3,740 research outputs found

    DIEstro: Motion sensor platform for cattle oestrus detection

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    The reproductive efficiency of dairy industry has decreased over the last ten years due mainly to an intensification of the management techniques of the herd, and an increase of total number of animals. A main objective of worldwide dairy farms is to ensure that dairy cows, produce as much milk as possible. A cow produces milk while it has a calf to breastfeed, therefore, the less time passes between births, the more ”productive” the cows are. This is the principal reason why the precise heat (oestrus) detection has became so important, a task traditionally assigned to veterinary and expert people examining and watching the cattle behavior, and in recent years to electronic devices monitoring the cow’s physical activity. Tracking the animal’s physical activity by means of a portable device strapped to each animal, is known to be a very effective way to determine heat, but sometimes requires expensive hardware and large batteries. In this work, a low-cost micropower wireless system able to automatically detect oestrus period of cattle is presented. It was designed in cooperation with BQN, a company developing technology for the agribusiness industry in Uruguay. The tracker seizes the recent availability of 1 uA micropower accelerometers, LoRa long range transceivers, and FRAM microcontrollers, to achieve a coin cell battery powered paradigm for oestrus detection. The device records 3 axis acceleration information, process it, and periodically sends it to a server; it has a measured ultra low power consumption of 4 uA while collecting/processing data, reaching a very large (> 10km) communication distance using a star topology and LoRa technology at countryside areas. The scope of the project and this documentation is the entire hardware and firmware development, from the start idea, design and final implementation.Agencia Nacional de Investigación e Innovació

    DIEstro: Motion sensor platform for cattle oestrus detection

    Get PDF
    The reproductive efficiency of dairy industry has decreased over the last ten years due mainly to an intensification of the management techniques of the herd, and an increase of total number of animals. A main objective of worldwide dairy farms is to ensure that dairy cows, produce as much milk as possible. A cow produces milk while it has a calf to breastfeed, therefore, the less time passes between births, the more ”productive” the cows are. This is the principal reason why the precise heat (oestrus) detection has became so important, a task traditionally assigned to veterinary and expert people examining and watching the cattle behavior, and in recent years to electronic devices monitoring the cow’s physical activity. Tracking the animal’s physical activity by means of a portable device strapped to each animal, is known to be a very effective way to determine heat, but sometimes requires expensive hardware and large batteries. In this work, a low-cost micropower wireless system able to automatically detect oestrus period of cattle is presented. It was designed in cooperation with BQN, a company developing technology for the agribusiness industry in Uruguay. The tracker seizes the recent availability of 1 uA micropower accelerometers, LoRa long range transceivers, and FRAM microcontrollers, to achieve a coin cell battery powered paradigm for oestrus detection. The device records 3 axis acceleration information, process it, and periodically sends it to a server; it has a measured ultra low power consumption of 4 uA while collecting/processing data, reaching a very large (> 10km) communication distance using a star topology and LoRa technology at countryside areas. The scope of the project and this documentation is the entire hardware and firmware development, from the start idea, design and final implementation.Agencia Nacional de Investigación e Innovació

    The influence of self-concept on school adjustment: of what concern is it to the counsellors?

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    This correlational study investigated the relationship between self-concept and school adjustment using a sample of 610 students drawn from a population of 1983 senior secondary school (two) students from Nembe town of Bayelsa State, Nigeria. Two research questions and two hypotheses were designed to guide the study. The hypotheses were tested at probability level of 0.05. The instrument for data collection was Self-concept and School Adjustment Scale. It was validated by the assistance of two experts in Measurement and Evaluation and possessed sufficient reliability indices to be used in the study. The data generated from the instrument were analyzed using SPSS (version 21). The results of the study showed that social self-concept and academic self-concept had high positive joint influence on school adjustment of secondary school students; the joint influence of self-concept on school adjustment is significant at 0.05 level of probability; social self-concept and academic self-concept each has a high positive and significant individual influence on the school adjustment of the students. Based on these findings, the conclusion drawn was that social self-concept and academic self-concept had joint and separate significant relationships with school adjustment of secondary school students in Nembe town. The counsellors should concern themselves on how to make the students believe in themselves; they should not be afraid of any subjects or tasks and that they can surmount any academic or life challenges by putting in adequate effort.KEYWORDS: Social self-concept, academic self-concept, school adjustment, confidence, success, failure

    SenE

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    SenE Written by: Hilaria Cruz & Mary Griffin Illustrated by: Matheus Bruno Neveshttps://ir.library.louisville.edu/chatino/1003/thumbnail.jp

    Biofuels, greenhouse gases and climate change. A review

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    International audienceBiofuels are fuels produced from biomass, mostly in liquid form, within a time frame sufficiently short to consider that their feedstock (biomass) can be renewed, contrarily to fossil fuels. This paper reviews the current and future biofuel technologies, and their development impacts (including on the climate) within given policy and economic frameworks. Current technologies make it possible to provide first generation biodiesel, ethanol or biogas to the transport sector to be blended with fossil fuels. Still under-development 2nd generation biofuels from lignocellulose should be available on the market by 2020. Research is active on the improvement of their conversion efficiency. A ten-fold increase compared with current cost-effective capacities would make them highly competitive. Within bioenergy policies, emphasis has been put on biofuels for transportation as this sector is fast-growing and represents a major source of anthropogenic greenhouse gas emissions. Compared with fossil fuels, biofuel combustion can emit less greenhouse gases throughout their life cycle, considering that part of the emitted CO2 returns to the atmosphere where it was fixed from by photosynthesis in the first place. Life cycle assessment (LCA) is commonly used to assess the potential environmental impacts of biofuel chains, notably the impact on global warming. This tool, whose holistic nature is fundamental to avoid pollution trade-offs, is a standardised methodology that should make comparisons between biofuel and fossil fuel chains objective and thorough. However, it is a complex and time-consuming process, which requires lots of data, and whose methodology is still lacking harmonisation. Hence the life-cycle performances of biofuel chains vary widely in the literature. Furthermore, LCA is a site- and timeindependent tool that cannot take into account the spatial and temporal dimensions of emissions, and can hardly serve as a decision-making tool either at local or regional levels. Focusing on greenhouse gases, emission factors used in LCAs give a rough estimate of the potential average emissions on a national level. However, they do not take into account the types of crop, soil or management practices, for instance. Modelling the impact of local factors on the determinism of greenhouse gas emissions can provide better estimates for LCA on the local level, which would be the relevant scale and degree of reliability for decision-making purposes. Nevertheless, a deeper understanding of the processes involved, most notably N2O emissions, is still needed to definitely improve the accuracy of LCA. Perennial crops are a promising option for biofuels, due to their rapid and efficient use of nitrogen, and their limited farming operations. However, the main overall limiting factor to biofuel development will ultimately be land availability. Given the available land areas, population growth rate and consumption behaviours, it would be possible to reach by 2030 a global 10% biofuel share in the transport sector, contributing to lower global greenhouse gas emissions by up to 1 GtCO2 eq.year−1 (IEA, 2006), provided that harmonised policies ensure that sustainability criteria for the production systems are respected worldwide. Furthermore, policies should also be more integrative across sectors, so that changes in energy efficiency, the automotive sector and global consumption patterns converge towards drastic reduction of the pressure on resources. Indeed, neither biofuels nor other energy source or carriers are likely to mitigate the impacts of anthropogenic pressure on resources in a range that would compensate for this pressure growth. Hence, the first step is to reduce this pressure by starting from the variable that drives it up, i.e. anthropic consumptions

    Using a crop model to account for the effects of local factors on the LCA of sugar beet ethanol in Picardy region, France

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    CT1 ; CT3 ; EnjS1 ; EnjS4 ; Base de données AgroclimInternational audienceThe results of published Life Cycle Assessments (LCAs) of biofuels are characterized by a large variability, arising from the diversity of both biofuel chains and the methodologies used to estimate inventory data. Here, we suggest that the best option to maximize the accuracy of biofuel LCA is to produce local results taking into account the local soil, climatic and agricultural management factors. Methods We focused on a case study involving the production of first-generation ethanol from sugar beet in the Picardy region in Northern France. To account for local factors, we first defined three climatic patterns according to rainfall from a 20-year series of weather data. We subsequently defined two crop rotations with sugar beet as a break crop, corresponding to current practice and an optimized management scenario, respectively. The six combinations of climate types and rotations were run with the process-based model CERES-EGC to estimate crop yields and environmental emissions. We completed the data inventory and compiled the impact assessments using Simapro v.7.1 and Ecoinvent database v2.0. Results Overall, sugar beet ethanol had lower impacts than gasoline for the abiotic depletion, global warming, ozone layer depletion and photochemical oxidation categories. In particular, it emitted between 28 % and 42 % less greenhouse gases than gasoline. Conversely, sugar beet ethanol had higher impacts than gasoline for acidification and eutrophication due to losses of reactive nitrogen in the arable field. Thus, LCA results were highly sensitive to changes in local conditions and management factors. As a result, an average impact figures for a given biofuel chain at regional or national scales may only be indicative within a large uncertainty band. Conclusions Although the crop model made it possible to take local factors into account in the life-cycle inventory, best management practices that achieved high yields while reducing environmental impacts could not be identified. Further modelling developments are necessary to better account for the effects of management practices, in particular regarding the benefits of fertiliser incorporation into the topsoil in terms of nitrogen losses abatement. Supplementary data and modelling developments also are needed to better estimate the emissions of pesticides and heavy metals in the field

    Long-term impact of no tillage in two intensified crop rotations on different soil organic matter fractions in Argentine Rolling Pampa

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    It is expected that the agricultural intensification occurred in recent decades in the Argentine Rolling Pampa significantly alters the SOM reserves. Therefore, it is necessary to identify soil organic carbon (C) and nitrogen (N) fractions to understand the functionality and stabilization of these reserves. Our objectives were to study the NT effect in two crop rotations, corn-double cropped wheat/soybean (MWS) and double cropped wheat/soybean (WS) on: 1) SOM and its particle size and biological fractions contents, 2) C and N stubble biomass and 3) some soil properties in order to explain the SOM differences found. The larger biomass residue remaining on the soil surface under NT promoted higher aggregate stability and lower soil temperature and pH. At 0-5 cm soil depth, NT exhibited higher C and N contents, for both uncomplexed and intimately associated to the mineral components fractions. However, the results indicated variations in the SOM protection according to the rotation: in MWS the high aggregate stability showed better physical protection, while in WS the greater cation exchange capacity and the lower value of N released by anaerobic incubation would indicate the presence of transformed SOM. At 5-20 cm soil depth, only in WS, C microbial biomass was higher with a low metabolic rate, indicating again the presence of highly decomposed SOM. The results obtained in WS under NT would indicate the possibility of achieving slower recycled of the SOM.Fil: Irizar, Alicia Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Andriulo, Adrian Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Mary, Bruno. Institut National de la Recherche Agronomique; Franci

    Mudanças na matéria orgânica edafica sob diferentes manejos de solo na província de misiones (Argentina)

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    Os solos altamente intemperizados dos trópicos perdem rapidamente matéria orgânica do solo (SOM) e podem ser afetados pela erosão hídrica e compactação depois de seu deflorestamento e agricultura contínua. O objetivo foi determinar a dinâmica da matéria orgânica do solo com capim-elefante (Pennisetum purpureum L.) em um Kandihumult da província de Misiones (Argentina) após desmatamento e cultivo contínuo de erva-mate (Ilex paraguaiensis Saint Hil.), utilizando a metodologia da abundância natural em carbono 13 (13C) e um modelo descritivo. O estudo foi conduzido em três parcelas contíguas de 50 x 100 m. As situações comparadas foram: (a) floresta nativa, e (b) local com 50 anos de monocultivo intensivo de erva- mate, e (c) erva-mate associada com capim-elefante como cultivo de cobertura sob plantio direto. Determinaram-se os conteúdos de carbono (C), de nitrogênio (N) e de 13C e a densidade aparente do solo (camadas 0 - 0,05 e 0.05 - 0,15 m) e a biomassa da gramínea. Depois de 50 anos de monocultivo de erva-mate, os conteúdos de C e N e a porosidade da camada 0 - 0,15 m da floresta nativa diminuíram em 42, 47 e 23%, respectivamente. Depois de 10 anos de associação erva-mate - capim-elefante, os conteúdos de C e N do solo e na mesma profundidade aumentaram em relação ao monocultivo de erva-mate em 19 e 12%, respectivamente, mas a porosidade não foi modificada. O aporte de C, o 13C e o C orgânico total do solo foram incorporados em um modelo de três compartimentos para avaliar a dinâmica do C proveniente do capim-elefante. A metodologia da abundância natural em 13C permitiu traçar a incorporação do C proveniente do capim-elefante e a perda do C "velho" no solo, e determinar sem ambigüidade os parâmetros do modelo: coeficiente de humificação (k1), coeficiente de mineralização da fração ativa de C (k) e o C estável (Cs). Os altos valores de k1 e k preditos pelo modelo foram atribuídos à alta contribuição do sistema radicular do capim-elefante sob plantio direto e ao clima subtropical úmido, respectivamente. No solo sob monocultivo de erva-mate, Cs representou 91% do C orgânico total do solo.Highly weathered tropical soils rapidly loose soil organic matter (SOM) and may be affected by water erosion and soil compaction after deforestation and intensive cultivation. With the main objective to estimate the SOM balances in a subtropical soil we determined the dynamics of SOM in a degraded yerba mate (Ilex paraguaiensis Saint Hil.) plantation introduced after deforestation and with elephant grass (Pennisetum purpureum L.) as a cover crop. The study site was in Misiones, Argentina, and we use the natural 13C abundance methodology and a descriptive model. The study was conducted on three contiguous 50 x 100 m plots of a typic Kandihumult soil with: (i) native forest, (ii) 50 years of continuous yerba mate monoculture with intensive tillage, and (iii) yerba mate associated with elephant grass as a cover crop and no tillage. We determined bulk density, carbon (C), nitrogen (N) and 13C content of the soil (0 - 0.05, 0.05 - 0.15 m layers) and the grass biomass. Yerba mate monoculture reduced soil C and N content as well as porosity at 0 - 0.15 m depth by 43 and 23%, respectively, as compared to the native forest. After ten years of yerba mate - elephant grass association soil C and N contents at the same depth increased by 19 and 12%, respectively, compared to the yerba mate monoculture, while soil porosity remained similar. Total C input,13C, and soil organic C were incorporated into a three compartment model to evaluate elephant grass C dynamics. Through the natural 13C abundance methodology we tracked the elephant grass C incorporation and the "old" soil C loss, and determined the model parameters - humification (k1) and mineralization (k) coefficients and stable C (Cs)- unambiguously. The high k1 and k predicted by the model are probably explained by elephant grass root system incorporation under no tillage and humid subtropical climate, respectively. In soil under yerba mate monoculture, Cs was counted as 91% of the total soil organic C

    Purification and characterization of Taq polymerase: A 9-week biochemistry laboratory project for undergraduate students

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    We have developed a 9-week undergraduate laboratory series focused on the purification and characterization of Thermus aquaticus DNA polymerase (Taq). Our aim was to provide undergraduate biochemistry students with a full-semester continuing project simulating a research-like experience, while having each week\u27s procedure focus on a single learning goal. The laboratory series has been taught for the past 7 years, and survey-based assessment of the effectiveness of the laboratory series was completed during the 2006 and 2007 fall semesters. Statistical analysis of the survey results demonstrate that the laboratory series is very effective in teaching students the theory and practice of protein purification and analysis while also demonstrating positive results in more broad areas of scientific skill and knowledge. Amongst the findings, the largest reported increases in knowledge were related to students\u27 understanding of how patent law relates to laboratory science, a topic of great importance to modern researchers that is readily discussed in relation to Taq polymerase. Overall, this laboratory series proves to be a very effective component in the curricula of undergraduate biology and chemistry majors and may be an appropriate laboratory experience for undergraduates. © 2010 by The International Union of Biochemistry and Molecular Biology
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