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1.
PLoS One ; 19(4): e0300544, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656972

RESUMO

Obesity is a major global health epidemic that has adverse effects on both the people affected as well as the cost to society. Several anti-obesity drugs that target GLP-1 receptors have recently come to the market. Here, we describe the effects of tesofensine, a novel anti-obesity drug that acts as a triple monoamine neurotransmitter reuptake inhibitor. Using various techniques, we investigated its effects on weight loss and underlying neuronal mechanisms in mice and rats. These include behavioral tasks, DeepLabCut videotaped analysis, electrophysiological ensemble recordings, optogenetic activation, and chemogenetic silencing of GABAergic neurons in the Lateral Hypothalamus (LH). We found that tesofensine induces a greater weight loss in obese rats than lean rats, while differentially modulating the neuronal ensembles and population activity in LH. In Vgat-ChR2 and Vgat-IRES-cre transgenic mice, we found for the first time that tesofensine inhibited a subset of LH GABAergic neurons, reducing their ability to promote feeding behavior, and chemogenetically silencing them enhanced tesofensine's food-suppressing effects. Unlike phentermine, a dopaminergic appetite suppressant, tesofensine causes few, if any, head-weaving stereotypy at therapeutic doses. Most importantly, we found that tesofensine prolonged the weight loss induced by 5-HTP, a serotonin precursor, and blocked the body weight rebound that often occurs after weight loss. Behavioral studies on rats with the tastant sucrose indicated that tesofensine's appetite suppressant effects are independent of taste aversion and do not directly affect the perception of sweetness or palatability of sucrose. In summary, our data provide new insights into the effects of tesofensine on weight loss and the underlying neuronal mechanisms, suggesting that tesofensine may be an effective treatment for obesity and that it may be a valuable adjunct to other appetite suppressants to prevent body weight rebound.


Assuntos
Fármacos Antiobesidade , Compostos Bicíclicos Heterocíclicos com Pontes , Neurônios GABAérgicos , Obesidade , Animais , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/metabolismo , Ratos , Camundongos , Fármacos Antiobesidade/farmacologia , Masculino , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Comportamento Alimentar/efeitos dos fármacos , Região Hipotalâmica Lateral/efeitos dos fármacos , Região Hipotalâmica Lateral/metabolismo , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Camundongos Transgênicos , Redução de Peso/efeitos dos fármacos , Ratos Sprague-Dawley
2.
Arch Peru Cardiol Cir Cardiovasc ; 1(3): 188-193, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-38090201

RESUMO

Acute aortic syndromes (AAS) include a variety of overlapping anatomical and clinical conditions. Intramural hematoma (IMH), penetrating aortic ulcer, and aortic dissection occur in isolation or may coexist in the same patient. IMH represents 5-30% of all AAS and 60-70% of cases are located in the descending aorta. The diagnosis relies on a high index of clinical suspicion and on the use of complementary images. Management is conservative, but patients with some high-risk characteristics have a higher risk of mortality in the acute phase, so initial endovascular management should be considered. We present the case of a 69-year-old patient, in whom IMH was diagnosed in the course of a hypertensive emergency and who required hybrid management due to high-risk anatomical characteristics for endovascular management only.

3.
Nanomaterials (Basel) ; 13(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37513134

RESUMO

In this work, the SET and RESET processes of bipolar resistive switching memories with silicon nanocrystals (Si-NCs) embedded in an oxide matrix is simulated by a stochastic model. This model is based on the estimation of two-dimensional oxygen vacancy configurations and their relationship with the resistive state. The simulation data are compared with the experimental current-voltage data of Si-NCs/SiO2 multilayer-based memristor devices. Devices with 1 and 3 Si-NCs/SiO2 bilayers were analyzed. The Si-NCs are assumed as agglomerates of fixed oxygen vacancies, which promote the formation of conductive filaments (CFs) through the multilayer according to the simulations. In fact, an intermediate resistive state was observed in the forming process (experimental and simulated) of the 3-BL device, which is explained by the preferential generation of oxygen vacancies in the sites that form the complete CFs, through Si-NCs.

4.
Mar Pollut Bull ; 194(Pt A): 115306, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37506493

RESUMO

Cigarette butts (CB) and cigarette butt fibers (CBF) are highly abundant and frequent residues on beach sand. Also, they are hazardous waste due to their significant toxicity and potential risk to the ecosystems' biota and the health of beach tourists. This study aimed to determine the abundance and density of CB and CBF found on the active, rest, and service zones of five pilot beaches in Argentina, Colombia, Brazil, Ecuador, and Mexico. The methodology involved collecting CB and CBF in 500 m2 transects of urban tourist beaches using a citizen science-adapted methodology between June 2021 and May 2022, during the COVID-19 pandemic. The abundance and density of CB and CBF, and the Cigarette Butt Pollution Index (CBPI) were calculated. The highest proportion of CB was found in service and rest areas. Bocagrande (CO) reported the highest generation of CB and CBF and a severe CBPI.


Assuntos
COVID-19 , Produtos do Tabaco , Humanos , Areia , América Latina , Ecossistema , Pandemias , Monitoramento Ambiental , COVID-19/epidemiologia , Praias
5.
Arch Osteoporos ; 18(1): 81, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37316765

RESUMO

Osteoporosis management has become more relevant as the life expectancy increases. In Ecuador, approximately 19% of adults over 65 years of age have been diagnosed with osteoporosis. There is no national consensus for the management and prevention of the disease being this proposal the first Ecuadorian consensus. INTRODUCTION: In Ecuador, it is estimated that around 19% of adults over 65 years of age have osteoporosis. Due to the increase in life expectancy in the world population, the evaluation and management of osteoporosis has become more relevant. Currently, there is no national consensus for the management and prevention of the disease. The Ecuadorian Society of Rheumatology presented the project for the elaboration of the first Ecuadorian consensus for the management and prevention of osteoporosis. METHODS: A panel of experts in multiple areas and extensive experience was invited to participate. The consensus was carried out using the Delphi method. Six working dimensions were created: definition and epidemiology of osteoporosis, fracture risk prediction tools, non-pharmacological treatment, pharmacological treatment, calcium and vitamin D, and glucocorticoid-induced osteoporosis. RESULTS: The first round was held in December 2021, followed by the second round in February 2022 and the third round in March 2022. The data was shared with the specialists at the end of each round. After three rounds of work, a consensus was reached for the management and prevention of osteoporosis. CONCLUSION: This is the first Ecuadorian consensus for the management and treatment of postmenopausal osteoporosis.


Assuntos
Osteoporose Pós-Menopausa , Osteoporose , Adulto , Feminino , Humanos , Equador/epidemiologia , Consenso , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/terapia , Cálcio da Dieta
6.
Rev. colomb. cir ; 38(3): 483-491, Mayo 8, 2023. tab, fig
Artigo em Espanhol | LILACS | ID: biblio-1438567

RESUMO

Introducción. El manejo de las hernias se ha instaurado como un problema quirúrgico común, estimándose su aumento en los próximos años. El objetivo del presente trabajo fue describir el curso clínico, los aspectos del tratamiento quirúrgico y factores asociados a la presencia de complicaciones en pacientes intervenidos por hernia incisional. Métodos. Estudio descriptivo en el que se analizaron las características de una cohorte de pacientes llevados a corrección quirúrgica de hernia incisional en el Hospital Universitario Hernando Moncaleano Perdomo, un centro de alta complejidad en Neiva, Colombia, entre 2012 y 2019. Los datos fueron recolectados en programa Microsoft Excel® y analizados en SPSSTM, versión 21. Resultados. Se realizaron 133 correcciones de hernias incisionales, 69,9 % en mujeres y la mayoría ubicadas en la línea media (84,2 %). La edad media de los pacientes al momento de la intervención fue de 52 años ±14,6. Las comorbilidades más frecuentes fueron obesidad, hipertensión y diabetes. La causa más frecuente de la hernia fue traumática (61,7 %). La frecuencia de complicaciones fue superior al 50 %, en su mayoría menores; se encontró asociación con obesidad para la presencia de seroma. La mortalidad fue del 2,3 %. Conclusión.La hernia incisional es un problema de salud pública. Consideramos que la obesidad y el uso de malla pueden ser factores de riesgo asociados con la presentación de complicaciones postoperatorias, así como el aumento de los gastos relacionados con días de hospitalización


Introduction. Hernias management has become a common surgical problem, with an estimated increase in the coming years. The objective of this study was to describe the clinical course, aspects of surgical treatment and factors associated with the presence of complications in patients operated on for incisional hernia. Methods. Descriptive study, in which the characteristics of a cohort of patients taken to surgical correction of incisional hernia at the Hospital Universitario Hernando Moncaleano Perdomo, a high complexity medical center located in Neiva, Colombia, between 2012 and 2019 were analyzed, whose data were collected in Microsoft Excel® software and analyzed in SPSSTM, version 21. Results. One-hundred-thirty-three incisional hernia corrections were performed. The mean age at the intervention was 52 years ±14.6. The most frequent comorbidities were weight disorders, hypertension and diabetes. Only one laparoscopy was performed, the first etiology of the hernia was traumatic (61.7%) and midline (84.2%). The frequency of complications was greater than 50%, mostly minors. An association with obesity was found for the presence of seroma. Mortality was 2.3%. Conclusion. Incisional hernia is a public health problem. We consider that obesity and the use of mesh are a risk factor associated with the presentation of postoperative complications as well as the increase in costs related to days of hospitalization


Assuntos
Humanos , Hérnia Abdominal , Hérnia Incisional , Complicações Pós-Operatórias , Reoperação , Parede Abdominal , Hérnia Ventral
8.
Nanomaterials (Basel) ; 13(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36985880

RESUMO

In this work, we report the digital and analog resistive-switching (RS) characteristics in a memristor based on silicon nanocrystals (Si-NCs) integrated into a complementary metal-oxide-semiconductor (MOS) structure. Si-NCs with a diameter of 5.48 ± 1.24 nm embedded in a SiO2/Si-NCs/SiO2 multilayer structure acts as an RS layer. These devices exhibit bipolar RS with an intermediate resistance step during SET and RESET processes, which is believed to lie in the Si-NCs layer acting as charge-trapping nodes. The endurance studies of about 70 DC cycles indicate an ON/OFF ratio of ~106 and a retention time larger than 104 s. Long-term potentiation (LTP, -2 V) and long-term depression (LTD, +4 V) are obtained by applying consecutive identical pulse voltages of 150 ms duration. The current value gradually increases/decreases (LTP/LTD) as the pulse number increases. Three consecutive identical pulses of -2 V/150 ms (LTP) separated by 5 and 15 min show that the last current value obtained at the end of each pulse train is kept, confirming an analog RS behavior. These characteristics provide a possible way to mimic biological synapse functions for applications in neuromorphic computing in Si-NCs-based CMOS structures.

9.
Micromachines (Basel) ; 13(11)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36363969

RESUMO

In this work, we explored the feasibility of the fabrication of PIN light-emitting diodes (LEDs) consisting of heterojunctions of amorphous silicon-carbide (a-Si1-xCx:H) thin films and crystalline silicon wafers (c-Si). The objective is the future development of electro-photonic systems in the same c-Si wafer, containing transistors, sensors, LEDs and waveguides. Two different heterojunction LEDs were fabricated consisting of PIN and PIN+N structures, where a-Si1-xCx:H thin films were used as P-type and I-type layers, while an N-type c-Si substrate was used as an active part of the device. The amorphous layers were deposited by the plasma-enhanced chemical vapor deposition (PECVD) technique at a substrate temperature of 200 °C. The PIN device presented electroluminescence (EL) only in the forward bias, while the PIN+N device presented in both the forward and reverse biases. The EL in reverse bias was possible due to the addition of an N+-type a-Si:H layer between the c-Si substrate and the I-type a-Si1-xCx:H active layer. Likewise, the EL intensity of the PIN+N structure was higher than that of the PIN device in forward bias, indicating that the addition of the N-type a-Si:H layer makes electrons flow more efficiently to the I layer. In addition, both devices presented red EL in the full area, which is observed with the naked eye.

10.
Rev. colomb. cir ; 37(4): 612-619, 20220906. tab, fig
Artigo em Espanhol | LILACS | ID: biblio-1396401

RESUMO

Introducción. En Colombia, la tasa de mortalidad en la Unidad de Cuidados Intensivos es cercana al 32 %, por lo anterior, se han estudiado múltiples predictores de mortalidad que identifiquen de manera precoz una evolución inadecuada. La masa muscular corresponde a cerca del 50 % del peso corporal y cumple importantes funciones metabólicas, como la generación de energía y la homeostasis de la glucosa. Se ha informado la disminución de hasta el 1,6 % de la masa muscular por día en pacientes críticos, factor relacionado con la mortalidad. Métodos. Se realizó un estudio de cohorte prospectiva entre enero de 2020 y diciembre de 2021, con una muestra no probabilística a conveniencia, incluyendo a los pacientes que ingresaron a las diferentes Unidad de Cuidados Intensivos del Hospital Universitario Hernando Moncaleano Perdomo, en quienes se realizó un registro periódico de las medidas antropométricas y del grosor del musculo cuádriceps.Resultados. Se incluyeron 82 pacientes, encontrando como variables asociadas a la mortalidad la edad, el número de días de hospitalización, el índice de masa corporal y el delta del musculo cuádriceps. Una medida del grosor del musculo cuádriceps al ingreso menor de 2,5 cm, se asoció con alto riesgo de muerte y una disminución de más de 1,72 cm durante el control ecográfico se relacionó con mal pronóstico. Conclusiones. Aunque estas variables se eligieron en función de su asociación con mortalidad, nuestros resultados emplean importantes características, como la medición del grosor muscular y su delta durante la estancia en la unidad de cuidados intensivos, lo que indica un mayor consumo de las reservas fisiológicas, asociándose a mayor riesgo de complicaciones y mortalidad.


Introduction. In Colombia, the mortality rate in the Intensive Care Unit is close to 32%; therefore, multiple mortality predictors have been studied to identify an inadequate evolution early. Muscle mass corresponds to about 50% of body weight and fulfills important metabolic functions such as energy generation and glucose homeostasis. A decrease of up to 1.6% of muscle mass per day has been reported in critically ill patients, a factor related to mortality. Methods. A prospective cohort study was carried out between May and June 2020, with a non-probabilistic convenience sample, including patients admitted to the different Intensive Care Units of the Hernando Moncaleano Perdomo University Hospital, performing a periodic record of anthropometric measurements and the thickness of the quadriceps muscle. Results. 82 patients were included, finding age, number of hospital days, body mass index, and quadriceps muscle delta as variables associated with mortality. A measurement of the thickness of the quadriceps muscle at admission <2.5 cm was associated with a high risk of death and a decrease of >1.72 cm during the ultrasound control was associated with a poor prognosis. Conclusions. Although these variables were chosen based on their association with mortality, our results use important characteristics such as the measurement of muscle thickness and its delta during the stay in the intensive care unit, which indicates a greater consumption of physiological reserves associated with greater risk of complications and mortality.


Assuntos
Humanos , Sarcopenia , Unidades de Terapia Intensiva , Fatores de Risco , Mortalidade
11.
Nanomaterials (Basel) ; 12(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35745294

RESUMO

A novel method to extract the seven parameters of the double-diode model of solar cells using the current-voltage (I-V) characteristics under illumination and in the dark is presented. The algorithm consists of two subroutines which are alternatively run to adjust all the parameters of the cell in an iterative process. Curve fitting of the light I-V characteristics ensures accuracy in the prediction of the maximum power point, whereas simultaneously fitting the dark I-V characteristics results in a set of physically meaningful parameters that provide information about the physical performance of the photovoltaic devices. Experimental I-V curves of in-house solar cells are used to validate the proposed parameter extraction method, which can be furthermore applied to other types of p-n junction-based photovoltaic devices.

12.
Nanomaterials (Basel) ; 12(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35745354

RESUMO

In this work, we show a correlation between the composition and the microstructural and optical properties of bright and uniform luminescent porous silicon (PSi) films. PSi films were synthesized by electrochemical etching using nitric acid in an electrolyte solution. PSi samples synthesized with nitric acid emit stronger (up to six-fold greater) photoluminescence (PL) as compared to those obtained without it. The PL peak is shifted from 630 to 570 nm by changing the concentration ratio of the HF:HNO3:(EtOH-H2O) electrolyte solution, but also shifts with the excitation energy, indicating quantum confinement effects in the silicon nanocrystals (Si-NCs). X-ray photoelectron spectroscopy analysis shows a uniform silicon content in the PSi samples that emit the strongest PL. High-resolution transmission electron microscopy reveals that the Si-NCs in these PSi samples are about ~2.9 ± 0.76 nm in size and are embedded in a dense and stoichiometric SiO2 matrix, as indicated by the Fourier transform infrared analysis. On the other hand, the PSi films that show PL of low intensity present an abrupt change in the silicon content depth and the formation of non-bridging oxygen hole center defects.

13.
urol. colomb. (Bogotá. En línea) ; 31(1): 21-27, 15/03/2022. graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1368865

RESUMO

Introducción y Objetivo La cirugía de próstata es un procedimiento frecuente en varones mayores. Existen diferentes técnicas, cuya elección depende de la patología a tratar, de la experiencia del especialista, y de la disponibilidad técnica. Entre sus complicaciones se encuentra la infección del tracto urinario, que ocasiona incremento en morbimortalidad y costos para el sistema de salud. El objetivo principal de este estudio fue evaluar los factores relacionados con la aparición de infección urinaria luego de este tipo de cirugía. Materiales y Métodos Se realizó un estudio de casos y controles en una población de pacientes sometidos a prostatectomía del 2018 hasta principios del 2020 en Medellín, Colombia. Los casos correspondieron a los pacientes que presentaron infección de vías urinarias hasta 30 días tras la prostatectomía. Se estimó la asociación entre casos y controles por medio del cálculo de la razón de disparidad (RD), la cual se ajustó con una regresión logística y con un modelo aditivo generalizado multivariado. Resultados Se identificaron 96 casos incidentes de infección del trato urinario luego de la prostatectomía, con una prevalencia de 8.99%. La frecuencia de solicitud de urocultivo preoperatorio fue de 52,92% (intervalo de confianza del 95% [IC95%]: 48,34­ 57,44%). Las variables independientemente asociadas con la aparición de infección urinaria fueron: solicitud de urocultivo prequirúrgico, número de dosis, y tipo de antibiótico usado para la profilaxis. Particularmente, se encontró como factor protector el uso de aminoglucósidos. En los pacientes con infección urinaria, los principales gérmenes aislados fueron: Eschirichia coli, Pseudomonas aeruginosa, Klepsiella pneumoniae, Enterococos faecalis y Serratia marcescens.


Introduction and Objective Prostate surgery is a common procedure among older men. There are different techniques, and the choice depends on the pathology to be treated, the experience of the specialist, and the technical availability. Among its complications is urinary tract infection, which causes increased morbidity and mortality and costs for the health system. The main objective of the present study was to evaluate the factors related to the onset of urinary tract infection after prostate surgery. Materials and Methods A case-control study was conducted in a population of patients undergoing prostatectomy from 2018 to early 2020 in the city of Medellín, Colombia. The cases corresponded to patients who presented urinary tract infection up to 30 days after prostatectomy. The association between cases and controls was estimated by calculating the odds ratio (OR), which was adjusted with logistic regression and a multivariate generalized additive model. Results We identified 96 incident cases of urinary tract infection after prostatectomy, with a prevalence of 8.99%. The frequency of requests for preoperative urine culture was of 52.92% (95% confidence interval [95%CI]: 48.34 - 57.44). The independently associated variables were: request for preoperative urine culture, number of doses, and type of antibiotic used for prophylaxis. In particular, the use of aminoglycosides in prophylaxis schemes was found to be a protective factor. The main germs isolated were: Eschirichia coli, Pseudomonas aeruginosa, Klepsiella pneumoniae, Enterococos faecalis, and Serratia marcescens. Conclusion The present study shows that factors such as the preoperative request for urine culture and the use of aminoglycosides for surgical prophylaxis influence the probability of developing urinary tract infection after prostatectomy.


Assuntos
Humanos , Masculino , Prostatectomia , Sistema Urinário , Infecções Urinárias , Pseudomonas aeruginosa , Serratia marcescens , Indicadores de Morbimortalidade , Fatores de Proteção , Aminoglicosídeos , Antibacterianos
14.
Materials (Basel) ; 14(21)2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34772107

RESUMO

Two multilayer (ML) structures, composed of five layers of silicon-rich oxide (SRO) with different Si contents and a sixth layer of silicon-rich nitride (SRN), were deposited by low pressure chemical vapor deposition. These SRN/SRO MLs were thermally annealed at 1100 °C for 180 min in ambient N2 to induce the formation of Si nanostructures. For the first ML structure (MLA), the excess Si in each SRO layer was about 10.7 ± 0.6, 9.1 ± 0.4, 8.0 ± 0.2, 9.1 ± 0.3 and 9.7 ± 0.4 at.%, respectively. For the second ML structure (MLB), the excess Si was about 8.3 ± 0.2, 10.8 ± 0.4, 13.6 ± 1.2, 9.8 ± 0.4 and 8.7 ± 0.1 at.%, respectively. Si nanopyramids (Si-NPs) were formed in the SRO/Si substrate interface when the SRO layer with the highest excess silicon (10.7 at.%) was deposited next to the MLA substrate. The height, base and density of the Si-NPs was about 2-8 nm, 8-26 nm and ~6 × 1011 cm-2, respectively. In addition, Si nanocrystals (Si-ncs) with a mean size of between 3.95 ± 0.20 nm and 2.86 ± 0.81 nm were observed for the subsequent SRO layers. Meanwhile, Si-NPs were not observed when the excess Si in the SRO film next to the Si-substrate decreased to 8.3 ± 0.2 at.% (MLB), indicating that there existed a specific amount of excess Si for their formation. Si-ncs with mean size of 2.87 ± 0.73 nm and 3.72 ± 1.03 nm were observed for MLB, depending on the amount of excess Si in the SRO film. An enhanced photoluminescence (PL) emission (eight-fold more) was observed in MLA as compared to MLB due to the presence of the Si-NPs. Therefore, the influence of graded silicon content in SRN/SRO multilayer structures on the formation of Si-NPs and Si-ncs, and their relation to the PL emission, was analyzed.

15.
Materials (Basel) ; 14(22)2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34832349

RESUMO

Hydrogenated microcrystalline silicon (µc-Si:H) and epitaxial silicon (epi-Si) films have been produced from SiF4, H2 and Ar mixtures by plasma enhanced chemical vapor deposition (PECVD) at 200 °C. Here, both films were produced using identical deposition conditions, to determine if the conditions for producing µc-Si with the largest crystalline fraction (XC), will also result in epi-Si films that encompass the best quality and largest crystalline silicon (c-Si) fraction. Both characteristics are of importance for the development of thin film transistors (TFTs), thin film solar cells and novel 3D devices since epi-Si films can be grown or etched in a selective manner. Therefore, we have distinguished that the H2/SiF4 ratio affects the XC of µc-Si, the c-Si fraction in epi-Si films, and the structure of the epi-Si/c-Si interface. Raman and UV-Vis ellipsometry were used to evaluate the crystalline volume fraction (Xc) and composition of the deposited layers, while the structure of the films were inspected by high resolution transmission electron microscopy (HRTEM). Notably, the conditions for producing µc-Si with the largest XC are different in comparison to the fabrication conditions of epi-Si films with the best quality and largest c-Si fraction.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34207231

RESUMO

Early childhood is a critical period for obesity prevention. This randomized controlled study evaluated the effectiveness of an educational intervention preventing obesity in preschool-age children. A nutritional education intervention, with a follow-up session one year later, was conducted with parents of children aged 3 to 4 years of public schools in the province of Málaga. The main outcome variable was the body mass index z-score (zBMI). The prevalence of overweight or obesity was the secondary outcome variable. The sample comprised 261 students (control group = 139). Initial BMI, weight, height-for-age and prevalence of overweight and obesity were similar for both groups. After the first year of the intervention, the zBMI of the intervention group decreased significantly from 0.23 to 0.10 (p = 0.002), and the subgroup of patients with baseline zBMI above the median decreased from 1 to 0.72 (p = 0.001), and in the second year from 1.01 to 0.73 (p = 0.002). The joint prevalence of overweight and obesity increased in the control group (12.2% to 20.1%; p = 0.027), while in the intervention group, there were no significant changes. This preschool educational intervention with parents improved their children's BMI, especially those with a higher BMI for their age, and favored the prevention of overweight or obesity.


Assuntos
Obesidade Infantil , Índice de Massa Corporal , Criança , Pré-Escolar , Educação em Saúde , Humanos , Sobrepeso/epidemiologia , Sobrepeso/prevenção & controle , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Instituições Acadêmicas
20.
Sensors (Basel) ; 21(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068486

RESUMO

The applicability of the path planning strategy to robotic manipulators has been an exciting topic for researchers in the last few decades due to the large demand in the industrial sector and its enormous potential development for space, surgical, and pharmaceutical applications. The automation of high-degree-of-freedom (DOF) manipulator robots is a challenging task due to the high redundancy in the end-effector position. Additionally, in the presence of obstacles in the workspace, the task becomes even more complicated. Therefore, for decades, the most common method of integrating a manipulator in an industrial automated process has been the demonstration technique through human operator intervention. Although it is a simple strategy, some drawbacks must be considered: first, the path's success, length, and execution time depend on operator experience; second, for a structured environment with few objects, the planning task is easy. However, for most typical industrial applications, the environments contain many obstacles, which poses challenges for planning a collision-free trajectory. In this paper, a multiple-query method capable of obtaining collision-free paths for high DOF manipulators with multiple surrounding obstacles is presented. The proposed method is inspired by the resistive grid-based planner method (RGBPM). Furthermore, several improvements are implemented to solve complex planning problems that cannot be handled by the original formulation. The most important features of the proposed planner are as follows: (1) the easy implementation of robotic manipulators with multiple degrees of freedom, (2) the ability to handle dozens of obstacles in the environment, (3) compatibility with various obstacle representations using mathematical models, (4) a new recycling of a previous simulation strategy to convert the RGBPM into a multiple-query planner, and (5) the capacity to handle large sparse matrices representing the configuration space. A numerical simulation was carried out to validate the proposed planning method's effectiveness for manipulators with three, five, and six DOFs on environments with dozens of surrounding obstacles. The case study results show the applicability of the proposed novel strategy in quickly computing new collision-free paths using the first execution data. Each new query requires less than 0.2 s for a 3 DOF manipulator in a configuration space free-modeled by a 7291 × 7291 sparse matrix and less than 30 s for five and six DOF manipulators in a configuration space free-modeled by 313,958 × 313,958 and 204,087 × 204,087 sparse matrices, respectively. Finally, a simulation was conducted to validate the proposed multiple-query RGBPM planner's efficacy in finding feasible paths without collision using a six-DOF manipulator (KUKA LBR iiwa 14R820) in a complex environment with dozens of surrounding obstacles.

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