A multistage hierarchical algorithm for hand shape recognition

This paper represents a multistage hierarchical algorithm for hand shape recognition using principal component analysis (PCA) as a dimensionality reduction and a feature extraction method. The paper discusses the effect of image blurring to build data manifolds using PCA and the different ways to construct these manifolds. In_order to classify the hand shape of an incoming sign object and to be invariant to linear transformations like translation and rotation, a multistage hierarchical classifier structure is used. Computer generated images for different Irish Sign Language shapes are used in testing. Experimental results are given to show the accuracy and performance of the proposed algorithm

A review on formability prediction and constitutive damage models of sheet forming of magnesium alloys

In recent years, the demand for using magnesium (Mg) alloys has significantly increased in several industrial fields. Due to their favorable strength/weight ratio thus Mg alloy demonstrating a valid replacement for aluminum alloys and High Strength Steels particularly for the production of lightweight parts in aerospace and automotive industries. However the formability of Mg at cold forming conditions is significantly poor and determination of the material formability need special testing procedures and understanding of material failure mechanism. FLD is commonly used to characterize the formability of materials and the key feature of FLD is the forming limit curve (FLC). This paper provides a review on the determination of strain-based and stress-based forming limit diagrams is introduced in this paper. In addition, the constitutive damage models for predicting and characterizing the forming limits of magnesium alloy sheet metals under a wide range of forming conditions at both industrial and scientific level

Nonlinearity reduction of manifolds using Gaussian blur for handshape recognition based on multi-dimensional grids

This paper presents a hand-shape recognition algorithm based on using multi-dimensional grids (MDGs) to divide the feature space of a set of hand images. Principal Component Analysis (PCA) is used as a feature extraction and dimensionality reduction method to generate eigenspaces from example images. Images are blurred by convolving with a Gaussian kernel as a low pass filter. Image blurring is used to reduce the non-linearity in the manifolds within the eigenspaces where MDG structure can be used to divide the spaces linearly. The algorithm is invariant to linear transformations like rotation and translation. Computer generated images for different hand-shapes in Irish Sign Language are used in testing. Experimental results show accuracy and performance of the proposed algorithm in terms of blurring level and MDG size

Photocatalytic degradation of an azo-dye on TiO2/ activated carbon composite material

A sequential adsorption/photocatalytic regeneration process to remove tartrazine, an azo-dye in aqueous solution, has been investigated. The aim of this work was to compare the effectiveness of an adsorbent/photocatalyst composite – TiO2 deposited onto activated carbon (AC) – and a simple mixture of powders of TiO2 and AC in same proportion. The composite was an innovative material as the photocatalyst, TiO2, was deposited on the porous surface of a microporous-AC using metal-organic chemical vapour deposition in fluidized bed. The sequential process was composed of two-batch step cycles: every cycle alternated a step of adsorption and a step of photocatalytic oxidation under ultra-violet (365 nm), at 25◦C and atmospheric pressure. Both steps, adsorption and photocatalytic oxidation, have been investigated during four cycles. For both materials, the cumulated amounts adsorbed during four cycles corresponded to nearly twice themaximumadsorption capacities qmax proving the photocatalytic oxidation to regenerate the adsorbent. Concerning photocatalytic oxidation, the degree of mineralization was higher with the TiO2/AC composite: for each cycle, the value of the total organic carbon removal was 25% higher than that obtained with the mixture powder. These better photocatalytic performances involved better regeneration than higher adsorbed amounts for cycles 2, 3 and 4. Better performances with this promising material – TiO2 deposited onto AC – compared with TiO2 powder could be explained by the vicinity of photocatalytic and AC adsorption sites

Methylmercury varies more than one order of magnitude in commercial European rice

P.M. thanks the Royal Thai Government for funding and C.C.B. thanks the School of Natural and Computing Science and PS Analytical for funding.Peer reviewedPostprin

Antiviral Drugs for Treatment of Human Monkeypox: A Systematic Review/Meta-analysis

Background. On 23 July 2022, the World Health Organization declared a Public Health Emergency of International Concern. Monkeypox is a zoonotic viral disease caused by the monkeypox virus that is transmitted from animals to humans or from human to human. To date, treatment for human monkeypox is mostly symptomatic, as there is no specific standard antiviral treatment. Persons with severe symptoms and signs, immunocompromised patients, children younger than 8 years, and pregnant individuals should be considered for specific antiviral treatment. Objective. This study aims to assess effectiveness of antiviral drugs in treatment of human monkeypox. Methodology. Published clinical trials and cohort studies on the role of antivirals in the management of human monkeypox that were identified through a comprehensive search of electronic databases up to April 1, 2023. The patients included were children and adults confirmed with monkeypox. The diagnosis was based on PCR or clinical symptoms. The intervention was antivirals administration in human monkeypox patients, versus supportive treatment/placebo. Outcome measured include the duration of monkeypox until recovery, need for hospitalization, and ICU admission. Results. We included four completed studies with 195 participants assessing the safety, pharmacokinetics, and efficacy of antiviral treatments for human monkeypox compared to placebo. Three studies investigated Tecovirimat (st-246), and one investigated Brincidofovir. Both drugs were safe, tolerable, and effective with no serious adverse effects. The other 5 studies were not completed and are ongoing. Conclusion. There are currently no approved antivirals for the treatment of monkeypox; some medications could be authorized for outbreak use and are now under investigation, such as Tecovirimat, Cidofovir, and Brincidofovir