267 research outputs found
Metal Endüstrisi, Alüminyum ve Gelecek
20. yüzyılda ham maddeler ve metallerle ilgili istatistiklerde değerlendirmeler genellikle tonaj esaslı olarak yapılırdı. İçinde bulunduğumuz yüzyılda (21. yy) ise küresel ekonomi nedeniyle değerlendirmelerde fiyatlar ve rekabet koşulları belirleyici olmuştur. Daha da öte ürünlere iki türlü fiyat verilir olmuştur. Bunlardan biri emtialardaki gerçek fiyat ise, diğeri Çin dominasyonunun şaşırtan düşük fiyatıdır. Bu gün, Çin ülke olarak sadece küresel fiyatları değil, ekonomik göstergeleri de yönetmeye başlamıştır.
Dalgalı küresel ekonominin istikrarlı yarım adası olmaya namzet olan Türkiye’mizin işi bu konjektürde kolay değildir. Hedefi yakalamamız için ekonomik ve siyasal enstrümanları iyi yönetmemiz ve yapay/doğal krizlerden kaçınmamız gerekmektedir.
Bu çalışmada metal endüstrisi, fiyatlar ve gelişmeler alüminyum sektörümüz özelinde incelenmiştir
Health and Safety in Manufacturing of Aluminium Profile
Bir işyerinin kimliğini işyerinin yöneticileri ve çalışanları belirlemektedir. Yöneticilerin tutum ve davranışları işçi sağlığı ve iş güvenliği için çok önemlidir. Düzensiz iş akışı, uygun olmayan çalışma ortamı ve eksik donanım çalışanların sağlığı ve iş güvenliğini olumsuz etkilemektedir.
İşini tanıyan ve çalışmanın getirdiği riskleri bilen insanların iş kazası geçirme oranları daha azdır. Dikkatli çalışmak ve gerekli tedbirleri almak ilk önce çalışanın görevidir.
Çalışanların ruhsal ve fiziksel özellikleri, iş kazaları ve mesleki hastalıkların %50 ‘ye yakınını oluşturmaktadır.
Bu çalışmada, alüminyum profil üretim şirketlerinde işçi sağlığı ve iş güvenliği etkenleri tartışılmaktadır
Preparation and characterization of polyacrylonitrile membranes modified with polyelectrolyte deposition for separating similar sized proteins
One of the challenges faced by ultrafiltration membranes is to separate proteins with a small difference in their molecular weights. Recently, some researchers tried to overcome this problem by using charged membranes. This study examined the use of layer by layer deposition of polyelectrolytes on the chemically-modified polyacyronitrile membrane to increase the selectivity of the ultrafiltration. The membranes were prepared by wet-phase inversion technique and polyethylenimine (PEI) and alginate (ALG) were chosen as cationic and anionic polyelectrolytes for the modification of the surfaces. Sieving coefficient data were obtained with myoglobin and lysozyme as model proteins. The influences of solution pH, ionic strengths of the protein and polyelectrolyte solution and the number of polyelectrolyte bilayers on both selectivity and throughput were investigated. The highest selectivity and throughput were achieved with the 1-bilayer PEI-ALG coated polyacrylonitrile (PAN) membrane. Increasing the number of coating bilayers or the ionic strength of the protein solution or adding salt into the polyelectrolyte coating solution decreased both the maximum selectivity and throughput of the modified membranes.Izmir Institute of Technology; 2009IYTE0
Genetic transformation of common beans (Phaseolus vulgaris L.) through Agrobacterium tumefaciens carrying Cry1Ab gene
Background: Seed beetles are one of the most important causes of yield loss in bean production. It is essential to develop resistant varieties in the fight against these pests. Agrobacterium-based gene transformation is the most widely used breeding method worldwide to develop insect-resistant varieties. Methods and results: Embryonic axes and plumule explants were obtained from Agrobacterium tumefciens treated mature zygotic embryos of low and high raw protein-based common bean cultivars Akman 98 and Karacaşehir 90. Agrobacterium tumefaciens contained a synthetic Bacillus thuringiensis insecticidal crystal protein gene (Bt Cry1Ab) controlled by the 35S promoter and NOS terminator sequences. The transformation event was genotype and explant dependent. The plumule explants could not withstand kanamycin-based selection pressure and died. It was possible to get two transgenic plants using embryonic axis explants of low protein cultivar Akman 98. These results were validated using GUS analysis, PCR, RT-PCR, bioassay analysis, and ELISA test from the samples taken from T0 and T1 generations. Bioassay tests showed that these plants were protected from the damage of legume seed insects (Bruchus spp.). Conclusions: The results are very encouraging and may help in producing better transgenic common bean germplasm leading to safe agriculture and reducing environmental pollutions. © 2022, The Author(s), under exclusive licence to Springer Nature B.V
The effects of rivaroxaban, an oral anticoagulant, on human IVD primary cultures
Introduction: The present study aimed to investigate the potential effects of rivaroxaban, an oral anticoagulant that inhibits the effects of factor Xa, on intact intervertebral disc tissue cells and the extracellular matrix (ECM). Material and methods: Rivaroxaban was applied to primary human cell cultures prepared from tissues of the intervertebral disc. Comparative molecular analyses were performed on non-drug-treated control group samples. Descriptive statistics were presented as the mean +/- standard deviation. An analysis of variance test was performed to determine whether there were significant differences in the mean across the groups. When differences across groups were observed, Tukey's honestly significant difference post-hoc test was used for multiple pairwise comparisons. The significance of the obtained data was determined statistically. The alpha significance value was < 0.05. Results: The cells in the control group and in the rivaroxaban-treated group were viable, healthy, and proliferated (p < 0.05). However, the expression levels of the chondroadherin gene (CHAD), cartilage oligo matrix protein (COMP), matrix metalloproteinase (MMP)-13, and MMP-19 genes were changed (p < 0.05). Conclusions: Although rivaroxaban does not suppress cell proliferation due to morphological, biological, and biochemical changes in the intervertebral disc tissue, it may change the expression of genes that are related to ECM maintenance
Pediatric tracheotomy: 5-years of experiences at a tertiary care center
Objective: To describe specific indications and complications of pediatric tracheostomies performed in our tertiary care children’s hospital between 2015 and 2020. Materials and Methods: A retrospective study analyzing charts of pediatric tracheostomies utilizing the maturation suture technique was conducted. The review included patient data covering a 5-year period, commencing on the 1st of January 2015 through the 31st of May 2020. Results: Fifty-five patients (33 females, 22 male) were included in the study. A tracheostomy was performed to address complications arising from prolonged ventilation in 48 children (87%) or upper airway obstruction in 7 children (13%). There was one intraoperative complication that resulted in death. There was one early postoperative complication (2%) (one child suffered accidental decannulation and the cannula was replaced without further incident). There were 7 late postoperative complications all featuring peristomal granulation tissue (13%). There were 16 deaths; however, only one resulted from the tracheostomy as outlined above. Eight patients (15%) were successfully decannulated. In 6 cases, the tracheostomy was spontaneously closed. Repair of tracheoesophageal fistula was required in two patients. Conclusion: Currently, the tracheostomy is the preferred course of treatment. Though it can potentially lead to severe complications in children, instances of this occurring are rare. Therefore, a tracheostomy should be performed by a multidisciplinary team following predetermined rules in a specialized center
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