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1.
Int J Numer Method Biomed Eng ; 40(8): e3843, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38963037

RESUMO

Infrared thermography is gaining relevance in breast cancer assessment. For this purpose, breast segmentation in thermograms is an important task for performing automatic image analysis and detecting possible temperature changes that indicate the presence of malignancy. However, it is not a simple task since the breast limit borders, especially the top borders, often have low contrast, making it difficult to isolate the breast area. Several algorithms have been proposed for breast segmentation, but these highly depend on the contrast at the lower breast borders and on filtering algorithms to remove false edges. This work focuses on taking advantage of the distinctive inframammary shape to simplify the definition of the lower breast border, regardless of the contrast level, which indeed also provides a strong anatomical reference to support the definition of the poorly marked upper boundary of the breasts, which has been one of the major challenges in the literature. In order to demonstrate viability of the proposed technique for an automatic breast segmentation, we applied it to a database with 180 thermograms and compared their results with those reported by others in the literature. We found that our approach achieved a high performance, in terms of Intersection over Union of 0.934, even higher than that reported by artificial intelligence algorithms. The performance is invariant to breast sizes and thermal contrast of the images.


Assuntos
Algoritmos , Mama , Termografia , Humanos , Termografia/métodos , Feminino , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Raios Infravermelhos , Processamento de Imagem Assistida por Computador/métodos
2.
Nanotechnology ; 34(45)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37536304

RESUMO

In magnetic tunnel junctions based on iron oxide nanoparticles the disorder and the oxidation state of the surface spin as well as the nanoparticles functionalization play a crucial role in the magnetotransport properties. In this work, we report a systematic study of the effects of vacuum annealing on the structural, magnetic and transport properties of self-assembled ∼10 nm Fe3O4nanoparticles. The high temperature treatment (from 573 to 873 K) decomposes the organic coating into amorphous carbon, reducing the electrical resistivity of the assemblies by 4 orders of magnitude. At the same time, the 3.Fe2+/(Fe3++Fe2+) ratio is reduced from 1.11 to 0.13 when the annealing temperature of the sample increases from 573 to 873 K, indicating an important surface oxidation. Although the 2 nm physical gap remains unchanged with the thermal treatment, a monotonous decrease of tunnel barrier width was obtained from the electron transport measurements when the annealing temperature increases, indicating an increment in the number of defects and hot-spots in the gap between the nanoparticles. This is reflected in the reduction of the spin dependent tunneling, which reduces the interparticle magnetoresistance. This work shows new insights about influence of the nanoparticle interfacial composition, as well their the spatial arrangement, on the tunnel transport of self-assemblies, and evidence the importance of optimizing the nanostructure fabrication for increasing the tunneling current without degrading the spin polarized current.

3.
Rev. biol. trop ; 71abr. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1449491

RESUMO

Introducción: Enfrentar la acelerada degradación de arrecifes coralinos requiere una acción integrada en múltiples niveles sociales y ecológicos. A escala local se debe incluir la participación activa de los usuarios de los recursos. Objetivo: evaluar el conocimiento y percepción local sobre los arrecifes coralinos en Golfo Dulce, y así generar bases para la integración social en la restauración coralina. Métodos: se realizaron 183 entrevistas en siete comunidades costeras del Golfo Dulce entre septiembre del 2016 y marzo del 2017. Los entrevistados se clasificaron en: (1) Pesca artesanal (PA) = 57 entrevistados, (2) Turismo (T) = 62, y (3) Otros (O) = 64. La primera parte de la entrevista fue de conocimiento y se asignó una nota basada en respuestas correctas. Según la nota se clasificó como informado, información media o desinformado. La segunda parte se basó en escalas de percepción sobre: (I) visitación, (II) factores que dañan los arrecifes coralinos, (III) medidas de manejo y (IV) salud de recursos marinos en Golfo Dulce. Resultados: El grupo T tuvo el mayor porcentaje de entrevistados informados = 42 % y el grupo O de desinformados = 37 %. La segunda parte fue percepción, más del 50 % de PA y T consideran que la visita es frecuente. La sedimentación y contaminación por agroquímicos fueron identificados por más del 60 % de PA y T como la principal amenaza. El 35 % de PA y el 40 % de T perciben las boyas fijas como la mejor medida para el Golfo Dulce. La restricción de visitas fue la medida con menor aceptación. El 60 % de los entrevistados de PA y T consideran que los recursos marinos del golfo estarán peor que en la actualidad. Conclusiones: Estos resultados confirman la importancia de comprender el conocimiento y la percepción de los usuarios de los arrecifes de coral en los procesos participativos y educativos en la restauración y conservación de los arrecifes de coral.


Introduction: Addressing the accelerated coral reefs degradation requires integrated action at multiple social and ecological scales. At local level, active participation of the main users must be included. Objective: To evaluate local knowledge and perception about coral reefs in Golfo Dulce to generate bases for social integration in coral restoration. Methods: 183 interviews were conducted in coastal communities in Golfo Dulce, between September 2016 and March 2017. The interviewees were classified as: (1) Artisanal fishing (PA) = 57 interviewees, (2) Tourism (T) = 62, and (3) Others (O) = 64. The first part of the interview was about knowledge and a grade was assigned based on correct answers. According to the grade, they were classified as informed, medium information or uninformed. The second part was based on perception scales on: (I) visitation, (II) factors that damage coral reefs, (III) management measures, and (IV) health of marine resources in Golfo Dulce. Results: Group T had the highest percentage of informed interviewees = 42 % and group O uninformed = 37 %. The second part was perception, more than 50 % of PA and T consider that the visit is frequent. Sedimentation and contamination by agrochemicals were identified by more than 60 % of PA and T as the main threat. 35 % of PA and 40 % of T perceive permanent buoys as the best measure for the Golfo Dulce. The visitation restriction was the measure with the least acceptance. 60 % of the interviewees of PA and T consider that the marine resources of the gulf will be worse than today. Conclusions: These results confirm the importance of understading coral reefs users knowledge and perception in participatory and educational processes in coral reef restoration and conservation.

5.
Arch. pediatr. Urug ; 93(2): e805, dic. 2022.
Artigo em Espanhol | LILACS, UY-BNMED, BNUY | ID: biblio-1411600

RESUMO

Introducción: en muchas oportunidades el/la pediatra o médica/o de familia será la primera persona a la que consulten los niños/as y adolescentes trans a fin de plantear sus dudas y experiencias, por lo tanto es fundamental que el/la profesional aborde en la consulta esta temática sin prejuicios, con una mirada actualizada en el marco de los derechos de niñas, niños y adolescentes. Objetivo: brindar herramientas para un adecuado acompañamiento y seguimiento en la atención en salud a las infancias y adolescencias trans en el primer nivel de atención. Metodología: para la elaboración de esta guía se hizo una revisión bibliográfica en Pubmed y Scielo. Se realizó dicha búsqueda desde 2010 a la fecha con el prescriptor "infancias trans", "adolescencias trans", en inglés y en idioma español. Resultados: se elaboraron guías para el abordaje en la atención en el primer nivel de atención de niños/as y adolescentes trans aportando herramientas para la historia clínica, teniendo en cuenta la entrevista, el examen físico y el abordaje multi e interdisciplinario. Conclusiones: las experiencias trans en las infancias y adolescencias no deben ser miradas desde un enfoque patologizador sino como vivencias legítimas. El/la profesional de la salud juega un rol fundamental en la función de acompañamiento y como garante de sus derechos promoviendo la autonomía en la toma de decisiones.


Introduction: many times pediatricians or family doctors are the first people trans-children and adolescents consult and raise questions and experiences to. Therefore, it is key for doctors to have an unbiassed approach to this issue in the consultation, with an updated view of the framework of children and adolescents. Objective: provide tools for proper health care support and follow-up ifor trans children and adolescents at primary care. Methodology: for the preparation of these guidelines, we made a bibliographic review in Pubmed, Scielo. This search was carried out from 2010 to date using "trans children", "trans adolescents" prescribers, in English and in Spanish. Results: guidelines were created for primary care regarding the care of trans children and adolescents, providing tools for medical records and considering the interview, the physical examination and the multi-interdisciplinary approach. Conclusions: trans experiences in childhood and adolescence should not be viewed from a pathologizing perspective, but rather as legitimate experiences. Health professionals play a key role in accompanying and guarding the rights of children and adolescents and promoting their autonomy in decision-making instances.


Introdução: em muitas ocasiões, o pediatra ou médico de família é a primeira pessoa que as crianças e adolescentes trans consultam para compartilhar suas dúvidas e vivências, por isso é fundamental que ele aborde a consulta sobre esse assunto sem preconceitos, com uma perspectiva atualizada no marco dos direitos de crianças e adolescentes. Objetivo: fornecer ferramentas para suporte e acompanhamento adequados no atendimento da saúde de crianças e adolescentes trans no primeiro nível de atenção. Metodologia: para a elaboração deste guia, foi feita uma revisão bibliográfica no Pubmed, Scielo. A pesquisa com as palavras "crianças trans", "adolescentes trans", vem sendo realizada desde 2010 até hoje em inglês e espanhol. Resultados: foram elaboradas diretrizes para a abordagem do cuidado no primeiro nível de atenção a crianças e a adolescentes trans, fornecendo instrumentos para a história clínica, levando em consideração a entrevista, o exame físico e a abordagem multidisciplinar. Conclusões: as experiências trans na infância e adolescência não devem ser vistas a partir de uma abordagem patologizante, mas sim como experiências legítimas. O profissional de saúde tem papel fundamental na função de acompanhamento e como garantidor de seus direitos, promovendo autonomia na tomada de decisões.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Atenção Primária à Saúde/normas , Saúde da Criança , Saúde do Adolescente , Pessoas Transgênero , Serviços de Saúde para Pessoas Transgênero/normas
6.
Sci Rep ; 12(1): 10321, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725742

RESUMO

Tsunamis are natural phenomena that, although occasional, can have large impacts on coastal environments and settlements, especially in terms of loss of life. An accurate, detailed and timely assessment of the hazard is essential as input for mitigation strategies both in the long term and during emergencies. This goal is compounded by the high computational cost of simulating an adequate number of scenarios to make robust assessments. To reduce this handicap, alternative methods could be used. Here, an enhanced method for estimating tsunami time series using a one-dimensional convolutional neural network model (1D CNN) is considered. While the use of deep learning for this problem is not new, most of existing research has focused on assessing the capability of a network to reproduce inundation metrics extrema. However, for the context of Tsunami Early Warning, it is equally relevant to assess whether the networks can accurately predict whether inundation would occur or not, and its time series if it does. Hence, a set of 6776 scenarios with magnitudes in the range [Formula: see text] 8.0-9.2 were used to design several 1D CNN models at two bays that have different hydrodynamic behavior, that would use as input inexpensive low-resolution numerical modeling of tsunami propagation to predict inundation time series at pinpoint locations. In addition, different configuration parameters were also analyzed to outline a methodology for model testing and design, that could be applied elsewhere. The results show that the network models are capable of reproducing inundation time series well, either for small or large flow depths, but also when no inundation was forecast, with minimal instances of false alarms or missed alarms. To further assess the performance, the model was tested with two past tsunamis and compared with actual inundation metrics. The results obtained are promising, and the proposed model could become a reliable alternative for the calculation of tsunami intensity measures in a faster than real time manner. This could complement existing early warning system, by means of an approximate and fast procedure that could allow simulating a larger number of scenarios within the always restricting time frame of tsunami emergencies.


Assuntos
Emergências , Tsunamis , Meio Ambiente , Humanos , Redes Neurais de Computação
7.
J Appl Microbiol ; 132(5): 3650-3663, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35233885

RESUMO

AIMS: This study assessed, at the physiological and molecular levels, the effect of biogas on indole-3-acetic acid (IAA) biosynthesis by Azospirillum brasilense as well as the impact of this bacterium during CO2 fixation from biogas by Chlorella vulgaris and Scenedesmus obliquus. METHODS AND RESULTS: IpdC gene expression, IAA production and the growth of A. brasilense cultured under air (control) and biogas (treatment) were evaluated. The results demonstrated that A. brasilense had a better growth capacity and IAA production (105.7 ± 10.3 µg ml-1 ) when cultured under biogas composed of 25% CO2  + 75% methane (CH4 ) with respect to the control (72.4 ± 7.9 µg ml-1 ), although the ipdC gene expression level was low under the stressful condition generated by biogas. Moreover, this bacterium was able to induce a higher cell density and CO2 fixation rate from biogas by C. vulgaris (0.27 ± 0.08 g l-1 d-1 ) and S. obliquus (0.22 ± 0.08 g l-1 d-1 ). CONCLUSIONS: This study demonstrated that A. brasilense has the capacity to grow and actively maintain its main microalgal growth-promoting mechanism when cultured under biogas and positively influence CO2 fixation from the biogas of C. vulgaris and S. obliquus. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings broaden research in the field of Azospirillum-microalga interactions and the prevalence of Azospirillum in environmental and ecological topics in addition to supporting the uses of plant growth-promoting bacteria to enhance biotechnological strategies for biogas upgrading.


Assuntos
Azospirillum brasilense , Chlorella vulgaris , Microalgas , Atmosfera , Azospirillum brasilense/genética , Azospirillum brasilense/metabolismo , Biocombustíveis , Dióxido de Carbono/metabolismo , Chlorella vulgaris/metabolismo , Ácidos Indolacéticos/metabolismo , Microalgas/metabolismo
8.
Injury ; 51(12): 2834-2839, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33162012

RESUMO

INTRODUCTION: By May 2020, Peru was the country with the third most COVID-19 cases in the Americas. The current study's overall aim was to examine the impact of the current COVID-19 outbreak on the number of non-COVID-related patient presentations to a major national emergency traumatology/orthopedics referral center in Latin America. METHODS: An observational study was performed at one of Peru's main tertiary trauma referral centers, during the current COVID-19 pandemic. Numbers of non-follow-up patients presenting to the traumatology/ orthopedics service were counted and compared between January through April 2019 and January through April 2020; and between the month immediately prior to the Peruvian government's implementation of national lock-down measures (Feb 16-Mar 15; Period 1) and the month immediately following (Mar 16-Apr 15; Period 2). The number of surgery service hospitalizations also was compared pre- versus post lockdown initiation (Period 1 vs. 2), as were patient characteristics and outcomes, like age, sex, discharge disposition, mortality, indications for hospital admission, and COVID-19 status. RESULT: Comparing 2019 and 2020, no appreciable differences were detected in the number of patients seen in either January or February. However, relative to March and April 2019, the numbers of patients seen in March and April 2020 (the two months after the first Peruvian case of COVID-19 was detected) were reduced by 55.8 and 88.6%, respectively. Comparing the months immediately pre and post lockdown, the number of service patients declined by 79.9% in April, while the number of hospitalizations declined by 30.9%. The number of admissions for various surgical indications either remained stable or declined in parallel with the overall decline in admissions for all indications except for osteoporotic hip fractures and diabetic foot ulcers (both of which increased proportional to the overall number of admissions) and for hand and foot fractures, both of which decreased. CONCLUSION: At our hospital, not all indications for traumatology/orthopedics service utilization declined despite the national government's directive to reduce non-COVID-related consultations and admissions. Some disorders presented with even greater frequency, which must be considered when developing contingencies for the reallocation of healthcare resources during a pandemic.


Assuntos
COVID-19/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Centros de Atenção Terciária/estatística & dados numéricos , Centros de Traumatologia/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , COVID-19/prevenção & controle , COVID-19/virologia , Comorbidade , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Peru/epidemiologia , Encaminhamento e Consulta/estatística & dados numéricos , SARS-CoV-2/isolamento & purificação , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/terapia
9.
Rev. biol. trop ; 67(3)jun. 2019.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1507522

RESUMO

Rubus adenotrichos is an Andean blackberry plant bearing glandular trichomes which secrete an adhesive exudate. The resin bug Heniartes stali is frequently found on this plant and collects this exudate using the forelegs to enhance its preying capacity. Here, we describe the morphology of the plant's glandular trichomes with the aid of light and scanning electron microscopy, as well as the chemical components of the exudate by histochemical and gas chromatography-mass spectrometry analysis. We have also combined behavioral observations with the analysis of the insect leg morphology to identify possible morpho-functional adaptations evolved by H. stali for collecting the sticky secretions. Glandular trichomes exhibited a multicellular long stalk and a calyx-shaped head with radially aligned cells. The composition of the resinous fluid was mainly terpenes and phenolics, which may contribute to its sticky properties. Brush-like structures on the tibia of forelegs in H. stali suggests an adaptive trait for collecting the trichomes exudate. A profusely hair-covered area on metatibiae operated as a resin storage structure. Abundant pore-like openings were observed in the cuticle of this area through which substances could be conceivably secreted to prevent resin hardening. These findings combine morphological and chemical features of a fascinating insect-plant interaction in the Neotropics.


Rubus adenotrichos es una planta de mora andina que contiene tricomas glandulares los cuales secretan un exudado pegajoso. El chinche de las resinas Heniartes stali se encuentra con frecuencia en esta planta recogiendo el exudado con sus patas delanteras para mejorar su capacidad en la captura de las presas. En este trabajo empleamos microscopía de luz y microscopía electrónica de barrido para describir la morfología de los tricomas. Los constituyentes químicos del exudado fueron estudiados mediante técnicas histoquímicas, de cromatografía de gases y espectrometría de masas. También combinamos observaciones del comportamiento del insecto en la recolección y almacenamiento del exudado con el análisis de la morfología de sus patas, empleando microscopía de luz y microscopía electrónica de barrido para identificar las posibles adaptaciones morfo-funcionales desarrolladas para la manipulación de estas secreciones adhesivas. Los tricomas glandulares exhibieron un tallo largo multicelular y una cabeza glandular en forma de cáliz con células alineadas radialmente. El fluido resinoso estaba compuesto principalmente por terpenos y compuestos fenólicos, los cuales parecen contribuir con sus propiedades adhesivas. La presencia de estructuras tipo pincel en las puntas de las tibias de las patas delanteras sugieren un carácter adaptativo para recoger el exudado de los tricomas. También describimos un área en las patas traseras profusamente cubierta de pelos, que funcionaban como estructuras de almacenamiento de la resina. En la cutícula de éstas observamos abundantes aberturas similares a poros y sugerimos que a través de ellos se secretan sustancias que impiden el endurecimiento de la resina almacenada. Estos hallazgos aportan información sobre características morfológicas y químicas de un novedoso modelo de interacción insecto-planta en el neotrópico.

10.
Exp Parasitol ; 198: 31-38, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30690024

RESUMO

Diverse spiro dihydroquinoline-oxindoles (JS series) were prepared using the BF3•OEt2-catalyzed imino Diels-Alder reaction between ketimine-isatin derivatives and trans-isoeugenol. Ten spiro-oxiindole derivatives were selected and evaluated at different stages of the life cycle of Leishmania braziliensis parasites, responsible for cutaneous leishmaniasis in South America. Among them, the 8'-ethyl-4'-(4-hydroxy-3-methoxyphenyl)-3'-methyl-3',4'-dihydro-1'H-spiro[indoline-3,2'-quinolin]-2-one called JS87 was able to inhibit the growth of promastigotes without affecting the mammalian cells viability, and to decrease the number of intracellular amastigotes of L. braziliensis. This spiro compound was found to act through the alteration of parasite internal regulation by disrupting the regulatory volume decrease (RVD), and to affect the sterol biosynthetic pathway at level of squalene epoxidase (SE) enzyme. These results revealed that the spiro annulation between quinoline and oxindole scaffolds enhances the anti-leishmanial activity, and could assist in the development of potent quinoline-oxindole hybrids against Leishmania braziliensis, the main etiological agent of cutaneous leishmaniasis in South America.


Assuntos
Antiprotozoários/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Oxindóis/farmacologia , Quinolinas/farmacologia , Compostos de Espiro/farmacologia , Animais , Antiprotozoários/química , Concentração Inibidora 50 , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/metabolismo , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Oxindóis/química , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/farmacologia , Quinolinas/química , Compostos de Espiro/química
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