Objective To describe the clinical characteristics of idiopathic ventricular fibrillation （IVF） with fragmented QRS complex （f-QRS） and J wave in resting electrocardiogram. Methods We reviewed data from 21 case su...Objective To describe the clinical characteristics of idiopathic ventricular fibrillation （IVF） with fragmented QRS complex （f-QRS） and J wave in resting electrocardiogram. Methods We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram （ECG）. All the case subjects were classified among three groups based on the electrocardiographic morphology： group I, both f-QRS and J wave were observed （n = 6）, group II, only J wave was observed （n = 9）, group III, neither f-QRS nor J wave was observed （n = 6）. Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation （VF）, and circumstance of VF were evaluated among the three groups. Results The incidence of index events （syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator （ICD） or pacemakers） was 13.4 ~ 5.6 per-year in group I, 10.8 ~ 3.9 per-year in group II, and 9.8 -4- 4.2 per-year in group HI. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 （95%CI, 1.1-7.9; P = 0.01）. The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. Conclusions This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.展开更多
The possibility of driving poloidal flows by use of ion Bernstein wave is assessed for Heliotron J and EAST devices by means of ray tracing analysis. Sheared poloidal flow is expected to suppress plasma turbulences du...The possibility of driving poloidal flows by use of ion Bernstein wave is assessed for Heliotron J and EAST devices by means of ray tracing analysis. Sheared poloidal flow is expected to suppress plasma turbulences due to the decorrelation of the waves. In Heliotron J and EAST plasma, the rays of Ion Bernstein Wave travel into the central region with oscillations along the magnetic lines of force and their power is absorbed by ions at the cyclotron resonance layers. The momentum input has been estimated by calculating the momentum change of rays and the poloidal flow has been estimated using neoclassical viscosities. The wave momentum changes its sign as it propagates inward, depositing sheared momentum to the plasma, and therefore causes sheared poloidal flows.展开更多
Vasospastic angina is caused by sudden occlusive vasoconstriction of a segment of an epicardial artery, which can present with a wide spectrum of clinical scenario. We report the cases of two patients diagnosed with v...Vasospastic angina is caused by sudden occlusive vasoconstriction of a segment of an epicardial artery, which can present with a wide spectrum of clinical scenario. We report the cases of two patients diagnosed with vasospastic angina, with one of which presenting with sudden cardiac arrest, while the other presenting with a relatively benign syncope. But both of them have J waves formation on ECG during active ischemia. The diagnosis and management of vasospastic angina, as well as the proposed clinical significance of J waves during coro- nary soasm are discussed.展开更多
The complete orbital and spin period evolutions of the double neutron star(NS)system PSR J0737-3039 are simulated from birth to coalescence,which include the two observed radio pulsars classified as primary NS PSR J07...The complete orbital and spin period evolutions of the double neutron star(NS)system PSR J0737-3039 are simulated from birth to coalescence,which include the two observed radio pulsars classified as primary NS PSR J0737-3039 A and companion NS PSR J0737-3039 B.By employing the characteristic age of PSR J0737-3039 B to constrain the true age of the double pulsar system,the initial orbital period and initial binary separation are obtained as 2.89 h and 1.44 x 106 km,respectively,and the coalescence age or the lifetime from the birth to merger of PSR J0737-3039 is obtained to be 1.38×10^(8)yr.At the last minute of coalescence,corresponding to the gravitational wave frequency changing from 20 Hz to1180 Hz,we present the binary separation of PSR J0737-3039 to be from 442 km to 30 km,while the spin periods of PSR J0737-3039 A and PSR J0737-3039 B are 27.10 ms and 4.63 s,respectively.From the standard radio pulsar emission model,before the system merged,the primary NS could still be observed by a radio telescope,but the companion NS had crossed the death line in the pulsar magnetic-field versus period(B-P)diagram at which point it is usually considered to cease life as a pulsar.This is the first time that the whole life evolutionary simulation of the orbit and spin periods for a double NS system is presented,which provides useful information for observing a primary NS at the coalescence stage.展开更多
文摘Objective To describe the clinical characteristics of idiopathic ventricular fibrillation （IVF） with fragmented QRS complex （f-QRS） and J wave in resting electrocardiogram. Methods We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram （ECG）. All the case subjects were classified among three groups based on the electrocardiographic morphology： group I, both f-QRS and J wave were observed （n = 6）, group II, only J wave was observed （n = 9）, group III, neither f-QRS nor J wave was observed （n = 6）. Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation （VF）, and circumstance of VF were evaluated among the three groups. Results The incidence of index events （syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator （ICD） or pacemakers） was 13.4 ~ 5.6 per-year in group I, 10.8 ~ 3.9 per-year in group II, and 9.8 -4- 4.2 per-year in group HI. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 （95%CI, 1.1-7.9; P = 0.01）. The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. Conclusions This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.
基金supported in part by the JSPS-CAS Core University Program in the field of Plasma and Nuclear Fusion
文摘The possibility of driving poloidal flows by use of ion Bernstein wave is assessed for Heliotron J and EAST devices by means of ray tracing analysis. Sheared poloidal flow is expected to suppress plasma turbulences due to the decorrelation of the waves. In Heliotron J and EAST plasma, the rays of Ion Bernstein Wave travel into the central region with oscillations along the magnetic lines of force and their power is absorbed by ions at the cyclotron resonance layers. The momentum input has been estimated by calculating the momentum change of rays and the poloidal flow has been estimated using neoclassical viscosities. The wave momentum changes its sign as it propagates inward, depositing sheared momentum to the plasma, and therefore causes sheared poloidal flows.
基金grants from the National Nat-ural Science Foundation of China，the PhD Programs Foundation of Ministry of Education of China (20120001120131). The authors of this article do not have potential conflicts of interest
文摘Vasospastic angina is caused by sudden occlusive vasoconstriction of a segment of an epicardial artery, which can present with a wide spectrum of clinical scenario. We report the cases of two patients diagnosed with vasospastic angina, with one of which presenting with sudden cardiac arrest, while the other presenting with a relatively benign syncope. But both of them have J waves formation on ECG during active ischemia. The diagnosis and management of vasospastic angina, as well as the proposed clinical significance of J waves during coro- nary soasm are discussed.
基金supported by the National Natural Science Foundation of China(NSFC,Grant Nos.11988101,11773005,U1631236,11703001,U1731238,U1938117,11725313,11721303)the International Partnership Program of Chinese Academy of Sciences(Grant No.114A11KYSB20160008)+3 种基金the National Key R&D Program of China(No.2016YFA0400702)supported by the National Basic Research Program(973 Program)(No.2015CB857100)National Key R&D Program of China(No.2017YFA0402600)the Guizhou Provincial Science and Technology Foundation(Grant No.[2020]1Y019)。
文摘The complete orbital and spin period evolutions of the double neutron star(NS)system PSR J0737-3039 are simulated from birth to coalescence,which include the two observed radio pulsars classified as primary NS PSR J0737-3039 A and companion NS PSR J0737-3039 B.By employing the characteristic age of PSR J0737-3039 B to constrain the true age of the double pulsar system,the initial orbital period and initial binary separation are obtained as 2.89 h and 1.44 x 106 km,respectively,and the coalescence age or the lifetime from the birth to merger of PSR J0737-3039 is obtained to be 1.38×10^(8)yr.At the last minute of coalescence,corresponding to the gravitational wave frequency changing from 20 Hz to1180 Hz,we present the binary separation of PSR J0737-3039 to be from 442 km to 30 km,while the spin periods of PSR J0737-3039 A and PSR J0737-3039 B are 27.10 ms and 4.63 s,respectively.From the standard radio pulsar emission model,before the system merged,the primary NS could still be observed by a radio telescope,but the companion NS had crossed the death line in the pulsar magnetic-field versus period(B-P)diagram at which point it is usually considered to cease life as a pulsar.This is the first time that the whole life evolutionary simulation of the orbit and spin periods for a double NS system is presented,which provides useful information for observing a primary NS at the coalescence stage.
