Airway smooth muscle (ASM) plays an important role in asthma pathophysiology through its contractile and proliferative functions. The cyclic nucleotides adenosine 3',5'-cyclic monophosphate (cAMP) and guanosine 3',5'-cyclic monophosphate (cGMP) are second messengers capable of mediating the effects of a variety of drugs and hormones. There is a large body of evidence to support the hypothesis that cAMP is a mediator of the ASM's relaxant effects of drugs, such as beta2-adrenoceptor agonists, in human airways. Although most attention has been paid to this second messenger and the signal transduction pathways it activates, recent evidence suggests that cGMP is also an important second messenger in ASM with important relaxant and antiproliferative effects. Here, we review the regulation and function of cGMP in ASM and discuss the implications for asthma pathophysiology and therapeutics. Recent studies suggest that activators of soluble and particulate guanylyl cyclases, such as nitric oxide donors and natriuretic peptides, have both relaxant and antiproliferative effects that are mediated through cGMP-dependent and cGMP-independent pathways. Abnormalities in these pathways may contribute to asthma pathophysiology, and therapeutic manipulation may complement the effects of beta2-adrenoceptor agonists.

Mobile communication systems are always in continuous evolution due to the demands of the end-users using this technology. Therefore, before the possible launch of 5G, some technologies have opened the way to the new mobile communication system. The need for technologies that provide more comfort to users has led to the construction of complex communication systems that were only science fiction decades ago. The information society in which we are now immersed has been the result of constant progress over time. In this paper, a survey of multiple access schemes for next-generation wireless communication systems is presented. Multiple access schemes are reviewed for possible use in nextgeneration wireless communication systems such as orthogonal multiple access (OMA), non-orthogonal multiple access (NOMA), and delta-orthogonal multiple access (D-OMA), etc. General comparisons of 1G to 6G are presented. Different types of OMA are explained, and then orthogonal frequency division multiple access (OFDMA) is chosen as an example of the OMA scheme to compare with NOMA and D-OMA. There are two types of NOMA: power-domain and code-domain, which are discussed and compared. Simulation results are presented, and a comparison among different access schemes is provided.

Teachers have tried to teach their students by introducing text books along with verbal instructions in traditional education system. However, teaching and learning methods could be changed for developing Information and Communication Technology (ICT). It's time to adapt students with interactive learning system so that they can improve their learning, catching, and memorizing capabilities. It is indispensable to create high quality and realistic leaning environment for students. Visual learning can be easier to understand and deal with their learning. We developed visual learning materials (an overview of solar system) in the form of video for students of primary level using different multimedia application tools. The objective of this paper is to examine the impact of student's abilities to acquire new knowledge or skills through visual learning materials and blended leaning that is integration of visual learning materials with teacher's instructions. We visited a primary school in Dhaka city for this study and conducted teaching with three different groups of students (i) teacher taught students by traditional system on same materials and marked level of student's ability to adapt by a set of questions (ii) another group was taught with only visual learning material and assessment was done with 15 questionnaires, (iii) the third group was taught with the video of solar system combined with teacher's instructions and assessed with the same questionnaires. This integration of visual materials (solar system) with verbal instructions is a blended approach of learning. The interactive blended approach greatly promoted students ability of acquisition of knowledge and skills. Students response and perception were very positive towards the blended technique than the other two methods. This interactive blending leaning system may be an appropriate method especially for school children.

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