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Unveiling the role of hypoxia-inducible factor 2alpha in osteoporosis:Implications for bone health
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作者 ling-ling wang Zhan-Jin Lu +3 位作者 Shun-Kui Luo Yun Li Zhe Yang Hong-Yun Lu 《World Journal of Stem Cells》 SCIE 2024年第4期389-409,共21页
BACKGROUND Osteoporosis(OP)has become a major public health problem worldwide.Most OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing ... BACKGROUND Osteoporosis(OP)has become a major public health problem worldwide.Most OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing osteogenesis.In the bone marrow(BM)niche,bone mesenchymal stem cells(BMSCs)are exposed to a hypoxic environment.Recently,a few studies have demonstrated that hypoxiainducible factor 2alpha(HIF-2α)is involved in BMSC osteogenic differentiation,but the molecular mechanism involved has not been determined.AIM To investigate the effect of HIF-2αon the osteogenic and adipogenic differentiation of BMSCs and the hematopoietic function of hematopoietic stem cells(HSCs)in the BM niche on the progression of OP.METHODS Mice with BMSC-specific HIF-2αknockout(Prx1-Cre;Hif-2αfl/fl mice)were used for in vivo experiments.Bone quantification was performed on mice of two genotypes with three interventions:Bilateral ovariectomy,semilethal irradiation,and dexamethasone treatment.Moreover,the hematopoietic function of HSCs in the BM niche was compared between the two mouse genotypes.In vitro,the HIF-2αagonist roxadustat and the HIF-2αinhibitor PT2399 were used to investigate the function of HIF-2αin BMSC osteogenic and adipogenic differentiation.Finally,we investigated the effect of HIF-2αon BMSCs via treatment with the mechanistic target of rapamycin(mTOR)agonist MHY1485 and the mTOR inhibitor rapamycin.RESULTS The quantitative index determined by microcomputed tomography indicated that the femoral bone density of Prx1-Cre;Hif-2αfl/fl mice was lower than that of Hif-2αfl/fl mice under the three intervention conditions.In vitro,Hif-2αfl/fl mouse BMSCs were cultured and treated with the HIF-2αagonist roxadustat,and after 7 d of BMSC adipogenic differentiation,the oil red O staining intensity and mRNA expression levels of adipogenesis-related genes in BMSCs treated with roxadustat were decreased;in addition,after 14 d of osteogenic differentiation,BMSCs treated with roxadustat exhibited increased expression of osteogenesis-related genes.The opposite effects were shown for mouse BMSCs treated with the HIF-2αinhibitor PT2399.The mTOR inhibitor rapamycin was used to confirm that HIF-2αregulated BMSC osteogenic and adipogenic differentiation by inhibiting the mTOR pathway.Consequently,there was no significant difference in the hematopoietic function of HSCs between Prx1-Cre;Hif-2αfl/fl and Hif-2αfl/fl mice.CONCLUSION Our study showed that inhibition of HIF-2αdecreases bone mass by inhibiting the osteogenic differentiation and increasing the adipogenic differentiation of BMSCs through inhibition of mTOR signaling in the BM niche. 展开更多
关键词 Hypoxia-inducible factor-2α Bone marrow niche Bone mesenchymal stem cells OSTEOPOROSIS Osteogenic/adipogenic differentiation Mechanistic target of rapamycin signaling pathway
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Efficacy of surgical resection and ultra-reduced tension suture combined with superficial radiation in keloid treatment
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作者 Xiao-Ying Hu Qiao Yang +4 位作者 Xiao-Yu Guan Jin-Ying Li ling-ling wang Kun Li Xiao-Tao Zhang 《World Journal of Clinical Cases》 SCIE 2023年第35期8310-8319,共10页
BACKGROUND There are many available treatment options for keloid;however,single treatments are usually less effective.Therefore,more scientifically rational and effective com-bined treatment methods should be sought t... BACKGROUND There are many available treatment options for keloid;however,single treatments are usually less effective.Therefore,more scientifically rational and effective com-bined treatment methods should be sought to solve the pain associated with keloids.AIM To explore the efficacy and safety of surgical resection and ultra-reduced tension suture combined with superficial radiation as keloid treatment.METHODS Fifteen keloid patients admitted to Qingdao Eighth People's Hospital from June 2020 to January 2022 were enrolled in this retrospective analysis.All patients underwent a comprehensive treatment approach comprising surgical resection,ultra-reduced tension suture incision,and superficial radiation therapy within 24 h postoperatively.The modified Vancouver Scar Scale(mVSS)and Patient and Observer Scar Assessment Scale(POSAS)were used to evaluate the treatment effect,whereas the efficacy,adverse effects,and recurrence rate were observed according to the 12-mo follow-up after treatment.RESULTS The mVSS and POSAS scores at 1 and 6 mo after combination treatment decreased compared to before treatment(P<0.001),and the overall response rate was 93.3%.Only one case recurred,yielding a 6.7%recurrence rate.The incidence of local chromour sedimentation rate in 1–3 mo after radiotherapy was 33.3%(5 patients),all subsiding after 6–9 mo,without complications,such as delayed wound healing or dermatitis.CONCLUSION Surgical resection,super subtraction sutures,and superficial radiotherapy are treatment methods with short courses,low recurrence rates,and good safety profiles. 展开更多
关键词 KELOID Ultrasound suture Radiotherapeutics Superficial radiation Ultra-reduced tension suture RADIATION
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Eutrophication model for river-type reservoir tributaries and its applications 被引量:9
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作者 ling-ling wang Zhen-zhen YU +1 位作者 Hui-chao DAI Qing-hua CAI 《Water Science and Engineering》 EI CAS 2009年第1期16-24,共9页
With the impoundment of the Three Gorges Reservoir, algal blooms have been found in some tributaries. In this study, according to the theoretical analysis of the eutrophication mechanism in a river-type reservoir trib... With the impoundment of the Three Gorges Reservoir, algal blooms have been found in some tributaries. In this study, according to the theoretical analysis of the eutrophication mechanism in a river-type reservoir tributary, a one-dimensional eutrophication model was developed for the Xiangxi River tributary of the Three Gorges Reservoir, and the influence of hydrodynamic conditions on the primary growth rate of algae was investigated. Furthermore, numerical predictions of hydraulic variables and eutrophication factors, such as the concentration distribution of TP, TN, and Chl-a in the spatial and temporal domains, were carried out. Comparison of computation results of TP, TN, and Chl-a concentrations along the river in the spring of 2005 with experimental data demonstrates the validity of the model. The agreement between the computation results and the experimental data of TP and TN concentrations is better than the agreement between those of Chl-a concentration. The simulated results also show that the Chl-a concentration downstream is much higher than that in the upstream tributary, which potentially indicates the outbreak of algae in this area. Therefore, this study provides a feasible method of accurately predicting the state of eutrophication in river-type reservoirs and their tributaries. 展开更多
关键词 eutrophication model river-type reservoir Xiangxi River tributary algal blooms
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Clonality analysis of neuroendocrine cells in gastric adenocarcinoma 被引量:5
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作者 ling-ling wang Gen-You Yao +2 位作者 Zhong-Sheng Zhao Xiao-Li Wei Ru-Jun Xu 《World Journal of Gastroenterology》 SCIE CAS 2013年第32期5340-5346,共7页
AIM:To achieve a better understanding of the origination of neuroendocrine(NE)cells in gastric adenocarcinoma.METHODS:In this study,120 cases of gastric adenocarcinoma were obtained.First,frozen section-immunohistoche... AIM:To achieve a better understanding of the origination of neuroendocrine(NE)cells in gastric adenocarcinoma.METHODS:In this study,120 cases of gastric adenocarcinoma were obtained.First,frozen section-immunohistochemistrical samples were selected from a large quantity of neuroendocrine cells.Second,laser capture microdissection was used to get target cells from gastric adenocarcinoma and whole genome amplification was applied to get a large quantity of DNA for further study.Third,genome-wide microsatellite abnormalities[microsatellite instability(MSI),loss of heterozygosity (LOH)]and p53 mutation were detected by polymerase chain reaction(PCR)-single-strand conformation polymer-phism-silver staining and PCR-sequencing in order to identify the clonality of NE cells.RESULTS:The total incidence rate of MSI was 27.4%,while LOH was 17.9%.Ten cases had a highest concordance for the two types of cells.The other samples had similar microsatellite changes,except for cases 7 and10.Concordant p53 mutations exhibited in sample 4,14,21 and 27,and there were different mutations between two kinds of cells in case 7.In case 17,mutation took place only in adenocarcinoma cells.p53 mutation was closely related with degree of differentiation,tumor-node-metastasis stage,vessel invasion and lymph node metastasis.In brief,NE and adenocarcinoma cells showed the same MSI,LOH or p53 mutation in most cases(27/30).In the other three cases,different MSI,LOH or p53 mutation occurred.CONCLUSION:NE and the gastric adenocarcinoma cells may mainly derive from the same stem cells,but the remaining cases showing different origin needs further investigation. 展开更多
关键词 NEUROENDOCRINE DIFFERENTIATION CLONAL analysis GASTRIC ADENOCARCINOMA NEUROENDOCRINE CELLS
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Malignant glomus tumor of the intestinal ileum with multiorgan metastases:A case report and review of literature 被引量:6
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作者 Jian-Hong Chen Lin Lin +6 位作者 Kui-Liang Liu Hui Su ling-ling wang Peng-Peng Ding Quan Zhou Hong Liu Jing Wu 《World Journal of Gastroenterology》 SCIE CAS 2020年第7期770-776,共7页
BACKGROUND Glomus tumors(GTs)are rare mesenchymal neoplastic lesions derived from cells of the glomus body.GTs rarely occurs in the visceral organs,where there may be few or no glomus bodies,and the majority of GTs ar... BACKGROUND Glomus tumors(GTs)are rare mesenchymal neoplastic lesions derived from cells of the glomus body.GTs rarely occurs in the visceral organs,where there may be few or no glomus bodies,and the majority of GTs are benign,rarely demonstrating aggressive or malignant behavior and histological features.CASE SUMMARY We report a patient with malignant GTs of the intestinal ileum with multiorgan metastases who was admitted due to moderate anemia.Capsule endoscopy revealed a bleeding mass in the intestinal ileum,and the patient underwent segmental ileal resection through laparoscopic surgery.The histopathological and immunohistochemical diagnoses were consistent with malignant GT.Longterm follow-up showed that the GT had metastasized to multiple organs such as the colon,brain,and possibly the lung.CONCLUSION This case was characterized by the highest degree of malignancy and by multiorgan metastases,and it was the first case of intestinal GT uncovered by capsule endoscopy. 展开更多
关键词 Malignant glomus tumor INTESTINE METASTASES Capsule endoscopy Diagnosis Case report
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Large eddy simulation of vertical turbulent jets under JONSWAP waves 被引量:2
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作者 Jun Lu ling-ling wang +1 位作者 Hong-Wu Tang Hui-Chao Dai 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第2期189-199,共11页
The effect of random waves on vertical plane turbulent jets is studied numerically and the mechanism behind the interaction of the jet and waves is analyzed. The large eddy simulation method is used and the σ-coordin... The effect of random waves on vertical plane turbulent jets is studied numerically and the mechanism behind the interaction of the jet and waves is analyzed. The large eddy simulation method is used and the σ-coordinate system is adopted. Turbulence is modeled by a dynamic coherent eddy model. The σ-coordinate transformation is introduced to map the irregular physical domain with a wavy free surface and an uneven bottom onto a regular computational domain. The fractional step method is used to solve the filtered Navier–Stokes equations. Results presented include the distribution of velocity, the decay law of the mean velocity along the jet axis, self-similar characteristics and volume flux per unit width. In particular, the role of coherent structures on the momentum transfer along the jet centerline and the jet instantaneous characteristics in JONSWAP waves are a special focus of this research. The numerical results obtained are of great theoretical importance in understanding the behavior of turbulent jets in random wave environments. 展开更多
关键词 Large eddy simulation Dynamic coherent eddy model Σ-COORDINATE Turbulent jet JONSWAP wave
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Noninvasive evaluation of hepatic fibrosis in children with infant hepatitis syndrome 被引量:2
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作者 Zhi-Xian Li Yun He +5 位作者 Ji Wu Bu-Lin Zhang Hong Yang ling-ling wang Yun Ma Kang-Lai Wei 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第44期7155-7160,共6页
AIM: To elucidate the impact of hemodynamic parameters on ultrasonography and serum fibrosis markers for the assessment of liver fibrosis in the children with infant hepatitis syndrome (IHS). METHODS: Forty-one ch... AIM: To elucidate the impact of hemodynamic parameters on ultrasonography and serum fibrosis markers for the assessment of liver fibrosis in the children with infant hepatitis syndrome (IHS). METHODS: Forty-one children with IHS and 46 healthy infants were examined by ultrasonography, and several hemodynamic indices such as peak systolic velocity (PSV) and resistant index (RI) of proper hepatic artery (PHA) were measured. Serum fibrosis markers including hyaluronic acid (HA), pre-collagen type-Ⅲ (PC-Ⅲ), collagen type Ⅳ (C-Ⅳ), and laminin (LN) were assayed by radioimmunoassays. In children with IHS, liver tissues were obtained either by ultrasound-guided liver biopsy (n = 35) or in the course of operation (n = 6). The stages of hepatic fibrosis were scored as mild (S1 and S2), moderate (S3), or severe (S4) according to liver histological diagnosis. Multiple groups comparative and Spearman correlative analyses were carried out. RESULTS: Histopathologically, 39 children (95.1%) were found to have hepatic fibrosis, 12 of them stage Sl or S2, 12 stage S3, and 15 stage S4. PSV, RI of the PHA, and serum HA showed a consecutive increase from mild to severe hepatic fibrosis and a close positive correlation with hepatic fibrosis in IHS group (r = 0.717, 0.745 and 0.712, respectively, P = 0.001). The Doppler waveform of HV was also positively correlated with the degree of hepatic fibrosis in IHS group (r = 0.783, P 〈 0.001).CONCLUSION: Combination of ultrasonic studies on the hepatic hemodynamics with the evaluation of serum HA may provide an indicator for hepatic fibrosis in patients with IHS, This may be a useful noninvasive method for the diagnosis and evaluation of the prognosis of IHS. 展开更多
关键词 Infant hepatitis syndrome Hepatic fibrosis Doppler ultrasonography HEMODYNAMICS Hyaluronic acid
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Liquid-phase epoxidation of propylene with molecular oxygen by chloride manganese meso-tetraphenylporphyrins 被引量:1
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作者 Xian-Tai Zhou ling-ling wang +1 位作者 Yang Li Hong-Bing Ji 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第8期61-65,共5页
Propylene molecule owns two active sites,the direct epoxidation of propylene by dioxygen is still a challenge due to the limitation of selectivity.In this work,the direct liquid-phase propylene aerobic epoxidation pro... Propylene molecule owns two active sites,the direct epoxidation of propylene by dioxygen is still a challenge due to the limitation of selectivity.In this work,the direct liquid-phase propylene aerobic epoxidation protocol by chloride manganese meso-tetraphenylporphyrin(MnTPPCl)was developed.The conversion of propylene was 12.7%,and the selectivity towards PO(propylene oxide)reached up to 80.5%.The formation of PO was attributed to the mechanism via high-valent Mn species,which was confirmed by means of in situ UV–vis spectrum. 展开更多
关键词 PROPYLENE EPOXIDATION DIOXYGEN Manganese porphyrins Liquid phase
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Elevated serum growth differentiation factor 15 in multiple system atrophy patients:A case control study 被引量:1
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作者 Tao Yue Hui Lu +4 位作者 Xiao-Mei Yao Xia Du ling-ling wang Dan-Dan Guo Yi-Ming Liu 《World Journal of Clinical Cases》 SCIE 2020年第12期2473-2483,共11页
BACKGROUND Multiple system atrophy(MSA) is a serious progressive neurodegenerative disease. Early diagnosis of MSA is very difficult, and diagnostic biomarkers are limited. Growth differentiation factor 15(GDF15) is i... BACKGROUND Multiple system atrophy(MSA) is a serious progressive neurodegenerative disease. Early diagnosis of MSA is very difficult, and diagnostic biomarkers are limited. Growth differentiation factor 15(GDF15) is involved in the differentiation and progression of the central nervous system, and is widely distributed in peripheral blood, which may be a novel biomarker for MSA.AIM To determine serum GDF15 levels, related factors and their potential diagnostic value in MSA patients, compared with Parkinson’s disease(PD) patients and healthy controls.METHODS A case-control study was conducted, including 49 MSA patients, 50 PD patients and 50 healthy controls. Serum GDF15 levels were measured by human enzymelinked immunosorbent assay, and the differences between the MSA, PD and control groups were analyzed. Further investigations were performed in different MSA subgroups according to age of onset, sex, clinical subtypes, diagnostic criteria, and disease duration. Receiver-operating characteristic curve analysiswas used to evaluate the diagnostic value of GDF15, especially for the differential diagnosis between MSA and PD.RESULTS Serum GDF15 levels were significantly higher in MSA patients than in PD patients and healthy controls(P = 0.000). Males and those with a disease duration of more than three years showed higher serum GDF15 levels(P = 0.043 and 0.000;respectively). Serum GDF15 levels may be a potential diagnostic biomarker for MSA patients compared with healthy controls and PD patients(cutoff: 470.42 pg/m L, sensitivity: 85.7%, specificity: 88.0%;cutoff: 1075.91 pg/m L, sensitivity:51.0%, specificity: 96.0%;respectively).CONCLUSION Serum GDF15 levels are significantly higher in MSA patients and provide suggestions on the etiology of MSA. 展开更多
关键词 Multiple system atrophy Parkinson’s disease Serum growth differentiation factor 15 BIOMARKER Receiver-operating characteristic curve Neurodegenerative disease
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Facile Fabrication of Platinum Nanoparticles Supported on Nitrogen-doped Carbon Nanotubes and Their Catalytic Activity
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作者 ling-ling wang Long Shen +2 位作者 Hai-ying Jin Lu-ping Zhu Li-jun wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期327-331,共5页
A facile impregnation method under mild condition is designed for synthesis of highly dispersed Pt nanoparticles with a narrow size of 4-7 nm on nitrogen-doped carbon nanotubes (CNx). CNx do not need any pre-surface... A facile impregnation method under mild condition is designed for synthesis of highly dispersed Pt nanoparticles with a narrow size of 4-7 nm on nitrogen-doped carbon nanotubes (CNx). CNx do not need any pre-surface modification due to the inherent chemical activity. The structure and nature of Pt/CNx were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive spectroscopy spectrum. All the experimental results revealed that the large amount of doped nitrogen atoms in CNx was virtually effective for capturing the Pt(IV) ions. The improved surface nitrogen functionalities and hydrophilicity contributed to the good dispersion and immobi- lization of Pt nanoparticles on the CNx surface. The Pt/CNx served as active and reusable catalysts in the hydrogenation of allyl alcohol. This could be attributed to high dispersion of Pt nanoparticles and stronger interaction between Pt and the supports, which prevented the Pt nanoparticles from aggregating into less active Pt black and from leaching as well. 展开更多
关键词 Carbon nanotube Nitrogen doping Allyl alcohol hydrogenation Pt nanoparticles Heterogeneous catalyst
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Impact of depth ratio on flow structure and turbulence characteristics of compound open channel flows
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作者 Shao-wei Ding Cheng Zeng +2 位作者 Jie Zhou ling-ling wang Chen Chen 《Water Science and Engineering》 EI CAS CSCD 2022年第3期265-272,共8页
Compound open channel flows appear in most natural rivers are of great importance in river management and flood control.In this study,large eddy simulations were carried out to simulate the compound open channel flows... Compound open channel flows appear in most natural rivers are of great importance in river management and flood control.In this study,large eddy simulations were carried out to simulate the compound open channel flows with four different depth ratios(hr=0.10,0.25,0.50,and 0.75).The main flow velocity,secondary flow,Reynolds stress,and bed shear stress were obtained from numerical simulations.The depth-averaged stream wise momentum equation was used to quantify the lateral momentum exchange between the main channel and floodplain.The instantaneous coherent structures were presented by the Q criterion method.The impact of hr on flow structure and turbulence charac-teristics was analyzed.The results showed that with the increase of hr,the high velocity area in the main channel shifted to the floodplain,and the dip phenomenon became more obvious;the Reynolds stress largely contributed to the lateral momentum exchange within the flows near the side walls of floodplain;and the vortex structures were found to significantly increase in the floodplain region. 展开更多
关键词 Large eddy simulation Compound open channel Depth ratio Flow structure Turbulence characteristics
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Recognition of Film Type Using HSV Features on Deep-Learning Neural Networks
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作者 Ching-Ta Lu Jia-An Lin +3 位作者 Chia-Yi Chang Chia-Hua Liu ling-ling wang Kun-Fu Tseng 《Journal of Electronic Science and Technology》 CAS CSCD 2020年第1期31-41,共11页
The number of films is numerous and the film contents are complex over the Internet and multimedia sources. It is time consuming for a viewer to select a favorite film. This paper presents an automatic recognition sys... The number of films is numerous and the film contents are complex over the Internet and multimedia sources. It is time consuming for a viewer to select a favorite film. This paper presents an automatic recognition system of film types. Initially, a film is firstly sampled as frame sequences. The color space, including hue, saturation,and brightness value(HSV), is analyzed for each sampled frame by computing the deviation and mean of HSV for each film. These features are utilized as inputs to a deep-learning neural network(DNN) for the recognition of film types. One hundred films are utilized to train and validate the model parameters of DNN. In the testing phase, a film is recognized as one of the five categories, including action, comedy, horror thriller, romance, and science fiction, by the trained DNN. The experimental results reveal that the film types can be effectively recognized by the proposed approach, enabling the viewer to select an interesting film accurately and quickly. 展开更多
关键词 Deep-learning FILM TYPE RECOGNITION hue saturation and brightness value(HSV)analysis neural networks video classification
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High-confinement ultra-wideband bandpass filter using compact folded slotline spoof surface plasmon polaritons
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作者 Xue-Wei Zhang Shao-Bin Liu +3 位作者 ling-ling wang Qi-Ming Yu Jian-Lou Shi-Ning Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期255-262,共8页
A novel bandpass filter(BPF)based on spoof surface plasmon polaritons(SSPPs)using a compact folded slotline structure is proposed and experimentally demonstrated.The proposed novel SSPPs structure compared with a conv... A novel bandpass filter(BPF)based on spoof surface plasmon polaritons(SSPPs)using a compact folded slotline structure is proposed and experimentally demonstrated.The proposed novel SSPPs structure compared with a conventional plasmonic waveguide with slot line SSPPs unit structure at the same size,the considerable advantages in much lower asymptotic frequency with tight field confinement,which enable the proposed filter to be more miniaturization.A high-efficient mode conversion structure is designed to transition from TE-mode to SSPPs-mode by gradient slotline lengths.The low-frequency stop-band can be committed with microstrip to slotline evolution on both sides of the dielectric,while the high-frequency cutoff band is realized by the proposed SSPPs structure.The influence of dispersion relation,electric field distribution,surface current,and structural parameters on the transmission characteristics of the proposed BPF are analyzed by finite difference time domain(FDTD).To validate the design concept,the prototype of the miniaturized SSPPs BPF has been manufactured and measured.The experimental results show high performance of the fabricated sample,in which the working in a range of 0.9 GHz-5.2 GHz with the relative bandwidth is 142%,the insertion loss less than 0.5 dB,the reflection coefficient less than-10 dB,and the group delay is less than one ns.This works provides a mirror for realizing the miniaturization of waveguides,and the application and development of high-confinement SSPPs functional devices in the microwave and THz regimes. 展开更多
关键词 spoof surface plasmon polaritons(SSPPs) bandpass filter ULTRA-WIDEBAND high-confinement
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Ultra-wideband surface plasmonic bandpass filter with extremely wide upper-band rejection
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作者 Xue-Wei Zhang Shao-Bin Liu +3 位作者 Qi-Ming Yu ling-ling wang Kun Liao Jian Lou 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期303-308,共6页
An ultra-wideband bandpass filter(BPF)with a wide out-of-band rejection based on a surface plasmonic waveguide(SPW)slotline with ring grooves is designed and analyzed.A paired microstrip-to-slotline transition is desi... An ultra-wideband bandpass filter(BPF)with a wide out-of-band rejection based on a surface plasmonic waveguide(SPW)slotline with ring grooves is designed and analyzed.A paired microstrip-to-slotline transition is designed for quasiTEM to TM mode conversion by using a microstrip line with a circular pad and the slotline with the same circular slot.The mode conversion between the TM and the surface plasmon polariton(SPP)mode is realized by using a gradient slotline with ring grooves and an impedance matching technique.The upper cut-off frequencies of the passband can be adjusted by using these proposed SPP units,while the lower frequencies of the passband are created by using the microstrip-toslotline transitions to give an ultra-wideband BPF.The dispersion curves of SPP units,electric field distribution,and the transmission spectra of the proposed ultra-wideband bandpass filter are all calculated and analyzed by the finite-difference time-domain(FDTD)method.The simulated results show that the presented filter has good performance including a wide3-dB bandwidth of 149%from 0.57 GHz to 3.93 GHz,an extremely wide 40-dB upper-band rejection from 4.2 GHz to18.5 GHz,and low loss and high selectivity in the passband.To prove the design validity,a prototype of the BPF has been manufactured and measured,showing a reasonable agreement with simulation results.The unique features of the proposed BPF may make it applicable for integrated circuit and plasmonic devices in microwave or THz frequency ranges. 展开更多
关键词 surface plasmonic waveguide(SPW) bandpass filter out-of-band rejection ULTRA-WIDEBAND
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Large eddy simulation of water flow over series of dunes
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作者 Jun LU ling-ling wang +1 位作者 Hai ZHU Hui-chao DAI 《Water Science and Engineering》 EI CAS 2011年第4期421-430,共10页
Large eddy simulation was used to investigate the spatial development of open channel flow over a series of dunes. The three-dimensional filtered Navier-Stokes (N-S) equations were numerically solved with the fracti... Large eddy simulation was used to investigate the spatial development of open channel flow over a series of dunes. The three-dimensional filtered Navier-Stokes (N-S) equations were numerically solved with the fractional-step method in sigma coordinates. The subgrid-scale turbulent stress was modeled with a dynamic coherent eddy viscosity model proposed by the authors The computed velocity profiles are in good agreement with the available experimental results. The mean velocity and the turbulent Reynolds stress affected by a series of dune-shaped structures were compared and analyzed. The variation of turbulence statistics along the flow direction affected by the wavy bottom roughness has been studied. The turbulent boundary layer in a complex geographic environment can be simulated well with the proposed large eddy simulation (LES) model. 展开更多
关键词 large eddy simulation (LES) DUNES turbulent boundary layer flow separation
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Image Restoration Using Hybrid Features Improvement on Morphological Component Analysis
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作者 Der-Chang Tseng Ru-Yin Wei +1 位作者 Ching-Ta Lu ling-ling wang 《Journal of Electronic Science and Technology》 CAS CSCD 2019年第4期371-381,共11页
Images are generally corrupted by impulse noise during acquisition and transmission.Noise deteriorates the quality of images.To remove corruption noise,we propose a hybrid approach to restoring a random noisecorrupted... Images are generally corrupted by impulse noise during acquisition and transmission.Noise deteriorates the quality of images.To remove corruption noise,we propose a hybrid approach to restoring a random noisecorrupted image,including a block matching 3D(BM3D)method,an adaptive non-local mean(ANLM)scheme,and the K-singular value decomposition(K-SVD)algorithm.In the proposed method,we employ the morphological component analysis(MCA)to decompose an image into the texture,structure,and edge parts.Then,the BM3D method,ANLM scheme,and K-SVD algorithm are utilized to eliminate noise in the texture,structure,and edge parts of the image,respectively.Experimental results show that the proposed approach can effectively remove interference random noise in different parts;meanwhile,the deteriorated image is able to be reconstructed well. 展开更多
关键词 Adaptive non-local mean(ANLM) block matching 3D(BM3D) image restoration morphological component analysis(MCA) singular value decomposition(SVD).
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Diabetes patients with comorbidities had unfavorable outcomes following COVID-19:A retrospective study
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作者 Shun-Kui Luo Wei-Hua Hu +10 位作者 Zhan-Jin Lu Chang Li Ya-Meng Fan Qi-Jian Chen Zai-Shu Chen Jian-Fang Ye Shi-Yan Chen Jun-Lu Tong ling-ling wang Jin Mei Hong-Yun Lu 《World Journal of Diabetes》 SCIE 2021年第10期1789-1808,共20页
BACKGROUND Previous studies have shown that diabetes mellitus is a common comorbidity of coronavirus disease 2019(COVID-19),but the effects of diabetes or anti-diabetic medication on the mortality of COVID-19 have not... BACKGROUND Previous studies have shown that diabetes mellitus is a common comorbidity of coronavirus disease 2019(COVID-19),but the effects of diabetes or anti-diabetic medication on the mortality of COVID-19 have not been well described.AIM To investigate the outcome of different statuses(with or without comorbidity)and anti-diabetic medication use before admission of diabetic after COVID-19.METHODS In this multicenter and retrospective study,we enrolled 1422 consecutive hospitalized patients from January 21,2020,to March 25,2020,at six hospitals in Hubei Province,China.The primary endpoint was in-hospital mortality.Epidemiological material,demographic information,clinical data,laboratory parameters,radiographic characteristics,treatment and outcome were extracted from electronic medical records using a standardized data collection form.Most of the laboratory data except fasting plasma glucose(FPG)were obtained in first hospitalization,and FPG was collected in the next day morning.Major clinical symptoms,vital signs at admission and comorbidities were collected.The treatment data included not only COVID-19 but also diabetes mellitus.The duration from the onset of symptoms to admission,illness severity,intensive care unit(ICU)admission,and length of hospital stay were also recorded.All data were checked by a team of sophisticated physicians.RESULTS Patients with diabetes were 10 years older than non-diabetic patients[(39-64)vs(56-70),P<0.001]and had a higher prevalence of comorbidities such as hypertension(55.5%vs 21.4%,P<0.001),coronary heart disease(CHD)(9.9%vs 3.5%,P<0.001),cerebrovascular disease(CVD)(3%vs 2.2%,P<0.001),and chronic kidney disease(CKD)(4.7%vs 1.5%,P=0.007).Mortality(13.6%vs 7.2%,P=0.003)was more prevalent among the diabetes group.Further analysis revealed that patients with diabetes who took acarbose had a lower mortality rate(2.2%vs 26.1,P<0.01).Multivariable Cox regression showed that male sex[hazard ratio(HR)2.59(1.68-3.99),P<0.001],hypertension[HR 1.75(1.18-2.60),P=0.006),CKD[HR 4.55(2.52-8.20),P<0.001],CVD[HR 2.35(1.27-4.33),P=0.006],and age were risk factors for the COVID-19 mortality.Higher HRs were noted in those aged≥65(HR 11.8[4.6-30.2],P<0.001)vs 50-64 years(HR 5.86[2.27-15.12],P<0.001).The survival curve revealed that,compared with the diabetes only group,the mortality was increased in the diabetes with comorbidities group(P=0.009)but was not significantly different from the noncomorbidity group(P=0.59).CONCLUSION Patients with diabetes had worse outcomes when suffering from COVID-19;however,the outcome was not associated with diabetes itself but with comorbidities.Furthermore,acarbose could reduce the mortality in diabetic. 展开更多
关键词 DIABETES Coronavirus disease 2019 MORTALITY Risk factors ACARBOSE
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森林火灾后云南高原森林真菌群落响应的物种特异性
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作者 ling-ling wang Qing-Qiu Zhou +6 位作者 Wen-Hua Su Yun-Jian Xu Qin-Dong Qian Xiong Yang De-Yun Chen Zhe Chen Jian-Ping Wu 《Journal of Plant Ecology》 SCIE CSCD 2023年第1期37-49,共13页
森林地下部分包含了丰富的真菌多样性。森林火灾产生的高温和对地上植被的破坏,会改变真菌的群落组成并影响后期森林的恢复。云南是我国重要的林区,也是森林火灾的频发区。本文旨在研究以云南松(Pinus yunnanensis)和柠檬桉(Eucalyptus ... 森林地下部分包含了丰富的真菌多样性。森林火灾产生的高温和对地上植被的破坏,会改变真菌的群落组成并影响后期森林的恢复。云南是我国重要的林区,也是森林火灾的频发区。本文旨在研究以云南松(Pinus yunnanensis)和柠檬桉(Eucalyptus citriodora)为主要树种的混交林在林冠火发生后地下真菌的响应。实验采集了两种树种下的矿质土、根际土和细根3个位点的样品,通过高通量测序手段,分析了真菌的多样性、群落组成、网络结构和生态营养型等信息。结果发现,3个采样点之间的群落组成具有显著性差异,矿质土壤中的alpha多样性高于根际土壤和细根中的alpha多样性。对于树种而言,柠檬桉的真菌网络复杂程度高于云南松。两种树种的前10个优势属以腐生真菌为主,其中云南松的毛霉菌门相对丰度高于柠檬桉。在生物标志物的比较中,云南松的根和根际土壤中均以外生菌根真菌为主,而柠檬桉的根和根际土壤则表现为以腐生真菌和共生真菌为主。我们的研究结果表明森林火灾后云南高原典型森林中真菌群落的响应具有物种特异性。 展开更多
关键词 真菌 林火 根际土 细根 云南松(Pinus yunnanensis) 柠檬桉(Eucalyptus citriodora) 云南高原
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Numerical investigation on interaction between regular waves and a fully submerged horizontal cylinder
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作者 Cheng Zeng Yu-die Hu +2 位作者 Yu-ran Yin Jie Zhou ling-ling wang 《Journal of Hydrodynamics》 SCIE EI CSCD 2023年第6期1101-1118,共18页
This paper presents a 2-D numerical investigation on interaction between regular waves and a fully submerged horizontal cylinder.A mathematical model of numerical wave tank with two-way fluid-solid interactions were d... This paper presents a 2-D numerical investigation on interaction between regular waves and a fully submerged horizontal cylinder.A mathematical model of numerical wave tank with two-way fluid-solid interactions were developed and validated.The wave-induced vibrations of a single-degree-of-freedom cylinder were simulated at eleven gap ratios(d/a=8,10,12,14,16,18,20,22,24,28 and 32).Numerical results indicate that significant nonlinear characteristics are introduced into the originally linear waves with the presence of cylinder.Based on the variation characteristics of cylinder vibration amplitude,the gap ratios can be divided into three ranges,i.e.,the uncertain range(8≤d/a≤14),quasi-linear range(14≤d/a≤20)and linear range(20≤d/a≤32).Under the same wave condition,the gap ratio does not affect the frequencies of vortex shedding and cylinder vibration.The presence of the cylinder complicates the flow field and suppress the vortex shedding around the cylinder. 展开更多
关键词 Numerical simulation linear wave wave-induced vibration gap ratio flow pattern
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Plasmonically induced transparency in double-layered graphene nanoribbons 被引量:7
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作者 SHENG-XUAN XIA XIANG ZHAI +1 位作者 ling-ling wang SHUANG-CHUN WEN 《Photonics Research》 SCIE EI 2018年第7期692-702,共11页
Near-field coupled plasmonic systems generally achieve plasmonically induced transparency(PIT) using only one-way bright–dark mode coupling. However, it is challenging to realize such well-designed devices,mainly bec... Near-field coupled plasmonic systems generally achieve plasmonically induced transparency(PIT) using only one-way bright–dark mode coupling. However, it is challenging to realize such well-designed devices,mainly because they depend significantly on the polarization direction. We exploit surface plasmons supported by two crossed layers of graphene nanoribbons(GNRs) to achieve dynamically tunable PIT, where each GNR operates as both the bright and dark modes simultaneously. The proposed PIT can result from either one-way bright–dark mode interactions or bidirectional bright–bright and bright–dark mode hybridized coupling when the polarization is perpendicular/parallel or at an angle to the GNRs, respectively.Additionally, identical ribbon widths yield polarization-insensitive single-window PIT, whereas different ribbon widths produce polarization-dependent double-window PIT. We examine the proposed technique using plasmon wave functions and the transfer matrix method; analytical and numerical results show excellent agreement. This study can provide physical insight into the PIT coupling mechanisms and advance the applicability and versatility of PIT-based sensing platforms and other active devices. 展开更多
关键词 近场耦合 等离子体系统 通讯技术 发展现状
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