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1.
Front Physiol ; 15: 1438555, 2024.
Article in English | MEDLINE | ID: mdl-39328832

ABSTRACT

Background: The incidence of mental health issues in children is increasing worldwide. In Chile, a recent surge in reports of deteriorating mental health among school populations and an increase in complaints related to poor school climate have been observed. Physical activity, specifically active breaks in the classroom, has shown positive effects on children's health. However, evidence regarding its impact on mental health and school climate in children is limited. Objective: This work outlines the design, measurements, intervention program, and potential efficacy of the "Active Classes + School Climate and Mental Health" project. This project will assess a 12-week program of active breaks through guided videos with curricular content in the school classroom, and its effects on mental health and school climate as its primary indicators. Additionally, it will measure physical activity, physical fitness, motor competence, and academic performance in students aged 6-10 years in the Biobío province, Chile, as secondary indicators. Methodology: A multicenter randomized controlled trial involving 823 students from 1st to 4th grade (6-10 years old), six schools (three intervention and three control) will be conducted in the Biobío region, Chile. Participants belonging to the intervention group will implement video-guided active breaks through the "Active Classes" web platform, featuring curricular content, lasting 5-10 min and of moderate to vigorous intensity physical activity, twice a day, Monday to Friday, over a span of 12 weeks. Expected Results/Discussion: To our knowledge, this will be the first study in Chile to evaluate the effects of incorporating video-guided active breaks with curricular content on mental health variables and school climate in schoolchildren. Thus, this study contributes to the scarce evidence on the effects of video-guided active breaks on mental health variables and school climate in schoolchildren worldwide. Additionally, it will provide crucial information about active teaching methodologies that have the potential to positively contribute to the wellbeing of students, thus addressing the problems of mental health and climate in Chilean schools. ClinicalTrials.gov ID NCT06423404.

2.
Chemosphere ; 364: 142995, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39097114

ABSTRACT

This paper describes an alternative method for the in situ synthesis of gold nanoparticles (AuNPs) with a particle size of less than 3 nm, using nanoreactors formed by reverse micelles of 1,4-bis-(2-ethylhexyl) sulfosuccinate sodium (AOT) and nanoparticle stabilization with l-cysteine, which favor the preparation of nanoparticles with size and shape control, which are homogeneously dispersed (1% by weight) on the support of titanium dioxide nanowires (TNWs). To study the activity and selectivity of the prepared catalyst (AuNPs@TNWs), an aqueous solution of 40 mM glycerol was irradiated with a green laser (λ = 530 nm, power = 100 mW) in the presence of the catalyst and O2 as an oxidant at 22 °C for 6 h, obtaining a glycerol conversion of 86% with a selectivity towards hydroxypyruvic acid (HA) of more than 90%. From the control and reactions, we concluded that the Ti-OH groups promote the glycerol adsorption on the nanowires surface and the surface plasmon of the gold nanoparticles favors the selectivity of the reaction towards the hydroxypyruvic acid.


Subject(s)
Glycerol , Gold , Metal Nanoparticles , Nanowires , Oxidation-Reduction , Titanium , Titanium/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Nanowires/chemistry , Glycerol/chemistry , Catalysis
3.
Nanomaterials (Basel) ; 14(11)2024 May 25.
Article in English | MEDLINE | ID: mdl-38869558

ABSTRACT

Photodynamic therapy (PDT) has developed as an efficient strategy for cancer treatment. PDT involves the production of reactive oxygen species (ROS) by light irradiation after activating a photosensitizer (PS) in the presence of O2. PS-coupled nanomaterials offer additional advantages, as they can merge the effects of PDT with conventional enabling-combined photo-chemotherapeutics effects. In this work, mesoporous titania nanorods were surface-immobilized with Chlorin e6 (Ce6) conjugated through 3-(aminopropyl)-trimethoxysilane as a coupling agent. The mesoporous nanorods act as nano vehicles for doxorubicin delivery, and the Ce6 provides a visible light-responsive production of ROS to induce PDT. The nanomaterials were characterized by XRD, DRS, FTIR, TGA, N2 adsorption-desorption isotherms at 77 K, and TEM. The obtained materials were tested for their singlet oxygen and hydroxyl radical generation capacity using fluorescence assays. In vitro cell viability experiments with HeLa cells showed that the prepared materials are not cytotoxic in the dark, and that they exhibit photodynamic activity when irradiated with LED light (150 W m-2). Drug-loading experiments with doxorubicin (DOX) as a model chemotherapeutic drug showed that the nanostructures efficiently encapsulated DOX. The DOX-nanomaterial formulations show chemo-cytotoxic effects on Hela cells. Combined photo-chemotoxicity experiments show enhanced effects on HeLa cell viability, indicating that the conjugated nanorods are promising for use in combined therapy driven by LED light irradiation.

4.
Surg Neurol Int ; 15: 156, 2024.
Article in English | MEDLINE | ID: mdl-38840596

ABSTRACT

Background: Transsphenoidal surgery has become a key element in the approach to skull base pathologies. The objective of the study was to explore the morphometry of the sphenoidal region in the Peruvian population, with an emphasis on understanding its specific anatomical characteristics and providing quantitative data for the planning of transsphenoidal surgery. Methods: A cross-sectional study included a random sample of 81 cases of healthy individuals who presented to the Radiology Department of a Private Hospital Center in Peru over 1 year. Skull computed tomography scans without contrast were performed, and a detailed morphometric analysis was conducted by an expert neurosurgeon, including measurements of four parameters to evaluate the anatomy of the craniofacial region. Results: Most participants exhibited complete sellar pneumatization, followed by incomplete sellar pneumatization, while conchal pneumatization was rare. Significant differences were found between men and women in the distance from the nasal opening to the dorsum of the sella turcica. No significant gender differences were observed in other anatomical measurements or significant changes with age in anatomical measurements. Conclusion: Morphometric analysis provides crucial data for the precise customization of surgical interventions in the Peruvian population, especially in transsphenoidal surgery. The results highlight the importance of considering individual anatomical differences and gender variability during surgical planning. Morphometry emerges as a valuable tool to enhance the quality and safety of transsphenoidal surgery by adapting surgical strategies to the specific anatomical dimensions of each patient.

5.
Chemistry ; 30(50): e202400669, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-38924194

ABSTRACT

Supported metal single atom catalysis is a dynamic research area in catalysis science combining the advantages of homogeneous and heterogeneous catalysis. Understanding the interactions between metal single atoms and the support constitutes a challenge facing the development of such catalysts, since these interactions are essential in optimizing the catalytic performance. For conventional carbon supports, two types of surfaces can contribute to single atom stabilization: the basal planes and the prismatic surface; both of which can be decorated by defects and surface oxygen groups. To date, most studies on carbon-supported single atom catalysts focused on nitrogen-doped carbons, which, unlike classic carbon materials, have a fairly well-defined chemical environment. Herein we report the synthesis, characterization and modeling of rhodium single atom catalysts supported on carbon materials presenting distinct concentrations of surface oxygen groups and basal/prismatic surface area. The influence of these parameters on the speciation of the Rh species, their coordination and ultimately on their catalytic performance in hydrogenation and hydroformylation reactions is analyzed. The results obtained show that catalysis itself is an interesting tool for the fine characterization of these materials, for which the detection of small quantities of metal clusters remains a challenge, even when combining several cutting-edge analytical methods.

6.
Surg Neurol Int ; 15: 9, 2024.
Article in English | MEDLINE | ID: mdl-38344103

ABSTRACT

Background: The foramen magnum, as an anatomical structure, holds clinical and functional significance due to its strategic location in the craniovertebral transition. A detailed understanding of its dimensions and shapes is crucial for better comprehension of related pathologies and for enhancing neurosurgical techniques within a specific population. The objective is to measure precise morphometric reference points of the foramen magnum in individuals of Peruvian ancestry, aiming to establish specific anatomical patterns and potential variations within this population. Methods: The study was conducted on 17 unidentified skulls donated to the NeuroZone3D Research Center, utilizing an inelastic and soft measuring tape as the tool. Our report considered direct anthropometric measurement techniques with data collection performed by a single researcher. Results: Distinct morphometric characteristics were observed in the foramen magnum of the Peruvian population compared to other studies. The average measurements of the skull base revealed a foramen magnum with a mean length of 33.80 mm and a width of 28.70 mm, along with right condyles measuring 25 mm in length and 14.10 mm in width, and left condyles measuring 23.80 mm in length and 13.90 mm in width. Conclusion: The morphometric analysis of the foramen magnum in the Peruvian population provides valuable insights into specific anatomical features within this ethnic group. These findings could have significant implications across various medical and surgical disciplines, from interpreting diagnostic images to designing more precise therapeutic interventions tailored to this population.

7.
Molecules ; 28(17)2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37687197

ABSTRACT

The catalytic oxidation of phenethoxybenzene as a lignin model compound with a ß-O-4 bond was conducted using the Keggin-type polyoxometalate nanocatalyst (TBA)5[PMo10V2O40]. The optimization of the process's operational conditions was carried out using response surface methodology. The statistically significant variables in the process were determined using a fractional factorial design. Based on this selection, a central circumscribed composite experimental design was used to maximize the phenethoxybenzene conversion, varying temperature, reaction time, and catalyst load. The optimal conditions that maximized the phenethoxybenzene conversion were 137 °C, 3.5 h, and 200 mg of catalyst. In addition, under the optimized conditions, the Kraft lignin catalytic depolymerization was carried out to validate the effectiveness of the process. The depolymerization degree was assessed by gel permeation chromatography from which a significant decrease in the molar mass distribution Mw from 7.34 kDa to 1.97 kDa and a reduction in the polydispersity index PDI from 6 to 3 were observed. Furthermore, the successful cleavage of the ß-O-4 bond in the Kraft lignin was verified by gas chromatography-mass spectrometry analysis of the reaction products. These results offer a sustainable alternative to efficiently converting lignin into valuable products.

8.
J. Appl. Cogn. Neurosci. (Barranquilla) ; 4(2): 00424527, 2023. tab, ilus, graf
Article in English | LILACS, COLNAL | ID: biblio-1566849

ABSTRACT

This research investigates astronaut performance under simulated space conditions, using THOR, an analog astronaut training protocol, during a week-long confinement in an Analog Astronaut Training Center in Poland. Materials and Five participants, including four military and one civilian, underwent a week of isolation. Tests were conducted to assess heart rate variability ­HRV­, psychological health, and sleep patterns. Data collection and analysis were standardized, with an alpha level of p < 0.05 and power of 80%. The study found reductions in fat percentage and weight, while muscle mass and water content remained stable. HRV showed significant changes. Increased sleep and state anxiety levels were noted, along with decreased cognitive abilities. Personality traits exhibited heightened hostility and social anxiety, culminating in psychological discomfort. HRV values were normal with variations likely due to stress. A significant correlation was found between mental performance and HRV, indicating potential influence of sleep on cognitive function during isolation. The study highlights the need for more research on the psycho-logical and physiological implications of long-duration space missions and similar high-demand environments.


Esta investigación examina el rendimiento de los astronautas análogos bajo condiciones espaciales simuladas durante una semana de confina-miento en un Centro de Entrenamiento de Astronautas Análogos en Polonia. Cinco participantes, incluyendo cuatro militares y un civil, fueron sometidos a una semana de aislamiento. Se realizaron pruebas para evaluar la variabilidad de la frecuencia cardíaca ­HRV­, la salud psicológica y los patrones de sueño. La recolección y análisis de datos fueron estandarizados, con un nivel alfa de p < 0.05 y una potencia del 80%. El estudio encontró reducciones en el porcentaje de grasa y peso, mientras que la masa muscular y el contenido de agua permanecieron estables. La HRV mostró cambios significativos. Se observaron niveles elevados de sueño y ansiedad estado, junto con disminuciones en las habilidades cognitivas. Los rasgos de personalidad mostraron una hostilidad y ansiedad social aumentada, culminando en incomodidad psicológica. Los valores de HRV fueron normales con variaciones probablemente debidas al estrés. Se encontró una correlación significativa entre el rendimiento mental y la HRV, indicando la posible influencia del sueño en la función cognitiva durante el aislamiento. El estudio resalta la necesidad de más investigaciones sobre las implicaciones psicológicas y fisiológicas de las misiones espaciales de larga duración y entornos similares de alta demanda.


Subject(s)
Humans
9.
J Neurosurg Case Lessons ; 3(13)2022 Mar 28.
Article in English | MEDLINE | ID: mdl-36273859

ABSTRACT

BACKGROUND: Spontaneous intracerebral hemorrhage is a neurological condition with high rates of morbidity and mortality, which is treated by various surgical techniques that seek minimal parenchymal distortion and maximum evacuation of the hematoma. OBSERVATIONS: The advancement of technology has allowed the development of minimally invasive techniques, but the high cost of its equipment is a limitation for its practice in developing countries or third world countries. A new technique called MEP-BA by its acronym in Spanish (microscope, polypropylene endoport and Foley catheter, bipolar forceps and aspiration) is presented, which seeks optimal results with low-cost materials through a polypropylene endoport with a sterile disposable syringe and Foley catheter, allowing the creation of transcortical or transsulcal corridors for the total evacuation of the hematoma. LESSONS: The neurosurgeon must be a creator and innovator of neurosurgical techniques and equipment that allow procedures to be reproducible worldwide. The MEP-BA technique provides low-cost access through which it allows the use of aspiration and coagulation devices, minimizing brain damage and maximizing the safety and efficacy of intracerebral hematoma evacuation.

10.
Horiz. meÌud. (Impresa) ; 22(4)oct. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1421614

ABSTRACT

Las lesiones difusas de médula son raras y un reto diagnóstico. Los gliomas de bajo grado son los de mayor prevalencia y los astrocitomas primarios, el subtipo más frecuente. Presentamos el caso de un varón de 36 años, con tiempo de enfermedad de 13 años de dolor cervical insidioso, progresa con hemiparesia derecha y, posteriormente, paraparesia severa con pérdida de control de esfínteres. Mediante una RMN total de columna se evidenciaron lesiones neoproliferativas difusas abarcando todos los segmentos medulares. Se realizó una biopsia a cielo abierto en segmento T1-T2, la patología diagnosticó glioma de bajo grado. El tratamiento es controversial y se descartó la cirugía por la alta morbilidad. Se optó por radioterapia y quimioterapia por su rol importante en el control de la enfermedad.


Diffuse spinal cord injuries are rare and pose a diagnostic challenge. Low-grade gliomas are the most prevalent type, with primary astrocytomas being the most frequent subtype. We present the case of a 36-year-old man with a 13-year history of squeezing neck pain, which progressed with right hemiparesis and later with severe paraparesis and loss of sphincter control. A whole spine MRI scan showed diffuse neoproliferative lesions that spread throughout all the spinal cord segments. An open biopsy of the lesion in the T1-T2 segment was performed. The pathology report stated low-grade glioma. Treatment is controversial, so surgery was ruled out due to high morbidity. Radiotherapy and chemotherapy were chosen because they play an important role in controlling the disease.

11.
Acta med. peru ; 39(3)jul. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1419900

ABSTRACT

La craneosinostosis sagital es el cierre prematuro de la sutura sagital, ocasionando alteraciones funcionales y estructurales. El tratamiento es quirúrgico, y actualmente se cuenta con diversas técnicas, las cuales requieren de una planificación y entrenamiento para lograr óptimos resultados. Se presenta el caso de un varón de 1 año presenta crecimiento anteroposterior anormal del cráneo, indicándose tomografía cerebral sin contraste evidenciando una sinostosis sagital. Se realiza la planificación quirúrgica de la técnica a desarrollar mediante modelo 3D personalizado a escala real. Paciente cursa con buena evolución y es dado de alta. Finalmente, la tecnología de clonación 3D esencial para la educación y desarrollo neuroquirúrgico permitiendo acceder a modelos táctiles de alta precisión y bajo costo que mejoran la calidad del manejo de craneosinostosis.


Sagittal craniosynostosis is the premature closure of the sagittal suture, causing functional and structural alterations. The treatment is surgical, and there are currently various techniques, which require planning and training to achieve optimal results. We present the case of a 1-year-old male with abnormal anteroposterior growth of the skull, indicating brain tomography without contrast, showing sagittal synostosis. Surgical planning of the technique to be developed is carried out using a real-scale personalized 3D model. The patient progresses well and is discharged. Finally, essential 3D cloning technology for neurosurgical education and development allows access to high-precision, low-cost tactile models that improve the quality of craniosynostosis management.

12.
Podium (Pinar Río) ; 17(1)abr. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1448849

ABSTRACT

Los orígenes de los bailes para los pueblos tienen un alto valor, tanto por el bien que produce esta actividad física como por el significado cultural que provee. La tejida de cintas puede ser considerada como una danza ancestral o un baile producto del mestizaje e igualmente considerada como un legado que anima tanto a la Cultura Física, como a las tradiciones culturales de sus practicantes. Posiblemente es originario del pueblo Panzaleo o de otros pueblos de la sierra ecuatoriana. Sobre la base de un estudio etnográfico y la utilización de fuentes orales, fotográficas y videos, se analizaron su origen, la simbología, los cambios y persistencias de esta tradición. En tal sentido, el objetivo de la investigación es: promover el vínculo que guarda esta manifestación con la actividad física, su origen, la simbología y la vigencia de esta tradición en la parroquia de Pastocalle. El estudio es etnográfico, utilizando la técnica de la observación científica con un registro anecdótico y la entrevista con una guía de preguntas semiestructurada y el portafolio de fotos y videos. Los entrevistados no pueden precisar con exactitud la época de vigencia de la tejida de cintas, ni tampoco si este baile es originario de la parroquia, ya que también se realiza en otros pueblos cercanos. Se concluye que el vestuario original descrito es propio de la parroquia Pastocalle, que la tejida de cintas es originario del pueblo kichua Panzaleo y que actualmente está en proceso de consolidarse como referente simbólico parroquial.


As origens das danças para o povo são de grande apreço, tanto pelo bem que esta prática física produz como pelo sentido cultural que ela traz. A tecelagem de fitas pode ser considerada uma dança ancestral ou um produto da dança mestiça e igualmente um legado que anima tanto a cultura física como as tradições culturais dos seus praticantes. Pode eventualmente, vir do povo Panzaleo ou de outros povos das terras altas equatorianas. Com base num estudo etnográfico e na utilização de fontes orais, fotográficas e de vídeo, foi examinada a origem, o simbolismo, as mudanças e a persistência desta tradição. Neste sentido, o objetivo da investigação é: promover a ligação entre este evento e a atividade física, a sua origem, simbolismo e a validade desta tradição na sua Paróquia de Pastocalle. O estudo é etnográfico, utilizando a técnica da observação científica com um registo anedótico e a entrevista com um guia semiestruturado de perguntas e o portfólio de fotografias e vídeos. Os inquiridos não podem dizer exatamente quando se realizou a tecelagem das fitas, nem se esta dança teve origem na Freguesia, como também é realizada em outras aldeias próximas. Conclui-se que o traje original descrito é típico da Paróquia de Pastocalle, que a tecelagem de fitas teve origem no povo Kichua Panzaleo e que está atualmente em processo de consolidação como uma referência simbólica da Paróquia.


The origins of the dances for the people have a high value, both for the good that this physical activity produces and for the cultural significance it provides. La tejida de cintas can be considered as an ancestral dance or a dance product of miscegenation and equally considered as a legacy that animates both the Physical Culture and the cultural traditions of its practitioners. It is possibly originally from the Panzaleo people or from other towns in the Ecuadorian highlands. Based on an ethnographic study and the use of oral, photographic and video sources, its origin, symbolism, changes and persistence of this tradition were analyzed. In this sense, the objective of the research is: to promote the link between this manifestation and physical activity, its origin, symbolism and the validity of this tradition in the parish of Pastocalle. The study is ethnographic, using the technique of scientific observation with an anecdotal record and the interview with a guide of semistructured questions and the portfolio of photos and videos. The interviewees are not able to specify the exact time of validity of La tejida de cintas, nor if this dance is native to the parish, since it is also performed in other nearby towns. It is concluded that the original costume described is typical of the Pastocalle parish, that La tejida de cintas originated in the Kichua Panzaleo people and that it is currently in the process of consolidating itself as a symbolic parochial reference.

13.
Rev. Asoc. Odontol. Argent ; 110(1): 26-30, abr. 2022. ilus
Article in Spanish | LILACS | ID: biblio-1382209

ABSTRACT

Objetivo: Presentar la resolución quirúrgica de un caso clínico poco frecuente en un paciente pediátrico luego de ha- ber sufrido la herniación traumática de la Bola Adiposa de Bichat. Caso clínico: Un paciente de 3 años concurre a la guar- dia del Hospital Interzonal Especializado Materno Infantil "Don Victorio Tetamanti" de Mar del Plata, luego de haber sufrido un traumatismo que le provocó el desplazamiento par- cial de la Bola Adiposa de Bichat. Si bien este tipo de urgencias es poco frecuente, es impor- tante tener los conocimientos para un correcto diagnóstico y tratamiento (AU))


Aim: To present the surgical resolution of an infrequent clinical case in a pediatric patient who suffered traumatic herniation of Bichat's fat pad. Clinical case: A 3-year-old patient who visited the Emergency Service at the "Don Victorio Tetamanti" Hospital in Mar del Plata after suffering a trauma which caused the partial displacement of Bichat's fat pad. Although this type of emergency is quite rare, it is important to know how to per- form proper diagnosis and treatment (AU)


Subject(s)
Humans , Female , Child, Preschool , Adipose Tissue/surgery , Dental Service, Hospital , Emergencies , Hospitals, Pediatric , Argentina , Biopsy/methods , Adipose Tissue/diagnostic imaging , Oral Surgical Procedures/methods , Mouth Mucosa/injuries
14.
Article in English | MEDLINE | ID: mdl-35294686

ABSTRACT

In the present work, halloysite nanotubes modified with gold nanoparticles (AuNPs-HNT) are successfully prepared by wet chemical method for the catalytic degradation of phenothiazine dyes (azure B (AZB) and toluidine blue O (TBO)) and also cleaner reduction of 4-(4-nitrophenyl)morpholine (4NM) in the sodium borohydride (NaBH4) media. The catalyst is formulated by modifying the HNT support with a 0.964% metal loading using the HNT supports modified with 3-aminopropyl-trimethoxysilane (APTMS) coupling agent to facilitate the anchoring sites to trap the AuNPs and to prevent their agglomeration/aggregation. The AuNPs-HNT catalyst is investigated for structural and morphological characterization to get insights about the formation of the catalyst for the effective catalytic reduction of dyes and 4NM. The microscopic studies demonstrate that AuNPs (2.75 nm) are decorated on the outer surface of HNT. The as-prepared AuNPs-HNT catalyst demonstrates AZB and TBO dye degradation efficiency up to 96% in 10 and 11 min, respectively, and catalytic reduction of 4NM to 4-morpholinoaniline (MAN) is achieved up to 97% in 11 min, in the presence of NaBH4 without the formation of any by-products. The pseudo-first-order rate constant (K1) value of the AuNPs-HNT catalyst for AZB, TBO, and 4NM were calculated to be 0.0078, 0.0055, and 0.0066 s-1, respectively. Moreover, the synthesized catalyst shows an excellent reusability with stable catalytic reduction for 7 successive cycles for both the dyes and 4NM. A plausible mechanism for the catalytic dye degradation and reduction of 4NM by AuNPs-HNT catalyst is proposed as well. The obtained results clearly indicate the potential of AuNPs-HNT as an efficient catalyst for the removal of dye contaminants from the aquatic environments and cleaner reduction of 4NM to MAN, insinuating future pharmaceutical applications.

15.
Article in English | MEDLINE | ID: mdl-35206294

ABSTRACT

OBJECTIVE: To analyze the association between the behavioral profile of physical activity and sedentary time with subjective well-being and mental health in university students during the COVID-19 pandemic in Chile. METHODS: Cross-sectional study in a voluntary sample of 469 university students (22.4 ± 0.19 years; 66% women). According to students' self-reports of physical activity and sedentary time, four behavioral profiles were created to investigate their association with subjective well-being and mental health using one-factor ANOVA that was adjusted to a multifactorial model. RESULTS: The physically inactive and sedentary behavior profile presents the lowest levels of subjective well-being (p < 0.001), positive affective experiences (p < 0.001) and general mental health (p = 0.001). When adjusting for confounding variables, it was observed that the physically active and non-sedentary profile was associated with better general mental health (p < 0.01) in contrast to those who are physically active and sedentary. CONCLUSIONS: Chilean university students with a physically inactive and sedentary profile during the pandemic presented worse well-being and mental health, with a sedentary lifestyle being one of the variables that most affects the mental health of these students. Therefore, measures should be implemented to encourage this population to maintain adequate levels of physical activity and reduce sedentary times.


Subject(s)
COVID-19 , Sedentary Behavior , COVID-19/epidemiology , Chile/epidemiology , Cross-Sectional Studies , Exercise , Female , Humans , Male , Mental Health , Pandemics , SARS-CoV-2 , Students/psychology , Universities
16.
Data Brief ; 40: 107745, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35005140

ABSTRACT

About 25.7 million tons of waste tires (WT) are discarded each year worldwide causing important environmental, and health problems. This waste is difficult to manage and dispose due to its huge rate of generation and its extremely slow biodegradation. Therefore, many efforts are being made to valorise WTs into a series of marketable products under a circular economy framework. In the attempt to convert WT into higher-value products, thermochemical decomposition by pyrolysis has emerged as a promising process [1]. The pyrolysis is a thermochemical transformation (under an oxygen-depleted atmosphere) of the tire´s polymeric constituents: natural rubber (NR), styrene-butadiene rubber (SBR), and butadiene rubber (BR) into three major fractions. These fractions are a gas (10-35%, TPG) which is usually used as a heat source (50 MJ kg-1), a solid consisting mainly of recovered carbon black (12-45%, rCB), and a liquid fraction (35-65%, TPO) containing a complex mixture of organic compounds. Among the high-value compounds that can be found in the TPO are D,L-limonene, isoprene, benzene, toluene, mixed-xylene, ethylbenzene, styrene, p-cymene, and some polycyclic aromatic hydrocarbons. This mixture is commonly used as a diesel substitute and owing to its complex composition it rarely is seen as a source for more valuable products. To overcome such a complexity, and selectively produce specific chemical identities, different types of catalysts have been used [2,3]. Herein, we provide a dataset from a systematic study about catalytic pyrolysis of WT for selectively producing benzene, toluene, and xylenes (BTX) and p-cymene on noble metals (Pd, Pt, Au) supported on titanate nanotubes (NT-Ti). The comprehensive analysis of this data was recently published, thus, the analytical techniques, experimental conditions and dataset are given in the present paper as a complement to that publication [1]. The reaction was evaluated in an analytical pyrolysis unit consisting in a micropyrolizer coupled to a mass spectrometer (Py-GC/MS) operating at temperatures between 400 and 450 °C in a fast pyrolysis regime (12 s). The effectivity of catalysts was measured in terms of selectivity to monoaromatics as BTX and p-cymene, under non-catalytic and for catalytic pyrolysis conditions. Moreover, the reaction was conducted on individual rubbers (Polyisoprene, Polybutadiene, and Styrene-Butadiene) and DL-limonene, to get deep insights into the transformation behaviour and reaction pathways. Therefore, the reader will find a data-in-brief paper containing some characterizations of the WTs used for the investigation, along with a complete dataset of Py-GC/MS results. Finally, the original files for the interpretation of the MS results are also provided, so that the reader can easily use this information to further expand the study to their own interest (industrial or scientific).

18.
Rev. méd. hered ; 33(1): 51-55, ene.-mar. 2022. graf
Article in Spanish | LILACS, LIPECS | ID: biblio-1409875

ABSTRACT

RESUMEN Los aneurismas de la arteria comunicante anterior son complejos y requieren de tratamiento endovascular o microquirúrgico según sus características. El uso de enfoques mínimamente invasivos en microcirugía continúa evolucionando. Presentamos el caso de un paciente de 34 años con un aneurisma cerebral no roto de AcoA de cuello ancho, con escala de Glasgow de 15 puntos. Se realizó un abordaje supraorbitario lateral más "clipaje" total del aneurisma usando angio fluoresceína intraoperatoria. Se logró el objetivo con seguridad y eficacia; al mismo tiempo se optimizó el tiempo quirúrgico y hospitalario, maximizando la comodidad del paciente, estética y reanudación a sus actividades tempranas. (AU)


SUMMARY Anterior communicating artery aneurisms (ACAA) are complex and require endovascular or microsurgery approaches. The use of minimally invasive microsurgery techniques is evolving. We present the case of a 34-yearold patient with a broad neck, non-broken, ACAA with a Glasgow coma scale of 15 points. A lateral supra-orbitary approach with total clipping of the ACAA using intra-operatory fluorescein angiography was performed. The objective was accomplished successfully and safe, optimizing both intra-operative and hospitalization times, thus,maximizing patient comfort, esthetic and prompt return to normal duties. (AU)


Subject(s)
Humans , Male , Adult , Fluorescein , Aneurysm/surgery , Aneurysm/therapy , Microsurgery
19.
Ind Eng Chem Res ; 61(17): 6052-6056, 2022 May 04.
Article in English | MEDLINE | ID: mdl-37538052

ABSTRACT

This communication proposes a preliminary simplified kinetic model for the hydrogenation of 1-phenyl-1,2-propanedione that can render up to eight compounds, involving regioselectivity and enantioselectivity. The catalytic system comprises two functionalities; the heterogeneous catalyst (Ir/TiO2) plays the role for the hydrogenation, whereas the adsorption/binding to the active site is played by a chiral molecule (cinchonidine), added to the reaction mixture. The reaction occurs at room temperature and total pressure of 40 bar. The product distribution shows competitive parallel and series pathways with up to 12 possible reactions. Despite the complexity of both reaction and catalyst system, a simplified kinetic model was able to predict the concentrations profiles. The model assumes the reactions to be apparent first order in the concentrations of reactant and intermediate products, while the kinetic constants include all other effects (partial pressure of hydrogen, solvent and catalyst effects, and the concentration of the chiral additive). The concentration profiles were well-modeled with low residual values. The errors in the kinetic constants (k-values) were small for all relevant parameters of the main reaction pathways. Two k-values are nil, which is the lower bound imposed in the model, suggesting that these reaction pathways are likely negligible. The positive outcome from this simplified model suggests that the process can be formally treated as a first-order irreversible homogeneous catalyzed reaction, despite a heterogeneous catalyst was employed (with a modifier). Despite the promising results, the model must be extended for a more general applicability, or conditions where it is applicable.

20.
Article in English | MEDLINE | ID: mdl-34770200

ABSTRACT

OBJECTIVE: To analyze the relationship between anxiety, self-esteem, happiness index and primary school students' academic performance in Chilean adolescents from the Biobío province. METHODOLOGY: 733 (46.1% girls; 12 (1.3 years)) public primary school students that completed the 2018 Health and School Performance Survey carried out in the Biobío province were included in this cross-sectional analysis. The BECK Anxiety Inventory (BAI) was used to measure anxiety while happiness index and self-esteem were measured using the subjective happiness scale and the Rosenberg self-esteem scale, respectively. School performance was measured by grade point average (GPA) of language, math, physical education and cumulative GPA, and behavior associated with cognition in the school context was also considered. The relationship between mental health indicators and school performance was investigated using a one-way ANOVA and Pearson correlation. RESULTS: In comparison to students with low anxiety levels and high self-esteem and happiness levels, students with higher anxiety levels, lower self-esteem and happiness levels perceived themselves as having memory problems. They were also slower to solve math problems, had a shorter attention span in class and presented more difficulties in solving complex tasks, as well as being more nervous during testing. These students also got the lowest grade point average in math, language and physical education. CONCLUSIONS: High anxiety levels, low self-esteem and low happiness levels were associated with lower school performance and weaker behavior associated with cognition in Chilean adolescents. Implementing plans of emotional education and mental health could improve academic achievement.


Subject(s)
Anxiety Disorders , Happiness , Adolescent , Anxiety/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Schools , Self Concept
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