In this paper, the effect of continuous and pulsed current in the gas tungsten arc welding (GTAW) on the various properties of an AISI 316L stainless steel joints was investigated. 316L austenitic ...stainless steel sheets with a thickness of 10 mm were used together with ER309L filler. The sheets were welded together by the GTAW technique in two modes of continuous and pulsed currents. Microstructural characterization and phase equilibria were done using optical microscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) equipped with electron backscatter diffraction (EBSD) detector, techniques. Charpy impact, uniaxial tensile, and microhardness tests were used to investigate the effect of the type of the welding current on mechanical properties of the joints. The fracture surfaces were evaluated by FE-SEM after tensile and Charpy impact tests. Results showed that the weld metal (WM) microstructure is austenitic-ferritic (AF). It was also consisted of columnar and coaxial structures, in a way that varying the welding current from continuous to the pulsed mode changed the morphology of the grains from elongated columnar to a fine coaxial morphology. In addition, such a change in the welding current reduced the size of the grains in the WM, and the width of the unmixed zone (UMZ) as well. XRD analysis showed that the predominant phase and the preferred crystal plane of the WM are austenite, and (111), respectively. Both joints were broken from the base metal (BM) during the tensile test. Also, the above change of the welding current mode increased hardness and fracture toughness of the WM. Finally, fractography of the joints indicated that both joints experienced a completely ductile fracture.
Background
Maximum urinary flow rate (Qmax) is usually increased after holmium laser enucleation of the prostate (HoLEP). However, improvements vary between patients and results regarding potential ...predictors of Qmax after HoLEP are inconsistent. Thus, we investigated pre‐operative variables including second to fourth digit ratio (digit ratio) and pulmonary function test (PFT) findings as potential predictors of Qmax after HoLEP.
Methods
One hundred and ninety‐five consecutive patients with benign prostatic hyperplasia (BPH) who underwent HoLEP were enrolled. Before HoLEP, PFTs were performed and lengths of second and fourth digits of right hands were measured by a single investigator using a digital vernier caliper. To identify independent predictors of Qmax after HoLEP, univariate and multivariate analyses were performed using linear regression models.
Results
Mean age and total prostate volume for all 195 study subjects were 69.4 years and 63.3 mL respectively. Mean pre‐operative and post‐operative Qmax values were 8.7 and 26.2 mL/sec respectively. Univariate analysis showed age (r = −0.181, p = 0.014), digit ratio (r = 0.213, p = 0.004), lung function (forced vital capacity (FVC): r = 0.218, p = 0.005; forced expiratory volume in 1 sec (FEV1): r = 0.166, p = 0.034), pre‐operative Qmax (r = 0.264, p = 0.000), pre‐operative voided volume (VV) (r = 0.158, p = 0.033), and post‐operative VV (r = 0.311, p = 0.000) were associated with post‐operative Qmax, whereas multivariate analysis showed that digit ratio (β = 0.285, p = 0.001), FVC (β = 0.340, p = 0.039), and post‐operative VV (β = 0.301, p = 0.000) independently predicted post‐operative Qmax.
Conclusions
The independent predictors of Qmax after HoLEP were digit ratio and lung function (FVC) as well as post‐operative VV. This means that the higher a man's digit ratio and lung function (FVC), the higher his Qmax after HoLEP.
Despite a number of previous nonequilibrium molecular dynamics (MD) studies into plasticity in face-centered-cubic metals, and phase transitions in body-centered-cubic (bcc) metals, the plastic ...response to rapid compression of bcc metals remains largely unexplored. Key questions remain as to the relative importance of dislocation motion and twinning in shear stress release and consequent strength. We present here large scale MD simulations of shock compressed bcc metal, using an extended Finnis-Sinclair potential for tantalum, and demonstrate the presence of significant deformation twinning for pressures above the Hugoniot elastic limit for shock waves propagating along the 001 direction. The twinned variants are separately identified by a per atom order parameter, allowing the strain and stress states of the rotated material to be studied. The atomic motion during twinning, and thus its mechanism, for this potential, is identified by use of a three-dimensional pair-correlation function.
Oral mucosa provides the first line of defense against a diverse array of environmental and microbial irritants by forming the barrier of epithelial cells interconnected by multiprotein tight ...junctions (TJ), adherens junctions, desmosomes, and gap junction complexes. Grainyhead-like 2 (GRHL2), an epithelial-specific transcription factor, may play a role in the formation of the mucosal epithelial barrier, as it regulates the expression of the junction proteins. The current study investigated the role of GRHL2 in the Porphyromonas gingivalis (Pg)–induced impairment of epithelial barrier functions. Exposure of human oral keratinocytes (HOK-16B and OKF6 cells) to Pg or Pg-derived lipopolysaccharides (Pg LPSs) led to rapid loss of endogenous GRHL2 and the junction proteins (e.g., zonula occludens, E-cadherin, claudins, and occludin). GRHL2 directly regulated the expression levels of the junction proteins and the epithelial permeability for small molecules (e.g., dextrans and Pg bacteria). To explore the functional role of GRHL2 in oral mucosal barrier, we used a Grhl2 conditional knockout (KO) mouse model, which allows for epithelial tissue-specific Grhl2 KO in an inducible manner. Grhl2 KO impaired the expression of the junction proteins at the junctional epithelium and increased the alveolar bone loss in the ligature-induced periodontitis model. Fluorescence in situ hybridization revealed increased epithelial penetration of oral bacteria in Grhl2 KO mice compared with the wild-type mice. Also, blood loadings of oral bacteria (e.g., Bacteroides, Bacillus, Firmicutes, β-proteobacteria, and Spirochetes) were significantly elevated in Grhl2 KO mice compared to the wild-type littermates. These data indicate that Pg bacteria may enhance paracellular penetration through oral mucosa in part by targeting the expression of GRHL2 in the oral epithelial cells, which then impairs the epithelial barrier by inhibition of junction protein expression, resulting in increased alveolar tissue destruction and systemic bacteremia.
To propose a new and practical MRI grading method for cervical neural foraminal stenosis and to evaluate its reproducibility.
We evaluated 50 patients (37 males and 13 females, mean age 49 years) who ...visited our institution and underwent oblique sagittal MRI of the cervical spine. A total of 300 foramina and corresponding nerve roots in 50 patients were qualitatively analysed from C4-5 to C6-7. We assessed the grade of cervical foraminal stenosis at the maximal narrowing point according to the new grading system based on T2 weighted oblique sagittal images. The incidence of each of the neural foraminal stenosis grades according to the cervical level was analysed by χ(2) tests. Intra- and interobserver agreements between two radiologists were analysed using kappa statistics. Kappa value interpretations were poor (κ<0.1), slight (0.1≤κ≤0.2), fair (0.2<κ≤0.4), moderate (0.4<κ≤0.6), substantial (0.6<κ≤0.8) and almost perfect (0.8<κ≤1.0).
Significant stenoses (Grades 2 and 3) were rarely found at the C4-5 level. The incidence of Grade 3 at the C5-6 level was higher than that at other levels, a difference that was statistically significant. The overall intra-observer agreement according to the cervical level was almost perfect. The agreement at each level was almost perfect, except for only substantial agreement at the right C6-7 by Reader 2. No statistically significant differences were seen according to the cervical level. Overall kappa values of interobserver agreement according to the cervical level were almost perfect. In addition, the agreement of each level was almost perfect. Overall intra- and interobserver agreement for the presence of foraminal stenosis (Grade 0 vs Grades 1, 2 and 3) and for significant stenosis (Grades 0 and 1 vs Grades 2 and 3) showed similar results and were almost perfect. However, only substantial agreement was seen in the right C6-7.
A new grading system for cervical foraminal stenosis based on oblique sagittal MRI provides reliable assessment and good reproducibility. This new grading system is a useful and easy method for the objective evaluation of cervical neural foraminal stenosis by radiologists and clinicians.
The use of the new grading system for cervical foraminal stenosis based on oblique sagittal MRI can be a useful method for evaluating cervical neural foraminal stenosis.
Although total knee arthroplasty is a successful and cost-effective procedure, patient dissatisfaction remains as high as 50%. Postoperative residual knee pain after total knee arthroplasty, with or ...without crepitation, is a major factor that contributes to patient dissatisfaction. The most common location for residual pain after total knee arthroplasty is anteriorly. Because residual pain has been associated with an un-resurfaced patella, this review includes only registry data and total knee arthroplasty with patella replacement. Some suggest that the pathogenesis of residual knee pain may be related to mechanical stimuli that activate free nerve endings around the patellofemoral joint. Various etiologies have been implicated in residual pain, including (1) low-grade infection, (2) midflexion instability, and (3) component malalignment with patellar maltracking. Less common causes include (4) crepitation and patellar clunk syndrome; (5) patellofemoral symptoms, including overstuffing and avascular necrosis of the patella; (6) early aseptic loosening; (7) hypersensitivity to metal or cement; (8) complex regional pain syndrome; and (9) pseudoaneurysm. Because all of these conditions can lead to residual pain, identifying the etiology can be a difficult diagnostic challenge. Often, patients with persistent pain and normal findings on radiographs and laboratory workup may benefit from a diagnostic injection or further imaging. However, up to 10% to 15% of patients with residual pain may have unexplained pain. This literature review summarizes the findings on the causes of residual pain and presents a diagnostic algorithm to facilitate an accurate diagnosis for residual pain after total knee arthroplasty.
Abstract Background The efficacy of neoadjuvant chemotherapy before surgery (NCS) has not been well-established in FIGO stage IB1 to IIA cervical cancer when compared with primary surgical treatment ...(PST). Thus, we performed a meta-analysis to determine the efficacy of NCS in patients with FIGO stage IB1 to IIA cervical cancer when compared with PST. Methods We searched Pubmed, Embase and the Cochrane Library between January 1987 and September 2010. Since there was a relative lack of relevant randomized controlled trials (RCTs), we included 5 RCTs and 4 observational studies involving 1784 patients among 523 potentially relevant studies. Results NCS was related with lower rates of large tumor size (≥4 cm) (ORs, 0.22 and 0.10; 95% CI, 0.13–0.39 and 0.02–0.37) and lymph node metastasis (ORs, 0.61 and 0.38; 95% CI, 0.37–0.99 and 0.20–0.73) than PST in all studies and RCTs. Furthermore, NCS reduced the need of adjuvant radiotherapy (RT) in all studies (OR, 0.57; 95% CI, 0.33–0.98), and distant metastasis in all studies and RCTs (ORs, 0.61 and 0.61; 95% CI, 0.42–0.89 and 0.38–0.97). However, overall and loco-regional recurrences and progression-free survival were not different between the 2 treatments. On the other hand, NCS was associated with poorer overall survival in observational studies when compared with PST (HR, 1.68; 95% CI, 1.12–2.53). Conclusions Although NCS reduced the need of adjuvant RT by decreasing tumor size and lymph node metastasis, and distant metastasis, it failed to improve survival when compared with PST in patients with FIGO stage IB1 to IIA cervical cancer.
We present measurements of the relative abundances of cosmic-ray nuclei in the energy range of 500-3980 GeV/nucleon from the second flight of the Cosmic Ray Energetics And Mass balloon-borne ...experiment. Particle energy was determined using a sampling tungsten/scintillating-fiber calorimeter, while particle charge was identified precisely with a dual-layer silicon charge detector installed for this flight. The resulting element ratios C/O, N/O, Ne/O, Mg/O, Si/O, and Fe/O at the top of atmosphere are 0.919 {+-} 0.123{sup stat} {+-} 0.030{sup syst}, 0.076 {+-} 0.019{sup stat} {+-} 0.013{sup syst}, 0.115 {+-} 0.031{sup stat} {+-} 0.004{sup syst}, 0.153 {+-} 0.039{sup stat} {+-} 0.005{sup syst}, 0.180 {+-} 0.045{sup stat} {+-} 0.006{sup syst}, and 0.139 {+-} 0.043{sup stat} {+-} 0.005{sup syst}, respectively, which agree with measurements at lower energies. The source abundance of N/O is found to be 0.054 {+-} 0.013{sup stat} {+-} 0.009{sup syst+0.010esc} {sub -0.017}. The cosmic-ray source abundances are compared to local Galactic (LG) abundances as a function of first ionization potential and as a function of condensation temperature. At high energies the trend that the cosmic-ray source abundances at large ionization potential or low condensation temperature are suppressed compared to their LG abundances continues. Therefore, the injection mechanism must be the same at TeV/nucleon energies as at the lower energies measured by HEAO-3, CRN, and TRACER. Furthermore, the cosmic-ray source abundances are compared to a mixture of 80% solar system abundances and 20% massive stellar outflow (MSO) as a function of atomic mass. The good agreement with TIGER measurements at lower energies confirms the existence of a substantial fraction of MSO material required in the {approx}TeV per nucleon region.
Defective biosynthesis of the phospholipid PI(3,5)P
underlies neurological disorders characterized by cytoplasmic accumulation of large lysosome-derived vacuoles. To identify novel genetic causes of ...lysosomal vacuolization, we developed an assay for enlargement of the lysosome compartment that is amenable to cell sorting and pooled screens. We first demonstrated that the enlarged vacuoles that accumulate in fibroblasts lacking FIG4, a PI(3,5)P
biosynthetic factor, have a hyperacidic pH compared to normal cells'. We then carried out a genome-wide knockout screen in human HAP1 cells for accumulation of acidic vesicles by FACS sorting. A pilot screen captured fifteen genes, including VAC14, a previously identified cause of endolysosomal vacuolization. Three genes not previously associated with lysosome dysfunction were selected to validate the screen: C10orf35, LRRC8A, and MARCH7. We analyzed two clonal knockout cell lines for each gene. All of the knockout lines contained enlarged acidic vesicles that were positive for LAMP2, confirming their endolysosomal origin. This assay will be useful in the future for functional evaluation of patient variants in these genes, and for a more extensive genome-wide screen for genes required for endolysosome function. This approach may also be adapted for drug screens to identify small molecules that rescue endolysosomal vacuolization.
•Spinal anaesthesia was induced with a prophylactic phenylephrine infusion.•Colloid was compared with crystalloid coload to prevent hypotension.•The incidence of hypotension was not significantly ...different between groups.
The optimal fluid strategy to prevent maternal hypotension during caesarean delivery remains unclear. This study aim was to compare the incidence of post-spinal anaesthesia hypotension in women receiving either colloid or crystalloid coload in the setting of prophylactic phenylephrine infusion during caesarean delivery.
Healthy mothers undergoing elective caesarean delivery under spinal anaesthesia were randomised to receive a rapid intravenous coload with 6% hydroxyethyl starch 130/0.4 10 mL/kg (colloid group) or balanced crystalloid solution (Plasma Solution A) 10 mL/kg (crystalloid group) during spinal anaesthesia. All women had a prophylactic phenylephrine infusion initiated at 25 μg/min immediately after the subarachnoid block and titrated to systolic blood pressure using a standardised protocol. The primary outcome was the incidence of hypotension (systolic blood pressure <80% of baseline) until delivery.
The incidence of hypotension was 50% in the colloid group and 62% in the crystalloid group (absolute difference, −12% 95% CI −33% to 9%; relative risk, 0.8 95% CI 0.56 to 1.14; P=0.314). No significant difference between groups was found in the number of hypotensive episodes (median 0.5 IQR 0 to 1 vs 1 0 to 2, P=0.132) or phenylephrine dose (675 IQR 425 to 975 μg vs 750 625 to 950 μg, P=0.109). The incidence of severe hypotension, symptomatic hypotension, bradycardia, nausea, and the neonatal outcomes were not significantly different.
This study found no benefit of colloid coload compared with crystalloid coload for preventing maternal hypotension in the presence of prophylactic phenylephrine infusion during caesarean delivery.
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