Synthesis and hyperpolarisation of eNOS substrates for quantification of NO production by 1H NMR spectroscopy

Hyperpolarization enhances the intensity of the NMR signals of a molecule, whose in vivo metabolic fate can be monitored by MRI with higher sensitivity. SABRE is a hyperpolarization technique that could potentially be used to image nitric oxide (NO) production in vivo. This would be very important, because NO dysregulation is involved in several pathologies, including cardiovascular ones. The nitric oxide synthase (NOS) pathway leads to NO production via conversion of l-arginine into l-citrulline. NO is a free radical gas with a short half-life in vivo (≈5s), therefore direct NO quantification is challenging. An indirect method - based on quantifying conversion of an l-Arg- to l-Cit-derivative by 1H NMR spectroscopy - is herein proposed. A small library of pyridyl containing l-Arg derivatives was designed and synthesised. In vitro tests showed that compounds 4a-j and 11a-c were better or equivalent substrates for the eNOS enzyme (NO2 - production=19-46μM) than native l-Arg (NO2 - production=25μM). Enzymatic conversion of l-Arg to l-Cit derivatives could be monitored by 1H NMR. The maximum hyperpolarization achieved by SABRE reached 870-fold NMR signal enhancement, which opens up exciting future perspectives of using these molecules as hyperpolarized MRI tracers in vivo

Results of coordinate measuring arms' accuracy testing

Na początku krótko opisano budowę ramienia pomiarowego w odniesieniu do głównych jego zespołów. Przedstawiono oprogramowanie pomiarowe PowerINSPECT oraz zaprezentowano element w postaci tzw. kostki szkoleniowej z zaznaczeniem parametrów, które podlegały badaniom. Artykuł zawiera syntetyczny opis procedury pomiarowej, wyniki pomiarów i ich interpretację.At first the construction of the measuring arm with reference to its main units was briefly described. The PowerINSPECT measurement software was presented. Also a part in the form of so called training cube with selected for tests parameters was presented. The article contains a synthetic description of the measurement procedure, measurement results and their interpretation

Systems for damaged car bodys measurements

Geometrical measurements of car bodies appear mainly in connection with post accident repair processes. They appear also independently in diagnostic measurements. Presentation of measuring systems is very actual in relation to a large number of car accidents. Diagnostic tests of repaired car body and restoring its nominal sizes are essential for safe traffic. The subject area is particularly interesting for service and repairing units e.g. tinsmith's workshops, but also for car experts. In the article, the methods of car body measurements will be characterized on the example of the use of simple telescopic gauges up to fully computerized electronic measuring systems. The examples of measuring card with basic points, being the nominal points’ coordinates, are presented as well as suggestions concerning the kinds of measuring tips ascribed to those points. Each card with basic points is characteristic only for a particular type of a car body. The examples of illustrations, with visible points on a car body where a prescribed measuring tip should be applied, are also shown. At the end an attempt of measurements' accuracy estimation will be presented on the example of one of electronic measuring devices

X-ray computed tomography for industrial tasks

W artykule przedstawiono najnowszą generację urządzeń pomiarowych wchodzących do przemysłu i jednostek badawczych, a mianowicie tomografię komputerową CT. Opisano istotę pomiarów tomograficznych, zasadę działania i budowę tomografów, ich funkcje i oprogramowanie. Następnie przedstawiono liczne przykłady zastosowań w wyznaczaniu wymiarów geometrycznych, zarówno w odniesieniu do modelu CAD, jak i tworzeniu modelu w zakresie inżynierii odwrotnej. Przedstawiono również przykłady wykrywania wad materiału w defektoskopii.This paper presents the latest generation of measuring devices being introduced into the industry and research units, namely, computed tomography CT. The essence of tomography measurements, principles of operation and construction of scanners, their functions and software are described. Then presents several examples of applications in determining the geometrical dimensions of both the CAD model and creating a model for reverse engineering are presented. It also presents examples of flaw detection in revealing of defects in the material

Advanced coordinate measurements in production engineering

Przedstawiono maszyny i urządzenia pomiarowe pracujące w technice pomiarów współrzędnościowych, które mogą być zastosowane bezpośrednio w otoczeniu produkcji. Zilustrowano je przykładami maszyn w postaci robotów i centrów pomiarowych oraz tzw. Ramion pomiarowych.CMM's and measuring equipments that can be used in embroilments of production are presented. They are illustrated by examples of robots, measuring centers and measuring arms

Trends in development of coordinate measuring techniques

Podjęta została próba przedstawienia tendencji w rozwoju współrzędnościowej techniki pomiarowej. Odniesiono się do kierunku rozwoju maszyn pomiarowych wskazując na ich rozwój osobno dla zastosowań przemysłowych oraz pod kątem wysokiej dokładności - do zastosowań laboratoryjnych. Scharakteryzowano rozwój optoelektronicznych inkrementalnych układów pomiarowych oraz głowic pomiarowych. Na końcu, w podsumowaniu, zwrócono uwagę na ewentualne kierunki rozwoju oprogramowań pomiarowych.A trial has been undertaken to present trends in development of coordinate measuring techniques. The direction of the development related to their use in industry and from the point of view of high accuracy in laboratory applications has been discussed. The development of incremental measuring systems and measuring heads have been characterized. Finally the attention has been paid to possible directions in the development of measuring software

Computed tomography in 3D geometrical measurements

Istota pomiarów tomograficznych opartych na promieniowaniu rentgenowskim X. Budowa tomografów - główne zespoły i ich funkcje. Kalibracja tomografów. Prezentacja modelu tomografu opracowanego w Instytucie Metrologii i Inżynierii Biomedycznej.Computed tomography (CT), after its dynamical development for medical requirements recently starts to appear in an area of industrial applications. It enables not only to determine dimensions of objects made of metal, plastics and different kinds of composed materials but also to defect internal defects of the material. This paper describes concepts of CT measurements. The main construction units of tomographs are characterized and the examples of tomographs of different firms and their applications are given. The accuracy and calibration problems are also shortly discussed. At the and the concepts of home - made computed tomograph for industrial applications are also presented

CT industrial tomographs - parameters, applications, test accuracy

Wyjaśniono zasadę budowy i działania tomografu komputerowego CT - wyszczególniono główne zespoły i ich funkcje. Zamieszczono przykład tomografu i jego parametry. Pokazano możiiwości pomiarowe tomografów, a na końcu zaprezentowano parametry charakteryzujące dokładność podając przykład wyznaczenia dokładności tomografu METROTOM za pomocą specjalnie zbudowanego wzorca.The principle of construction and operation of a CT scanner is explained. Major units and their functions are specified. The construction and operation of an X-ray tube as well as the positioning system associated with mounting of a measured object are described. The principle of construction and operation of a matrix (panel) of detectors is explained. Examples of scanners and their parameters are included. Measurement capabilities of tomographs, including options such as standard geometry of dimensions with respect to the CAD model or reverse engineering if the CAD model is not available, are shown. Also the possibility to capture material discontinuities, inclusions of impurities, bubbles, in terms of the so-called defectoscopy, is shown. Finally, the parameters characterizing the accuracy are presented. These parameters include: the parameter associated with the error of the length measurement - E, the parameters associated with the scanning error - PF, PS, the parameters defining the dimensions and material dependencies - GS, GF, GG, the parameter specifying the resolution - Dg. The parameters associated with the error of the length measurement are explained based on the accuracy verification for a METROTOM tomograph with the use of a specially built artefact

Comparison investigations of CMM accuracy tests by different length gauges

Przeprowadzono badania, mające na celu sprawdzenie możliwości zastosowania nowej metody sprawdzania dokładności współrzędnościowych maszyn pomiarowych (CMM) w odniesieniu do metody klasycznej. W nowej metodzie dokładność CMM określana jest na podstawie pomiaru przemieszczenia elementu optycznego wchodzącego zarazem w skład układu interferometru laserowego. Zastosowanie interferometru pozwala na sprawdzenie dokładności CMM na dowolnie długich odcinkach pomiarowych w przeciwieństwie do obecnie używanych wzorców końcowych tzn. płytek wzorcowych, których długość nie przekracza jednego metra.The conception of an accuracy test for Coordinate Measuring Machine with use of a laser interferometer is presented. In this method [1, 2] the CMM accuracy is evaluated basing on the displacement of an optics element (Fig. 1.) which is a part of the interferometer system. Interferometer allows checking the CMM accuracy along an unlimited distance in contrary to the most popular gauge blocks which are no longer than one meter. A cube corner fixed in the special adapter (Fig. 2.) was used as an artifact. Repeatability of measurements of the cube corner was checked on CMM ACCURA made by C.Zeiss manufacturer, CMM was equipped with a VAST Gold central head probe. The measurement results of the reference sphere and cube corner are shown in Fig. 3. The experiment results confirm that a cube corner can be used as the measurement artifact for coordinates measuring machines. It also works very well as a mirror in the interferometer system. The cube corner measurement repeatability (0.2 žm) is similar to that reached during measurements of the reference sphere (0.4 žm). The methods was also checked during the accuracy test for the ZEISS ACCURA CMM. The results are presented in Fig. 4. The differences between the measurements of the gauge block and cube corner change from -0.8 to 0.6 žm. In the future research it will be important to assess all factors which can influence the accuracy of this method during the CMM length measurement test

The accuracy of industrial computer tomography scanners in determining geometric dimensions

Zaprezentowano metodę w zakresie wyznaczania dokładności wymiarów geometrycznych przemysłowych tomografów komputerowych zgodnie z wytycznymi VDI/VDE 2630. Zaprezentowano propozycje sprawdzenia dokładności tomografu opartą na wzorcu składającym się z zestawu trzpieni z końcówkami kulistymi. Opisano wzorzec zaprojektowany i skonstruowany w Instytucie Metrologii i Inżynierii Biomedycznej Politechniki Warszawskiej. Wzorzec został wykalibrowany za pomocą współrzędnościowej maszyny pomiarowej ACCURA firmy C. Zeiss. Na podstawie uzyskanych danych pomiarowych wykonany został model CAD wzorca. Uzyskane podczas pomiarów tomograficznych chmury punktów zostały porównane z modelem CAD. Przeprowadzono analizę statystyczną uzyskanych wyników oraz sprawdzono podawaną przez producenta dokładność pomiarów geometrycznych tomografu komputerowego METROTOM 800.This paper presents the construction of a computer tomography scanner (CT). It discusses the principles of operation of CT. The parameters characterizing the accuracy are described. The proposed method for determining the geometric dimension accuracy of industrial computer tomography scanners according to VDI / VDE 2630 is discussed. The presented proposals can be used to verify the tomography scanner accuracy based on gauges consisting of a set of spherical stylus. A gauge to check the CT accuracy was designed and constructed at the Institute of Metrology and Biomedical Engineering, the Warsaw University of Technology. The gauge was calibrated using a coordinate measuring machine ACCURA 7 by C. Zeiss. Based on the measurement data a CAD model of the gauge was made. The measurement strategies were based on the CAD model. The point clouds for tomographic measurements were compared with the CAD model. The results of the two measuring devices were compared. Statistical analysis of the results was conducted. It showed statistically significant differences between the methods of measuring on the confidence level of 95%. It was also confirmed by the statistical parameters obtained for the both methods. The values of the range and standard deviations were approximately twice as high for the tomographic measurements. Also the accuracy specified by the manufacturer of CT METROTOM 800 was verified