5,639 research outputs found
Method Description and Demonstration
This work was mainly funded by ERC‐CoG‐2014, ChapTherPV, 647596 and partially by H2020‐ICT‐2014‐1, RIA, TransFlexTeg, 645241, FEDER funds through the COMPETE 2020 Program and National Funds through FCT – Portuguese Foundation for Science and Technology with the reference SFRH/BD/135948/2018.
Publisher Copyright:
© 2020 The Authors. Published by Wiley-VCH GmbH.The reproducibility of chemical synthesis is of crucial importance for both chemical industry and research. The development of simple yet robust methods and algorithms that generate a set of data to help the community access their method's reproducibility is desirable. We report a method for obtaining, processing and analyzing recorded images, using scripting language Python 3, from any camera that allows continuous visualization and recording of a chemical synthesis. The method can be used to assert synthesis reproducibility, to capture reaction events that might elude the naked eye and later be isolated in posterior reactions, to refine synthesis parameters such as temperature, microwave power and time and also to understand chemical reactions during synthesis. The method was exemplified with two microwave-assisted synthesis, zinc sulfide and silver sulfide, processed at our lab and applied to videos from other authors.publishersversionpublishe
ARCHI: pipeline for light curve extraction of CHEOPS background star
High precision time series photometry from space is being used for a number
of scientific cases. In this context, the recently launched CHEOPS (ESA)
mission promises to bring 20 ppm precision over an exposure time of 6 hours,
when targeting nearby bright stars, having in mind the detailed
characterization of exoplanetary systems through transit measurements. However,
the official CHEOPS (ESA) mission pipeline only provides photometry for the
main target (the central star in the field). In order to explore the potential
of CHEOPS photometry for all stars in the field, in this paper we present
archi, an additional open-source pipeline module{\dag}to analyse the background
stars present in the image. As archi uses the official Data Reduction Pipeline
data as input, it is not meant to be used as independent tool to process raw
CHEOPS data but, instead, to be used as an add-on to the official pipeline. We
test archi using CHEOPS simulated images, and show that photometry of
background stars in CHEOPS images is only slightly degraded (by a factor of 2
to 3) with respect to the main target. This opens a potential for the use of
CHEOPS to produce photometric time series of several close-by targets at once,
as well as to use different stars in the image to calibrate systematic errors.
We also show one clear scientific application where the study of the companion
light curve can be important for the understanding of the contamination on the
main target.Comment: 14 pages, 13 figures, accepted for publication in MNRAS, all code
available at https://github.com/Kamuish/arch
HBIM application in historic timber structures: A systematic review
Despite the recent significant increase on the use of Building Information Modelling (BIM) in the cultural heritage field, its application on heritage timber structures aiming at their conservation and assessment has not yet been fully established. Comparing with other construction materials, timber presents singular features that must be addressed in order to carry out a proper condition assessment. For this reason, this review summarizes existing works on historical timber structures using Historical BIM (HBIM), focusing not only on various geometric surveying and 3D modelling methods, but also on nongeometric information included in the model which are especially related with conservation, testing, and monitoring. In addition, this work illustrates the effectiveness increase given by a structural analysis, as to assess structural heath, after being implemented within a HBIM-based framework. To that aim, a global framework is proposed where the development and implementation level of different analysis stages are described.This work has been supported by Xunta de Galicia through grant GRC-ED431C 2020/01. This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/04029/2020. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 769255. The sole responsibility for the content of this publication lies with the authors. It does not necessarily reflect the opinion of the European Union. Neither the Innovation and Networks Executive Agency (INEA) nor the European Commission are responsible for any use that may be made of the information contained therein
Topological field theories in n-dimensional spacetimes and Cartan's equations
Action principles of the BF type for diffeomorphism invariant topological
field theories living in n-dimensional spacetime manifolds are presented. Their
construction is inspired by Cuesta and Montesinos' recent paper where Cartan's
first and second structure equations together with first and second Bianchi
identities are treated as the equations of motion for a field theory. In
opposition to that paper, the current approach involves also auxiliary fields
and holds for arbitrary n-dimensional spacetimes. Dirac's canonical analysis
for the actions is detailedly carried out in the generic case and it is shown
that these action principles define topological field theories, as mentioned.
The current formalism is a generic framework to construct geometric theories
with local degrees of freedom by introducing additional constraints on the
various fields involved that destroy the topological character of the original
theory. The latter idea is implemented in two-dimensional spacetimes where
gravity coupled to matter fields is constructed out, which has indeed local
excitations.Comment: LaTeX file, no figure
αvβ3 and α5β1 integrin-specific ligands: From tumor angiogenesis inhibitors to vascularization promoters in regenerative medicine?
Integrins are cell adhesion receptors predominantly important during normal and tumor angiogenesis. A sequence present on several extracellular matrix proteins composed of Arg-Gly-Asp (RGD) has attracted attention due to its role in cell adhesion mediated by integrins. The development of ligands that can bind to integrins involved in tumor angiogenesis and brake disease progression has resulted in new investigational drug entities reaching the clinical trial phase in humans. The use of integrin-specific ligands can be useful for the vascularization of regenerative medicine constructs, which remains a major limitation for translation into clinical practice. In order to enhance vascularization, immobilization of integrin-specific RGD peptidomimetics within constructs is a recommended approach, due to their high specificity and selectivity towards certain desired integrins. This review endeavours to address the potential of peptidomimetic-coated biomaterials as vascular network promoters for regenerative medicine purposes. Clinical studies involving molecules tracking active integrins in cancer angiogenesis and reasons for their failure are also addressed.Prémios Santa Casa Neurociências - Prize Melo e Castro for Spinal Cord Injury Research; Portuguese Foundation for Science and Technology [Doctoral fellowship (PD/BDE/127835/2016) to L. A. Rocha; IF Development Grant to A. J. Salgado; national funds through grant TUBITAK/0007/2014]. This article has been developed under the scope of the projects NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER); This work has been funded by FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the project POCI-01-0145-FEDER-007038info:eu-repo/semantics/publishedVersio
Saharan air intrusions as a relevant mechanism for Iberian heatwaves: the record breaking events of August 2018 and June 2019
The summers of 2018 and 2019 were characterized by unusually warm conditions over Europe. Here, we describe the intense heatwaves striking the Iberian Peninsula in early August 2018 and late June 2019. The 2018 episode was relatively short-lived but outstanding in amplitude, particularly in western Iberia. Similar to previous mega-heatwaves, the 2019 event was long-lasting and affected large areas of western and central Europe, including eastern Iberia. During these events, many absolute temperature records were broken in western and eastern Iberia, respectively (some of them standing since 2003). In both cases, a cyclonic circulation off the coast in the northeastern Atlantic and a strong subtropical ridge pattern over the affected area promoted the advection of an anomalously warm air mass. This paper highlights the role of these very warm, stable and dry air intrusions of Saharan origin in the western and eastern Iberia heatwave events. Using a thermodynamical classification based on the geopotential height thickness and potential temperature, we show how the magnitude and poleward extension of these Saharan intrusions were unprecedented in the period since 1948. The relationship between Iberian heatwaves and Saharan warm air intrusions is discussed in the long-term context, showing a closer link in southern sectors of the Peninsula. However, a consistent poleward trend in the latitudinal extension of these subtropical intrusions reveals their increasing relevance for heatwaves in northern sectors of Iberia and western Europe. This overall trend is accompanied by an apparent “see-saw” in the occurrence of subtropical intrusions between eastern and western Iberia on multi-decadal scales
Efficient and versatile manipulation of the peripheral CD4+ T-cell compartment by antigen targeting to DNGR-1/CLEC9A
DC NK lectin group receptor-1 (DNGR-1, also known as CLEC9A) is a C-type lectin receptor expressed by mouse CD8α+ DC and by their putative equivalents in human. DNGR-1 senses necrosis and regulates CD8+ T-cell cross-priming to dead-cell-associated antigens. In addition, DNGR-1 is a target for selective in vivo delivery of antigens to DC and the induction of CD8+ T-cell and Ab responses. In this study, we evaluated whether DNGR-1 targeting can be additionally used to manipulate antigen-specific CD4+ T lymphocytes. Injection of small amounts of antigen-coupled anti-DNGR-1 mAb into mice promoted MHC class II antigen presentation selectively by CD8α+ DC. In the steady state, this was sufficient to induce proliferation of antigen-specific naïve CD4+ T cells and to drive their differentiation into Foxp3+ regulatory lymphocytes. Co-administration of adjuvants prevented this induction of tolerance and promoted immunity. Notably, distinct adjuvants allowed qualitative modulation of CD4+ T-cell behavior: poly I:C induced a strong IL-12-independent Th1 response, whereas curdlan led to the priming of Th17 cells. Thus, antigen targeting to DNGR-1 is a versatile approach for inducing functionally distinct CD4+ T-cell responses. Given the restricted pattern of expression of DNGR-1 across species, this strategy could prove useful for developing immunotherapy protocols in humans
The Lavic Lake Fault: A Long-Term Cumulative Slip Analysis via Combined Field Work and Thermal Infrared Hyperspectral Airborne Remote Sensing
The 1999 Hector Mine earthquake ruptured to the surface in eastern California, with >5 m peak right-lateral slip on the Lavic Lake fault. The cumulative offset and geologic slip rate of this fault are not well defined, which inhibits tectonic reconstructions and risk assessment of the Eastern California Shear Zone (ECSZ). With thermal infrared hyperspectral airborne imagery, field data, and auxiliary information from legacy geologic maps, we created lithologic maps of the area using supervised and unsupervised classifications of the remote sensing imagery. We optimized a data processing sequence for supervised classifications, resulting in lithologic maps over a test area with an overall accuracy of 71 ± 1% with respect to ground-truth geologic mapping. Using all of the data and maps, we identified offset bedrock features that yield piercing points along the main Lavic Lake fault and indicate a 1036 +27/−26 m net slip, with 1008 +14/−17 m horizontal and 241 +51/−47 m vertical components. For the contribution from distributed shear, modern off-fault deformation values from another study imply a larger horizontal slip component of 1276 +18/−22 m. Within the constraints, we estimate a geologic slip rate of <4 mm/yr, which does not increase the sum geologic Mojave ECSZ rate to current geodetic values. Our result supports previous suggestions that transient tectonic activity in this area may be responsible for the discrepancy between long-term geologic and present-day geodetic rates
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