Resultados preliminares en la caracterización geométrica 3D de un litosoma arenoso de progradación deltaica mediante Georadar (GPR) (Fm. Arenisca de Roda, Eoceno, Cuenca de Graus-Tremp).

A set of GPR profiles have been recorded in order to determine the 3D geometry of a prograding delta-front sandbody (Roda sandstone formation, Eocene, Graus-Tremp basin). Common Mid Points (CMP) also have been recorded to obtain the velocity of the electromagnetic wave in ground. In order to build the topsurface of a 3D prism a set of topographic points have been acquired. Most of the GPR profiles are oriented parallel to the progradation direction (NNE-SSW) and show the expected geometries. The 3D prism has been built from the individual profiles, which shows the three dimensional geometry of the sandy lithosome.

An Advocacy for the Use of 3D Stem Cell Culture Systems for the Development of Regenerative Medicine: An Emphasis on Photoreceptor Generation

The availability of stem cells is of great promise to study early developmental stages and to generate adequate cells for cell transfer therapies. Although many researchers using stem cells were successful in dissecting intrinsic and extrinsic mechanisms and in generating specific cell phenotypes, few of the stem cells or the differentiated cells show the capacity to repair a tissue. Advances in cell and stem cell cultivation during the last years made tremendous progress in the generation of bona fide differentiated cells able to integrate into a tissue after transplantation, opening new perspectives for developmental biology studies and for regenerative medicine. In this review, we focus on the main works attempting to create in vitro conditions mimicking the natural environment of CNS structures such as the neural tube and its development in different brain region areas including the optic cup. The use of protocols growing cells in 3D organoids is a key strategy to produce cells resembling endogenous ones. An emphasis on the generation of retina tissue and photoreceptor cells is provided to highlight the promising developments in this field. Other examples are presented and discussed, such as the formation of cortical tissue, the epithelial gut or the kidney organoids. The generation of differentiated tissues and well-defined cell phenotypes from embryonic stem (ES) cells or induced pluripotent cells (iPSCs) opens several new strategies in the field of biology and regenerative medicine. A 3D organ/tissue development in vitro derived from human cells brings a unique tool to study human cell biology and pathophysiology of an organ or a specific cell population. The perspective of tissue repair is discussed as well as the necessity of cell banking to accelerate the progress of this promising field.

Deposition and characterization of lines printed through laser-induced forward transfer

The possibility of printing two-dimensional micropatterns of biomolecule solutions is of great interest in many fields of research in biomedicine, from cell-growth and development studies to the investigation of the mechanisms of communication between cells. Although laser-induced forward transfer (LIFT) has been extensively used to print micrometric droplets of biological solutions, the fabrication of complex patterns depends on the feasibility of the technique to print micron-sized lines of aqueous solutions. In this study we investigate such a possibility through the analysis of the influence of droplet spacing of a water and glycerol solution on the morphology of the features printed by LIFT. We prove that it is indeed possible to print long and uniform continuous lines by controlling the overlap between adjacent droplets. We show how, depending on droplet spacing, several printed morphologies are generated, and we offer, in addition, a simple explanation of the observed behavior based on the jetting dynamics characteristic of the LIFT of liquids.

Diagnostic performance of 3D TSE MRI versus 2D TSE MRI of the knee at 1.5 T, with prompt arthroscopic correlation, in the detection of meniscal and cruciate ligament tears

Abstract Objective: To compare the diagnostic performance of the three-dimensional turbo spin-echo (3D TSE) magnetic resonance imaging (MRI) technique with the performance of the standard two-dimensional turbo spin-echo (2D TSE) protocol at 1.5 T, in the detection of meniscal and ligament tears. Materials and Methods: Thirty-eight patients were imaged twice, first with a standard multiplanar 2D TSE MR technique, and then with a 3D TSE technique, both in the same 1.5 T MRI scanner. The patients underwent knee arthroscopy within the first three days after the MRI. Using arthroscopy as the reference standard, we determined the diagnostic performance and agreement. Results: For detecting anterior cruciate ligament tears, the 3D TSE and routine 2D TSE techniques showed similar values for sensitivity (93% and 93%, respectively) and specificity (80% and 85%, respectively). For detecting medial meniscal tears, the two techniques also had similar sensitivity (85% and 83%, respectively) and specificity (68% and 71%, respectively). In addition, for detecting lateral meniscal tears, the two techniques had similar sensitivity (58% and 54%, respectively) and specificity (82% and 92%, respectively). There was a substantial to almost perfect intraobserver and interobserver agreement when comparing the readings for both techniques. Conclusion: The 3D TSE technique has a diagnostic performance similar to that of the routine 2D TSE protocol for detecting meniscal and anterior cruciate ligament tears at 1.5 T, with the advantage of faster acquisition.

Low-level laser therapy for the prevention of low salivary flow rate after radiotherapy and chemotherapy in patients with head and neck cancer

Abstract Objective: To determine whether low-level laser therapy can prevent salivary hypofunction after radiotherapy and chemotherapy in head and neck cancer patients. Materials and Methods: We evaluated 23 head and neck cancer patients, of whom 13 received laser therapy and 10 received clinical care only. An InGaAlP laser was used intra-orally (at 660 nm and 40 mW) at a mean dose of 10.0 J/cm2 and extra-orally (at 780 nm and 15 mW) at a mean dose of 3.7 J/cm2, three times per week, on alternate days. Stimulated and unstimulated sialometry tests were performed before the first radiotherapy and chemotherapy sessions (N0) and at 30 days after the end of treatment (N30). Results: At N30, the mean salivary flow rates were significantly higher among the laser therapy patients than among the patients who received clinical care only, in the stimulated and unstimulated sialometry tests (p = 0.0131 and p = 0.0143, respectively). Conclusion: Low-level laser therapy, administered concomitantly with radiotherapy and chemotherapy, appears to mitigate treatment-induced salivary hypofunction in patients with head and neck cancer.

Visual SLAM for 3D large-scale seabed acquisition employing underwater vehicles

This paper presents a novel technique to align partial 3D reconstructions of the seabed acquired by a stereo camera mounted on an autonomous underwater vehicle. Vehicle localization and seabed mapping is performed simultaneously by means of an Extended Kalman Filter. Passive landmarks are detected on the images and characterized considering 2D and 3D features. Landmarks are re-observed while the robot is navigating and data association becomes easier but robust. Once the survey is completed, vehicle trajectory is smoothed by a Rauch-Tung-Striebel filter obtaining an even better alignment of the 3D views and yet a large-scale acquisition of the seabed

Java 3D

Tämä insinöörityö kertoo Java 3D -ohjelmointirajapinnan perusteista ja sen käytöstä kolmiulotteisen tietokonegrafiikan luomisessa Java ohjelmointikielellä. Java 3D on rajapinta Java-ohjelmointikielelle, jonka avulla voidaan luoda ja käsitellä kolmiulotteista tietokonegrafiikkaa. Java 3D -rajapinnan avulla käsitellään kolmiulotteista tietokonegrafiikka erityisen maisemagraafimallin avulla. Maisemagraafi on binääripuuta muistuttava malli, joka mahdollistaa kolmiulotteisten kohteiden ja niille tapahtuvien muunnoksien käsittelyn hierarkisessa järjestyksessä. Työssä käydään läpi Java 3D -maisemagraafien luominen ja kolmiulotteisessa avaruudessa sijaitseville kappaleille tehtäviä perusoperaatioita kuten siirtoa ja kiertoa. Lisäksi käydään läpi myös erilaisia animoinnissa ja interaktiossa käytettäviä luokkia, joiden avulla ohjelmoija saa automatisoitua muunnoksia sekä käyttäjä voi antaa syötteitä hiirellä ja näppäimistöllä. Näiden lisäksi käydään läpi myös mallin valaistusta, varjoja, teksturointia sekä omien kolmiulotteisten mallien tuontia Java 3D -maailmaan. Opinnäytetyön yhteydessä on tehty myös kirjo erilaisia esimerkkejä, jotka ovat saatavilla verkkosivustolta osoitteessa http://www.pahvilaatikko.org/j3d lisäksi kopio verkkosivustosta löytyy myös opinnäytetyön mukana tulevalta cd-levyltä.

Computing the persistent homology of range images with alpha shapes

Laser scanning is becoming an increasingly popular method for measuring 3D objects in industrial design. Laser scanners produce a cloud of 3D points. For CAD software to be able to use such data, however, this point cloud needs to be turned into a vector format. A popular way to do this is to triangulate the assumed surface of the point cloud using alpha shapes. Alpha shapes start from the convex hull of the point cloud and gradually refine it towards the true surface of the object. Often it is nontrivial to decide when to stop this refinement. One criterion for this is to do so when the homology of the object stops changing. This is known as the persistent homology of the object. The goal of this thesis is to develop a way to compute the homology of a given point cloud when processed with alpha shapes, and to infer from it when the persistent homology has been achieved. Practically, the computation of such a characteristic of the target might be applied to power line tower span analysis.

Characterisation of pigment particles by scanning electron microscope and image analysis programs

Coating and filler pigments have strong influence to the properties of the paper. Filler content can be even over 30 % and pigment content in coating is about 85-95 weight percent. The physical and chemical properties of the pigments are different and the knowledge of these properties is important for optimising of optical and printing properties of the paper. The size and shape of pigment particles can be measured by different analysers which can be based on sedimentation, laser diffraction, changes in electric field etc. In this master's thesis was researched particle properties especially by scanning electron microscope (SEM) and image analysis programs. Research included nine pigments with different particle size and shape. Pigments were analysed by two image analysis programs (INCA Feature and Poikki), Coulter LS230 (laser diffraction) and SediGraph 5100 (sedimentation). The results were compared to perceive the effect of particle shape to the performance of the analysers. Only image analysis programs gave parameters of the particle shape. One part of research was also the sample preparation for SEM. Individual particles should be separated and distinct in ideal sample. Analysing methods gave different results but results from image analysis programs corresponded even to sedimentation or to laser diffraction depending on the particle shape. Detailed analysis of the particle shape required high magnification in SEM, but measured parameters described very well the shape of the particles. Large particles (ecd~1 µm) could be used also in 3D-modelling which enabled the measurement of the thickness of the particles. Scanning electron microscope and image analysis programs were effective and multifunctional tools for particle analyses. Development and experience will devise the usability of analysing method in routine use.

Fotólise no estado estacionário e com pulso de laser de 1-benzociclanonas e de seus derivados a,a -dimetilados

Laser excitation of 0.01 M solutions of 1-indanone (Ia), 1-tetralone (Ib), 1-benzosuberone (Ic), and their a,a -dimethyl derivatives IIa-c, respectively, in benzene, produced transients with maximum absorption at 425 nm, and lifetimes ranging from 62 ns (IIa) to 5.5ms (Ic). Quenching studies using well known triplet quenchers such as 1,3-cyclohexadiene and oxygen demonstrated the triplet nature of these transients. In the presence of hydrogen donors, such as 2-propanol, the triplet state decay of the ketones Ia-c leads to the formation of the corresponding ketyl radicals, i.e. IIIa-c, which show absorption spectra very similar to the parent ketone, with lmax at 430 nm and lifetime in excess of 20 ms. Steady state irradiations show that the a,a -dimethyl ketones IIa and IIc form ortho-alkyl benzaldehydes probably derived from an initial a-cleavage of the corresponding triplet excited states.

Implementação de um sistema de eletroforese capilar com detecção de fluorescência induzida por laser

A capillary electrophoresis system using laser induced fluorescence detection is described. A Raman system equipped with a microscope has been used to focus the laser beam on the capillary giving a lateral resolution of 1.5 mm. The fluorescence signal of the analyte (ZnPcTS - tetrasulfonated zinc-phthalocyanine) was collected by the microscope objectives and analysed by a monochromator with confocal characteristics equipped with a CCD detector. Electropherograms obtained with this system were compared to those obtained on a commercial instrument, showing that the described system presents a lower detection limit and better resolution.

Kolmiulotteisen konenakojärjestelmän soveltuminen matkapuhelimen alikokoonpanojen testaukseen massatuotannossa

Tässä diplomityössä tutkitaan kolmiulotteisen konenak6järjestelmän soveltuvuutta matkapuhelimien alikokoonpanojen testaukseen massatuotannossa. Tavoitteena oli saada tietoa 3D järjestelmän käytettävyydestä suorituskyvyn ja kapasiteetin suhteen sekä selvittää järjestelmän joustavuutta testattavia tuotteita vaihdettaessa. Haluttiin myös selvittää, että ratkaiseeko 3D järjestelmä käytössä olevan 2D järjestelmän kanssa ilmenneitä ongelmia Järjestelmän suorituskykyä tutkittiin tekemällä testiajoja, joista saatuja tuloksia analysoitiin tilastollisella laadunvalvontaohjelmistolla. Varsinaisen kehitystyön teki konenäköjärjestelmiin erikoistunut alihankkija, jolla on kokemusta 3D testauksesta muilta teollisuuden aloilta. Matkapuhelimien alikokoonpanojen testauksessa laatukriteerit ja tarkkuusvaatimukset ovat kuitenkin liian kovia saavutettaviksi 3D lasertriangulaatioon perustuvaa testausjärjestelmää käytettäessä