsenoside Rd (GSRd) may exert neuroprotective effects after noise-induced auditory system damage through a mechanism involving the SIRT1/PGC-1α signaling pathway. Forty-eight guinea pigs were randomly divided into four equal groups (normal control group, noise group, experimental group that received GSRd dissolved in glycerin through an intraperitoneal injection at a dose of 30 mg/kg body weight from 5 days before noise exposure until the end of the noise exposure period, and experimental control group). Hearing levels were examined by auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE). Hematoxylin-eosin and Nissl staining were used to examine neuron morphology. RT-qPCR and western blotting analysis were used to examine SIRT1/PGC-1α signaling and apoptosis-related genes, including Bax and Bcl-2, in the auditory cortex. Bax and Bcl-2 expression was assessed via immunohistochemistry analysis. Superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) levels were determined using a commercial testing kit. Noise exposure was found to up-regulate ABR threshold and down-regulate DPOAE amplitudes, with prominent morphologic changes and apoptosis of the auditory cortex neurons (p < 0.01). GSRd treatment restored hearing loss and remarkably alleviated morphological changes or apoptosis (p < 0.01), concomitantly increasing Bcl-2 expression and decreasing Bax expression (p < 0.05). Moreover, GSRd increased SOD and GSH-Px levels and decreased MDA levels, which alleviated oxidative stress damage and activated SIRT1/PGC-1α signaling pathway. Taken together, our findings suggest that GSRd ameliorates auditory cortex injury associated with military aviation NIHL by activating the SIRT1/PGC-1α signaling pathway, which can be an attractive pharmacological target for the development of novel drugs for NIHL treatment.

9.
Int J Syst Evol Microbiol ; 69(2): 567-571, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30605074

ABSTRACT

A novel Gram-positive bacterium, designated strain YIM PH21725T, was isolated from a sample of rhizospheric soil of Panaxnotoginseng cultivated in Anning, Yunnan. The strain contained meso-diaminopimelic acid in the cell-wall peptidoglycan. The main fatty acids identified were C17 : 0, iso-C15 : 0, iso-C16 : 0 and C16 : 0. The main menaquinone was MK-9 (H4). The polar lipids included phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, phospholipids and phospholipids of an unidentified structure containing glucosamine. The G+C content of genomic DNA was 69.43 mol%. On the basis of its 16S rRNA gene sequence, strain YIM PH21725T should belong to the genus Amycolatopsis, and was closely related to Amycolatopsis sulphurea DSM 46092T (98.57 %), Amycolatopsis jejuensis JCM13280T (97.27 %), Amycolatopsis jiangsuensis KCTC 19885T (96.88 %) and Amycolatopsis ultiminotia JCM 16989T (96.8 %). The phenotypic, chemotaxonomic, phylogenetic and digital DNA-DNA hybridization results clearly indicated that strain YIM PH21725T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsispanacis sp. nov. is proposed. The type strain is YIM PH21725T (=CCTCC AA 2017044T=KCTC 49031T=DSM 105902T).


Subject(s)
Actinobacteria/classification , Panax notoginseng/microbiology , Phylogeny , Soil Microbiology , Actinobacteria/isolation & purification , Bacterial Typing Techniques , Base Composition , Cell Wall/chemistry , China , DNA, Bacterial/genetics , Diaminopimelic Acid/chemistry , Fatty Acids/chemistry , Nucleic Acid Hybridization , Peptidoglycan/chemistry , Phospholipids/chemistry , RNA, Ribosomal, 16S/genetics , Rhizosphere , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry
10.
Sci Rep ; 5: 16760, 2015 Nov 13.
Article in English | MEDLINE | ID: mdl-26565726

ABSTRACT

The adoptive transfer of the natural regulatory B cells and macrophages should be a useful treatment for inflammation and autoimmune disease. However, it is usually difficult to isolate these cells from the tissues and expand them. Here, we investigated the feasibility of adoptively transferring peritoneal cells (PCs) as a treatment for DSS-induced colitis. We found that peritoneal cavity can provide an easily accessible site for harvesting enough number of PCs, namely, two-dose PCs for the treatment from a mouse in one operation. Adoptive therapy of these cells from healthy mice or those with disease is effectively in reducing the disease activity score. The natural B cells and macrophages of the infused PCs can selectively migrate to lesion sites and regulate the expression of Stat3, NF-κB, Smad3 and Smad7. Additionally, PCs exert dual activity of IL-10 and TGF-ß secreted spontaneously by both peritoneal B cells and macrophages, which in turn enhance the induction of regulatory B cells and Macrophages in microenvironment of inflammation. Moreover, PCs can re-establish immunological tolerance in the OVA-immunized mice. Thus, our findings provide a new strategy for colitis therapy and could be of importance in additional exploration of other inflammation and autoimmune diseases therapy.


Subject(s)
Colitis/immunology , Colitis/therapy , Dextran Sulfate/administration & dosage , Intestinal Mucosa/immunology , Adoptive Transfer/methods , Animals , B-Lymphocytes/immunology , Colitis/chemically induced , Disease Models, Animal , Female , Inflammation/immunology , Inflammation/therapy , Interleukin-10/immunology , Macrophages/immunology , Mice , Mice, Inbred C57BL , NF-kappa B/immunology , Signal Transduction/immunology , Smad Proteins, Receptor-Regulated/metabolism , Transforming Growth Factor beta/immunology
11.
J Diabetes Complications ; 29(5): 724-30, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25890843

ABSTRACT

AIM: To derive a more precise estimation of carotid intima-media thickness (CIMT) levels in patients with type 1 diabetes mellitus (T1DM) by meta-analysis. METHODS: PubMed and Embase databases were searched to identify all available studies comparing CIMT levels between T1DM group and control group. Meta-analysis was performed to compare the difference of overall mean CIMT levels between the two groups. Publication bias was evaluated by funnel plot, Begg' test and Egger' test. Meta-regression analysis was conducted to investigate the influential factors on CIMT difference. The meta-analysis was conducted by STATA 12.0 software. RESULTS: A total of 1840 articles were obtained after searching databases; 47 studies were finally included in the meta-analysis. Significant heterogeneity was observed among these studies (Q = 768.75, P < 0.001, I(2) = 94.0%). Compared with the control group, the T1DM group had significantly higher CIMT levels (standardized mean difference: 1.01, 95% CI: 0.75-1.28; P < 0.001). A likely source of heterogeneity was Newcastle-Ottawa Scale (NOS) scores and sample size ratio of patents and controls. The funnel plot did not show a skewed or asymmetrical shape, and the result of Begg' test and Egger' test was P = 0.178 and P = 0.145 respectively. Accordingly, it could be assumed that publication bias was not present. CONCLUSION: T1DM patients have significantly increased CIMT levels compared to control subjects.


Subject(s)
Atherosclerosis/complications , Diabetes Mellitus, Type 1/complications , Diabetic Angiopathies/diagnostic imaging , Evidence-Based Medicine , Atherosclerosis/diagnostic imaging , Biomarkers , Carotid Intima-Media Thickness , Humans
12.
Inflammation ; 37(6): 2067-75, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24906564

ABSTRACT

Premature atherosclerosis, the hallmark of cardiovascular diseases, has been found to be a significant cause of late deaths in systemic lupus erythematosus (SLE) patients. Therefore, early identification of atherosclerosis before the overt disease is curial for the management program of SLE. Flow-mediated dilatation (FMD%) is a reliable, noninvasive, easy to use, reproducible, and pathogenically relevant index for early atherosclerosis. In recent years, a number of studies have been performed to compare the mean FMD% difference between patients with SLE and healthy controls. However, these studies have shown inconclusive or even contradictory findings. In this study, to derive a more precise comparison of FMD% difference between SLE patients and healthy controls, a meta-analysis was performed. Databases were searched to identify all available studies comparing FMD% between SLE patients and healthy controls. The study eligibility criteria were cohort or case-control studies with data on both patients diagnosed with SLE and healthy controls, and use of high-resolution ultrasonography to detect FMD. Random effect meta-analysis was conducted to evaluate the overall mean FMD% difference between the two groups. Publication bias was detected by funnel plot and Egger's test. Meta-regression analysis was performed to investigate the potential influencing factors on FMD% difference. Of the 434 articles initially identified, 22 were finally included in the meta-analysis. Compared to healthy controls, SLE patients had significantly lower FMD% (standardized mean difference, -1.19; 95% CI, -1.63, -0.74; P < 0.001). There was significant heterogeneity among these studies (I (2) = 94.3%, P < 0.001), which was mainly due to variations in disease duration of SLE patients. The funnel plot showed a skewed shape, indicating a marked publication bias, which was further supported by the Egger's test (P = 0.006). However, after the correction for potential publication bias by using the trim-and-fill method, the main results for all studies combined were still significant (P < 0.001). Taken together, these findings support the current evidence on a higher cardiovascular burden in SLE and support using FMD% as a surrogate for premature atherosclerosis in SLE patients.


Subject(s)
Blood Flow Velocity , Lupus Erythematosus, Systemic/diagnosis , Lupus Erythematosus, Systemic/physiopathology , Vasodilation , Atherosclerosis/diagnosis , Atherosclerosis/epidemiology , Atherosclerosis/physiopathology , Blood Flow Velocity/physiology , Case-Control Studies , Cohort Studies , Humans , Lupus Erythematosus, Systemic/epidemiology , Vasodilation/physiology
13.
Transgenic Res ; 22(6): 1133-42, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23740205

ABSTRACT

Maize (Zea mays spp. mays) is a staple crop for more than 900 million people. The seeds or kernels provide a rich source of calories because ~70% of the weight is carbohydrate, mostly in the form of starch. The content and composition of starch are complex traits controlled by many genes, offering multiple potential targets for intervention. We used a multigene engineering approach combining the overexpression of Bt2, Sh2, Sh1 and GbssIIa (to enhance the activity of sucrose synthase, AGPase and granule-bound starch synthase) with the suppression of SbeI and SbeIIb by RNA interference (to reduce the activity of starch branching enzyme). Maize plants expressing all six genes plus the selectable marker showed a 2.8-7.7% increase in the endosperm starch content and a 37.8-43.7% increase in the proportion of amylose, which was significant compared to untransformed control plants. We also observed improvements in other agronomic traits, such as a 20.1-34.7% increase in 100-grain weight, a 13.9-19.0% increase in ear weight, and larger kernels with a better appearance, presumably reflecting the modified starch structure within the kernels. Our results confirm that multigene engineering applied to the starch biosynthesis pathway can not only modulate the quality and quantity of starch but can also improve starch-dependent agronomic traits.


Subject(s)
Amylose/genetics , Endosperm/genetics , Starch/biosynthesis , Zea mays/genetics , 1,4-alpha-Glucan Branching Enzyme/biosynthesis , 1,4-alpha-Glucan Branching Enzyme/genetics , Amylose/chemistry , Endosperm/chemistry , Endosperm/growth & development , Gene Expression Regulation, Plant , Genetic Engineering , Glucosyltransferases/biosynthesis , Plant Proteins/genetics , RNA Interference , Starch/chemistry , Starch Synthase/biosynthesis , Starch Synthase/genetics , Sucrose/metabolism , Zea mays/chemistry
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