Analisis Logam Timbal (Pb) Dan Konsentrasi Klorofil Pada Alga Padina Australis Hauck Dari Perairan Teluk Totok Dan Perairan Blongko, Provinsi Sulawesi Utara

Penelitian ini dilakukan dengan tujuan untuk menganalisis kandungan logam timbal (Pb) pada air, sedimen, dan thallus alga serta mengetahui konsentrasi pigmen klorofil pada alga Padina australis Hauck yang terdapat di Perairan Teluk Totok dan Perairan Blongko. Perairan Teluk Totok merupakan perairan tempat buangan limbah pertambangan, sedangkan Perairan Blongko adalah perairan yang relatif bersih dan termasuk dalam Daerah Perlindungan Laut. Analisis logam timbal (Pb) pada air, sedimen, dan thallus alga berdasarkan metode standar American Public Health Association (APHA) dan analisis pigmen klorofil total yaitu dalam aseton 95% dengan menggunakan spektrofotometer. Hasil penelitian menunjukkan bahwa analisis konsentrasi logam timbal (Pb) telah terdeteksi pada dua perairan, di sedimen Perairan Blongko sebesar 4,4 ppm dan Perairan Teluk Totok keberadaan logam timbal lima kali lebih banyak yaitu sebesar 22,6 ppm. Analisis logam pada Thallus alga P.australis Hauck di Perairan Teluk Totok sebesar 3,8 ppm, lebih tinggi dibandingkan dengan konsentrasi timbal (Pb) dalam thallus P. australis Hauck dari Perairan Blongko yaitu sebesar 1,1 ppm. Nilai rata-rata konsentrasi pigmen klorofil a dan c di Perairan Teluk Totok adalah 19.073 g/ml klorofil a dan 1.275 g/ml klorofil c lebih tinggi dibandingkan dengan nilai rata-rata pigmen klorofil di Perairan Blongko yaitu 7.296 g/ml klorofil a dan 0.975 klorofil c. Perairan yang telah terkontaminasi logam, alga yang hidup didalamnya mampu melakukan proses fotosintesis untuk mempertahankan hidup

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

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

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