998 resultados para Map collections


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Background: The insecticides dichlorvos, paradichlorobenzene and naphthalene have been commonly used to eradicate pest insects from natural history collections. However, it is not known how these chemicals affect the DNA of the specimens in the collections. We thus tested the effect of dichlorvos, paradichlorobenzene and naphthalene on DNA of insects (Musca domestica) by extracting and amplifying DNA from specimens exposed to insecticides in two different concentrations over increasing time intervals. Results: The results clearly show that dichlorvos impedes both extraction and amplification of mitochondrial and nuclear DNA after relatively short time, whereas paradichlorobenzene and naphthalene do not. Conclusion: Collections treated with paradichlorobenzene and naphthalene, are better preserved concerning DNA, than those treated with dichlorvos. Non toxic pest control methods should, however, be preferred due to physical damage of specimens and putative health risks by chemicals.

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A thermomechanical processing (TMP) structure map is proposed that plots the critical strains required for dynamic recrystallization along with the grain sizes that result. These maps are useful in identifying the limits to grain refinement and designing hot working processes. They are readily constructed for well studied alloys such as plain carbon steel. In light of the recent interest in the hot working of magnesium, initial steps are taken here to construct a TMP structure map for the most common wrought magnesium alloy, AZ31. The completion of dynamic recrystallization is estimated using a geometrical approach and a twinning region is identified.

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Bullen and Parsons identify Anthony Browne's picture book Into the Forest as a re-gendered retelling of 'Little Red Riding Hood' that expresses recent assumptions about childhood, risk and the resources children need to survive in today's world. In Browne's version, the forest is the terrain in which a young male protagonist imaginatively explores his anxiety about his father's unexplained absence.

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Vanadate has insulin-like effects in adipocytes without stimulating insulin receptor kinase activity. However, it activates IRS-1 associated PI 3-kinase, suggesting that it mimics insulin effects by stimulating signaling elements downstream of PI 3-kinase. Here we analysed the stimulation of MAPK by insulin and vanadate and observed that both elicit a rapid 3.5–4 fold activation which is abolished by wortmannin and PD98059. Simultaneous addition of insulin and vanadate does not result in an additive effect neither on MAPK nor in MEK. Whereas insulin action is transient, vanadate stimulation lasts up to 20 min. In insulin-resistant adipocytes from old rats, insulin stimulates poorly MAPK, whereas a normal activation is achieved with vanadate. We conclude that: (a) insulin and vanadate use a common signaling pathway from PI 3-kinase to MEK and MAPK; (b) vanadate but not insulin, elicits a sustained activation of both enzymes; (c) this pathway is functional in old rat adipocytes.

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The valuation and depreciation of library collections is an increasing challenge in the context of financial accounting requirements. The depreciation implications of major collection management strategies have become of increasing concern to Deakin University library in regard to accrual accounting reporting procedures. Changes to library collections, such as the transition to online journals, are moving the financial value of library collections from capital to operating budgets. Major collection management projects such as weeding print assets can have unexpected implications for depreciation and library budgets. Gratis publication acquisitions can also significantly affect valuation and depreciation. Many other libraries are facing similar challenges and this paper will incorporate a range of experiences and practices.

There appears to be little consistency across libraries in how collections are valued and accounting procedures can differ greatly across institutions. The seemingly arbitrary and often questionable nature of financial policies in relation to library collections can create problems for libraries when used to inform decision making and budgets. Libraries increasingly need to work in partnership with financial managers to ensure the financial reporting requirements do not result in adverse implications for collections and budgets and that the capacity of the library to meet its strategic objectives is not impeded. This paper explores the issues and challenges facing many libraries and outlines some strategies to assist library managers in dealing with this financial conundrum

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Localization of RFIDs in the indoor environment will entail determining both the position and the orientation of the user. This paper develops estimator using RSSI measurements to predict the position and orientation of a transmitter in an indoor environment. The best estimator tried was an K-nearest neighbours model that gave an accuracy of approximately 83% for position prediction and 93% for orientation prediction. It was also found that the RSSI values change throughout the day, meaning that an adaptive estimator is necessary for localization.

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To determine the effect of glycogen availability and contraction on intracellular signaling and IL-6 gene transcription, eight males performed 60 min of exercise on two occasions: either with prior ingestion of a normal (Con) or low carbohydrate (LCHO) diet that reduced pre-exercise muscle glycogen content. Muscle biopsies were obtained and analyzed for IL-6 mRNA. In addition, nuclear proteins were isolated from the samples and analyzed for the mitogen- activated protein kinases (MAPK) c-jun amino-terminal kinase (JNK) 1 and 2 and p38 MAPK. Nuclear fractions were also analyzed for the phosphorylated forms of JNK (p-JNK) and p38 MAPK (p-p38 MAPK) and the abundance of the nuclear transcription factors nuclear factor of activated T cells (NFAT) and nuclear factor kappa-β (NF-κβ). No differences were observed in the protein abundance of total JNK 1/2, p38 MAPK, NFAT, or NF-κβ before exercise, but the nuclear abundance of p-p38 MAPK was higher (P<0.05) in LCHO. Contraction resulted in an increase (P<0.05) in nuclear p-JNK 1/2, but there were no differences when comparing CON with LCHO. The fold increase in IL-6 mRNA with contraction was potentiated (P<0.05) in LCHO. A correlation between pre-exercise nuclear phosphorylated p38 MAPK and contraction-induced fold increase in IL-6 mRNA was performed, revealing a highly significant correlation (r=0.96; P<0.01). We next incubated L6 myotubes in ionomycin (a compound known to induce IL-6 mRNA) with or without the pyridinylimidazole p38 MAPK inhibitor SB203580. Treatments did not affect total nuclear p38 MAPK, but ionomycin increased (P<0.05) both nuclear p-p38 MAPK and IL-6 mRNA. The addition of SB203580 to ionomycin decreased (P<0.05) nuclear p-p38 MAPK and totally abolished (P<0.05) the ionomycin- induced increase in IL-6 mRNA. These data suggest that reduced carbohydrate intake that results in low intramuscular glycogen leads to phosphorylation of p38 MAPK at the nucleus. Furthermore, phosphorylation of p38 MAPK in the nucleus appears to be an upstream target for IL-6, providing new insights into the regulation of IL-6 gene transcription.


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http://digitalcommons.colby.edu/atlasofmaine2005/1007/thumbnail.jpg

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http://digitalcommons.colby.edu/atlasofmaine2005/1026/thumbnail.jpg

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The aim of this project is to provide an explanation for recently obtained binding constants for two similar guest molecules, NDMG and N-MAP, with a p-sulfonatocalix[6]arene host in ammonium acetate buffer. This work was done primarily using pressure perturbation calorimetry, which is a technique that determines the coefficient of thermal expansion, α, which is in turn related to the solute molecule's effect on the order of the surrounding water molecules. A series of experiments were designed to test the effects of suspected confounding variables on the validity of PPC data. PPC was then used to study NDMG and N-MAP in ammonium acetate buffer. NDMG exhibited a minimum in α as function of temperature, while N-MAP did not. This difference was theorized to be due to the formation of an intramolecular hydrogen bond in monocationic NDMG that would lower the heat capacity of the molecule and better distribute the molecule's charge. Computational work and nuclear magnetic resonance spectroscopy confirmed that monocationic, ring-closed NDMG has less concentrated charge and more constrained motion than monocationic, ring-open NDMG. This evidence supports the theory that monocationic NDMG forms an intramolecular hydrogen bond and that this may be responsible for the minimum in α. This difference may explain the differences in binding constants between NDMG and N-MAP.