Board examination for anatomical pathology in Switzerland: two intense days to verify professional competence

About 15years ago, the Swiss Society of Pathology has developed and implemented a board examination in anatomical pathology. We describe herein the contents covered by this 2-day exam (autopsy pathology, cytology, histopathology, molecular pathology, and basic knowledge about mechanisms of disease) and its exact modalities, sketch a brief history of the exam, and finish with a concise discussion about the possible objectives and putative benefits weighed against the hardship that it imposes on the candidate

Alignment of the CMS tracker with LHC and cosmic ray data

© CERN 2014 for the benefit of the CMS collaboration, published under the terms of the Creative Commons Attribution 3.0 License by IOP Publishing Ltd and Sissa Medialab srl. Any further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation and DOI.The central component of the CMS detector is the largest silicon tracker ever built. The precise alignment of this complex device is a formidable challenge, and only achievable with a significant extension of the technologies routinely used for tracking detectors in the past. This article describes the full-scale alignment procedure as it is used during LHC operations. Among the specific features of the method are the simultaneous determination of up to 200 000 alignment parameters with tracks, the measurement of individual sensor curvature parameters, the control of systematic misalignment effects, and the implementation of the whole procedure in a multi-processor environment for high execution speed. Overall, the achieved statistical accuracy on the module alignment is found to be significantly better than 10μm

Oxidation of Antibacterial Compounds by Ozone and Hydroxyl Radical: Elimination of Biological Activity during Aqueous Ozonation Processes

A wide variety of antibacterial compounds is rapidly oxidized by O-3 and hydroxyl radical ((OH)-O-center dot) during aqueous ozonation. Quantitative microbiological assays have been developed here or adapted from existing methods and utilized to measure the resulting changes in antibacterial potencies during O-3 and (OH)-O-center dot treatment of 13 antibacterial molecules (roxithromycin, azithromycin, tylosin, ciprofloxacin, enrofloxacin, penicillin G, cephalexin, sulfamethoxazole,trimethoprim, lincomycin, tetracycline, vancomycin, and amikacin) from 9 structural classes (macrolides, fluoroquinolones, beta-lactams, sulfonamides, dihydrofolate reductase inhibitors, lincosamides, tetracyclines, glycopeptides, and aminoglycosides), as well as the biocide triclosan. Potency measurements were determined from dose-response relationships obtained by exposing Escherichia coli or Bacillus subtilis reference strains to treated samples of each antibacterial compound via broth micro- or macrodilution assays and related to the measured residual concentrations of parent antibacterial in each sample. Data obtained from these experiments show that O-3 and (OH)-O-center dot reactions lead in nearly all cases to stoichiometric elimination of antibacterial activity (i.e., loss of 1 mole equivalent of potency per mole of parent compound consumed). The beta-lactams penicillin G (PG) and cephalexin (CP) represent the only clear exceptions, as bioassay measurements indicate that biologically active products may be formed in the reactions of these two compounds with both O-3 and (OH)-O-center dot. The active product(s) generated in the direct reaction of O-3 with PG appear(s) to be recalcitrant to further transformation by O-3, though any biologically active products formed in the reactions of CP with O-3, or of either PG or CP with (OH)-O-center dot, are apparently deactivated by further reactions with O-3 or (OH)-O-center dot, respectively. Thus, with few exceptions, it can be expected that municipal wastewater ozonation will generally yield sufficient structural modification of antibacterial molecules to eliminate their antibacterial activities, whether oxidation results from selective reactions with O-3 or from relatively nonselective reactions with incidentally produced (OH)-O-center dot

Column studies to assess the effects of climate variables on redox processes during riverbank filtration

Riverbank filtration is an established technique used world-wide to produce clean drinking water in a reliable and cost-efficient way. This practice is, however, facing new challenges posed by climate change, as already observed during past heat waves with the local occurrence of anoxic conditions. In this study we investigated the effect of direct (temperature) and indirect (dissolved organic matter (DOM) concentration and composition, flow rate) climate change variables on redox processes (aerobic respiration, denitrification and Mn(III/IV)/Fe(III) reduction) by means of column experiments. Natural river water, modified river water and river water mixed with treated wastewater effluent were used as feed waters for the columns filled with natural sand from a river-infiltration system in Switzerland. Biodegradable dissolved organic matter was mainly removed immediately at the column inlet and particulate organic matter (POM) associated with the natural sand was the main electron donor for aerobic respiration throughout the column. Low infiltration rates (<= 0.01 m/h) enhanced the oxygen consumption leading to anoxic conditions. DOM consumption did not seem to be sensitive to temperature, although oxygen consumption (i.e., associated with POM degradation) showed a strong temperature dependence with an activation energy of similar to 70 kJmol(-1). Anoxic conditions developed at 30 degrees C with partial denitrification and formation of nitrite and ammonium. In absence of oxygen and nitrate, Mn(II) was mobilized at 20 degrees C, highlighting the importance of nitrate acting as a redox buffer under anoxic conditions preventing the reductive dissolution of Mn(III/IV)(hydr)oxides. Reductive dissolution of Fe(III)(hydr)oxides was not observed under these conditions. (C) 2014 Elsevier Ltd. All lights reserved

Mechanistic and kinetic evaluation of organic disinfection by-product and assimilable organic carbon (AOC) formation during the ozonation of drinking water

Ozonation of drinking water results in the formation of low molecular weight (LMW) organic by-products. These compounds are easily utilisable by microorganisms and can result in biological instability of the water. In this study, we have combined a novel bioassay for assessment of assimilable organic carbon (AOC) with the detection of selected organic acids, aldehydes and ketones to study organic by-product formation during ozonation. We have investigated the kinetic evolution of LMW compounds as a function of ozone exposure. A substantial fraction of the organic compounds formed immediately upon exposure to ozone and organic acids comprised 60-80% of the newly formed AOC. Based on experiments performed with and without hydroxyl radical scavengers, we concluded that direct ozone reactions were mainly responsible for the formation of small organic compounds. It was also demonstrated that the laboratory-scale experiments are adequate models to describe the formation of LMW organic compounds during ozonation in full-scale treatment of surface water. Thus, the kinetic and mechanistic information gained during the laboratory-scale experiments can be utilised for upscaling to full-scale water treatment plants. (c) 2006 Elsevier Ltd. All rights reserved

Process Control For Ozonation Systems: A Novel Real-Time Approach

For real-time control of ozonation processes in water works, a sequencing batch reactor was constructed to measure the ozone decay rate constant (k(O3)) in short time intervals of about 15 min. The batch reactor is filled during the production process, immediately after dissolving ozone in water by a static mixer. On the basis of k(O3) and the initial ozone concentration ([O-3](0)), and the experimentally determined ratio of the concentrations of (OH)-O-center dot radicals to ozone (R-ct), the degradation of micropollutants in ozone reactors (modeled as Continuously Stirred Tank Reactors - CSTRs) were calculated for compounds with known reaction rate constants with ozone and (OH)-O-center dot radicals. Calculated degradation of atrazine, iopromide, benzotriazole and acesulfame are in good agreement with measured data. For acesulfame the following rate constants were determined in this study at 20 C-o: reaction rate constant with ozone = 88 M(1)s(1), reaction rate constant with (OH)-O-center dot radical = 4.55x10(9) M(1)s(1). For the ozone reaction an activation energy of 35 kJ/mol was determined. Similarly to micropollutants, the relative inactivation of microorganisms (N/N-0) can be calculated based on the inactivation rate constant for ozone and if applicable the lag phase. The pI-value (=logN/N-0) was introduced and implemented in the process management system to calculate online the log inactivation of reference microorganisms such as B. subtilis spores. The system was tested for variation of pH (6.58.5), DOC (1.24.2 mg/L) flowrate 3.212 m(3)/h and temperature (5.79 C-o). Furthermore, a given pI-value, e.g. 1 for a 1-log inactivation of B. subtilis spores, can be set as control parameter in the process management system. The ozone gas flow is then adjusted until the set pI-value is reached. The process control concept was validated with B. subtilis spores. Generally, a good agreement was found between calculated and measured inactivation data. It was also demonstrated, that a constant ozone residual may lead to insufficient disinfection or overdosing of ozone. The new process control concept for ozonations based on onsite measurement of the ozone decay rate constant and the pI-value allows to assess disinfection and degradation processes quantitatively in real-time