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Background: The optimal site for measuring computed tomography (CT)-derived fractional flow reserve (FFRCT) to detect significant coronary artery disease (CAD) remains unknown. We investigated how diagnostic performance changes with FFRCT measurement site. Methods and Results: The diagnostic performance of FFRCT, measured 1–2 cm distal to the stenosis vs. a far-distal site, in detecting significant CAD with invasive fractional flow reserve ≤0.8 was evaluated in 254 diseased vessels from 146 patients with stable or suspected CAD diagnosed by coronary CT angiography. Receiver operating characteristic curve analysis revealed a significantly larger area under the curve for FFRCT measured 1–2 cm distal to the stenosis than at a far-distal site (0.829 vs. 0.791, respectively; P=0.0305). The rate of reclassification of positive FFRCT was 19% for measurements made 1–2 cm distal to the stenosis, and diagnostic accuracy for FFRCT 0.71–0.80 improved from 36% to 58% (P=0.0052). Vessel-based diagnostic accuracy of FFRCT 1–2 cm distal to the stenosis and at a far-distal site was 75% and 65%, respectively (P

Growing concern regarding animal welfare has increased the need for reliable methods of assessing the animal health status without stress during commercial farm practice. Measuring the body temperature with a thermal imaging camera is one possible stress-free technique since it is non-contact and non-invasive. The first objective of this study was to determine the best anatomical site in healthy pigs for measuring the temperature with a high spatial resolution thermal imaging camera that gives results equivalent or related to the temperatures measured in the rectum. The second objective was the assessment of the possibility to accurately and reliably measure or predict the pigs’ temperature with a low spatial resolution thermal imaging camera. Reference temperatures, measured with a calibrated thermometer in the rectum, were compared to the measurements of two calibrated thermal imaging cameras (a low resolution camera and a high resolution camera) on four anatomical sites of pigs (ear canal, eye canthus, outer ear and perianal area). We found that it is not possible to accurately measure or predict the pigs’ body temperature with a high noise equivalent temperature difference (NETD), low accuracy, low spatial resolution thermal imaging camera. However, a low NETD, high accuracy, high spatial resolution thermal imaging camera gives at least results that enable prediction (using a linear regression model) of the pigs’ body temperature. We showed that there are three anatomical sites in healthy pigs (ear canal, outer ear, perianal area) that are statistically similarly suitable for predicting the body temperature with a calibrated high spatial resolution thermal imaging camera under non diseased thermal neutral conditions.

Transcutaneous bilirubinometer devices are widely applied to assess neonatal hyperbilirubinemia. However, the optimal skin site and timing of transcutaneous bilirubin (TCB) measurements for the strongest correlation with total serum bilirubin (TSB) levels after phototherapy are still unclear. We conducted a retrospective observational study evaluating the correlation of TCB and TSB levels in neonates postphototherapy. The TCB measurements on the forehead and mid-sternum at 0 and 30 min postphototherapy were assessed by using a JM-103 bilirubinometer. Paired TCB and TSB measurements were assessed by Pearson correlation and Bland–Altman plots. We analyzed 40 neonates with 96 TSB and 384 TCB measurements. The TSB level correlated moderately with the forehead TCB level at 30 min postphototherapy (r = 0.65) and less strongly with the midsternum TCB level at 0 min postphototherapy (r = 0.52). The forehead at 30 min after cessation of phototherapy was the best time point and location of TCB measurement for the assessment of neonatal jaundice status. The reliability of TCB measurements varied across skin sites and durations after phototherapy. The effectiveness of TCB measurement to assess neonatal hyperbilirubinemia is much better on covered skin areas (foreheads) 30 min postphototherapy. The appropriate application of transcutaneous bilirubinometers could aid in clinical practice and avoid unnecessary management.

Carotenoids are a class of phytochemical compounds found in a variety of fruits and vegetables (F/V) and, therefore, are commonly used as a biomarker for F/V intake. The Veggie Meter® is a noninvasive research-grade instrument that detects and quantifies carotenoids in the skin. To determine current practices and examine variability among users, a survey was administered to researchers using the device (n = 19, response rate = 35.8%) and variation in anatomical site preparation, calibration, number of measurements, measurement site, and documentation was observed. A protocol was developed in partnership with Veggie Meter® users to outline the preparation, calibration, and data collection procedures for using this device for research purposes. Although many protocol conditions will benefit from additional validation, this standardized protocol supports the development of a universal data repository to establish usual observed ranges, with the ultimate goal of examining associations between skin carotenoid scores and diet-related health outcomes., Inconsistent data collection procedures among researchers using the Veggie Meter® provided the impetus to develop a standardized protocol for the use of the Veggie Meter® in the research setting.

Ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of aerosols and tropospheric nitrogen dioxide (NO2) were carried out in Uccle (50.8° N, 4.35° E), Brussels, during 1 year from March 2018 until March 2019. The instrument was operated in both the UV and visible wavelength ranges in a dual-scan configuration consisting of two sub-modes: (1) an elevation scan in a fixed viewing azimuthal direction (the so-called main azimuthal direction) pointing to the northeast and (2) an azimuthal scan in a fixed low elevation angle (2°). By applying a vertical profile inversion algorithm in the main azimuthal direction and a parameterization technique in the other azimuthal directions, near-surface NO2volume mixing ratios (VMRs) and vertical column densities (VCDs) were retrieved in 10 different azimuthal directions. The dualscan MAX-DOAS dataset allows for partly resolving the horizontal distribution of NO2around the measurement site and studying its seasonal variations. Furthermore, we show that measuring the tropospheric NO2VCDs in different azimuthal directions improves the spatial colocation with measurements from the Sentinel-5 Precursor (S5P), leading to a reduction of the spread in validation results. By using NO2vertical profile information derived from the MAX-DOAS measurements, we also resolve a systematic underestimation in S5P NO2data due to the use of inadequate a priori NO2profile shape data in the satellite retrieval., SCOPUS: ar.j, info:eu-repo/semantics/published

Background Recently, attempts have been made to use the pulse rate variability (PRV) as a surrogate for heart rate variability (HRV). PRV, however, may be caused by the fluctuations of left ventricular pre-ejection period and pulse transit time besides HRV. We examined whether PRV differs not only from HRV but also depending on the measurement site. Results In five healthy subjects, pulse waves were measured simultaneously on both wrists and both forearms together with single-lead electrocardiogram (ECG) in the supine and sitting positions. Although average pulse interval showed no significant difference from average R-R interval in either positions, PRV showed greater power for the low-frequency (LF) and high-frequency (HF) components and lower LF/HF than HRV. The deviations of PRV from HRV in the supine and sitting positions were 13.2% and 7.9% for LF power, 24.5% and 18.3% for HF power, and − 15.0% and − 30.2% for LF/HF, respectively. While the average pulse interval showed 0.8% and 0.5% inter-site variations among the four sites in the supine and sitting positions, respectively, the inter-site variations in PRV were 4.0% and 3.6% for LF power, 3.8% and 4.7% for HF power, and 18.0% and 17.5% for LF/HF, respectively. Conclusions These suggest that PRV shows not only systemic differences from HRV but also considerable inter-site variations.

Introduction: Photoplethysmography (PPG) has been widely used to assess cardiovascular function. However, few studies have comprehensively investigated the effect of measurement site on PPG waveform characteristics. This study aimed to provide a quantitative comparison on this.Methods: Thirty six healthy subjects participated in this study. For each subject, PPG signals were sequentially recorded for 1 min from six different body sites (finger, wrist under (anatomically volar), wrist upper (dorsal), arm, earlobe, and forehead) under both normal and deep breathing patterns. For each body site under a certain breathing pattern, the mean amplitude was firstly derived from recorded PPG waveform which was then normalized to derive several waveform characteristics including the pulse peak time (Tp), dicrotic notch time (Tn), and the reflection index (RI). The effects of breathing pattern and measurement site on the waveform characteristics were finally investigated by the analysis of variance (ANOVA) with post hoc multiple comparisons.Results: Under both breathing patterns, the PPG measurements from the finger achieved the highest percentage of analyzable waveforms for extracting waveform characteristics. There were significant effects of breathing pattern on Tn and RI (larger Tn and smaller RI with deep breathing on average, both p < 0.03). The effects of measurement site on mean amplitude, Tp, Tn, and RI were significant (all p < 0.001). The key results were that, under both breathing patterns, the mean amplitude from finger PPG was significantly larger and its Tp and RI were significantly smaller than those from the other five sites (all p < 0.001, except p = 0.04 for the Tp of “wrist under”), and Tn was only significantly larger than that from the earlobe (both p < 0.05).Conclusion: This study has quantitatively confirmed the effect of PPG measurement site on PPG waveform characteristics (including mean amplitude, Tp, Tn, and RI), providing scientific evidence for a better understanding of the PPG waveform variations between different body sites.

The energy released by the earthquakes occurred in the seismogenetic area of the southern Kamchatka (Russia) from January 1977 to December 2004, reveals an increase in the peak energy in the period 1992–1999. This increase is related to the occurrence of seven earthquakes with magnitude ranging from 6.9 to 7.7; the first of these earthquakes happened on 2 March 1992 with M=7.1. For many years, hydro-geochemical data have been collected with a mean sampling rate of three days, in the form of the most common ions and gases in the water of deep wells and natural springs of a network operating in the south area of the Kamchatka, where the capital city Petropavlovsk is located. The collected data were analysed and differences in the trend and in the spectral content of some hydro-geochemical parameters at the springs were pointed out before and after the occurrence of the March 1992 earthquake, indicating clear post-seismic effects. Then an evident increase in the Carbon Dioxide and in the Hydrogen content appeared practically at each measurement site during the two-four years preceding the earthquake, so that long term precursors can be claimed. Finally, an anomalous decrease in the Carbon Dioxide content at the springs was revealed two/three months prior the earthquake, as a middle term precursor. The earthquake on March 1992 was the event nearest (90–120 km) to the measurement sites that happened in last thirty years.

Although calibration of a hydrodynamic model depends on the availability of measurement data representing the system behavior, advice for the planning of necessary measurement campaigns for model calibration is scarce. This work tries to address this question of efficient measurement site selection on a network scale for the objective of calibrating a hydrodynamic model case study in Austria. For this, a model-based approach is chosen, as the method should be able to be used before measurement data is available. An existing model is assumed to represent the real system behavior. Based on this extended availability of “measurement data” in every point of the system, different approaches are established to heuristically assess the suitability of one or more pipes in combination as calibration point(s). These approaches intend to find suitable answers to the question of measurement site selection for this specific case study within a relatively short time and with a reasonable computational effort. As a result, the relevance of the spatial distribution of calibration points is highlighted. Furthermore, particular efficient calibration points are identified and further measurement sites in the underlying network are recommended.

Two different South Foehn types have been described in the literature: the Swiss Foehn is characterized by significant ascent on the southern side of the Alps, hence fulfilling a requirement of the thermodynamic Foehn theory associated with latent heating. On contrast, the Austrian Foehn is characterized by near-horizontal flow to the south of the Alps, followed by dry-adiabatic descent into the northern Foehn valleys. In this study, we make use of three years (2000–2002) of NWP reanalysis data, based on the COSMO model, and corresponding Foehn observations at a Swiss (Altdorf in the Reuss Valley) and Austrian (Ellbögen in the Wipp Valley) measurement site to address the applicability of this Foehn type classification. First, the methods are introduced in a case study of a strong Foehn case on 2–4 April 2000. The more traditional Eulerian analysis is complemented by trajectory calculations. Forward trajectories started in the Po Valley and backward trajectories started at the two Foehn stations reveal a complex flow situation. For instance, air parcels arriving in Altdorf can be trapped in the easterly, low-level Po Valley jet before ascending and passing over the Alpine crest, thus originating from further east than air parcels arriving in Ellbögen and having experienced less vertical ascent south of the Alps. This highlights the potential of Lagrangian-based flow analysis and concurrently points to the limitations of a pure Eulerian perspective.The main part of the study considers a climatology of the 3-year backward trajectories started at Altdorf and Ellbögen. Some key findings are: (i) a larger fraction of trajectories arriving in Altdorf experience substantial lifting on the Alpine south side compared to Ellbögen; (ii) both Foehn types can be observed at both stations, i.e., the type naming cannot be taken as an exclusive regional classification; (iii) precipitation traced back is more predominant for Altdorf trajectories than for Ellbögen ones, indicating that the latent heating contributes more to Foehn warming in Altdorf than in Ellbögen. Finally, from a forecasting perspective it is of interest whether the Foehn type can be deduced from a simple measurement alone. To this aim, Milan pseudo-soundings in the Po Valley, essentially south of Altdorf, are considered. Composite soundings are compared for Foehn cases in Altdorf with substantial lifting to those with weak lifting, corresponding to a non-blocked and blocked flow in the Po Valley. The two classes clearly differ in their composite profile; however, the spread prohibits an immediate classification on this sounding alone., Meteorologische Zeitschrift, 24 (3), ISSN:0941-2948, ISSN:1610-1227

Seasonal and spatial patterns of extremely high beryllium-7 surface concentration recorded over the 2001-2010 period across Europe are investigated. The beryllium-7 measurements for 14 sites are taken from the Radioactivity Environmental Monitoring Database. The maxima and minima in the annual cycle of the beryllium-7 surface concentration occur later in the year as the latitude of the measurement site decreases. Extremely high beryllium-7 surface concentrations are defined here as values greater than the 95th percentile in each measurement site. Most of the extremes occur over the March-August period. At least 10 % of the total number of extremes appear during autumn and winter, with an exception of Vienna, where all the extremes took place during spring and summer. The regional spread of extremes common to pairs of measurement sites points to an existence of three distinct regions in Europe: north of 55°N, between 45°N and 55°N, and south of 45°N. Although the beryllium-7 concentration records are significantly correlated across all the investigated sites, the strongest correlations are found within the identified regions. Sezonska i prostorna raspodela ekstremno visokih specifičnih aktivnosti berilijuma-7 u prizemnom sloju atmosfere analizirane su u ovom radu. Merenja tokom 2001-2010. godine na 14 evropskih stanica preuzeta su iz REMdb-baze podataka Monitoring radioaktivnosti u životnoj sredini. Prvo su razmotreni godišnji ciklusi specifične aktivnosti berilijuma-7 koji pokazuju da se godišnje maksimalne i minimalne srednje mesečne vrednosti pomeraju ka kasnijim mesecima kako se smanjuje geografska širina merne stanice. Za ekstremno visoke vrednosti specifične aktivnosti berilijuma-7 uzete su vrednosti veće od 95-og percentila, koji je izračunat za svaku stanicu posebno. Najveći broj ovih ekstrema događa se od marta do avgusta, a najmanje 10 % od ukupnog broja ekstrema tokom jeseni i zime. Izuzetak je merna stanica Beč na kojoj su se svi ekstremi dogodili tokom proleća i leta. Rasprostranjenost ekstrema koji su zajednički za parove mernih mesta, ukazuje da postoje tri različita regiona u Evropi: severno od 55°N, između 45°N i 55°N, i južno od 45°N. Iako su merenja specifične aktivnosti berilijuma-7 značajno korelisana za sve analizirane stanice, najveći koeficijenti korelacije dobijeni su u okviru ovih regiona.

Core body temperature (CBT) is an important and commonly used indicator of human health and endurance performance. A rise in baseline CBT can be attributed to an onset of flu, infection or even thermoregulatory failure when it becomes excessive. Sites which have been used for measurement of CBT include the pulmonary artery, the esophagus, the rectum and the tympanic membrane. Among them, the tympanic membrane is an attractive measurement site for CBT due to its unobtrusive nature and ease of measurement facilitated, especially when continuous CBT measurements are needed for monitoring such as during military, occupational and sporting settings. However, to-date, there are still polarizing views on the suitability of tympanic membrane as a CBT site. This paper will revisit a number of key unresolved issues in the literature and also presents, for the first time, a benchmark of the middle ear temperature against temperature measurements from other sites. Results from experiments carried out on human and primate subjects will be presented to draw a fresh set of insights against the backdrop of hypotheses and controversies.

While land use regression models (LUR) are commonly used, e.g. for the prediction of spatially variable air pollutant mass concentrations, they are scarcely used for predicting the oxidative potential (OP), a suggested unifying predictor of health effects. Therefore a LUR model was developed to examine if long-term OP of fine particulate exposure can be reasonably predicted by LUR modeling and whether it is related to health effects in a study region comprised of urban and rural areas. Four 14-day sampling periods over 1 year at 40 sites in the western Ruhr Area and adjacent northern rural area, Germany, in 2002/2003 were conducted and annual Nitrogen Dioxide (NO2), fine particles (PM2.5), and OP were calculated. LUR models were developed to estimate spatially-resolved annual OP, NO2 and PM2.5 concentrations. The model performance was checked by leave-one-out cross validation (LOOCV) and cox regression was used to analyze the association of modeled residential OP and NO2 with incident type 2 diabetes mellitus (T2DM) in 1784 elderly women during a mean follow-up of 16 years (baseline 1985–1994). The measured OP and NO2 concentrations were moderately correlated (rSpearman 0.57). The LUR models explained 62% and 92% of the OP and NO2 variance (adjusted LOOCV R2 57% and 90%). PM10 emission from combustion in a 5000 m buffer was the most important predictor for OP and NO2. Modeled pollutants were highly correlated (rSpearman 0.87). Model quality for OP was sensitive to the inclusion of a single influential measurement site. For PM2.5 mass only an insufficient model with a low explained variance of 22% (adjusted R2) was developed so no health effects analyses were conducted with estimated PM2.5. Increases in OP and NO2 were associated with an increase in risk of T2DM by a hazard ratio of 1.38 (95% CI 1.06–1.80) and 1.39 (95% CI 1.07–1.81) per interquartile range of OP and NO2, respectively. We conclude that spatially-resolved OP can be predicted by LUR modeling, but future work is needed to investigate the possibility to increase OP model quality with refined predictors.

Objective: To compare the means and changes over time of intra-abdominal fat (IAF) and subcutaneous abdominal fat (SAF) measured by abdominal ultrasound (US) and computerized tomography (CT).Design and Methods: Prospective cohort study of 53 women with obesity and infertility undergoing a lifestyle program.Results: The Pearson's correlation between IAF measurement by US compared to CT was good at baseline, month 3 and 6 (all r >= 0.72). The correlation of SAF measurement by US compared to CT was reasonable at baseline (r = 0.54; 95%CI 0.30-0.78) and weak at month 3 and 6 (all r 0.48). US could not measure the changes of SAF over time. The Bland-Altman plot showed good agreement between US and CT for IAF measurements (-1.1 [95%CI - 3.9-1.6] cm lower mean in US) at baseline. For changes of IAF over time, mean estimates were in agreement.Conclusion: In women with obesity and infertility, measuring IAF by US is in good agreement with the CT scan methodology but the measurement of SAF by US is unreliable.

Industrial activity is a major source of sulphur compound emissions. The sulphuric acid and sulphur dioxide measurements in the vicinity of the industrial area and the oil refinery in Kilpilahti expressed great variation in concentration. The hourly mean values of concentration were categorized according to the area from where the air mass was travelling towards the measurement site. The statistical characteristics and diurnal behavior of emissions between these areas were significantly different.

Aerosol physical and optical properties were measured at two locations in northern India. The first measurement station was a background site in Mukteshwar, about 350 km northeast of New Delhi, in the foothills of the Indian Himalayas, with data from 2006 to 2009. The second measurement site was located in Gual Pahari, about 25 km south of New Delhi, with data from 2008 to 2009. At both stations, the average aerosol concentrations during the monsoon were decreased by 40–75 % compared to the pre-monsoon average concentrations. The decrease varied with the total local rainfall. In Mukteshwar, the monsoon season removed particles from all size classes, due to a combination of rain scavenging and activation to cloud and mountain fog droplets. The scavenging by rain is least effective for the size range of the accumulation mode particles. In Gual Pahari, this was the only major wet removal mechanism and, as a result, the accumulation mode particles were less effectively removed. Aerosol concentrations during the early monsoon were found to be affected by mineral dust which in Gual Pahari was observed as an increased particle volume at a diameter around 3–4 μm. The single scattering albedo varied from 0.73 to 0.93 during the monsoon season, being slightly lower in Gual Pahari than in Mukteshwar. This is due to the fact that Gual Pahari resided closer to high anthropogenic black carbon emissions. As the absorbing particles are typically in the accumulation mode, they were not effectively removed by rain scavenging. The aerosol columnar properties, which were measured in Gual Pahari, showed a somewhat different seasonal behaviour compared to the surface measurements, with the aerosol optical depth increasing to an annual maximum in the early monsoon season.

In situ measurements of the mass concentration of black carbon (BC) and mixing ratios of carbon monoxide (CO) and carbon dioxide (CO2) were made at Guangzhou, an urban measurement site in the Pearl River Delta (PRD), China, in July 2006. The average ± standard deviation (SD) concentrations of BC, CO, and CO2 were 4.7± 2.3 μgC m−3, 798± 459 ppbv, and 400± 13 ppmv, respectively. The trends of these species were mainly controlled by synoptic-scale changes in meteorology during the campaign. Based on back trajectories, data are analyzed separately for two different air mass types representing northerly and southerly flows. The northerly air masses, which constituted ~25% of the campaign, originated mostly in the PRD and hence represent observations on regional scales. On the other hand, during southerly flow (~75%), the measurements were influenced by dilution due to cleaner marine air. The diurnal patterns of BC, CO, and CO2 exhibited peak concentrations during the morning and evening hours coinciding with rush-hour traffic. The ratios of OC/BC were lower during the morning hour peaks in the concentrations of primary pollutants due to their fresh emissions mainly from vehicular traffic in Guangzhou. The diurnal variations of BC observed in southerly air masses tended to follow the traffic patterns of heavy-duty vehicles (HDV) in Guangzhou, while the roles of other sources need to be investigated. The slopes of ΔBC/ΔCO, ΔBC/ΔCO2, and ΔCO/ΔCO2 observed during northerly flows were 0.0045 μgC m−3/ppbv, 0.13 μgC m−3/ppmv, and 49.4 ppbv/ppmv, respectively, agreeing reasonably with their respective emission ratios derived from regional emission inventories.

We present net emission estimates of CH4 and N2O of The Netherlands based on measurements conducted during the period of May 2006 to April 2009 at station Lutjewad, The Netherlands (6°21' E, 53°24' N, 1 m a.s.l.). 222Radon mixing ratios were applied as an indicator for vertical mixing and long-range air mass transport and used to calculate the net surface fluxes from atmospheric mixing ratios of CH4 and N2O. Our study shows that our measurement site Lutjewad is well-suited to measure emissions from The Netherlands and validation of the national inventories using the 222Radon flux method. Since this study is purely observation-based it is independent from inventories or atmospheric models. Our results are compared to the national inventories as reported to the UNFCCC. We found net emissions of: (15.2±5.3) t km−2 a−1 for CH4 and (0.9±0.3) t km−2 a−1 for N2O. These values are lower than the inventory-based emissions (2006-2008 averages) of (18.3±3.3) t km−2 a−1 for CH4, and (1.3±0.6) t km−2 a−1 for N2O, but the differences are insignificant.

Objective: To compare the means and changes over time of intra-abdominal fat (IAF) and subcutaneous abdominal fat (SAF) measured by abdominal ultrasound (US) and computerized tomography (CT). Design and Methods: Prospective cohort study of 53 women with obesity and infertility undergoing a lifestyle program. Results: The Pearson's correlation between IAF measurement by US compared to CT was good at baseline, month 3 and 6 (all r >= 0.72). The correlation of SAF measurement by US compared to CT was reasonable at baseline (r = 0.54; 95%CI 0.30-0.78) and weak at month 3 and 6 (all r 0.48). US could not measure the changes of SAF over time. The Bland-Altman plot showed good agreement between US and CT for IAF measurements (-1.1 [95%CI - 3.9-1.6] cm lower mean in US) at baseline. For changes of IAF over time, mean estimates were in agreement. Conclusion: In women with obesity and infertility, measuring IAF by US is in good agreement with the CT scan methodology but the measurement of SAF by US is unreliable.

To better assess Biogenic Volatile Organic Compounds (BVOC) ambient levels and understand the processes undergone during their transport, a 1-month intensive measurement campaign, involving the monitoring of more than 80 species including isoprenoids (isoprene and 6 monoterpenes), took place in summer 2009 at the remote site of Peyrusse-Vieille, France. The simultaneous study of monoterpenes and isoprene temporal evolution and meteorological parameters underline two different behaviors, which can be associated to different kind of emissions sources. Thus, isoprene displays characteristics usually associated to local emissions sources; whereas monoterpenes temporal trends would more likely be related to distant ones. Subsequent dispersion models and reactivity studies demonstrated that monoterpenes principally result from the influence of an important regional BVOC emitter: the Landes' forest (70 km North-west to the measurement site). Emissions from Landes forest strongly impact the atmospheric reactivity at the measurement site. Thus, when the measurement site is under the forest's plume (Western wind episodes), HO -initiated processes are predominant; whereas O3-induced oxidation processes are observed in other circumstances (north-eastern winds episodes). This dichotomy can be explained by higher in-situ reactivity induced by the upcoming of BVOC from distant sources.

Variability in peripheral quantitative computed tomography (pQCT) measurement sites and outcome variables limit direct comparisons of results between studies. Furthermore, it is unclear what estimates of bone strength are most indicative of changes due to aging, disease, or interventions. The purpose of this study was to examine age and sex differences in estimates of tibia strength. An additional purpose of this study was to determine which tibia site or sites are most sensitive for detecting age and sex differences in tibia strength. Self-identifying Caucasian men (n=55) and women (n=59) aged 20-59yr had their tibias measured with pQCT from 5% to 85% of limb length in 10% increments distal to proximal. Bone strength index, strength strain index (SSI), moments of inertia (Ip, Imax, and Imin), and strength-to-mass ratios (polar moment of inertia to total bone mineral content [BMC] ratio [Ip:Tot.BMC] and strength strain index to total BMC ratio [SSI:Tot.BMC]) were quantified. There were significant (p0.01) site effects for all strength variables and strength-to-mass ratios. Site×sex interaction effects were significant (p0.05) for all strength variables. Men had greater (p0.01) values than women for all strength variables. Sex differences in Ip, Imax, Ip:Tot.BMC, SSI, and SSI:Tot.BMC ratios were the smallest at the 15% site and peaked at various sites, depending on variable. Site×age interactions existed for Imax, Ip:Tot.BMC, and SSI:Tot.BMC. There were significant age effects, Imax, Ip:Tot.BMC, and SSI:Tot.BMC, as values were the lowest in the 20-29 age group. Age and sex differences varied by measurement site and variable, and larger sex differences existed for moments of inertia than SSI. Strength-to-mass ratios may reflect efficiency of the whole bone architecture.

11 pags, 6 figs, Simultaneous measurements of atomic iodine (I), molecular iodine (I 2) and ultrafine particles were made at O Grove, Galicia (42.50° N, 8.87° W), on the northwest coast of Spain. The observations show a strong tidal signature, and indicate that the most probable sources of reactive iodine species are the exposed macroalgae during low tide. For the first time, I 2 and I were concurrently measured revealing a high average I2/I ratio of ∼32, which is higher than previously inferred by modelling studies. A 1-dimensional photochemical model is employed to simulate the observations showing that the high I2/I ratio can be reproduced in the presence of fast vertical mixing close to the surface, or using an extra chemical loss for I atoms with an unknown species. There is a lack of strong correlation between the I2/I and ultrafine particles, indicating that although they both have macroalgal sources, these were not at the same location. The model simulations also suggest that the source of the observed ultrafine particles is likely not very close to the measurement site, in order for the particles to form and grow, but the source for I and I2 must be local. Finally, the effect of NOx levels on iodine oxides, and the conditions under which iodine particle bursts will be suppressed, are explored. © 2011 Author(s)., The authors thank Rolando Argibai and Marisol Garcia for logistical support during the campaign. We are grateful to T. Ingham for instrumental support and helpful comments. This work was funded by the Spanish Research Council (CSIC) and the Regional Government of Castilla-La-Mancha (FGMACLM).

Accurate measures of visceral and abdominal subcutaneous fat are essential for investigating the pathophysiology of obesity. Classical anthropometric measures such as waist and hip circumference cannot distinguish between these two fat depots. Direct imaging methods such as computed tomography and magnetic resonance imaging (MRI) are restricted in large-scale studies due to practical and ethical issues. We aimed to establish whether ultrasound is a valid alternative method to MRI for the quantitative assessment of abdominal fat depots in older individuals. The study population comprised 74 white individuals (41 men and 33 women, aged 67-76 years) participating in the Hertfordshire Birth Cohort Physical Activity trial. Anthropometry included height, weight, waist and hip circumferences. Abdominal fat was measured by ultrasound in two compartments: visceral fat defined as the depth from the peritoneum to the lumbar spine; and subcutaneous fat defined as the depth from the skin to the abdominal muscles and compared to reference measures by MRI (10-mm single-slice image). Ultrasound measures were positively correlated with MRI measures of visceral and subcutaneous fat (visceral: r = 0.82 and r = 0.80 in men and women, respectively; subcutaneous: r = 0.63 and 0.68 in men and women, respectively). In multiple regression models, the addition of ultrasound measures significantly improved the prediction of visceral fat and subcutaneous fat in both men and women over and above the contribution of standard anthropometric variables. In conclusion, ultrasound is a valid method to estimate visceral fat in epidemiological studies of older men and women when MRI and computed tomography are not feasible.

Background Modern computer tomography (CT) equipment can be used to acquire whole-body data from large animals such as pigs in minutes or less. In some circumstances, computer assisted analysis of the resulting image data can identify and measure anatomical features. The thickness of subcutaneous adipose tissue at a specific site measured by ultrasound, is used in the pig industry to assess adiposity and inform management decisions that have an impact on reproduction, food conversion performance and sow longevity. The measurement site, called "P2", is used throughout the industry. We propose that CT can be used to measure subcutaneous adipose tissue thickness and identify novel measurement sites that can be used as predictors of general adiposity. Methods Growing pigs (N = 12), were each CT scanned on three occasions. From these data the total volume of adipose tissue was determined and expressed as a proportion of total volume (fat-index). A computer algorithm was used to determined 10,201 subcutaneous adipose thickness measurements in each pig for each scan. From these data, sites were selected where correlation with fat-index was optimal. Results Image analysis correctly identified the limits of the relevant tissues and automated measurements were successfully generated. Two sites on the animal were identified where there was optimal correlation with fat-index. The first of these was located 4 intercostal spaces cranial to the caudal extremity of the last rib, the other, a further 5 intercostal spaces cranially. Conclusion The approach to image analysis reported permits the creation of various maps showing adipose thickness or correlation of thickness with other variables by location on the surface of the pig. The method identified novel adipose thickness measurement positions that are superior (as predictors of adiposity) to the site which is in current use. A similar approach could be used in other situations to quantify potential links between subcutaneous adiposity and disease or production traits.

International audience; Background & AimsFibroscan is a noninvasive device that assesses liver fibrosis by liver stiffness evaluation (LSE) with ultrasonographic elastometry. We evaluated LSE reproducibility and its influencing factors. Methods LSE was performed by 4 experienced physicians (>100 LSEs) in 46 patients with chronic liver disease at 4 different anatomic sites. Additional LSEs were performed for ancillary aims, so that 534 LSEs were available. Results Overall interobserver agreement for LSE results was considered as excellent, with intraclass coefficient correlation (Ric) of 0.93. Low LSE level, nonrecommended sites, LSE interquartile range > 25%, and body mass index ≥25 independently decreased agreement. Thus, agreement was fair (Ric = 0.53) for LSE < 9 kilopascals and excellent (Ric = 0.90) beyond. The best measurement site for LSE reproducibility was the median axillary line on the first intercostal space under the liver dullness upper limit, with the patient lying in dorsal decubitus. When LSE results were categorized into fibrosis Metavir stages, interobserver discordance was noticed in about 25% of the cases and was the highest for F2 and F3 stages and the lowest for F4. Intraobserver (Ric = 0.94), intersite (Ric = 0.92–0.98), and interequipment (Ric = 0.92) agreements for LSE results were excellent. Preliminary standard ultrasonography or probe pressure changes did not improve interobserver agreement. Conclusions The best measurement site for LSE is the one generally used for liver biopsy. Reproducibility of LSE is globally excellent but is fair in patient with low liver stiffness. The fibrosis diagnosis by ultrasonographic elastometry in low stages or categorized into fibrosis Metavir stages must be interpreted with caution.

Tibial quantitative ultrasonometry is a relatively novel technique in the field of bone sonometry, an emerging alternative to bone densitometry. The implementation of this technique in a pediatric population could prove valuable from a clinical as well as a research viewpoint. In clinical practice it is necessary to know the precision of this technique and the possible influence on measurements before implementation. This study presents the precision in a Caucasian pediatric population and the influence of measurement site, dexterity, brand of coupling gel, and temperature of coupling gel. To assess intra- and interobserver variance duplicate measurements, with repositioning, ultrasonometry was performed in 10 children over a short period of time. The observers were blinded for the results of the other observer and after each measurement the skin markings were removed. Intraobserver variance for operator one (MHL) and for observer two (SFGR) was CV 0.43%. The interobserver variance was CV 0.61%. Left midtibial and right midtibial speed of sound (SOS) measurements showed no significant differences. There were, however, significant differences in both boys and girls between right proximal versus right midtibial, right midtibial versus right distal, and right proximal versus right distal (for all P < 0.001). One-way analysis of variance (ANOVA) showed that neither the use of different coupling gels nor an increase in gel temperature had a significant influence on measurements. The results of our study show that tibial quantitative ultrasonography (QUS) is a highly reproducible technique in a Caucasian pediatric population.

To assess potential metabolic and microcirculatory alterations in critically ill patients, near-infrared spectroscopy (NIRS) has been used, in combination with a vascular occlusion test (VOT), for the noninvasive measurement of tissue oxygen saturation (StO2), oxygen consumption, and microvascular reperfusion and reactivity. However, the methodologies for assessing StO2 are very inconsistent in the literature and results vary from study to study. In this study we investigated the effects of the probe spacing and measurement site, using both a 15 mm and a 25 mm probe spacing on the thenar and the forearm, in healthy volunteers.

In this study, we applied photoplethysmography (PPG) as an alternative, convenient, and affordable method for bovine heat detection. Heat detection is an essential part of effective herd reproduction management. Currently, there are many different heat detection techniques, but they can be ineffective or impractical to use. Since heat affects local vulvar blood circulation (resulting in swelling and erythema), photoplethysmography could represent an affordable alternative to detect this bovine phenomenon. In this study, we enrolled 20 animals in heat and other stages of the bovine reproduction cycle. We analyzed the PPG signal in terms of baseline (DC component), power, kurtosis, and erythema index. One vaginal measurement site, approximately 8 cm from the vulva, exhibited significant differences in mucous color (PPG green and red baseline, both erythema indices). What is more, cows in heat displayed higher PPG signal power and kurtosis, but differences were not significant. Photoplethysmography exhibited the potential to detect bovine heat.