Temporary mechanical circulatory support (tMCS) devices such as intra-aorticballoon pumps, veno-arterial extracorporeal membrane oxygenation, and percutaneousventricular assist devices, play a major role in supporting...Temporary mechanical circulatory support (tMCS) devices such as intra-aorticballoon pumps, veno-arterial extracorporeal membrane oxygenation, and percutaneousventricular assist devices, play a major role in supporting patients withend-stage heart failure and bridging them to transplant. In 2018, the United Networkfor Organ Sharing heart allocation criteria was modified by increasing thenumber of statuses in the heart transplant waitlist to differentiate and favor thesickest patients awaiting transplantation. Within this new system, patients withtMCS devices receive the highest priority statuses. While the 2018 allocationsystem has reduced waitlist times and mortality for the highest-priority patients,some studies have shown a concomitant rise in the utilization of tMCS devices asbridge to transplant after its enaction. In this narrative review, we describe thesechanges in tMCS utilization and provide insights on how the upcoming creationof a continuous distribution allocation system may further impact these trends.展开更多
Objective To investigate the clinical outcomes of children with congenital heart disease （CHD） requiring extracorporeal membrane oxygenation （ECMO） and left ventricular assist device （LVAD） support after cardiac...Objective To investigate the clinical outcomes of children with congenital heart disease （CHD） requiring extracorporeal membrane oxygenation （ECMO） and left ventricular assist device （LVAD） support after cardiac surgery. Methods A total of 22 patients with CHD who required postcardiotomy mechanical circulatory support between March 2004 and March 2011 （85 months ） were analyzed retrospectively. Median age of the patients was 420 d （ 15 d - 4 years） and median weight was 3.4 kg （ 2 - 14. 5 kg ）. Eight patients were put on ECMO, while 14 patients were placed on LVAD. Results Thirteen （59%） patients died and 9 （41% ） survived to discharge. In survivals, the duration of LVAD and the duration of ECMO were both shorter than those of nonsurvivals （P 〈 O. 05）. The main complication was bleeding. Conclusion The earlier treatment and application of more advanced cardiac support devices for CHD patients are key factors for reducing complications.展开更多
BACKGROUND Acute and extreme insulin resistance with persistent hyperglycemia requiring excessively high doses of insulin before rapidly resolving is rare and has been referred to as transient and extreme insulin resi...BACKGROUND Acute and extreme insulin resistance with persistent hyperglycemia requiring excessively high doses of insulin before rapidly resolving is rare and has been referred to as transient and extreme insulin resistance(TEIR).The underlying pathophysiology and optimal management of TEIR are poorly understood,and previous reports of TEIR in the literature are sparse.This report is the first description of TEIR in a patient requiring mechanical circulatory support(MCS).CASE SUMMARY A 62-year-old male developed cardiogenic shock and was placed on veno-arterial extracorporeal membrane oxygenation following percutaneous coronary intervention and successful revascularization.Over the next 24 hours,glucose levels rose and remained markedly elevated despite increasing insulin infusion rates and repeated boluses.The insulin infusion rate peaked at 450 units/hour,and the patient received 4300 units(33 units/kg)of insulin over the 24-hour period of peak insulin resistance.Insulin resistance resolved rapidly,necessitating an abrupt decrease in the insulin infusion rate and development of rebound hypoglycemia.CONCLUSION Onset of TEIR did not seem to correlate with end-organ hypoperfusion or vasoactive drug dosing.展开更多
Heart transplantation(HTx)is a life-saving procedure for patients with end-stage heart failure and has undergone remarkable advancements since the first succe-ssful transplant in 1967.The introduction of cyclosporine ...Heart transplantation(HTx)is a life-saving procedure for patients with end-stage heart failure and has undergone remarkable advancements since the first succe-ssful transplant in 1967.The introduction of cyclosporine in the 1970s significantly improved patient outcomes,leading to a global increase in transplants,including in India,where the practice has grown despite initial challenges.This review pro-vides an extensive overview of HTx,focusing on current practices,technological advancements,and the ongoing challenges the field faces today.It explores the evolution of surgical techniques,such as minimally invasive and robotic-assisted procedures,and the management of posttransplant rejection through tailored immunosuppressive strategies,including new monoclonal antibodies and perso-nalized therapies.The review also highlights emerging innovations such as mechanical circulatory support devices and xenotransplantation as potential solutions to donor shortages while acknowledging the ethical and logistical challenges these approaches entail.Furthermore,the analysis delves into the implications of using extended-criteria donors and the role of multidisciplinary teams in evaluating absolute and relative contraindications.Despite the progress made,the persistent issues of organ scarcity and ethical concerns underscore the need for ongoing research and innovation to further enhance the efficacy,safety,and accessibility of HTx.展开更多
While biventricular assist devices(BiVADs)remain underutilized in Western countries for biventricular heart failure(BHF),their application is expanding in China.This consensus synthesizes international guidelines,medi...While biventricular assist devices(BiVADs)remain underutilized in Western countries for biventricular heart failure(BHF),their application is expanding in China.This consensus synthesizes international guidelines,medical evidence,and Chinese clinical expertise to establish standardized protocols for BiVAD management.Key recommendations include:(1)Preoperative right heart catheterization and echocardiography for central venous pressure(CVP):pulmonary capillary wedge pressure(PCWP)ratio and pulmonary artery pulsatility index(PAPi)assessment(Class I);(2)BiVAD indication in refractory BHF or high-risk right heart failure post-left ventricular assist device(LVAD)implantation(Class IIa);(3)Right atrial implantation as the preferred surgical approach(Class IIa);(4)Warfarin-based anticoagulation(INR 2.0–2.5)with aspirin,avoiding direct oral anticoagulants(DOACs)(Class III).The guidance addresses critical gaps in patient selection,pump speed titration,and complication management,positioning integrated BiVAD systems as a promising solution for complex BHF.展开更多
This review comprehensively examines acute myocardial infarction with ventricular septal rupture(VSR),a rare yet lethal complication.We analyze its epidemiological,pathophysiological,clinical,and therapeutic aspects,e...This review comprehensively examines acute myocardial infarction with ventricular septal rupture(VSR),a rare yet lethal complication.We analyze its epidemiological,pathophysiological,clinical,and therapeutic aspects,emphasizing innovative strategies like bioabsorbable occluders and tissue engineering to reduce complications and improve prognosis.The integration of artificial intelligence and big data analytics for treatment decision-making and personalized surgical timing models is highlighted as transformative.Our analysis underscores the need for early diagnosis and tailored interventions,proposing future research directions in molecular mechanisms,multidisciplinary collaboration,and technology integration.These innovations promise to enhance VSR management and extend to other cardiovascular diseases,heralding a new era of precision and regenerative cardiovascular medicine.展开更多
By applying experimental method, the bolt stress and supporting mechanism is studied during the deformation process of a rock mass containing a weak interlayer. The force measuring bolt is installed manually and instr...By applying experimental method, the bolt stress and supporting mechanism is studied during the deformation process of a rock mass containing a weak interlayer. The force measuring bolt is installed manually and instrumented five pairs of symmetrical strain gauges. The experimental results show that the fully grouted bolt suffers tensile, compressive, bending and shear stress at the same time. The bolt stress evolution is closely related to the deformation stages of the rock mass which are very gradually varying stage, gradually varying stage at the pre-peak and suddenly varying stage at the post peak stage.The axial compressive stress in the bolt is mainly induced by the moment. Thus, in most cases the axial compressive stress is distributed on one side of the bolt. For axial stresses, induced by the axial force and the bending moment at the post-peak stage, three types of changing are observed, viz. increasingincreasing type, decreasing-increasing type and increasing-decreasing type. The stress characteristics of the bolt section in the weak interlayer are significantly different from those in the hard rock. The failure models of the anchored bolt are tensile failure and shear failure, respectively. The bolt not only provides constraints on the free surface of the rock mass, but also resists the axial and lateral loading by the bending moment. This study provides valuable guidelines for bolting support design and its safety assessment.展开更多
For a soft rock tunnel under high stress in jointed and swell soft rock （HJS）, two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC20, and the deformati...For a soft rock tunnel under high stress in jointed and swell soft rock （HJS）, two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC20, and the deformation effects of the two construction schemes were verified by field tests. Based on engineer- ing geological investigation and mechanical analysis of large deformations, the complex deformation mechanisms of stress expansion and structural deformation of the soft rock tunnel were confirmed, and support countermeasures from the complex deformation mechanism converted to a single type were proposed, and the support parameters were optimized by field tests. These technologies were proved by engineering practice, which produced significant technical and economic benefits.展开更多
Geomechanics in deep mines becomes more complex and structural support in soft rock can be very difficult.Highly stressed soft rock subject to expansion deformation is particularly difficult to control.The Tiefa Coal ...Geomechanics in deep mines becomes more complex and structural support in soft rock can be very difficult.Highly stressed soft rock subject to expansion deformation is particularly difficult to control.The Tiefa Coal Industry Group Daqiang Coal Mine is used as an example.A ventilation shaft,à550 horsehead,is located in tertiary soft rock.Analysis of the reasons for deformation shows an intumescent rock,which is easily damaged.Field observations and theoretical analysis led to a design capable of stabilizing the rock.A combination of spray,anchors,anchor bolts,and soft corner coupled truss supports allowed the deformation to be controlled.This provides a model for similar designs when support of a horsehead roadway is required.展开更多
Large pressure equipment needs to be tested regularly to ensure safe operation;wall-climbing robots can carry the necessary tools to inspect spherical tanks,such as cameras and non-destructive testing equipment.Howeve...Large pressure equipment needs to be tested regularly to ensure safe operation;wall-climbing robots can carry the necessary tools to inspect spherical tanks,such as cameras and non-destructive testing equipment.However,a wall-climbing robot inside a spherical tank cannot be accurately positioned owing to the particularity of the spherical tank structure.This paper proposes a passive support and positioning mechanism fixed in a spherical tank to improve the adsorption capacity and positioning accuracy of the inspection robot.The main body of the mechanism was designed as a truss composed of carbon fiber telescopic rods and can work in spherical tanks with diameters of 4.6-15.7 m.The structural strength,stiffness,and stability of the mechanism are analyzed via force and deformation simulations.By constructing a mathematical model of the support and positioning mechanism,the influence of structural deformation on the supporting capacity is analyzed and calculated.The robot positioning method based on the support and positioning mechanism can effectively locate the robot inside a spherical tank.Experiments verified the support performance and robot positioning accuracy of the mechanism.This research proposes an auxiliary support and positioning mechanism for a detection robot inside a spherical tank,which can effectively improve the positioning accuracy of the robot and meet the robotic inspection requirements.展开更多
In order to enhance the sealing quality and assemble efficiency of hydraulic supports, the evaluation system for the sealability of the hydraulic support and jack＇s seals was established through the testing and exper...In order to enhance the sealing quality and assemble efficiency of hydraulic supports, the evaluation system for the sealability of the hydraulic support and jack＇s seals was established through the testing and experimenting technology in respects, such as seals＇ dimensions, reasonable amounts of compression, sealability, life, resistance to pressure, etc. Through life detecting test of the seal, found the longest life seal ring under the same conditions, and through the reciprocating test of the hydraulic support, found the most appropriate amount of interference between the groove and the seal ring, thus, to decrease the leakage and extend the life span of the hydraulic support.展开更多
In order to avoid the deep-well oil shale roadway being deformed, damaged, or difficult to maintain after excavating and supporting in Haishiwan coal mine, this paper has analyzed the characteristics of the deformed r...In order to avoid the deep-well oil shale roadway being deformed, damaged, or difficult to maintain after excavating and supporting in Haishiwan coal mine, this paper has analyzed the characteristics of the deformed roadway and revealed its failure mechanism by taking comprehensively the methods of field geological investigation, displacement monitoring of surrounding rock, rock properties and hydration properties experiments and field application tests. Based on this work, the high-resistance controlled yielding supporting principle is proposed, which is： to ＂resist＂ by high pre-tightening force and high stiff- ness in the early stage, to ＂yield＂ by making use of the controlled deformation of a yielding tube in the middle stage, and to ＂fix＂ by applying total-section Gunite in the later stage. A high-resistance controlled yielding supporting technique of ＂high pre-tightening force yielding anchor bolt ＋ small-bore pre-tight- ening force anchor cable ＋ rebar ladder beam ＋ rhombic metal mesh ＋ lagging gunite＂ has been estab- lished, and industrial on site testing implemented. The practical results show that the high-resistance controlled yielding supporting technique can effectively control the large deformation and long-time rheology of deep-well oil shale roadways and can provide beneficial references for the maintenance of other con-generic roadways.Deep-well Oil shale展开更多
This paper takes No.52 return uphill roadway of Yangquhe coal mine as a research project. Based on the research, especially its geological condition, indoor experiments, numerical simulation and theoretical analysis w...This paper takes No.52 return uphill roadway of Yangquhe coal mine as a research project. Based on the research, especially its geological condition, indoor experiments, numerical simulation and theoretical analysis were employed to determine the difficult coefficients of Yangquhe project. By using these means,the difficult coefficients of the deep rock engineering were determined. From a study of the effects of crustal stress and the roof mechanism on roadway stability, the transformation mechanism in Yangquhe coal mine has been determined. As a result of this research, the interactive support technology of prestressed cable mesh was developed and the technology tested in mining engineering, which proved to be feasible.展开更多
BACKGROUND Coronavirus disease 2019(COVID-19)severity is classified as asymptomatic,mild,moderate,severe,and critical.Mild cases account for a large percentage of cases in the epidemic and typically exhibit a favorabl...BACKGROUND Coronavirus disease 2019(COVID-19)severity is classified as asymptomatic,mild,moderate,severe,and critical.Mild cases account for a large percentage of cases in the epidemic and typically exhibit a favorable prognosis.However,a 49%-67%mortality is noted in critical cases.No COVID-19-specific drug has been reported to date,and symptomatic and optimal supportive care,including oxygenation,anti-coinfection treatments,and ventilation,represent the mainstay of treatment for this disease,especially in critical patients.CASE SUMMARY In the above-mentioned context,we share our experience with the treatment of one critical COVID-19 case and review the relevant literature.CONCLUSION Timely tracheal intubation,reasonable mechanical ventilation support,appropriate anti-infection treatment,and early anticoagulation and immunity support are key factors in the successful treatment of this case.展开更多
According to the research results in world, the paper comprehensively analyzed and gave a demonstration of mechanism of single-truss and its stressing advantage. Comparison and analysis effect were given to single-tru...According to the research results in world, the paper comprehensively analyzed and gave a demonstration of mechanism of single-truss and its stressing advantage. Comparison and analysis effect were given to single-truss and bolting supporting. By the way of element simulation. The paper shows that single truss supporting have better effect to bolting supporting to improving the stress condition of surrounding rocks, controlling the surrounding rocks plastic failure development zone and deformation effect of surrounding rocks, which provided the elementary theory basis to the research, experiment and expanding the single-truss bolting technology in colliery.展开更多
The truss cable support technology was put forward to control the large mining height and composite mudstone strata roadway. This technique makes the steady rock in roadway slantwise top be anchor points, makes the tr...The truss cable support technology was put forward to control the large mining height and composite mudstone strata roadway. This technique makes the steady rock in roadway slantwise top be anchor points, makes the truss cable be steady support structure through special implement, and supplied rock in anchor area with horizontal and vertical pressure which strengthens the surrounding rock＇s anti-strain capability, so it can solve the support problem in roadway with the large cross section and large mining height with mudstone strata. The support mechanism of truss cable about how to make the soft strata stabilize is analyzed by use of the mechanical method. Based on the mechanism and numerical simulation method, the truss cable support project was designed and used to the large mining setting room in eleventh mining area of Bailong Mine successfully.展开更多
Support vector regression （SVR） combined with particle swarm optimization for its parameter optimization is employed to establish a model for predicting the Henry constants of multi-walled carbon nanotubes （MWNTs）...Support vector regression （SVR） combined with particle swarm optimization for its parameter optimization is employed to establish a model for predicting the Henry constants of multi-walled carbon nanotubes （MWNTs） for adsorption of volatile organic compounds （VOCs）. The prediction performance of SVR is compared with those of the model of theoretical linear salvation energy relationship （TLSER）. By using leave-one-out cross validation of SVR test Henry constants for adsorption of 35 VOCs on MWNTs, the root mean square error is 0.080, the mean absolute percentage error is only 1.19~, and the correlation coefficient （R2） is as high as 0.997. Compared with the results of the TLSER model, it is shown that the estimated errors by SVR are ali smaller than those achieved by TLSER. It reveals that the generalization ability of SVR is superior to that of the TLSER model Meanwhile, multifactor analysis is adopted for investigation of the influences of each molecular structure descriptor on the Henry constants. According to the TLSER model, the adsorption mechanism of adsorption of carbon nanotubes of VOCs is mainly a result of van der Waals and interactions of hydrogen bonds. These can provide the theoretical support for the application of carbon nanotube adsorption of VOCs and can make up for the lack of experimental data.展开更多
In recent years, human society has achieved rapid development and progress, in this process, a large amount of energy is developed and utilized, which eventually leads to the problem of energy shortage. In order to ef...In recent years, human society has achieved rapid development and progress, in this process, a large amount of energy is developed and utilized, which eventually leads to the problem of energy shortage. In order to effectively alleviate the current energy shortage problem, people have invested a lot of manpower and material resources in the research and development of new energy, which has laid a solid foundation for the sustainable and stable development of human society. In terms of today's actual situation, global oil and coal energy accounts for a large proportion in the total energy, but after being exploited and utilized in large quantities, it shows a trend of decline year by year. Renewable and environmental protection characteristics of new energy make it the most potential energy at present. We believe that new energy will inevitably trigger an industrial revolution in the future. In order to effectively promote the sustainable and stable development of the new energy industry, the most important thing is to obtain the support of the continuous market. Simply relying on government subsidies is unable to meet the actual needs of the industry development, so we need to look for more additional capital market support. Although the development of China's new energy industry has reached a high level in the whole world, photovoltaic power generation accounts for 30 percent of the world's total, the industrial development speed has exceeded the United States and Germany, the market has a good prospect in the future. However, long-term dependence on government subsidies leads to the lack of driving force for industrial development. Therefore, we urgently need the necessary support from the capital market to alleviate the above problems. In view of this, this paper mainly focuses on the capital market supporting mechanism for the development of new energy industry to carry out practical analysis and research, hoping to be helpful to the healthy and stable development of China's new energy field.展开更多
The close coal seam group exists in Datong, Xishan, Huozhou, Fenxi and other coalfields. At the same time, the strata between coal seams are usually soft rock composite strata and soft rock composite strata. Because t...The close coal seam group exists in Datong, Xishan, Huozhou, Fenxi and other coalfields. At the same time, the strata between coal seams are usually soft rock composite strata and soft rock composite strata. Because the coal seam is affected by the mine pressure, the integrity of the original surrounding rock cannot be guaranteed, and the joint and crack of the composite weak roof of the lower coal seam are damaged, so it is difficult to control the roadway roof during the excavation, which leads to the phenomenon of spalling or roof fall, and brings difficulties to the periodic maintenance and support work. Based on the analysis of the transportation roadway in coal mining face, the roadway layout and roof support under the condition of short distance coal seam goaf and compound soft roof are studied, so as to provide help for the safe construction of coal mining face under such conditions.展开更多
Electrical storm(ES) is a medical emergency characterized by repetitive episodes of sustained ventriculararrhythmias(VAs) in a limited amount of time(at least 3 within a 24-h period) leading to repeated appropriate im...Electrical storm(ES) is a medical emergency characterized by repetitive episodes of sustained ventriculararrhythmias(VAs) in a limited amount of time(at least 3 within a 24-h period) leading to repeated appropriate implantable cardioverter defibrillator therapies. The occurrence of ES represents a major turning point in the natural history of patients with structural heart disease being associated with poor short-and longterm survival particularly in those with compromised left ventricular ejection fraction(LVEF) that can develop hemodynamic decompensation and multi-organ failure. Management of ES is challenging with limited available evidence coming from small retrospective series and a substantial lack of randomized-controlled trials. In general, a multidisciplinary approach including medical therapies such as anti-arrhythmic drugs, sedation, as well as interventional approaches like catheter ablation, may be required. Accurate patient risk stratification at admission for ES is pivotal and should take into account hemodynamic tolerability of VAs as well as comorbidities like low LVEF, advanced NYHA class and chronic pulmonary disease. In high risk patients, prophylactic mechanical circulatory support with left ventricular assistance devices or extracorporeal membrane oxygenation should be considered as bridge to ablation and recovery. In the present manuscript we review the available strategies for management of ES and the evidence supporting them.展开更多
文摘Temporary mechanical circulatory support (tMCS) devices such as intra-aorticballoon pumps, veno-arterial extracorporeal membrane oxygenation, and percutaneousventricular assist devices, play a major role in supporting patients withend-stage heart failure and bridging them to transplant. In 2018, the United Networkfor Organ Sharing heart allocation criteria was modified by increasing thenumber of statuses in the heart transplant waitlist to differentiate and favor thesickest patients awaiting transplantation. Within this new system, patients withtMCS devices receive the highest priority statuses. While the 2018 allocationsystem has reduced waitlist times and mortality for the highest-priority patients,some studies have shown a concomitant rise in the utilization of tMCS devices asbridge to transplant after its enaction. In this narrative review, we describe thesechanges in tMCS utilization and provide insights on how the upcoming creationof a continuous distribution allocation system may further impact these trends.
文摘Objective To investigate the clinical outcomes of children with congenital heart disease （CHD） requiring extracorporeal membrane oxygenation （ECMO） and left ventricular assist device （LVAD） support after cardiac surgery. Methods A total of 22 patients with CHD who required postcardiotomy mechanical circulatory support between March 2004 and March 2011 （85 months ） were analyzed retrospectively. Median age of the patients was 420 d （ 15 d - 4 years） and median weight was 3.4 kg （ 2 - 14. 5 kg ）. Eight patients were put on ECMO, while 14 patients were placed on LVAD. Results Thirteen （59%） patients died and 9 （41% ） survived to discharge. In survivals, the duration of LVAD and the duration of ECMO were both shorter than those of nonsurvivals （P 〈 O. 05）. The main complication was bleeding. Conclusion The earlier treatment and application of more advanced cardiac support devices for CHD patients are key factors for reducing complications.
文摘BACKGROUND Acute and extreme insulin resistance with persistent hyperglycemia requiring excessively high doses of insulin before rapidly resolving is rare and has been referred to as transient and extreme insulin resistance(TEIR).The underlying pathophysiology and optimal management of TEIR are poorly understood,and previous reports of TEIR in the literature are sparse.This report is the first description of TEIR in a patient requiring mechanical circulatory support(MCS).CASE SUMMARY A 62-year-old male developed cardiogenic shock and was placed on veno-arterial extracorporeal membrane oxygenation following percutaneous coronary intervention and successful revascularization.Over the next 24 hours,glucose levels rose and remained markedly elevated despite increasing insulin infusion rates and repeated boluses.The insulin infusion rate peaked at 450 units/hour,and the patient received 4300 units(33 units/kg)of insulin over the 24-hour period of peak insulin resistance.Insulin resistance resolved rapidly,necessitating an abrupt decrease in the insulin infusion rate and development of rebound hypoglycemia.CONCLUSION Onset of TEIR did not seem to correlate with end-organ hypoperfusion or vasoactive drug dosing.
文摘Heart transplantation(HTx)is a life-saving procedure for patients with end-stage heart failure and has undergone remarkable advancements since the first succe-ssful transplant in 1967.The introduction of cyclosporine in the 1970s significantly improved patient outcomes,leading to a global increase in transplants,including in India,where the practice has grown despite initial challenges.This review pro-vides an extensive overview of HTx,focusing on current practices,technological advancements,and the ongoing challenges the field faces today.It explores the evolution of surgical techniques,such as minimally invasive and robotic-assisted procedures,and the management of posttransplant rejection through tailored immunosuppressive strategies,including new monoclonal antibodies and perso-nalized therapies.The review also highlights emerging innovations such as mechanical circulatory support devices and xenotransplantation as potential solutions to donor shortages while acknowledging the ethical and logistical challenges these approaches entail.Furthermore,the analysis delves into the implications of using extended-criteria donors and the role of multidisciplinary teams in evaluating absolute and relative contraindications.Despite the progress made,the persistent issues of organ scarcity and ethical concerns underscore the need for ongoing research and innovation to further enhance the efficacy,safety,and accessibility of HTx.
文摘While biventricular assist devices(BiVADs)remain underutilized in Western countries for biventricular heart failure(BHF),their application is expanding in China.This consensus synthesizes international guidelines,medical evidence,and Chinese clinical expertise to establish standardized protocols for BiVAD management.Key recommendations include:(1)Preoperative right heart catheterization and echocardiography for central venous pressure(CVP):pulmonary capillary wedge pressure(PCWP)ratio and pulmonary artery pulsatility index(PAPi)assessment(Class I);(2)BiVAD indication in refractory BHF or high-risk right heart failure post-left ventricular assist device(LVAD)implantation(Class IIa);(3)Right atrial implantation as the preferred surgical approach(Class IIa);(4)Warfarin-based anticoagulation(INR 2.0–2.5)with aspirin,avoiding direct oral anticoagulants(DOACs)(Class III).The guidance addresses critical gaps in patient selection,pump speed titration,and complication management,positioning integrated BiVAD systems as a promising solution for complex BHF.
基金Supported by Science and Technology Department of Yunnan Province-Kunming Medical University,Kunming Medical Joint Special Project-Surface Project,China,No.202401AY070001-164Yunnan Provincial Department of Science and Technology Science and Technology Plan Project—Major Science and Technology Special Projects,No.202405AJ310003.
文摘This review comprehensively examines acute myocardial infarction with ventricular septal rupture(VSR),a rare yet lethal complication.We analyze its epidemiological,pathophysiological,clinical,and therapeutic aspects,emphasizing innovative strategies like bioabsorbable occluders and tissue engineering to reduce complications and improve prognosis.The integration of artificial intelligence and big data analytics for treatment decision-making and personalized surgical timing models is highlighted as transformative.Our analysis underscores the need for early diagnosis and tailored interventions,proposing future research directions in molecular mechanisms,multidisciplinary collaboration,and technology integration.These innovations promise to enhance VSR management and extend to other cardiovascular diseases,heralding a new era of precision and regenerative cardiovascular medicine.
基金support of the National Basic Research 973 Program of China (No.2013CB036003)the National Natural Science Foundation of China (No.51374198)the National Natural Science Foundation young investigator grant program of China (Nos.51204163,51504247,and 51404255)
文摘By applying experimental method, the bolt stress and supporting mechanism is studied during the deformation process of a rock mass containing a weak interlayer. The force measuring bolt is installed manually and instrumented five pairs of symmetrical strain gauges. The experimental results show that the fully grouted bolt suffers tensile, compressive, bending and shear stress at the same time. The bolt stress evolution is closely related to the deformation stages of the rock mass which are very gradually varying stage, gradually varying stage at the pre-peak and suddenly varying stage at the post peak stage.The axial compressive stress in the bolt is mainly induced by the moment. Thus, in most cases the axial compressive stress is distributed on one side of the bolt. For axial stresses, induced by the axial force and the bending moment at the post-peak stage, three types of changing are observed, viz. increasingincreasing type, decreasing-increasing type and increasing-decreasing type. The stress characteristics of the bolt section in the weak interlayer are significantly different from those in the hard rock. The failure models of the anchored bolt are tensile failure and shear failure, respectively. The bolt not only provides constraints on the free surface of the rock mass, but also resists the axial and lateral loading by the bending moment. This study provides valuable guidelines for bolting support design and its safety assessment.
基金financially supported by the National Natural Science Foundation of China (Nos. 51474188, 51074140 and 51310105020)the Natural Science Foundation of Hebei Province (No. E2014203012)the Program for Taihang Scholars
文摘For a soft rock tunnel under high stress in jointed and swell soft rock （HJS）, two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC20, and the deformation effects of the two construction schemes were verified by field tests. Based on engineer- ing geological investigation and mechanical analysis of large deformations, the complex deformation mechanisms of stress expansion and structural deformation of the soft rock tunnel were confirmed, and support countermeasures from the complex deformation mechanism converted to a single type were proposed, and the support parameters were optimized by field tests. These technologies were proved by engineering practice, which produced significant technical and economic benefits.
基金supported by the National Basic Research Program of China (No.2006CB202200)the Ministry of Education Innovation Team Project (No. IRT0656)+2 种基金the Central University Basic Research Special Fund Operating Expense (No.2009QL06)the New Century Excellent Talents Support Projects of Ministry of Education (No.NCET-08-0833)the National Natural Science Foundation of China (No.41040027)
文摘Geomechanics in deep mines becomes more complex and structural support in soft rock can be very difficult.Highly stressed soft rock subject to expansion deformation is particularly difficult to control.The Tiefa Coal Industry Group Daqiang Coal Mine is used as an example.A ventilation shaft,à550 horsehead,is located in tertiary soft rock.Analysis of the reasons for deformation shows an intumescent rock,which is easily damaged.Field observations and theoretical analysis led to a design capable of stabilizing the rock.A combination of spray,anchors,anchor bolts,and soft corner coupled truss supports allowed the deformation to be controlled.This provides a model for similar designs when support of a horsehead roadway is required.
基金Supported by Jiangsu Major Research and Development(Social Development)Project of China(Grant No.BE2016802).
文摘Large pressure equipment needs to be tested regularly to ensure safe operation;wall-climbing robots can carry the necessary tools to inspect spherical tanks,such as cameras and non-destructive testing equipment.However,a wall-climbing robot inside a spherical tank cannot be accurately positioned owing to the particularity of the spherical tank structure.This paper proposes a passive support and positioning mechanism fixed in a spherical tank to improve the adsorption capacity and positioning accuracy of the inspection robot.The main body of the mechanism was designed as a truss composed of carbon fiber telescopic rods and can work in spherical tanks with diameters of 4.6-15.7 m.The structural strength,stiffness,and stability of the mechanism are analyzed via force and deformation simulations.By constructing a mathematical model of the support and positioning mechanism,the influence of structural deformation on the supporting capacity is analyzed and calculated.The robot positioning method based on the support and positioning mechanism can effectively locate the robot inside a spherical tank.Experiments verified the support performance and robot positioning accuracy of the mechanism.This research proposes an auxiliary support and positioning mechanism for a detection robot inside a spherical tank,which can effectively improve the positioning accuracy of the robot and meet the robotic inspection requirements.
文摘In order to enhance the sealing quality and assemble efficiency of hydraulic supports, the evaluation system for the sealability of the hydraulic support and jack＇s seals was established through the testing and experimenting technology in respects, such as seals＇ dimensions, reasonable amounts of compression, sealability, life, resistance to pressure, etc. Through life detecting test of the seal, found the longest life seal ring under the same conditions, and through the reciprocating test of the hydraulic support, found the most appropriate amount of interference between the groove and the seal ring, thus, to decrease the leakage and extend the life span of the hydraulic support.
基金Financial support for this work, provided by the National Natural Science Foundation of China (No. 51174195)the Graduate Student Scientific Research Innovation Project of the Jiangsu Province Ordinary University (No. CXZZ12_0954)the Research Foundation of the State Key Laboratory of Coal Resources and Mine Safety (No. SKLCRSM08X04)
文摘In order to avoid the deep-well oil shale roadway being deformed, damaged, or difficult to maintain after excavating and supporting in Haishiwan coal mine, this paper has analyzed the characteristics of the deformed roadway and revealed its failure mechanism by taking comprehensively the methods of field geological investigation, displacement monitoring of surrounding rock, rock properties and hydration properties experiments and field application tests. Based on this work, the high-resistance controlled yielding supporting principle is proposed, which is： to ＂resist＂ by high pre-tightening force and high stiff- ness in the early stage, to ＂yield＂ by making use of the controlled deformation of a yielding tube in the middle stage, and to ＂fix＂ by applying total-section Gunite in the later stage. A high-resistance controlled yielding supporting technique of ＂high pre-tightening force yielding anchor bolt ＋ small-bore pre-tight- ening force anchor cable ＋ rebar ladder beam ＋ rhombic metal mesh ＋ lagging gunite＂ has been estab- lished, and industrial on site testing implemented. The practical results show that the high-resistance controlled yielding supporting technique can effectively control the large deformation and long-time rheology of deep-well oil shale roadways and can provide beneficial references for the maintenance of other con-generic roadways.Deep-well Oil shale
文摘This paper takes No.52 return uphill roadway of Yangquhe coal mine as a research project. Based on the research, especially its geological condition, indoor experiments, numerical simulation and theoretical analysis were employed to determine the difficult coefficients of Yangquhe project. By using these means,the difficult coefficients of the deep rock engineering were determined. From a study of the effects of crustal stress and the roof mechanism on roadway stability, the transformation mechanism in Yangquhe coal mine has been determined. As a result of this research, the interactive support technology of prestressed cable mesh was developed and the technology tested in mining engineering, which proved to be feasible.
基金Supported by the Health and Family Planning Commission of Shenzhen Municipality,No.SZLY2018024and Sanming Project of Medicine in Shenzhen,No.SZSM201512031.
文摘BACKGROUND Coronavirus disease 2019(COVID-19)severity is classified as asymptomatic,mild,moderate,severe,and critical.Mild cases account for a large percentage of cases in the epidemic and typically exhibit a favorable prognosis.However,a 49%-67%mortality is noted in critical cases.No COVID-19-specific drug has been reported to date,and symptomatic and optimal supportive care,including oxygenation,anti-coinfection treatments,and ventilation,represent the mainstay of treatment for this disease,especially in critical patients.CASE SUMMARY In the above-mentioned context,we share our experience with the treatment of one critical COVID-19 case and review the relevant literature.CONCLUSION Timely tracheal intubation,reasonable mechanical ventilation support,appropriate anti-infection treatment,and early anticoagulation and immunity support are key factors in the successful treatment of this case.
文摘According to the research results in world, the paper comprehensively analyzed and gave a demonstration of mechanism of single-truss and its stressing advantage. Comparison and analysis effect were given to single-truss and bolting supporting. By the way of element simulation. The paper shows that single truss supporting have better effect to bolting supporting to improving the stress condition of surrounding rocks, controlling the surrounding rocks plastic failure development zone and deformation effect of surrounding rocks, which provided the elementary theory basis to the research, experiment and expanding the single-truss bolting technology in colliery.
文摘The truss cable support technology was put forward to control the large mining height and composite mudstone strata roadway. This technique makes the steady rock in roadway slantwise top be anchor points, makes the truss cable be steady support structure through special implement, and supplied rock in anchor area with horizontal and vertical pressure which strengthens the surrounding rock＇s anti-strain capability, so it can solve the support problem in roadway with the large cross section and large mining height with mudstone strata. The support mechanism of truss cable about how to make the soft strata stabilize is analyzed by use of the mechanical method. Based on the mechanism and numerical simulation method, the truss cable support project was designed and used to the large mining setting room in eleventh mining area of Bailong Mine successfully.
基金Supported by the Innovative Talent Funds for Project 985 under Grant No WLYJSBJRCTD201102the Fundamental Research Funds for the Central Universities under Grant No CQDXWL-2013-014+1 种基金the Natural Science Foundation of Chongqing under Grant No CSTC2006BB5240the Program for New Century Excellent Talents in Universities of China under Grant No NCET-07-0903
文摘Support vector regression （SVR） combined with particle swarm optimization for its parameter optimization is employed to establish a model for predicting the Henry constants of multi-walled carbon nanotubes （MWNTs） for adsorption of volatile organic compounds （VOCs）. The prediction performance of SVR is compared with those of the model of theoretical linear salvation energy relationship （TLSER）. By using leave-one-out cross validation of SVR test Henry constants for adsorption of 35 VOCs on MWNTs, the root mean square error is 0.080, the mean absolute percentage error is only 1.19~, and the correlation coefficient （R2） is as high as 0.997. Compared with the results of the TLSER model, it is shown that the estimated errors by SVR are ali smaller than those achieved by TLSER. It reveals that the generalization ability of SVR is superior to that of the TLSER model Meanwhile, multifactor analysis is adopted for investigation of the influences of each molecular structure descriptor on the Henry constants. According to the TLSER model, the adsorption mechanism of adsorption of carbon nanotubes of VOCs is mainly a result of van der Waals and interactions of hydrogen bonds. These can provide the theoretical support for the application of carbon nanotube adsorption of VOCs and can make up for the lack of experimental data.
文摘In recent years, human society has achieved rapid development and progress, in this process, a large amount of energy is developed and utilized, which eventually leads to the problem of energy shortage. In order to effectively alleviate the current energy shortage problem, people have invested a lot of manpower and material resources in the research and development of new energy, which has laid a solid foundation for the sustainable and stable development of human society. In terms of today's actual situation, global oil and coal energy accounts for a large proportion in the total energy, but after being exploited and utilized in large quantities, it shows a trend of decline year by year. Renewable and environmental protection characteristics of new energy make it the most potential energy at present. We believe that new energy will inevitably trigger an industrial revolution in the future. In order to effectively promote the sustainable and stable development of the new energy industry, the most important thing is to obtain the support of the continuous market. Simply relying on government subsidies is unable to meet the actual needs of the industry development, so we need to look for more additional capital market support. Although the development of China's new energy industry has reached a high level in the whole world, photovoltaic power generation accounts for 30 percent of the world's total, the industrial development speed has exceeded the United States and Germany, the market has a good prospect in the future. However, long-term dependence on government subsidies leads to the lack of driving force for industrial development. Therefore, we urgently need the necessary support from the capital market to alleviate the above problems. In view of this, this paper mainly focuses on the capital market supporting mechanism for the development of new energy industry to carry out practical analysis and research, hoping to be helpful to the healthy and stable development of China's new energy field.
文摘The close coal seam group exists in Datong, Xishan, Huozhou, Fenxi and other coalfields. At the same time, the strata between coal seams are usually soft rock composite strata and soft rock composite strata. Because the coal seam is affected by the mine pressure, the integrity of the original surrounding rock cannot be guaranteed, and the joint and crack of the composite weak roof of the lower coal seam are damaged, so it is difficult to control the roadway roof during the excavation, which leads to the phenomenon of spalling or roof fall, and brings difficulties to the periodic maintenance and support work. Based on the analysis of the transportation roadway in coal mining face, the roadway layout and roof support under the condition of short distance coal seam goaf and compound soft roof are studied, so as to provide help for the safe construction of coal mining face under such conditions.
文摘Electrical storm(ES) is a medical emergency characterized by repetitive episodes of sustained ventriculararrhythmias(VAs) in a limited amount of time(at least 3 within a 24-h period) leading to repeated appropriate implantable cardioverter defibrillator therapies. The occurrence of ES represents a major turning point in the natural history of patients with structural heart disease being associated with poor short-and longterm survival particularly in those with compromised left ventricular ejection fraction(LVEF) that can develop hemodynamic decompensation and multi-organ failure. Management of ES is challenging with limited available evidence coming from small retrospective series and a substantial lack of randomized-controlled trials. In general, a multidisciplinary approach including medical therapies such as anti-arrhythmic drugs, sedation, as well as interventional approaches like catheter ablation, may be required. Accurate patient risk stratification at admission for ES is pivotal and should take into account hemodynamic tolerability of VAs as well as comorbidities like low LVEF, advanced NYHA class and chronic pulmonary disease. In high risk patients, prophylactic mechanical circulatory support with left ventricular assistance devices or extracorporeal membrane oxygenation should be considered as bridge to ablation and recovery. In the present manuscript we review the available strategies for management of ES and the evidence supporting them.
