33 research outputs found

    Technical and economic efficiency of bovine weighing methods

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    The objective of this study was to evaluate the technical and economic efficiency of different methods of cattle weighing, and to develop mathematical equations to estimate the breakeven point for the adoption of electronic weighing, i.e., to estimate how many animals are required for the acquisition and use of an electronic scale to be economically viable. The survey was conducted in confined beef cattle, from the Federal Institute of Education, Science and Technology in the south of Minas Gerais, IFSUL DE MINAS, Muzambinho Campus, from July to December 2014. Two methods of weighing cattle were evaluated: an electronic scale and a tape measure, using a barimetric tape for dairy cattle and a barimetric tape for beef cattle, and a conventional tape measure involving the conversion of centimeters into body weight using a specific table. Thirty-three animals identified with plastic ear tags were weighed using each method. Animals of the Nellore, Senepol, Girolando, and Red-angus breeds, aged 0–1, 1–2, and 2–3 years, were weighed 402 times in total. The time taken to weigh animals with the electronic scale was the lowest, followed by that with the barimetric tape, and that with conventional tape measure with conversion. The electronic scale exhibited the greatest technical efficiency, owing to the lack of error and the lowest time required to weigh animals. However, the costs associated with the use of this equipment were the highest, which depended on the purchasing cost. The mathematical equations developed will help technicians and cattle farmers to rapidly and precisely estimate the minimum number of animals that should compose a production system to ensure economic viability for the adoption of an electronic method to weigh cattle

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    The occipital lobe convexity sulci and gyri

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    INTRODUÇÃO: A anatomia da face súpero-lateral do lobo occipital é tão complexa e variável que a sua descrição precisa não é encontrada nos livros clássicos de anatomia. Os sulcos e giros occipitais da convexidade cerebral encontram-se descritos com nomenclaturas diferentes de acordo com os diversos autores. O objetivo deste estudo foi investigar e descrever a anatomia da face súpero-lateral lobo occipital e esclarecer a sua nomenclatura. MÉTODOS: As configurações anatômicas dos sulcos e giros na face súpero-lateral do lobo occipital de 20 hemisférios cerebrais foram examinados a fim de identificar os padrões mais característicos e consistentes. RESULTADOS: Os sulcos occipitais mais característicos e consistentes identificados neste estudo foram o sulco intraoccipital, o sulco occipital transverso e o sulco occipital lateral. A morfologia da junção do sulco occipital transverso com o sulco intraoccipital foi identificada como sendo o aspecto mais importante para definir o padrão de giros cerebrais da face súperolateral do lobo occipital. CONCLUSÕES: O conhecimento das principais características dos sulcos e giros occipitais permite o reconhecimento de uma configuração básica do lobo occipital e a identificação de suas principais variações anatômicasBACKGROUND: The anatomy of the occipital lobe convexity is so intricate and variable that its precise description is not found in the classic anatomy textbooks, and the occipital sulci and gyri are described with different nomenclatures according to different authors. The aim of this study was to investigate and describe the anatomy of the occipital lobe convexity and clarify its nomenclature. METHODS: The configurations of sulci and gyri on the lateral surface of the occipital lobe of 20 cerebral hemispheres were examined in order to identify the most characteristic and consistent patterns. RESULTS: The most characteristic and consistent occipital sulci identified in this study were the intraoccipital, transverse occipital, and lateral occipital sulci. The morphology of the transverse occipital sulcus and the intraoccipital sulcus connection was identified as the most important aspect to define the gyral pattern of the occipital lobe convexity. CONCLUSIONS: Knowledge of the main features of the occipital sulci and gyri permits the recognition of a basic configuration of the occipital lobe and the identification of its sulcal and gyral variation

    Microsurgical Anatomy of the Optic Radiation and Related Fibers in 3-Dimensional Images

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    BACKGROUND: The fiber dissection technique provides unique 3-dimensional anatomic knowledge of the white matter. OBJECTIVE: To examine the optic radiation anatomy and its important relationship with the temporal stem and to discuss its findings in relation to the approaches to temporal lobe lesions. METHODS: We studied 40 cerebral hemispheres of 20 brains that had been fixed in formalin solution for 40 days. After removal of the arachnoid membrane, the hemispheres were frozen, and the Klingler technique was used for dissection under magnification. Stereoscopic 3-dimensional images of the dissection were obtained for illustration. RESULTS: The optic radiations are located deep within the superior and middle temporal gyri, always above the inferior temporal sulcus. The mean distance between the cortical surface and the lateral edge of the optic radiation was 21 mm. Its fibers are divided into 3 bundles after their origin. The mean distance between the anterior tip of the temporal horn and the Meyer loop was 4.5 mm, between the temporal pole and the anterior border of the Meyer loop was 28.4 mm, and between the limen insulae and the Meyer loop was 10.7 mm. The mean distance between the lateral geniculate body and the lateral margin of the central bundle of the optic radiation was 17.4 mm. CONCLUSION: The white matter fiber dissection reveals the tridimensional intrinsic architecture of the brain, and its knowledge regarding the temporal lobe is particularly important for the neurosurgeon, mostly because of the complexity of the optic radiation and related fibers.7116017

    Microsurgical Anatomy of the Optic Radiation and Related Fibers in 3-Dimensional Images

    No full text
    BACKGROUND: The fiber dissection technique provides unique 3-dimensional anatomic knowledge of the white matter. OBJECTIVE: To examine the optic radiation anatomy and its important relationship with the temporal stem and to discuss its findings in relation to the approaches to temporal lobe lesions. METHODS: We studied 40 cerebral hemispheres of 20 brains that had been fixed in formalin solution for 40 days. After removal of the arachnoid membrane, the hemispheres were frozen, and the Klingler technique was used for dissection under magnification. Stereoscopic 3-dimensional images of the dissection were obtained for illustration. RESULTS: The optic radiations are located deep within the superior and middle temporal gyri, always above the inferior temporal sulcus. The mean distance between the cortical surface and the lateral edge of the optic radiation was 21 mm. Its fibers are divided into 3 bundles after their origin. The mean distance between the anterior tip of the temporal horn and the Meyer loop was 4.5 mm, between the temporal pole and the anterior border of the Meyer loop was 28.4 mm, and between the limen insulae and the Meyer loop was 10.7 mm. The mean distance between the lateral geniculate body and the lateral margin of the central bundle of the optic radiation was 17.4 mm. CONCLUSION: The white matter fiber dissection reveals the tridimensional intrinsic architecture of the brain, and its knowledge regarding the temporal lobe is particularly important for the neurosurgeon, mostly because of the complexity of the optic radiation and related fibers

    Strategies to select yeast starter cultures for production of flavour compounds in cachaça fermentations.

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    In this work, we have used classical genetics techniques to find improved starter strains to produce cachac¸a with superior sensorial quality. Our strategy included the selection of yeast strains resistant to 5,50,500-trifluor-D,L-leucine (TLF) and cerulenin, since these strains produce higher levels of higher alcohols and esters than parental strains. However, no clear relationship was observed when levels of flavoring compounds were compared with the levels expression of the genes (BAT1, BAT2, ATF2, EEB1 genes) involved with the biosynthesis of flavoring compounds. Furthermore, we determined the stability of phenotypes considered as the best indicators of the quality of the cachac¸a for a parental strain and its segregants. By applying the principal component analysis, a cluster of segregants, showing a high number of characteristics similar to the parental strain, was recognized. One segregant, that was resistant to TLF and cerulenin, also showed growth stability after six consecutive replications on plates containing high concentrations of sugar and ethanol. ‘‘Cachac¸a’’ produced at laboratory scale using a parental strain and this segregant showed a higher level of flavoring compounds. Both strains predominated in an open fermentative process through seven cycles, as was shown by mitochondrial restriction fragment length polymorphisms analysis. Based on the physical chemical composition of the obtained products, the results demonstrate the usefulness of the developed strategies for the selection of yeast strains to be used as starters in ‘‘cachac¸a’’ production
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