Designing for climate change: twenty-five design features to improve sanitation technology resilience in low- and middle- income countries.

Unlabelled: Climate change is exacerbating events such as floods and droughts, and trends including sea-level rise, leading to failures in sanitation technologies, increased public health risks and environmental pollution. To reduce these risks, it is crucial to incorporate climate resilience into sanitation technology designs. In this study, we reviewed academic and selected grey literature and identified 25 design features that can contribute to the technology's resilience to an increasingly volatile and extreme climate.

Implementing a scoping review to explore sport officials' mental health.

Introduction: Sport officials are tasked with applying rules, maintaining fairness, and ensuring athlete safety. However, sport officials experience anxiety, burnout, and non-accidental violence, with the incidence of these events increasing worldwide. This has led to rising attrition rates among sport officials, with many sport organizations concerned for their operational capacity.

Can processed images be used to determine the modulation transfer function and detective quantum efficiency?

Purpose: The modulation transfer function (MTF) and detective quantum efficiency (DQE) of x-ray detectors are key Fourier metrics of performance, valid only for linear and shift-invariant (LSI) systems and generally measured following IEC guidelines requiring the use of raw (unprocessed) image data. However, many detectors incorporate processing in the imaging chain that is difficult or impossible to disable, raising questions about the practical relevance of MTF and DQE testing. We investigate the impact of convolution-based embedded processing on MTF and DQE measurements.

Reduced Total Airway Count and Airway Wall Tapering after Three-Years in Ex-Smokers.

Computed tomography (CT) total-airway-count (TAC) and airway wall-thickness differ across chronic obstructive pulmonary disease (COPD) severities, but longitudinal insights are lacking. The aim of this study was to evaluate longitudinal CT airway measurements over three-years in ex-smokers. In this prospective convenience sample study, ex-smokers with ( = 50; 13 female; age = 70 ± 9 years; pack-years = 43 ± 26) and without ( = 40; 17 female; age = 69 ± 10 years; pack-years = 31 ± 17) COPD completed CT, He magnetic resonance imaging (MRI), and pulmonary function tests at baseline and three-year follow-up.

Benzylic deuteration of alkylnitroaromatics via amine-base catalysed exchange with deuterium oxide.

This paper describes the deuterium-labelling of alkylnitroaromatics by base-catalysed exchange with deuterium oxide. As the alkyl protons alpha to the aromatic ring are the most acidic sites in the molecule, regioselective hydrogen isotope exchange at this benzylic location leads to a regiospecifically deuterated product. The exchange labelling takes place in good yields and with high atom% abundance in the presence of an appropriate nitrogen base.

Theoretical comparison of energy-resolved and digital-subtraction angiography.

Background: X-ray coronary angiography is a sub-optimal vascular imaging technique because it cannot suppress un-enhanced anatomy that may obscure the visualization of coronary artery disease.

Purpose: The purpose of this paper is to evaluate the theoretical image quality of energy-resolved x-ray angiography (ERA) implemented with spectroscopic x-ray detectors (SXDs), which may overcome limitations of x-ray coronary angiography.

Methods: We modeled the large-area signal-difference-to-noise (SDNR) of contrast-enhanced vasculature in ERA images and compared with that of digital-subtraction angiography (DSA), which served as a gold standard vascular imaging technique.

Science and practice of imaging physics through 50 years of SPIE Medical Imaging conferences.

: For 50 years now, SPIE Medical Imaging (MI) conferences have been the premier forum for disseminating and sharing new ideas, technologies, and concepts on the physics of MI. : Our overarching objective is to demonstrate and highlight the major trajectories of imaging physics and how they are informed by the community and science present and presented at SPIE MI conferences from its inception to now. : These contributions range from the development of image science, image quality metrology, and image reconstruction to digital x-ray detectors that have revolutionized MI modalities including radiography, mammography, fluoroscopy, tomosynthesis, and computed tomography (CT).

Training and development in sport officials: A systematic review.

Sport officials make significant contributions to organized sport, yet scientific evidence to inform their specialized training and education at various levels has lagged. While psychological and performance demands of expert sport officials have been well documented, the extent of research about talent and expertise development, training efficacy, and broader developmental trajectories is unclear. This systematic review summarizes 30 years of published findings on the study of training and development of sport officials, including areas of research interest, study designs, and sport official characteristics.

Frequency-dependent signal and noise in spectroscopic x-ray imaging.

Purpose: We present a new framework for theoretical analysis of the noise power spectrum (NPS) of photon-counting x-ray detectors, including simple photon-counting detectors (SPCDs) and spectroscopic x-ray detectors (SXDs), the latter of which use multiple energy thresholds to discriminate photon energies.

Methods: We show that the NPS of SPCDs and SXDs, including spatio-energetic noise correlations, is determined by the joint probability density function (PDF) of deposited photon energies, which describes the probability of recording two photons of two different energies in two different elements following a single-photon interaction. We present an analytic expression for this joint PDF and calculate the presampling and digital NPS of CdTe SPCDs and SXDs.

Cascaded systems analysis of charge sharing in cadmium telluride photon-counting x-ray detectors.

Purpose: Single-photon-counting (SPC) and spectroscopic x-ray detectors are under development in academic and industry laboratories for medical imaging applications. The spatial resolution of SPC and spectroscopic x-ray detectors is an important design criterion. The purpose of this article was to extend the cascaded systems approach to include a description of the spatial resolution of SPC and spectroscopic x-ray imaging detectors.

Report of AAPM Task Group 162: Software for planar image quality metrology.

Purpose: The AAPM Task Group 162 aimed to provide a standardized approach for the assessment of image quality in planar imaging systems. This report offers a description of the approach as well as the details of the resultant software bundle to measure detective quantum efficiency (DQE) as well as its basis components and derivatives.

Methods: The methodology and the associated software include the characterization of the noise power spectrum (NPS) from planar images acquired under specific acquisition conditions, modulation transfer function (MTF) using an edge test object, the DQE, and effective DQE (eDQE).

MTF and DQE enhancement using an apodized-aperture x-ray detector design.

Purpose: Acquisition of high-quality x-ray images using low patient exposures requires detectors with high detective quantum efficiency (DQE). We describe a novel apodized-aperture pixel (AAP) design that increases high-frequency modulation transfer function (MTF) and DQE values. The AAP design makes a separation of physical sensor elements from image pixels by using very small sensor elements (e.

Custom database development and biomarker discovery methods for MALDI-TOF mass spectrometry-based identification of high-consequence bacterial pathogens.

A high-quality custom database of MALDI-TOF mass spectral profiles was developed with the goal of improving clinical diagnostic identification of high-consequence bacterial pathogens. A biomarker discovery method is presented for identifying and evaluating MALDI-TOF MS spectra to potentially differentiate biothreat bacteria from less-pathogenic near-neighbour species.

Energy subtraction angiography is comparable to digital subtraction angiography in terms of iodine Rose SNR.

Purpose: X-ray digital subtraction angiography (DSA) is widely used for vascular imaging. However, motion artifacts render it largely unsuccessful for some applications including cardiac imaging. Dual-energy imaging using fast kV switching was proposed in the past to provide the benefits of DSA with fewer motion artifacts, but image quality was inferior to DSA.

Fourier Analysis of Noise Characteristics in Cone-Beam Microtomography Laboratory Scanners.

Goal: We investigate the signal and noise performance of an x-ray microtomography system that incorporates a complementary metal-oxide-semiconductor flat-panel detector as a projection image receptor.

Methods: Signal and noise performance is analyzed in the Fourier domain using modulation-transfer function (MTF), noise-power spectrum (NPS), and noise-equivalent number of quanta (NEQ) with respect to magnification and different convolution kernels for image reconstruction.

Results: Higher magnification provides lower NPS, and thus, higher NEQ performance in the transaxial planes from microtomography.

Theoretical and Monte Carlo optimization of a stacked three-layer flat-panel x-ray imager for applications in multi-spectral medical imaging.

We propose a new design of a stacked three-layer flat-panel x-ray detector for dual-energy (DE) imaging. Each layer consists of its own scintillator of individual thickness and an underlying thin-film-transistor-based flat-panel. Three images are obtained simultaneously in the detector during the same x-ray exposure, thereby eliminating any motion artifacts.

Pulmonary Artery Abnormalities in Ex-smokers with and without Airflow Obstruction.

Pulmonary vascular disease is a common complication of chronic obstructive pulmonary disease (COPD), and an important risk factor for COPD exacerbations and death. We explored the relationship between pulmonary artery volumes measured using thoracic computed tomography (CT) and lung structure-function measured using spirometry, CT and magnetic resonance imaging (MRI) in 124 ex-smokers with (n = 68) and without (n = 56) airflow obstruction, and a control group of 35 never-smokers. We observed significantly greater main (p = .

Detective quantum efficiency of photon-counting x-ray detectors.

Purpose: Single-photon-counting (SPC) x-ray imaging has the potential to improve image quality and enable novel energy-dependent imaging methods. Similar to conventional detectors, optimizing image SPC quality will require systems that produce the highest possible detective quantum efficiency (DQE). This paper builds on the cascaded-systems analysis (CSA) framework to develop a comprehensive description of the DQE of SPC detectors that implement adaptive binning.

Analytic model of energy-absorption response functions in compound X-ray detector materials.

The absorbed energy distribution (AED) in X-ray imaging detectors is an important factor that affects both energy resolution and image quality through the Swank factor and detective quantum efficiency. In the diagnostic energy range (20-140 keV), escape of characteristic photons following photoelectric absorption and Compton scatter photons are primary sources of absorbed-energy dispersion in X-ray detectors. In this paper, we describe the development of an analytic model of the AED in compound X-ray detector materials, based on the cascaded-systems approach, that includes the effects of escape and reabsorption of characteristic and Compton-scatter photons.

Computed tomography density histogram analysis to evaluate pulmonary emphysema in ex-smokers.

Rationale And Objectives: High-resolution computed tomography (CT) measurements of emphysema typically use Hounsfield unit (HU) density histogram thresholds or observer scores based on regions of low x-ray attenuation. Our objective was to develop an automated measurement of emphysema using principal component analysis (PCA) of the CT density histogram.

Materials And Methods: Ninety-seven ex-smokers, including 53 subjects with chronic obstructive pulmonary disease (COPD) and 44 asymptomatic subjects (AEs), provided written informed consent to imaging as well as plethysmography and spirometry.

Cascaded-systems analyses and the detective quantum efficiency of single-Z x-ray detectors including photoelectric, coherent and incoherent interactions.

Purpose: Theoretical models of the detective quantum efficiency (DQE) of x-ray detectors are an important step in new detector development by providing an understanding of performance limitations and benchmarks. Previous cascaded-systems analysis (CSA) models accounted for photoelectric interactions only. This paper describes an extension of the CSA approach to incorporate coherent and incoherent interactions, important for low-Z detectors such as silicon and selenium.

The detective quantum efficiency of photon-counting x-ray detectors using cascaded-systems analyses.

Purpose: Single-photon counting (SPC) x-ray imaging has the potential to improve image quality and enable new advanced energy-dependent methods. The purpose of this study is to extend cascaded-systems analyses (CSA) to the description of image quality and the detective quantum efficiency (DQE) of SPC systems.

Methods: Point-process theory is used to develop a method of propagating the mean signal and Wiener noise-power spectrum through a thresholding stage (required to identify x-ray interaction events).

Emendation of the description of the species Corynebacterium propinquum to include strains which produce urease.

Corynebacterium propinquum is a Gram-positive rod occasionally recovered from clinical infections which, according to 16S rRNA gene sequencing, is most closely related (>99% sequence similarity) to Corynebacterium pseudodiphtheriticum. The two species are very similar biochemically, commonly differentiated by a single test, the detection of urease, where strains of C. propinquum are described as being urease-non-producing and strains of C.