To investigate the feasibility of semiautomatic quantification of mosaic perfusion and the associations between mosaic perfusion on computed tomography (CT; the ratio of hypoperfused parenchyma to ...the whole lung volume) and haemodynamic parameters through linear regression analysis.
Fifty-eight consecutive patients (mean age 66 years, 28 females) diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH) in General University Hospital, Prague, in 2021 were evaluated retrospectively and underwent both right heart catheterisation and CT pulmonary angiography. The parameters derived from the CT examinations were correlated with the recorded haemodynamic parameters.
A method was developed for semiautomatic detection of hypoperfused tissue from CT using widely available software and a statistically significant correlation was found between the proportion of hypoperfused parenchyma and the mean pulmonary artery pressure (mPAP; R2 0.22; p<0.01) and pulmonary vascular resistance (PVR; R2 0.09; p<0.05).
The developed method facilitates the quantification of mosaic perfusion, which is associated with important haemodynamic parameters (mPAP and PVR) in patients with CTEPH.
•Mosaic perfusion is a sign of chronic thromboembolic pulmonary hypertension.•Newly developed algorithm for quantification of mosaic perfusion of lung parenchyma.•Association between this quantification and important hemodynamic parameters.
The integrated low-level trigger and data acquisition (TDAQ) system of the NA62 experiment at CERN is described. The requirements of a large and fast data reduction in a high-rate environment for a ...medium-scale, distributed ensemble of many different sub-detectors led to the concept of a fully digital integrated system with good scaling capabilities. The NA62 TDAQ system is rather unique in allowing full flexibility on this scale, allowing in principle any information available from the detector to be used for triggering. The design concept, implementation and performances from the first years of running are illustrated.
Although fossil remains show that anatomically modern humans dispersed out of Africa into the Near East ∼100 to 130 ka, genetic evidence from extant populations has suggested that non-Africans ...descend primarily from a single successful later migration. Within the human mitochondrial DNA (mtDNA) tree, haplogroup L3 encompasses not only many sub-Saharan Africans but also all ancient non-African lineages, and its age therefore provides an upper bound for the dispersal out of Africa. An analysis of 369 complete African L3 sequences places this maximum at ∼70 ka, virtually ruling out a successful exit before 74 ka, the date of the Toba volcanic supereruption in Sumatra. The similarity of the age of L3 to its two non-African daughter haplogroups, M and N, suggests that the same process was likely responsible for both the L3 expansion in Eastern Africa and the dispersal of a small group of modern humans out of Africa to settle the rest of the world. The timing of the expansion of L3 suggests a link to improved climatic conditions after ∼70 ka in Eastern and Central Africa rather than to symbolically mediated behavior, which evidently arose considerably earlier. The L3 mtDNA pool within Africa suggests a migration from Eastern Africa to Central Africa ∼60 to 35 ka and major migrations in the immediate postglacial again linked to climate. The largest population size increase seen in the L3 data is 3-4 ka in Central Africa, corresponding to Bantu expansions, leading diverse L3 lineages to spread into Eastern and Southern Africa in the last 3-2 ka.
New data on the production of protons, anti-protons and neutrons in p+p interactions are presented. The data come from a sample of 4.8 million inelastic events obtained with the NA49 detector at the ...CERN SPS at 158 GeV/c beam momentum. The charged baryons are identified by energy loss measurement in a large TPC tracking system. Neutrons are detected in a forward hadronic calorimeter. Inclusive invariant cross sections are obtained in intervals from 0 to 1.9 GeV/c (0 to 1.5 GeV/c) in transverse momentum and from −0.05 to 0.95 (−0.05 to 0.4) in Feynman
x
for protons (anti-protons), respectively.
p
T
integrated neutron cross sections are given in the interval from 0.1 to 0.9 in Feynman
x
. The data are compared to a wide sample of existing results in the SPS and ISR energy ranges as well as to proton and neutron measurements from HERA and RHIC.
New data on the production of charged kaons in p+p interactions are presented. The data come from a sample of 4.8 million inelastic events obtained with the NA49 detector at the CERN SPS at 158 GeV/c ...beam momentum. The kaons are identified by energy loss in a large TPC tracking system. Inclusive invariant cross sections are obtained in intervals from 0 to 1.7 GeV/c in transverse momentum and from 0 to 0.5 in Feynman x. Using these data as a reference, a new evaluation of the energy dependence of kaon production, including neutral kaons, is conducted over a range from 3 GeV to
collider energies.
The term calcium-silicate composite can be recalled several basic building materials. The most common representatives are lime-silicate bricks and autoclaved aerated concrete. It is any material ...based on the reaction of lime and siliceous raw material. In this paper, attention is paid to composites based on autoclaved aerated concrete production technology. Possibilities of lightening the composite utilizing waste expanded perlite as a secondary raw material were investigated without the use of aluminium powder, which is commonly used in aerated concrete technology. Replacements of 10%, 30%, 50%, and 100% waste expanded perlite for sand were used. Based on physico-mechanical properties, and with the assessment of the microstructure, it has been found that up to 50% of the replacement of waste expanded perlite results in a lightening of the composite while increasing the compressive strength.
This paper deals with the problematics of utilization of continuous hydrostatic weighing to monitor the volume changes in research of new building materials. The aim of this paper is to describe the ...abilities of continuous hydrostatic weighing and to present the capabilities and results of measurements made using this method. The volume changes in this paper were measured using the laboratory scales connected to computer. The volume changes were studied on the cement-based composites containing up to 40 wt.% of cement substitution by secondary raw material. The high temperature fly ash, packing glass, foundry sand and slag were used as the cement substitution. This research shows that the continuous hydrostatic weighing produces results comparable to other methods for volume change measuring. Therefore, this method can be used for volume change monitoring without using any economically demanding laboratory equipment.
Our entire planet is filled by communication routes, and as a result of the evolving information technologies, their numbers will continue to grow in the future. Demand for their reliability and ...hence the importance of protecting related technologies from all kinds of interference is increasing as well. Therefore, it is necessary to develop new materials in order to protect these routes against negative influences of the environment such as the atmospheric discharge. The main aim of the research is to develop and verify the properties of the cement composite that can be applied in systems of protection of building structures against lightning strike and overvoltage. The first step in the development of this material was the selection of suitable feedstocks, which by their presence in the newly developed material will increase its electrical conductivity respectively reduce its electrical impedance. For this purpose, a spectrum of potential raw materials with a high content of metals and organic carbon was chosen. By means of a suitably selected set of laboratory methods which consisted of determination of specific surface, impedance and total organic carbon content (TOC), materials with the most suitable properties were selected and their parameters determined also in a cement matrix. In order to realize this goal specimens with each conducive material as filler were created with incorporated copper electrodes. Impedance has been significantly reduced compared to the reference samples. The lowest values in the tens of ohms were obtained from samples containing carbon grit 0.5-4.0. This fact proves that the tested fillers can be used in order to produce electrically conductive cement composites.
Summary
For microcirculation research there is a need for baseline data and feasibility protocols describing microcirculation of various organs. The aim of our study was to examine the reliability ...and reproducibility of sidestream dark‐field (SDF) imaging within the renal cortical microcirculation in rats. Renal microcirculation was observed using SDF probe placed on the exposed renal surface via the upper midline laparotomy. Video sequences recorded intermittently in short apneic pauses were analyzed off‐line by using AVA 3.0 software (MicroVision Medical, Amsterdam, the Netherlands). Results are expressed as mean (SD) or median (25–75% percentiles). We obtained 60 clear sequences from all recorded analyzable videos from all the animals. The total small vessel and all vessel density (in mm.mm–2) were (28.79 ± 0.40) and (28.95 ± 0.40), respectively. The perfused small and all vessel density were (28.79 ± 0.40) and (28.95 ± 0.40), respectively. The DeBacker Score was (19.14 ± 0.43), the proportion of perfused vessels was 100% (100–100%) and the microvascular flow index was 3.49 (3–3.75). We conclude SDF imaging provides a reliable method to examine the renal microvascular bed in vivo and thus can be used for the study of the renal cortical vascular network in various experimental diseases models and clinical settings.
Lay Description
This article aims to discuss the practicability of obtaining the baseline data and feasibility protocols needed to describe the microcirculation in various organs.
In order to examine the reproducibility as well as the reliability of obtaining valid microcirculatory data of particular organs, the authors choose a renal cortical microcirculation in rats observed by using the sidestream dark field imaging (SDF). SDF method can be used non‐invasively as well, especially in the sublingual area even in clinical research. However, in this study, the SDF probe is placed on the exposed renal surface. The subsequent analysis of all recorded videos is off‐line using special software capable of image stabilization and semi‐automatic evaluation of microcirculation. The program provides a number of output data, such as vascular density, vascular perfusion and blood velocity.
The findings indicate that SDF imaging provides a reliable method of examining the renal microvascular bed in vivo and thus can be used to study the renal cortical vascular network in various experimental models of diseases and clinical settings.
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