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An investigation on the wind profiles and gravity wave dynamics in MLT region based on the meteor radars from the Meridian Project
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作者 Tai Liu Zhe Wang +2 位作者 MengXi Shi Willie Soon ShiCan Qiu 《Earth and Planetary Physics》 EI CAS 2025年第1期29-38,共10页
The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometri... The meteor radar can detect the zenith angle,azimuth,radial velocity,and altitude of meteor trails so that one can invert the wind profiles in the mesosphere and low thermosphere(MLT)region,based on the Interferometric and Doppler techniques.In this paper,the horizontal wind field,gravity wave(GW)disturbance variance,and GW fluxes are analyzed through the meteor radar observation from 2012−2022,at Mohe(53.5°N,122.4°E)and Zuoling(30.5°N,114.6°E)stations of the(Chinese)Meridian Project.The Lomb−Scargle periodogram method has been utilized to analyze the periodic variations for time series with observational data gaps.The results show that the zonal winds at both stations are eastward dominated,while the meridional winds are southward dominated.The variance of GW disturbances in the zonal and meridional directions increases gradually with height,and there is a strong pattern of annual variation.The zonal momentum flux of GW changes little with height,showing weak annual variation.The meridional GW flux varies gradually from northward to southward with height,and the annual periodicity is stronger.For both stations,the maximum values of zonal and meridional wind occur close to the peak heights of GW flux,with opposite directions.This observational evidence is consistent with the filtering theory.The horizontal wind velocity,GW flux,and disturbance variance of the GW at Mohe are overall smaller than those at Zuoling,indicating weaker activities in the MLT at Mohe.The power spectral density(PSD)calculated by the Lomb−Scargle periodogram shows that there are 12-month period and 6-month period in horizontal wind field,GW disturbance variance and GW flux at both stations,and especially there is also a 4-month cycle in the disturbance variance.The PSD of the 12-month and 6-month cycles exhibits maximum values below 88 km and above 94 km. 展开更多
关键词 meteor radar wind field gravity wave Lomb−Scargle method
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Unlocking the diversification benefits of DeFi for ASEAN stock market portfolios:a quantile study
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作者 Shoaib Ali Youssef Manel 《Financial Innovation》 2025年第1期38-63,共26页
This study examines the return connectedness between decentralized finance(DeFi)’s and the Association of Southeast Asian Nations(ASEAN)stock markets using the quantile vector autoregressive framework,which allows us... This study examines the return connectedness between decentralized finance(DeFi)’s and the Association of Southeast Asian Nations(ASEAN)stock markets using the quantile vector autoregressive framework,which allows us to investigate the connectedness at conditional quantiles.Our sample includes four major DeFi’s and six ASEAN stock markets,spanning from March 2018 to December 2022.The static results indicate a moderate level of return transmission between the system at mean and median quantile.This propagation increases substantially under extreme market conditions,establishing an asymmetric transmission across quantiles.Despite being a relatively new asset class,DeFi dominates the equity market and acts as the primary shock transmitter to the system in most instances.The dynamic analysis reveals that total system connectedness fluctuates over time and quantiles.The total system connectedness peaked during the COVID-19 and the Russia–Ukraine conflict period,indicating the impact of global events on system transmission.The optimal weight and hedge ratio estimated using the DCC-GARCH model indicate that DeFi is beneficial for portfolio construction and risk management.The rising trend in dynamic optimal weight and hedge ratio during the COVID-19 pandemic demonstrates that investors should decrease their investments in DeFi and increase hedging costs.Therefore,portfolio managers and investors should readjust their portfolio allocation in a timely manner according to different market states to build additional effective hedging and diversification strategies to avoid large losses and to reduce portfolio risk exposure. 展开更多
关键词 DeFi Quantile VAR ASEAN market DIVERSIFICATION HEDGING
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Mediterranean Berries as Inhibitors of Lipid Oxidation in Porcine Burger Patties Subjected to Cooking and Chilled Storage 被引量:17
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作者 Rui Ganho Mario Estévez +1 位作者 Mónica Armenteros David Morcuende 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第11期1982-1992,共11页
The efifciency of extracts from Arbutus unedo L. (AU), Crataegus monogyna L. (CM), Rosa canina L. (RC), and Rubus ulmifolius Schott. (RU) to inhibit lipid oxidation in raw, cooked and cooked and chilled (2... The efifciency of extracts from Arbutus unedo L. (AU), Crataegus monogyna L. (CM), Rosa canina L. (RC), and Rubus ulmifolius Schott. (RU) to inhibit lipid oxidation in raw, cooked and cooked and chilled (2°C/12 d) porcine burger patties, was investigated. The modiifcation of the fatty acid proifle during processing treatments (cooking and chilling), the quantitative measurements of thiobarbituric acid reactive substances (TBA-RS), and lipid-derived volatiles, were used as indicators of lipid oxidation. Polyunsaturated fatty acids (PUFA) gradually decreased during cooking and the subsequent storage of cooked burger patties with this decrease being signiifcantly greater (P〈0.05) in control patties than in those with added berry extracts. In accordance, the control patties showed signiifcantly higher TBA-RS numbers and counts of lipid-derived volatiles in all treatments when compared to the berry-added counterparts (P〈0.05). Results from the present work show, for the ifrst time, that extracts from A. unedo, C. monogyna, R. canina, and R. ulmifolius are promising antioxidants which could enhance the nutritional, safety and sensory properties of porcine burger patties. 展开更多
关键词 berries lipid oxidation meat pattiesm TBA-RSm polyunsaturated fatty acids lipid-derived volatiles
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Potential of Zimbabwean commercial probiotic products and strains of Lactobacillus plantarum as prophylaxis and therapy against diarrhoea caused by Escherichia coli in children 被引量:6
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作者 Walter Chingwaru Jerneja Vidmar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第1期57-62,共6页
Objective: To evaluate the potential of commercial fermented products sold in the country,and strains of Lactobacillus plantarum(L,plantarum)as prophylaxis and therapy against diarrhoea in children,Methods: The antimi... Objective: To evaluate the potential of commercial fermented products sold in the country,and strains of Lactobacillus plantarum(L,plantarum)as prophylaxis and therapy against diarrhoea in children,Methods: The antimicrobial potential of cultures of lactobacilli enriched from 4 Zimbabwean commercial food/beverage products: Dairibord Lacto sour milk(DLSM),Probrand sour milk(PSM),Kefalos Vuka cheese(KVC) and Chibuku opaque beer(COB); and four strains of L,plantarum obtained from Balkan traditional cheeses against clinical strains of Escherichia coli(E,coli) was assayed using the well diffusion method,Three commercial paediatric antidiarrhoeal drug products: Biogaia(BG),Prolife(PL) and Probio Junior(PJ) and a mutant strain of E,coli [strain 11105(ATCC)- a vitamin B-12 auxotroph and penicillin G acylase-producing strain] were used as controls,An agar diffusion assay and a competitive exclusion assay were carried out on Mueller Hinton agar,Results: Crude cultures of putative lactobacillus strains obtained from Zimbabwean dairy products(Probrand sour milk,Kefalos Vuka vuka cheese and Chibuku opaque beer) had significantly higher antimicrobial activities against clinical strains of E,coli than strains of L,plantarum isolated from Balkan cheeses(CLP1,CLP2 or CLP3) and crude microbial cultures from commercial paediatric probiotic products(BG,PJ and PL) of a culture of Lactobacillus rhamnosus LGG(P<0.05),Conclusions: The putative Lactobacilli from four commercial Zimbabwean dairy products(Probrand sour milk,Kefalos Vuka vuka cheese and Chibuku opaque beer),and three strains of L,plantarum from Balkan cheeses(CLP1,CLP2 or CLP3) exhibited high antibacterial activities that can be harnessed to control paediatric diarrhoea that is caused by pathogenic strains of E,coli,Studies to characterise the probiotic potential of the live cultures in the products and the new strains of L,plantarum are underway. 展开更多
关键词 Probiotic Inhibition Escherichia coli Lactobacillus plantarum DIARRHOEA PAEDIATRIC
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Animal models used to study direct peripheral nerve repair: a systematic review 被引量:2
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作者 Francisco Javier Vela Guadalupe Martínez-Chacón +3 位作者 Alberto Ballestín JoséLuis Campos Francisco Miguel Sánchez-Margallo Elena Abellán 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第3期491-502,共12页
Objective:Peripheral nerve repair is required after traumatic injury.This common condition represents a major public health problem worldwide.Recovery after nerve repair depends on several factors,including the severi... Objective:Peripheral nerve repair is required after traumatic injury.This common condition represents a major public health problem worldwide.Recovery after nerve repair depends on several factors,including the severity of the injury,the nerve involved,and the surgeon’s technical skills.Despite the precise microsurgical repair of nerve lesions,adequate functional recovery is not always achieved and,therefore,the regeneration process and surgical techniques are still being studied.Pre-clinical animal models are essential for this research and,for this reason,the focus of the present systematic review(according to the PRISMA statement)was to analyze the different animal models used in pre-clinical peripheral nerve repair studies.Data sources:Original articles,published in English from 2000 to 2018,were collected using the Web of Science,Scopus,and PubMed databases.Data selection:Only preclinical trials on direct nerve repair were included in this review.The articles were evaluated by the first two authors,in accordance with predefined data fields.Outcome measures:The primary outcomes included functional motor abilities,daily activity and regeneration rate.Secondary outcomes included coaptation technique and animal model.Results:This review yielded 267 articles,of which,after completion of the screening,49 studies were analyzed.There were 1425 animals in those 49 studies,being rats,mice,guinea pigs,rabbits,cats and dogs the different pre-clinical models.The nerves used were classified into three groups:head and neck(11),forelimb(8)and hindlimb(30).The techniques used to perform the coaptation were:microsuture(46),glue(12),laser(8)and mechanical(2).The follow-up examinations were histology(43),electrophysiological analysis(24)and behavioral observation(22).Conclusion:The most widely used animal model in the study of peripheral nerve repair is the rat.Other animal models are also used but the cost-benefit of the rat model provides several strengths over the others.Suture techniques are currently the first option for nerve repair,but the use of glues,lasers and bioengineering materials is increasing.Hence,further research in this field is required to improve clinical practice. 展开更多
关键词 NERVE MICROSURGERY peripheral NERVE regeneration REPAIR reconstruction DIRECT NERVE REPAIR animal model coaptation PRISMA systematic review
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Effects of Aerosol Vertical Inhomogeneity on the Upwelling Radiance and Satellite Remote Sensing of Surface Reflectance 被引量:2
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作者 邱金桓 Nobuo Takeuchi 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2001年第4期539-553,共15页
There are two widely used radiative models without consideration of aerosol inhomogeneity for satellite remote sensing application, the Homogeneous Model and the Two-layer Model with aerosol in the lower layer. In thi... There are two widely used radiative models without consideration of aerosol inhomogeneity for satellite remote sensing application, the Homogeneous Model and the Two-layer Model with aerosol in the lower layer. In this paper, effects of the aerosol vertical inhomogeneity on upwelling radiance and satellite remote sensing of surface reflectance are analyzed through numerical simulations by using two models. As shown in the simulations by using 24 representative aerosol models, there is often a considerably large error in upwel-ling radiance calculated by two models (Homogeneous and Two-layer) for the short wavelength channel with strong molecular scattering, owing to the difference between molecular and aerosol scattering proper-ties. For the long wavelength channel, the error is small if aerosol optical parameters are less variable with height, but it could also be significant if there are aerosol layers with different scattering phase functions and single scattering albedo. The radiance errors by the Homogeneous Model and the Two-layer Model can be up to 31.4% and 31.5% for the clean atmosphere, and in case of turbid atmosphere 67.8% and 59.2%, respectively. The radiance error could result in a large uncertainty of surface reflectance retrievals, especially for the short wavelength channel and the strongly absorbing aerosol. For the turbid atmosphere with strong-ly absorbing aerosol, the Homogeneous Model and the Two-layer Model are not suitable for atmospheric correction application. Key words Satellite remote sensing - Aerosol inhomogeneity - Surface reflectance - Radiance 展开更多
关键词 Satellite remote sensing Aerosol inhomogeneity Surface reflectance RADIANCE
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Evidences supporting the vascular etiology of post-double balloon enteroscopy pancreatitis:Study in porcine model 被引量:1
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作者 Rafael Latorre Octavio López-Albors +4 位作者 Federico Soria Esther Morcillo Pilar Esteban Enrique Pérez-Cuadrado-Robles Enrique Pérez-Cuadrado-Martínez 《World Journal of Gastroenterology》 SCIE CAS 2017年第34期6201-6211,共11页
Double balloon enteroscopy(DBE)is an endoscopic technique broadly used to diagnose and treat small bowel diseases.Among the associated complications of the oral DBE,post-procedure pancreatitis has taken the most atten... Double balloon enteroscopy(DBE)is an endoscopic technique broadly used to diagnose and treat small bowel diseases.Among the associated complications of the oral DBE,post-procedure pancreatitis has taken the most attention due to its gravity and the thought that it might be associated to the technique itself and anatomical features of the pancreas.However,as the etiology has not been clarified yet,this paper aims to review the published literature and adds new results from a porcine animal model.Biochemical markers,histological sections and the vascular perfusion of the pancreas were monitored in the pig during DBE practice.A reduced perfusion of the pancreas and bowel,the presence of defined hypoxic areas and disseminated necrotic zones were found in the pancreatic tissue of pigs.All these evidences contribute to support a vascular distress as the most likely etiology of the post-DBE pancreatitis. 展开更多
关键词 Double balloon enteroscopy PANCREAS Animal model PANCREATITIS PIG
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Effect of double-balloon enteroscopy on pancreas:An experimental porcine model 被引量:1
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作者 Rafael Latorre Federico Soria +5 位作者 Octavio López-Albors Ricardo Sarriá Francisco Sánchez-Margallo Pilar Esteban Fernando Carballo Enrique Pérez-Cuadrado 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第37期5181-5187,共7页
AIM: To evaluate the effect of double-balloon enteros- copy (DBE) on pancreas histology and levels of pancre- atic enzymes. METHODS: Conventional upper gastrointestinal endos- copy was performed on five control pi... AIM: To evaluate the effect of double-balloon enteros- copy (DBE) on pancreas histology and levels of pancre- atic enzymes. METHODS: Conventional upper gastrointestinal endos- copy was performed on five control pigs. Oral DBE was performed with an EN-450T5 enteroscope on 20 pigs. Two experimental groups (10 pigs each) were defined according to DBE duration: 90 rain for Group 1 and 140 min for Group 2. During oral insertion, the balloons were not inflated in the descending part of the duodenum to avoid the minor duodenal papilla. Serum amy- lase, lipase and C-reactive protein (CRP) levels were monitored before the procedure and repeated every 30 min until the exploration was finished, as well as 24 h and 7 d after. After the procedure and for a total of 7 d, the pigs were observed twice a day for signs of de- creased activity, irritability, vomiting or anorexia. Gross and microscopic examination of the pancreas was per- formed on day 7. RESULTS: All animals tolerated DBE without clini- cal manifestations of acute pancreatitis. Experimental groups had higher levels of enzymes than the control group at 24 h. Throughout the exploration, the amylase levels increased significantly above the baseline 24 h after DBE, although the increase was not statistically significant and did not reach 20% of the baseline. An increase in lipase and CRP was observed at 24 h after the procedure, although by day 7, all enzymatic lev- els had returned to baseline. No differences between Groups 1 and 2 were found for any enzyme and sam- pling site during and after the procedure. Similarly, no correlation between insertion depth and enzyme levels was observed. Direct in situ and post-removal inspec- tion of the pancreas did not show any evidence of fluid collection, abscesses or hemorrhage. Histological examination of the pancreas from Groups 1 and 2 re- vealed the existence of focal areas (0.14-0.26 mm2) of ischemic necrosis in 47.4% of the animals. In the pigs with damaged pancreas, the left lobe (tail) was always affected. However, this only happened in 83.3% of the samples from the right lobe (head) and in 33.3% of the samples from the body of the pancreas. Significant differences were found between the left lobe (tail) and the body for the percentage of affected pancreas. Both the size of the lesions and the percentage of affected pancreas were higher in the left pancreatic lobe (tail). The presence of the lesions was not related to the ex- ploration length.CONCLUSION: The increase in pancreatic enzymes after DBE could be related to focal points of pancreatic ischemic necrosis due to mechanical stress. 展开更多
关键词 ENDOSCOPY PANCREATITIS Double-balloon en-teroscopy Experimental study Pig model
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Interrelationship Analysis of L-Band Backscattering Intensity and Soil Dielectric Constant for Soil Moisture Retrieval Using PALSAR Data 被引量:1
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作者 Saeid Gharechelou Ryutaro Tateishi Josaphat Tetuko Sri Sumantyo 《Advances in Remote Sensing》 2015年第1期15-24,共10页
The purpose of this paper is to study about the interrelationship between the backscattering intensity of PALSAR data and the laboratory measurement of dielectric constant and soil moisture. The characterization of th... The purpose of this paper is to study about the interrelationship between the backscattering intensity of PALSAR data and the laboratory measurement of dielectric constant and soil moisture. The characterization of the dielectric constant of arid soils in the 0.3 - 3 GHz frequency range, particularly focused in L-band was analyzed in varied soil moisture content and soil textures. The interrelationship between the relative dielectric constant with soil textures and backscattering of PALSAR data was also analyzed and statistical model was computed. In this study, after collecting the soil samples in the field from top soil (0 - 10 cm) in a homogeneous area then, the dielectric constant was measured using a dielectric probe tool kit. For investigated of the characteristics and behaviors of the dielectric constant and relationship with backscattering a variety of moisture content from 0% to 40% and soil fraction conditions was tested in laboratory condition. All data were analyzed by integrating it with other geophysical data in GIS, such as land cover and soil texture. Thus, the regression model computed between measured soil moisture and backscattering coefficient of PALSR data which were extracted as same point of each soil sample pixel. Finally, after completing the preprocessing, such as removing the speckle noise by averaging, the model was applied to the PALSAR data for retrieving the soil moisture map in arid region of Iran. The analysis of dielectric constant properties result has shown the soil texture after the moisture content has the largest effected on dielectric constant. In addition, the PALSAR data in dual polarization are also able to derive the soil moisture using statistical method. The dielectric constant and backscattering shown have the exponential relationship and the HV polarization mode is more sensitive than the HH mode to soil moisture and overestimated the soil moisture as well. The validation of result has shown the 4.2 Vol-% RMSE of soil moisture. It means that the backscattering analysis should consider about other factors such a surface roughness and mix pixel of vegetation effective. 展开更多
关键词 SAR Dielectric Constant SOIL Moisture ARID SOIL BACKSCATTERING SOIL Texture PALSAR Data
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Integrated Use of Existing Global Land Cover Datasets for Producing a New Global Land Cover Dataset with a Higher Accuracy: A Case Study in Eurasia 被引量:1
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作者 Naijia Zhang Ryutaro Tateishi 《Advances in Remote Sensing》 2013年第4期365-372,共8页
It has been commonly acknowledged that the current global mapping projects have encountered the accuracy challenge. By conducting a comparison among the four existing global land cover datasets (MODIS LC, GLC2000, GLC... It has been commonly acknowledged that the current global mapping projects have encountered the accuracy challenge. By conducting a comparison among the four existing global land cover datasets (MODIS LC, GLC2000, GLCNMO and GLOBCOVER), it has been identified that certain areas’ accuracy has dragged down the overall accuracy of these global land cover datasets. In this paper, those areas have been defined as the “unreliable area”. This study has recollected the training data from the “unreliable area” within the above four mentioned datasets and reclassified the “unreliable area” by using two supervised classifications. The final result has shown that compared with any existing datasets, a relatively higher accuracy has been able to achieve. 展开更多
关键词 GLOBAL Land COVER GLCNMO Training Data ACCURACY
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Estimating Hansen solubility parameters of organic pigments by group contribution methods 被引量:2
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作者 Markus Enekvist Xiaodong Liang +2 位作者 Xiangping Zhang Kim Dam-Johansen Georgios MKontogeorgis 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第3期186-197,共12页
The Hansen solubility parameters(HSP)are frequently used for solvent selection and characterization of polymers,and are directly related to the suspension behavior of pigments in solvent mixtures.The performance of cu... The Hansen solubility parameters(HSP)are frequently used for solvent selection and characterization of polymers,and are directly related to the suspension behavior of pigments in solvent mixtures.The performance of currently available group contribution(GC)methods for HSP were evaluated and found to be insufficient for computer-aided product design(CAPD)of paints and coatings.A revised and,for this purpose,improved GC method is presented for estimating HSP of organic compounds,intended for organic pigments.Due to the significant limitations of GC methods,an uncertainty analysis and parameter confidence intervals are provided in order to better quantify the estimation accuracy of the proposed approach.Compared to other applicable GC methods,the prediction error is reduced significantly with average absolute errors of 0.45 MPa^(1/2),1.35 MPa^(1/2),and 1.09 MPa^(1/2) for the partial dispersion(δD),polar(δP)and hydrogen-bonding(δH)solubility parameters respectively for a database of 1106 compounds.The performance for organic pigments is comparable to the overall method performance,with higher average errors forδD and lower average errors forδP andδH. 展开更多
关键词 Hansen solubility parameters Group contribution method Organic pigments Computer-aided product design Parameter estimation Uncertainty analysis
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Acute Pulmonary Embolism, Multiple Coronary Thrombosis, and Thrombi in the Left Ventricle and Ascending Aorta in a Patient with COVID-19 Infection 被引量:1
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作者 David Chipayo Gonzales Paloma Pérez Espejo +4 位作者 Breda Hennessey Javier Fernández Portales Sebastián Romani Iván Núñ ez Gil 《Case Reports in Clinical Medicine》 2021年第10期314-322,共9页
Both arterial and venous thromboembolic events are common in patients hospitalized in intensive care units with severe COVID-19. These patients often have laboratory findings consistent with a hypercoagulable state, s... Both arterial and venous thromboembolic events are common in patients hospitalized in intensive care units with severe COVID-19. These patients often have laboratory findings consistent with a hypercoagulable state, suggesting widespread thrombosis and fibrinolysis, as well as elevated levels of D-dimer, von Willebrand factor (VWF), and factor VIII. There is increasing evidence that these thromboembolic events are associated with worse outcomes. We present the case of a 61-year-old man admitted for bilateral pneumonia due to COVID-19 infection, who developed during his hospitalization;Bilateral pulmonary thromboembolism, an acute myocardial infarction due to multiple coronary thrombosis, an intracavitary thrombus and thrombus in the ascending aorta. The patient was treated with systemic fibrinolysis and full doses of anticoagulation for pulmonary embolism, an emergency primary percutaneous coronary intervention (PCI) was performed with the implant of a drug eluting stent (DES) in the left anterior descending artery (LAD). Triple therapy with aspirin, clopidogrel and heparin was maintained until discharge. After the patient discharge, aspirin was stopped and treatment with clopidogrel and dabigatran was maintained for three months. In a subsequent outpatient control, the thrombi of the left ventricle and the ascending aorta resolved. 展开更多
关键词 COVID 19 Infection Pulmonary Embolism (PE) ST-Segment Elevation Myocardial Infarction (STEMI) Intracoronary Thrombosis Intra-Aortic Thrombus
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Mammalian cell cultures as models for Mycobacterium tuberculosis-human immunodeficiency virus(HIV) interaction studies:A review
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作者 Walter Chingwaru Richard H.Glashoff +2 位作者 Jerneja Vidmar Petrina Kapewangolo Samantha L.Sampson 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第9期809-816,共8页
Mycobacterium tuberculosis(MTB) and human immunodeficiency virus(HIV) co-infections have remained a major public health concern worldwide,particularly in Southern Africa.Yet our understanding of the molecular interact... Mycobacterium tuberculosis(MTB) and human immunodeficiency virus(HIV) co-infections have remained a major public health concern worldwide,particularly in Southern Africa.Yet our understanding of the molecular interactions between the pathogens has remained poor,primarily due to lack of suitable preclinical models for such studies.We reviewed the use,this far,of mammalian cell culture models in HIV-MTB interaction studies.Studies have described the use of primary human cell cultures,including monocyte-derived macrophage(MDM) fractions of peripheral blood mononuclear cell(PBMC),alveolar macrophages(AM),cell lines such as the monocyte-derived macrophage cell line(U937),T lymphocyte cell lines(CEMx174,ESAT-6-specific CD4+ T-cells) and an alveolar epithelial cell line(A549) and special models such as stem cells,three dimensional(3D) or organoid cell models [including a blood-brain barrier(BBB) cell model] in HIV-MTB interaction studies.The use of cell cultures from other mammals,including:mouse cell lines [macrophage cell lines RAW 264.7 and J774.2,fibroblast cell lines(NIH 3T3,C3 H clones),embryonic fibroblast cell lines and T-lymphoma cell lines(S1A.TB,TIMI.4 and R1.1)]; rat(T cells:Rat2,RGE,XC and HH16,and alveolar cells:NR8383) and primary guinea pigs derived AMs,in HIV-MTB studies is also described.Given the spectrum of the models available,cell cultures offer great potential for host-HIV-MTB interactions studies. 展开更多
关键词 HIV MYCOBACTERIUM TUBERCULOSIS CELL lines Primary CELL MODELS CO-INFECTION
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Genetic Correlation between Agronomically Important Traits in Yellow Passion Fruit 被引量:1
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作者 Leonarda Grillo Neves Claudio Horst Bruckner +5 位作者 Marcelo Coutinho Picanco Severino de Paiva Sobrinho Kelly Lana Araújo Petterson Baptista da Luz Marco Antonio Aparecido Barelli Willian Krause 《American Journal of Plant Sciences》 2013年第11期2112-2117,共6页
Breeding programs have sought to determine the minimum period of genotype evaluation, which is a long term-process. The objective of this work was to determine the association between qualitative traits of yellow pass... Breeding programs have sought to determine the minimum period of genotype evaluation, which is a long term-process. The objective of this work was to determine the association between qualitative traits of yellow passion fruit (Passiflora edulis Sims) and relate maturity to other characteristics. To carry out this work, 113 families of full-sibs and half-sibs were planted in Vi&ccedil;osa (MG), Brazil, in a randomized block experimental design arranged in sets (treatment groups). The association between the analyzed characteristics was studied using path analysis and canonical correlation techniques. It was found that lower-yielding but larger-fruit bearing genotypes of passion fruit plant also require more days until reaching anthesis. Round-shaped fruits are linked to higher contents of total soluble solids. More intense pulp color also indicates higher contents of total soluble solids. The riper the fruit, the more intensely orange is the color of the pulp. The ratio between the levels of total soluble solids and total titrimetric acidity was the main determinant of pulp color for passion fruit. 展开更多
关键词 Canonical Correlation Passiflora edulis Path Correlation
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Effects of normobaric cyclic hypoxia exposure on mesenchymal stem-cell differentiation–pilot study on bone parameters in elderly
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作者 Marta Camacho-Cardenosa JoséManuel Quesada-Gómez +4 位作者 Alba Camacho-Cardenosa Alejo Leal GabrielDorado Bárbara Torrecillas-Baena Antonio Casado-Díaz 《World Journal of Stem Cells》 SCIE 2020年第12期1667-1690,共24页
BACKGROUND Mesenchymal stem cells(MSC)of bone marrow are the progenitor of osteoblasts and adipocytes.MSC tend to differentiate into adipocytes,instead of osteoblasts,with aging.This favors the loss of bone mass and d... BACKGROUND Mesenchymal stem cells(MSC)of bone marrow are the progenitor of osteoblasts and adipocytes.MSC tend to differentiate into adipocytes,instead of osteoblasts,with aging.This favors the loss of bone mass and development of osteoporosis.Hypoxia induces hypoxia inducible factor 1αgene encoding transcription factor,which regulates the expression of genes related to energy metabolism and angiogenesis.That allows a better adaptation to low O2 conditions.Sustained hypoxia has negative effects on bone metabolism,favoring bone resorption.Yet,surprisingly,cyclic hypoxia(CH),short times of hypoxia followed by long times in normoxia,can modulate MSC differentiation and improve bone health in aging.AIM To evaluate the CH effect on MSC differentiation,and whether it improves bone mineral density in elderly.METHODS MSC cultures were induced to differentiate into osteoblasts or adipocytes,in CH(3%O2 for 1,2 or 4 h,4 d a week).Extracellular-matrix mineralization and lipid-droplet formation were studied in MSC induced to differentiate into osteoblast or adipocytes,respectively.In addition,gene expression of marker genes,for osteogenesis or adipogenesis,have been quantified by quantitative real time polymerase chain reaction.The in vivo studies with elderly(>75 years old;n=10)were carried out in a hypoxia chamber,simulating an altitude of 2500 m above sea level,or in normoxia,for 18 wk(36 CH sessions of 16 min each).Percentages of fat mass and bone mineral density from whole body,trunk and right proximal femur(femoral,femoral neck and trochanter)were assessed,using dual-energy X-ray absorptiometry.RESULTS CH(4 h of hypoxic exposure)inhibited extracellular matrix mineralization and lipid-droplet formation in MSC induced to differentiate into osteoblasts or adipocytes,respectively.However,both parameters were not significantly affected by the other shorter hypoxia times assessed.The longest periods of hypoxia downregulated the expression of genes related to extracellular matrix formation,in MSC induced to differentiate into osteoblasts.Interestingly,osteocalcin(associated to energy metabolism)was upregulated.Vascular endothelial growth factor an expression and low-density lipoprotein receptor related protein 5/6/dickkopf Wnt signaling pathway inhibitor 1(associated to Wnt/β-catenin pathway activation)increased in osteoblasts.Yet,they decreased in adipocytes after CH treatments,mainly with the longest hypoxia times.However,the same CH treatments increased the osteoprotegerin/receptor activator for nuclear factor kappa B ligand ratio in both cell types.An increase in total bone mineral density was observed in elderly people exposed to CH,but not in specific regions.The percentage of fat did not vary between groups.CONCLUSION CH may have positive effects on bone health in the elderly,due to its possible inhibitory effect on bone resorption,by increasing the osteoprotegerin/receptor activator for nuclear factor kappa B ligand ratio. 展开更多
关键词 Normobaric cyclic hypoxia Mesenchymal stem cells Cellular differentiation OSTEOBLASTS ADIPOCYTES Bone health
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Global Standards and Local Policies for School Diabetes Care
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作者 María J. Miranda Velasco Maria Gloria Solís Galán Enma Domínguez Martín 《Health》 2015年第12期1642-1650,共9页
Objectives: The purpose of this study is to analyse the practical implementation of regional and na-tional policies through the Protocol of Care of Children and Adolescents in School (2010) in Extremadura Region (Spai... Objectives: The purpose of this study is to analyse the practical implementation of regional and na-tional policies through the Protocol of Care of Children and Adolescents in School (2010) in Extremadura Region (Spain), and to compare its contents with the international standards of diabetes care at school defined by American Diabetes Association and International Diabetes Federation. The measures not only affect the security and diabetes care, but also inclusion and the right to health. Methods: A documental comparative analysis between the local and international standards about diabetes care in school setting is carried out. This analysis is framed in a larger project focused on the study of health promoting school and diabetes education, in which perceptions of children and adolescents with diabetes, their parents and school staff were studied. Results: The Protocol of Care of Children and Adolescents in School (2010) contains some international recommendations about the care of T1DM at school, but in other cases the measures are non-specific. The distribution of responsibilities for care at school is unclear and no monitoring and evaluation indicators are defined. Some elements are identified to be implemented in the tool to favour the security, management of T1DM care and wellbeing. In general, these elements refer to school plan for diabetes care, school organization and teachers, and school community training. Conclusion: It is required to develop specific policies and decisive action to ensure the right to health of children with diabetes and the full application of international standards for diabetes care at school. 展开更多
关键词 Health Policy CHILDHOOD and Adolescents Diabetes CARE SCHOOL SETTING INCLUSION
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New urban map of Eurasia using MODIS and multi-source geospatial data
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作者 Bayan Alsaaideh Ryutaro Tateishi +3 位作者 Dong Xuan Phong Nguyen Thanh Hoan Ahmad Al-Hanbali Bai Xiulian 《Geo-Spatial Information Science》 SCIE EI CSCD 2017年第1期29-38,共10页
Urban areas are of paramount significance to both the individuals and communities at local and regional scales.However,the rapid growth of urban areas exerts effects on climate,biodiversity,hydrology,and natural ecosy... Urban areas are of paramount significance to both the individuals and communities at local and regional scales.However,the rapid growth of urban areas exerts effects on climate,biodiversity,hydrology,and natural ecosystems worldwide.Therefore,regular and up-to-date information related to urban extent is necessary to monitor the impacts of urban areas at local,regional,and potentially global scales.This study presents a new urban map of Eurasia at 500 m resolution using multi-source geospatial data,including Moderate Resolution Imaging Spectroradiometer(MODIS)data of 2013,population density of 2012,the Defense Meteorological Satellite Program’s Operational Linescan System(DMSP-OLS)nighttime lights of 2012,and constructed Impervious Surface Area(ISA)data of 2010.The Eurasian urban map was created using the threshold method for these data,combined with references of fine resolution Landsat and Google Earth imagery.The resultant map was compared with nine global urban maps and was validated using random sampling method.Results of the accuracy assessment showed high overall accuracy of the new urban map of 94%.This urban map is one product of the 20 land cover classes of the next version of Global Land Cover by National Mapping Organizations. 展开更多
关键词 Urban area mapping population density MODIS data integration accuracy assessment EURASIA
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A Novel Ensemble Learning System for Cyberattack Classification
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作者 óscar Mogollón-Gutiérrez JoséCarlos Sancho Nunez +1 位作者 Marávila Vegas Andrés Caro Lindo 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1691-1709,共19页
Nowadays,IT systems rely mainly on artificial intelligence(AI)algorithms to process data.AI is generally used to extract knowledge from stored information and,depending on the nature of data,it may be necessary to app... Nowadays,IT systems rely mainly on artificial intelligence(AI)algorithms to process data.AI is generally used to extract knowledge from stored information and,depending on the nature of data,it may be necessary to apply different AI algorithms.In this article,a novel perspective on the use of AI to ensure the cybersecurity through the study of network traffic is presented.This is done through the construction of a two-stage cyberattack classification ensemble model addressing class imbalance following a one-vs-rest(OvR)approach.With the growing trend of cyberattacks,it is essential to implement techniques that ensure legitimate access to information.To address this issue,this work proposes a network traffic classification system for different categories based on several AI techniques.In the first task,binary models are generated to clearly differentiate each type of traffic from the rest.With binary models generated,an ensemble model is developed in two phases,which allows the separation of legitimate and illegitimate traffic(phase 1)while also identifying the type of illegitimate traffic(phase 2).In this way,the proposed system allows a complete multiclass classification of network traffic.The estimation of global performance is done using a modern dataset(UNSW-NB15),evaluated using two approaches and compared with other state-of-art works.Our proposal,based on the construction of a two-step model,reaches an F1 of 0.912 for the first level of binary classification and 0.7754 for the multiclass classification.These results show that the proposed system outperforms other state-of-the-art approaches(+0.75%and+3.54%for binary and multiclass classification,respectively)in terms of F1,as demon-strated through comparison together with other relevant classification metrics. 展开更多
关键词 Intrusion detection ensemble learning two-phase model UNSW-NB15 CYBERSECURITY
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以色列严重退化旱地长期恢复对土壤和植被的影响
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作者 Ilan STAVI Manuel PULIDO FERNáNDEZ Eli ARGAMAN 《Journal of Geographical Sciences》 SCIE CSCD 2023年第3期529-546,共18页
Land degradation affects extensive drylands around the world.Due to long-term misuse,the Israeli Sde Zin dryland site has faced severe degradation.The study objective was to assess the feasibility of passive restorati... Land degradation affects extensive drylands around the world.Due to long-term misuse,the Israeli Sde Zin dryland site has faced severe degradation.The study objective was to assess the feasibility of passive restoration in recovering the site.The study was conducted in four land-units along a preservation-degradation continuum:(1)an area that has not faced anthropogenic disturbances(Ecological land);(2)an area that was proclaimed as a national park in the 1970s(Rehabilitation);(3)an area that was prone,until recently,to moderate anthropogenic pressures(Triangle);and(4)a dirt road that was subjected to long-term off-road traffic(Dirtroad).Soil was sampled and analyzed for its properties.The soil physical quality followed the trend of Ecological land>Rehabilitation>Triangle>Dirtroad.Specifically,high soil salinity in the latter three land-units is attributed to long-term erosional processes that exposed the underlying salic horizons.Herbaceous and shrubby vegetation cover was also monitored.The herbaceous vegetation cover followed the trend of Ecological land(86.4%)>Rehabilitation(40.3%)>Triangle(26.2%)>Dirtroad(2.1%),while the shrubby cover was 2.8%in the Ecological land-unit,and practically zero in the other land-units.It seems that despite the effectiveness of passive restoration in recovering the soil’s physical properties,the recovery of vegetation is limited by the severe soil salinity. 展开更多
关键词 active rehabilitation ecosystem functions land-use change land degradation and desertification annual vs.perennial plants self-restoration
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