885 research outputs found

    Image similarity in medical images

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    Recent experiments have indicated a strong influence of the substrate grain orientation on the self-ordering in anodic porous alumina. Anodic porous alumina with straight pore channels grown in a stable, self-ordered manner is formed on (001) oriented Al grain, while disordered porous pattern is formed on (101) oriented Al grain with tilted pore channels growing in an unstable manner. In this work, numerical simulation of the pore growth process is carried out to understand this phenomenon. The rate-determining step of the oxide growth is assumed to be the Cabrera-Mott barrier at the oxide/electrolyte (o/e) interface, while the substrate is assumed to determine the ratio β between the ionization and oxidation reactions at the metal/oxide (m/o) interface. By numerically solving the electric field inside a growing porous alumina during anodization, the migration rates of the ions and hence the evolution of the o/e and m/o interfaces are computed. The simulated results show that pore growth is more stable when β is higher. A higher β corresponds to more Al ionized and migrating away from the m/o interface rather than being oxidized, and hence a higher retained O:Al ratio in the oxide. Experimentally measured oxygen content in the self-ordered porous alumina on (001) Al is indeed found to be about 3% higher than that in the disordered alumina on (101) Al, in agreement with the theoretical prediction. The results, therefore, suggest that ionization on (001) Al substrate is relatively easier than on (101) Al, and this leads to the more stable growth of the pore channels on (001) Al

    Sersiclets - A Matched Filter Extension of Shapelets for Weak Lensing Studies

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    The precision study of dark matter using weak lensing by large scale structure is strongly constrained by the accuracy with which one can measure galaxy shapes. Several methods have been devised but none have demonstrated the ability to reach the level of precision required by future weak lensing surveys. In this Letter we explore new avenues to the existing Shapelets approach, combining a priori knowledge of the galaxy profile with the power of orthogonal basis function decomposition. This Letter discusses the new issues raised by this matched filter approach and proposes promising alternatives to shape measurement techniques. In particular it appears that the use of a matched filter (e.g. Sersic profile) restricted to elliptical radial fitting functions resolves several well known Shapelet issues.Comment: 6 pages, 6 figures. MNRAS Accepte

    Risk of cervical cancer is not increased in Chinese carrying homozygous arginine at codon 72 of p53

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    Homozygous arginine at codon 72 (HA72) of p53 was found in 22% of normal cervices and 30.0% of cervical cancers and no significant difference was detected between normal and cervical cancer with or without HPV 16/18. There was no correlation between HA72 and risk of cervical cancer in Chinese.link_to_subscribed_fulltex

    Família e ensino secundário: a colaboração e participação nas escolas do ensino público da Região Autónoma da Madeira

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    Hoje em dia é cada vez mais frequente ouvir falar na necessidade de uma maior aproximação entre as Famílias, a Escola e a Comunidade, pois são as três entidades que estão presentes, não só, durante as primeiras aprendizagens, mas também durante grande parte da vida do indivíduo. Sabemos que neste mundo globalizado, no qual as mudanças acontecem a todo o momento, cada vez mais competitivo, as famílias têm visto o seu tempo com as crianças ser reduzido de dia para dia, facto este que tem feito com que esta entidade se veja, quase, na obrigação de entregar os seus “meninos” às escolas, lhes delegando certas responsabilidades. É, por isso, premente e necessário conhecer a realidade em que se vive, e explorar os factores que estão envolvidos nesta problemática, de modo a criar condições para que exista a possibilidade de criar e desenvolver novas estratégias para atrair os pais à escola. É também importante desmistificar esta relação para que os receios de ambas as entidades, face à participação e envolvimento, sejam superados. O presente trabalho será desenvolvido na rede de escolas públicas da Região Autónoma da Madeira, distribuídas pelos vários concelhos e, vai incidir sobre o Ensino Secundário. A finalidade primordial é a de conhecer a realidade da participação no Ensino Secundário nas escolas da RAM, ou seja, compreender de que modo acontece, quem a promove e quem está implicado. Para tal recorremos à aplicação de questionários a uma amostra construída através do processo de amostragem por conveniência. Os dados obtidos permitiram-nos concluir que na nossa região a colaboração e participação acontecem independentemente do estatuto sócio-cultural. Esta participação é, sobretudo, indirecta, acontecendo raramente nas tomadas de decisão. Por último concluímos que os Presidentes dos Conselhos Executivos são quem apresenta um discurso mais favorável à participação e colaboração dos Encarregados de Educação.Universidade da Madeir

    Bitter Melon (Momordica charantia) Extract Inhibits Tumorigenicity and Overcomes Cisplatin-Resistance in Ovarian Cancer Cells Through Targeting AMPK Signaling Cascade

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    OBJECTIVE: Acquired chemoresistance is a major obstacle in the clinical management of ovarian cancer. Therefore, searching for alternative therapeutic modalities is urgently needed. Bitter melon (Momordica charantia) is a traditional dietary fruit, but its extract also shows potential medicinal values in human diabetes and cancers. Here, we sought to investigate the extract of bitter melon (BME) in antitumorigenic and cisplatin-induced cytotoxicity in ovarian cancer cells. METHODS: Three varieties of bitter melon were used to prepare the BME. Ovarian cancer cell lines, human immortalized epithelial ovarian cells (HOSEs), and nude mice were used to evaluate the cell cytotoxicity, cisplatin resistance, and tumor inhibitory effect of BME. The molecular mechanism of BME was examined by Western blotting. RESULTS: Cotreatment with BME and cisplatin markedly attenuated tumor growth in vitro and in vivo in a mouse xenograft model, whereas there was no observable toxicity in HOSEs or in nude mice in vivo. Interestingly, the antitumorigenic effects of BME varied with different varieties of bitter melon, suggesting that the amount of antitumorigenic substances may vary. Studies of the molecular mechanism demonstrated that BME activates AMP-activated protein kinase (AMPK) in an AMP-independent but CaMKK (Ca2+/calmodulin-dependent protein kinase)-dependent manner, exerting anticancer effects through activation of AMPK and suppression of the mTOR/p70S6K and/or the AKT/ERK/FOXM1 (Forkhead Box M1) signaling cascade. CONCLUSION: BME functions as a natural AMPK activator in the inhibition of ovarian cancer cell growth and might be useful as a supplement to improve the efficacy of cisplatin-based chemotherapy in ovarian cancer.published_or_final_versio

    The intra-nucleus integration of mitochondrial DNA (mtDNA)in cervical mucosa cells and its relation with c-myc expression

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    <p>Abstract</p> <p>Objective</p> <p>To explore the relationship between the integration of mitochondrial DNA(mtDNA) in the nuclei of cervical epithelium cells and the expression of c-myc.</p> <p>Methods</p> <p>The expression of c-myc protein was measured by immunohistochemical test in 40 cases of the uterine cervix cancer, 30 cases of cervical intraepithelial neoplasia (CIN) and 30 cases of normal cervical epithelium; the sequence of mtDNA in the nuclei was detected by in situ hybridization technique.</p> <p>Results</p> <p>The detection rates of mtDNA in the nuclei of cervical epithelium cells were 27.5%, 13.3% and 0% in cervical carcinoma, CIN, and normal cervical epithelium respectively. The expression rate of c-myc in cervical mucoma cells was 67% in the mtDNA sequence positive group and was significantly higher than that in the negative group (36%).</p> <p>Conclusion</p> <p>The integration of mtDNA into the nuclei of cervical epithelium cells may be involved in the carcinogenesis of cervical epithelium cells and the expression of c-myc might be related to the integration of mtDNA sequence into nuclei of cervical epithelium cells.</p

    OGLE-2012-BLG-0455/MOA-2012-BLG-206: Microlensing event with ambiguity in planetary interpretations caused by incomplete coverage of planetary signal

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    Characterizing a microlensing planet is done from modeling an observed lensing light curve. In this process, it is often confronted that solutions of different lensing parameters result in similar light curves, causing difficulties in uniquely interpreting the lens system, and thus understanding the causes of different types of degeneracy is important. In this work, we show that incomplete coverage of a planetary perturbation can result in degenerate solutions even for events where the planetary signal is detected with a high level of statistical significance. We demonstrate the degeneracy for an actually observed event OGLE-2012-BLG-0455/MOA-2012-BLG-206. The peak of this high-magnification event (Amax400)(A_{\rm max}\sim400) exhibits very strong deviation from a point-lens model with Δχ24000\Delta\chi^{2}\gtrsim4000 for data sets with a total number of measurement 6963. From detailed modeling of the light curve, we find that the deviation can be explained by four distinct solutions, i.e., two very different sets of solutions, each with a two-fold degeneracy. While the two-fold (so-called "close/wide") degeneracy is well-understood, the degeneracy between the radically different solutions is not previously known. The model light curves of this degeneracy differ substantially in the parts that were not covered by observation, indicating that the degeneracy is caused by the incomplete coverage of the perturbation. It is expected that the frequency of the degeneracy introduced in this work will be greatly reduced with the improvement of the current lensing survey and follow-up experiments and the advent of new surveys.Comment: 5 pages, 3 figures, ApJ accepte
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