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Redesigning the Way Basic Biostatistics Is Trained to the Undergraduate Degree in Aquatic Sciences: A Blended Learning Approach

Margarida Fonseca Cardoso; Teresa Correia
Fonte: Universidade do Porto Publicador: Universidade do Porto
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
65.56%
The undergraduate degree in Aquatic Sciences was reformulated recently according to the Bologna Process.As in any other degree in applied biology, students are required to satisfy a biostatistics requirement. New educational technologies such as Moodle are available in the University of Porto as a tool to promote the blended learning experience among the academic community. This was an excellent opportunity to change the learning process. In redesigning this course, the classical programme in basic biostatistics was maintained but emphasis was given to the problem solving component. The exposition to small biological problems explored both theoretical and practical aspects of biostatistics, including verbal and written communication. A final assignment with the collaboration of researchers from the Centre of Marine and Environmental Research (CIIMAR) gave them a first insight into the professional world in the Aquatic Sciences area. A Forum gave the opportunity to contact the teacher whenever necessary, to ask questions about the assignments and exam, but was also a way to involve students in the learning process. The success achieved with this experience of blended learning has shown its potential in teaching different biostatistics courses.

Docosahexaenoic acid-containing phospholipid molecular species in brains of vertebrates

Farkas, Tibor; Kitajka, Klara; Fodor, Elfrieda; Csengeri, István; Lahdes, Eila; Yeo, Young K.; Krasznai, Zoltán; Halver, John E.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.45%
The fatty acid composition of phospholipids and the contents of docosahexaenoic acid (DHA)-containing diacyl phosphatidylcholine and diacyl phosphatidylethanolamine molecular species were determined from brains of five fresh-water fish species from a boreal region adapted to 5°C, five fresh-water fish species from a temperate region acclimated to 5°C, five fresh-water fish species from a temperate region acclimated to 20°C, and three fresh water fish species from a subtropic region adapted to 25–26°C, as well as six mammalian species and seven bird species. There was little difference in DHA levels of fish brains from the different thermal environments; mammalian and bird brain phospholipids contained a few percentage points less DHA than those of the fish investigated. Molecular species of 22:6/22:6, 22:6/20:5, 22:6/20:4, 16:0/22:6, 18:0/22:6, and 18:1/22:6 were identified from all brain probes, and 16:0/22:6, 18:0/22:6, and 18:1/22:6 were the dominating species. Cold-water fish brains were rich in 18:1/22:6 diacyl phosphatidylethanolamine (and, to a lesser degree, in diacyl phosphatidylcholine), and its level decreased with increasing environmental/body temperature. The ratio of 18:0/22:6 to 16:0/22:6 phosphatidylcholine and phosphatidylethanolamine was inversely related to body temperature. Phospholipid vesicles from brains of cold-acclimated fish were more fluid...

Localization of guanylate cyclase-activating protein 2 in mammalian retinas

Otto-Bruc, Annie; Fariss, Robert N.; Haeseleer, Françoise; Huang, Jing; Surgucheva, Janina BuczyŁko*, Irina; Baehr, Wolfgang; Milam, Ann H.; Palczewski, Krzysztof
Fonte: The National Academy of Sciences of the USA Publicador: The National Academy of Sciences of the USA
Tipo: Artigo de Revista Científica
Publicado em 29/04/1997 EN
Relevância na Pesquisa
65.45%
Guanylate cyclase-activating proteins (GCAP1 and GCAP2) are thought to mediate the intracellular stimulation of guanylate cyclase (GC) by Ca2+, a key event in recovery of the dark state of rod photoreceptors after exposure to light. GCAP1 has been localized to rod and cone outer segments, the sites of phototransduction, and to photoreceptor synaptic terminals and some cone somata. We used in situ hybridization and immunocytochemistry to localize GCAP2 in human, monkey, and bovine retinas. In human and monkey retinas, the most intense immunolabeling with anti-GCAP2 antibodies was in the cone inner segments, somata, and synaptic terminals and, to a lesser degree, in rod inner segments and inner retinal neurons. In bovine retina, the most intense immunolabeling was in the rod inner segments, with weaker labeling of cone myoids, somata, and synapses. By using a GCAP2-specific antibody in enzymatic assays, we confirmed that GCAP1 but not GCAP2 is the major component that stimulates GC in bovine rod outer segment homogenates. These results suggest that although GCAP1 is involved in the Ca2+-sensitive regulation of GC in rod and cone outer segments, GCAP2 may have non-phototransduction functions in photoreceptors and inner retinal neurons.

Simple neural networks for the amplification and utilization of small changes in neuron firing rates

Adair, Robert K.
Fonte: The National Academy of Sciences Publicador: The National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.45%
I describe physiologically plausible “voter-coincidence” neural networks such that secondary “coincidence” neurons fire on the simultaneous receipt of sufficiently large sets of input pulses from primary sets of neurons. The networks operate such that the firing rate of the secondary, output neurons increases (or decreases) sharply when the mean firing rate of primary neurons increases (or decreases) to a much smaller degree. In certain sensory systems, signals that are generally smaller than the noise levels of individual primary detectors, are manifest in very small increases in the firing rates of sets of afferent neurons. For such systems, this kind of network can act to generate relatively large changes in the firing rate of secondary “coincidence” neurons. These differential amplification systems can be cascaded to generate sharp, “yes–no” spike signals that can direct behavioral responses.

Genetics of P450 oxidoreductase: Sequence variation in 842 individuals of four ethnicities and activities of 15 missense mutations

Huang, Ningwu; Agrawal, Vishal; Giacomini, Kathleen M.; Miller, Walter L.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.45%
P450 oxidoreductase (POR) is an electron-donating flavoprotein required for the activity of all microsomal cytochrome P450 enzymes. We sequenced 5,655 bp of the POR gene in a representative population of 842 healthy unrelated individuals in four ethnic groups: 218 African Americans, 260 Caucasian Americans, 179 Chinese Americans, and 185 Mexican Americans. One hundred forty SNPs were detected, of which 43 were found in ≥1% of alleles. Twelve SNPs were in the POR promoter region. Fifteen of 32 exonic variations altered the POR amino acid sequence; 13 of these 15 are previously undescribed missense variations. We found eight indels, only one of which was in the coding region. A previously described variant, A503V, was found on 27.9% of all alleles with some ethnic predilection (19.1% in African Americans, 26.4% in Caucasian Americans, 36.7% Chinese Americans, and 31.0% in Mexican Americans). We built cDNA expression vectors for the 13 previously undescribed missense variants, expressed each protein lacking 27 N-terminal residues in Escherichia coli, and assayed the apparent Km and Vmax of each in four assays: reduction of cytochrome c, oxidation of NADPH, 17α-hydroxylase activity of P450c17, and 17,20 lyase activity of P450c17. The catalytic activities of several missense mutants differed substantially in these assays...

Anthropogenic increase in carbon dioxide compromises plant defense against invasive insects

Zavala, Jorge A.; Casteel, Clare L.; DeLucia, Evan H.; Berenbaum, May R.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.45%
Elevated levels of atmospheric carbon dioxide (CO2), a consequence of anthropogenic global change, can profoundly affect the interactions between crop plants and insect pests and may promote yet another form of global change: the rapid establishment of invasive species. Elevated CO2 increased the susceptibility of soybean plants grown under field conditions to the invasive Japanese beetle (Popillia japonica) and to a variant of western corn rootworm (Diabrotica virgifera virgifera) resistant to crop rotation by down-regulating gene expression related to defense signaling [lipoxygenase 7 (lox7), lipoxygenase 8 (lox8), and 1-aminocyclopropane-1-carboxylate synthase (acc-s)]. The down-regulation of these genes, in turn, reduced the production of cysteine proteinase inhibitors (CystPIs), which are specific deterrents to coleopteran herbivores. Beetle herbivory increased CystPI activity to a greater degree in plants grown under ambient than under elevated CO2. Gut cysteine proteinase activity was higher in beetles consuming foliage of soybeans grown under elevated CO2 than in beetles consuming soybeans grown in ambient CO2, consistent with enhanced growth and development of these beetles on plants grown in elevated CO2. These findings suggest that predicted increases in soybean productivity under projected elevated CO2 levels may be reduced by increased susceptibility to invasive crop pests.

Emergent decision-making in biological signal transduction networks

Helikar, Tomáš; Konvalina, John; Heidel, Jack; Rogers, Jim A.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.5%
The complexity of biochemical intracellular signal transduction networks has led to speculation that the high degree of interconnectivity that exists in these networks transforms them into an information processing network. To test this hypothesis directly, a large scale model was created with the logical mechanism of each node described completely to allow simulation and dynamical analysis. Exposing the network to tens of thousands of random combinations of inputs and analyzing the combined dynamics of multiple outputs revealed a robust system capable of clustering widely varying input combinations into equivalence classes of biologically relevant cellular responses. This capability was nontrivial in that the network performed sharp, nonfuzzy classifications even in the face of added noise, a hallmark of real-world decision-making.

A thyroid hormone receptor mutation that dissociates thyroid hormone regulation of gene expression in vivo

Machado, Danielle S.; Sabet, Amin; Santiago, Leticia A.; Sidhaye, Aniket R.; Chiamolera, Maria I.; Ortiga-Carvalho, Tania M.; Wondisford, Fredric E.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.45%
Resistance to thyroid hormone (RTH) is most often due to point mutations in the β-isoform of the thyroid hormone (TH) receptor (TR-β). The majority of mutations involve the ligand-binding domain, where they block TH binding and receptor function on both stimulatory and inhibitory TH response elements. In contrast, a few mutations in the ligand-binding domain are reported to maintain TH binding and yet cause RTH in certain tissues. We introduced one such naturally occurring human RTH mutation (R429Q) into the germline of mice at the TR-β locus. R429Q knock-in (KI) mice demonstrated elevated serum TH and inappropriately normal thyroid-stimulating hormone (TSH) levels, consistent with hypothalamic–pituitary RTH. In contrast, 3 hepatic genes positively regulated by TH (Dio1, Gpd1, and Thrsp) were increased in R429Q KI animals. Mice were then rendered hypothyroid, followed by graded T3 replacement. Hypothyroid R429Q KI mice displayed elevated TSH subunit mRNA levels, and T3 treatment failed to normally suppress these levels. T3 treatment, however, stimulated pituitary Gh levels to a greater degree in R429Q KI than in control mice. Gsta, a hepatic gene negatively regulated by TH, was not suppressed in R429Q KI mice after T3 treatment...

X chromosome-wide analyses of genomic DNA methylation states and gene expression in male and female neutrophils

Yasukochi, Yukio; Maruyama, Osamu; Mahajan, Milind C.; Padden, Carolyn; Euskirchen, Ghia M.; Schulz, Vincent; Hirakawa, Hideki; Kuhara, Satoru; Pan, Xing-Hua; Newburger, Peter E.; Snyder, Michael; Weissman, Sherman M.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.45%
The DNA methylation status of human X chromosomes from male and female neutrophils was identified by high-throughput sequencing of HpaII and MspI digested fragments. In the intergenic and intragenic regions on the X chromosome, the sites outside CpG islands were heavily hypermethylated to the same degree in both genders. Nearly half of X chromosome promoters were either hypomethylated or hypermethylated in both females and males. Nearly one third of X chromosome promoters were a mixture of hypomethylated and heterogeneously methylated sites in females and were hypomethylated in males. Thus, a large fraction of genes that are silenced on the inactive X chromosome are hypomethylated in their promoter regions. These genes frequently belong to the evolutionarily younger strata of the X chromosome. The promoters that were hypomethylated at more than two sites contained most of the genes that escaped silencing on the inactive X chromosome. The overall levels of expression of X-linked genes were indistinguishable in females and males, regardless of the methylation state of the inactive X chromosome. Thus, in addition to DNA methylation, other factors are involved in the fine tuning of gene dosage compensation in neutrophils.

Universal distribution of component frequencies in biological and technological systems

Pang, Tin Yau; Maslov, Sergei
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.56%
Bacterial genomes and large-scale computer software projects both consist of a large number of components (genes or software packages) connected via a network of mutual dependencies. Components can be easily added or removed from individual systems, and their use frequencies vary over many orders of magnitude. We study this frequency distribution in genomes of ∼500 bacterial species and in over 2 million Linux computers and find that in both cases it is described by the same scale-free power-law distribution with an additional peak near the tail of the distribution corresponding to nearly universal components. We argue that the existence of a power law distribution of frequencies of components is a general property of any modular system with a multilayered dependency network. We demonstrate that the frequency of a component is positively correlated with its dependency degree given by the total number of upstream components whose operation directly or indirectly depends on the selected component. The observed frequency/dependency degree distributions are reproduced in a simple mathematically tractable model introduced and analyzed in this study.

Dissociable contribution of prefrontal and striatal dopaminergic genes to learning in economic games

Set, Eric; Saez, Ignacio; Zhu, Lusha; Houser, Daniel E.; Myung, Noah; Zhong, Songfa; Ebstein, Richard P.; Chew, Soo Hong; Hsu, Ming
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
65.55%
Game theory is used throughout the social and biological sciences to study behavior in social interactions. Recent research suggests an important role for the dopamine neurotransmitter system in these types of decisions. This study used a competitive game to study how people varied in their decision-making processes and related these differences in the set of genes that carry out biological functions required for dopaminergic functioning. We found that genes differentially expressed in separate brain regions influenced distinct components of people’s decision-making processes and that a surprising degree of consistency exists with what is known at the brain level about how people make decisions in social interactions.

Avaliação da aprendizagem no curso de licenciatura em ciências biológicas da UEG unidade Iporá: uma leitura das concepções de docentes e discentes; Evaluation of learning in the course of degree in Biological sciences UEG Iporá unit: a reading of the designs of teachers and students

SILVA, Flavia Damacena Sousa
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Educação em Ciências e Matemática; Ciências Exatas e da Terra Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Educação em Ciências e Matemática; Ciências Exatas e da Terra
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
105.64%
The main objective of this research was to analyze and understand the role of assessment of learning in the training of teachers, especially those that work in higher education in the area of teachers training. Considering the entire evaluation context with their contradictions and controversies and the different concepts I decided to study the assessment of learning process in an undergraduate course of Biological Sciences, from the State University of Goiás, Brazil. The study included teachers and students of the 2nd, 3rd and 4th grades in that course. The proposal was to investigate the documents guiding of evaluation practice of teachers and trainers, in order to grasp the concepts of teachers and academics on the assessment of learning. To develop this proposal the following research questions was formulated: What are the conceptions of learning assessment from teacher trainers and students of Biological Sciences course in this University and yet, what are the consequences of these conceptions in teachers' practice and training of undergraduates? To answer these questions was carried out a qualitative study, whose method was the case study that considers relevant to observe and understand the subjects in their context of social and historical; I was also a participating in this study since it was considered for analysis of data my own experience beyond the academic experiences lived throughout my professional practice. It was noted that scholars tend to understand the assessment...

O estágio supervisionado no curso de licenciatura em Ciências Biológicas na Universidade Federal de Goiás – Campus Goiânia; The Supervised Internship I in Biological Sciences Bachelor’s degree, at the Federal University of Goiás– Goiânia’s Campus

Souza, Leandro Nunes de
Fonte: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Educação em Ciências e Matemática (PRPG); Pró-Reitoria de Pós-graduação (PRPG) Publicador: Universidade Federal de Goiás; Brasil; UFG; Programa de Pós-graduação em Educação em Ciências e Matemática (PRPG); Pró-Reitoria de Pós-graduação (PRPG)
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
85.58%
The objective of this study is to understand how it performs Internship Required in Degree in Biological Sciencesthe Federal University of Goiás, Goiânia Campus, unveiling the different conceptions expressed in stage activities in this component. With the intention of accomplishing these purposes, we realized the need for a qualitative approach that involved, satisfactorily, all the elements of our analysis that, in fact, be understood in their complexity. From this perspective, we chose the method of case study, for which we used as a tool for data collection study document. The documents analyzed were the official documents, national and local, governing training courses for teachers of Science / Biology and Supervised, besides PPC Course investigated Plans Teaching disciplines Internship and Internship Reports. The data collected were analyzed using the technique of content analysis proposed by Bardin (2010). By analyzing the official documents we see that they they conceive stage as a moment of rapprochement with the school reality, this approach guided a link between the theory and practice, and reveal a conception of how research stage. Already the PPC treats the stage as a time of learning techniques...

Desenvolvimento e análise de software educacional alternativo ao uso de animais em aulas práticas de fisiologia : FISIOPRAT; Development and analysis of alternative educational software for use of animals in physiology¿s lab classes : FISIOPRAT

Francisco Cubo Neto
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 31/01/2011 PT
Relevância na Pesquisa
55.58%
A análise histórica do ensino de Fisiologia mostra que desde o final do século XVIII, quando começou a ser estudada, a eletrofisiologia vem sendo ensinada da mesma maneira: aplicação de estímulo químico e, em algumas vezes, elétrico em diferentes partes do corpo animal e, a seguir, discussão das respostas observadas. Por outro lado, o crescente avanço tecnológico permitiu o surgimento e a inserção de novas ferramentas educacionais, como vídeo aulas, animações e simulações computacionais, sem que houvesse prejuízo na qualidade do ensino. O objetivo dessa dissertação é desenvolver um material didático alternativo ao uso de animais no ensino de Fisiologia, recriando virtualmente a aula prática referente ao estudo dos reflexos medulares em rã. O software criado, intitulado FISIOPRAT, foi baseado no roteiro de aula prática utilizado nos cursos de Biologia, Enfermagem e Medicina da Universidade Estadual de Campinas, de modo a apresentar o mesmo conteúdo da aula tradicional. Para a avaliação da eficácia do material criado, o FISIOPRAT foi testado com alunos do terceiro ano do curso de Licenciatura em Ciências Biológicas, do segundo ano do curso de Bacharelado e Licenciatura em Ciências Biológicas, do segundo ano do curso de Medicina e do primeiro ano do curso de Bacharelado e Licenciatura em Enfermagem. Cada turma foi dividida aleatoriamente em dois grupos: o grupo controle aula prática tradicional (APT) realizou a aula prática utilizando o modelo animal e o grupo aula prática FISIOPRAT (APF) realizou a aula prática utilizando o software. Em seguida os grupos receberam o mesmo instrumento de avaliação...

Systemic Darwinism

Winther, Rasmus Grønfeldt
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
55.59%
Darwin's 19th century evolutionary theory of descent with modification through natural selection opened up a multidimensional and integrative conceptual space for biology. We explore three dimensions of this space: explanatory pattern, levels of selection, and degree of difference among units of the same type. Each dimension is defined by a respective pair of poles: law and narrative explanation, organismic and hierarchical selection, and variational and essentialist thinking. As a consequence of conceptual debates in the 20th century biological sciences, the poles of each pair came to be seen as mutually exclusive opposites. A significant amount of 21st century research focuses on systems (e.g., genomic, cellular, organismic, and ecological/global). Systemic Darwinism is emerging in this context. It follows a “compositional paradigm” according to which complex systems and their hierarchical networks of parts are the focus of biological investigation. Through the investigation of systems, Systemic Darwinism promises to reintegrate each dimension of Darwin's original logical space. Moreover, this ideally and potentially unified theory of biological ontology coordinates and integrates a plurality of mathematical biological theories (e.g....

Earliest evidence of modern human life history in North African early Homo sapiens

Smith, Tanya M.; Tafforeau, Paul; Reid, Donald J.; Grün, Rainer; Eggins, Stephen; Boutakiout, Mohamed; Hublin, Jean-Jacques
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
55.56%
Recent developmental studies demonstrate that early fossil hominins possessed shorter growth periods than living humans, implying disparate life histories. Analyses of incremental features in teeth provide an accurate means of assessing the age at death of developing dentitions, facilitating direct comparisons with fossil and modern humans. It is currently unknown when and where the prolonged modern human developmental condition originated. Here, an application of x-ray synchrotron microtomography reveals that an early Homo sapiens juvenile from Morocco dated at 160,000 years before present displays an equivalent degree of tooth development to modern European children at the same age. Crown formation times in the juvenile's macrodont dentition are higher than modern human mean values, whereas root development is accelerated relative to modern humans but is less than living apes and some fossil hominins. The juvenile from Jebel Irhoud is currently the oldest-known member of Homo with a developmental pattern (degree of eruption, developmental stage, and crown formation time) that is more similar to modern H. sapiens than to earlier members of Homo. This study also underscores the continuing importance of North Africa for understanding the origins of human anatomical and behavioral modernity. Corresponding biological and cultural changes may have appeared relatively late in the course of human evolution.

In The Spotlight: Class of 2006 Honors

Usher, David
Fonte: University of Delaware Department of Biological Sciences Publicador: University of Delaware Department of Biological Sciences
Tipo: Outros Formato: 104546 bytes; application/pdf
EN_US
Relevância na Pesquisa
55.57%
A brief look at the Class of 2006 graduates earning an Honors Degree with Distinction or a Degree with Distinction from the Department of Biological Sciences.

In The Spotlight: Class of 2007 Honors

Usher, David
Fonte: University of Delaware Department of Biological Sciences Publicador: University of Delaware Department of Biological Sciences
Tipo: Outros
EN_US
Relevância na Pesquisa
55.57%
A brief look at the Class of 2007 graduates earning an Honors Degree with Distinction or a Degree with Distinction from the Department of Biological Sciences.

In The Spotlight: Class of 2004 Honors

Usher, David
Fonte: University of Delaware Department of Biological Sciences Publicador: University of Delaware Department of Biological Sciences
Tipo: Outros Formato: 112875 bytes; application/pdf
EN_US
Relevância na Pesquisa
55.57%
A brief look at the Class of 2004 graduates earning an Honors Degree with Distinction or a Degree with Distinction from the Department of Biological Sciences.

In The Spotlight: Class of 2005 Honors

Usher, David
Fonte: University of Delaware Department of Biological Sciences Publicador: University of Delaware Department of Biological Sciences
Tipo: Outros Formato: 121919 bytes; application/pdf
EN_US
Relevância na Pesquisa
55.57%
A brief look at the Class of 2005 graduates earning an Honors Degree with Distinction or a Degree with Distinction from the Department of Biological Sciences.