Comparison of Tensile Properties of Nb Grain Refined A206 Alloy by Gravity and Tilt Casting

Turbulent filling of a mould is one of the ways to introduce extrinsic defects into the cast part that could deteriorate many properties of any casting. The turbulence can be easily eliminated by counter gravity casting. In gravity casting, tapered downsprue, tapered runner is needed such that the mould cavity is filled counter-gravity from the bottom which is the only best way to eliminate turbulence during filling. Tilt casting method also exists which has the potential to quiescently transfer the liquid into the mould cavity. In this work, gravity and tilt casting methods were used to evaluate the tensile properties of Nb grain refined 206 alloy. Three different Nb contents were investigated: 0.025, 0.05 and 0.1 wt% ratios and it was found that 0.05 wt% revealed the highest tensile properties. On the other hand, when the intrusion of surface folded oxides was eliminated during filling, it was found that mechanical properties were increased significantly, and particularly, the toughness was increased by two folds when tilt casting was applied compared to gravity casting

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Piano-stool Ru (II) arene complexes that contain ethylenediamine and application in alpha-alkylation reaction of ketones with alcohols

WOS: 000465346500010A series of piano-stool Ru (II) complexes (Ru1-7) bearing ethylenediamine with aryl and aliphatic groups were prepared and fully characterized by H-1, C-13, F-19 and P-31 NMR spectroscopy, FT-IR and elemental analysis. The crystal structures of Ru2-4 and Ru-7 were determined by X-ray crystallography. They were successfully applied to the alpha(alpha)-alkylation of aliphatic and aromatic ketones with alcohols via the borrowing hydrogen strategy in mild reaction conditions within a short time. The catalytic system has a broad substrate scope, which allows the synthesis of alpha alkylated ketones with excellent yields. The electronic and steric effects of complexes on catalytic activity were analysed. The influence of the carbon chain length of the ligand on the alpha-alkylation reaction of ketones was also investigated. The catalytic cycle was also examined by H-1-NMR spectroscopy in d(8)-toluene.Ege University and Scientific and Technological Research Council of Turkey (TUBITAK) [214Z098]The authors thank Ege University and Scientific and Technological Research Council of Turkey (TUBITAK, Project Number: 214Z098) for the financial support. The authors acknowledge Scientific and Technological Research Application and Research Center, Sinop University, Turkey, for the use of the Bruker D8 QUEST diffractometer

Characterization of Casting Properties of Rare-Earth Modified A356

Al-Si alloys are an attractive choice of light alloys due to their low density and high mechanical properties. The application areas include automotive and aerospace parts. With the increased requirements and demands on such applications, the researchers have focused on the enhancement of properties with the addition of novel alloying elements. In the last decade, modification of microstructure by rare-earth element additions has become popular. In this work, systematical tests were carried out by using fluidity test mold that has 8 arms with different thicknesses and tensile test mold that contains 10 bars to statistically analyze the mechanical properties. Different ratios ranging from 0.05 to 1 wt% of Er, Sc, Y, and V were added to Al-7Si alloys. The addition of 0.1 wt% Sc shows the highest fluidity whereas V additions have the lowest. Statistically, Sc addition revealed the highest reproducible results in terms of tensile properties where Y had the highest scatter. Er additions have the highest UTS and elongation at fracture

Synthesis and catalytic applications of Ru and Ir complexes containing N,O-chelating ligand

turkmen, hayati/0000-0001-7411-2652; Kavukcu, Serdar Batikan/0000-0002-1168-5012WOS: 000575166800007A series of monometallic complexes (Ru1-3, Ir-1(-3)) which have N,O-chelating ligand (pyrazine-2carboxylate (1), pyridine-2-carboxylate (2), quinoline carboxylate(3) and bimetallic complexes (Ru-4,Ru-5, Ir-4(,5)) bridged by pyrazine-2,3- dicarboxylate (4) and imidazole-4,5-dicarboxylate(5) were synthesized and characterized by H-1-, C-13 NMR, FT-IR, and elemental analysis. the crystal structure of Ir-2 was determined by X-ray crystallography. the complexes (Ru1-5, Ir1-5) were applied to investigate the electronic and steric effect of ligand in their catalytic activities in transfer hydrogenation and alpha(alpha)-alkylation reaction of ketones with alcohols. the activities of iridium complexes (Ir1-5) were much more efficient than ruthenium complexes (Ru1-5). the highest activity for both reactions was observed for the complex (Ir2 ) with pyridine-2-carboxylate. the Ir hydride species was monitored for both reactions. (C) 2020 Elsevier B.V. All rights reserved.Ege UniversityEge University [17-FEN-058]The authors thank to Ege University Scientific Research Fund (17-FEN-058) for the financial support. the authors acknowledge Scientific and Technological Research Application and Research Center, Sinop University, Turkey, for the use of the Bruker D8 QUEST diffractometer

Stereological Estimation of the Orbital Volume: A Criterion Standard Study

Several methodologies have been proposed to assess the orbital volume (OV). However, we have not seen a criterion standard study evaluating the results of the methodologies for the assessment of OV In the current study, the actual OV of 9 dry skulls was measured using the water filling method as the criterion standard. Consecutive computed tomographic sections at a thickness of 1.5 mm were used to estimate the OV by means of the point counting method. The mean (SD) of the OV measured by the water filling method was 17.84 (1.56) cm(3). By using the point counting method, it was 17.05 (1.69) cm(3). There was no statistically significant difference between sides (P > 0.001). The results of the OV values obtained by the two methods were compared statistically. The agreements between the two methods were also evaluated using the Bland-Altman plots. There was no statistically significant difference between the OV measurements obtained by the stereological technique and water filling method. The described method could be used for the assessment of OV in vivo