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SAGE based iterative receiver for joint synchronization and channel estimation in uplink MIMO-OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 100-104页

作者： JIANG zheng QIN Xiao-fang zhang Xin CHANG Yong-yu Wireless Theories and Technologies Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

A new Turbo iterative receiver structure is proposed for the uplink multiple-input multiple-output orthogonal frequency division multiple access （MIMO-OFDMA） systems. The space-alternating generalized expectation-maximization （SAGE） algorithm is naturally embedded in the framework of iterative receiver to perform synchronization and detection usin~ the Turbo detector outputs. In each iteration, the expectation step intends to remove the multiple access interference （MAI） caused by other asynchronous users, and the maximization step is utilized to estimate the required parameters （i.e., timing offset, carrier frequency offset, channel state information, etc.） sequentially for each user. Simulation results show that the proposed algorithm can approach the performance of ideal receiver closely, while the processing complexity is rather lower than the conventional detectors.

关键词： SAGE iterative receiver synchronization channel estimation

A NEW MOLYBDENUM OXIDE PHASE

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Acta Metallurgica Sinica(English Letters) 1990年第11期3卷 308-311页

作者： fang zheng zhang Pingmin CHEN Xinmin Central-South University of Technology,Changsha,China fang zheng,Associate Professor,Dept.of Chemistry,Central South University of Technology,Changsha 410083,China

A new molybdenum oxide phase which exists in bomb combustion products of Mo was found. It has been determined that this phase is a transformed MoO_3 of triclinic *** set of its lattice parameters was also determined from the X-ray diffraction data as α=0.4049± 0.0001 nm,b=0.5079±0.0003 nm,c=1.4339±0.0009 nm,α=115.16±0.08°,β=90.69± 0.14°,γ=105.58±0.05° and unit cell volume=0.2544 nm^3.

关键词： Mo oxide bomb combustion MoO_3 transgorm

Outcomes of primary percutaneous coronary intervention for acute ST-elevation myocardial infarction in patients aged over 75 years

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Chinese Medical Journal 2006年第14期119卷 1151-1156页

作者： zhang Qi zhang Rui-yan zhang Jian-sheng HU Jian YANG Zhen-kun zheng Ai-fang zhang Xian SHEN Wei-feng Department of Cardiology Shanghai Ruijin Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200025 China

Background The optimal reperfusion strategy in elderly patients with ST-elevation myocardial infarction （STEMI） remains unclear. The purpose of this study was to evaluate the safety, in-hospital and one-year clinical outcomes for patients 〉75 years of age with STEMI receiving primary percutaneous coronary intervention （PCI）, compared with those treated by conservative approach. Methods One hundred and two patients 〉75 years of age with STEMI presented 〈12 hours were randomly allocated to primary PCI （n=50） or conservative therapy only （n=52）. The baseline characteristics, in-hospital outcome and major adverse cardiac events （MACE）, including death, non-fatal myocardial infarction and target vessel revascularization at one-year clinical follow-up were compared between the two groups. Results Age, gender distribution, risk factors for coronary artery disease, infarct site and clinical functional status were similar between the two groups, but the patients in primary PCI group received less low-molecular- weight heparin during hospitalization. Compared with conservative group, the patients in primary PCI group had significantly lower occurrence rate of re-infarction and death and shortened hospital stay. The composite endpoint for in-hospital survivals at 30-day follow-up was similar between the two groups, but one-year MACE rate was significantly lower in the primary PCI group （21.3% and 45.2%, P=0.029）. Left ventricular ejection fraction was not significantly changed in both groups during follow-up. Multivariate analysis revealed that primary PCI （OR=0.34, 95% CI： 0.21-0.69, P =0.03） improved MACE-free survival rate for STEMI patients aged 〉 75 years. Conclusion Our results indicated that primary PCI was safe and effective in reducing in-hospital mortality and one-year MACE rate for elderly patients with STEMI.

关键词： myocardial infarction elderly angioplasty outcome

Short-term effect of cardiac resynchronization therapy in patients with ischaemic or nonischaemic cardiomyopathy

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Chinese Medical Journal 2006年第18期119卷 1507-1510页

作者： HUA Wei NIU Hong-xia WANG fang-zheng zhang Shu CHEN Ke-ping CHEN Xin Department of Clinical Electrophysiology Fuwai Hospital and Cardiovascular Institute Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100037 China

Background Patients with heart failure were candidates for cardiac resynchronization therapy （CRT） regardless of underlying aetiology. This study observed the effect of CRT in patients with ischaemic or nonischaemic cardiomyopathy. Methods One hundred and forty-two patients with refractory chronic heart failure and left bundle branch block received cardiac resynchronization therapy, 91 men and 51 women, average age 60 years. Left ventricular ejection fraction （LVEF） was severely depressed （mean 29%）, left ventricular end diastolic diameter （LVEDD） enlarged （mean 72 mm） and QRS width was lengthened （mean 147 ms）. Ninety-eight had nonischaemic cardiomyopathy and 44 had ischaemic cardiomyopathy. Results After cardiac resynchronization therapy, the heart function was significantly improved. The mean LVEF increased from 29% to 36% after pacing. In patients with nonischaemic cardiomyopathy, the LVEF was improved from 28% to 37%, and in patients with ischaemic cardiomyopathy, the LVEF was improved from 30% to 36%. No significant difference of the improvement was found between the two groups （P〉0.05）. Conclusions Cardiac resynchronization therapy could significantly improve cardiac function in patients with chronic heart failure regardless of the underlying heart disease.

关键词： cardiac resynchronization therapy cardiomyopathy, ischaemic nonischaemic

Potential predictors of non-response and super-response to cardiac resynchronization therapy

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Chinese Medical Journal 2011年第9期124卷 1338-1341页

作者： QIAO Qing DING Li-gang HUA Wei CHEN Ke-ping WANG fang-zheng zhang Shu Centre of Arrhythmia Diagnosis and Treatment Fuwai HospitalChinese Academy of Medical Sciences Peking Union Medical College Beijing 100037 China

Background Although cardiac resynchronization therapy （CRT） is already an established treatment, the characteristics of patients who have an excellent response to CRT and those who get no benefit remain to be determined. The purpose of this study was to search for potential predictors of both non-response and super-response to *** Seventy-six consecutive patients who received CRT treatment were divided into group A （non-responders）,group C （super-responders） and group B （responders exclusive of super-responders）. Student＇s t test, Mann-Whitney test, Logistic regression and receiver operating characteristic curve were employed to identify potential predictors among the patients＇ demographic characteristics, clinical features, several electrocardiographic parameters before and after CRT implantation, and their pre-implant echocardiographic *** Group A had the lowest 3-month left ventricular ejection fraction （LVEF）. Group C had the smallest pre-implant left ventricular end-diastolic dimension （LVEDD）, the shortest post-implant QRS duration, the smallest 3-month LVEDD and the highest 3-month LVEF. In addition, there was a trend of gradual change in percent of left bundle branch block,severity of pre-implant mitral regurgitation, pre-implant QRS dispersion, post-implant QRS duration as well as post-implant QRS dispersion from group A to group B and from group B to group C. Multivariable Logistic analysis revealed that only pre-implant LVEDD could predict CRT super-response. A pre-implant LVEDD of 68.5 mm was the cut-off value that identified super-responders with 87.5% sensitivity and 79.7% specificity. A pre-implant LVEDD of 62.5mm identified super-responders with 50.0% sensitivity and 89.8% *** Predictors of a CRT non-response remain unclear at present. But it is credible that patients with a smaller left ventricle would have a better chance to become super-responders to CRT.

关键词： cardiac resynchronization therapy non-response super-response predictor

Complications of cardiac resynchronization therapy in patients with congestive heart failure

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Chinese Medical Journal 2006年第6期119卷 449-453页

作者： NIU Hong-xia HUA Wei WANG fang-zheng zhang Shu CHEN Ke-ping CHEN Xin Centre of Arrhythmia Diagnosis and Treatment Fuwai HospitalChinese Academy of Medical Sciences and Peking Union MedicalCollege Beijing 100037 China

Background Previous clinical studies have suggested that patients with congestive heart failure and intraventricular conduction delay could benefit from cardiac resynchronization therapy （CRT）. Implantation of left ventricular lead is a complex procedure with some potential for complications. This study was conducted to analyse the complications of CRT in patients with congestive heart failure.Methods Totally 117 patients, 86 males and 31 females, mean age of 53 years, with congestive heart failure and intraventricular conduction delaywere enrolled in this study. Venography was performed on all patients. Different types of coronary sinus leads were used to pace the left ventricle.Results Left ventricular lead was attempted to implant through coronary sinus for all the 117 patients and was successfully implanted in 111 patients. The success rate was 94.9%. Main complications rate was 6.8%, including coronary sinus dissection in 4 patients, phrenic nerve stimulation required lead repositioning in 2 patients and lead dislodgement in 2 patients.Conclusions It is feasible and safe to pace left ventricle through coronary sinus. However, there are some procedural complications.

关键词： cardiac resynchronization therapy congestive heart failure compfication

BASIC　EQUATIONS　FOR　THERMO－ELECTROCHEMISTRYAND　THE　ENTROPY　CHANGE　OF　THE　STANDARDHYDROGEN　ELECTRODE　REACTION

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Acta Metallurgica Sinica(English Letters) 1996年第3期9卷 189-192页

作者： fang zheng, zhang Hengzhong, zhang Pingming, HUANG Shengtang,GUO Li and HU Guoqiang(Department of Chemistry, Central South University of Technology, Changsha 410O83, China)

A set of thermo-electrochemical (TEC) equations for the cell and half-cell reactions has been derived. Is is shown that the difference between the enthalpy change determined by TEC technology and the one calculated with the current thermodynamic data of ions of any half-cell reaction in electochemical systems is coastant. The absolute entrupy change of the standard hydrogen electrode reaction was determined to be 85.2 J.K-1 .mol-1 at room temperature:

关键词： thermo-electrochemistry absolute entropy standard hydrogen electrode

Single center experience with intrathoracic impedance monitoring in chronic heart failure patients

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Chinese Medical Journal 2011年第14期124卷 2219-2221页

作者： QIAO Qing HUA Wei DING Li-gang CHEN Ke-ping WANG Jing WANG fang-zheng zhang Shu Centre of Arrhythirtia Diagnosis and Treatment Fuwai Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100037 China

Background The Medtronic InSync Sentry is the first available cardiac resynchronization therapy defibrillator （CRT-D）which can monitor fluid status by measuring intrathoracic impedance. This study was designed to observe the effectiveness of intrathoracic impedance monitoring on detecting aggravation of heart *** We retrospectively analyzed the clinical data of 14 consecutive patients. Patients were regularly followed up every 3-6 months after the implantation. At each visit, interrogation of the device was done. Patients were instructed to inform the researcher on hearing the device alert, and to take extra 40 milligrams of furosemidum if they had aggravated symptoms later. If the symptoms could not be relieved, they were asked to see a doctor. Data about heart failure hospitalization were collected from the medical *** During 18-48 months follow-up, a total of 7 patients encountered 28 alert events. On one hand, alert events appeared before all deteriorated symptoms and heart failure hospitalizations. On the other hand, there were 23 alerts followed by deterioration of heart failure symptoms, and 2 alerts related to 2 hospitalizations caused by pulmonary infection in one patient. Only 5 patients were hospitalized 10 times for deterioration of cardiac *** The function of intrathoracic impedance monitoring is reliable in predicting deterioration of heart failure.

关键词： heart failure intrathoracic impedance cardiac resynchronization therapy defibrillator

Mechanisms of Difference in Mn Efficiency Between Wheat and Oilseed Rape

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Pedosphere 2000年第3期10卷 213-220页

作者： fangzheng zhangFUSUO MountainousDistrictInstituteofHebeiAgriculturalUniversity Baoding071001China DepartmentofPlantNutrition ChinaAgriculturalUniversityBeijing100094China

By solution culture experiment, three wheat genotypes (Ttiticum aestivum L.) and two oilseed rape genotypes (Brassica napus L.) differing in Mn efficiency under Mn-deficient conditions were used to study mechanisms of the difference in Mn efficiency between wheat and oilseed rape. The results showed that there were significant differences in the abilities of MnIV reduction and acidification in root rhizosphere between the two species. Compared with wheat, oilseed rape had much higher reducing capacity and intensity of rhizosphere acidification under Mn-deficient conditions. Moreover, the higher ratio of functional leaves Mn/old leaves Mn in oilseed rape than in wheat was also an important factor for the different Mn efficiencies between the two species.

关键词： genotypic difference mechanism Mn efficiency oilseed rape whL