Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Neural Netw ; 165: 596-610, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37364470

RESUMO

Although graph representation learning has been studied extensively in static graph settings, dynamic graphs are less investigated in this context. This paper proposes a novel integrated variational framework called DYnamic mixture Variational Graph Recurrent Neural Networks (DyVGRNN), which consists of extra latent random variables in structural and temporal modelling. Our proposed framework comprises an integration of Variational Graph Auto-Encoder (VGAE) and Graph Recurrent Neural Network (GRNN) by exploiting a novel attention mechanism. The Gaussian Mixture Model (GMM) and the VGAE framework are combined in DyVGRNN to model the multimodal nature of data, which enhances performance. To consider the significance of time steps, our proposed method incorporates an attention-based module. The experimental results demonstrate that our method greatly outperforms state-of-the-art dynamic graph representation learning methods in terms of link prediction and clustering.2.


Assuntos
Aprendizagem , Redes Neurais de Computação , Análise por Conglomerados , Distribuição Normal
2.
Appl Netw Sci ; 8(1): 27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250202

RESUMO

Link prediction (LP) has many applications in various fields. Much research has been carried out on the LP field, and one of the most critical problems in LP models is handling one-to-many and many-to-many relationships. To the best of our knowledge, there is no research on discriminative fine-tuning (DFT). DFT means having different learning rates for every parts of the model. We introduce the BuB model, which has two parts: relationship Builder and Relationship Booster. Relationship Builder is responsible for building the relationship, and Relationship Booster is responsible for strengthening the relationship. By writing the ranking function in polar coordinates and using the nth root, our proposed method provides solutions for handling one-to-many and many-to-many relationships and increases the optimal solutions space. We try to increase the importance of the Builder part by controlling the learning rate using the DFT concept. The experimental results show that the proposed method outperforms state-of-the-art methods on benchmark datasets.

3.
IEEE Trans Neural Netw Learn Syst ; 34(2): 1089-1096, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34437071

RESUMO

Non-Euclidean property of graph structures has faced interesting challenges when deep learning methods are applied. Graph convolutional networks (GCNs) can be regarded as one of the successful approaches to classification tasks on graph data, although the structure of this approach limits its performance. In this work, a novel representation learning approach is introduced based on spectral convolutions on graph-structured data in a semisupervised learning setting. Our proposed method, COnvOlving cLiques (COOL), is constructed as a neighborhood aggregation approach for learning node representations using established GCN architectures. This approach relies on aggregating local information by finding maximal cliques. Unlike the existing graph neural networks which follow a traditional neighborhood averaging scheme, COOL allows for aggregation of densely connected neighboring nodes of potentially differing locality. This leads to substantial improvements on multiple transductive node classification tasks.

4.
Front Dent ; 18: 15, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35965696

RESUMO

For many years oral esthetic problems treated by dentists were limited to those involving the teeth without giving consideration to the gingiva. However, today it is well established that these structures should be in balance to appear esthetically pleasing. More than 3mm gingival show during smiling is considered as 'excessive gingival display' also known as "gummy smile", which is not attractive. The current case series, presents three patients with gummy smile managed by lip repositioning surgery, each with 1 year follow up. Our objective was to introduce lip repositioning as a successful treatment modality to decrease gingival show using a simple and conservative surgical approach.

5.
Front Dent ; 17(5): 1-8, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33615303

RESUMO

OBJECTIVES: This study aimed to evaluate the mucograft collagen matrix (CM) to increase keratinized tissue around teeth compared to free gingival graft (FGG). MATERIALS AND METHODS: The present double-blind, randomized, controlled clinical trial studied 12 patients who had 2 mm or less keratinized gingiva bilaterally around mandibular premolars. The 6-month width of keratinized tissue, periodontal parameters (preoperatively and 1, 3, and 6 months postoperatively), color match, pain, and total surgical time were measured. RESULTS: The mean dimensional change of keratinized gingiva 6 months postoperatively was 4.1±0.7 mm for FGG and 8±1.7 mm for CM. Periodontal parameters were not affected in the two groups. The CM group had a significantly lower pain, experienced less surgery time, and gained better aesthetics compared to the FGG group. CONCLUSION: CM appears to be a suitable substitute for FGG in procedures designed to increase keratinized tissue around teeth. It has remarkable benefits, such as acceptable keratinized tissue gain, less pain, less surgical chair time, and better aesthetics.

6.
Photodiagnosis Photodyn Ther ; 15: 213-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27435750

RESUMO

INTRODUCTION: Photodynamic therapy is an innovative treatment modality, which is appropriate for tumor detection and for the treatment of cancer as well as nontumoral diseases, such as psoriasis (2), bacterial and viral eradication. MATERIAL AND METHOD: Effect of two photosensitizer (toluidine blue O (TBO) and Radachlorin was investigated on Staphylococcus Aureus ATCC 25923 (American Type Culture Collection) and Escherichia coli (ATCC 25922). RESULTS: PDI by TBO caused S. aureus 5.83 log10 killing (P.Value<0.0001) and reduce 0.08 log 10 in E. coli (P.Value=0.321). PDI by Radachlorin(®) reduce 0.17 log 10 in E. coli (P.Value<0.0001) and S. aureus showed 6.1 log 10 colony count reduction. CONCLUSION: Within the limitation of this in vitro study, we can conclude that both PS have the same effect on S. aureus and E. coli with good inhibition effect on S. aureus and partial inhibition effect E. coli.


Assuntos
Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fotoquimioterapia/métodos , Porfirinas/administração & dosagem , Staphylococcus aureus/efeitos dos fármacos , Cloreto de Tolônio/administração & dosagem , Proliferação de Células/fisiologia , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Combinação de Medicamentos , Quimioterapia Combinada/métodos , Escherichia coli/fisiologia , Humanos , Luz , Fármacos Fotossensibilizantes/administração & dosagem , Especificidade da Espécie , Staphylococcus aureus/fisiologia
7.
J Lasers Med Sci ; 5(2): 82-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25653804

RESUMO

INTRODUCTION: The aim of this study is the evaluation of the effect of Antimicrobial Photodynamic Therapy with Radachlorin on Staphylococcus aureus and Escherichia coli. New windows are open in the antimicrobial field so-call Photodynamic therapy that incorporates a nonpoisonous photosensitizer (PS) with innocuous special wavelength photons to excite the PS. METHODS: Two strains of bacteria used in this study were Methicillin resistant Staphylococcus aureus (ATCC 33591; PTCC 1764) and Escherichia coli (ATCC 25922; PTCC1399). Concentrations of 0.2 ml of Radachlorin® were applied on 0.2 ml of bacterial suspensions and placed in a 48-well microtiter plate. The following groups were used: (I) L- PS- (no laser, no photosensitizer), (II) L-PS+ (treated only with PS), (III) L+ PS- (treated only with laser) and (IV) L+ PS+ (treated with laser and PS: photodynamic therapy group). Aliquots of bacterial suspensions were sensitized with Radachlorin® for 15 minutes in the dark at room temperature and then bacterial suspensions in group III and IV were irradiated with 210 mW (power density) and 12 J/cm2 (energy density) on continuous mode. RESULTS: This study showed that photodynamic therapy reduces 0.14 log 10 in E.Coli (group IV) and there were significant differences for group IV (P<0.01). Photodynamic therapy in S.Aureus showed 6.28 log 10 colony count reduction (group IV) and there were highly significant differences in Photodynamic therapy group (P<0.0001). CONCLUSION: Radachlorin® have bactericidal effect on S.aureus (6.28 log 10) and bacteriostaticeffect on E.coli (0.14 log 10).

8.
J Dent (Tehran) ; 10(4): 351-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24396354

RESUMO

OBJECTIVE: The aim of this randomized controlled clinical trial was to investigate the effect of a new Iranian toothpaste and a commercially available toothpaste containing desensitizing agent (5% potassium nitrate) on dentine hypersensitivity in a 24-week study. MATERIALS AND METHODS: Fifty healthy volunteers, who had at least two sensitive root surfaces, completed the study period. The participants were randomly given one of the two toothpastes; Iranian (antihypersensitive Pooneh) or commercially available (fresh mint Sensodyne) toothpaste. Visual analogue scales (VASs) indicating the intensity of tooth hypersensitivity responding to tactile, airblast and cold-water stimuli were examined at baseline and weeks 2, 4, 12 and 24. RESULTS: Overall, VAS scores for tactile, airblast, and cold-water tests significantly reduced compared with the baseline in both groups (all P values <0.001). However, there was no significant difference between the two groups regarding the measured parameters. CONCLUSION: This study demonstrated that the Iranian dentifrice (antihypersensitive Pooneh) was as effective as the commercially available one (fresh mint Sensodyne) in reducing tooth hypersensitivity.

9.
Iran J Pediatr ; 20(2): 174-80, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23056700

RESUMO

OBJECTIVE: Bruxism is defined as the habitual nonfunctional forceful contact between occlusal tooth surfaces. The aim of this study was to determine the prevalence of bruxism and correlated factors in children referred to dental schools of Tehran, based on Parent's report. METHODS: This cross-sectional descriptive study was conducted on 600 4-12 year-old children with a mean age of 7.4±2.4 years, who were referred to four dental schools in Tehran. After collecting information with questionnaire filled out by parents, χ(2), Fisher Test, Mann-Whitney and t-Test were used to analyze the data. FINDINGS: The prevalence of bruxism was 26.2%. Bruxism begun in average at the age of 4.9±2 years. Also it occurred 2.6 times more in children who had a family history of bruxism (father-mother), compared to children who didn't have such a history. 87% of children with bruxism had a history of distressing events in their life, and 13% of children with bruxism did not report any history of distressing events in their life. In this study most common oral habit was nail biting. In study of parasomnias, drooling was the most, and snoring the least reported sleep disorder. Bruxism in children with drooling was twice more than in other children. The prevalence of bruxism in children with temporomandibular disorder was 63.6% and in children without TMD was 24.7%. CONCLUSION: Based on Parent's report, 26.2% of children showed bruxism and there was a significant relation between bruxism and mother's job, family history, distressing event in life, parasomnias, especially drooling and sleep walking, TMD, hyperactivity, depression, acrophobia and lygophobia.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...