Electronic processes within atoms and molecules reside on the timescale of attoseconds. Recent advances in the laserbased pump-probe interrogation techniques have made possible the temporal resolution of ultrafast ele...Electronic processes within atoms and molecules reside on the timescale of attoseconds. Recent advances in the laserbased pump-probe interrogation techniques have made possible the temporal resolution of ultrafast electronic processes on the attosecond timescale, including photoionization and tunneling ionization. These interrogation techniques include the attosecond streak camera, the reconstruction of attosecond beating by interference of two-photon transitions, and the attoclock. While the former two are usually employed to study photoionization processes, the latter is typically used to investigate tunneling ionization. In this review, we briefly overview these timing techniques towards an attosecond temporal resolution of ionization processes in atoms and molecules under intense laser fields. In particular, we review the backpropagation method, which is a novel hybrid quantum-classical approach towards the full characterization of tunneling ionization dynamics. Continued advances in the interrogation techniques promise to pave the pathway towards the exploration of ever faster dynamical processes on an ever shorter timescale.展开更多
BACKGROUND: Although the use of non-heart beating donors (NHBDs) could bridge the widening gap between organ demand and supply, its application to liver transplantation is limited due to the high incidence of primary ...BACKGROUND: Although the use of non-heart beating donors (NHBDs) could bridge the widening gap between organ demand and supply, its application to liver transplantation is limited due to the high incidence of primary graft loss. Prevention of liver injury in NHBDs will benefit the results of transplantation. This study was conducted to evaluate the protective effects of L-arginine on liver grafts from NHBDs. METHODS: One hundred and four Wistar rats were randomly divided into 7 groups: normal control (n=8) controls 1, 2 and 3 (C-1, C-2, C-3, n=16), and experimental 1, 2 and 3 (E-1, E-2, E-3, n=16). For groups C-1 and E-1, C-2 and E-2, and C-3 and E-3, the warm ischemia time was 0, 30, and 45 minutes, respectively. Liver grafts were flushed with and preserved in 4 degrees C Euro-collins solution containing 1 mmol/L L-arginine for 1 hour in each experimental group. Recipients of each experimental group were injected with L-arginine (10 mg/kg body weight) by tail vein 10 minutes before portal vein reperfusion. Donors and recipients of each experimental control group were treated with normal saline. Then transplantation was performed. At 1, 3, and 24 hours after portal vein reperfusion, blood samples were obtained to determine the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide (NO) and plasma endothelin (ET). At 3 hours after portal vein reperfusion, grafts samples were fixed in 2.5% glutaraldehyde for electron microscopic observation. RESULTS: At I hour after portal vein reperfusion, the levels of NO in groups E-1, E-2, E-3 and C-1, C-2, C-3 were lower, while the levels of plasma ET, serum ALT and AST were higher than those in the normal control group (P<0.05). At 1, 3, and 24 hours, the levels of NO in groups E-1, E-2, E-3 were higher, while the levels of plasma ET, serum ALT and AST were lower than those in the corresponding control groups (C-1, C-2, C-3) (P<0.05). The levels of NO in groups C-2 and C-3 were lower than in group C-1 (P<0.05), and the level of NO in group C-3 was lower than in group C-2 (P<0.05). At 1, 3 and 24 hours, the levels of plasma ET, serum ALT, and AST in groups E-1, E-2, E-3 were lower than those in the corresponding control groups (C-1, C-2, C-3) (P<0.05). The levels of plasma ET, serum ALT, and AST were lower in group C-3 than in groups C-1 and C-2 (P<0.05). Pathological changes in groups E-1, E-2, E-3 were milder than those in the corresponding experimental control groups (C-1, C-2, C-3). CONCLUSIONS: The imbalance between NO and ET plays an important role in the development of ischemia-reperfusion injury of liver grafts from NHBDs. L-arginine can attenuate injury in liver grafts from NHBDs by improving the balance between NO and ET.展开更多
The present research of cold-beating formation mainly focused on roller design and manufacture, kinematics, constitutive relation, metal flow law, thermo-mechanical coupling, surface micro-topography and microstructur...The present research of cold-beating formation mainly focused on roller design and manufacture, kinematics, constitutive relation, metal flow law, thermo-mechanical coupling, surface micro-topography and microstructure evolution. However, the research on surface quality and performance of workpieces in the process of cold-beating is rare. Cold-beating simulation experiment of 1020 steel is conducted at room temperature and strain rates ranging from 2000 to 4000 s^-1 base on the law of plastic forming. According to the experimental data, the model of strain hardening of 1020 steel is established, Scanning Electron Microscopy(SEM) is conducted, the mechanism of the work hardening of 1020 steel is clarified by analyzing microstructure variation of 1020 steel. It is found that the strain rate hardening effect of 1020 steel is stronger than the softening effect induced by increasing temperatures, the process of simulation cold-beating cause the grain shape of 1020 steel significant change and microstructure elongate significantly to form a fibrous tis- sue parallel to the direction of deformation, the higher strain rate, the more obvious grain refinement and the more hardening effect. Additionally, the change law of the work hardening rate is investigated, the relationship between dislocation density and strain, the relationship between work hardening rate and dislocation density is obtained. Results show that the change trend of the work hardening rate of 1020 steel is divided into two stages, the work hardening rate decreases dramatically in the first stage and slowly decreases in the second stage, finally tending toward zero. Dislocation density increases with increasing strain and strain rate, work hardening rate decreases with increasing dislocation density. The research results provide the basis for solving the problem of improving the surface quality and performance of workpieces under cold-beating formation of 1020 steel.展开更多
Diagnostic techniques of CEOF, power spectrum and bandpass filter wave are applied in this paper to analyze the seasonal northward beating of the northern subtropical high using day to day geopotential fields of 2.5 &...Diagnostic techniques of CEOF, power spectrum and bandpass filter wave are applied in this paper to analyze the seasonal northward beating of the northern subtropical high using day to day geopotential fields of 2.5 ×2.5 at 500 hPa May through July in 1988 and 1991. It is concluded that it is globally observed that the subtropical high has northward beats that propagate westward; the source of beating mainly lies in the region of Arabian Sea and central Pacific and the sink in eastern Pacific; the seasonal beating is dominated by effects of the disturbance field; low frequency oscillation plays a key role in the beating and the westward propagation so that the difference in the latter in individual years is caused by the varying source of disturbance and the low frequency waves it excites.展开更多
In this paper,what causes the setting-on place of woven fabrics without adopting tension compensation is explained by means of experimental methods.Owing to that the main shaft speed and the beating speed of reed can ...In this paper,what causes the setting-on place of woven fabrics without adopting tension compensation is explained by means of experimental methods.Owing to that the main shaft speed and the beating speed of reed can not attain the normal values at setting-on,the warp tension and the beating force of the reed can neither reach the normal level.Therefore,the relative slippage movement of the weft against the warp during beating will be less,while the common movement of the weft together with the warp will be bigger than those at nor-mal running.As a result,the setting-on place is展开更多
In this paper, the intrinsic behavior of rotating Euler Benoulli flexible shafts was studied due to coupled bending and torsional vibrations. The equations of motion of the shaft with unbalanced eccentricity and visc...In this paper, the intrinsic behavior of rotating Euler Benoulli flexible shafts was studied due to coupled bending and torsional vibrations. The equations of motion of the shaft with unbalanced eccentricity and viscous material damping were derived by the Hamilton principle. The numerical solution was obtained using the perturbation approach and mode assuming method. The influences of the coupled vibrations between the bending and torsion, the rotating speed, material damping and the slenderness ratio of the shaft were analyzed. It is clearly shown that the beating phenomena can occur when the interaction of torsion and flexure is considered.展开更多
Objective: To study the outcome of normothermic beating heart pulmonary thromboendarterectomy (PTE) performed in patients with chronic pulmonary thromboembolism. Methodology: A retrospective analysis of 15 patients wh...Objective: To study the outcome of normothermic beating heart pulmonary thromboendarterectomy (PTE) performed in patients with chronic pulmonary thromboembolism. Methodology: A retrospective analysis of 15 patients who underwent PTE under normothermic beating heart cardio-pulmonary bypass from July 2009 to September 2018 was done. The patients were followed up with clinical assessment, transthoracic echocardiography and computerized tomographicangiography (CTA) for 1 month to 82 months. Results: Data were analysed for 15 consecutive patients. Mean age of the patients was 35.28 years and 10 patients were male. Pre-operatively 6 (40%) patients presented with New York Heart Association (NYHA) class II dyspnoea on exertion symptomatology, 7 (47%) were in NHYA class III, and 2 (13%) were in NYHA class IV. The preoperative and postoperative mean pulmonary artery pressures (mPAP) (mmHg) were 36.50 ± 11.3 and 20.21 ± 7.19, the systolic PAPs (mmHg) were 73.35 ± 14.12 and 35.21 ± 7.89 and the diastolic PAPs (mmHg) were 19.28 ± 8.60 and 12.85 ± 7.26 respectively. 2 (13%) patients had Jamieson’s type I and 12 (87%) had Jamieson type II disease. One patient (7%) expired on 9th postoperative day. All the patients had improved pulmonary gas exchange and did not require oxygen supplementation from 5th postoperative day;symptoms improved to NYHA class I & II in 12 (80%) & 3 (20%) of patients respectively. There was no reperfusion pulmonary edema or any neurologic complications. Postoperative echocardiogram showed improved right ventricular function and Computerised Tomographic Angiogram showed completeness of the procedure. Conclusion: Pulmonary thromboendarterectomy under normothermic beating heart cardiopulmonary bypass has good immediate postoperative results with significant progressive improvement in hemodynamics and quality of life during the course of follow-up. The results were not only comparable to those of the procedure done under deep hypothermic circulatory arrest by other centres but also without its associated adverse events. This technique requires more expertise but gives equivalent good results in immediate and short- to mid-term follow-up with less morbidity than the standard procedure, but it requires long-term follow-up to substantiate the evidence.展开更多
ZTE Corporation appeared at Expo Comm China2004 with a range of world-leading solutions andapplications stretching across the entiretechnology spectrum-from mobile and NGNrequirements to videoconferencing and
With the experience of over 250 beating hear operations since Feb 1995 westarted minimally invasive revascularization of the LAD(MIDCAB).SinceFeb.1996 we operated upon 182 patients with this procedure Since June1996 w...With the experience of over 250 beating hear operations since Feb 1995 westarted minimally invasive revascularization of the LAD(MIDCAB).SinceFeb.1996 we operated upon 182 patients with this procedure Since June1996 we treated 40 patients with multivessel discase with a Hybridproccdurc(PTCA plus MIDCAB)The age of the patients ranged between 68 and 79 years.29 patients waremaic.28 patiens suffered from a double vessel discase.12 patients fromtriple vessel discase.The left ventricular ejeetion fraction was loss then 40%in 8 cases 2 patients underwent a reoperativc procedure.Further risk factorswere COLD(n=9).recent MI(n=6),renal insufliciency(n=13).Diabeiesinellitus(n-12).The left mammary was prepared in the usual manner.As access wechese a partial inferior sternotomy(n=4)or a lateral minithoracotomy(n=36).The anastomosis was performed on the beating heart.In all patients we conneeted the LIMA to the LAD.All patients survived andcould be discharged on the 6th postoperative day(mean).In two patients arevision due to bleeding became necessary.Two patients reccived a bloodtransfusions.Postoperatively 15 patients reccived a PTCA of the RCX.4 astentimplantation to the Rex.16 a PTCA of the RCA.5 a stentimplantationto the RCA and 3 patients a PTCA of a D1.3 patients developed a falscaneurysm after the cathcter intervention.By performing the nunimally invasive proeedure the trauma caused bycxtracorporeal circulation can be avoided.Through the combination withPTCA a less invasive therapy of coronary multivessel discase becomespossible in select patients.Postoperative complications and hospital stay canbe teduced.展开更多
Objective: Acute kidney disease develops 16% - 30% of patients with preoperative impaired renal functions. Our aim of this study was to compare postoperative renal outcomes using two open heart surgery techniques, on-...Objective: Acute kidney disease develops 16% - 30% of patients with preoperative impaired renal functions. Our aim of this study was to compare postoperative renal outcomes using two open heart surgery techniques, on-pump beating heart (OPBH) and conventional on-pump (COP), in patients who have preoperative low glomerular filtration rate (eGFR) as an indicator of creatinine clearance. Methods: From 2004 to 2015, 341 patients with preoperative creatinine clearance were lower than 90 ml/min/1.73m2 were selected for this study. On-Pump beating heart was performed in 111 patients (Group I). Conventional on-pump technique was used in 200 patients. In the remaining patients, we measured postoperative Tumor Necrosis Factor Alpha (TNF-alpha), cardiac troponin I (cTn-I), Brain natriuretic peptid (NT-Pro- BNP), creati-nine (Cr), blood urea nitrogen (BUN) and postoperative eGFR daily until day four after surgery. Results: There were no differences in baseline levels of TNF-alpha, NT-Pro-BNP, BUN, cTn-I, Cr levels between the groups. Cardiopulmonary bypass (CPB) time were much longer and cumulative inotrope use was significantly higher in patients underwent COP (P Conclusion: Our study showed that on-pump beating heart CABG technique provides a morbidity benefit and is associated with a lower risk of peroperative LOS in patients with mild renal disfunction. Our study results suggest that OPBH is superior to the COP in terms of postoperative renal injury and cardiac mediators.展开更多
More than any other time of the year,everyone is shopping and nobody wants to overpay because they missed out on a coupon or promo code.Customers have found the easiest way to save is by downloading a smartphone app.B...More than any other time of the year,everyone is shopping and nobody wants to overpay because they missed out on a coupon or promo code.Customers have found the easiest way to save is by downloading a smartphone app.But after the transaction is completed...they hit the delete button.This dance doesn’t play out only during the holidays,though.Savvy consumers do this all year long-leaving brands and retailers to wonder how展开更多
Background Off-pump coronary artery bypass grafting (CABG) is becoming increasingly popular world - wide. But it is not always feasible. Current cardioplegic techniques do not consistently avoid myocardial ischemic da...Background Off-pump coronary artery bypass grafting (CABG) is becoming increasingly popular world - wide. But it is not always feasible. Current cardioplegic techniques do not consistently avoid myocardial ischemic damage. So we use on pump beating heart technique to supplement off-pump CABG. Methods Based on 860 off-pump CABG cases between Aug 1998 to Aug 2000. From Aug 1999 to Aug 2000, 46 CABG cases were performed with on pump beating heart technique at Mani-pal Hospital Heart Foundation, Bangalore, India. All surgeries were performed through a median sternotomy. Exposure techniques were tailored to individual vessels and cardiac regions and local immobilization was performed with octopus. Vascular control was achieved with occluders and shunts. Total cardiopulmonary bypass (CPB) was established before or during CABG and normolthemia was used. Results Among 46 on -pump beating heart CABG patients, 26 patients used CPB before or during OP - CABG because of unstable hemodynamics and electric instability , 7 had very deep intramyocardial left anterior descending arteries, 5 patients had poor LV function (LVEF < 30 % ), 8 patients had cardiomegaly. The average number of grafts was 3.5. No operative mortality. Three patients had postoperative myocardial infarction. Anesthetic time 4. 5±1. 2 hours, extubation time 10±2. 5 hours, blood lost 680±230 mL, blood requirement 540±150 mL, preoperative LVEF 50. 3±13 % , postoperative LVEF 64. 1±14 %, ICU stay 1. 5±0. 5 days, hospi- tal stay 9.2±1.8 days. Conclusion Complete coronary revascularization with on pump beating heart is a supplement for off - pump CABG when it is not feasible. It eliminates intraoperative globe myocardial ischemia and avoids transient myocardial injury during cardioplegic arrest and myocardial reperfusion.展开更多
Background Cardiopulmonary bypass (CPB) produces a well documented diffuse inflammatory response that affects multiple organ systems. To avoid the deleterious effects of cardiopulmonary bypass, off pump coronary art...Background Cardiopulmonary bypass (CPB) produces a well documented diffuse inflammatory response that affects multiple organ systems. To avoid the deleterious effects of cardiopulmonary bypass, off pump coronary artery bypass grafting is becoming increasingly popular world wide. We reviewed our experience of complete coronary artery revascularization on the beating heart without CPB. Methods From Aug 1998 to Aug 2000, 860 off pump revascularizations (99%since January 1999) were performed at Manipal Hospital Heart Foundation. The patients consist of males 757(88%), females 103(12%). Averaged age 64.2±15 years. All surgeries were performed through a median sternotomy. Exposure techniques are tailored to individual vessels and cardiac regions. Local immobilization is performed with octopus. Vascular control is achieved with occluders and shunts. Results Among 860 off pump CABG patients. Single graft 72 (8.3%), two grafts 208 (24.2%), three grafts 469 (54.5%), four grafts 101 (11.8%), five graft 10 (1.2%). The average number of grafts per patient was 2.72±0.32. Operative mortality was 0.69%(6 patients). Anesthetic time 3.9±1.2hours, extubation time 6±2.5 hours, Blood requirement 360±90 ml, Preoperative LVEF 60.2±8.5%, Post LVEF 64.1±14%Low cardiac output 48 patients (5.6%), IABP requirement: 25 patients(2.9%), 25 patients converted to CPB during OP CAB(2.9%)and 20 of them were done with on pump beating heart. 25 patients showed myocardial ischemic and 16 patients showed perioperative myocardial infarction. ICU stay 1.1±0.8 days, hospital stay 6.2±1.1 days. Conclusion Off-pump coronary artery bypass in complete revascularization is a safe, effective technique and suitable.展开更多
Vienna Symphony Orchestra Concert Vienna Symphony Orchestra Date:May 29-31,2023 Venue:National Center for the Performing Arts With a rich history steeped in tradition,the courage to stand apart and an enduring joy of ...Vienna Symphony Orchestra Concert Vienna Symphony Orchestra Date:May 29-31,2023 Venue:National Center for the Performing Arts With a rich history steeped in tradition,the courage to stand apart and an enduring joy of discovery,the Vienna Symphony Orchestra is the beating heart of Vienna—the metropolis of classical music.For 120 years,the orchestra shaped the special sound of its native city,forging a link between past,present,and future like no other.展开更多
上世纪90年代后期以来,“在路上”成为中国文学界的流行话语,它源于“垮掉的一代”(BG)作家凯鲁亚克的小说《在路上》(On the Road),其起源语境、语义与BG相关。小说中BG伙伴横穿美国,在路上酗酒、吸毒、滥交,反抗美国现存体制,体验主...上世纪90年代后期以来,“在路上”成为中国文学界的流行话语,它源于“垮掉的一代”(BG)作家凯鲁亚克的小说《在路上》(On the Road),其起源语境、语义与BG相关。小说中BG伙伴横穿美国,在路上酗酒、吸毒、滥交,反抗美国现存体制,体验主流文化之外另一种生活。他们为一种莫名的想望不知疲倦地奔走,在疯狂中感觉自我,所以“在路上”语义非常复杂。中国移植者将它从其起源语境中剥离出来,抽空其原义,对其作望文生义的理解,使其抽象化、普泛化,弱化了它对于中国文化建构的价值与意义。展开更多
This paper studies post-war America around the 1950's when On the Road was written and analyzes the protagonist Dean Moriarty as a spokesman of the Beat Generation.He is a typical beat who revolts against the trad...This paper studies post-war America around the 1950's when On the Road was written and analyzes the protagonist Dean Moriarty as a spokesman of the Beat Generation.He is a typical beat who revolts against the traditional social values and chases after the spiritual complacency.In addition,he opposes wars and advocates the equality between men and women.Thus in a sense Dean is a rebellious hero and stands ahead of his age.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.92150105,11834004,12227807,and 12241407)the Science and Technology Commission of Shanghai Municipality (Grant No.21ZR1420100)。
文摘Electronic processes within atoms and molecules reside on the timescale of attoseconds. Recent advances in the laserbased pump-probe interrogation techniques have made possible the temporal resolution of ultrafast electronic processes on the attosecond timescale, including photoionization and tunneling ionization. These interrogation techniques include the attosecond streak camera, the reconstruction of attosecond beating by interference of two-photon transitions, and the attoclock. While the former two are usually employed to study photoionization processes, the latter is typically used to investigate tunneling ionization. In this review, we briefly overview these timing techniques towards an attosecond temporal resolution of ionization processes in atoms and molecules under intense laser fields. In particular, we review the backpropagation method, which is a novel hybrid quantum-classical approach towards the full characterization of tunneling ionization dynamics. Continued advances in the interrogation techniques promise to pave the pathway towards the exploration of ever faster dynamical processes on an ever shorter timescale.
基金a grant from the Science & Technology Development Foundation of Guangdong Health Bureau(No.2006345).
文摘BACKGROUND: Although the use of non-heart beating donors (NHBDs) could bridge the widening gap between organ demand and supply, its application to liver transplantation is limited due to the high incidence of primary graft loss. Prevention of liver injury in NHBDs will benefit the results of transplantation. This study was conducted to evaluate the protective effects of L-arginine on liver grafts from NHBDs. METHODS: One hundred and four Wistar rats were randomly divided into 7 groups: normal control (n=8) controls 1, 2 and 3 (C-1, C-2, C-3, n=16), and experimental 1, 2 and 3 (E-1, E-2, E-3, n=16). For groups C-1 and E-1, C-2 and E-2, and C-3 and E-3, the warm ischemia time was 0, 30, and 45 minutes, respectively. Liver grafts were flushed with and preserved in 4 degrees C Euro-collins solution containing 1 mmol/L L-arginine for 1 hour in each experimental group. Recipients of each experimental group were injected with L-arginine (10 mg/kg body weight) by tail vein 10 minutes before portal vein reperfusion. Donors and recipients of each experimental control group were treated with normal saline. Then transplantation was performed. At 1, 3, and 24 hours after portal vein reperfusion, blood samples were obtained to determine the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), nitric oxide (NO) and plasma endothelin (ET). At 3 hours after portal vein reperfusion, grafts samples were fixed in 2.5% glutaraldehyde for electron microscopic observation. RESULTS: At I hour after portal vein reperfusion, the levels of NO in groups E-1, E-2, E-3 and C-1, C-2, C-3 were lower, while the levels of plasma ET, serum ALT and AST were higher than those in the normal control group (P<0.05). At 1, 3, and 24 hours, the levels of NO in groups E-1, E-2, E-3 were higher, while the levels of plasma ET, serum ALT and AST were lower than those in the corresponding control groups (C-1, C-2, C-3) (P<0.05). The levels of NO in groups C-2 and C-3 were lower than in group C-1 (P<0.05), and the level of NO in group C-3 was lower than in group C-2 (P<0.05). At 1, 3 and 24 hours, the levels of plasma ET, serum ALT, and AST in groups E-1, E-2, E-3 were lower than those in the corresponding control groups (C-1, C-2, C-3) (P<0.05). The levels of plasma ET, serum ALT, and AST were lower in group C-3 than in groups C-1 and C-2 (P<0.05). Pathological changes in groups E-1, E-2, E-3 were milder than those in the corresponding experimental control groups (C-1, C-2, C-3). CONCLUSIONS: The imbalance between NO and ET plays an important role in the development of ischemia-reperfusion injury of liver grafts from NHBDs. L-arginine can attenuate injury in liver grafts from NHBDs by improving the balance between NO and ET.
基金Supported by National Natural Science Foundation of China(Grant Nos.551475146,51475366,51075124)
文摘The present research of cold-beating formation mainly focused on roller design and manufacture, kinematics, constitutive relation, metal flow law, thermo-mechanical coupling, surface micro-topography and microstructure evolution. However, the research on surface quality and performance of workpieces in the process of cold-beating is rare. Cold-beating simulation experiment of 1020 steel is conducted at room temperature and strain rates ranging from 2000 to 4000 s^-1 base on the law of plastic forming. According to the experimental data, the model of strain hardening of 1020 steel is established, Scanning Electron Microscopy(SEM) is conducted, the mechanism of the work hardening of 1020 steel is clarified by analyzing microstructure variation of 1020 steel. It is found that the strain rate hardening effect of 1020 steel is stronger than the softening effect induced by increasing temperatures, the process of simulation cold-beating cause the grain shape of 1020 steel significant change and microstructure elongate significantly to form a fibrous tis- sue parallel to the direction of deformation, the higher strain rate, the more obvious grain refinement and the more hardening effect. Additionally, the change law of the work hardening rate is investigated, the relationship between dislocation density and strain, the relationship between work hardening rate and dislocation density is obtained. Results show that the change trend of the work hardening rate of 1020 steel is divided into two stages, the work hardening rate decreases dramatically in the first stage and slowly decreases in the second stage, finally tending toward zero. Dislocation density increases with increasing strain and strain rate, work hardening rate decreases with increasing dislocation density. The research results provide the basis for solving the problem of improving the surface quality and performance of workpieces under cold-beating formation of 1020 steel.
文摘Diagnostic techniques of CEOF, power spectrum and bandpass filter wave are applied in this paper to analyze the seasonal northward beating of the northern subtropical high using day to day geopotential fields of 2.5 ×2.5 at 500 hPa May through July in 1988 and 1991. It is concluded that it is globally observed that the subtropical high has northward beats that propagate westward; the source of beating mainly lies in the region of Arabian Sea and central Pacific and the sink in eastern Pacific; the seasonal beating is dominated by effects of the disturbance field; low frequency oscillation plays a key role in the beating and the westward propagation so that the difference in the latter in individual years is caused by the varying source of disturbance and the low frequency waves it excites.
文摘In this paper,what causes the setting-on place of woven fabrics without adopting tension compensation is explained by means of experimental methods.Owing to that the main shaft speed and the beating speed of reed can not attain the normal values at setting-on,the warp tension and the beating force of the reed can neither reach the normal level.Therefore,the relative slippage movement of the weft against the warp during beating will be less,while the common movement of the weft together with the warp will be bigger than those at nor-mal running.As a result,the setting-on place is
文摘In this paper, the intrinsic behavior of rotating Euler Benoulli flexible shafts was studied due to coupled bending and torsional vibrations. The equations of motion of the shaft with unbalanced eccentricity and viscous material damping were derived by the Hamilton principle. The numerical solution was obtained using the perturbation approach and mode assuming method. The influences of the coupled vibrations between the bending and torsion, the rotating speed, material damping and the slenderness ratio of the shaft were analyzed. It is clearly shown that the beating phenomena can occur when the interaction of torsion and flexure is considered.
文摘Objective: To study the outcome of normothermic beating heart pulmonary thromboendarterectomy (PTE) performed in patients with chronic pulmonary thromboembolism. Methodology: A retrospective analysis of 15 patients who underwent PTE under normothermic beating heart cardio-pulmonary bypass from July 2009 to September 2018 was done. The patients were followed up with clinical assessment, transthoracic echocardiography and computerized tomographicangiography (CTA) for 1 month to 82 months. Results: Data were analysed for 15 consecutive patients. Mean age of the patients was 35.28 years and 10 patients were male. Pre-operatively 6 (40%) patients presented with New York Heart Association (NYHA) class II dyspnoea on exertion symptomatology, 7 (47%) were in NHYA class III, and 2 (13%) were in NYHA class IV. The preoperative and postoperative mean pulmonary artery pressures (mPAP) (mmHg) were 36.50 ± 11.3 and 20.21 ± 7.19, the systolic PAPs (mmHg) were 73.35 ± 14.12 and 35.21 ± 7.89 and the diastolic PAPs (mmHg) were 19.28 ± 8.60 and 12.85 ± 7.26 respectively. 2 (13%) patients had Jamieson’s type I and 12 (87%) had Jamieson type II disease. One patient (7%) expired on 9th postoperative day. All the patients had improved pulmonary gas exchange and did not require oxygen supplementation from 5th postoperative day;symptoms improved to NYHA class I & II in 12 (80%) & 3 (20%) of patients respectively. There was no reperfusion pulmonary edema or any neurologic complications. Postoperative echocardiogram showed improved right ventricular function and Computerised Tomographic Angiogram showed completeness of the procedure. Conclusion: Pulmonary thromboendarterectomy under normothermic beating heart cardiopulmonary bypass has good immediate postoperative results with significant progressive improvement in hemodynamics and quality of life during the course of follow-up. The results were not only comparable to those of the procedure done under deep hypothermic circulatory arrest by other centres but also without its associated adverse events. This technique requires more expertise but gives equivalent good results in immediate and short- to mid-term follow-up with less morbidity than the standard procedure, but it requires long-term follow-up to substantiate the evidence.
文摘ZTE Corporation appeared at Expo Comm China2004 with a range of world-leading solutions andapplications stretching across the entiretechnology spectrum-from mobile and NGNrequirements to videoconferencing and
文摘With the experience of over 250 beating hear operations since Feb 1995 westarted minimally invasive revascularization of the LAD(MIDCAB).SinceFeb.1996 we operated upon 182 patients with this procedure Since June1996 we treated 40 patients with multivessel discase with a Hybridproccdurc(PTCA plus MIDCAB)The age of the patients ranged between 68 and 79 years.29 patients waremaic.28 patiens suffered from a double vessel discase.12 patients fromtriple vessel discase.The left ventricular ejeetion fraction was loss then 40%in 8 cases 2 patients underwent a reoperativc procedure.Further risk factorswere COLD(n=9).recent MI(n=6),renal insufliciency(n=13).Diabeiesinellitus(n-12).The left mammary was prepared in the usual manner.As access wechese a partial inferior sternotomy(n=4)or a lateral minithoracotomy(n=36).The anastomosis was performed on the beating heart.In all patients we conneeted the LIMA to the LAD.All patients survived andcould be discharged on the 6th postoperative day(mean).In two patients arevision due to bleeding became necessary.Two patients reccived a bloodtransfusions.Postoperatively 15 patients reccived a PTCA of the RCX.4 astentimplantation to the Rex.16 a PTCA of the RCA.5 a stentimplantationto the RCA and 3 patients a PTCA of a D1.3 patients developed a falscaneurysm after the cathcter intervention.By performing the nunimally invasive proeedure the trauma caused bycxtracorporeal circulation can be avoided.Through the combination withPTCA a less invasive therapy of coronary multivessel discase becomespossible in select patients.Postoperative complications and hospital stay canbe teduced.
文摘Objective: Acute kidney disease develops 16% - 30% of patients with preoperative impaired renal functions. Our aim of this study was to compare postoperative renal outcomes using two open heart surgery techniques, on-pump beating heart (OPBH) and conventional on-pump (COP), in patients who have preoperative low glomerular filtration rate (eGFR) as an indicator of creatinine clearance. Methods: From 2004 to 2015, 341 patients with preoperative creatinine clearance were lower than 90 ml/min/1.73m2 were selected for this study. On-Pump beating heart was performed in 111 patients (Group I). Conventional on-pump technique was used in 200 patients. In the remaining patients, we measured postoperative Tumor Necrosis Factor Alpha (TNF-alpha), cardiac troponin I (cTn-I), Brain natriuretic peptid (NT-Pro- BNP), creati-nine (Cr), blood urea nitrogen (BUN) and postoperative eGFR daily until day four after surgery. Results: There were no differences in baseline levels of TNF-alpha, NT-Pro-BNP, BUN, cTn-I, Cr levels between the groups. Cardiopulmonary bypass (CPB) time were much longer and cumulative inotrope use was significantly higher in patients underwent COP (P Conclusion: Our study showed that on-pump beating heart CABG technique provides a morbidity benefit and is associated with a lower risk of peroperative LOS in patients with mild renal disfunction. Our study results suggest that OPBH is superior to the COP in terms of postoperative renal injury and cardiac mediators.
文摘More than any other time of the year,everyone is shopping and nobody wants to overpay because they missed out on a coupon or promo code.Customers have found the easiest way to save is by downloading a smartphone app.But after the transaction is completed...they hit the delete button.This dance doesn’t play out only during the holidays,though.Savvy consumers do this all year long-leaving brands and retailers to wonder how
文摘Background Off-pump coronary artery bypass grafting (CABG) is becoming increasingly popular world - wide. But it is not always feasible. Current cardioplegic techniques do not consistently avoid myocardial ischemic damage. So we use on pump beating heart technique to supplement off-pump CABG. Methods Based on 860 off-pump CABG cases between Aug 1998 to Aug 2000. From Aug 1999 to Aug 2000, 46 CABG cases were performed with on pump beating heart technique at Mani-pal Hospital Heart Foundation, Bangalore, India. All surgeries were performed through a median sternotomy. Exposure techniques were tailored to individual vessels and cardiac regions and local immobilization was performed with octopus. Vascular control was achieved with occluders and shunts. Total cardiopulmonary bypass (CPB) was established before or during CABG and normolthemia was used. Results Among 46 on -pump beating heart CABG patients, 26 patients used CPB before or during OP - CABG because of unstable hemodynamics and electric instability , 7 had very deep intramyocardial left anterior descending arteries, 5 patients had poor LV function (LVEF < 30 % ), 8 patients had cardiomegaly. The average number of grafts was 3.5. No operative mortality. Three patients had postoperative myocardial infarction. Anesthetic time 4. 5±1. 2 hours, extubation time 10±2. 5 hours, blood lost 680±230 mL, blood requirement 540±150 mL, preoperative LVEF 50. 3±13 % , postoperative LVEF 64. 1±14 %, ICU stay 1. 5±0. 5 days, hospi- tal stay 9.2±1.8 days. Conclusion Complete coronary revascularization with on pump beating heart is a supplement for off - pump CABG when it is not feasible. It eliminates intraoperative globe myocardial ischemia and avoids transient myocardial injury during cardioplegic arrest and myocardial reperfusion.
文摘Background Cardiopulmonary bypass (CPB) produces a well documented diffuse inflammatory response that affects multiple organ systems. To avoid the deleterious effects of cardiopulmonary bypass, off pump coronary artery bypass grafting is becoming increasingly popular world wide. We reviewed our experience of complete coronary artery revascularization on the beating heart without CPB. Methods From Aug 1998 to Aug 2000, 860 off pump revascularizations (99%since January 1999) were performed at Manipal Hospital Heart Foundation. The patients consist of males 757(88%), females 103(12%). Averaged age 64.2±15 years. All surgeries were performed through a median sternotomy. Exposure techniques are tailored to individual vessels and cardiac regions. Local immobilization is performed with octopus. Vascular control is achieved with occluders and shunts. Results Among 860 off pump CABG patients. Single graft 72 (8.3%), two grafts 208 (24.2%), three grafts 469 (54.5%), four grafts 101 (11.8%), five graft 10 (1.2%). The average number of grafts per patient was 2.72±0.32. Operative mortality was 0.69%(6 patients). Anesthetic time 3.9±1.2hours, extubation time 6±2.5 hours, Blood requirement 360±90 ml, Preoperative LVEF 60.2±8.5%, Post LVEF 64.1±14%Low cardiac output 48 patients (5.6%), IABP requirement: 25 patients(2.9%), 25 patients converted to CPB during OP CAB(2.9%)and 20 of them were done with on pump beating heart. 25 patients showed myocardial ischemic and 16 patients showed perioperative myocardial infarction. ICU stay 1.1±0.8 days, hospital stay 6.2±1.1 days. Conclusion Off-pump coronary artery bypass in complete revascularization is a safe, effective technique and suitable.
文摘Vienna Symphony Orchestra Concert Vienna Symphony Orchestra Date:May 29-31,2023 Venue:National Center for the Performing Arts With a rich history steeped in tradition,the courage to stand apart and an enduring joy of discovery,the Vienna Symphony Orchestra is the beating heart of Vienna—the metropolis of classical music.For 120 years,the orchestra shaped the special sound of its native city,forging a link between past,present,and future like no other.
文摘上世纪90年代后期以来,“在路上”成为中国文学界的流行话语,它源于“垮掉的一代”(BG)作家凯鲁亚克的小说《在路上》(On the Road),其起源语境、语义与BG相关。小说中BG伙伴横穿美国,在路上酗酒、吸毒、滥交,反抗美国现存体制,体验主流文化之外另一种生活。他们为一种莫名的想望不知疲倦地奔走,在疯狂中感觉自我,所以“在路上”语义非常复杂。中国移植者将它从其起源语境中剥离出来,抽空其原义,对其作望文生义的理解,使其抽象化、普泛化,弱化了它对于中国文化建构的价值与意义。
文摘This paper studies post-war America around the 1950's when On the Road was written and analyzes the protagonist Dean Moriarty as a spokesman of the Beat Generation.He is a typical beat who revolts against the traditional social values and chases after the spiritual complacency.In addition,he opposes wars and advocates the equality between men and women.Thus in a sense Dean is a rebellious hero and stands ahead of his age.