Artificial intelligence in biological activity prediction

Artificial intelligence has become an indispensable resource in chemoinformatics. Numerous machine learning algorithms for activity prediction recently emerged, becoming an indispensable approach to mine chemical information from large compound datasets. These approaches enable the automation of compound discovery to find biologically active molecules with important properties. Here, we present a review of some of the main machine learning studies in biological activity prediction of compounds, in particular for sweetness prediction. We discuss some of the most used compound featurization techniques and the major databases of chemical compounds relevant to these tasks.This study was supported by the European Commission through project SHIKIFACTORY100 - Modular cell factories for the production of 100 compounds from the shikimate pathway (Reference 814408), and by the Portuguese FCT under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020.info:eu-repo/semantics/publishedVersio

Antifungal activity of amphotericin B conjugated to nanosized magnetite in the treatment of paracoccidioidomycosis

This study reports on in vitro and in vivo tests that sought to assess the antifungal activity of a newly developed magnetic carrier system comprising amphotericin B loaded onto the surface of pre-coated (with a double-layer of lauric acid) magnetite nanoparticles. The in vitro tests compared two drugs; i.e., this newly developed form and free amphotericin B. We found that this nanocomplex exhibited antifungal activity without cytotoxicity to human urinary cells and with low cytotoxicity to peritoneal macrophages. We also evaluated the efficacy of the nanocomplex in experimental paracoccidioidomycosis. BALB/c mice were intratracheally infected with Paracoccidioides brasiliensis and treated with the compound for 30 or 60 days beginning the day after infection. The newly developed amphotericin B coupled with magnetic nanoparticles was effective against experimental paracoccidioidomycosis, and it did not induce clinical, biochemical or histopathological alterations. The nanocomplex also did not induce genotoxic effects in bone marrow cells. Therefore, it is reasonable to believe that amphotericin B coupled to magnetic nanoparticles and stabilized with bilayer lauric acid is a promising nanotool for the treatment of the experimental paracoccidioidomycosis because it exhibited antifungal activity that was similar to that of free amphotericin B, did not induce adverse effects in therapeutic doses and allowed for a reduction in the number of applications

The development of a video retrieval system using a clinician-led approach

Patient video taken at home can provide valuable insights into the recovery progress during a programme of physical therapy, but is very time consuming for clinician review. Our work focussed on (i) enabling any patient to share information about progress at home, simply by sharing video and (ii) building intelligent systems to support Physical Therapists (PTs) in reviewing this video data and extracting the necessary detail. This paper reports the development of the system, appropriate for future clinical use without reliance on a technical team, and the clinician involvement in that development. We contribute an interactive content-based video retrieval system that significantly reduces the time taken for clinicians to review videos, using human head movement as an example. The system supports query-by-movement (clinicians move their own body to define search queries) and retrieves the essential fine-grained movements needed for clinical interpretation. This is done by comparing sequences of image-based pose estimates (here head rotations) through a distance metric (here Fréchet distance) and presenting a ranked list of similar movements to clinicians for review. In contrast to existing intelligent systems for retrospective review of human movement, the system supports a flexible analysis where clinicians can look for any movement that interests them. Evaluation by a group of PTs with expertise in training movement control showed that 96% of all relevant movements were identified with time savings of as much as 99.1% compared to reviewing target videos in full. The novelty of this contribution includes retrospective progress monitoring that preserves context through video, and content-based video retrieval that supports both fine-grained human actions and query-by-movement. Future research, including large clinician-led studies, will refine the technical aspects and explore the benefits in terms of patient outcomes, PT time, and financial savings over the course of a programme of therapy. It is anticipated that this clinician-led approach will mitigate the reported slow clinical uptake of technology with resulting patient benefit

Effects of perceived cost, service quality, and customer satisfaction on health insurance service continuance

This paper aims to contribute to the universal discourse on financial services continuance behavior by examining the impact of service cost on customers\u27 service-quality perception and service continuance intention. It presents the results of an empirical study that has explored the impacts of service cost, service quality, and customer satisfaction on health insurance customers\u27 behavioral intention toward continuing or discontinuing with their service providers. Very few studies had examined the impact of service cost on service-quality perception. Our study attempts to fill that gap. A sample of 820 customers was surveyed, and 624 usable responses were analyzed with ANOVA, standard multiple regression, and logistic regression. Our findings indicate that, although highly satisfied health insurance customers will most likely retain their current service providers, customer dissatisfaction does not necessarily lead to discontinuance. Our results also provide some operational implications for health insurance managers, with strategies for reducing attrition and improving customer retention

Étude du transfert d'excitation et de cohérence dans la fluorescence sensibilisée mercure-cadmium : I. — Étude théorique

The author studies the coherence and excitation transfer in non-resonant second kind collisions between an optically excited mercury atom and a ground state cadmium atom : Hg(6 3P1) + Cd(5 1S 0) → Hg(6 1S0) + Cd(5 3P 1) + 1.08 eV. A model for the collision in which head-on collisions predominate is presented, and orientation and alignment transfer rates are calculated. In this model, the degree of orientation or alignment of cadmium atoms depends on the direction of the velocity of these atoms after the excitation process. The influence of nuclear spin is studied.L'auteur étudie le transfert d'excitation et de cohérence lors de collisions de seconde espèce non résonnantes entre un atome de mercure excité optiquement et un atome de cadmium dans l'état fondamental : Hg(6 3P 1) + Cd(5 1S0) → Hg(6 1S 0) + Cd(5 3P1) + 1,08 eV. Un modèle de collision dans lequel les collisions frontales jouent un rôle prépondérant est présenté et les taux de transfert d'orientation et d'alignement sont calculés. Dans ce modèle, le degré d'orientation ou d'alignement des atomes de cadmium dépend de la direction de la vitesse de ces atomes après le transfert d'excitation. L'influence du spin nucléaire est étudiée

Étude du transfert d'excitation et de cohérence dans la fluorescence sensibilisée mercure-cadmium : - II. — Résultats expérimentaux

The author studies the mercury-cadmium sensitized fluorescence represented by the relation : Hg(6 3P1) + Cd(5 1S 0) → Hg(6 1S0) + Cd(5 3P 1) + 1.08 eV. The measurement of the excitation transfer cross-section gives σ(0) = 0.34 ± 0.11 Å^2. The Hanle effect is used to study the coherence transfer. The orientation and alignment transfer rates so obtained are α1 = 0.42 ± 0.10 and α2 = 0.47 ± 0.11, respectively. An experiment in which mercury vapour is isotropically excited shows that the senzitized fluorescence line emitted in a given direction may be polarized if one detects only a portion of this line. It is concluded that the excitation transfer is anisotropic. The experimental results are explained by means of a model for the collisions presented by the author in which head-on collisions predominate.L'auteur étudie la fluorescence sensibilisée mercure-cadmium représentée par la relation : Hg(6 3P1) + Cd(5 1S 0) → Hg(6 1S0) + Cd(5 3P 1) + 1,08 eV. La mesure de la section efficace de transfert d'excitation donne : σ(0) = 0,34 ± 0,11 Å^2. Le transfert de cohérence est étudié au moyen de l'effet Hanle. Les taux de transfert d'orientation et d'alignement obtenus sont respectivement : α1 = 0,42 ± 0,10 et α2 = 0,47 ± 0,11. Une expérience dans laquelle la vapeur de mercure est excitée de façon isotrope montre que la raie de fluorescence sensibilisée émise dans une direction donnée peut être polarisée si on détecte une partie seulement de cette raie. On en conclut que le transfert d'excitation est anisotrope. Les résultats sont en accord raisonnable avec les prévisions d'un modèle de collisions présenté par l'auteur et dans lequel les collisions frontales jouent un rôle prépondérant

Relaxation des atomes de mercure métastables 6 3P0

In a mercury-nitrogen mixture illuminated with resonant light pulses at wavelength 253.7 nm, metastable Hg(6 3P0) atoms are produced according to the process : Hg(6 3P1) + N2(X1 Σ g+, v = 0) → Hg(6 3P0) + N 2(X 1Σg+, v = 1). It is observed that the decay of the metastable atoms concentration in the post-excitation depends upon the value of the light flux. This feature is partially explained by (i) a nonequilibrium situation for nitrogen molecules in the v = 1 vibrational level (ii) inelastic collisions Hg(6 3P0) + Hg(6 3P0) → Hg(6 1S0) + Hg*, where Hg* is a highly excited mercury atom. Excitation cross-sections for the 8 1S0, 8 3S 1, 6 1D2, 6 3D1, 6 3D2 and 6 3D3 levels have been measured and are respectively 15, 9,12, 4,10 and 6 Å2.Les atomes métastables Hg(6 3P0) sont créés dans un mélange mercure-azote, éclairé par une impulsion lumineuse à la longueur d'onde de résonance 253,7 nm et suivant le processus : Hg(6 3P1) + N2(X 1Σ g+, v = 0) → Hg(6 3P0) + N2(X 1Σ+g, v = 1). Dans la post-excitation la loi de décroissance de la concentration des atomes métastables dépend de la valeur du flux lumineux à l'excitation. Les phénomènes observés sont partiellement expliqués par (i) la présence de molécules d'azote dans le niveau vibrationnel v = 1 en concentration supérieure à sa valeur à l'équilibre thermique (ii) les collisions inélastiques : Hg(6 3P0) + Hg(6 3P0) → Hg(6 1S0) + Hg*, où Hg* désigne un atome de mercure dans un état très excité. Les sections efficaces d'excitation des niveaux 8 1S0, 8 3S 1, 6 1D2, 6 3D1, 6 3D2 et 6 3D3 ont été mesurées et valent respectivement 15, 9,12, 4,10 et 6 Å2

Effects of applied vibration on triphasic electromyographic patterns in neurologically ballistic head movements.

Vibration of agonist or antagonist muscle tendon produced changes in the triphasic electromyographic pattern of neck muscles; EMG signals were rectified, averaged, and also integrated by planimetry. The triphasic EMG envelopes obtained during fast horizontal head rotation showed unmodified early agonist pulse, the action pulse (PA), under all conditions; increased antagonist pulse, the braking pulse (PB), only with antagonist muscle vibration; and increase of late agonist pulse, the clamping pulse (PC), only with agonist muscle vibration. Vibration experiments can be considered as a model for studying interactions between central and peripheral effects on control of normal movements.Journal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.info:eu-repo/semantics/publishe

Spatial frequency isotropy of an optically pumped

Optically pumped magnetometers are scalar magnetometers which are particularly suitable for mobile applications for which it is necessary to use an isotropic sensor. Our group has recently designed a new helium magnetometer with reduced sensor orientation effects. In this paper, we present the results about frequency spatial isotropy and show frequency effects smaller a 240 pT