221 resultados para Molds


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[ES]Las compañías líderes del mundo textil compiten cada día por ser las número 1 en cuanto a ventas se refiere. Para ello, son necesarias diferentes estrategias de venta. Una de ellas es la adición de diferentes adornos de plástico que hacen que el comprador se fije en sus productos. Por otro lado, las tecnologías de mecanizado están en pleno avance y la fabricación de piezas o moldes es cada vez más eficiente. Por eso en este trabajo se quiere analizar y estudiar la fabricación de un molde de inyección de plástico con el logotipo de una de las marcas más famosas en el mundo, Adidas. Se ha de llevar a cabo un estudio de los posibles materiales a utilizar para el molde, así como, las distintas alternativas de mecanizado que hoy en día se emplean para este tipo de procesos. Además, los avances en los distintos programas CAD/CAM son de especial ayuda para este tipo de trabajos. Estos programas son capaces de trazar las trayectorias más eficientes a la hora de mecanizar distintos tipos de piezas y postprocesar la programación de dichas trayectorias para luego ser introducidas en los centros CNC.

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Esta dissertação tem o objetivo geral de analisar o protagonismo que o Instituto Ayrton Senna (organização do Terceiro Setor) tem alcançado na escola pública ao funcionar como braço operativo do empresariado com responsabilidade social na difusão da concepção burguesa de mundo, num contexto histórico do Neoliberalismo da Terceira Via. Esta penetração dos valores empresariais na escola pública se dá através do consenso em torno da falência do Estado na prestação do serviço público que, por sua vez, deveria ser prestado por organizações da sociedade civil (ONGs) em função de sua suposta maior eficiência (pautada nos moldes do mercado). O objetivo específico é identificar como o Instituto Ayrton Senna (IAS), através da concepção de cidadania burguesa pode ressignificar o papel social da escola pública no município do Rio de Janeiro através do desenvolvimento do Programa Acelera Brasil (PAB). A hipótese central é que o IAS, ao aplicar o PAB, ressignifica o papel social da escola pública, atuando como operador do capital ao incorporar a lógica fabril nas escolas públicas, (identificação da qualidade na educação com certificação e treinamento para a realização de avaliações como condição de cidadania) associada a uma face mais humana do capital, introduzindo elementos da noção de capital social, que insere, entre outros, uma relação harmoniosa entre o Estado, a sociedade civil (entendida como Terceiro Setor) e o mercado.

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Abuso sexual infantil é tomado na acepção do construcionismo social, como tipo classificatório, e com uma abordagem histórica. As fortes cargas moral e emocional da categoria são sublinhadas, assim como a noção de carreira moral da criança abusada e de abusador. A psicologia é um dos campos e disciplinas que construiu a categoria e a molda diariamente em suas práticas, teorizações e inclusão em instituições sociais e políticas. A dissertação busca analisar esta moldagem numa amostra de laudos psicológicos relativos a acusações de abuso sexual, constantes de processos de Varas de Família e Varas Criminais no Judiciário do Rio de Janeiro. Os laudos analisados são de autoria de psicólogos do quadro do Tribunal de Justiça do Estado do Rio de Janeiro (TJ-RJ), de psicólogos nomeados ad hoc, de instituições de atendimento a vítimas de violência sexual e de consultórios particulares. Como complementação, são analisadas entrevistas feitas com cinco psicólogos do quadro do TJ-RJ sobre laudos em acusações de abuso sexual infantil e sobre a categoria, afirmando a presença permanente desta, apesar de não mais como um boom (ocorrido no início dos anos 2000), em processos de guarda e visitação de filhos e criminais. A análise constatou a presença de duas posturas da psicologia, a das Varas de Família, que trabalha com a correlação litígio-falsa acusação de abuso sexual- alienação parental, em visão determinista, e a das Varas Criminais, marcada pela exclusão da avaliação do homem acusado e por fortes preconcepções, apoiadas na psicologia do abuso sexual, sobre a amplitude dos abusos sexuais e o testemunho da criança vítima e dos acusadores. Noções controversas de manuais clássicos da psicologia do abuso sexual, da psiquiatria e do senso comum sobre vitimização, sequelas, síndromes, pedofilia estão presentes nos laudos, assim como, mais raramente, o reconhecimento da sexualidade infantil e adolescente. O homem pode aparecer como um pai vitimizado ou um monstro moralmente desqualificado.

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Comprehensive understanding of the long-term performance of cement-bentonite slurry trench cut-off walls is essential as these mixes may degrade when exposed to aggressive environments or when subjected to prolonged drying. A series of wetting-drying and immersion experiments was carried out to evaluate the durability characteristics of laboratory mixed samples and block field samples from 40 days to 11 years of age. For the wetting-drying tests, the samples buried in medium graded sand were subjected to periodical flooding and drying cycles. They were then used for permeability testing and unconfined compressive strength (UCS) testing. For the immersion tests, the samples confined in perforated molds were submerged in magnesium sulfate solution for 16 weeks and their microstructures were then analyzed using X-ray diffraction (XRD) technique. This paper identifies the effects of contaminant exposure on durability of cement-bentonite and the effects of aging by comparing 11 years old samples to younger samples. Test results showed that young or previously contaminated cement-bentonite mixes are more susceptible to sulfate attack than old or less contaminated mixes. Copyright ASCE 2008.

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Results of investigations carried out to improve the process of 'Colombo-curing' of mackerel are presented in this paper. Optimum composition of salt and gorujka puli (malabar tamarind, Garcinia cambogea) to be used in the pickle mixture to give a product of good organoleptic and chemical characteristics have been worked out. Sodium benzoate is used as a preservative against the attack of molds, 'red' etc.

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During a two years research hydrogen peroxide efficacy evaluated for Persian sturgeon, Chinese carps and common carp eggs. These series of the experiments conducted in various conditions different concentration of hydrogen peroxide include 250, 500, 750, 1,000 1,500 2,000 3,000 and 9,000 PPM used as ten and fifteen minutes baths, compared with Malachite green and natural control . In the next phase effect of Levaemisole hydrochloride as an immunostimulator which applied as 5 mg/I in twenty minutes baths from day sixth after hatch evaluated by daily mortality rate and leukocytes counts. The results shown that according fertilization percent and temperature condition hydrogen peroxide at 1,000 and 1,500 PPM concentrations is a effective antifungal agent during incubation periods of Persian sturgeon and even sometimes increasing hatching rates significantly comparing with natural controls and Malachite green. In Chinese carps although hydrogen peroxide controls water molds but it is not recommended in high temperatures because it make shortened incubation time and mold infections will decrease. Also the results shown 750 PPM concentration of hydrogen peroxide in common carp eggs controls water moulds infections and increase hatching rate significantly comparing with Malachite green and natural control. Daily mortality rates accessing of Persian sturgeon fries show that 20 minutes baths of 5mg/1 levamisole hydrochloride decreases daily mortality rate during yolk sac absorption. Nitrogenous compounds: nitrate and ammonium differ significantly between treated tanks with control. Blood leucocytes concentrations as an immune index was different significantly in treated fishes by levamisole hydrochloride comparing with controls. In Chinese carps because yolks sac absorption time is short there is not necessary to use the levamisole hydrochloride. Although treated larvae were more active than controls. As a result our suggestions is to use hydrogen peroxide in Persian sturgeon and common carp artificial propagation and also suggest the use levamisole hydrochloride for Persian sturgeon beside management method in stress and pollution condition

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The introduction of new materials and processes to microfabrication has, in large part, enabled many important advances in microsystems, labon- a-chip devices, and their applications. In particular, capabilities for cost-effective fabrication of polymer microstructures were transformed by the advent of soft lithography and other micromolding techniques 1,2, and this led a revolution in applications of microfabrication to biomedical engineering and biology. Nevertheless, it remains challenging to fabricate microstructures with well-defined nanoscale surface textures, and to fabricate arbitrary 3D shapes at the micro-scale. Robustness of master molds and maintenance of shape integrity is especially important to achieve high fidelity replication of complex structures and preserving their nanoscale surface texture. The combination of hierarchical textures, and heterogeneous shapes, is a profound challenge to existing microfabrication methods that largely rely upon top-down etching using fixed mask templates. On the other hand, the bottom-up synthesis of nanostructures such as nanotubes and nanowires can offer new capabilities to microfabrication, in particular by taking advantage of the collective self-organization of nanostructures, and local control of their growth behavior with respect to microfabricated patterns. Our goal is to introduce vertically aligned carbon nanotubes (CNTs), which we refer to as CNT "forests", as a new microfabrication material. We present details of a suite of related methods recently developed by our group: fabrication of CNT forest microstructures by thermal CVD from lithographically patterned catalyst thin films; self-directed elastocapillary densification of CNT microstructures; and replica molding of polymer microstructures using CNT composite master molds. In particular, our work shows that self-directed capillary densification ("capillary forming"), which is performed by condensation of a solvent onto the substrate with CNT microstructures, significantly increases the packing density of CNTs. This process enables directed transformation of vertical CNT microstructures into straight, inclined, and twisted shapes, which have robust mechanical properties exceeding those of typical microfabrication polymers. This in turn enables formation of nanocomposite CNT master molds by capillary-driven infiltration of polymers. The replica structures exhibit the anisotropic nanoscale texture of the aligned CNTs, and can have walls with sub-micron thickness and aspect ratios exceeding 50:1. Integration of CNT microstructures in fabrication offers further opportunity to exploit the electrical and thermal properties of CNTs, and diverse capabilities for chemical and biochemical functionalization 3. © 2012 Journal of Visualized Experiments.

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捷安肽素是一种由枯草芽孢杆菌(Bacillus subtilis)ZK 产生的抗真菌多肽。本文以柑桔青霉菌(Penicillium italicum)和绿霉菌(Penicillium digitaum)为供试真菌,研究了捷安肽素的抑菌性能及作用机理,为捷安肽素开发为有效的生物杀菌剂提供理论依据。全文共分两部分:第一部分:捷安肽素对柑桔青霉菌和绿霉菌抑制效果研究。采用琼脂扩散法测定捷安肽素对柑桔青霉菌和绿霉菌的抑菌活性。53.9 µg/mL 捷安肽素对绿霉菌和青霉菌的抑菌圈直径分别为26.7mm 和24.1mm。结果表明捷安肽素能够抑制柑桔青绿霉菌的生长,柑桔绿霉菌比青霉菌对捷安肽素敏感。在柑桔果实上,研究了不同浓度、不同接入时间的捷安肽素对柑桔青霉病和绿霉病的防治效果,并与常用化学杀菌剂抑霉唑、咪鲜胺、甲基硫菌灵和多菌灵作比较。53.9 µg/mL捷安肽素处理柑桔果实,柑桔青霉病和绿霉病发病率分别为5.0 %和5.3 %,比对照低95.0 %和94.7 %;柑桔青霉病和绿霉病的病情指数分别为1.87 和2.18,比对照低73.73 和97.82。结果表明,捷安肽素能够有效地防治柑桔青绿霉病。与对照相比,捷安肽素先于或后于柑桔青绿霉菌接入时,对柑桔青绿霉菌均有抑制作用,但抑制效果随接入间隔时间的增长而降低。第二部分:捷安肽素对绿霉菌作用机理研究。首先在光学显微镜和透射电镜下观察捷安肽素处理后绿霉菌菌丝表面形态结构与菌丝体内超微结构的变化。形态观察发现,捷安肽素处理24h以内,绿霉菌菌丝结构无变化。捷安肽素作用36h后,绿霉菌菌丝不规则缢缩和膨大。48h后,在绿霉菌菌丝顶端、中部、末端的多处细胞均可发生畸形的球状结构,这种畸变结构随处理的延长而增加,致使细胞成为捻珠状。处理72 h后,畸变球形细胞开始断裂离解。处理96h后,镜下几乎无完整菌丝,成单个的球状细胞,部分细胞出现破裂。而对照菌丝表面光滑,结构完整。通过透射电镜观察发现,与对照相比,捷安肽素处理后,绿霉菌细胞壁、细胞膜轮廓模糊不清,细胞质外泄。推测捷安肽素能够使绿霉菌细胞膜通透性发生改变。进一步实验利用紫外-可见分光光度计检测捷安肽素作用后绿霉菌胞外液紫外吸光度的变化,表明捷安肽素作用于绿霉菌菌丝后,细胞内蛋白质、核酸缓慢泄漏。通过Atomscan Advantage单道扫描等离子体发射光谱仪(ICP)测定捷安肽素作用后菌丝体内K+浓度的改变,结果表明捷安肽素作用于柑桔绿霉菌1h内,菌丝体内K+含量迅速下降,为对照绿霉菌K+含量的37.53 %,1 h后菌丝体内K+含量变化趋于平缓。K+的迅速泄漏,以及蛋白质、核酸的泄漏表明捷安肽素通过迅速改变绿霉菌细胞膜通透性,使绿霉菌菌丝生长受到抑制。Jiean-peptide produced by Bacillus subtilis ZK has broad-spectrumresistance to plant pathogens. In this study, we investigated the antifungal propertyand the possible antifungal mechanism of jiean-peptide against two commonphytopathogenic fungi of citrus fruits: blue molds (P. italicum) and green molds (P.digitatum).The paper involved two parts:Part 1 is the study of the antifungal property of jiean-peptide against blue moldsand green molds of citrus fruits. The in vitro inhibition effect of jiean-peptide againstblue molds and green molds was detected by agar diffusion method. The diameters ofinhibition zones of green molds and blue molds are 26.7mm and 24.1mm respectivelyby treating with 53.9 µg/mL jiean-peptide. It shows that jiean-peptide effectivelyinhibits the both phytopathogenic fungi, and it is more effective for inhibiting greenmolds than blue molds. The effectiveness of jiean-peptde to inhibit green molds andblue molds in vivo was investigated compared with four conventional fungicides thatare imazalil, prochloraz, carbendazin and methylthiophanate. The result is that the incidences of the blue mold disease and green mold disease are 5.0 % and 5.3 %, thedisease severities are 1.87 and 2.18 respectively when citrus are inoculated with 53.9µg/ml jiean-peptide. The decay incidences and disease severities were significantlyreduced by treating with jiean-peptide compared with the control. The results indicateJiean-peptide is effective for controlling blue molds and green molds on citrus. Theoptimized inoculation time was also investigated. When inoculated with jiean-peptideat 0 h, 6 h, 12 h, 24 h and 48 h before or after pathogens’ inoculation, Jiean-peptidecan suppress the occurrence of blue molds and green molds compared with the control, but the effect of later inoculation decreases compared with the inoculation at the sametime.In Part 2, we investigated the possible antifungal mechanism against greenmolds of citrus. At first, we observed the exterior morphological changes andultrastructural changes of blue molds under light microscopy (LM) and transmissionelectron microscopy (TEM). Compared with untreated control cells which aregenerally uniform in shape, the appearances of treated hyphae change obviously. Itshows that some cells of hyphae irregularly shrink or enlarge when cultured for 36h.When the treating time of jiean-peptide increases, the aberrance of the hyphaebecomes more obvious, and hyphae exhibit the moniliform appearances. Finally, thereis no intact hypha leaved except only single cells, and some of which appear fractured.By transmission electron microscopy (TEM) observation, we find that the outline ofthe cell wall and the cell membrane of hyphae are blurry, and the cytoplasma oozesout. The observation result under LM and TEM suggests that jiean-peptide mightchange the permeability of the cell membrane. So we conducted further experiment todetect the change of permeability when the cells of blue molds were treated withjiean-peptide. And the effect of jiean-peptide on non-growing cells of blue molds wastested. By the spectrophotometer measurement, we found that compounds with lightabsorption at 260 nm and 280 nm were released and amounts increased within 12 hcompared with the control. Moreover, by the ICP measurement, the leakage of K+occurred immediately in the presence of jiean-peptide within 1 h, but with nearly nofurther change after 1 h. All these results indicate that jiean-peptide could change themembrane permeability of blue molds immediately and result in leaking nucleotides,proteins and K+ from cells.

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BACKGROUND: Invasive fungal infections (IFIs) are a major cause of morbidity and mortality among organ transplant recipients. Multicenter prospective surveillance data to determine disease burden and secular trends are lacking. METHODS: The Transplant-Associated Infection Surveillance Network (TRANSNET) is a consortium of 23 US transplant centers, including 15 that contributed to the organ transplant recipient dataset. We prospectively identified IFIs among organ transplant recipients from March, 2001 through March, 2006 at these sites. To explore trends, we calculated the 12-month cumulative incidence among 9 sequential cohorts. RESULTS: During the surveillance period, 1208 IFIs were identified among 1063 organ transplant recipients. The most common IFIs were invasive candidiasis (53%), invasive aspergillosis (19%), cryptococcosis (8%), non-Aspergillus molds (8%), endemic fungi (5%), and zygomycosis (2%). Median time to onset of candidiasis, aspergillosis, and cryptococcosis was 103, 184, and 575 days, respectively. Among a cohort of 16,808 patients who underwent transplantation between March 2001 and September 2005 and were followed through March 2006, a total of 729 IFIs were reported among 633 persons. One-year cumulative incidences of the first IFI were 11.6%, 8.6%, 4.7%, 4.0%, 3.4%, and 1.3% for small bowel, lung, liver, heart, pancreas, and kidney transplant recipients, respectively. One-year incidence was highest for invasive candidiasis (1.95%) and aspergillosis (0.65%). Trend analysis showed a slight increase in cumulative incidence from 2002 to 2005. CONCLUSIONS: We detected a slight increase in IFIs during the surveillance period. These data provide important insights into the timing and incidence of IFIs among organ transplant recipients, which can help to focus effective prevention and treatment strategies.

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Specimens of the polyplacophoran mollusk 'Helminthochiton' thraivensis Reed from the Upper Ordovician of southwest Scotland provide rare examples of complete valve series preserved in near life position, albeit as external molds. Application of high-resolution X-ray microtomography to one such specimen has revealed the exceptional preservation of its last meal, which included elements of a crinoid column, in its intestine. The interaction was either predatory or scavenging; extant chitons are not known to be crinoidivorous. This is the earliest direct record of predation or scavenging on crinoids in the fossil record. It is also the first indication that the broad axial canal of primitive crinoids may have contained nutritious tissues. The predatory or scavenging habit of H. thraivensis is consistent with its inferred phylogenetic position as a stem-group aplacophoran and provides new data suggesting an origin of carnivory early in the evolution of this clade.

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Rotational molding is a process used to manufacture hollow plastic products, and has been heralded as a molding method with great potential. Reduction of cycle times is an important issue for the rotational molding industry, addressing a significant disadvantage of the process. Previous attempts to reduce cycle times have addressed surface enhanced molds, internal pressure, internal cooling, water spray cooling, and higher oven air flow rates within the existing process. This article explores the potential benefits of these cycle time reduction techniques, and combinations of them. Recommendations on a best practice combination are made, based on experimental observations and resulting product quality. Applying the proposed molding conditions (i.e., a combination of surface-enhanced molds, higher oven flow rates, internal mold pressure, and water spray cooling), cycle time reductions of up to 70% were achieved. Such savings are very significant, inviting the rotomolding community to incorporate these techniques efficiently in an industrial setting. POLYM. ENG. SCI., 49:1846-1854, 2009. (C) 2009 Society of Plastics Engineers

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Large, thin (50 mu m) dry polymer sheets containing numerous surface-enhanced Raman spectroscopy (SERS) active Ag nanopartide aggregates have been prepared by drying aqueous mixtures of hydroxyethylcelloulose (HEC) and preaggregated Ag colloid in 10 x 10 cm molds. In these dry films, the particle aggregates are protected from the environment during storage and are easy to handle; for example, they can be cut to size with scissors. When in use, the highly swellable HEC polymer allowed the films to rapidly absorb aqueous analyte solutions while simultaneously releasing the Ag nanoparticle aggregates to interact with the analyte and generate large SERS signals. Either the films could be immersed in the analyte solution or 5 mu L droplets were applied to the surface; in the latter method, the local swelling caused the active area to dome upward, but the swollen film remained physically robust and could be handled as required. Importantly, encapsulation and release did not significantly compromise the SERS performance of the colloid; the signals given by the swollen films were similar to the very high signals obtained from the parent citrate-reduced colloid and were an order of magnitude larger than a commercially available nanoparticle substrate. These "Poly-SERS" films retained 70% of their SERS activity after being stored for 1 year in air. The films were sufficiently homogeneous to give a standard deviation of 3.2% in the absolute signal levels obtained from a test analyte, primarily due to the films' ability to suppress "coffee ring" drying marks, which meant that quantitative analysis without an internal standard was possible. The majority of the work used aqueous thiophenol as the test analyte; however, preliminary studies showed that the Poly-SERS films could also be used with nonaqueous solvents and for a range of other analytes including theophylline, a therapeutic drug, at a concentration as low as 1.0 x 10(-5) mol dm(-3) (1.8 mg/dm(3)), well below the sensitivity required for theophylline monitoring where the target range is 10-20 mg/dm(3).

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As an emerging hole-machining methodology, helical milling process has become increasingly popular in aeromaterials manufacturing research, especially in areas of aircraft structural parts, dies, and molds manufacturing. Helical milling process is highly demanding due to its complex tool geometry and the progressive material failure on the workpiece. This paper outlines the development of a 3D finite element model for helical milling hole of titanium alloy Ti-6Al-4V using commercial FE code ABAQUS/Explicit. The proposed model simulates the helical milling hole process by taking into account the damage initiation and evolution in the workpiece material. A contact model at the interface between end-mill bit and workpiece has been established and the process parameters specified. Furthermore, a simulation procedure is proposed to simulate different cutting processes with the same failure parameters. With this finite element model, a series of FEAs for machined titanium alloy have been carried out and results compared with laboratory experimental data. The effects of machining parameters on helical milling have been elucidated, and the capability and advantage of FE simulation on helical milling process have been well presented.

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This paper written in Spanish gives hints on what to do to control mold after the flooding in October 2015 in South Carolina. Topics include: presence of mold after a flood, signs of mold, people at greatest risk for health effects from mold, possible health effects of mold exposure and cleaning wet or moldy Items after a flood. It also gives web sites for additional information and resources.

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Agricultural workers especially poultry farmers are at increased risk of occupational respiratory diseases. Epidemiological studies showed increased prevalence of respiratory symptoms and adverse changes in pulmonary function parameters in poultry workers. In poultry production volatile organic compounds (VOCs) presence can be due to some compounds produced by molds that are volatile and are released directly into the air. These are known as microbial volatile organic compounds (MVOCs). Because these compounds often have strong and/or unpleasant odors, they can be the source of odors associated with molds. MVOC's are products of the microorganisms primary and secondary metabolism and are composed of low molecular weight alcohols, aldehydes, amines, ketones, terpenes, aromatic and chlorinated hydrocarbons, and sulfur-based compounds, all of which are variations of carbon-based molecules.