130,560 research outputs found
Labelling of video images : the first step to develop an automatic monitoring tool of pig aggression
No full textAggressive behaviour in pigs is a serious issue in pig farming since it poses enormous welfare and economic problems in livestock management. Mixing animals usually results in aggression among the group members because the animals have to establish a social hierarchy. At times, this aggressive behaviour can become so intense that animals seriously injure themselves or their pen mates. To immediately identify aggression is therefore extremely important for the farmer in order to limit the economical losses and to increase the welfare of the animals. By using video analysis, it is possible to develop an automatic monitoring technology that is able to detect aggression in pigs. Applying a non-invasive technology such as cameras is a very powerful approach since it does not intrude into the animals' hierarchy and is at the same time highly cost efficient. To develop such a product, it is first required that ethologists observe video images and label the behaviour of the animals in order to define the Golden Standard. This step is very crucial, but time-consuming since it demands hours and hours of observation. This paper describes a tool for helping experts in the observation and manual labelling of specific behaviours, for example aggression
Studies of the Alkaline Degradation of Cellulose and the Isolation of Isosaccharinic Acids
No full textCellulosic materials are expected to form a significant proportion of the waste proposed for disposal in underground repositories being designed for the storage of radioactive waste. Under the alkaline conditions of these facilities, cellulose degrades by a so called „peeling‟ reaction resulting in the production of a complex mixture of products (CDPs), the major components being α- and β isosaccharinic acid (α and β-ISA). A significant amount of research has been performed on ISA as part of the safety assessment for the development of these underground repositories due to the ability of ISA to complex with, and increase the solubility of radioactive isotopes. Until now, the vast majority of this research has involved the readily-available α-ISA, only a limited number of studies have involved β-ISA because no simple procedure is available for its isolation. Therefore, in this project, a method for the synthesis and isolation of β-ISA was developed.
Cellulose degradation experiments which were performed to maximise solution concentrations of β-ISA are described in chapter 3. Microcrystalline cellulose was degraded under anaerobic conditions at either RT, 50 °C or 90 °C and comparisons were made between the use of NaOH and Ca(OH)2 as the base catalyst. As expected, the major products of all degradation reactions were α- and β-ISA, in addition, small amounts of free metasaccharinic acid (MSA) was detected in the Ca(OH)2 reactions. The largest solution concentrations of β-ISA were produced when cellulose was degraded at 90 °C using NaOH; after 24 hrs of reaction, solution concentrations of 12.7 g L-1 were achieved, whereas, in the equivalent Ca(OH)2 reaction, after 4 days a maximum concentration of only 5.1 g L-1was produced. For this reason, cellulose was degraded at 90 °C using NaOH to produce degradation solutions to be used in procedures to isolate β ISA. An additional finding was that significant amounts of ISA were being removed from degradation solutions due to absorption on to unreacted cellulose fibres; in the NaOH reaction, absorption was occurring rapidly and the percentage of ISA in both the solution and solid phases were very similar. In the Ca(OH)2 reaction, the absorption was a slow process and the percentage of ISA on the solid phase (61 %) was lower than the percentage of ISA in the solution phase (84 %) suggesting that solid Ca(OH)2 was affecting both the rate at which absorption was occurring and the composition of the absorbed species; this was possibly due to solid Ca(OH)2 physically obstructing the access of ISA to the cellulose fibres and also catalysing the oxidation of some of the ISA into smaller fragmentation products.
Methods which were developed to isolate β-ISA are described in chapter 4. Isolation of β-ISA was initially achieved by eluting crude cellulose degradation solutions directly through a column of anion exchange resin. Using an automated system, a large throughput of material was possible resulting in the accumulation of relatively large amounts of β-ISA; after repeating the column 17 times, 1 g of pure β-ISA was isolated. However, using this method, the crude solutions severely fouled the anion exchange resin, concluding that anion exchange was more suited to small scale isolations of β-ISA. A final isolation procedure was developed which involved the elution of mixtures of benzoylated CDPs through normal phase silica columns. It was determined that prior to elution, coloured impurities could be efficiently removed by passing the derivatised mixture through a wide bed of silica. Slow elution of the resulting clean syrup through a large silica column allowed up to 7 g of tribenzoylated β-ISAL to be isolated and following de-benzoylation procedures, 2.6 g of β-ISA was isolated from a single column. The large protecting groups also allowed single crystals of both α- and β-tribenzoate to be produced and the resulting X-ray structures confirmed the absolute configuration of tribenzoylated β-ISAL as being 2R, 4S. Additional NMR analysis of collected fractions allowed several other polyhydroxylated compounds to be identified, also present as their perbenzoylated esters, these being: 3,4-dihydroxybutanoic acid, 2,5-dihydroxypentanoic acid, 2,3-dideoxypentanoic acid and 2,4,5-trihydroxypentanoic acid.
The isolation of large amounts of β-ISA allowed several solution phase physical properties of β ISA to be measured and these are reported in chapter 5, including the aqueous pKa (3.61) which was determined using NMR methods. The rate constants for the inter-conversion between ISAH and ISAL were also studied for both α- and β-ISA. In acidic environments, ISAH undergoes an acid catalysed lactonisation to generate isosaccharino-1,4-lactone (ISAL), conversely in basic environments, ISAL undergoes a base catalysed ring-opening to produce ISAH. Using pH-stat autotitration, the second-order rate constants for the lactone hydrolysis reaction were determined, to which values of 25.3 M-1 s-1 for β-ISAL and 97.0 M-1 s-1 for α-ISAL were observed. The acid catalysed lactonisation of ISAH was studied using 1H NMR spectroscopy; the second-order rate constant for the lactonisation of β-ISAH (3.10 x 10-3 M-1 s-1) was larger than the second order rate constant for the lactonisation of α-ISAH (7.04 x 10-4 M-1 s-1)
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Scholarly Communication and Publishing Lunch and Learn Talk #11: The ULS Open Access Author Fee Fund
No full textAt the May 2014 talk, you will learn about the ULS Open Access Author Fee Fund--what it is, why we do it, how it works, and how the program is going so far
The R&D Tax Incentives
No full textThis article sets out some background information and reflections of the author on the R&D tax incentive schemes included in the Common Corporate Tax Base (CCTB) Proposal. In particular the author analyzes the stimulus to private R&D through ad hoc tax incentives included in the CCTB Proposal and dives into the actual provisions included in the Proposal highlighting the most relevant issues connected with their design and interpretation. Moreover, the author explores the interaction between the CCTB Proposal and the granting by Member States of domestic R&D tax incentives
Antiproliferative activities of chalepin and rutamarin isolated from Ruta angustifolia on selected cancer cell lines / Musa Isah Fakai
No full textChalepin and rutamarin isolated from the chloroform fraction of Ruta angustifolia were screened against selected cancer lines namely the human hormone-dependent breast cancer cell (MCF7), human non-hormone-dependent breast cancer cell (MDA-MB-231), human colon cancer cell (HT29), human colon carcinoma cell (HCT116) and a normal lung fibroblast cell line (MRC-5). Phytochemical investigation on the active chloroform extract led to the isolation of chalepin and rutamarin using HPLC. These compounds were then, identified by GC-MS and NMR analysis. This was followed by cytotoxicity screening using SRB assay. Based on the IC50 at the lower time point, chalepin was further investigated for its apoptotic induction on MCF7 cell through morphological analysis using both phase contrast and fluorescence microscopy; and established biochemical assays. Western blot analysis was also conducted on MCF7 treated with chalepin. For HT29 cells, rutamarin treatment followed by downstream study on protein profiling by LC-MS approach as well as western blot analysis was performed as there were no previously reported study. The active chloroform extract showed relatively higher cytotoxic activity against MCF7, MDA-MB-231, and HT29, but no activity against MRC5 (IC50 > 100g/mL). Chalepin displayed remarkable cytotoxicity against all tested cancer cell lines but no activity against MRC-5. Rutamarin on the other hand, showed remarkable cytotoxic activity only on MCF7 and HT29, whereas no activity against MDA-MB-231 and MRC5 was observed. In this study, morphological examinations identified typical apoptotic features such as membrane blebbing, chromatin condensation, DNA fragmentation, and apoptotic body formation. Phosphatidylserine externalisations, DNA fragmentation, and caspase-3 activity significantly increased whereas mitochondrial membrane potential significantly decreased in chalepin treated MCF7 cells as compared to untreated cells. Western blots results showed that the expression of pro-apoptotic proteins such as caspases, Bid and P53 were upregulated whereas cell cycle regulatory proteins such as CDK2, CDK4, cyclin A, and cyclin D were downregulated. Similarly, EGFR and its downstream cascades; (PI3K-AKT; JAK-STAT3 and Erk pathways) were also downregulated. The apoptotic effect of chalepin against MCF7 was a dose and time-dependent manner. On the other hand, Western blot results on HT29 treated with rutamarin shows that the expression of pro-apoptotic proteins such as caspases, Bid, P21, P27, and P53 was upregulated whereas cell cycle regulatory proteins such as CDK2, CDK4, cyclin A, and cyclin D were downregulated. Similarly, EGFR and its downstream cascades (PI3K-AKT; JAK-STAT3 and Erk pathways) were also downregulated. Results from proteomic profiling indicates that 2056 proteins were identified from both untreated and 6 hours rutamarin treated HT29. Following filtrations, at various levels, only 756 proteins were used for the analysis. Consequently, two sample t-test show that only one protein; mitochondrial carrier homolog 2 (MTCH2) (Q9Y6C9) was identified to be upregulated in 6 hours, whereas profile plot analysis indicated 20 proteins are having a similar pattern including the differentially expressed protein. These initial results, therefore suggest that chalepin and rutamarin may serve as potential anticancer agents that warrant further in-depth investigations
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