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1.
Sensors (Basel) ; 23(21)2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37960591

ABSTRACT

There is only a very short reaction time for people to find the best way out of a building in a fire outbreak. Software applications can be used to assist the rapid evacuation of people from the building; however, this is an arduous task, which requires an understanding of advanced technologies. Since well-known pathway algorithms (such as, Dijkstra, Bellman-Ford, and A*) can lead to serious performance problems, when it comes to multi-objective problems, we decided to make use of deep reinforcement learning techniques. A wide range of strategies including a random initialization of replay buffer and transfer learning were assessed in three projects involving schools of different sizes. The results showed the proposal was viable and that in most cases the performance of transfer learning was superior, enabling the learning agent to be trained in times shorter than 1 min, with 100% accuracy in the routes. In addition, the study raised challenges that had to be faced in the future.


Subject(s)
Learning , Reinforcement, Psychology , Humans , Algorithms , Software , Schools
2.
Front Immunol ; 13: 948419, 2022.
Article in English | MEDLINE | ID: mdl-36148232

ABSTRACT

The autoimmune regulator (AIRE) protein functions as a tetramer, interacting with partner proteins to form the "AIRE complex," which relieves RNA Pol II stalling in the chromatin of medullary thymic epithelial cells (mTECs). AIRE is the primary mTEC transcriptional controller, promoting the expression of a large set of peripheral tissue antigen genes implicated in the negative selection of self-reactive thymocytes. Under normal conditions, the SIRT1 protein temporarily interacts with AIRE and deacetylates K residues of the AIRE SAND domain. Once the AIRE SAND domain is deacetylated, the binding with SIRT1 is undone, allowing the AIRE complex to proceed downstream with the RNA Pol II to the elongation phase of transcription. Considering that the in silico and in vitro binding of the AIRE SAND domain with SIRT1 provides a powerful model system for studying the dominant SAND G228W mutation mechanism, which causes the autoimmune polyglandular syndrome-1, we integrated computational molecular modeling, docking, dynamics between the whole SAND domain with SIRT1, and surface plasmon resonance using a peptide harboring the 211 to 230 residues of the SAND domain, to compare the structure and energetics of binding/release between AIRE G228 (wild-type) and W228 (mutant) SAND domain to SIRT1. We observed that the G228W mutation in the SAND domain negatively influences the AIRE-SIRT1 interaction. The disturbed interaction might cause a disruption in the binding of the AIRE SAND domain with the SIRT1 catalytic site, impairing the AIRE complex to proceed downstream with RNA Pol II.


Subject(s)
RNA Polymerase II , Sirtuin 1 , Chromatin , Gene Expression Regulation , Mutation , Peptides , Sirtuin 1/genetics
3.
Cell Tissue Bank ; 17(4): 689-697, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27718130

ABSTRACT

The aim of this paper was to evaluate through histological analysis of the tissue reaction of deproteinized bovine bone matrix (DBBM) when inserted into the site of intramuscular ectopic sheep. In this study, 16 sheep received 3 groups and these were divided into 2 experimental times: Group 1-sham group, Group 2-particulate autogenous bone and Group 3-DBBM granules. All animals underwent surgical procedures for insertion of materials in an ectopic site (muscles of the lower back and after 3 and 6 months postoperatively, the samples were evaluated by histological analysis. The results indicated that the Sham group showed dense collagen fibers and thin, characterizing fibrosis at 3 and 6 months. In the autograft group there was a significant amount of collagen deposition and decreased inflammation at 6 months postoperatively. Group of DBBM, it was noted the presence of dense connective tissue and surrounding remaining particles was observed the formation of with osteoid characteristic tissue. The DBBM demonstrated biocompatibility, osteoconductivity and small osteogenesis capacity on ectopic site.


Subject(s)
Bone Matrix/chemistry , Bone Matrix/transplantation , Bone Transplantation , Muscles/surgery , Osteogenesis , Animals , Bone Regeneration , Bone Substitutes/chemistry , Bone Substitutes/therapeutic use , Bone Transplantation/methods , Cattle , Collagen/analysis , Muscles/ultrastructure , Proteins/isolation & purification , Sheep
4.
Quintessence Int ; 46(2): 139-44, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25279396

ABSTRACT

The use of dental implants to improve functional and esthetic demands of dentition has increased significantly over the past two decades. Soft and hard tissue management is one of the factors contributing to improved esthetic results. This report describes the correction of an esthetic problem in a single implant combined connective tissue graft and autogenous bone graft. Four months after the surgical procedure, it could be observed that the combination of connective tissue graft and autogenous bone graft resulted in the augmentation of hard and soft tissue in the peri-implant area with favorable esthetic outcomes.


Subject(s)
Alveolar Ridge Augmentation/methods , Bone Transplantation/methods , Connective Tissue/transplantation , Dental Implantation, Endosseous , Dental Implants, Single-Tooth , Esthetics, Dental , Gingiva/surgery , Bicuspid , Female , Humans , Middle Aged , Surgical Flaps
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