352 research outputs found
Ameroseius aegypticus El-Badry, Nasr & Hafez 1979
No full text<i>Ameroseius aegypticus</i> El-Badry, Nasr & Hafez, 1979 <p> <i>Ameroseius aegypticus</i> El-Badry, Nasr & Hafez, 1979: 2.</p> <p> <i>Ameroseius aegypticus</i>. — Zaher 1986: 401; Narita <i>et al.</i> 2015: 395; Mašán 2017: 26.</p> <p> <b>Distribution and habitats – Egypt</b>, from decayed debris under wild-sage (<i>Lantana camara</i> L.) (Lamiales: Verbenaceae), water weeds and barley grain (El-Badry <i>et al.</i> 1979; Nasr <i>et al.</i> 2011; ElSayed Gad <i>et al.</i> 2020).</p> <p> <b>Published material from Iran – Chaharmahal va</b> <b>Bakhtiari Province</b>, Shahrekord, Saman, Farokhshahr, Boldaji and Choghakhor, from soil and decaying wood; <b>Esfahan Province</b>, Esfahan, from soil; <b>Guilan Province</b>, from stored rice, rice dust and debris (Roodbar), soil in olive orchards, (Sangar), rice hulls,; Sangar, Eslamabad (Shaqaji) Village, from woodchips, from soil, stored products, debris, plant foliage, leaves, wood, and manure; <b>Kerman Province</b>, Kerman, from cow manure and sheep manure; <b>Khorasan</b> <b>Razavi Province</b>, Kashmar, from soil of vineyards; <b>Khuzestan Province</b>, Izeh, from soil; <b>Mazandaran Province</b>, in honey bee hives; <b>Khuzestan and Golestan</b> <b>Provinces</b>, from soil, debris, soil of ants nests and fungi (Kazemi and Rajaei 2013; Nemati <i>et al.</i> 2018).</p> <p> <b>Note –</b> In all above refreences, this species has been reported as <i>Sertitympanum aegypticus</i>.</p>Published as part of <i>Khalili-Moghadam, Arsalan & Saboori, Alireza, 2021, World distribution and habitat scope of Ameroseiidae (Acari: Mesostigmata), pp. 403-450 in Persian Journal of Acarology 10 (4)</i> on page 406, DOI: 10.22073/pja.v10i4.67440, <a href="http://zenodo.org/record/7173383">http://zenodo.org/record/7173383</a>
The binding and activation of the glucagon-like peptide-1 receptor by exendin-4
No full textBackground and purpose
Exendin-4 (EX4) has the same physiological properties as glucagon-like peptide-1 (7-36)amide (GLP-1). EX4 has 50% identity with GLP-1, with an extra nine amino acids at its C-terminus. The two peptides mediate their functions through coupling to the glucagon like peptide-1 receptor (GLP-1R) with similar affinity and potency. Unlike N-terminally truncated GLP-1, (GLP-1(15-36)amide), the equivalently truncated EX4(9-39) binds GLP-1R without significant loss of affinity; furthermore, GLP-1(15-36) is a partial agonist while EX4(9-39) is an antagonist. Previous binding analysis of either N or C-terminally truncated EX4 at rGLP-1R suggested that the residues responsible for its extra affinity are at its C-terminus, EX4 residues 31-39. Crystal structures supported by mutagenesis showed similar interactions of both GLP-1 and EX4 at the isolated N-terminal domain of human GLP-1R (hGLP-1R-NTD) apart from a subtle hydrogen bond between Ser32 in EX4 and Glu68 in hGLP-1R-NTD.
Experimental approach
The affinities and activities of GLP-1, EX4 and various analogues were measured at human and rat GLP-1R (hGLP-1R and rGLP-1R, respectively) and various receptor variants. Computer models, molecular dynamics coupled with in silico mutagenesis, were used to model and interpret the data.
Key results
The membrane-tethered NTDs of hGLP-1R displayed similar affinity for GLP-1 and EX4 in contrast to previous studies using the soluble isolated domain. The selective high affinity at rGLP-1R and the rGLP-1R-like mutant hGLP-1R-Glu68Asp for EX4(9–39) over EX4(9–30) was due to Ser32 in the ligand. This selectivity was not observed with hGLP-1R and the hGLP-1R-like mutant rGLP-1R-Asp68Glu. Gly16-EX4(9–30) was an agonist for rGLP-1R and hGLP-1R-Glu68Asp but was an antagonist for hGLP-1R and rGLP-1R-Asp68Glu. Glu22-GLP-1(15-36) was a partial agonist for all tested receptors. Insertion of (EEEAVRL) of EX4 instead of their equivalent sequence in GLP-1(15-36) prevented its activity and did not enhance its affinity. Substitution of Ser32 in EX4 by similar hydrogen bond donor amino acids did not enhance EX4 affinity or potency.
Conclusions and implications
GLP-1 and EX4 bind to the NTD of hGLP-1R with similar affinity. A hydrogen bond between Ser32 of EX4 and Asp68 of rGLP-1R is responsible for the improved affinity of EX4 and can play a role in the antagonist/agonist switch of Gly16-EX4(9–30) at the rat receptor. The discovery of the novel antagonist/agonist switch suggests a new mechanism of activation by GLP-1 which does not require its extreme N-terminal residues
Sensor cromo-fluorógeno selectivo para la detección de Cu2 + en solución acuosa
No full text[EN] A simple chemosensor consisted of an Imidazole derivative (N,N-dimethyl-4-(4,5-di(thiophen-2-yl)-1H-imidazol-2-yl)benzenamine) was synthesized and characterized. The chemosensor 1 showed a selective colorimetric sensing ability for Cu2+ by changing colour from pale yellow to red in aqueous solutions facilitating naked eye detection of Cu2+. The UV/Vis titration in aqueous solutions (MeCN: H2O, 1:1 (v/v), pH 7.4) showed high sensitivity towards Cu2+ with a limit of detection of 4.4 μM which is lower than WHO acceptable limits (31.5 μM) in drinking water. Additionally, the fluorescence of chemosensor 1 in MeCN : H2O 1:1 (v/v) solutions (1.0 × 10-5 mol dm-3) at pH 7.4 is quenched in the presence of Cu2+.[ES] Un quimiosensor simple consistente en un derivado de imidazol (N, N-dimetil-4- (4,5-di (tiofen-2-il) -1H-imidazol-2-il) bencenamina) fue sintetizado y caracterizado. Este quimiosensor mostró una capacidad de detección colorimétrica selectiva para Cu2 + cambiando el color de amarillo pálido a rojo en soluciones acuosas que facilitan la detección de Cu2 + a simple vista. La valoración UV / Vis en soluciones acuosas (MeCN: H2O, 1: 1 (v / v), pH 7,4) mostró una alta sensibilidad hacia Cu2 + con un límite de detección de 4,4 μM que es inferior a los límites aceptados por la OMS (31,5 μM) para agua potable. Además, la fluorescencia de este quimiosensor en soluciones de MeCN: H _ {2} O 1: 1 (v / v) (1,0 x 10-5 mol dm - 3) a pH 7,4 se extingue en presencia de Cu2 +.Essam Elsayed Mohamed Okda, H. (2017). Sensor cromo-fluorógeno selectivo para la detección de Cu2 + en solución acuosa. Universitat Politècnica de València. https://riunet.upv.es/handle/10251/78183TFG
Correction: Guidelines for the prevention, detection and management of the renal complications of COVID-19 in Africa
No full textThe authors of the article ‘Guidelines for the prevention, detection and management of the renal complications of COVID-19 in Africa’ [1] wish to acknowledge the contribution of Professor Hussein El Fishawy. Our guidelines drew on various sources, including the Egyptian Ministry of Health guidelines, portions of which were adapted and reproduced with permission from the Egyptian Ministry of Health. Two of the authors of those guidelines, Professors Elsayed and Zaki, are also coauthors of our paper. Professor El Fishawy was the third author of the Egyptian guidelines and we would like to acknowledge his contribution to our review through this source, especially with respect to the treatment algorithms for patients with kidney transplants and those with acute kidney injury. Reference1. Elsayed HM, Wadee S, Zaki MS, Were AJO, Ashuntantang GE, Bamgboye EL, et al. Guidelines for the prevention, detection and management of the renal complications of COVID-19 in Africa. Afr J Nephrol. 2020; 23(1):109-126
Représentations littéraires du sacré dans le roman maghrébin de langue française
No full textThis interdisciplinary study explores how Driss Chraïbi’s L’Homme du Livre (1995), Assia Djebar’s Loin de Médine (1991), and Anissa Boumediène’s La fin d’un monde (1991) present accounts of particular historical moments in early Islam. This study explores the role of the imagination as well as freedom of invention when reconstructing historical events. It engages the novels through a study of the interplay between the literary text and the sources and traditions that impact and shape the text narrative. Gaining direct access to the original sources in Arabic serves to analyze how religious and early historical materials are considered in and reflected by the fictional texts. Because the sources tend to differ in both content and approach, this study examines their preoccupations in order to determine the criteria of selection applied by each novelist.Ph.D.Includes bibliographical referencesIncludes vitaby Hanan Elsaye
Intrathecal Drug Delivery Systems Survey: Trends in Utilization in Pain Practice [Corrigendum]
No full textAbd-Sayed A, Fiala K, Weisbein J, et al. J Pain Res. 2022;15:1305–1314.
The authors have advised there is an error in the author list on page 1305. The author name “Alaa Abd-Sayed” should read “Alaa Abd-Elsayed”.
The authors apologize for this error
A Visual Preference Study of Urban Outdoor Spaces in Egypt.
No full textThe large population increase in Egypt's major urban centers, especially Cairo, has caused a critical housing shortage. Large, newly-planned communities such as Madinat Nasr, Al Mukataum, and El Maadi have been developed at a very fast pace in the desert surrounding the city of Cairo. Planners' eagerness for quick community development has led to little consideration being given to the characteristics of natural environment or to the preferences of potential residents. This dissertation was particularly concerned with the study of people's visual preferences and their experiences of urban outdoor spaces in Egypt. The research was designed to measure the visual preferences of 150 Madinat Nasr residents for different kinds of outdoor environments in the neighborhood. A photo-questionnaire was used to gather data about these preferences. Results indicated that both the designer and the public categorized the urban environment into relatively similar dimensions. Important differences were observed, however, in the separation of the residential spatial environment scenes into two separate groups, one containing shade tress and the other devoid of vegetation. This indicated that people were highly sensitive to the role of shade trees in residential areas. People also regrouped scenes of open spaces on the basis of activities (active or passive recreations) taking place in each scene, rather than on the basis of their visual similarity. The overall experience of the outdoor urban environment was shown to be influenced by several components, such as "function of the space", "natural elements", and "space definition". The study results further indicated that the photo-questionnaire method was both reliable and valid for use in Egypt and would provide a research population the change to participate in the shaping of their environment. Design criteria and recommendations proposed were directly derived from the study findings of people's preferences and needs. Design criteria were recommended for use by both local and foreign designers of new urban developments in Egypt and in similar environments.PhDUrban planningUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/159831/1/8402376.pd
The influence of biomodal and spatially co-incidental sensory information on the performance of unimanual and bimanual skills in children with and without celebral palsy
No full textThe present thesis consisted of four studies to investigate the influence of using bimodal stimuli on aiming, unimanual and bimanual prehesion skills in children. Employing auditory and visual stimuli that are spatially and temporally co-incidental shown within the present studies provides bimodal stimuli that were known so far for enhancing sensory information. Reach to touch, and reach to grasp were examined in fourteen children with cerebral palsy (CP) and eleven of their typically developing peers (TD). 3D kinematic analyses was used to capture the aiming movement of participants while they were presented with either auditory (pure-tone sound/broadband sound), visual (light only) for '"! 'h~'" ~')I' unimodal conditions, or as a combined visual -auditory stimulus for bimodal conditions in a randomised order. Unimanual and bimanual prehension (congruent vs. incongruent) were also investigated. The data revealed group differences in the integration of bimodal stimuli that were characterised by reduction in participant reaction time for the TD children but not the CP children. Unimanual and bimanual reaching and grasping skills were influenced in both groups as shown from velocity profiles, kinematic landmarks and inter limb coupling. Results showed that enhancing the environment with sound and light resulted in more controlled and coordinated movements for both groups of children.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Degradation modeling of ink fading and diffusion of printed images
No full textColor printing plays an important role in the modern society. It is known that the color of printed images degrades gradually due to the fading and diffusion of the inks. Color degradation leads to a distortion or loss of the original information in printed images. Therefore, it is desirable to understand how the color of printed images changes over time. In this dissertation, we present degradation models to predict the characteristics of the ink fading and diffusion of printed images.
We begin by modeling the ink degradation from a physics-based perspective. Color images are printed by projecting small ink dots on medium, usually paper. This technique is called halftone printing. Halftone printing of color images results in a variety of ink mixtures and subsequently their potential catalytic fading. For the most commonly used Cyan-Magenta-Yellow-Black (CMYK) ink set, sixteen possible ink mixtures are generated during printing. A state transition diagram is then proposed for the ink fading in this multi-ink printing scenario. The ink area coverage is used as the performance indicator. Assuming constant fading and diffusion rates, we develop an ink fading model based on the differential equations according to the state transition diagram and an autoregressive ink diffusion model by discretizing the two-dimensional diffusion equation. The two models are then integrated into a single degradation model.
Further examination of the developed degradation models reveals that the fading or diffusion rate is equivalent to the hazard rate in reliability engineering. It is known that the hazard rate of the exponential failure time distribution is constant. Hence, the developed degradation model with constant fading and diffusion rates is equivalent to the multistate Markov process model with exponential transition time distribution. By using non-exponential transition time distributions, the fading and diffusion rates become time-varying and a more general semi-Markov process degradation model is developed accordingly.
Moreover, stochastic process models are investigated to provide stochastic area coverage prediction for the ink degradation. We first model the ink fading using the Hull-White/Vasicek (HWV) stochastic process. The HWV ink fading model considers that the variance of the ink area coverage shrinks as it approaches zero. Besides, spatial convolution is used to model ink diffusion. The two models are integrated into a spatio-temporal stochastic degradation model for the ink fading and diffusion of printed images. The cases of recurrent and non-recurrent time-varying fading and diffusion rates are investigated.
Inks on the paper degrade, so does the paper. The degradation of paper condition may in turn affect the degradation of the inks. Therefore, the investigation of the degradation modeling of ink fading and ink diffusion with ink-paper interactions is needed. Two aspects of the ink-paper interactions are considered, i.e., the effect of paper aging such as depolymerization and yellowing, and the fiber orientation of the paper.
The degradation process of printed images usually takes a very long time. An accelerated degradation model and the optimal design of accelerated degradation test planning is developed for accurate degradation prediction of printed images. The effects of three constant environmental stresses: temperature, humidity, and illumination (intensity), are investigated, and experimental data are used to validate the proposed model. The results show strong agreements between the proposed ink fading and ink diffusion prediction model and the actual experimental data.Ph.D.Includes bibliographical reference
Different Acid Systems Interactions with Sand and Ceramic Proppants Used in Gravel-Packed and Fractured Wells
No full textProppants are solid particles, extensively used in hydraulic fracturing operations. These materials possess specific mechanical strength indispensable in keeping induced fractures open, resulting in up-surged well production.
Proppants have different parameters including density, mechanical strength, internal porosity, shape, sieve distribution, and most importantly acid resistance.
The acid resistance of the fracturing proppants, defined as the stability and suitability of proppants when they come into contact with different acids, is an important property. Numerous acids are used during the hydraulic fracturing process to remove the scale and clays affecting the fracture conductivity. Inopportunely, these acids adversely affect the proppants already existing in the fracture. The industry measures the acid solubility of proppants according to the API RP 19C/ISO 13503-2 standard. However, it fails to give any guidance on the anticipated final effect of acid dissolution on the mechanical performance of the tested proppants.
This study investigates different factors affecting the interactions of different acid systems with sand and ceramic proppants under downhole conditions. Solubility experiments were conducted using translucent and aging cells at temperatures up to 350°F. The effects of varying acid system, temperature, soaking time, static, and dynamic conditions were examined. The supernatant of solubility tests was analyzed with Fluorine Nuclear Magnetic Resonance (19F-NMR) to identify the reaction products. Total key cations’ concentrations were measured using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Proppants were then analyzed by X-ray fluorescence (XRF) and X-ray diffraction (XRD) to detect their mineral composition. After performing solubility tests, the residual solids were then dried and analyzed using Scanning Electron Microscopes (SEMs) with Energy Dispersive X-ray Spectroscopy (EDS) capabilities. Moreover, the effects of acid dissolution on the mechanical performance of proppants were also tested using an automated load frame.
Experimental results show that monocrystalline sand proppants are soluble in regular mud acid (12.0 wt% HCl, 3.0 wt% HF), with a maximum recorded solubility of 10.0 wt%. Clay-based ceramic proppants are also soluble in mud acid, with much higher acid solubility compared to sand proppants. Proppant pack shows more compaction for clay-based proppants than that of sand proppants prior to and after acid exposure. Bauxitic ceramic proppants have a minimal solubility of 0.5 wt% in 10.0 wt% HCl. The proppant, however, is readily soluble in different mud acid solutions, reaching up to 56.0 wt% dissolution in some extreme cases. The higher solubility of ceramic proppants is attributed to HF attack at the grain boundaries.
Understanding the effects of various acids on natural and synthetic proppants will improve production capabilities by promoting the design of acidizing regimens recommended during hydraulic fracturing operations
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