Search results for " processing"

Local Directional Multi Radius Binary Pattern

2018

Face recognition becomes an important task performed routinely in our daily lives. This application is encouraged by the wide availability of powerful and low-cost desktop and embedded computing systems, while the need comes from the integration in too much real world systems including biometric authentication, surveillance, human-computer interaction, and multimedia management. This article proposes a new variant of LBP descriptor referred as Local Directional Multi Radius Binary Pattern (LDMRBP) as a robust and effective face descriptor. The proposed LDMRBP operator is built using new neighborhood topology and new pattern encoding scheme. The adopted face recognition system consists of th…

BED: A new dataset for EEG-based biometrics

2021

Various recent research works have focused on the use of electroencephalography (EEG) signals in the field of biometrics. However, advances in this area have somehow been limited by the absence of a common testbed that would make it possible to easily compare the performance of different proposals. In this work, we present a data set that has been specifically designed to allow researchers to attempt new biometric approaches that use EEG signals captured by using relatively inexpensive consumer-grade devices. The proposed data set has been made publicly accessible and can be downloaded from https://doi.org/10.5281/zenodo.4309471 . It contains EEG recordings and responses from 21 individuals…

A new method for morphometric analysis of opal phytoliths from plants.

2014

Micro-morphometry has substantially gained ground in the field of phytolith analysis, but the comparability of results is limited due to the use of different methods. This paper presents a new, user-friendly method based on open-source software (FIJI) that is proposed as a step towards the introduction of a standard method. After obtaining a mask of a phytolith by making a digital drawing, 27 commonly used variables of size and shape are measured automatically. This method is not only useful for phytolith analysis, but may also be used for other fields of morphometric research. Users can furthermore customize the software tool when additional variables are required.

Temperature-induced microstructural changes in shells of laboratory-grown Arctica islandica (Bivalvia).

2021

Bivalve shells are increasingly used as archives for high-resolution paleoclimate analyses. However, there is still an urgent need for quantitative temperature proxies that work without knowledge of the water chemistry–as is required for δ18O-based paleothermometry–and can better withstand diagenetic overprint. Recently, microstructural properties have been identified as a potential candidate fulfilling these requirements. So far, only few different microstructure categories (nacreous, prismatic and crossed-lamellar) of some short-lived species have been studied in detail, and in all such studies, the size and/or shape of individual biomineral units was found to increase with water temperat…

Phosphorylation of serine residues is fundamental for the calcium-binding ability of Orchestin, a soluble matrix protein from crustacean calcium stor…

2003

International audience; Orchestia cavimana is a terrestrial crustacean, which cyclically stores calcium in diverticula of the midgut, in the form of calcified amorphous concretions. These concretions are associated with a proteinaceous matrix, the main constituent of the soluble matrix is Orchestin, an acidic calcium-binding protein [Testenière et al., Biochem. J. 361 (2002) 327-335]. In the present paper, we clearly demonstrate that Orchestin is phosphorylated on serine and tyrosine residues, but that calcium binding only occurs via the phosphoserine residues. To our knowledge, this is the first example of an invertebrate mineralization for which a post-translational modification is clearl…

Hybrid Quantum Mechanics/Molecular Mechanics Simulations with Two-Dimensional Interpolated Corrections:  Application to Enzymatic Processes

2006

Hybrid quantum mechanics/molecular mechanics (QM/MM) techniques are widely used to study chemical reactions in large systems. Because of the computational cost associated with the high dimensionality of these systems, the quantum description is usually restricted to low-level methods, such as semiempirical Hamiltonians. In some cases, the description obtained at this computational level is quite poor and corrections must be considered. We here propose a simple but efficient way to include higher-level corrections to be used in potential energy surface explorations and in the calculation of potentials of mean force. We evaluate a correction energy term as the difference between a high-level …

Phosphorylation of cytochromes P450: First discovery of a posttranslational modification of a drug-metabolizing enzyme

2005

Cytochromes P450 (CYP) are important components of xenobiotic-metabolizing monooxygenases (CYP-dependent monooxygenases). Their regulation by induction, most commonly by transcriptional activation, mediated by xenobiotics, normally substrates of the corresponding CYP, is well known and has been widely studied. Our team has discovered an additional important regulation of xenobiotic-metabolizing CYPs pertaining to posttranslational modification by phosphorylation. Individual CYPs are phosphorylated by different protein kinases, leading to CYP isoenzyme-selective changes in the metabolism of individual substrates and consequent drastic changes in the control of genotoxic metabolites. Best stu…

PREPARATION AND CHARACTERIZATION OF BIOPOLYMERIC POROUS STRUCTURES FOR ADVANCED APPLICATIONS

Porous biopolymers received an increasing academic and industrial interest finding application in several fields such as tissue engineering, bioprocess intensification and waste removal. Tissue engineering combines the knowledge of materials science and bioengineering in order to develop structures able to substitute and restore the normal function of injured or diseased tissues. In this context, polymeric 3D or 2D scaffolds are widely investigated as temporary cell guidance during the tissue restore. Porous biomaterials can offer a versatile and cost effective way for immobilization of filamentous microorganisms in submerged fermentation processes for the production of biologically active …

Cleavage of endometrial α-integrins into their functional forms is mediated by proprotein convertase 5/6.

2012

Background Proprotein convertases (PCs) post-translationally activate a large number of protein precursors through limited cleavage. PC5/6 (PC6) in the human endometrium is tightly regulated during receptivity for embryo implantation. Integrins are transmembrane glycoproteins, some of which play an important role in the adhesive interactions between the trophoblast (blastocyst) and uterine epithelium at implantation. Integrins require PC cleavage for post-translational modification. We hypothesize that pro-integrin-αs in the endometrial epithelium are post-translationally cleaved by PC6 into functional subunits for the binding of blastocyst and adhesion of extracellular matrix proteins. Met…

Neurocognitive endophenotypes in schizophrenia and bipolar disorder: A systematic review of longitudinal family studies

2018

Although there is substantial evidence supporting the existence of neurocognitive impairment in patients diagnosed with schizophrenia (SZ) and bipolar disorder (BD), few studies have explored the field from an endophenotypic perspective. The present systematic review sought to identify longitudinal family studies exploring suitable neurocognitive endophenotypes in unaffected relatives of patients with SZ and/or BD. Following the PRISMA statement, only five follow-up studies met the inclusion criteria, comprising 79 SZ patients, 159 SZ unaffected relatives of SZ, 131 BD patients, 77 unaffected relatives of BD, and 248 controls. Verbal memory, auditory attention, face memory and emotion proce…