908 resultados para Perfect antireflection coatings
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Purpose The purpose of our multidisciplinary study was to define a pragmatic and secure alternative to the creation of a national centralised medical record which could gather together the different parts of the medical record of a patient scattered in the different hospitals where he was hospitalised without any risk of breaching confidentiality. Methods We first analyse the reasons for the failure and the dangers of centralisation (i.e. difficulty to define a European patients' identifier, to reach a common standard for the contents of the medical record, for data protection) and then propose an alternative that uses the existing available data on the basis that setting up a safe though imperfect system could be better than continuing a quest for a mythical perfect information system that we have still not found after a search that has lasted two decades. Results We describe the functioning of Medical Record Search Engines (MRSEs), using pseudonymisation of patients' identity. The MRSE will be able to retrieve and to provide upon an MD's request all the available information concerning a patient who has been hospitalised in different hospitals without ever having access to the patient's identity. The drawback of this system is that the medical practitioner then has to read all of the information and to create his own synthesis and eventually to reject extra data. Conclusions Faced with the difficulties and the risks of setting up a centralised medical record system, a system that gathers all of the available information concerning a patient could be of great interest. This low-cost pragmatic alternative which could be developed quickly should be taken into consideration by health authorities.
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Background: In order to provide a cost-effective tool to analyse pharmacogenetic markers in malaria treatment, DNA microarray technology was compared with sequencing of polymerase chain reaction (PCR) fragments to detect single nucleotide polymorphisms (SNPs) in a larger number of samples. Methods: The microarray was developed to affordably generate SNP data of genes encoding the human cytochrome P450 enzyme family (CYP) and N-acetyltransferase-2 (NAT2) involved in antimalarial drug metabolisms and with known polymorphisms, i.e. CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4, CYP3A5, and NAT2. Results: For some SNPs, i.e. CYP2A6*2, CYP2B6*5, CYP2C8*3, CYP2C9*3/*5, CYP2C19*3, CYP2D6*4 and NAT2*6/*7/*14, agreement between both techniques ranged from substantial to almost perfect (kappa index between 0.61 and 1.00), whilst for other SNPs a large variability from slight to substantial agreement (kappa index between 0.39 and 1.00) was found, e. g. CYP2D6*17 (2850C>T), CYP3A4*1B and CYP3A5*3. Conclusion: The major limit of the microarray technology for this purpose was lack of robustness and with a large number of missing data or with incorrect specificity.
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Tämän työn tavoitteena on suunnitella yksinkertainen Internet-pohjainen mielipidekyselyjärjestelmä sekä esitellä yksityiskohtaisesti järjestelmän toteutus ja siihen liittyvät menetelmät. Menetelmistäesitellään ainoastaan ennalta valitut menetelmät järjestelmän toteutukseen, tietojen esittämiseen, esitystavan muotoiluun sekä tietojen varastointiin. Järjestelmä toteutetaan HTML- ja PHP-kielillä sekä käyttämällä CSS-menetelmän tyylimuotoiluja ja XML-kielen muotoiluun perustuvia tiedostoja tietovarastoina. Järjestelmän suunnitteluun liittyen työssä pyritään kuvaamaan järjestelmään toteutettavat kaksi erillistä käyttöliittymää, pääkäyttäjän käyttöliittymä ja normaalin käyttäjän käyttöliittymä, sekä näihin toteutettavat toiminnot. Pääkäyttäjän tärkeimmät toiminnot ovat mielipidekyselyiden luominen, käyttäjien lisääminen kyselyihin sekä kyselyiden tulosten seuranta. Normaalin käyttäjän toiminnot taas rajoittuvat kirjautumiseen ja kyselyyn vastaamiseen. Järjestelmän toteutuksen kuvauksessa kuvataan tarkasti edellä mainittujen kahden käyttöliittymän toiminnot sekä näiden toimintojen toteutustavat. Lisäksi toteutuksen kuvauksen yhteydessä määritellään tarkasti järjestelmän tietovarastoina toimivien tiedostojen sisällön muoto. Työn lopputuloksena syntyi valituilla toteutustavoilla toteutettu toimiva mielipidekyselyjärjestelmä sekä tämä järjestelmän suunnitteluun ja toteutuksen selvittämiseen keskittynyt dokumentti. Toteutetusta järjestelmästä ei tullut täydellinen vaan jatkokehityksessä voidaan harkita esimerkiksi tietokannan käyttämistä järjestelmän tietovarastoina sekä joidenkin lisäominaisuuksien toteuttamista. Tavoitteeseen päästiin kuitenkin, sillä toteutettu järjestelmä on toimiva ja käyttötarkoitukseensa sopiva.
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Magneto-active polymers are a class of smart materials commonly manufactured by mixing micron-sized iron particles in a rubber-like matrix. When cured in the presence of an externally applied magnetic field, the iron particles arrange themselves into chain-like structures that lend an overall anisotropy to the material. It has been observed through electron micrographs and X-ray tomographs that these chains are not always perfect in structure, and may have dispersion due to the conditions present during manufacturing or some undesirable material properties. We model the response of these materials to coupled magneto-mechanical loading in this paper using a probability based structure tensor that accounts for this imperfect anisotropy. The response of the matrix material is decoupled from the chain phase, though still being connected through kinematic constraints. The latter is based on the definition of a 'chain deformation gradient' and a 'chain magnetic field'. We conclude with numerical examples that demonstrate the effect of chain dispersion on the response of the material to magnetoelastic loading.
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La esparceta es un tradicional cultivo forrajero de gran importancia en determinadas zonas del nordeste español a cuya mejora agronómica y genética se ha prestado poca atención. El presente trabajo analiza la variabilidad existente en los materiales cultivados en nuestro país del tipo común o de un corte y estudia la existencia de diferencias ecotípicas y su caracterización. Los resultados obtenidos ponen de manifiesto la gran variabilidad existente intra e interpoblacional, diferenciándose perfectamente las esparcetas de uno y dos cortes. La diferenciación dentro de cada uno de estos tipos no es tan clara. La zona más homogénea y mejor caracterizada es la de Teruel.
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Given the multiplicity of nanoparticles (NPs), there is a requirement to develop screening strategies to evaluate their toxicity. Within the EU-funded FP7 NanoTEST project, a panel of medically relevant NPs has been used to develop alternative testing strategies of NPs used in medical diagnostics. As conventional toxicity tests cannot necessarily be directly applied to NPs in the same manner as for soluble chemicals and drugs, we determined the extent of interference of NPs with each assay process and components. In this study, we fully characterized the panel of NP suspensions used in this project (poly(lactic-co-glycolic acid)-polyethylene oxide [PLGA-PEO], TiO2, SiO2, and uncoated and oleic-acid coated Fe3O4) and showed that many NP characteristics (composition, size, coatings, and agglomeration) interfere with a range of in vitro cytotoxicity assays (WST-1, MTT, lactate dehydrogenase, neutral red, propidium iodide, (3)H-thymidine incorporation, and cell counting), pro-inflammatory response evaluation (ELISA for GM-CSF, IL-6, and IL-8), and oxidative stress detection (monoBromoBimane, dichlorofluorescein, and NO assays). Interferences were assay specific as well as NP specific. We propose how to integrate and avoid interference with testing systems as a first step of a screening strategy for biomedical NPs.
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Työn tarkoituksena oli tutkia kartonkipohjaisten pakkausmateriaalien läpäisyominaisuuksia sekä pakkausten tiiveyteen vaikuttavia tekijöitä. Työssä verrattiin skaivatun ja skaivaamattoman raakareunan sekä tölkkien pohjaratkaisujen ominaisuuksia vesihöyryn- ja hapen läpäisevyydessä, kun käytetty kartonki oli molemmin puolin polymeeripäällystetty. Tiiveysominaisuuksia tutkittiin myös vuotomittauksin, värjäyksin ja elektronimikroskoopilla. Kuivan elintarvikkeen säilytystestillä ja kilpailijapakkausanalyyseillä oli tarkoituksena myös saada selville eri pakkausmateriaalien ja pakkauksien läpäisevyys- ja tiiveysominaisuuksia. Pakkauksen saumoilla oli yhtä suuri tai suurempi vaikutus vesihöyryn läpäisyssä kuin itse materiaalilla, kun pakkaus oli molemmin puolin polymeeripäällystetty kartonkikuppi. Skaivatun sauman vesihöyrynläpäisy oli vain 4-10 % pienempi kuin raakareunallisen sauman. Pakkauksen ulkopuolisten raakareunojen suojaaminen pienensi vesihöyrynläpäisevyyttä 30 %. Kun pakkauksen sisäpuolen raaka-reuna oli suojattu teipillä, saumoilla ei ollut niin suurta vaikutusta vesihöyryn läpäisyyn verrattuna materiaaliin. Raakareunan määrällä tölkin pohjassa tai pienillä vuodoilla tölkin saumoissa ei ollut merkitystä vesihöyryn läpäisyyn. Hapenläpäisyssä oli tärkeää ehyt barrierkerros. Polymeerisen barrierkerroksen reiät ja sauman skaivaus vaikuttivat enemmän kuin vesihöyryn läpäisyssä. Mitä enemmän tölkin pohjassa oli raakareunaa, sitä suurempi oli sen hapenläpäisy. Pakkauksen konvertointi, koneen säädöt ja lämmön kohdistus, ovat saattaneet aiheuttaa värjäyksellä havaitut barrierkerroksen mikroreiät. Kaupalliset kuiva-ainepakkaukset sisälsivät pääasiassa alumiinilaminaatin vesihöyryn, hapen ja valon suojana, kun tuotteena oli maitojauhetta ja rasvaa sisältävä elintarvike. Kuitenkin, jos pakkausmateriaali sisälsi vain ohuen sumutetun alumiinikerroksen, sen barrieriominaisuus ei ollut yhtä hyvä kuin alumiinilaminaatin. Äidinmaidonkorvikkeen säilytystestissä seurattiin eri analyysein tuotteen laatua kolmen kuukauden säilytyksen ajan. Pakkauksen vesihöyryn läpäisyominaisuus osoittautui tärkeimmäksi, sillä kosteuden vaikutus tuotteen laadun heikkenemisessä oli suurin. Hapen vaikutus on myös olennainen ja siten hyvä hapenestokerros sekä tiiveys ovat myös tärkeitä pakkauksen ominaisuuksia.
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Introduction Occupational therapists could play an important role in facilitating driving cessation for ageing drivers. This, however, requires an easy-to-learn, standardised on-road evaluation method. This study therefore investigates whether use of P-drive' could be reliably taught to occupational therapists via a short half-day training session. Method Using the English 26-item version of P-drive, two occupational therapists evaluated the driving ability of 24 home-dwelling drivers aged 70 years or over on a standardised on-road route. Experienced driving instructors' on-road, subjective evaluations were then compared with P-drive scores. Results Following a short half-day training session, P-drive was shown to have almost perfect between-rater reliability (ICC2,1=0.950, 95% CI 0.889 to 0.978). Reliability was stable across sessions including the training phase even if occupational therapists seemed to become slightly less severe in their ratings with experience. P-drive's score was related to the driving instructors' subjective evaluations of driving skills in a non-linear manner (R-2=0.445, p=0.021). Conclusion P-drive is a reliable instrument that can easily be taught to occupational therapists and implemented as a way of standardising the on-road driving test.
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Chemoprevention is a pragmatic approach to reduce the risk of colorectal cancer, one of the leading causes of cancerrelated death in western countries. In this regard, maslinic acid (MA), a pentacyclic triterpene extracted from wax-like coatings of olives, is known to inhibit proliferation and induce apoptosis in colon cancer cell lines without affecting normal intestinal cells. The present study evaluated the chemopreventive efficacy and associated mechanisms of maslinic acid treatment on spontaneous intestinal tumorigenesis in ApcMin/+ mice. Twenty-two mice were randomized into 2 groups: control group and MA group, fed with a maslinic acid-supplemented diet for six weeks. MA treatment reduced total intestinal polyp formation by 45% (P,0.01). Putative molecular mechanisms associated with suppressing intestinal polyposis in ApcMin/+ mice were investigated by comparing microarray expression profiles of MA-treated and control mice and by analyzing the serum metabolic profile using NMR techniques. The different expression phenotype induced by MA suggested that it exerts its chemopreventive action mainly by inhibiting cell-survival signaling and inflammation. These changes eventually induce G1-phase cell cycle arrest and apoptosis. Moreover, the metabolic changes induced by MA treatment were associated with a protective profile against intestinal tumorigenesis. These results show the efficacy and underlying mechanisms of MA against intestinal tumor development in the ApcMin/+ mice model, suggesting its chemopreventive potential against colorectal cancer.
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Chemoprevention is a pragmatic approach to reduce the risk of colorectal cancer, one of the leading causes of cancerrelated death in western countries. In this regard, maslinic acid (MA), a pentacyclic triterpene extracted from wax-like coatings of olives, is known to inhibit proliferation and induce apoptosis in colon cancer cell lines without affecting normal intestinal cells. The present study evaluated the chemopreventive efficacy and associated mechanisms of maslinic acid treatment on spontaneous intestinal tumorigenesis in ApcMin/+ mice. Twenty-two mice were randomized into 2 groups: control group and MA group, fed with a maslinic acid-supplemented diet for six weeks. MA treatment reduced total intestinal polyp formation by 45% (P,0.01). Putative molecular mechanisms associated with suppressing intestinal polyposis in ApcMin/+ mice were investigated by comparing microarray expression profiles of MA-treated and control mice and by analyzing the serum metabolic profile using NMR techniques. The different expression phenotype induced by MA suggested that it exerts its chemopreventive action mainly by inhibiting cell-survival signaling and inflammation. These changes eventually induce G1-phase cell cycle arrest and apoptosis. Moreover, the metabolic changes induced by MA treatment were associated with a protective profile against intestinal tumorigenesis. These results show the efficacy and underlying mechanisms of MA against intestinal tumor development in the ApcMin/+ mice model, suggesting its chemopreventive potential against colorectal cancer.
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In traffic accidents involving motorcycles, paint traces can be transferred from the rider's helmet or smeared onto its surface. These traces are usually in the form of chips or smears and are frequently collected for comparison purposes. This research investigates the physical and chemical characteristics of the coatings found on motorcycles helmets. An evaluation of the similarities between helmet and automotive coating systems was also performed.Twenty-seven helmet coatings from 15 different brands and 22 models were considered. One sample per helmet was collected and observed using optical microscopy. FTIR spectroscopy was then used and seven replicate measurements per layer were carried out to study the variability of each coating system (intravariability). Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were also performed on the infrared spectra of the clearcoats and basecoats of the data set. The most common systems were composed of two or three layers, consistently involving a clearcoat and basecoat. The coating systems of helmets with composite shells systematically contained a minimum of three layers. FTIR spectroscopy results showed that acrylic urethane and alkyd urethane were the most frequent binders used for clearcoats and basecoats. A high proportion of the coatings were differentiated (more than 95%) based on microscopic examinations. The chemical and physical characteristics of the coatings allowed the differentiation of all but one pair of helmets of the same brand, model and color. Chemometrics (PCA and HCA) corroborated classification based on visual comparisons of the spectra and allowed the study of the whole data set at once (i.e., all spectra of the same layer). Thus, the intravariability of each helmet and its proximity to the others (intervariability) could be more readily assessed. It was also possible to determine the most discriminative chemical variables based on the study of the PCA loadings. Chemometrics could therefore be used as a complementary decision-making tool when many spectra and replicates have to be taken into account. Similarities between automotive and helmet coating systems were highlighted, in particular with regard to automotive coating systems on plastic substrates (microscopy and FTIR). However, the primer layer of helmet coatings was shown to differ from the automotive primer. If the paint trace contains this layer, the risk of misclassification (i.e., helmet versus vehicle) is reduced. Nevertheless, a paint examiner should pay close attention to these similarities when analyzing paint traces, especially regarding smears or paint chips presenting an incomplete layer system.
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We demonstrate the value of high-resolution magnetic resonance imaging (MRI) in diagnosing, staging, and follow-up of retinoblastoma during eye-saving treatment. We have included informative retinoblastoma cases scanned on a 3T MRI system from a retrospective retinoblastoma cohort from 2009 through 2013. We show that high-resolution MRI has the potential to detect small intraocular seeds, hemorrhage, and metastatic risk factors not visible with fundoscopy (e.g., optic nerve invasion and choroidal invasion), and treatment response. Unfortunately, however, the diagnostic accuracy of high-resolution MRI is not perfect, especially for subtle intraocular seeds or minimal postlaminar optic nerve invasion. The most important application of MRI is the detection of metastatic risk factors, as these cannot be found by fundoscopy and ultrasound.
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INTRODUCTION: The aim of this study was to evaluate the concordance of 2- and 3-dimensional radiography and histopathology in the diagnosis of periapical lesions. METHODS: Patients were consecutively enrolled in this study provided that preoperative periapical radiography (PR) and cone-beam computed tomographic imaging of the tooth to be treated with apical surgery were performed. The periapical lesional tissue was histologically analyzed by 2 blinded examiners. The final histologic diagnosis was compared with the radiographic assessments of 4 blinded observers. The initial study material included 62 teeth in the same number of patients. RESULTS: Four lesions had to be excluded during processing, resulting in a final number of 58 evaluated cases (31 women and 27 men, mean age = 55 years). The final histologic diagnosis of the periapical lesions included 55 granulomas (94.8%) and 3 cysts (5.2%). Histologic analysis of the tissue samples from the apical lesions exhibited an almost perfect agreement between the 2 experienced investigators with an overall agreement of 94.83% (kappa = 0.8011). Radiographic assessment overestimated cysts by 28.4% (cone-beam computed tomographic imaging) and 20.7% (periapical radiography), respectively. Comparing the correlation of the radiographic diagnosis of 4 observers with the final histologic diagnosis, 2-dimensional (kappa = 0.104) and 3-dimensional imaging (kappa = 0.111) provided only minimum agreement. CONCLUSIONS: To establish a final diagnosis of an apical radiolucency, the tissue specimen should be evaluated histologically and specified as a granuloma (with/without epithelium) or a cyst. Analysis of 2-dimensional and 3-dimensional radiographic images alike results only in a tentative diagnosis that should be confirmed with biopsy.
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La obtención de recubrimientos con bajos coeficientes de fricción, es una innovadora respuesta a la creciente demanda industrial de alternativas para los tradicionales sistemas lubricados con aceites. Para este fin, la introducción de un sólido lubricante, en una matriz con buenas propiedades mecánicas, ha de conferir al conjunto un bajo coeficiente de fricción y mejorar la resistencia al desgaste del recubrimiento, favoreciendo además, la utilización a elevadas temperaturas, en las que los lubricantes líquidos convencionales presentan limitaciones. En el Centro de Proyección Térmica (CPT) de la Universidad de Barcelona se han obtenido mediante proyección de Plasma Atmosférico (APS) recubrimientos autolubricados de Ni-Grafito y Cr2O3-CaF2, estudiando con especial interés las propiedades y el efecto que produce el grafito y el CaF2 en las matrices metálica y cerámica respectivamente. Se ha determinado en los dos casos que el desgaste originado en los recubrimientos es bajo, si bien los coeficientes de fricción varían ostensiblemente en función del sistema indicado. Los resultados obtenidos indican que el recubrimiento de Ni-Grafito posee un comportamiento idóneo capaz de competir con los tradicionales lubricantes líquidos.
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The improvement of the reliability of the contact between the osseous tissues and the implant materials has been tested by recovering the metallic implants with ceramic materials, usually calcium phosphates. In our study, the calcium phosphate recovering layers were deposited by means of a pulsed-laser deposition technique. Our aim was to to evaluate the tissue interactions established between cortical bone and titanium implants covered by five different layers, ranging from amorphous calcium phosphate to crystalline hydroxyapatite, obtained by altering the parameters of the laser ablation process. The surgical protocol of the study consisted in the simultaneous implantation of the five types of implants in both the tibial dyaphisis of three Beagle dogs, sacrificed respectively one, two and three months after the last surgical procedures. After the sacrifice, the samples were submitted to a scheduled procedure of embedding in plastic polymers without prior decalcification, in order to perform the ultrastructural studies: scanning microscopy with secondary and backscattered electrons (BS-SEM). Our observations show that both in terms of the calcified tissues appearing as a response to the presence of the different coatings and of time of recovering, the implants coated with crystalline calcium phosphate layers by laser ablation present a better result than the amorphous-calcium-phosphate-coated implants. Moreover, the constant presence of chondroid tissue, related with the mechanical induction by forces applied on the recovering area, strongly suggests that the mechanisms implied in osteointegration are related to endomembranous, rather than endochondral ossification processes