THE EFFECT OF THE THERMOMECHANICAL PROCESSING ON THE MICROSTRUCTURE AND HARDNESS OF (Co25Cr15Fe20Ni40)83Al17 HIGH ENTROPY ALLOY

(Co25Cr15Fe20Ni40)83Al17 is a eutectic high entropy alloy (EHEA), which is composed of face centered cubic (FCC) and body centered cubic (BCC) phases. This dual (FCC+BCC) phase mixture provides good ductility and strength combination. In the scope of this study, it was aimed to analyze the effect of mechanical, thermal and thermomechanical processes on the microstructure and hardness of (Co25Cr15Fe20Ni40)83Al17 EHEA, which was produced by the vacuum arc melting and casting method. With this aim, cold and hot rolling as well as different annealing treatments were applied to the as-cast plates. The cold-rolling was performed at room temperature while the hot rolling temperature was varied in between 500-1000℃. The maximum deformation that can be applied was 50% and 60 % after cold and hot rolling, respectively. The limited deformability was attributed to the increased BCC/B2 content in the eutectic phase mixture with the applied deformation. The hardness was increased from 280 HV to 412 HV after 50% cold-rolling. A similar high hardness value (399 HV) was obtained after ~50% deformation at 750℃, indicating that the dynamic recrystallization had no significant effect up to 1000℃

Modal Analysis and Coupling in Metal-Insulator-Metal Waveguides

This paper shows how to analyze plasmonic metal-insulator-metal waveguides using the full modal structure of these guides. The analysis applies to all frequencies, particularly including the near infrared and visible spectrum, and to a wide range of sizes, including nanometallic structures. We use the approach here specifically to analyze waveguide junctions. We show that the full modal structure of the metal-insulator-metal (MIM) waveguides--which consists of real and complex discrete eigenvalue spectra, as well as the continuous spectrum--forms a complete basis set. We provide the derivation of these modes using the techniques developed for Sturm-Liouville and generalized eigenvalue equations. We demonstrate the need to include all parts of the spectrum to have a complete set of basis vectors to describe scattering within MIM waveguides with the mode-matching technique. We numerically compare the mode-matching formulation with finite-difference frequency-domain analysis and find very good agreement between the two for modal scattering at symmetric MIM waveguide junctions. We touch upon the similarities between the underlying mathematical structure of the MIM waveguide and the PT symmetric quantum mechanical pseudo-Hermitian Hamiltonians. The rich set of modes that the MIM waveguide supports forms a canonical example against which other more complicated geometries can be compared. Our work here encompasses the microwave results, but extends also to waveguides with real metals even at infrared and optical frequencies.Comment: 17 pages, 13 figures, 2 tables, references expanded, typos fixed, figures slightly modifie

Povezanost između polimorfizama XRCC1 ARG399GLN i P53 ARG72PRO s rizikom od raka želuca i debeloga crijeva u turskoj populaciji

Gastric cancer is one of the most common cancers of the gastrointestinal system, and its overall fi ve-year survival rate is still 15 % to 20 %, as it can mostly be diagnosed at an advanced stage. On the other hand, although colorectal cancer has a rather good prognosis, mortality is one half that of the incidence. As carcinogenesis is believed to involve reactive radicals that cause DNA adduct formation, impaired repair activity, and weakened tumour suppression, it would help to understand the role of the polymorphisms of nucleotide excision repair enzyme XRCC1 and of tumour suppressor gene p53 in gastric and colorectal cancers. Our study included 94 gastric cancer patients, 96 colorectal cancer patients, and 108 cancer-free individuals as control with the aim to see if there was an association between XRCC1 Arg399Gln and p53 Arg72Pro polymorphisms and cancer susceptibility. DNA was extracted from peripheral blood cells and genotypes were determined using the polymerase chain reaction-restriction fragment length polymorphism. Polymorphism p53 Arg72Pro was not associated with either gastric or colorectal carcinoma, while XRCC1 Arg399Gln was not associated with the increased risk of colorectal cancer. However, XRCC1 homozygous Gln allele at codon 399 was associated with 2.54 times higher risk of gastric cancer.Rak želuca najčešći je oblik karcinoma probavnoga sustava, a ukupno mu je preživljenje i dalje 15 % do 20 %, budući da se većinom dijagnosticira u poodmakloj fazi razvoja. S druge pak strane, premda rak debeloga crijeva ima prilično dobru prognozu, smrtnost je i dalje 50 %. Vjeruje se da je nastanak karcinoma povezan s reaktivnim radikalima koji uzrokuju stvaranje DNA-adukata, onemogućavaju popravak DNA te slabe supresiju tumora. Stoga bi bilo korisno razumjeti ulogu polimorfi zama gena za enzim XRCC1 koji sudjeluje u popravku isjecanjem nukleotida i tumor-supresorskoga gena p53 u nastanku raka želuca i debeloga crijeva. Naše je ispitivanje obuhvatilo 94 bolesnika s rakom želuca, 96 bolesnika s rakom debeloga crijeva te 108 kontrolnhih ispitanika (koji nisu oboljeli od bilo kojeg oblika raka) s ciljem da se utvrdi povezanost između polimorfi zama XRCC1 Arg399Gln i p53 Arg72Pro i sklonosti nastanku raka. DNA je dobiven iz stanica periferne krvi, a genotip utvrđen s pomoću metode lančane reakcije polimerazom - polimorfi zma restrikcijskih fragmenata na osnovi dužine (PCRRLFP). Polimorfi zam p53 Arg72Pro nije se pokazao povezanim s povećanim rizikom od raka želuca ili debeloga crijeva niti je XRCC1 Arg399Gln bio povezan s povećanim rizikom od raka debeloga crijeva, ali je zato rizik od raka želuca u homozigotnih nositelja ovoga polimorfi zma bio 2,54 puta veći

Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study

Background Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study. Methods We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income. Results Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income. Conclusion At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio

Prevalence and Population Attributable Risk for Chronic Airflow Obstruction in a Large Multinational Study

Rationale: The Global Burden of Disease programme identified smoking, and ambient and household air pollution as the main drivers of death and disability from Chronic Obstructive Pulmonary Disease (COPD).Objective: To estimate the attributable risk of chronic airflow obstruction (CAO), a quantifiable characteristic of COPD, due to several risk factors.Methods: The Burden of Obstructive Lung Disease study is a cross-sectional study of adults, aged≥40, in a globally distributed sample of 41 urban and rural sites. Based on data from 28,459 participants, we estimated the prevalence of CAO, defined as a post-bronchodilator one-second forced expiratory volume to forced vital capacity ratio Measurements and Main Results: Mean prevalence of CAO was 11.2% in men and 8.6% in women. Mean PAR for smoking was 5.1% in men and 2.2% in women. The next most influential risk factors were poor education levels, working in a dusty job for ≥10 years, low body mass index (BMI), and a history of tuberculosis. The risk of CAO attributable to the different risk factors varied across sites.Conclusions: While smoking remains the most important risk factor for CAO, in some areas poor education, low BMI and passive smoking are of greater importance. Dusty occupations and tuberculosis are important risk factors at some sites

Cohort Profile: Burden of Obstructive Lung Disease (BOLD) study

The Burden of Obstructive Lung Disease (BOLD) study was established to assess the prevalence of chronic airflow obstruction, a key characteristic of chronic obstructive pulmonary disease, and its risk factors in adults (≥40 years) from general populations across the world. The baseline study was conducted between 2003 and 2016, in 41 sites across Africa, Asia, Europe, North America, the Caribbean and Oceania, and collected high-quality pre- and post-bronchodilator spirometry from 28 828 participants. The follow-up study was conducted between 2019 and 2021, in 18 sites across Africa, Asia, Europe and the Caribbean. At baseline, there were in these sites 12 502 participants with high-quality spirometry. A total of 6452 were followed up, with 5936 completing the study core questionnaire. Of these, 4044 also provided high-quality pre- and post-bronchodilator spirometry. On both occasions, the core questionnaire covered information on respiratory symptoms, doctor diagnoses, health care use, medication use and ealth status, as well as potential risk factors. Information on occupation, environmental exposures and diet was also collected

The frequency of Malassezia as a causative agent in folliculitis [Folikülitte etken olarak Malassezia sikli?i]

Objective: It has been known that Malassezia spp. can play role in different dermatologic diseases. The aim of this study is to detect identification of Malassezia spp. species in folliculitis patients. CopyrightMaterial and Methods: One hundred and three patients with folliculitis who attended Ege University Faculty of Medicine Dermatology and Venereology outpatient clinic between January 2010-November 2012 included in the study. The patients were diagnosed as Malassezia folliculitis based on direct microscopic examination and culture of the material taken from the lesion of folliculitis. Samples inoculated in Sabouraud dextrose agar (SDA) with sterile olive oil and modified Dixon agar. Catalase and esculin tests performed to isolated colonies and cultured in Tween-20, 40, 60, and Tween-80 mediums. Species were diagnosed by according to these tests and growth properties.Results: Of 103 patients, 40 (38.8%) female and 63 (61.2%) male. Three of the patients (12.9%), direct microscopic examination was negative but in culture was positive. In eighteen (17.4%) patients not only direct examination but also cultures were found positive. It was determined that in 9 (8.7%) patients, direct examination was positive but no cultural isolation found. 29.1% of the folliculitis patients Malassezia spp. was detected as a causative agent. In all of the cultures, Malassezia globosa was isolated.Conclusion: This is the first study about the frequency of Malassezia species in folliculitis in our region. In this study the only agent isolated is M. globosa. © 2014 by Türkiye Klinikleri

A comparison fentanyl and remifentanil in terms of anesthesia quality and cost for fast-track cardiac anesthesia [Fast-track Kardiyak Anestezide Fentanil ve Remifentanilin Anestezi Kalitesi ve Maliyet Yönünden Karşilaştirilmasi]

The aim of this study was to compare fentanyl and remifentanil in 'fast-track' cardiac anesthesia of patients undergoing cardiopulmonary bypass (CPB) in terms of anesthesia quality and cost. Anesthesia was induced with lidocaine, propofol, 10 µg.kg-1 fentanyl (Group Fentanyl) or 1-2 µg.kg -1 remifentanil (Group Remifentanil) and 0.1 mg. kg -1 pancuronium bromide. In both groups, patients were given 1-6 mg.kg -1.h -1 propofol before and after cardiopulmonary bypass (CPB) and 1-2 mg.kg -1.h -1 propofol during CPB. Patients were given 5 µg.kg -1 fentanyl before sternotomy and 2 µg.kg -1 fentanyl during CPB (Group Fentanyl) or 0.25-1 µg.kg -1.min -1 remifentanil before and after CPB and 0.125-0.25µg.kg -1. min -1 remifentanil during CPB (Group Remifentanil). Postoperative analgesia was maintained with fentanyl or remifentanil infusion plus 0.02 mg. kg -1. h -1 morphine. Mean arterial pressure and heart rate values, VAS scores, morphine consumption, times to recovery, extubation and discharge from hospital were recorded. Hemodynamic changes, VAS scores, morphine consumption, times to recovery, extubation and discharge from intensive care unit and hospital, cost of anesthetic and vasoactive agents were found to be similar in both groups (p>0.05). Fentanyl and remifentanil were found to be similar in terms of "fast-track" cardiac anesthesia quality and cost in patients undergoing coronary artery bypass surgery

Value of preoperative spirometry to predict postoperative pulmonary complications

PubMedID: 8857323In order to determine the incidence of postoperative pulmonary complications (POPC) and the value of preoperative spirometry to predict pulmonary complications after upper abdominal surgery, 24 women and 36 men (total 60 patients) were studied prospectively (mean age 48.3 years). On the day before the operation and for 15 days after the operation, each patients's respiratory status was assessed by clinical examination, chest radiography, spirometry and blood gas analysis, and patients were monitored for pulmonary complications by a chest physician and a surgeon independently. In this study, postoperative pulmonary complications developed in 21 (35%) patients (pneumonia in 10 patients, bronchitis in nine patients, atelectasis in one patient, pulmonary embolism in one patient). Of 31 patients with abnormal preoperative spirometry, 14 (45.2%) patients showed complications, whereas among 29 patients with normal preoperative spirometry, 7 (24.1%) patients showed complications (P < 0.05). The incidence of POPC was higher in patients with advanced age, smoking, preoperative abnormal findings obtained from physical examination of the chest, higher ASA class and longer duration of operation. The sensitivity (0.76) and specificity (0.79) of abnormal preoperative findings obtained from physical examination to predict POPC were higher than abnormal preoperative spirometry (0.67 and 0.56 retrospectively). There was no significant difference between patients with and without pulmonary complications in regard to weight, serum albumin, type of incision, incidence of abnormal preoperative blood gases and duration of postoperative hospital stay. We conclude that POPC is still a serious cause of postoperative morbidity. Multiple risk factors include preoperative abnormal spirometry responsible for development of POPC. If used alone, spirometry has limited clinical value as a screening test to predict POPC after upper abdominal surgery