EURAMET key comparison between INRiM and UME in Vickers hardness scales (HV1 - HV30) - EURAMET.M.H-K1.b and c

This report describes the method and results of a bilateral EURAMET Key Comparison in Vickers hardness scales of two National Metrology Institutes (NMIs) of Italy and Turkey, INRiM and UME, respectively. The Pilot Laboratory (PL) is INRiM in the comparison in which one set of hardness reference blocks with three hardness levels for the Vickers Hardness scales of both HV1 and HV30 was used. The comparison was realized as planned in the Technical Protocol with some delay. The aim of this comparison is to link the UME measurement results to the CCM.H-K1.b.c through the PL (INRiM) as a participant of the CCM key comparison. The measurement results and uncertainty assessments declared by INRiM and UME are in consistency with each other and UME results are also in consistency with the CCM.H-K1.b.c Key Comparison Reference Values (KCRVs). The CCM.H-K1.b.c was realized during 2001 to 2003 to investigate the metrological equivalence of national standards among national metrology institutes (NMIs) within the CCM

Result analysis of EURAMET Vickers comparison between INRiM and UME (EURAMET.M.H-K1.b.c)

A bilateral key comparison between INRiM (National Metrology Institute of Italy) and TUBITAK UME (National Metrology Institute of Turkey) had been decided to be organized in the field of Hardness Metrology to determine the consistency of the national hardness standards in both countries realizing Vickers Hardness measurements in accordance with ISO 6507–1:2018 [1] and ISO 6507–3:2018 [2] standards. Widely used Vickers Hardness scales such as HV1 and HV30 constitute the scope of the comparison which was piloted by INRiM. In this paper the procedure and measurement results of the bilateral EURAMET key comparison between the two laboratories are explained

Preliminary results of EURAMET Rockwell comparison between INRiM and UME (EURAMET.M.H-S1.A.B.C)

A bilateral supplementary comparison between INRiM (National Metrology Institute of Italy) and UME (National Metrology Institute of Turkey) had been decided to be organized in the field of Hardness Metrology to determine the consistency of the national hardness standards in both countries realizing Rockwell Hardness measurements in accordance with ISO 6508-1:2016 [1] and ISO 6508-3:2015 [2] standards. In this paper the procedure and preliminary measurement results of the bilateral EURAMET supplementary comparison between the two laboratories are explained

Result analysis of EURAMET Brinell comparison between INRiM, UME and PTB (EURAMET.M.H–S2.A.B)

A EURAMET supplementary comparison between INRiM (National Metrology Institute of Italy), UME (National Metrology Institute of Republic of Turkey) and PTB (National Metrology Institute of Germany) had been decided to be organized in the field of Hardness Metrology to determine the consistency of the national hardness standards in these three countries realizing Brinell Hardness measurements in accordance with ISO 6506–1:2014 [1] and ISO 6506–3:2014 [2] standards. Widely used Brinell Hardness scales such as HBW 1/30 and HBW 2.5/187.5 constitute the scope of the comparison. In this paper the procedure and comparison results are explained

The role of cigarette butts as vectors of metals in the marine environment: Could it cause bioaccumulation in oysters?

Tobacco is a well-documented threat to human health. However, its environmental impact has only recently been considered. Metals can interact with cigarette butts (CBs) being transported in the marine environment and reaching organisms. To understand this mechanism, a series of metal(loid)s were analyzed in cigarette filters (virgin, artificially smoked, leached in seawater and aged in beach and harbour) as well as in artificially contaminated oyster tissues. Smoked filters showed higher levels of metals compared to the virgin ones showing enrichment factors up to 90, probably associated with tobacco metal content. Once the CBs are delivered to the environment, metals can be leached to seawater until reaching equilibrium, which may be dependent on initial metal levels in the water. Copper was the element with the highest percentage of desorption (91 ± 3%) while strontium showed the lowest percentage (40 ± 0%). CBs revealed a great capacity to accumulate metals from the environment when weathered in contaminated areas. A chemical impact derived from CBs contamination might exist as they serve as a carrier for metals in the marine environment. The release of metals from CBs or the ingestion of metal loaded CBs may pose a toxicological risk for marine organisms via accumulation in their tissues.Versión del edito

Beyond What Meets the Eye: Imaging and Imagining Wood Mechanical–Structural Properties

Abstract: Wood presents a hierarchical structure, containing features at all length scales: from the tracheids or vessels that make up its cellular structure, through to the microfibrils within the cell walls, down to the molecular architecture of the cellulose, lignin, and hemicelluloses that comprise its chemical makeup. This structure renders it with high mechanical (e.g., modulus and strength) and interesting physical (e.g., optical) properties. A better understanding of this structure, and how it plays a role in governing mechanical and other physical parameters, will help to better exploit this sustainable resource. Here, recent developments on the use of advanced imaging techniques for studying the structural properties of wood in relation to its mechanical properties are explored. The focus is on synchrotron nuclear magnetic resonance spectroscopy, X‐ray diffraction, X‐ray tomographical imaging, Raman and infrared spectroscopies, confocal microscopy, electron microscopy, and atomic force microscopy. Critical discussion on the role of imaging techniques and how fields are developing rapidly to incorporate both spatial and temporal ranges of analysis is presented

The effect of postmenopausal hormone replacement therapy on lens opacities and intraocular pressure

Objective: The aim of this study was to determine whether different postmenopausal hormone replacement therapies (HRT) reduced age-related cataract and influenced intraocular pressure (IOP). Material and Methods: One hundred forty eight women on HRT for at least 4 years were included in this prospective study. Group 1 (n= 34) was on 2 mg of 17 beta estradiol, group 2 (n= 41) was on 2 mg of 17-beta estradiol and 1 mg of norethisterone acetate, and group 3 (n= 35) took 2.5 mg of tibolone. The control group (n= 38) did not take HRT. We investigated the association between postmenopausal HRT, lens opacities and IOP in different groups. Lens status was evaluated through a dilated pupil by means of a standardized grading system. The IOP was measured by a single examiner with standard Goldmann applanation tonometry. The tonometric value was considered the mean of three consecutive measurements. Results: The mean ages in the control group, group 1, group 2, and group 3, were 52.44 ± 5.89, 50.87 ± 3.53, 52.05 ± 4.60, and 51.05 ± 3.07, respectively. There were no significant differences between the groups regarding age (p= 0.143) and among the 3 groups regarding HRT years (p= 0.176). We did not observe any significant difference between the groups with respect to the frequency of nuclear opacity (p= 0.361), cortical opacity (p= 0.960), and posterior subcapsular opacity (p= 0.856). In addition, there were no significant differences when we compared the IOP findings between the groups (p= 0.847). Conclusion: These findings suggest that HRT for 4 years is not protective against lens opacity, and does not modify IOP. Copyright © 2007 by Türkiye Klinikleri

Effect of corneal thickness on intraocular pressure measurements with the Pascal dynamic contour, Canon TX-10 non-contact and Goldmann applanation tonometers in healthy subjects

PubMedID: 18637107Purpose: To investigate the effects of central corneal thickness (CCT) on intraocular pressure (IOP) measurements of the Pascal dynamic contour tonometry (DCT), Canon TX-10 non-contact tonometry (NCT) and Goldmann applanation tonometry measurements (GAT) in healthy subjects. Methods: IOP values of 135 eyes with normal corneas of 135 healthy volunteers were determined by DCT, NCT and by GAT. The CCT was measured using an ultrasonic pachymeter after all IOP determinations had been made. Results: When DCT measurements were compared (IOP = 17.52 ± 2.0 mmHg) with NCT measurements (IOP = 16.54 ± 2.77 mmHg) and GAT measurements (IOP = 15.07 ± 2.35 mmHg), DCT measurements were significantly higher than NCT and GAT (p < 0.001). There was a significant correlation between CCT with both NCT (r = 0.260, p = 0.003) and GAT measurements (r = 0.257, p = 0.005). There was a weak correlation that was not statistically significant between CCT and DCT (r = 0.160, p = 0.079). Conclusion: The IOP measurements with DCT seem to be less dependent on CCT. NCT appears to be more affected by variation in CCT than GAT. © 2008 Optometrists Association Australia

Value of color Doppler ultrasonography in the evaluation of orbital vascular flow in end-stage renal disease patients undergoing hemodialysis

WOS: 000226031800011PubMed ID: 15690616Purpose: To evaluate choroidal and retinal vascular flow dynamics by means of color Doppler ultrasonography in patients with end-stage renal disease undergoing hemodialysis and to compare these findings with healthy controls. Material and Methods: Color Doppler ultrasonography and spectral analysis of nasal and temporal posterior ciliary and central retinal artery flow of both eyes were performed in 20 patients (40 eyes) and 22 controls (44 eyes) to assess peak systolic flow velocity, end-diastolic flow velocity, and resistive indices (RI). Patients with hypertension, diabetes mellitus, and any cardiac pathology were not included in the study. A general ophthalmologic examination was performed in all patients and controls. Results: The average peak-systolic and end-diastolic blood flow velocities of nasal (12.88+/-4.91/6.88+/-3.26) and temporal (15.22+/-9.59/6.41+/-3.97) posterior ciliary artery and central retinal artery (14.94+/-8.38/6.7+/-4.13) in patients were significantly higher than the corresponding values of the controls. The RI values of nasal (0.52+/-0.10) and temporal (0.58+/-0.12) posterior ciliary artery and central retinal artery (0.55+/-0.11) in patients with end-stage renal disease undergoing hemodialysis were significantly lower than in the controls. Conclusion: Choroidal and retinal blood flow velocities are higher and RI values for all three vessels lower in patients with end-stage renal disease undergoing hemodialysis compared to healthy controls. These alterations may be related to either increased choroidal blood flow or vasoconstriction of the proximal vessels

Pars plana vitrectomy in ocular Behçet's disease

PubMedID: 12678399Purpose: To evaluate the results of pars plana vitrectomy in Behçet patients with dense vitreous opacities, and its effect on intraocular inflammatory episodes and visual prognosis. Methods: The study group consisted of nine patients (one eye in eight patients, both eyes in one) with Behçet's disease who underwent pars plana vitrectomy because of dense vitreous opacification. The indications for vitrectomy, the effect of vitrectomy on the frequency of severe intraocular inflammatory episodes, and visual prognosis were investigated in these patients. All the patients were male, and their ages ranged between 28-45 years. Combined lensectomy was performed on those with complicated cataracts. The postoperative follow-up was between 12-66 months. Results: In all of the patients preoperative visual acuity was hand motions. Postoperatively there was no change in vision in five eyes, however visual acuity improved in five eyes, between counting fingers and 0.4. None of the patients showed any severe postoperative intraocular inflammatory episodes, and phthisis did not develop in any of the patients. Conclusion: In this study, pars plana vitrectomy was found to have a beneficial effect on the prognosis of vision. There was also a decrease in the frequency of severe intraocular inflammatory episodes n patients with Behçet's disease with severe vitreous opacities, who did not respond to maximum medical treatment. However, further studies on larger groups should be performed in order to confirm the findings of this study