A Combine On-Line Acoustic Flowmeter and Fluorocarbon Coolant Mixture Analyzer for The ATLAS Silicon Tracker

An upgrade to the ATLAS silicon tracker cooling control system may require a change from C3F8 (octafluoro-propane) to a blend containing 10-30% of C2F6 (hexafluoro-ethane) to reduce the evaporation temperature and better protect the silicon from cumulative radiation damage with increasing LHC luminosity. Central to this upgrade is a new acoustic instrument for the real-time measurement of the C3F8/C2F6 mixture ratio and flow. The instrument and its Supervisory, Control and Data Acquisition (SCADA) software are described in this paper. The instrument has demonstrated a resolution of 3.10-3 for C3F8/C2F6 mixtures with ~20%C2F6, and flow resolution of 2% of full scale for mass flows up to 30gs-1. In mixtures of widely-differing molecular weight (mw), higher mixture precision is possible: a sensitivity of < 5.10-4 to leaks of C3F8 into the ATLAS pixel detector nitrogen envelope (mw difference 160) has been seen. The instrument has many potential applications, including the analysis of mixtures of hydrocarbons, vapours for semi-conductor manufacture and anaesthesia

Development of a custom on-line ultrasonic vapour analyzer/flowmeter for the ATLAS inner detector, with application to gaseous tracking and Cherenkov detectors

Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom electronics, currently in use in the ATLAS inner detector, with numerous potential applications. The instrument has demonstrated ~0.3% mixture precision for C3F8/C2F6 mixtures and < 10-4 resolution for N2/C3F8 mixtures. Moderate and high flow versions of the instrument have demonstrated flow resolutions of +/- 2% F.S. for flows up to 250 l.min-1, and +/- 1.9% F.S. for linear flow velocities up to 15 ms-1; the latter flow approaching that expected in the vapour return of the thermosiphon fluorocarbon coolant recirculator being built for the ATLAS silicon tracker.Comment: Paper submitted to TWEPP2012; Topical Workshop on Electronics for Particle Physics, Oxford, UK, September 17-21, 2012. KEYWORDS: Sonar; Saturated fluorocarbons; Flowmetry; Sound velocity, Gas mixture analysis. 8 pages, 7 figure

Applications and perspectives of ultrasonic multi-gas analysis with simultaneous flowmetry

We have developed ultrasonic instrumentation for simultaneous flow and composition measurement in a variety of gas mixtures. Flow and composition are respectively derived from measurements of the difference and average of sound transit times in opposite directions in a flowing process gas. We have developed a sound velocity-based algorithm to compensate for the effects of additional gases, allowing the concentrations of a pair of gases of primary interest to be acoustically measured on top of a varying baseline from ‘third party’ gases whose concentrations in the multi-gas mixture are measured by other means. Several instruments are used in the CERN ATLAS experiment. Three monitor C3F8, (R218), and CO2 coolant leaks into N2-purged environmental envelopes. Precision in molar concentration of better than 2 × 10−5 is routinely seen in mixtures of C3F8 in N2 in the presence of varying known concentrations of CO2. Further instruments monitor air ingress and C3F8 vapor flow (at high mass flows around 1.1 kg s−1) in the 60 kW thermosiphon C3F8 evaporative cooling recirculator. This instrumentation and analysis technique, targeting binary pairs of gases of interest in multi-gas mixtures, is promising for mixtures of anesthetic gases, particularly in the developing area of xenon anesthesia.</jats:p

Optimization of Ribosome Structure and Function by rRNA Base Modification

BACKGROUND: Translating mRNA sequences into functional proteins is a fundamental process necessary for the viability of organisms throughout all kingdoms of life. The ribosome carries out this process with a delicate balance between speed and accuracy. This work investigates how ribosome structure and function are affected by rRNA base modification. The prevailing view is that rRNA base modifications serve to fine tune ribosome structure and function. METHODOLOGY/PRINCIPAL FINDINGS: To test this hypothesis, yeast strains deficient in rRNA modifications in the ribosomal peptidyltransferase center were monitored for changes in and translational fidelity. These studies revealed allele-specific sensitivity to translational inhibitors, changes in reading frame maintenance, nonsense suppression and aa-tRNA selection. Ribosomes isolated from two mutants with the most pronounced phenotypic changes had increased affinities for aa-tRNA, and surprisingly, increased rates of peptidyltransfer as monitored by the puromycin assay. rRNA chemical analyses of one of these mutants identified structural changes in five specific bases associated with the ribosomal A-site. CONCLUSIONS/SIGNIFICANCE: Together, the data suggest that modification of these bases fine tune the structure of the A-site region of the large subunit so as to assure correct positioning of critical rRNA bases involved in aa-tRNA accommodation into the PTC, of the eEF-1A•aa-tRNA•GTP ternary complex with the GTPase associated center, and of the aa-tRNA in the A-site. These findings represent a direct demonstration in support of the prevailing hypothesis that rRNA modifications serve to optimize rRNA structure for production of accurate and efficient ribosomes

Оценка качества жизни пациентов после хирургического лечения рака почки

Background. Restoring the quality of life of patients to a level comparable to that of practically healthy people is the most important task of medicine in general. At this stage of development of science, the main goal in the treatment of malignant diseases remains the preservation of life. However, now in oncological practice, methods whose potential allows not only to preserve life as such, but also to ensure the high quality of this life in all its manifestations, are acquiring greater and greater significance.The objective of the study is to compare the quality of life of persons with localized kidney cancer in the early and late periods after surgical treatment by radical nephroectomy and laparoscopic resection of renal tissue.Materials and methods. A questionnaire survey using SF-36 (Short Form-36), designed for a comprehensive assessment of the quality of life associated with health.Results. The quality of life of patients with localized kidney cancer before treatment is reduced due to a number of physical and mental nature, limiting labor, domestic and social activity and causing a feeling of dissatisfaction with their lives in general. These problems are disorders of physical, social and emotional functioning, physical pain, deterioration of general and mental health, limitations of role functioning due to physical and emotional state. After surgical treatment with laparoscopic resection, complete satisfaction of patients with the quality of their life was achieved during the first 1–3 postoperative months; after radical nephroectomy – not earlier than 1–3 years.Conclusion. One of the advantages of laparoscopic resection over radical nephroectomy is a higher quality of life of patients in the early and late periods after the intervention.Введение. Восстановление качества жизни пациентов до уровня, сопоставимого с таковым у практически здоровых лиц, – важнейшая задача медицины в целом. На данном этапе развития науки основной целью при лечении злокачественных заболеваний остается сохранение жизни. Однако уже сейчас в онкологической практике все большую значимость приобретают методы, позволяющие не только сохранить жизнь, но и обеспечить высокое ее качество во всех проявлениях.Цель исследования – сравнение качества жизни пациентов с локализованным раком почки в раннем и отдаленном периодах после радикальной нефрэктомии и лапароскопической резекции ренальной ткани.Материалы и методы. Выполняли анкетирование с помощью опросника SF-36 (Short Form-36), предназначенного для комплексной оценки качества жизни, связанного с состоянием здоровья.Результаты. Качество жизни больных локализованным раком почки до начала лечения снижено за счет ряда проблем физического и ментального характера, ограничивающих трудовую, бытовую и социальную активность и вызывающих чувство неудовлетворенности своей жизнью в целом. Этими проблемами стали нарушения физического, социального и эмоционального функционирования, телесная боль, ухудшение общего и психического здоровья, ограничения ролевого функционирования, обусловленные физическим и эмоциональным состоянием. После хирургического лечения методом лапароскопической резекции почки полная удовлетворенность пациентов качеством своей жизни достигалась в течение первых 1–3 мес после операции; методом радикальной нефрэктомии – не ранее чем через 1–3 года.Заключение. Одним из преимуществ лапароскопической резекции почки перед радикальной нефрэктомией является более высокое качество жизни пациентов в раннем и отдаленном периодах после вмешательства

Молекулярно-генетические и цитогенетические характеристики спорадического рака почки: обзор литературы

To compile this literature review, we studied at least 100 publications devoted to the genetic basis of clear cell, papillary, and chromophobic sporadic kidney cancer pathogenesis. Each of them considered the role of somatic gene and chromosomal mutations in the initiation, promotion, and tumor progression of sporadic renal cell carcinoma, emphasized the importance of determining the mutagenic profile of renal cell carcinoma for the future fate of patients.Источниками для данного обзора литературы послужили не менее 100 публикаций, посвященных генетическим основам патогенеза светлоклеточного, папиллярного и хромофобного спорадического рака почки, в которых рассматривалась роль соматических генных и хромосомных мутаций в инициации, промоции и опухолевой прогрессии спорадического почечно-клеточного рака и подчеркивалась значимость определения мутагенного профиля почечно-клеточного рака для прогноза для пациентов