438 research outputs found
Shower Atomization
The research will help to design a shower for Dr. Chelson’s shelter, which can control the water flow, pressure and duration of the shower, which optimizes the utilization of water. The showers could be used in drought-hit areas where water is very scarce, as daily sanitation needs are necessary to keep a person safe and healthy without wasting water. The report from, World Health Organization shows that showers consume the most water. A timed shower could help resolve this issue through eliminating the wastage. Eco-friendly environmentalists may also be attracted to the showers, as their main purposes are to save energy and water. The showers could be set according to the needs of the person. Annually, the difference in costs reflects that these showers are effective and make optimal use of the available water and energy
Methane and carbon dioxide adsorption on edge-functionalized graphene: A comparative DFT study
With a view towards optimizing gas storage and separation in crystalline and
disordered nanoporous carbon-based materials, we use ab initio density
functional theory calculations to explore the effect of chemical
functionalization on gas binding to exposed edges within model carbon
nanostructures. We test the geometry, energetics, and charge distribution of
in-plane and out-of-plane binding of CO2 and CH4 to model zigzag graphene
nanoribbons edge-functionalized with COOH, OH, NH2, H2PO3, NO2, and CH3.
Although different choices for the exchange-correlation functional lead to a
spread of values for the binding energy, trends across the functional groups
are largely preserved for each choice, as are the final orientations of the
adsorbed gas molecules. We find binding of CO2 to exceed that of CH4 by roughly
a factor of two. However, the two gases follow very similar trends with changes
in the attached functional group, despite different molecular symmetries. Our
results indicate that the presence of NH2, H2PO3, NO2, and COOH functional
groups can significantly enhance gas binding with respect to a
hydrogen-passivated edge, making the edges potentially viable binding sites in
materials with high concentrations of edge carbons. To first order, in-plane
binding strength correlates with the larger permanent and induced dipole
moments on these groups. Implications for tailoring carbon structures for
increased gas uptake and improved CO2/CH4 selectivity are discussed.Comment: 12 pages, 7 figure
Comparison of Activation Energy and Pore Dynamics in Liquid and Gel Phases of Electroporated Lipid Bilayers using Temperature Dependent MD Simulations
Trajectory Extending Kinetic Monte Carlo Simulations to Evaluate Pure and Gas Mixture Diffusivities through a Dense Polymeric Membrane
With renewed interest in CO2 separations, carbon molecular sieving (CMS)
membrane performance evaluation requires diffusion coefficients as inputs to
have reliable estimate of the permeability. An optimal material is desired to
have both high selectivity and permeability. Gases diffusing through dense, CMS
and polymeric membranes experience extended sub-diffusive regimes which hinders
reliable extraction of diffusion coefficients from mean squared displacement
data. We improve the sampling of the diffusive landscape by implementing the
trajectory extending kinetic Monte Carlo (TEKMC) technique to efficiently
extend MD trajectories from ns to {\mu}s timescales. The obtained
self-diffusion coefficient of pure CO2 in CMS membranes derived from
6FDA/BPDA-DAM precursor polymer melt is found in agreement with previous
experimental findings. We also extend the TEKMC algorithm to evaluate the
mixture diffusivities in binary mixtures to determine the permselectivity of
CO2 in CH4 and N2 mixtures. The mixture diffusion coefficient of CO2 ranges
from 1.3-7 x 10^{-6} cm6{2}s^{-1} in binary mixture CO2:CH4 which is
significantly higher than the pure gas diffusion coefficient. Robeson plot
comparisons show that the permselectivity obtained from pure gas diffusion data
are significantly lower than that predicted using mixture diffusivity data.
Specifically in the case of the CO2:N2 mixture we find that using mixture
diffusivities led to permeslectivites lying above the Robeson limit
highlighting the importance of using mixture diffusivity data for an accurate
evaluation of the membrane performance. Combined with gas solubilities obtained
from grand-canonical Monte Carlo simulations, our work shows that simulations
with the TEKMC method can be used to reliably evaluate the performance of
materials for gas separations.Comment: Software available on https://github.com/PKMLab/tekmc Accepted on
October 25, 2023 in The Journal of Physical Chemistry
The Role of Interest in Fostering Sixth Grade Students' Identities As Competent Learners
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72489/1/0362-6784.00153.pd
Audiodescripción de referentes culturales: estudio descriptivo-comparativo y de recepción
La audiodescripción (AD) entendida como un servicio de apoyo a la comunicación con personas ciegas o con baja visión está adquiriendo cada vez más importancia profesional, social y académica. Las cifras actuales de programas que se ofrecen con AD en la televisión española, los congresos y seminarios sobre AD que se celebran en todo el mundo y el avance legislativo en materia de accesibilidad dan buena cuenta de ello. La accesibilidad reivindica su lugar en los Estudios sobre Traducción (y más concretamente, sobre Traducción Audiovisual) y aunque el interés investigador es bastante reciente, sobre todo en España, también es prolífica y ha abordado con profundidad numerosos aspectos específicos tanto del contenido conceptual como de la forma lingüística de la práctica audiodescriptora. La gran mayoría de los trabajos publicados han sido, hasta hace poco, de corte descriptivista. Y aunque indispensables, actualmente es necesario llevar a cabo estudios que corroboren o, al contrario, desestimen las conclusiones a las que se han llegado en dichos estudios descriptivos (Braun, 2008: 22-23). Los estudios de recepción están destinados a ocupar un lugar privilegiado en la investigación en Traducción Audiovisual, y muy concretamente en la investigación sobre accesibilidad, puesto que son los destinatarios de la audiodescripción o de la subtitulación para sordos, por ejemplo, los que han de expresarse y decir (e incluso exigir) cómo deberían ser los productos audiovisuales que les están dirigidos a ellos. Los estudios sobre AD alternativas, no convencionales (Fryer y Freeman, 2012 y 2013; Udo y Fels, 2009a y 2009b; Udo, Acevedo y Fels, 2010) cobran especial importancia para esta tesis, ya que se adentran directamente en la investigación de preferencias y expectativas de los usuarios, algo en lo que pretendemos dar nuestros primeros pasos. Los estudios de recepción sobre preferencias y expectativas del colectivo de personas ciegas o con baja visión son escasos en España, ya que los realizados hasta este momento se centran esencialmente en la evaluación de distintos aspectos de la comprensión o impacto emocional.
Esta tesis presenta dos estudios distintos pero complementarios que confluyen en la consecución de un único objetivo: promover la visibilidad del colectivo de personas ciegas o con baja visión, de sus necesidades y expectativas en materia de accesibilidad audiovisual. Para ello, pretendemos demostrar que la ubicación geográfica, cultural y lingüística de los agentes intervinientes en la AD, condicionan, si no determinan, el resultado de esta, entendida como proceso y como producto; y que las decisiones del descriptor se adecuan a las expectativas de sus receptores meta.
Para ello, y con carácter previo, se determinan tres objetivos preliminares que suponen la base teórica y práctica necesaria para abordar el estudio experimental que conforma el núcleo duro de la presente tesis. Perseguimos, en un primer momento, describir el panorama actual de la audiodescripción en España, revisar la literatura académica que hasta hoy se ha publicado sobre audiodescripción y establecer un perfil del receptor medio de la audiodescripción en España.
A continuación, la presente tesis se articula en dos partes fundamentales y complementarias. Cada estudio persigue un objetivo principal. Por una parte, la finalidad del estudio descriptivo es analizar y evaluar el elemento cultural presente en la audiodescripción de películas en dos lenguas y para dos audiencias meta distintas. Para ello se identifican, analizan, comparan y describen las técnicas de traducción empleadas para describir referentes culturales.
Por otra parte, el objetivo del estudio de recepción o experimental consiste en determinar si las AD que se realizan en la actualidad en España se adecuan a las preferencias y expectativas de los usuarios y, en su caso, proponer directrices o recomendaciones para la audiodescripción de referentes culturales en España
Angiogenesis: Managing the Culprits behind Tumorigenesis and Metastasis
Deregulated angiogenesis has been identified as a key contributor in a number of pathological conditions including cancer. It is a complex process, which involves highly regulated interaction of multiple signalling molecules. The pro-angiogenic signalling molecule, vascular endothelial growth factor (VEGF) and its cognate receptor 2 (VEGFR-2), which is often highly expressed in majority of human cancers, plays a central role in tumour angiogenesis. Owing to the importance of tumour vasculature in carcinogenesis, tumour blood vessels have emerged as an excellent therapeutic target. The anti-angiogenic therapies have been shown to arrest growth of solid tumours through multiple mechanisms, halting the expansion of tumour vasculature and transient normalization of tumour vasculature which help in the improvement of blood flow resulting in more uniform delivery of cytotoxic agents to the core of tumour mass. This also helps in reduction of hypoxia and interstitial pressure leading to reduced chemotherapy resistance and more uniform delivery of cytotoxic agents at the targeted site. Thus, complimentary combination of different agents that target multiple molecules in the angiogenic cascade may optimize inhibition of angiogenesis and improve clinical benefit in the cancer patients. This review provides an update on the current trend in exploitation of angiogenesis pathways as a strategy in the treatment of cancer.Ashwaq H. S. Yehya is funded by TWAS (The Academy of Sciences for the Developing
World, Italy). Chern Ein Oon is supported by L’Oréal-UNESCO for Women in Science National Fellowship
(304/CIPPM/650806/L117) and MAKNA Cancer Research Award (304/CIPPM/650859/M122)
Does the Oropharyngeal Fat Tissue Influence the Oropharyngeal Airway in Snorers? Dynamic CT Study
Sleep oscillation-specific associations with Alzheimer’s disease CSF biomarkers : novel roles for sleep spindles and tau
Background: Based on associations between sleep spindles, cognition, and sleep-dependent memory processing,
here we evaluated potential relationships between levels of CSF Aβ42, P-tau, and T-tau with sleep spindle density
and other biophysical properties of sleep spindles in a sample of cognitively normal elderly individuals.
Methods: One-night in-lab nocturnal polysomnography (NPSG) and morning to early afternoon CSF collection
were performed to measure CSF Aβ42, P-tau and T-tau. Seven days of actigraphy were collected to assess habitual
total sleep time.
Results: Spindle density during NREM stage 2 (N2) sleep was negatively correlated with CSF Aβ42, P-tau and T-tau.
From the three, CSF T-tau was the most significantly associated with spindle density, after adjusting for age, sex and
ApoE4. Spindle duration, count and fast spindle density were also negatively correlated with T-tau levels. Sleep
duration and other measures of sleep quality were not correlated with spindle characteristics and did not modify
the associations between sleep spindle characteristics and the CSF biomarkers of AD.
Conclusions: Reduced spindles during N2 sleep may represent an early dysfunction related to tau, possibly
reflecting axonal damage or altered neuronal tau secretion, rendering it a potentially novel biomarker for early
neuronal dysfunction. Given their putative role in memory consolidation and neuroplasticity, sleep spindles may
represent a mechanism by which tau impairs memory consolidation, as well as a possible target for therapeutic
interventions in cognitive decline
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