PHIP - a novel candidate breast cancer susceptibility locus on 6q14.1

Most non-BRCA1/2 breast cancer families have no identified genetic cause. We used linkage and haplotype analyses in familial and sporadic breast cancer cases to identify a susceptibility locus on chromosome 6q. Two independent genome-wide linkage analysis studies suggested a 3 Mb locus on chromosome 6q and two unrelated Swedish families with a LOD > 2 together seemed to share a haplotype in 6q14.1. We hypothesized that this region harbored a rare high-risk founder allele contributing to breast cancer in these two families. Sequencing of DNA and RNA from the two families did not detect any pathogenic mutations. Finally, 29 SNPs in the region were analyzed in 44,214 cases and 43,532 controls from BCAC, and the original haplotypes in the two families were suggested as low-risk alleles for European and Swedish women specifically. There was also some support for one additional independent moderate-risk allele in Swedish familial samples. The results were consistent with our previous findings in familial breast cancer and supported a breast cancer susceptibility locus at 6q14.1 around the PHIP gene.Peer reviewe

Investigation of phosphate coating formation by electrochemical impedance spectroscopy

In this investiAation, an attempt has been made to use electrochemical impedance spectroscopy as a tool for monitoring the phosphate coating formation, especially the involvment of hase metal in the coating fornlation. Results of the studies have been presented in the foml of Nyquist plot.. of various immersion time which shows a depressed semicircle and the diameter and degree of depression increase with time. Charge transfer resistance and the int~rfacial capacitance of steel in phosphatin~ solution are parameters of impedance study which helps in assessing and optimizing the conditions of phosphating. The result.. also show that presence of crystal refiner and/or accelerator accelerate the base metal dissolution at the initial stJlge of coating formation and the crystal refiner modifies the coating properties hy lowering tbe porosity by redissolution and deposition

Copper-manganese alloy for marine environment

Studies have been made on the behaviour of copper-manganese alloys, with and without addition of other elements in synthetic sea water, using potentiostatic technique. It is found that 70:30:Cu:Mn alloy hassuperior corrosion resistance probably because of the homogeneous micro-structure of the alloy. Addition of misch metal further improves corrosion resistance. The corrosion rate values were found to decrease in the following order: 80120: CuIMn, copper, 70130: CuIMn and CuIMn misch metal. The anodic Tafel constant (b,) is found to be 75 * 5 mvldecade, for copper and its alloys. Addition of manganese to copper shifts the open circuit potential in cathodic direction. It also marginally increases the hardness

Studies on manganese phosphating of steel

A new manganese phosphating bath which produces coating relatively at lower temperature within a reasonable time by the use of chemical accelerators bas been developed. Bath formulation and operating conditions have been optimized by coating weight determinations. Corrosion resistance property of the resultant coatings has been evaluated in 3% NaCI by electrochemical methods such as potentiodynamic polarisation, linear polarisation and impedance measurements. Results of the electrochemical techniques have heen complemented by salt spray, humidity and immersion tests. Porosity coatin~ has also been studied. Results show that the newer manganese phosphate bath gives good coatin~ at 353 K within 30 minutes. Addition of nitrates of various metals as accelerator produces thicker coatin~. Corrosion studies have shown that the corrosion resistance of the resultant coatin~ are much superior than the conventional coating;

Corrosion inhibition effect of tetramines for mild steel in 1M HCl

In this investigation, attempts have been made to study the inhibitive effect of triethylene tetramine (TETA) and hexamethylene tetramine (HMTA) for mild steel in 1 M hydrochloric acid in the concentration range of 10�6 to 10�2 M by weight loss, DC polarization methods and AC impedance spectroscopy. Results indicate that the addition of tetramines to the acid reduce the rate of metal attack. For both the amines, inhibition efficiency increases with the concentration of amine. The inhibition efficiency of the hexamethylene tetramine is less when compared to that of triethylene tetramine

Study of the zinc phosphate coating formation on steel impedance spectroscopy

Zinc phosphating of steel is a pre-treatment process used to improve the adhesion of the overcoats and under film corrosion resistance. In this investigation, an attempt has been made to use impedance spectroscopy as a tool for monitoring the phosphate coating formation on steel at OCP by applying an a.c.signal of 20 mV in the frequency range of 10 kHz to 1 Hz as a function of time. The impedance results have been complemented by the potential-time measurements. Results showed depressed semi-circles in the Nyquist plots, the diameter and depression of such capacitive loops increases with time of immersio

Corrosion behaviour of mild steel in sulphuric acid- Effect of halides

The effect of halide ions on the corrosion behavior of mild steel in sulphuric acid medium was studied. Weight loss and polarization studies were carried out in 1 M sulphuric acid and at various concentration of the halide ions (chloride, bromide and iodide). The results revealed that corrosion of mild steel is more in acid medium without halide ions. Halide ions reduce the rate of corrosion and the inhibition efficiency is found to be in the order iodide > bromide > chlorid

Effect of divalent cations in low zinc ambient temperature phosphating bath

A new zinc phosphating bath, which produces coatings at relatively lower temperatures within a reasonable time by using of chemical accelerators has been devised. Improvement of the bath performance by the addition of divalent cations like calcium, manganese and magnesium has been studied. Bath formulation and operting conditions have been optimized by coating weight determinations. Corrosion resistance property of the resultant coatings has been evaluated in 1000 ppm Cl- by electrochemical methods such as potentiodynamic polarization and impedance measurements. Results of the electrochemical techniques have been complemented by salt spray, humidity and immersion tests. Porosity and roughness of the coatings have also been studied. Results show that the phosphating bath with manganese addition gives good coatings within 30 mins. Studies have shown that the corrosion resistance of the resultant coatings are much superior than the conventional coating

Voltage noise measurements during staining of 6061 aluminium alloy exposed to humid atmospheres

Electrochemical noise generation during staining of 6061 aluminium alloy exposed to 60 to 100% RH at 323 K has been measured. The noise power values (V2) were obtained from the auto correlation of voltage time data. On exposure of aluminium alloy to 80 to 100% RH, considerable staining have been observed. During staining the noise power values were found to increase from 10-6 (V2) to 10-4 (V2) and a considerable weight gain was also observed. However, on exposure of aluminium alloy to 60% RH no staining was observed and the noise power value remained around 10-8 (V2). After passivation treatment of aluminium alloy in 50% HNO3 or with chromate treatment the noise power values remained at a low level of 10-8 (V2) till the protective power of the coating remained unaffecte

Corrosion behaviour of Ti6Al4V and duplex stainless steel (UNS 31803) in synthetic bio-fluids

Compares the corrosion behaviour of Ti6Al4V titanium alloy, a conventional duplex stainless steel (UNS 31803) ans AISI 304 austenitic stainless steel in synthetic biofluids using electrochemical techniques and comments on the suitability of DSS for use in biomedical applications. Finds that the general corrosion resistance of duplex stainless steels is slightly inferior to that of austenitic stainless steel and titanium alloy; duplex stainless steel does not show any sign of pitting when exposed to synthetic biofluids and exhibits excellent resistance to localised corrosion on par with that of titanium alloy. Concludes that duplex stainless steels are one of the best alternates to titanium alloy