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1.
Soft Matter ; 20(9): 2151-2161, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38351846

RESUMO

The interaction between passive and active/driven particles has introduced a new way to control colloidal suspension properties from particle aggregation to crystallization. Here, we focus on the hydrodynamic interaction between a single rotational driven particle and a suspension of passive particles near the floor. Using experiments and Stokesian dynamics simulations that account for near-field lubrication, we demonstrate that the flow induced by the driven particle can induce long-ranged rearrangement in a passive suspension. We observe an accumulation of passive particles in front of the driven particle and a depletion of passive particles behind the driven particle. This restructuring generates a pattern that can span a range more than 10 times the driven particles radius. We further show that size scale of the pattern is only a function of the particles height above the floor.

2.
ISA Trans ; 144: 319-329, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37977884

RESUMO

This manuscript deals with the trajectory-tracking problem for linear time-invariant systems with parameter uncertainties and time-dependent external perturbations. A robust finite-time model reference adaptive controller is proposed. In the absence of external perturbations, the proposed controller ensures finite-time convergence to zero of the tracking and parameter identification errors. In presence of time-dependent external perturbations, the tracking and parameter identification errors converge to a region around the origin in a finite time. The convergence proofs are developed based on Lyapunov and input-to-state stability theory. Finally, simulation results in an academic example and a flexible-joint robot manipulator show the feasibility of the proposed approach.

3.
J Vasc Access ; : 11297298231202634, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37817674

RESUMO

BACKGROUND: The criteria for vascular access (VA) selection in pediatric hemodialysis (HD) population has changed over time until the current patient-centered approach using the individualized Life-Plan. We analyzed the type of VA used by incident and prevalent end-stage kidney disease (ESKD) pediatric patients (pts) treated with HD in Catalonia. METHOD: Data from the Catalan Renal Registry of ESKD pts under 18 years of age undergoing kidney replacement therapy (KRT) were examined for a 22-year period (1997-2018). RESULTS: ESKD children starting KRT through HD decreased progressively from 55.6% (1997-2001) to 38.2% (2012-2018) and, conversely, there was an increase in pts starting KRT by preemptive kidney transplantation (KT) from 28.9% to 42.6% between the same periods (for both comparisons, p = 0.007). Most ESKD pts started HD by fistula (AVF) from 1997 to 2001 (56.5%) but this percentage decreased over time and no AVFs were used to start HD in children from 2012 to 2018. Likewise, the percentage of children starting HD by tunneled catheter increased progressively from 8.7% to 72.2% between the same periods (for both comparisons, p < 0.001). Regarding prevalent ESKD pts, children on HD decreased from 34.9% in 1997 to 4.7% in 2018 and, conversely, pts with a functioning kidney graft increased from 62.8% to 92.4% during the same periods (for both comparisons, p < 0.001). There was a progressive decrease in the percentage of children dialyzed by AVF from 100% in 1997 to 0% in 2018 (p < 0.001). The KT rate increased from 5.4 per million population (pmp) in 1997 to 17.1 pmp in 2018 (p = 0.007). The median time on HD prior to the first KT progressively decreased to 6.6 months (2014-2018). CONCLUSION: The high KT rate was a determining factor in choosing the VA type in the incident and prevalent pediatric population treated with HD in Catalonia.

4.
Nature ; 617(7961): 467-468, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37198306
5.
Front Endocrinol (Lausanne) ; 13: 795225, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528003

RESUMO

In diabetes mellitus (DM) treatment, Continuous Glucose Monitoring (CGM) linked with insulin delivery becomes the main strategy to improve therapeutic outcomes and quality of patients' lives. However, Blood Glucose (BG) regulation with CGM is still hampered by limitations of algorithms and glucose sensors. Regarding sensor technology, current electrochemical glucose sensors do not capture the full spectrum of other physiological signals, i.e., lipids, amino acids or hormones, relaying the general body status. Regarding algorithms, variability between and within patients remains the main challenge for optimal BG regulation in closed-loop therapies. This work highlights the simulation benefits to test new sensing and control paradigms which address the previous shortcomings for Type 1 Diabetes (T1D) closed-loop therapies. The UVA/Padova T1DM Simulator is the core element here, which is a computer model of the human metabolic system based on glucose-insulin dynamics in T1D patients. That simulator is approved by the US Food and Drug Administration (FDA) as an alternative for pre-clinical testing of new devices and closed-loop algorithms. To overcome the limitation of standard glucose sensors, the concept of an islet-based biosensor, which could integrate multiple physiological signals through electrical activity measurement, is assessed here in a closed-loop insulin therapy. This investigation has been addressed by an interdisciplinary consortium, from endocrinology to biology, electrophysiology, bio-electronics and control theory. In parallel to the development of an islet-based closed-loop, it also investigates the benefits of robust control theory against the natural variability within a patient population. Using 4 meal scenarios, numerous simulation campaigns were conducted. The analysis of their results then introduces a discussion on the potential benefits of an Artificial Pancreas (AP) system associating the islet-based biosensor with robust algorithms.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus Tipo 1 , Glicemia/análise , Automonitorização da Glicemia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Insulina , Sistemas de Infusão de Insulina , Estados Unidos
6.
Angle Orthod ; 92(3): 347-352, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35421894

RESUMO

OBJECTIVES: To evaluate root resorption of lower incisors and canines quantitatively in a group of patients who underwent orthodontic treatment with piezocision and/or a collagen reinforcement technique with a fully resorbable three-dimensional (3D) collagen xenograft matrix compared with a control group. MATERIALS AND METHODS: The study sample of this secondary analysis consisted of 32 periodontally healthy patients with angle Class I malocclusion or mild Class II or III malocclusion and moderate irregularity index scores who underwent orthodontic treatment and had before (T0) and after treatment (T1) cone-beam computed tomography scans. Root resorption of lower incisors and canines was assessed quantitatively in the following four groups: the control group received orthodontic treatment without piezocision, experimental group 1 received orthodontic treatment with piezocision, experimental group 2 received orthodontic treatment with piezocision and a 3D collagen matrix, and experimental group 3 received orthodontic treatment with a 3D collagen matrix. RESULTS: An overall statistically significant decrease in root length from T0 to T1 for all groups was observed (P < .05). However, there was no significant difference among the groups in the amount of root length decrease from T0 to T1. CONCLUSIONS: Orthodontic treatment combined with piezocision does not increase the risk of root resorption of lower incisors and canines when compared with orthodontic treatment without acceleration techniques. More studies with larger samples should be undertaken to confirm these results.


Assuntos
Má Oclusão Classe I de Angle , Reabsorção da Raiz , Tomografia Computadorizada de Feixe Cônico , Humanos , Incisivo/diagnóstico por imagem , Incisivo/cirurgia , Má Oclusão Classe I de Angle/etiologia , Reabsorção da Raiz/diagnóstico por imagem , Reabsorção da Raiz/etiologia , Técnicas de Movimentação Dentária/efeitos adversos
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2948-2951, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891863

RESUMO

In this paper, machine learning approaches are proposed to support dental researchers and clinicians to study the shape and position of dental crowns and roots, by implementing a Patient Specific Classification and Prediction tool that includes RootCanalSeg and DentalModelSeg algorithms and then merges the output of these tools for intraoral scanning and volumetric dental imaging. RootCanalSeg combines image processing and machine learning approaches to automatically segment the root canals of the lower and upper jaws from large datasets, providing clinical information on tooth long axis for orthodontics, endodontics, prosthodontic and restorative dentistry procedures. DentalModelSeg includes segmenting the teeth from the crown shape to provide clinical information on each individual tooth. The merging algorithm then allows users to integrate dental models for quantitative assessments. Precision in dentistry has been mainly driven by dental crown surface characteristics, but information on tooth root morphology and position is important for successful root canal preparation, pulp regeneration, planning of orthodontic movement, restorative and implant dentistry. In this paper we propose a patient specific classification and prediction of dental root canal and crown shape analysis workflow that employs image processing and machine learning methods to analyze crown surfaces, obtained by intraoral scanners, and three-dimensional volumetric images of the jaws and teeth root canals, obtained by cone beam computed tomography (CBCT).


Assuntos
Cavidade Pulpar , Polpa Dentária , Tomografia Computadorizada de Feixe Cônico , Coroas , Cavidade Pulpar/diagnóstico por imagem , Humanos , Regeneração
8.
Bol. malariol. salud ambient ; 61(4): 536-547, dic. 2021. tab.
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1392365

RESUMO

En condiciones adecuadas como humedad, alcalinidad, o temperatura, determinados patógenos logran adherirse a las superficies y sobrevivir ciertos períodos fuera de un anfitrión, persistiendo en algunos casos a procesos deficientes de limpieza y desinfección, configurándose como un posible foco de transmisión. Por ello, el correcto saneamiento cumple un propósito vital en la protección de los trabajadores de la industria y otros sectores frente al riesgo de contaminación por contacto directo con las superficies contaminadas. La literatura científica muestra amplia evidencia de la supervivencia de patógenos sobre superficies que son habituales dentro de instalaciones industriales, como acero, aluminio, madera, plástico y vidrio. La supervivencia de microorganismos en las superficies puede configurarse como candidato a marcador de biodisponibilidad, que puede ser usado en la industria para establecer y auditar los planes de higienización y saneamiento industrial, permitiendo estudiar la eficacia de los compuestos usados en la desinfección, y variables como su concentración, temperatura, e intervalos de aplicación y remoción(AU)


Under suitable conditions such as humidity, alkalinity, or temperature, certain pathogens manage to adhere to surfaces and survive certain periods outside of a host, persisting in some cases to poor cleaning and disinfection processes, becoming a possible source of transmission. Therefore, proper sanitation serves a vital purpose in protecting workers in industry and other sectors from the risk of contamination by direct contact with contaminated surfaces. The scientific literature shows ample evidence of the survival of pathogens on surfaces that are common within industrial facilities, such as steel, aluminum, wood, plastic and glass. The survival of microorganisms on surfaces can be configured as a candidate for bioavailability marker, which can be used in the industry to establish and audit industrial sanitation and sanitation plans, allowing to study the efficacy of the compounds used in disinfection, and variables such as its concentration, temperature, and application and removal intervals(AU(


Assuntos
Disponibilidade Biológica , Desinfecção , Saneamento na Indústria , Poluição Ambiental , Noxas , Plásticos , Aço , Madeira , Alumínio , Instalações Industriais e de Manufatura , Vidro
9.
Bol. malariol. salud ambient ; 61(4): 657-663, dic. 2021. tab., ilus.
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1396110

RESUMO

Se ha comprobado que la exposición a bioaerosoles se asocia con varios efectos sobre la salud, como enfermedades pulmonares y alergias. El presente estudio transversal tuvo como objetivo investigar la contaminación por hongos en varias superficies pertenecientes a dos industrias de alimentos. La toma de muestra se realizó en tres semanas, inmediatamente después de realizada la limpieza y desinfección y antes de iniciar la producción. Se recolectaron 400 muestras de superficie (vidrio, acero inoxidable, aluminio, goma y plástico), también se evaluó la eficacia del programa de higienización en el control de la población de hongos. Todas las muestras presentaron recuentos fúngicos <10 ufc/cm2, sin haber diferencias significativas entre los tipos de superficie, sin embargo, las superficies plásticas exhibieron mayor crecimiento logarítmico de los hongos. Se determinó que 49,60% de las especies identificadas correspondieron al género Penicillium. Aunque los niveles de hongos en las industrias estudiadas fueron inferiores a los niveles recomendados por la Organización Mundial de la Salud, algunas medidas de salud ambiental como lavar y desinfectar las superficies después de cada turno de trabajo, y se recomiendan inspecciones periódicas para garantizar la seguridad de los trabajadores y de los productos que allí se manufacturan(AU)


It has been proven that exposure to bioaerosols is associated with several health effects, such as pulmonary diseases and allergies. The present crosssectional study aimed to investigate fungal contamination on various surfaces belonging to two food industries. The sampling was carried out in three weeks, immediately after cleaning and disinfection and before starting production. 400 surface samples were collected (glass, stainless steel, aluminum, rubber and plastic), the effectiveness of the sanitation program in controlling the fungal population was also evaluated. All the samples presented fungal counts <10 cfu / cm2, with no significant differences between the types of surfaces, however, the plastic surfaces exhibited higher logarithmic growth of the fungi. It was determined that 49.60% of the identified species corresponded to the Penicillium genus.Although the levels of fungi in the studied baths were lower than the levels recommended by the World Health Organization, some environmental health measure ssuch as washing and disinfecting surfaces after each working shift and periodic inspections are recommended ensuring the safety of the workers and the products that are manufactured there(AU)


Assuntos
Humanos , Contagem de Colônia Microbiana , Indústria Alimentícia , Saneamento/métodos , Poluição Ambiental/prevenção & controle , Fungos , Penicillium , Plásticos , Aspergillus , Rhizopus , Aço Inoxidável , Riscos Ocupacionais , Desinfecção/métodos , Alternaria , Alimentos , Instalações Industriais e de Manufatura , Vidro , Categorias de Trabalhadores
10.
Bol. malariol. salud ambient ; 61(4): 683-692, dic. 2021. tab., ilus.
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1397253

RESUMO

La lucha epidemiológica contra la pandemia COVID-19 ha incluido medidas sociales como el confinamiento y el cierre de actividades laborales y académicas. A consecuencia, tareas que se llevaban a cabo en el contexto presencial debieron ser ejecutadas desde los hogares, adoptando estrategias como el teletrabajo y la educación virtual, haciendo necesario el uso de herramientas como ordenadores y laptops. De allí que las personas han incrementado la exposición a las pantallas de dispositivos electrónicos, como son computadoras y laptops, trayendo como consecuencia afectaciones en la salud visual de las personas tales como el síndrome visual informático (SVI). Se realizó un estudio transversal con el objetivo de determinar la afectación por SVI en la población peruana y su relación con la exposición prolongada a DEV, generada a raíz de las medidas sociales de enfrentamiento a la pandemia de COVID-19. El tiempo promedio en que los sujetos de nuestro estudio usaron DEV dentro de los hogares se acrecentó un 120%, es decir 4,26±2,36 horas diarias adicionales al comparar con el año anterior a la pandemia COVID-19. La adopción masiva de actividades como el teletrabajo y la educación virtual podrían explicar el hecho que los grupos de empleados/patronos y estudiantes fueron los mayores usuarios de DEV, con 10,41 y 9,32 horas diarias. De acuerdo a los hallazgos obtenidos, es estadísticamente válido afirmar que las medidas sociales para enfrentar la pandemia COVID-19 indujeron al aumento en la prevalencia de SVI en los pobladores peruanos (p<0,001). En la actual investigación, la proporción de individuos que manifestaron SVI pasó de 38 a 64%, antes y durante la aplicación de las medidas, respectivamente(AU)


The epidemiological fight against the COVID-19 pandemic has included social measures such as confinement and the closure of work and academic activities. As a consequence, tasks that were carried out in the face-to-face context had to be carried out from homes, adopting strategies such as teleworking and virtual education, requiring the use of tools such as computers and laptops. Hence, people have increased exposure to the screens of electronic devices, such as computers and laptops, resulting in effects on people's visual health such as computer vision syndrome (SVI). A cross-sectional study was carried out in order to determine the affectation by SVI in the Peruvian population and its relationship with prolonged exposure to DEV, generated as a result of social measures to cope with the COVID-19 pandemic. The average time in which the subjects in our study used DEV within homes increased by 120%, that is, 4.26 ± 2.36 additional daily hours when compared to the year before the COVID-19 pandemic. The massive adoption of activities such as teleworking and virtual education could explain the fact that groups of employees / employers and students were the largest users of DEV, with 10.41 and 9.32 hours per day. According to the findings obtained, it is statistically valid to affirm that the social measures to face the COVID-19 pandemic induced an increase in the prevalence of SVI in the Peruvian population (p <0.001). In the current investigation, the proportion of individuals who manifested SVI went from 38 to 64%, before and during the application of the measures, respectively(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Disparidade Visual , Astenopia , Educação a Distância , Teletrabalho , COVID-19/prevenção & controle , Peru , Síndrome , Computadores , Saúde Ocular , Estudos Transversais , Estratégias de Saúde , Miopia
11.
Bol. malariol. salud ambient ; 61(3): 401-408, ago. 2021. tab.
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1400105

RESUMO

El objetivo de este artículo es analizar la literatura existente sobre el SVI y sus afectaciones a las personas producto por alta exposición a equipos electrónicos generados por la pandemia del COVID-19 El tipo de investigación es revisión de literatura, de diseño bibliográfico o documental; el método de investigación empleado fue el de revisión de literatura. La población estuvo constituida por 35 artículos y la muestra de 19 artículos en diversos idiomas, seleccionados de manera intencional de acuerdo a criterios de inclusión y exclusión previamente establecidos; las técnicas e instrumentos empleados para el recojo de información fueron el análisis documental, y el fichaje y la computadora respectivamente. Entre los principales resultados se tiene que el SVI tiene gran prevalencia en personas que tienen gran periodo de exposición a pantallas de dispositivos electrónicos, asimismo, vinculados a fallas en las condiciones ergonómicas en sus estaciones de trabajo o estudio. Se concluye, el promedio de prevalencia del SVI en los artículos revisados es de 73.2%, siendo el máximo 98.7% y el mínimo 50%, siendo más frecuente en mujeres; respecto a los síntomas más frecuente que se presentan se tienen: dolor en ojos, cansancio visual o visión borrosa, picazón, sequedad en los ojos, sensación de empeoramiento de la vista, lagrimeo y párpados pesados(AU)


The objective of this article is to analyze the existing literature on IVS and its effects on people as a result of high exposure to electronic equipment generated by the COVID-19 pandemic. The type of research is literature review, bibliographic or documentary design; the research method used was the literature review. The population consisted of 35 articles and the sample of 19 articles in various languages, intentionally selected according to previously established inclusion and exclusion criteria; the techniques and instruments used for the collection of information were the documentary analysis, and the signing and the computer respectively. Among the main results is that SVI has a high prevalence in people who have a long period of exposure to electronic device screens, also linked to failures in ergonomic conditions in their workstations or study. It is concluded that the average prevalence of SVI in the reviewed articles is 73.2%, the maximum being 98.7% and the minimum 50%, being more frequent in women; Regarding the most frequent symptoms that appear, there are: pain in the eyes, visual fatigue or blurred vision, itching, dry eyes, sensation of worsening of sight, tearing and heavy eyelids(AU)


Assuntos
Humanos , Masculino , Feminino , Literatura de Revisão como Assunto , Síndromes do Olho Seco/etiologia , Astenopia , Oftalmopatias/etiologia , Tempo de Tela , Prevalência , Fatores de Risco , COVID-19 , Ergonomia
12.
Bol. malariol. salud ambient ; 61(3): 486-495, ago. 2021. tab., ilus.
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1418332

RESUMO

El COVID persistente se caracteriza por síntomas y secuelas funcionales y psicológicas que persisten por más de 12 semanas post infección, tales como: fatiga, disnea, ansiedad, depresión; generando inconvenientes en la reanudación de actividades laborales de los trabajadores. Se realizó un estudio epidemiológico descriptivo de corte transversal, evaluando la reincorporación de trabajadores operadores de industrias metalmecánicas de Lima, Perú; recuperados y COVID persistentes, entre el tercer trimestre 2020 y primer trimestre 2021. Se aplicaron las escalas de disnea de Borg y la escala de disnea modificada del Medical Research Council (mMRC), además de la escala de ansiedad y depresión de Goldberg. Los resultados se analizaron mediante estadística descriptiva, empleando medidas de tendencia central y dispersión. Se observó que más del 80% de trabajadores recuperados son reincorporados; y para COVID persistente se reincorpora entre 75% y 43% para los cargos 8121 y 8122, respectivamente. El esfuerzo respiratorio en reposo resultó normal por la escala de Borg para cada grupo, mientras que en esfuerzo se obtuvo un valor R2= 0.2986 indicando la no reincorporación en 74,51% y 43,33% en las categorias 8121 y 8122, respectivamente; además 45,12% y 42,68% de los trabajadores recuperados y COVID persistentes mostraron sintomas de fatiga; 36,25% y 35,26% de ansiedad; 25,4% y 15,21% de depresión, respectivamente; asimismo, el total de trabajadores presentaron sobrepeso con IMC promedio > 26 Kg/m2; siendo más elevado en mujeres (27,4 Kg/m2). El COVID-19 afecta la salud de trabajadores (recuperados y COVID persistentes), reduce el reintegro al trabajo y en consecuencia la productividad de las empresas(AU)


Persistent COVID is characterized by functional and psychological symptoms and sequelae that persist for more than 12 weeks post infection, such as: fatigue, dyspnea, anxiety, depression; generating inconveniences in the resumption of work activities of workers. A descriptive, cross-sectional epidemiological study was carried out, evaluating the reincorporation of workers operating in metalworking industries in Lima, Peru; recovered and persistent COVID, between the third quarter 2020 and the first quarter 2021. The Borg dyspnea scales and the modified dyspnea scale of the Medical Research Council (mMRC) were applied, in addition to the Goldberg anxiety and depression scale. The results were analyzed using descriptive statistics, using measures of central tendency and dispersion. It was observed that more than 80% of recovered workers are reinstated; and for persistent COVID, between 75% and 43% are reinstated for charges 8121 and 8122, respectively. Respiratory effort at rest was normal by the Borg scale for each group, while in effort a value R2 = 0.2986 was obtained, indicating no reincorporation in 74.51% and 43.33% in categories 8121 and 8122, respectively; also 45.12% and 42.68% of the recovered workers and persistent COVID showed symptoms of fatigue; 36.25% and 35.26% anxiety; 25.4% and 15.21% of depression, respectively; Likewise, the total of workers were overweight with an average BMI> 26 Kg / m2; being higher in women (27.4 Kg / m2). COVID-19 affects the health of workers (recovered and persistent COVID), reduces return to work and consequently the productivity of companies(AU)


Assuntos
Humanos , Masculino , Feminino , Dispneia , Retorno ao Trabalho , COVID-19/complicações , Síndrome de COVID-19 Pós-Aguda , Ansiedade , Peru/epidemiologia , Estudos Epidemiológicos , Indústria Metalúrgica , Pessoal de Operação , Estudos Transversais , Depressão , Sobrepeso , Categorias de Trabalhadores
13.
Bol. malariol. salud ambient ; 61(3): 527-532, ago. 2021. tab.
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1418408

RESUMO

Los trabajadores de la industria están expuestos a distintos tipos de riesgos, incluyendo la exposición laboral a agentes biológicos como virus, bacterias, hongos, parásitos, esporas o toxinas capaces de originar algún tipo de infección, enfermedad o toxicidad. Gran variedad de estos patógenos ha sido identificada sobre distintas superficies dentro de instalaciones de trabajo, persistiendo en algunos casos luego de las jornadas de limpieza habituales, e incluso sobreviviendo por largos períodos de tiempo. Los hallazgos preliminares indican que los procesos de higiene en dos industrias permitieron disminuir de manera estadísticamente significativa la presencia de E. Coli y Sars-Cov-2, en las superficies dentro de las instalaciones. Por el contrario, en una tercera industria se observó que los procesos de higiene y limpieza no lograron reducir eficazmente la presencia de los patógenos La auditoría de higiene en instalaciones de industrias textiles debe incluir la capacidad de hallar e identificar los peligros biológicos que aún estén presentes en superficies, una vez ejecutados los protocolos rutinarios de limpieza y desinfección establecidos por la organización. Para esta labor proponemos la práctica complementaria de tres procedimientos: la determinación microbiológica, mediante torundas o placas de contacto, la determinación visual con luz ultravioleta, para comprobar el grado de eficacia de la limpieza, y la determinación específica, consistente en la detección de ARN de virus SARS-CoV-2 (causante del COVID-19) en muestras ambientales de superficies por el método de PCR en tiempo real(AU)


Industrial workers are exposed to different types of risks, including occupational exposure to biological agents such as viruses, bacteria, fungi, parasites, spores or toxins capable of causing some type of infection, disease or toxicity. A great variety of these pathogens have been identified on different surfaces within work facilities, persisting in some cases after the usual cleaning days, and even surviving for long periods of time. Preliminary findings indicate that hygiene processes in two industries allowed a statistically significant decrease in the presence of E. Coli and Sars-Cov-2, on surfaces within the facilities. On the contrary, in a third industry it was observed that hygiene and cleaning processes failed to effectively reduce the presence of pathogens Hygiene audit in textile industry facilities should include the ability to find and identify biological hazards that are still present on surfaces, once the routine cleaning and disinfection protocols established by the organization have been executed. For this work, we propose the complementary practice of three procedures: microbiological determination, using swabs or contact plates, visual determination with ultraviolet light, to verify the degree of cleaning efficiency, and specific determination, consisting of RNA detection. of SARS-CoV-2 virus (causing COVID-19) in environmental samples of surfaces by the real-time PCR method(AU)


Assuntos
Humanos , Medidas de Segurança/organização & administração , Riscos Ocupacionais , Escherichia coli , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2 , COVID-19/prevenção & controle , Peru , Indústria Têxtil , Raios Ultravioleta , Desinfecção , Exposição Ocupacional
14.
Artigo em Inglês | MEDLINE | ID: mdl-33758460

RESUMO

In this paper, we present FlyBy CNN, a novel deep learning based approach for 3D shape segmentation. FlyByCNN consists of sampling the surface of the 3D object from different view points and extracting surface features such as the normal vectors. The generated 2D images are then analyzed via 2D convolutional neural networks such as RUNETs. We test our framework in a dental application for segmentation of intra-oral surfaces. The RUNET is trained for the segmentation task using image pairs of surface features and image labels as ground truth. The resulting labels from each segmented image are put back into the surface thanks to our sampling approach that generates 1-1 correspondence of image pixels and triangles in the surface model. The segmentation task achieved an accuracy of 0.9.

15.
Am J Orthod Dentofacial Orthop ; 159(3): e233-e243, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33487497

RESUMO

INTRODUCTION: This study aimed to compare the extent of buccal bone defects (dehiscences and fenestrations) and transversal tooth movement of mandibular lateral segments in patients after orthodontic treatment with and without piezocision in cone-beam computed tomography and digital dental models. METHODS: The study sample of this study consisted of cone-beam computed tomography scans and digital dental models taken before (T0) and after (T1) orthodontic treatment of 36 patients with moderate mandibular anterior crowding. The experimental group consisted of 17 patients that had piezocision performed at the beginning of treatment with the goal of accelerating tooth movement, which was compared with 19 patients who did not receive piezocision. The measurement of bone defects, buccolingual inclination, and transversal distances of the tooth in the mandibular lateral segments (mandibular canines, premolars, and first molars) were evaluated at baseline and at the end of the orthodontic treatment. RESULTS: Overall, an increase in dehiscences, buccal inclination, and arch width from T0 to T1 was observed in both groups, but no statistically significant difference was found between groups. A significant increase in fenestrations from T0 to T1 was observed only for the canines in the experimental group. No statistically significant association was found between the increase of dehiscences and the amount of buccolingual inclination or transversal width changes. However, the changes in transversal width were statistically significantly associated with the increase in buccal inclination at the canines, first and second premolars. CONCLUSIONS: No significant differences were found in buccal dehiscences and transversal tooth movement (buccolingual inclination and arch width) of mandibular lateral segments between patients after orthodontic treatment with and without piezocision. Dehiscences, buccal inclination, and arch width significantly increased from T0 to T1 in both groups.


Assuntos
Mandíbula , Técnicas de Movimentação Dentária , Estudos de Casos e Controles , Tomografia Computadorizada de Feixe Cônico , Dente Canino/diagnóstico por imagem , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Estudos Retrospectivos
16.
Colomb Med (Cali) ; 51(1): e4141, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32952230

RESUMO

AIM: We aimed to evaluate the correlation between the polymorphism of the interleukin 1-Beta (IL1-ß, +3954 C>T) and tooth movement, in a group of Colombian patients undergoing surgically accelerated orthodontic tooth movement. METHODS: The study was nested to a controlled clinical trial. Blood samples were taken from 11 women and 29 healthy Colombian male volunteers between 18 and 40 years old, after 1 year of starting orthodontic treatment. The patients presented malocclusion class I, with grade II or III. To detect the genetic polymorphism of the nucleotide +3954 C to T in the IL-1ß gene, we used a real-time PCR assay. RESULTS: Eleven individuals presented the allele 2 (T) heterozygous with the allele 1 (T/C) and 19 individuals were homozygous for the allele 1 (C/C). When analyzing the presence of the SNP, no significant differences were found in any of the variables. The best treatment was reflected in Group 3 (selective upper and lower alveolar decortication and 3D collagen matrix) and Group 4 (only selective alveolar decortication in the upper arch, with 3D collagen matrix), with 27% and 35% more speed respectively than in the control group. CONCLUSIONS: Our analyses indicated that a reduction in the total treatment time can be mostly potentiated by using decortication and collagen matrices and not for the presence of the allele 2 in the IL-1ß. Nevertheless, it is important that further studies investigate if the polymorphism could be associated with the speed of tooth movement and analyze the baseline protein levels.


OBJETIVO: Evaluar la correlación entre el polimorfismo de la interleucina 1-Beta (IL1-ß, +3954 C> T) y el movimiento de los dientes, en un grupo de pacientes colombianos sometidos a un movimiento dental ortodóncico acelerado quirúrgicamente. MÉTODOS: Este fue un estudio secundario derivado de un ensayo clínico aleatorio controlado. Se tomaron muestras de sangre de 11 mujeres y 29 voluntarios varones colombianos sanos entre 18 y 40 años, después de 1 año de comenzar el tratamiento de ortodoncia. Los pacientes presentaron maloclusión clase I, con grado II o III. Para detectar el polimorfismo genético del nucleótido +3954 C a T en el gen IL-1ß, se usó un ensayo de PCR en tiempo real. RESULTADOS: 11 individuos presentaron el alelo 2 (T) heterocigoto con el alelo 1 (T / C) y 19 individuos fueron homocigotos para el alelo 1 (C / C). Al analizar la presencia del SNP, no se encontraron diferencias significativas en ninguna de las variables. El mejor tratamiento se reflejó en el Grupo 3 (decorticación alveolar superior e inferior selectiva y matriz de colágeno 3D) y el Grupo 4 (solo decorticación alveolar selectiva en el arco superior, con matriz de colágeno 3D), con un 27% y un 35% más de velocidad, respectivamente, que en el grupo de control. CONCLUSIONES: Los análisis indicaron que una reducción en el tiempo total de tratamiento puede potenciarse principalmente mediante el uso de decorticación y matrices de colágeno y no por la presencia del alelo 2 en la IL-1ß. Sin embargo, es importante que otros estudios investiguen si el polimorfismo podría estar asociado con la velocidad del movimiento de los dientes y analizar los niveles de proteína de referencia.


Assuntos
Interleucina-1beta/genética , Má Oclusão/genética , Má Oclusão/terapia , Polimorfismo de Nucleotídeo Único , Técnicas de Movimentação Dentária/métodos , Adulto , Alelos , Colômbia , Análise de Dados , Feminino , Heterozigoto , Homozigoto , Humanos , Estimativa de Kaplan-Meier , Masculino , Má Oclusão/classificação , Mecanotransdução Celular/fisiologia , Duração da Cirurgia , Fatores de Tempo , Adulto Jovem
17.
Colomb. med ; 51(1): e4141, Jan.-Mar. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1124606

RESUMO

Abstract Aim: We aimed to evaluate the correlation between the polymorphism of the interleukin 1-Beta (IL1-β, +3954 C>T) and tooth movement, in a group of Colombian patients undergoing surgically accelerated orthodontic tooth movement. Methods: The study was nested to a controlled clinical trial. Blood samples were taken from 11 women and 29 healthy Colombian male volunteers between 18 and 40 years old, after 1 year of starting orthodontic treatment. The patients presented malocclusion class I, with grade II or III. To detect the genetic polymorphism of the nucleotide +3954 C to T in the IL-1β gene, we used a real-time PCR assay. Results: Eleven individuals presented the allele 2 (T) heterozygous with the allele 1 (T/C) and 19 individuals were homozygous for the allele 1 (C/C). When analyzing the presence of the SNP, no significant differences were found in any of the variables. The best treatment was reflected in Group 3 (selective upper and lower alveolar decortication and 3D collagen matrix) and Group 4 (only selective alveolar decortication in the upper arch, with 3D collagen matrix), with 27% and 35% more speed respectively than in the control group. Conclusions: Our analyses indicated that a reduction in the total treatment time can be mostly potentiated by using decortication and collagen matrices and not for the presence of the allele 2 in the IL-1β. Nevertheless, it is important that further studies investigate if the polymorphism could be associated with the speed of tooth movement and analyze the baseline protein levels.


Resumen Objetivo: Evaluar la correlación entre el polimorfismo de la interleucina 1-Beta (IL1-β, +3954 C> T) y el movimiento de los dientes, en un grupo de pacientes colombianos sometidos a un movimiento dental ortodóncico acelerado quirúrgicamente. Métodos: Este fue un estudio secundario derivado de un ensayo clínico aleatorio controlado. Se tomaron muestras de sangre de 11 mujeres y 29 voluntarios varones colombianos sanos entre 18 y 40 años, después de 1 año de comenzar el tratamiento de ortodoncia. Los pacientes presentaron maloclusión clase I, con grado II o III. Para detectar el polimorfismo genético del nucleótido +3954 C a T en el gen IL-1β, se usó un ensayo de PCR en tiempo real. Resultados: 11 individuos presentaron el alelo 2 (T) heterocigoto con el alelo 1 (T / C) y 19 individuos fueron homocigotos para el alelo 1 (C / C). Al analizar la presencia del SNP, no se encontraron diferencias significativas en ninguna de las variables. El mejor tratamiento se reflejó en el Grupo 3 (decorticación alveolar superior e inferior selectiva y matriz de colágeno 3D) y el Grupo 4 (solo decorticación alveolar selectiva en el arco superior, con matriz de colágeno 3D), con un 27% y un 35% más de velocidad, respectivamente, que en el grupo de control. Conclusiones: Los análisis indicaron que una reducción en el tiempo total de tratamiento puede potenciarse principalmente mediante el uso de decorticación y matrices de colágeno y no por la presencia del alelo 2 en la IL-1β. Sin embargo, es importante que otros estudios investiguen si el polimorfismo podría estar asociado con la velocidad del movimiento de los dientes y analizar los niveles de proteína de referencia.


Assuntos
Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Técnicas de Movimentação Dentária/métodos , Polimorfismo de Nucleotídeo Único , Interleucina-1beta/genética , Má Oclusão/genética , Má Oclusão/terapia , Fatores de Tempo , Colômbia , Mecanotransdução Celular/fisiologia , Alelos , Estimativa de Kaplan-Meier , Duração da Cirurgia , Análise de Dados , Heterozigoto , Homozigoto , Má Oclusão/classificação
18.
Shape Med Imaging (2020) ; 12474: 145-153, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33385170

RESUMO

This paper proposes machine learning approaches to support dentistry researchers in the context of integrating imaging modalities to analyze the morphology of tooth crowns and roots. One of the challenges to jointly analyze crowns and roots with precision is that two different image modalities are needed. Precision in dentistry is mainly driven by dental crown surfaces characteristics, but information on tooth root shape and position is of great value for successful root canal preparation, pulp regeneration, planning of orthodontic movement, restorative and implant dentistry. An innovative approach is to use image processing and machine learning to combine crown surfaces, obtained by intraoral scanners, with three dimensional volumetric images of the jaws and teeth root canals, obtained by cone beam computed tomography. In this paper, we propose a patient specific classification of dental root canal and crown shape analysis workflow that is widely applicable.

19.
Orthod Craniofac Res ; 23(1): 118-128, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31628885

RESUMO

OBJECTIVE: To compare the three-dimensional (3D) linear displacements and the mesiodistal and buccolingual angulation changes after orthodontic treatment in digital dental models (DDMs) and 3D models derived from cone-beam computed tomography (CBCT). SETTINGS AND SAMPLE POPULATION: Digital dental model and CBCT scans were selected from 24 adults who had undergone orthodontic treatment for mandibular anterior crowding. MATERIAL AND METHODS: 3D linear displacements and changes in angular measurements (mesiodistal and buccolingual angulation) were assessed in pre- and post-treatment DDM and CBCT images using the software ITK-snap and 3D SlicerCMF. Intra- and inter-rater agreement of measurements in DDM and CBCT were tested using the intraclass correlation coefficient (ICC). DDM and CBCT measurements were compared using the Wilcoxon test (P < .05), ICC and Bland-Altman plots. RESULTS: Intra- and inter-rater agreement varied from good (ICC > 0.75) to excellent (ICC > 0.90) for both DDM and CBCT measurements. Although no significant difference between DDM and CBCT methods was observed for linear measurements of tooth movement, the angular assessments were different for most measurements. The agreement between measurements from both assessments varied from poor to excellent. CONCLUSIONS: Longitudinal assessments of tooth movements including 3D linear displacements and mesiodistal and buccolingual angulation are reproducible when using both DDM and CBCT. Changes in angular measurements due to orthodontic treatment are discordant when measured in the digital models (clinical crown) and in the CBCT images (whole tooth).


Assuntos
Má Oclusão , Dente , Adulto , Tomografia Computadorizada de Feixe Cônico , Humanos , Imageamento Tridimensional , Modelos Dentários , Reprodutibilidade dos Testes
20.
Rev. Fac. Odontol. Univ. Antioq ; 31(1): 147-161, July-Dec. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1115198

RESUMO

ABSTRACT Introduction: the aim of this systematic review is to explore the published literature to analyze the relationship between polymorphism of interleukin 1-beta (IL-1β) and orthodontics. Methods: the search strategy developed for Medline, Scopus and Embase was used, verifying search records and selecting articles according to the guidelines set forth by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Two researchers evaluated studies in humans undergoing orthodontic treatment that evaluate IL-1β polymorphism, movement speed and/or root resorption, including clinical trials, case-control studies, cross-sectional studies, and cohort studies, published up to April 2017. Results: of the 123 relevant articles identified, 9 studies published between 2001 and 2016 were included in the detailed analysis. Studies on tooth movement generally agree that there is an increase in IL-1β levels in the first hours after starting the orthodontic treatment. Conclusion: an association of IL-1β polymorphism with external root resorption and tooth movement speed was found.


RESUMEN Introducción: el objetivo de esta revisión sistemática es analizar, a través de la literatura publicada, la relación entre el polimorfismo de la interleuquina 1 beta (IL-1β) y la ortodoncia. Métodos: se aplicó la estrategia de búsqueda desarrollada para Medline, Scopus y Embase y se verificaron los registros de la búsqueda y los artículos seleccionados de acuerdo a los lineamientos de la declaración para Revisiones Sistemáticas y Metaanálisis (PRISMA). Dos investigadores evaluaron los estudios en humanos sometidos a tratamiento de ortodoncia, donde se evalúan el polimorfismo de la IL-1β y la velocidad de movimiento y/o resorción radicular, como ensayos clínicos, estudios de casos y controles, estudios transversales o estudios de cohortes, publicados hasta abril de 2017. Resultados: de los 123 estudios relevantes identificados, 9 de ellos, publicados entre 2001 y 2016, fueron incluidos en el análisis detallado. Los estudios de movimiento dental concuerdan en el aumento de los niveles de IL-1β en las primeras horas de inicio del tratamiento ortodóncico. Conclusión: se encontró asociación del polimorfismo de la IL-1β con la resorción radicular externa y la velocidad de movimiento dental.


Assuntos
Interleucina-1beta , Ortodontia , Reabsorção da Raiz , Técnicas de Movimentação Dentária
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