56 resultados para ear recognition
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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Maize seeds developed at different portions of the ear of two hybrids (one, a large seeded, and the other a small seeded hybrid) were compared as to physical positions, morphological, and physiological characteristics viewing to gain information to be used during seed conditioning. The number of positions in the ear were 10, starting at the proximal and ending at the distal end. For the sake of simplification, the data were combined to refer to seeds of the proximal, the central and the distal sectors of an ear. Measurements made of the seeds as to shape (length, width, and thickness) and as to size (1,000 seeds weight) indicated that the round seeds growing at the distal sector are significantly smaller (mainly when thickness is considered) and lighter than those growing at the proximal sector. on the other hand, determinations of the physiological quality indicated that the round-proximal and the central seeds are equivalent and both significantly superior to the round-distal ones, Considering these significant differences as to size, shape, and physiological quality, a proposition of suppressing part of the round-distal from the totallity of the round seeds during the operations of seed conditioning is made.
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Most face recognition approaches require a prior training where a given distribution of faces is assumed to further predict the identity of test faces. Such an approach may experience difficulty in identifying faces belonging to distributions different from the one provided during the training. A face recognition technique that performs well regardless of training is, therefore, interesting to consider as a basis of more sophisticated methods. In this work, the Census Transform is applied to describe the faces. Based on a scanning window which extracts local histograms of Census Features, we present a method that directly matches face samples. With this simple technique, 97.2% of the faces in the FERET fa/fb test were correctly recognized. Despite being an easy test set, we have found no other approaches in literature regarding straight comparisons of faces with such a performance. Also, a window for further improvement is presented. Among other techniques, we demonstrate how the use of SVMs over the Census Histogram representation can increase the recognition performance.
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The binding selectivity of the M(phen)(edda) (M = Cu, Co, Ni, Zn; phen = 1,10-phenanthroline, edda = ethylenediaminediacetic acid) complexes towards ds(CG)(6), ds(AT)(6) and ds(CGCGAATTCGCG) B-form oligonucleotide duplexes were studied by CD spectroscopy and molecular modeling. The binding mode is intercalation and there is selectivity towards AT-sequence and stacking preference for A/A parallel or diagonal adjacent base steps in their intercalation. The nucleolytic properties of these complexes were investigated and the factors affecting the extent of cleavage were determined to be: concentration of complex, the nature of metal(11) ion, type of buffer, pH of buffer, incubation time, incubation temperature, and the presence of hydrogen peroxide or ascorbic acid as exogenous reagents. The fluorescence property of these complexes and its origin were also investigated. The crystal structure of the Zn(phen)(edda) complex is reported in which the zinc atom displays a distorted trans-N4O2 octahedral geometry; the crystal packing features double layers of complex molecules held together by extensive hydrogen bonding that inter-digitate with adjacent double layers via pi...pi interactions between 1,10-phenanthroline residues. The structure is compared with that of the recently described copper(II) analogue and, with the latter, included in molecular modeling. (C) 2008 Elsevier B.V. All rights reserved.
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INTRODUCTION: Peripheral arterial disease is a severe manifestation of atherosclerosis that can lead to critical ischemia of the lower limbs and is also associated with high cardiovascular risk. Diagonal lobular and anterior tragal ear creases have been associated with coronary artery disease, but they have not yet been investigated in patients with peripheral arterial disease.OBJECTIVES: To evaluate the prevalence of ear creases among patients with peripheral arterial disease of the lower limbs, compared with patients without documented atherosclerotic disease.METHODS: Cross-sectional study including 60 male patients with peripheral arterial disease of the lower limbs and 60 dermatologic outpatients matched for age and gender. The associations were adjusted for other risk factors by conditional logistic regression.RESULTS: The prevalence of diagonal and anterior tragal ear creases was higher among cases (73% vs. 25% and 80% vs. 43%, respectively) than controls; these associations remained significant even when adjusting for other known risk factors of atherosclerosis (odds ratio = 8.1 and 4.1, respectively).CONCLUSIONS: Ear creases are independently associated with peripheral arterial disease and may be an external marker for risk identification.
Resumo:
Background: The absence of an ear, which can be the result of a congenital malformation, surgical tumour resection or traumatic injury, is a significant aesthetic problem. Attachment of ear prostheses with adhesives can cause local irritation for the wearer and affect the colour of the prostheses. Use of implants in craniofacial reconstruction can improve the retention and stability of prostheses giving to patient greater comfort and security relative to adhesive attachment.Objective: The aim of this report was to present a clinical case of a mutilated patient who was rehabilitated by means of installing an ear prosthesis fixed through osseointegrated implants.Materials and methods: The patient had two implants installed in the mastoid region that were linked by a bar, and a clip-type system was used. The ear prosthesis was constructed from medical-use silicone, pigmented to match the patient's skin colour and linked to the retention system.Conclusion: The patient's rehabilitation was satisfactory from both a functional and an aesthetic point of view, making it possible for the patient to return to a normal social life and regain lost self-esteem.
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The nuclear import of simian-virus-40 large T-antigen (tumour antigen) is enhanced via phosphorylation by the protein kinase CK2 at Ser(112) in the vicinity of the NLS (nuclear localization sequence). To determine the structural basis of the effect of the sequences flanking the basic cluster KKKRK, and the effect of phosphorylation on the recognition of the NLS by the nuclear import factor importin-alpha (Impalpha), we co-crystallized non-autoinhibited Impalpha with peptides corresponding to the phosphorylated and non-phosphorylated forms of the NLS, and determined the crystal structures of the complexes. The structures show that the amino acids N-terminally flanking the basic cluster make specific contacts with the receptor that are distinct from the interactions between bipartite NLSs and Impalpha. We confirm the important role of flanking sequences using binding assays. Unexpectedly, the regions of the peptides containing the phosphorylation site do not make specific contacts with the receptor. Binding assays confirm that phosphorylation does not increase the affinity of the T-antigen NLS to Impalpha. We conclude that the sequences flanking the basic clusters in NLSs play a crucial role in nuclear import by modulating the recognition of the NLS by Impalpha, whereas phosphorylation of the T-antigen enhances nuclear import by a mechanism that does not involve a direct interaction of the phosphorylated residue with Impalpha.
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Perceiving a possible predator may promote physiological changes to support prey 'fight or flight'. In this case, an increase in ventilatory frequency (VF) may be expected, because this is a way to improve oxygen uptake for escape tasks. Therefore, changes in VF may be used as a behavioral tool to evaluate visual recognition of a predator threat. Thus, we tested the effects of predator visual exposure on VF in the fish Nile tilapia, Oreochromis niloticus. For this, we measured tilapia VF before and after the presentation of three stimuli: an aquarium with a harmless fish or a predator or water (control). Nile tilapia VF increased significantly in the group visually exposed to a predator compared with the other two, which were similar to each other. Hence, we conclude that Nile tilapia may recognize an allopatric predator; consequently VF is an effective tool to indicate visual recognition of predator threat in fish. (C) 2002 Elsevier B.V. B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The merozoite surface protein-2 (MSP-2) of Plasmodium falciparum comprises repeats flanked by dimorphic domains defining the allelic families FC27 and IC1. Here, we examined sequence diversity at the msp-2 locus in Brazil and its impact on MSP-2 antibody recognition by local patients. Only 25 unique partial sequences of msp-2 were found in 61 isolates examined. The finding of identical msp-2 sequences in unrelated parasites, collected 6-13 years apart, suggests that no major directional selection is exerted by variant-specific immunity in this malaria-endemic area. To examine antibody cross-reactivity, recombinant polypeptides derived from locally prevalent and foreign MSP-2 variants were used in ELISA. Foreign IC1-type variants, such as 3D7 (currently tested for human vaccination), were less frequently recognized than FC27-type and local IC1-type variants. Antibodies discriminated between local and foreign IC1-type variants, but cross-recognized structurally different local IC1-type variants. The use of evolutionary models of MSP-2 is suggested to design vaccines that minimize differences between local parasites and vaccine antigens. (C) 2004 Elsevier B.V. All rights reserved.
Resumo:
The anti-inflammatory activity of 14 commercial ethanol extracts of propolis were evaluated, using a mouse ear inflammation model induced by arachidonic acid. Indometacin was also assayed as standard anti-inflammatory agent. Different activities were observed and discussed. This model could be used to assess the anti-inflammatory quality of propolis extracts and facilitate their posological usage on skin edema resulting from wounds.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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NAPc2, an anticoagulant protein from the hematophagous nematode Ancylostoma caninum evaluated in phase-II/IIa clinical trials, inhibits the extrinsic blood coagulation pathway by a two step mechanism, initially interacting with the hitherto uncharacterized factor Xa exosite involved in macromolecular recognition and subsequently inhibiting factor VIIa (K-i = 8.4 pM) of the factor VIIa/tissue factor complex. NAPc2 is highly flexible, becoming partially ordered and undergoing significant structural changes in the C terminus upon binding to the factor Xa exosite. In the crystal structure of the ternary factor Xa/NAPc2/selectide complex, the binding interface consists of an intermolecular antiparallel beta-sheet formed by the segment of the polypeptide chain consisting of residues 74-80 of NAPc2 with the residues 86-93 of factor Xa that is additional maintained by contacts between the short helical segment (residues 67-73) and a turn (residues 26-29) of NAPc2 with the short C-terminal helix of factor Xa (residues 233-243). This exosite is physiologically highly relevant for the recognition and inhibition of factor X/Xa by macromolecular substrates and provides a structural motif for the development of a new class of inhibitors for the treatment of deep vein thrombosis and angioplasty. (c) 2006 Elsevier Ltd. All rights reserved.
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Some molecular properties are described of Cole latent virus (CoLV), hitherto designated a tentative species of the Carlavirus genus. CoLV genomic RNA (Ribonucleic acid) of 8.3 Kb is polyadenylated. Two unencapsidated polyadenylated subgenomic RNAs (2.6 and 1.3 Kb) and three double-stranded RNAs (dsRNAs) (8.3, 2.6 and 1.3 Kbp), which are twice the size of the genomic and subgenomics ssRNAs, are produced in CoLV-infected plants, two additional dsRNAs (7.2 and 6.3 Kbp) were also detected plant extracts. By using a Carlavirus specific primer and a CoLV cDNA, a-3'-terminus fragment of 116 bp was amplified; it had homology with the carlaviruses Potato virus M (62%)., Hop latent virus (37%) and Blueberry scorch virus (36%) but no significant homology with 11 other carlaviruses. These results support the classification of CoLV as a distinct species of the Carlavirus genus.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)