901 resultados para bispectral features
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Spectroscopic ellipsometry and high resolution transmission electron microscopy have been used to characterize microcrystalline silicon films. We obtain an excellent agreement between the multilayer model used in the analysis of the optical data and the microscopy measurements. Moreover, thanks to the high resolution achieved in the microscopy measurements and to the improved optical models, two new features of the layer-by-layer deposition of microcrystalline silicon have been detected: i) the microcrystalline films present large crystals extending from the a-Si:H substrate to the film surface, despite the sequential process in the layer-by-layer deposition; and ii) a porous layer exists between the amorphous silicon substrate and the microcrystalline silicon film.
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Background: Information about the composition of regulatory regions is of great value for designing experiments to functionally characterize gene expression. The multiplicity of available applications to predict transcription factor binding sites in a particular locus contrasts with the substantial computational expertise that is demanded to manipulate them, which may constitute a potential barrier for the experimental community. Results: CBS (Conserved regulatory Binding Sites, http://compfly.bio.ub.es/CBS) is a public platform of evolutionarily conserved binding sites and enhancers predicted in multiple Drosophila genomes that is furnished with published chromatin signatures associated to transcriptionally active regions and other experimental sources of information. The rapid access to this novel body of knowledge through a user-friendly web interface enables non-expert users to identify the binding sequences available for any particular gene, transcription factor, or genome region. Conclusions: The CBS platform is a powerful resource that provides tools for data mining individual sequences and groups of co-expressed genes with epigenomics information to conduct regulatory screenings in Drosophila.
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The decision to settle a motor insurance claim by either negotiation or trial is analysed. This decision may depend on how risk and confrontation adverse or pessimistic the claimant is. The extent to which these behavioural features of the claimant might influence the final compensation amount are examined. An empirical analysis, fitting a switching regression model to a Spanish database, is conducted in order to analyze whether the choice of the conflict resolution procedure is endogenous to the compensation outcomes. The results show that compensations awarded by courts are always higher, although 95% of cases are settled by negotiation. We show that this is because claimants are adverse to risk and confrontation, and are pessimistic about their chances at trial. By contrast, insurers are risk - confrontation neutral and more objective in relation to the expected trial compensation. During the negotiation insurers accept to pay the subjective compensation values of claimants, since these values are lower than their estimates of compensations at trial.
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Insects are the most diverse group of animals on the planet, comprising over 90% of all metazoan life forms, and have adapted to a wide diversity of ecosystems in nearly all environments. They have evolved highly sensitive chemical senses that are central to their interaction with their environment and to communication between individuals. Understanding the molecular bases of insect olfaction is therefore of great importance from both a basic and applied perspective. Odorant binding proteins (OBPs) are some of most abundant proteins found in insect olfactory organs, where they are the first component of the olfactory transduction cascade, carrying odorant molecules to the olfactory receptors. We carried out a search for OBPs in the genome of the parasitoid wasp Nasonia vitripennis and identified 90 sequences encoding putative OBPs. This is the largest OBP family so far reported in insects. We report unique features of the N. vitripennis OBPs, including the presence and evolutionary origin of a new subfamily of double-domain OBPs (consisting of two concatenated OBP domains), the loss of conserved cysteine residues and the expression of pseudogenes. This study also demonstrates the extremely dynamic evolution of the insect OBP family: (i) the number of different OBPs can vary greatly between species; (ii) the sequences are highly diverse, sometimes as a result of positive selection pressure with even the canonical cysteines being lost; (iii) new lineage specific domain arrangements can arise, such as the double domain OBP subfamily of wasps and mosquitoes.
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OBJECTIVES: The aims of this study were to determine the etiology, clinical features, and predictors of outcome of new-onset refractory status epilepticus. METHODS: Retrospective review of patients with refractory status epilepticus without etiology identified within 48 hours of admission between January 1, 2008, and December 31, 2013, in 13 academic medical centers. The primary outcome measure was poor functional outcome at discharge (defined as a score >3 on the modified Rankin Scale). RESULTS: Of 130 cases, 67 (52%) remained cryptogenic. The most common identified etiologies were autoimmune (19%) and paraneoplastic (18%) encephalitis. Full data were available in 125 cases (62 cryptogenic). Poor outcome occurred in 77 of 125 cases (62%), and 28 (22%) died. Predictors of poor outcome included duration of status epilepticus, use of anesthetics, and medical complications. Among the 63 patients with available follow-up data (median 9 months), functional status improved in 36 (57%); 79% had good or fair outcome at last follow-up, but epilepsy developed in 37% with most survivors (92%) remaining on antiseizure medications. Immune therapies were used less frequently in cryptogenic cases, despite a comparable prevalence of inflammatory CSF changes. CONCLUSIONS: Autoimmune encephalitis is the most commonly identified cause of new-onset refractory status epilepticus, but half remain cryptogenic. Outcome at discharge is poor but improves during follow-up. Epilepsy develops in most cases. The role of anesthetics and immune therapies warrants further investigation.
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PURPOSE: To assess the prevalence of PRPH2 in autosomal dominant retinitis pigmentosa (adRP), to report 6 novel mutations, to characterize the biochemical features of a recurrent novel mutation, and to study the clinical features of adRP patients. DESIGN: Retrospective clinical and molecular genetic study. METHODS: Clinical investigations included visual field testing, fundus examination, high-resolution spectral-domain optical coherence tomography (OCT), fundus autofluorescence imaging, and electroretinogram (ERG) recording. PRPH2 was screened by Sanger sequencing in a cohort of 310 French families with adRP. Peripherin-2 protein was produced in yeast and analyzed by Western blot. RESULTS: We identified 15 mutations, including 6 novel and 9 previously reported changes in 32 families, accounting for a prevalence of 10.3% in this adRP population. We showed that a new recurrent p.Leu254Gln mutation leads to protein aggregation, suggesting abnormal folding. The clinical severity of the disease in examined patients was moderate with 78% of the eyes having 1-0.5 of visual acuity and 52% of the eyes retaining more than 50% of the visual field. Some patients characteristically showed vitelliform deposits or macular involvement. In some families, pericentral RP or macular dystrophy were found in family members while widespread RP was present in other members of the same families. CONCLUSIONS: The mutations in PRPH2 account for 10.3% of adRP in the French population, which is higher than previously reported (0%-8%) This makes PRPH2 the second most frequent adRP gene after RHO in our series. PRPH2 mutations cause highly variable phenotypes and moderate forms of adRP, including mild cases, which could be underdiagnosed.
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Aim of the study: Mycorrhizal fungi in Mediterranean forests play a key role in the complex process of recovery after wildfires. A broader understanding of an important pyrophytic species as Pinus pinaster and its fungal symbionts is thus necessary for forest restoration purposes. This study aims to assess the effects of ectomycorrhizal symbiosis on maritime pine seedlings and how fire severity affects fungal colonization ability. Area of study: Central Spain, in a Mediterranean region typically affected by wildfires dominated by Pinus pinaster, a species adapted to fire disturbance. Material and Methods: We studied P. pinaster root apexes from seedlings grown in soils collected one year after fire in undisturbed sites, sites moderately affected by fire and sites highly affected by fire. Natural ectomycorrhization was observed at the whole root system level as well as at two root vertical sections (0-10 cm and 10-20 cm). We also measured several morphometric traits ( tap root length, shoot length, dry biomass of shoots and root/shoot ratio), which were used to test the influence of fire severity and soil chemistry upon them. Main results: Ectomycorrhizal colonization in undisturbed soils for total and separated root vertical sections was higher than in soils that had been affected by fire to some degree. Inversely, seedling vegetative size increased according to fire severity. Research highlights: Fire severity affected soil properties and mycorrhizal colonization one year after occurrence, thus affecting plant development. These findings can contribute to a better knowledge of the factors mediating successful establishment of P. pinaster in Mediterranean forests after wildfires.
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In this paper the authors propose a new closed contour descriptor that could be seen as a Feature Extractor of closed contours based on the Discrete Hartley Transform (DHT), its main characteristic is that uses only half of the coefficients required by Elliptical Fourier Descriptors (EFD) to obtain a contour approximation with similar error measure. The proposed closed contour descriptor provides an excellent capability of information compression useful for a great number of AI applications. Moreover it can provide scale, position and rotation invariance, and last but not least it has the advantage that both the parameterization and the reconstructed shape from the compressed set can be computed very efficiently by the fast Discrete Hartley Transform (DHT) algorithm. This Feature Extractor could be useful when the application claims for reversible features and when the user needs and easy measure of the quality for a given level of compression, scalable from low to very high quality.
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Objectives: To describe the clinical features of patients diagnosed with oral lichen planus (OLP) and to establish the prevalence of its malignant transformation in our setting. Study design: A retrospective study was made of 65 patients clinically and histologically diagnosed with OLP in the Service of Oral Surgery (Dental Clinic of the University of Barcelona, Spain) in the period 1990-2005. A descriptive and bivariate statistical analysis was made. Results: The mean patient age was 59 years (SD ± 14.9). Most of the patients (61%) were women, and the most frequent location of the lesions was the buccal mucosa (90.8%). White forms of OLP were noted in 66% of the cases, and 46.2% of the patients reported symptoms of some kind. The patients diagnosed with diabetes mellitus (20%) showed a larger proportion of red lesions (p=0.088). No statistically significant association was observed between chronic liver disease and the OLP lesion types or symptoms. Two cases of squamous cell carcinoma were identified in two patients previously or simultaneously diagnosed with OLP. A statistically significant correlation was observed between dysplastic changes / malignization of the lesions and smoking habit (p=0.019). An association to alcohol abuse was also noted, though in this case statistical significance was not reached (p=0.085). Conclusions: The clinical features of our study population were similar to those described in other studies. Diabetic patients with OLP were seen to be more susceptible to the development of atrophic-erosive lesions. Smokers and/or patients with alcohol abuse in turn showed a greater tendency to develop dysplastic changes / malignization in the histopathological study of the lesions
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Objectives: The purpose of this study was to determine the incidence and clinical symptoms associated with sharp mandibular bone irregularities (SMBI) after lower third molar extraction and to identify possible risk factors for this complication. Study Design: A mixed study design was used. A retrospective cohort study of 1432 lower third molar extractions was done to determine the incidence of SMBI and a retrospective case-control study was done to determine potential demographic and etiologic factors by comparing those patients with postoperative SMBI with controls. Results: Twelve SMBI were found (0.84%). Age was the most important risk factor for this complication. The operated side and the presence of an associated radiolucent image were also significantly related to the development of mandibular bone irregularities. The depth of impaction of the tooth might also be an important factor since erupted or nearly erupted third molars were more frequent in the SMBI group. Conclusions: SMBI are a rare postoperative complication after lower third molar removal. Older patients having left side lower third molars removed are more likely to develop this problem. The treatment should be the removal of the irregularity when the patient is symptomatic
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Pro-gradu –tutkielmani aiheena ovat 1700-luvun ”karanneet orjat” – sanomalehtiilmoitusten genrelle ominaiset piirteet. Tutkimusaineisto koostuu 190 ilmoituksesta, jotka ovat alkuperäisesti ilmestyneet virginialaisissa, pennsylvanialaisissa ja newyorkilaisissa sanomalehdissä 1730-luvulta 1770-luvulle. Tutkimuksen kohteeksi on rajattu ilmoitukset, joissa yksityishenkilöt ilmoittavat orjan/orjien karanneet ja lupaavat kiinniottajalle palkkion. Tutkielman tarkoituksena on tarkastella, millaisia ovat tyypilliset kielelliset piirteet näissä teksteissä ja millainen on prototyyppinen genren edustaja. Genreteorian lisäksi teoriaosuudessa käsittelen jonkin verran 1700- luvun englannin kielen yleisiä piirteitä sekä orjuuden ja sanomalehtien syntyhistoriaa Amerikassa taustoittaakseni tutkimusta. Analyysissa hyödynnän mm. Swalesin ja Bhatian käyttämää käsitettä siirroista (moves). Tutkin ilmoituksien tyypillistä rakennetta jakamalla ne yhdeksään siirtoon, joilla kaikilla on oma tehtävänsä ilmoituksessa. Jotkut siirrot, kuten karkulaisen kuvailu ja palkkion lupaaminen, esiintyvät kaikissa ilmoituksissa, kun taas toiset siirrot ovat läsnä harvemmin. Muita tälle genrelle tyypillisiä ominaisuuksia ovat esim. ilmoituksissa toistuvat kiinteät fraasit ja tietyt sanastolliset erikoisuudet. Lisäksi tutkin ilmoituksissa käytettäviä tapoja viitata asiaan liittyviin henkilöihin, sekä erilaisia toimia, joita ilmoitusten jättäjät ilmoituksien avulla suorittavat. Genressä on havaittavissa pieniä reilun neljänkymmenen vuoden kuluessa tapahtuneita muutoksia, mutta myös eroavaisuuksia eri siirtokuntien ilmoitusten välillä. Yleisesti voidaan todeta, että vaikka ”karanneet orjat” –ilmoitukset voivat vaihdella rakenteeltaan ja sanavalinnoiltaan, suuri osa ilmoituksista seuraa kuitenkin melko prototyyppistä muottia.
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The promotion of energy-efficient appliances is necessary to reduce the energetic and environmental burden of the household sector. However, many studies have reported that a typical consumer underestimates the benefits of energy-saving investment on the purchase of household electric appliances. To analyze this energy-efficiency gap problem, many scholars have estimated implicit discount rates that consumers use for energy-consuming durables. Although both hedonic and choice models have been used in previous studies, a comparison between two models has not yet been done. This study uses point of sale data about Japanese residential air conditioners and estimates implicit discounts rates with both hedonic and choice models. Both models demonstrate that a typical consumer underinvests in energy efficiency. Although choice models estimate a lower implicit discount rate than hedonic models, the latter models estimate the values of other product characteristics more consistently than choice models.
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This Master's thesis studies the development of interaction and socialization in online communities. A large number of online communities fade away even before they really get started. In many occasions the reason is that the community does not give anything new, or even if they do, the delivery does not satisfy the users. In this thesis guidelines were developed to help to see important things, which might be forgotten when developing an online community. The thesis goes through the characteristic of an online community and human behaviour related to them and also compares behaviour in the Internet and real life. In addition, usability is an important part of the online communities and thus it is also covered in this thesis. As a result of this thesis an 8-step guideline was developed to ease the design of an online community. Guidelines were also applied to two real life cases which are described as one part of this work.
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Determination of virus diversity in the field is vital to support a sustainable breeding program for virus resistance of horticultural crops. The present study aimed to characterize four field potyvirus isolates found naturally infecting sweet pepper (Capsicum annuum) (Sa66 and Sa115) and tomato (Lycopersicon esculentum) (IAC3 and Sa21) plants. Their biological characteristics revealed differences among the isolates in their ability to infect distinct Capsicum spp. and tomato genotypes, and in the severity of symptoms caused by these isolates compared to the infection caused by an isolate of Pepper yellow mosaic virus (PepYMV). Absence of cross-reaction was found among the studied isolates with antiserum against Potato virus Y (PVY). However, all isolates reacted, at different intensities, with antiserum against PepYMV. All isolates showed high identity percentage (97 to 99%) of the amino acid sequence of the coat protein with PepYMV (accession AF348610) and low (69 to 80%) with other potyvirus species. The comparison of the 3' untranslated region also confirmed this finding with 97 to 98% identity with PepYMV, and of 47 to 71% with other potyviruses. The results showed that PepYMV isolates were easily differentiated from PVY by serology and that the host response of each isolate could be variable. In addition, the nucleotide sequence of the coat protein and 3' untranslated region was highly conserved among the isolates.