138 research outputs found
Detection of indigenous organic matter in rocks from the interpretation of carbon molecular forms in the laser-induced plasma.
Oil shale, a sedimentary rock containing organic matter and a variety of inorganic minerals including carbonates and
kerogens, serves as a significant source of organic material on Earth [1]. Kerogen, the most abundant form of organic
matter, differs in chemical composition based on the microorganisms that contributed to its formation [2]. Laser-induced
breakdown spectroscopy (LIBS) is a powerful analytical technique used on the Mars rover, allowing elemental
characterization of Martian rocks, soils, and sediments.
This study presents the first-ever detection of natural organic matter in oil shale using LIBS under simulated Martian
conditions. Through an analysis of emitting species including CN and C2, LIBS successfully identifies the presence of
organic compounds in this sedimentary rock. The ability to detect and characterize natural organic matter in oil shale,
known for its potential to suggest the existence of ancient life, holds significant relevance in astrobiology. Furthermore,
this information contributes to the identification of biosignatures and aids in the development of planetary exploration
strategies.
Oil shale samples were analyzed using LIBS under simulated Martian conditions after being crushed, pressed into
pellets, and subjected to pyrolysis to remove organic matter. The analysis revealed significant changes in the infrared
spectra, confirming the absence of aliphatic hydrocarbons after pyrolysis [3]. The LIBS results demonstrated the
presence of molecular species associated with hydrocarbons, such as CN and C2, through distinct spectral emissions.
The absence of these emissions in the pyrolyzed sample further supported the detection of organic matter originating
from kerogen.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Detection of kerogens in sedimentary rocks by LIBS. Implications for the search for biosignatures on Mars.
Congreso Internacional dedicado a la aplicaciones de LIBSOil shale is a sedimentary rock that naturally contains organic matter. In its chemical composition presents a wide range of inorganic minerals including carbonates, silicates, etc. and kerogens – a mixture of fossil hydrocarbons. Kerogen is insoluble in normal organic solvents, being the most abundant source of organic matter on Earth [1,2]. Chemical composition of a particular kerogen differs as a function of the source microrganisms that participated to the sediment and may be classified into three categories [3]. Type I kerogen, produced by algae or eventually bacteria and is the less abundant; type II, derived from other aquatic organisms (phytoplankton and zooplankton); the most common on Earth is type III, generated from organic plant matter.
To the best of our knowledge, this work demonstrates for the first time the detection of natural organic matter in different rock of oil shales with a total organic carbon content between (2.78 % and 15.06 %) using LIBS under Martian conditions. A linear correlation was found between the net CN intensity and the concentration of total organic material of the samples under CO2 and Martian atmosphere.
The fact that natural organic matter can be detected and characterized by LIBS in this kind of sedimentary rock – known for suggesting the existence ancient life - through its emitting species such as CN or C2 is of great relevance in astrobiology. Results presented here, may provide essential understanding on the search for biosignatures on Mars and for the development of planetary exploration strategies.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
Catálogo de lencería e vestiario
Catálogo onde se relacionan todos os artigos de lencería e vestiario utilizados polo Servizo Galego de Saúde, no que se describe de forma individual as características básicas dos artigos (cor, composición, gramaxe,...) e a serigrafíaCatálogo donde se relacionan todos los artículos de lencería y vestuario utilizados por el Servizo Galego de Saúde, en el que se describe de forma individual las características básicas de los artículos (color, composición, gramaje,...) y la serigrafí
Parallel evolutionary biclustering of short-term electric energy consumption
Presentación realizada en el marco del Proyecto PINV18-661: Análisis de la eficiencia energética en edificios no residenciales mediante técnicas metaheurísticas y de inteligencia artificial.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI
Redundancy Is Not Necessarily Detrimental in Classification Problems
In feature selection, redundancy is one of the major concerns since the removal of redun dancy in data is connected with dimensionality reduction. Despite the evidence of such a connection, few works present theoretical studies regarding redundancy. In this work, we analyze the effect of redundant features on the performance of classification models. We can summarize the contribution of this work as follows: (i) develop a theoretical framework to analyze feature construction and selection, (ii) show that certain properly defined features are redundant but make the data linearly separable, and (iii) propose a formal criterion to validate feature construction methods. The results of experiments suggest that a large number of redundant features can reduce the classification error. The results imply that it is not enough to analyze features solely using criteria that measure the amount of information provided by such features.CONACYT - Consejo Nacional de Ciencia y TecnologíaPROCIENCI
Comparative study of the primary cilia in thyrocytes of adult mammals
Since their discovery in different human tissues by Zimmermann in 1898, primary cilia have been found in the vast majority of cell types in vertebrates. Primary cilia are considered to be cellular antennae that occupy an ideal cellular location for the interpretation of information both from the environment and from other cells. To date, in mammalian thyroid gland, primary cilia have been found in the thyrocytes of humans and dogs (fetuses and adults) and in rat embryos. The present study investigated whether the existence of this organelle in follicular cells is a general event in the postnatal thyroid gland of different mammals, using both immunolabeling by immunofluorescence and electron microscopy. Furthermore, we aimed to analyse the presence of primary cilia in various thyroid cell lines. According to our results, primary cilia are present in the adult thyroid gland of most mammal species we studied (human, pig, guinea pig and rabbit), usually as a single copy per follicular cell. Strikingly, they were not found in rat or mouse thyroid tissues. Similarly, cilia were also observed in all human thyroid cell lines tested, both normal and neoplastic follicular cells, but not in cultured thyrocytes of rat origin. We hypothesize that primary cilia could be involved in the regulation of normal thyroid function through specific signaling pathways. Nevertheless, further studies are needed to shed light on the permanence of these organelles in the thyroid gland of most species during postnatal life.Junta de Andalucía. Consejería de Innovación, Ciencia y Empresa CTS-439/2011Junta de Andalucía. Consejería de Innovación, Ciencia y Empresa CTS-229/2011Junta de Andalucía. Consejería de Salud PI-0051-201
CartoCell, a high-content pipeline for 3D image analysis, unveils cell morphology patterns in epithelia
Decades of research have not yet fully explained the mechanisms of epithelial self-organization and 3D packing. Single-cell analysis of large 3D epithelial libraries is crucial for understanding the assembly and function of whole tissues. Combining 3D epithelial imaging with advanced deep-learning segmentation methods is essential for enabling this high-content analysis. We introduce CartoCell, a deep-learning-based pipeline that uses small datasets to generate accurate labels for hundreds of whole 3D epithelial cysts. Our method detects the realistic morphology of epithelial cells and their contacts in the 3D structure of the tissue. CartoCell enables the quantification of geometric and packing features at the cellular level. Our single-cell cartography approach then maps the distribution of these features on 2D plots and 3D surface maps, revealing cell morphology patterns in epithelial cysts. Additionally, we show that CartoCell can be adapted to other types of epithelial tissues.This work is supported by the project PID2019-103900GB-I00 funded by
MCIN/AEI /10.13039/501100011033 and Programa Operativo FEDER Andalucía 2014–2020 (US-1380953) to L.M.E. Work by L.M.E. and J.A.A.-S.R. has
been funded by the Junta de Andalucía (Consejerı´a de economı´a, conocimiento, empresas y Universidad) grant PY18-631 co-funded by FEDER funds.
A.T. has been funded by a ‘‘Contrato predoctoral PIF’’ from Universidad de
Sevilla. C.G.-V. has been funded by a ‘‘Contrato predoctoral para la formacio´ n
de doctores’’ BES-2017-082306. G.B. was supported by a Comunidad de Madrid contract (CAM) and by an FPI grant from MINECO (BES-2022-077789).
F.M.-B. was supported by MICINN (PID2020-120367GB-I00) and Fundacio´ n
Ramo´ n Areces (CIVP18A3904). P.G.-G. has been funded by Margarita Salas
Fellowship – NextGenerationEU. C.H.F.-E. has been funded by Marı´a Zambrano Fellowship – NextGenerationEU. I.A.-C. would like to acknowledge
that his work has been partially supported by the University of the Basque
Country UPV/EHU grant GIU19/027 and by grant PID2021-126701OB-I00,
funded by MCIN/AEI/10.13039/501100011033 and by ‘‘ERDF A way of making
Europe." L.M.E. also wants to thank PIE-202120E047 – Conexiones-Life
network for networking and input
CartoCell, a high-content pipeline for 3D image analysis, unveils cell morphology patterns in epithelia
Decades of research have not yet fully explained the mechanisms of epithelial self-organization and 3D packing. Single-cell analysis of large 3D epithelial libraries is crucial for understanding the assembly and function of whole tissues. Combining 3D epithelial imaging with advanced deep-learning segmentation methods is essential for enabling this high-content analysis. We introduce CartoCell, a deep-learning-based pipeline that uses small datasets to generate accurate labels for hundreds of whole 3D epithelial cysts. Our method detects the realistic morphology of epithelial cells and their contacts in the 3D structure of the tissue. CartoCell enables the quantification of geometric and packing features at the cellular level. Our single-cell cartography approach then maps the distribution of these features on 2D plots and 3D surface maps, revealing cell morphology patterns in epithelial cysts. Additionally, we show that CartoCell can be adapted to other types of epithelial tissues
Colloidal Solutions with Silicon Nanocrystals: Structural and Optical Properties
In this work, colloidal solutions with silicon nanoparticles using different solvents were synthetized. Structural, morphological and optical characterizations were realized, and these were studied. X-ray diffraction (XRD) was used to measure the diffractograms of the colloidal solutions, which are composed of silicon nanocrystals (Si-ncs), with an average size of approximately 3 nm, and a preferential crystalline orientation (311). Atomic force microscopy (AFM) images show that the morphology of silicon nanoparticles (Si-nps) is agglomerated in a big amount, which is corroborated by means of the roughness. On the other hand, high resolution transmission electronic microscopy (HRTEM) images show on average size of the Si-nc ranging from 1.5 to 10 nm, which depends on the solvent used. Also, different preferential crystalline orientations of the Si-nc such as (311), (220) and (111) were obtained. A correlation between the optical and structural properties was realized in colloidal solutions with silicon nanoparticles and different solvents
Amphiphilic Acrylic Nanoparticles Containing the Poloxamer Star Bayfit® 10WF15 as Ophthalmic Drug Carriers
Topical application of drops containing ocular drugs is the preferred non-invasive route to treat diseases that a_ect the anterior segment of the eye. However, the formulation of eye drops is a major challenge for pharmacists since the access of drugs to ocular tissues is restricted by several barriers. Acetazolamide (ACZ) is a carbonic anhydrase inhibitor used orally for the treatment of ocular hypertension in glaucoma. However, large ACZ doses are needed which results in systemic side e_ects. Recently, we synthesized copolymers based on 2-hydroxyethyl methacrylate (HEMA) and a functionalized three-arm poloxamer star (Bayfit-MA). The new material (HEMA/Bayfit-MA) was engineered to be transformed into nanoparticles without the use of surfactants, which represents a significant step forward in developing new ophthalmic drug delivery platforms. Acetazolamide-loaded nanocarriers (ACZ-NPs) were prepared via dialysis (224 +/- 19 nm, ̶ 17.2 +/- 0.4 mV). The in vitro release rate of ACZ was constant over 24 h (cumulative delivery of ACZ: 83.3 +/- 8.4%). Following standard specifications, ACZ-NPs were not cytotoxic in vitro in cornea, conjunctiva, and macrophages. In normotensive rabbits, ACZ-NPs generated a significant intraocular pressure reduction compared to a conventional solution of ACZ (16.4% versus 9.6%) with the same dose of the hypotensive drug (20 μg). In comparison to previously reported studies, this formulation reduced intraocular pressure with a lower dose of ACZ. In summary, HEMA:Bayfit-MA nanoparticles may be a promising system for ocular topical treatments, showing an enhanced ocular bioavailability of ACZ after a single instillation on the ocular surface
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