902 resultados para Simulation with multiple Consumers Profiles
Resumo:
"Slow Fashion" attempts to offset the demand for fast fashion and mass production (Fletcher, 2007). Consumers' response to sustainability-based practices is a limited discourse and studies for slow fashion concept are scarce. This study thus aims to enlighten the subject of how slow fashion concept could improve local economies and how Spanish consumers respond to such initiatives. This paper is based on an exploratory qualitative research for which focus group interviews including three group discussions with Spanish consumers were held. The data was examined by constant comparison analysis to present consumer insights. Moreover, a case study was conducted with a Spanish apparel brand. Saint Brissant was chosen since it manufactures in Spain to (i) ensure its products? high quality and (ii) to empower Spanish economy. This paper provides empirical insights. Even though local manufacturing was perceived to have a higher quality, Spanish consumers? behavioural intentions of using local brands were not high.Self-interest, mainly price and design, was recorded as the most influential purchase criteria. Furthermore, Saint Brissant case demonstrated that local manufacturing could boost local economies by creating workforce. However, governmental subsidies should be rearranged and consumers? perceptions should be improved to support local manufacturers in Spain.
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This study shows the air flow behavior through the geometry of a freight truck inside a AF6109 wind tunnel with the purpose to predict the speed, pressure and turbulence fields made by the air flow, to decrease the aerodynamic resistance, to calculate the dragging coefficient, to evaluate the aerodynamics of the geometry of the prototype using the CFD technique and to compare the results of the simulation with the results obtained experimentally with the “PETER 739 HAULER” scaled freight truck model located on the floor of the test chamber. The Geometry went through a numerical simulation process using the CFX 5,7. The obtained results showed the behavior of the air flow through the test chamber, and also it showed the variations of speed and pressure at the exit of the chamber and the calculations of the coefficient and the dragging force on the geometry of the freight truck. The evaluation of the aerodynamics showed that the aerodynamic deflector is a device that helped the reduction the dragging produced in a significant way by the air. Furthermore, the dragging coefficient and force on the prototype freight truck could be estimated establishing an incomplete similarity.
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N-type Ca2+ channels mediate Ca2+ influx, which initiates fast exocytosis of neurotransmitters at synapses, and they interact directly with the SNARE proteins syntaxin and SNAP-25 (synaptosome-associated protein of 25 kDa) through a synaptic protein interaction (synprint) site in the intracellular loop connecting domains II and III of their α1B subunits. Introduction of peptides containing the synprint site into presynaptic neurons reversibly inhibits synaptic transmission, confirming the importance of interactions with this site in synaptic transmission. Here we report a direct interaction of the synprint peptide from N-type Ca2+ channels with synaptotagmin I, an important Ca2+ sensor for exocytosis, as measured by an affinity-chromatography binding assay and a solid-phase immunoassay. This interaction is mediated by the second C2 domain (C2B) of synaptotagmin I, but is not regulated by Ca2+. Using both immobilized recombinant proteins and native presynaptic membrane proteins, we found that the synprint peptide and synaptotagmin competitively interact with syntaxin. This interaction is Ca2+-dependent because of the Ca2+ dependence of the interactions between syntaxin and these two proteins. These results provide a molecular basis for a physical link between Ca2+ channels and synaptotagmin, and suggest that N-type Ca2+ channels may undergo a complex series of Ca2+-dependent interactions with multiple presynaptic proteins during neurotransmission.
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Arc repressor mutants containing from three to 15 multiple-alanine substitutions have spectral properties expected for native Arc proteins, form heterodimers with wild-type Arc, denature cooperatively with Tms equal to or greater than wild type, and, in some cases, fold as much as 30-fold faster and unfold as much as 50-fold slower than wild type. Two of the mutants, containing a total of 14 different substitutions, also footprint operator DNA in vitro. The stability of some of the proteins with multiple-alanine mutations is significantly greater than that predicted from the sum of the single substitutions, suggesting that a subset of the wild-type residues in Arc may interact in an unfavorable fashion. Overall, these results show that almost half of the residues in Arc can be replaced by alanine en masse without compromising the ability of this small, homodimeric protein to fold into a stable, native-like structure.
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Classical familial adenomatous polyposis (FAP) is a high-penetrance autosomal dominant disease that predisposes to hundreds or thousands of colorectal adenomas and carcinoma and that results from truncating mutations in the APC gene. A variant of FAP is attenuated adenomatous polyposis coli, which results from germ-line mutations in the 5′ and 3′ regions of the APC gene. Attenuated adenomatous polyposis coli patients have “multiple” colorectal adenomas (typically fewer than 100) without the florid phenotype of classical FAP. Another group of patients with multiple adenomas has no mutations in the APC gene, and their phenotype probably results from variation at a locus, or loci, elsewhere in the genome. Recently, however, a missense variant of APC (I1307K) was described that confers an increased risk of colorectal tumors, including multiple adenomas, in Ashkenazim. We have studied a set of 164 patients with multiple colorectal adenomas and/or carcinoma and analyzed codons 1263–1377 (exon 15G) of the APC gene for germ-line variants. Three patients with the I1307K allele were detected, each of Ashkenazi descent. Four patients had a germ-line E1317Q missense variant of APC that was not present in controls; one of these individuals had an unusually large number of metaplastic polyps of the colorectum. There is increasing evidence that there exist germ-line variants of the APC gene that predispose to the development of multiple colorectal adenomas and carcinoma, but without the florid phenotype of classical FAP, and possibly with importance for colorectal cancer risk in the general population.
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Residual structure in the denatured state of a protein may contain clues about the early events in folding. We have simulated by molecular dynamics the denatured state of barnase, which has been studied by NMR spectroscopy. An ensemble of 104 structures was generated after 2 ns of unfolding and following for a further 2 ns. The ensemble was heterogeneous, but there was nonrandom, residual structure with persistent interactions. Helical structure in the C-terminal portion of helix α1 (residues 13–17) and in helix α2 as well as a turn and nonnative hydrophobic clustering between β3 and β4 were observed, consistent with NMR data. In addition, there were tertiary contacts between residues in α1 and the C-terminal portion of the β-sheet. The simulated structures allow the rudimentary NMR data to be fleshed out. The consistency between simulation and experiment inspires confidence in the methods. A description of the folding pathway of barnase from the denatured to the native state can be constructed by combining the simulation with experimental data from φ value analysis and NMR.
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Electron microscopy of human skin fibroblasts syringe-loaded with human immunodeficiency virus type 1 protease (HIV-1 PR) revealed several effects on nuclear architecture. The most dramatic is a change from a spherical nuclear morphology to one with multiple lobes or deep invaginations. The nuclear matrix collapses or remains only as a peripheral rudiment, with individual elements thicker than in control cells. Chromatin organization and distribution is also perturbed. Attempts to identify a major nuclear protein whose cleavage by the protease might be responsible for these alterations were unsuccessful. Similar changes were observed in SW 13 T3 M [vimentin+] cells, whereas no changes were observed in SW 13 [vimentin−] cells after microinjection of protease. Treatment of SW 13 [vimentin−] cells, preinjected with vimentin to establish an intermediate filament network, with HIV-1 PR resulted in alterations in chromatin staining and distribution, but not in nuclear shape. These same changes were produced in SW 13 [vimentin−] cells after the injection of a mixture of vimentin peptides, produced by the cleavage of vimentin to completion by HIV-1 PR in vitro. Similar experiments with 16 purified peptides derived from wild-type or mutant vimentin proteins and five synthetic peptides demonstrated that exclusively N-terminal peptides were capable of altering chromatin distribution. Furthermore, two separate regions of the N-terminal head domain are primarily responsible for perturbing nuclear architecture. The ability of HIV-1 to affect nuclear organization via the liberation of vimentin peptides may play an important role in HIV-1-associated cytopathogenesis and carcinogenesis.
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Dendritic spines are sites of the vast majority of excitatory synaptic input to hippocampal CA1 pyramidal cells. Estrogen has been shown to increase the density of dendritic spines on CA1 pyramidal cell dendrites in adult female rats. In parallel with increased spine density, estrogen has been shown also to increase the number of spine synapses formed with multiple synapse boutons (MSBs). These findings suggest that estrogen-induced dendritic spines form synaptic contacts with preexisting presynaptic boutons, transforming some previously single synapse boutons (SSBs) into MSBs. The goal of the current study was to determine whether estrogen-induced MSBs form multiple synapses with the same or different postsynaptic cells. To quantify same-cell vs. different-cell MSBs, we filled individual CA1 pyramidal cells with biocytin and serially reconstructed dendrites and dendritic spines of the labeled cells, as well as presynaptic boutons in synaptic contact with labeled and unlabeled (i.e., different-cell) spines. We found that the overwhelming majority of MSBs in estrogen-treated animals form synapses with more than one postsynaptic cell. Thus, in addition to increasing the density of excitatory synaptic input to individual CA1 pyramidal cells, estrogen also increases the divergence of input from individual presynaptic boutons to multiple postsynaptic CA1 pyramidal cells. These findings suggest the formation of new synaptic connections between previously unconnected hippocampal neurons.
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The release of vast quantities of DNA sequence data by large-scale genome and expressed sequence tag (EST) projects underlines the necessity for the development of efficient and inexpensive ways to link sequence databases with temporal and spatial expression profiles. Here we demonstrate the power of linking cDNA sequence data (including EST sequences) with transcript profiles revealed by cDNA-AFLP, a highly reproducible differential display method based on restriction enzyme digests and selective amplification under high stringency conditions. We have developed a computer program (GenEST) that predicts the sizes of virtual transcript-derived fragments (TDFs) of in silico-digested cDNA sequences retrieved from databases. The vast majority of the resulting virtual TDFs could be traced back among the thousands of TDFs displayed on cDNA-AFLP gels. Sequencing of the corresponding bands excised from cDNA-AFLP gels revealed no inconsistencies. As a consequence, cDNA sequence databases can be screened very efficiently to identify genes with relevant expression profiles. The other way round, it is possible to switch from cDNA-AFLP gels to sequences in the databases. Using the restriction enzyme recognition sites, the primer extensions and the estimated TDF size as identifiers, the DNA sequence(s) corresponding to a TDF with an interesting expression pattern can be identified. In this paper we show examples in both directions by analyzing the plant parasitic nematode Globodera rostochiensis. Various novel pathogenicity factors were identified by combining ESTs from the infective stage juveniles with expression profiles of ∼4000 genes in five developmental stages produced by cDNA-AFLP.
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Studies of the temperature-sensitive cdc37-1 mutant of Saccharomyces cerevisiae suggest that Cdc37 is required for passage through the G1 phase of the cell cycle, but its precise function is not known. We have investigated the role of Cdc37 in the regulation of the cyclin-dependent protein kinase Cdc28. We find that G1 arrest in the cdc37-1 mutant is accompanied by a decrease in the Cdc28 activity associated with the G1 cyclin Cln2. This defect appears to be caused by a decrease in the binding of Cdc28 and Cln2. cdc37-1 mutants also exhibit a defect in the binding and activation of Cdc28 by the mitotic cyclin Clb2. Thus Cdc37 may be a regulator that is required for the association of Cdc28 with multiple cyclins.
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Introdução: A microbiota intestinal possui grande diversidade de bactérias, predominantemente dos filos Bacteroidetes e Firmicutes, com múltiplas funções. A alimentação pode alterar sua composição e função. Alto teor de gordura saturada altera a permeabilidade intestinal, eleva os lipopolissacarídeos e predispõe à inflamação subclínica crônica. Dieta rica em fibras, como a vegetariana, induz elevação de ácidos graxos de cadeia curta e benefícios metabólicos. Objetivos: Para analisar a composição da microbiota intestinal de adventistas com diferentes hábitos alimentares e associá-los à inflamação subclínica e resistência à insulina, esta tese incluiu: 1) revisão dos mecanismos que associam a alimentação à microbiota intestinal e ao risco cardiometabólico; 2) verificação da composição da microbiota intestinal segundo diferentes hábitos alimentares e de associações com biomarcadores de doenças cardiometabólicas; 3) avaliação da associação entre a abundância de Akkermansia muciniphila e o metabolismo da glicose; 4) análise da presença de enterótipos e de associações com características clínicas. Métodos: Este estudo transversal incluiu 295 adventistas estratificados segundo hábitos alimentares (vegetariano estrito, ovo-lacto-vegetariano e onívoro). Foram avaliadas associações com dados clínicos, bioquímicos e inflamatórios. O perfil da microbiota foi obtido por sequenciamento do gene 16S rRNA (Illumina® Miseq). Resultados: 1) Há evidências de que as relações entre dieta, inflamação, resistência à insulina e risco cardiometabólico são em parte mediadas pela composição da microbiota intestinal. 2) Vegetarianos apresentaram melhor perfil clínico quando comparados aos onívoros. Confirmou-se maior abundância de Firmicutes e Bacteroidetes, que não diferiram segundo a adiposidade corporal. Entretanto, vegetarianos estritos apresentaram mais Bacteroidetes, menos Firmicutes e maior abundância do gênero Prevotella quando comparados aos outros dois grupos de hábitos alimentares. Entre os ovo-lactovegetarianos verificou-se maior proporção de Firmicutes especialmente do gênero Faecalibacterium. Nos onívoros, houve super-representação do filo Proteobacteria (Succinivibrio e Halomonas) comparados aos vegetarianos. 3) Indivíduos normoglicêmicos apresentaram maior abundância de Akkermansia muciniphila que aqueles com glicemia alterada. A abundância desta bactéria correlacionou-se inversamente à glicemia e hemoglobina glicosilada. 4) Foram identificados três enterótipos (Bacteroides, Prevotella e Ruminococcaceae), similares àqueles previamente descritos. As concentrações de LDL-C foram menores no enterótipo 2, no qual houve maior frequência de vegetarianos estritos. Discussão: 1) Conhecimentos sobre participação da microbiota na fisiopatologia de doenças poderão reverter em estratégias para manipulá-la para promover saúde. 2) Apoia-se a hipótese de que hábitos alimentares se associam favorável ou desfavoravelmente a características metabólicas e inflamatórias do hospedeiro via alterações na composição da microbiota intestinal. Sugerimos que a exposição a alimentos de origem animal possa impactar negativamente nas proporções de comunidades bacterianas. 3) Sugerimos que a abundância da Akkermansia muciniphila possa participar do metabolismo da glicose. 4) Reforçamos que a existência de três enterótipos não deva ser específica de certas populações/continentes. Apesar de desconhecido o significado biológico destes agrupamentos, as correlações com o perfil lipídico podem sugerir sua utilidade na avaliação do risco cardiometabólico. Conclusões: Nossos achados fortalecem a ideia de que a composição da microbiota intestinal se altera mediante diferentes hábitos alimentares, que, por sua vez, estão associados a alterações nos perfis metabólicos e inflamatórios. Estudos prospectivos deverão investigar o potencial da dieta na prevenção de distúrbios cardiometabólicos mediados pela microbiota.
Resumo:
A inclusão de óleos vegetais na dieta de bovinos tem sido utilizada para aumentar a densidade energética da dieta, melhorar a eficiência alimentar, além de produzir carnes com a composição de ácidos graxos mais favorável à saúde humana. Objetivou-se estudar os efeitos da inclusão de óleos de soja, girassol e linhaça na dieta de bovinos, sobre o desempenho, características quantitativas de carcaça e qualitativas da carne, perfil de ácidos graxos, oxidação lipídica e formação de compostos oxidados do colesterol. Foram confinados 96 bovinos Nelore, castrados, com aproximadamente 380 kg ± 34 kg de peso inicial e idade média de 20 meses. As dietas foram compostas de 79% de concentrado e 21% de volumoso (silagem de milho) e incluídos os óleos de soja, girassol e linhaça. Os animais foram pesados e avaliadas as características de carcaça por ultrassonografia nos dias 0, 28, 56 e 81 de confinamento. Nos dias zero e 81 dias de confinamento foi coletado sangue dos bovinos para avaliação do LDL-colesterol, HDL-colesterol, VLDL-colesterol e triacilgliceróis. Ao final de 81 dias de confinamento, os animais foram abatidos e foi avaliado o pH (uma e 48 horas após o abate) e foram retiradas amostras do músculo longissimus. Foi avaliado a cor, força de cisalhamento (FC) e perdas por cocção (PPC) em carnes não maturadas e maturadas por 14 dias. Duas amostras do longissimus foram expostas por um e três dias em condições semelhantes ao varejo. Nas carnes expostas por um dia foi avaliado a cor e o pH. Nas amostras expostas por três dias foi avaliado além da cor e pH, o perfil de ácidos graxos, TBARS, colesterol e a presença do 7-cetocolesterol. Foi realizada ainda a análise sensorial e determinado a quantidade de lipídios totais das carnes. A estabilidade oxidativa dos óleos utilizados na dieta também foi avaliada. O experimento foi conduzido em delineamento de blocos casualizados, sendo o peso inicial o bloco. O desempenho e as características de carcaça avaliadas por ultrassonografia não foram influenciadas pelas fontes de óleo. Os tratamentos não influenciaram o peso de abate, o peso de carcaça quente, o pH da carcaça uma hora e 48 horas após o abate, o rendimento de carcaça, a cor, as PPC e a FC. O pH foi maior nas carnes maturadas por 14 dias (P=0,01), em relação àquelas sem maturação. As PPC e a FC foram menores (P=0,01) nas carnes maturadas por 14 dias. O óleo de linhaça apresentou menor estabilidade oxidativa seguidos do óleo de girassol e soja. As fontes de óleo não afetaram a concentração dos lipídios do plasma sanguíneo, no entanto, os níveis de VLDL, LDL, HDL, colesterol e triacilgliceróis foram maiores (P<0,01) no final do experimento em relação ao início. Não houve interação entre a espessura de gordura subcutânea (EGS) avaliada no abate e as dietas e efeito das fontes de óleo sobre os valores de TBARS, lipídios e colesterol. Não foi encontrado o 7-cetocolesterol nas carnes. O pH das carnes expostas por um e três dias sob condições de varejo, não foram influenciadas pela dieta nem pela interação da dieta e dos dias de exposição. No entanto, foi observado o efeito de tempo (P<0,01), as carnes expostas por três dias tiveram valores de pH maiores que as carnes expostas por um dia. A cor L*, a* e b* das carnes expostas em gôndola, sob condições de varejo não foi influenciado pela dieta, pelos dias de exposição e nem pela interação dos dias de exposição e dietas. Os ácidos graxos C18:1 n-9, C20:3 n-6 e C20:5 n-3 apresentaram interação entre a EGS e a dieta (P<0,05). O C18:1 cis 6 apresentou maiores concentrações (P<0,05) nas carnes provenientes dos animais alimentados com óleo de linhaça e soja, em comparação com as carnes provenientes da dieta controle. O C18:3 n-3 apresentou maiores concentrações nas carnes de animais alimentados com linhaça (P<0,05), em comparação com os demais tratamentos. O aroma e a textura da carne avaliados em análise sensorial realizada com consumidores não foram alterados pelos tratamentos. A carne dos animais alimentados com óleo de girassol resultou em maiores notas para o sabor (P<0,01), em relação à carne proveniente de animais alimentados com óleo de soja. As dietas controle e girassol resultaram em carnes mais suculentas e com maior aceitabilidade global (P<0,01), em relação ao tratamento soja. Independentemente do tipo de óleo utilizado na dieta dos animais, não houve influência no desempenho e nas características da carcaça. O óleo de linhaça proporcionou carnes com perfil de ácidos graxos mais favorável para a saúde humana, pois apresentou maiores proporções do ácido linolênico e relações ideais de n6:n3 (4,15). O uso de óleos vegetais na dieta, não prejudicou a aparência das carnes e não proporcionaram oxidação lipídica com a formação de compostos de colesterol oxidados nas carnes expostas sob condições de varejo.
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Backbone networks are responsible for long-haul data transport serving many clients with a large volume of data. Since long-haul data transport service must rely on a robust high capacity network the current technology broadly adopted by the industry is Wavelength Division Multiplexing (WDM). WDM networks enable one single ber to operate with multiple high capacity channels, drastically increasing the ber capacity. In WDM networks each channel is associated with an individual wavelength. Therefore a whole wavelength capacity is assigned to a connection, causing waste of bandwidth in case the connection bandwidth requirement is less than the channel total capacity. In the last half decade, Elastic Optical Networks (EON) have been proposed and developed based on the fexible use of the optical spectrum known as the exigrid. EONs are adaptable to clients requirements and may enhance optical networks performance. For these reasons, research community and data transport providers have been demonstrating increasingly high interest in EONs which are likely to replace WDM as the universally adopted technology in backbone networks in the near future. EONs have two characteristics that may limit its ecient resources use. The spectrum fragmentation, inherent to the dynamic EON operation, decrease the network capacity to assign resources to connection requests increasing network blocking probability. The spectrum fragmentation also intensifides the denial of service to higher rate request inducing service unfairness. Due to the fact EONs were just recently developed and proposed, the aforementioned issues were not yet extensively studied and solutions are still being proposed. Furthermore, EONs do not yet provide specific features as differentiated service mechanisms. Differentiated service strategies are important in backbone networks to guarantee client\'s diverse requirements in case of a network failure or the natural congestion and resources contention that may occur at some periods of time in a network. Impelled by the foregoing facts, this thesis objective is three-fold. By means of developing and proposing a mechanism for routing and resources assignment in EONs, we intend to provide differentiated service while decreasing fragmentation level and increasing service fairness. The mechanism proposed and explained in this thesis was tested in a EON simulation environment and performance results indicated that it promotes beneficial performance enhancements when compared to benchmark algorithms.
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In this paper, we propose an original method to geoposition an audio/video stream with multiple emitters that are at the same time receivers of the mixed signal. The obtained method is suitable when a list of positions within a known area is encoded with precision tailored to the visualization capabilities of the target device. Nevertheless, it is easily adaptable to new precision requirements, as well as parameterized data precision. This method extends a previously proposed protocol, without incurring in any performance penalty.
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The electrochemical behavior of methanesulfonic acid on platinum single crystal electrode surfaces is investigated by cyclic voltammetry and infrared spectroscopy measurements. The results are compared with the voltammetric profiles of perchloric and trifluoromethanesulfonic acids. The differences are interpreted in terms of the effect of the anion on the structure of water. No adsorbed species are detected by infrared spectroscopy.