Our understanding of phylogenetic relationships among bony fishes has been transformed by analysis of a small number of genes, but uncertainty remains around critical nodes. Genome-scale inferences ...so far have sampled a limited number of taxa and genes. Here we leveraged 144 genomes and 159 transcriptomes to investigate fish evolution with an unparalleled scale of data: >0.5 Mb from 1,105 orthologous exon sequences from 303 species, representing 66 out of 72 ray-finned fish orders. We apply phylogenetic tests designed to trace the effect of whole-genome duplication events on gene trees and find paralogy-free loci using a bioinformatics approach. Genome-wide data support the structure of the fish phylogeny, and hypothesis-testing procedures appropriate for phylogenomic datasets using explicit gene genealogy interrogation settle some long-standing uncertainties, such as the branching order at the base of the teleosts and among early euteleosts, and the sister lineage to the acanthomorph and percomorph radiations. Comprehensive fossil calibrations date the origin of all major fish lineages before the end of the Cretaceous.
This Viewpoint reviews circulating SARS-CoV-2 genetic variants and mechanisms of immunity by which they might escape coronavirus vaccine-induced protection and proposes 6 measures to address them, ...including enhanced variant isolation and testing procedures and continued adherence to mask-wearing and other established public health measures.
Purpose:
To measure real‐time activity values for two manufacturers of Y‐90 microspheres and experimentally determine the differences in activity values resulting from assay and preparation ...techniques; and furthermore to determine the influence microsphere solution homogeneity on these results.
Methods:
A CRC‐15BT dose calibrator was used to record activity values for Y‐90 microspheres every 1000 ms. An I‐125 ADCL calibrated seed was used to benchmark the assay technique. Measurements of Y‐90 microspheres considered preparation with no‐mixing to vigorously shaking for up to 60 seconds testing the effect of solution homogeneity. Activity values based on the microsphere settling time within the vial were contrasted with the activity corrected for decay during the measurement.
Results:
A review of 100+ pre‐administration Y‐90 microsphere delivery vials demonstrated differences between manufacturer supplied activities and in‐house measurements of −3.1% to 2.0% with a standard deviation of 0.9% for vendor‐A and −7.3% to +11.3% with a standard deviation of 3.3% for vendor‐B. For vendor‐A, the real‐time assay of the recorded activity value was found to be independent of the amount of time the vial was shaken prior to measurement. For vendor‐B, the recorded activity showed a dependence on the length of time that the delivery vial was shaken prior to assay resulting in an equilibrium time of approximately 144 seconds for mixing times ≥ 15 seconds. However, this effect is small (∼0.5%) and be considered technician/operator independent.
Conclusion:
Activity values provided by the vendor and those measured at the local clinic can be as large as ±10% and consequently could have significant downstream dosimetric effects. Uncertainties could be reduced if a NIST/ADCL traceable calibration was provided by the vendor. Vendor‐ A provides a certificate while Vendor‐B does not resulting in significantly larger uncertainties. These uncertainties are shown to be independent of the assay technique and entirely vendor dependent.
Durability of electrolyzers is one of the main challenges for their widespread commercialization, although many commercial PEM electrolyzer manufacturers claim durability up to 30,000 h or even ...longer. Nevertheless, their degradation processes are increasingly investigated. There is a need to promptly diagnose degradation causes by monitoring the resulting performance decay. However, a wide spectrum of procedures for degradation testing makes it difficult to compare the obtained results, thus makes their practical application unsuitable. In order to systemize the proposed testing procedures, an overview of investigations that include PEM electrolyzer degradation testing is presented here, together with a comparative analysis and a critical review. The reviewed papers are grouped in accordance to whether the degradation tests were performed under constant or dynamic operating conditions. In addition, the review includes the advances and perspectives in accelerated test development. It was noticed that incomplete or inadequate membrane initial conditioning or activation affects the obtained results and, thus, the extracted conclusions. Therefore, before conducting any relevant degradation test, it is necessary first to define and carry out a suitable activation procedure, in order to compare the results of different degradation tests and reach the correct conclusions, which should be the subject of further research.
•Experimental studies of degradation under constant and dynamic operation reviewed.•Component modification studies and specific processes impact on degradation included.•Lack of standardization of electrolyzer degradation tests and accelerated protocols.•Advances and perspectives in accelerated degradation protocols development presented.•Necessity of using an appropriate activation procedure prior to any degradation test.
Polymerase chain reaction (PCR)‐based nucleic acid testing has played a critical role in disease diagnostics, pathogen surveillance, and many more. However, this method requires a long turnaround ...time, expensive equipment, and trained personnel, limiting its widespread availability and diagnostic capacity. On the other hand, the clustered regularly interspaced short palindromic repeats (CRISPR) technology has recently demonstrated capability for nucleic acid detection with high sensitivity and specificity. CRISPR‐mediated biosensing holds great promise for revolutionizing nucleic acid testing procedures and developing point‐of‐care diagnostics. This review focuses on recent developments in both fundamental CRISPR biochemistry and CRISPR‐based nucleic acid detection techniques. Four ongoing research hotspots in molecular diagnostics‐target preamplification‐free detection, microRNA (miRNA) testing, non‐nucleic‐acid detection, and SARS‐CoV‐2 detection‐are also covered.
This review focuses on recent developments in both fundamental CRISPR biochemistry and CRISPR‐based molecular diagnostic technologies. Four emerging research topics on target preamplification‐free detection, microRNA (miRNA) detection, non‐nucleic‐acid detection, and SARS‐CoV‐2 detection are also covered.
•The concrete age affects the early-age mechanical response.•Referred to the reference mix, varying the quantity of superplasticizer appeared to lower the strengths and the stiffness of the sample, ...increasing the experimental scatter.•The use of an external membrane improved the repeatability of the test, and the failure prediction was more reliable.•The displacement rate affects the stress-strain response at different concrete ages.•The overall effect of the various testing procedures may lead to a failure prediction variability in the range of 30–40%.
Digital fabrication with concrete enables the efficient and quick creation of architectural/structural elements without formworks. This technology does, however, introduce new challenges, especially concerning the mechanical requirements of printable materials. Consequently, the mechanical characterisation of early-age printable mortar is essential for designing, controlling and modelling the printing process, but no standardised testing procedures are currently available. In this paper, the results of uniaxial compressive tests performed on cylindrical samples are compared by varying the testing procedures, with the ultimate goal being to investigate their effect on the time-dependent mechanical properties of printable mortar. Finally, the results are used to predict failure during the printing process due to self-buckling or excessive compression on the first mortar layer. The outcomes highlight the role of specimen preparation, as well as the displacement rate on the predicted critical number of layers.
•Organic paraffins and non-paraffins are suitable PCMs for incorporation into concrete.•Indirect methods of PCM incorporation into concrete avoid PCM leakage.•Microcapsules could help reduce the loss ...in the compressive strength of PCM-concrete.•Testing specifications for measuring thermal properties of PCM-concrete are required.•Thermal conductivity and storage of PCM-concrete increases with high conductive PCM-coatings.
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Phase change materials (PCMs) have been widely used in building applications as a thermal storage medium for passive thermal regulation and for increasing the efficiency of HVAC systems. Both applications have shown great potential in reducing energy demand or peak loads for both heating and cooling in buildings. Literature shows different ways to incorporate PCMs in the building envelope. This review focuses on the use of PCMs as an additive or replacement material in typical concrete mixtures for building applications. Literature shows that organic paraffin and non-paraffins are the most suitable PCMs for incorporation into concrete mixtures, as they have suitable melting points that match human comfort temperature, high heat capacity, low volume changes during phase change transition, and good chemical and thermal stability. To avoid PCM leakage from the concrete, indirect methods of PCM incorporation in concrete are highlighted, such as encapsulation methods and vacuum impregnation techniques combined with macro-encapsulation methods. Updated information related to the influence of the type of PCM and different incorporation methods on the physical, mechanical and thermal properties of fresh and hardened concrete is presented. Literature shows that by adding PCM to the concrete mixture the heat storage capacity of concrete is generally increased. However, various studies showed that PCMs also have some negative impacts on the physical and mechanical properties of concrete. New relationships between the quantity of PCM and the change in both the thermal and mechanical properties of the concrete are provided. From the reviewed literature, it can be concluded that the potential of using PCM in concrete still requires further research, to study solutions that allow increasing the amount of PCM that is effectively incorporated into concrete and to develop standard testing procedures for measuring the thermal properties of inhomogeneous materials such as PCM-concrete composites.
With the ever-increasing demand for development and innovation, organizations must prioritize quality management aspects to ensure the quality of their online products and services. This includes ...implementing effective test management strategies to identify and resolve issues before they impact end users. The aim of this research is to underscore the need for a robust test management plan to ensure stable and trustworthy web services. As such, it proposes best practice solutions for organizations in the field of quality control and testing, which have a high impact on improving knowledge management. This study used an observational approach to assess the importance of quality assurance in IT projects and its impact on knowledge management. The findings presented in this paper highlight the critical role that quality control and testing procedures play in promoting effective knowledge management. Furthermore the outcomes of the study show that in order to deliver world-class software and services, organizations must prioritize effective test management and continuous quality assurance.