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We report herein a new method for the synthesis of densely functionalized chiral allyl SCF3, SCF2R, SCN and SAr species with a separate CF3 functionality. The synthetic approach is based on selenium‐catalyzed sulfenofunctionalization of chiral α‐CF3 allylboronic acids. The reactions proceeded with remarkably high stereo‐, diastereo‐ and site‐selectivity, based on the formation of a stable thiiranium ion followed by rapid deborylative ring opening. [ABSTRACT FROM AUTHOR]

We report herein a new method for the synthesis of densely functionalized chiral allyl SCF3, SCF2R, SCN and SAr species with a separate CF3 functionality. The synthetic approach is based on selenium‐catalyzed sulfenofunctionalization of chiral α‐CF3 allylboronic acids. The reactions proceeded with remarkably high stereo‐, diastereo‐ and site‐selectivity, based on the formation of a stable thiiranium ion followed by rapid deborylative ring opening. [ABSTRACT FROM AUTHOR]

The frequency dependence of the longitudinal relaxation rate, known as the magnetic relaxation dispersion (MRD), can provide a frequency-resolved characterization of molecular motions in complex biological and colloidal systems on time scales ranging from 1 ns to 100 μs. The conformational dynamics of immobilized proteins and other biopolymers can thus be probed in vitro or in vivo by exploiting internal water molecules or labile hydrogens that exchange with a dominant bulk water pool. Numerous water 1H and 2H MRD studies of such systems have been reported, but the widely different theoretical models currently used to analyze the MRD data have resulted in divergent views of the underlying molecular motions. We have argued that the essential mechanism responsible for the main dispersion is the exchange-mediated orientational randomization (EMOR) of anisotropic nuclear (electric quadrupole or magnetic dipole) couplings when internal water molecules or labile hydrogens escape from orientationally confining macromolecular sites. In the EMOR model, the exchange process is thus not just a means of mixing spin populations but it is also the direct cause of spin relaxation. Although the EMOR theory has been used in several studies to analyze water 2H MRD data from immobilized biopolymers, the fully developed theory has not been described. Here, we present a comprehensive account of a generalized version of the EMOR theory for spin I = 1 nuclides like 2H. As compared to a previously described version of the EMOR theory, the present version incorporates three generalizations that are all essential in applications to experimental data: (i) a biaxial (residual) electric field gradient tensor, (ii) direct and indirect effects of internal motions, and (iii) multiple sites with different exchange rates. In addition, we describe and assess different approximations to the exact EMOR theory that are useful in various regimes. In particular, we consider the experimentally important dilute regime, for which approximate analytical results are derived. As shown by the analytical expressions, and confirmed by exact numerical calculations, the dispersion is governed by the pure nuclear quadrupole resonance frequencies in the ultraslow-motion regime, where the relaxation rate also exhibits a much stronger dependence on the electric field gradient asymmetry than in the motional-narrowing regime. [ABSTRACT FROM AUTHOR]

Abstract: Hydroperoxides of 18:2n-6 and 20:4n-6 were obtained by autoxidation and photooxidation. The enantiomers were separated as free acids (Reprosil Chiral-NR column, eluted with hexane containing 1–1.2% alcoholic modifier) and analyzed by on line UV detection (234nm) and liquid chromatography-MS/MS/MS of carboxylate anions (A− →(A−-18)→full scan) in an ion trap. The combination of UV and MS/MS/MS analysis facilitated identification of hydroperoxides even in complex mixtures of autoxidized or photooxidized fatty acids. The signal intensities increased about two orders of magnitude by raising the isolation width of A− from 1.5amu to 5 or 10amu for cis-trans conjugated hydroperoxy fatty acids, and one order of magnitude or more for non-conjugated hydroperoxy fatty acids. The S enantiomer of 8-, 9-, 10-, and 13-hydroperoxyoctadecadienoic acids and the S enantiomer of cis-trans conjugated hydroperoxyeicosatetraenoic acids eluted before the corresponding R enantiomer with two exceptions (11-hydroperoxylinoleic acid and 8-hydroperoxyeicosa-5Z,9E,11Z,14Z-tetraenoic acid). The separation of enantiomers or regioisomers could be improved by the choice of either isopropanol or methanol as alcoholic modifier. [Copyright &y& Elsevier]

U.S. consumers are increasingly concerned about food safety, environmental degradation, and animal welfare at the live animal production stage. In response, meat suppliers are developing food credence certification to secure market access, increase margins, and increase overall demand. The objective of this paper is to characterize the demand and the market potential of a credence certification program for pork in the United States. Information regarding consumer willingness to pay for the conventional and certified products is derived from a latent class random utility model. The willingness to pay estimates are subsequently compared to the costs of implementing the programs at the producer, packing, and retailing stages. One of the findings in this study is that a significant segment of consumers would purchase certified pork at the anticipated marginal cost of certification. Therefore, future studies should consequently focus on the welfare economic implications on consumers and meat suppliers from incomplete adoption of voluntary certification programs on the part of both producers and consumers. Aux États-Unis, les consommateurs se préoccupent de plus en plus de la sécurité alimentaire, de la dégradation de l'environnement et du bien-être des animaux au stade de la production. En réponse à ces inquiétudes, les fournisseurs de viande travaillent à l'élaboration de programmes de certification des aliments pour garantir l'accès au marché, accroître les marges ainsi que la demande globale. Le présent article vise à caractériser la demande et le potentiel de marché d'un programme de certification du porc aux États-Unis. L'information concernant la volonté de payer du consommateur pour des produits classiques et des produits certifiés a été tirée d'un modèle d'utilité aléatoire à structure latente. Les estimations de la volonté de payer ont ensuite été comparées aux coûts de mise en place des programmes aux stades de la production, de l'abattage et de la vente au détail. L'un des résultats de l'étude a montré qu'un nombre important de consommateurs achèterait du porc certifié au coût marginal prévu de la certification. Des études ultérieures devraient donc se pencher sur les répercussions économiques de l'adoption incomplète des programmes de certification volontaires de la part des producteurs et des consommateurs sur le bien-être des consommateurs et des fournisseurs de viande. [ABSTRACT FROM AUTHOR]

Side member left and side member right, which go from bumper to bumper in a car body, were at the focus in the present study. These side members were produced using straight round (hollow with a circular cross-section) extruded aluminium profiles as tube material. The tubes were bent and hydroformed. Rotary-draw bending yielded the best result. A spread within 8 mm after bending was found to be acceptable provided that the bent tube was hydroformed with a high maximum internal pressure (1300 bar in this study). Pressure-assisted tool closure (hydroforming tool) should be preferred. Such a tool closure prevents formation of buckles, which may be difficult to straighten out completely during hydroforming. Planeness and parallelity of the press tables and adapters play a significant role, as far as the spread and inplaneness of hydroformed components are concerned. The hydroforming tool must be matched in the press that actually will be used. Proper evacuation (of particularly air) is essential, especially in long hydroforming tools. All cross-sections must be deformed at least 2% (average perimeter enlargement) if the hydroformed components are to exhibit a reasonable spread. The critical (fracture) cross-sections predicted by finite-element simulation corresponded to those found in practice. However, the finite-element simulation was not able to predict formation of wrinkles at the tube ends caused by excessively large strokes. Such wrinkles were obtained in practice. [Copyright &y& Elsevier]

A low-field theory for paramagnetic relaxation enhancement (PRE), appropriate for the outersphere relaxation, is presented for the electron spin quantum number S = 1, 3/2, 2, 5/2, 3 and 7/2. The theory is used to calculate the PRE at low magnetic field, as a function of the translational diffusion coefficient, for various values of the electron spin quantum number, for small and fairly large values of the static zero-field splitting (ZFS), and for a given set of parameters determining the electron spin relaxation. We have found earlier that the static ZFS has a profound influence on the electron spin relaxation; such effects are also evident in the present study. Comparisons are made with other existing models for the outer-sphere PRE, and significant differences are found for slowly diffusing systems with large ZFS. The theory is also used to obtain a novel interpretation of experimental data for an acetone solution of a Mn(III) complex. [ABSTRACT FROM AUTHOR]

A 41-year-old woman with SAPHO syndrome presented with numbness of her left arm followed by a generalized seizure. Computed tomography and magnetic resonance imaging of the brain revealed a small ring enhancing lesion in the right parietal lobe with adjacent meningeal thickening and enhancement. Surgical removal and histopathology showed evidence of severe chronic sterile inflammation and no malignant cell. Symptoms recurred and a lesion were again detected on radiological follow-up, but improvement occurred following treatment with antibiotics and biphosphonate, achieving a low inflammatory activity, reduction in CNS lesions and relative clinical well-being. This is a first report in literature about the central nervous system involvement in a patient with SAPHO syndrome. [ABSTRACT FROM AUTHOR]

AgriStability is the primary Canadian agricultural risk management program. Recent experience with bovine spongiform encephalopathy (BSE) in the cattle sector demonstrated that output prices are susceptible to both “normal” risk and sudden, “catastrophic” declines. This paper evaluates the AgriStability program for cow-calf producers when there is potential for catastrophic price risk. A simulation model is developed. Under a base case scenario, when there is no catastrophic price risk, AgriStability behaves more like an income support program than a risk management tool. Risk-neutral producers see a 12.1% increase in certainty equivalent wealth compared to 12.5% for moderately risk-averse producers. Introducing catastrophic price risk increases risk-averse producers’ expected benefits to 21.8%. Actuarially fair program premiums and implied subsidies are also estimated. These results demonstrate that AgriStability is highly subsidized. Finally, benefits from supplementary catastrophic revenue insurance are calculated and discussed, along with several additional structural features of the program. Agri-stabilité constitue le principal programme canadien de gestion des risques en agriculture. L'encéphalopathie spongiforme bovine qui a frappé le secteur de l’élevage bovin a démontré que les prix des extrants sont exposés à des risques « normaux » et à des chutes soudaines et « catastrophiques ». Le présent article évalue le programme Agri-stabilité dans le cas des producteurs vache-veau (veaux d’embouche) lorsqu’un potentiel de risque de prix catastrophique existe. Nous avons élaboré un modèle de simulation. Dans le cadre d’un scénario de référence, lorsqu’il n’existe pas de risque de prix catastrophique, le programme Agri-stabilité ressemble davantage à un programme de soutien du revenu qu’à un outil de gestion des risques. Dans le cas des producteurs indifférents aux risques, l’équivalent certain de la richesse aléatoire est supérieur de 12,1 % comparativement à 12,5 % dans le cas des producteurs modérément risquophobes. L'introduction de risque de prix catastrophique augmente les bénéfices espérés des producteurs risquophobes de 21,8 %. Nous avons également estimé ce que représentent les indemnités actuariellement justes ainsi que les subventions implicites. Les résultats ont montré que le programme Agri-stabilité est très subventionné. Finalement, nous avons examiné et calculé les indemnités tirées d’une assurance-revenu supplémentaire en cas de risque catastrophique et nous avons aussi analysé plusieurs autres caractéristiques structurelles du programme. [ABSTRACT FROM AUTHOR]

Abstract: Hydroperoxides of polyunsaturated fatty acids can be transformed to epoxyalcohols and keto fatty acids by metal enzymes, hematin, and various catalysts. In the current study, we used hematin to transform 9-hydroperoxy-10E,12Z-octadecadienoic acid and 13-hydroperoxy-9Z,11E-octadecadienoic acid to epoxyalcohols (with trans epoxide configuration) and to keto fatty acids. The products were separated by normal phase high-performance liquid chromatography (NP-HPLC) and analyzed using postcolumn addition of isopropanol/water and online negative ion electrospray ionization mass spectrometry (MS). The tandem MS (MS/MS) spectra were studied using analogs prepared from [9,10,12,13-2H4]linoleic acid (18:2n−6) and from α-linolenic acid (18:3n−3). We also studied the MS/MS spectra of epoxyalcohols formed from 11-hydroperoxy- and 8-hydroperoxy-9Z,12Z-octadecadienoic acids. Results were confirmed by MS/MS analysis of a series of authentic standards. MS/MS ions of 9-keto-10E,12Z-octadecadienoic acid and 13-keto-9Z,11E-octadecadienoic acid could be explained by keto–enol tautomerism. MS/MS spectra of regioisomeric allylic epoxyalcohols differed in relative intensities of characteristic ions. The MS/MS spectra of the epoxyalcohols with 1-hydroxy-2,3-epoxy-4Z-pentene or 3-hydroxy-1,2-epoxy-4Z-pentene elements were virtually identical and showed two characteristic ions that differed by 30 in m/z values (CH(OH)). The results suggested that epoxide migration (Payne rearrangement) occurred during collision-induced dissociation. We conclude that regioisomeric allylic epoxyalcohols can be identified by their MS/MS spectra, whereas regioisomeric epoxyalcohols can be identified by MS/MS in combination with their retention times on NP-HPLC. [Copyright &y& Elsevier]

Background: Patients with Down syndrome are prone to autoimmune diseases which also occur in the recessive disease autoimmune polyendocrine syndrome type I (APS I). Since this disease is caused by mutations in the gene AIRE on chromosome 21, one might speculate that altered expression of AIRE contributes to autoimmune disease in Down syndrome. Aim: To study the prevalence of 11 well-defined autoantibodies, five of which are specific for APS I, associated with various manifestations of APS I in patients with Down syndrome. Methods: Sera from 48 patients with Down syndrome were analysed. Autoantibodies against 21-hydroxylase, 17α-hydroxylase, side-chain cleavage enzyme, aromatic L-amino acid decarboxylase, cytochrome P4501A2, tyrosine hydroxylase, tryptophan hydroxylase, glutamic acid decarboxylase 65, tyrosine phosphatase IA-2 and transglutaminase were analysed using an immunoprecipitation assay, and thyroid peroxidase autoantibodies were measured using a haemagglutination assay. Results: Seven of 48 patients had elevated titres of autoantibodies: one against 21-hydroxylase, three against aromatic L-amino acid decarboxylase, one against cytochrome P4501A2, one against glutamic acid decarboxylase 65 and one against tyrosine phosphatase IA-2. None of the patients had clinical or laboratory signs of disease coupled to the respective autoantibody.Conclusion: Four patients with Down syndrome had autoantibodies hitherto regarded as unique for APS I, which may suggest a dysregulation of AIRE. [ABSTRACT FROM AUTHOR]