88 research outputs found

    Growth and uptake of sodium and potassium in broad bean (Vicia faba L.) under salinity stress

    Get PDF
    Vicia faba L. (broad bean or faba bean), a food crop of worldwide importance, is moderately tolerant of saline conditions, such as are increasingly common in Mediterranean countries and in Turkey. Our objective was to determine the influence of two salinity levels [50 and 100 mM sodium chloride (NaCl)] and two potassium salts, potassium nitrate (KNO3) (N1 and N2) or potassium acetate (CH3COOK) (A1 and A2), on the development of seedlings of two cultivars of broad bean (cvs. Eresen 87 and Filiz 99) grown in pots of perlite under controlled greenhouse conditions. Flame photometer (FP) analysis of tissues from roots, stems, and leaves of 3-month-old seedlings showed significant differences in growth, internodal length, and potassium (K+)/sodium (Na+) ratios. The FP analyses revealed that Na+ was the ion most responsible for inhibition of growth parameters seen in both cultivars and salt treatments. K+ contents were consistently higher in cv. Filiz 99 than in cv. Eresen 87. Possible correlations between these data and the tolerance to salinity of these cultivars are discussed

    Application of experimental design on determination of aluminum content in saline samples by adsorptive cathodic stripping voltammetry

    Get PDF
    Adsorptive cathodic stripping voltammetric determination of aluminum at ng mL-1 levels in salt samples based on the metal complexation with Calcon (1-(2-hydroxynaphthylazo)-2 naphthol-4-sulfonic acid) and the subsequent adsorptive deposition onto a hanging mercury drop electrode was studied. Central composite design was used as a design method. Several chemical and instrumental parameters (pH, ligand concentration, deposition time, deposition potential, and complexing time) were involved in the experimental design. Analytical parameters such as repeatability, linearity, and accuracy were also investigated and the detection limit was found as 0.32 ng mL-1.Ege University research fund (Project no: 2004 Fen 071

    Ligand effects in metal catalyzed reactions

    Get PDF
    Metal katalizli reaksiyonlarda, özellikle geçiş metali, bileşiği veya organometalik bileşiği katalizör olarak kullanılır. Metal katalizinde ligand, katalizör yapısında veya reaksiyon ortamında katılır. Ligand kullanılarak, reaksiyonun hızı, verimi ve kimyasal seçiciliği kontrol edilebildiği gibi, asimetrik ligand kullanılarak stereoseçicilik de sağlanabilir. Metal katalizli reaksiyonlarda ligandla hızlandırılmış kataliz, lâboratuvarda ve endüstride çok önemlidir; fakat ligandla yavaşlatılmış kataliz konusunda çok az araştırma yapılmıştır.Alkenlerin osmiyum katalizli dihidroksillenmesi, ter-amin ligandlar kullanılarak ligandla hızlandırılmış veya yavaşlatılmış olarak yürütülebilir. Grignard ve organolityum reaktiflerinin bakır katalizli reaksiyonlarında reaksiyonun verimi ve kimyasal seçiciliği, ligandlı Cu(I) bileşikleri ile kontrol edilebilir. Anahtar Kelimeler: Dihidroksilleme, eşleşme, kataliz, ligand, metal katalizi.For metal catalyzed reactions, generally a transition metal, a transition metal compound or an organometallic complex is used as a catalyst. A ligand can act either as complexed to the metallic catalyst or as one of the reactants. A ligand has four different modes of operation: (i) to accelerate or decelerate the catalysis, (ii) to control the product yield, (ii) to control chemoselectivity, and (iii) to provide stereocontrol in the case of chiral ligands.  The use of ligand accelerated catalysis has become increasingly important for asymmetric synthesis both in laboratory and industrial scale; however, ligand decelerated catalysis has not been investigated in detail. In osmium catalyzed dihydroxylation of alkenes in the presence of nitrogen donor ligands, ligand accelerated or decelerated catalysis can take place as a result of some combination of substrate alkene and ligand. Cu(I) catalyzed C-C and C-heteroatom coupling reactions of Grignard reagents and organolithiums have revealed that reaction yield and chemoselectivity  can be controlled by ligand complexed  Cu(I) catalysts and one shoud not use automatically CuI, the popular catalyst for coupling, but rather examine several Cu(I) compounds and their complexes to find the optimal one. A research on "ligand controlled catalysis" is offered for optimization of all reaction parameters, i.e. rate, yield, chemo- and stereocontrol in metal and ligand catalyzed reactions. Keywords: Dihydroxylation, coupling, catalysis, ligand, metal catalysis

    Decoupled Modular Regularized VMS-POD for Darcy-Brinkman Equations

    Get PDF
    We extend the post-processing implementation of a projection based variational multiscale (VMS) method with proper orthogonal decomposition (POD) to flows governed by double diffusive convection. In the method, the stabilization terms are added to momentum equation, heat and mass transfer equations as a completely decoupled separate steps. The theoretical analyses are presented. The results are verified with numerical tests on a benchmark problem

    Effects of Different Applications on Postoperative Seroma Formation and Wound Healing Following Mastectomy and Axillary Dissection in Rats

    Get PDF
    The most frequent postoperative complication after breast surgery is seroma formation. Seroma occurs due to lymphatic and vascular fluid leakage into the dead space created by surgical dissection. The objective of the research was to evaluate the effects of local fibrin glue, tetracycline, talc applications, and flap fixation technique on reducing seroma formation after mastectomy and axillary dissection. In addition, we aimed to determine the level of efficacy for these applications, as well as to identify the most appropriate method to be used in operations with high risk of seroma formation. Materials and Methods. This experimental study was conducted using a total of 60 female Wistar albino rats. They were allocated into six groups and each comprised ten rats. Unilateral mastectomy and axillary dissection were performed on all the rats. Local applications of fibrin glue, tetracycline, talc, and alcoholic iodine were performed in four separate groups. Flap fixation technique was applied in one group and those rats that did not receive any intervention constituted the control group. On the 10th postoperative day, seroma was aspirated under anesthesia, and the amount of seroma fluid was recorded. Seroma fluid was analyzed for interleukin 1-β, vascular endothelial growth factor, and C-reactive protein levels. Tissue samples were obtained from the skin overlaying the dissection area, the axilla, and the thoracic wall. Wound healing was evaluated with histopathological examination. Results. Seroma volume was lower and the wound healing scores were the highest in the flap fixation group and the tetracycline group as compared to the control group. However, the alcoholic iodine group and the talc group had a greater amount of seroma (p < 0.05). There was no difference between the fibrin glue group and the control group. Conclusions. In our mastectomy model, local application of alcoholic iodine and talc substances caused more wound site problems and postoperative seroma formation. While fibrin glue did not cause wound site problems, it did increase seroma formation. These three substances were determined to be inefficacious in postoperative seroma formation. Local tetracycline application and flap fixation technique were found to reduce postoperative seroma and benefit wound healing

    Long-Term Follow-up Results of Primary Canaliculitis Patients

    Get PDF
    Objectives:To evaluate the demographic characteristics, clinical presentation, microbiologic profile, and treatment results of patients with primary canaliculitis.Materials and Methods:Patients diagnosed and treated for primary canaliculitis between May 2014 and May 2021 were analyzed retrospectively.Results:There were 26 patients with primary canaliculitis, including 17 females (65.4%) and 9 males (34.6%) with a mean age of 50.6±16.4 years (range: 9-80 years). Canaliculitis affected the right eye in 11 patients, the left eye in 13 patients, and bilateral involvement was seen in 2 patients. Inferior canaliculus involvement was more frequent (73%). The most common complaint was epiphora (46.1%). Five patients (19.2%) were wrongly diagnosed as chronic conjunctivitis. The time interval between the beginning of symptoms and canaliculitis diagnosis was 18.2±14.3 months (range: 1-60 months). Canaliculotomy and curettage of canalicular content with dacryolith removal were performed in 23 patients. After surgery, antibiotic irrigation of the canaliculus was added to the treatment regimen in 12 of these 23 patients. Intracanalicular antibiotic therapy was administered to the remaining 3 patients. The most cultured organism was Actinomyces (6 patients). Gemella (1 patient), Porphyromonas (1 patient), Candida parapsilosis (1 patient), Citrobacter koseri (1 patient) were also grown in culture. The follow-up time of patients was 26.2±23.7 months (range: 6-83 months). All symptoms and findings resolved in all patients in one month. In two patients, recurrence occurred at 4 and 16 months after surgical treatment. With appropriate treatment, no further recurrence was seen in either patient over 24-month follow-up. One patient presented with iatrogenic canaliculus blockage during follow-up.Conclusion:Primary canaliculitis is often overlooked and can be misdiagnosed. The most common symptom was epiphora. All patients with epiphora and chronic conjunctivitis should be examined carefully for canaliculitis

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

    Get PDF
    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030
    corecore