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1.
Energy Fuels ; 38(3): 2224-2234, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38323028

RESUMEN

Intensified reactors for conversion of CO2 to methanol (via hydrogenation) using metal oxide catalysts coupled with methanol conversion to aromatics in the presence of zeolites (e.g., H-ZSM-5) in a single step are investigated. Brønsted acid sites (BAS) in H-ZSM-5 are important sites in methanol aromatization reactions, and correlations of the reactivity with zeolite acid properties can guide reaction optimization. A classical way of tuning the acidity of zeolites is via the effect of the isomorphous substitution of the heteroatom in the framework. In this work, H-[Al/Ga/Fe]-ZSM-5 zeolites are synthesized with Si/T ratios = 80, 300, affecting the acid site strength as well as distribution of Brønsted and Lewis acid sites. On catalytic testing of the H-[Al/Ga/Fe]-ZSM-5/ZnO-ZrO2 samples for tandem CO2 hydrogenation and methanol conversion, the presence of weaker Brønsted acid sites improves the aromatics selectivity (CO2 to aromatics selectivity ranging from 13 to 47%); however, this effect of acid strength was not observed at low T atom content. Catalytic testing of H-[B]-ZSM-5/ZnO-ZrO2 provides no conversion of CO2 to hydrocarbons, showing that there is a minimum acid site strength needed for measurable aromatization reactivity. The H-[Fe]-ZSM-5-80/ZnO-ZrO2 catalyst shows the best catalytic activity with a CO2 conversion of ∼10% with a CO2 to aromatics selectivity of ∼51%. The catalyst is shown to provide stable activity and selectivity over more than 250 h on stream.

2.
Cureus ; 15(6): e40889, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37492836

RESUMEN

Sympathetic imbalance coupled with impairment of baroreceptor control is a key factor responsible for hemodynamic abnormalities in congestive heart failure. Vagal nerve stimulation (VNS) and baroreceptor activation therapy (BAT) are two novel interventions for the same. In this paper, we review the role of sympathovagal alterations in cardiac diseases like heart failure, arrhythmia, hypertension (HTN), etc. Studies like neural cardiac therapy for heart failure (NECTAR-HF), autonomic regulation therapy to enhance myocardial function and reduce progression of heart failure (ANTHEM-HF), and baroreflex activation therapy for heart failure (BEAT-HF), which comprise the history, efficacy, limitations, and current protocols, were extensively analyzed in contrast to one another. Vagal nerve stimulation reverses the reflex inhibition of cardiac vagal efferent activity, which is caused as a result of sympathetic overdrive during the course for heart failure. It has shown encouraging results in certain pre-clinical studies; however, there is also a possibility of serious cardiovascular adverse events if given in higher than the recommended dosage. Attenuated baroreflex sensitivity is attributed to cardiac arrhythmogenesis during heart failure. Baroreceptor activation therapy reverses this phenomenon. However, the surgical procedure for baroreceptor stimulation can have unwarranted complications, including worsening heart failure and hypertension. Considering the effectiveness of the given modalities and taking into account the inconclusive evidence of their adverse events, more clinical trials are needed for establishing the future prospects of these interventional approaches.

3.
Health Place ; 79: 102691, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34656430

RESUMEN

Long-term community resilience, which privileges a long view look at chronic issues influencing communities, has begun to draw more attention from city planners, researchers and policymakers. In Phoenix, resilience to heat is both a necessity and a way of life. In this paper, we attempt to understand how residents living in Phoenix experience and behave in an extreme heat environment. To achieve this goal, we introduced a smartphone application (ActivityLog) to study spatio-temporal dynamics of human interaction with urban environments. Compared with traditional paper activity log results we have in this study, the smartphone-based activity log has higher data quality in terms of total number of logs, response rates, accuracy, and connection with GPS and temperature sensors. The research results show that low-income residents in Phoenix mostly stay home during the summer but experience a relatively high indoor temperature due to the lack/low efficiency of air-conditioning (AC) equipment or lack of funds to run AC frequently. Middle-class residents have a better living experience in Phoenix with better mobility with automobiles and good quality of AC. The research results help us better understand user behaviors for daily log activities and how human activities interact with the urban thermal environment, informing further planning policy development. The ActivityLog smartphone application is also presented as an open-source prototype to design a similar urban climate citizen science program in the future.


Asunto(s)
Calor Extremo , Calor , Humanos , Arizona , Ciudades , Estaciones del Año
4.
J Appl Gerontol ; 42(3): 493-504, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36384346

RESUMEN

Home and community-based services (HCBS) assist people with disabilities and older adults to remain in their homes. Direct support professionals and care managers who facilitate the development of support plans need to employ person-centered approaches to ensure services are tailored to peoples' needs and preferences. The aims were to identify the key competencies needed for delivery of person-centered supports and examine the relationship between HCBS and its' outcomes in the United States. We used the competencies developed by the National Center on advancing Person-Centered Practices and Systems as a framework. We conducted a systematic review to identify the skills necessary to deliver person-centered HCBS. We coded 43 articles and identified seven competencies. Most frequently mentioned competencies related to culturally informed practice, cultivating connections, and promoting rights, choice, and control. Policy makers should create training standards for person-centered practices to ensure that people receiving HCBS live the lives they want.


Asunto(s)
Personas con Discapacidad , Servicios de Atención de Salud a Domicilio , Humanos , Estados Unidos , Anciano , Servicios de Salud Comunitaria
5.
Trop Doct ; 52(1): 192-195, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34355588

RESUMEN

Opsoclonus myoclonus syndrome secondary to scrub typhus infection is a rare clinical entity. Hence, it is important to know its clinical manifestations and complications, so that it can be properly managed. We report a 28-year-old female whose initial manifestation was only fever, which subsided in four days. Two days later, she developed opsoclonus myoclonus syndrome. This was managed with doxycycline and clonazepam, but as it persisted, intravenous immunoglobulin was added. She showed excellent response to treatment.


Asunto(s)
Meningoencefalitis , Síndrome de Opsoclonía-Mioclonía , Tifus por Ácaros , Adulto , Doxiciclina/uso terapéutico , Femenino , Fiebre/tratamiento farmacológico , Humanos , Meningoencefalitis/complicaciones , Meningoencefalitis/tratamiento farmacológico , Síndrome de Opsoclonía-Mioclonía/diagnóstico , Síndrome de Opsoclonía-Mioclonía/tratamiento farmacológico , Síndrome de Opsoclonía-Mioclonía/etiología , Tifus por Ácaros/complicaciones , Tifus por Ácaros/diagnóstico , Tifus por Ácaros/tratamiento farmacológico
7.
Neurol India ; 69(2): 493-494, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33904485

RESUMEN

A 50-year-old male, presented with a two-months history of ascending paresthesias, with continuous twitchings over the body, associated with insomnia. His electromyography (EMG) revealed neuromyotonia and was diagnosed as a case of peripheral nerve hyperexcitability (PNH) syndrome due to Leucin-rich glioma-inactivated 1 (LGI1) antibody. He showed significant improvement with intravenous immunoglobulin and carbamazepine.


Asunto(s)
Glioma , Síndrome de Isaacs , Autoanticuerpos , Fasciculación , Humanos , Inmunoglobulinas Intravenosas , Péptidos y Proteínas de Señalización Intracelular , Síndrome de Isaacs/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Músculos
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