Public Evaluation Of Historical Building Facades In The Vicinity Of Dataran Merdeka, Kuala Lumpur

Historical district is an important element of city image content. Among the visual elements of a historical district, the building façade is an important element in representing the architectural features. Building façade is mostly the matter of evaluation to portray the visual characteristics of an environment. Therefore, giving attention and imposing sensitivity to the evaluation of building facades in a historical district directly influence the historical images. A historical area adjacent to Dataran Merdeka, located in Kuala Lumpur city, was chosen as the study area. The issue is focussed on the lack of harmony among the shapes, colours, decorations, and architectural styles of the historical building facades which have influenced the historical images in the study area. This inconsistency is in contrast with the Kuala Lumpur Structure Plan 2020 visions, which emphasizes on creating strong images for all the districts in Kuala Lumpur city. Thus, to deal with the stated issue, the main objective of the study was to investigate the building facades which represented the historical images of the study area based on the public‘s evaluation. The second objective was to investigate the architectural elements and characteristics which influence the public’s evaluation of the historical images of the building facades in the study area. The third objective was to identify the visual elements which influence the historical images of the building facades in the study area based on the public’s evaluation. Finally, the research tried to explore the urban elements which influence the historical images of the building facades in the study area based on the public’s evaluation. A quantitative method was used to achieve the objectives of the study. In this line, a questionnaire-based survey was chosen as a data collection instrument. The research participants chosen were visitors who are familiar with the area, and willing to answer the questions. Data analysis was carried out using both the content analysis and inferential analysis. The results suggested that the facades, with the highest mean scores, were considered as strongly representing the historical images and these include harmonious arches, columns, pilasters, ornament, and bright-coloured materials. Cleanliness, the use of appropriately architectural details, legibility, coherence, and the harmonious repetition of the elements were identified as the other factors which also improved the historical images of the facades. Moreover, the results also denoted the architectural style, colour, shape and material of the facades as the architectural elements, and the harmony between historical and modern buildings and street furniture as urban elements which influenced the evaluations of the historical building façade images. The findings of the study assist urban designers and planners to consider the importance of people’s evaluation of historical building facades

Progesterone modulation of transmembrane helix-helix interactions between the α-subunit of Na/K-ATPase and phospholipid N-methyltransferase in the oocyte plasma membrane

<p>Abstract</p> <p>Background</p> <p>Progesterone binding to the surface of the amphibian oocyte initiates the meiotic divisions. Our previous studies with <it>Rana pipiens </it>oocytes indicate that progesterone binds to a plasma membrane site within the external loop between the M1 and M2 helices of the α-subunit of Na/K-ATPase, triggering a cascade of lipid second messengers and the release of the block at meiotic prophase. We have characterized this site, using a low affinity ouabain binding isoform of the α1-subunit.</p> <p>Results</p> <p>Preparations of isolated plasma membranes from <it>Rana </it>oocytes demonstrate that physiological levels of progesterone (or the non-metabolizable progestin R5020) successively activate phosphatidylethanolamine-N-methyltransferase (PE-NMT) and sphingomyelin synthase within seconds. Inhibition of PE-NMT blocks the progesterone induction of meiosis in intact oocytes, whereas its initial product, phosphatidylmonomethylethanolamine (PME), can itself initiate meiosis in the presence of the inhibitor. Published X-ray crystallographic data on Na/K-ATPase, computer-generated 3D projections, heptad repeat analysis and hydrophobic cluster analysis of the transmembrane helices predict that hydrophobic residues L, V, V, I, F and Y of helix M2 of the α1-subunit interact with F, L, G, L, L and F, respectively, of helix M3 of PE-NMT.</p> <p>Conclusion</p> <p>We propose that progesterone binding to the first external loop of the α1-subunit facilitates specific helix-helix interactions between integral membrane proteins to up-regulate PE-NMT, and, that successive interactions between two or more integral plasma membrane proteins induce the signaling cascades which result in completion of the meiotic divisions.</p

Ouabain Interaction with Cardiac Na+/K+-ATPase Initiates Signal Cascades Independent of Changes in Intracellular Na+ and Ca2+

We have shown previously that partial inhibition of the cardiac myocyte Na+/K+-ATPase activates signal pathways that regulate myocyte growth and growth-related genes and that increases in intracellular Ca2+ concentration ([Ca2+]i) and reactive oxygen species (ROS) are two essential second messengers within these pathways. The aim of this work was to explore the relation between [Ca2+]i and ROS. When myocytes were in a Ca2+-free medium, ouabain caused no change in [Ca2+]i, but it increased ROS as it did when the cells were in a Ca2+-containing medium. Ouabain-induced increase in ROS also occurred under conditions where there was little or no change in [Na+]i. Exposure of myocytes in Ca2+-free medium to monensin did not increase ROS. Increase in protein tyrosine phosphorylation, an early event induced by ouabain, was also independent of changes in [Ca2+]i and [Na+]i. Ouabain-induced generation of ROS in myocytes was antagonized by genistein, a dominant negative Ras, and myxothiazol/diphenyleneiodonium, indicating a mitochondrial origin for the Ras-dependent ROS generation. These findings, along with our previous data, indicate that increases in [Ca2+]i and ROS in cardiac myocytes are induced by two parallel pathways initiated at the plasma membrane: One being the ouabain-altered transient interactions of a fraction of the Na+/K+-ATPase with neighboring proteins (Src, growth factor receptors, adaptor proteins, and Ras) leading to ROS generation, and the other, inhibition of the transport function of another fraction of the Na+/K+-ATPase leading to rise in [Ca2+]i. Evidently, the gene regulatory effects of ouabain in cardiac myocytes require the downstream collaborations of ROS and [Ca2+]i

Intracellular Reactive Oxygen Species Mediate the Linkage of Na+/K+-ATPase to Hypertrophy and its Marker Genes in Cardiac Myocytes

We showed before that in cardiac myocytes partial inhibition of Na+/K+-ATPase by nontoxic concentrations of ouabain causes hypertrophy and transcriptional regulations of growth-related marker genes through multiple Ca2+-dependent signal pathways many of which involve Ras and p42/44 mitogen-activated protein kinases. The aim of this work was to explore the roles of intracellular reactive oxygen species (ROS) in these ouabain-initiated pathways. Ouabain caused a rapid generation of ROS within the myocytes that was prevented by preexposure of cells to N-acetylcysteine (NAC) or vitamin E. These antioxidants also blocked or attenuated the following actions of ouabain: inductions of the genes of skeletal α-actin and atrial natriuretic factor, repression of the gene of the α3-subunit of Na+/K+-ATPase, activation of mitogen-activated protein kinases, activation of Ras-dependent protein synthesis, and activation of transcription factor NF-κB. Induction of c-fos and activation of AP-1 by ouabain were not sensitive to NAC. Ouabain-induced inhibition of active Rb+ uptake through Na+/K+-ATPase and the resulting rise in intracellular Ca2+ were also not prevented by NAC. A phorbol ester that also causes myocyte hypertrophy did not increase ROS generation, and its effects on marker genes and protein synthesis were not affected by NAC. We conclude the following: (a) ROS are essential second messengers within some but not all signal pathways that are activated by the effect of ouabain on Na+/K+-ATPase; (b) the ROS-dependent pathways are involved in ouabain-induced hypertrophy; (c) increased ROS generation is not a common response of the myocyte to all hypertrophic stimuli; and (d) it may be possible to dissociate the positive inotropic effect of ouabain from its growth-related effects by alteration of the redox state of the cardiac myocyte

Symbology of Bird Motifs in Persian and Indian Carpets

The motifs used in Persian and Indian carpets are replete with concepts and symbolic meanings deeply rooted in myths, cultures and beliefs of both countries. One of these motifs is the bird motif, the symbol of freedom and salvation, which can be seen as common or specific motifs in many Persian or Indian carpets. Bird motifs have been often shown in the middle of green meadows or beautiful gardens alluding to divinity and promised paradise. As mentioned, since old motifs are strongly interwoven with mythical motifs as well as ancient symbols, the research problem of the present study is to examine the nature of such symbols applied in Persian and Indian carpets. In fact, the study aimed to reveal the symbolic meanings latent in such old motifs. In this connection, in an article entitled Naturalism and Aesthetics in Persian Carpets, Chitsazian (2006) addressed the influence of naturalism on Persian carpets. Similarly, in another article entitled Interpretation of Fish Motifs in Safavid Carpets, Sabbaghpour and Shayestehfar (2009) tried to decipher the symbolic meanings of fish motifs used in Safavid carpets with the help of verses in Rumi’s Masnavi