Gamma - irradiation effect on polymethylmethacrylate (PMMA) samples has been studied using Positron Annihilation Lifetime (PAL) method. The orthopositronium (o-Ps) lifetime τ3, hence the o-ps parameters, the volume hole size (Vh) and the free volume fraction (Ꞙh) in the irradiated samples were measured as a function of gamma-irradiation dose up to 28.05 kGy. It has been shown that τ 3, Vh, and Ꞙh, are increasing in general with increasing gamma-dose, to reach a maximum percentage increment of 22.42% in τ3, 60% in Vh and 29.5% in Ꞙh, at. 2.55 kGy, whereas τ2 reaches maximum increment of 119. 7% at 7.65 kGy. The results suggest that gamma-irradiation induces structure changes in PMAM, causing degradation in the main chains, and the presence of oxygen Causes reduction in the amorphous regions ; oxygen and the peroxy radicals form cross-linking at reactive sites between neighboring chains, giving a net reduction of the degradation yield.
The aim of the research is to identify the economic and cultural role of contemporary interactive artworks from the public's point of view, with knowledge of the most important obstacles and proposals to improve the level of design and spread of interactive artworks. The descriptive approach was used, and the researcher used a questionnaire tool that was distributed to the audience for the events of Noor Al Riyadh (2021) and the size of the participating sample was (194) individuals from all spectrums of society. It was found through the results of the existence of public approval of the economic role of contemporary interactive artworks, as they contribute to supporting the national economy. It attracts the public to attend various paid
... Show Morehe study aims to build a model that revolves around the main question of the role of strategic agility (SA) in enhancing organizational excellence (OE). For the purpose of achieving OE and to determine the extent of interest and knowledge of managers at the Midwest Refineries Company (MRC) on the theoretical and practical implications, and on the performance foundations of these two vital variables with the aim of continuous improvement. A questionnaire was used and distributed to a random sample of 54 managers in this important energy production company. The study followed the descriptive analytical approach to answer the questions raised. The study model and dimensions were built according to reference models, most notably the models (Al-
... Show MoreRapid and continuous developments and changes in the modern business environment in all areas of economic, environmental, social, technology and communications push economic units to search for modern methods and methodologies to produce products at low cost as well as produce products that meet the wishes of customers in terms of quality and environment to maintain their market position, and accounting for the costs of the flow of materials is one of the most prominent environmental management accounting techniques capable of providing information to help produce
This study deals with an important area in the field of linguistics, namely person deixis.
The study aims at: (1) Describing the notion of deixis, its importance, and its place in the field
of linguistics, (2) Presenting a detailed illustration of person deixis, and (3) Conducting an
analysis of person deixis in one of Synge‟s plays Riders to The Sea according to Levinson‟s
model. The most important aim of these three is the third one (the analysis). To achieve this
aim, the researcher depends on Levinson‟s (1983) descriptive approach. According to the
descriptive approach of deixis, the category of person deixis can be defined as the encoding of
the participant roles in the speech situation. This encoding is r
Keloids are prevalent fibro-proliferative tumors, and treating them is still a challenge although intralesional injections of triamcinolone acetonide (TAC) are effective, they have frequently linked adverse effects. Pentoxifylline (PTX) is an anti-fibrotic and anti-inflammatory, and vasodilator. It has not yet been tested for intralesional injection in keloids. The aim of the study is to study the efficacy of intralesional pentoxifylline versus triamcinolone acetonide in keloid scars of 40 patients. In this study, 40 patients with keloid scars regardless of the cause of keloid born, 20 patients have injected with intralesional triamcinolone acetonide, and 20 patients with intralesional pentoxifylline every two weeks until the lesi
... Show MoreSoftware cost management is a significant feature of project management. As such, it needs to be employed in a project or line of work. Software cost management is integral to software development failures, which, in turn, cause software failure. Thus, it is imperative that software development professionals develop their cost management skills to deliver successful software projects. The aim of this study is to examine the impact of cost management success factors with project management factors and three agile methodologies – Extreme Programming (XP), Scrum and Kanban methodologies which are used in the Pakistani software industry. To determine the results, the researchers applied quantitative approach through an extensive survey on
... Show MoreAsthma is a chronic in?ammatory respiratory disease associated with the changes of asthmatic airway structural that result from interact remodeling and in?ammatory processes lead to obstruction of airway. Guggulsterone (GS) is a bioactive compound and plant steroid present in guggul gum of Commiphora wightii, which has anti-inflammatory and antioxidant activities. This study designed to investigate of anti-inflammatory activity of gugglsterone in improvement of asthma. Forty eight healthy albino male rats divided to six groups, Group I: Control group (distal water), Group II: Positive control group (distal water) with sensitization, Group III: Guggulsterone (25 mg/kg/day) with sens
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