X-Ray Repair Cross-Complementing Group 1 (XRCC1) Genetic Polymorphisms and Risk of Childhood Acute Lymphoblastic Leukemia: A Meta-Analysis

Background: Recently, there have been a number of studies on the association between XRCC1 polymorphisms and childhood acute lymphoblastic leukemia (ALL) risk. However, the results of previous reports are inconsistent. Thus, we performed a meta-analysis to clarify the effects of XRCC1 variants on childhood ALL risk. Methods: A meta-analysis was performed to examine the association between XRCC1 polymorphisms (Arg399Gln, Arg194Trp, and Arg280His) and childhood ALL risk. We critically reviewed 7 studies with a total of 880 cases and 1311 controls for Arg399Gln polymorphism, 3 studies with a total of 345 cases and 554 controls for Arg280His polymorphism, and 6 studies with a total of 783 cases and 1180 controls for Arg194Trp polymorphism, respectively. Odds ratio (OR) and its 95% confidence interval (CI) were used. Results: Significant association between XRCC1 Arg399Gln polymorphism and childhood ALL risk was observed in total population analyses (OR additive model = 1.501, 95 % CI 1.112–2.026, P OR = 0.008; OR dominant model = 1.316, 95 % CI = 1.104–1.569, POR = 0.002) and Asian subgroup analyses (ORadditive model = 2.338, 95%CI = 1.254–4.359, POR = 0.008; ORdominant model = 2.108, 95%CI = 1.498–2.967, POR = 0.000). No association was detected in Caucasians, Metizo and mixed populations. Ethnicity was considered as a significant source of heterogeneity in the meta-regression model. For the other two XRCC1 polymorphisms, no association with childhood ALL risk was found

EKOLOJI

In this study, a new wall plaster product was generated using 0-5% perlite, 0-2.5% waste paper and 3.5-17.7% waste calcined borax. The optimum ratios for the additives were 3% perlite, 1.5% waste paper and 7.1% waste calcined borax. The new plaster was subjected to mechanical strength and thermal transmittance measurements using TS 825 and TS 12808-3 Turkish standards. Under optimal mixing ratios, the plaster had a thermal conductivity of 0.17 W/m(2)K and a mechanical strength (bending) of 61.44 kg/cm(2) 2K. V. The required standards by TSE 825 are 0.13 W/m(2)K the new product was compared with the existing plasters in the market, it was observed that thermal transmittance and mechanical strength were both increased by 26% and 31%, respectively. Thus, a new environmental-friendly wall plaster product was produced

Theory and applications of microwave energy in communition

Thermal expansion of the selectively heated minerals offers the potential to further liberate the ore minerals from the gangue at larger particle sizes [1]. Cleaner liberation of the ore mineral at a larger particle size would reduce the grinding energy requirements as well as improve the concentrate grade and metal recovery after beneficiation. Microwaves used in comminution, including crushing and grinding processes, have the potential to reduce the required energy. The applications of microwave to mineral processing include drying of coal, recovery of gold from low grade ores and tailings, extraction of rare earth elements, the retorting of soil shale end smelting of metals. Energy consumed in comminution can be as high as 50-70% of the total process energy [2, 3 & 4]. If full-scale application of microwave technology can be accomplished, the addition and operation of a microwave could be an easy and efficient retrograde to reduce the mill power requirements by 25%. In this paper, it is shown that microwave energy is capable of inducing thermal stress cracking to decrease the energy requirements of grinding and leading to possible new applications for mining and ceramics industries

Effect of CaO on thermomechanical behavior of SiC based self-flowing castables

In this study the use of hydratable alumina binder (Alcoa) instead of Calcium Aluminate (CA) cement as binder in the production of SiC based self-flowing castable has been investigated. Spent SiC particles were classified into different fractions following crushing and grinding operations and have been utilized as aggregate. Tabular alumina, calcined monodipersed alumina, and hydratable alumina/CA cement were used as binder matrix. Anorthite (CaO.Al 2O3.2SiO2) a gehlenithe (2CaO.Al 2O3.2SiO2) phases were formed according to the CaO-Al2O3-SiO2 three phase diagram. Molten phase negatively affects refractoriness of the materials. For that reason, by using hydratable alumina instead of CA cement mullite binder was created. Mullite was studied by SEM. In addition to CA cement supplementary samples, molten phase produced with CaO lessened the value of the hot modulus of rupture (HMOR). Hydratable alumina binder added samples at 1450°C, however amplified the values of HMOR. It was concluded that the refractories acquired can be used as kiln furniture for porcelain sector

Electro-deposition parameters of boron carbonitride (bcn) from borax pentahydrate (NA2B4O7•5H2O)

The primary objective of this research is the fabrication of boron end products from boron derivatives by electro-deposition as powder or coating. The production of boron carbonitride is achieved by electro-deposition at low temperatures without carbon dioxide emission, regardless of sintering and thermal treatment. The extensive usage of boron is aimed and should be accomplished by application of electro-deposition method for boron carbonitride fabrication

Effect of CaO on thermomechanical behavior of SiC based self-flowing castables

In this study the use of hydratable alumina binder (Alcoa) instead of Calcium Aluminate (CA) cement as binder in the production of SiC based self-flowing castable has been investigated. Spent SiC particles were classified into different fractions following crushing and grinding operations and have been utilized as aggregate. Tabular alumina, calcined monodipersed alumina, and hydratable alumina/CA cement were used as binder matrix. Anorthite (CaO.Al2O3.2SiO(2)) a gehlenithe (2CaO.Al2O3.2SiO(2)) phases were formed according to the CaO-Al2O3-SiO2 three phase diagram. Molten phase negatively affects refractoriness of the materials. For that reason, by using hydratable alumina instead of CA cement mullite binder was created. Mullite was studied by SEM. In addition to CA cement supplementary samples, molten phase produced with CaO lessened the value of the hot modulus of rupture (HMOR). Hydratable alumina binder added samples at 1450 degreesC, however amplified the values of HMOR. It was concluded that the refractories acquired can be used as kiln furniture for porcelain sector

A feasibility investigation of Akseki boehmite ore for refractory industry

Turkey is considered poor in bauxite production due to high iron content of its reserves and thus, imports most of its refractory bauxite needed. In this study, a new processing method of a refractory bauxite ore was investigated. A refractory bauxite ore boehmite from Akseki, Turkey, containing an average of 12% Fe2O3, was successfully reduced to about 1% with HCl acid leaching method. This study shows a method of processing for this particular ore. This study also introduces a new approach, called an ellipse model, for the feasibility of processing stages

Production cost index for ceramic raw materials in Turkish mining sector

Variation in prices continuously makes it hard to estimate the prices for the engineers involved in project preparation. A method of providing beginning price estimation is to examine a similar fulfilled project cost. As the cost values refer to earlier period years, these values ought to be updated. A cost index is the most appropriate method to revise the cost values referring to the previous years. Thus, the ratio of varying cost and income that is required to investment analysis could be practically estimated

Upgrading schemes for boron minerals through calcination

Despite its importance in various diverse industries, research on beneficiation strategies of boron minerals has not received enough attention. Boron minerals are primarily upgraded by wet processing methods. However, severe environmental constrains have accelerated the development of dry processing techniques such as calcination. Interestingly, the boron minerals colemanite, ulexite and borax undergo decrepitation, shrinkage and expansion, respectively, upon heat treatment. Each mineral then requires a different beneficiation scheme. In this study, laboratory and pilot-plant studies conducted in our laboratories on the calcination of bet-on minerals ale briefly reviewed and their implications to commercial operations are discussed