485 research outputs found

    Análise espacial das mudanças na cobertura e uso das terras em Santarém e Belterra, Pará, Brasil: armadilhas metodológicas associadas.

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    Através de um estudo de caso, indicamos como a delimitação da área de estudo pode influenciar o resultado de análises multiescalares em processos espaciais de mudanças na cobertura e uso da terra na Amazônia. Partindo dos limites dos municípios de Santarém e Belterra no oeste do Estado do Pará, definimos três níveis de delimitação da área de estudo. O primeiro nível abrange uma região que foi arbitrariamente definida e denominada sub-região de Santarém e Belterra. O segundo nível, uma parte do primeiro, corresponde ao limite do entorno de lotes estabelecidos pelo INCRA na década de 1970, tratando-se portanto de uma área de ocupação consolidada. O terceiro nível corresponde às zonas de influência de quatro eixos viários inseridos dentro da área de ocupação consolidada, subdivididos em subáreas norte e sul, num total de oito subáreas do segundo nível de delimitação. Para cada nível, aplicamos métricas de paisagem sobre mapeamentos temáticos do satélite Landsat obtidos para os anos de 1986 a 2005 e as associamos com dados sociodemográficos obtidos em levantamentos realizados em 2003. Os resultados mostram que as peculiaridades da dinâmica de ocupação em cada nível permitem melhor identificar padrões e processos na composição da estrutura da paisagem. Os dados obtidos para os três níveis de delimitação são complementares, possibilitando uma compreensão mais abrangente do que aquela que se poderia obter pelo estudo de um único nível

    The helium spread in the Globular cluster 47 Tuc

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    Spectroscopy has shown the presence of the CN band dicothomy and the Na-O anticorrelations for 50--70% of the investigated samples in the cluster 47 Tuc, otherwise considered a "normal" prototype of high metallicity clusters from the photometric analysis. Very recently, the re-analysis of a large number of archival HST data of the cluster core has been able to put into evidence the presence of structures in the Sub Giant Branch: it has a brighter component with a spread in magnitude by \sim0.06 mag and a second one, made of about 10% of stars, a little fainter (by \sim0.05 mag). These data also show that the Main Sequence of the cluster has an intrinsic spread in color which, if interpreted as due to a small spread in helium abundance, suggests Δ\DeltaY\sim0.027. In this work we examine in detail whether the Horizontal Branch morphology and the Sub Giant structure provide further independent indications that a real --although very small-helium spread is present in the cluster. We re--analyze the HST archival data for the Horizontal Branch of 47 Tuc, obtaining a sample of \sim500 stars with very small photometric errors, and build population synthesis based on new models to show that its particular morphology can be better explained by taking into account a spread in helium abundance of 2% in mass. The same variation in helium is able to explain the spread in luminosity of the Sub Giant Branch, while a small part of the second generation is characterized by a small C+N+O increase and provides an explanation for the fainter Sub Giant Branch. We conclude that three photometric features concur to form the paradigm that a small but real helium spread is present in a cluster that has no spectacular evidence for multiple populations like those shown by other massive clusters.Comment: Accepted for publication in the MNRAS on 2010 June 8. Received 2010 May 19; in original form 2010 February 9. 7 pages and 3 figures. No table

    The first magnetic maps of a pre-main sequence binary star system - HD 155555

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    We present the first maps of the surface magnetic fields of a pre-main sequence binary system. Spectropolarimetric observations of the young, 18 Myr, HD 155555 (V824 Ara, G5IV + K0IV) system were obtained at the Anglo-Australian Telescope in 2004 and 2007. Both datasets are analysed using a new binary Zeeman Doppler imaging (ZDI) code. This allows us to simultaneously model the contribution of each component to the observed circularly polarised spectra. Stellar brightness maps are also produced for HD 155555 and compared to previous Doppler images. Our radial magnetic maps reveal a complex surface magnetic topology with mixed polarities at all latitudes. We find rings of azimuthal field on both stars, most of which are found to be non-axisymmetric with the stellar rotational axis. We also examine the field strength and the relative fraction of magnetic energy stored in the radial and azimuthal field components at both epochs. A marked weakening of the field strength of the secondary star is observed between the 2004 and 2007 epochs. This is accompanied by an apparent shift in the location of magnetic energy from the azimuthal to radial field. We suggest that this could be indicative of a magnetic activity cycle. We use the radial magnetic maps to extrapolate the coronal field (by assuming a potential field) for each star individually - at present ignoring any possible interaction. The secondary star is found to exhibit an extreme tilt (~75 deg) of its large scale magnetic field to that of its rotation axis for both epochs. The field complexity that is apparent in the surface maps persists out to a significant fraction of the binary separation. Any interaction between the fields of the two stars is therefore likely to be complex also. Modelling this would require a full binary field extrapolation.Comment: 17 pages, 12 figures, accepted for publication in MNRA

    POISSON project - II - A multi-wavelength spectroscopic and photometric survey of young protostars in L 1641

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    Characterising stellar and circumstellar properties of embedded young stellar objects (YSOs) is mandatory for understanding the early stages of the stellar evolution. This task requires the combination of both spectroscopy and photometry, covering the widest possible wavelength range, to disentangle the various protostellar components and activities. As part of the POISSON project, we present a multi-wavelength spectroscopic and photometric investigation of embedded YSOs in L1641, aimed to derive the stellar parameters and evolutionary stages and to infer their accretion properties. Our database includes low-resolution optical-IR spectra from the NTT and Spitzer (0.6-40 um) and photometric data covering a spectral range from 0.4 to 1100 um, which allow us to construct the YSOs spectral energy distributions (SEDs) and to infer the main stellar parameters. The SED analysis allows us to group our 27 YSOs into nine Class I, eleven Flat, and seven Class II objects. However, on the basis of the derived stellar properties, only six Class I YSOs have an age of ~10^5 yr, while the others are older 5x10^5-10^6 yr), and, among the Flat sources, three out of eleven are more evolved objects (5x10^6-10^7 yr), indicating that geometrical effects can significantly modify the SED shapes. Inferred mass accretion rates (Macc) show a wide range of values (3.6x10^-9 to 1.2x10^-5 M_sun yr^-1), which reflects the age spread observed in our sample. Average values of mass accretion rates, extinction, and spectral indices decrease with the YSO class. The youngest YSOs have the highest Macc, whereas the oldest YSOs do not show any detectable jet activity in either images and spectra. We also observe a clear correlation among the YSO Macc, M*, and age, consistent with mass accretion evolution in viscous disc models.Comment: 61 pages, 16 figures; A&A in pres

    A paradigmatic autistic phenotype associated with loss of PCDH11Y and NLGN4Y genes

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    Background: Most studies relative to Y chromosome abnormalities are focused on the sexual developmental disorders. Recently, a few studies suggest that some genes located on Y chromosome may be related to different neurodevelopment disorders. Case presentation: We report a child with sexual developmental disorder associated with a peculiar phenotype characterized by severe language impairment and autistic behaviour associated with a mosaicism [45,X(11)/46,XY(89)] and a partial deletion of the short and long arm of Y chromosome (del Yp11.31q11.23) that also involves the loss of both PCDH11Y and NLGN4Y genes. To our knowledge no study has ever reported the occurrence of the lack of both PCDH11Y and NLGN4Y located in the Y chromosome in the same patient. Conclusions: We hypothesized a functional complementary role of PCDH11Y and NLGN4Y within formation/maturation of the cerebral cortex. The impairment of early language development may be mainly related to the lack of PCDH11Y that underlies the early language network development and the later appearance of the autistic behaviour may be mainly related to deficit of inhibitory glicinergic neurotransmission NLGN4Y-linked

    Prevalence of emergency contraceptive pill use among Spanish adolescent girls and their family and psychological profiles

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    The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background:Adolescent girls’ family context and psychological characteristics play important roles in their sexual behavior, including the use of the emergency contraceptive pill (ECP). This study aims to (1) determine the prevalence of ECP use among girls who have had sexual intercourse and (2) comparatively analyze their family and psychological profiles according to whether they have used ECPs. Methods:The sample of 1735 Spanish girls aged 15 to 18 came from a representative sample of the 2014 edition of the Health Behaviour in School-aged Children (HBSC) study. Of this sample, 398 girls had sexual intercourse and reported their ECP use. Data collection for the HBSC study was performed through an online questionnaire to which adolescents responded anonymously in school. Data analyses were descriptive and bivariate and were performed with the statistical program IBM SPSS Statistics 23.Results:The results demonstrated that 30.65% of girls who had sexual intercourse used ECPs. Noticeable differences in paternal knowledge and communication with the father were observed between girls who used the ECP at least once and those who did not use it. In contrast, differences between girls who used the ECP once and those who used it twice or more were pronounced with regard to parental knowledge, communication with parents, maternal affection,life satisfaction, sense of coherence and depression. Conclusions:This work demonstrates a high prevalence of ECP use and a more positive family and psychological profile for girls who used ECP once compared with those who used it twice or more.Peer reviewedFinal Published versio

    NFIA haploinsufficiency: case series and literature review

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    Background: NFIA-related disorder (OMIM #613735) is an autosomal dominant neurodevelopmental disorder characterized by a variable degree of cognitive impairment and non-specific dysmorphic features. To date, fewer than thirty patients affected by this disorder have been described. Methods: Our study included three children with NFIA haploinsufficiency recruited from three medical genetics centers. Clinical presentations were recorded on a standardized case report form. Results: All patients presented a variable degree of intellectual disability. None of the individuals in our cohort had urinary tract malformations. Three novel mutations, c.344G>A, c.261T>G, and c.887_888del are reported here. Conclusion: NFIA haploinsufficiency can be suspected through careful observation of specific dysmorphisms, including macrocephaly and craniofacial abnormalities. Instrumental tests such as MRI and renal ultrasound provide further diagnostic clues, while genetic testing can confirm the diagnosis

    Commonalities and distinctions between two neurodevelopmental disorder subtypes associated with SCN2A and SCN8A variants and literature review

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    This study was aimed to analyze the commonalities and distinctions of voltage-gated sodium channels, Nav1.2, Nav1.6, in neurodevelopmental disorders. An observational study was performed including two patients with neurodevelopmental disorders. The demographic, electroclinical, genetic, and neuropsychological characteristics were analyzed and compared with each other and then with the subjects carrying the same genetic variants reported in the literature. The clinical features of one of them argued for autism spectrum disorder and developmental delay, the other for intellectual disability, diagnoses confirmed by the neuropsychological assessment. The first patient was a carrier of SCN2A (p.R379H) variant while the second was carrier of SCN8A (p.E936K) variant, both involving the pore loop of the two channels. The results of this study suggest that the neurodevelopmental disorders without overt epilepsy of both patients can be the consequences of loss of function of Nav1.2/Nav1.6 channels. Notably, the SCN2A variant, with an earlier expression timing in brain development, resulted in a more severe phenotype as autism spectrum disorder and developmental delay, while the SCN8A variant, with a later expression timing, resulted in a less severe phenotype as intellectual disability

    UPO Biobank: The Challenge of Integrating Biobanking into the Academic Environment to Support Translational Research

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    Biobanks are driving motors of precision and personalized medicine by providing high-quality biological material/data through the standardization and harmonization of their collection, preservation, and distribution. UPO Biobank was established in 2020 as an institutional, disease, and population biobank within the University of Piemonte Orientale (UPO) for the promotion and support of high-quality, multidisciplinary studies. UPO Biobank collaborates with UPO researchers, sustaining academic translational research, and supports the Novara Cohort Study, a longitudinal cohort study involving the population in the Novara area that will collect data and biological specimens that will be available for epidemiological, public health, and biological studies on aging. UPO Biobank has been developed by implementing the quality standards for the field and the ethical and legal issues and normative about privacy protection, data collection, and sharing. As a member of the "Biobanking and Biomolecular Resources Research Infrastructure" (BBMRI) network, UPO Biobank aims to expand its activity worldwide and launch cooperation with new national and international partners and researchers. The objective of this manuscript is to report an institutional and operational experience through the description of the technical and procedural solutions and ethical and scientific implications associated with the establishment of this university research biobank

    Kombinasi Format Factory, U-lead dan Microsoft Office Powerpoint dalam Upaya Meningkatkan Kualitas Media Pembelajaran

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    Peserta didik mempunyai gaya belajar yang berbeda-beda. Gaya belajar tersebut meliputi auditori, visual dan kinestetik (VAK). Seorang guru harus mampu memenuhi kebutuhan masing-masing gaya belajar peserta didik tersebut. Salah satu cara yang dapat dilakukan adalah dengan menggunakan media pembelajaran berbasis VAK. Media pembelajaran berbasis VAK dapat dipenuhi dengan menyisipkan file video di dalamnya. Selain itu, penggunaan file video sebagai media pembelajaran mendukung implementasi pembelajaran saintifik pada kurikulum 2013. Namun, belum semua guru memiliki kemampuan untuk mengemas file video tersebut dalam bentuk media pembelajaran. Tujuan penelitian ini adalah untuk meningkatkan kemampuan guru-guru di SMA Negeri 1 Teras dan SMA Negeri 1 Boyolali dalam membuat media pembelajaran berbasis VAK dengan kombinasi software Format Factory, U-Lead dan PowerPoint. Hasil penelitian menunjukkan bahwa terjadi peningkatan kemampuan para guru di SMA Negeri 1 Teras dan SMA Negeri 1 Boyolali dalam membuat media pembelajaran. Peningkatan kemampuan guru-guru tersebut berada di atas target yang direncanakan. Rerata peningkatan kemampuan guru-guru di SMA Negeri 1 Teras 7,87% di atas target, sedangkan di SMA Negeri 1 Boyolali 9,58% di atas target. Kata kunci: Media Pembelajaran, Format Factory, U-Lead, PowerPoint Students have different learning styles. Learning styles include visual learners, auditory learners, and kinesthetic learners. A teacher must be able to fulfill the needs of individual students\u27 learning styles. One way that can be applied is using Visual, Audio and Kinesthetic (VAK) learning media based. VAK-learning media based can be created by inserting video files on it. In addition, using video file as a learning media can support the implementation of scientific learning on the 2013 curriculum. However, not all teachers have the ability to use video files into a learning media. The purpose of this study is to improve the teachers\u27 ability at SMA Negeri 1 Teras and SMAN 1 Boyolali on making VAK-learning media based with a combination of Format Factory, U-Lead and PowerPoint software. The results showed that the teachers\u27 ability on making VAK-learning media based was increased. Increased the teachers\u27 ability was above planned target score. The mean score of the teachers\u27 ability at SMA Negeri 1 Teras 7.87% above the target, while at SMAN 1 Boyolali 9.58% above the target
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