In this paper, we use concepts and results from percolation theory to investigate and characterize the effects of multi-channels on the connectivity of Dynamic Spectrum Access networks. In particular, we focus on the scenario where the secondary nodes have plenty of vacant channels to choose from-a phenomenon which we define as channel abundance. To cope with the existence of multi-channels, we use two types of rendezvous protocols: naive ones which do not guarantee a common channel and advanced ones which do. We show that, with more channel abundance, even with the use of either type of rendezvous protocol, it becomes difficult for two nodes to agree on a common channel, thereby potentially remaining invisible to each other. We model this invisibility as a Poisson thinning process and show that invisibility is even more pronounced with channel abundance. Following the disk graph model, we define and characterize connectivity of the secondary network in terms of the available number of channels, deployment densities, number of transceivers per node, and communication range. When primary users are absent, we derive the critical number of channels which maintains super-criticality of the secondary network. When primary users are present, we characterize and analyze the connectivity for all the regions: channel abundance, optimal, and channel deprivation. Our results can be used to decide on the goodness of any channel rendezvous algorithm by computing the expected resultant connectivity.
Objectives: In developing countries like Iraq, diarrhea was responsible for 70% of deaths among pediatrics. This study was designed to determine Iraqi mothers’ knowledge and malpractices associated with diarrhea management in pediatrics.Methods: A cross-sectional pilot study was done on a convenient sample of mothers in Baghdad – Iraq. Data collection was done using a validated questionnaire specifically designed for this study.Result: Most participants preferred to consult physicians or pharmacists about pediatrics diarrhea management. Breastfeeding was stopped by 19% of participants, whereas 35% of mothers who depend on formulated milk discontinued it. Only 30% of participants use oral rehydration solution therapy always as a
... Show MoreAs the child is growing up, he goes through different phases which will be accompanied by physical and psychological changes. These changes set the basis for processes of designing and making children's clothes which in turn give its required benefits and meet the physiological, psychological and community needs. That will help provide the child with healthy physical and psychological growth.
The aim of this research is to recognize the decoration of clothes by colors and drawings and its role in clothes' richness and children's education. The research limits are objective, The limits are for female (3-5) years old. The research was done in teaching kindergarten in the college of education for women in 2016. The researchers found many
Clotrimazole (CLO) is an antimycotic imidazole derivative applied locally for the treatment of vaginal yeast infections. In this study, CLO was formulated as vaginal mucoadhesive hydrogel, using different types of mucoadhesive polymers to ensure prolonged contact between active ingredient and vaginal mucosa.
Physicochemical properties of the prepared formulas were evaluated as a visual inspection, pH, swelling index, spreadability, and mucoadhesive characteristics, in addition to an in-vitro drug release. The influence of type and concentration of polymers as CMC-Na (1.5, 2.5, and 3.5%w/w), carbopol 940( 0.25, 0.5, and 1 %w/w) and poloxamer 407 (15, 25, 30%w/w) on CLO release from the prepared gels were also invest
... Show MoreThe importance of this research in studying the actor life existence on the stage through the performance art;where as all the literary theatrical dimensions didn't ignore the importance of the actor's performance.
So, it is shed a light on the nature of the scenery in the actor's performance and what its representations in the temporary directions ……..
The research set off from the imitation as a human instinct to the performance of the actor in post-modernity theater; so the researcher found that there is a question must be answered which is :Is the actor live a regression state in his theatrical performance ,or that the performance of the actor connect with collective conscience of human being which is repeated in certain
The current research dealt with the development of sciences and arts over the course of human history, and the development of sciences with their natural and human trends are important areas in developing the knowledge and application base for industrial product design and design in its various fields. Bionic science is one of the sciences that works on applying biological methods and systems found in nature to study and design engineering systems and modern technology, and for industrial products to be highly efficient, durable and resistant to natural variables in daily life for use. The transfer of technology between life forms and industrial products is desirable because the processes of development at the level of science in general
... Show MoreAlgae are photosynthetic microorganisms that play important role in aquatic ecosystems as they are the primary producers in aquatic food webs. Several groups of algae are capable of producing toxins that impact aquatic ecosystems, especially managed systems. Cyanobacteria are the most important algae in freshwaters, and many species produce cyanotoxins including hepatotoxins and neurotoxins. The potent cyano-neurotoxins β-N-methylamino-L-alanine (BMAA), 2, 4-diaminobutyric acid dihydrochloride (DABA), and anatoxin-a are especially critical with regards to public and animal health problems.
The present study aims at assessing the effects of chronic kidney disease (CKD) on thyroid hormone and leptin by evaluating the level of: leptin hormone along with thyroid hormone in CKD patients. The study has been conducted on 70 subjects, 50 patients with an age range between 20-50 years (25 males and 25 females) who were diagnosed to have CKD stage-5, and 20 normal controls whose ages ranged between 20-48 years (10 males and 10 females), who attended the Nephrology and Transplant Center in Medical City of Baghdad- Iraq from April 2018 to July 2018. The study showed a highly significant (P<0.01) increase in TSH level in CKD patients in comparison with controls. While T3 and T4 levels observed highly significant decrea
... Show MoreThis study was conducted to investigate thyroid function and Anti-Müllerian hormone (AMH) in (Chronic kidney disease) CKD patients by evaluating their levels in CKD patients, 50 patients were diagnosed to have CKD stage-5, their ages ranged between 20-50 years (25 males and 25 females) who attended the Nephrology and Transplant Center in Medical City of Baghdad- Iraq, they were recruited from April 2018 to July 2018 and were enrolled into the study. The control group consisted of 20 healthy individuals, their ages ranged between 20-48 years (10 males and 10 females). The study showed non-significant (p>0.05) increase in AMH level in CKD patients compared to the control group. On the other hand, TSH was recorded a highly significant (
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