BACKGROUND Sudden death is unanticipated,non-violent death taking place within the first 24 h after the onset of symptoms.It is a major public health problem worldwide.Moreover,the effects of living at moderate altitu...BACKGROUND Sudden death is unanticipated,non-violent death taking place within the first 24 h after the onset of symptoms.It is a major public health problem worldwide.Moreover,the effects of living at moderate altitude on mortality are poorly understood.AIM To retrospectively report the frequency and the main causes of sudden deaths in relation to total deaths at Asir Central Hospital,2255 m above sea level,in the southern region of Saudi Arabia over a period of 4 years from 2013 to 2016.METHODS The medical records of 1821 deaths were examined and showed 353 cases(19.4%)of sudden death.RESULTS The highest incidence of sudden death was among the elderly(51%),whereas,the lowest was among children and adolescents(6.5%).With regard to gender,the incidence of sudden death was higher in males(54.4%)compared to 45.6% in females.In this study,we found that the most common direct causes of sudden death were cardiovascular diseases(29.2%),respiratory disease(22.7%),infectious disease(12.2%),cancer(9.4%)and hematological diseases(6.2%).With respect to seasonal variation,the highest incidence was during winter(31.32%)followed by summer(25.8%).CONCLUSION The results of this study will help emergency physicians and health care providers to exercise due care to reduce the incidence of sudden death and raise public awareness about the impact of sudden death.展开更多
In this paper,we investigate the dynamical behaviour of entanglement in terms of concurrence in a bipartite system subjected to an external magnetic field under the action of dissipative environments in the extended W...In this paper,we investigate the dynamical behaviour of entanglement in terms of concurrence in a bipartite system subjected to an external magnetic field under the action of dissipative environments in the extended Werner-like initial state.The interesting phenomenon of entanglement sudden death as well as sudden birth appears during the evolution process.We analyse in detail the effect of the purity of the initial entangled state of two qubits via Heisenberg XY interaction on the apparition time of entanglement sudden death and entanglement sudden birth.Furthermore,the conditions on the conversion of entanglement sudden death and entanglement sudden birth can be generalized when the initial entangled state is not pure.In particular,a critical purity of the initial mixed entangled state exists,above which entanglement sudden birth vanishes while entanglement sudden death appears.It is also noticed that stable entanglement,which is independent of different initial states of the qubits (pure or mixed state),occurs even in the presence of decoherence.These results arising from the combination of the extended Werner-like initial state and dissipative environments suggest an approach to control and enhance the entanglement even after purity induced sudden birth,death and revival.展开更多
Cardiac Arrest (CA) is a major health problem, due to short and long-term sequel? and to associated mortality. Despite the improvement of out-of-hospital and in-hospital resuscitation manoeuvres, unexpected sudden fat...Cardiac Arrest (CA) is a major health problem, due to short and long-term sequel? and to associated mortality. Despite the improvement of out-of-hospital and in-hospital resuscitation manoeuvres, unexpected sudden fatal events occur. The authors reported the features of a series of sudden death (SD) cases where cardiopulmonary resuscitation (CPR) was performed. Files of 1053 medico-legal autopsies, from victims aged ≥18 years-old, were reviewed. Cardiac Arrest leading to Sudden Death were found in 477 cases (45.3%), but only 199 (42%) of these had been submitted to resuscitation manoeuvres. There was an elderly male predominance. Both non-cardiac and cardiac CA/SD causes were present, despite the higher coronary artery disease incidence. Both out-of-hospital and in-hospital events took place. Age, severity of the disease, comorbidities and predominance of out-of-hospital CA were obstacles to successful CPR, leading to SD. Knowing the population characteristics may help to improve Emergency Assistance.展开更多
We report an acute case of a native man from Bolivia suffered from cephalalgia which rapidly worsened and ended in his sudden and unexpected death.Magnetic resonance imaging(MRI) of the brain was obtained.Features dem...We report an acute case of a native man from Bolivia suffered from cephalalgia which rapidly worsened and ended in his sudden and unexpected death.Magnetic resonance imaging(MRI) of the brain was obtained.Features demonstrated on brain MRI scan were consistent with a diagnosis of neurocysticercosis(NCC).An autopsy showed the presence of intraventricular Taenia solium(T.solium) cysts which caused blockage of cerebrospinal fluid and secondary hydrocephalus.Due to the increasing travel movements of people neurocysticercosis must be considered as a cause of unexplained sudden death.展开更多
The influences of dipole-dipole interaction and detuning on the entanglement between two atoms with different initial tripartite entangled W-like states in the Tavis-Cummings model have been investigated by means of W...The influences of dipole-dipole interaction and detuning on the entanglement between two atoms with different initial tripartite entangled W-like states in the Tavis-Cummings model have been investigated by means of Wootters' concurrence,respectively.The results show that the entanglement between the two atoms can be enhanced via appro-priately tuning the strength of dipole-dipole interaction of two atoms or the detunings between atom and cavity,and the so-called sudden death effect can be weakened simultaneously.展开更多
The dynamics of distillability entanglement between qutrit-qutrit systems interacting with a thermal reservoir is investigated in this paper.We discovered an interesting phenomenon that under a thermal reservoir certa...The dynamics of distillability entanglement between qutrit-qutrit systems interacting with a thermal reservoir is investigated in this paper.We discovered an interesting phenomenon that under a thermal reservoir certain initially prepared free-entangled states become bound-entangled states in a finite time,which is called distillability sudden death(DSD).We use a realignment criterion to measure the nine-dimensional density matrix of the entanglement.Moreover,we analyze some other parameters to investigate the effects to the systems.Explanations are then given.展开更多
This paper demonstrates that multipartite Bell-inequality violations can be fully destroyed in a finite time in three-qubit states coupled to a general XY spin-chain with a three-site interaction environment.The Mermi...This paper demonstrates that multipartite Bell-inequality violations can be fully destroyed in a finite time in three-qubit states coupled to a general XY spin-chain with a three-site interaction environment.The Mermin-Ardehali-Belinksii-Klyshko inequality is used to detect the degree of nonlocality,as measured by the extent of their violations.The effects of system-environment couplings,the size of degrees of freedom of the environment and the strength of the three-site interaction on the Bell-inequality violations are given.The results indicate that the Bell-inequality violations of the tripartite states will be completely destroyed by decoherence under certain conditions for the GHZ state.The decoherence-free subspaces of our model are identified and the entanglement of quantum states is also discussed.展开更多
It is never an easy thing to diagnose heart vascular disease only depending on the unenhanced postmortem computed tomography(PMCT).This article reported a case of sudden natural death after the complaint of anterior c...It is never an easy thing to diagnose heart vascular disease only depending on the unenhanced postmortem computed tomography(PMCT).This article reported a case of sudden natural death after the complaint of anterior chest pain in which coronary artery calcification(CAC) was clearly displayed using PMCT scan.The entire coronary artery system was almost reconstructed via multiplanar reformation(MPR) and volume-rendering reconstruction(VR),and the total calcium score of the coronary arteries was obtained with CaScoring automatic analysis software.The results showed that CAC was conspicuous;the total calcium score was 640.3,considerably higher than 400.The pulmonary ground-glass opacity(GGO) and small amount of fluid both in the subglottic trachea and main bronchi were also found.The imaging results confirmed those of autopsy.In addition,the results concluded that PMCT might serve as an invaluable adjunct to the classic autopsy procedure.展开更多
Introduction Leukem ia is a hem atologic neoplasm characterized by potential infectious and hem orrhagic com plications In adult patients with acute leukem ia,in fection is the most com m on com plication.Imtrcra nial...Introduction Leukem ia is a hem atologic neoplasm characterized by potential infectious and hem orrhagic com plications In adult patients with acute leukem ia,in fection is the most com m on com plication.Imtrcra nial hem orrhage (ICH) is the second most common com plication.H ow ever,ICH has been identified as the m ajor cause of m orbidity and m ortaliity in pa tients with leukem ia[1-6].A num ber of case ceports ascribed the death of leukem ic patients due to hem orrhge of the supratentorial and infratentorial brain,basal ganglia,and cerebellum [2,7-9].However,few cases have reported on brainstem hem orrhage.The current case report involved a young wom an who died of brainstem hem orrhage due to acute leukem ia,discussing the pathophysiologic m echanism underly ing ICH.Futhherm ore,the risk factors were specified,w ith a provision of suggestions to forensic pathologists in handling deaths associated w ith ICH,especially sudden unexpected deaths.展开更多
We investigate the entanglement dynamics of two initially entangled atoms each interacting with a thermal field.We show that the two entangled atoms become completely disentangled in a finite time and that the lost in...We investigate the entanglement dynamics of two initially entangled atoms each interacting with a thermal field.We show that the two entangled atoms become completely disentangled in a finite time and that the lost information cannot return to the atomic system when the mean photon number of the thermal field exceeds a critical value (3.3584),even though the whole system is lossless.Then we study how the detuning between the atomic transition frequency and the field frequency and the disparity between two coupling rates would affect the evolution of the entanglement of the atomic system.展开更多
In this paper, we investigate the entanglement of two qubits coupled collectively to a common thermal environment and find that the the collective decay can lead to a revival of the entanglement that has already been ...In this paper, we investigate the entanglement of two qubits coupled collectively to a common thermal environment and find that the the collective decay can lead to a revival of the entanglement that has already been destroyed. We also show that the ability of the system to revival entanglement relies on the mean photon number of the thermal environment and the degree of entanglement of the initial state.展开更多
In this paper,we study the entanglement dynamics of two-spin Heisenberg XYZ model with the Dzialoshinskii-Moriya (DM) interaction.The system is initially prepared in the Werner state.The effects of purity of the initi...In this paper,we study the entanglement dynamics of two-spin Heisenberg XYZ model with the Dzialoshinskii-Moriya (DM) interaction.The system is initially prepared in the Werner state.The effects of purity of the initial state and DM coupling parameter on the evolution of entanglement are investigated.The necessary and sufficient condition for the appearance of the entanglement sudden death (ESD) phenomenon has been deduced.The result shows that the ESD always occurs if the initial state is sufficiently impure for the given coupling parameter or the DM interaction is sufficiently strong for the given initial state.Moreover,the critical values of them are calculated.展开更多
We investigate the dynamics of the entanglement and quantum discord of two qubits in liquid state homonuclear nuclear magnetic resonance. Applying a phenomenological description for nuclear magnetic resonance under a ...We investigate the dynamics of the entanglement and quantum discord of two qubits in liquid state homonuclear nuclear magnetic resonance. Applying a phenomenological description for nuclear magnetic resonance under a relaxation process, and taking a group of typical parameters of nuclear magnetic resonance, we show that when a zero initial state experiences a relaxation process, its entanglement disappears completely after a sequence of so-called sudden deaths and revivals, while the quantum discord retains remarkable values after a sequence of oscillations. That is to say, the quantum discord is more robust than entanglement.展开更多
We demonstrate that multipartite Bell-inequalities violations can be fully destroyed in finite time in three-qubit states under a quantum-critical environment, which is an Ising model in a transverse field. We use the...We demonstrate that multipartite Bell-inequalities violations can be fully destroyed in finite time in three-qubit states under a quantum-critical environment, which is an Ising model in a transverse field. We use the Mermin-Ardehali-Belinksii-Klyshko (MABK) inequality to detect the degree of nonlocality as measured by the extent of their violations. The effects of system-environment couplings, the size of degrees of freedom of environment and the strength of transverse field on the Bell-inequality violations are given for two different initial states, namely, the W class and GHZ class states. The results indicate that the Bell-inequality violations of the tripartite states will be completely destroyed by the decoherence under certain conditions.展开更多
We examine the entanglement dynamics between two strongly driven atoms off-resonantly coupled with a singlemode cavity via the two-photon process with the help of negativity in two different types of initial states.Th...We examine the entanglement dynamics between two strongly driven atoms off-resonantly coupled with a singlemode cavity via the two-photon process with the help of negativity in two different types of initial states.The results show that entanglement sudden death may occur under both the above conditions and the sudden death effect can be monitored by modulating the atom–cavity detunings.Furthermore,we also find an atomic decoherence-free subspace so that the initial entanglement between two atoms remains invariable in application.展开更多
文摘BACKGROUND Sudden death is unanticipated,non-violent death taking place within the first 24 h after the onset of symptoms.It is a major public health problem worldwide.Moreover,the effects of living at moderate altitude on mortality are poorly understood.AIM To retrospectively report the frequency and the main causes of sudden deaths in relation to total deaths at Asir Central Hospital,2255 m above sea level,in the southern region of Saudi Arabia over a period of 4 years from 2013 to 2016.METHODS The medical records of 1821 deaths were examined and showed 353 cases(19.4%)of sudden death.RESULTS The highest incidence of sudden death was among the elderly(51%),whereas,the lowest was among children and adolescents(6.5%).With regard to gender,the incidence of sudden death was higher in males(54.4%)compared to 45.6% in females.In this study,we found that the most common direct causes of sudden death were cardiovascular diseases(29.2%),respiratory disease(22.7%),infectious disease(12.2%),cancer(9.4%)and hematological diseases(6.2%).With respect to seasonal variation,the highest incidence was during winter(31.32%)followed by summer(25.8%).CONCLUSION The results of this study will help emergency physicians and health care providers to exercise due care to reduce the incidence of sudden death and raise public awareness about the impact of sudden death.
基金Project supported by the National Natural Science Foundation,China (Grant No.10904033)the Natural Science Foundation of Hubei Province,China (Grant No.2009CDA145)+1 种基金the Science Foundation of the Educational Commission of Hubei Province,China (Grant No.D20092204)the Postgraduate Programme of Hubei Normal University of China (Grant No.2007D20)
文摘In this paper,we investigate the dynamical behaviour of entanglement in terms of concurrence in a bipartite system subjected to an external magnetic field under the action of dissipative environments in the extended Werner-like initial state.The interesting phenomenon of entanglement sudden death as well as sudden birth appears during the evolution process.We analyse in detail the effect of the purity of the initial entangled state of two qubits via Heisenberg XY interaction on the apparition time of entanglement sudden death and entanglement sudden birth.Furthermore,the conditions on the conversion of entanglement sudden death and entanglement sudden birth can be generalized when the initial entangled state is not pure.In particular,a critical purity of the initial mixed entangled state exists,above which entanglement sudden birth vanishes while entanglement sudden death appears.It is also noticed that stable entanglement,which is independent of different initial states of the qubits (pure or mixed state),occurs even in the presence of decoherence.These results arising from the combination of the extended Werner-like initial state and dissipative environments suggest an approach to control and enhance the entanglement even after purity induced sudden birth,death and revival.
文摘Cardiac Arrest (CA) is a major health problem, due to short and long-term sequel? and to associated mortality. Despite the improvement of out-of-hospital and in-hospital resuscitation manoeuvres, unexpected sudden fatal events occur. The authors reported the features of a series of sudden death (SD) cases where cardiopulmonary resuscitation (CPR) was performed. Files of 1053 medico-legal autopsies, from victims aged ≥18 years-old, were reviewed. Cardiac Arrest leading to Sudden Death were found in 477 cases (45.3%), but only 199 (42%) of these had been submitted to resuscitation manoeuvres. There was an elderly male predominance. Both non-cardiac and cardiac CA/SD causes were present, despite the higher coronary artery disease incidence. Both out-of-hospital and in-hospital events took place. Age, severity of the disease, comorbidities and predominance of out-of-hospital CA were obstacles to successful CPR, leading to SD. Knowing the population characteristics may help to improve Emergency Assistance.
文摘We report an acute case of a native man from Bolivia suffered from cephalalgia which rapidly worsened and ended in his sudden and unexpected death.Magnetic resonance imaging(MRI) of the brain was obtained.Features demonstrated on brain MRI scan were consistent with a diagnosis of neurocysticercosis(NCC).An autopsy showed the presence of intraventricular Taenia solium(T.solium) cysts which caused blockage of cerebrospinal fluid and secondary hydrocephalus.Due to the increasing travel movements of people neurocysticercosis must be considered as a cause of unexplained sudden death.
基金supported by the National Natural Science Foundation of China (Grant No 60667001)
文摘The influences of dipole-dipole interaction and detuning on the entanglement between two atoms with different initial tripartite entangled W-like states in the Tavis-Cummings model have been investigated by means of Wootters' concurrence,respectively.The results show that the entanglement between the two atoms can be enhanced via appro-priately tuning the strength of dipole-dipole interaction of two atoms or the detunings between atom and cavity,and the so-called sudden death effect can be weakened simultaneously.
基金Project supported by the National Natural Science Foundation of China (Grant No. 11074072)
文摘The dynamics of distillability entanglement between qutrit-qutrit systems interacting with a thermal reservoir is investigated in this paper.We discovered an interesting phenomenon that under a thermal reservoir certain initially prepared free-entangled states become bound-entangled states in a finite time,which is called distillability sudden death(DSD).We use a realignment criterion to measure the nine-dimensional density matrix of the entanglement.Moreover,we analyze some other parameters to investigate the effects to the systems.Explanations are then given.
基金Project supported by the National Natural Science Foundation of China (Grant No.11004050)the Scientific Research Fund of Hunan Provincial Education Department of China (Grant Nos.+3 种基金 09A013 and 10B013)the Science and Technology Research Foundation of Hunan Province of China (Grant No.2010FJ4120)the Excellent Talents Program of Hengyang Normal University of China (Grant No.2010YCJH01)the Science Foundation of Hengyang Normal University of China (Grant Nos.10A46 and 10B69)
文摘This paper demonstrates that multipartite Bell-inequality violations can be fully destroyed in a finite time in three-qubit states coupled to a general XY spin-chain with a three-site interaction environment.The Mermin-Ardehali-Belinksii-Klyshko inequality is used to detect the degree of nonlocality,as measured by the extent of their violations.The effects of system-environment couplings,the size of degrees of freedom of the environment and the strength of the three-site interaction on the Bell-inequality violations are given.The results indicate that the Bell-inequality violations of the tripartite states will be completely destroyed by decoherence under certain conditions for the GHZ state.The decoherence-free subspaces of our model are identified and the entanglement of quantum states is also discussed.
基金This study was funded Natural Science Foundation would like to thank Prof. technical assistance, who Huadong Hospital, Shangh by the Council of National of China (GY2012-1). We ZHANG Guo-zhen for his works in the CT room of ai, China.
文摘It is never an easy thing to diagnose heart vascular disease only depending on the unenhanced postmortem computed tomography(PMCT).This article reported a case of sudden natural death after the complaint of anterior chest pain in which coronary artery calcification(CAC) was clearly displayed using PMCT scan.The entire coronary artery system was almost reconstructed via multiplanar reformation(MPR) and volume-rendering reconstruction(VR),and the total calcium score of the coronary arteries was obtained with CaScoring automatic analysis software.The results showed that CAC was conspicuous;the total calcium score was 640.3,considerably higher than 400.The pulmonary ground-glass opacity(GGO) and small amount of fluid both in the subglottic trachea and main bronchi were also found.The imaging results confirmed those of autopsy.In addition,the results concluded that PMCT might serve as an invaluable adjunct to the classic autopsy procedure.
基金This study was funded by Natural Science Foundation of China
文摘Introduction Leukem ia is a hem atologic neoplasm characterized by potential infectious and hem orrhagic com plications In adult patients with acute leukem ia,in fection is the most com m on com plication.Imtrcra nial hem orrhage (ICH) is the second most common com plication.H ow ever,ICH has been identified as the m ajor cause of m orbidity and m ortaliity in pa tients with leukem ia[1-6].A num ber of case ceports ascribed the death of leukem ic patients due to hem orrhge of the supratentorial and infratentorial brain,basal ganglia,and cerebellum [2,7-9].However,few cases have reported on brainstem hem orrhage.The current case report involved a young wom an who died of brainstem hem orrhage due to acute leukem ia,discussing the pathophysiologic m echanism underly ing ICH.Futhherm ore,the risk factors were specified,w ith a provision of suggestions to forensic pathologists in handling deaths associated w ith ICH,especially sudden unexpected deaths.
基金Project supported by the National Natural Science Foundation of China (Grant No.10974028)the Natural Science Foundation of Fujian Province of China (Grant No.2009J06002)the Funds from the State Key Laboratory Breeding Base of Photocatalysis
文摘We investigate the entanglement dynamics of two initially entangled atoms each interacting with a thermal field.We show that the two entangled atoms become completely disentangled in a finite time and that the lost information cannot return to the atomic system when the mean photon number of the thermal field exceeds a critical value (3.3584),even though the whole system is lossless.Then we study how the detuning between the atomic transition frequency and the field frequency and the disparity between two coupling rates would affect the evolution of the entanglement of the atomic system.
基金supported by the National Natural Science Foundation of China (Grant No.10374025)Hunan Provincial Natural Science Foundation of China (Grant No.06JJ4003)the Major Program for the Research Foundation of Education Bureau of Hunan Province,China (Grant No.08A015)
文摘In this paper, we investigate the entanglement of two qubits coupled collectively to a common thermal environment and find that the the collective decay can lead to a revival of the entanglement that has already been destroyed. We also show that the ability of the system to revival entanglement relies on the mean photon number of the thermal environment and the degree of entanglement of the initial state.
基金supported by National Natural Science Foundation of China (Grant No 10374007)
文摘In this paper,we study the entanglement dynamics of two-spin Heisenberg XYZ model with the Dzialoshinskii-Moriya (DM) interaction.The system is initially prepared in the Werner state.The effects of purity of the initial state and DM coupling parameter on the evolution of entanglement are investigated.The necessary and sufficient condition for the appearance of the entanglement sudden death (ESD) phenomenon has been deduced.The result shows that the ESD always occurs if the initial state is sufficiently impure for the given coupling parameter or the DM interaction is sufficiently strong for the given initial state.Moreover,the critical values of them are calculated.
基金supported by the Fundamental Research Funds for the Central Universities of China (Grant No. 2010scu23002)
文摘We investigate the dynamics of the entanglement and quantum discord of two qubits in liquid state homonuclear nuclear magnetic resonance. Applying a phenomenological description for nuclear magnetic resonance under a relaxation process, and taking a group of typical parameters of nuclear magnetic resonance, we show that when a zero initial state experiences a relaxation process, its entanglement disappears completely after a sequence of so-called sudden deaths and revivals, while the quantum discord retains remarkable values after a sequence of oscillations. That is to say, the quantum discord is more robust than entanglement.
基金Project supported by the Key Scientific Research Fund of the Education Department of Hunan Province of China (Grant No. 09A013)
文摘We demonstrate that multipartite Bell-inequalities violations can be fully destroyed in finite time in three-qubit states under a quantum-critical environment, which is an Ising model in a transverse field. We use the Mermin-Ardehali-Belinksii-Klyshko (MABK) inequality to detect the degree of nonlocality as measured by the extent of their violations. The effects of system-environment couplings, the size of degrees of freedom of environment and the strength of transverse field on the Bell-inequality violations are given for two different initial states, namely, the W class and GHZ class states. The results indicate that the Bell-inequality violations of the tripartite states will be completely destroyed by the decoherence under certain conditions.
基金Project supported by the National Natural Science Foundation of China (Grant No 60667001)the Education Foundation of Yanbian University of China
文摘We examine the entanglement dynamics between two strongly driven atoms off-resonantly coupled with a singlemode cavity via the two-photon process with the help of negativity in two different types of initial states.The results show that entanglement sudden death may occur under both the above conditions and the sudden death effect can be monitored by modulating the atom–cavity detunings.Furthermore,we also find an atomic decoherence-free subspace so that the initial entanglement between two atoms remains invariable in application.