Assessment of imidacloprid toxicity on reproductive organ system of adult male rats

In the current study it was aimed to investigate the toxicity of low doses of imidacloprid (IMI) on the reproductive organ systems of adult male rats. The treatment groups received 0.5 (IMI-0.5), 2 (IMI-2) or 8 mg IMI/kg body weight by oral gavage (IMI-8) for three months. The deterioration in sperm motility in IMI-8 group and epidydimal sperm concentration in IMI-2 and IMI-8 groups and abnormality in sperm morphology in IMI-8 were significant. The levels of testosterone (T) and GSH decreased significantly in group IMI-8 compared to the control group. Upon treatment with IMI, apoptotic index increased significantly only in germ cells of the seminiferous tubules of IMI-8 group when compared to control. Fragmentation was striking in the seminal DNA from the IMI-8 group, but it was much less obvious in the IMI-2 one. IMI exposure resulted in elevation of all fatty acids analyzed, but the increases were significant only in stearic, oleic, linoleic and arachidonic acids. The ratios of 20:4/20:3 and 20:4/18:2 were decreased and 16:1n-9/16:0 ratio was increased. In conclusion, the present animal experiments revealed that the treatment with IMI at NOAEL dose-levels caused deterioration in sperm parameters, decreased T level, increased apoptosis of germ cells, seminal DNA fragmentation, the depletion of antioxidants and change in disturbance of fatty acid composition. All these changes indicate the suppression of testicular function

Karton ve oluklu mukavva ambalaj üretiminde optimizasyon

ÖZETBu çalışma, karton ve oluklu mukavva ambalaj üretimi faaliyetinde bulunan matbaa işletmesinde optimal makine ataması yoluyla üretimin optimizasyonuna yönelik bir çalışmadır. Üretim optimizasyonunda minimizasyon yöntemi kullanılmıştır. Yani minimum sürede ve/veya minimum maliyetle işin yapılabilmesi için uygun istasyonların ( makinelerin ) belirlenip, bu makinalara işlerin optimal bir şekilde atanması hedeflenmiştir.Çalışmanın ikinci bölümünde ambalaj tipleri konusunda, üçüncü bölümünde ise karton ve oluklu mukavva hammaddeleri hakkında bilgi verilmiştir. Dördüncü bölümde genel olarak üretim tipleri anlatılmış ve matbaa üretiminin bu üretim tipleri içindeki yeri belirlenmiştir. Beşinci bölümde ise matbaa üretiminin aşamaları detaylı olarak açıklanmıştır. Karton ve oluklu mukavva ambalaj üretimi baskı, kesim ve katlama-yapıştırma aşamalarında birleşmektedirler. Bu üretim aşamalarına ek olarak oluklu mukavva ambalaj üretiminde laminasyon ve oluklu mukavvanın üretimi aşamaları da vardır; fakat bu aşamalardaki üretim verileri sağlıklı olarak alınamadığından dolayı baskı, kesim ve katlama yapıştırma bölümleri üzerinde durulmuştur. Baskı öncesindeki konstrüksiyon tasarımı ve grafik tasarım aşaması üretimin alt aşamaları olmalarına karşın tasarımın süresi konusunda bir standart belirlenmesi güç olduğundan, kapsam dışında bırakılmıştır. Yapılan işlemler tasarımı bitmiş, baskıya hazır siparişler için ele alınmıştır.Altıncı bölüm, üretimin optimizasyonu için sistemin kurulup açıklandığı bölümdür. Sistemin gerçek verilere dayanması amacı ile model bir karton ambalaj üreticisi seçilmiş ve üretimle ilgili veriler gerçek üretim şartlarında tespit edilmiştir. Makinelerin saatlik maaliyetleri firma tarafından daha önceden hesaplandığı için tezde aynı değerler veri olarak kullanılmıştır. Kurulan sistemin amaç fonksiyonu, imalat süresinin ve/veya makinelerin saatlik maliyetlerinin minimizasyonunun yapılmasına dayalıdır.Yapılan çalışmada; arıza, bakım, revizyon vb. üretime ara verme süreleri maliyetlere dahil edilmemiştir. Eski kayıtlardaki personel performanslarının üretim sürelerine nasıl yansıdığı araştırılmamıştır. Hatalı planlama ve termin planının, firmanın yıllık üretim kapasitesindeki kayıpları ve maliyete etkileri ihmal edilmiştir. Günün değişik saatlerinde üretim kapasitesinin farklılığı belirlenmemiştir.Optimizasyonun sağlanması için aşağıdaki yol izlenmiştir:1) Model matbaada bulunan makinelerin geçmiş altı aylık vardiya raporlarındaki üretim verilerine dayanarak yeni gelecek siparişlerin üretilebilecekleri süreyi tahmin etmek amacı ile SPSS paket programı kullanılarak regresyon analizleri yapılmış, regresyon doğruları çizilmiş ve doğru denklemleri oluşturulmuştur. Bu işlemler yapılırken kullanılan serilerin güvenilirliği Korelasyon katsayısı ile test edilmiştir.2) Her ana üretici işyeri için hangi siparişin hangi makinelerle üretilebileceğinin tespiti için makinelerin teknik özellikleri belirlenerek kısıtlar oluşturulmuştur. Buna bağlı olarak da sipariş alınırken siparişin kriterleri tespit edilmiştir.3) Örnek bir sipariş üzerinde makine kapasiteleri kullanılarak hangi makinelerin bu siparişi üretebileceği tespit edilmiştir. Tespit edilen makinelerin regresyon denklemleri kullanılarak siparişi ne kadar sürede üretebilecekleri bulunmuş ve saatlik maliyetleri önceki verilerden hesaplanarak elde edilen değerler ana tabloya aktarılmıştır. Bu işlemler basit bir akış diyagramı ile beşinci bölümde gösterilmiştir. Bu işlemler toplam otuzbir örnek sipariş için yapılmış, fakat tezde örnek olarak hesapları basamak basamak yapılan sipariş haricindekilerin hesaplamaları, Excel paket programında kurulan modelle yapılmış ve ana tabloya aktarılmıştır.4) Bundan sonra, siparişleri üretebilecek makineler arasından minimum süre ve maliyet açısından en uygununun seçilip yüklemesi yapılmaktadır. Bu işlemler sonucunda çizilen grafikler ile optimizasyonun gerçekleşip gerçekleşmediği test edilmiştir.Yedinci bölümde ise kurulan sistem hakkında tespitler yapılmış ve sistemin verimli çalışması için tavsiyelerde bulunulmuştur.SummaryIn this thesis, a study on the optimization of carton and corrugated packaging production, and machine assignment was carried out. Minimization technique was applied for optimization of the production. This study aimed to decide the appropriate machines for orders and to make machine assignments for minimum production time and minimum cost.The second part of the study explains the types of packaging. The third part contains technical knowledge about carton and corrugated rough materials. In the fourth part, types of production were explained. The printing production was discussed, compared the differences and similarities between the others, and the production type of printing was determined. In the fifth part, the steps of printing production was explained. The production steps, printing, die cutting and gluing are the same steps for both carton and corrugated package production. There are other steps for corrugated packaging, called production of corrugated carton and lamination. These steps are eliminated from the study because there weren't appropriate data found around them. This study was focused on the production steps printing, die cutting and gluing. Constructional and graphic design which are the steps of prepress, are also eliminated because there is no standard time for design. The optimization study is applied on only ready to print orders.In the sixth part, the system was set for optimizing the production. The data were taken from a real carton packaging company in real production conditions. The hourly costs of machines which were calculated by the company are used in the study. The main function of the system is based on the minimization of the production time and hourly costs of the machines.In this study; machine breakdowns, maintenance, revision and production breaks are not noticed and added into the costs. The effects of personnel performances on the production times were not calculated because personnel records were not include the personnel performances. The effects of wrong production plans and delivery on the capacity and the costs were not calculated. The capacity changes of the production in day aren't determined.The method which is followed for optimization is presented under below:1) The series were created based on the data which was taken from shift reports of machines in the period of last six months. Correlation coefficient method was used to confirm the reliability of the series used. Regression analyses of the machines in the printing company were made based on the series, and regression lines were drawn by SPSS software then regression equations of each machine were written. Regression equations were used for forecasting the production times of the machines for new orders. 2) Technical specifications of each machine were determined. Then, constraints were specified for each production center. According to constraints, it was determined which specifications of an order should be needed for calculation.3) According to machine capacities and the specifications of orders. It was determined that which machine would produce which order. The production times of each machine were calculated by using the regression equations. Then hourly costs of the machines were calculated and all data were written on the main table. All these steps were shown on a flow chart in the fifth part. These calculations were made for 31 orders by using Excel macros on computer. But one sample order was calculated manually for making the calculations more clear.4) After the calculations, machines which have the minimum hourly cost and minimum production time were chosen for each order. Then, optimization charts were drawn for each department to test existence of the optimization.In the seventh part, there were critics about the optimization system and there were some recommendations to increase the system productivity

Comparison of continuous wave and cold lateral condensation filling techniques in 3D printed simulated C-shape canals instrumented with Reciproc Blue or Hyflex EDM

AimTo compare the efficiency of continuous wave obturation and cold lateral condensation techniques and filling time in C-shape canals of 3-dimensional (3D)-printed resin teeth shaped with Reciproc Blue (VDW) or Hyflex EDM (Coltene/Whaledent).MethodologyOne tooth with C1-type orifice and root canal morphology and one with C2-type orifice and C2-C3 root canal morphology were selected based on CBCT. Two replicas of selected teeth were manufactured with a 3D-printer and their canals were instrumented with Reciproc Blue or Hyflex EDM. These 4 instrumented replicas were scanned with CBCT. Identical 10 replicas of each group (total of 40) were produced using a 3D-printer and randomly divided into 2 groups (n = 5), root filled with either continuous wave obturation (CW) or cold lateral condensation (LC). Horizontal cross-sections of C1-type were made at 2, 4, 6, 8 mm and C2-type at 2, 4, 6 mm from the apical foramen. Gutta-percha, sealer and void areas were evaluated with image analysis sofware. Data were analysed using nonparametric Kruskal-Wallis and Mann Whitney-U tests and the Factorial ANOVA was used for interaction effects. Time required to fill canals was evaluated using the Mann-Whitney U test.ResultsFor C1-type, LC had more gutta-percha and less sealer compared to CW in 2-mm sections (p0.05). In both C-types, there was no significant difference in the percentages of gutta-percha, sealer and voids between Reciproc Blue and Hyflex EDM-shaped groups at any level (p>0.05). Time spent for the LC technique and filling C1-type was significantly longer than when using the CW technique and filling C2-type (pConclusionsContinuous wave obturation was more effective than lateral condensation in both C1- and C2-type, except for the apical 2 mm section of C1-type, suggesting the need for a modified CW technique