910 resultados para Wilt, Joshua


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The energetics of a fusion pathway is considered, starting from the contact site where two apposed membranes each locally protrude (as “nipples”) toward each other. The equilibrium distance between the tips of the two nipples is determined by a balance of physical forces: repulsion caused by hydration and attraction generated by fusion proteins. The energy to create the initial stalk, caused by bending of cis monolayer leaflets, is much less when the stalk forms between nipples rather than parallel flat membranes. The stalk cannot, however, expand by bending deformations alone, because this would necessitate the creation of a hydrophobic void of prohibitively high energy. But small movements of the lipids out of the plane of their monolayers allow transformation of the stalk into a modified stalk. This intermediate, not previously considered, is a low-energy structure that can reconfigure into a fusion pore via an additional intermediate, the prepore. The lipids of this latter structure are oriented as in a fusion pore, but the bilayer is locally compressed. All membrane rearrangements occur in a discrete local region without creation of an extended hemifusion diaphragm. Importantly, all steps of the proposed pathway are energetically feasible.

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The cysteinyl leukotrienes (cys-LTs) LTC4, LTD4, and LTE4 are a class of peptide-conjugated lipids formed from arachidonic acid and released during activation of mast cells (MCs). We now report that human cord-blood-derived MCs (hMCs) express the CysLT1 receptor, which responds not only to inflammation-derived cys-LTs, but also to a pyrimidinergic ligand, UDP. hMCs express both CysLT1 protein and transcript, and respond to LTC4, LTD4, and UDP with concentration-dependent calcium fluxes, each of which is blocked by a competitive CysLT1 receptor antagonist, MK571. Stably transfected Chinese hamster ovary cells expressing the CysLT1 receptor also exhibit MK571-sensitive calcium flux to all three agonists. Both hMCs and CysLT1 transfectants stimulated with UDP are desensitized to LTC4, but only partially to LTD4. Priming of hMCs with IL-4 for 5 days enhances their sensitivity to each agonist, but preferentially lowers their threshold for activation by LTC4 and UDP (≈3 log10-fold shifts in dose-response for each agonist) over LTD4 (1.3 log10-fold shift), without altering CysLT1 receptor mRNA or surface protein expression, implying the likely induction of a second receptor with CysLT1-like dual ligand specificity. hMCs thus express the CysLT1 receptor, and possibly a closely related IL-4-inducible receptor, which mediate dual activation responses to cys-LTs and UDP, providing an apparent intersection linking the inflammatory and neurogenic elements of bronchial asthma.

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Numerous human and animal studies indirectly implicate neurons in the anterior cingulate cortex (ACC) in the encoding of the affective consequences of nociceptor stimulation. No causal evidence, however, has been put forth linking the ACC specifically to this function. Using a rodent pain assay that combines the hind-paw formalin model with the place-conditioning paradigm, we measured a learned behavior that directly reflects the affective component of pain in the rat (formalin-induced conditioned place avoidance) concomitantly with “acute” formalin-induced nociceptive behaviors (paw lifting, licking, and flinching) that reflect the intensity and localization of the nociceptive stimulus. Destruction of neurons originating from the rostral, but not caudal, ACC reduced formalin-induced conditioned place avoidance without reducing acute pain-related behaviors. These results provide evidence indicating that neurons in the ACC are necessary for the “aversiveness” of nociceptor stimulation.

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Atualmente, a produtividade do feijoeiro comum (Phaseolus vulgaris L.) pode ser reduzida devido à ocorrência de doenças em todo o território nacional, destacando-se a murcha de fusário, causada por Fusarium oxysporum f. sp. phaseoli (Fop). No campo, o patógeno é disseminado a longas distâncias através das sementes infectadas e/ou contaminadas e a sua sobrevivência ocorre, principalmente, no solo. Os objetivos deste trabalho foram: avaliar a inibição do crescimento micelial de Fop por Trichoderma spp.; classificar a sensibilidade in vitro de Fop e Trichoderma spp., separadamente, a fungicidas e verificar a compatibilidade entre fungicidas químicos e biológicos para controle de Fop, presente nas sementes e no solo. Para avaliar a inibição do crescimento micelial de Fop, foram utilizados três isolados do patógeno, os quais foram confrontados, in vitro, com três isolados de Trichoderma spp. em testes de cultura pareada e produção de metabólitos voláteis a 20-22°C. Os experimentos foram conduzidos em delineamento inteiramente casualizado, com cinco repetições para cada isolado de Trichoderma. Para a classificação da sensibilidade in vitro de Fop e Trichoderma a fungicidas, foram avaliados os mesmos isolados anteriormente utilizados. Foram comparados dez fungicidas, em doses entre 0 a 100 mg L-1 que foram ajustadas de acordo com a CI50 de cada fungicida. Com base na percentagem de inibição do crescimento micelial, foram estimados os valores da concentração inibitória de 50% (CI50) e 100% (CI100) e selecionaram-se os fungicidas compatíveis com Trichoderma spp. A compatibilidade entre tratamentos químico e biológico foi avaliada através da inoculação artificial de sementes de feijão com um isolado de Fop (IAC 11.299-1) e infestação do mesmo no solo. As sementes foram tratadas com os fungicidas fludioxonil, flutriafol e tiofanato metílico, e com os três produtos biológicos, separadamente e em misturas. Avaliou-se o efeito dos tratamentos por meio dos testes de sanidade, germinação, comprimento de plântulas, massa da matéria seca em laboratório e índice de velocidade de emergência e porcentagem de emergência em estufa não climatizada. O efeito protetor dos tratamentos foi verificado através do teste de transmissão do patógeno solo-planta. Todos os isolados de Trichoderma apresentaram antagonismo in vitro contra Fop. No teste de cultura pareada foi observada uma redução de 15 a 20% no crescimento micelial do patógeno. No teste de produção de metabólitos voláteis, o isolado T12-1086G05 foi responsável pela maior inibição do crescimento micelial de Fop (10 a 48%). Os testes de sensibilidade in vitro mostraram que tiofanato metílico, flutriafol e fludioxonil foram compatíveis com Trichoderma (CI50 > 2 mg L-1). Com exceção do flutriafol e do GF 422 isolados e em mistura, todos os tratamentos foram eficientes na erradicação de Fop nas sementes, sem afetar a sua qualidade fisiológica. No teste de transmissão, verificou-se que a incidência de Fop foi de 5 a 40% no hipocótilo e de 5 a 30% nas raízes de feijoeiro provenientes de sementes tratadas com os produtos.

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This project analyzes the closely linked connection between the competition over limited resources and the formation of culture as it pertains to art and literature. The project is broken into three main topics: the influence of limited resources on competition, the role that competition and other factors have on the formation of culture, and finally how art and literature are reflective of resources, the competition for those resources, and other historical influences. This paper concludes that while there are many factors in the creation of cultures, competition over limited natural resources plays the most integral role in the formation of culture.

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Marbled paper cover. Includes a biographical note on Joshua Moody (Harvard AB 1707), and a few additional annotations. Asterisks added next to the names of alumni who died after the Catalogue's publication.

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With sections on numeration, surveying, trigonometry and other topics, accompanied by diagrams and hand-colored illustrations.

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A collection of notebooks in which Hubbard recorded both legal and personal transactions in detail, including: writs, arrests, wills, boundary disputes, damages awarded in court cases over which he presided, various payments and expenses, etc. Also included are three notebooks kept by his nephew James Hubbard, who inherited Joshua Hubbard's farm; these primarily record the sale of cider and vinegar from his farm, costs of hired labor, and bank loans.

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This collection consists primarily of quarter bills and butler's bills from Charles Walker and Charles Walker, Jr.'s years as students at Harvard College, from 1785 to 1789 and from 1815-1816. It includes the following materials from Charles Walker: a form of admission (a printed form letter with manuscript annotations and signatures) from August 1785, quarter bills and butler's bills from 1785 to 1789, and occasional receipts of payment. The documents from Charles Walker, Jr. are less numerous, consisting solely of quarter bills from 1815 and 1816. The bills for father and son include annotations explaining the basis of additional or unusual charges, including fines for absence from lectures and prayers. The form used for the son's quarter bills, issued in 1815 and 1816, separate the amounts owed into the following categories: Steward and Commons, Sizings, Study and Cellar Rent, Instruction, Librarian, Natural History, Episcopal Church, Books, Catalogue and Commencement Dinner, Repairs, Sweepers, Assessments for delinquency in payment of Quarter Bills, Wood, and Fines. All of the bills are printed forms which were then filled out by hand, by either the steward or the butler, and issued to the students. Caleb Gannett was the College steward during both father and son's era. Joshua Paine, William Harris, and Thomas Adams served, successively, as butler during the father's era. Some of the butler's bills are signed by Roger Vose, a student who appears to have been employed by the butler in 1786 and 1787.