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1.
Open Res Eur ; 4: 140, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39139813

RESUMEN

Observations at (sub-)millimeter wavelengths offer a complementary perspective on our Sun and other stars, offering significant insights into both the thermal and magnetic composition of their chromospheres. Despite the fundamental progress in (sub-)millimeter observations of the Sun, some important aspects require diagnostic capabilities that are not offered by existing observatories. In particular, simultaneously observations of the radiation continuum across an extended frequency range would facilitate the mapping of different layers and thus ultimately the 3D structure of the solar atmosphere. Mapping large regions on the Sun or even the whole solar disk at a very high temporal cadence would be crucial for systematically detecting and following the temporal evolution of flares, while synoptic observations, i.e., daily maps, over periods of years would provide an unprecedented view of the solar activity cycle in this wavelength regime. As our Sun is a fundamental reference for studying the atmospheres of active main sequence stars, observing the Sun and other stars with the same instrument would unlock the enormous diagnostic potential for understanding stellar activity and its impact on exoplanets. The Atacama Large Aperture Submillimeter Telescope (AtLAST), a single-dish telescope with 50m aperture proposed to be built in the Atacama desert in Chile, would be able to provide these observational capabilities. Equipped with a large number of detector elements for probing the radiation continuum across a wide frequency range, AtLAST would address a wide range of scientific topics including the thermal structure and heating of the solar chromosphere, flares and prominences, and the solar activity cycle. In this white paper, the key science cases and their technical requirements for AtLAST are discussed.


Observations of our Sun and other stars at wavelengths of around one millimeter, i.e. in the range between infrared and radio waves, present a valuable complementary perspective. Despite significant technological advancements, certain critical aspects necessitate diagnostic capabilities not offered by current observatories. The proposed Atacama Large Aperture Submillimeter Telescope (AtLAST), featuring a 50-meter aperture and slated for construction at a high altitude in Chile's Atacama desert, promises to address these observational needs. Equipped with novel detectors that would cover a wide frequency range, AtLAST could unlock a plethora of scientific studies contributing to a better understanding of our host star. Simultaneous observations over a broad frequency range at rapid succession would enable the imaging of different layers of the Sun, thus elucidating the three-dimensional thermal and magnetic structure of the solar atmosphere and providing important clues for many long-standing central questions such as how the outermost layers of the Sun are heated to very high temperatures, the nature of large-scale structures like prominences, and how flares and coronal mass ejections, i.e. enormous eruptions, are produced. The latter is of particular interest to modern society due to the potentially devastating impact on the technological infrastructure we depend on today. Another unique possibility would be to study the Sun's long-term evolution in this wavelength range, which would yield important insights into its activity cycle. Moreover, the Sun serves as a fundamental reference for other stars as, due to its proximity, it is the only star that can be investigated in such detail. The results for the Sun would therefore have direct implications for understanding other stars and their impact on exoplanets. This article outlines the key scientific objectives and technical requirements for solar observations with AtLAST.

2.
Front Psychol ; 12: 660895, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34899452

RESUMEN

The attribution of traits plays an important role as a heuristic for how we interact with others. Many psychological models of personality are analytical in that they derive a classification from reported or hypothesised behaviour. In the work presented here, we follow the opposite approach: Our personality model generates behaviour that leads an observer to attribute personality characteristics to the actor. Concretely, the model controls all relevant aspects of non-verbal behaviour such as gaze, facial expression, gesture, and posture. The model, embodied in a virtual human, affords to realistically interact with participants in real-time. Conceptually, our model focuses on the two dimensions of extra/introversion and stability/neuroticism. In the model, personality parameters influence both, the internal affective state as well as the characteristic of the behaviour execution. Importantly, the parameters of the model are based on empirical findings in the behavioural sciences. To evaluate our model, we conducted two types of studies. Firstly, passive experiments where participants rated videos showing variants of behaviour driven by different personality parameter configurations. Secondly, presential experiments where participants interacted with the virtual human, playing rounds of the Rock-Paper-Scissors game. Our results show that the model is effective in conveying the impression of the personality of a virtual character to users. Embodying the model in an artificial social agent capable of real-time interactive behaviour is the only way to move from an analytical to a generative approach to understanding personality, and we believe that this methodology raises a host of novel research questions in the field of personality theory.

3.
Drug Alcohol Depend ; 219: 108425, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33291028

RESUMEN

BACKGROUND: The prevalence of poisoning from methadone and prescription opioids is increasing in pediatric populations. Naloxone is the main antidote for treatment. Long-acting opioid toxicity may need close observation in the intensive care unit (ICU). In our previous study, naltrexone prevented re-narcotization in methadone-poisoned adults. Here, we aim to share our experience with the use of oral naltrexone for preventing recurrence of toxicity in opioid-naïve children. METHODS: In a single-center, retrospective case series, children (age ≤12 years) admitted to a poison center in Tehran (Iran) between March 2014-March 2016 were included if they presented with methadone poisoning and received naltrexone treatment in hospital. Naltrexone (1 mg/kg) was administrated orally after initial administration of 0.1 mg/kg naloxone intravenously. Children were monitored for level of consciousness, cyanosis, respiratory rate, VBG results, and O2 saturation for ≥48 h during their hospitalization. RESULTS: Eighty patients with methadone poisoning were enrolled, with median age of three years (range: 0.2-12.0). None involved polysubstance poisoning. Following naltrexone treatment, none experienced recurrent opioid toxicity during hospitalization, and hospital records indicated no readmission within 72-h post-discharge. CONCLUSION: Oral naltrexone could be a potential substitute for continuous naloxone infusion in methadone-poisoned children and reduce the need for ICU care.


Asunto(s)
Analgésicos Opioides/envenenamiento , Metadona/envenenamiento , Naltrexona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Intoxicación/tratamiento farmacológico , Adolescente , Cuidados Posteriores , Niño , Preescolar , Femenino , Hospitalización , Humanos , Lactante , Unidades de Cuidados Intensivos , Irán/epidemiología , Masculino , Naloxona , Narcóticos , Neoplasias , Alta del Paciente , Recurrencia , Estudios Retrospectivos
4.
Lasers Med Sci ; 35(5): 1007-1024, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32026164

RESUMEN

High-intensity focused ultrasound (HIFU) is widely used for skin rejuvenation and tightening. The aim of this study was to determine the safety and efficacy of HIFU for face and neck rejuvenation. A systematic search of peer reviewed articles published before December 2017 was performed using Medline, Web of Science, and Scopus databases. Retrieved studies were screened, and clinical trials or follow-up studies which were evaluated the effect of HIFU on rejuvenation treatments of face and neck area were included. Risk of bias for each study was assessed and was reported. Safety and efficacy variables, which were reported more often in papers, were included in meta-analysis. Seventeen studies involving 477 participants were included in the analysis. Meta-analysis showed moderate improvement as scores of 2.74 (95% CI 2.06-3.43) and 2.68 (95% CI 1.92-3.45), out of 5 maximum score, for objective improvement score and subjective satisfaction score, respectively. Meta-analysis of mean pain score, assessed by a 0-10 Likert score, was 4.2 (95% CI 4.27-5.19). Edema and erythema showed considerable heterogeneity, and no hyperpigmentation was reported by included studies. Included studies used multiple and different outcome variables with different scoring at various time points. Long follow-up was not reported by majority of studies. HIFU is safe procedure in short term and has a moderate effect on rejuvenation of face and neck areas.


Asunto(s)
Cara/efectos de la radiación , Ultrasonido Enfocado de Alta Intensidad de Ablación/efectos adversos , Cuello/efectos de la radiación , Rejuvenecimiento/fisiología , Adulto , Anciano , Humanos , Persona de Mediana Edad , Satisfacción Personal , Resultado del Tratamiento , Adulto Joven
5.
Environ Sci Pollut Res Int ; 26(7): 6336-6347, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30617884

RESUMEN

In the current study, the bio-adsorption potential of Callinectes sapidus biomass for control of cadmium, nickel, and lead from the aqueous stream was assessed. Spectrum analysis of FTIR, AFM, EDAX, mapping, SEM, TEM, and XRF was used to study the properties of the C. sapidus biomass. The XRF analysis revealed that C. sapidus bio-adsorbent has various effective metal oxides that can be useful to adsorb pollutants. The best model to describe the equilibrium data was Freundlich isotherm. The Langmuir bio-adsorption capacity was reported at 31.44 mg g-1, 29.23 mg g-1, and 29.15 mg g-1 for lead, cadmium, and nickel ions, respectively. Pseudo-first-order and pseudo-second-order kinetic models were studied to test the kinetic behavior of the process. An intra-particle diffusion model was used to determine the effective mechanisms involved in the bio-adsorption. Based on t1/2, it can be concluded that the equilibrium speed of the bio-adsorption process is high. The thermodynamic study showed that the metal bio-adsorption process using C. sapidus biomass is exothermic and spontaneous. The field applicability of the crab bio-adsorbent for eliminating concurrently several contaminants (metal ions, antibiotics, sulfate, nitrate, and ammonium) from an actual wastewater was successfully examined.


Asunto(s)
Braquiuros , Cadmio/aislamiento & purificación , Plomo/aislamiento & purificación , Níquel/aislamiento & purificación , Aguas Residuales/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Animales , Biomasa , Braquiuros/química , Cinética , Óxidos , Termodinámica
6.
Artículo en Inglés | MEDLINE | ID: mdl-27695865

RESUMEN

INTRODUCTION: Male pattern hair loss is widespread around the world. Its prevalence indicates the importance of finding the best treatment modalities. This study evaluates the efficacy and safety of minoxidil 5% topical foam in male pattern hair loss treatment and patient satisfaction. METHODS: This study was a before-and-after trial on 17 male patients with male pattern hair loss. Subjects were instructed to apply one capful (1 ml) of minoxidil 5% topical foam on the scalp daily for 6 months. Efficacy was assessed through hair counts, subject assessment, and global photographic review. RESULTS: Seventeen male volunteers were recruited, and three volunteers were withdrawn; 14 participated in the trial for 16 weeks, and 12 continued up to 24 weeks. The average hair count with a camera at week 16 (181.87 ± 52.42) and week 24 (194.58 ± 62.82) and with an eye count at week 16 (62.57 ± 15.28) and week 24 (69.91 ± 15.61) increased significantly compared to the baseline after intervention. CONCLUSIONS: This study confirmed that minoxidil 5% topical foam is a safe and effective treatment for MPHL. The effect of it is evident after 24 weeks of use.


Asunto(s)
Alopecia/tratamiento farmacológico , Minoxidil/uso terapéutico , Vasodilatadores/uso terapéutico , Administración Tópica , Adulto , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Resultado del Tratamiento , Adulto Joven
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