Simulated low-dose dark-field radiography for detection of COVID-19 pneumonia.

Background: Dark-field radiography has been proven to be a promising tool for the assessment of various lung diseases.

Purpose: To evaluate the potential of dose reduction in dark-field chest radiography for the detection of the Coronavirus SARS-CoV-2 (COVID-19) pneumonia.

Materials And Methods: Patients aged at least 18 years with a medically indicated chest computed tomography scan (CT scan) were screened for participation in a prospective study between October 2018 and December 2020.

Optimizing convolutional neural networks for Chronic Obstructive Pulmonary Disease detection in clinical computed tomography imaging.

We aim to optimize the binary detection of Chronic Obstructive Pulmonary Disease (COPD) based on emphysema presence in the lung with convolutional neural networks (CNN) by exploring manually adjusted versus automated window-setting optimization (WSO) on computed tomography (CT) images. 7194 contrast-enhanced CT images (3597 with COPD; 3597 healthy controls) from 78 subjects were selected retrospectively (01.2018-12.

Speckle tracking phase-contrast computed tomography at an inverse Compton X-ray source.

Speckle-based X-ray imaging (SBI) is a phase-contrast method developed at and for highly coherent X-ray sources, such as synchrotrons, to increase the contrast of weakly absorbing objects. Consequently, it complements the conventional attenuation-based X-ray imaging. Meanwhile, attempts to establish SBI at less coherent laboratory sources have been performed, ranging from liquid metal-jet X-ray sources to microfocus X-ray tubes.

Dark-field radiography for the detection of bone microstructure changes in osteoporotic human lumbar spine specimens.

Background: Dark-field radiography imaging exploits the wave character of x-rays to measure small-angle scattering on material interfaces, providing structural information with low radiation exposure. We explored the potential of dark-field imaging of bone microstructure to improve the assessment of bone strength in osteoporosis.

Methods: We prospectively examined 14 osteoporotic/osteopenic and 21 non-osteoporotic/osteopenic human cadaveric vertebrae (L2-L4) with a clinical dark-field radiography system, micro-computed tomography (CT), and spectral CT.

Point-of-care breath sample analysis by semiconductor-based E-Nose technology discriminates non-infected subjects from SARS-CoV-2 pneumonia patients: a multi-analyst experiment.

Metal oxide sensor-based electronic nose (E-Nose) technology provides an easy to use method for breath analysis by detection of volatile organic compound (VOC)-induced changes of electrical conductivity. Resulting signal patterns are then analyzed by machine learning (ML) algorithms. This study aimed to establish breath analysis by E-Nose technology as a diagnostic tool for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pneumonia within a multi-analyst experiment.

Grating-based phase-contrast computed tomography for breast tissue at an inverse compton source.

The introduction of mammography screening programs has significantly reduced breast cancer mortality rates. Nevertheless, some lesions remain undetected, especially in dense breast tissue. Studies have shown that phase-contrast imaging can improve breast cancer diagnosis by increasing soft tissue contrast.

Kinematics of elongate harvestmen chelicerae: Comparative range of motion analyses in extant Ischyropsalis (Dyspnoi, Opiliones).

Chelicerae, the mouthparts of chelicerates, are essential for food processing. Particularly within harvestmen (Opiliones), some species have greatly elongated their tripartite chelicerae and utilize them for mating behavior, defense, and primarily for predation. We investigated two European species, Ischyropsalis muellneri and Ischyropsalis hellwigii, which occupy different niches (caves, forests), exhibit different feeding ecologies (opportunist, specialist), and first and foremost possess different chelicerae morphologies (long and thin, short and robust).

Beyond bacterial paradigms: uncovering the functional significance and first biogenesis machinery of archaeal lipoproteins.

Lipoproteins are major constituents of prokaryotic cell surfaces. In bacteria, lipoprotein attachment to membrane lipids is catalyzed by prolipoprotein diacylglyceryl transferase (Lgt). However, no Lgt homologs have been identified in archaea, suggesting the unique archaeal membrane lipids require distinct enzymes for lipoprotein lipidation.

Persistence, not avoidance, is associated with low back pain-An observational cohort study.

Background: Low back pain (LBP) is increasingly understood as a long-lasting condition with a variable course. Avoidance and persistence behaviour have been described to mediate pain persistence by potentially linking psychosocial factors and biomechanics. The resulting maladaptive changes in musculoskeletal structures can result in movement control impairment (MCI).

Global Distribution and Diversity of Haloarchaeal pL6-Family Plasmids.

Australian isolates of , a square-shaped haloarchaeon, often harbor small cryptic plasmids of the pL6-family, approximately 6 kb in size, and five examples have been previously described. These plasmids exhibit a highly conserved gene arrangement and encode replicases similar to those of betapleolipoviruses. To assess their global distribution and recover more examples for analysis, fifteen additional plasmids were reconstructed from the metagenomes of seven hypersaline sites across four countries: Argentina, Australia, Puerto Rico, and Spain.

Genome sequence of strain G3, a member of a bacterial consortium capable of polyethylene degradation.

A consortium of landfill bacteria including strain G3 can break down polyethylene, a long-lasting plastic that accumulates in the environment. The complete genome sequence of strain G3 was determined by PacBio and Nanopore sequencing and consists of three circular replicons. Genome-based classification assigned strain G3 to the species .

Iron starvation results in up-regulation of a probable siderophore transporter.

The response of the haloarchaeal model organism to iron starvation was analyzed at the proteome level by data-independent acquisition mass spectrometry. Cells grown in minimal medium with normal iron levels were compared to those grown under low iron conditions, with samples being separated into membrane and cytoplasmic fractions in order to focus on import/export processes which are frequently associated with metal homeostasis. Iron starvation not only caused a severe retardation of growth but also altered the levels of many proteins.

Streak artefact removal in x-ray dark-field computed tomography using a convolutional neural network.

Background: Computed tomography (CT) relies on the attenuation of x-rays, and is, hence, of limited use for weakly attenuating organs of the body, such as the lung. X-ray dark-field (DF) imaging is a recently developed technology that utilizes x-ray optical gratings to enable small-angle scattering as an alternative contrast mechanism. The DF signal provides structural information about the micromorphology of an object, complementary to the conventional attenuation signal.

Feasibility of Dark-Field Radiography to Enhance Detection of Nondisplaced Fractures.

Background Many clinically relevant fractures are occult on conventional radiographs and therefore challenging to diagnose reliably. X-ray dark-field radiography is a developing method that uses x-ray scattering as an additional signal source. Purpose To investigate whether x-ray dark-field radiography enhances the depiction of radiographically occult fractures in an experimental model compared with attenuation-based radiography alone and whether the directional dependence of dark-field signal impacts observer ratings.

Robust Sample Information Retrieval in Dark-Field Computed Tomography With a Vibrating Talbot-Lau Interferometer.

X-ray computed tomography (CT) is a crucial tool for non-invasive medical diagnosis that uses differences in materials' attenuation coefficients to generate contrast and provide 3D information. Grating-based dark-field-contrast X-ray imaging is an innovative technique that utilizes small-angle scattering to generate additional co-registered images with additional microstructural information. While it is already possible to perform human chest dark-field radiography, it is assumed that its diagnostic value increases when performed in a tomographic setup.

Improving Automated Hemorrhage Detection at Sparse-View CT via U-Net-based Artifact Reduction.

Purpose To explore the potential benefits of deep learning-based artifact reduction in sparse-view cranial CT scans and its impact on automated hemorrhage detection. Materials and Methods In this retrospective study, a U-Net was trained for artifact reduction on simulated sparse-view cranial CT scans in 3000 patients, obtained from a public dataset and reconstructed with varying sparse-view levels. Additionally, EfficientNet-B2 was trained on full-view CT data from 17 545 patients for automated hemorrhage detection.

Improving image quality of sparse-view lung tumor CT images with U-Net.

Background: We aimed to improve the image quality (IQ) of sparse-view computed tomography (CT) images using a U-Net for lung metastasis detection and determine the best tradeoff between number of views, IQ, and diagnostic confidence.

Methods: CT images from 41 subjects aged 62.8 ± 10.

High-energy X-ray diffraction experiment employing a compact synchrotron X-ray source based on inverse Compton scattering.

X-ray diffraction (XRD) is an important material analysis technique with a widespread use of laboratory systems. These systems typically operate at low X-ray energies (from 5 keV to 22 keV) since they rely on the small bandwidth of K-lines like copper. The narrow bandwidth is essential for precise measurements of the crystal structure in these systems.

The course of acute low back pain: a community-based inception cohort study.

Introduction: Acute low back pain (LBP) is increasingly recognized for its potential recurrent nature and long-term implications.

Objectives: This community-based inception cohort study aimed to delineate trajectories of acute LBP over one year and investigate associated biopsychosocial variables.

Methods: One hundred seventy-six participants with acute LBP were monitored at 5 follow-up time points over 52 weeks.

Ongoing Laboratory Performance Study on Chemical Analysis of Hydrophobic and Hydrophilic Compounds in Three Aquatic Passive Samplers.

The quality of chemical analysis is an important aspect of passive sampling-based environmental assessments. The present study reports on a proficiency testing program for the chemical analysis of hydrophobic organic compounds in silicone and low-density polyethylene (LDPE) passive samplers and hydrophilic compounds in polar organic chemical integrative samplers. The median between-laboratory coefficients of variation (CVs) of hydrophobic compound concentrations in the polymer phase were 33% (silicone) and 38% (LDPE), similar to the CVs obtained in four earlier rounds of this program.

Multimaterial decomposition in dual-energy CT for characterization of clots from acute ischemic stroke patients.

Background: Nowadays, there is no method to quantitatively characterize the material composition of acute ischemic stroke thrombi prior to intervention, but dual-energy CT (DE-CT) offers imaging-based multimaterial decomposition. We retrospectively investigated the material composition of thrombi ex vivo using DE-CT with histological analysis as a reference.

Methods: Clots of 70 patients with acute ischemic stroke were extracted by mechanical thrombectomy and scanned ex vivo in formalin-filled tubes with DE-CT.

sp. nov., a haloarchaeal species isolated from a bore core drilled in Hubei Province, PR China.

Eight colonies of live microbes were isolated from an extensively surface-sterilized halite sample which had been retrieved from a depth of 2000 m from a salt mine in the Qianjiang Depression, Hubei Province, PR China. The eight colonies, obtained after 4 weeks of incubation, were named JI20-1-JI20-8 and JI20-1 was selected as the type strain. The strains have been previously described, including a genomic analysis based on the complete genome for strain JI20-1 and draft genomes for the other strains.

Correction for X-Ray Scatter and Detector Crosstalk in Dark-Field Radiography.

Dark-field radiography, a new X-ray imaging method, has recently been applied to human chest imaging for the first time. It employs conventional X-ray devices in combination with a Talbot-Lau interferometer with a large field of view, providing both attenuation and dark-field radiographs. It is well known that sample scatter creates artifacts in both modalities.