Influence of indomethacin on lens regeneration in the newt notophthalmus viridescens

Following lentectomy newts were injected with indomethacin in a variety of carrier solutions at doses ranging from 1.2–120 mg/kg body weight every other day for 15–17 days. The results show that injection of this drug according to the regimen used has no significant effect on regeneration of the lens. The data suggest, but do not prove, that prostaglandins may not play a major role in the early phases of lens regeneration in the newt.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47503/1/427_2004_Article_BF00848434.pd

Operation and performance of the ATLAS semiconductor tracker

The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74±0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, δ-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations

A method for purifying Lu and Hf for analyses by MC-ICP-MS using TODGA resin

A two-stage method is presented to separate Lu and Hf from silicate rock and mineral samples digested by either flux melting or HF–HNO3 dissolution using TODGA resin from Eichrom Industries. A first-stage chemistry employs a 2-ml cation exchange column that separates the high-field-strength elements (HFSE) and rare-earth elements (REE) from the matrix. Hf–Zr and Yb–Lu are subsequently separated from the HFSE-REE concentrates on a second-stage 0.2-ml TODGA column. This method returns sufficiently pure cuts to overcome all atomic and molecular interferences as well as the detrimental effects of Ti on Hf fractionation associated with MC-ICP-MS. Boric acid serves two roles in this method: (1) it effectively breaks down fluorides formed in the dry-down step after HF–HNO3 digestions, thereby avoiding use of perchloric acid and/or multiple dry-down and re-dissolution steps, and (2) it is added to the loading solution of the second-stage chemistry to prevent formation of Hf-fluorides that would not be retained by TODGA resin. Using these methods, international rock standards BHVO-1 (processed by both flux melting and HF–HNO3 dissolution) and BCR-2 (processed by HF–HNO3 dissolution) yield 176Hf/177Hf and 176Lu/177Hf ratios that overlap with published values. Permutations of the basic method are presented for samples with significantly elevated LREE contents and for the separation of Lu and Hf from zircon