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This chapter reviews the fundamentals and achievements of ultrashort pulse generation and amplification in ytterbium-doped fibers. Compact and ultrastable passively mode-locked fiber oscillators represent an ideal seed source for high performance femtosecond fiber amplification systems, which have been scaled towards kW-level average power and pulse energies well above the mJ-level. These laser systems will have significant impact in numerous scientific and industrial applications.

Companies’ corporate social responsibility (CSR) activities respond to the increasing expectations of society. One of the three dimensions of sustainability, also known as the triple bottom line, is social sustainability. Compared to economic and environmental sustainability, the social dimension is often neglected by companies. Especially actors in the chemical industry are having a great social responsibility and are thus constantly monitored with regard to their activities and performance. Consequently, the firms need to care for their ocial sustainability in order to secure their license to operate. This study therefore aims at identifying the current state of social sustainability reporting within chemical companies in Germany. A data set of 14 CSR reports is tested regarding the use and fulfillment of the Global Reporting Initiative’s (GRI) guidelines and indicators regarding social aspects. The results clearly indicate that social sustainability reporting is handled quite diverse concerning structure and extent among the analyzed companies. The study concludes with recommendations of how to improve the comparability of social sustainability reporting for internal and external use.

We introduce and experimentally validate a pulse picking technique based on a travelling-wave-type acousto-optic modulator (AOM) having the AOM carrier frequency synchronized to the repetition rate of the original pulse train. As a consequence, the phase noise characteristic of the original pulse train is largely preserved, rendering this technique suitable for applications requiring carrier-envelope phase stabilization. In a proof-of-principle experiment, the 1030-nm spectral part of an 74-MHz, carrier-envelope phase stable Ti:sapphire oscillator is amplified and reduced in pulse repetition frequency by a factor of two, maintaining an unprecedentedly low carrier-envelope phase noise spectral density of below 68 mrad. Furthermore, a comparative analysis reveals that the pulse-picking-induced additional amplitude noise is minimized, when the AOM is operated under synchronicity. The proposed scheme is particularly suitable when the down-picked repetition rate is still in the multi-MHz-range, where Pockels cells cannot be applied due to piezoelectric ringing.

Submitted by Fabiano Jucá (fjuca@unicentro.br) on 2017-06-06T13:37:07Z No. of bitstreams: 1 JACQUELINE APARECIDA EIDAM HORST.pdf: 1908742 bytes, checksum: 547bf951451a9c89f2dce57a3fcdc5a3 (MD5) Made available in DSpace on 2017-06-06T13:37:07Z (GMT). No. of bitstreams: 1 JACQUELINE APARECIDA EIDAM HORST.pdf: 1908742 bytes, checksum: 547bf951451a9c89f2dce57a3fcdc5a3 (MD5) Previous issue date: 2015-08-28 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES The Alzheimer’s disease (AD) is a dementia of chronic and progressive nature that causes disturbance in the cognitive functions. Studies indicate that this pathology can be the result of oxidative stress generated in the organism of these individuals. Thus, the present study had as objective to compare the cognitive function, parameters of oxidative and hematological stress in patients with AD and the control group, registered in the Specialized Component of Pharmaceutical Assistance (CEAF), from Guarapuava municipality. 34 patients and 34 controls participated in the study, paring according to gender, age and, at least, one comorbidity. They received home visits for cognitive and socio-demographic evaluation, biochemical and hematological analyses. The cognitive evaluation was carried out using Mini-mental State Examination (MMSE). To evaluate the oxidative stress level, δ-ALA-D, GPx enzymes and vitamin C were dosed through colorimetric methods according to the methodology. For staging the disease, the scale Clinical Demential Rating was used. The sampling studied was comprised of 61.8% (n=21) of female individuals and 38.2% (n=13) of male individuals and their respective controls, with age average of 78.1 ± 8.9 years and median age equal to 80.0 ± 11.0 years. Concerning the physical activity, when comparing DA patients with the control group, there was a statistical difference, showing that the physical activity reduces as the DA level increases. In relation to the existent comorbities, there was no statistical difference when comparing DA patients and their controls. The cognitive function of most of the patients is reduced in the moderate and severe stages of the disease. As for the correlation between enzymes, when comparing patients with AD and the control group, the activity of the enzymes δ-ALA D and GPx have not showed significant difference in the early stage of the disease (CDR1) when dosed in erythrocytes. In the CDR2 and CDR3 stages, lower values were found in the patients with AD (p

In the light of frequent discussions about the correct performance of in vitro susceptibility testing and the interpretation of the results obtained, the aim of the present report is to summarize basic facts that may facilitate the understanding of this complex topic. For this, the terms "antimicrobial resistance", "ESBL", and "MRSA" are defined. Besides the statements on antimicrobial resistance, information on intrinsic and acquired resistance properties as well as basic rules for the correct performance of antimicrobial susceptibility testing in routine diagnostics are presented. Moreover, the two groups of interpretive criteria--clinical breakpoints and epidemiological cut-off values--including their applications are explained in detail. Furthermore, currently valid diagnostic procedures--as published by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and the Clinical and Laboratory Standards Institute (CLSI)--for the screening of ESBL-producing Enterobacteriaceae and MRSA as well as for the confirmation of suspicious isolates are presented and compared. Based on the information given, it becomes obvious that the correct performance of the diagnostic tests, which includes strict following the performance standards and the detailed information given therein, is an indispensable prerequisite for a standardized and harmonized in vitro susceptibility testing and--as a consequence--for the determination of valid and reliable susceptibility data in routine diagnostics. This is of utmost importance since the susceptibility data based on the use of clinical breakpoints often represent the basis for therapeutic interventions.

Conformational change in protein–ligand complexes is widely modeled, but the protein accommodation expected on binding a congeneric series of ligands has received less attention. Given their use in medicinal chemistry, there are surprisingly few substantial series of congeneric ligand complexes in the Protein Data Bank (PDB). Here we determine the structures of eight alkyl benzenes, in single-methylene increases from benzene to n-hexylbenzene, bound to an enclosed cavity in T4 lysozyme. The volume of the apo cavity suffices to accommodate benzene but, even with toluene, larger cavity conformations become observable in the electron density, and over the series two other major conformations are observed. These involve discrete changes in main-chain conformation, expanding the site; few continuous changes in the site are observed. In most structures, two discrete protein conformations are observed simultaneously, and energetic considerations suggest that these conformations are low in energy relative to the ground state. An analysis of 121 lysozyme cavity structures in the PDB finds that these three conformations dominate the previously determined structures, largely modeled in a single conformation. An investigation of the few congeneric series in the PDB suggests that discrete changes are common adaptations to a series of growing ligands. The discrete, but relatively few, conformational states observed here, and their energetic accessibility, may have implications for anticipating protein conformational change in ligand design.

ABSTRACT During the last decade, antimicrobial resistance in bacteria from food-producing animals has become a major research topic. In this review, different emerging resistance properties related to bacteria of food-producing animals are highlighted. These include: extended-spectrum β-lactamase-producing Enterobacteriaceae; carbapenemase-producing bacteria; bovine respiratory tract pathogens, such as Pasteurella multocida and Mannheimia haemolytica, which harbor the multiresistance mediating integrative and conjugative element ICEPmu1; Gram-positive and Gram-negative bacteria that carry the multiresistance gene cfr; and the occurrence of numerous novel antimicrobial resistance genes in livestock-associated methicillin-resistant Staphylococcus aureus. The emergence of the aforementioned resistance properties is mainly based on the exchange of mobile genetic elements that carry the respective resistance genes.

We demonstrate for the first time both spatial and temporal multiplexing in a scalable amplification scheme of ultrashort pulses. Using a division into two amplification channels and four pulse replicas high recombination efficiencies have been achieved at output energies far beyond the single-emitter damage threshold.

Over the last decade, the performance of femtosecond fiber laser systems has been rapidly improved. However, further improvements might be held back due to different physical limitations such as nonlinearities or optically induced damage. We demonstrate that with the coherent combination of four parallel fiber amplifiers record pulse energies and peak-powers of 5.7 mJ and 22 GW, respectively, could be achieved. These values could be realized with a chirped-pulse-amplification (CPA) laser system running at a repetition rate of 40 kHz and delivering a compressed average power of 230 W. A high combination efficiency of 89% was achieved demonstrating the scalability of the combining approach to a larger number of channels.

The active phase stabilization of spatially and temporally combined ultrashort pulses is investigated theoretically and experimentally. Particularly, considering a combining scheme applying 2 amplifier channels and 4 divided-pulse replicas a bistable behavior is observed. The reason is mutual influence of the optical error signals that is intrinsic to temporal polarization beam combining. A successful mitigation strategy is proposed and is analyzed theoretically and experimentally.

We demonstrate a pre-chirp managed Yb-doped fiber laser system that outputs 75 MHz, 130 W spectrally broadened pulses, which are compressed by a diffraction-grating pair to 60 fs with average powers as high as 100 W. Fine tuning the pulse chirp prior to amplification leads to high-quality compressed pulses. Detailed experiments and numerical simulation reveal that the optimum pre-chirp group-delay dispersion increases from negative to positive with increasing output power for rod-type high-power fiber amplifiers. The resulting laser parameters are suitable for extreme nonlinear optics applications such as frequency conversion in femtosecond enhancement cavities.

Made available in DSpace on 2017-07-21T14:13:03Z (GMT). No. of bitstreams: 1 Livia Eidam.pdf: 4492366 bytes, checksum: 6f8d83617df523059e48fdad789c558f (MD5) Previous issue date: 2015-02-12 Euphorbia umbellata (Pax) Bruyns, also known as janauba, belonging to the Euphorbiaceae family and it is the nomenclature accepts for Synadenium grantii Hook. f and Synadenium umbellatum Pax, which are synonymies according to some bibliographical references. It is popularly an employed species for the treatment of several cancer types, being the latex the vegetable part used for this purpose. In way to identify the species correctly, to contribute with the quality control and to correlate scientific studies of evaluation anticancer with the use etnopharmacologic, the proposed objectives were: to explore the morphoanatomy of E. umbellata; to evaluate the toxicity for the cells HeLa, HRT-18 and Jurkat and to proceed the phytochemistry investigation in the search of active substances. For the analysis macro and microscopic, leaves and stems of specimens designated as Synadenium grantii Hook. F (in Ponta Grossa) and Synadenium umbellatum Pax (in Goiânia) were previously fixed fastened in FAA solution. The material was sectioned by hand in the transverse and longitudinal directions. Astra blue and basic fuchsin were employed for staining. The citotoxicity of the latex was studied through biological rehearsals, with methodologies of mitochondrial reduction for MTT, internalization of VN for lysosomes; morphology for May Grunwald and Giemsa; membrane integrity for trypan blue; calculation of IC50; quantification of the content of DNA for DPA and propidium iodide; morphology for acridine orange and flow citometry. The phytochemistry, accomplished by accompaniment of biological rehearsals (biomonitored) results, it was done with the fraction Hex. The results ethnobotanical proved that the two specimens evaluated treat of the same plant which should be correctly denominated Euphorbia umbellata (Pax) Bruyns. These results elucidated the epicuticular wax, paracytic stomata and non-glandular trichomes; as well as laticifers; and they revealed chemical markers as the outstanding presence of the latex; composed lipophilic and phenolics compounds; starch and mucilage. The experimentation in vitro showed that the leukemic cells were firstly more responsive to the latex and later to the fraction Hex. IC50 calculated for the hexane fraction was of 1,87 μg/mL, value this that turns the composed phytocomplex of this fraction a promising antitumoral agents. After comparison with IC50 of non neolpasic cells, it was demonstrated IS of 5,98 and this corroborates the existence of selectivity action in relation to the analyzed cells. For flow citometry stop of cellular progression was verified, with substantial increase of the cells in phase G0/G1 and decrease of these in the phase G2/M. The phytochemistry study could contribute to the isolation of two identified triterpenes for techniques of nuclear magnetic resonance (RMN), being a pentacyclic denominated as germanicol acetate and for the first time isolated of this vegetable species and other tetracyclic designated euphol and already isolated of this Euphorbia umbellata (Pax) Bruyns. Euphorbia umbellata (Pax) Bruyns, conhecida também por janaúba, pertencente a família Euphorbiaceae e é a nomenclatura aceita para Synadenium grantii Hook. f e Synadenium umbellatum Pax, as quais são sinonímias segundo algumas referências bibliográficas. É uma espécie empregada popularmente para o tratamento de diversos tipos de câncer, sendo o látex a parte vegetal utilizada para este fim. De forma a identificar corretamente a espécie, contribuir com o controle de qualidade e correlacionar estudos científicos de avaliação anticâncer com o uso etnofarmacológico, os objetivos propostos foram: explorar a morfoanatomia de E. umbellata; avaliar a toxicidade para as células HeLa, HRT-18 e Jurkat e proceder a investigação fitoquímica na busca de substâncias ativas. Para a análise macro e microscópica, folhas e caules de espécimes designados como Synadenium grantii Hook. F (em Ponta Grossa) e Synadenium umbellatum Pax (em Goiania) foram previamente fixados em solução FAA. O material foi cortado à mão nos sentidos transversal e longitudinal. Azul de astra e fucsina básica foram utilizados para a coloração. A citotoxicidade do látex foi estudada através de ensaios biológicos, com metodologias de redução mitocondrial por MTT, internalização de VN por lisossomos; morfologia por May Grunwald e Giemsa; integridade de membrana por azul de tripan; cálculo de IC50; quantificação do conteúdo de DNA por DPA e iodeto de propídio; morfologia por alaranjado de acridina e citometria de fluxo. A fitoquímica, realizada por acompanhamento dos resultados dos ensaios biológicos (biomonitorado), foi feita com a fração Hex. Os resultados etnobotânicos comprovaram que as duas espécimes avaliadas tratam da mesma planta a qual deve ser corretamente denominada Euphorbia umbellata (Pax) Bruyns. Estes resultados elucidaram a existência de cêra epicuticular, estômatos paracíticos e tricomas tectores; assim como os tubos laticíferos; e revelaram marcadores químicos como a marcante presença do látex; compostos lipofílicos e fenólicos; amido e mucilagem. A xperimentação in vitro mostrou que as células leucêmicas foram primeiramente mais responsivas ao látex e posteriormente à fração Hex. O IC50 calculado para a fração hexânica foi de 1,87 μg/mL, valor este que torna o fitocomplexo constituidor desta fração um promissor agente antitumoral. Após comparação com o IC50 de células não neoplásicas, foi demonstrado IS de 5,98 e isso corrobora a existência de seletividade de ação em relação às células analisadas. Por citometria de fluxo verificou-se parada de progressão celular, com aumento substancial das células em fase G0/G1 e diminuição destas na fase G2/M. O estudo fitoquímico pôde contribuir para o isolamento de dois triterpenos identificados por técnicas de ressonância magnética nuclear (RMN), sendo um pentacíclico denominado como acetato de germanicol e pela primeira vez isolado desta espécie vegetal e outro tetracíclico designado eufol e já isolado de Euphorbia umbellata (Pax) Bruyns.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Sócio-Econômico, Programa de Pós-Graduação em Serviço Social, Florianópolis, 2015. Esta dissertação de mestrado tem como objetivo central analisar a questão agrária como constructo teórico-politico para o debate do problema da terra na atualidade. Para tanto, se estrutura em dois capítulos, dentro dos quais se realiza uma retomada dos principais clássicos que debatem a questão agrária, o desenvolvimento do capitalismo no campo e o campesinato. Esta retomada fornece subsídios para o debate atual. Na sequência partimos do resgaste histórico acerca da formação do Estado brasileiro, com a contextualização histórica da questão agrária para compreendermos sua gênese. Para a discussão da atualidade confrontamos os paradigmas agrários que encontram-se em disputa, sendo eles o Paradigma da Questão Agrária (PQA) e o Paradigma do Capitalismo Agrário (PCA). O primeiro defende a necessidade de se debater e implantar uma reforma agrária, enquanto o segundo postula que essa seja uma questão superada. A análise aqui pleiteada acredita na urgência de um posicionamento favorável a reforma agrária e que questione o modelo de produção vigente. Abstract : This master's dissertation aims to analyse the agrarian question as a theoretical-political construct to debate current land problems. In that case, this paper is divided into two chapters within which takes place a resumption of the major Russian classics that discuss the agrarian question, the development of capitalism in the countryside and the peasantry. This resumption provides subsidies to the current debate. Thereafter, an historical rescue about the formation of the Brazilian state was conducted, taking into account the historical context of the agrarian question in order to understand its genesis. For today's discussion agricultural paradigms that are in dispute were confronted, including the paradigm of Agrarian Question (PQA) and the Paradigm of Agrarian Capitalism (PCA). The first paradigm advocates the need to discuss and implement land reform, while the second one posits that this is an outdated issue. The analysis here pleaded believes in the urgency of a favourable position to land reform, as well as the need to question the current production model.

We demonstrate an alternative approach facilitating the use of a travelling-wave type acousto-optic modulator to pick pulses from a high-repetition-rate carrier-envelope phase stable pulse train where Pockels cells cannot be applied due to piezoelectric ringing.

We have performed a test run for laser cooling experiments with 12 C 3+ ion beams at an energy of 122 MeV/u at the CSRe with a pulsed laser. During this beamtime a lot of progress have been made. This was the first time we could successfully separate the 12 C 3+ ions and 16 O 4+ ions in the Schottky spectrum with the help of electron cooling. And our newly installed CPM detector worked well during the experiment. We tried to see effects from the interaction of the pulsed laser light with the stored 12 C 3+ ion beams, but no cooling effects could yet be observed.

We demonstrate a pre-chirp managed Yb-doped fiber laser system that outputs 75 MHz, 130Wspectrally broadened pulses, which are compressed by a diffraction-grating pair to 60 fs with average powers as high as 100 W. Fine tuning the pulse chirp prior to amplification leads to high-quality compressed pulses. Detailed experiments and numerical simulation reveal that the optimum pre-chirp group-delay dispersion increases from negative to positive with increasing output power for rod-type high-power fiber amplifiers. The resulting laser parameters are suitable for extreme nonlinear optics applications such as frequency conversion in femtosecond enhancement cavities.

During the last decades femtosecond lasers have proven their vast benefit in both scientific and technological tasks. Nevertheless, one laser feature bearing the tremendous potential for high-field applications, delivering extremely high peak and average powers simultaneously, is still not accessible. This is the performance regime several upcoming applications such as laser particle acceleration require, and therefore, challenge laser technology to the fullest. On the one hand, some state-of-the-art canonical bulk amplifier systems provide pulse peak powers in the range of multi-terawatt to petawatt. On the other hand, concepts for advanced solid-state-lasers, specifically thin disk, slab or fiber systems have shown their capability of emitting high average powers in the kilowatt range with a high wall-plug-efficiency while maintaining an excellent spatial and temporal quality of the output beam. In this article, a brief introduction to a concept for a compact laser system capable of simultaneously providing high peak and average powers all along with a high wall-plug efficiency will be given. The concept relies on the stacking of a pulse train emitted from a high-repetitive femtosecond laser system in a passive enhancement cavity, also referred to as temporal coherent combining. In this manner, the repetition rate is decreased in favor of a pulse energy enhancement by the same factor while the average power is almost preserved. The key challenge of this concept is a fast, purely reflective switching element that allows for the dumping of the enhanced pulse out of the cavity. Addressing this challenge could, for the first time, allow for the highly efficient extraction of joule-class pulses at megawatt average power levels and thus lead to a whole new area of applications for ultra-fast laser systems.

The coherent combination of ultra short laser pulses is a promising approach for scaling the average and peak power of ultrafast lasers. Fiber lasers and amplifiers are especially suited for this technique due to their simple singe-pass setups that can be easily parallelized. Here we propose the combination of the well-known approach of spatially separated amplification with the technique of divided-pulse amplification, i.e. an additionally performed temporally separated amplification. With the help of this multidimensional pulse stacking, laser systems come into reach capable of emitting 10's of joules of energy at multi-kW average powers that simultaneously employ a manageable number of fibers.

GSI Scientific Report 2014 - GSI Report 2015-1

Pre-chirp managed nonlinear amplification delivering high quality 60 fs pulses is compared to conventionally employed CPA. We present a compact rod-type system that outputs >100 W at 75 MHz.

GSI Scientific Report 2014 - GSI Report 2015-1

In the past the principle of Doppler laser cooling was investigated and verified in storage rings in the low energy regime. Within the FAIR project the laser cooling will be applied to high intensity and high energy beams for the first time. The laser cooling results in a further increase of the longitudinal phase space density and in non-Gaussian longitudinal beam profiles. In order to ensure stable operation and optimize the cooling process the interplay of the laser force and high intensity effects has to be studied numerically. This contribution will identify constrains of the cooling scheme for an efficient reduction of momentum spread. For high beam energies the scattering of photons has to be treated stochastically instead of using averaged forces. The modeling of the laser force in a particle in cell tracking code will be discussed., Proceedings of the 6th Int. Particle Accelerator Conf., IPAC2015, Richmond, VA, USA

The failure of the prison system has been aimed as one of the largest problems of the Brazilian repressive model. The convicts are correspondents to the jail with the purpose of rehabilitating them to the social conviviality, however, when coming back to the society, that individual will be more indifferent, unprepared, unsettled, and many times more uninhibited for the practice of another crimes. That glance reveals the presentation of a chess, of a public chain, or even of a state penitentiary. The purpose of the present work, though, it is to present another glance, based on researches accomplished in the state penitentiary of maximum safety of the city of Ponta Grossa, in the State of Paraná. It is a partnership between the public and private sector, denominated Double Responsibility or Coadministration being the administration of the prison and the education under the state government's responsibility and the installment of services that it includes internal safety, social attendance, doctor and psychological among other, to position of a private company. Keywords: Education of Young and Adults. Public politics. Private penitentiaries. Social recuperation. A falência do sistema carcerário tem sido apontada como uma das maiores mazelas do modelo repressivo brasileiro. Os condenados são enviados ao cárcere com o intuito de reabilitá-los ao convívio social, contudo, ao retornar à sociedade, esse indivíduo estará mais indiferente, despreparado, desambientado, e muitas vezes mais desenvolto para a prática de outros crimes. Esse olhar revela a apresentação de um xadrez, de uma cadeia pública, ou mesmo de uma penitenciária estadual. O propósito do presente trabalho, todavia, é apresentar um outro olhar, baseado em pesquisas realizadas na penitenciária estadual de segurança máxima da cidade de Ponta Grossa, no Estado do Paraná. Trata-se de uma parceria entre o setor público e privado, denominada Dupla Responsabilidade ou Co-Gestão ficando a administração do presídio e a educação sob a responsabilidade do governo estadual e a prestação de serviços que inclui segurança interna, assistência social, médica e psicológica entre outras, a cargo de uma empresa privada. Palavras-chave: Educação de Jovens e Adultos. Políticas públicas. Penitenciárias privadas. Ressocialização.

Although propofol is most commonly known for its general anesthetic properties, at subanesthetic doses, propofol has been effectively used to suppress seizures during refractory status epilepticus, a mechanism, in part, attributed to the inhibition of neuronal sodium channels. In this study, we have designed and synthesized two novel analogs of propofol, HS245 [2-(3-ethyl-4-hydroxy-5-isopropyl-phenyl)-3,3,3-trifluoro-2-hydroxy-propionamide] and HS357 [2-hydroxy-8-(4-hydroxy-3,5-diisopropyl-phenyl)-2-trifluoromethyl-octanoic acid amide], and determined their effects on sodium currents recorded from cultured hippocampal neurons. HS357 had greater affinity for the inactivated state of the sodium channel than propofol and HS245 (0.22 versus 0.74 and 1.2 microM, respectively) and exhibited the greatest ratio of affinity for the resting over the inactivated state. HS357 also demonstrated greater use-dependent block and delayed recovery from inactivation in comparison with propofol and HS245. Under current-clamp conditions, action potentials from hippocampal CA1 neurons in slices were evoked by current injection, or following perfusion with a zero Mg(2+)/7 mM K(+) artificial cerebrospinal fluid solution. Propofol and HS357 reduced the number of current-induced action potentials; however, HS357 caused a greater reduction in the number of spontaneous action potentials. Consistent with these electrophysiology studies, propofol and HS357 protected mice against acute seizures in the 6-Hz (22-mA) partial psychomotor model. Efficacious doses of propofol were associated with an impairment of motor coordination as assessed in the rotorod toxicity assay. In contrast, HS357 demonstrated a 2-fold greater protective index than propofol. Thus, propofol analogs represent an important structural class from which not only effective, but also safer, anti-convulsants may be developed.

Many pathogenic bacteria possess adhesive surface organelles (called pili), anchored to their outer membrane, which mediate the first step of infection by binding to host tissue. Pilus biogene- sis occurs via the ''chaperone-usher'' pathway: the usher, a large outer membrane protein, binds com- plexes of a periplasmic chaperone with pilus sub- units, unloads the subunits from the chaperone, and assembles them into the pilus, which is extruded into the extracellular space. Ushers comprise an N-termi- nal periplasmic domain, a large transmembrane b- barrel central domain, and a C-terminal periplasmic domain. Since structural data are available only for the N-terminal domain, we performed an in-depth bioinformatic analysis of bacterial ushers. Our analy- sis led us to the conclusion that the transmembrane b-barrel region of ushers contains a so far unrecog- nized soluble domain, the ''middle domain'', which possesses a b-sandwich fold. Two other bacterial b- sandwich domains, the TT0351 protein from Thermus thermophilus and the carbohydrate binding module CBM36 from Paenibacillus polymyxa ,a re possible distant relatives of the usher ''middle domain''. Sev- eral mutations reported to abolish in vivo pilus for- mation cluster in this region, underlining its func- tional importance. Proteins 2006;65:816-823. V C 2006 Wiley-Liss, Inc.

The purpose of this study was to evaluate the lifestyle of patients with Human Immunodeficiency Virus (HIV)and to associate it with CD4 positive T-lymphocytes counts. The convenience sample was composed by 111 subjects (68 males and 43 females, with mean age of 37 years). The data for lifestyle assessment (dietary habits, physical activity level, preventive health behavior, relationships and stress control) were assessed through interview. CD4 positive T-lymphocytes were obtained from patient’s hospital file. Descriptive statistics, one-way ANOVA, using Tukey post hoc test and the Chi-square test were performed. The results showed a mean CD4 positive Tlymphocytes of 345 cell.mm-3 and a median of 296 cell.mm-3. The majority of patients performed all routine tests and followed all medical recommendations (92,8%), used preservative during sexual intercourses (80,2%), tried to nurture friendship and were satisfied with their relationships (80,2%) and reserved daily time to relax (82%). Anundesirable lifestyle in the dietary habits and physical activity components was detected. The compliance to preventive health behaviors was significantly greater than the other (6.95 points). Statistically significant associations between stress control and CD4 positive T-lymphocytes equal or higher than 296 cell.mm-3 were observed (p RESUMO Este estudo pretendeu avaliar o estilo de vida de pacientes infectados pelo vírus da imunodeficiência humana (HIV) e associá-lo à contagem de linfócitos T CD4+. A amostra, selecionada por conveniência, foi constituídade 111 indivíduos (68 homens e 43 mulheres, com idade média de 37 anos). Os dados para avaliação do estilo de vida (hábitos alimentares, atividade física, comportamento preventivo, relacionamentos e controle do estresse), foram obtidos por meio de entrevista. Para a contagem do número de linfócitos T CD4+, considerou-se o resultado do último exame laboratorial apresentado na ficha do paciente. Foram realizadas análises descritivas, análise de variância (ANOVA) one-way, com o teste post hoc de Tukey e o teste qui–quadrado. Os resultados evidenciaramque a contagem média de linfócitos T CD4+ foi de 345 cel/mm3 e a mediana de 296 cel/mm3. A maioria dos pacientes realizava os exames de rotina e seguia as recomendações médicas (92,8%), usava preservativos durante as relações sexuais (80,2%), estava satisfeita com os relacionamentos (80,2%) e reservava tempo, todos os dias, para relaxar (82%). O perfil do estilo de vida, nos componentes hábitos alimentares e de atividade física habitual, foi classificado como insatisfatório. O comportamento preventivo foi a variável do estilo de vida com resultado médio significativamente superior aos demais (6,95 pontos). Foram observadas associações entre o controle do estresse, considerado satisfatório, e a contagem do número de linfócitos T CD4+ > 296 cel/mm3 (p0,05). Concluiu-se que os hábitos alimentares e o nível de atividade física habitual dos portadores do HIV foram considerados como insatisfatórios. Enfatiza-se a importância do controle do estresse para a contagem do número de linfócitos T CD4+ de pacientes infectados pelo HIV, sem desconsiderar a contribuição dos outros aspectos do estilo de vida.

We give a simplified proof of the Yoshida–Nicolaescu Theorem in the product case using the theory of partial signatures as in Giambo et al. (2004). The theorem gives the equality of the spectral flow of a family of first order self-adjoint differential operators defined on sections of a Hermitian vector bundle over a partitioned manifold and the Maslov index of the corresponding pair of Cauchy data spaces. No nondegeneracy assumption is made on the endpoints of the path of differential operators.

Type 1 pili are filamentous protein complexes that are anchored to the outer membrane of uropathogenic Escherichia coli and mediate bacterial adhesion to the surface of urinary epithelium cells. We review here the current status of structural and functional studies on the assembly of type 1 pili.

Background: There is increasing evidence that the Fas/Fas ligand (FasL) system is involved in tumor-mediated immune suppression. The purpose of this study was to investigate the effect of Fas (CD95) as well as FasL (CD95L) expression in primary malignant melanoma and melanoma metastases on overall survival (OS). Patients and Methods: 19 patients with metastatic malignant melanoma who were treated with different dacarbazine (DTIC)-based chemotherapy regimens were included in this study. From each patient, primary melanoma biopsies and biopsies from metastases were histologically evaluated. Immunohistology was performed with antibodies to Fas/CD95 and FasL/CD95L. Differences in OS were plotted using the Kaplan-Meier method and compared by the log rank test. Results: Fas/CD95 and FasL/CD95L expression was detected in 73.7 and 63.2% of primary melanomas, respectively. In metastases, expression of both Fas/CD95 (63.2%) and FasL/CD95L (47.4%) was markedly decreased. Presence of FasL/ CD95L expression in primary melanoma resulted in significantly (p = 0.024) prolonged OS compared with FasL/CD95L-negative high-risk primary melanomas. In contrast, loss of FasL/CD95L expression in melanoma metastases resected before chemotherapy was associated with significantly prolonged median survival (p = 0.0139). Conclusion: Presence of FasL/CD95L expression in primary malignant melanoma and the loss of FasL/ CD95L expression in metastases seem to be positive prognostic factors.

We combine high-finesse optical resonators and spatial-spectral interferometry to a highly phase-sensitive investigation technique for nonlinear light-matter interactions. We experimentally validate an ab initio model for the nonlinear response of a resonator housing a gas target, permitting the global optimization of intracavity conversion processes like high-order harmonic generation. We predict the feasibility of driving intracavity high-order harmonic generation far beyond intensity limitations observed in state-of-the-art systems by exploiting the intracavity nonlinearity to compress the pulses in time.

Chemical probes that form a covalent bond with a protein target often show enhanced selectivity, potency and utility for biological studies. Despite these advantages, protein-reactive compounds are usually avoided in high-throughput screening campaigns. He

Adhesive type 1 pili from uropathogenic Escherichia coli are filamentous protein complexes that are attached to the assembly platform FimD in the outer membrane. During pilus assembly, FimD binds complexes between the chaperone FimC and type 1 pilus subunits in the periplasm and mediates subunit translocation to the cell surface. Here we report nuclear magnetic resonance and X-ray protein structures of the N-terminal substrate recognition domain of FimD (FimD(N)) before and after binding of a chaperone-subunit complex. FimD(N) consists of a flexible N-terminal segment of 24 residues, a structured core with a novel fold, and a C-terminal hinge segment. In the ternary complex, residues 1-24 of FimD(N) specifically interact with both FimC and the subunit, acting as a sensor for loaded FimC molecules. Together with in vivo complementation studies, we show how this mechanism enables recognition and discrimination of different chaperone-subunit complexes by bacterial pilus assembly platforms.