Bibliographies: '-µ analyse in situ' – Grafiati (2024)

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✓ In previous studies of topical application of calphostin C, a specific inhibitor of the regulatory domain of protein kinase C (PKC), and calpeptin, a selective inhibitor of calpain, to spastic canine basilar artery (BA) researchers have suggested that the catalytic fragment of PKC (known as PKM) is probably formed by a limited proteolysis of continuously activated µ-calpain, but there has been no direct evidence for PKM formation in vasospasm. The present immunoblot study with anti-PKCα antibody shows a significant decrease in cytosolic 80-kD PKCα and a concomitantly significant increase in membrane PKCα in the spastic canine BA. In addition, an immunoblot study in which cleavage site—directed antibodies were used demonstrated a significant increase in immunoreactive 45-kD PKM. The changes in membrane PKCα and PKM were enhanced with the lapse of time after subarachnoid hemorrhage. The cleavage site—directed antibodies distinguish the proteolyzed from the unproteolyzed forms of PKC for in situ analyses of enzyme regulation mediated by proteolysis. The data indicate that PKCα in spastic canine BA is translocated to the cell membrane, where PKCα is rapidly cleaved into PKM as a result of proteolysis of the isozyme by µ-calpain but not by µ-calpain. The authors hypothesize that µ-calpain is continuously activated in spastic canine BA and produces PKM by limited proteolysis of PKCα.

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In transportation light metal matrix composites (L-MMCs) are used increasingly due to their improved creep resistance even at higher application temperatures. Therefore, the creep behavior and failure mechanisms of creep loaded particle reinforced L-MMCs have been investigated intensively. Until now, creep damage analyses are usually performed ex situ by means of interrupted creep experiments. However, ex situ methods do not provide sufficient information about the evolution of creep damage. Hence, in situ synchrotron X-ray 3D-µ-tomography investigations were carried out enabling time and space resolved studies of the damage mechanisms in particle-reinforced titanium- and aluminum-based metal matrix composites (MMCs) during creep. The 3D-data were visualized and existing models were applied, specifying the phenomenology of the damage in the early and late creep stages. During the early stages of creep, the damage is determined by surface diffusion in the matrix or reinforcement fracture, both evolving proportionally to the macroscopic creep curve. In the late creep stages the damage mechanisms are quite different: In the Al-MMC, the identified mechanisms persist proportional to creep strain. In contrast, in the titanium-MMC, a changeover to the mechanism of dislocation creep evolving super-proportionally to creep strain occurs.

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Abstract The existence of open dumping in Medan City’s final waste processing since 1993 has certainly had a negative impact in the form of a decrease in air quality which has a further impact on public health problems. This study aims to analyse and maps the distribution of PM10 and PM2.5 concentrations in the Terjun Landfill and to examine the relationship between the air quality index and the prevalence of acute respiratory infection (ARI) in the nearby landfill site. The sampling method for this research uses the manual active and is mapped using the GIS application. The results of ambient air concentrations were converted into an air quality index which subsequently was tested in a statistical correlative method to investigate the prevalence of ARI. The results demonstrated the PM2.5 concentrations ranged from 38.94 – 163.1 µ/m3, the PM10 was between 46.84 – 184.2 µ/m3; indicating an excessive level of national ambient threshold. The distribution of the highest PM2.5 and PM10 is in the active zone of the landfill. The prevalence of ARI in the nearby landfill site showed a strong relationship; 0.86 for PM2.5 and 0.62 for PM10. These findings illustrate a poor-quality air would increase the number of inhabitants with ARI.

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This paper reports the diagnostic research of deteriorated paint layers from three mural panels made by Almada Negreiros found in the Alcântara Maritime Station in Lisbon. The aim was to understand the main decay phenomena to aid future conservation works. The methodology comprised in-situ analyses by technical photography in Vis, Vis-RaK and UVF, p-OM and h-EDXRF; micro sampling; OM, SEM-EDS, μ-XRD, μ-Raman, µ-FT-IR and Py-GC/MS. Preliminary results show that all the paint layers analyzed are affected by salts (alkali sulphates) that over time have caused flacking, lack of cohesion, erosion, and lacunae. The light greenish/greenish bluish paint layers in all three panels are the most affected. No organic binders were identified, only the presence of vinyl polymer in glossy paint surfaces.

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Additive manufacturing has been considered a suitable process for developing high-performance parts of medical or aerospace industries. The electron beam powder bed fusion process, EB-PBF, is a powder bed fusion process carried out in a vacuum, in which the parts are melted using a highly focused electron beam. The material class of metastable β-titanium alloys, and especially Ti-5Al-5Mo-5V-3Cr, show great potential for use as small and highly complex load-bearing parts. Specimens were additively manufactured with optimised process parameters and different heat treatments used in order to create tailored mechanical properties. These heat-treated specimens were analysed with regard to their microstructure (SEM) and their mechanical strength (tensile testing). Furthermore, in situ tensile tests, using a Deben CT5000 and a YXLON ff35 industrial µ-CT, were performed and failure-critical defects were detected, analysed and monitored. Experimental results indicate that, if EB-PBF-manufactured Ti-5553 is heat-treated differently, a variety of mechanical properties are possible. Regarding their fracture mechanisms, failure-critical defects can be detected at different stages of the tensile test and defect growth behaviour can be analysed.

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An interactive computer program GLAMPILE has been developed for predicting the static load capacity of single piles formed in any soil profile. A variety of well-known prediction methods have been incorporated into the program, including (i) soil mechanics based formulae; (ii) direct and indirect cone penetration test (CPT) based methods with and without accounting for scale effects of the cone on pile base capacity; and (iii) a new CPT-based method that considers the effects of “critical depth” and shaft resistance distribution, although the method has only been calibrated for relatively short piles. GLAMPILE can cope with different pile types installed with or without a permanent casing. The program has been applied to predict the axial capacities of 11 piles that were recently installed in sand and statically loaded to failure. Results from the soil mechanics procedures indicate increases, on the in situ value, of the earth pressure coefficient by up to 37%, which lies within the range 0%–100% recommended in the literature. The best CPT-based prediction method applied yields a mean (µ) and coefficient of variation (COV) of predicted to measured pile head capacity (Puh(p)/Puh(m)) of 0.83 and 0.12, respectively. Scale effects are shown to be nominal for the cases analysed. An improved method is recommended, which yields µ = 1.00 and COV = 0.10, implying higher accuracy and reliability compared with the other methods.Key words: piles, cone penetration test, static and dynamic load test, modular program.

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This study involves the preparation of conducting composites based on poly(o-methoxyaniline) (POMA) and carbon nanotubes (CNT) and the evaluation of them as radar absorbing materials (RAM), in the frequency range of 8.2–12.4 GHz (X-band). The composites were obtained by synthesis in situ of POMA in the presence of CNT (0.1 and 0.5 wt% in relation to the o-methoxyaniline monomer). The resulting samples—POMA/CNT-0.1 wt% and POMA/CNT-0.5 wt%—were incorporated in an epoxy resin matrix in the proportion of 1 and 10 wt%. FT-IR analyses show that the POMA was successfully synthesized on the CNT surface. SEM analyses show that the synthesized POMA recovered all CNT surface. Electrical conductivity measurements show that the CNT contributed to increase the conductivity of POMA/CNT composites (1.5–6.7 S·cm−1) in relation to the neat POMA (5.4 × 10−1 S·cm−1). The electromagnetic characterization involved the measurements of complex parameters of electrical permittivity (ε) and magnetic permeability (µ), using a waveguide in the X-band. From these experimental data reflection loss (RL) simulations were performed for specimens with different thicknesses. The complex parameters show that the CNT in the composites increased ε and µ. These results are attributed to the CNT network formation into the composites. Simulated RL curves of neat POMA and POMA/CNT in epoxy resin show the preponderant influence of POMA on all RL curves. This behavior is attributed to the efficient CNT recovering by POMA. RL results show that the composite based on 10 wt% of POMA/CNT-0.5 wt% in epoxy resin (9 mm thickness) presents the best RL results (≈87% of attenuation at 12.4 GHz).

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Two novel iminophenolate ligands with amidopropyl side chains (HL2 and HL3) on the imine functionality have been synthesized in order to prepare dioxidomolybdenum(VI) complexes of the general structure [MoO2L2] featuring pendant internal hydrogen bond donors. For reasons of comparison, a previously published complex featuring n-butyl side chains (L1) was included in the investigation. Three complexes (1–3) obtained using these ligands (HL1–HL3) were able to activate dioxygen in an in situ approach: The intermediate molybdenum(IV) species [MoO(PMe3)L2] is first generated by treatment with an excess of PMe3. Subsequent reaction with dioxygen leads to oxido peroxido complexes of the structure [MoO(O2)L2]. For the complex employing the ligand with the n-butyl side chain, the isolation of the oxidomolybdenum(IV) phosphino complex [MoO(PMe3)(L1)2] (4) was successful, whereas the respective Mo(IV) species employing the ligands with the amidopropyl side chains were found to be not stable enough to be isolated. The three oxido peroxido complexes of the structure [MoO(O2)L2] (9–11) were systematically compared to assess the influence of internal hydrogen bonds on the geometry as well as the catalytic activity in aerobic oxidation. All complexes were characterized by spectroscopic means. Furthermore, molecular structures were determined by single-crystal X-ray diffraction analyses of HL3, 1–3, 9–11 together with three polynuclear products {[MoO(L2)2]2(µ-O)} (7), {[MoO(L2)]4(µ-O)6} (8) and [C9H13N2O]4[Mo8O26]·6OPMe3 (12) which were obtained during the synthesis of reduced complexes of the type [MoO(PMe3)L2] (4–6).

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This paper presents the absorbance and fluorescence optical properties of various phytoplankton species, looking to achieve an accurate method to detect and identify a number of phytoplankton taxonomic groups. The methodology to select the excitation and detection wavelengths that results in superior identification of phytoplankton is reported. The macroscopic analyses and the implemented methodology are the base for designing a lab-on-a-chip device for a phytoplankton group identification, based on cell analysis with multi-wavelength lighting excitation, aiming for a cheap and portable platform. With such methodology in a lab-on-a-chip device, the analysis of the phytoplankton cells’ optical properties, e.g., fluorescence, diffraction, absorption and reflection, will be possible. This device will offer, in the future, a platform for continuous, autonomous and in situ underwater measurements, in opposition to the conventional methodology. A proof-of-concept device with LED light excitation at 450 nm and a detection photodiode at 680 nm was fabricated. This device was able to quantify the concentration of the phytoplankton chlorophyll a. A lock-in amplifier electronic circuit was developed and integrated in a portable and low-cost sensor, featuring continuous, autonomous and in situ underwater measurements. This device has a detection limit of 0.01 µ/L of chlorophyll a, in a range up to 300 µg/L, with a linear voltage output with chlorophyll concentration.

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Woodlice efficiently sequester copper (Cu) in ‘cuprosomes' within hepatopancreatic ‘S' cells. Binuclear ‘B’ cells in the hepatopancreas form iron (Fe) deposits; these cells apparently undergo an apocrine secretory diurnal cycle linked to nocturnal feeding. Synchrotron-based µ-focus X-ray spectroscopy undertaken on thin sections was used to characterize the ligands binding Cu and Fe in S and B cells of Oniscus asellus (Isopoda). Main findings were: (i) morphometry confirmed a diurnal B-cell apocrine cycle; (ii) X-ray fluorescence (XRF) mapping indicated that Cu was co-distributed with sulfur (mainly in S cells), and Fe was co-distributed with phosphate (mainly in B cells); (iii) XRF mapping revealed an intimate morphological relationship between the basal regions of adjacent S and B cells; (iv) molecular modelling and Fourier transform analyses indicated that Cu in the reduced Cu + state is mainly coordinated to thiol-rich ligands (Cu–S bond length 2.3 Å) in both cell types, while Fe in the oxidized Fe 3+ state is predominantly oxygen coordinated (estimated Fe–O bond length of approx. 2 Å), with an outer shell of Fe scatterers at approximately 3.05 Å; and (v) no significant differences occur in Cu or Fe speciation at key nodes in the apocrine cycle. Findings imply that S and B cells form integrated unit-pairs; a functional role for secretions from these cellular units in the digestion of recalcitrant dietary components is hypothesized.

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Le comportement des halogènes (F, Cl, Br et I) dans les systèmes magmatiques est loin d'être clairement compris. La communauté scientifique n'a qu'une connaissance fragmentaire des processus qui influencent le comportement de ces éléments pendant le stockage et l'ascension des magmas. Les études récentes du comportement des halogènes lourds comme le brome et l'iode se sont principalement concentrées sur les magmas liés à la subduction, dans le contexte du cycle géochimique des halogènes depuis la subduction jusqu'à l'atmosphère. Les études antérieures sur la solubilité des halogènes (à saturation en saumure) ont montré que les liquides calco-alcalins felsiques, fortement polymérisés, présentent une solubilité des halogènes (à l'exception du F) plus faible que les liquides felsiques riches en alcalins. En outre, les magmas riches en alcalins peuvent produire des éruptions de grand volume (par exemple, le système du rift est-africain), ce qui peut conduire à une émission massive d'halogènes dans l'atmosphère. Les émissions d'halogènes dans l'atmosphère sont donc potentiellement sous-estimées dans ces contextes, en raison d'un manque de compréhension détaillée du comportement des halogènes (et notamment du brome et de l'iode) pendant le dégazage magmatique. Dans ce contexte, l'objectif de cette thèse est de contraindre expérimentalement le partage des halogènes entre la phase fluide magmatique et le liquide silicaté dans les systèmes alcalins felsiques et de conduire une étude préliminaire de l'abondance des halogènes (notamment du brome et de l'iode) dans les verres alcalins naturels mafiques à felsiques provenant de différents contextes géodynamiques. Nous avons réalisé des expériences HP-HT (800 -1100 °C ; 10-200 MPa ; NNO-0.6 - NNO+3.4) en utilisant quatre compositions de liquide silicaté de teneur en SiO2 et de rapport molaire [(Na₂O+K₂O)/Al₂O₃] variables (phonolite, comendite, pantellerite et un analogue synthétique de la composition phonolitique). Nos résultats montrent que la composition du liquide a un impact important sur le partage des halogènes entre le fluide et le liquide silicaté. Le Dhalogens (avec Dhalogens = concentration de l'halogène dans la phase fluide/concentration de l'halogène dans le liquide silicaté) augmente avec la teneur en SiO₂ et diminue avec l'alcalinité des liquides, en accord avec les données de solubilité. Nous avons effectué une étude systématique de l'influence de la température et de la pression sur le partage des halogènes entre le fluide et le liquide silicaté et les résultats montrent que la température a un effet plus prononcé sur le partage que la pression. L'influence des conditions redox a également été étudiée et les résultats montrent que le D_I diminue avec la diminution de la fO2, tandis que DBr et le DCl montrent un effet inverse. Nous présentons la première détermination des abondances en halogènes lourds (Br et I) dans des verres felsiques riches en alcalins, avec des concentrations de l'ordre de ~10 ppm de Br et jusqu'à ~1 ppm de I dans les rhyolites riches en alcalins. Les concentrations en iode de ces verres sont au moins un ordre de grandeur plus élevées que les concentrations déterminées par l'analyse roche totale des produits volcaniques calco-alcalins publiées par ailleurs, mettant en exergue la nécessité de quantifier davantage les halogènes lourds dans les magmas afin de mieux évaluer les émissions atmosphériques d'halogènes et leur impact sur l'environnement
The behavior of halogens (F, Cl, Br and I) in magmatic systems is far from being clearly understood. The scientific community has only a fragmentary understanding of the processes that influence the behaviour of these elements during magma storage and ascent to the surface. Recent studies of heavy halogens (Br and I) behaviour have focused mainly on subduction-related magmas, in the context of the geochemical cycle of the halogens from subduction to the atmosphere. Previous studies of halogens solubility (at brine saturation) have shown that felsic, highly-polymerized calc-alkaline melts have lower halogens (except F) solubility than felsic alkali-rich melts. In addition, alkali-rich melts can produce large volume eruptions (e.g., East Africa Rift System), leading to potential massive release of halogens into the atmosphere. Emissions of halogens to the atmosphere are therefore likely to be underestimated, due to the lack of detailed understanding of the behavior of halogens (and in particular bromine and iodine) during magmatic degassing. In this work, we have addressed this gap by experimentally constraining fluid/melt halogen partitioning in felsic alkali-rich systems, with a focus on Br and I, and by a preliminary study of halogens abundances in natural mafic to felsic alkali-rich glasses from different geodynamic contexts. We performed HP-HT experiments (800°-1100 °C; 10 -200 MPa; NNO-0.6 -NNO+3.4) using four melt compositions, with variable SiO2 contents and [(Na₂O+K₂O)/Al₂O₃] molar ratios (natural phonolite, comendite and pantellerite and a synthetic analogue of phonolitic composition). Our results show that melt composition has a strong effect on the partitioning of halogens between fluid and melt. Dhalogens (with Dhalogens = halogen concentration in the fluid phase / halogen concentration in the silicate melt) increases with SiO₂ content and decreases with melt alkalinity, in agreement with the solubility data. We have carried out a systematic investigation of the influence of temperature and pressure on the fluid-melt partitioning of halogens and the results show that temperature has a more pronounced effect on partitioning than pressure. The effect of the redox conditions on halogens fluid/melt partitioning was also explored and the results indicate that DI decreases with decreasing fO₂, whereas DBr and DCl show the opposite effect. We present the first determination of heavy halogens (Br and I) abundances in felsic alkali-rich glasses, with concentrations in the order of ~10 ppm of Br and up to ~1 ppm of I in alkali-rich rhyolites. Iodine concentrations for these melts are at least an order of magnitude higher than concentrations determined by bulk rock analysis of calc-alkaline volcanic rocks in previous studies, highlighting the need for further quantification of heavy halogens in magmas to better assess their atmospheric emission and impact

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Dans un monde en constante évolution technologique, les capteurs micro électromécaniques (MEMS) prennent une place prépondérante dans divers domaines tels que la biomédecine, l’industrie aérospatiale et les technologies de l’information et de la communication. Au cœur de cette révolution, les micro-poutres cantilever offrent une sensibilité exceptionnelle, permettant la détection de variations physiques infimes. Cette thèse se consacre à la conception d’une nouvelle architecture de capteurmicro-poutres cantilever, visant à optimiser leur sensibilité et à étendre leurs applications pratiques. Le travail entrepris s’est focalisé sur l’élaboration d’un modèle théorique et la validation expérimentale d’une structure cantilever plongée dans un fluide newtonien incompressible, caractérisée par des dimensions précises et une conception innovante. La partie numérique de l’étude a permis de tester la sensibilité de l’architecture proposée face à des charges externes, tandis que les expériences pratiques ont impliqué la fabrication et l’assemblage minutieux des composants du capteur, y compris l’intégration de matériaux piézoélectriques. L’innovation ne s’arrête pas là ; l’avenir envisagel’incorporation de revêtements biochimiques pour la détection spécifique et l’utilisation de techniques microfluidiques pour une analyse en temps réel, marquant ainsi un pas en avant significatif dans la recherche et le développement des MEMS. La quête de sensibilité accrue dans les capteurs MEMS cantilever nous a menés à la conception et à l’élaboration d’une structure optimisée, explorée à travers ce travail de thèse. L’intégration réussie de l’architecture exponentielle dans la micro-poutre cantilever et l’application de techniques de pointe en fabrication et en tests numériques représentent des avancées significatives dans la recherche en MEMS. Les résultats obtenus ouvrent des perspectives fascinantes pour l’amélioration et l’application de ces capteurs dans des environnements complexes. Les futurs travaux, incluant l’application de revêtements biochimiques et le développement de chambres microfluidiques, promettent d’étendre encore davantage le champ d’application et d’efficacité de ces dispositifs sensibles.En résumé, cette thèse contribue à l’avancement de la science et de la technologie des capteurs MEMS, en proposant des solutions innovantes pour les défis actuels et futurs dans les domaines nécessitant une détection précise et une sensibilité accrue. Elle pose ainsi les bases pour les développements futurs qui bénéficieront sans aucun doute à de nombreuses disciplines scientifiques et applications industrielles
In a world of continuous technological evolution, micro-electromechanical system (MEMS) sensors are becoming increasingly prominent in various fields such as biomedicine, the aerospace industry,and information and communication technologies. At the heart of this revolution, cantilever microbeams provide exceptional sensitivity, allowing the detection of minute physical variations. This thesis is dedicated to the design of a new cantilever microbeam sensor architecture aimed at optimizing their sensitivity and expanding their practical applications. The work undertaken focused on developing a theoretical model and experimental validation of a cantilever structure immersed in an incompressible Newtonian fluid, characterized by precise dimensions and an innovative design. The numerical part of the study allowed for testing the sensitivity of the proposed architecture against external loads, while the practical experiments involved the meticulous fabrication and assembly of the sensor components, including the integration of piezoelectric materials. Innovation does not stop here; the future envisions the incorporation of biochemical coatings for specific detection and the use of microfluidic techniques for real-time analysis, thereby marking a significant step forward in MEMS research and development. The quest for increased sensitivity in cantilever MEMS sensors has led us to the design and creation of an optimized structure, explored through this thesis work. The successful integration of the exponential architecture into the cantilever microbeam and the application of cutting-edge techniques in fabrication and numerical testing represent significant advancements in MEMS research. The results obtained open exciting prospects for the improvement and application of these sensors in complex environments. Future work, including the applicationof biochemical coatings and the development of microfluidic chambers, promises to further extend the scope of application and effectiveness of these sensitive devices. In summary, this thesis contributes to the advancement of science and technology in MEMS sensors, proposing innovative solutions for current and future challenges in fields requiring precise detection and increased sensitivity. It thus lays the groundwork for future developments that will undoubtedly benefit many scientific disciplines and industrial applications

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La diffusion raman, ex-situ et in-situ, methode d'analyse structurale et chimique, a ete utilisee pour comprendre le vieillissem*nt thermochimique et l'etat des contraintes des fibres ceramiques dans une matrice ceramique. Dans un premier temps, la demarche a consiste a selectionner une matrice ceramique (suffisamment transparente) et des interphases sol-gel fonctionnelles, observables en microscopie raman. Le diagramme zro#2-geo#2 des phases apparaissant par traitement thermique des gels a ete determine. La specificite des interphases sol-gel a faible module d'elasticite (microporeuses et/ou microfissurees) conduisant a une rupture dissipative du composite, a ete analysee par microdurete pour des systemes tout-oxyde. La validite du modele de decomposition spectrale et les attributions qui en decoulent sont discutes. La degradation des fibres sic nlm 202#t#m est correlee a une reaction d'oxydation interne et a l'apparition d'un desordre unidirectionnel a l'echelle meme de l'empilement des tetraedres sic, tandis que la destabilisation des fibres hi-nicalon#t#m, pauvres en oxygene, est concomitante a une reorganisation du continuum si#1#-#xc#1#+#x a l'echelle moleculaire. Afin d'evaluer l'etat de deformation des fibres in-situ, un etalonnage des deplacements du nombre d'onde en fonction de l'allongement impose ex-situ ( = f(deformation)) par extensometrie raman sur fibres traitees a 1000c a ete fait, apres avoir valide le protocole experimental (effet des puissances d'excitation, de la procedure de decomposition). On montre l'importance de disposer de donnees statistiques afin de correler les proprietes locales des fibres aux proprietes mecaniques macroscopiques du composite

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Par le theme aborde la thermique du batiment l'auteur apporte une contribution du point de vue de la modelisation des transferts thermiques qui s'operent au sein d'une cellule calorimetrique. Il utilise en effet des techniques de representation des circuits rc, issus du domaine de l'electronique, et, grace a des analogies classiques, trouve dans le domaine de la thermique des systemes lineaires un champ d'application. Le memoire comporte deux grandes parties: 1) la premiere est consacree a la part importante du travail concernant l'etude experimentale. Apres une presentation detaillee de l'outil experimental et de son instrumentation l'auteur aborde la methodologie adaptee ainsi que les resultats obtenus sur des baies vitrees a simple et double vitrage; 2) la deuxieme a trait a l'etablissem*nt d'un logiciel de simulation qui complete l'etude experimentale. L'auteur aborde la modelisation bidimensionnelle avec flux solaire incident. Il introduit pour le traitement des phenomenes de rayonnement avec multi reflexions une representation par cellule en t. Les parois opaques sont representees par des quadripoles. A partir de ces quadripoles, l'auteur utilise le concept de fonction de transfert et uvre vers la formulation de la reponse d'une paroi a l'aide de produits de convolution. L'utilisation du calcul iteratif et de la methode de convolution recursive limite les capacites memoires et permet l'implantation de son logiciel de calcul sur micro-ordinateur. Les performances et la souplesse d'utilisation du logiciel sont mises en evidence par la comparaison entre prediction et mesures

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AbstractA large part of marine pollution studies is about collecting, analysing, and interpreting the concentrations of contaminants in the environment. This involves field and laboratory work to collect and analyse the samples. Some analyses are completed directly in the field (i.e., in situ). From the process of collection through to the final analyses, there are many quality assurance and quality control (QA/QC) steps that are required, which, when used properly, ensure sample integrity and the reliability of results, therefore, resulting in meaningful interpretations and conclusions.

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AbstractThe archaeological excavation carried out in 2018 by W. Van Andringa, T. Creissen and H. Duday at Porta Nocera, Pompeii, brought to light a new funerary enclosure. During the excavation, a hom*ogeneous layer was unearthed right below the eruptive deposit layers of 79 AD. This stratum revealed several traces of occupation linked to the funerary enclosure. As the fine excavation of the artifacts proceeded, the position and form of every single fragment unearthed was methodically recorded in situ as a supplement to the multidisciplinary studies realised by specialists. This exceptional context of preservation enabled us to implement an innovative 3D spatial analysis of the objects and their fragmentation, in order to understand the nature and frequency of commemorative gestures at the human space-time scale. The use of digital 3D visualisation thus permits us to analyse and demonstrate the existence of certain ephemeral human acts that would otherwise not be perceived. Here, I present the method and first results, which will be integrated into a thesis directed by Prof. W. Van Andringa.

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Abstract The rapid accumulation of large amounts of information from in situ hybridization experiments, together with the spatial and temporal complexity of this kind of data, presents serious difficulties for conventional publishing methods and for the individual researcher who wants to collate and analyse other people's results in relation to his own studies. The solution to these problems is to construct a database of gene expression and several are now being built; most apply to embryos, but in the future it is likely that they will be extended to include the adult.

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In this paper authors presented the development and validation of RP-HPLC method for determination of related substances present in Montelukast sodium and Levocetirizine dihydrochloride combined tablets. Chromatographic separation was achieved on Hypersil ODS (150 x 4.6 mm),5 µ column with flow rate 1 mL/min, detection wavelength 238 nm, injection volume 10 µL, column temperature 40°C and run time 75 mins. Gradient programming was used with mobile phase-A (MP-A)-50mM acetate buffer pH 5.5 and mobile phase-B(MP-B)-methanol: MP-A (90:10 %v/v). Developed method was validated as per ICH Q2(R1) guideline. As the method was able to analyse forced degradation samples successfully, it proved to be stability-indicating.

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Abstract Image analysis provides a wide range of sophisticated measurement techniques. Even so, it is often difficult to analyse histological and cytological preparations automatically since, in many cases, standard detection methods simply do not interpret the image well enough on their own to find the regions to be measured. This is particularly true for radiolabelled in situ hybridization. The issue of recognition is complex, since the best approach to interpreting an image automatically often depends on background information about the sample and about the aims of the experiment. Important changes in the approach adopted by manufacturers of image analysis equipment are promising advances. The first is a shift away from developing general analysis software and towards developing analysis software that will solve particular problems in interpreting types of images.

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The estimation of microplastic pollution in the terrestrial and aquatic ecosystem is carried out by quantification and identification of the contaminated environment. Microplastic estimation consists of various steps such as sampling, visualization and quantification. Generally, the planktonic net, bongo net, manta net, and neuston net have been used for water sampling. While, grab samplers, tweezers, tablespoons, trowels, shovels, spatulas, or hand picking methods have been used for soil and sediment sampling. The biological sample from the study sites comprises the direct collection of the whole organism or its colony as a sampling unit. However all samples are required to be processed further to extract the microplastic using techniques such as filtration, density extraction, digestion, and magnetic & electrostatic extraction. The digestion method is used for direct characterization such as thermal gravimetric analysis. The identification of microplastic is based on microscopic images which provide the shape, size, colour, and texture of the microplastic surface. Visual identification using microscopes is time-consuming and susceptible to human error as well as a risk of misidentification, which leads to underestimation or overestimation of microplastic pollution. Spectroscopic methods such as ATR-FTIR, µ-FTIR and Raman spectroscopy provide identification and quantification of synthetic polymer. Advance combined analytical techniques have been reported during the last few years such as portable micro-Raman, SEM-FTIR, Pyr-GC-MS, TGA-DSC, and PEE. Priority and care are essential concerning the sampling, storage and handling microplastic samples for the QA/QC for accurate analysis. The present chapter aims to provide a comprehensive overview of the current knowledge of tools and techniques used for microplastic inquiries from an environmental sample.

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Indirect additive manufacturing techniques like Material Extrusion (MEX) are rising in industrial application due to the freedom of design usually attributed to additive processing, as well as accessibility and a real contribution to sustainability. This study highlights the role of µ-tomography as a core of non-destructive techniques to optimize shaping and sintering parameters. Moreover, brings forth the possibility of continuous improvement and quality control without disposable specimens. Therefore, this study aims to optimize the manufacture of metallic specimens (AISI 316L), for similar feedstock (binder/additive), by using µ-tomography to analyse the filament, the strand, and the 3Dobject (green and sintered). Optimization the different MEX steps relies on setting key process variables and understanding their impact on defects using µ-tomography. This methodology allows the evaluation of 3Dobjects quality by non-destructive techniques.

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APA, Harvard, Vancouver, ISO, and other styles

APA, Harvard, Vancouver, ISO, and other styles

APA, Harvard, Vancouver, ISO, and other styles

Abstract:

Le Groupe µ et "le système de formes plastiques” -à propos d’une évaluation- L’objectif de cet article est de fournir quelques exemples et de proposer certains éclaircissem*nts qui peuvent contribuer à la compréhension de la théorie du signe plastique conçu par le Groupe μ. Plus précisément, l’article porte sur les éléments de la théorie en question qui constituent une analyse du système de la forme tant qu’elle est distincte du système de la couleur et du système de la texture. Dans l’espoir de faire connaître quelques-uns des fondations et des implications de ce système de forme plastique, principalement aux lecteurs anglo-saxons, l’article tente également de clarifier sa place au sein de la théorie générale du signe visuel articulé par Groupe μ dans son Traité du signe visuel (1992). La première section de l’article traite de la notion esthétique générale de forme et de sa relation avec d'une part la notion de forme/formation visuelle et de l'autre la notion de forme sémiotique telle qu’elle a été développée par Hjelsmlev. On prend note du risque que les visées d’une sémiotique plastique puissent être indûment confondues avec celles du formalisme dans l'esthétique. Selon l’avis de l’auteur, les études de sémiotique visuelle ne sauraient bénéficier de ce genre de confusion, mais devraient plutôt tenter de maintenir sa distance par rapport aux conjectures et luttes de pouvoir dans le(s) monde(s) de l'art. La deuxième section explique la distinction faite par le Groupe μ entre le signe iconique et le signe plastique, conçus comme des couches séparées du signe visuel. Selon le Groupe μ, le signe iconique forme une structure triadique contenant le signifiant, le type et le référent. Il y a des similarités entre cette conception et le triangle d’Ogden & Richards. Or, la notion du Type a des implications plus vastes que la conception d’Ogden & Richards, selon lesquels il existe une image très générale qui met en relation symbole/signifier et référent – le type est ici le résultat de modélisations et de catégorisations, et il est valable aussi bien pour le signe iconique que pour le signe plastique. Par définition, le signe plastique manque de référent : la relation entre un motif et ses variations dépend donc uniquement du rapport Signifier/Type. Sur la base de cette relation Signifier/Type, les signes plastiques apparaissent, selon le Groupe µ, aux trois niveaux de la sémiose, sur le niveau purement plastique, sur le niveau extravisuel (ou symbolique), et dans une interaction avec le signe iconique sur le niveau iconico-plastique. La troisième section de l’article explique le système de forme plastique telle qu’elle est conçue par le Groupe μ. Le système est constitué par trois « formemes » (ou catégories), à savoir position, dimension et l'orientation. Il est conçu en termes de figures apparaissant dans un plan restreint. Comme les relations fondamentales dans le plan sont celles entre le centre - la marge, le haut - le bas et la gauche - la droite, le système de positions alternatives (par exemple marginal, au-dessus et au centre) est isomorphe au système d'autres orientations (par exemple vers l'intérieur, d'en haut vers le centre). Le système d'autres dimensions/tailles, par contraste, est défini par le biais de la fonction de la taille de la figure en relation à la taille du plan de l’image et le point focal. Ces valeurs plastiques de position, de dimension et d’orientation sont les signifiants du système. Ils sont liés à leurs signifiés de la manière suivante : la position à l’attraction, la dimension à la domination, l'orientation à l'équilibre. Cette corrélation est validée par les auteurs au moyen d’une démonstration visuelle. Dans la quatrième et dernière section de l’article, des observations sont faites au sujet des répercussions plus vastes ainsi que des applications du système. Conformément à la visée du propre Groupe µ à surmonter les limitations qui résultent de la spécialisation de disciplines telles que la psychologie de la perception, l'auteur soutient que des systèmes théoriques comme celui du système plastique peut fournir un cadre interdisciplinaire qui facilite l’évaluation à la fois des données scientifiques et des discours philosophiques généraux concernant le monde visuel. En ce qui concerne des applications plus proches, l'auteur estime que les théories du sens visuel et de la rhétorique du Groupe μ, si elles étaient plus largement connues, contribueraient considérablement à la compréhension de l'importance du sens plastique dans la communication visuelle et au développement des méthodes pédagogiques pour la description et l’interprétation de l'image.

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Considering existing microscopical techniques to study microstructures of materials, one can find that non-destructive information from the internal structure of an object in natural conditions can be obtained by transmission X-ray microscopy. Combination of X-ray transmission technique with tomographical reconstruction allows to get three-dimensional information about the internal microstructure. In this case any internal area can be reconstructed as a set of flat cross sections which can be used to analyse the two- and three-dimensional morphological parameters. For X-ray methods the contrast in the images is a mixed combination of density and compositional information which provides means for non-destructive reconstruction of the internal structure. The paper presents experimental results of crack propagation and fibre bridging glass fibre epoxy samples that were collected in-situ during loading in a X-ray scanner.

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APA, Harvard, Vancouver, ISO, and other styles

APA, Harvard, Vancouver, ISO, and other styles

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Road design is a complex, time-consuming, and very responsible process. To develop a high-quality and viable road project, it is very important to start with an accurate geological investigation. In situ tests can provide a number of advantages over the traditional drilling, sampling and laboratory testing approach used in many geotechnical projects. However, like all tests, in situ tests also have a number of limitations. Although all probing methods are similar, each of them gives slightly different results. The aim of this work was to analyse and compare the interpretation results of soil layer physical-mechanical properties obtained with different in-situ test methods and to find out how the obtained results affect the development of constructive solutions from the safety point of view.

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Cadmium is a toxic metal causing environmental concern in connection with utilization and land filling of ash. Knowledge about the chemical associations of Cd in ash is fundamental in the understanding of its solubility and leachability from the ash. In the work presented here, the content, distribution and chemical forms of Cd on/in individual Municipal Solid Waste (MSW) and biomass fly ash particles have been investigated in situ by Synchrotron Radiation induced μ-X-ray fluorescence, absorption spectrometry (XAS) and fluorescence tomography. These X-ray micro-beam techniques can be used to reveal spatially resolved information about structural and chemical properties of particles. The use of an excitation energy of 27 keV made it possible to detect trace metals, such as Cd at ppm levels, but also other elements, like Ca, K, Cl and Br. Absorption spectra of Cd in the energy range around the absorption edge of Cd (26.71 keV) were recorded for micron-sized spots of ash particles. Fluorescence tomography was then use to establish if Cd compounds are situated on the particle surface (i.e. most prone to leaching) or at some depth within the particle, where they might be more shielded from chemical attack by water. The measurements indicated Cd to be preferably concentrated in some small areas (“hot-spots”) with high concentration (up to 200 ppm) in MSW fly ash particles and in a hom*ogeneous distribution over the whole particle surface in the case of biomass. Comparisons of XAS spectra of fly ashes and reference compounds showed Cd to be present in the oxidation state +2 and mainly as CdSO4, CdO and CdCl2. Although previous studies have indicated Cd to be enriched in the smaller-size ash particles, in this study Cd was found to be reasonably well distributed throughout all the particle sizes investigated. Based on the results obtained, possible reaction mechanisms involving Cd are suggested.

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The accuracy of the Copernicus Marine Environment and Monitoring Service (CMEMS) ocean analysis and forecasts highly depend on the availability and quality of observations to be assimilated. In situ observations are complementary to satellite observations that are restricted to the ocean surface. Higher resolution model forecasts are required by users of the CMEMS global and regional ocean analysis and forecasts. To support this with an efficient observational constrain of the model forecast via data assimilation, an increase observation coverage is needed, associated with an improved usage of the available ocean observations. This work exploits the capabilities of operational systems to provide comprehensive information for the evolution of the GOOS. In this report, we analyse the use and the efficiency of the in-situ observations to constrain regional and global Mercator Ocean systems. Physical and biogeochemical variables are considered. The in-situ observations are used either to estimate physical ocean state at global and regional scale via data assimilation or to estimate BGC model parameters. The impact of the physical in situ observations assimilated in open ocean and coastal areas is assessed with numerical data assimilation experiments. The experiments are conducted with the regional 1/36° resolution and global 1/12° resolution systems operated by Mercator Ocean for the Copernicus Marine Service. For the global physical ocean, the focus is on the tropical ocean to better understand how the tropical mooring observations constrain the intraseasonal to daily variability and the complementarity with satellite observations and the deep ocean. The tropical moorings provide unique high frequency observations at different depth, but they are far away from each other, so part of the signal in the observation are decorrelated from one mooring to the others. It is only via an integrated approach, as data assimilation into a dynamical model and complementarity with other observing networks that those observations can efficiently constrain the different scales of variability of the tropical ocean circulation. As the satellite observations brings higher spatial resolution between the tropical moorings but for the ocean surface, we show that the tropical mooring and Argo profile data assimilation constrain the larger scale ocean thermohaline vertical structure (EuroSea D2.2; Gasparin et al., 2023). The representation of the high frequency signals observed at mooring location is also significantly improved in the model analysis compared to a non-assimilative simulation. The ocean below 2000 m depth is still largely under constrained as very few observations exist. Some deep ocean basins, as the Antarctic deep ocean, shows significant trend over the past decade but they are still not accurately monitored. Based on the spread of four deep ocean reanalysis estimates, large uncertainties were estimated in representing local heat and freshwater content in the deep ocean. Additionally, temperature and salinity field comparison with deep Argo observations demonstrates that reanalysis errors in the deep ocean are of the same size as or even stronger than the observed deep ocean signal. OSSE already suggested that the deployment of a global deep Argo array will significantly constrain the deep ocean in reanalysis to be closer to the observations (Gasparin et al., 2020). At regional and coastal scales, the physical ocean circulation is dominated by higher frequency, smaller scale processes than the open ocean which requires different observation strategy to be well monitor. The impact of assimilating high frequency and high-resolution observations provided by gliders on European shelves is analysed with the regional Iberic Biscay and Irish (IBI) system. It was found that repetitive glider sections can efficiently help to constrain the transport of water masses flowing across those sections. BGC ocean models are less mature than physical ocean models and some variable dependencies are still based on empirical functions. In this task, Argo BGC profile observations were used to optimize the parameters of the global CMEMS biogeochemical model, PISCES. A particle filter algorithm was chosen to optimize a 1D configuration of PISCES in the North Atlantic. The optimization of the PISCES 1D model significantly improves the model's ability to reproduce the North Atlantic bloom Recommendations on the in-situ network extensions for real time ocean monitoring are given based on those results, and the one also obtained in the WP2, Task 2.2 where data assimilation experiments but with simulated observations where conducted. Argo extension and the complementarity with satellite altimetry was also extensively studied. (EuroSea Deliverable ; D4.8)