以我国某钢厂120 t LF精炼炉为研究对象,通过建立由冶炼机理模型和XGBoost模型相结合的混合模型,预测LF精炼过程中的钢水成分并进行实际应用。结果表明,模型预测终点碳、硅、锰、铝等元素均处于内控范围内,并平均减少了每炉钢取样工序0....以我国某钢厂120 t LF精炼炉为研究对象,通过建立由冶炼机理模型和XGBoost模型相结合的混合模型,预测LF精炼过程中的钢水成分并进行实际应用。结果表明,模型预测终点碳、硅、锰、铝等元素均处于内控范围内,并平均减少了每炉钢取样工序0.8次,提高了生产效率。展开更多
Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which ...Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ failure.Methods:Animals were divided into 3 groups,normal,thioacetamide(TAA,ALF model)and TAA+AGK2.Cultured L02 cells were divided into 5 groups,normal,TAA,TAA+mitofusin 2(MFN2)-siRNA,TAA+AGK2,and TAA+AGK2+MFN2-siRNA groups.The liver histology was evaluated with hematoxylin and eosin staining,inositol-requiring enzyme 1(IRE1),activating transcription factor 6β(ATF6β),protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)and phosphorylated-PERK(p-PERK).C/EBP homologous protein(CHOP),reactive oxygen species(ROS),MFN2 and glutathione peroxidase 4(GPX4)were measured with Western blotting,and cell viability and liver chemistry were also measured.Mitochondriaassociated endoplasmic reticulum membranes(MAMs)were measured by immunofluorescence.Results:The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis,which were reduced by AGK2 pre-treatment.In comparison to the normal group,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+in the TAA-induced ALF model group were significantly increased,which were decreased by AGK2 pre-treatment.The levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group,which were enhanced by AGK2 pretreatment.Compared with the TAA-induced L02 cell,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA group.AGK2 pre-treatment decreased the apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 cell.Immunofluorescence observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced group in both mice and L02 cells.Conclusions:The data suggested that AGK2 pre-treatment had hepatoprotective role in TAA-induced ALF via upregulating the expression of MFN2 and then inhibiting PERK and ferroptosis pathway in ALF.展开更多
The devastating 2004 tsunamis that hit the southwestern coast of Thailand pose a serious threat to people along the coastal zone. A major aim for the tsunami hazard prediction is better prediction of the next tsunamis...The devastating 2004 tsunamis that hit the southwestern coast of Thailand pose a serious threat to people along the coastal zone. A major aim for the tsunami hazard prediction is better prediction of the next tsunamis and their impacts. In this paper, we present the first implications of recent slope failure events of the Andaman outer shelf and upper slope based on a new detailed bathymetric data and subbottom profiler records acquired during two cruises of the MASS project in 2006 and 2007. Morphometric analysis reveals a variety of anomalous features,including: three large plateaus surrounded by moats, ruggedness and unevenness of slope morphology, and two translational submarine landslides. Two submarine landslides are studied from the detailed bathymetric data and subbottom profiler record covering the upper slope of the Andaman Sea shelf break within Thai exclusive economic zone. Maximum approximated volumes of both displaced masses are 4.8×10~7 m~3 and 2.2×10~7 m~3.Considering the data, there is no evidence that landslides have been the sources for tsunami hazard potential in recent geological time. These prerequisites will allow better study of slope failure events in the area. Further investigation is required to better understand obvious geotectonic phenomena.展开更多
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
Only simplified two-dimensional model and a single failure mode are adopted to calculate the ultimate pullout capacity(UPC)of anchor cables in most previous research.This study focuses on a more comprehensive combinat...Only simplified two-dimensional model and a single failure mode are adopted to calculate the ultimate pullout capacity(UPC)of anchor cables in most previous research.This study focuses on a more comprehensive combination failure mode that consists of bond failure of an anchorage body and failure of an anchored rock mass.The three-dimensional ultimate pullout capacity of the anchor cables is calculated based on the Hoek-Brown failure criterion and variation analysis method.The numerical solution for the curvilinear function in fracture plane is obtained based on the finite difference theory,which more accurately reflects the failure state of the anchor cable,as opposed to that being assumed in advance.The results reveal that relying solely on a single failure mode for UPC calculations has limitations,as changes in parameter values not only directly impact the UPC value but also can alter the failure model and thus the calculation method.展开更多
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
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
In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock slopes.Especially for intermitt...In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock slopes.Especially for intermittently bedding jointed rock slopes,the correlation and difference in strength parameters between joints and rock bridges,along with the various failure modes and intermittency of rock bridges,contribute to the complexity of stepped failure modes and the unpredictability of failure regions.Based on the upper-bound limit analysis method and multi-sliders step-path failure mode,considering the shear and tensile failure of rock bridges and the weakened relationship between the strength parameters of rock bridges and jointed surfaces,by introducing the modified M-C failure criterion and the formula for calculating the energy consumption of tensile failure of rock bridges,two failure mechanisms are constructed to obtain the safety factor(F_(s))of intermittently jointed rock slopes.The sequential quadratic programming method is used to obtain the optimal upper-bound solution for F_(s).The influence of multiple key parameters(slope height H,horizontal distance L,Slope angleβ,shear strength parameters of the rock bridgeφr and cr,Dimensionless parameter u,weakening coefficients of the internal friction angle and cohesion between the rock bridges and joint surfaces Kφand Kc)on the stability analysis of intermittently jointed rock slopes under the shear failure mode of rock bridges as well as under the tensile failure mode is also explored.The reliability of the failure mechanisms is verified by comparative analysis with theoretical results,numerical results,and landslide cases,and the variation rules of F_(s)with each key parameter are obtained.The results show that F_(s) varies linearly withφr and cr of the rock bridge and with K_(φ)and K_(c),whereas F_(s)changes nonlinearly with H and L.In particular,with the increase in Kφand Kc,Fs increases by approximately 52.78%and 171.02%on average,respectively.For rock bridge tensile failure,F_(s) shows a nonlinearly positive correlation withφr,cr,Kφand Kc.In particular,with the increase in Kφand Kc,Fs increases by approximately 13%and 61.69%on average,respectively.Fs decreases rapidly with increasing slope gradientβand decreasing dimensionless parameterμ.When Kφand Kc are both less than 1.0,the stepped sliding surface occurs more easily than the plane failure surface,especially in the case of tensile failure of the rock bridge.In addition,rock slopes with higher strength parameters,taller heights,and greater weakening coefficients are prone to rock bridge tension failure with lower Fs,and more attention should be given to the occurrence of such accidents in actual engineering.展开更多
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
Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary pro...Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary process of red clay slopes and their connection to failure mechanisms is still poorly understood.A comprehensive approach integrating field investigation,laboratory tests,and numerical simulations was conducted to study the 168 red clay landslides in Xinshao County,China.The results show that red clay is prone to forming cracks at high moisture content due to its low swelling and high shrinkage properties.The failure mode of red clay slopes can be summarized in three stages:crack generation,slope excavation,and slope failure.Furthermore,the retrospective analysis and numerical simulations of the typical landslide in Guanchong indicated that intense rainfall primarily impacts the shallow layer of soil within approximately 0.5 m on the intact slope.However,cracks change the pattern of rainfall infiltration in the slope.Rainwater infiltrates rapidly through the preferential channels induced by the cracks rather than uniformly and slowly from the slope surface.This results in a significant increase in both the depth of infiltration and the saturated zone area of the cracked slope,reaching 3.8 m and 36.2 m^(2),respectively.Consequently,the factor of safety of the slope decreases by 13.4%compared to the intact slope,ultimately triggering landslides.This study can provide valuable insights into understanding the failure mechanisms of red clay slopes in China and other regions with similar geological settings.展开更多
Introduction: Omicron is a highly divergent variant of concern (VOCs) of a severe acute respiratory syndrome SARS-CoV-2. It carries a high number of mutations in its spike protein hence;it is more transmissible in the...Introduction: Omicron is a highly divergent variant of concern (VOCs) of a severe acute respiratory syndrome SARS-CoV-2. It carries a high number of mutations in its spike protein hence;it is more transmissible in the community by immune evasion mechanisms. Due to mutation within S gene, most Omicron variants have reported S gene target failure (SGTF) with some commercially available PCR kits. Such diagnostic features can be used as markers to screen Omicron. However, Whole Genome Sequencing (WGS) is the only gold standard approach to confirm novel microorganisms at genetically level as similar mutations can also be found in other variants that are circulating at low frequencies worldwide. This Retrospective study is aimed to assess RT-PCR sensitivity in the detection of S gene target failure in comparison with whole genome sequencing to detect variants of Omicron. Methods: We have analysed retrospective data of SARS-CoV-2 positive RT-PCR samples for S gene target failure (SGTF) with TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) and combined with sequencing technologies to study the emerged pattern of SARS-CoV-2 variants during third wave at the tertiary care centre, Surat. Results: From the first day of December 2021 till the end of February 2022, a total of 321,803 diagnostic RT-PCR tests for SARS-CoV-2 were performed, of which 20,566 positive cases were reported at our tertiary care centre with an average cumulative positivity of 6.39% over a period of three months. In the month of December 21 samples characterized by the SGTF (70/129) were suggestive of being infected by the Omicron variant and identified as Omicron (B.1.1.529 lineage) when sequence. In the month of January, we analysed a subset of samples (n = 618) with SGTF (24%) and without SGTF (76%) with Ct values Conclusions: During the COVID-19 pandemic, it took almost more than 15 days to diagnose infection and identify pathogen by sequencing technology. In contrast to that molecular assay provided quick identification with the help of SGTF phenomenon within 5 hours of duration. This strategy helps scientists and health policymakers for the quick isolation and identification of clusters. That ultimately results in a decreased transmission of pathogen among the community.展开更多
Background and Objectives: Chronic kidney disease (CKD) is now a global public health problem. In low- and middle-income countries such as the Congo, access to dialysis is low and inequitable. The prevention of CKD in...Background and Objectives: Chronic kidney disease (CKD) is now a global public health problem. In low- and middle-income countries such as the Congo, access to dialysis is low and inequitable. The prevention of CKD involves raising awareness among patients at risk, such as those suffering from arterial hypertension (AH), by improving their knowledge of CKD. The objectives of our work were to determine the level of knowledge about CKD among hypertensive patients and to identify the factors associated with a low level of knowledge. Methodology: We conducted a 3-month descriptive and analytical cross-sectional study from 1 August to 30 October 2023 in 3 large public hospitals in Brazzaville (capital of the Republic of Congo). We included: hypertensive patients aged 18 and over who had freely consented to participate in our study and were able to answer the questions on the survey form. Patients with known hypertension who had been followed for less than 3 years and those with known chronic renal failure were not included. Results: The mean age was 58.4 ± 14.4 years (29 - 88 years). There were 121 men and 150 women (sex ratio = 0.8). All the patients were educated;37.2% with a higher level of education and 13.6% with primary education. 24 patients (9%) had a good level of knowledge about CKD and 153 (56%) had poor knowledge. A good level of knowledge was associated with the duration of hypertension, intellectual level and the existence of associated heart disease. Conclusion: Our study reveals a significant lack of knowledge about chronic kidney disease among hypertensive patients in Brazzaville.展开更多
This paper presents a micromechanics-based Cosserat continuum model for microstructured granular materials.By utilizing this model,the macroscopic constitutive parameters of granular materials with different microstru...This paper presents a micromechanics-based Cosserat continuum model for microstructured granular materials.By utilizing this model,the macroscopic constitutive parameters of granular materials with different microstructures are expressed as sums of microstructural information.The microstructures under consideration can be classified into three categories:a medium-dense microstructure,a dense microstructure consisting of one-sized particles,and a dense microstructure consisting of two-sized particles.Subsequently,the Cosserat elastoplastic model,along with its finite element formulation,is derived using the extended Drucker-Prager yield criteria.To investigate failure behaviors,numerical simulations of granular materials with different microstructures are conducted using the ABAQUS User Element(UEL)interface.It demonstrates the capacity of the proposed model to simulate the phenomena of strain-softening and strain localization.The study investigates the influence of microscopic parameters,including contact stiffness parameters and characteristic length,on the failure behaviors of granularmaterials withmicrostructures.Additionally,the study examines themesh independence of the presented model and establishes its relationship with the characteristic length.A comparison is made between finite element simulations and discrete element simulations for a medium-dense microstructure,revealing a good agreement in results during the elastic stage.Somemacroscopic parameters describing plasticity are shown to be partially related to microscopic factors such as confining pressure and size of the representative volume element.展开更多
The latticed dunes in the Tengger Desert are widely distributed,and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities,posing a serious threat to the safe o...The latticed dunes in the Tengger Desert are widely distributed,and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities,posing a serious threat to the safe operation of the highway.To explore the local failure mechanism of sand-blocking fence in the latticed dune area,the local failure of sand-blocking fence in the latticed dune areas along the Wuhai-Maqin Highway in China was observed.Taking the first main ridge of the latticed dune as the placement location,the structure of the wind-sand flow field of sand-blocking fence placed at top,the bottom and the middle of windward slope was analyzed by Computational Fluid Dynamics(CFD).The results show that when placed at top of the first main ridge,the wind speed near the sand-blocking fence is the highest,up to 15.23 m/s.Therefore,the wind load strength on the sand barrier is correspondingly larger,up to 232.61 N∙m-2.As the strength of material continues to decrease,the nylon net is prone to breakage.The roots of the angle steel posts are susceptible to hollowing by vortex action,which can cause sand-blocking fence to fall over in strong wind conditions.When placed at the bottom of windward slope,wind speed drop near sand-blocking fence is greatest,with the decrease of 12.48-14.32 m/s compared to the original wind speed.This is highly likely to lead to large-scale deposition of sand particles and burial of the sand-blocking fence.When placed in the middle of windward slope,sand-blocking fence is subjected to less wind load strength(168.61N∙m-2)and sand particles are mostly deposited at the bottom of windward slope,with only a small amount of sand accumulating at the root of sand-blocking fence.Based on field observations and numerical modelling results,when the sand-blocking fence is placed in latticed dune area,it should be placed in the middle of the windward slope of the first main ridge as a matter of priority.Besides the sand-blocking fence should be placed at the top of the first main ridge,and sand fixing measures should be added.展开更多
BACKGROUND Cirrhotic patients with acute-on-chronic liver failure(ACLF)in the intensive care unit(ICU)have a poor but variable prognoses.Accurate prognosis evaluation can guide the rational management of patients with...BACKGROUND Cirrhotic patients with acute-on-chronic liver failure(ACLF)in the intensive care unit(ICU)have a poor but variable prognoses.Accurate prognosis evaluation can guide the rational management of patients with ACLF.However,existing prognostic scores for ACLF in the ICU environment lack sufficient accuracy.AIM To develop a new prognostic model for patients with ACLF in ICU.METHODS Data from 938 ACLF patients in the Medical Information Mart for Intensive Care(MIMIC)database were used to develop a new prognostic model(MIMIC ACLF)for ACLF.Discrimination,calibration and clinical utility of MIMIC ACLF were assessed by area under receiver operating characteristic curve(AUROC),calibration curve and decision curve analysis(DCA),respectively.MIMIC ACLF was then externally validated in a multiple-center cohort,the Electronic Intensive Care Collaborative Research Database and a single-center cohort from the Second Hospital of Hebei Medical University in China.RESULTS The MIMIC ACLF score was determined using nine variables:ln(age)×2.2+ln(white blood cell count)×0.22-ln(mean arterial pressure)×2.7+respiratory failure×0.6+renal failure×0.51+cerebral failure×0.31+ln(total bilirubin)×0.44+ln(internationalized normal ratio)×0.59+ln(serum potassium)×0.59.In MIMIC cohort,the AUROC(0.81/0.79)for MIMIC ACLF for 28/90-day ACLF mortality were significantly greater than those of Chronic Liver Failure Consortium ACLF(0.76/0.74),Model for End-stage Liver Disease(MELD;0.73/0.71)and MELD-Na(0.72/0.70)(all P<0.001).The consistency between actual and predicted 28/90-day survival rates of patients according to MIMIC ACLF score was excellent and superior to that of existing scores.The net benefit of MIMIC ACLF was greater than that achieved using existing scores within the 50%threshold probability.The superior predictive accuracy and clinical utility of MIMIC ACLF were validated in the external cohorts.CONCLUSION We developed and validated a new prognostic model with satisfactory accuracy for cirrhotic patients with ACLF hospitalized in the ICU.The model-based risk stratification and online calculator might facilitate the rational management of patients with ACLF.展开更多
基金supported by the grant from the National Natural Science Foundation of China (82070609)
文摘Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical illness.The pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ failure.Methods:Animals were divided into 3 groups,normal,thioacetamide(TAA,ALF model)and TAA+AGK2.Cultured L02 cells were divided into 5 groups,normal,TAA,TAA+mitofusin 2(MFN2)-siRNA,TAA+AGK2,and TAA+AGK2+MFN2-siRNA groups.The liver histology was evaluated with hematoxylin and eosin staining,inositol-requiring enzyme 1(IRE1),activating transcription factor 6β(ATF6β),protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)and phosphorylated-PERK(p-PERK).C/EBP homologous protein(CHOP),reactive oxygen species(ROS),MFN2 and glutathione peroxidase 4(GPX4)were measured with Western blotting,and cell viability and liver chemistry were also measured.Mitochondriaassociated endoplasmic reticulum membranes(MAMs)were measured by immunofluorescence.Results:The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis,which were reduced by AGK2 pre-treatment.In comparison to the normal group,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+in the TAA-induced ALF model group were significantly increased,which were decreased by AGK2 pre-treatment.The levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group,which were enhanced by AGK2 pretreatment.Compared with the TAA-induced L02 cell,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA group.AGK2 pre-treatment decreased the apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 cell.Immunofluorescence observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced group in both mice and L02 cells.Conclusions:The data suggested that AGK2 pre-treatment had hepatoprotective role in TAA-induced ALF via upregulating the expression of MFN2 and then inhibiting PERK and ferroptosis pathway in ALF.
基金The Financial Support Jointly by the National Research Council of Thailand and the German Research Foundation。
文摘The devastating 2004 tsunamis that hit the southwestern coast of Thailand pose a serious threat to people along the coastal zone. A major aim for the tsunami hazard prediction is better prediction of the next tsunamis and their impacts. In this paper, we present the first implications of recent slope failure events of the Andaman outer shelf and upper slope based on a new detailed bathymetric data and subbottom profiler records acquired during two cruises of the MASS project in 2006 and 2007. Morphometric analysis reveals a variety of anomalous features,including: three large plateaus surrounded by moats, ruggedness and unevenness of slope morphology, and two translational submarine landslides. Two submarine landslides are studied from the detailed bathymetric data and subbottom profiler record covering the upper slope of the Andaman Sea shelf break within Thai exclusive economic zone. Maximum approximated volumes of both displaced masses are 4.8×10~7 m~3 and 2.2×10~7 m~3.Considering the data, there is no evidence that landslides have been the sources for tsunami hazard potential in recent geological time. These prerequisites will allow better study of slope failure events in the area. Further investigation is required to better understand obvious geotectonic phenomena.
文摘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.
基金supported by the Natural Science Foundation of Hunan Province(2023JJ40078)the Scientific Research Project of Hunan Provincial Education Department(No.22C0573)+2 种基金the National Natural Science Foundation of China(51478477,51878668)Guizhou Provincial Department of Transportation Foundation(2017-122058)Foundation of Guizhou Provincial Science and Technology Department([2018]2815).
文摘Only simplified two-dimensional model and a single failure mode are adopted to calculate the ultimate pullout capacity(UPC)of anchor cables in most previous research.This study focuses on a more comprehensive combination failure mode that consists of bond failure of an anchorage body and failure of an anchored rock mass.The three-dimensional ultimate pullout capacity of the anchor cables is calculated based on the Hoek-Brown failure criterion and variation analysis method.The numerical solution for the curvilinear function in fracture plane is obtained based on the finite difference theory,which more accurately reflects the failure state of the anchor cable,as opposed to that being assumed in advance.The results reveal that relying solely on a single failure mode for UPC calculations has limitations,as changes in parameter values not only directly impact the UPC value but also can alter the failure model and thus the calculation method.
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(Nos.52208369,52309138,52209142,51978666)the Department of Science and Technology of Sichuan Province(2023NSFSC0284).
文摘In practical engineering,due to the noncontinuity characteristics of joints in rock slopes,in addition to plane failure,stepped sliding failure may occur for intermittently jointed rock slopes.Especially for intermittently bedding jointed rock slopes,the correlation and difference in strength parameters between joints and rock bridges,along with the various failure modes and intermittency of rock bridges,contribute to the complexity of stepped failure modes and the unpredictability of failure regions.Based on the upper-bound limit analysis method and multi-sliders step-path failure mode,considering the shear and tensile failure of rock bridges and the weakened relationship between the strength parameters of rock bridges and jointed surfaces,by introducing the modified M-C failure criterion and the formula for calculating the energy consumption of tensile failure of rock bridges,two failure mechanisms are constructed to obtain the safety factor(F_(s))of intermittently jointed rock slopes.The sequential quadratic programming method is used to obtain the optimal upper-bound solution for F_(s).The influence of multiple key parameters(slope height H,horizontal distance L,Slope angleβ,shear strength parameters of the rock bridgeφr and cr,Dimensionless parameter u,weakening coefficients of the internal friction angle and cohesion between the rock bridges and joint surfaces Kφand Kc)on the stability analysis of intermittently jointed rock slopes under the shear failure mode of rock bridges as well as under the tensile failure mode is also explored.The reliability of the failure mechanisms is verified by comparative analysis with theoretical results,numerical results,and landslide cases,and the variation rules of F_(s)with each key parameter are obtained.The results show that F_(s) varies linearly withφr and cr of the rock bridge and with K_(φ)and K_(c),whereas F_(s)changes nonlinearly with H and L.In particular,with the increase in Kφand Kc,Fs increases by approximately 52.78%and 171.02%on average,respectively.For rock bridge tensile failure,F_(s) shows a nonlinearly positive correlation withφr,cr,Kφand Kc.In particular,with the increase in Kφand Kc,Fs increases by approximately 13%and 61.69%on average,respectively.Fs decreases rapidly with increasing slope gradientβand decreasing dimensionless parameterμ.When Kφand Kc are both less than 1.0,the stepped sliding surface occurs more easily than the plane failure surface,especially in the case of tensile failure of the rock bridge.In addition,rock slopes with higher strength parameters,taller heights,and greater weakening coefficients are prone to rock bridge tension failure with lower Fs,and more attention should be given to the occurrence of such accidents in actual engineering.
文摘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.
基金supported by the National Natural Science Foundation of China(Project No.41920104007 and 41772334).
文摘Red clay landslides are widely distributed worldwide,resulting in severe loss of life and property.Although rainfall-induced red clay slopes have received extensive attention,the role of cracks in the evolutionary process of red clay slopes and their connection to failure mechanisms is still poorly understood.A comprehensive approach integrating field investigation,laboratory tests,and numerical simulations was conducted to study the 168 red clay landslides in Xinshao County,China.The results show that red clay is prone to forming cracks at high moisture content due to its low swelling and high shrinkage properties.The failure mode of red clay slopes can be summarized in three stages:crack generation,slope excavation,and slope failure.Furthermore,the retrospective analysis and numerical simulations of the typical landslide in Guanchong indicated that intense rainfall primarily impacts the shallow layer of soil within approximately 0.5 m on the intact slope.However,cracks change the pattern of rainfall infiltration in the slope.Rainwater infiltrates rapidly through the preferential channels induced by the cracks rather than uniformly and slowly from the slope surface.This results in a significant increase in both the depth of infiltration and the saturated zone area of the cracked slope,reaching 3.8 m and 36.2 m^(2),respectively.Consequently,the factor of safety of the slope decreases by 13.4%compared to the intact slope,ultimately triggering landslides.This study can provide valuable insights into understanding the failure mechanisms of red clay slopes in China and other regions with similar geological settings.
文摘Introduction: Omicron is a highly divergent variant of concern (VOCs) of a severe acute respiratory syndrome SARS-CoV-2. It carries a high number of mutations in its spike protein hence;it is more transmissible in the community by immune evasion mechanisms. Due to mutation within S gene, most Omicron variants have reported S gene target failure (SGTF) with some commercially available PCR kits. Such diagnostic features can be used as markers to screen Omicron. However, Whole Genome Sequencing (WGS) is the only gold standard approach to confirm novel microorganisms at genetically level as similar mutations can also be found in other variants that are circulating at low frequencies worldwide. This Retrospective study is aimed to assess RT-PCR sensitivity in the detection of S gene target failure in comparison with whole genome sequencing to detect variants of Omicron. Methods: We have analysed retrospective data of SARS-CoV-2 positive RT-PCR samples for S gene target failure (SGTF) with TaqPath COVID-19 RT-PCR Combo Kit (ThermoFisher) and combined with sequencing technologies to study the emerged pattern of SARS-CoV-2 variants during third wave at the tertiary care centre, Surat. Results: From the first day of December 2021 till the end of February 2022, a total of 321,803 diagnostic RT-PCR tests for SARS-CoV-2 were performed, of which 20,566 positive cases were reported at our tertiary care centre with an average cumulative positivity of 6.39% over a period of three months. In the month of December 21 samples characterized by the SGTF (70/129) were suggestive of being infected by the Omicron variant and identified as Omicron (B.1.1.529 lineage) when sequence. In the month of January, we analysed a subset of samples (n = 618) with SGTF (24%) and without SGTF (76%) with Ct values Conclusions: During the COVID-19 pandemic, it took almost more than 15 days to diagnose infection and identify pathogen by sequencing technology. In contrast to that molecular assay provided quick identification with the help of SGTF phenomenon within 5 hours of duration. This strategy helps scientists and health policymakers for the quick isolation and identification of clusters. That ultimately results in a decreased transmission of pathogen among the community.
文摘Background and Objectives: Chronic kidney disease (CKD) is now a global public health problem. In low- and middle-income countries such as the Congo, access to dialysis is low and inequitable. The prevention of CKD involves raising awareness among patients at risk, such as those suffering from arterial hypertension (AH), by improving their knowledge of CKD. The objectives of our work were to determine the level of knowledge about CKD among hypertensive patients and to identify the factors associated with a low level of knowledge. Methodology: We conducted a 3-month descriptive and analytical cross-sectional study from 1 August to 30 October 2023 in 3 large public hospitals in Brazzaville (capital of the Republic of Congo). We included: hypertensive patients aged 18 and over who had freely consented to participate in our study and were able to answer the questions on the survey form. Patients with known hypertension who had been followed for less than 3 years and those with known chronic renal failure were not included. Results: The mean age was 58.4 ± 14.4 years (29 - 88 years). There were 121 men and 150 women (sex ratio = 0.8). All the patients were educated;37.2% with a higher level of education and 13.6% with primary education. 24 patients (9%) had a good level of knowledge about CKD and 153 (56%) had poor knowledge. A good level of knowledge was associated with the duration of hypertension, intellectual level and the existence of associated heart disease. Conclusion: Our study reveals a significant lack of knowledge about chronic kidney disease among hypertensive patients in Brazzaville.
基金the National Natural Science Foundation of China through Contract/Grant Numbers 12002245,12172263 and 11772237Chongqing Jiaotong University through Contract/Grant Number F1220038.
文摘This paper presents a micromechanics-based Cosserat continuum model for microstructured granular materials.By utilizing this model,the macroscopic constitutive parameters of granular materials with different microstructures are expressed as sums of microstructural information.The microstructures under consideration can be classified into three categories:a medium-dense microstructure,a dense microstructure consisting of one-sized particles,and a dense microstructure consisting of two-sized particles.Subsequently,the Cosserat elastoplastic model,along with its finite element formulation,is derived using the extended Drucker-Prager yield criteria.To investigate failure behaviors,numerical simulations of granular materials with different microstructures are conducted using the ABAQUS User Element(UEL)interface.It demonstrates the capacity of the proposed model to simulate the phenomena of strain-softening and strain localization.The study investigates the influence of microscopic parameters,including contact stiffness parameters and characteristic length,on the failure behaviors of granularmaterials withmicrostructures.Additionally,the study examines themesh independence of the presented model and establishes its relationship with the characteristic length.A comparison is made between finite element simulations and discrete element simulations for a medium-dense microstructure,revealing a good agreement in results during the elastic stage.Somemacroscopic parameters describing plasticity are shown to be partially related to microscopic factors such as confining pressure and size of the representative volume element.
文摘The latticed dunes in the Tengger Desert are widely distributed,and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities,posing a serious threat to the safe operation of the highway.To explore the local failure mechanism of sand-blocking fence in the latticed dune area,the local failure of sand-blocking fence in the latticed dune areas along the Wuhai-Maqin Highway in China was observed.Taking the first main ridge of the latticed dune as the placement location,the structure of the wind-sand flow field of sand-blocking fence placed at top,the bottom and the middle of windward slope was analyzed by Computational Fluid Dynamics(CFD).The results show that when placed at top of the first main ridge,the wind speed near the sand-blocking fence is the highest,up to 15.23 m/s.Therefore,the wind load strength on the sand barrier is correspondingly larger,up to 232.61 N∙m-2.As the strength of material continues to decrease,the nylon net is prone to breakage.The roots of the angle steel posts are susceptible to hollowing by vortex action,which can cause sand-blocking fence to fall over in strong wind conditions.When placed at the bottom of windward slope,wind speed drop near sand-blocking fence is greatest,with the decrease of 12.48-14.32 m/s compared to the original wind speed.This is highly likely to lead to large-scale deposition of sand particles and burial of the sand-blocking fence.When placed in the middle of windward slope,sand-blocking fence is subjected to less wind load strength(168.61N∙m-2)and sand particles are mostly deposited at the bottom of windward slope,with only a small amount of sand accumulating at the root of sand-blocking fence.Based on field observations and numerical modelling results,when the sand-blocking fence is placed in latticed dune area,it should be placed in the middle of the windward slope of the first main ridge as a matter of priority.Besides the sand-blocking fence should be placed at the top of the first main ridge,and sand fixing measures should be added.
文摘BACKGROUND Cirrhotic patients with acute-on-chronic liver failure(ACLF)in the intensive care unit(ICU)have a poor but variable prognoses.Accurate prognosis evaluation can guide the rational management of patients with ACLF.However,existing prognostic scores for ACLF in the ICU environment lack sufficient accuracy.AIM To develop a new prognostic model for patients with ACLF in ICU.METHODS Data from 938 ACLF patients in the Medical Information Mart for Intensive Care(MIMIC)database were used to develop a new prognostic model(MIMIC ACLF)for ACLF.Discrimination,calibration and clinical utility of MIMIC ACLF were assessed by area under receiver operating characteristic curve(AUROC),calibration curve and decision curve analysis(DCA),respectively.MIMIC ACLF was then externally validated in a multiple-center cohort,the Electronic Intensive Care Collaborative Research Database and a single-center cohort from the Second Hospital of Hebei Medical University in China.RESULTS The MIMIC ACLF score was determined using nine variables:ln(age)×2.2+ln(white blood cell count)×0.22-ln(mean arterial pressure)×2.7+respiratory failure×0.6+renal failure×0.51+cerebral failure×0.31+ln(total bilirubin)×0.44+ln(internationalized normal ratio)×0.59+ln(serum potassium)×0.59.In MIMIC cohort,the AUROC(0.81/0.79)for MIMIC ACLF for 28/90-day ACLF mortality were significantly greater than those of Chronic Liver Failure Consortium ACLF(0.76/0.74),Model for End-stage Liver Disease(MELD;0.73/0.71)and MELD-Na(0.72/0.70)(all P<0.001).The consistency between actual and predicted 28/90-day survival rates of patients according to MIMIC ACLF score was excellent and superior to that of existing scores.The net benefit of MIMIC ACLF was greater than that achieved using existing scores within the 50%threshold probability.The superior predictive accuracy and clinical utility of MIMIC ACLF were validated in the external cohorts.CONCLUSION We developed and validated a new prognostic model with satisfactory accuracy for cirrhotic patients with ACLF hospitalized in the ICU.The model-based risk stratification and online calculator might facilitate the rational management of patients with ACLF.
