404 research outputs found
Synthesis of poly(1,1'-ferrocenylenevinylene) via McMurry coupling
Com base nas grandes modificações das propriedades de materiais poliméricos resultantes da inclusão de unidades organometálicas, descrevem-se neste trabalho a síntese e a caracterização de um polímero organometálico conjugado com estrutura semelhante à de poli(p-fenilenovinileno) (PPV), o qual apresenta grupos 1,1'-ferrocenileno no lugar de 1,4fenileno em sua cadeia principal. Sintetizado por meio de reação de acoplamento de McMurry de 1,1'-ferrocenodialdeído, o poli(1,1'-ferrocenilenovinileno) (PFV) se apresentou na forma de um sólido de cor laranja, amorfo e insolúvel tanto em solventes polares quanto em apolares. Para caracterização do PFV, empregaram-se os métodos de espectroscopia no infravermelho (FTIR), espectroscopia Raman e análise termogravimétrica (TGA).Motivated by the influence on the physical and chemical properties of polymeric materials caused by the inclusion of organometallic units, the present work is focused on the synthesis and characterization of an organometallic conjugated polymer with similar structure to poly(p-phenylenevinylene) (PPV), in which the phenylene groups are replaced by ferrocenylene units in the main chain. The polymer, poly(1,1'-ferrocenylenevinylene), (PFV), was prepared via McMurry coupling reaction of 1,1'-ferrocenedialdehyde as an orange and amorphous solid, insoluble both in polar and apolar solvents. The characterization of the polymer was carried out employing the following methods: infrared (FTIR) and Raman spectroscopies and thermogravimetric analysis (TGA).FAPESPCNP
The role of radiology in forensic dentistry
Vários métodos são empregados na identificação de restos humanos, sendo que a maioria é baseada na comparação entre dados ante-mortem e post-mortem disponíveis. Embora a técnica da impressão digital seja considerada a mais precisa, em muitos casos ela não pode ser utilizada, especialmente quando os corpos foram mutilados, decompostos, queimados ou fragmentados. Nestas situações, os métodos empregados pela Odontologia Legal tornam-se extremamente valiosos, uma vez que os dentes e as restaurações são muito resistentes à destruição pelo fogo, preservando numerosas características individuais. Assim, oferecem a possibilidade de uma identificação acurada e aceita pelas autoridades legais. Este breve artigo de revisão descreve os principais avanços alcançados pela Odontologia Legal, nos últimos 25 anos, quanto ao emprego de radiografias ante- e post-mortem no processo de identificação. Dentre os diversos assuntos tratados, destacam-se: suportes especialmente confeccionados para facilitar o posicionamento e a fixação de filmes radiológicos intra-orais em falecidos com rigor mortis; dispositivos para facilitar a reprodução da geometria de imagens com as de ante-mortem; métodos envolvendo radiografias digitalizadas, as quais podem ser facilmente manipuladas por métodos computacionais, armazenadas e transmitidas por "modem" aos locais de desastre em massa; procedimentos para determinação de idade, identificação de indivíduos desdentados por meio da comparação de radiografias oclusais do maxilar e estudos de validação de radiografias tiradas com intervalos ante- e post-mortem de até 30 anos.There are various methods for the identification of human remains; most of them are based on comparisons between available ante- and post-mortem data. Although fingerprinting is the most accurate and precise method, in many cases, such as in mutilated, decomposed, burned or fragmented bodies, it cannot be used, and the dental methods become of the utmost importance, since teeth and dental restorations are very resistant to destruction by fire - they keep numerous characteristics, which are quite unique, and offer the possibility of accurate and legally acceptable identification of remains. This brief review describes the progress of forensic dentistry during the last 25 years, regarding the procedures and techniques that use ante-mortem and post-mortem radiographs. Among the discussed progresses one can point out: a specially designed self-supporting film holder that retains intra-oral films in the mouths of deceased persons whose mandibular musculature has been fixed in rigor mortis; positioning devices suitable for reproducing the geometry of ante-mortem radiographic images; methods involving digital radiographs, which can be easily stored in a central archive, retrieved and transmitted, via modem, to mass casualty sites; age estimation procedures; identification of edentulous individuals comparing radiographs of the maxilla; and studies of validation of dental radiographs taken with ante-mortem and post-mortem intervals of up to 30 years
PENAMBAHAN HIDROLISAT PROTEIN IKAN LEMURU (Sardinella lemuru) PADA PEMBUATAN BISKUIT
Protein ikan dapat diekstrak sehingga memperoleh sediaan protein kering. Salah satu sediaan protein kering adalah hidrolisat protein ikan. Hidrolisat protein ikan dapat digunakan dalam memperbaiki karakteristik produk biskuit seperti meningkatkan nilai gizi dan rasa. Tujuan Penelitian ini adalah mengetahui tahapan pembuatan biskuit dengan penambahan hidrolisat protein ikan dan mengetahui mutu dari produk biskuit hidrolisat protein ikan melalui uji proksimat dan uji organoleptik. Tahapan penelitian meliputi pengolahan biskuit dengan penambahan hidrolisat protein ikan 0% (kontrol), 5%, 10%, dan 15%, uji organoleptik dan analisis proksimat. Data yang diperoleh ditampilkan dalam bentuk Gambar, Histogram, dan Tabel kemudian dibahas secara deskriptif. Berdasarkan uji organoleptik biskuit dengan penambahan HPI 10% lebih disukai dibandingkan dengan perlakuan 0% (kontrol), 5% dan 15%. Analisis proksimat biskuit hidrolisat protein ikan menunjukkan bahwa semakin banyak penambahan HPI akan meningkatkan kadar protein biskuit. Kadar protein tertinggi diperoleh pada penambahan HPI 15%
Conductive polymer gas sensor for quantitative detection of methanol in Brazilian sugar-cane spirit
A low-cost chemiresistive gas sensor is described, made by the deposition of a thin film of a conductive polymer, poly(2-dodecanoylsulfanyl-p-phenylenevinylene), doped with dodecylbenzenesulfonic acid (10%, w/w), onto interdigitated electrodes. the sensor exhibits linear electrical conductance changes in function of the concentration of methanol present in sugar-cane spirit in the range between 0.05% and 4.0%. Since the sensor is cheap, easy to fabricate, durable, presents low power consumption, and is not sensitive to ethanol, acetic acid or water, it can be used in portable equipments for monitoring methanol levels in distilled alcoholic beverages such as Brazilian sugar-cane spirit (cachaca). (C) 2011 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Diadema, SP, BrazilUniv São Paulo, Inst Quim, BR-05513970 São Paulo, BrazilUniversidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Diadema, SP, BrazilFAPESP: 06/59464-2CNPq: 303717/2010-6CNPq: 472297/2007-4Web of Scienc
Antifungal Potential Of The Sponge Styllisa Flabelliformis Against The Pathogenic And Resistant Aspergillus Fungi
Together with bacterial and viral infection, fungal infection represents the world's top ten killer diseases, desperately requiring new antifungal drugs. This research aimed to evaluate the antifungal activity of the sponge Styllisa flabelliformis against the pathogenic fungi Aspergillus flavus and Aspergillus parasiticus by the standard agar diffusion technique. Three concentrations (1, 10, and 10 mg/mL) for the extract and 0.5 mg/mL for ketoconazole and fluconazole were prepared and evaluated in triplicate against the tested fungi. Whereas ketoconazole poorly inhibited A. parasiticus and fluconazole weakly inhibited A. flavus, the extract of S. flabelliformis exerted antifungal activity against A. parasiticus (6.8 ± 1.8; 8.3 ± 3.2; and 9.5 ± 2.1) mm and A. flavus (6.8 ± 1.1; 11.5 ± 1.4; and 14.3 ± 1.1) mm 1, 10 and 100 mg/mL respectively. PASS analysis showed jasplakinolide as a promising antifungal agent with potential activity (Pa) of 0.736. STITCH analysis further confirmed that jasplakinolide worked by inhibiting the expression of cytoskeleton genes that prevented fungi from synthesizing chitin and inhibiting the formation of the fungi’s cell walls and hyphae, different from the ergosterol synthesis inhibition in ketoconazole and fluconazole, implying the potential of jasplakinolide as an antifungal agent
3D segmentation of plant root systems using spatial pyramid pooling and locally adaptive field-of-view inference
BackgroundThe non-invasive 3D-imaging and successive 3D-segmentation of plant root systems has gained interest within fundamental plant research and selectively breeding resilient crops. Currently the state of the art consists of computed tomography (CT) scans and reconstruction followed by an adequate 3D-segmentation process.ChallengeGenerating an exact 3D-segmentation of the roots becomes challenging due to inhomogeneous soil composition, as well as high scale variance in the root structures themselves.Approach(1) We address the challenge by combining deep convolutional neural networks (DCNNs) with a weakly supervised learning paradigm. Furthermore, (2) we apply a spatial pyramid pooling (SPP) layer to cope with the scale variance of roots. (3) We generate a fine-tuned training data set with a specialized sub-labeling technique. (4) Finally, to yield fast and high-quality segmentations, we propose a specialized iterative inference algorithm, which locally adapts the field of view (FoV) for the network.ExperimentsWe compare our segmentation results against an analytical reference algorithm for root segmentation (RootForce) on a set of roots from Cassava plants and show qualitatively that an increased amount of root voxels and root branches can be segmented.ResultsOur findings show that with the proposed DCNN approach combined with the dynamic inference, much more, and especially fine, root structures can be detected than with a classical analytical reference method.ConclusionWe show that the application of the proposed DCNN approach leads to better and more robust root segmentation, especially for very small and thin roots
Prediction of autoignition-stabilized flame dynamics in a backward-facing step reheat combustor configuration
Hydrogen combustion in a sequential combustor with a propagation-stabilized flame in the first stage and an autoignition-stabilized flame in the second reheat stage offers fuel flexible and efficient power generation with minimal greenhouse gas emissions. However, unsteady thermoacoustic phenomena driven by the interactions between the flame dynamics and the combustor acoustics can result in large amplitude heat release rate and pressure oscillations, which can cause hardware damage and performance losses. A key component required to understand and predict thermoacoustic oscillations in reheat combustors is the knowledge of the response of the autoignition-stabilized flame to unsteady acoustic and convective disturbances. In this paper, we extend a simplified particle based framework, originally proposed for computing the flame response in a simple one-dimensional reheat combustor configuration (Gopalakrishnan et al. 2021), to a two-dimensional backward-facing step geometry. The present particle based framework treats the flow as a collection of independent Lagrangian fluid elements which evolve in time. The temperature evolution of each fluid particle is computed by integrating the momentum, energy and species mass balance equations for that particle in time. The unsteady heat release rate and instantaneous flame position are then computed by stitching together the particle evolution data. The predictions of the flame response framework are thereafter compared with fully compressible Large eddy simulations (LES) of a reheat flame forced by acoustic and entropy disturbances. The flame response predictions obtained from the present approach match well with the LES data, suggesting that the present particle based framework can be used to compute flame transfer functions of reheat flames and consequently give insight into the thermoacoustic stability characteristics of reheat combustors
ROOT for the HL-LHC: data format
This document discusses the state, roadmap, and risks of the foundational
components of ROOT with respect to the experiments at the HL-LHC (Run 4 and
beyond). As foundational components, the document considers in particular the
ROOT input/output (I/O) subsystem. The current HEP I/O is based on the TFile
container file format and the TTree binary event data format. The work going
into the new RNTuple event data format aims at superseding TTree, to make
RNTuple the production ROOT event data I/O that meets the requirements of Run 4
and beyond
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