67 resultados para Andronicus I,Commenus, Emperor of the East, d. 1185.
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We develop a theoretical model of enforcement and compliance under HACCP regulation and use the FDA's seafood inspection records to examine: (1) if the FDA has targeted its inspections under HACCP regulation; (2) the effects of inspections on compliance with HACCP and plant sanitation standards; and (3) the relationship between compliance with HACCP and preexisting sanitation standards. There is some evidence of targeting based on product risk, but not on past compliance performance. The threat of an inspection increases the likelihood of compliance, but only for sanitation inspections, not for HACCP. HACCP compliance does not improve compliance with sanitation standards. © 2008 American Agricultural Economics Association.
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Electron-impact excitation data for He-like ions are of significant importance for diagnostic applications to both laboratory and astrophysical plasmas. Here we report on the first fully relativistic R -matrix calculations with radiation damping for the He-like ions Fe 24+ and Kr 34+ . Effective collision strengths for these two ions have been determined with and without damping over a wide temperature range for all transitions between the 49 levels through n = 5. We find that damping has a pronounced effect on the effective collision strengths for excitation to some of the low-lying levels, but its effect on excitation to the vast majority of levels is small. At the energy of a resonance peak, we also investigate the effect of radiation damping on the angular distribution of scattered electrons. Finally, we compare our results for Fe 24+ with an earlier intermediate coupling frame transformation R -matrix calculation with radiation damping by Whiteford et al ( J. Phys. B: At. Mol. Opt. Phys. 34 3179) and find good agreement, especially for excitation to the lower levels.
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A high-resolution crystal structure is reported for d(TpA)*, the intramolecular thymine–adenine photoadduct that is produced by direct ultraviolet excitation of the dinucleoside monophosphate d(TpA). It confirms the presence of a central 1,3-diazacyclooctatriene ring linking the remnants of the T and A bases, as previously deduced from heteronuclear NMR measurements by Zhao et al. (The structure of d(TpA)*, the major photoproduct of thymidylyl-(3'-5')-deoxyadenosine. Nucleic Acids Res., 1996, 24, 1554–1560). Within the crystal, the d(TpA)* molecules exist as zwitterions with a protonated amidine fragment of the eight-membered ring neutralizing the charge of the internucleotide phosphate monoanion. The absolute configuration at the original thymine C5 and C6 atoms is determined as 5S,6R. This is consistent with d(TpA)* arising by valence isomerization of a precursor cyclobutane photoproduct with cis–syn stereochemistry that is generated by [2 + 2] photoaddition of the thymine 5,6-double bond across the C6 and C5 positions of adenine. This mode of photoaddition should be favoured by the stacked conformation of adjacent T and A bases in B-form DNA. It is probable that the primary photoreaction is mechanistically analogous to pyrimidine dimerization despite having a much lower quantum yield.
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H. Kanaseki, Editor. 2003, UNESCO-Cultural Heritage Protection Office: Horen-Cho, Nara.
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Background. Vitamin D and its analogues are reported to have renoprotective effects in chronic kidney disease including diabetic nephropathy (DN). Vitamin D3 is converted to 1,25(OH) D3 by CYP2R1 and CYP27B1. The biological action of 1,25(OH) D3 is mediated via its receptor. VDR, CYP27B1 or CYP2R1 gene variants could modify the biological activity of vitamin D3. We have conducted the first case- control association study to determine the relationship between polymorphisms in VDR, CYP27B1 and CYP2R1 genes, and the risk of DN in individuals with type 1 diabetes.
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The food industry is moving towards the use of natural sweeteners such as those produced by Stevia rebaudiana due to the number of health and safety concerns surrounding artificial sweeteners. Despite the fact that these sweeteners are natural; they cannot be assumed safe. Steviol glycosides have a steroidal structure and therefore may have the potential to act as an endocrine disruptor in the body. Reporter gene assays (RGAs), H295R steroidogenesis assay and Ca(2+) fluorimetry based assays using human sperm cells have been used to assess the endocrine disrupting potential of two steviol glycosides: stevioside and rebaudioside A, and their metabolite steviol. A decrease in transcriptional activity of the progestagen receptor was seen following treatment with 25,000 ng/ml steviol in the presence of progesterone (157 ng/ml) resulting in a 31% decrease in progestagen response (p=<0.01). At the level of steroidogenesis, the metabolite steviol (500-25,000 ng/ml) increased progesterone production significantly by 2.3 fold when exposed to 10,000 ng/ml (p=<0.05) and 5 fold when exposed to 25,000 ng/ml (p=<0.001). Additionally, steviol was found to induce an agonistic response on CatSper, a progesterone receptor of sperm, causing a rapid influx of Ca(2+). The response was fully inhibited using a specific CatSper inhibitor. These findings highlight the potential for steviol to act as a potential endocrine disruptor.
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The successful career of Dean Mahomet (1759-1851) as a migrant from India to Ireland (and later, England) has led to scholarly and popular interest in his work. His Travels through several parts of India in the Service of the Honourable East India Company (1794) published by subscription in Cork is reputedly the first English book by an Indian, and has been seen to counterbalance the many accounts of India by western travellers, and to assert, in autobiographical form, his identity as an Indian in 1790s Ireland. My paper analyses this text in relation to moral and economic criticisms of the East India Company in the eighteenth century, and in particular to legislation of 1793 which defined the role of the Company in Ireland’s trade with the east. These aspects of colonial politics involving Ireland and India as subject nations of Britain are shown to shape Mahomet’s discursive strategies and the complex identity produced in his text.
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A convenient asymmetric total synthesis of the potent HIF-1 inhibitory antitumor natural product, (−)- or (+)-(8R)-mycothiazole (1), is described. Not only does our synthesis confirm the 2006 structural reassignment made by Crews (Crews, P., et al. J. Nat. Prod</i>. 2006, 69, 145), it revises the [α]D</sub> data previously reported for this molecule in MeOH from −13.7° to +42.3°. The newly developed route to (8R)-1 sets the C(8)–OH stereocenter via Sharpless AE/2,3-epoxy alcohol reductive ring opening and utilizes two Baldwin–Lee CsF/cat. CuI Stille cross-coupling reactions with vinylstannanes 8 and 3 to efficiently elaborate the C(1)–C(4) and C(14)–C(18) sectors.
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While we can usually understand the impacts of invasive species on recipient communities, invasion biology lacks methodologies that are potentially more predictive. Such tools should ideally be straightforward and widely applicable. Here, we explore an approach that compares the functional responses (FRs) of invader and native amphipod crustaceans. Dikerogammarus villosus is a Ponto-Caspian amphipod currently invading Europe and poised to invade North America. Compared with other amphipods that it actively replaces in fresh-waters, D. villosus exhibited significantly greater predation, consuming significantly more prey with a higher type II FR. This corroborates the known dramatic field impacts of D. villosus on invaded communities. In another species, FRs were nearly identical in invasive and native ranges. We thus propose that if FRs of other taxa and trophic groups follow such general patterns, this methodology has potential in predicting future invasive species impacts.
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This paper investigates the characteristics of silicon piezoresistors with various doping concentrations and Length/Width dimensions at micro level. The silicon piezoresistors have been produced by conventional fabrication methods. The measurements are conducted on silicon test chips where p type resistors are fabricated on n type (100) silicon substrates along the <110> direction. A four point bending setup has been designed and fabricated for characterizing the piezoresistor sets. The four point bending setup is used to apply uniform uniaxial stress along the <110> direction. This experimental result demonstrates a good linear relationship between resistance change and stress applied. The effect of doping concentration on temperature sensitivity is also investigated.
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Molecularly adsorbed CO on Pd{110} has been shown (R. Raval et al., Chem. Phys. Lett. 167 (1990) 391, ref. [1]) to induce a substantial reconstruction of the surface in the coverage range 0.3 <theta less-than-or-equal-to 0.75. Throughout this coverage range, the adsorbate-covered reconstructed surface exhibits a (4 x 2) LEED pattern. However, the exact nature of the reconstruction remains uncertain. We have conducted a LEED I(E) "fingerprinting" analysis of the CO/Pd{110}-(4 x 2) structure in order to establish the type of reconstruction induced in the metal surface. This study shows that the LEED I(E) profiles of the integral order and appropriate half-order beams of the CO/Pd{110}-(4 x 2) pattern closely resemble the I(E) profiles theoretically calculated for a Pd{110}-(1 x 2) missing-row structure. Additionally, there is a strong resemblance to the experimental LEED I(E) profiles for the Cs/Pd{110}-(1 x 2) structure which has also been shown to exhibit the missing-row structure. On the basis of this evidence we conclude that the CO/Pd{110}-(4 x 2) LEED pattern arises from a missing-row reconstruction of the Pd{110} surface which gives rise to a strong underlying (1 x 2) pattern plus a poorly ordered CO overlayer which produces weak, diffuse fourth-order spots in the LEED pattern.