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Isothermal uniaxial compression experiments were performed in the range of 300–450 °C and 0.001 to 10 s−1 to clarify the hot deformation behavior of homogenized Al–5Mg–3Zn–1Cu alloy. The results revealed that the flow curves exhibited typical characteristics of DRV/DRX accompanied by the work-hardening, and the existence of three distinct stages of work-hardening, transition, and steady-state in each flow curve. A strain-compensated constitutive model for determining flow stress in this alloy was established with highly acceptable predictability. The dominant deformation mechanism of the alloy is dislocation climbing. Also, dynamic-material-model-based processing maps at various strains were constructed, and the unstable and workable domains were distinguished. Instability generally occurred in high strain rates and low temperatures zone with prevalent instability forms such as cracking and flow localization. The workable domain was 375–450 °C and 0.001–0.1 s−1, in which the microstructure of the deformed alloy was characterized by dynamic recovery and multiple types of dynamic recrystallization. The dynamic precipitates were labeled as T-Mg32(AlZnCu)49 phase. These intermittently distributed precipitates along the grain boundaries were stable in all temperature ranges, while the intragranular precipitates were inhibited at 300 °C. Temperature increment to 400 °C led to a large number of dispersed intragranular precipitates which redissolved into the matrix as temperature exceeded 450 °C.

The microstructure and mechanical properties at different depths of squeeze-cast, solution-treated and aged Al−5.0Mg−3.0Zn−1.0Cu alloy were investigated. For squeeze-cast alloy, from casting surface to interior, the grain size of α(Al) matrix and width of T-Mg32(AlZnCu)49 phase increase significantly, while the volume fraction of T phase decreases. The related mechanical properties including ultimate tensile strength (UTS) and elongation decrease from 243.7 MPa and 2.3% to 217.9 MPa and 1.4%, respectively. After solution treatment at 470 °C for 36 h, T phase is dissolved into matrix, and the grain size increases so that the UTS and elongation from surface to interior are respectively reduced from 387.8 MPa and 18.6% to 348.9 MPa and 13.9%. After further peak-aging at 120 °C for 24 h, numerous G.P. II zone and η′ phase precipitate in matrix. Consequently, UTS values of the surface and interior increase to 449.5 and 421.4 MPa, while elongation values decrease to 12.5% and 8.1%, respectively.

This study investigates the effect of solution treatment (at 470 °C for 0–48 h) on the microstructural evolution, tensile properties, and impact properties of an Al–5.0Mg–3.0Zn–1.0Cu (wt%) alloy prepared by permanent gravity casting. The results show that the as-cast microstructure consists of α-Al dendrites and a network-like pattern of T-Mg32(AlZnCu)49 phases. Most of the T-phases were dissolved within 24 h at 470 °C; and a further prolonging of solution time resulted in a rapid growth of α-Al grains. No transformation from the T-phase to the S-Al2CuMg phase was discovered in this alloy. Both the tensile properties and impact toughness increased quickly, reached a maximum peak value, and decreased gradually as the solution treatment proceeded. The impact toughness is more closely related to the elongation, and the relationship between impact toughness and elongation appears to obey an equation: $${\text{IT}} = 8.43{\text{EL}} - 3.46$$ . After optimal solution treatment at 470 °C for 24 h, this alloy exhibits excellent mechanical properties with the ultimate tensile strength, yield strength, elongation and impact toughness being 431.6 MPa, 270.1 MPa, 19.4% and 154.7 kJ/m2, which are comparable to that of a wrought Al–6.0Mg–0.7Mn alloy (5E06, a 5xxx aluminum alloy). Due to its excellent comprehensive combination of mechanical properties, this cast alloy has high potential for use in components which require medium strength, high ductility and high toughness.

The variation of microstructure and mechanical properties along the cross section of squeeze cast Al-5Mg-3Zn-1Cu-1Si alloy is studied under both squeeze-cast and peak-aged condition (470 °C × 24 h + 125 °C × 24 h). For squeeze-cast alloy, along the depth direction, second dendrite arm space and the percentage of $${\alpha }$$-Al increase significantly, while the volume fraction of T-Mg32(AlZnCu)49 and Mg2Si phase showed a dramatic decrease. The ultimate tensile strength of squeeze-cast alloy slightly decreased from 357.04 MPa for the surface layer to 344.21 MPa for the central layer, yield strength dropped from 296.86 MPa to 241.03 MPa, but the elongation almost tripled from 1.42% to 3.78%. After peak aging, the ultimate tensile strength of surface layer and central layer reached 538.45 MPa and 504.03 MPa, yield strength reached 447.46 MPa and 442.65 MPa, and the elongation reached 5.23% and 3.97% respectively. Meanwhile the difference of ultimate tensile strength and elongation was increased, but that of yield strength reduced after aging treatment. Precipitation strengthening is the main strengthening mechanism while the improvement in ductility is due to the dissolution of T-Mg32(AlZnCu)49 and the morphological change of eutectic Mg2Si.

Drainage is essential for source control of the infection in a pelvic abscess. The purpose of this study was to report 2 cases of endoscopic ultrasound (EUS)-guided drainage of the pelvic abscess and review the literature of different modalities of EUS-guided drainage of pelvic abscess.A 60-year-old male developed a pelvic abscess 1 month after laparoscopic complete tumor resection. An abdominal CT showed a mass shadow (about 7.1 cm × 5.1 cm) in the right pelvic region. Another case was an 85-year-old male who developed a pelvic abscess 3 days after recurrent tumor resection of multiple organs. The CT showed pelvic effusion and gas accumulation (approximately 6.5 cm × 4.2 cm), and the intestinal tube above the small intestinal anastomosis was dilated with effusion. A 19G-A puncture needle was used to puncture the abscess. An 8-mm cylindrical balloon was inserted, followed by a 10 Fr-3 cm double pigtail stent and an 8.5 Fr drainage tube. After EUS-guided drainage of pelvic abscess, the symptoms disappeared without recurrence.EUS-guided drainage is an effective and safe method for treating pelvic abscesses as long as the drainage modality is appropriately selected based on the etiology, size, and mucus viscosity of the abscess.Bei einem Beckenabszess ist eine Drainage zur Eindämmung der Infektionsquelle unabdingbar. In dieser Studie berichten wir über 2 Fälle einer endosonografisch gezielten Drainage eines Beckenabszesses und geben eine Literaturübersicht über die verschiedenen Modalitäten einer endosonografisch gezielten Drainage von Beckenabszessen.Ein 60-jähriger Mann entwickelte 1 Monat nach einer vollständigen laparoskopischen Tumorresektion einen Beckenabszess. Das CT zeigte einen Massenschatten (etwa 7,1 cm × 5,1 cm) im rechten Becken. In einem weiteren Fall entwickelte ein 85-jähriger Mann 3 Tage nach einer wiederholten Tumorresektion mehrerer Organe einen Beckenabszess. Das CT zeigte einen Erguss und eine Gasansammlung (ca. 6,5 cm × 4,2 cm) im Becken, und das Darmrohr oberhalb der Dünndarmanastomose war durch einen Erguss erweitert. Zur Punktion des Abszesses wurde eine 19G-A-Punktionsnadel verwendet. Es wurde ein zylindrischer 8-mm-Ballon eingeführt, gefolgt von einem 10Fr-3-cm-Doppel-Pigtail-Stent und einem 8,5Fr-Drainageschlauch. Nach der endosonografisch gezielten Drainage des Beckenabszesses verschwanden die Symptome, es trat kein Rezidiv auf.Die endosonografisch gezielte Drainage ist eine wirksame und sichere Methode zur Behandlung von Beckenabszessen, solange die Drainagemethode entsprechend der Ätiologie, Größe und Schleimviskosität des Abszesses passend ausgewählt wird.

Background Multipotent mesenchymal stromal cell (MSC) therapy has been widely recognized as a feasible strategy for regenerating injured myocardial tissue. However, little is known about the efficacy of intravenous injection of allogeneic umbilical cord (UC) MSCs in preclinical models of porcine myocardial infarction. Methods Different dosages of allogeneic UC-MSCs or the vehicle [phosphate-buffered saline (PBS)] were delivered intravenously into an acute myocardial infarction (AMI) porcine model twice after coronary ligation. Echocardiography was performed to examine the cardiac function and single photon emission computed tomography (SPECT) and positron emission tomography (PET)/computed tomography (CT) was performed to detect cardiac perfusion and nonviable myocardium. At the end of the experiment, 2,3,5-triphenyl-tetrazolium chloride (TTC) staining and Masson T staining were performed to determine the infarct area. The protein and gene expression levels associated with cardiac function, inflammation, and angiogenesis were examined by Western blot and real time polymerase chain reaction (PCR). In vivo trafficking of intravenous injection of allogeneic UC-MSCs enhanced green fluorescent protein (eGFP) was detected by real time PCR and immunofluorescence. Results After systemic delivery, allogeneic UC-MSCs were largely distributed in the lungs and some in the infracted myocardium. At week 8 following AMI, echocardiography demonstrated significantly improved fractional shortening in the high-dose (1.5 × 106 cells/kg) group. SPECT-PET/CT showed that UC-MSC treatment in both high and low doses markedly ameliorated the left ventricle (LV) infarct area but did not significantly improve the myocardial perfusion defect. LV remodeling was inhibited by UC-MSC therapy, as reflected by a marked reduction in rthe fibrosis area at basal, middle, and apical levels and reduced extracellular matrix deposition in the total myocardial area. Inflammatory biomarkers (tumor necrosis factor alpha and interleukin-6) were reduced and pro-angiogenesis factors (vascular endothelial growth factor and platelet/endothelial cell adhesion molecule 1) were augmented in the myocardial infarct and border area. High-dose UC-MSCs increased the connexin 43 (Cx43) (myocardium preservation) expression in remote area of the LV myocardium after AMI. Conclusions Intravenous injection of UC-MSCs is a feasible and effective way to preserve LV function and ameliorate myocardial remodeling in porcine AMI. The cardioprotective effects of UC-MSCs were attributed to paracrine factors that appear to augment angiogenesis, limit inflammation, and preserve Cx43 gap junction. Electronic supplementary material The online version of this article (10.1186/s13287-018-0888-z) contains supplementary material, which is available to authorized users.

Evidence-based studies are increasingly being focused on evaluating the efficacy and safety of adalimumab (ADA) for moderately to severely active ulcerative colitis (UC). However, the dosage pattern of ADA for UC management is still not clear. A meta-analysis was conducted to evaluate the efficacy and safety of different ADA dosage regimens for moderately to severely active UC. The Medline, EMBASE, ISI Web of Knowledge, and Cochrane databases were searched from their inception to January 2015. Randomized controlled trials (RCTs) comparing ADA with placebo were eligible for initial inclusion. The efficacy and side effects were evaluated for ADA 160/80 (ADA 160/80 mg at weeks 0/2 and then 40 mg at weeks 4 and 6), and ADA 80/40 (ADA 80/40 mg at weeks 0/2 and then 40 mg at weeks 4 and 6) induction therapy, with ADA 40 mg every other week (EOW) for maintenance therapy of 52 weeks. The pooled risk ratio (RR) and its 95 % confidence interval (CI) were calculated. Three RCTs were included. All of the studies were considered to have a low risk of bias. ADA 160/80 was more effective than placebo for induction of clinical remission (RR 1.62, 95 % CI 1.15–2.29), clinical response (RR 1.37, 95 % CI 1.19–1.59), mucosal healing (RR 1.27, 95 % CI 1.08–1.50), and inflammatory bowel disease questionnaire (IBDQ) response (RR 1.22, 95 % CI 1.05–1.43) and did not increase adverse events (RR 1.10, 95 % CI 0.95–1.27). Compared with placebo, ADA 80/40 did not show significant differences for induction of clinical remission and clinical response and did not increase adverse events. ADA 40 mg EOW was superior to placebo in maintaining clinical remission (RR 2.38, 95 % CI 1.57–3.59), clinical response (RR 1.69, 95 % CI 1.29–2.21), mucosal healing (RR 1.69, 95 % CI 1.26–2.28), and IBDQ response (RR 1.73, 95 % CI 1.28–2.34). Compared with placebo, ADA 40 mg EOW increased adverse events (RR 1.28, 95 % CI 1.06–1.54). ADA 160/80 was a safe and effective treatment for induction management of moderately to severely active UC, but the benefits of ADA 80/40 application were limited. ADA 40 mg EOW was effective for maintenance management of UC. Additional well designed RCTs are needed to confirm these results.

This study investigates the relationship between aging temperature on the precipitation behavior and mechanical properties of a gravity cast Al-5.0Mg-3.0Zn-1.0Cu (wt%) alloy. After solution treatment at 470 °C for 24 h, alloys were aged at 120, 150 and 175 °C. Upon analyzing the samples, the alloys displayed different age hardening behaviors due to the variations in aging temperature. An increase in aging temperature not only reduced the peak aging time significantly, but also changed the distribution of precipitates. Numerous GPII zones and T′ precipitates (precursors of T-Mg32(AlZn)49) were homogeneously distributed within matrix at a higher aging temperature and the volume fraction of T′ precipitates increased. Tensile test results for peak-aged samples determined that both yield strength (YS) and ultimate tensile strength (UTS) increased, while elongation (EL) decreased with increasing temperature. The increase in the YS can be attributed to the higher volume fraction of T′ precipitates caused by the higher aging temperature. Moreover, the impact toughness decreased (due to a continuous decrease in EL) as the aging temperature increased. By adjusting aging temperature from 120 to 175 °C, YS increased from 377 to 451 MPa, while EL decreased from 13.8% to 5.2%. After peak aging treatment at 150 °C, the alloy appears to possess optimal mechanical properties with YS, UTS, EL and toughness being 441 MPa, 496 MPa, 9.6%, and 8.1 J/cm2, respectively. These finding suggest that there are many potential advantageous applications for this alloy within automobile components requiring high strength and toughness.

The aim of this study was to develop and validate the large intestine dampness-heat syndrome questionnaire (LIDHSQ) for patients with ulcerative colitis (UC). The domains and items of the LIDHSQ were developed according to standard procedures, namely, construct definition, item generation, language testing, content validity, pilot study, and validation study. At first, a total of 20 items in 3 domains were generated based on literature review and expert consultation. After the item selection, the LIDHSQ contains 11 items in three domains: disease-related domain (diarrhoea, abdominal pain, bloody purulent stool, and mucus stool), heat domain (fever, dry mouth, red tongue, yellow fur, and anal burning), and dampness domain (greasy fur and defecation disorder). The Cronbach's alphas of all domains were greater than 0.6. All of the intraclass correlation coefficients were greater than 0.8. The LIDHSQ and domain scores of the patients with LIDHS were higher than those of the patients with other syndromes (P < 0.001). The area under the receiver operating characteristic curve of the LIDHSQ was 0.900, with a 95% confidence interval of 0.872–0.928. When the cut-off value of the LIDHSQ was ≥ 7, the sensitivity and specificity were 0.867 and 0.854, respectively. The LIDHSQ is valid and reliable for measuring LIDHS in UC patients with good diagnostic efficacy. We recommend the use of the LIDHSQ in Chinese UC patients.

Girolami and coworkers have proposed measures of quantum correlations and weaving [Girolami et al., Phys. Rev. Lett. 119, 140505 (2017)]. This work derives the analytic time-evolution of such measures and weaving for two kinds of initial states in three qubits under an amplitude-damping and a dephasing noisy environment. It is shown that the 2-partite correlation is forever frozen, which is dependent on an initial state and the property of noise.

Background Previously designed intra-thoracic paraaortic counterpulsation device has limited stroke volume and may depress the lung to cause complications. The purpose of this study was to evaluate the hemodynamic effects of an extra-thoracic paraaortic counterpulsation device (ETPACD) in comparison to intraaortic balloon pump (IABP) in an animal model with acute heart failure. Methods The acute heart failure model was successfully induced by snaring branch of anterior descending coronary artery in sheep (weighting, 38-50 kg, n = 8). The ETPACD is a single port, 65-ml stroke volume blood chamber designed to be connected to descending aorta through a valveless graft and placed extra-thorax. In comparison, a standard clinical 40-ml IABP was placed in the descending aorta. The hemodynamic indices of both devices were recorded during counterpulsation assistance. Two of the sheep were allowed to survive for 1 week to examine the prolonged effect. Results Both ETPACD and IABP increased cardiac output with higher effect of ETPACD (13.52 % vs. 8.19 % in IABP, P 0.05). The ETPACD increased left carotid artery flow more significantly the IABP (18.00 % vs. 9.19 % , P