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Copyright of International Journal of Arabic-English Studies (IJAES) is the property of International Journal of Arabic-English Studies (IJAES) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The asymptotic structure of null and spatial infinities of asymptotically flat spacetimes plays an essential role in discussing gravitational radiation, gravitational memory effect, and conserved quantities in General Relativity (GR). Bondi, Metzner and Sachs (BMS) established that the asymptotic symmetry group for asymptotically simple spacetimes is the infinite-dimensional BMS group. Given that null infinity is divided into two sets: past null infinity I− and future null infinity I+ , one can identify two independent symmetry groups: BMS− at I− and BMS+ at I+. Associated with these symmetries are the so-called BMS charges. A recent conjecture by Strominger suggests that the generators of BMS− and BMS+ and their associated charges are related via an antipodal reflection map near spatial infinity. To verify this matching, an analysis of the gravitational field near spatial infinity is required. This task is complicated due to the singular nature of spatial infinity for spacetimes with non-vanishing ADM mass. Different frameworks have been introduced in the literature to address this singularity, e.g. Friedrich's cylinder, Ashtekar-Hansen's hyperboloid and Ashtekar-Romano's asymptote at spatial infinity. This paper reviews the role of Friedrich's formulation of spatial infinity in the investigation of the matching of the spin-2 charges on Minkowski spacetime and in the full GR setting. This article is part of a discussion meeting issue 'At the interface of asymptotics, conformal methods and analysis in general relativity'. [ABSTRACT FROM AUTHOR]

For asymptotically flat spacetimes, a conjecture by Strominger states that asymptotic BMS-supertranslations and their associated charges at past null infinity I − can be related to those at future null infinity I + via an antipodal map at spatial infinity i0. We analyze the validity of this conjecture using Friedrich's formulation of spatial infinity, which gives rise to a regular initial value problem for the conformal field equations at spatial infinity. A central structure in this analysis is the cylinder at spatial infinity I representing a blow-up of the standard spatial infinity point i0 to a 2-sphere. The cylinder I touches past and future null infinities I ± at the critical sets I ± . We show that for a generic class of asymptotically Euclidean and regular initial data, BMS-supertranslation charges are not well-defined at I ± unless the initial data satisfies an extra regularity condition. We also show that given initial data that satisfy the regularity condition, BMS-supertranslation charges at I ± are fully determined by the initial data and that the relation between the charges at I − and those at I + directly follows from our regularity condition. [ABSTRACT FROM AUTHOR]

Byline: Mariem. Mohamed, Mouna. Korbi, Monia. Youssef, Adnène. Moussa, Adnène. Laatiri, Hichem. Belhadjali, Jameleddine. Zili Sir, A 69-year-old man with a medical history of diabetes mellitus and hypertension had plaque-type [...]

Byline: Mariem. Mohamed, Hichem. Belhadjali, Faten. Hammedi, Chebil. Meriem, Jameleddine. Zili Sir, Pityriasis rubra pilaris, first described by Tarral in 1835, is an erythemato-squamous disease.[sup][1] It was classified by Griffiths [...]

Penrose's idea of asymptotic flatness provides a framework for understanding the asymptotic structure of gravitational fields of isolated systems at null infinity. However, the studies of the asymptotic behaviour of fields near spatial infinity are more challenging due to the singular nature of spatial infinity in a regular point compactification for spacetimes with non-vanishing ADM mass. Two different frameworks that address this challenge are Friedrich's cylinder at spatial infinity and Ashtekar's definition of asymptotically Minkowskian spacetimes at spatial infinity that give rise to the three-dimensional asymptote at spatial infinity. Both frameworks address the singularity at spatial infinity although the link between the two approaches had not been investigated in the literature. This article aims to show the relation between Friedrich's cylinder and the asymptote as spatial infinity. To do so, we initially consider this relation for Minkowski spacetime. It can be shown that the solution to the conformal geodesic equations provides a conformal factor that links the cylinder and the asymptote. For general spacetimes satisfying Ashtekar's definition, the conformal factor cannot be determined explicitly. However, proof of the existence of this conformal factor is provided in this article. Additionally, the conditions satisfied by physical fields on the asymptote are derived systematically using the conformal constraint equations. Finally, it is shown that a solution to the conformal geodesic equations on the asymptote can be extended to a small neighbourhood of spatial infinity by making use of the stability theorem for ordinary differential equations. This solution can be used to construct a conformal Gaussian system in a neighbourhood of. [ABSTRACT FROM AUTHOR]

Eponyms are used almost daily in the clinical practice of dermatology. And yet, information about the person behind the eponyms is difficult to find. Indeed, who is? What is this person's nationality? Is this person alive or dead? How can one find the paper in which this person first described the disease? Eponyms are used to describe not only disease, but also clinical signs, surgical procedures, staining techniques, pharmacological formulations, and even pieces of equipment. In this article we present the symptoms starting with (S) and other. The symptoms and their synonyms, and those who have described this symptom or phenomenon. [ABSTRACT FROM AUTHOR]

Lichen amyloidosis is a primary localized cutaneous amyloidosis. Different types of treatment have been used without complete resolution. Herein, we report a case of patient suffering from lichen amyloidosis successfully treated with fractional ablative laser CO2. He was a 59-year-old man diagnosed lichen amyloidosis localized on the legs 10 years ago. He was treated with topical corticosteroids without any improvement. Then, we started treating the affected area with CO2 laser (limmer*) at a setting of 5-8 J/cm2 and 8 mm laser spot size. A considerable improvement was noticed after the first session. A total healing was reported after four sessions. To the best of our knowledge, only 11 reported cases of lichen amyloidosis have been successfully treated with laser CO2. However, our clinical finding seems to be one of the best reported results. [ABSTRACT FROM AUTHOR]

Lichen amyloidosis is a primary localized cutaneous amyloidosis. Different types of treatment have been used without complete resolution. Herein, we report a case of patient suffering from lichen amyloidosis successfully treated with fractional ablative laser CO 2 . He was a 59-year-old man diagnosed lichen amyloidosis localized on the legs 10 years ago. He was treated with topical corticosteroids without any improvement. Then, we started treating the affected area with CO 2 laser (limmer*) at a setting of 5-8 J/cm 2 and 8 mm laser spot size. A considerable improvement was noticed after the first session. A total healing was reported after four sessions. To the best of our knowledge, only 11 reported cases of lichen amyloidosis have been successfully treated with laser CO 2 . However, our clinical finding seems to be one of the best reported results.