Heritability and genetic gain of some morphophysiological variables of durum wheat (Triticum turgidum var. durum)

The purpose of this work is to estimate genetic variability parameters and relationship among 11 agrophysiological traits studied on 18 experimental durum wheat and two checks under rainfed condition. The studied traits included the grain yield (YLD), plant height (PH), number of tiller per plant (NT), peduncle length (PL), flag length (FL), leaf dry weight (LDW), stem dry weight (STW), spike dry weight (SPW), spike height (SH), leaf area index (LAI), crop growth rate (CGR), relative growth rate (RGR), leaf area ratio (LAR) and net assimilation rate (NAR). Analysis of variance showed a significantly variation among genotypes for the characters PH, NT, PL, FL, LDW, STW, SPW, SH, LAR and NAR. High correlations were found among the PL, LDW, STW, SPW, LAR and NAR. Heritability estimates were high for PH, PL, LDW, STW and NAR. High genetic gains were observed for YLD, NT, PL, LDW, STW, SPW, LAR and NAR

Surgical treatment of postintubation tracheal stenosis: Iranian experience of effect of previous tracheostomy

Shahryar Hashemzadeh1, Khosrow Hashemzadeh2, Farzad Kakaei3, Raheleh Aligholipour4, Kamyar Ghabili51Tuberculosis and Lung Disease Research Center, 2Department of Cardiovascular Surgery, Shahid Madani Hospital, 3Department of General Surgery, 4Students Research Committee, 5Medical Philosophy and History Research Center, Tabriz University of Medical Sciences, Tabriz, IranBackground: Postintubation tracheal stenosis remains the most common indication for tracheal surgery. In the event of a rapid and progressive course of the disease after extubation, surgical approaches such as primary resection and anastomosis or various methods of tracheoplasty should be selected. We report our experience with surgical management of moderate to severe postintubation tracheal stenosis. We also compared intraoperative variables in postintubation tracheal stenosis between those with and without previous tracheostomy.Methods: Over a 5-year period from June 2005 to July 2010, 50 patients aged 14–64 years with moderate (50%–70% of the lumen) to severe (>70%) postintubation tracheal stenosis underwent resection and primary anastomosis. Patients were followed up to assess the surgical outcome. To study the effect of previous tracheostomy on treatment, surgical variables were compared between patients with previous tracheostomy (group A, n = 27) and those without previous tracheostomy (group B, n = 23).Results: Resection and primary anastomosis was performed via either cervical incision (45 patients) or right thoracotomy (five patients). In two patients with subglottic stenosis, complete resection of the tracheal lesion and anterior portion of cricoid cartilage was performed, and the remaining trachea was anastomosed to the thyroid cartilage using a Montgomery T-tube. There was only one perioperative death in a patient with a tracheo-innominate fistula. The length of the resected segment, number of resected rings, and subsequent duration of surgery were significantly greater in group A compared with group B (P < 0.05). Six months after surgery, the outcome was satisfactory to excellent in 47 (95.9%) patients.Conclusion: This surgical approach leads to highly successful results in the treatment of moderate to severe postintubation tracheal stenosis. In addition, previous tracheostomy might prolong the duration of surgery and increase the need for postoperative interventions due to an increase in the length and number of resected tracheal segments. Therefore, in the event of emergency tracheostomy in postintubation tracheal stenosis, insertion of the tracheostomy tube close to the stenotic segment is recommended.Keywords: trachea, tracheostomy, tracheal stenosis, intubation, tracheal resectio

Separation and quantification of diazinon in water samples using liquid-phase microextraction-based effervescent tablet-assisted switchable solvent method coupled to gas chromatography-flame ionization detection

This study used a liquid-phase microextraction-based effervescent tablet-assisted switchable solvent method coupled to gas chromatography-flame ionization detection as an eco-efficient, convenient-to-use, cost-effective, sensitive, rapid, and efficient method for extracting, preconcentrating, and quantifying trace amounts of diazinon in river water samples. As a switchable solvent, triethylamine (TEA) was used. In situ generation of CO(2) using effervescent tablet containing Na(2) CO(3) and citric acid changed the hydrophobic TEA to the hydrophilic protonated triethylamine carbonate (P-TEA-C). CO(2) removal from the specimen solution using NaOH caused P-TEA-C to be converted into TEA and led to phase separation, during which diazinon was extracted into the TEA phase. The salting-out process was helpful in enhancing extraction efficiency. In addition, a number of significant parameters that affect extraction recovery were examined. Under optimum conditions, the limit of detection and limit of quantitation were 0.06 and 0.2 ng/ml, respectively. The extraction recovery percentage and pre-concentration factor were obtained at 95 and 190, respectively, and the precision (inter- and intra-day, relative standard deviation , n = 5) was <5

Synergistic Effects of MWCNTs and High-Pressure Torsion-Induced Grain Refinement on Microhardness, Tribological Properties, and Corrosion Behavior of Cu and Cu/MWCNT Nanocomposites

In this study, ultra-fine grained Cu and Cu + carbon nanotube (CNT) nanocomposites were prepared through a processes combining flake powder metallurgy, hot pressing, and high-pressure torsion (HPT). The effects of grain refinement and CNT reinforcement on the microstructure, hardness, wear resistance, and corrosion behavior of the newly developed nanocomposites were investigated. The results indicated that the HPT process decreased the grain size of Cu and Cu + CNT by 67.7% and 68.1%, respectively, and increased their microhardness by 151% and 132%. The addition of CNTs substantially improved the tribological behavior of Cu by generating a mechanically mixed carbon- and oxide-rich layer. Moreover, polarization and electrochemical impedance spectroscopy tests revealed that the CNTs have a negligible adverse effect on the corrosion resistance of the Cu + CNT nanocomposites. The influences of the processing route and CNTs are discussed. Graphic Abstract: [Figure not available: see fulltext.] © 2021, The Korean Institute of Metals and Materials.11Nsciescopuskc

Synergistic role of carbon nanotube and SiCn reinforcements on mechanical properties and corrosion behavior of Cu-based nanocomposite developed by flake powder metallurgy and spark plasma sintering process

Hybrid-reinforced metals are novel composite materials in which nano-phases including nanoparticles and nanotubes/nanosheets are used simultaneously to reinforce metals or alloys to enhance physical, mechanical, wear and other properties. In this research, Cu/(CNT-SiC) hybrid nanocomposite was synthesized using flake powder metallurgy and spark plasma sintering method and the effects of hybrid reinforcements on microstructural, wear and corrosion properties of the developed material were investigated and compared with those of copper. Microstructural characterization showed reduction of average grain size from 419 to 307 nm and increase of low angle grain boundaries with the introduction and homogeneous dispersion of hybrid reinforcements. Mechanical tests indicated that the addition of hybrid SiC and CNT reinforcements substantially increased microhardness and reduced wear rate and friction coefficient of the Cu. Also, polarization and EIS tests revealed the suppressing of the anodic dissolution of the matrix, hindering the oxygen reduction reaction and 62.5% improvement of corrosion rate for the composite material. The effects of hybrid nano-reinforcements are presented and discussed.11Nsciescopu