Comparison of methods for the number recognition of sport players

Projecte final de carrera fet en col.laboració amb Université Catholique de Louvain. Ecole Polytechnique de Louvain.In a system of detection and recognition of players on a sport- el, the process of identifying numbers from a binary image is the last step. The identi cation is possible using the numbers of players jerseys that are obtained from images captured by a distributed set of cameras. The main problem to solve is that these pictures have di erent sizes and su er rotations and non-rigid deformations. Prior to this project were independently studied three methods to recognize numbers from the players jerseys. The good results obtained encouraged to use any of these methods in the system of recognition of athletes. The provided methods to obtain the image features are based on matching pursuit, local binary pattern and optical character recognition algorithms. The main objective of this project is justify which is the most appropriate method. But the fact that previous studies were independents involve that can not be made a direct comparison of their results. Therefore is necessary a fair comparison with common criteria. Get this fair comparison is result of working in an homogenous environment. This implies that all the methods have been tested with a set of common images and a common classi er, based on support vector machine. It has been trained with a set of pictures of a basketball match. The criteria taken into account have been the accuracy in the identi cation, obtained with the 10-fold cross-validacion, and the time needed by each method to identify a number. Once done the study, it has been concluded that the method that works with the optical character recognition is the most accurate and fastest. Although this method is the most susceptible to the rotation of images, so its need a normalization, clearly is the most e cient as for the identi cation of digits as to detect a false identi cation. The fact that the di erences between the three methods results are so wide, leads to be sure of the choice made. So clearly has been chosen the most e cient method to be used in the project, still in development, that detects, recognizes and tracks players on a sport- eld

Comparison of methods for the number recognition of sport players

Projecte final de carrera fet en col.laboració amb Université Catholique de Louvain. Ecole Polytechnique de Louvain.In a system of detection and recognition of players on a sport- el, the process of identifying numbers from a binary image is the last step. The identi cation is possible using the numbers of players jerseys that are obtained from images captured by a distributed set of cameras. The main problem to solve is that these pictures have di erent sizes and su er rotations and non-rigid deformations. Prior to this project were independently studied three methods to recognize numbers from the players jerseys. The good results obtained encouraged to use any of these methods in the system of recognition of athletes. The provided methods to obtain the image features are based on matching pursuit, local binary pattern and optical character recognition algorithms. The main objective of this project is justify which is the most appropriate method. But the fact that previous studies were independents involve that can not be made a direct comparison of their results. Therefore is necessary a fair comparison with common criteria. Get this fair comparison is result of working in an homogenous environment. This implies that all the methods have been tested with a set of common images and a common classi er, based on support vector machine. It has been trained with a set of pictures of a basketball match. The criteria taken into account have been the accuracy in the identi cation, obtained with the 10-fold cross-validacion, and the time needed by each method to identify a number. Once done the study, it has been concluded that the method that works with the optical character recognition is the most accurate and fastest. Although this method is the most susceptible to the rotation of images, so its need a normalization, clearly is the most e cient as for the identi cation of digits as to detect a false identi cation. The fact that the di erences between the three methods results are so wide, leads to be sure of the choice made. So clearly has been chosen the most e cient method to be used in the project, still in development, that detects, recognizes and tracks players on a sport- eld

Detection and expression analysis of tet (B) in Streptococcus oralis

Tetracycline resistance can be achieved through tet genes, which code for efflux pumps, ribosomal protection proteins and inactivation enzymes. Some of these genes have only been described in either Gram-positive or Gram-negative bacteria. This is the case of tet (B), which codes for an efflux pump and, so far, had only been found in Gram-negative bacteria. In this study, tet (B) was detected in two clinical Streptococcus oralis strains isolated from the gingival sulci of two subjects. In both cases, the gene was completely sequenced, yielding 100% shared identity and coverage with other previously published sequences of tet (B). Moreover, we studied the expression of tet (B) using RT-qPCR in the isolates grown with and without tetracycline, detecting constitutive expression in only one of the isolates, with no signs of expression in the other one. This is the first time that the presence and expression of the tet (B) gene has been confirmed in Gram-positive bacteria, which highlights the potential of the genus Streptococcus to become a reservoir and a disseminator of antibiotic resistance genes in an environment so prone to horizontal gene transfer as is the oral biofilm

Control by Fur of the nitrate respiration regulators NarP and NarL in Salmonella enterica

Anaerobic metabolism is controlled by several transcriptional regulators, including ArcA, Fnr, NarP, and NarL, with the Fnr and ArcA proteins sensitive to the cell’s redox status. Specifically, the two-component ArcAB system is activated in response to the oxidation state of membrane-bound quinones, which are the central electron carriers of respiration. Fnr, by contrast, directly senses cellular oxidation status through the [4Fe-4S] cluster present in its own structure. In this study, a third additional redox-associated pathway that controls the nitrate respiration regulators NarL and NarP was identified. The results showed that, in Salmonella enterica, the expression of these two transcriptional regulators is under the control of Fur, a metalloregulator that senses the presence of Fe2+ and regulates the homeostasis of this cation inside the cell. Thus, the Fur- Fe2+ complex increases the expression of narL and represses that of narP. Furthermore, studies of S. enteric mutants defective in the Fur-regulated sRNA RfrA and RfrB showed that those sRNA control both narP and narL expression. These results confirm Fur as a global regulator based on its involvement not only in iron uptake and detoxification but also in the control of nitrate/nitrite respiration by sensing cellular redox status. [Int Microbiol 2010; 13(1):33-39

Erythritol-enriched powder and oral biofilm regrowth on dental implants: an in vitro study.

BACKGROUND: Peri-implant mucositis and peri-implantitis are the main biological complications associated with dental implants. Since most authors agree that bacteria play a major etiological role, the main aims of this study were to determine if a formulation of erythritol and chlorhexidine applied with an air polishing system inhibits biofilm regrowth over dental implants and to compare the decontamination capacity of this therapy with that of mechanical removal by saline and gauze. MATERIAL AND METHODS: A multispecies biofilm (P. gingivalis, A. actinomycetemcomitans, F. nucleatum, A. naeslundii, V. parvula and S. oralis) was grown for 14 days on 52 dental implants in an artificial mouth. These implants were divided into three groups according to the applied treatment: 14 negative control (CON), 19 erythritol-chlorhexidine (ERY) and 19 gauze with saline (GAU) samples. Twelve dental implants from the ERY and GAU groups and 8 implants from the CON group were re-incubated for 7 additional days after treatment. The bacterial count was performed by quantitative polymerase chain reaction (qPCR) using propidium monoazide (PMA). A descriptive and bivariate analysis of the data was performed. RESULTS: The erythritol and chlorhexidine formulation significantly inhibited biofilm regrowth in comparison with the mechanical treatment (GAU), since a significant decrease in all the species was observed in the ERY group (except for Aggregatibacter actinomycetemcomitans). The antibiofilm and antibacterial capacity of the two active treatment groups (ERY and GAU) was similar for a 14 days multispecies in vitro biofilm, except for the lower count of A. naeslundii in the GAU group. CONCLUSIONS: The use of erythritol powder with chlorhexidine applied with an air polishing system reduces biofilm regrowth over dental implants when compared with mechanical removal by saline and gauze. This effect might be beneficial for patients included in peri-implant maintenance programs

Oral microbiota of adolescents with dental caries:A systematic review

Objective: This systematic review summarizes the current knowledge on the association between the oral microbiota and dental caries in adolescents. Design: An electronic search was carried out across five databases. Studies were included if they conducted research on generally healthy adolescents, applied molecular-based microbiological analyses and assessed caries status. Data extraction was performed by two reviewers and the Newcastle-Ottawa Scale was applied for quality assessment. Results: In total, 3935 records were reviewed which resulted in a selection of 20 cross-sectional studies (published 2005–2022) with a sample size ranging from 11 to 614 participants including adolescents between 11 and 19 years. The studies analyzed saliva, dental biofilm or tongue swabs with Checkerboard DNA-DNA hybridization, (q)PCR or Next-Generation Sequencing methods. Prevotella denticola, Scardoviae Wiggsiae, Streptococcus sobrinus and Streptococcus mutans were the most frequently reported species presenting higher abundance in adolescents with caries. The majority of the studies reported that the microbial diversity was similar between participants with and without dental caries. Conclusion: This systematic review is the first that shows how the oral microbiota composition in adolescents appears to differ between those with and without dental caries, suggesting certain taxa may be associated with increased caries risk. However, there is a need to replicate and expand these findings in larger, longitudinal studies that also focus on caries severity and take adolescent-specific factors into account.</p

Association of nine pathobionts with periodontitis in four South American and European countries.

peer reviewed[en] AIM: Our aim was to compare the prevalence and load of nine pathobionts in subgingival samples of healthy individuals and periodontitis patients from four different countries. METHODS: Five hundred and seven subgingival biofilm samples were collected from healthy subjects and periodontitis patients in Belgium, Chile, Peru and Spain. The prevalence and load of Eubacterium brachy, Filifactor alocis, Fretibacterium fastidiosum, Porphyromonas endodontalis, Porphyromonas gingivalis, Selenomonas sputigena, Treponema denticola, Tannerella forsythia and Treponema socranskii were measured by quantitative PCR. RESULTS: The association with periodontitis of all species, except for T. socranskii, was confirmed in all countries but Peru, where only P. endodontalis, P. gingivalis and T. denticola were found to be significantly associated. Moreover, most species showed higher loads at greater CAL and PPD, but not where there was BOP. Through Principal Component Analysis, samples showed clearly different distributions by diagnosis, despite observing a smaller separation in Peruvian samples. CONCLUSIONS: Unlike prevalence, relative load was found to be a reliable variable to discriminate the association of the species with periodontitis. Based on this, F. alocis, P. endodontalis, P. gingivalis, T. denticola and T. forsythia may be biomarkers of disease in Belgium, Chile and Spain, due to their significantly higher abundance in periodontitis patients

Impacte dels sistemes de reparació de lesions produïdes per agents alquilants en la virulència de Salmonella enterica ser. Typhimurium

Salmonella enterica ser. Typhimurium (S. Typhimurium) és un enterobacteri patogen que afecta a diverses espècies de mamífers i que generalment causa infeccions lleus, com gastroenteritis, si bé pot arribar a generar malalties sistèmiques, produint septicèmia i, fins i tot, la mort de l'hoste infectat.Com molts altres enterobacteris, el seu genoma codifica per proteïnes que permeten reparar les lesions alquilants en el DNA, les quals són causades quan agents alquilants, siguin procedents de l'ambient extern o bé originats pel propi metabolisme cel·lular, introdueixen grups alquil a les bases nitrogenades. Entre els gens que les codifiquen cal destacar ada, alkA, alkB i aidB, que componen l'anomenada resposta adaptativa a agents alquilants (resposta Ada); i ogt i tag, que desenvolupen funcions similars als anteriors però que no formen part de la resposta Ada. Altres sistemes de reparació més genèrics també intervenen en l'eliminació de lesions alquilants, essent particularment rellevants els gens que constitueixen les vies GGR (realitzada pel complex enzimàtic) i TCR (dirigida a les zones transcripcionalment actives i portada a terme per la proteïna Mfd en conjunció amb el complex UvrABC o amb MutSL) de la reparació per escissió de nucleòtids (NER). Entre tots ells formen un grup molt ampli d'activitats de reparació que permeten reconèixer la gran varietat de dianes que poden ser generades per agents alquilants.Per comprendre el paper de cada un d'aquests gens durant el transcurs del procés infectiu es van construir soques defectives en un o en varis d'aquests gens. Seguidament es va analitzar la capacitat de supervivència de cadascuna d'elles al ser exposades a diferents agents alquilants. Malgrat de disposar de tantes proteïnes de reparació d'alquilacions, en la majoria de casos la manca d'una o vàries d'elles va suposar una disminució de la viabilitat cel·lular quan aquestes soques creixien en presència d'agents alquilants. A continuació es van realitzar assajos de competitivitat en ratolins BALB/c per a determinar la capacitat infectiva de cada un dels mutants construïts. Els resultats experimentals obtinguts demostren que, fins i tot en les soques defectives en múltiples gens, la manca de la majoria d'aquestes proteïnes no suposa una disminució de la capacitat infectiva de S. Typhimurium ja que, malgrat les dades recollides prèviament a partir dels assajos in vitro, tan sols el mutant UA1869, deficient en els gens ada, ogt, tag, uvrA i mfd, va presentar una reducció de la competitivitat en relació a la soca salvatge. Per consegüent, la concentració d'agents alquilants generats a l'organisme deu ser menor a la utilitzada durant els assajos in vitro, de manera que la conservació dels gens de reparació d'alquilacions a S. Typhimurium podria ser deguda a la supervivència fora de l'hoste.El fet que la disminució de la competitivitat s'hagi donat en la soca UA1869 i no en altres mutants, alguns amb un nombre major de mutacions, però on les funcions absents no eren tan diverses, fa pensar en l'existència d'activitats redundants entre diferents sistemes de reparació, de manera que la manca de proteïnes de reparació d'un mecanisme podria ser compensada per altres pertanyents a sistemes amb una activitat aparentment diferent.Salmonella enterica ser. Typhimurium (S. Typhimurium) is an enteropathogen able to infect several mammalian species, generally causing mild diseases, such as gastroenteritis, although it can also become a systemic infection, producing septicaemia and even the death of the infected host.Like other enterobacteria, the genome of S. Typhimurium codes for alkylation damage repair proteins. This kind of damage appears when alkylating agents, which are present in the environment or are produced endogenously as byproducts of normal metabolism, introduce alkyl groups in the DNA bases. Some of the most important genes coding for these proteins are ada, alkA, alkB and aidB, which generate the adaptive response to alkylation damage (known as the Ada response); and ogt and tag, which are not included in this response but possess similar functions. Other repair systems with a wider range of activities can also repair alkylation damage, being especially important the genes belonging to the global genome repair (GGR, which is carried out by the UvrABC enzymatic complex) and the transcription-coupled DNA repair (TCR, focused on the transcriptionally active genes and directed by the Mfd protein, which recruits the UvrABC or the MutSL complexes) pathways of the nucleotide excision repair system (NER). Altogether compound a large variety of repair activities which allow the recognition of a broad diversity of targets generated by alkylating agents.In order to establish the role of each of these genes and the consequences of their lack during the infection process, strains defective in one or several of them were constructed. Afterwards, each strain was treated with alkylating agents to analyze its survival. Although S. Typhimurium possesses so many alkylation damage repair proteins, in most strains the survival decreased due to the absence of just one or some of those proteins. Moreover, competitive assays using BALB/c mice were performed to determine the fitness of each strain. The results show that, even in those strains defective in several genes, the in vivo fitness of S. Typhimurium is not affected by the lack of most of the alkylation damage repair proteins studied, since only the strain UA1869 defective in the ada, ogt, tag, uvrA, and mfd genes presented a reduction of its virulence when it was orally inoculated. Therefore, the amount of alkylating agents generated in the organism might be lower than that used in the in vitro assays. Thus, the evolutionary conservation of the alkylation damage repair genes in S. Typhimurium may be due to survival outside the host.The fact that the fitness decreased in the UA1869 strain and not in other mutants, some of them defective in a larger number of genes, suggests the existence of certain overlap between different repair systems. Thus, the absence of some repair proteins might be compensated by other belonging to other systems apparently different

Comparison of methods for the number recognition of sport players

Projecte final de carrera fet en col.laboració amb Université Catholique de Louvain. Ecole Polytechnique de Louvain.In a system of detection and recognition of players on a sport- el, the process of identifying numbers from a binary image is the last step. The identi cation is possible using the numbers of players jerseys that are obtained from images captured by a distributed set of cameras. The main problem to solve is that these pictures have di erent sizes and su er rotations and non-rigid deformations. Prior to this project were independently studied three methods to recognize numbers from the players jerseys. The good results obtained encouraged to use any of these methods in the system of recognition of athletes. The provided methods to obtain the image features are based on matching pursuit, local binary pattern and optical character recognition algorithms. The main objective of this project is justify which is the most appropriate method. But the fact that previous studies were independents involve that can not be made a direct comparison of their results. Therefore is necessary a fair comparison with common criteria. Get this fair comparison is result of working in an homogenous environment. This implies that all the methods have been tested with a set of common images and a common classi er, based on support vector machine. It has been trained with a set of pictures of a basketball match. The criteria taken into account have been the accuracy in the identi cation, obtained with the 10-fold cross-validacion, and the time needed by each method to identify a number. Once done the study, it has been concluded that the method that works with the optical character recognition is the most accurate and fastest. Although this method is the most susceptible to the rotation of images, so its need a normalization, clearly is the most e cient as for the identi cation of digits as to detect a false identi cation. The fact that the di erences between the three methods results are so wide, leads to be sure of the choice made. So clearly has been chosen the most e cient method to be used in the project, still in development, that detects, recognizes and tracks players on a sport- eld

Detection and expression analysis of tet (B) in Streptococcus oralis

Tetracycline resistance can be achieved through tet genes, which code for efflux pumps, ribosomal protection proteins and inactivation enzymes. Some of these genes have only been described in either Gram-positive or Gram-negative bacteria. This is the case of tet (B), which codes for an efflux pump and, so far, had only been found in Gram-negative bacteria. In this study, tet (B) was detected in two clinical Streptococcus oralis strains isolated from the gingival sulci of two subjects. In both cases, the gene was completely sequenced, yielding 100% shared identity and coverage with other previously published sequences of tet (B). Moreover, we studied the expression of tet (B) using RT-qPCR in the isolates grown with and without tetracycline, detecting constitutive expression in only one of the isolates, with no signs of expression in the other one. This is the first time that the presence and expression of the tet (B) gene has been confirmed in Gram-positive bacteria, which highlights the potential of the genus Streptococcus to become a reservoir and a disseminator of antibiotic resistance genes in an environment so prone to horizontal gene transfer as is the oral biofilm