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OBJECTIVES Moderate hypothermic circulatory arrest (MHCA) with selective antegrade cerebral perfusion (SACP) is safe and efficient in total arch replacement and frozen elephant trunk (TAR and FET) for acute type A aortic dissection (ATAAD). But complications related to hypothermia and ischemia are inevitable. The aortic Arch-clamping technique is performed to elevate the lowest nasopharyngeal temperature to 28℃ and shorten the circulatory arrest time. The aim is to evaluate the efficacy of this new technique. METHODS From December 2019 to May 2022, the clinical data of patients with ATAAD who underwent TAR and FET was reviewed, including Arch-clamping in 54 cases and MHCA/SACP in 149 cases. RESULTS Circulatory arrest time was significantly decreased in the aortic Arch-clamping group (4.09 ± 1.696 min vs. 23.94 ± 6.738 min, P

T cell-mediated immune response plays a key role in Takayasu arteritis (TAK). Although previous studies have showed the roles of CD4+T cell and its subsets in TAK, the change of CD8+ T cell subsets remains unclear. This study investigated the role of CD8+ T cell subsets in TAK. The study consisted of 56 TA patients and 51 healthy controls. The percentages of CD8+T cells, CD8+GranzymeB+ T cells, CD8+Perforin+ T cells, and CD8+IFN-γ+ T cells in blood samples were analyzed by flow cytometry. We found that the percentages of CD8+GranzymeB+ T cells (P = 0.030), CD8+Perforin+ T cells (P = 0.000), and CD8+IFN-γ+ T cells (P = 0.002) in CD8+T cells were higher in TAK patients compared to control group. After 6 months of treatment, the proportion of CD8+T cells in lymphocytes were significantly lower in TAK patients than the baseline assessment (P = 0.033). A lower ratio of CD8+GranzymeB+ T cells/CD8+ T cells were showed in TAK patents after treatment compared with TAK patients before treatments (P = 0.011). The change of CD8+GranzymeB+ T cells/CD8+ T cells ratio was positively correlated with the change of ITAS (r = 0.721, P = 0.002) and ITAS-A (r = 0.637, P = 0.008). Finally, the immunofluorescence staining showed the infiltration of CD8+ Granzyme B + cells in the aortic tissue of TAK patients. Our results disclose that the CD8+ T lymphocytes may play a role in TAK pathogenesis. Targeting CD8+GranzymeB+ T lymphocytes or Granzyme B inhibitors could be a potential therapeutic approach for the treatment of TAK.

New findings What is the central question of this study? Insulin-like growth factor 1 and its major binding protein insulin-like growth factor binding protein 3 (IGFBP3) are involved in collagen deregulation in several cardiovascular diseases: what is the role of IGFBP3 in thoracic aortic dissection and does it regulate aortic smooth muscle cells' phenotypic switch? What is the main finding and its importance? IGFBP3 inhibits aortic smooth muscle cells' phenotypic switch from a contractile to a synthetic phenotype, decreases matrix metalloproteinase 9 activation and suppresses elastin degradation. These findings provide a better understanding of the pathogenesis of thoracic aortic dissection. Abstract Thoracic aortic dissection (TAD) is characterized by aortic media degeneration and is a highly lethal disease. An aortic smooth muscle cell (AoSMC) phenotypic switch is considered a key pathophysiological change in TAD. Insulin-like growth factor binding protein 3 (IGFBP3) was found to be downregulated in aortic tissues of TAD patients. The present work aimed to study the function of IGFBP3 in AoSMCs' phenotypic switch and matrix metalloproteinase (MMP) expression. We established a mouse model of TAD by angiotensin (Ang) II infusion to β-aminopropionitrile-administrated mice, and found decreased IGFBP3 expression accompanied by aortic dilatation and elastin degradation in vivo. Further, mouse (m)AoSMCs were isolated from mouse thoracic aorta and treated with Ang II. Ang II induced downregulation of IGFBP3 in vitro. To further study the function of IGFBP3, primary mAoSMCs were infected with adenovirus expressing IGFBP3 followed by Ang II induction. Enforced upregulation of IGFBP3 decreased MMP9 expression and activation as well as increasing tissue inhibitor of metalloproteinase (TIMP) 1 expression in Ang II-induced mAoSMCs. No difference was observed in MMP2 and TIMP3 expression. IGFBP3 suppressed subsequent Ang II-induced elastin degradation in vitro. IGFBP3 inhibited Ang II-induced mAoSMCs' phenotypic switch as evidenced by increased smooth muscle actin α-2 (ACTA2) and myosin heavy chain 11 (MYH11) expression and decreased secreted phosphoprotein 1 (SPP1) and vimentin expression. Taken together, the present study demonstrates the role of IGFBP3 in preserving AoSMCs' contractile state and reducing MMP9 activation and thus promoting elastic fibre synthesis, which provides a better understanding of the pathogenesis of TAD.

OBJECTIVES Pregnancy-related aortic dissection (AoD) in Marfan syndrome is a lethal catastrophe. Due to its rarity and limited clinical experience, there is no consensus regarding the optimal management strategy. We seek to present our 21-year experience in such patients , focusing on management strategies and early and late outcomes. METHODS Between 1998 and 2019, we managed 30 pregnant women with Marfan syndrome (mean age 30.7 ± 4.3 years) who sustained AoD at a mean of 28.3 ± 8.8 weeks of gestation (GWs). AoD was acute in 21 (70%), type A (TAAD) in 24 (80%) and type B (TBAD) in 6 (20%). Fourteen TAADs (58.3%, 14/24) and 2 TBADs (33.3%, 2/6) occurred in the third trimester or postpartum. The maximal aortic size was < 45 mm in 26.7% (8/30; 3 TAADs, 5 TBADs). Management strategy was based on the types of dissection and GWs (i.e. surgical versus medical treatment, surgery or delivery first). RESULTS TAADs were treated medically in 1 and surgically in 23. The timing of delivery and surgery were caesarean first at 35.4 ± 6.1 GWs in 7 (29.2%), followed by surgery after mean 46 days; single-stage C-section and surgery at 32.0 ± 5.0 GWs in 10 (41.7%); and surgery first at 18.0 ± 5.8 GWs in 6 (25%), followed by C-section after 20 days. Maternal and foetal mortality were 28.6% (2/7) and 14.3% (1/7), 10.0% (1/10) and 20.0% (2/10) and 16.7% (1/6) and 83.3% (5/6), respectively. Five TBADs (83.3%) were managed with C-section followed by surgery in 2 and medical treatment in 3. The respective maternal and foetal mortality were 50% (1/2) and 100% (2/2) and 33.3% (1/3) and 33.3% (1/3), respectively. One TBAD was managed surgically first followed by C-section, resulting in maternal survival and foetal death. Follow-up was complete in 95.8% (23/24) at 3.7 ± 2.9 years. Four late deaths occurred and reoperation was performed in 1 patient. Maternal and foetal survival were 64.3% and 54.1% at 6 years, respectively. CONCLUSIONS Management of AoD in pregnant women with Marfan syndrome should be based on types of dissection (surgical versus medical) and gestational age (delivery or surgery first), which largely determine maternal and foetal survival. Aortic repair should be considered prior to conception in women with Marfan syndrome even at diameters smaller than recommended by current guidelines.

Background The etiology of Takayasu arteritis (TA) is unknown; however, a possible relationship between streptococcal infection and TA has been proposed. This study aimed to identify the clinical features and cardiac valvular involvement in untreated TA patients with an elevated antistreptolysin O (ASO) titer. Methods In this retrospective study, the clinical characteristics and features of valvular involvement were compared in TA patients with or without an elevated ASO titer. Results Of the 74 untreated TA patients, 13 patients were found have elevated ASO titers (17.6%). Mitral insufficiency was the most common in patients with elevated ASO (69.2%, 9/13), followed by aortic valve insufficiency (46.2%, 5/13) and tricuspid insufficiency (46.2%, 5/13), which were no significantly different than that in normal ASO group. The proportions of moderate to severe mitral (30.8% vs 1.6%, p = 0.000) and tricuspid valve (15.4% vs 1.64%, p = 0.023) insufficiency in the ASO positive group were significantly higher than those in the ASO negative group. The odds of mitral regurgitation in patients with elevated ASO titers were 3.9 times higher than those in the group with normal ASO titers (p = 0.053, OR = 3.929, 95% confidence interval [CI]: 0.983–15.694). Furthermore, the risk of moderate to severe mitral insufficiency in patients with elevated ASO titers was 41.6 times higher than that in patients with normal ASO titers (p = 0.002, OR = 41.600, 95% CI: 3.867–447.559). Conclusions An increase in ASO titer is related to valvular involvement in TA and is closely linked to mitral insufficiency.

A technique called arch-clamping was used at our institute to ensure perfusion of the lower body and brain during total arch replacement with frozen elephant trunk (TAR and FET). The aortic arch clamp is inserted between the left common carotid artery and the left subclavian artery after inserting the stented elephant trunk into the true lumen of the descending aorta during the procedure, and then clamps the aorta and graft together as the distal anastomotic edge of the aorta. After the arch clamp was in place, lower body perfusion was resumed through the femoral artery was resumed and time to circulatory arrest was reduced to approximately 4 min. Cardiopulmonary bypass (CPB) flow was gradually restored to full rate. Thereafter, the left carotid artery anastomosis was completed and rewarming began. Finally, during the rewarming period, other branches of the aortic arch and ascending aorta were reconstructed. In this paper, we describe the perfusion management strategy, discuss intraoperative monitoring parameters, and examine the feasibility of the technique from a perfusion perspective.

T cell-mediated immune response plays a key role in Takayasu arteritis (TAK). Although previous studies have showed the roles of CD4The study consisted of 56 TA patients and 51 healthy controls. The percentages of CD8We found that the percentages of CD8Our results disclose that the CD8

BACKGROUND: This study analyzes the outcomes of a one-stage hybrid procedure combining thoracic endovascular aortic repair (TEVAR) with extra-anatomic bypass in patients with distal aortic arch disease. METHODS: This retrospective study collected 103 hybrid procedures combining TEVAR with extra-anatomic bypass (mean age, 62.2±9.3 years; 90 males) performed from January 2009 to January 2019 at Beijing Anzhen Hospital. We analyzed 30-day and mid-term outcomes including survival rate and the incidence of stroke, spinal cord injury (SCI), and endoleak. RESULTS: Five deaths (4.6%) occurred within 30 days, including type I endoleak in Zone 1 (n=1), hemorrhagic shock (n=1), stroke (n=2), and stent migration (n=1). Two patients developed SCI. The median follow-up time was 39.5 (interquartile range, 13.6-69.0) months. In all, 14 late deaths occurred; these were due to stroke (n=2), severe pneumonia (n=1), aortic rupture caused by type I endoleak (n=3), and sudden death (n=8). Six late endoleaks occurred including three type I and one type II in Zone 1 and two type I in Zone 2. In a competing risks analysis, the incidences of reintervention at 7 years, late death, and survival without reintervention were 8%, 22%, and 70%, respectively. In a Cox risk model, stroke (HR, 21.602; 95% CI: 2.798–166.796; P=0.003) was the only risk factor for 30-day mortality. Stroke (HR, 19.484; 95% CI: 5.245–72.380; P

Several novel technological developments and surgical approaches have characterized the field of aortic surgery in the recent decade. The progressive introduction of endovascular procedures, minimally invasive surgical techniques and hybrid approaches have changed the practice in aortic surgery and generated new trends and questions. Also, the advancements in the manufacturing of tissue engineered vascular grafts as substitutes for aortic replacements are enlightening new avenues in the treatment of aortic disease. This review will provide an overview of the current novel perspectives, debates and trends in major thoracic aortic surgery.

OBJECTIVES: We seek to report our management protocol and early outcomes of acute type A aortic dissection (ATAAD) repair during the early phase of coronavirus disease 2019 (COVID-19). METHODS: From January 23 to April 30, 2020, we performed ATAAD repair for 33 patients, including three with pregnancy-related TAADs. Confirmation of COVID-19 depended on the results of two nucleic acid tests and pulmonary computed tomography scan. Based on testing results and hemodynamic stability, patients were triaged to an isolated intensive care unit or negative pressure operating room for emergency surgery. RESULTS: Mean age 50.2 ± 13.3 years and 20 were male (60.1%) and 8 patients were febrile (>37.3°C; 24.2%) and 17 were lymphopenic (51.5%). No patient was excluded from COVID-19 infection preoperatively. Extensive aortic repair with total arch replacement (TAR) was performed in 24 (72.7%), and limited proximal repair in 9 patients (27.3%). Cardiopulmonary bypass and cross-clamp times averaged 177 ± 34 and 88 ± 20 min for TAR, and 150 ± 30 and 83 ± 18 min for hemiarch, respectively. The mean operation time was 410 ± 68.3 min. Operative mortality was 6.1% (2/33). Complications included reintubation in four (12.1%), acute kidney failure in two (6.1%), and cerebral infarction in one (3.0%). No paraplegia nor re-exploration for bleeding occurred. COVID-19 was excluded in 100% eventually. No nosocomial infection occurred. Nor did any patient/surgical staff develop fever or test positive during the study period. CONCLUSIONS: The results of this study show that our management protocol based on testing results and hemodynamic stability in patients with ATAAD during the COVID-19 pandemic was effective and achieved favorable early surgical outcomes.

Objectives Aortobronchial fistula (ABF) is rare but lethal condition if left untreated, and the treatment still remains challenging. We retrospectively reviewed data at our Institution and report our experience in the management of ABF. Methods From September 2010 to May 2019, 14 patients (13 men, average age 52 ± 11 years) with ABF were treated in our hospital. Three types of management were applied according to the patients' different clinical presentation, including conservative treatment, that is, antibiotic treatment (n = 3), endovascular repair (n = 7), and open surgery (n = 4). In the open surgery group, Dacron grafts were used, two cases received in situ descending thoracic aortic replacement through left thoracotomy and two cases received extra-anatomic bypass through median thoracoabdominal incision. Results In the conservative treatment group (n = 3), two patients died during follow-up, the third was alive in good condition. In the endovascular repair group (n = 7), one patient died 22 days after the endovascular repair because of massive hemoptysis and another patient died 4 days after the procedure because of cerebral infarction. In the medium term, two patients died of massive hemoptysis, and one was lost at follow-up. In the open surgery group (n = 4), one patient died because of massive hemoptysis 2 days after his extra-anatomic bypass procedure, the remaining patients were alive in good condition at follow-up. Conclusions ABF is catastrophic if left untreated. Endovascular repair might be a reasonable temporary bridge solution in emergency cases, but is less durable in the long run. Open surgery, despite more challenging, provides a more definitive treatment for ABF.

Background: Several methods of arch vessel reconstruction, such as en bloc (island) and branched graft techniques, have been proposed to treat aortic arch pathologies during total arch replacement (TAR). We seek to review our experience with modified en bloc technique and left subclavian (LSCA)-left carotid artery (LCCA) transposition in TAR and frozen elephant trunk (FET) procedure for chronic type A aortic dissection (CTAAD). Methods: From September 2010 to September 2016, 35 consecutive patients with CTAAD underwent modified en bloc arch reconstruction with LSCA-LCCA transposition during TAR and FET procedure. Computed tomographic angiography (CTA) was performed during follow-up. Results: In-hospital mortality was 5.7% (2/35). No neurological deficit or spinal cord injury occurred. Re-exploration for bleeding and continuous renal replacement therapy were required in 2 patients each (5.7%). Follow-up was complete in 100% for a mean duration of 4.1±1.8 years (range, 0.5–6.7 years). One patient experienced a transient stroke and thoracoabdominal aortic replacement was performed in 1. There were 2 late non-cardiac deaths. Survival was 87.9% (95% CI, 70.7–95.3%) at 6 years. At 6 years, the incidence was 3% for reoperation, 12% for late death, and 85% of patients were alive without reoperation. The anastomosis between the LSCA and LCCA was patent in 100%. Conclusions: Acceptable early and mid-term outcomes were achieved for patients with chronic type A dissection using en bloc technique with LSCA-LCCA transposition during TAR and FET procedure. This technique may be an alternative approach to chronic type A dissection in selected patients.

Background Aortic dissection in pregnancy is a rare but lethal catastrophe. Clinical experiences are limited. We report our experience in 25 patients focusing on etiology, management strategies, and outcomes. Methods Between June 1998 and February 2015, we treated 25 pregnant women (mean age, 31.6 ± 4.7 years) in whom aortic dissection developed at a mean of 28 ± 10 gestational weeks (GWs). Type A aortic dissection (TAAD) was present in 20 (80%) and type B (TBAD) in 5 (20%). Marfan syndrome was seen in 17 (68%). Management strategy was based on dissection type and GWs. Results TAADs were managed surgically in 19 (95.0%) and medically in 1 (5.0%). Maternal and fetal mortalities were, respectively, 14.3% (1 of 7) and 0 (0 of 7) in the "delivery first" group (7 of 20), 16.7% (1 of 6) and 33.3% (2 of 6) in "single-stage delivery and aortic repair" group (6 of 20), 16.7% (1 of 6) and 66.7% (4 of 6) in "aortic repair first" group (6 of 20), and 100% (1 of 1) and 100% (1 of 1) in the "medical management" group (1 of 20). TBADs were managed surgically in 60% (3 of 5) and endovascularly and medically in 20% each (1 of 5). No maternal deaths occurred. Fetal mortality was 100% in the surgical group and 0% in the other groups. During late follow-up, which was complete in 95.2% (20 of 21), 3 maternal and 2 fetal deaths occurred in the TAAD group. Overall maternal survival was 68.6% at 5 years. Conclusions Marfan syndrome predominates among women with aortic dissection in pregnancy. For TAADs, after 28 GWs, delivery followed by surgical repair can achieve maternal and fetal survival adequately; before 28 GWs, maternal survival should be prioritized given the high risk of fetal death. For TBADs in pregnancy, nonsurgical management is preferred.

The MgO-V2O5 and CaO-V2O5 systems in air have been critically evaluated and thermodynamically assessed based on available experimental data. The liquid phase is described by the modified quasichemical model and all intermediate phases are treated as stoichiometric compounds. A set of self-consistent model parameters for all phases in both systems is obtained. The experimental phase equilibria and thermodynamic data in air are well reproduced within experimental error limits.

Based on the experimental phase equilibria and thermodynamic data, a critical evaluation and thermodynamic assessment of the PbO–V2O5 system has been performed. The liquid phase is described by the modified quasichemical model, which takes short-range ordering in liquid solution into account. All intermediate phases are treated as stoichiometric compounds. A set of self-consistent thermodynamic functions for all phases in the PbO–V2O5 system is obtained. The available phase equilibria and thermodynamic data are reproduced well within experimental error limits.

Background: Acute aorta dissection (AD) is a fatal emergency, however, studies addressing the clinical characteristics, management, and outcome of acute AD in young adult patients aged under 45 yea...

Cervical aortic arch (CAA) is rare and difficult to repair. Clinical experience is limited. We report the surgical techniques and midterm outcomes in 35 patients with CAA based on an alternative classification scheme.Of 35 patients with CAA, 30 (85.7%) had left-sided aortic arch and 5 had (14.3%) right-sided aortic arch (all 5 had a vascular ring). Mean age was 34.2 ± 13.1 years, 23 were female (65.7%), and 18 were asymptomatic (51.4%). Surgical access and procedure were chosen according to an alternative classification scheme that is based on the presence or absence of vascular ring and relationship of descending aorta to the side of the aortic arch. In the left-sided aortic arch group, aortic arch reconstruction though median sternotomy was performed in 15 patients, and distal arch and descending thoracic aortic replacement via left thoracotomy in 15 patients. In the right-sided aortic arch group, ascending-to-descending aortic bypass was done via median sternotomy in 2 patients and right thoracotomy in 1, and distal arch and descending thoracic aortic replacement via right thoracotomy in 2 patients.Neither death nor spinal cord injury occurred. Left recurrent laryngeal nerve injury, prolonged ventilation, and reexploration for bleeding occurred in 1 each. In 11 patients with coarctation, the upper-lower limb gradient decreased significantly postoperatively (from 34.0 ± 12.7 to 10.2 ± 2.7 mm Hg; P .01). The diseased aortic segment was excluded in 34 patients, except 1 with residual aneurysm in the proximal descending thoracic aorta. Follow-up was complete in 100% at mean 4.4 ± 2.0 years. No late death, limb ischemia, or stroke occurred. Endovascular repair was performed in 1 patient, and ascending aortic dilation occurred in 1 patient. The residual aorta remained nondilated in 33 patients. Aortic grafts were patent in 100%, with no anastomotic leak or pseudoaneurysm. At 6 years, the incidences of death, aortic events, and event-free survival were 0%, 6.5%, and 93.5%, respectively.Open repair of CAA can achieve favorable early and midterm outcomes. Surgical accesses and procedures should be chosen based on type of CAA, anatomic variations and associated anomalies. Our alternative categorization scheme of CAA is intuitive and comprehensive, which may facilitate classification and surgical decision making.

Based on phase equilibria, thermodynamic, and crystal structure data, the thermodynamic modeling of HfO2–La2O3–Al2O3 system is presented. Liquid phase is described by the modified quasichemical model considering the short-range ordering in liquid solution. Solid solutions are described by the ionic sublattice model considering respective crystal structure. The model (La3+, Hf4+)2(Hf4+, La3+)2(O2−, Va)6(O2−)1(Va, O2−)1 successfully describes the structure defect, homogeneity range, and thermodynamic property of pyrochlore solid solution. A set of optimized model parameters is obtained which reproduces most experimental data well. Isothermal sections, liquidus and solidus projections, and Scheil reaction scheme are constructed.

The V–O system has been critically evaluated and thermodynamically assessed based on the available phase diagram and thermodynamic data using the CALPHAD method. The liquid phase over the whole composition range from metallic liquid to oxide melt is described by the modified quasichemical model with five species: VII, VIII, VIV, VV and O, which takes short-range ordering in liquid solution into account. All solid solutions are modeled considering respective crystal structures. A set of self-consistent thermodynamic parameters of the V–O system is obtained and the available experimental data are reproduced well within experimental error limits. Especially for the VOx solid solution, the site fractions of vacancies in both vanadium and oxygen sublattices are reproduced well using the present model and parameters.

The R2O–P2O5 (R = Li, Na and K) systems are thermodynamically optimized based on the evaluated phase equilibria and thermodynamic data by the CALPHAD method. Liquid phase is described by the Modified Quasichemical Model, which takes short-range ordering in liquid solution into account. All intermediate phases RPO3, R5P3O10, R4P2O7 and R3PO4 are treated as stoichiometric compounds and the corresponding polymorphic transitions are considered. A set of self-consistent model parameters for describing the Gibbs free energy of each phase are obtained. The experimental phase equilibria, enthalpy of formation, entropy, heat capacity and activity are reproduced well within experimental error limits. The calculated liquidus around compounds become flatter with the increase of P2O5 content, suggesting that the degree of stability of phosphate increases as its composition approaches R3PO4. The calculated enthalpies of formation for intermediate compounds become more negative and entropies become more positive with the increase of atomic numbers of alkali metals.

To analyze the clinical outcome of corticosteroid and/or immunosuppressive treatment preoperatively in patients with Takayasu's arteritis.Forty-six patients with Takayasu's arteritis who received cardiovascular surgery between January 2010 and December 2015 in Beijing Anzhen Hospital were enrolled in this study. Their clinical characteristics, preoperative drug therapy, surgical treatment, and pathological examination results were retrospectively analyzed for the effect of drugs on outcome of the surgery.All 8 patients with active disease prior to surgery had postoperative complications including one death due to stubborn perivalvular regurgitation induced heart failure during the perioperative period. Among 38 patients without active disease prior to surgery, only 4 patients (10.5%) had postoperative complications. Thirty-four patients showed symptomatic relief in the perioperative period, of whom 23 patients treated with corticosteroid and/or immunosuppressive agents preoperatively.The surgery can effectively improve the symptoms of patients with Takayasu's arteritis. Active disease of Takayasu's arteritis markedly increased risk for postoperative complication and resulted in poor outcome of the surgery. Treatment with corticosteroid and/or immunosuppressive agents before surgery can effectively control the patient's condition, improve the rate of remission, and effectively reduce the incidence of postoperative complications.

Based on the critical evaluation of available phase diagram, thermodynamic, and crystal structure data, the ternary Ti-C-O system is thermodynamically assessed using the Calculation of Phase Diagram method. Both binary Ti-C and Ti-O systems are reassessed to obtain the successful description of ternary Ti-C-O system for the first time. The liquid phase is described by the modified quasichemical model, which takes short-range ordering in liquid solution into account. All solid solutions are described using compound energy formalism. In particular, a completed solid solution between TiC x and TiO y with the excess solubilities of Ti, C, and O is accurately described with the (Ti, Va)1(C, O, Va)1 solution structure. The thermodynamic models with a set of optimized self-consistent model parameters can reproduce available reliable experimental data within experimental error limits. The results are also applied to the thermodynamic analysis of complex carbothermic TiO2 reduction process.

Bi-alkali metal (Li, Na, K, Rb) binary systems have been systematically assessed based on the available phase diagrams and thermodynamic data. The modified quasichemical model, which takes short-range ordering into account, is used to describe the liquid phase. All intermetallic phases are treated as stoichiometric compounds. A set of self-consistent model parameters is obtained and the experimental data are reproduced well within experimental error limits. The enthalpy of mixing, entropy of mixing, and activity of element are calculated, showing the liquid phase exhibits maximum short-range ordering at 75 at% X (X=Li, Na, K, Rb). Some systematic variations and regularities are presented, indicating the enthalpy and entropy of mixing for the liquid phase at the maximum short-range ordering along with the enthalpy of formation and melting temperature of intermediate compound BiX3 change with the atomic radius of alkali metals regularly.

Thermodynamic assessment of the In-Ni-Sb ternary system has been performed using the CALPHAD technique. The phases ζ(Ni2In) and ζ(NiSb) with the same B8-type structure in the subbinary systems are modified using the same three-sublattice model: (Ni,Va)1/3(Ni,Va)1/3(Ni,X)1/3 (X = In, Sb), in order to give the continuous solid solution phase ζ in the In-Ni-Sb ternary system a better description. This modification is also made to the Gibbs free energy expression of the InSb phase. The parameters of the thermodynamic descriptions of the In-Ni-Sb ternary system are optimized on the basis of the three modified subbinary systems. A set of self-consistent thermodynamic parameters of the In-Ni-Sb system is obtained according to five isothermal sections and three vertical sections. Most of the experimental data can be satisfactorily reproduced by the present parameters. The liquidus projection and the invariant reactions are also presented. By simply considering the standards of melting temperature and thermodynamic stability, part of the ζ-phase is more suitable as a contact material to InSb semiconductor.

The binary phase diagrams of the YCl3–ACl (A=Li, Na, K, Rb, Cs) systems were studied using the CALPHAD technique and nonlinear mathematical method. The new modified quasi-chemical model in the pair-approximation for short-range ordering was applied to describe the Gibbs energies of the liquid phase in these systems. And the paper created the Artificial Neural Networks (ANN) model to study the interaction coefficients of two ending compounds composing the binary systems which are important for thermodynamic study of multi-elements system. Based on measured phase equilibrium data, a set of thermodynamic functions has been optimized and calculated. The effects of ionic radius, electronegativity and mole fraction of YCl3 on interaction coefficients were investigated in more detail.

Background We evaluated an open stented elephant trunk (sET) technique combined with cardiac operations for a one-stage treatment of patients with complicated Stanford type B aortic dissection (AoD) and cardiac diseases. Methods Between April 2007 and March 2010, 16 patients with Stanford B AoD and cardiac diseases (mean age 49.75 ± 13.42 years) underwent sET combined with cardiac operations. Under deep hypothermic cardiac arrest (DHCA), a stented graft was directly delivered via the incision of aortic arch and the proximal graft was sutured on the normal distal aortic arch wall in a continuous circumferential full-thickness fashion. The combined cardiac operations (Bentall procedure, etc.) were performed before sET implantation while cooling. Results Average time of cardiopulmonary bypass, aortic cross clamping durance, and DHCA was 131.62 ± 23.85, 64.69 ± 9.72, and 21.94 ± 3.60 minutes, respectively. There were no early deaths and no neurological complications. During a follow-up of 18.69 ± 9.94 months, computed tomographic angiography was performed in all patients. Neither endoleak nor stent shifting was observed. Retrograde type A AoD was not found during follow-up. Thrombus was formed in the false lumen from the proximal descending aorta to the diaphragmatic section. Conclusions The open sET technique combined cardiac procedures can reliably treat Stanford type B AoD concomitant with surgical cardiac disease in a single stage.

In the original article, there are three errors in the parameters listed under ω(NiIn): (Ni, Va)0.5(In, Ni)0.5 in Table␣II.

The knowledge of phase diagram and thermodynamic properties of the Si-Ta and Si-W systems is of technical importance for metallic contacts between Ta, W, and SiC in electrical and electronic devices. The phase diagram and thermodynamic properties of the Si-Ta and Si-W systems were assessed using the CALPHAD approach with available experimental data. The intermetallic compounds of the two systems were modeled as stoichiometric ones. A set of self-consistent thermodynamic parameters were obtained and the calculated phase equilibria were found to be in reasonable agreement with most experimental data. The calculated enthalpies of formation of the silicides in the Si-Ta and Si-W systems were compared with the reported values. The enthalpies of mixing of liquid at 2000 K in similar Si-transition metal systems were used for comparison in order to judge the rationality of the calculations. The assessed thermodynamic descriptions of the Si-Ta and Si-W binary systems will serve as part of the thermodynamic database for the Si-C-M (M: Ta and W) alloys.

The Gibbs energies of liquid phases in the LaI 3 -MI (M= Na, K, Cs) systems were described by the modified quasi-chemical model. From the measured phase equilibrium data of these binary systems, a set of thermodynamic functions were optimized by using the CALPHAD technique. The enthalpy of mixing and the interaction parameter of the liquid phase were predicted from known data for the LaI 3 -MI systems.

According to measured experimental phase diagram data and thermodynamic data, the HoCl3-MCl (M = Na, K, Rb, Cs) phase diagrams were determined by the CALPHAD technique. The Gibbs energies of liquid phases in these systems have been optimized and calculated by the modified quasi-chemical model in the pair-approximation for short-range ordering. A series of thermodynamic functions have been optimized and calculated on the basis of an interactive computer-assisted analysis. The results show that the thermodynamic properties and phase diagrams are self-consistent. The optimized results for the systems are discussed.

YbCl3-MCl (M = Na, K, Rb, Cs) systems were optimized and calculated using the CALPHAD (CALculation of PHAse Diagram) technique. The modified quasi-chemical model in the pair-approximation for short-range ordering was used to describe the Gibbs energies of liquid phase in the systems. On the basis of the measured phase diagram data and experimental thermodynamic properties, a series of thermodynamic functions were optimized and calculated through an interactive computer-assisted analysis. Furthermore, some reasonable discussions on the thermodynamic parameters for these strong interaction binary systems were carried out. The results showed that the optimized parameters and experimental data are thermodynamically self-consistent.

Thermodynamic activities of aluminum in the iron–aluminum system were determined between about 720 and 850 K for the composition range between 23 and 33 at.% Al which includes the D0 3 -ordered nonstoichiometric intermetallic compound Fe 3 Al. For this purpose an electromotive force method with a single-crystal CaF 2 electrolyte was used, and the following cell arrangement was employed: (−)Pt|Ir|Al 0.85 Sn 0.15 , Na 3 AlF 6 |CaF 2 |Al 1± x Fe 3± x , Na 3 AlF 6 |Ir|Pt (+). Activities of iron were obtained by means of a Gibbs-Duhem integration for the same composition range. The results of the activity measurements were interpreted in terms of a statistical–thermodynamic model for nonstoichiometric phases with the D0 3 -superstructure based on defect formation energies from the literature. It was found that non-stoichiometry in Fe 3 Al is caused by anti-structure atoms on two of the three possible sublattices.

The activities of Sn of liquid Ag–Bi–Sn alloys for three cross-sections with the constant molar ratios of Ag:Bi = 2:1, 1:1, and 1:2 are measured at 627 and 727 ∘ C by an electromotive force (emf) method with a liquid electrolyte. The previous thermodynamic descriptions of the Ag–Bi–Sn ternary system are modified by considering the literature data and our own experimental results. The thermodynamic interaction parameters of the Bi–Sn binary and the Ag–Bi–Sn ternary liquid phase are optimized using the emf and calorimetric data from the present work. Based on the self-consistent optimized thermodynamic parameters the phase diagram and thermodynamic properties of the Ag–Bi–Sn ternary system are calculated and compared with the experimental data. The agreement between the calculated results and the experimental data has been significantly improved.

The Al2O3-SrO binary system has been studied using the CALPHAD technique in this paper. The modeling of Al2O3 in the liquid phase is modified from the traditional formula with the liquid phase represented by the ionic two-sublattice model as (Al3+, Sr2+) P ( $${\hbox{AlO}_{2}^{1-}}$$ , O2−) Q . Based on the measured phase equilibrium data and experimental thermodynamic properties, a set of thermodynamic functions has been optimized using an interactive computer-assisted analysis. The calculated results are compared with experimental data. A comparison between this system and similar systems is also given.

Surface tensions of the Sn–Ga–In ternary alloy are calculated from the surface tensions of the Sn–Ga, Ga–In and In–Sn sub-binary systems by using geometric models (the Kohler model and the Toop model), and a general solution model (the Chou model). The calculated results are in excellent agreement with the experimental data (except for the Kohler model), assuming an experimental accuracy of ±2.5%. At the same time, the surface tensions of the Sn–Ga–In ternary alloy at 773 K and their sub-binary systems are predicted on the basis of Butler’s equation, in combination with thermodynamic data, and different model parameters β equal to the ratio of the coordination number in the surface phase to that in the bulk phase. Different values of β have almost no influence on the surface tensions. The predicted results agree with the experimental data. Therefore, the resulting iso-surface tension curves for the Sn–Ga–In ternary alloy at 773 K, especially those calculated by using the Toop model, are reasonable.

A series of the mixed transition metal compounds, Li[(Ni1/3Co1/3Mn1/3)1–x-y Al x B y ]O2-z F z (x = 0, 0.02, y = 0, 0.02, z = 0, 0.02), were synthesized via coprecipitation followed by a high-temperature heat-treatment. XRD patterns revealed that this material has a typical α-NaFeO2 type layered structure with R3- m space group. Rietveld refinement explained that cation mixing within the Li(Ni1/3Co1/3Mn1/3)O2 could be absolutely diminished by Al-doping. Al, B and F doped compounds showed both improved physical and electrochemical properties, high tap-density, and delivered a reversible capacity of 190 mAh/g with excellent capacity retention even when the electrodes were cycled between 3.0 and 4.7 V.

In this article, following a brief introduction concerning experimental measurements of surface and interfacial tensions, methods for calculating surface tension and surface segregation for binary, ternary, and multicomponent high-temperature melts based on Bulter's original treatment [1] and on available physical properties and thermodynamic data, especially excess Gibbs free energies of bulk phase and surface phase versus temperature obtained from thermodynamic databases using the calculation of phase diagram (CALPHAD) approach, with special attention to the model parameter, have been described. In addition, the geometric models can be extended to predict surface tensions of multicom-ponent systems from those of sub-binary systems. For illustration, some calculated examples, including Pb-free soldering systems and phase-diagram evaluation of binary alloys in nanoparticle systems are given. On the basis of surface tensions of high-temperature melts, interfacial tensions between liquid alloy and molten slag as well as molten slag and molten matter can be calculated using the Girifalco-Good equation [2]. Modifications are suggested in the Nishizawa's model [3] for estimation of interfacial tension in liquid metal (A)/ceramics (MX) systems so that the calculations can be carried out based on the sublattice model and thermodynamic data, without deliberately differentiating the phase of MX at high temperature. Finally, the derivation of an approximate expression for predicting interfacial tension between the high-temperature multi- component melts, employing Becker's model [4] in conjunction with Bulter's equation and interfacial tension data of the simple systems is described, and some examples concerning pyrometallurgical systems are given for better understanding.

The Al 2 O 3 –BaO binary system has been studied using the CALPHAD technique in this paper. The modeling of Al 2 O 3 in the liquid phase is modified from the traditional formula with the liquid phase represented by the ionic two-sublattice model as (Al 3+ , Ba 2+ ) P (AlO 2 1− , O 2− ) Q . Based on the measured phase equilibrium data and experimental thermodynamic properties, a set of thermodynamic functions has been optimized using an interactive computer-assisted analysis. A comparison between the calculated results and experimental data is presented.

In this paper, the binary phase diagrams of the ErCl3–MCl (M = Li, Na, K, Rb, Cs) systems were studied by the CALPHAD (CALculation of PHAse Diagram) approach. The modified quasi-chemical model in the pair-approximation for short-range ordering was used to describe the Gibbs energies of the liquid phase in the systems. From measured phase diagram data and experimental thermochemical properties, a series of thermodynamic functions has been optimized based on computer-assisted analysis. A discussion of thermodynamic functions for strong interaction binary systems was undertaken. The results showed that the calculated phase diagrams and optimized thermodynamic parameters are self-consistent.

The surface tension of molten Sn-Bi (mole fraction X-Bi = 0.455) alloy has been determined by the sessile drop method at oxygen partial pressure (P-O2) of 1.0 X 10(-6) MPa and different temperatures. The experimental results have been analyzed and discussed, and the positive temperature coefficient Of surface tension of molten Sn-Bi alloy has been elucidated. The surface tension of this molten alloy has also been obtained by calculation Using STCBE based on Butler's equation and thermodynamic data. The experimental results agree well with the calculation values. (c) 2005 Elsevier Inc. All rights reserved.

Zinc vapor pressures over binary Pt–Zn alloys were determined in the composition range from 63 to 84 at.% Zn for temperatures between 840 –1150 K using an isopiestic method. The phase boundaries of four different phase fields in this composition range could be fixed based on the experimental data. Thermodynamic activities and partial molar enthalpies of zinc within these phase fields were derived from the vapor pressure data and the composition dependence of the zinc activity was calculated for 1023 K. The integral Gibbs energy at 1273 K was derived as a function of composition by Gibbs–Duhem integration, combining the activity data of the present investigation with earlier results from the literature.

An optimization of the binary GdCl 3 –ACl (A=Na,K,Rb,Cs) systems has been carried out using the CALPHAD technique. The new modified quasi-chemical model in the pair-approximation for short-range ordering was used to describe the Gibbs energies of the liquid phase in these systems. Based on the measured phase equilibrium data and experimental thermochemical properties, the GdCl 3 –ACl phase diagrams were optimized and calculated. A set of thermodynamic functions has been optimized based on an interactive computer-assisted analysis. The calculations based on the obtained descriptions show good agreement with experimental phase diagrams and thermodynamic values.