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Health Systems Strengthening to Tackle the Global Burden of Pediatric and Congenital Heart Disease: A Diagonal Approach
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作者 Dominique Vervoort Amy Verstappen +2 位作者 Sreehari Madhavankutty Nair Chong Chin Eu Bistra Zheleva 《Congenital Heart Disease》 SCIE 2024年第2期131-138,共8页
1 Background Congenital heart disease(CHD)is the most common major congenital anomaly,affecting approximately one in every 100 live births[1].Among congenital anomalies,66%of preventable deaths are due to CHD,and 58%o... 1 Background Congenital heart disease(CHD)is the most common major congenital anomaly,affecting approximately one in every 100 live births[1].Among congenital anomalies,66%of preventable deaths are due to CHD,and 58%of the avertable morbidity and mortality due to congenital anomalies would result from scaling congenital heart surgery services[2].Every year,nearly 300,000 children and adults die from CHD,the majority of whom live in low-and middle-income countries(LMICs)[3].Approximately 49%of all individuals with CHD will require surgical or interventional care at some point in their lifetime[4];as a result of advances in access to and the delivery of such services,over 95%of children born with CHD in high-income countries now live into adulthood[3].Here,adults have surpassed children in the number of CHD cases at a ratio of 2:1[5]. 展开更多
关键词 Congenital heart disease pediatric heart disease global health health systems health policy
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Prediction models of burst strength degradation for casing with considerations of both wear and corrosion 被引量:1
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作者 Jie-Li Wang Wen-Jun Huang De-Li Gao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期458-474,共17页
Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep wells.This paper aims to predict the casing burst strength with considerations of both wear and corrosion... Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep wells.This paper aims to predict the casing burst strength with considerations of both wear and corrosion.Firstly,the crescent wear shape is simplified into three categories according to common mathematical models.Then,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are obtained.Secondly,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are obtained.At last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is obtained.The results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth growth.The accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded casing.The burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation. 展开更多
关键词 Deep well Casing integrity Casing wear Casing corrosion Burst strength
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Assessment of compressive strength of jet grouting by machine learning 被引量:1
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作者 Esteban Diaz Edgar Leonardo Salamanca-Medina Roberto Tomas 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期102-111,共10页
Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction projects.The high dispersion in the prope... Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction projects.The high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test fields.The present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research papers.The selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive strength.Despite the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing works.Consequently,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns. 展开更多
关键词 Jet grouting Ground improvement Compressive strength Machine learning
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The influence of resistance exercise training prescription variables on skeletal muscle mass,strength,and physical function in healthy adults:An umbrella review 被引量:1
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作者 Jonathan C.Mcleod Brad S.Currier +1 位作者 Caroline V.Lowisz Stuart M.Phillips 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期47-60,共14页
Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following ... Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines,we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass(or its proxies),strength,and/or physical function in healthy adults aged>18 years.Results:We identified 44 systematic reviews that met our inclusion criteria.The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews;standardized effectiveness statements were generated.We found that RT was consistently a potent stimulus for increasing skeletal muscle mass(4/4 reviews provide some or sufficient evidence),strength(4/6 reviews provided some or sufficient evidence),and physical function(1/1 review provided some evidence).RT load(6/8 reviews provided some or sufficient evidence),weekly frequency(2/4 reviews provided some or sufficient evidence),volume(3/7 reviews provided some or sufficient evidence),and exercise order(1/1 review provided some evidence)impacted RT-induced increases in muscular strength.We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass,while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass.There was insufficient evidence to conclude that time of day,periodization,inter-set rest,set configuration,set end point,contraction velocity/time under tension,or exercise order(only pertaining to hypertrophy)influenced skeletal muscle adaptations.A paucity of data limited insights into the impact of RT prescription variables on physical function.Conclusion:Overall,RT increased muscle mass,strength,and physical function compared to no exercise.RT intensity(load)and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy.RT volume(number of sets)influenced muscular strength and hypertrophy. 展开更多
关键词 HYPERTROPHY Resistance training Resistance training prescription variables strength Umbrella review
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Left bundle branch pacing vs biventricular pacing in heart failure patients with left bundle branch block:A systematic review and meta-analysis 被引量:1
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作者 Farah Yasmin Abdul Moeed +7 位作者 Rohan Kumar Ochani Hamna Raheel Malik Ali Ehtsham Awan Ayesha Liaquat Arisha Saleem Muhammad Aamir Nael Hawwa Salim Surani 《World Journal of Cardiology》 2024年第1期40-48,共9页
BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore... BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore the validity of electromechanical resynchronization,clinical and echocardiographic response of LBBP-CRT.METHODS Systematic review and Meta-analysis were conducted in accordance with the standard guidelines as mentioned in detail in the methodology section.RESULTS In our analysis,the success rate of LBBP-CRT was determined to be 91.1%.LBBP CRT significantly shortened QRS duration,with significant improvement in echocardiographic parameters,including left ventricular ejection fraction,left ventricular end-diastolic diameter and left ventricular end-systolic diameter in comparison with BiVP-CRT.CONCLUSION A significant reduction in New York Heart Association class and B-type natriuretic peptide levels was also observed in the LBBP-CRT group vs BiVP-CRT group.Lastly,the LBBP-CRT cohort had a reduced pacing threshold at follow-up as compared to BiVP-CRT. 展开更多
关键词 Left bundle branch pacing Biventricular pacing QRS duration Left ventricular ejection fraction heart failure
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Investigation of anisotropic strength criteria for layered rock mass
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作者 Shuling Huang Jinxin Zhang +4 位作者 Xiuli Ding Chuanqing Zhang Gang Han Guoqi Yu Lulu Qu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1289-1304,共16页
Layered rock mass is a type of engineering rock mass with sound mechanical anisotropy,which is generally unfavorable to the stability of underground works.To investigate the strength anisotropy of layered rock,the Moh... Layered rock mass is a type of engineering rock mass with sound mechanical anisotropy,which is generally unfavorable to the stability of underground works.To investigate the strength anisotropy of layered rock,the Mohr-Coulomb and Hoek-Brown criteria are introduced to establish the two transverse isotropic strength criteria based on Jaeger's single weak plane theory and maximum axial strain theory,and parameter determination methods.Furthermore,the sensitivity of strength parameters(K 1,K 2,and K 3)that are used to characterize the anisotropy strength of non-sliding failure involved in the strength criteria and confining pressure are investigated.The results demonstrate that strength parameters K 1 and K 2 affect the strength of layered rock samples at all bedding angles except for the bedding angle of 90°and the angle range that can cause the shear sliding failure along the bedding plane.The strength of samples at any bedding angle decreases with increasing K 1,whereas the opposite is for K 2.Except for bedding angles of 0°and 90°and the bedding angle range that can cause the shear sliding along the bedding plane,K 3 has an impact on the strength of rock samples with other bedding angles that the specimens'strength increases with increase of K 3.In addition,the strength of the rock sample increases as confining pressure rises.Furthermore,the uniaxial and triaxial tests of chlorite schist samples were carried out to verify and evaluate the strength criteria proposed in the paper.It shows that the predicted strength is in good agreement with the experimental results.To test the applicability of the strength criterion,the strength data of several types of rock in the literature are compared.Finally,a comparison is made between the fitting effects of the two strength criteria and other available criteria for layered rocks. 展开更多
关键词 Layered rock strength anisotropy strength criterion Experimental verification
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Uniaxial Compressive Strength Prediction for Rock Material in Deep Mine Using Boosting-Based Machine Learning Methods and Optimization Algorithms
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作者 Junjie Zhao Diyuan Li +1 位作者 Jingtai Jiang Pingkuang Luo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期275-304,共30页
Traditional laboratory tests for measuring rock uniaxial compressive strength(UCS)are tedious and timeconsuming.There is a pressing need for more effective methods to determine rock UCS,especially in deep mining envir... Traditional laboratory tests for measuring rock uniaxial compressive strength(UCS)are tedious and timeconsuming.There is a pressing need for more effective methods to determine rock UCS,especially in deep mining environments under high in-situ stress.Thus,this study aims to develop an advanced model for predicting the UCS of rockmaterial in deepmining environments by combining three boosting-basedmachine learning methods with four optimization algorithms.For this purpose,the Lead-Zinc mine in Southwest China is considered as the case study.Rock density,P-wave velocity,and point load strength index are used as input variables,and UCS is regarded as the output.Subsequently,twelve hybrid predictive models are obtained.Root mean square error(RMSE),mean absolute error(MAE),coefficient of determination(R2),and the proportion of the mean absolute percentage error less than 20%(A-20)are selected as the evaluation metrics.Experimental results showed that the hybridmodel consisting of the extreme gradient boostingmethod and the artificial bee colony algorithm(XGBoost-ABC)achieved satisfactory results on the training dataset and exhibited the best generalization performance on the testing dataset.The values of R2,A-20,RMSE,and MAE on the training dataset are 0.98,1.0,3.11 MPa,and 2.23MPa,respectively.The highest values of R2 and A-20(0.93 and 0.96),and the smallest RMSE and MAE values of 4.78 MPa and 3.76MPa,are observed on the testing dataset.The proposed hybrid model can be considered a reliable and effective method for predicting rock UCS in deep mines. 展开更多
关键词 Uniaxial compression strength strength prediction machine learning optimization algorithm
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Estimating shear strength of high-level pillars supported with cemented backfilling using the HoekeBrown strength criterion
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作者 Kaizong Xia Congxin Chen +3 位作者 Xiumin Liu Yue Wang Xuanting Liu Jiahao Yuan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期454-469,共16页
Deep metal mines are often mined using the high-level pillars with subsequent cementation backfilling(HLSCB)mining method.At the design stage,it is therefore important to have a reasonable method for determining the s... Deep metal mines are often mined using the high-level pillars with subsequent cementation backfilling(HLSCB)mining method.At the design stage,it is therefore important to have a reasonable method for determining the shear strength of the high-level pillars(i.e.cohesion and internal friction angle)when they are supported by cemented backfilling.In this study,a formula was derived for the upper limit of the confining pressure σ3max on a high-level pillar supported by cemented backfilling in a deep metal mine.A new method of estimating the shear strength of such pillars was then proposed based on the Hoek eBrown failure criterion.Our analysis indicates that the horizontal stress σhh acting on the cemented backfill pillar can be simplified by expressing it as a constant value.A reasonable and effective value for σ3max can then be determined.The value of s3max predicted using the proposed method is generally less than 3 MPa.Within this range,the shear strength of the high-level pillar is accurately calculated using the equivalent MohreCoulomb theory.The proposed method can effectively avoid the calculation of inaccurate shear strength values for the high-level pillars when the original HoekeBrown criterion is used in the presence of large confining pressures,i.e.the situation in which the cohesion value is too large and the friction angle is too small can effectively be avoided.The proposed method is applied to a deep metal mine in China that is being excavated using the HLSCB method.The shear strength parameters of the high-level pillars obtained using the proposed method were input in the numerical simulations.The numerical results show that the recommended level heights and sizes of the high-level pillars and rooms in the mine are rational. 展开更多
关键词 Deep metal mines High-level pillars HoekeBrown strength criterion Cemented backfilling Confining pressure Shear strength
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HEART五步沟通模式对乳腺癌化疗患者心理弹性及癌因性疲乏的影响
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作者 孔大英 杜宜华 《当代护士(上旬刊)》 2024年第5期59-62,共4页
目的探讨HEART五步沟通模式对乳腺癌化疗患者心理弹性及癌因性疲乏的影响。方法本研究为随机单盲对照试验,采用方便抽样法,选取无锡市人民医院肿瘤科于2022年1月—12月收治的84例乳腺癌化疗患者为研究对象,采用随机数字表法将其分为对... 目的探讨HEART五步沟通模式对乳腺癌化疗患者心理弹性及癌因性疲乏的影响。方法本研究为随机单盲对照试验,采用方便抽样法,选取无锡市人民医院肿瘤科于2022年1月—12月收治的84例乳腺癌化疗患者为研究对象,采用随机数字表法将其分为对照组与观察组,每组各42例。为避免组间沾染,将对照组安排至肿瘤一科,实施常规化疗护理;将观察组安排至肿瘤二科,在常规化疗护理的基础上实施HEART五步沟通模式。两组患者均化疗4个周期,比较两组患者首次化疗入院当天(干预前)、末次化疗出院当天(干预后)的心理弹性及癌因性疲乏。结果干预后,观察组的心理弹性评分明显高于对照组(P<0.05);观察组的癌因性疲乏评分明显低于对照组(P<0.05)。结论对乳腺癌化疗患者在常规化疗护理的基础上实施HEART五步沟通模式,能够明显提高患者的心理弹性,缓解患者的癌因性疲乏症状。 展开更多
关键词 heart五步沟通模式 乳腺癌化疗 心理弹性 癌因性疲乏
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A simple atomization approach enables monolayer dispersion of nano graphenes in cementitious composites with excellent strength gains
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作者 Nanxi Dang Rijiao Yang +4 位作者 Chengji Xu Yu Peng Qiang Zeng Weijian Zhao Zhidong Zhang 《Nano Materials Science》 EI CAS CSCD 2024年第2期211-222,共12页
Carbon nano additives(CNAs)are critical to achieving the unique properties of functionalized composites,however,controlling the dispersion of CNAs in material matrix is always a challenging task.In this study,a simple... Carbon nano additives(CNAs)are critical to achieving the unique properties of functionalized composites,however,controlling the dispersion of CNAs in material matrix is always a challenging task.In this study,a simple atomization approach was successfully developed to promote the dispersion efficiency of graphene nanoplatelets(GNPs)in cement composites.This atomization approach can be integrated with the direct,indirect and combined ultrasonic stirrings in a homemade automatic stirring-atomization device.Mechanical and microstructure tests were performed on hardened cement pastes blended with GNPs in different stirring and mixing approaches.Results show that the direct ultrasonic stirrings enabled more homogeneous dispersions of GNP particles with a smaller size for a longer duration.The atomized droplets with the mean size of~100μm largely mitigated GNPs’agglomerations.Monolayer GNPs were observed in the cement matrix with the strength gain by up to 54%,and the total porosity decrease by 21%in 0.3 wt%GNPs dosage.The greatly enhanced dispersion efficiency of GNPs in cement also raised the cement hydration.This work provides an effective and manpower saving technique toward dispersing CNAs in engineering materials with great industrialization prospects. 展开更多
关键词 NANOMATERIALS DISPERSION ATOMIZATION strength Microstructure
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Machine Learning-Based Intelligent Auscultation Techniques in Congenital Heart Disease:Application and Development
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作者 Yang Wang Xun Yang +6 位作者 Mingtang Ye Yuhang Zhao Runsen Chen Min Da Zhiqi Wang Xuming Mo Jirong Qi 《Congenital Heart Disease》 SCIE 2024年第2期219-231,共13页
Congenital heart disease(CHD),the most prevalent congenital ailment,has seen advancements in the“dual indi-cator”screening program.This facilitates the early-stage diagnosis and treatment of children with CHD,subse-... Congenital heart disease(CHD),the most prevalent congenital ailment,has seen advancements in the“dual indi-cator”screening program.This facilitates the early-stage diagnosis and treatment of children with CHD,subse-quently enhancing their survival rates.While cardiac auscultation offers an objective reflection of cardiac abnormalities and function,its evaluation is significantly influenced by personal experience and external factors,rendering it susceptible to misdiagnosis and omission.In recent years,continuous progress in artificial intelli-gence(AI)has enabled the digital acquisition,storage,and analysis of heart sound signals,paving the way for intelligent CHD auscultation-assisted diagnostic technology.Although there has been a surge in studies based on machine learning(ML)within CHD auscultation and diagnostic technology,most remain in the algorithmic research phase,relying on the implementation of specific datasets that still await verification in the clinical envir-onment.This paper provides an overview of the current stage of AI-assisted cardiac sounds(CS)auscultation technology,outlining the applications and limitations of AI auscultation technology in the CHD domain.The aim is to foster further development and refinement of AI auscultation technology for enhanced applications in CHD. 展开更多
关键词 Congenital heart disease heart sound auscultation artificial intelligence machine learning
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Epidemiological, Clinical, Therapeutic, and Evolutionary Aspects of Heart Failure in the Medical Department at Gao Regional Hospital
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作者 Coulibaly Alhousseny Dollo Ibrahim +10 位作者 Guindo Hamadoun Sidibé Lamine Mariko Souleymane Traoré Bassirima Dao Karim Guindo Ibrahim Togo Mamadou Sidibé Samba Sangaré Ibrahima Ba Hamidou Oumar Ichiaka Menta 《World Journal of Cardiovascular Diseases》 CAS 2024年第5期309-321,共13页
Introduction: Heart failure is a major public health pandemic, particularly in Africa, where its prevalence continues to increase. In northern Mali, few data exist, hence the interest of this study with the objective ... Introduction: Heart failure is a major public health pandemic, particularly in Africa, where its prevalence continues to increase. In northern Mali, few data exist, hence the interest of this study with the objective of studying the epidemiological, clinical and therapeutic and evolutionary aspects of Heart failure at the regional hospital of Gao. Patients and Methods: This was a cross-sectional, descriptive study that took place from July 2022 to June 2023 in the medical department at Gao Hospital. Results: The hospital prevalence of heart failure was 44.1%. The mean age was 47.30 ± 20 years (range: 16-88). Hypertension was the most common with 46.1%, followed by a sedentary lifestyle, and diabetes with 18.2% and 8.3% respectively;NYHA stage III-IV dyspnea was found in 83.9%. Reduced EF heart failure was present in 110 patients (76.9%), seventeen cases with moderately reduced EF (11.9%) and sixteen patients had preserved EF (11.2%). Global heart failure was the dominant (91.6%). The main etiologies of heart failure were dominated by hypertensive heart disease in 46 patients (32.2%), followed by postpartum cardiomyopathy with 43 cases (30.1%), primary dilated cardiomyopathy in 18 patients (12.6%), ischemic heart disease in 16 patients with 11.2%. Seven cases of valvular heart disease, or 4.9%. The evolution was favorable under treatment in 104 patients or 72.7%. In-hospital mortality was 14.7%. Conclusion: Heart failure is a common condition in sub-Saharan Africa, particularly in our country. 展开更多
关键词 heart Failure Epidemioclinical PROGRESSIVE Gao Hospital
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Iron and Heart Failure: Current Concepts and Emerging Pharmacological Paradigms
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作者 Maria Rosaria De Pascale Maria Beatrice Rondinelli +5 位作者 Flora Ascione Vincenzo Maffei Chiara Di Lorenzo Sarah Scagliarini Raffaella Faraonio Antonio Faiella 《World Journal of Cardiovascular Diseases》 CAS 2024年第4期195-216,共22页
Background: Emerging evidence has recognized that anemia and iron deficiency are recurrent comorbidities in chronic heart failure (HF) and several trials have established that iron administration improves myocardial a... Background: Emerging evidence has recognized that anemia and iron deficiency are recurrent comorbidities in chronic heart failure (HF) and several trials have established that iron administration improves myocardial asset and clinical scenario in HF. Purpose: Recent acquisitions suggest that iron deficiency represents a concrete bias in the pathogenetic mechanism of chronic HF, so we have investigated the putative role of the hepcidin/ferroportin axis in the cardiovascular setting to advocate novel pharmacological and clinical approaches. Methods: Here, after an excursus on iron metabolism, we first reviewed the ongoing studies on novel iron targeted compounds. Then, we summarize large clinical interventional studies conducted on patient suffering from iron deficiency and HF which have tested the effects of drugging iron regard QoL, hospitalizations and cardiovascular death. Results: Novel compounds such as hepcidin agonist (PTG 300), synthetic human hepcidin (LJPC-401) and anti FPN (Vamifeport) are ongoing in iron overloaded patients, while the hepcidin blocker (PRS-080) is under investigation in anemic patients. Noteworthy, novel insights could arise from the results of a Phase IV interventional study regarding the modification of hepcidin pathway in a large cohort of HF patients (n = 1992) by sodium glucose cotransporter 2 inhibitors. To date, several studies highlight the beneficial effect of iron administration in cardiovascular setting and latest evidences consider hepcidin level as a novel biomarker of cardiac injury and atherosclerosis. Conclusions: We advocate that data from ongoing studies will suggest novel iron targeted therapies for diagnosis, prognosis and therapy transferable in selected heart failed patients. 展开更多
关键词 heart Failure IRON ANEMIA Iron Deficiency HEPCIDIN
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Retrospective and prospective review of the generalized nonlinear strength theory for geomaterials
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作者 Shunchuan Wu Jiaxin Wang +3 位作者 Shihuai Zhang Shigui Huang Lei Xia Qianping Zhao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1767-1787,共21页
Strength theory is the basic theory for calculating and designing the strength of engineering materials in civil,hydraulic,mechanical,aerospace,military,and other engineering disciplines.Therefore,the comprehensive st... Strength theory is the basic theory for calculating and designing the strength of engineering materials in civil,hydraulic,mechanical,aerospace,military,and other engineering disciplines.Therefore,the comprehensive study of the generalized nonlinear strength theory(GNST)of geomaterials has significance for the construction of engineering rock strength.This paper reviews the GNST of geomaterials to demonstrate the research status of nonlinear strength characteristics of geomaterials under complex stress paths.First,it systematically summarizes the research progress of GNST(classical and empirical criteria).Then,the latest research the authors conducted over the past five years on the GNST is introduced,and a generalized three-dimensional(3D)nonlinear Hoek‒Brown(HB)criterion(NGHB criterion)is proposed for practical applications.This criterion can be degenerated into the existing three modified HB criteria and has a better prediction performance.The strength prediction errors for six rocks and two in-situ rock masses are 2.0724%-3.5091%and 1.0144%-3.2321%,respectively.Finally,the development and outlook of the GNST are expounded,and a new topic about the building strength index of rock mass and determining the strength of in-situ engineering rock mass is proposed.The summarization of the GNST provides theoretical traceability and optimization for constructing in-situ engineering rock mass strength. 展开更多
关键词 rock mechanics rock mass strength strength theory failure criterion Hoek-Brown criterion intermediate principal stress deviatoric plane smoothness and convexity
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Adhesion strength of tetrahydrofuran hydrates is dictated by substrate stiffness
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作者 Yan-Wen Lin Tong Li +4 位作者 Yi Zhang Wei-Wei Yan Xiao-Ming Chen Zhi-Sen Zhang Jian-Yang Wu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期667-673,共7页
Understanding the hydrate adhesion is important to tackling hydrate accretion in petro-pipelines.Herein,the relationship between the Tetrahydrofuran(THF)hydrate adhesion strength(AS)and surface stiffness on elastic co... Understanding the hydrate adhesion is important to tackling hydrate accretion in petro-pipelines.Herein,the relationship between the Tetrahydrofuran(THF)hydrate adhesion strength(AS)and surface stiffness on elastic coatings is systemically examined by experimental shear force measurements and theoretical methods.The mechanical factor-elastic modulus of the coatings greatly dictates the hydrate AS,which is explained by the adhesion mechanics theory,beyond the usual factors such as wettability and structural roughness.Moreover,the hydrate AS increases with reducing the thickness of the elastic coatings,resulted from the decrease of the apparent surface elastic modulus.The effect of critical thickness for the elastic materials with variable elastic modulus on the hydrate AS is also revealed.This study provides deep perspectives on the regulation of the hydrate AS by the elastic modulus of elastic materials,which is of significance to design anti-hydrate surfaces for mitigation of hydrate accretion in petro-pipelines. 展开更多
关键词 HYDRATE Adhesion strength Elastic modulus COATINGS
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Long-Term Mortality of Children with Congenital Heart Disease Admitted to the Departmental University Hospital of Borgou/Alibori from 2011 to 2022
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作者 Serge Hugues Mahougnon Dohou Nicolas Hamondji Amegan +3 位作者 Ahmad Ibrahim Gérard Médétinmè Kpanidja Chabi Olaniran Alphonse Biaou Houétondji Léopold Codjo 《World Journal of Cardiovascular Diseases》 CAS 2024年第3期166-186,共21页
Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitte... Background: Congenital heart disease is a public health issue due to its incidence and mortality rate. The aim of this study was to investigate the long-term mortality of children with congenital heart disease admitted to the Departmental University Hospital of Borgou/Alibori (CHUD-B/A) from 2011 to 2022. Methods: This descriptive longitudinal study with analytical aims covered 11 years (April 1, 2011 to December 31, 2022). It consisted of a review of the records of children under 15 years of age with echocardiographically confirmed congenital heart disease. This was followed by an interview with the parents to assess the children’s current condition. Data were entered using Kobocollect software and analyzed using R Studio 4.2.2. software. Results: A total of 143 complete files were retained. The median age at diagnosis was 14 months (IIQ: Q1 = 4;Q3 = 60) with a range of 2 days and 175 months, and the sex-ratio (M/F) was 0.96. Left-to-right shunts were the most frequent cardiopathy group (62.9%). Only 35 children (24.5%) benefited from restorative treatment. The mortality rate was 31.5%. Median survival under the maximum bias assumption was 114 months and 216 months under the assumption of minimum bias. Survival was significantly better in children with right-to-left shunts (p = 0.0049) under the assumption of minimum bias. The death risk factors were: age at diagnosis less than 12 months (aHR = 7.58;95% CI = 3.36 - 17.24;p Conclusion: The long-term mortality of congenital heart disease is high and favoured by the absence of restorative treatment. Local correction of congenital heart disease and medical follow-up will help to reduce this mortality. 展开更多
关键词 Congenital heart Disease LONG-TERM MORTALITY Parakou Risk Factors
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Contribution of Stress Testing to the Management of Ischemic Heart Disease in Mali
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作者 Youssouf Camara Hamidou Oumar Ba +7 位作者 Ibrahima Sangaré Boubacar Sonfo Coumba Adiaratou Thiam Mahamadou Sékou Diakité Koniba Diarra Karamba Touré Massama Konaté Ichaka Menta 《World Journal of Cardiovascular Diseases》 CAS 2024年第2期77-87,共11页
Introduction: Exercise stress testing (on a treadmill or ergometer bicycle) is an important test in cardiology for diagnosing myocardial ischemia. This test in Mali is still in its beginning compared to other countrie... Introduction: Exercise stress testing (on a treadmill or ergometer bicycle) is an important test in cardiology for diagnosing myocardial ischemia. This test in Mali is still in its beginning compared to other countries in the sub-region. The lack of data in Mali prompted this study, which aimed to evaluate the indications of this activity and its diagnostic contribution to cardiology in Mali. Materials and Methods: This was a retrospective, descriptive study. The study was conducted at the “TOUCAM” medical clinic in Kati based on the analysis of stress test reports between January 2016 and August 2022. Result: During the study period, we documented 73 patients who underwent exercise testing on a bicycle ergometer for suspected coronary heart disease. The mean age of our patients was 47.5 ± 13.8 years (14 and 79 years). Males accounted for the majority (78.1%). The sex ratio is 3.5. More than half of our patients were overweight or obese (77.1%). Hypertension and diabetes affected 52.1% and 25.8% of patients, respectively. 20.8% of patients had coronary artery disease. renin-angiotensin-aldosterone system blockers (56.8%) and beta-blockers (51.3%). The main indications were chest pain (63.0%) and ischemia detection (15.1%). A modified STEEP protocol was used. The majority of our patients (71.2%) achieved at least 85% of their maximum theoretical heart rate. The main reason for the termination of the study was fatigue (57.3%). The average duration was 11.3 ± 4.2 minutes. 24.7% thought the stress tests were positive and 17.8% thought they were controversial. Conclusion: This study demonstrates the importance of stress testing in the diagnosis and treatment of ischemic heart disease, especially in settings where we have very limited access to coronary angiography. 展开更多
关键词 Stress Test Ischemic heart Disease MALI
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Interest of Cardiac Rehabilitation in Patients with Heart Disease in a Cardiology Department in Senegal
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作者 Awa Ba-Diop Abdou Khadir Sow +7 位作者 Rim Mohamed Khaled Mor Diaw Mame Saloum Coly Fulgence Abdou Faye Amadou Ndiadé Bamba Gaye Abdoulaye Ba Abdoulaye Samb 《World Journal of Cardiovascular Diseases》 CAS 2024年第4期217-227,共11页
Cardiac rehabilitation helps improve the prognosis and quality of life for patients with heart disease. To show its interest in the African context, in the management of heart disease, a prospective study was carried ... Cardiac rehabilitation helps improve the prognosis and quality of life for patients with heart disease. To show its interest in the African context, in the management of heart disease, a prospective study was carried out. Its objective was to evaluate the effects of physical rehabilitation on cardiac function. Methods: Patients were evaluated at the beginning and at the end of cardiovascular rehabilitation by cardiovascular, biological, and echocardiographic parameters including the size of the heart chambers, the kinetics of the walls, and the systolic function of the ventricles. Results: The study involved 12 patients, 67% of whom were men. After cardiac rehabilitation, the mean hemodynamic constants had not been significantly modified. However, a significant decrease in Total-Cholesterol, LDL-Cholesterol and triglyceride levels was noted. Mean fasting blood sugar decreased from 1.25 ± 0.48 g/L to 0.92 ± 0.18 g/L and glycated hemoglobin from 7.72% ± 0.01% to 6.45% ± 0.008%. The echocardiographic parameters studied showed an improvement in the dilation of the heart chambers in 8.33% of the patients, the normalization of the ejection fraction of the left ventricle in 16% patients, the improvement of the kinetic disorders in 16% of patients and recovery of right ventricular systolic function in all patients. Conclusion: Cardiac rehabilitation as a secondary preventive measure for cardiovascular disease has contributed significantly to improving the clinico-biological parameters of the disease. 展开更多
关键词 Cardiac Rehabilitation heart Disease Cardiovascular Disease
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Estradiol increases cortical and trabecular bone accrual and bone strength in an adolescent male-to-female mouse model of gender-affirming hormone therapy
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作者 Tian Nie Varun S.Venkatesh +7 位作者 Suzanne Golub Kathryn S.Stok Haniyeh Hemmatian Reena Desai David J.Handelsman Jeffrey D.Zajac Mathis Grossmann Rachel A.Davey 《Bone Research》 SCIE CAS CSCD 2024年第1期95-106,共12页
The effects of gender-affirming hormone therapy on the skeletal integrity and fracture risk in transitioning adolescent trans girls are unknown.To address this knowledge gap,we developed a mouse model to simulate male... The effects of gender-affirming hormone therapy on the skeletal integrity and fracture risk in transitioning adolescent trans girls are unknown.To address this knowledge gap,we developed a mouse model to simulate male-to-female transition in human adolescents in whom puberty is first arrested by using gonadotrophin-releasing hormone analogs with subsequent estradiol treatment.Puberty was suppressed by orchidectomy in male mice at 5 weeks of age.At 3 weeks post-surgery,male-to-female mice were treated with a high dose of estradiol(~0.85 mg)by intraperitoneal silastic implantation for 12 weeks.Controls included intact and orchidectomized males at 3 weeks post-surgery,vehicle-treated intact males,intact females and orchidectomized males at 12 weeks post-treatment.Compared to male controls,orchidectomized males exhibited decreased peak bone mass accrual and a decreased maximal force the bone could withstand prior to fracture.Estradiol treatment in orchidectomized male-to-female mice compared to mice in all control groups was associated with an increased cortical thickness in the mid-diaphysis,while the periosteal circumference increased to a level that was intermediate between intact male and female controls,resulting in increased maximal force and stiffness.In trabecular bone,estradiol treatment increased newly formed trabeculae arising from the growth plate as well as mineralizing surface/bone surface and bone formation rate,consistent with the anabolic action of estradiol on osteoblast proliferation.These data support the concept that skeletal integrity can be preserved and that long-term fractures may be prevented in trans girls treated with GnRHa and a sufficiently high dose of GAHT.Further study is needed to identify an optimal dose of estradiol that protects the bone without adverse side effects. 展开更多
关键词 TREATMENT TREATMENT strength
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Heart Failure-Like Reaction Is Likely Involved in the Feeding Behaviour of Blood-Sucking Leeches
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作者 Li Yang Jiao Shu +4 位作者 Xiao Wang Wei Yu Debin Wang Zichao Liu Bin Wang 《Advances in Bioscience and Biotechnology》 CAS 2024年第1期52-69,共18页
Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between ... Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between leech and host, the body transcriptomes of hunger and fed blood-sucking Poecilobdella javanica, Haemadipsa cavatuses, and Hirudo nipponia leeches were obtained by RNA sequencing, after comparison, a stratified unigenes group was obtained, which closely correlated to body distension. In the group, Rfamide receptor decreased significantly (P < 0.05) while serotonin receptor increased significantly (P < 0.05). Moreover, four KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including cardiac muscle contraction, complement and coagulation cascades, renin-angiotensin system, and hypertrophic cardiomyopathy were significantly enriched. The unigenes annotation, neuroregulators correlation analysis and induced function of the KEGG pathways, were consistently supported the same result as: vasoconstriction and systole reaction enhance in hunger leeches and vice versa vasodilation and diastole increase in fed leeches, meanwhile, Interspecific comparison and correlative analyses of physiological function showed that the strongest reaction of induced heart failure from four KEGG occur in strongest reaction of systole in hungry P. javanica and in strongest reaction of diastole in fed H. nipponia. Overall, heart failure is likely a physiological function involved in feeding behaviour. 展开更多
关键词 Blood-Sucking Leeches Transcriptomic Analysis heart Failure Feeding Behaviour
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