256 research outputs found
Avaliação de Modelos de Misturas Aplicado à Classificação de Impressões Digitais Segundo a Arquitetura PCASYS
Atualmente, os sistemas de reconhecimento biométrico tem alcançado grande desenvolvimento e vem sendo usados em diversas áreas como a comercial, a financeira e de segurança. No caso específico do reconhecimento de impressões digitais os sistemas automáticos de identificação (AFIS) são capazes de identificar indivíduos localizados em grandes bancos de dados, lidando com dezenas de milhões de amostras, as que originam um custo computacional bastante elevado. Assim, a classificação de impressões digitais é um problema importante de ser tratado uma vez que diminui o tempo de busca por um indivíduo, reduzindo o espaço de busca a um determinado subgrupo.
No presente trabalho busca-se avaliar se, para a arquitetura de classificação de impressões digitais conhecida como PCASYS (Pattern-Level Classification Automation System), é possível assumir que as classes podem ser modeladas por funções de densidade de probabilidade gaussiana e que podem alcançar resultados de classificação comparáveis com os obtidos com técnicas mais amadurecidas, como as baseadas em redes neurais. Para isto, empregou-se os modelos de misturas gaussianas (GMM) com abordagens supervisionada e não-supervisionada na estimativa de parâmetros.
Os resultados foram avaliados comparando as taxas de erro de classificação obtidos neste trabalho frente aos resultados alcançados com outras técnicas no estado da arte; assim mesmo, analisou-se estatisticamente os parâmetros dos modelos de misturas gaussianas estimados usando teste de hipótese e entropia mútua. Os testes foram feitas usando o banco de imagens de impressões digitais número 4 do National Institute of Standard and Technology (NIST) considerando os problemas de classificação de 4 e 5 classes e as distribuições natural e balanceada
Ranibizumab for the treatment of retinopathy of prematurity: systematic review and meta-analysis
Anti-VEGF drugs like ranibizumab can be used to treat retinopathy of prematurity (ROP) by halting the formation of abnormal blood vessels, or lasers can be used to burn the edges of the retina where these vessels are present. The objective is to compare the efficacy for ROP between ranibizumab and laser therapy. Material and methods: Electronic searches will be carried out in medical databases with key words and controlled vocabulary terms. Randomized controlled trials (RCT) will be assessed. The primary outcome will be the full ROP regression. Two reviewers will extract the data using predefined forms and, to assess the quality of the study, we will use RoB 2.0, the tool for randomized controlled trials developed by the Cochrane Collaboration. We used a combination of the inverse-variance approach and random-effects models for the meta-analysis. Results: The eyes of 182 preterm infants who had ranibizumab treatment were assessed in a total of 364 eyes, and 135 infants received laser therapy. The follow-up period was between 6 and 24 months. Ranibizumab was not associated with greater regression of ROP compared to laser therapy in preterm infants (RR: 1.09, CI 95%: 0.95–1.24; p: 0.22). Also, ranibizumab was not associated with recurrence of ROP compared to laser therapy in preterm infants (RR: 3.77, CI 95%: 0.55–25.81; p: 0.22). Conclusions: The efficacy of ranibizumab compared to laser is very uncertain in terms of ROP regression and decreased ROP recurrence in preterm infants. Systematic Review Registration: identifier PROSPERO (CRD42022324150)Revisión por pare
Desorden linfoproliferativo de células t cd4 asociado al virus epstein barr primario de oreja: CD4 T cell lymphoproliferative disorder associated with the primary ear epstein barr virus
Two cutaneous entities related to EBV are recognized in the 2016 World Health Organization (WHO) classification: Hydroa vacciniforme–like lymphoproliferative disorder and Extranodal NK/T-cell lymphoma, nasal type. Rare cases of EBV primary cutaneous CD8-positive T lymphomas have been reported. These lymphoid proliferations do not fit into any of the two classical EBV-related lymphomas .We report a unique case of an Epstein-Barr Virus-associated Primary Cutaneous –CD4-positive T-Cell Lymphoproliferative Disorder affecting the bilateral ears with indolent outcome and subsequent relapse on the tongue and trunk skin. Key words: EBV; CD4; lymphoma; Skin; Ear. (source: MeSH NLM)
DOI: 10.25176/RFMH.v18.n2.1289En la clasificación de la Organización Mundial de la Salud (OMS) del 2016 se reconocen dos entidades cutáneas relacionadas con el EBV: el desoerden linfoproliferativo tipo Hydroa vaciniforme y el linfoma extraganglionar NK / T de células nasales. Se han informado casos raros de linfoma T primario CD8 cutáneo EBV positivo. Estas proliferaciones linfoides no encajan en ninguno de los dos linfomas clásicos relacionados con EBV . Presentamos un caso único de un trastorno linfoproliferativo de células T primario cutáneo-CD4-cutáneo asociado con el virus de Epstein-Barr que afecta los oídos bilaterales con curso indolente y recaída posterior en la piel de la lengua y el tronco. Palabras clave: EBV; CD4; Linfoma; Piel; Oreja. (fuente: DeCS BIREME)
DOI: 10.25176/RFMH.v18.n2.128
EVALUACIÓN DE LA ESTRUCTURA ESTRATÉGICA EN LAS PYMES DEL SECTOR METALMECÁNICO EN EL DISTRITO DE LOS OLIVOS 2019-2021
"This publication describes the situation of micro and small
companies (pymes) in the metalworking sector in the Los Olivos
district. Currently there are various studies on the situation of
pymes and they argue the importance of the development and
growth of these companies at the business level to improve the
performance of your organization. According to the study carried
out at the demographic, economic, social, educational level; the
reality in which they carry out their activities was known. 62%
of the current population is made up of young people and adults.
Households have access to means of communication such as
television, internet and telephony. Pymes carry out activities
under artisanal methods.
The lack of financial support from the state or private
entrepreneurs to carry out research & development (I&D) activities in the metalworking sector prevents them from
innovating products and being more competitive.
Based on the results, it was proposed to create an Association of
Entrepreneurs of the Infantas Industrial Park in the Los Olivos
district (AMPEI), a steering committee and statutes; develop
training programs; find entities that finance pymes with
competitive interest rates.
Actividad antimicrobiana de metabolitos secundarios de Aspergillus fumigatus sensu stricto sobre cepas clínicas de Staphylococcus aureus y Streptococcus pneumoniae
Introduction. The antibiotic resistance of Gram positive bacteria is a serious public health problem where some palliative measures can be found in the antimicrobial principles of filamentous fungi. Objective. To evaluate the antimicrobial activity of secondary metabolites of a clinical isolation of Aspergillus fumigatus on clinical strains of Staphylococcus aureus and Streptococcus pneumoniae. Methods. The liquid fermentation of A. fumigatus was carried out in a liquid broth sulfate, potato and dextrose; using ethyl acetate for the extraction of secondary metabolites. The antimicrobial activity considered as a halo greater than 6 mm was evaluated using the diffusion disk methodology. Results. A mean of 24,02 ± 2,51 mm and 23,62 ± 4,68 mm was obtained on sensitive and resistant Staphylococcus aureus, respectively. For Streptococcus pneumoniae sensitive and non-susceptible, the means were 25,82 ± 4,05 mm and 26,5 ± 5,39 mm, respectively. Conclusions. The crude extract of A. fumigatus has secondary metabolites of alkaloid nature and unsaturated sterols with antimicrobial activity.Introducción. La resistencia a los antibióticos de bacterias Gram positivas es un grave problema de salud pública donde algunas medidas paliativas pueden encontrarse en los principios antimicrobianos de hongos filamentosos. Objetivo. Evaluar la actividad antimicrobiana de metabolitos secundarios de un aislamiento clínico de Aspergillus fumigatus sobre cepas clínicas de Staphylococcus aureus y Streptococcus pneumoniae. Métodos. La fermentación líquida de A. fumigatus se realizó en un caldo líquido sulfato, papa y dextrosa, utilizando acetato de etilo para la extracción de metabolitos. Mediante la metodología de disco difusión se evaluó la actividad antimicrobiana considerada como un halo mayor de 6 mm. Resultados. Se obtuvo una media de 24,02 ± 2,51 mm y 23,62 ± 4,68 mm de halo de inhibición sobre Staphylococcus aureus sensible y resistente oxacilina, respectivamente. Para Streptococcus pneumoniae sensibles y no sensibles a penicilina las medias fueron de 25,82 ± 4,05 mm y 26,5 ± 5,39 mm, respectivamente. Conclusiones. El extracto crudo de A. fumigatus posee metabolitos secundarios de naturaleza alcaloide y esteroles insaturados con actividad antimicrobiana
Research training needs in Peruvian national TB/HIV programs
<p>Abstract</p> <p>Background</p> <p>There are few published reports of <it>research training </it>needs assessments and research training programs. In an effort to expand this nascent field of study and to bridge the gap between research and practice, we sought to systematically assess the research training needs of health care professionals working at Peruvian governmental institutions leading HIV and tuberculosis (TB) control and among senior stakeholders in the field.</p> <p>Methods</p> <p>Six institutional workshops were conducted with the participation of 161 mid-level health professionals from agencies involved in national HIV and TB control. At each workshop informants completed a structured questionnaire and participated in small and large group discussions. Additional data and institutional commitment was obtained through in-depth interviews from 32 senior managers and researchers from the Ministry of Health, academia and NGOs.</p> <p>Results</p> <p>Participants exhibited an overwhelming receptivity for additional research training, observing a gap between current levels of research training and their perceived importance. Specialized skills in obtaining funding, developing research protocols, particularly in operational, behavioral and prevention research were considered in greatest need. Beyond research training, participants identified broader social, economic and political factors as influential in infectious disease control.</p> <p>Conclusions</p> <p>The needs assessment suggests that future training should focus on operational research techniques, rather than on clinical skill building or program implementation only. Strengthening health systems not only requires additional research training, but also adequate financial resources to implement research findings.</p
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