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Health care service usage and costs for high-needs elderly patients with heart failure

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Journal of Geriatric Cardiology 2020年第9期17卷 580-584页

作者： Alessandra Buja Riccardo Caberlotto Carlo Pinato Giulia Grotto Maria Chiara Corti Francesco Avossa Elena schievano Vincenzo Baldo Department of Cardiologic Vascular and Thoracic Sciencesand Public HealthUniversity of PaduaPadovaItaly school of specialization in Hygiene Preventive Medicine and Public HealthUniversity of PaduaPadovaItaly Azienda Zero UnitàOperativa Complessa“Servizio Epidemiologico Regionale e Registri”Italy

Heart failure(HF)has been defined as global disease of pandemic proportions,since it affects around 26 million people worldwide.[1]According to a recent study,age is the most important factor influencing the prevalence of HF,as it is for most other chronic conditions.[2]This means that,with the predicted aging of the population(the proportion of the world’s population aged 60 years and over will nearly double from 2015 to 2050),[3]there will be a growth in the total burden of HF,and a rise in the number of comorbidities in HF patients.According to a recent study,almost 86%of adults with HF have two or more comorbid conditions.[4]Comorbidity,defined as the co-existence of one or more additional conditions in individuals with a specified index medical condition,[5]adds to the complexity of treating elderly patients with HF.

关键词： Heart failure Healthcare service costs Healthcare service usage Multimorbidity

Thermodynamic Performance and Flammability studies of Hydrocarbon Based Low Global Warming Potential Refrigerant Mixtures

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Journal of Thermal science 2022年第5期31卷 1487-1502页

作者： Nagarjuna KUMMA s s Harish KRUTHIVENTI Department of Mechanical Engineering Low Temperature LaboratoryNational Institute of TechnologyTiruchirappalliTrichy620015India

This paper presents a theoretical method to calculate the minimum inerting concentration(MIC)of binary and ternary blends(refrigerants)that are used in small refrigeration systems.MIC is the concentration of the dilutant which makes the flammable mixture into just non-flammable(at non-zero quenching potential).In this study,the refrigerant safety parameters such as flammability,Global Warming Potential(GWP)and performance(COP)are analyzed for twelve binary and thirteen ternary blends containing one flammable and two nonflammable(dilutant)components.Flammability investigation was carried out with the hydrocarbon refrigerants R290,R600,R600a each mixed with dilutants R227ea,R125,R245fa,R13I1 and R134a at different concentrations respectively.Two methods,thermal balance method(TBM)and modified thermal balanced method(MTBM),are used to estimate the MIC(which decides the flammable zone).Thirteen ternary blends were identified based on the MIC values estimated using MTBM.In the case of ternary blends,it was observed that the non-flammable zone is high for the compositions of the Mixture G,Mixture H and Mixture I.It was also estimated that the COPs of the proposed mixtures M22,M24,M25 and M27 are 4%greater than the COP of R134a(for the same operating conditions).Further,it was also understood that the corresponding GWP value is reduced by 90%to 97%for the mixtures(M21,M22,M24,M25 and M27)when compared to R134a(GWP=1300).Therefore,out of the thirteen proposed ternary mixtures(M15 to M27),the mixtures(M21,M22,M24,M25 and M27)are safe in terms of flammability,GWP and possess reasonable COP which can be a potential alternative refrigerant mixture to R134a in small refrigeration systems.

关键词： hydrocarbons minimum inerting concentration ternary Global Warming Potential

碳纳米管-二氧化钛纳米复合材料的合成及纳米流体驱油实验

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石油勘探与开发 2022年第6期49卷 1234-1241页

作者： DIBAJI A s RAsHIDI A BANIYAGHOOB s sHAHRABADI A 伊朗伊斯兰阿扎德大学德黑兰14515-775伊朗伊朗石油工业研究院纳米科技研究中心德黑兰14665-1998伊朗伊朗石油工业研究院石油工程所德黑兰***伊朗

为了同时利用(类)金属氧化物和碳纳米材料在提高采收率方面的作用,合成了碳纳米管-二氧化钛(CNT-TiO_(2))纳米复合材料,用接触角、界面张力和乳液稳定性等评价其性能,通过玻璃刻蚀模型驱油实验评估CNT-TiO_(2)纳米流体驱油效果。合成的C... 详细信息

为了同时利用(类)金属氧化物和碳纳米材料在提高采收率方面的作用,合成了碳纳米管-二氧化钛(CNT-TiO_(2))纳米复合材料,用接触角、界面张力和乳液稳定性等评价其性能,通过玻璃刻蚀模型驱油实验评估CNT-TiO_(2)纳米流体驱油效果。合成的CNT-TiO_(2)纳米复合材料由二氧化钛基体和碳纳米管增强相组成,二氧化钛为主要的结晶相,二氧化钛纳米颗粒覆盖在碳纳米管上。CNT-TiO_(2)能够将岩石的润湿性从油湿变为水湿,并降低油水界面张力。CNT-TiO_(2)可提高Pickering乳液的稳定性,在90℃条件下形成的乳液仍能保持稳定;NaCl质量分数高达2%时,配制的乳液在静置7 d后仍保持稳定。驱油实验结果显示,CNT-TiO_(2)纳米流体提高采收率效果较好。

关键词：碳纳米管二氧化钛纳米复合材料纳米流体 Pickering乳液提高采收率

Hydroxyapatite-containing PEO-coating design for biodegradable Mg-0.8Ca alloy: Formation and corrosion behaviour

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Journal of Magnesium and Alloys 2023年第12期11卷 4468-4484页

作者： A.s.Gnedenkov s.L.sinebryukhov V.s.Filonina s.V.Gnedenkov Institute of Chemistry of FEB RAs 159 Pr.100-letiya VladivostokaVladivostok690022Russian Federation

In this study, the biocompatible protective coating was formed using plasma electrolytic oxidation(PEO) on bioresorbable Mg-0.8Ca alloy. The composition of the formed coating was studied using XRD, sEM-EDX analysis, and micro-Raman spectroscopy. The uniform distribution of hydroxyapatite over the thickness of protective PEO-layer was established. Using traditional(EIs, PDP, OCP) and local scanning electrochemical methods(sVET, sIET with H^(+)-selective microelectrode), the level of protective properties of PEO-layer in a biological environment(mammalian cell culture medium, MEM) was determined. It was established that modification of Mg-0.8Ca alloy surface by PEO contributes to a significant increase in the corrosion resistance of the surface layer, making it possible to control the process of material‘s biodegradation. The maximum local electrochemical activity was recorded after 72 h of testing, while for the uncoated sample,intense corrosion degradation was recorded in the first 12 min of exposure to the cell culture medium. Formation of the PEO-coating results in a twofold decrease in the corrosion current density(2.8·10^(-6)A cm^(-2)) and an increase in the impedance modulus measured at a low frequency(1.7·10^(4)Ω cm^(2)) in comparison with the uncoated material(9.5·10^(-6)A cm^(-2);8.1·10^(3)Ω cm^(2)). The mechanism of material bioresorption was established and a model for biodegradation process of Mg-0.8Ca alloy with hydroxyapatite-containing PEO-coating in MEM was proposed. Analysis of these results and comparing with others obtained by various scientific groups indicate the prospects for application of biocompatible PEO-coating on Mg-Ca alloy in implant surgery.

关键词： Magnesium-calcium alloy Biodegradation Implant surgery Plasma electrolytic oxidation Electrochemistry Minimum essential medium Hydroxyapatite

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction method.The red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission significantly.This improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

Identification and Prediction of Diabetic Macular Edema on Two-dimensional Fundus Images with Raphe Assessment and Deep Convolution Neural Networks

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Biomedical and Environmental sciences 2022年第12期35卷 1156-1160页

作者： s.Karkuzhali Department of Computer science and Engineering Mepco Schlenk Engineering CollegeSivakasiTamilnadu 626005India

Diabetes is a common disease that has affected more than 285 million individuals[1]. Diabetic macular edema(DME) is an ophthalmic disease that causes vision loss. Patients with diabetic retinopathy(DR)may also be affe... 详细信息

关键词： Diabetic edema Diabetes

Investigation of the Effect of Using Different Fly Ash on the Mechanical Properties in Cemented Paste Backfill

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Journal of Wuhan University of Technology(Materials science) 2022年第4期37卷 620-627页

作者： Tuylu s Department of Mining Engineering Istanbul University-CerrahpasaIstanbul34500Turkey

In the cemented paste backfill(CPB)method,which can also be used for fortification purposes in mines,different additive materials with pozzolanic properties can be employed as substitutes instead of cement that is the main binder.One of the most popular pozzolanic materials that can be employed instead of cement is fly ash,which is thermal power plant tailings.But the compositions of fly ash and tailings used in high amounts in the CPB method,as well as the chemical structures that these materials form by interacting with the cement binder,affect the mechanical properties of the material depending on time.In this study,fly ash with 4 different chemical compositions(TFA,sFA,YFA,and CFA)was used as a cement substitute in CPB.By substituting fly ash with different chemical compositions in different proportions,CPB samples were created and their strength was elucidated according to 28,56,and 90-day curing times.The results of the study revealed that TFA with the highest CaO/siO_(2) and sO_(3) ratios remained stable at the strength values of 6 MPa(total 9% binder)and 10 MPa(total 11% binder)in the long term.However,CFA with the lowest CaO/siO_(2),sO_(3),and the highest siO_(2)+Al_(2)O_(3)+Fe_(2)O_(3) ratios resulted in the greatest strength increase at a 20%substitution rate(11% of the total binder).Nevertheless,it was found that the sFA,which is in Class F,increased its strength in the early period based on the CaO rate.

关键词： tailings disposal cemented paste backfill fly ash chemical properties strength

一种新型能量检测方法降低认知无线电网络中的主用户仿真攻击

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Journal of Central south University 2022年第5期29卷 1510-1520页

作者： shriraghavan MADBUsHI M.s.s.RUKMINI st.Vincent Pallotti College of Engineering&Technology NagpurMaharashtraIndia Vignan’s Foundation for science Technology and ResearchVadlamudiGuntur(Dist.)India

扩展频谱效率最有前途的解决方案是认知无线电(CR)技术。这种扩展是通过允许未经许可的辅助用户(sUs)访问许可的频段来实现的,不存在对许可的主用户(PUs)的干扰。这种在频谱感知中对CR网络的使用会导致脆弱的攻击,如主用户仿真(PUE)攻击... 详细信息

扩展频谱效率最有前途的解决方案是认知无线电(CR)技术。这种扩展是通过允许未经许可的辅助用户(sUs)访问许可的频段来实现的,不存在对许可的主用户(PUs)的干扰。这种在频谱感知中对CR网络的使用会导致脆弱的攻击,如主用户仿真(PUE)攻击,此时,PUs扮演了恶意用户的角色,不允许其他用户即使在他们不可用的情况下使用PUs通道。在传统的单阈值能量检测算法的基础上,在CR网络中建立一种改进的双阈值能量检测器,对检测概率、漏检概率、误报概率及其相互关系进行检测分析。提出一种改进的双阈值能量检测协同频谱传感技术,以缓解对主要用户的攻击。并对所提出的方法与现有的不考虑提示攻击的能量检测频谱传感方法基于性能方面进行对比评价。在MATLAB的仿真结果表明,所提出的能量检测协同频谱传感技术性能出色,显著减轻了对主用户的攻击。

关键词：认知无线电能量检测频谱检测检测率误报率漏检率

Physico-mechanical characteristics of bast fibres of sesamum indicum and sesamum radiatum for bioprospecting

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Journal of Bioresources and Bioproducts 2022年第4期7卷 306-319页

作者： Ancy s Watson suhara Beevy s Department of Botany University of KeralaThiruvananthapuram 695581KeralaIndia

Natural fibres are renewable,inexpensive and biodegradable sources of sustainable materials from plants or animals.Bast fibres,as the notable natural fibres,are gathered from the outer cell layers of the stem of plant.Mature and young bast fibres from two species of sesamum,namely sesamum indicum L.and s.radiatum schumach.&Thonn.were extracted through traditional water retting technique and analyzed for their physical,mechanical and chemical attributes.Anatomical studies revealed polygon shaped phloem(bast fibre)cells with small lumen were similar to jute,in terms of architecture,and bagasse,in terms of lumen size.Upon extraction and subsequent drying,the young stems of s.radiatum were found to yield more bast fibres by mass compared with the rest of the sesamum samples,that was,0.59 g(dry weight)of bast fibres from 100 g(fresh weight)of stem.According to stereo microscopic images,the mature s.radiatum fibres had rougher edges than the rest.Both s.indicum and s.radiatum fibre surfaces also seemed to have pores,according to scanning electron microscopy(sEM)images.The porosity appeared to get more pronounced as the plants got older.The sesamum bast fibres were also found to be extremely hydrophilic with a high-water retention value.The fibres obtained from s.radiatum were determined to be suitable for the textile industry due to their light colour,ideal diameter and length,and water-holding capacity that matched the requirements of fabric manufacturing.Even in the absence of a mordant,the mature fibres showed a significant degree and evenness of Alizarin dye attachment,which might be correlated to the increase in fibre surface roughness with fibre maturity.These fibres were also discovered to be comparable with jute in terms of phloem cell shape(polygonal),diameter(13-15 m),tenacity(12.86-32.54 gf/(g·km-1)),and linear density(2.5-3.3 g/km).It suggested that they might find industrial applications if further research were to be done.

关键词： sesamum Bast fibre Textile Tensile strength Dyeing sustainability