49 resultados para Craft specialization


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Two common South American species of lynx spiders, Peucetia rubrolineata and P. flava (Oxyopidae), were surveyed on three localities in southeastern Brazil to determine plant choice. Both species were found to be associated with plants bearing glandular trichomes. A literature review and complementary data show that ten Peucetia species are associated with up to 55 plant species bearing glandular trichomes in at least 20 distinct vegetation types (phytophysiognomies) in more than 36 localities in the Neotropical, Neartic, Afrotropical, and Paleartic regions. The main plant families used by the spiders were Solanaceae, Asteraceae, and Melastomataceae. The specialization of the Peucetia species for plants bearing glandular trichomes may have evolved because insects adhered to these sticky structures may be used as prey by the spiders.

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Epiphytes constitute a great part of the vegetation biomass in Neotropical forests, offering a large variety of resources to birds. Despite their structural and ecological importance, few studies investigated the use of epiphytes by birds in the Neotropical region. We studied the bird species that exploit vascular epiphytes (and hemi-epiphytes) in an Atlantic forest site in southeastern Brazil. The resources exploited, seasonal variation in the use of epiphytes, the frequency of foraging and selectivity in epiphytes, and the relationship between the use of epiphytes and the participation in mixed-species bird flocks were investigated. After 360 h of observations along trails crossing the forest, 24 bird species (12 families) were recorded in a total of 74 events of epiphyte exploitation. Thamnophilidae (four species), Trochiliclae, Thraupidae and Furnariidae (three species) were the richest bird families in our sample, while Furnariidae and Dendrocolaptidae were the more frequently recorded families. Plants in the Bromeliaceae and Araceae families were the most abundant and more frequently exploited epiphytes. Nectar, water, nest material and invertebrates were the most frequently exploited resources, mainly from Bromeliaceae. None of the species for which we had enough data revealed to be a frequent user of epiphytes for foraging or selective to any epiphyte group. The White-eyed Foliage-gleaner (Automolus leucophthalmus; Furnariidae), a common participant of understory mixed-species flocks, exploited epiphytes more frequently when associated with mixed-species flocks. The utilization of epiphytes was opportunistic for most of the bird species recorded and occurred throughout the year with no seasonal variation.

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We describe a new species of hylid frog, Scinax peixotoi, from Queimada Grande Island, southeastern Brazil. The new species belongs to the Scinax perpusillus species group, in which all known forms inhabit bromeliads, and is diagnosed by the following set of characters: moderate-size (males 18.8-20.7 mm SVL, females 22.4-25.1 mm SVL); canthus rostralis distinct; dorsal skin slightly rugose; and a distinct advertisement call with relatively low dominant frequency. The new species is known from a single population on Queimada Grande, an island of 43 ha, approximately 33 km distant from the coast of São Paulo State, where it inhabits scattered patches of bromeliads. The highly specialized and patchy habitat of S. peixotoi, associated with its small range size, make this species highly susceptible to stochastic or anthropogenic habitat disturbances, which could lead it to extinction. Copyright © 2007 Magnolia Press.

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The suprachiasmatic nucleus, an essential diencephalic component of the circadian timing system, plays a role in the generation and modulation of behavioral and neuroendocrine rhythms in mammals. Its cytoarchitecture, neurochemical and hodological characteristics have been investigated in various mammalian species, particularly in rodents. In most species, two subdivisions, based on these aspects and considered to reflect functional specialization within the nucleus, can be recognized. Many studies reveal a typical dense innervation by serotonergic fibers in this nucleus, mainly in the ventromedial area, overlapping the retinal afferents. However, a different pattern occurs in certain animals, which lead us to investigate the distribution of serotonergic afferents in the suprachiasmatic nucleus of the Capuchin monkey, Cebus apella, compared to the marmoset, Callithrix jacchus, and two Rattus norvegicus lines (Long Evans and Wistar), and to reported findings for other mammalian species. Our morphometric data show the volume and length of the suprachiasmatic nucleus along the rostrocaudal axis to be greatest in C. apella > C. jacchus > Long Evans ≥ Wistar rats, in agreement with their body sizes. In C. apella, however, the serotonergic terminals occupy only some 10% of the nucleus' area, less than the 25% seen in the marmoset and rats. The distribution of the serotonergic fibers in C. apella does not follow the characteristic ventral organization pattern seen in the rodents. These findings raise questions concerning the intrinsic organization of the nucleus, as well as regarding the functional relationship between serotonergic input and retinal afferents in this diurnal species. © 2007 Elsevier B.V. All rights reserved.

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Professional-patient relationship and its importance for a good performance and success of the dental treatment must be reflected upon by means of their bioethical aspects. Our study aimed at evaluating dentist-surgeons' knowledge (n=163) in conducting specialization courses at São Paulo State University-UNESP, on these aspects. Out of the people surveyed, 88.1% mentioned that a decision for the treatment should be made by mutual agreement between professionals and patients, however, 26.4% report that patients' or their legal representative's participation in decision-making can cause negative interference. Professionals' acting when patients choose a less suitable treatment, 95.6% try to convince patients that it is not the best choice and persuade them for a better one by keeping the paternalistic model. It was noticed that 20.3% did not know how to relate the importance of professional-patient interaction as regards the dental treatment. It was therefore concluded that many dentist-surgeons are not taking these bioethical aspects into account in clinical practice.

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The tongue of domestic animals varies in size and shape and according to these animals feeding habits, there are different degrees of tongue surface specialization. At the dorsal surface of the tongue lingual papillae can be observed, such as the vallate papillae, related to taste perception. With the help of a magnifying glass, differences in the number, size and distribution of vallate papillae were studied. Fifty five tongues of adult domestic cats from both sexes (38 females and 17 males) were analyzed. The samples were fixed in 10% buffered formalin. The vallate papillae were found to be symmetrically distributed on 21 tongues (38.18%). However, it was observed that in some of the tongues the number of vallate papillae varied when one side of the tongue was compared to its contralateral side. The vallate papillae showed different shapes: elongated (42.58%), oval (31.61%), round (25.48%) and pear shaped (0.33%). The vallate papillae were classified into 10 different categories: symmetrical I (2 right and 2 left), II (3:3), III (4:4) and asymmetrical IV (3:2), V (4:2), VI (2:3), VII (4:3), VIII (5:3), IX (3:4) and X (4:5). Measurements of length and width were made with averages of 0.84 ± 0.23 mm and 0.55 ± 0.18 mm, respectively, besides the calculation of the total area of these papillae per tongue, that showed average of 2,74 ± 0,31 mm 2 in males and 1,94 ± 0,14 mm 2 in females However, upon examining the lingual papillae of the cat tongues, specimens demonstrating 7, 8 or 9 vallate papillae, arranged in pairs (4:3, 5:3, 3:4 and 4:5) by category, were observed in this study but not cited in the literature.

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Similar to mammals, in fish the cellular interactions between Sertoli cells (SC) and germ cells (GC) in the seminiferous epithelium have important structural and functional roles. In this review, we give a brief summary of these interactions, in particular those on the cell junctions. Despite the scarcity of detailed empirical data, it appears that both basic types of adhesive junctions (actin- and intermediate filaments-related) are present between SC. However, the actin-related multifunctional junction known as the ectoplasmic specialization is seemingly present only in some cartilaginous fish. Conversely, SC in other fish species are joined by actin-related junctions similar to typical zonulae or puncta adherens found in other epithelia. Adhesive junctions are also found between SC and GC and between GC and GC, and due to their particular characteristics these junctions are known as desmosome-like junctions. In terms of intercellular communication, connexins and gap junctions have been shown to occur between SC in fish, and they may be involved in the coordination of the synchronous development of GC within the cysts. It is also possible that gap junctions may form an interconnected network between SC and GC within a cyst. Concerning the SC barrier, tight junctions between fish SC apparently form a functional barrier only in cysts containing haploid GC, and different from mammals, meiotic GC in fish are not shielded from the vascular system. In summary, although still not well investigated, cell-cell interactions in the seminiferous epithelium of fish seem to be crucial for GC development, and their disturbance, for example by changing environmental conditions, will probably affect GC survival and fertility. © Springer Science+Business Media B.V. 2008.

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The objective of this study was to evaluate: the profile of the surgeon-dentist that undergoes a course in specialization at the Odontology Faculty of Aracatuba/UNESP, Brazil; if they requested informed consent from the patient and/or their legal representative before the realization of procedures, and if the treatment was decided upon with the patient. It was elaborated, validated and applied in questionnaire form, and the data obtained was analyzed by the program EPI-INFO 3.3 The conclusion was, given that surgeon-dentists still do not obtain any type of document before beginning treatment, a large percentage of them are totally vulnerable if submitted to ethical or legal prosecution and that it is necessary to be aware of this aspect.

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This paper attempts to assess both the touristic potential of scenic attractions and the environmental impacts resulting from the public use of such attractions in the Rifaina Municipality, State of São Paulo, Southeastern Brazil. In the recent past, this municipality had its economy concentrated in rural activities (livestock, corn, rice and bean crops) and in the ceramic industry (production of bricks, tiles and shackles),which was largely developed in the floodplain of the Rio Grande before the construction of the Jaguara Power Plant Dam. The impacts resulting from touristic activities were evaluated by applying the VIM - Visitor Impact Management method, with emphasis on biophysical indicators. The main touristic attractions analyzed were: (1) Rifaina artificial beach; (2) Jaguara Reservoir; (3) Morro do Chapéu (scenic hill); (4) Touristic railroad; and (5) Cuestas cliffs. Attractions (1) and (2) are the most exploited ones, including, in the second case, nautical sports, sportive and craft fishing, and summer lodging. Although currently disabled, the touristic railroad presents potential conditions to be re-explored. Attractions (3) and (5), despite keeping high landscape and ecological ecotouristic potential, are the least visited places. In the present paper, a preliminary characterization of the major issues of tourism industry in the Rifaina municipality is made, including suggestions for the sustainable exploitation of tourism resources. The final results of the environmental impact evaluation of the tourism activities include small impacts in attractions (4) and (5) and moderate impacts to the three first attractions. In order to keep the sustainable touristic potential for that municipality this study proposes the improvement of the following measures: to foster research projects on technical or scientific aspects of the touristic attractions, improvement of tourism infrastructure and the creation of an Environmental Protection Area (APA) of the cuestas' scarps.

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Excessive specialization and the fascinating advances of technology and the sciences, particularly of mathematics, cause a false dichotomy between the sciences and technology and the arts and humanities. The survival of civilization is threatened. Clearly, the fragility of the current social organization allows for the exclusion of the larger part of the population from the benefits of progress. We need to revert this scenario, moving into a civilization without inequity, without uncontrolled consumerism and with respect for social and environmental conditions. In this paper, we discuss these issues and we illustrate with some examples how this can be achieved. We discuss the development of mathematics in Brazil, environmental crimes and its prevention through mathematical education, and a proposal for alternative educational models, using as an example the Waldorf Educational System.

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Seedling morphology is relevant in classification, taxonomy, and vegetation studies to understand plant life cycles, germination succession and requirements, and developmental progression. However, most morphological studies of seedlings lack analysis of organ anatomy, impeding the comprehension of series of development and establishment in a particular environment. Here, we have taken a traditional anatomical approach to examine the stages of seedling development in Epiphyllum phyllanthus, a holo-epiphytic cactus of tribe Hylocereeae. The goals were 1) to offer a comprehensive description of growth series in E. phyllanthus seedlings based on morphological and anatomical analysis and 2) to examine the initial growth phases in the life cycle of this species to identify organ development and understand their adaptive significance in relation to seedling establishment. Our results include descriptions of seed morphology, embryonic features, and seedling vascularization pattern in the root, hypocotyl, cotyledons, and epicotyl. The morphological and developmental patterns in E. phyllanthus seedlings have potential phylogenetic and ontogenetic implications in the Cactaceae. Characters such as the presence of mucilage on the seed coat, the lack of seed operculum, and large cotyledons in E. phyllanthus are comparable to basal cacti, but the root anatomy is more similar to columnar relatives. At the familial level, there is an apparent trend in decreasing number of phloem and xylem poles in the stele of primary root, correlated with degree of specialization and advanced phylogenetic position: tetrarch to septarch-octarch in basal lineages, tetrarch Cereus-type in columnar species, to the diarch vascular system in Rhipsalideae and some species with cylindric/globose stem. © Torrey Botanical Club.

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Within the proposed framework for this issue of the journal História da Historiografia, the present article is a concise report on the trajectory of a university professor of history. The author writes on the obtainment of his degree at the USP, his participation in the beginning of undergraduate and graduate courses in the interior of the state of São Paulo, including the experience of taking part in the beginnings of the public university Universidade Estadual Paulista (UNESP). The author also discusses aspects of his academic and institutional life, and reports on the process of his insertion in an established historiographical line of work. It can be introductorily noted that the reader will not always find a linear chronological order, due to the multifaceted nature of the activities of a university professor of history. An additional note is that I have not made complete bibliographical citations, as I understand that the readers are specialists in the historians' craft.

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Mistletoes represent the best example of specialization in seed dispersal, with a reduced assemblage of dispersal agents. Specific dispersal requirements mediated by the specificity of seed deposition site have apparently led to the evolution of such close relationships between mistletoes and certain frugivores. Here, we provide evidences for another case of specialization involving epiphytic cacti in the genus Rhipsalis, and small Neotropical passerines Euphonia spp., which also act as the main seed dispersers of mistletoes in the family Viscaceae. With field observations, literature search, and observations on captive birds, we demonstrated that Rhipsalis have specific establishment requirements, and euphonias are the most effective dispersers of Rhipsalis seeds in both quantitative and qualitative aspects, potentially depositing seeds onto branches of host plants. We interpret the similar dispersal systems of Rhipsalis and Viscaceae mistletoes, which involve the same dispersal agents, similar fruit morphologies, and fruit chemistry as convergent adaptive strategies that enable seeds of both groups to reach adequate microsites for establishment in host branches. © 2013 by The Association for Tropical Biology and Conservation.

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In Epiponini division of labor is associated with age polyethism and individual task specialization. We observed worker activities in three colonies of Metapoybia miltoni in Brazil. We analyzed differences of task allocation among age groups. Old workers tend to forage more than young, but age polyethism was less evident in other tasks. Age composition of population could be a determinant factor in task allocation. Workers are probably allocating to perform tasks according to colony needs, and not to individual's age. Considering age population in studies of division of labor could help to understand how colonies respond to different situations.