Standard Measurement Methods Research Articles

Loneliness Gets Under the Skin: A Scoping Review Exploring the Link Between Loneliness and Biological Measures of Inflammation.

Research suggests that systemic inflammation may link loneliness to adverse health outcomes, yet there is a gap in comprehensively reviewing recent evidence on the relationship between loneliness and biological measures of inflammation in adults. This scoping review synthesizes current research to address the question: Is there a definitive link between loneliness and biological markers of inflammation in adults? Following the methods outlined by Arksey and O'Malley, we developed a protocol, defined our research question, and systematically searched PubMed, CINAHL, Embase, and Scopus for English-language studies conducted from 2018 to 2023 exploring the relationship between loneliness and biomarkers of inflammation in adults. Twelve studies meeting the inclusion criteria displayed heterogeneity in terms of sample characteristics, loneliness scales, and inflammatory biomarkers. The UCLA Loneliness Scale, in various forms, emerged as the predominant tool for measuring loneliness, while C-reactive protein and interleukin-6 were the most frequently evaluated inflammatory biomarkers. Notably, all 12 studies reported an association between loneliness and at least 1 biological marker of inflammation. Research consistently associates loneliness with poor health outcomes in aging adults, but the underlying mechanisms remain unclear. This scoping review suggests that inflammation may serve as a pathway linking loneliness to adverse health outcomes. However, the variability across studies highlights the need for standardized measurement methods and a consideration of both the duration and extent of loneliness. Enhancing our understanding of how loneliness affects systemic inflammation may help clarify why loneliness is associated with negative health outcomes.

Low-Cost Device for Measuring Wastewater Flow Rate in Open Channels

This research paper describes the development of a low-cost device for measuring wastewater flow rates in open channels, a significant advancement enabled by the evolution of microcomputers and processing techniques. A laboratory setup was constructed to validate the device’s accuracy against a standard flow measurement method, optimizing key parameters to achieve a linear relationship between detected and set flow rates, while considering hardware limitations and energy efficiency. The central focus of the research was developing a method to measure the velocity of contaminated fluid using ultrasonic signals, employing the cross-correlation method for signal delay analysis in a stochastic environment. This was complemented by a procedure to measure fluid levels, also based on ultrasonic signals. The device’s reliability was assessed through repeatability and uncertainty measurements, confirming its accuracy with an extended uncertainty not exceeding an average of 3.47% for flows above 40 L/min. The device has potential to provide valuable data on the operational dynamics of sanitary networks, crucial for developing and calibrating simulation models.

Determination of terpene-based VOCs emitted from pine wood using NIR spectroscopy

ABSTRACT In the search for a quick and less labor-intensive method for determining terpene emissions of high emitting wood like Pinus sylvestris, this study utilized near-infrared spectroscopy (NIR) combined with multivariate analysis methods and compared it to the standard measurement method according to the EN 16516 standard. The spectra were measured on the surface of solid-wood samples and correlated with the simultaneously determined air concentrations of terpenes. For α-pinene and 3-carene, prediction models were created using partial least squares regression (PLSR). Both work with determination coefficients of 0.77 and a Root Mean Square Error of Prediction (RMSEP) of 12% of the maximum emissions achievable in this study. A model based on the sum of the two terpenes was built and tested to determine the predictive capability of multiple similar substances simultaneously from the NIR recording. The model performs slightly worse, with a determination coefficient of 0.71 and RMSEP of 13%. Despite continuous expansion of the datasets for multiple models, no better metrics were achieved, likely because of the heterogeneous structure of wood when scanning a solid-wood surface. Systematic deviations were observed in particularly low reference ranges, which may indicate non-linearity in the relationship between terpenes and the NIR signal.

Vibration reduction index improvement by adding resilient strips: influence of junction properties

Resilient strips can be used to decrease the structural transmission in junctions and thus limit the flanking sound transmission in buildings. In the standard ISO 12354-1, the efficiency of a resilient strip is characterized by the vibration reduction index improvement. To evaluate the vibration reduction improvement, a standardized measurement method is needed. However, the vibration reduction improvement is not an intrinsic material parameter of the resilient strip and can depend on the mounting conditions and junction geometry. In this paper, the vibration reduction index improvement is evaluated by means of numerical simulations carried out with a statistical model for junctions with resilient strips. The model was first validated by laboratory measurements. While the influence of the junction type (L, T or X) and transmission path (straight on or around the corner) is limited, the influence of the plate properties (mass and bending stiffness) cannot be neglected, with differences in vibration reduction improvement of up to 20 dB.

Sound Source Localization at the Rolling Tire

A vehicle's tire rolling on pavement causes complex noise generating mechanisms which are a dominant sub-source of vehicle traffic noise. For the quantification of noise levels due to these tire-pavement interactions, standardized acoustic measurement methods exist, such as the Close-Proximity (CPX) method. These methods require microphones mounted near a rolling tire. However, they do not provide insight in the distribution and amplitudes of present sound sources. In this contribution, we aim at identifying the dominant sound sources of the rolling tire at discrete frequencies. This is accomplished by an inverse method combining microphone array measurements and Finite Element (FE) simulations. The microphone measurements were recorded on Austrian highways with a large measurement trailer built for research purposes. With the considered inverse method, not only the amplitudes of the dominant sound sources but also their phases can be identified. With these identified sources and a validated FE model of the measurement trailer, the sound pressure field within the trailer may be computed. The thereby calculated sound pressure is compared to measurements at the CPX microphone positions and other locations within the trailer.

Resonant frequencies of multi-layer building constructions: Estimation by measurement of acceleration amplitudes

The Austrian building regulation requirements for impact sound insulation are based on the weighted standardized impact sound pressure level as single-number specification. In recent years, it has become apparent that not only the single-number specification, but the extended frequency range and frequency characteristics of impact sound insulation of constructions can have noticeable influence on the perceived acoustic performance of a construction. Therefore, the Austrian Classification Standard ÖNORM B 8115-5: 2021-04 includes extended requirements on impact sound insulation. It provides two ways for verification of the sound insulation classes A to C. One way is the verification via the resonance frequency of multi-layer constructions. However, there exist as yet no standardized measurement methods for the estimation of the resonance frequency of multi-layer building constructions. In response, in course of this study a new measurement method for the estimation of the resonance frequencies of multi-layer constructions was developed. For this development acceleration measurements were carried out on both surfaces of particularly double-layer building constructions, that were excited with a rubber hammer. From these measurement results, in conjunction with an analytical model, it was possible to derive a measurement method for estimating the resonant frequency via the frequency characteristics of the acceleration amplitudes.

A-223 Direct LDL or not Direct-LDL, that is the question

Abstract Background Management of Cardiovascular Disease (CVD) risk is dependent on Low Density Lipoprotein Cholesterol (LDL-C) levels; therefore LDL-C serves as the marker for the assessment of CVD risk and the focus of lipid lowering treatment. The gold standard reference method for measurement of LDL-C is beta-quantification. We compared calculated LDL-C with Friedewald (F-LDL-C), Martin-Hopkins (M-LDL-C) and Sampson (S-LDL-C) equations versus LDL-C directly measured (D-LDL-C). In CVD management also cholesterol ratios are evaluated. TC/HDL is associated with morbidity and mortality in the general population. Furthermore, several studies have stated that high triglycerides (TG) levels and low HDL-C (TG/HDL ratio) could function as an atherogenic index. Methods 11399 samples were analyzed on Siemens Atellica Solution® for the lipid profile determination measuring Total Cholesterol (TC), D-LDL-C, HDL-C and TG. In the absence of additional clinical parameters, based on desirable levels for LDL-C recommended by guidelines, CVD risk was evaluated by assigning to LDL-C a cut-off of 100 mg/dL. In presence of misclassifications, we used two other parameters to assess LDL-C results: TG/HDL-C ratio and CT/HDL-C. Results Patients cohort had a mean age of 57.7 (±16.8) years of which 53% (age=58.6, ±15.9) were males and 47% (age=56.5, ±17.8 years) were females. Of these, the 57.7% were outpatients and 42.3% inpatients (42.1% of infectious diseases - 24.4% of the cardiovascular department). Data about LDL-C misclassification and ratio data parameters are shown in table 1. Discordant patients for D-LDL-C vs F-LDL-C are 8.5%, that of D-LDL-C vs M-LDL-C are 7.7% and D-LDL-C vs S-LDL-C are 7.2%. Conclusions Is known that LDL plays a central role in the pathogenesis of atherosclerosis. Accurate estimation of LDL-C is a fundamental point for the stratification of CVD risk and the achievement of the therapeutic goal; however, we are still uncertain about the best and accurate way to measure it.

Relationship between asymmetry of transverse sinus and difference in intraocular pressure Based on MRV imaging examination

Transverse sinus asymmetry refers to the inconsistencies in the shape structure, size or blood flow of the intracranial transverse sinus. Intraocular pressure difference refers to the obvious difference in intraocular pressure between the two eyes. Transversal sinus asymmetry may be correlated with intraocular pressure difference, but the mechanism of correlation is still unclear. To investigate the relationship between transverse sinus asymmetry and IOP differences based on MRV examination, and to explore the possible mechanism. Patients with transverse sinus asymmetry were selected and examined using the MRV technique. At the same time, the patients' IOP was measured using standard methods of IOP measurement. Correlation analysis and statistical methods were used to evaluate the association between transverse sinus asymmetry and IOP differences. There was a statistically significant distinction observed between groups I and V (Z=6.78, P<0.01). Significant variations were also noted in the intraocular pressures across all groups, encompassing the average measurements of the right eye and left eye, along with the variance between the two (right eye: F=15.43, P<0.01; left eye: F=4.62, P=0.002; variance between eyes: F=41.79, P<0.01). The asymmetry of the transverse sinus exhibited a negative relationship with the intraocular pressure of the right eye (r=0.51, P<0.01) and the difference between the pressures of the two eyes (r=0.79, P<0.01); no significant association was found between the asymmetry and the left eye's intraocular pressure. In conclusion, a certain correlation exists between the intraocular pressures of the left and right eyes and the morphology of the transverse sinus. When the transverse sinus is thicker on one side, the corresponding drainage veins are thicker, resulting in lower intraocular pressure on that same side.

Sensitivity and accuracy of single-mode fiber optic sensor for non-invasive glucose measurement

Abstract Routine glucose level monitoring is essential for diabetic patients. Standard measurement methods based on finger pricking are inconvenient and susceptible to infection risk. Therefore, simple and non-invasive measurements are urgently needed. Compared to other approaches, glucose level measurement using optical methods offers many advantages, such as set-up simplicity, high sensitivity, and high accuracy. We optimize the sensing performance of glucose level sensors based on a single-mode fiber optic. The fiber optic serves as a medium for light propagation from a diode laser to a photodiode and, at the same time, serves as an active sensing medium. In the sensing area, the fiber optic cladding is partly (i.e., 1 – 5 cm) stripped to allow direct contact, which leads to evanescent wave absorption by glucose molecules. The length of fiber optic stripping and bending radius, which determine the sensitivity and accuracy of the sensor, varied. Bent fiber optic sensors consistently show a higher sensitivity and accuracy than straight ones. Maximum sensitivity of 2.35 mV/(mg/dL) was attained for a 3 cm stripping length and 4.5 cm bending radius. The lowest sensitivity of the sensor, 0.453 mV/(mg/dL), was acquired at the stripping length of 5 cm for the straight fiber optic sensor. The highest accuracy of the developed sensor is 99% for bent fiber optic sensors.

A Field‐Based Estimation of the Variability of Particle Entrainment in Coarse‐Bed Rivers

AbstractThe determination of critical shear stresses is fundamental to bedload sediment transport prediction in gravel‐bed rivers. Due to the heterogeneous shape and arrangement of the individual clasts in a riverbed, critical shear stresses typically show a large spatial variability, which is not adequately captured by the reach‐averaged description followed in common studies. In this regard, there is a general paucity of field data on this spatial variability of the critical shear stress, largely due to the lack of a standardized measurement method. In an attempt to fill this gap, we propose a field‐based workflow to estimate the frequency distribution of dimensionless critical shear stress (also named critical Shields number), which is based on the measurement of a series of variables related to the position, orientation and resistance to motion of individual clasts in a gravel‐bed river, combined with a probabilistic approximation to drag and lift coefficients. Following this workflow, the patch‐scale variability of particle incipient‐motion conditions was determined in a gravel bar of the Upper Cinca River, Spain. The results are consistent with what is known about sediment entrainment in gravel‐bed rivers. We consider this method to have great potential to advance our understanding of particle initiation of motion in gravel‐bed rivers as it provides valuable systematic field information.

Revisiting a decade of inequality in healthcare financial burden in Cambodia, 2009–19: trends, determinants and decomposition

BackgroundOut-of-pocket healthcare expenditure (OOPHE) without adequate social protection often translates to inequitable financial burden and utilization of services. Recent publications highlighted Cambodia’s progress towards Universal Health Coverage (UHC) with reduced incidence of catastrophic health expenditure (CHE) and improvements in its distribution. However, departing from standard CHE measurement methods suggests a different storyline on trends and inequality in the country.ObjectiveThis study revisits the distribution and impact of OOPHE and its financial burden from 2009–19, employing alternative socio-economic and economic shock metrics. It also identifies determinants of the financial burden and evaluates inequality-contributing and -mitigating factors from 2014–19, including coping mechanisms, free healthcare, and OOPHE financing sources.MethodsData from the Cambodian Socio-Economic Surveys of 2009, 2014, and 2019 were utilized. An alternative measure to CHE is proposed: Excessive financial burden (EFB). A household was considered under EFB when its OOPHE surpassed 10% or 25% of total consumption, excluding healthcare costs. A polychoric wealth index was used to rank households and measure EFB inequality using the Erreygers Concentration Index. Inequality shifts from 2014–19 were decomposed using the Recentered Influence Function regression followed by the Oaxaca-Blinder method. Determinants of financial burden levels were assessed through zero-inflated ordered logit regression.ResultsBetween 2009–19, EFB incidence increased from 10.95% to 17.92% at the 10% threshold, and from 4.41% to 7.29% at the 25% threshold. EFB was systematically concentrated among the poorest households, with inequality sharply rising over time, and nearly a quarter of the poorest households facing EFB at the 10% threshold. The main determinants of financial burden were geographic location, household size, age and education of household head, social health protection coverage, disease prevalence, hospitalization, and coping strategies. Urbanization, biased disease burdens, and preventive care were key in explaining the evolution of inequality.ConclusionMore efforts are needed to expand social protection, but monitoring those through standard measures such as CHE has masked inequality and the burden of the poor. The financial burden across the population has risen and become more unequal over the past decade despite expansion and improvements in social health protection schemes. Health Equity funds have, to some extent, mitigated inequality over time. However, their slow expansion and the reduced reliance on coping strategies to finance OOPHE could not outbalance inequality.

Elimination of the methodological error in measuring linear parameters of electrical cables for intrinsically safe systems

The necessity of monitoring the linear electrical parameters of cables for intrinsically safe applications is described and it is indicated that the manufacturer or supplier of cables must ensure that the cable parameters comply with current standards. The problem of unproductive consumption of cable products during its control is considered. It is noted that standard measurement methods for such a linear parameter as inductance are correct when using cable samples, the length of which is much shorter than the construction lengths. An analytical model of a cable line as an electrical facility with distributed parameters is investigated. The reason for the introduction of a limit on the length of the cable is shown, caused by the transition from a complete to a simplified model traditionally used in some standards.A systematic method for measuring the linear parameters of cables is proposed, based on an unconventional – reverse – solution, which consists in switching from the measured secondary parameters to the calculation of primary parameters. In this case, the secondary parameters are measured in accordance with the well – known standardized idling – short circuit method. The proposed method is practically free from the limitation of the length of cable samples. This allows you to control all finished cable products without cutting off samples for measurements. The measurement error does not exceed the limit set by the standards equal to 1 %. The results obtained provide non-destructive testing during acceptance tests of cable products intended for intrinsically safe systems.

Morphometrical analysis of myelinated nerve fibers: is there a room for improvement?

Despite advancements in automatic approaches for histomorphometry analysis of peripheral nerves, manual and semi-automated methods are widely utilized. Standard software functions are often unsuitable for analysis due to their irregular shapes, especially in pathological conditions. This study aims to assess the reproducibility of nerves morphometric analysis and compare results obtained using both default and new alternative algorithms. Sciatic nerves from Wistar rats (untreated and after administration of intraperitoneal hydrargyrum chloride), previously embedded in resin, were used. Morphometric analysis (diameters, myelin thickness, g-ratio, and circularity) was conducted using ImageJ on semithin sections, with axon and myelin boundaries manually outlined. Default diameters were calculated as the mean of Feret diameters, with subsequent calculations for myelin thickness and g-ratio. The alternative approach estimated diameters based on the geometric center of axons, iterating through selected coordinates; myelin thickness was obtained using line equations. In the control group, inter-rater agreement was higher or within expected reliability (0.8 ± 0.05). However, in the experimental group, myelin thickness, g-ratio, and axon circularity showed lower agreement (0.66, 0.58, and 0.68, respectively) without visible patterns on Bland-Altman plots. The alternative approach did not reveal significant differences between approaches, except for g-ratio in the control group and fiber diameter in the experimental group (p < 0.05), with effect sizes of 0.29-0.30 and 0.19-0.20, respectively. This study highlights reduced agreement among investigators analyzing nerve fibers under pathological conditions, raising concerns about the current standard measurement methods. The proposed approach, based on a single geometric center, provides more natural estimations for irregular fibers, and can be implemented in automated nerve fibers acquisition systems.

PROTEIN ELECTROPHORESIS AND REFERENCE INTERVALS OF SERUM PROTEINS OF A CAPTIVE POPULATION OF ROTI ISLAND SNAKE-NECKED TURTLES (CHELODINA MCCORDI).

Protein electrophoresis (PEP) is an important tool in mammals to characterize specific dysproteinemias and detect acute and chronic inflammatory responses. In reptiles, PEP is the gold standard method for globulin fraction determination and albumin measurement. In this study, preliminary reference intervals were established for serum PEP in 22 clinically healthy adult Roti Island snake-necked turtles (Chelodina mccordi), a critically endangered species, kept in captivity and sampled over two monsoon seasons. The species has a prominent prealbumin fraction and β-globulins were the dominant globulin fraction. Significant differences between females and males were found in prealbumin (P < 0.01), albumin (P = 0.02), α1-globulin (P = 0.05) and γ-globulin (P = 0.01). Gravid females had significantly lower total protein (P < 0.01), prealbumin (P < 0.01), albumin (P < 0.01) and albumin:globulin ratio (P = 0.01). These preliminary reference intervals should aid in clinical investigation in this species as well as further research studies seeking to understand the application of PEP in reptilian species.

Behaviour of dissolved inorganic salts in the cooling water of a nuclear power plant open recirculation system and formation of water discharge.

The main problem in the operation of nuclear power plants (NPPs) is the scale formation of mineral impurities in an open recirculating system (ORS). The discharge of water from an ORS into natural water bodies can alter the chemical equilibrium of wastewater components, necessitating continuous monitoring. The purpose of this study was to analyse the behaviour of dissolved inorganic salts (DIS) in water within an ORS during water treatment, using the Rivne Nuclear Power Plant (RNPP) as a case study. Moreover, the analysis impact of their discharge with return water in the Styr River. The DIS concentration has a significant impact on the efficiency of the system and the environmental of an ORS power plant. Altogether, each of the DIS components was analysed separately using the standard measurement methods, statistical methods of data processing and correlation analysis. In addition, the annual discharge of the DIS components was calculated, and the amount of discharge was assessed for compliance with the maximum discharge limit. Thus, the impact of the formation of DIS and the variations in their concentration levels upon the discharge of wastewater into a natural water body were examined.

Comparison of continuous temperature measurement methods in the intensive care unit: standard bladder catheter measurements versus non-invasive transcutaneous sensors.

The purpose of this study was to compare a wearable system for body core temperature measurement versus bladder and tympanic thermometers in an intensive care setting. The question was, if continuous non-invasive sensors in the intensive care unit represent an alternative to current standard methods of invasive continuous bladder temperature measurement methods?Between May and September 2023, a comparative investigation involving 112 patients was conducted in a 20-bed surgical intensive care unit to assess various temperature probes, including those placed in the tympanic tube, bladder, and skin. To achieve this, a wireless non-invasive sensor system provided by greenTEG AG, Switzerland, was affixed to different body locations (clavicular and lateral chest) of each catheterized patient (equipped with a temperature probe) admitted to the intensive care unit. Furthermore, tympanic temperatures were recorded at specified intervals. The measurement duration ranged from a minimum of six hours to a maximum of six days, resulting in the analysis of a total of 355 simultaneous temperature measurements.In this study, a wearable temperature measurement system attached to two different body sites revealed a consistent negative bias compared to bladder temperature. In addition, the measurements were particularly influenced by body constitution. The tested system in all patients showed a mean absolute error (MAE) of 0.45°C for the lateral chest and 0.50°C for the clavicular position. Tympanic measurements had a mean absolute error of 0.35°C. In patients with body mass index (BMI) ≥ 25 the MAE increased to 0.5°C for the lateral chest and 0.56°C for the clavicular position. In contrast, the tympanic measurement had a reduced MAE of 0.32°C, which is well below this threshold when compared to bladder measurements.In conclusion the investigated system did not meet the clinically relevant acceptance criteria and showed low precision in correctly identifying fever episodes compared to invasive temperature probes, however its main advantage lies in its continuity and non-invasiveness. This makes it a potential alternative to intermittent tympanic measurement devices. In this study we were able to show, that in at least one subset of patients, the non-invasive and continuous device demonstrated a precision comparable to tympanic measurements.The accuracy of all non-invasive methods was lower than in previous studies, suggesting that the use of bladder temperature as reference and user related variations may have introduced additional errors.

Comparability analysis of the HNT-1P Huvitz non contact tonometer for the measurement of intraocular pressure.

To evaluate the diagnostic validity of the HNT-1P non-contact tonometer (Huvitz) as a tool for accurately measuring intraocular pressure (IOP) in patients with healthy eyes, compared to the Goldmann applanation tonometer (GAT), which is the Gold Standard method for measurement of IOP. Observational, descriptive, transversal study using 148 eyes of 74 healthy patients without a diagnosis of glaucoma or other ophthalmological diseases. Three measurements of IOP were taken in each eye, using three tonometers: HNT-1P, ICR100, and GAT. The median IOP (quartiles) and mean IOP (SD) its statistical significance were calculated, and comparisons were made between the mean and median IOP values found in three groups: GAT-HNT, GAT-ICR, and HNT-ICR. The difference in mean and median IOP was analyzed in each of the three study groups, and its statistical significance and concordance correlation coefficient (CCC) were calculated. The median IOP with HNT-1P was statistically significantly lower than the median IOP with GAT, (1.1 mmHg, p < 0.001). The median IOP with HNT-1P was also lower than the median IOP with ICR100. As an additional result, the median IOP with GAT was lower than the median IOP with ICR. The CCC was moderate for HNT-ICR (0.72) and low for GAT-HNT and GAT-ICR (0.43 and 0.38, respectively). HNT-1P (Huvitz) provides statistically significantly lower IOP values than those obtained with GAT. HNT-1P could be used for screening of ocular hypertension in postoperative patients. The IOP measurement obtained with HNT-1P should be confirmed with GAT. HNT-1P yields lower IOP values than those obtained with ICR.

Wetsuit Thermal Resistivity Measurements.

In recent years, attention to the realization and characterization of wetsuits for scuba diving and other sea sports or activities has increased. The research has aimed to establish reliable and standardized measurement methods to objectively assess wetsuit quality, particularly focusing on their mechanical and thermal properties. In this work, we describe and compare two different measurement methods for the characterization of neoprene wetsuit thermal resistivity. The first method follows the existing regulations in the field, while the second one, which we are originally proposing in this paper, offers an alternative yet accurate way based on a simplified experimental set-up and easier measurements. In both cases, the wetsuit sample under testing was shaped in the form of a cylindrical sleeve of proper dimensions and wrapped around a phantom containing water at a higher temperature and surrounded by water at a lower temperature. The wetsuit's cylindrical surface allows heat flow from the warmer water on the inside to the colder water on the outside through the wetsuit area. In the first case, a thermal steady state was achieved, with constant heat flow from the phantom to the exterior. This was obtained with a power balance between two homogenous quantities. Electrically supplied thermal heating within the phantom was used to balance the thermal energy naturally flowing through the wetsuit's surface. In this first case, a stable and fixed temperature difference was obtained between the inner and the outer surfaces of the wetsuit sample. In the second case, a thermal transient was analyzed during the cooling process of the phantom, and the thermal time constant was measured, providing the sample thermal resistance once the phantom thermal capacity was known. In both cases and methods, the heat flow and thermal resistance of other elements than the wetsuit must be evaluated and compensated for if they are not negligible. Finally, the thermal resistivity per unit area of the wetsuit material was obtained with the product of the wetsuit sample's thermal resistance and the wetsuit area. The measurements, conducted until now by immersing the phantom in a free surface tank, show that both methods-under stationary and under transient temperature conditions-were valid to assess the wetsuit's thermal resistivity. The stationary method somehow provided better accuracy while involving less well-known parameters but at the expense of a more complicated experimental set-up and additional energy consumption. The transitory method, on the other hand, is quite easy to implement and, after careful characterization of the phantom's parameters, it provided similar results to the stationary one. An uncertainty budget was evaluated for both methods, and they did provide highly compatible measurement results, with resistivity values of 0.104(9) m2·K/W (stationary method) and 0.095(9) K·m2/W (transient method) for the same wetsuit sample under testing, which is also consistent with the values in the literature. We finally propose that the novel method is a valid alternative for characterization of the thermal insulation properties of a scuba diving wetsuit.

Amplitude of Accommodation in Young Caucasian Adults in Greece

Objective: This study aims to determine the prevalence of accommodation insufficiency among young Caucasian adults in Greece. Methods: Accommodation amplitude was assessed using the minus to blur method (PRA). Results were compared against Donder's and Hofstetter's values. Participants were categorized into "normal," "borderline," and "insufficient" based on deviations from expected values. Results: Over 50% of participants exhibited accommodation insufficiency. Men had significantly lower rates of normal accommodation amplitude compared to women. Further research is required to explore the impact of refractive errors on accommodation issues. Conclusions: Accommodation insufficiency is a significant issue among young adults, necessitating further studies and the establishment of standardized measurement methods. Investigating the role of the ciliary muscle in accommodation is also recommended.

Elastic strain mapping of plastically deformed materials by TEM

A method for mapping elastic strains by TEM in plastically deformed materials is presented. A characteristic feature of plastically deformed materials, which cannot be handled by standard strain measurement method, is the presence of orientation gradients. To circumvent this issue, we couple orientation and strain maps obtained from scanning precession electron diffraction datasets. More specifically, orientation gradients are taken into account by 1) identifying the diffraction spot positions in a reference pattern, 2) measuring the disorientation between the diffraction patterns in the map and the reference pattern, 3) rotating the coordinate system following the measured disorientation at each position in the map, 4) calculating strains in the rotated coordinate system. At present, only azimuthal rotations of the crystal are handled. The method is illustrated on a Cr2AlC monocrystal micropilar deformed in near simple flexion during a nanomechanical test. After plastic deformation, the sample contains dislocations arranged in pile-ups and walls. The strain-field around each dislocation is consistent with theory, and a clear difference is observed between the strain fields around pile-ups and walls. It is further remarked that strain maps allow for the orientation of the Burgers vector to be identified. Since the loading undergone by the sample is known, this also allows for the position of the dislocation sources to be estimated. Perspectives for the study of deformed materials are finally discussed.