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The microstructure evolution and mechanical properties of the as-deposited γ-TiAl-based alloy specimen fabricated via laser melting deposition and as-annealed specimens at different temperatures were investigated. The results show that the microstructure of as-deposited specimen is composed of fine α2(Ti3Al)+γ lamellae. With the increase of annealing temperature, the bulk γm (TiAl) phase gradually changes from single γ phase to γ phase + acicular α2 phase, finally small γ phase + lamellar α2+γ phase. Compared with the mechanical properties of as-deposited γ-TiAl alloy (tensile strength 469 MPa, elongation 1.1%), after annealing at 1260 °C for 30 min followed by furnace cooling (FC), the room-temperature tensile strength of the specimen is 543.4 MPa and the elongation is 3.7%, which are obviously improved.

Objective: Percutaneous transluminal balloon angioplasty (PTA) is recommended as the first choice to treat stenosis of Brescia-Cimino arteriovenous fistulas (B-C AVFs). The ability to predict which B-C AVFs are at risk for recurrent stenosis post-PTA would allow closer monitoring of patients, and possibly result in surgical intervention rather than repeat PTA. The purpose of this study was to identify predictive factors of primary patency after PTA in B-C AVFs. Methods: Patients diagnosed with B-C AVF primary stenosis and treated by PTA between November 2013 and March 2018 were included in the study. Patient and stenotic lesion characteristics and PTA procedure factors were included in the analysis. The Kaplan–Meier method was used to analyze the primary patency rate. Cox proportional hazard regression analysis was used to identify factors predictive of decreased primary patency. Results: 74 patients (35 males, 39 females) with a mean age of 61.68 ± 11.44 years (range, 36–84 years) were included in the study. The mean B-C AVF age was 16.34 ± 12.93 months (range, 2–84 months), and the median primary patency time was 7.79 ± 0.48 months. Cox proportional hazard regression analysis revealed stenosis location at the inflow artery [hazard ratio (HR)=3.83, 95% confidence interval (CI): 1.46–10.09] or anastomosis (HR = 1.90, 95% CI: 1.09–3.32), dilation >2 times during PTA (HR = 2.30, 95% CI: 1.22–4.34), and residual stenosis >30% (HR = 2.42, 95% CI: 1.26–4.63) were significantly associated with decreased patency. Conclusion: In conclusion, the primary patency rate of PTA for B-C AVF dysfunction is reduced by dilation >2 times, residual stenosis >30%, and stenosis located at the inflow artery or anastomosis. These results may help in tailoring surveillance programs, multiple PTA, or a proximal re-anastomosis surgery in patients with AVF dysfunction. Advances in knowledge: A number of studies have been conducted to examine the predictors of primary patency after PTA, however, no definitive conclusions have been reached. Our study revealed that stenosis location at the inflow artery or anastomosis, dilation >2 times during PTA, and residual stenosis >30% were the predictors of primary patency after PTA, which may help in tailoring surveillance programs, multiple PTA, or a proximal re-anastomosis surgery in patients with arteriovenous fistulas dysfunction.

Orychophragmus violaceus (L.) O.E. Schulz (Chinese violet cress) belongs to the Brassicaceae family and is widely distributed in China as a garden plant. In April 2016, severe leaf spot disease was observed on cultivated O. violaceus in Xuanwu Lake Park, Nanjing, Jiangsu province, China. The initial symptoms were small brown spots (1 to 2 mm in diameter) on the leaves. The spots enlarged to 10 to 15 mm in diameter, light brown to black, sometimes comprising concentric rings surrounded by a yellow halo. Severely infected leaves became black to gray and dry. More than 10 symptomatic leaves were randomly collected, and tissues (2 mm) were incubated on moistened filter papers at 25°C for 1 day. Three pure cultures (YZU 161008, YZU 161009, and YZU 161010) were obtained by single-spore isolation and deposited in the Culture Collection of Yangtze University. Each isolate was cultured on potato dextrose agar (PDA) at 25°C in darkness. After 7 days, the upper sides of colonies were cottony and white, and the reverse sides were buff, 37 to 38 mm in diameter, with irregular margins. For morphological observation, the fungus was cultured on potato carrot agar at 22°C with a light/dark period of 8 h/16 h according to the method of Simmons (2007). After 7 days, conidiophores arose directly from the agar surface. Conidia were 10 to 42 × 8 to 19 μm in size, short- to long-ovoid, smooth-walled, medium tawny in color, middle and basal parts of several cells were markedly swollen, beakless, with one to five transverse septa. They formed short chains of one to four conidia. Numerous microchlamydospores were observed. Individual microchlamydospores were 6 to 13 × 8 to 19 μm in size, irregular in shape, multicellular, cells swollen, thick-walled, and heavily pigmented. Branching groups were around 15 to 136 μm in length. The characteristics in culture and conidial morphology were identical to Alternaria japonica (Simmons 2007). Genomic DNA was extracted from fresh mycelia of two selected isolates (YZU 161009 and YZU 161010) according to the method of Cenis (1992). Three gene regions including internal transcribed spacer rDNA regions (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and partial translation elongation factor 1 alpha (TEF1) were amplified using the primer pairs ITS4/ITS5 (White et al. 1990), gpd1/gpd2 (Berbee et al. 1999), and EF1-728F/EF1-986R (Carbone and Kohn 1999), respectively. PCR amplifications were conducted using the following conditions: an initial denaturation at 94°C for 2 min; 30 amplification cycles of 98°C for 5 s, 50°C (ITS and TEF1)/57°C (GAPDH) for 15 s, and 72°C for 5 s; and a final extension phase at 72°C for 10 min. The DNA sequences of two isolates were deposited in the GenBank nucleotide database with accession numbers MK940391 (ITS, 597 bp), MK940389 (GAPDH, 611 bp), and MK940387 (TEF1, 367 bp) for YZU 161009 and MK940392 (ITS, 599 bp), MK940390 (GAPDH, 596 bp), and MK940388 (TEF1, 283 bp) for YZU 161010. All the sequences were compared using the BLASTn tool, and the results showed that they were 100% identical to A. japonica (CBS 118390) and A. nepalensis (CBS 118700). Simmons (2007) reported microchlamydospore production by A. japonica and not A. nepalensis, which supports the diagnosis of these isolates as A. japonica. Pathogenicity tests were carried out with YZU 161009 and YZU 161010 using two methods on 2-month-old healthy plants (six plants for each method). A 20-μl conidial suspension (10⁵ conidia/ml) was applied on five to six points per leaf with sterilized ddH₂O used as the negative control. Mycelia plugs grown on PDA (2 to 3 mm in diameter) were also applied to one point per leaf, with pure PDA plugs as the negative control. After 7 days at 25°C in a greenhouse, brown necrotic lesions developed on leaves for each inoculated with conidial suspension (1 to 5 mm in diameter) and mycelia plugs (10 to 20 mm in diameter). Control plants were symptomless. The fungus reisolated from diseased tissues was confirmed as A. japonica based on the morphology of conidia and microchlamydospores, thus fulfilling Koch’s postulates. To the best of our knowledge, this is the first report of A. japonica causing leaf spot on O. violaceus in China. The identification of the pathogen is important for improving management strategies and control of this disease.

In order to identify the critical properties and failure criteria of in-situ silt under vehicle or wave loading, anisotropically consolidated silt under undrained cyclic principal stress rotation was studied with hollow cylinder dynamic tests. The results show that for the slightly anisotropically consolidated samples with consolidation ratios no larger than 1.5, the structure collapses and the deviator strain and pore pressure increase sharply to fail after collapse. For the highly anisotropically consolidated samples with consolidation ratios larger than 1.5, the strain increases steadily to high values, which shows characteristics of ductile failure. 4% is suggested to be the threshold value of deviator stain to determine the occurrence of collapse. The normalized relationship between pore pressure and deviator strain can be correlated by a power function for all the anisotropically consolidated samples. Based on it, for the highly anisotropically consolidated samples, the appearance of inflection point on the power function curve is suggested to sign the failure. It can be predicted through the convex pore pressure at this point, whose ratio to the ultimate pore pressure is around linear with the consolidation ratio in spite of the dynamic shear stress level. And the corresponding deviator strain is between 3% and 6%. The strain failure criterion can also be adopted, but the limited value of stain should be determined according to engineering practice. As for the slightly anisotropically consolidated samples, the turning points appear after collapse. So, the failure is suggested to be defined with the occurrence of collapse and the collapse pore pressure can be predicted with the ultimate pore pressure and consolidation ratio.

In order to consider the influence of water pressure on cohesive soil slope with groundwater, the local and global water pressure methods are proposed. The equivalence and applicability of the two methods based on the simplified Bishop’s method are analyzed. The local water pressure method considers the water pressures on boundaries as components and the global water pressure method considers the water pressures as a resultant force. The physical analysis and numerical verification showed these two methods are completely equivalent. While the global water pressure method is more convenient in hydrostatic condition, the local water pressure method is prior in seepage condition. It is also pointed out that there are significant defects in some regular expressions of simplified Bishop’s method. Because they neglect the moment generated by water pressure on the top boundary of slope or wrongly evaluate of the hydrodynamic failure states with hydrostatic stress parameters.

To study the therapeutic effects of posterolateral depression fractures of the tibial plateau through a modified anterolateral approach.From February 2011 to January 2012,13 patients with posterolateral depression fractures of the tibial plateau were treated through a modified anterolateral approach. There were 8 males and 5 females, ranging in age from 28 to 59 years old (49.2 years old on average). Data from patients were collected retrospectively as follows: X-ray, time of fracture healing and the complications of fracture healing. The patients were evaluated both clinically and radiologically according to the Rasmussen score system.All the patients were followed up, and the duration ranged from 6 to 18 months (mean 13.7 months). All the patients got bony union. The average radiographic bony union time was 15.1 weeks (ranged, 11 to 17 weeks). No case of secondary articular depression was found. No complications such as malunion or joint stiffness were found. But 1 patient had superficial infection and 1 patient had common peroneal nerve injury. According to the Rasmussen score system,the mean radiological score was 16.50 ± 0.67 (ranged, 13 to 18), and the mean functional score was 25.20 ± 2.21 (ranged, 13 to 30). The mean range of knee motion was (125.3 ± 9.3)° (ranged, 0° to 135°).Treatment of depression fractures of posterolateral tibial plateau with a modified anterolateral approach is a safe method with effective exposure, due to its stable fixation and relatively good outcome with minimal soft-tissue complications. It is regarded as an ideal procedure for depression fractures of posterolateral tibial plateau.

To evaluate the effects of cervical vertebrae degeneration on traumatic cervical cord injury.From January 2009 to December 2010, 24 patients with cervical cord injury without obvious fractures and dislocations were treated with operation, and their data were retrospectively analyzed. Among them, 16 males and 8 females, aged from 46 to 70 years old with an average of 59.1 years. Patients were divided into light degeneration group (6 cases), moderate degeneration group (10 cases) and severe degeneration group (8 cases), according to the preoperative degenerative degree of cervical vertebrae. Preoperative neurological dysfunction and postoperative neurological recovery were compared according to the JOA scores of Japanese Orthopaedic Society; quality of life were evaluated according to SF-36 scale (36-item Short Form Health Survey, SF-36).All patients were followed up from 4 to 16 months with an average of 12 months. The JOA score of light, moderate, severe degeneration group were 12.1 +/- 1.5, 10.3 +/- 1.8, 7.3 +/- 1.0, respectively; and were respectively increased to 16.3 +/- 1.0, 15.3 +/- 1.4, 13.0 +/- 2.3 at the 3 months after operation. Postoperative JOA score showed the improvement rate of mid-long-term neurological level was light degeneration group (89.8%)moderate degeneration group (76.6%)severe degeneration group (58.8%). The results of preoperative SF-36 scale showed light degeneration groupmoderate degeneration groupsevere degeneration group; there was significant difference in comparison of two groups (P0.05 ).Cervical degeneration is an important pathologic basis and risk factor in traumatic cervical cord injury, and the degenerative degree will directly influence the injury degree and prognosis of neurological function, the clinical relationship between them should be sufficiently paid attention to.

To evaluate the efficacy and the feasibility of bending rod reduction in situ technique in treating low lumbar burst fracture.From March 2007 to June 2009, 21 patients with low lumbar burst fracture were retrospectively analyzed, 11 cases were in L3,6 in L4 and 4 in L5. There were 16 males and 5 females, ranging in age from 25 to 59 year with an average of 37.9 years. According to ASIA classification, nerve function was level A in 2 cases, level B in 2, level C in 10, level D in 4 and level E in 3. Pedicle screws were implanted and bending rod reduction in situ technique was applied through posterior approach. Radiographic and neurological scores were compared before and after operation.All patients were followed up from 12 to 39 months with an average of 16.5 months. Radiographic examinations demonstrated that anterior height of fractured vertebral body was from 57.9% preoperatively to 94.1% postoperatively (P0.01 ); sagittal index was from 29.1 preoperatively to 0.240 postoperatively (P0.01). Spinal canal occupation ratio was from 49.6% preoperatively to 13.4% postoperatively (P0.01). Nerve function was level A in 2 cases,level B in 0, level C in 0, level D in 4 and level E in 15.Bending rod in situ technique could achieve 3-column reduction in 3-dimentionally at the same time, and reconstruct the stability of low lumbar.

To explore the feasibility, safety, and cosmetic efficacy of endoscope-assisted thyroidectomy (EAT) by chest approach.Fifty-one patients with single benign thyroid noduleor = 4.0 cm in diameter, and without history of neck surgery or irradiation, 8 males and 43 females, aged 33.9 (18-64), underwent endoscope-assisted thyroidectomy by chest approach: a skin incision with the length of 4 cm was made in the chest, an endoscope was inserted, and subtotal or total thyroidectomy with the technique similar to that in conventional surgery was performed with naked eyes.Subtotal thyroidectomy was performed in 49 patients, and total excision of unilateral thyroid lobe plus isthmus lobectomy and contralateral partial lobectomy was performed on the other 2 patients. No patient was transferred to traditional surgery. Only one case showed palsy of recurrent nerve. Most patients expressed with the cosmetic results.EAT is a feasible and safe procedure with rather good cosmetic