BACKGROUND Transfemoral aortic valve replacement(TAVR)is the standard treatment for elderly patients with aortic valve stenosis.Although safe and well-established,there is a risk of intraprocedural hemodynamic instabi...BACKGROUND Transfemoral aortic valve replacement(TAVR)is the standard treatment for elderly patients with aortic valve stenosis.Although safe and well-established,there is a risk of intraprocedural hemodynamic instability and silent cerebral embolism,which can lead to a decline in neurocognitive function and dementia.In clinical practice,comprehensive cognitive testing is difficult to perform.AI-assisted digital applications may help to optimize diagnosis and monitoring.METHODS Neurocognitive function was assessed by validated psychometric tests using“Δelta-App”,which uses artificial intelligence and computational linguistic methods for extraction and analysis.Memory function was assessed using the‘Consortium to Establish a Registry for Alzheimer’s Disease’(CERAD)word list and digit span task(DST)before TAVR and before hospital discharge.The study is registered in the German Register of Clinical Trials(https://drks.de/search/de/trial/DRKS00020813).RESULTS From October 2020 until March 2022,141 patients were enrolled at University Hospital Heart Centre Brandenburg.Mean age was 81±6 years,42.6%were women.Time between the pre-and post-interventional test was on average 6±3 days.Memory function before TAVR was found to be below average in relation to age and educational level.The pre-post TAVR comparison showed significant improvements in the wordlist repeat,P<0.001 and wordlist recall test of CERAD,P<0.001.There were no changes in the digital span test.CONCLUSIONS Despite impaired preoperative memory function before TAVR,no global negative effect on memory function after TVAR was detected.The improvements shown in the word list test should be interpreted as usual learning effects in this task.展开更多
A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected...A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during January 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the order of Na <Ca <Mg <K and those of anions were in the order of Cl <HCO3 <SO4 <CO3, respectively. This was in agreement with the water types, Na-Cl and Na-Ca-HCO3, determined by the Piper plot. High concentrations of the ions Na, Cl and SO4 were recorded near the tanneries that operate within the study area. While the elevated concentrations of HCO3 and F were observed away from the tanneries. This peculiar hydrochemical behaviour suggests that the chemistry of water is predominantly influenced by tannery effluents and weathering of silicate minerals. Results of the linear regression model yielded 11 regression equations for the 5 most correlated parameters. A dendrogram from the cluster analysis showed 2 major clusters representing the influence of tanneries and geological formations in the study area, which confirmed the results of major ion chemistry.展开更多
The need of communication protocols in today’s environment increases as much as the network explores. Many new kinds of protocols, e.g. for information sharing, security, etc., are being developed day-to-day which of...The need of communication protocols in today’s environment increases as much as the network explores. Many new kinds of protocols, e.g. for information sharing, security, etc., are being developed day-to-day which often leads to rapid, premature developments. Many protocols have not scaled to satisfy important properties like deadlock and livelock freedom, since MDA focuses on the rapid development rather than on the quality of the developed models. In order to fix the above, we introduce a 2-Phase strategy based on the UML state machine and sequence diagram. The state machine is converted into PROMELA code as a protocol model and its properties are derived from the sequence diagram as Linear Temporal Logic (LTL) through automation. The PROMELA code is interpreted through the SPIN model checker, which helps to simulate the behavior of protocol. Later the automated LTL properties are supplemented to the SPIN for the verification of protocol properties. The results are compared with the developed UML model and SPIN simulated model. Our test results impress the designer to verify the expected results with the system design and to identify the errors which are unnoticed during the design phase.展开更多
The integration of surface normals for the purpose of computing the shape of a surface in 3D space is a classic problem in computer vision. However,even nowadays it is still a challenging task to devise a method that ...The integration of surface normals for the purpose of computing the shape of a surface in 3D space is a classic problem in computer vision. However,even nowadays it is still a challenging task to devise a method that is flexible enough to work on non-trivial computational domains with high accuracy, robustness,and computational efficiency. By uniting a classic approach for surface normal integration with modern computational techniques, we construct a solver that fulfils these requirements. Building upon the Poisson integration model, we use an iterative Krylov subspace solver as a core step in tackling the task. While such a method can be very efficient, it may only show its full potential when combined with suitable numerical preconditioning and problem-specific initialisation. We perform a thorough numerical study in order to identify an appropriate preconditioner for this purpose.To provide suitable initialisation, we compute this initial state using a recently developed fast marching integrator. Detailed numerical experiments illustrate the benefits of this novel combination. In addition, we show on real-world photometric stereo datasets that the developed numerical framework is flexible enough to tackle modern computer vision applications.展开更多
The paper presents a short overview of the contemporary approaches for calculating welding distortions. In order to meet the existing challenges, an advanced hybrid model for prediction of welding distortions in large...The paper presents a short overview of the contemporary approaches for calculating welding distortions. In order to meet the existing challenges, an advanced hybrid model for prediction of welding distortions in large structures is described. For the purpose of illustrating the capability of this model, a simulation case is put into discussion. The results are validated by comparison with experimental data, as well as with common simulation technique. Analysis of the calculation costs is also presented. The directions for development of calculation technique, based on the presented model, are also suggested.展开更多
基金the Ministry of Science,Research and Cultural Affairs of the State of Brandenburg and the MHB publication fund supported by DFG.Jonathan Nübel declares that this work is supported by a research grant of the German Cardiac Society(DGK)the Ethics committee of the Brandenburg Medical School(MHB)E-01-20191006.
文摘BACKGROUND Transfemoral aortic valve replacement(TAVR)is the standard treatment for elderly patients with aortic valve stenosis.Although safe and well-established,there is a risk of intraprocedural hemodynamic instability and silent cerebral embolism,which can lead to a decline in neurocognitive function and dementia.In clinical practice,comprehensive cognitive testing is difficult to perform.AI-assisted digital applications may help to optimize diagnosis and monitoring.METHODS Neurocognitive function was assessed by validated psychometric tests using“Δelta-App”,which uses artificial intelligence and computational linguistic methods for extraction and analysis.Memory function was assessed using the‘Consortium to Establish a Registry for Alzheimer’s Disease’(CERAD)word list and digit span task(DST)before TAVR and before hospital discharge.The study is registered in the German Register of Clinical Trials(https://drks.de/search/de/trial/DRKS00020813).RESULTS From October 2020 until March 2022,141 patients were enrolled at University Hospital Heart Centre Brandenburg.Mean age was 81±6 years,42.6%were women.Time between the pre-and post-interventional test was on average 6±3 days.Memory function before TAVR was found to be below average in relation to age and educational level.The pre-post TAVR comparison showed significant improvements in the wordlist repeat,P<0.001 and wordlist recall test of CERAD,P<0.001.There were no changes in the digital span test.CONCLUSIONS Despite impaired preoperative memory function before TAVR,no global negative effect on memory function after TVAR was detected.The improvements shown in the word list test should be interpreted as usual learning effects in this task.
文摘A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during January 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the order of Na <Ca <Mg <K and those of anions were in the order of Cl <HCO3 <SO4 <CO3, respectively. This was in agreement with the water types, Na-Cl and Na-Ca-HCO3, determined by the Piper plot. High concentrations of the ions Na, Cl and SO4 were recorded near the tanneries that operate within the study area. While the elevated concentrations of HCO3 and F were observed away from the tanneries. This peculiar hydrochemical behaviour suggests that the chemistry of water is predominantly influenced by tannery effluents and weathering of silicate minerals. Results of the linear regression model yielded 11 regression equations for the 5 most correlated parameters. A dendrogram from the cluster analysis showed 2 major clusters representing the influence of tanneries and geological formations in the study area, which confirmed the results of major ion chemistry.
文摘The need of communication protocols in today’s environment increases as much as the network explores. Many new kinds of protocols, e.g. for information sharing, security, etc., are being developed day-to-day which often leads to rapid, premature developments. Many protocols have not scaled to satisfy important properties like deadlock and livelock freedom, since MDA focuses on the rapid development rather than on the quality of the developed models. In order to fix the above, we introduce a 2-Phase strategy based on the UML state machine and sequence diagram. The state machine is converted into PROMELA code as a protocol model and its properties are derived from the sequence diagram as Linear Temporal Logic (LTL) through automation. The PROMELA code is interpreted through the SPIN model checker, which helps to simulate the behavior of protocol. Later the automated LTL properties are supplemented to the SPIN for the verification of protocol properties. The results are compared with the developed UML model and SPIN simulated model. Our test results impress the designer to verify the expected results with the system design and to identify the errors which are unnoticed during the design phase.
文摘The integration of surface normals for the purpose of computing the shape of a surface in 3D space is a classic problem in computer vision. However,even nowadays it is still a challenging task to devise a method that is flexible enough to work on non-trivial computational domains with high accuracy, robustness,and computational efficiency. By uniting a classic approach for surface normal integration with modern computational techniques, we construct a solver that fulfils these requirements. Building upon the Poisson integration model, we use an iterative Krylov subspace solver as a core step in tackling the task. While such a method can be very efficient, it may only show its full potential when combined with suitable numerical preconditioning and problem-specific initialisation. We perform a thorough numerical study in order to identify an appropriate preconditioner for this purpose.To provide suitable initialisation, we compute this initial state using a recently developed fast marching integrator. Detailed numerical experiments illustrate the benefits of this novel combination. In addition, we show on real-world photometric stereo datasets that the developed numerical framework is flexible enough to tackle modern computer vision applications.
文摘The paper presents a short overview of the contemporary approaches for calculating welding distortions. In order to meet the existing challenges, an advanced hybrid model for prediction of welding distortions in large structures is described. For the purpose of illustrating the capability of this model, a simulation case is put into discussion. The results are validated by comparison with experimental data, as well as with common simulation technique. Analysis of the calculation costs is also presented. The directions for development of calculation technique, based on the presented model, are also suggested.
