130 research outputs found
Al-Tantawi´s notebook: examples for teaching Egyptian and Arabic folklore
No full textEn este artículo se estudia el cuaderno de al-Šayj Muhammad 'Ayyād al-
Tantāwī (1810-1861) que emigró a San Petersburgo en 1840 para enseñar a los futuros
orientalistas rusos la lengua árabe en sus dos registros, el clásico y el coloquial de El Cairo;
murió en 1861 en esta ciudad rusa. El cuaderno inédito, que se conserva en la Universidad
de San Petersburgo, se publica en su integridad como anexo a este artículo. Su contenido
se clasifica en cinco categorías: 4 anécdotas lingüísticas, 4 sobre cadíes, árbitros y
gobernadores, 3 con adivinanzas lingüísticas, 2 de contenido mágico y 10 escritas por el
autor alrededor de un refrán. Se resume cada una y se resaltan sus particularidades lingüísticas
y folclóricas como parte del legado literario popular árabe. Se concluye que el cuaderno
forma parte del patrimonio cultural popular árabe y egipcio y su contenido es un material
docente de primer orden para las aulas y para el estudio de la variedad lingüística de
Egipto en el siglo XIX.This paper analyses the notebook written by hand by al-Šay j Muhammad 'Ayyād al-Tantāwī when he emigrated to Saint Petersburg in 1840 to teach classical and
dialectal Arabic to the future Russian Orientalists. He would die there in 1861. The notebook,
part of the collection held by Saint Petersburg University, is being edited and published
for the first time. It consists of a series of anecdotes that can be divided into five cat egories:
linguistic anecdotes (4), anecdotes about cadis, arbiters and governors (4), anecdotes
with linguistic riddles (3), anecdotes about magic events (2), anecdotes written by
the author about popular sayings and verses (10). The paper summarizes each anecdote
and highlights its linguistic and folkloric content as part of the Arabic literary legacy. It
concludes that the notebook forms part of Arabic and Egyptian popular cultural heritage
and contains excellent material to be taught in universities and studied by researchers who
wish to learn more about Egyptian linguistic variety in the nineteenth century
Experimental Validation of a Computational Fluid Dynamics Model of The Upper Respiratory Airways Utilizing a Heat Transfer Approach
No full textTobacco smoking is one of the leading causes of death and disease globally. E-CIGS (e-cigarettes) were introduced in 2004 and marketed as a safer alternative. However, there is growing concern that instead of displacing combustible cigarette use, E-CIGS are attracting large numbers of nicotine-naïve youth who may not have smoked otherwise. Factors such as attractive flavors, advertising targeting youth, and the introduction of nicotine salts are responsible for the rise in prevalence among youth. Unlike free-base nicotine, nicotine salts are nonvolatile and do not induce throat harshness when inhaled. One regulatory approach that has been proposed is to set a floor on the throat harshness of electronic cigarette aerosols to deter previously nicotine-naïve youth from using them. However, the relationship between throat harshness and various electronic cigarette variables, including nicotine concentration, nicotine salt fraction, electrical power, and inhalation patterns, has not been closely examined. Recently, a theoretical model was developed to quantify nicotine deposition and throat harshness from key electronic cigarette variables. This model is partly derived from a computational fluid dynamics simulation of flow through the upper respiratory airways.
This thesis aims to experimentally validate the CFD simulations used in the 1-D model derivation of the segmental heat transfer correlations. The study involved the construction of a physical model that replicates the complex geometry of the human airway used in CFD computations and measuring the temperature at various points in the model. At the same time, air was drawn through it at different flow rates (1 SLPM to 20 SLPM ). Then, temperature measurements, appropriately non-dimensionalized, were compared to the CFD-predicted temperatures at the same flow rates. An experimental setup was developed to mimic the idealized boundary conditions used in the CFD model. The setup rigorously treated measurement uncertainty and optimized temperature measurement locations in the flow path. Key measurement outcomes included temperature, relative temperature change across locations, and relative temperature change across flow rates.
Experimental results aligned with the CFD predictions after optimizing for the dominant source of uncertainty, the position of the thermocouples. This experimental set-up was deemed a working approach to validating this computational fluid dynamic simulation across the upper respiratory tract. However, to improve this setup, a more precise method is needed to locate the thermocouples inside the physical model after its construction
Does mechanical vibration optimize macro interlock in cemented arthroplasty?
No full textBackground Cemented total hip replacement has a high success rate. However, failure is still a problem, and the major reason for failure is aseptic loosening. Current surgical methods to insert prosthetic stems into a cement filled bone cavity are purely manual. Our hypothesis was that the use of vibration can improve the quality of cement interdigitation for implantation of the femoral component in cemented total hip replacement. Methods We investigated the effect that mechanical vibration during insertion has on the area of interlock of the cement with the bone, the depth of cement penetration and the required insertion force. A reusable mold was used to simulate the femoral cavity and enabled quantification of these parameters under vibrated and nonvibrated conditions. Results Our results showed that the area of interlock of cement and mold together was increased by 2.25%, and the force required to insert the stem was decreased by around 30N when the stem was vibrated at a frequency of 36 Hz and an amplitude of 2mm. Conclusion Our results indicated that vibration of the femoral stem has a beneficial effect on the cement-bone interface and that vibrating the prosthesis during insertion into the cement significantly lowers the force needed for insertion
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UNT Speaks Out
No full textThis presentation is part of the faculty lecture series UNT Speaks Out on the 2012 Presidential Primaries. In this presentation, the author gives the audience an overview of the structure of the primaries, and provides a recap of past primaries. The author also speaks about the money, momentum, and media attention in the primaries
Reactive oxygen species emissions from supra- and sub-ohm electronic cigarettes
No full textElectronic cigarettes (ECIGs) are battery-powered devices that heat and vaporize solutions containing propylene glycol (PG) and/or vegetable glycerin (VG), nicotine and possible trace flavorants to produce an inhalable aerosol. The heating process can lead to the formation of reactive oxygen species (ROS), which are linked to various oxidative damage-initiated diseases. Several studies in the literature have addressed ROS emissions in ECIG aerosols, but the effects of power, ECIG device design and liquid composition on ROS are relatively unknown. In addition, ROS emissions have not been examined in the emerging high power, sub-Ohm device (SOD) category. In this study, an acellular 2',7'-dichlorofluorescin (DCFH) probe technique was optimized to measure ROS in ECIG aerosols. The technique was deployed to measure ROS emissions in SOD and supra-Ohm ECIGs while varying power, heater coil head design and liquid composition (PG/VG ratio and nicotine concentration). Liquids were made from analytical standards of PG, VG and nicotine and contained no flavorants. At high powers, ROS emissions in ECIGs and combustible cigarettes were similar. Across device designs, ROS emissions were uncorrelated with power (R 2 = 0.261) but were highly correlated with power per unit area (R 2 = 0.78). It was noticed that an increase in the VG percentage in the liquid yielded higher ROS flux, and nicotine did not affect ROS emissions. ROS emissions are a function of device design and liquid composition at a given power. For a given liquid composition, a promising metric for predicting ROS emissions across device designs and operating conditions is power per unit area of the heating coil. Importantly, ROS formation is significant even when the ECIG liquid consists of pure analytical solutions of PG and VG; it can therefore be viewed as intrinsic to ECIG operation and not solely a by-product of particular flavorants, contaminants or additives. © The Author(s) 2018
Direct dripping: A high-temperature, high- formaldehyde emission electronic cigarette use method
No full textIntroduction: Electronic cigarettes (ECIGs) electrically heat and vaporize a liquid solution to produce an inhalable nicotine-containing aerosol. Normally the electrical heater is fed the liquid via an automatic wick system. Some ECIG users, however, elect to directly drip liquid onto an exposed heater coil, reportedly for greater vapor production and throat hit. Use of such direct drip atomizers (DDAs) may involve greater exposure to non-nicotine toxicants due to the potentially higher temperatures reached by the coil. In this study we examined nicotine and volatile aldehyde (VA) emissions from one type of DDA under various use scenarios, and measured heater temperature. Methods: Aerosols were machine-generated from an NHALER 510 Atomizer powered by an eGo-T battery (Joyetech), using a common PG-based liquid and a fixed puffing regimen. Inter-drip interval, the number of puffs drawn between replenishing the liquid on the coil, was varied from 2-4 puffs/drip. Total particulate matter, nicotine, and VA yields were quantified. Heater temperature was monitored using an infrared camera. Results: Depending on the condition, VA emissions, including formaldehyde, greatly exceeded values previously reported for conventional ECIGs and combustible cigarettes, both per puff and per unit of nicotine yield. Increasing the inter-drip interval resulted in greater VA emissions, and lower total particulate matter and nicotine yields. Maximum heater coil temperature ranged from 130°C to more than 350°C. Conclusions: Due to the higher temperatures attained, DDAs are inherently likely to produce high toxicant emissions. The diversity of ECIG use methods, including potential off-label methods, should be considered as ECIG regulatory efforts proceed. © The Author 2015
The impact of ionizing radiation compared to drug-induced immunological changes
No full textIonizing radiation (IR) activates several signaling pathways. This study shows the impact of acute low-dose IR on crucial cytokines involved in cell-mediated immunity. The immunomodulatory effects of 0.25 and 0.5 Gray (Gy) gamma rays and standard immunomodulatory drugs (Cyclophosphamide) on blood counts and significant pro-inflammatory cytokines implicated in various inflammatory conditions were tested in 20 rats. Examine the effect of acute low doses on critical cytokines, which could be utilized as an alternative to current immunosuppressive drugs. One day post-irradiation, serum levels of Interferon-gamma (INF-γ), Tumor Necrosis Factor-alpha, and Interleukin-2/ 1-beta were measured. 0.25 Gy exposure did not affect the detected cytokines or blood cell count compared to the non-irradiated group. 0.5 Gy, on the other hand, raises the majority of the immunologically examined cytokines except for INF-γ. Except for INF-γ, Cyclophosphamide reduces all of the cytokines examined. As a result, low-dose IR has a less negative influence on essential inflammatory cytokines, permitting its use. More research is needed to determine how low amounts could be used in different immunological disorders.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
VERTICAL FITTING OF GPS MEASUREMENTS
No full textThe methodological analysis of the author was motivated the fact that his team could
apply its GPS techniques directly by using an existing geoid map (GAZSÓ, TARASZOVA,
1984). Regarding the Hungarian particularities, he analysed the sensitivity of the de-
termination of elevations above sea level by applying GPS methods to the knowledge of
geoid heights. He pointed out the possibility that a 7-parameter transformation of spatial
coordinates can provide automatically a linear elevation fitting. To make a global approx-
imation to the geoid in Hungary, he derived a third-degree formula with two variables by
means of Chebyshev approximation
Mechanistic Analysis of the Pyrolysis of Vegetable Glycerin: A Reactive Force Field – Molecular Dynamics Study
No full textVegetable glycerin (VG, C3H8O3) is a triol found as an additive in food, pharmaceutical, and vaping products. Studying the pyrolysis of VG with the resulting species and their rates of formation is crucial in further understanding the underlying effects on human health. In this paper, we utilize molecular dynamics (MD) and the reactive force field (ReaxFF) to investigate VG pyrolysis. VG decomposed at a rate of activation energy Es = 204.3 kJ/mol and pre-exponential factor A0= 1.42E+14 s-1. The main products were formaldehyde (FA), acetaldehyde (Ace), propanal (PA), acrolein (Acr), and glyoxal (GA). Both MD concentration profiles and transition state searches showed that FA, followed by AA, were the favored products. VG underwent several cracking mechanisms, with the cleavage of the hydroxyl group from the middle carbon having the lowest energy barrier (ΔG‡ = 259.97 kJ/mol). Longer-chained species formed via side reactions, resulting in methacrolein, crotonaldehyde, and pentanal, along with benzene and ethylbenzene intermediates. VG decomposition was found to be endothermic where the reaction rate increased with increasing system temperature. The Ea value for decomposition and formation reactions reached a threshold at a system density of 0.13 g/mL, while the collision factor generally increased. © Engineered Science Publisher LLC 202
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