Absolute Measurements Research Articles

Unexpectedly high variability in determining tumour extent in prostatic biopsies: implications for active surveillance.

Tumour content in prostatic biopsies is an important indicator of prostate cancer volume and patient prognosis. Consequently, guidelines typically recommend reporting it as a percentage or linear length (mm). This study aimed to determine the current practices for reporting tumour content in prostatic biopsies and evaluated the consistency among pathologists in diagnosing 10 standard biopsy cases of prostate cancer to assess interobserver variability. A web-based survey gathered data on demographics, experience and attitudes regarding the reporting of prostate cancer and its extent in biopsies. Virtual microscopy allowed analysis of 10 biopsy cases, each consisting of a single slide of prostate cancer. Self-reports from 304 participants recruited via the International Society of Urological Pathology and the German Society of Pathology were analysed. Most participants (43.4%) reported tumour extent as percentage of the biopsy core, 37.6% reported percentages and mm and 18.3% reported mm exclusively. The methods used to determine percentages showed an unexpected spread of choices, leading to considerable variability in results. Additionally, 40.8% of participants took part in the practical segment of the survey. The reported measures of tumour extent confirmed a notable interobserver variability, which was significantly higher for reported percentages. A high rate of interobserver variability in reporting tumour content in prostatic biopsies was found. This matter is especially critical for patients who are candidates for active surveillance. Reporting absolute measures of tumour content has the advantage of lower variability in comparison to percentages.

Development of patient-specific pre-treatment verification procedure for FLASH proton therapy based on time resolved film dosimetry.

Pre-clinical studies demonstrate that delivering a high dose at a high dose rate result in less toxicity while maintaining tumor control, known as the FLASH effect. In proton therapy, clinical trials have started using 250MeV transmission beams and more trials are foreseen. A novel aspect of FLASH treatments, compared to conventional radiotherapy, is the importance of dose rate next to dose and geometry. Therefore, to ensure the safety and quality of FLASH treatments, patient-specific dose-rate verification before treatment is an important additional prerequisite. Various definitions of dose rate have been reported, however, the scanning proton beam (PBS) dose rate definition of Folkerts 2020 is currently the most used. It is the ratio between delta dose (ΔD) and delta time (Δt), subject to a predefined threshold, for a given position. Gafchromic film is a widely available detector used to perform relative and absolute integrated dose measurements. Since the response time of film is in the order of micro seconds it could also be suitable for pre-treatment verification of FLASH proton therapy. Development of a patient-specific pre-treatment verification procedure for FLASH proton therapy based on time resolved film dosimetry. The detector design is presented and validated using three tests. A dedicated setup was built that holds a Gafchromic film and a high-speed camera to record the film during the irradiations. The red color channel of the camera's readings was converted into optical density (OD) and an OD-to-dose calibration curve was applied to determine the relative dose accumulation over time. To undo the film measurement (film response) of the post-irradiation coloration process, it is assumed that each dose deposit (pulse) results in a similar film response function. The convolution of the film response function over the pulse provides the film response. First the film response function was obtained by fitting this parameter onto a known film response and corresponding pulse. Post-irradiation coloration correction was performed by deconvoluting all film measurement by the obtained film response function. From the integral of each measured pulse, the Δt was obtained. Several validation tests were conducted: compare the Δt film measurement to a reference detector, exclude that revisiting spots result in an unwanted artefact on the dose accumulation measurement and thereby Δt, and compare Δt distributions of film measurement and simulation (local gamma evaluation, criteria 10%/2 mm) for nine QA fields (dose values; 12, 15, and 20Gy, and, nozzle currents; 25, 120, and 215nA). A similar analysis was performed for three dose optimized treatment beams, with and without scan patterns optimized on local dose rate. Good agreement was found for Δt comparing film to the reference detector, but for Δt values smaller than ∼20ms the error becomes larger (≥15%). Dose accumulation measured with film over time from a single spot is independent of whether the dose is delivered at once, twice or thrice. All gamma evaluations resulted in a gamma pass rate of ≥90%. Time resolved film dosimetry to perform patient-specific pre-treatment verification in FLASH proton therapy is feasible.

Effects of 12 weeks of futsal training on the body composition and physical performance in students-athletes

The aim of this study was to analyze the effect of futsal training on variables related to body composition and physical performance in student-athletes. This longitudinal study was based on a 12-week training program, and the sample consisted of 34 futsal players in the U17 and U19 categories, competing in a regional championship 2023-2024. The players trained for 240 minutes a week, divided into three training sessions. Body composition (BC) was assessed by measuring skinfolds using an adipometer, and the Futsal Intermittent Endurance Test (FIET) was applied. The Shapiro-Wilk test was used, and the pre- and post-intervention values were analyzed using the Wilcoxon test. The differences were classified according to the effect size for the Wilcoxon test (r). In terms of body composition, height showed a significant increase with a large effect (p<0.01) after the 12 weeks of training, as did body mass (p<0.01) and lean mass (p<0.01). On the other hand, fat mass showed a significant and large-effect reduction in both absolute (p<0.01) and relative (p<0.01) measures. Regarding physical performance, peak velocity showed a significant increase with a large effect (p<0.01), and the FIET distance showed the same tendency (p<0.01). The findings of the present study indicate significant and beneficial changes in both anthropometric measures and physical performance parameters in U17 and U19 athletes after a 12-week futsal training program.

Quantifying Inequalities in Childhood Immunization Using Summary Measures of Health Inequality: An Application of WHO Stata and R ‘Healthequal’ Packages

Background: Monitoring immunization inequalities is crucial for achieving equity in vaccine coverage. Summary measures of health inequality provide a single numerical expression of immunization inequality. However, the impact of different summary measures on conclusions about immunization inequalities has not been thoroughly studied. Methods: We used disaggregated data from household surveys conducted in 92 low- and middle-income countries between 2013 and 2022. Inequality was assessed for two indicators of childhood immunization coverage [three doses of combined diphtheria, tetanus, and pertussis (DTP) vaccine and non-receipt of DTP vaccine or “zero-dose”] across three dimensions of inequality (place of residence, economic status, and subnational region). We calculated 16 summary measures of health inequality and compared the results. Results: These measures of inequality showed more similarities than differences, but the choice of measure can affect inequality assessment. Absolute and relative measures sometimes produced differing results, showing the importance of using both types of measures when assessing immunization inequality. Outliers influenced differences and ratios, but the effect of outlier estimates was moderated through the use of complex measures, which consider all subgroups and their population sizes. The choice of appropriate complex measure depends on the audience, interpretation, and outlier sensitivity. Conclusions: Summary measures are useful for assessing changes in inequality over time and making comparisons across different geographical areas and vaccines, but assumptions and value judgements made when selecting summary measures of inequality should be made explicit in research.

Absolute depth-resolved optic axis measurement with catheter-based polarization sensitive optical coherence tomography

Imaging depth-resolved birefringence and optic axis orientation with polarization sensitive optical coherence tomography (PS-OCT) unveils details of tissue structure and organization that can be of high pathophysiologic, mechanistic, and diagnostic value. For catheter-based PS-OCT, the dynamic rotation of the fiber optic probe, in addition to the polarization effects of the system components, complicates the reliable and robust reconstruction of the sample’s optic axis orientation. Addressing this issue, we present a new method for the reconstruction of absolute depth-resolved optic axis orientation in catheter-based PS-OCT by using the intrinsic retardance of the protecting catheter sheath as a stable guide star signal. Throughout the paper, we rigorously inspect the retardance and optic axis orientation of the sheath and validate our method by imaging a birefringent phantom with known optic axis orientation. Reconstructing the optic axis orientation of the phantom, placed at different locations around the catheter, we measured an average absolute deviation (AAD) for the mean optic axis orientation over cross-sectional images of 3.28°, even with significant bending stress on the catheter. This corresponds to an almost three-fold improvement compared to our earlier method (optic axis AAD of 9.41°). We finally highlight the capability of our reconstruction with stereotactic catheter-based PS-OCT of a fresh sheep brain.

Growth across Grades and Common Item Grade Alignment in Vertical Scaling Using the Rasch Model

AbstractVertical scales are frequently developed using common item nonequivalent group linking. In this design, one can use upper‐grade, lower‐grade, or mixed‐grade common items to estimate the linking constants that underlie the absolute measurement of growth. Using the Rasch model and a dataset from Curriculum Associates’ i‐Ready Diagnostic in math in grades 3–7, we demonstrate how grade‐to‐grade mean differences in mathematics proficiency appear much larger when upper‐grade linking items are used instead of lower‐grade items, with linkings based on a mixture of items falling in between. We then consider salient properties of the three calibrated scales including invariance of the different sets of common items to student grade and item difficulty reversals. These exploratory analyses suggest that upper‐grade common items in vertical scaling are more subject to threats to score comparability across grades, even though these items also tend to imply the most growth.

Economic growth and foreign direct investment in Asia: When investors imperfectly fulfil approved investment plans

Foreign direct investment (FDI) may represent an expansion in the domestic capital supply, which could thus increase GDP growth through the investment and consumption sectors and generate productivity increases. We examine this hypothesis by looking earlier in the investment process and use little-known data on FDI approvals from ten Asian countries that have routinely required advance approval of FDI and have also disclosed this data. We show that the approved FDI predicts actual FDI inflows, and that on average more FDI is approved than realized. The approved FDI is used to create an FDI commitment ratio and gap, which are thus absolute and relative measures of how FDI pledges are fulfilled. We then examine how the host economy is affected by the FDI commitment ratio and gap using an Arellano-Bond dynamic panel estimator to examine an unbalanced dataset spanning 1967–2022. We find GDP growth forecasts are significantly affected by both FDI measures. However, actual GDP growth is affected negatively by the FDI gap, with the effects strongest at the 3-year horizon. Thus, we show that FDI initially displaces domestic capital before expanding the domestic capital supply.

Evaluation of digital radiographic measurements for the diagnosis of acute laminitis.

Traditional radiographic measurements of distal phalanx (Pd) displacement based on the outer hoof wall are not useful for diagnosis of acute laminitis. We hypothesised that the distance between the inner hoof wall and Pd ('lamellar lucent zone'; LLZ) measured on lateromedial digital radiographs would be increased in horses with acute and subacute laminitis compared with healthy horses. Retrospective cohort study and in vivo experimental study. Forelimb radiographs from 32 healthy and 18 laminitic mixed-breed horses were analysed retrospectively. Laminitis was defined by at least two clinical signs (acute multi-limb lameness, increased digital pulse amplitude and/or persistently warm hooves) for ≤3 days (acute), or >3 and ≤14 days (subacute) duration, without overt palmar rotation (≥3°), remodelling, or distal displacement of the Pd. Some laminitic limbs initially classified as acute were subsequently radiographed later in hospitalisation and also included as subacute. Twelve measurements including LLZ at proximal, middle, and distal locations were performed on 126 forelimb radiographs that met the criteria for acute laminitis (n = 39), subacute laminitis (n = 23) or healthy control (n = 64). A mixed effects linear regression model was used for comparisons and a receiver-operator characteristic (ROC) curve was created for select measurements. Three horses were serially radiographed to study the impact of magnification and obliquity. The mean [95% confidence interval] LLZ (mm) was increased in acute and subacute laminitis compared with control in the proximal (acute = 8.8 [8.4-9.2]; subacute = 9 [8-9.9]; control = 7.3 [7-7.7]), middle (acute = 8.9 [8.5-9.3]; subacute = 9.1 [8.2-10]; control = 6.9 [6.5-7.2]), and distal (acute = 9.1 [8.5-9.7]; subacute = 10.2 [9.1-11.3]; control = 7.5 [7.2-7.8]) dorsal lamellar regions (p < 0.001). At a cut-off of >7.5 mm for middle LLZ, sensitivity was 87% [73%-94%] and specificity 91% [81%-96%] for diagnosis of acute laminitis. Using the ratio of middle LLZ to distal phalanx cortical length, sensitivity was 95% [81%-99%] and specificity was 95% [87%-99%] (cut-off >0.11). Magnification and obliquity affected absolute LLZ measurements but did not alter LLZ ratios. No histological confirmation of laminitis. LLZ measurements are potentially useful for radiographic diagnosis of acute and subacute laminitis.

In pursuit of precise Ca ii H K chromospheric surface fluxes. A gravity and temperature dependence

The emission lines of the Ca ii H K doublet present one of the most important channels of radiative cooling for the chromospheres of cool stars. Although most other line emissions ( Mg ii h k and numerous iron lines) populate the far-UV and require a very competitive space-born observing time, the Ca ii H K lines in the optical UV are easily accessible by ground-based spectroscopy with relatively cheap instrumentation, and the observational data are plentiful. At the same time, in order to include realistic mechanical and magnetic heating, advanced chromospheric models now require radiative cooling losses in absolute terms and therefore call for a precise surface flux scale, which could be provided by matching a photospheric Ca ii H K line profile computed by photospheric models. However, a major obstacle here is the significant ambiguity in parameter space in the face of a very sensitive dependence of cool stellar optical UV surface fluxes on the effective temperature. Consequently, we have developed a rigorous method by which precise physical parameters, most notably the effective temperature, are first determined by iSpec tools working on high signal-to-noise spectra and based on a suitable line list and reference continuum. However, crosstalk and navigation of multiple local chi-square minima (best solutions) in parameter space must be considered. Only with the optimal set of parameters is a single phoenix model calculated, which defines the spectral surface flux scale in the Ca ii H K line region. In this paper, we discuss the results of the absolute measurements of Ca ii K line fluxes for 32 representative cool stars and the accuracy of this approach. Finally, we show a comparison of the Ca ii K chromospheric fluxes with line widths, and a relation of chromospheric flux with effective temperature and gravity following the logarithmic form $ F_ Ca II prime prime T_ eff + C^ prime

Method for detection of cerebral blood flow in neurointensive care using longitudinal arterial spin labeling MRI.

Cerebral blood flow (CBF) is carefully monitored in the Neurointensive Care Unit (NICU) to prevent secondary brain insults in patients who have suffered subarachnoid hemorrhage. Including absolute MRI measurements of CBF in the NICU monitoring protocol could add valuable information and potentially improve patient outcomes. This is particularly feasible at Linköping University Hospital, which uniquely has an MRI scanner located in the NICU, enabling longitudinal CBF measurements while eliminating medical transportation risks. Arterial spin labeling is a subtraction-based MRI technique that can measure CBF globally in the brain without the use of contrast agents, and thus is suitable for repeated measurements over short time periods. Therefore, this work aims to develop and implement a methodological workflow for the acquisition, analysis, absolute quantification, and visualization of longitudinal arterial spin labeling MRI measurements acquired in the clinical NICU setting. At this initial stage, the workflow was implemented and tested using acquired test-retest data and longitudinal data from two healthy participants. Subsequently, the workflow was tested in clinical practice on an intubated and ventilated patient monitored in the NICU after suffering a subarachnoid hemorrhage. To ensure accurate day-to-day comparisons between the repeated measurements, the selection of processing and analysis methods aimed to obtain CBF maps in absolute units of ml/min/100g. These CBF maps were quantified using both the FMRIB Software Library and an openly available flow territory atlas. The test-retest data showed small variations (4.4 ml/min/100g between sessions), and the longitudinal measurement resulted in low CBF variability over 12 days. Despite the greater complexity of clinical data, the quantification and chosen visualization tools proved helpful in interpreting the results. In conclusion, this workflow including repeated MRI measurements could help detect changes in CBF between different measurement days and complement other conventional monitoring techniques in the NICU.

Demonstration of magnetically silent optically pumped magnetometers for the TUCAN electric dipole moment experiment

We report the performance of a magnetically silent optically pumped cesium magnetometer with a statistical sensitivity of 3.5 pT/Hz\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sqrt{\ extrm{Hz}}$$\\end{document} at 1 Hz and a stability of 90 fT over 150 s of measurement. Optical pumping with coherent, linearly-polarized, resonant light leads to a relatively long-lived polarized ground state of the cesium vapour contained in a measurement cell. The state precesses at its Larmor frequency in the magnetic field to be measured. Nonlinear magneto-optical rotation then leads to the rotation of the plane of polarization of a linearly polarized probe laser beam. The rotation angle is modulated at twice the Larmor frequency. A measurement of this frequency constitutes an absolute measurement of the magnetic field magnitude. Featuring purely optical operation, non-magnetic construction, low noise floor, and high stability, this sensor will be used for the upcoming TUCAN electric dipole moment experiment and other highly sensitive magnetic applications. Novel aspects of the system include commercial construction and the ability to operate up to 24 sensors on a single probe laser diode.

Development of a chemiluminescent detection method for absolute activity measurement of Taq DNA polymerase through dATP consumption

Being one of the most extensively researched and widely used thermostable DNA polymerases, Taq DNA polymerase derived from Thermus aquaticus has played pivotal roles in numerous molecular biology applications. The accurate and convenient determination of enzymatic activity is a fundamental prerequisite for both academic research and the industrial application of Taq DNA polymerase. To address the limitations of traditional methods for polymerase activity determination, such as low accuracy, complicated operation, and radioactive hazards, we have devised an absolute-quantitation method for Taq DNA polymerase based on chemiluminescence detection of the consumption of dATP (CDC-dATP). The CDC-dATP method offers several advantages, including simplicity suitable for routine laboratory use, high sensitivity (detecting as low as 0.0025 U/μL), excellent reproducibility, a broad linear range for Taq DNA polymerase (0.0025–0.1 U/μL) with a strong linear relationship (R2 > 0.99), and, significantly, absolute activity quantitation without the associated radioactive hazards. We delved into the molecular behavior of Taq DNA polymerase in the CDC-dATP method. Furthermore, we explored the extensive application potential of the CDC-dATP methodology for measuring the activity of various other enzymes involved in dATP/ATP generation or consumption, encompassing other DNA polymerases, reverse transcriptases, RNA polymerases, hydrolases, and protein kinases, covering all seven major categories of enzymes.

Training Load and Injuries in Volleyball: An Approach Based on Different Methods of Calculating Acute to Chronic Workload Ratio.

Many questions persist regarding the relationship between training load and injuries in volleyball, as well as the best method for calculating acute:chronic workload ratio (ACWR). This study aimed to investigate the relationship between different metrics of training load and risk of injury in male professional volleyball players. ACWR, as a training load measure, is useful for identifying injury risk in volleyball players, regardless of calculation method. Longitudinal, prospective, and observational design conducted over 3 seasons of professional male volleyball. Level 3. The study included 43 male volleyball players. Internal training load was quantified using the Session Rating of Perceived Exertion. From daily training load values, absolute measures and relative measures were computed. For relative measures, 7 days were employed for acute training load, and 21 and 28 days for chronic training load. A distinction was made between coupled calculation and uncoupled calculation. Injuries were documented using the Injury Surveillance Form proposed by the International Volleyball Federation. ACWR calculated in a coupled manner and by a rolling average demonstrated higher injury risks when analyzing the complete periods (odds ratio [OR] ACWR 7:28 = 2.040; ACWR 7:21 = 1.980) and competitive period (OR ACWR 7:28 = 2.044; ACWR 7:21 = 2.087). In contrast, during the preseason, the coupled exponential averages were more sensitive to the risk of injury (OR ACWR 7:28 = 4.370; ACWR 7.504). Both measures using rolling averages and those calculated from exponential averages can be employed to identify the risk of injuries in volleyball athletes. The findings of this study can be useful to coaching staff, fitness trainers, and healthcare professionals involved in the challenge of reducing the risk of injury in volleyball athletes. The need for continuous monitoring and real-time adjustments of training load is emphasized.

Adding More Shape to Nanoscale Reference Materials─LiYF4:Yb,Tm Bipyramids as Standards for Sizing Methods and Particle Number Concentration.

The increasing industrial use of nanomaterials calls for the reliable characterization of their physicochemical key properties like size, size distribution, shape, and surface chemistry, and test and reference materials (RMs) with sizes and shapes, closely matching real-world nonspheric nano-objects. An efficient strategy to minimize efforts in producing nanoscale RMs (nanoRMs) for establishing, validating, and standardizing methods for characterizing nanomaterials are multimethod nanoRMs. Ideal candidates are lanthanide-based, multicolor luminescent, and chemically inert nanoparticles (NPs) like upconversion nanoparticles (UCNPs), which can be prepared in different sizes, shapes, and chemical composition with various surface coatings. This makes UCNPs interesting candidates as standards not only for sizing methods, but also for element-analytical methods like laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS), quantitative bioimaging methods like X-ray fluorescence computed tomography (XFCT), and luminescence methods and correlative measurements. Here, we explore the potential of two monodisperse LiYF4:Yb,Tm bipyramids with peak-to-peak distances of (43 ± 2) nm and (29 ± 2) nm as size standards for small-angle X-ray scattering (SAXS) and tools for establishing and validating the sophisticated simulations required for the analysis of SAXS data derived from dispersions of nonspheric nano-objects. These SAXS studies are supplemented by two-dimensional (2D)-transmission electron microscopy measurements of the UCNP bipyramids. Additionally, the particle number concentration of cyclohexane dispersions of these UCNP bipyramids is determined by absolute SAXS measurements, complemented by gravimetry, thermogravimetric analysis (TGA), and inductively coupled plasma optical emission spectrometry (ICP-OES). This approach enables traceable particle number concentration measurements of ligand-capped nonspheric particles with unknown chemical composition.

3D scanner measuring preterm infants’ head circumference and cranial volume: validation in a simulated care setting

IntroductionWeekly head circumference (HC) measurements using a measuring tape is the current standard for longitudinal brain growth monitoring of preterm infants. The MONITOR3D (M3D) 3D scanner has been developed to measure both HC and cranial volume (CrV) of preterm infants within incubators. The M3D’s usability, accuracy and precision were validated in a simulated setting in a neonatal intensive care unit (NICU).Materials and methodsDuring a simulated routine care moment, NICU nurses conducted M3D scans of a preterm doll simulating an extreme low birthweight preterm (ELBW; BW &amp;lt; 1,000 g) infant, followed by manual HC measurements using a measuring tape. Usability was quantified by percentage of successful HC and CrV measurements from scans. HC and CrV were calculated by marking anatomical landmarks on the 3D image. Measurements were compared to the real, ground truth (GT) values of the doll’s head, defined by an accurate medical scanner. Measurement accuracy was assessed using mean or median absolute measurement error (ME), and precision by the spread of ME, represented by the 95% interval of the ME range. ME intervals were compared with preterm weekly growth increases to assess clinical usability.ResultsRegarding usability, 56 M3D scan sessions resulted in 25 successful (44.6%) HC and CrV measurements, with incomplete 3D data being the primary cause of unsuccessful scans. Accuracy of the measuring tape for HC was 0.2 cm (proportional 0.9% of GT), and precision was 1.6 cm (6.3%). M3D’s accuracy of HC was 0.4 cm (1.5%), and precision was 0.7 cm (2.9%). For CrV, M3D’s accuracy was 8.0 mL (3.8%) and precision 22.6 mL (10.8%).ConclusionThe M3D scanner is suitable for measuring HC and CrV in ELBW infants. However, current scan success rate is too low for practical usability. The M3D’s accuracy and precision are clinically sufficient, while the precision of the current measuring tape method is inadequate for preterm infants. This makes the M3D a promising alternative for HC, offering less disturbance to the infant. In the future, the M3D technique could facilitate the creation of CrV growth reference charts for ELBW infants, enhancing the accuracy of clinical growth monitoring for preterm infants.

Single-photon large-momentum-transfer atom interferometry scheme for Sr or Yb atoms with application to determining the fine-structure constant

The leading experimental determinations of the fine-structure constant α currently rely on atomic photon-recoil measurements from Ramsey-Bordé atom interferometry with large-momentum transfer to provide an absolute mass measurement. We propose an experimental scheme for an intermediate-scale differential atom interferometer to measure the photon recoil of neutral atomic species with a single-photon optical clock transition. We calculate trajectories for our scheme that optimize the recoil phase while nullifying the undesired gravity-gradient phase by considering independently launching two clouds of ultracold atoms with the appropriate initial conditions. For Sr and Yb, we find an atom interferometer of height 3 m to be sufficient for an absolute mass measurement precision of Δm/m∼1×10−11 with current technology. Such a precise measurement would halve the current uncertainty in α, an uncertainty that would no longer be limited by an absolute mass measurement. The removal of this limitation would allow the current uncertainty in α to be reduced by a factor of 10 by corresponding improvements in relative mass measurements, thus paving the way for higher-precision tests of the standard model of particle physics. Published by the American Physical Society 2024

Inter-center comparison of proton range verification prototypes with an anthropomorphic head phantom**F. Hueso-González and J. Berthold share first authorship. J. Verburg and C. Richter share last authorship. P. Wohlfahrt was essential for the work conception, treatment planning design and equalization, and for the transatlantic transport of the phantom.

Objective. To compare in reproducible and equalized conditions the performance of two independent proton range verification systems based on prompt gamma-ray detectors from two different proton therapy centers.Approach. An anthropomorphic head phantom with calibrated stopping power, serving as ground truth, was irradiated with comparable treatment plans, spot positions and energies in both facilities. Clinical beam current, tumor contour and dose were used. The absolute range measurement was compared to the expected value according to the ground truth. The statistical precision was assessed by repeating each measurement ten times. Sensitivity to relative range shifts was evaluated by introducing 2 mm and 5 mm plastic slabs on half of the field.Main results. The resulting absolute range accuracy was within 2.4 mm in all cases. Relative range shifts were detected with deviations lower than 14%.Significance. The performance of both systems was deemed worthy of clinical application for the detection of range deviations. This study represents the first comparison of independent prompt gamma-ray-based proton range verification systems under equalized conditions with realistic treatment fields and beam currents.

Sex Estimation Using Heel-Ball Index: A Metric-Based Comparative Study on Foot and Footprint Dimensions.

Background: Sexual dimorphism plays a vital role in individual identification, and body dimensions can contribute to establishing a biological profile for identification purposes. Aims and Objectives: To determine the reliability of the Heel-Ball Index (HBI) in estimating sex from foot dimensions and footprint dimensions and also to investigate the potential of dimensions and indices, using a standardized value, in estimating sex, from foot dimensions and footprint dimensions. Materials and Methods: In this study, a group of 112 young Indian adults aged 18 to 22, consisting of 56 males and 56 females, was examined. The foot breadth at ball (BBAL) and foot breadth at heel (BHEL) of both feet were measured using sliding digital calipers from foot and footprint dimensions. Results: Significant sexual dimorphism was observed in BBAL, BHEL, and HBI (HBI = BHEL/BBAL × 100) measurements in both feet of both sexes. Conclusion: HBI yielded better accuracy for foot dimensions than footprint dimensions. It was also found that utilizing absolute foot dimensions (BBAL and BHEL) yielded more accurate results in estimating sex compared to the HBI, which is calculated as a ratio of absolute measurements.

Mapping soil moisture across the UK: assimilating cosmic-ray neutron sensors, remotely sensed indices, rainfall radar and catchment water balance data in a Bayesian hierarchical model

Abstract. Soil moisture is important in many hydrological and ecological processes. However, data sets which are currently available have issues with accuracy and resolution. To translate remotely sensed data to an absolute measure of soil moisture requires mapped estimates of soil hydrological properties and estimates of vegetation properties, and this introduces considerable uncertainty. We present an alternative methodology for producing daily maps of soil moisture over the UK at 2 km resolution (“SMUK”). The method is based on a simple linear statistical model, calibrated with 5 years of daily data from cosmic-ray neutron sensors at ∼ 40 sites across the country. The model is driven by precipitation, humidity, a remotely sensed “soil water index” satellite product and soil porosity. The spatial variation in the parameter describing the soil water retention (and thereby the response to precipitation) was estimated using daily water balance data from ∼ 1200 catchments with good coverage across the country. The model parameters were estimated by Bayesian calibration using a Markov chain–Monte Carlo method, so as to characterise the posterior uncertainty in the parameters and predictions. The approach reduces uncertainty by integrating multiple data sources, all of which have weaknesses but together act as a better constraint on the true soil moisture. The model explains around 70 % of the variance in the daily observations with a root-mean-square error of 0.05 m3 m−3, better than results from more complex process-based models. Given the high resolution of the inputs in time and space, the model can predict the very detailed variation in soil moisture which arises from the sporadic nature of precipitation events, including the small-scale and short-term variations associated with orographic and convective rainfall. Predictions over the period 2016 to 2023 demonstrated realistic patterns following the passage of weather fronts and prolonged droughts. The model has negligible computation time, and inputs and predictions are updated daily, lagging approximately 1 week behind real time.

Absolute frequency measurements on the 5s5p3P0 → 5s6d3D1 transition in strontium

We report the first absolute frequency measurements for the 5s5p3P0→5s6d3D1 transition at 394 nm for all the stable strontium isotopes by utilizing repumping induced spectroscopy in a magneto-optical trap. Absolute transition frequency is measured to be 760524409251(25) kHz for Sr88. With reference to Sr88, the isotope shifts are measured to be 91052(35), 54600(33), and 51641(28) kHz for Sr84, Sr86, and Sr87, respectively. We calculate the hyperfine constants A and B for the fermionic isotope Sr87 at kHz level. Furthermore, we perform King plot analysis by combining isotope shifts on the 689-nm transition to our data. Published by the American Physical Society 2024