215 research outputs found

    Margarine products quality monitoring using reflectance UV-VIS-SWNIR spectroscopy

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    Margarine is a term that can indicate any of a wide range of butter substitutes. Due to the great diversity of the raw material, margarine end-product quality characteristics are expected to be highly diversified. This article proposes the use of reflectance UV-VIS-SWNIR spectroscopy to monitor the margarine end-product quality properties. The main effort in this work was the development of a fast monitoring procedure to assess the quality of the manufactured margarines. 
The study was performed on two margarine products: regular margarine (less than 80% fat) and reduced-fat margarine (less than 60% fat). The nine product samples were collected during the production line normal operating conditions on different days. The samples had the surface cleaned in order to remove any sign of oxidized material. Then, spectra were collected by a reflectance probe normal to the sample surface. The samples temperature was recorded (10.0± 2.0ºC) and the probe-sample distance was kept constant for all the samples. The integration time was set to 40s for the collection of the five UV/VIS spectra per samples; the three VIS/NIR spectra per sample were collected using a 10s integration time.
The data analysis was performed on each product and for each spectral range independently. The spectra were normalized by its maximum intensity and the corrected for using a robust multiplicative scatter correction algorithm. A principal component analysis was performed to the pre-process spectra and the multivariate statistical process control limits were determined with bootstrap for each product/spectral range.
Results show that UV-VIS-SWNIR reflectance spectroscopy provides a quick and fast assessment of these products characteristics and thus it can be used as an indication of the overall product variability

    Economical adjunction of square roots to groups

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    How large must an overgroup of a given group be in order to contain a square root of any element of the initial group? We give an almost exact answer to this question (the obtained estimate is at most twice worse than the best possible) and state several related open questions.Comment: 5 pages. A Russian version of this paper is at http://mech.math.msu.su/department/algebra/staff/klyachko/papers.htm V2: minor correction

    Chromobacterium violaceum ATCC12472: Multi-drug and ethidium bromide resistant

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    _Chromobacterium violaceum_ is an opportunistic human pathogen causing a range of gastric infections and occasionally septicemia. This Gram-negative bacillus is a common inhabitant of soil and water in tropical and subtropical areas of the world. Infection occurs after contamination of damaged skin exposed to soil or environmental water. Alternatively, systemic infection can follow the aspiration or ingestion of contaminated water. The major features of infections by _C. violaceum_ are, in generally, rapid clinical course, multiple visceral abscesses, and high mortality. Genomic data on the type strain ATCC 12472 has provided a comprehensive basis for detailed studies of pathogenicity, virulence and drug resistance genes. In this study, the susceptibility of this organism was tested on a variety of drugs at different concentrations, in solid and liquid media. _C. violaceum_ shown to be resistance to ampicilin, penicillin, rifampicin, erythromycin, vancomycin and also to ethidium bromide. The bacteria was susceptible to gentamicin, tetracycline, chloramphenicol, cotrimoxazole, kanamycin, streptomycin and nalidixic acid, at the tested concentrations

    Influence of wetting-drying cycles on wood behaviour of coastal pedestrian walkways

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    In the context of inspection and maintenance actions for beach walkways in the North of Portugal, some samples of wood used in their construction were collected ? the Pinus sylvestris wood, widely applied in the country. The sustainability of the beach walkways over natural coastal areas is very dependent on their material durability. One of the main problems of the timber used to build those structures is its behavior under wet-drying cycles. For that reason, this work aimed to simulate the effects of weathering on the long-term bending behavior of pinewood. Weathering slab samples with two decades of service life and new, unused slabs were subjected to wetting?drying cycles and tested between each wetting or drying phase. As the bending test characterizes one of the most representative efforts in pedestrian boardwalk slabs, the bending module of rupture was used as an indicator to characterize the resistance of timber. Thus, in this study, the samples' density, dimensional stability, and mechanical strength were determined at the end of each batch of cycle repetitions. The tests were carried out before and after a set of wetting-drying cycles caused by immersion in water and placement into an oven at 80?C to simulate environmental exposure. Thus, it was intended to simulate the use in service through the realization of successive wetting-drying cycles in a laboratory environment and to evaluate its influence on the density, dimensional stability, and mechanical strength of the pine wood tested. The extreme conditions used in the laboratory pretend to accelerate the degradation of samples and simulate, in a relatively short period, what would need years to occur in service. The results showed that the wood that had never been in service is more susceptible to bending resistance variations with cycles than the one already in service. Thus, after a few wet-drying cycles, the wood without any service life tends to approximate, in terms of bending behavior, to the one with two decades of service. This indicates that the method used could satisfy the need to obtain predictions for long-time behavior in a relatively short period.5A1A-9704-9B0B | Ant?nio ?lvaro Labrincha FerreiraN/

    CT Radiomics in Colorectal Cancer: Detection of KRAS Mutation Using Texture Analysis and Machine Learning

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    In this work, by using descriptive techniques, the characteristics of the texture of the CT (computed tomography) image of patients with colorectal cancer were extracted and, subsequently, classified in KRAS+ or KRAS-. This was accomplished by using different classifiers, such as Support Vector Machine (SVM), Grading Boosting Machine (GBM), Neural Networks (NNET), and Random Forest (RF). Texture analysis can provide a quantitative assessment of tumour heterogeneity by analysing both the distribution and relationship between the pixels in the image. The objective of this research is to demonstrate that CT-based Radiomics can predict the presence of mutation in the KRAS gene in colorectal cancer. This is a retrospective study, with 47 patients from the University Hospital, with a confirmatory pathological analysis of KRAS mutation. The highest accuracy and kappa achieved were 83% and 64.7%, respectively, with a sensitivity of 88.9% and a specificity of 75.0%, achieved by the NNET classifier using the texture feature vectors combining wavelet transform and Haralick coefficients. The fact of being able to identify the genetic expression of a tumour without having to perform either a biopsy or a genetic test is a great advantage, because it prevents invasive procedures that involve complications and may present biases in the sample. As well, it leads towards a more personalized and effective treatmentThis work has received financial support from the Xunta de Galicia (Centro singular de investigación de Galicia, accreditation 2020–2023) and the European Union (European Regional Development Fund—ERDF), Project MTM2016-76969-PS

    Superradiance from an ultrathin film of three-level V-type atoms: Interplay between splitting, quantum coherence and local-field effects

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    We carry out a theoretical study of the collective spontaneous emission (superradiance) from an ultrathin film comprised of three-level atoms with VV-configuration of the operating transitions. As the thickness of the system is small compared to the emission wavelength inside the film, the local-field correction to the averaged Maxwell field is relevant. We show that the interplay between the low-frequency quantum coherence within the subspace of the upper doublet states and the local-field correction may drastically affect the branching ratio of the operating transitions. This effect may be used for controlling the emission process by varying the doublet splitting and the amount of low-frequency coherence.Comment: 15 pages, 5 figure

    A comparison between preterm and full-term infants\u2019 preference for faces [Uma compara\ue7\ue3o entre rec\ue9m-nascidos prematuros e a termo na prefer\ueancia por faces]

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    Objective: Visual preference for faces at birth is the product of a multimodal sensory experience experienced by the fetus even during the gestational period. The ability to recognize faces allows an ecologically advantageous interaction with the social environment. However, perinatal events such as premature birth, may adversely affect the adequate development of this capacity. In this study, we evaluated the preference for facial stimuli in preterm infants within the first few hours after birth. Methods: This is a cross-sectional observational study of 59 newborns, 28 preterm and 31 full-term infants. The babies were assessed in the first hours of life, with two white boards in the shape of a head and neck: one with the drawing of a face similar to the human face (natural face), and one with the drawing of misaligned eyes, mouth and nose (distorted face). After the newborn fixated the eyes on the presented stimulus, it was slowly moved along the visual field. The recognition of the stimulus was considered present when the baby had eye or head movements toward the stimulus. Results: The preterm infants, in addition to showing a lower occurrence of orientation movements for both stimuli, on average (1.8 ± 1.1 to natural faces and 2.0 ± 1.2 for distorted ones) also showed no preference for any of them (p = 0.35). Full-term newborns showed a different behavior, in which they showed a preference for natural faces (p = 0.002) and a higher number of orientations for the stimulus, for both natural (3.2 ± 0.8) and distorted faces (2.5 ± 0.9). Conclusion: Preterm newborns recognize facial stimuli and disclose no preference for natural faces, different from full-term newborns. Resumo: Objetivo: A preferência visual por faces ao nascimento é produto de uma experiência sensorial multimodal vivenciada pelo feto ainda no período gestacional. A habilidade de reconhecer faces possibilita uma interação ecologicamente vantajosa com o ambiente social. Entretanto, eventos perinatais, como o nascimento prematuro, podem prejudicar o desenvolvimento adequado dessa habilidade. Nesse trabalho, avaliamos a preferência por estímulos faciais de recém-nascidos prematuros nas primeiras horas após o nascimento. Métodos: Trata-se de um estudo observacional transversal realizado com 59 recém-nascidos, 28 prematuros e 31 nascidos termos. Os bebês foram avaliados, nas primeiras horas de vida, com duas pranchas brancas em formato de cabeça e pescoço: uma com o desenho de uma face similar ao rosto humano (face natural), e outra com o desenho de olhos, boca e nariz desalinhados (face distorcida). Após o recém-nascido fixar o olhar no estímulo apresentado o mesmo era lentamente movimentado ao longo do campo visual. O reconhecimento do estímulo foi considerado presente quando o bebê apresentou movimentos dos olhos ou cabeça em direção ao estímulo. Resultados: Os recém-nascidos prematuros além de apresentarem menor ocorrência de movimentos de orientação para ambos os estímulos, em média (1,8 ± 1,1 para faces naturais e 2,0 ± 1,2 para faces distorcidas), também não apresentaram preferência por qualquer um deles (p = 0,35). Diferente foi o comportamento dos recém-nascidos a termo que apresentaram preferência por faces naturais (p = 0,002) e um número maior de orientações para o estímulo, tanto para faces naturais (3,2 ± 0,8) quanto para faces distorcidas (2,5 ± 0,9). Conclusão: Recém-nascidos prematuros reconhecem os estímulos faciais e não apresentam preferência por faces naturais, diferente de recém-nascidos a termos. Keywords: Model of visual recognition, Visual perception, Newborn, Preterm infant, Full-term infant, Palavras-chave: Reconhecimento visual de modelos, Percepção visual, Recém-nascido, Prematuro, Nascimento a term

    Search based software engineering: Trends, techniques and applications

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    © ACM, 2012. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version is available from the link below.In the past five years there has been a dramatic increase in work on Search-Based Software Engineering (SBSE), an approach to Software Engineering (SE) in which Search-Based Optimization (SBO) algorithms are used to address problems in SE. SBSE has been applied to problems throughout the SE lifecycle, from requirements and project planning to maintenance and reengineering. The approach is attractive because it offers a suite of adaptive automated and semiautomated solutions in situations typified by large complex problem spaces with multiple competing and conflicting objectives. This article provides a review and classification of literature on SBSE. The work identifies research trends and relationships between the techniques applied and the applications to which they have been applied and highlights gaps in the literature and avenues for further research.EPSRC and E

    Assessing the symptoms of Internet Gaming Disorder among college/university students: An international validation study of a self-report

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    The present study evaluated the psychometric properties of a self-report scale for assessing Internet Gaming Disorder (IGD) symptoms according to the DSM-5 and ICD-11 among 3270 college/university students (2095 [64.1%] females; age mean 21.6 [3.1] years) from different countries worldwide. Croatian, English, Polish, Portuguese, Serbian, Turkish, and Vietnamese versions of the scale were tested. The study showed that symptoms of IGD could be measured as a single underlying factor among college/university students. A nine item-symptom scale following DSM-5, and a short four-item scale representing the main ICD-11 symptoms, had sound internal consistency and construct validity. Three symptom-items were found non-invariant across the language samples (i.e., preoccupation with on-line gaming, loss of interests in previous hobbies and entertainment, and the use of gaming to relieve negative moods). This study provides initial evidence for assessing IGD symptoms among college/university students and will hopefully foster further research into gaming addiction in this population worldwide especially with taking into account language/cultural differences
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