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1.
Poly(vinyl alcohol)-Based Electrospun Nanofibers with Improved Antimicrobial Activity
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Machado, Paola A. P.
; Fraga, Gabriel N.
; Medeiros, Alessandra R.
; Pellá, Michelly C. G.
; Colauto, Nelson B.
; Linde, Giani A.
; Cavalheiro, Fernando N.
; Faria, Maria G. I.
; Dragunski, Douglas C.
; Caetano, Josiane
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
Electrospinning was used to produce poly(vinyl alcohol) (PVA)-based nanofibers containing nerolidol (NER) as the antimicrobial agent. The scanning electron microscopy results indicated the formation of homogeneous fibers in the absence of NER. However, its incorporation into the fiber prevented the complete solvent evaporation, ultimately leading to the coalescence of the fibers. It became more evident as the amount of NER increased from 0 to 50% m/v. The incorporation of NER also decreased the crystallinity of the fibers from 10 to ca. 6.5%. However, this decrease was not proportional to the concentration of NER. The contact angle results confirmed the presence of NER molecules on the surface of the fibers especially due to the increase of the contact angle from 0 (PVA/NER0) to 27.8º (PVA/NER50). The fibrous mats exhibited good antimicrobial activity, being even more efficient than the control in some cases, suggesting their potential for wound-dressing purposes.
2.
Prevención de eventos de superpropagación de COVID-19 en autobuses que transportaron pacientes presintomáticos
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Ochoa-Hein, Eric
; Huertas-Jiménez, Martha A.
; Chávez-Ríos, Alma R.
; Haro-Osnaya, Anabel
; De Paz-García, Roxana
; Colín-Ugalde, Alberto G.
; Leal-Morán, Patricia E.
; Vargas-Fernández, Abril T.
; Vargas-Fernández, José F.
; González-González, Ricardo
; Rajme-López, Sandra
; González-Lara, María F.
; Ponce-De León, Alfredo
; Sifuentes-Osornio, José
; Galindo-Fraga, Arturo
.
Resumen Introducción: Ha ocurrido superpropagación de COVID-19 cuando individuos sintomáticos sin uso de cubrebocas abordaron autobuses. Objetivo: Reportar el riesgo de superpropagación cuando individuos presintomáticos abordaron autobuses junto con pasajeros no vacunados, pero se mantuvieron intervenciones preventivas no farmacológicas. Métodos: Estudio prospectivo de personal de salud transportado durante dos semanas en autobuses a un centro de vacunación contra COVID-19. Fue obligatorio llevar ventanas abiertas, uso correcto de cubrebocas y exclusión de personas con síntomas. La vigilancia prospectiva identificó a trabajadores con COVID-19 los 14 días siguientes a la vacunación. Cada pasajero asintomático de autobuses donde se detectaron casos fue vigilado durante un periodo similar. Los resultados de tamizaje voluntario estuvieron disponibles para los trabajadores que se realizaron prueba el mes previo o el siguiente a la vacunación. Resultados: 1879 trabajadores abordaron 65 autobuses. El tiempo a bordo varió de tres a ocho horas. Veintinueve casos de COVID-19 y cuatro casos asintomáticos fueron identificados entre 613 pasajeros de 21 autobuses. La mediana de tiempo entre la vacunación y el inicio de síntomas de COVID-19 fue de seis días. Fue identificado un caso de transmisión sospechada en autobús. Conclusiones: Las intervenciones preventivas no farmacológicas estrictas redujeron sustancialmente el riesgo de superpropagación de COVID-19 en autobuses ocupados por individuos presintomáticos.
Abstract Introduction: COVID-19 superspreader events have occurred when symptomatic individuals without wearing face masks boarded buses. Objective: To report the risk of superspreader events when presymptomatic individuals boarded buses together with unvaccinated passengers, but with non-pharmacological preventive interventions being maintained. Methods: Prospective study of health personnel transported in buses to a COVID-19 vaccination center for two weeks. Open windows, correct use of face masks and exclusion of symptomatic individuals were mandatory. Prospective surveillance identified workers with COVID-19 within 14 days after vaccination. Each asymptomatic passenger of buses where cases were identified was monitored for a similar time period. Voluntary screening results were available for workers who were tested in the month before or after vaccination. Results: 1,879 workers boarded 65 buses. On-board time ranged from three to eight hours. Twenty-nine cases of COVID-19 and four asymptomatic cases were identified among 613 passengers of 21 buses. Median time between vaccination and COVID-19 symptoms onset was six days. One case of suspected transmission on a bus was identified. Conclusions: Strict nonpharmacological preventive interventions substantially reduced the risk of COVID-19 superspreader events in buses boarded by presymptomatic individuals.
https://doi.org/10.24875/gmm.21000772
23 downloads
3.
Effect of pH level and calcination on the production of calcium phosphates by acidic route of wet precipitation
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Neves, J. G.
; Navarro da Rocha, D.
; Lopes, C. C.
; Prado da Silva, M. H.
; Sinhoreti, M. A. C.
; Correr-Sobrinho, L.
; Fraga, M. A. A.
; Correr, A. B.
.
Abstract Multiphasic calcium phosphate powders were synthesized by the acidic route, using lactic acid as a chelating agent that allows the production of a stable and rich solution of calcium and phosphate ions at room temperature. After pH adjusting, without varying the concentrations of precursor solution, XRD and FTIR analyses showed different CaP phases before and after heat treatment at 1000 °C. At pH 5, brushite plate-like particles were produced, while at higher pH levels (7 to 12) nano-hydroxyapatite particles were formed. After the calcination process, partial and total decomposition of hydroxyapatite in the β-TCP phase was explained by XRF analysis due to the calcium-deficient hydroxyapatite of synthesized samples at pH 7 and 10. This work presents an important method to synthesize any desired CaP phase compositions by varying the pH level and subsequently performing heat treatment, which has a direct effect on morphology, crystallinity, and formation of different CaP powders.
https://doi.org/10.1590/0366-69132021673822965
262 downloads
4.
ALTERNATIVES FOR THE PRODUCTION OF LEVULINIC ACID OBTAINED FROM BIOMASS
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Santos, Lucas A. dos
; Fraga, Gabrielle das V.
; Pontes, Danilo Aguiar
; Campos, Leila M. A.
; Pontes, Luiz A. M.
; Teixeira, Leonardo S. G.
.
Levulinic acid is a reactive polar organic compound deemed as a building block for several products with relevant applications, replacing traditional substances in the petrochemical industry. Considered a platform molecule, levulinic acid is industrially produced from the acid hydrolysis of biomass - mainly plant-based - using hydrochloric or sulfuric acid in homogenous catalysis. However, considering the World Market for levulinic acid is expected to reach US$ 71.9 million in 2027, growing annually at 14.1%, and its applications in agriculture, pharmaceuticals, plasticizers, cosmetics, and food additives, the development of alternative production processes is sought. Hence, a survey was performed on publications considering the alternatives for biomass-based levulinic acid production processes: I) alternative homogenous catalysts to avoid using noble materials in the reactor; II) heterogeneous catalysis to facilitate and reduce the catalyst’s separation and recovery costs; III) ionic liquids, exploiting their high solvency, stability, and catalytic capacity. Additionally, biomass alternatives for obtaining levulinic acid are presented, showing that other agricultural residues and animal biomass options are being considered, targeting process flexibilization while reducing costs and producing derivatives at more competitive prices. Thus, it can be stated that levulinic acid is an important platform molecule for biorefineries’ economics, replacing fossil fuels with renewable raw materials.
5.
PERSPECTIVAS DE MERCADO E DESAFIOS DA PRODUÇÃO DO ÁCIDO ITACÔNICO A PARTIR DE BIOMASSA
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Fraga, Gabrielle das V.
; Ruy, Alisson D. S.
; Pontes, Luiz A. M.
; Campos, Leila M. A.
; Teixeira, Leonardo S. G.
.
Itaconic acid (IA) is a very promising platform molecule due to the possibility of it being used to obtain products such as methyl methacrylate and synthetic latex, with the prospect that its global market will grow at an average annual rate of 2.8% (CAGR) from 2021 to 2026, exceeding US$ 116.6 million in sales. The main technological route used to obtain itaconic acid is fermentation using different strains of Aspergillus terreus fungi. The main advancements are related to genetic engineering, as Aspergillus terreus is the most tolerant of the microorganisms employed in the process synthesis and optimization. The main substrate used is glucose (52%), followed by glycerol (25%). Among the results presented in this paper, the best production was achieved using Ustilago maydis, with 220 g L-1 of IA, yielding 0.33 g g-1, using glucose as a carbon source. Moreover, it is necessary to continue optimizing the biological process of IA production, since it is a platform molecule with major economic potential.
https://doi.org/10.21577/0100-4042.20170573
854 downloads
6.
Clinical and Epidemiological Characteristics of Patients Diagnosed with COVID-19 in a Tertiary Care Center in Mexico City: A Prospective Cohort Study
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Ortiz-Brizuela, Edgar
; Villanueva-Reza, Marco
; González-Lara, María F.
; Tamez-Torres, Karla M.
; Román-Montes, Carla M.
; Díaz-Mejía, Bruno A.
; Pérez-García, Esteban
; Olivas-Martínez, Antonio
; Rajme-López, Sandra
; Martinez-Guerra, Bernardo A.
; León-Cividanes, Nereyda A. de
; Fernández-García, Oscar A.
; Guerrero-Torres, Lorena
; Torres-González, Lorena
; Carrera-Patiño, Fabián A.
; Corral-Herrera, Ever A.
; Hernández-Alemón, Aldo N.
; Tovar-Vargas, Maria de los Ángeles
; Serrano-Pinto, Yamile G.
; Espejo-Ortiz, Cristian E.
; Morales-Ortega, María de la L.
; Lozano-Cruz, Óscar A.
; Cárdenas-Fragoso, José L.
; Vidal-Mayo, José de J.
; Hernández-Gilsoul, Thierry
; Rivero-Sigarroa, Eduardo
; Domínguez-Cherit, Guillermo
; Cervantes-Villar, Luz E.
; Ramos-Cervantes, Maria del P.
; Ibarra-González, Violeta
; Calva-Mercado, Juan J.
; Sierra-Madero, Juan G.
; López-Íñiguez, Álvaro
; Ochoa-Hein, Eric
; Crabtree-Ramírez, Brenda E.
; Galindo-Fraga, Arturo
; Guerrero-Almeida, María de L.
; Ruiz-Palacios, Guillermo M.
; Gulías-Herrero, Alfonso
; Sifuentes-Osornio, José
; Kershenobich-Stalnikowitz, David
; Ponce-de-León, Alfredo
.
ABSTRACT Background: Regional information regarding the characteristics of patients with coronavirus disease (COVID)-19 is needed for a better understanding of the pandemic. Objective: The objective of the study to describe the clinical features of COVID-19 patients diagnosed in a tertiary-care center in Mexico City and to assess differences according to the treatment setting (ambulatory vs. hospital) and to the need of intensive care (IC). Methods: We conducted a prospective cohort, including consecutive patients with COVID-19 from February 26, 2020 to April 11, 2020. Results: We identified 309 patients (140 inpatients and 169 outpatients). The median age was 43 years (interquartile range, 33-54), 59.2% men, and 18.6% healthcare workers (12.3% from our center). The median body mass index (BMI) was 29.00 kg/m2 and 39.6% had obesity. Compared to outpatients, inpatients were older, had comorbidities, cough, and dyspnea more frequently. Twenty-nine (20.7%) inpatients required treatment in the IC unit (ICU). History of diabetes (type 1 or 2) and abdominal pain were more common in ICU patients compared to non-ICU patients. ICU patients had higher BMIs, higher respiratory rates, and lower room-air capillary oxygen saturations. ICU patients showed a more severe inflammatory response as assessed by white blood cell count, neutrophil and platelet count, C-reactive protein, ferritin, procalcitonin, and albumin levels. By the end of the study period, 65 inpatients had been discharged because of improvement, 70 continued hospitalized, and five had died. Conclusions: Patients with comorbidities, either middle-age obese or elderly complaining of fever, cough, or dyspnea, were more likely to be admitted. At admission, patients with diabetes, high BMI, and clinical or laboratory findings consistent with a severe inflammatory state were more likely to require IC.
https://doi.org/10.24875/ric.20000211
533 downloads
7.
FUNCTIONALIZED GRAPHENE-BASED MATERIALS AS INNOVATIVE ADSORBENTS OF ORGANIC POLLUTANTS: A CONCISE OVERVIEW
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Brazilian Journal of Chemical Engineering
- Métricas do periódico
ABSTRACT The functionalization of graphene nanosheets is the cutting edge of materials sciences nowadays. Such research promotes the development of innovative, low cost and highly capable sorbents. This review article aims to assemble the available information on functionalized graphene used for the adsorption of organic pollutants and establishes a critical comparison between the data reported in the literature. Various optimal experimental conditions (pH, temperature, contact time, adsorbent dosage) and adsorbent characterization methods (FTIR, Raman, XPS spectra, XRD, TEM and AFM) have been listed to enlighten adsorption mechanisms, capacity and limiting aspects. Moreover, adsorption isotherms, kinetics and thermodynamic data of different functionalized graphene-based materials towards a wide range of organic pollutants were analyzed and tabulated. In each evaluation topic, environmental and human health protection is subject for discussion, as well as the scientific breakthrough works available in high impact journals in the field.
https://doi.org/10.1590/0104-6632.20190361s20180283
6897 downloads
8.
Pseudotumor cerebri in childhood and adolescence: data from a specialized service
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Balbi, Gabriela G. M.
; Matas, Sandro L.
; Len, Claudio A.
; Fraga, Melissa M.
; Sousa, Iggor O.
; Terreri, Maria Teresa
.
RESUMO Relatar os casos de crianças e adolescentes com diagnóstico de pseudotumor cerebral com ou sem doença reumática. Métodos: Estudo retrospectivo através de revisão de prontuários, 29 pacientes com idade até 18 anos e diagnóstico de pseudotumor, atendidos nos ambulatórios de Reumatologia Pediátrica e Neurologia de um hospital terciário, registrados até dezembro de 2016. Resultados: Dentre os 29 pacientes com diagnóstico de pseudotumor cerebral, 51,7% eram meninas. A média de idade de aparecimento dos sintomas foi de 12,3 anos. Em relação à etiologia do pseudotumor cerebral, em 18 pacientes (62%) foi possível identificar uma causa, sendo o diagnóstico de doença reumática associada em quatro desses casos. Cefaléia foi o sintoma mais frequente (69%), e a medicação mais utilizada foi a acetazolamida (69%). Dois pacientes evoluíram para cegueira e 10 ainda se encontram em seguimento ambulatorial. Conclusão: Concluímos que, apesar de raro, o diagnóstico de pseudotumor cerebral deve ser considerado em crianças com cefaleia, principalmente nos pacientes com doença reumática.
ABSTRACT Objective: To report cases of children and adolescents diagnosed with pseudotumor cerebri associated or not with rheumatic disease. Methods: This was a retrospective study based on medical reports of 29 patients, up to 18 years of age and diagnosed with pseudotumor cerebri, followed up in the Pediatric Rheumatology and Neurology outpatient clinics of a tertiary hospital, until December 2016. Results: Among the 29 patients diagnosed with pseudotumor cerebri, 51.7% were girls and the mean age at the disease onset was 12.3 years. In 18 patients (62%) where an etiology was found, four were associated with a rheumatic disease. The most common symptom was headache (69%) and acetazolamide was the most used medication (69%). Two patients developed blindness and 10 are still being followed up. Conclusion: Although rare, pseudotumor cerebri should be considered in children with headaches, especially in patients with rheumatic disease.
https://doi.org/10.1590/0004-282x20180131
1968 downloads
9.
BsmI polymorphism in the vitamin D receptor gene is associated with 25-hydroxy vitamin D levels in individuals with cognitive decline
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Oliveira, Ana Carolina R. de
; Magalhães, Carolina A.
; Loures, Cristina M. G.
; Fraga, Vanessa G.
; Souza, Leonardo C. de
; Guimarães, Henrique C.
; Cintra, Marco T. G.
; Bicalho, Maria A.
; Sousa, Maira C. R.
; Silveira, Josianne N.
; Silva, Ieda F. O.
; Caramelli, Paulo
; Carvalho, Maria G.
; Gomes, Karina B.
.
RESUMO Idosos apresentam risco elevado de desenvolverem deficiência de Vitamina D (VitD) devido à diminuição da ingestão e da síntese na pele. A maioria das ações biológicas da VitD é mediada pelo receptor da vitamina D (VDR), que está presente nos neurônios e células gliais do hipocampo, e no córtex e em núcleos subcorticais, áreas essenciais para a cognição. Sabe-se que polimorfismos do gene VDR podem diminuir a afinidade do VDR pela VitD. Objetivo: O presente estudo teve como objetivo investigar a influência dos níveis de VitD no declínio cognitivo em pacientes com demência devida à doença de Alzheimer (DA, n = 32) e comprometimento cognitivo leve (CCL, n = 15) em comparação a um grupo de idosos cognitivamente saudáveis (n = 24). Nós também avaliamos a associação entre polimorfimos no gene do receptor de VitD e as alterações cognitivas. Métodos: Quatro polimorfismos no gene VDR foram estudados, sendo BsmI, ApaI, FokI e TaqI, por PCR-RFLP. Os níveis séricos de 25-hidroxi vitamina D (25(OH)D) foram determinados por HPLC. Resultados: Não houve diferença significativa nos níveis de 25(OH)D ou nas frequências genotípicas / alélicas entre os grupos. Níveis deficientes de 25(OH)D foram mais frequentes nas mulheres. Os genótipos AA / AG do polimorfismo BsmI foram associados a níveis suficientes de 25(OH)D, enquanto o genótipo GG deste mesmo polimorfismo foi associado a níveis insuficientes no grupo com comprometimento cognitivo (em indivíduos com DA ou CCL). Conclusões: Os resultados obtidos não confirmam a relação entre redução dos níveis de VitD, polimorfismos no gene VDR e função cognitiva alterada nesta amostra. No entanto, os dados indicam que o polimorfismo BsmI no gene VDR está associado aos níveis de VitD em indivíduos com declínio cognitivo.
ABSTRACT Elderly people are at a high risk of developing vitamin D (VitD) deficiency due to both decreased intake and cutaneous synthesis. Most of the biological actions of VitD are mediated by the vitamin D receptor (VDR), which is present in neurons and glial cells of the hippocampus, and in the cortex and subcortical nuclei, essential areas for cognition. It is known that VDR gene polymorphisms may decrease the VDR affinity for VitD. Objective: The present study aimed to investigate the influence of VitD levels on cognitive decline in patients with dementia due to Alzheimer's disease (AD, n = 32) and mild cognitive impairment (MCI, n = 15) compared to cognitively healthy elderly (n = 24). We also evaluated the association of VDR gene polymorphisms with cognitive disturbance. Methods: Four polymorphisms on the VDR gene were studied, namely, BsmI, ApaI, FokI and TaqI, by polymerase chain reaction-restriction fragment length polymorphism. Serum levels of 25-hydroxy vitamin D (25(OH)D) were determined by high performance liquid chromatography. Results: No significant difference in 25(OH)D levels or genotypic/allelic frequencies was observed between the groups. Deficiency of 25(OH)D was more frequently observed in women. The AA/AG genotypes of the BsmI polymorphism was associated with sufficient 25(OH)D levels, while the GG genotype of this same polymorphism was associated to insufficient levels in the cognitively-impaired group (individuals with AD or MCI). Conclusions: The data obtained do not confirm the relationship between reductions of VitD levels, polymorphisms in the VDR gene, and altered cognitive function in this sample. However, the data indicate that BsmI polymorphism in the VDR gene is associated with the VitD levels in individuals with cognitive decline.
https://doi.org/10.1590/0004-282x20180116
1884 downloads
10.
Cerebrospinal fluid biomarkers for the differential diagnosis of Alzheimer’s disease
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Magalhães, Carolina A.
; Figueiró, Micheli
; Fraga, Vanessa G.
; Mateo, Elvis C.
; Toledo, André A. S. F.
; Carvalho, Maria das Graças
; Caramelli, Paulo
; Gomes, Karina B.
.
Jornal Brasileiro de Patologia e Medicina Laboratorial
- Métricas do periódico
RESUMO Introdução: Estudos têm sido conduzidos no sentido de validar biomarcadores no liquor para o diagnóstico da doença de Alzheimer (DA), objetivando, sobretudo, facilitar o diagnóstico precoce. Objetivo: Avaliar os biomarcadores do liquor em indivíduos com provável DA, bem como a aplicabilidade dos valores de referência internacionais nesta população. Métodos: Foram recrutados 46 indivíduos, sendo classificados como provável DA (n = 19), comprometimento cognitivo leve (CCL) (n = 5) e outras demências (n = 22). Os biomarcadores foram dosados no liquor utilizando-se os kits INNOTEST por ensaio imunossorvente ligado à enzima (ELISA). Maiores valores de proteína Tau e menores valores de Aβ e índice Innotest Amiloide Tau Index (IATI) foram observados no grupo de DA quando comparados com o de CCL; maiores níveis de Tau e Tau fosforilada (Tau-P) e menores valores de Aβ e IATI foram observados no grupo de DA quando comparados com os pacientes que apresentavam outras demências. Nenhum biomarcador ou o IATI foi capaz de discernir entre CCL e outras demências. O índice kappa entre os biomarcadores e o diagnóstico clínico foi regular para a Tau e IATI, e fraco para Aβ e Tau-P. Conclusão: Os valores de cut-off para cada biomarcador que apresentou melhor sensibilidade e especificidade conjugadas diferiram dos valores de referência sugeridos pelo fabricante. Os biomarcadores do liquor representam importantes recursos que podem auxiliar no diagnóstico da DA, mas a interpretação dos resultados deve ser feita com base na análise dos três analitos em conjunto. Os valores de cut-off devem ser estabelecidos de modo a atender as especificidades e as características de cada população.
ABSTRACT Introduction: Several studies have been conducted in order to validate cerebrospinal fluid biomarkers for the diagnosis of Alzheimer’s disease (AD), aiming primarily to facilitate the early diagnosis. Objective: To evaluate CSF biomarkers on patients with probable AD and the applicability of the international references values in this population. Methods: 46 individuals were recruited and classified as probable AD (n = 19), mild cognitive impairment (MCI) (n = 5) and other dementias (n = 22). The cerebrospinal fluid (CSF) biomarkers were measured using the INNOTEST kits for enzyme-linked immunosorbent assay (ELISA). Higher Tau protein values and lower Aβand Innotest Amyloid Tau Index (IATI) values were observed in AD group when compared with MCI; higher levels of Tau and phosphorylated Tau (P-Tau), and lower Aβand IATI values were observed in AD group when compared to patients with other dementias. No biomarker or IATI was able to distinguish between MCI and other dementias. The kappa index between biomarkers and the clinical diagnosis was regular to Tau and IATI, and weak to Aβand P-tau. Conclusion: The cut-off values for each biomarker that showed better combined sensibility and specificity differ from the reference values suggested by the manufacturer. The CSF biomarkers represent important resources that can help with the AD diagnosis, although the results interpretation must be made based on the analysis of the three analytes together. The cut-off values must be established to address the specificities and characteristics of each population.
https://doi.org/10.5935/1676-2444.20150059
2997 downloads
11.
[RETRACTED ARTICLE] Derivation of new Brazilian lineages of human embryonic stem cells under physiological oxygen conditions
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Georges, J. A. O.
; Vergani, N.
; Fraga, A. M.
; Fonseca, S. A. S.
; Fujihara, L. S.
; Albuquerque, M. C. R. M.
; Castro, F. J. G.
; Silva, I. S.
; Pereira, L. V.
.
https://doi.org/10.1590/1519-6984.20813
1374 downloads
12.
Growing knowledge: an overview of Seed Plant diversity in Brazil
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Zappi, Daniela C.
; Filardi, Fabiana L. Ranzato
; Leitman, Paula
; Souza, Vinícius C.
; Walter, Bruno M.T.
; Pirani, José R.
; Morim, Marli P.
; Queiroz, Luciano P.
; Cavalcanti, Taciana B.
; Mansano, Vidal F.
; Forzza, Rafaela C.
; Abreu, Maria C.
; Acevedo-Rodríguez, Pedro
; Agra, Maria F.
; Almeida Jr., Eduardo B.
; Almeida, Gracineide S.S.
; Almeida, Rafael F.
; Alves, Flávio M.
; Alves, Marccus
; Alves-Araujo, Anderson
; Amaral, Maria C.E.
; Amorim, André M.
; Amorim, Bruno
; Andrade, Ivanilza M.
; Andreata, Regina H.P.
; Andrino, Caroline O.
; Anunciação, Elisete A.
; Aona, Lidyanne Y.S.
; Aranguren, Yani
; Aranha Filho, João L.M.
; Araújo, Andrea O.
; Araújo, Ariclenes A.M.
; Araújo, Diogo
; Arbo, María M.
; Assis, Leandro
; Assis, Marta C.
; Assunção, Vivian A.
; Athiê-Souza, Sarah M.
; Azevedo, Cecilia O.
; Baitello, João B.
; Barberena, Felipe F.V.A.
; Barbosa, Maria R.V.
; Barros, Fábio
; Barros, Lucas A.V.
; Barros, Michel J.F.
; Baumgratz, José F.A.
; Bernacci, Luis C.
; Berry, Paul E.
; Bigio, Narcísio C.
; Biral, Leonardo
; Bittrich, Volker
; Borges, Rafael A.X.
; Bortoluzzi, Roseli L.C.
; Bove, Cláudia P.
; Bovini, Massimo G.
; Braga, João M.A.
; Braz, Denise M.
; Bringel Jr., João B.A.
; Bruniera, Carla P.
; Buturi, Camila V.
; Cabral, Elza
; Cabral, Fernanda N.
; Caddah, Mayara K.
; Caires, Claudenir S.
; Calazans, Luana S.B.
; Calió, Maria F.
; Camargo, Rodrigo A.
; Campbell, Lisa
; Canto-Dorow, Thais S.
; Carauta, Jorge P.P.
; Cardiel, José M.
; Cardoso, Domingos B.O.S.
; Cardoso, Leandro J.T.
; Carneiro, Camila R.
; Carneiro, Cláudia E.
; Carneiro-Torres, Daniela S.
; Carrijo, Tatiana T.
; Caruzo, Maria B.R.
; Carvalho, Maria L.S.
; Carvalho-Silva, Micheline
; Castello, Ana C.D.
; Cavalheiro, Larissa
; Cervi, Armando C.
; Chacon, Roberta G.
; Chautems, Alain
; Chiavegatto, Berenice
; Chukr, Nádia S.
; Coelho, Alexa A.O.P.
; Coelho, Marcus A.N.
; Coelho, Rubens L.G.
; Cordeiro, Inês
; Cordula, Elizabeth
; Cornejo, Xavier
; Côrtes, Ana L.A.
; Costa, Andrea F.
; Costa, Fabiane N.
; Costa, Jorge A.S.
; Costa, Leila C.
; Costa-e-Silva, Maria B.
; Costa-Lima, James L.
; Cota, Maria R.C.
; Couto, Ricardo S.
; Daly, Douglas C.
; De Stefano, Rodrigo D.
; De Toni, Karen
; Dematteis, Massimiliano
; Dettke, Greta A.
; Di Maio, Fernando R.
; Dórea, Marcos C.
; Duarte, Marília C.
; Dutilh, Julie H.A.
; Dutra, Valquíria F.
; Echternacht, Lívia
; Eggers, Lilian
; Esteves, Gerleni
; Ezcurra, Cecilia
; Falcão Junior, Marcus J.A.
; Feres, Fabíola
; Fernandes, José M.
; Ferreira, D.M.C.
; Ferreira, Fabrício M.
; Ferreira, Gabriel E.
; Ferreira, Priscila P.A.
; Ferreira, Silvana C.
; Ferrucci, Maria S.
; Fiaschi, Pedro
; Filgueiras, Tarciso S.
; Firens, Marcela
; Flores, Andreia S.
; Forero, Enrique
; Forster, Wellington
; Fortuna-Perez, Ana P.
; Fortunato, Reneé H.
; Fraga, Cléudio N.
; França, Flávio
; Francener, Augusto
; Freitas, Joelcio
; Freitas, Maria F.
; Fritsch, Peter W.
; Furtado, Samyra G.
; Gaglioti, André L.
; Garcia, Flávia C.P.
; Germano Filho, Pedro
; Giacomin, Leandro
; Gil, André S.B.
; Giulietti, Ana M.
; A.P.Godoy, Silvana
; Goldenberg, Renato
; Gomes da Costa, Géssica A.
; Gomes, Mário
; Gomes-Klein, Vera L.
; Gonçalves, Eduardo Gomes
; Graham, Shirley
; Groppo, Milton
; Guedes, Juliana S.
; Guimarães, Leonardo R.S.
; Guimarães, Paulo J.F.
; Guimarães, Elsie F.
; Gutierrez, Raul
; Harley, Raymond
; Hassemer, Gustavo
; Hattori, Eric K.O.
; Hefler, Sonia M.
; Heiden, Gustavo
; Henderson, Andrew
; Hensold, Nancy
; Hiepko, Paul
; Holanda, Ana S.S.
; Iganci, João R.V.
; Imig, Daniela C.
; Indriunas, Alexandre
; Jacques, Eliane L.
; Jardim, Jomar G.
; Kamer, Hiltje M.
; Kameyama, Cíntia
; Kinoshita, Luiza S.
; Kirizawa, Mizué
; Klitgaard, Bente B.
; Koch, Ingrid
; Koschnitzke, Cristiana
; Krauss, Nathália P.
; Kriebel, Ricardo
; Kuntz, Juliana
; Larocca, João
; Leal, Eduardo S.
; Lewis, Gwilym P.
; Lima, Carla T.
; Lima, Haroldo C.
; Lima, Itamar B.
; Lima, Laíce F.G.
; Lima, Laura C.P.
; Lima, Leticia R.
; Lima, Luís F.P.
; Lima, Rita B.
; Lírio, Elton J.
; Liro, Renata M.
; Lleras, Eduardo
; Lobão, Adriana
; Loeuille, Benoit
; Lohmann, Lúcia G.
; Loiola, Maria I.B.
; Lombardi, Julio A.
; Longhi-Wagner, Hilda M.
; Lopes, Rosana C.
; Lorencini, Tiago S.
; Louzada, Rafael B.
; Lovo, Juliana
; Lozano, Eduardo D.
; Lucas, Eve
; Ludtke, Raquel
; Luz, Christian L.
; Maas, Paul
; Machado, Anderson F.P.
; Macias, Leila
; Maciel, Jefferson R.
; Magenta, Mara A.G.
; Mamede, Maria C.H.
; Manoel, Evelin A.
; Marchioretto, Maria S.
; Marques, Juliana S.
; Marquete, Nilda
; Marquete, Ronaldo
; Martinelli, Gustavo
; Martins da Silva, Regina C.V.
; Martins, Ângela B.
; Martins, Erika R.
; Martins, Márcio L.L.
; Martins, Milena V.
; Martins, Renata C.
; Matias, Ligia Q.
; Maya-L., Carlos A.
; Mayo, Simon
; Mazine, Fiorella
; Medeiros, Debora
; Medeiros, Erika S.
; Medeiros, Herison
; Medeiros, João D.
; Meireles, José E.
; Mello-Silva, Renato
; Melo, Aline
; Melo, André L.
; Melo, Efigênia
; Melo, José I.M.
; Menezes, Cristine G.
; Menini Neto, Luiz
; Mentz, Lilian A.
; Mezzonato, A.C.
; Michelangeli, Fabián A.
; Milward-de-Azevedo, Michaele A.
; Miotto, Silvia T.S.
; Miranda, Vitor F.O.
; Mondin, Cláudio A.
; Monge, Marcelo
; Monteiro, Daniele
; Monteiro, Raquel F.
; Moraes, Marta D.
; Moraes, Pedro L.R.
; Mori, Scott A.
; Mota, Aline C.
; Mota, Nara F.O.
; Moura, Tania M.
; Mulgura, Maria
; Nakajima, Jimi N.
; Nardy, Camila
; Nascimento Júnior, José E.
; Noblick, Larry
; Nunes, Teonildes S.
; O'Leary, Nataly
; Oliveira, Arline S.
; Oliveira, Caetano T.
; Oliveira, Juliana A.
; Oliveira, Luciana S.D.
; Oliveira, Maria L.A.A.
; Oliveira, Regina C.
; Oliveira, Renata S.
; Oliveira, Reyjane P.
; Paixão-Souza, Bruno
; Parra, Lara R.
; Pasini, Eduardo
; Pastore, José F.B.
; Pastore, Mayara
; Paula-Souza, Juliana
; Pederneiras, Leandro C.
; Peixoto, Ariane L.
; Pelissari, Gisela
; Pellegrini, Marco O.O.
; Pennington, Toby
; Perdiz, Ricardo O.
; Pereira, Anna C.M.
; Pereira, Maria S.
; Pereira, Rodrigo A.S.
; Pessoa, Clenia
; Pessoa, Edlley M.
; Pessoa, Maria C.R.
; Pinto, Luiz J.S.
; Pinto, Rafael B.
; Pontes, Tiago A.
; Prance, Ghillean T.
; Proença, Carolyn
; Profice, Sheila R.
; Pscheidt, Allan C.
; Queiroz, George A.
; Queiroz, Rubens T.
; Quinet, Alexandre
; Rainer, Heimo
; Ramos, Eliana
; Rando, Juliana G.
; Rapini, Alessandro
; Reginato, Marcelo
; Reis, Ilka P.
; Reis, Priscila A.
; Ribeiro, André R.O.
; Ribeiro, José E.L.S.
; Riina, Ricarda
; Ritter, Mara R.
; Rivadavia, Fernando
; Rocha, Antônio E.S.
; Rocha, Maria J.R.
; Rodrigues, Izabella M.C.
; Rodrigues, Karina F.
; Rodrigues, Rodrigo S.
; Rodrigues, Rodrigo S.
; Rodrigues, Vinícius T.
; Rodrigues, William
; Romaniuc Neto, Sérgio
; Romão, Gerson O.
; Romero, Rosana
; Roque, Nádia
; Rosa, Patrícia
; Rossi, Lúcia
; Sá, Cyl F.C.
; Saavedra, Mariana M.
; Saka, Mariana
; Sakuragui, Cássia M.
; Salas, Roberto M.
; Sales, Margareth F.
; Salimena, Fatima R.G.
; Sampaio, Daniela
; Sancho, Gisela
; Sano, Paulo T.
; Santos, Alessandra
; Santos, Élide P.
; Santos, Juliana S.
; Santos, Marianna R.
; Santos-Gonçalves, Ana P.
; Santos-Silva, Fernanda
; São-Mateus, Wallace
; Saraiva, Deisy P.
; Saridakis, Dennis P.
; Sartori, Ângela L.B.
; Scalon, Viviane R.
; Schneider, Ângelo
; Sebastiani, Renata
; Secco, Ricardo S.
; Senna, Luisa
; Senna-Valle, Luci
; Shirasuna, Regina T.
; Silva Filho, Pedro J.S.
; Silva, Anádria S.
; Silva, Christian
; Silva, Genilson A.R.
; Silva, Gisele O.
; Silva, Márcia C.R.
; Silva, Marcos J.
; Silva, Marcos J.
; Silva, Otávio L.M.
; Silva, Rafaela A.P.
; Silva, Saura R.
; Silva, Tania R.S.
; Silva-Gonçalves, Kelly C.
; Silva-Luz, Cíntia L.
; Simão-Bianchini, Rosângela
; Simões, André O.
; Simpson, Beryl
; Siniscalchi, Carolina M.
; Siqueira Filho, José A.
; Siqueira, Carlos E.
; Siqueira, Josafá C.
; Smith, Nathan P.
; Snak, Cristiane
; Soares Neto, Raimundo L.
; Soares, Kelen P.
; Soares, Marcos V.B.
; Soares, Maria L.
; Soares, Polyana N.
; Sobral, Marcos
; Sodré, Rodolfo C.
; Somner, Genise V.
; Sothers, Cynthia A.
; Sousa, Danilo J.L.
; Souza, Elnatan B.
; Souza, Élvia R.
; Souza, Marcelo
; Souza, Maria L.D.R.
; Souza-Buturi, Fátima O.
; Spina, Andréa P.
; Stapf, María N.S.
; Stefano, Marina V.
; Stehmann, João R.
; Steinmann, Victor
; Takeuchi, Cátia
; Taylor, Charlotte M.
; Taylor, Nigel P.
; Teles, Aristônio M.
; Temponi, Lívia G.
; Terra-Araujo, Mário H.
; Thode, Veronica
; Thomas, W.Wayt
; Tissot-Squalli, Mara L.
; Torke, Benjamin M.
; Torres, Roseli B.
; Tozzi, Ana M.G.A.
; Trad, Rafaela J.
; Trevisan, Rafael
; Trovó, Marcelo
; Valls, José F.M.
; Vaz, Angela M.S.F.
; Versieux, Leonardo
; Viana, Pedro L.
; Vianna Filho, Marcelo D.M.
; Vieira, Ana O.S.
; Vieira, Diego D.
; Vignoli-Silva, Márcia
; Vilar, Thaisa
; Vinhos, Franklin
; Wallnöfer, Bruno
; Wanderley, Maria G.L.
; Wasshausen, Dieter
; Watanabe, Maurício T.C.
; Weigend, Maximilian
; Welker, Cassiano A.D.
; Woodgyer, Elizabeth
; Xifreda, Cecilia C.
; Yamamoto, Kikyo
; Zanin, Ana
; Zenni, Rafael D.
; Zickel, Carmem S
.
Resumo Um levantamento atualizado das plantas com sementes e análises relevantes acerca desta biodiversidade são apresentados. Este trabalho se iniciou em 2010 com a publicação do Catálogo de Plantas e Fungos e, desde então vem sendo atualizado por mais de 430 especialistas trabalhando online. O Brasil abriga atualmente 32.086 espécies nativas de Angiospermas e 23 espécies nativas de Gimnospermas e estes novos dados mostram um aumento de 3% da riqueza em relação a 2010. A Amazônia é o Domínio Fitogeográfico com o maior número de espécies de Gimnospermas, enquanto que a Floresta Atlântica possui a maior riqueza de Angiospermas. Houve um crescimento considerável no número de espécies e nas taxas de endemismo para a maioria dos Domínios (Caatinga, Cerrado, Floresta Atlântica, Pampa e Pantanal), com exceção da Amazônia que apresentou uma diminuição de 2,5% de endemicidade. Entretanto, a maior parte das plantas com sementes que ocorrem no Brasil (57,4%) é endêmica deste território. A proporção de formas de vida varia de acordo com os diferentes Domínios: árvores são mais expressivas na Amazônia e Floresta Atlântica do que nos outros biomas, ervas são dominantes no Pampa e as lianas apresentam riqueza expressiva na Amazônia, Floresta Atlântica e Pantanal. Este trabalho não só quantifica a biodiversidade brasileira, mas também indica as lacunas de conhecimento e o desafio a ser enfrentado para a conservação desta flora.
Abstract An updated inventory of Brazilian seed plants is presented and offers important insights into the country's biodiversity. This work started in 2010, with the publication of the Plants and Fungi Catalogue, and has been updated since by more than 430 specialists working online. Brazil is home to 32,086 native Angiosperms and 23 native Gymnosperms, showing an increase of 3% in its species richness in relation to 2010. The Amazon Rainforest is the richest Brazilian biome for Gymnosperms, while the Atlantic Rainforest is the richest one for Angiosperms. There was a considerable increment in the number of species and endemism rates for biomes, except for the Amazon that showed a decrease of 2.5% of recorded endemics. However, well over half of Brazillian seed plant species (57.4%) is endemic to this territory. The proportion of life-forms varies among different biomes: trees are more expressive in the Amazon and Atlantic Rainforest biomes while herbs predominate in the Pampa, and lianas are more expressive in the Amazon, Atlantic Rainforest, and Pantanal. This compilation serves not only to quantify Brazilian biodiversity, but also to highlight areas where there information is lacking and to provide a framework for the challenge faced in conserving Brazil's unique and diverse flora.
https://doi.org/10.1590/2175-7860201566411
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13.
Molecular docking and molecular dynamic studies of semi-synthetic piperidine alkaloids as acetylcholinesterase inhibitors
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Danuello, Amanda
; Romeiro, Nelilma C.
; Giesel, Guilherme M.
; Pivatto, Marcos
; Viegas Jr., Claudio
; Verli, Hugo
; Barreiro, Eliezer J.
; Fraga, Carlos A. M.
; Castro, Newton G.
; Bolzani, Vanderlan S.
.
Journal of the Brazilian Chemical Society
- Métricas do periódico
A mistura dos derivados semissintéticos cloridrato da (-)-3-O-acetil-cassina e cloridrato da (-)-3-O-acetil-espectalina, preparada a partir da mistura dos alcalóides (-)-cassina e (-)-espectalina (4:1) obtida de Senna spectabilis, é um potente inibidor da acetilcolinesterase (AChE), assim justificando mais estudos moleculares. Neste sentido, estudos de docking e dinâmica moleculares foram conduzidos neste trabalho com o objetivo de adquirir uma compreensão mais profunda de todos os aspectos estruturais das moléculas cloridratos da (-)-3-O-acetil-cassina e (-)-3-O-acetil-espectalina, as quais diferem em seus potenciais inibidores de AChE. Os dois derivados em estudo apresentaram diversas interações com o sítio periférico aniônico dentro da cavidade catalítica de AChE de Torpedo californica. Entretanto, somente o composto majoritário (-)-3-O-acetil-cassina mostrou interação com a tríade catalítica de maneira significativa. As simulações de dinâmica molecular utilizando água como solvente foram importantes para compreender as interações hipotéticas entre cloridratos da (-)-3-O-acetil-cassina e (-)-3-O-acetil-espectalina com AChE. Os dados obtidos indicam que o composto (-)-3-O-acetil-cassina é o inibidor da enzima mais potente possivelmente devido às suas interações favoráveis com a proteína, com menor custo de dessolvatação. Estes resultados sugerem que o tamanho da cadeia lateral influencia no potencial inibitório das moléculas avaliadas e podem representar o ponto de partida para o desenvolvimento de novos derivados de (-)-3-O-acetil-cassina, objetivando a descoberta de inibidores de AChE mais eficazes.
The mixture of semi-synthetic derivatives (-)-3-O-acetyl-cassine hydrochloride and (-)-3-O-acetyl-spectaline hydrochloride, prepared from the mixture of natural alkaloids (-)-cassine and (-)-spectaline (4:1) isolated from Senna spectabilis, has been shown to be a potent acetylcholinesterase (AChE) inhibitor, thereby prompting further molecular studies. In this sense, docking and dynamic molecular studies were carried out in this work, aiming to acquire a deeper understanding about all the structural aspects of molecules (-)-3-O-acetyl-cassine and (-)-3-O-acetyl-spectaline hydrochlorides, which differ with respect to their AChE inhibitory potentials. Both molecules establish important interactions with the peripheral anionic site within the catalytic gorge of Torpedo californica AChE. However, only the major compound (-)-3-O-acetyl-cassine hydrochloride significantly interacts with the catalytic triad. Explicit-solvent molecular dynamic simulations were conducted in order to gain better understanding about the hypothetical interactions taking place between the semi-synthetic alkaloid molecules (-)-3-O-acetyl-cassine and (-)-3-O-acetyl-spectaline hydrochlorides and AChE. The data obtained in this study indicated that (-)-3-O-acetyl-cassine hydrochloride is the most potent inhibitor of AChE possibly due to the favorable interactions of this molecule with the target protein, with lower desolvation cost. These results suggested that the size of the side chain has an effect on the inhibitory potential of the evaluated molecules and may represent the starting point for the development of new derivatives of (-)-3-O-acetyl-cassine hydrochloride, with a view to the discovery of new effective AChE inhibitors.
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14.
Consumo hídrico e coeficiente de cultura da mamoneira na microrregião de Lavras, Minas Gerais
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Rios, Gervásio F. A.
; Carvalho, Luiz G. de
; Magina, Flávio de C.
; Castro Neto, Pedro
; Silva, Bruno M.
; Fraga, Antônio C.
.
Revista Brasileira de Engenharia Agrícola e Ambiental
- Métricas do periódico
Realizou-se este trabalho visando avaliar a evapotranspiração da cultura (ETc) e o coeficiente de cultivo (Kc) da cultura da mamoneira irrigada por gotejamento, sob as condições climáticas de Lavras, Minas Gerais, Brasil, no período de 24/01 a 30/08/2008. A ETc foi determinada por meio do balanço de energia, de acordo com o método da razão de Bowen, e o Kc pelos métodos e recomendações do boletim FAO 56, no período de 14/02 a 03/06/2008, correspondendo às fases I (crescimento), II (vegetativa) e III (frutificação) e para a fase IV (maturação) o Kc foi estimado por estar além do período de 03/06/2008; para isto, um experimento foi instalado no centro da área cultivada com sensores de temperatura e umidade relativa do ar, em dois níveis no dossel da cultura; de saldo de radiação (Rn) sobre o dossel da cultura e sensor de fluxo de calor no solo (G) a 0,08 m da superfície do solo. Os valores médios da ETc nas fases I, II e III, foram de 2,48, 2,68 e 3,04 mm d-1, respectivamente. O Kc assumiu, nessas respectivas fases, valores de 0,27, 0,46 e 0,87 e 0,57 na fase de maturação, situando-se dentro dos limites e recomendações do boletim FAO-56.
The study was carried out in order to evaluate the evapotranspiration (ETc) and crop coefficient (Kc) of castor bean by drip irrigation system, under the climatic conditions of Lavras, Minas Gerais State, Brazil, from 01/24 to 08/30/2008. The ETc was determined by the energy balance according to the Bowen ratio method and Kc by the methods and recommendations of the FAO-56 paper, from 02/14 to 06/03/2008, corresponding to phases I (growth), II (vegetative), III (fruiting) and IV (maturity). For this purpose, in the center of the experimental area, the sensors were installed to measure the temperature and relative humidity, at two levels above the crop canopy; the net radiation (Rn) and the soil heat flux (G) at 0.08 m under the soil surface. The average ETc values in phases I, II and III were 2.48, 2.68 and 3.04 mm d-1, respectively. The respective Kc in these phases were 0.27, 0.46, 0.87 and 0.57 in maturity phase, within the limits and recommendations of the FAO-56 paper.
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15.
A tool for errors detection in printed circuit boards production
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Journal of applied research and technology
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The progressive implementation of software functions in Integrated Circuits (ICs) has considerably increased the number of transistors and pin connections of ICs. For that reason, Printed Circuit Boards (PCBs) are fabricated with the Surface Mount Technology (SMT) nowadays and IC mounting on PCB is a crucial process that requires high precision. An Automatic Mechanical Montage (AMM) system is used to mount ICs on the sockets using a couple of reference points for every IC in order to find the correct positions for mounting the IC. Due to some factors in the process of PCB development, there are differences between designed and manufactured PCBs, which could generate delays in their production. In this work, a software tool which allows to work with digital images of PCBs is described. This tool finds the differences generated in PCB development, especially the differences in IC reference points using Digital Image Processing (DIP) techniques.
La realización progresiva de funciones de software en los Circuitos Integrados (CI) ha incrementado considerablemente el número de transistores así como de pines de conexión de los CI. Por esta razón, hoy en día las Tarjetas de Circuito Impreso (TCI) son fabricadas con la Tecnología de Montaje Superficial y el montaje de los CI sobre la TCI es un proceso crucial que requiere una alta precisión. Un sistema de Montaje Mecánico Automático (MMA) se usa para montar los CI sobre los zócalos usando unos puntos de referencia para cada CI de modo que encuentra los posiciones correctas para el montaje del CI. Dados algunos factores en el proceso de desarrollos de las TCI, existen diferencias entre las TCI diseñadas y las manufacturadas, las cuales generan retardos en su producción. En este trabajo se describe una herramienta de software que permite trabajar con imágenes digitales de una TCI. Esta herramienta encuentra las diferencias generadas en el desarrollo de TCI, especialmente las diferencias en los puntos de referencia para CI usando técnicas de Procesamiento Digital de Imágenes.
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