From Davydov solitons to decoherence-free subspaces: self-consistent propagation of coherent-product states

The self-consistent propagation of generalized $D_{1}$ [coherent-product] states and of a class of gaussian density matrix generalizations is examined, at both zero and finite-temperature, for arbitrary interactions between the localized lattice (electronic or vibronic) excitations and the phonon modes. It is shown that in all legitimate cases, the evolution of $D_{1}$ states reduces to the disentangled evolution of the component $D_{2}$ states. The self-consistency conditions for the latter amount to conditions for decoherence-free propagation, which complement the $D_{2}$ Davydov soliton equations in such a way as to lift the nonlinearity of the evolution for the on-site degrees of freedom. Although it cannot support Davydov solitons, the coherent-product ansatz does provide a wide class of exact density-matrix solutions for the joint evolution of the lattice and phonon bath in compatible systems. Included are solutions for initial states given as a product of a [largely arbitrary] lattice state and a thermal equilibrium state of the phonons. It is also shown that external pumping can produce self-consistent Frohlich-like effects. A few sample cases of coherent, albeit not solitonic, propagation are briefly discussed.Comment: revtex3, latex2e; 22 pages, no figs.; to appear in Phys.Rev.E (Nov.2001

Different regulation of haloperoxidation during agar oligosaccharide-activated defence mechanisms in two related red algae

The related red seaweeds Gracilaria sp. from the eastern Mediterranean and Gracilaria chilensis from Chile were similar in their enzymatic inventory for halogenation. In both species, halogenation was dependent upon H(2)O(2) and thus driven by haloperoxidases. These could be inhibited with phosphate and reversibly inhibited with azide and were therefore apparently dependent upon vanadate. Both species generated in the first line bromoform and other brominated halocarbons. Gel electrophoresis under non-denaturating conditions demonstrated that both species expressed halogenating peroxidases. Elicitation of Gracilaria sp. with agar oligosaccharides resulted in marked increases in bromination, iodination, and chlorination. Production rates of volatile halocarbons and phenol red bromination both increased by a factor of eight, presumably due to increased availability for haloperoxidases of H(2)O(2) during the oxidative burst response. Elicitation of Gracilaria sp. also triggered a release of bromide ions through DIDS-sensitive anion channels, which allowed for some bromination in bromide-free medium. However, this effect was relatively limited. By contrast, agar oligosaccharide oxidation in G. chilensis did not increase halogenation. Obviously, agar oligosaccharide oxidation does not provide sufficient amounts of hypohalous acids for such increases, because it does not deliver H(2)O(2) at the active site of vanadium-dependent haloperoxidases. These results correlate with earlier findings that the agar oligosaccharide-elicited oxidative burst controls microorganisms while agar oligosaccharide oxidation does not

The mediterranean biotypes of Tylenchulus semipenetrans in Spanish citrus orchards

Les capacités de reproduction de quatorze populations du nématode des citrus (#Tylenchulus semipenetrans$) collectées dans la principale zone de citriculture de l'Espagne ont été comparées sur oranger amer et citrange Carrizo. Toutes les populations ont été identifiées comme appartenant au biotype méditerranéen. La capacité de reproduction varie considérablement en fonction des populations. Le pouvoir infestant et le taux de reproduction des populations collectées dans la rhizosphère des porte-greffes citranges Troyer ou Carrizo sont plus élevés (P supérieur ou égal à 0,05) que ceux des populations collectées sur oranger amer. (Résumé d'auteur

Conversa amb Th. S. Popkewitz: els ensenyants i la reforma de la formació del professorat als EUA, professionalització i poder

La meva hipòtesi és que els supòsits socials i epistemològics que s'han incorporat a les reformes nord-americanes de formació del profes.sorat tendeixen a mistificar la complexitat social i política de I'escolarització i a descontextualitzar les profundes qüestions sobre el poder i el coneixement a I'ensenyament. Les regles, els programes de recerca, els informes de les administracions estan expressats en els termes més humanistes i progressistes possibles. Pretenen portar-nos a tots la democracia, generar un creixement económic i una renovació cultural, i també promoure el desenvolupament individual. Peró a través del recorregut deis somnis i la retórica progressista hom pot observar la creació de tecnologies que s'internalitzen i organitzen la vida quotidiana, Ilurs esperances i anhels. Th .. S. Popkewitz (1993

Identificação do gene pccB A partir da varredura de uma biblioteca genômica de Corynebacterium pseudotuberculosis visando uma vacina contra linfadenite caseosa.

Corynebacterium pseudotuberculosis é o agente etiológico da linfadenite caseosa (LC), que acomete principalmente ovinos e caprinos. Esta doença é causadora de grandes problemas na ovinocaprinocultura. Diversas pesquisas tem sido realizadas na busca de uma vacina eficaz contra a LC. Estudos recentes utilizando um gene reporter em C. pseudotuberculosis, identificou a expressão do gene pccB (cadeia β da propionil CoA carboxilase) em macrófagos, indicando um possível envolvimento na virulência deste patógeno e um bom antígeno a ser explorado no desenvolvimento de uma nova estratégia vacinal. Como a sequência deste gene ainda não está disponível em banco de dados, o objetivo deste trabalho foi realizar varredura em uma biblioteca genômica de C. pseudotuberculosis para identificação completa da sequência do gene pccB. Uma sonda foi gerada a partir de um fragmento parcial do gene pccB marcado com [α32P]dCTP. A biblioteca genômica foi plaqueada em placas de lise para obter 2X103 pfu/placa e em seguida transferida para membranas de nylon previamente tratadas com soluções desnaturante, neutralizante e de pré-hibridização, a fim de, posteriormente, reagir com a sonda radioativa seguido da exposição das membranas a um filme de raio X. Dois clones positivos foram isolados e utilizados como template em reação de PCR, utilizando primers específicos da biblioteca genômica, gerando produtos de 3 Kb que foram sequenciados e analisados por BlastX, verificando-se 82% de identidade com o gene pccB2 de C. diphtheriae. Acreditando que haja sintenia entre as duas espécies mencionadas, foram desenhados primers com genes que flanqueiam o gene pccB2 de C. diphtheriae. Esses foram utilizados como iniciadores em reação de PCR, tendo como molde o DNA genômico de C. Pseudotuberculosis, gerando um fragmento de 2,1 Kb que foi clonado no vetor pGEM-T easy, sequenciado e analisado por BlastX. Resultados preliminares indicam que novos primers precisam ser desenhados para concluir a sequência deste gene

Análise da variabilidade intra-espécie dos genes pld e rpoB de Corynebacterium pseudotuberculosis por meio de marcadores PCR-RFLP.

Corynebacterium pseudotuberculosis é o agente etiológico da linfadenite caseosa em ovinos e caprinos, uma doença infectocontagiosa crônica caracterizada por abscessos em linfonodos superficiais ou internos. Os animais acometidos podem apresentar lesões internas ou externas, o que representa perdas econômicas graves na caprinovinocultura, como o comprometimento da produção de lã em ovinos, deficiência reprodutiva, condenação da carne ou morte do animal. Uma vez estabelecida a infecção no rebanho, torna-se difícil sua erradicação. Com o objetivo de avaliar a variabilidade genética intra-espécie em C. pseudotuberculosis, 31 isolados provenientes de seis municípios do Estado de Pernambuco, sendo 23 de caprinos e oito de ovinos, tiveram os seus DNAs genômicos extraídos e analisados por reação em cadeia da polimerase e análise de polimorfismos por tamanho de fragmentos de restrição (PCR-RFLP). Os locis escolhidos foram os genes pld e rpoB, cujas seqüências dos oligonucleotídeos amplificaram fragmentos de 924 e 447 pares de bases (pb), respectivamente. Os produtos da amplificação foram digeridos com as enzimas Pst I e Msp I (gene pld) e HpyCh4 IV e Msp I (gene rpoB). Os fragmentos de restrição foram corridos em gel de poliacrilamida a 15%, os quais foram corados com brometo de etídeo. Para o gene pld, digerido com a enzima Pst I, foram obtidos fragmentos de 566, 195, 91 e 72 pb; e com a enzima Msp I, fragmentos de 395, 369, 108 e 52 pb. O gene rpoB digerido com a enzima HpyCh4 IV apresentou fragmentos de 235, 126 e 86 pb; e com a enzima Msp I apresentou fragmentos de 222, 93, 78 e 54 pb. O padrão de bandas obtido para os 31 isolados de C. pseudotuberculosis, analisados neste estudo, foi monomórfico, não havendo, portanto, polimorfismo entre os diferentes isolados, independentes da espécie hospedeira ou da área geográfica estudada, o que corrobora com o padrão homogêneo da infecção para a região.bitstream/CNPGC-2009-09/12402/1/DOC167.pd

Non-profit Fundraising Event Plan

Presented to the Faculty of the University of Alaska Anchorage in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCEThis project conducts applied research through a fundraising project for the Alaska Institute for Justice (AIJ). Founded in 2005, AIJ is a non-profit agency that provides legal services to immigrants and refugees. It represents people fleeing persecution in their home countries as well as domestic violence and human trafficking crime victims. It provides the only low-fee services of its kind in the state, helping community members who are often isolated, low-income, vulnerable to abuse, and with few other avenues to gain legal representation. AIJ also operates a statewide language interpreter center that provides immigrant and refugee expertise to numerous state and federal agencies dedicated to health care, social services, and law enforcement. The AIJ fundraising project will analyze the effectiveness of project management tools used during planning and execution of a new fundraiser event plan. The project will also apply literature reviews and interviews to assess AIJ’s and other mature Anchorage area non-profits’ familiarity with project management tools and to provide recommended project management tools to improve organizational efficiency. The project’s products include an event plan that consists of immigrant speaker performances and a silent auction. The deliverables are an event checklist and continuity documents to help AIJ repeat this fundraising event annually. In addition, the project will deliver publicity tasks designed to increase awareness of the AIJ mission, expand AIJ’s donor base, and increase its annual donor revenue.Table of Contents / List of Exhibits / List of Appendices / Abstract / Introduction / Research Methodology / Literature Review Results / Research Analysis Research Results / Conclusions / Recommendations for Further Research / Reference

Placental syncytiotrophoblast constitutes a major barrier to vertical transmission of Listeria monocytogenes.

Listeria monocytogenes is an important cause of maternal-fetal infections and serves as a model organism to study these important but poorly understood events. L. monocytogenes can infect non-phagocytic cells by two means: direct invasion and cell-to-cell spread. The relative contribution of each method to placental infection is controversial, as is the anatomical site of invasion. Here, we report for the first time the use of first trimester placental organ cultures to quantitatively analyze L. monocytogenes infection of the human placenta. Contrary to previous reports, we found that the syncytiotrophoblast, which constitutes most of the placental surface and is bathed in maternal blood, was highly resistant to L. monocytogenes infection by either internalin-mediated invasion or cell-to-cell spread. Instead, extravillous cytotrophoblasts-which anchor the placenta in the decidua (uterine lining) and abundantly express E-cadherin-served as the primary portal of entry for L. monocytogenes from both extracellular and intracellular compartments. Subsequent bacterial dissemination to the villous stroma, where fetal capillaries are found, was hampered by further cellular and histological barriers. Our study suggests the placenta has evolved multiple mechanisms to resist pathogen infection, especially from maternal blood. These findings provide a novel explanation why almost all placental pathogens have intracellular life cycles: they may need maternal cells to reach the decidua and infect the placenta

Two-vibron bound states in alpha-helix proteins : the interplay between the intramolecular anharmonicity and the strong vibron-phonon coupling

The influence of the intramolecular anharmonicity and the strong vibron-phonon coupling on the two-vibron dynamics in an $\alpha$-helix protein is studied within a modified Davydov model. The intramolecular anharmonicity of each amide-I vibration is considered and the vibron dynamics is described according to the small polaron approach. A unitary transformation is performed to remove the intramolecular anharmonicity and a modified Lang-Firsov transformation is applied to renormalize the vibron-phonon interaction. Then, a mean field procedure is realized to obtain the dressed anharmonic vibron Hamiltonian. It is shown that the anharmonicity modifies the vibron-phonon interaction which results in an enhancement of the dressing effect. In addition, both the anharmonicity and the dressing favor the occurrence of two different bound states which the properties strongly depend on the interplay between the anharmonicity and the dressing. Such a dependence was summarized in a phase diagram which characterizes the number and the nature of the bound states as a function of the relevant parameters of the problem. For a significant anharmonicity, the low frequency bound states describe two vibrons trapped onto the same amide-I vibration whereas the high frequency bound states refer to the trapping of the two vibrons onto nearest neighbor amide-I vibrations.Comment: may 2003 submitted to Phys. Rev.

Comparação genotípica de isolados de Corynebacterium pseudotuberculosis de caprinos e ovinos do sertão de Pernambuco.

Objetivou-se com este estudo comparar genotipicamente 35 isolados de Corynebacterium pseudotuberculosis recuperados de conteúdo de abscessos de caprinos e ovinos com linfadenite caseosa, procedentes de cinco municípios localizados no Sertão de Pernambuco, Brasil. Utilizou-se a técnica de fingerprint RFLP-PCR com as enzimas de restrição Hpy-Ch4 e Msp 1 aplicada ao gene pld. Não houve diferença nos padrões de fragmentos de bandas entre os isolados, independente da espécie hospedeira ou da área geográfica estudada, definindo-se um padrão genotípico homogêneo de C. pseudotuberculosis responsável por abscessos superficiais na região