47 research outputs found
Realizing the redefined kelvin: Extending the life of the ITS-90
Following the redefinition of the kelvin [1,2], the user is presented with a more nuanced traceability choice through the mise en pratique for the definition of the kelvin (MeP-K-19) [3]. Here we describe research to address several present and potential shortcomings with the current main dissemination route, namely using the International Temperature Scale of 1990 (ITS-90) [4]. The ITS-90 has served the global temperature measurement community well, providing reliable, low uncertainty traceability for over 30 years. However, there are some potentially life-limiting issues for the ITS-90. Among these are the impact of the main types (1 and 3) of non-uniqueness which currently limit the uncertainties achievable with the ITS-90, and the need to identify a possible alternative to the mercury triple point (a key fixed point of the ITS-90) whose use could be banned by an international treaty [5]. Progress in addressing these problems will be described through: • New determinations of Type 3 non-uniqueness have been undertaken in the range -189 °C to 156 °C; • A comprehensive evaluation of Type 1 non-uniqueness on a large number of Standard Platinum Resistance Thermometers (SPRTs) across multiple regions; • Comparison of high temperature SPRTs in pressure-controlled heat pipes to characterize Type 3 non-uniqueness between 660.323 °C and 961.78 °C; • New designs of CO2 and SF6 cells for use with long-stem SPRTs. These have been improved by using purer gases and more stable and uniform temperature-controlled baths, and by the development of a flexible set-up that can accommodate both capsule and long-stem SPRTs. The effect of replacing mercury on the ITS-90 interpolating equations and uncertainty propagation is also being investigated. References [1] https://www.bipm.org/en/publications/si-brochure [2] G. Machin, The kelvin redefined, Meas. Sci. Technol. 29 022001 (11pp) (2018) https://doi.org/10.1088/1361-6501/aa9ddb [3] B. Fellmuth, J. Fischer, G. Machin, S. Picard, P.P.M. Steur, O. Tamura, D.R. White, H. Yoon, The kelvin redefinition and its mise en pratique, Phil. Trans R. Soc. A., 374 (2064) (2016), p. 20150037, https://doi.org/10.1098/rsta.2015.0037 [4] Real-K project website: https://real-k.aalto.fi/ [5] The use of mercury, even for scientific purposes, could be severely restricted or even banned by international convention (UN Minamata Convention on Mercury which introduces controls over a myriad of products containing mercury)
Speeding-up Scientific Knowledge Transfer and Improvement of Capabilities of emerging European National Metrology Institutes and Designated Institutes in the field of thermal measurements: Benefits and Impacts
Within the frame of a European project called Eura-Thermal, the general objective was to upgrade the regional metrological infrastructure (Bosnia & Herzegovina, Croatia, Ireland, Serbia...) with new capabilities, especially in the field of thermal measurements. This paper highlights the strategy used for improving in the short term, scientific knowledge transfer and the capabilities of different emerging institutes. Furthermore, as a main output, the impacts and benefit for Industry and for the end-users are also presented as examples. © 2018 Institute of Physics Publishing. All rights reserved.XXII World Congress of the International Measurement Confederation (IMEKO 2018
Visual Loss After Lumbar Discectomy Due to Cortical Infarction: Case Report
Postoperative vision loss associated with spine surgery is a well known, albeit very rare complication. Origin and pathogenetic mechanism of postoperative vision loss remain frequently unknown. Postoperative vision loss incidence after spinal surgery ranges from 0.028 to 0.2%. We report a 53 year-old woman in whom a partial visual loss in the right eye occurred two hours after lumbar spine surgery. Known comorbidities included arterial hypertension, diabetes mellitus type 2, and mild anemia. There was no significant problem during lumbar spine surgery in prone position. Dural tear did not occur. The operation time was 50 minutes. We have highlighted the possible mechanism of the unusual complication and how to prevent of such conditions
SENSORY INTERACTION BALANCE AND LIMITS OF STABILITY IN NECK PAIN : COMPARISON OF TRAUMATIC AND NON-TRAUMATIC PATIENTS
Purpose: A variety of sensory-motor changes are reported in both the traumatic and non-traumatic neck pain. However, it is still unclear whether there is a significant difference between individuals with traumatic neck pain and those with non-traumatic in terms of postural control. The aim of this cross-sectional study was to investigate whether there was a difference between individuals with traumatic pain and non -traumatic neck pain in terms of postural control and disability. Material and Methods: Ninety-two patients with chronic neck pain were grouped according to the onset of pain. Clinical test of sensory interaction balance (CTSIB) and limits of stability (LOS) test were used for postural control assessment. The Numeric Rating Scale and Neck Pain Disability Index (NPDI) were used to measure pain intensity and disability, respectively. Mann-Whitney U test was used to compare groups. Results: There were no significant differences between groups in terms of LOS, CTSIB and NPDI scores (p>0.05). Conclusion: The results of this study suggest that postural control and disability do not differ between patients with traumatic and non-traumatic neck pain. Therefore, from a clinical perspective, postural control and disability should be evaluated without considering trauma history in patients with neck pain
Relationship between grip strength and sensory interaction in patients with cervical disc herniation
Comparisons of postural control, proprioception, muscle strength, pain and disability between individuals with acute, subacute and chronic low back pain.
Difficult Diagnosis of an Atypical Amyotrophic Lateral Sclerosis Case with Foot-drop
Amyotrophic lateral sclerosis (ALS) with atypical symptoms poses a diagnostic challenge to clinicians, frequently resulting in delayed diagnosis. The patient reported here presented with unexplained lower extremity pain and weakness and he was investigated for 8 months, with an extensive work-up, including several EMG studies, especially to rule out canal stenosis processes, before a diagnosis of ALS could be made, largely on the basis of upper and lower motor neurons. Differential diagnosis with motor axonal neuropathies may be particularly difficult. EMG is an essential tool for the early diagnosis of ALS, which increases potential benefit s of therapeutic interventions. In motor neuron diseases/amyotrophic lateral sclerosis (ALS), electrodiagnostic techniques are essential in supporting the diagnosis and excluding other conditions that clinically resemble ALS. In case of clinical suspicion in patients with recurrent EMG thinning should be done to reach the definite diagnosis