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1.
Ultrason Sonochem ; 105: 106870, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38579570

RESUMEN

The obtained seeds from fruit processing are considered by-products containing proteins that could be utilized as ingredients in food manufacturing. However, in the specific case of soursop seeds, their usage for the preparation of protein isolates is limited. In this investigation a protein isolate from soursop seeds (SSPI) was obtained by alkaline extraction and isoelectric precipitation methods. The SSPI was sonicated at 200, 400 and 600 W during 15 and 30 min and its effect on the physicochemical, functional, biochemical, and structural properties was evaluated. Ultrasound increased (p < 0.05) up to 5 % protein content, 261 % protein solubility, 60.7 % foaming capacity, 30.2 % foaming stability, 86 % emulsifying activity index, 4.1 % emulsifying stability index, 85.4 % in vitro protein digestibility, 423.4 % albumin content, 83 % total sulfhydryl content, 316 % free sulfhydryl content, 236 % α-helix, 46 % ß-sheet, and 43 % ß-turn of SSPI, in comparison with the control treatment without ultrasound. Furthermore, ultrasound decreased (p < 0.05) up to 50 % particle size, 37 % molecular flexibility, 68 % surface hydrophobicity, 41 % intrinsic florescence spectrum, and 60 % random coil content. Scanning electron microscopy analysis revealed smooth structures of the SSPI with molecular weights ranging from 12 kDa to 65 kDa. The increase of albumins content in the SSPI by ultrasound was highly correlated (r = 0.962; p < 0.01) with the protein solubility. Improving the physicochemical, functional, biochemical and structural properties of SSPI by ultrasound could contribute to its utilization as ingredient in food industry.


Asunto(s)
Annona , Proteínas de Plantas , Semillas , Solubilidad , Semillas/química , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Annona/química , Ondas Ultrasónicas , Fenómenos Químicos , Sonicación
2.
Eur J Psychotraumatol ; 14(2): 2263313, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37815059

RESUMEN

BACKGROUND: ICD-11 Posttraumatic Stress Disorder (PTSD) and Complex PTSD (CPTSD) are stress-related disorders. The International Trauma Questionnaire (ITQ) is a widely used instrument to assess PTSD and CPTSD. To date, there is no evidence of the psychometric characteristics of the ITQ in Latin American countries. OBJECTIVE: The aim of this study was to assess the construct and concurrent validity of the Latin American Spanish adaptation of the ITQ in a sample of Chilean adults. METHODS: A sample of 275 Chilean young adults completed the ITQ, a traumatic life events checklist, the Adverse Childhood Experiences Questionnaire, the Depression Anxiety Stress Scales-21, and the Columbia-Suicide Severity Rating Scale short version. Four alternative confirmatory factor analysis models were tested. Correlation analyses were performed to determine concurrent validity with associated measures (number of reported traumatic events, number of adverse childhood experiences, anxiety, depression, and suicidal risk). RESULTS: The second-order two-factor (PTSD and DSO) and the correlated first-order six-factor model provided acceptable fit; however, the first model showed a better fit based on the BIC difference. The PTSD and DSO dimensions, as well as the six ITQ clusters showed positive correlations with reported number of traumatic life-events, reported number of adverse childhood experiences, levels of anxiety, depression, and suicidal risk. CONCLUSIONS: The ITQ Latin American Spanish adaptation provides acceptable psychometric evidence to assess PTSD and CPTSD in accordance with the ICD-11.


This study is an initial validation of the Latin American Spanish adaptation of the ITQ with a Chilean young adults sample.The latent structure of the Latin American Spanish ITQ was better supported by a two-factor second-order model (PTSD/DSO); a six-factor correlated model was also acceptable.The six ITQ symptom clusters, as well as the PTSD/CPTSD dimensions were significantly positively correlated with three criterion variables: anxiety, depression, and suicidal risk.The number of potentially traumatic experiences, as well as number of exposure to adverse childhood experiences, was significantly associated with PTSD/CPTSD symptoms.


Asunto(s)
Trastornos por Estrés Postraumático , Adulto Joven , Humanos , Chile , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/epidemiología , Encuestas y Cuestionarios , Ansiedad/diagnóstico , Trastornos de Ansiedad
3.
Acta Psychol (Amst) ; 240: 104056, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37865000

RESUMEN

Past research has yielded conflicting findings concerning socio-cognitive deficits in individuals with autistic traits. This raises the fundamental question whether autistic traits and socio-cognitive abilities are related. The present study investigated whether three key socio-cognitive abilities-imitation-inhibition, empathy, and emotion regulation-can serve as predictive factors for autistic traits within a neurotypical population. Participants (N = 166, Mage = 24.83 years, SDage = 5.20 years, rangeage = 18 to 39 years) were asked to perform an online imitation-inhibition task and complete self-report measures assessing empathy, emotion regulation, and autistic traits. Empathy was measured using the Interpersonal Reactivity Index (IRI), emotion regulation was assessed using the Difficulties in Emotion Regulation Scale (DERS), and autistic traits were measured using the ten-item short form of the Autism-Spectrum Quotient (AQ-10). Multiple regression analyses revealed that both imitation-inhibition and emotion regulation were significantly associated with autistic traits. However, empathy was not found to be a significant predictor. Our study aimed to clarify inconsistent results regarding the relationship between socio-cognitive abilities and autistic traits.


Asunto(s)
Trastorno Autístico , Humanos , Adulto Joven , Adulto , Preescolar , Adolescente , Trastorno Autístico/psicología , Cognición Social , Empatía , Cognición
4.
Nanomaterials (Basel) ; 13(5)2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36903684

RESUMEN

For optoelectronic devices from the near to the far infrared, the advantages of using ultrathin III-Sb layers as quantum wells or in superlattices are well known. However, these alloys suffer from severe surface segregation problems, so that the actual profiles are very different from the nominal ones. Here, by inserting AlAs markers within the structure, state-of-the-art transmission electron microscopy techniques were used to precisely monitor the incorporation/segregation of Sb in ultrathin GaAsSb films (from 1 to 20 monolayers (MLs)). Our rigorous analysis allows us to apply the most successful model for describing the segregation of III-Sb alloys (three-layer kinetic model) in an unprecedented way, limiting the number of parameters to be fitted. The simulation results show that the segregation energy is not constant throughout the growth (which is not considered in any segregation model) but has an exponential decay from 0.18 eV to converge asymptotically towards 0.05 eV. This explains why the Sb profiles follow a sigmoidal growth model curve with an initial lag in Sb incorporation of 5 MLs and would be consistent with a progressive change in surface reconstruction as the floating layer is enriched.

5.
PLoS One ; 17(11): e0276970, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36441720

RESUMEN

Voluntary isolation is one of the most effective methods for individuals to help prevent the transmission of diseases such as COVID-19. Understanding why people leave their homes when advised not to do so and identifying what contextual factors predict this non-compliant behavior is essential for policymakers and public health officials. To provide insight on these factors, we collected data from 42,169 individuals across 16 countries. Participants responded to items inquiring about their socio-cultural environment, such as the adherence of fellow citizens, as well as their mental states, such as their level of loneliness and boredom. We trained random forest models to predict whether someone had left their home during a one week period during which they were asked to voluntarily isolate themselves. The analyses indicated that overall, an increase in the feeling of being caged leads to an increased probability of leaving home. In addition, an increased feeling of responsibility and an increased fear of getting infected decreased the probability of leaving home. The models predicted compliance behavior with between 54% and 91% accuracy within each country's sample. In addition, we modeled factors leading to risky behavior in the pandemic context. We observed an increased probability of visiting risky places as both the anticipated number of people and the importance of the activity increased. Conversely, the probability of visiting risky places increased as the perceived putative effectiveness of social distancing decreased. The variance explained in our models predicting risk ranged from < .01 to .54 by country. Together, our findings can inform behavioral interventions to increase adherence to lockdown recommendations in pandemic conditions.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias , Control de Enfermedades Transmisibles , Aprendizaje Automático , Distanciamiento Físico
6.
Nanomaterials (Basel) ; 12(22)2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36432312

RESUMEN

A series of six polybenzylic dendrons with an alkynyl focal point were synthesized for their incorporation to gold nanoparticles. Five of these compounds showed columnar mesomorphism in a wide range of temperatures. These dendrons were reacted with gold nanoparticles stabilized with a combination of a dodecanethiol and 11-azidoundecane-1-thiol. The azido group of the last compound allowed the functionalization of the nanoparticles with the six polybenzylic dendrons by 1,3-dipolar cycloaddition between their alkynyl groups and the terminal azido groups of the thiols. A high efficiency of the cycloaddition process (47-69%) was confirmed by several experimental techniques and no decomposition or aggregation phenomena were detected in the dendron-coated nanoparticles. The involved mechanism and the resulting percentage composition of the final materials are discussed. The results of the ulterior growth of the nanoparticles by thermal treatment are influenced by the size and the shape of the dendron and the temperature of the process. The structures of the final nanoparticles were investigated by TEM, DSC, TGA, NMR and UV-Vis spectroscopy. These nanoparticles do not show liquid crystal properties. However, a melting process between a crystalline and a fluid phase is observed. In the solid phase, the nanomaterials prepared show a short-range interaction between nanoparticles with a 2D local hexagonal order. A near-field effect was observed in the UV-vis spectra by coupling of different surface plasmon resonance bands (SPR) probably due to the short-range interactions. The main novelty of this work lies in the scarcity of previous studies of gold nanoparticles coated with dendrons forming themselves columnar mesophases. Most of the studies reported in the literature deal with gold nanoparticles coated with calamitic mesogens. Additionally, the effect of the thermal treatment, which in a previous paper was shown to increase the mean size of the nanoparticles without increasing their size polydispersity, has been studied in these materials.

7.
Behav Brain Sci ; 45: e294, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36396396

RESUMEN

Dubourg and Baurmard ask why people consume fiction with imaginary worlds. We extend this inquiry to ask why people engage in creating imaginary worlds. In Fanfiction, the writing of fiction by fans involves both an immersive creative experience and a very interactive community that may explain the high (social) engagement of people with Fanfiction.

8.
Nanomaterials (Basel) ; 12(14)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35889728

RESUMEN

The use of thin AlA capping layers (CLs) on InAs quantum dots (QDs) has recently received considerable attention due to improved photovoltaic performance in QD solar cells. However, there is little data on the structural changes that occur during capping and their relation to different growth conditions. In this work, we studied the effect of AlA capping growth rate (CGR) on the structural features of InAs QDs in terms of shape, size, density, and average content. As will be shown, there are notable differences in the characteristics of the QDs upon changing CGR. The Al distribution analysis in the CL around the QDs was revealed to be the key. On the one hand, for the lowest CGR, Al has a homogeneous distribution over the entire surface, but there is a large thickening of the CL on the sides of the QD. As a result, the QDs are lower, lenticular in shape, but richer in In. On the other hand, for the higher CGRs, Al accumulates preferentially around the QD but with a more uniform thickness, resulting in taller QDs, which progressively adopt a truncated pyramidal shape. Surprisingly, intermediate CGRs do not improve either of these behaviors, resulting in less enriched QDs.

9.
Front Psychiatry ; 13: 926556, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35832591

RESUMEN

Psychotic experiences (PEs) are prevalent in the general population, particularly in adolescents. PEs are associated with various negative outcomes such as psychotic, depressive, anxiety and post-traumatic stress disorders and suicidal behavior. Recent studies in the general population have suggested that what makes PEs relevant is not so much the experiences per se, but their association with non-psychotic comorbidity and other transdiagnostic domains. Thus, there is a need for a better understanding of how PEs exist in a larger psychopathological context in adolescents. In the present study we aimed to explore this, using latent profile analysis (LPA) to identify different patterns in which PEs, psychiatric symptoms and psychological processes co-occur. LPA was conducted using data from an adolescent general population subsample (n = 335) with PEs. We conducted LPA, using measures of PEs, psychiatric symptoms and behaviors (depression, anxiety post-traumatic stress disorder and suicidal behavior) and cognitive and affective processes of entrapment/defeat and emotional regulation as manifest variables. We found that the best fit was obtained with a four-class solution that distinguished primarily between different levels of overall severity: "low symptomatology" (19.1%), "mild-moderate symptomatology" (39.4%), "moderate symptomatology" (33.7%); "high symptomatology" (7.8%). Levels of depression, post-traumatic stress symptoms and defeat/entrapment were most differentiated between classes. The high symptomatology group showed the highest scores in all psychiatric symptoms suicidal ideation, and emotional/cognitive domains, except in cognitive reappraisal. This group also showed the highest usage of emotional suppression. Our results suggest that the assessment of mental health risk in adolescents should be aware that PEs exist in a broad context of other domains of psychopathology and transdiagnostic cognitive and affective processes.

10.
Nanomaterials (Basel) ; 12(8)2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35458076

RESUMEN

Recently, thin AlAs capping layers (CLs) on InAs quantum dot solar cells (QDSCs) have been shown to yield better photovoltaic efficiency compared to traditional QDSCs. Although it has been proposed that this improvement is due to the suppression of the capture of photogenerated carriers through the wetting layer (WL) states by a de-wetting process, the mechanisms that operate during this process are not clear. In this work, a structural analysis of the WL characteristics in the AlAs/InAs QD system with different CL-thickness has been made by scanning transmission electron microscopy techniques. First, an exponential decline of the amount of InAs in the WL with the CL thickness increase has been found, far from a complete elimination of the WL. Instead, this reduction is linked to a higher shield effect against QD decomposition. Second, there is no compositional separation between the WL and CL, but rather single layer with a variable content of InAlGaAs. Both effects, the high intermixing and WL reduction cause a drastic change in electronic levels, with the CL making up of 1-2 monolayers being the most effective configuration to reduce the radiative-recombination and minimize the potential barriers for carrier transport.

11.
Ultrason Sonochem ; 84: 105976, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35272239

RESUMEN

In this study, the influence of ultrasound on the physicochemical and functional properties of guamuchil seed protein isolate (GSPI) was investigated. The GSPI was prepared by alkaline extraction and isoelectric precipitation method followed by treating with ethanol (95%), from defatted guamuchil seed flour. GSPI suspensions (10%) were sonicated with a probe (20 kHz) at 3 power levels (200 W, 400 W, 600 W) for 15 and 30 min, in addition, to control treatment without ultrasound. Moisture content, water activity, bulk and compact densities and the L*, a* and b* color parameters of the GSPI decreased due to the ultrasound. Glutelin (61.1%) was the main protein fraction in GSPI. Results through Fourier transform infrared and fluorescence spectroscopy showed that ultrasound modified the secondary and tertiary protein structures of GSPI, which increased the surface hydrophobicity, molecular flexibility and in vitro digestibility of GSPI proteins by up to 114.8%, 57.3% and 12.5%, respectively. In addition, maximum reductions of 11.9% in particle size and 55.2% in turbidity of GSPI suspensions, as well as larger and more porous aggregates in GSPI lyophilized powders were observed by ultrasound impact. These structural and physicochemical changes had an improvement of up to 115.5% in solubility, 39.8% in oil absorption capacity, while the increases for emulsifying, foaming, gelling, flow and cohesion properties of GSPI were 87.4%, 74.2%, 40.0%, 44.4%, and 8.9%, respectively. The amelioration of the functional properties of GSPI by ultrasound could represent an alternative for its possible use as a food ingredient in industry.


Asunto(s)
Fabaceae , Proteínas de Plantas , Fenómenos Químicos , Proteínas de Plantas/química , Semillas/química , Solubilidad
12.
Arch Esp Urol ; 74(7): 656-663, 2021 Sep.
Artículo en Español | MEDLINE | ID: mdl-34472434

RESUMEN

OBJECTIVE: To determine predictors of BCR in patients with localized PCa undergoing RP at an oncology reference center in Colombia. MATERIALS AND METHODS: A retrospective analytical study was conducted on patients with localized PCa undergoing RP and who at least had one adverse pathological factor for BCR. We consider BCR as two consecutive elevations of PSA after RP, greater than 0.2 ng/ml. For the bivariate analysis we used Kaplan-Meier, and Cox proportional risk analysis to estimate the hazard ratio as well as to determine variables independently associated with the outcome. RESULTS: 280 patients were included. The medianage was 65.3 years, with a median follow up of 52.2 months. BCR occurred in 39% of patients, with a median BCR time of 24.8 months. In the multivariate analysis, high risk [HR 2.07 (95% CI 1.11 - 3.86)], positive surgical margins [HR 2.79 (95% CI 1.66 - 4.69)] and tertiary Gleason pattern [HR 2.16 (95% CI 1.16 - 4.01)] were identified as independent variables associated significantly with BCR. Limitations include retrospective design and sample size. CONCLUSIONS: High risk, positive surgical margins and the presence of tertiary Gleason pattern are the predictive factors of BCR after RP in the Colombian population.


OBJETIVO: Determinar los predictores de recaída bioquímica en pacientes con cáncer de próstata localizado llevados a prostatectomía radical en un centro oncológico de referencia en Colombia.MATERIALES Y MÉTODOS: Se realizó un estudio retrospectivo analítico en pacientes con cáncer de próstata localizado que fueron llevados a prostatectomía radical y que tuvieran al menos un factor patológico adverso para recaída bioquímica. Las variables analizadas fueron la edad, el riesgo, el estadio pT, el estadio pN, la densidad ganglionar, los márgenes quirúrgicos, el grupo grado de Gleason y el patrón terciario del Gleason. Consideramos recaída bioquímica como 2 elevaciones consecutivas del PSA después de la prostatectomía radical, mayor a 0,2 ng/ml. Para el análisis bivariado usamos Kaplan-Meier y el análisis de riesgo proporcional de Cox para estimar el HR así como para determinarlas variables independientemente asociadas con el desenlace. RESULTADOS: Se incluyeron 280 pacientes. La edad promedio fue de 65,3 años, con una media de seguimiento de 52,2 meses. La recaída bioquímica ocurrió en el 39% de los pacientes, con una media de tiempo hasta la recaída bioquímica de 24,8 meses. En el análisis multivariado, el riesgo alto [HR 2,07 (IC95% 1,11­ 3,86)], los márgenes quirúrgicos positivos [HR 2,79 (IC95% 1,66 ­ 4,69)] y el patrón terciario del Gleason [HR 2,16 (IC 95% 1,16 ­ 4,01)] fueron identificados como variables independientes asociadas significativamente con recaída bioquímica. Las limitaciones incluyen el diseño retrospectivo del estudio y el tamaño de la muestra. CONCLUSIONES: El riesgo alto, los márgenes quirúrgicos positivos y la presencia de patrón terciario de Gleason son las variables predictoras de recaída bioquímica después de prostatectomía radical en la población colombiana.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Colombia , Humanos , Masculino , Clasificación del Tumor , Recurrencia Local de Neoplasia/epidemiología , Prostatectomía , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos
13.
Arch. esp. urol. (Ed. impr.) ; 74(7): 656-663, Sep 28, 2021. ilus, tab
Artículo en Español | IBECS | ID: ibc-219182

RESUMEN

Objetivo: Determinar los predictores derecaída bioquímica en pacientes con cáncer de próstata localizado llevados a prostatectomía radical en uncentro oncológico de referencia en Colombia.Materiales y métodos: Se realizó un estudio retrospectivo analítico en pacientes con cáncer de próstatalocalizado que fueron llevados a prostatectomía radicaly que tuvieran al menos un factor patológico adversopara recaída bioquímica. Las variables analizadas fueron la edad, el riesgo, el estadio pT, el estadio pN, ladensidad ganglionar, los márgenes quirúrgicos, el grupo grado de Gleason y el patrón terciario del Gleason. Consideramos recaída bioquímica como 2 elevacionesconsecutivas del PSA después de la prostatectomía radical, mayor a 0,2 ng/ml. Para el análisis bivariado usamos Kaplan-Meier y el análisis de riesgo proporcionalde Cox para estimar el HR así como para determinarlas variables independientemente asociadas con el desenlace.Rresultados: Se incluyeron 280 pacientes. La edadpromedio fue de 65,3 años, con una media de seguimiento de 52,2 meses. La recaída bioquímica ocurrióen el 39% de los pacientes, con una media de tiempohasta la recaída bioquímica de 24,8 meses. En el análisis multivariado, el riesgo alto [HR 2,07 (IC95% 1,11– 3,86)], los márgenes quirúrgicos positivos [HR 2,79(IC95% 1,66 – 4,69)] y el patrón terciario del Gleason[HR 2,16 (IC 95% 1,16 – 4,01)] fueron identificadoscomo variables independientes asociadas significativamente con recaída bioquímica. Las limitaciones incluyenel diseño retrospectivo del estudio y el tamaño de lamuestra.Conclusiones: El riesgo alto, los márgenes quirúrgicos positivos y la presencia de patrón terciario deGleason son las variables predictoras de recaída bioquímica después de prostatectomía radical en la población colombiana.(AU)


Objetive: To determine predictors ofBCR in patients with localized PCa undergoing RP at anoncology reference center in Colombia.Materiales ymethods: A retrospective analyticalstudy was conducted on patients with localized PCa undergoing RP and who at least had one adverse pathological factor for BCR. We consider BCR as two consecutive elevations of PSA after RP, greater than 0.2 ng/ml.For the bivariate analysis we used Kaplan-Meier, andCox proportional risk analysis to estimate the hazardratio as well as to determine variables independentlyassociated with the outcome.Results: 280 patients were included. The medianage was 65.3 years, with a median follow up of 52.2months. BCR occurred in 39% of patients, with a median BCR time of 24.8 months. In the multivariate analysis,high risk [HR 2.07 (95% CI 1.11 – 3.86)], positive surgical margins [HR 2.79 (95% CI 1.66 – 4.69)] and tertiary Gleason pattern [HR 2.16 (95% CI 1.16 – 4.01)were identified as independent variables associatedsignificantly with BCR. Limitations include retrospectivedesign and sample size.Conclusions: High risk, positive surgical marginsand the presence of tertiary Gleason pattern are thepredictive factors of BCR after RP in the Colombian population.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Prostatectomía , Recurrencia , Neoplasias de la Próstata , Colombia , Estudios Retrospectivos
14.
Adv Mater ; 33(36): e2101590, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34302406

RESUMEN

Tackling the interfacial loss in emerged perovskite-based solar cells (PSCs) to address synchronously the carrier dynamics and the environmental stability, has been of fundamental and viable importance, while technological hurdles remain in not only creating such interfacial mediator, but the subsequent interfacial embedding in the active layer. This article reports a strategy of interfacial embedding of hydrophobic fluorinated-gold-clusters (FGCs) for highly efficient and stable PSCs. The p-type semiconducting feature enables the FGC efficient interfacial mediator to improve the carrier dynamics by reducing the interfacial carrier transfer barrier and boosting the charge extraction at grain boundaries. The hydrophobic tails of the gold clusters and the hydrogen bonding between fluorine groups and perovskite favor the enhancement of environmental stability. Benefiting from these merits, highly efficient formamidinium lead iodide PSCs (champion efficiency up to 24.02%) with enhanced phase stability under varied relative humidity (RH) from 40% to 95%, as well as highly efficient mixed-cation PSCs with moisture stability (RH of 75%) over 10 000 h are achieved. It is thus inspiring to advance the development of highly efficient and stable PSCs via interfacial embedding laser-generated additives for improved charge transfer/extraction and environmental stability.

15.
ACS Omega ; 6(1): 348-357, 2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33458486

RESUMEN

Monodisperse dendrimer-coated gold nanoparticles with a spherical shape have been obtained by direct reduction of HAuCl4 with sodium borohydride in the presence of dodecanethiol as a stabilizer and subsequent functionalization by ligand exchange reaction with polybenzylic thiolated dendrons. The substitution pattern of the dendrimeric units plays a fundamental role in the rate of the functionalization exchange process and consequently conditions the size and the polydispersity of the NPs obtained. An ulterior growth process occurs by thermal stimuli (150 °C) in a solvent-free environment. This method, carried out in mild conditions, allows the formation of highly monodisperse gold NPs with different sizes for different time reactions, and we discuss the mechanisms involved in this process. Finally, we demonstrate the chemical composition and stability of our compounds by structural, thermal, and chemical characterization of the samples before and after thermal treatment.

16.
Rev. méd. hered ; 32(1): 5-11, ene-mar 2021. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1251957

RESUMEN

RESUMEN Objetivo: Describir las características clínicas prenatales y post natales de los neonatos hijos de madres con la Covid-19, y seguimiento hasta los 14 días post alta. Material y métodos: Estudio tipo observacional, serie de casos, censal de los neonatos nacidos en el Hospital Guillermo Almenara Irigoyen, hijos de madres con la Covid-19, que nacieron durante la cuarentena decretada por el gobierno peruano. Los neonatos se dividieron en 2 grupos: con la prueba PCR nasofaríngea positiva o no y se observó si alguna de estas características estuvieron asociadas con la presentación de esta prueba positiva. Resultados: Hubieron 201 gestantes con diagnóstico de Covid-19 por prueba rápida y que tuvieron 206 neonatos. De ellos, 4 neonatos tuvieron la PCR nasofaríngea positiva y 202, negativa. La edad materna fue menor en el grupo con la prueba positiva, pero no hubo diferencia respecto al tipo de parto: césarea, fueron a termino, con adecuado peso al nacer y ningún sexo predominó. Doscientos cinco (99,51%) neonatos salieron de alta en la primera semana de vida; 181 (90,05%) neonatos con PCR nasofaríngea negativa y los 4 neonatos con prueba positiva fueron seguidos por 2 semanas; ninguno presentó síntomas y el tipo de lactancia fue mixta. Conclusiones: Los neonatos hijos de madres con la Covid-19, tendrían una mínima posibilidad de contraer esta enfermedad. Y su desarrollo prenatal y post natal no se vería afectado, a pesar de incluso tener la prueba PCR nasofaríngea positiva.


SUMMARY Objective: To describe prenatal and post-natal clinical features of neonates born from mothers with COVID-19 including 14-day follow-up post discharge. Methods: Case series of neonates attended at Hospital Guillermo Almenara born from mothers infected with COVID-19 during the lockdown implemented by the Peruvian government. Neonates were divided in two groups based on positivity of the nasopharyngeal PCR test. Results: 201 pregnant women with COVID-19 diagnosed by rapid tests who delivered 206 neonates were identified; 4 of these neonates had positive nasopharyngeal PCR tests. Pregnants infected with COVID-19 were younger than non-infected, but no differences were observed in route of delivery, sex of the newborn and body weight at birth. Two hundred and five neonates were discharged one week after birth ;181 neonates with negative nasopharyngeal negative PCR tests and 4 neonates with a positive PCR test were followed for 14 days, none presented symptoms and received mixed lactation. Conclusions: Neonates born from mother infected with COVID-19 had minimal risk of getting the infection and their pre and post-natal development will not be affected despite of having a positive PCR test.

17.
Front Hum Neurosci ; 15: 787157, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35111006

RESUMEN

The ability to perform movements is vital for our daily life. Our actions are embedded in a complex environment where we need to deal efficiently in the face of unforeseen events. Neural oscillations play an important role in basic sensorimotor processes related to the execution and preparation of movements. In this review, I will describe the state of the art regarding the role of motor gamma oscillations in the control of movements. Experimental evidence from electrophysiological studies has shown that motor gamma oscillations accomplish a range of functions in motor control beyond merely signaling the execution of movements. However, these additional aspects associated with motor gamma oscillation remain to be fully clarified. Future work on different spatial, temporal and spectral scales is required to further understand the implications of gamma oscillations in motor control.

18.
J Phys Chem C Nanomater Interfaces ; 125(37): 20482-20487, 2021 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-35774116

RESUMEN

Highly sensitive magnetometry reveals paramagnetism in dendrimer-coated gold nanoparticles. Different types of such nanoparticles, as a result of (i) functionalizing with two distinct Percec-type dendrons, linked to gold via dodecanethiol groups, and (ii) postsynthesis annealing in a solvent-free environment that further promotes their growth have been prepared. Ultimately, for each of the two functionalization configurations, we obtain highly monodisperse and stable nanoparticles of two different sizes, with spherical shape. These characteristics allow singling out the source of the measured paramagnetic signals as exclusively arising from the undercoordinated gold atoms on the surfaces of the nanoparticles. Bulk gold and the functional groups of the ligands contribute only diamagnetically.

19.
Rev. colomb. cienc. pecu ; 33(3): 195-201, July-Sept. 2020. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1351946

RESUMEN

Abstract Background: Coccidiosis is the infectious disease with the greatest economic impact in poultry production. Additionally, chemotherapeutic growth promoters are being substituted for safer alternative strategies. Objective: To evaluate the effect of feeding oleoresins from chili pepper (Capsicum annuum) and turmeric (Curcuma longa L.) on the performance, survival rate, and the Productive Efficiency Index of broilers from 1 to 21d challenged by Eimeria sp. Methods: A total of 700 male 1-day-old chicks (Cobb 500) challenged with Eimeria sp, were assigned to a completely randomized design with four treatments: (1) negative control diet, without anticoccidial agent or growth promoters; (2) control diet+0.05% salinomycin; (3) negative control diet+100g/ton; and (4) negative control diet +140g/ton of test product (Curcuma longa L. plus Capsicum annuum oleoresins). Results: Body weight, weight gain, feed conversion and Productive Efficiency Index did not differ between broilers fed anticoccidial chemotherapeutics and oleoresins. In addition, there was no difference in feed intake and survival rate between dietary treatments. Conclusion: Broilers supplemented with chili pepper and turmeric oleoresins from 1 to 21d present similar body weight, weight gain, feed conversion, and Productive Efficiency Index compared to broilers supplemented with chemotherapeutic anticoccidials without affecting feed intake or survival rate.


Resumen Antecedentes: El impacto económico generado por la coccidiosis en el sector avícola es el mayor en relación con otras enfermedades. Adicionalmente, los promotores de crecimiento quimioterapéuticos se han venido reemplazando por estrategias alternativas. Objetivo: Evaluar el efecto de oleorresinas de pimiento (Capsicum annuum) y cúrcuma (Curcuma longa L.) sobre el desempeño zootécnico, tasa de supervivencia y el Índice de Eficiencia Productiva en pollos de engorde de 1 a 21 dias desafiados con Eimeria sp. Métodos: Se utilizaron 700 pollos machos (Cobb500) de 1 día de edad, distribuidos en un diseño completamente al azar con cuatro tratamientos: (1) dieta control negativo sin agentes anticoccidianos ni promotores de crecimiento; (2) dieta control+0,05% de salinomicina; (3) dieta control negativa+100g/ton; y (4) dieta control negativa +140g/ton del producto a evaluar (oleorresina de Curcuma longa L. y Capsicum annuum). Resultados: Se obtuvieron resultados similares repecto a peso corporal, ganancia de peso, conversión alimenticia e Índice de Eficiencia Productiva en los tratamientos que contenían anticoccidiano quimioterapéutico y los que contenian oleorresinas. Además, no se observaron diferencias en el consumo de alimento ni en la tasa de supervivencia entre los tratamientos dietarios. Conclusión: Los pollos de engorde suplementados entre 1 y 21 d con oleorresinas de pimiento y cúrcuma presentan similar peso corporal, ganancia de peso, conversión alimenticia e Índice de Eficiencia Productiva en comparación con los suplementados con anticoccidianos quimioterapéuticos, sin afectar el consumo de alimento ni la viabilidad.


Resumo Antecedentes: O impacto econômico da coccidiose é o maior quando comparado a outras doenças na produção avícola. Além disso, promotores de crescimento quimioterápicos tem sido substituídos por estratégias alternativas. Objetivo: Avaliar o efeito das oleoresinas da pimenta Chilli (Capsicum annuum) e açafrão-da-terra (Curcuma longa L.) no desempenho zootécnico, taxa de sobrevivência e Índice de Eficiência Produtiva de frangos de corte de 1 a 21d desafiados por Eimeria sp Métodos: Foram utilizados 700 pintos de 1d, machos (Cobb500) distribuídos em delineamento inteiramente casualizado, em quatro tratamentos: (1) dieta controle negativo, sem agente anticoccidiano ou promotores de crescimento; (2) dieta controle+0,05% de salinomicina; (3) dieta controle negativa+100g/ton; e (4)+140g/ton de produto teste (oleoresina de Curcuma longa L. mais Capsicum annuum) e desafiados por Eimeria sp. Resultados: Houve resultados similares para peso, ganho de peso, conversão alimentar e Índice de Eficiência Produtiva entre frangos alimentados com dietas contendo anticocidiano quimioterápico e dietas contendo oleoresinas. Além disso, não houve diferença para consumo de ração e a taxa de sobrevivência entre os tratamentos dietéticos. Conclusão: Frangos de corte alimentados com dietas suplementadas com oleorresinas de pimenta chili e açafrão-da-terra apresentaram resultados similares para peso, ganho de peso, conversão alimentar e Índice de Eficiência Produtiva que frangos de corte alimentados com dietas suplementadas com anticoccidianos quimioterápicos de 1 a 21d, sem afetar o consumo de ração e a taxa de sobrevivência dos animais.

20.
J Acoust Soc Am ; 147(4): 3028, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32359331

RESUMEN

This paper investigates the acoustic correlates of word initial prominence and tone in Chácobo, a southern Pano language of the northern Bolivian Amazon. This paper reports the results of a production study with five speakers producing trisyllabic words with a word final high tone. It tests a claim found in the literature that there is an additional word-initial prominence in such forms and determines its acoustic correlates compared with high tone. This study used trisyllabic forms in morphophonological contexts where these forms would appear with a final high tone. In such forms, high tone and word-initial prominence do not overlap (e.g., "panaß̞í" "asaí"). The paper takes into account five acoustic correlates across the three syllables of these words: F1, F2, F0, duration, intensity. The paper finds that the initial syllable in these words shows a statistically significant increase in intensity. There is significant speaker variation with respect to whether duration is a correlation of initial stress and the results do not provide clear evidence that initial stress is marked with duration. The final high-tone marked syllables are distinguished based on an increase in F0 and secondarily with vowel duration. Whether pitch is also a correlate of stress requires future research. The paper interprets these results as suggesting that Chácobo is a language in which tone and stress co-exist. The study thus provides instrumental evidence for a phenomenon suggested to occur in some Pano languages. The limitations of this study, including the fact the results have more than one interpretation in light of current discussions concerning stress and tone, are also discussed.


Asunto(s)
Lenguaje , Acústica del Lenguaje , Acústica , Fonética
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