Extraction of wood compounds by use of subcritical fluids

A study of the extraction of oak wood compounds with subcritical water-ethanol mixtures as extractant, with an ethanol content between 0-60%, is reported. Identification and characterisation of the extracted compounds have been made by spectrophotometry and gas chromatography with either flame ionisation or mass detectors. Extraction was performed statically manner by use of a single cycle or repeated cycles. All variables affecting the extraction process were studied and optimised. Extraction time and temperature are 60 min and 200ºC, respectively. Comparison of the extract thus obtained with commercial extracts showed the former to be rich in compounds characteristic of the commercial extracts. The method enables manipulation of the extract composition by changing the temperature and water/ethanol ratio used. It is faster than the traditional procedures for obtaining wood extracts

Two-parameter determination in vinegar by a flow injection-pervaporation system

A flow-injection method (FI) for the sequential determination of ethanol and acetic acid in vinegar is reported. The determination of ethanol is based on the oxidation of the pervaporated ethanol by Cr2O7K2. The acetic acid is determined by an acid-base reaction with Thymol Blue as the indicator. Both reactions are monitored photometrically at 600 nm using a single detector. Optimisation studies and assessment of the sequential FI method are also reported. The linear determination range is between 0-12 % (v/v) for ethanol and 0-10 % (grams of acetic acid in 100 ml) for acetic acid. The sample throughput of the sequential manifold is 7 per hour. The new method has been applied to vinegar samples and the results obtained are in excellent agreement with those from the reference methods used in Spain

Semiautomatic flow-injection method for the determination of volatile acidity in wines

A flow-injection (FI) method based on analytical pervaporation was assessed for its routine use in the determination of volatile acidity in winery laboratories. The new method was compared with both the official method and the Mathieu method, which is most often used in Spanish wineries, by testing 30 different wines, including young and aged, and sweet and dry wines from Montilla-Moriles appellation d´origine. The robustness of the new method was established and then all three methods were studied in terms of range of linearity and regression of the calibration curve, repeatability, reproducibility, sensitivity, detection and quantification limits (LOD and LQ, respectively) and time of analysis. The FI method surpasses the Mathieu method in reproducibility and both the Mathieu and official methods in LOD and LQ and sensitivity; it also requires less personnel involvement and shorter analysis time. The statistical criteria established by the “Office International de la Vigne et du Vin” were applied to the data and the results obtained indicated that the differences between the analytical parameters of the 3 methods are not significant and can be applied indistinctly. The correlation of the methods was studied by taking them 2 by 2, and the corresponding equations, coefficients and deviations confirmed the statistical results. Thus, the new method can be used in winery laboratories with clear advantages over its 2 counterparts (the routine and official methods)

Sequential Spectrophotometric determination of methanol and iron in vinegar by a flow injection-pervaporation method

An easily automatable sequential flow-injection-pervaporation method is proposed for the photometric determination of methanol and iron in vinegar. The method is based on separation of the methanol from the sample matrix by pervaporation followed by its oxidation to formaldehyde with permanganate, decolouration of the latter with S2O5-2 and subsequent reaction of formaldehyde with p-rosaniline to yield a violet reaction product with maximum absorption at 567 nm. Iron is determined by an existing method based on reaction with thiocyanate in acidic medium and monitoring at 508 nm. After optimisation by either the univariate or multivariate approaches, as required, the linear range was established for methanol (4-1000 mg L-1) and iron (0.18-20 mg L-1); The proposed method was then compared with reference methods for methanol and iron in terms of repeatability (2.452 mg L-1 and 0.245 mg L-1, respectively), reproducibility (4.435 mg L-1 and 0.356 mg L-1, respectively), detection limit (LOD=82 and 0.234 mg L-1, respectively) and traceability. The throughput was nine samples per hour

Method for the simultaneous determination of total polyphenol and anthocyan indexes in red wines using a flow injection approach

A simultaneous and fast method for the determination of total polyphenol index (t.p.i.) and total anthocyan index (t.a.i.) has been developed by a flow injection approach and a diode array spectrophotometer for monitoring at 280 nm and 520 nm, respectively. Linear ranges were obtained from 20 to 70 index units and from 20 to 500 mg l-1 for t.p.i. and t.a.i., respectively. The results provided by the proposed method agree with those obtained using the polyphenol index at 280 nm and the Ribereau-Gayon method for the determination of total anthocyans. The sample throughput was 25-30 samples per hour. Analytical features such as repeatability, reproducibility and detection and quantification limits as well as the results of a robustness study based on the Steiner-Younden procedure are also given

Determination of ethanol in beverages by flow injection, pervaporation and density measurements

A fast, clean and easy to automate flow injection-pervaporation method for the determination of ethanol in different beverages using density measurements is proposed. The method is based on separation of the ethanol from the sample using a pervaporation module, thus obtaining in the acceptor chamber of the pervaporator a water-alcohol mixture, the density of which is measured. After optimisation by either the univariate or multivariate approach as required, a linear range between 0-40% was established. Then, the assessment of the method versus a reference one was studied in terms of repeatability (0.12% v/v), reproducibility (0.32% v/v), detection limit (0.11% v/v) and traceability. The sample throughput was 15 samples h-1. The method was in agreement with the reference methods used in the European Union

Superheated liquids for the extraction of solid residues from winemaking processes

Solid residues from winemaking process have been subjected to extraction with superheated water-ethanol mixtures. Identification and characterisation of the extracted compounds have been made by spectrophotometry, gas chromatography with either flame ionisation or mass detectors and high performance liquid chromatography with UV detection. The extraction has been performed in a static manner by single or repetitive cycles. All variables affecting the extraction process have been studied and optimised. The extraction time and temperature are 65 min and 210ºC, respectively. Two phases constitute the extract: an aqueous phase, which is rich in phenol compounds and an oily phase, mainly formed by fatty acids. The method allows manipulation of the extract composition by changing the applied pressure, temperature, water-ethanol ratio and pH. The method is faster than the traditional extraction procedures for obtaining valuable compounds from these residues

Automatic learning of gait signatures for people identification

This work targets people identification in video based on the way they walk (i.e. gait). While classical methods typically derive gait signatures from sequences of binary silhouettes, in this work we explore the use of convolutional neural networks (CNN) for learning high-level descriptors from low-level motion features (i.e. optical flow components). We carry out a thorough experimental evaluation of the proposed CNN architecture on the challenging TUM-GAID dataset. The experimental results indicate that using spatio-temporal cuboids of optical flow as input data for CNN allows to obtain state-of-the-art results on the gait task with an image resolution eight times lower than the previously reported results (i.e. 80x60 pixels).Comment: Proof of concept paper. Technical report on the use of ConvNets (CNN) for gait recognition. Data and code: http://www.uco.es/~in1majim/research/cnngaitof.htm

O slackline nas aulas de educação física escolar

INTRODUÇÃO: O estudo pretende expandir os conhecimentos dos assuntos relacionados ao Slackline nas escolas e analisar as possibilidades pedagógicas que esta modalidade pode alcançar, para que futuramente os profissionais possam usufruir de novas modalidades assim como o Slackline para aumentar o leque de capacidades físicas e aprendizados alcançados através do esporte. Existe grande necessidade de mais estudos sobre o tema devido pelo fato do Slackline ser um esporte muito novo e por isso são poucas as pesquisas relacionadas ao conhecimento do assunto. OBJETIVO: O objetivo desse estudo foi mostrar o potencial do Slackline como conteúdo de Educação Física escolar e demonstrar a importância do equilíbrio para as habilidades motoras e postura corporal nos alunos. MATERIAIS E MÉTODOS: Nos matérias e métodos foi feita uma revisão bibliográfica de literatura sobre os temas que tem conexão com o assunto fazendo um estudo aprofundado sobre as características do Slackline. CONSIDERAÇÕES FINAIS: Conclui-se que o Slackline possui diversas características e atributos que podem contribuir bastante na formação dos alunos através dessa vivência do esporte como superação, contribuindo totalmente com o conteúdo das aulas de Educação Física, além de ser uma novidade que explora espaços externos com contato ao ar livre e que proporciona uma maior consciência ambiental. Estreita os laços entre os praticantes criando um espírito de uma família, oferece benefícios físicos e psicológicos, tais como superação, autoconhecimento, melhora da autoestima, desenvolvimento dos reflexos e do equilíbrio, melhora da postura e massa corporal, e aprimoramento de respostas motoras, tudo isso de uma forma lúdica estabelecendo um ambiente mais agradável e de certa forma viciante para a prática da modalidade. Entretanto deve ser destacado que são necessários mais estudos sobre o assunto que é muito recente e pouco falado na área da Educação Física.INTRODUCTION: The study aims to expand the knowledge of issues related to Slackline in schools and analyze the pedagogical possibilities that this mode can reach so that future professionals can take advantage of new modalities as well as the Slackline to increase the range of physical abilities and achieved learnings through sport. There is great need for more studies on the subject due to the fact the Slackline be a very new sport and therefore there is little research related to knowledge of the subject. OBJECTIVE: The aim of this study was to show potential Slackline as school physical education content and demonstrate the importance of balance for motor skills and body posture in students. MATERIALS AND METHODS: In the materials and methods was made a literature literature review on the issues that have connection with the subject making a detailed study of the Slackline characteristics. CONCLUSION: We conclude that the Slackline has different characteristics and attributes that can contribute a lot in the training of students through this experience of sports as overcoming, fully contributing to the content of the physical education classes as well as being a novelty that explores external spaces with outdoor contact and provides greater environmental awareness. Close ties between the practitioners creating a spirit of a family, offers physical and psychological benefits, such as resilience, self-awareness, improved self-esteem, developing reflexes and balance, improved posture and body mass, and improvement of motor responses, all this in a playful way by establishing a more pleasant environment and somewhat addictive way to the sport. However it should be noted that more studies are needed on the subject that is very recent and little spoken in the area of Physical Education