scholarly journals Photoinduced C(sp3)–H Sulfination Empowers a Direct and Chemoselective Introduction of the Sulfonyl Group

2021 ◽  
Author(s):  
Shengfei Jin ◽  
Graham C. Haug ◽  
Ramon Trevino ◽  
Viet D Nguyen ◽  
Hadi Arman ◽  
...  
Keyword(s):  
Central Position ◽  
Organosulfur Compounds ◽  
Sulfonyl Group

Direct installation of the sulfinate group by a functionalization of unreactive aliphatic C–H bonds can provide an entry to most classes of organosulfur compounds, because of the central position of...

Characteristics of the Interaction between Thrombin Exosite1 and the Sequence 269-297 of Platelet Glycoprotein Ibα

1998 ◽  
Vol 80 (08) ◽  
pp. 310-315 ◽  
Author(s):  
Marie-Christine Bouton ◽  
Christophe Thurieau ◽  
Marie-Claude Guillin ◽  
Martine Jandrot-Perrus
Keyword(s):  
Platelet Activation ◽  
Electrostatic Interactions ◽  
Platelet Glycoprotein ◽  
Thrombin Receptor ◽  
Central Position ◽  
Amidolytic Activity ◽  
N Terminus ◽  
Hydrolysis Of ◽  
Chemical Cross Linking ◽  
Positively Charged

SummaryThe interaction between GPIb and thrombin promotes platelet activation elicited via the hydrolysis of the thrombin receptor and involves structures located on the segment 238-290 within the N-terminal domain of GPIbα and the positively charged exosite 1 on thrombin. We have investigated the ability of peptides derived from the 269-287 sequence of GPIbα to interact with thrombin. Three peptides were synthesized, including Ibα 269-287 and two scrambled peptides R1 and R2 which are comparable to Ibα 269-287 with regards to their content and distribution of anionic residues. However, R2 differs from both Ibα 269-287 and R1 by the shifting of one proline from a central position to the N-terminus. By chemical cross-linking, we observed the formation of a complex between 125I-Ibα 269-287 and α-thrombin that was inhibited by hirudin, the C-terminal peptide of hirudin, sodium pyrophosphate but not by heparin. The complex did not form when γ-thrombin was substituted for α-thrombin. Ibα 269-287 produced only slight changes in thrombin amidolytic activity and inhibited thrombin binding to fibrin. R1 and R2 also formed complexes with α-thrombin, modified slightly its catalytic activity and inhibited its binding to fibrin. Peptides Ibα 269-287 and R1 inhibited platelet aggregation and secretion induced by low thrombin concentrations whereas R2 was without effect. Our results indicate that Ibα 269-287 interacts with thrombin exosite 1 via mainly electrostatic interactions, which explains why the scrambled peptides also interact with exosite 1. Nevertheless, the lack of effect of R2 on thrombin-induced platelet activation suggests that proline 280 is important for thrombin interaction with GPIb.

Kreation und Zeit

2006 ◽  
Vol 51 (1) ◽  
pp. 118-133
Author(s):  
Renate Schlesier
Keyword(s):  
Central Position ◽  
Intellectual Work ◽  
Eine Analyse ◽  
Artistic Production ◽  
Poetic Creation

Das Inspirationskonzept ist für Prousts selbstreflexive Bestimmung künstlerischer Produktion von zentraler Bedeutung (dies läßt sich durch eine Analyse von Textstellen sowohl aus dem letzten Teil von Prousts Recherche als auch aus dem Kontext von Jean Santeuil und Contre Sainte-Beuve zeigen). Prousts spezifische Bestimmung der Inspiration als etwas, das auf intellektuelle Arbeit nicht verzichten kann, unterminiert jedoch antiintellektualistische platonische Dichtungslehren. Dies impliziert zudem, daß Proust die Kluft zwischen Künstlern und Nicht-Künstlern für unüberbrückbar erklärt. Inspiration ist für Proust etwas Verzauberndes, weil sie wiedergefundene Zeit ist, die jedoch erst im poetischen Kreationsprozeß Gestalt gewinnt. The concept of inspiration occupies a central position in the realm of Proust’s self-reflexive evaluation of artistic production (as can be demonstrated by an analysis of passages bothfrom the last part of Proust’s ›Recherche‹ and from the context of ›Jean Santeuil‹ and ›Contre SainteBeuve‹). Yet by evaluating inspiration as something that could not do without intellectual work, Proust undermines anti-intellectualistic platonizing poetics. In addition, this implies that Proust declares the gap between artists and non-artists as unbridgeable. For Proust, inspiration is enchanting because it is time regained, but takes shape only in the process of poetic creation.

The Features of B. Shergin’s Cognitive Style (On the Example of the Conceptualization of the Image of the Sea)

2020 ◽  
Vol 81 (1) ◽  
pp. 73-81
Author(s):  
T. A. Sidorova
Keyword(s):  
Cognitive Style ◽  
World View ◽  
Literary Text ◽  
Central Position ◽  
Special Role ◽  
Cognitive Mechanisms ◽  
Cognitive Poetics ◽  
Conceptual Structures ◽  
The People ◽  
Artistic Image

The main aim of this research was to identify the features of B. V. Shergin’s cognitive style through comprehension of the artistic image of the sea in the works of this writer. An analysis of this image was conducted from the standpoint of cognitive poetic. Cognitive poetic is considered as the main method of linguopoetic interpretation of a literary text, whose basic principles include analysis of conceptual structures reflected in the text. In the process of research, the concept of “cognitive style” in correlation with the literary text was clarified, The components of cognitive style, objectified by the image of the sea were specified. Since the literary text was interpreted from the position of cognitive poetics, the main attention was paid not only to linguistic, but also to mental structures. Furthermore, the article explores the wellknown structures of knowledge: presuppositions, concepts, motives, ideas, etc., along with semantic dominants and semantic constructs as strong meaning formations, which are determined by the author’s needs, values, world view and world perception. Therefore, the process of text interpretation takes into account the specificity of linguistic and artistic consciousness of the author, including features of the socio-cultural consciousness of Pomors (members of a subculture). The study showed that each component of B. V. Shergin’s cognitive style has its specific characteristics. The manner of presenting information in the text is characterized by a special emotional tension: understandable and close to the people daily life gets an ontological understanding. Among the cognitive mechanisms, the secondary conceptualization of the concepts of Russian Northern culture plays a special role: many of them acquire a sign of spirituality. It is shown that the specifics of the author’s cognitive style is determined by the features of his consciousness; therefore, the knowledge as sententias, semantic dominants, semantic constructs, stereotypes, values and oppositions holds the central position.

Labour Content and Structure of Pakistan's Manufactured Exports

1977 ◽  
Vol 16 (4) ◽  
pp. 383-404
Author(s):  
Surraiya Nlshat
Keyword(s):  
Central Position ◽  
Manufactured Exports ◽  
Capital Intensive

The Heckscher-Ohlin (H-O) theorem occupies a central position in the discussion of the pattern of trade between countries. According to this theorem a country should specialize in the production and export of those commodities which require more of those factors with which the country is relatively well endowed, i.e., a labour-abundant country should export labour-intensive product and a capital-abundant economy should export capital-intensive goods.

Segetal vegetation of the South Urals: the alliances Caucalidion Tx. ex von Rochow 1951 and Lactucion tataricae Rudakov in Mirkin et al. 1985

2019 ◽  
pp. 118-134
Author(s):  
G. R. Khasanova ◽  
S. M. Yamalov ◽  
M. V. Lebedeva ◽  
Z. Kh. Shigapov
Keyword(s):  
Steppe Zone ◽  
Species Number ◽  
Central Position ◽  
South Urals ◽  
Forest Steppe ◽  
The South ◽  
Row Crops ◽  
Winter Cereals ◽  
Weed Communities ◽  
Chernozem Soils

Segetal, or weed, communities are the stands of the weed plant species which are formed under the influence of edafo-climatic conditions and the mode of soil disturbance within the processing of crop rotation (agrotechnical factor) (Mirkin, Naumova, 2012). This paper is the second part of weed community study in the South Ural, assigned to the class Papaveretea rhoeadis S. Brullo et al. 2001, syntaxon unites the weed communities of winter cereals with two orders: Aperetalia spica-venti J. Tx. et Tx. in Malato-Beliz et al. 1960 and Papaveretalia rhoeadis Hüppe et Hofmeister ex Theurillat et al. 1995; and three alliances (Khasanova et al., 2018). Data on diversity, floristic, ecological and spatial differentiation of mesoxeric and xeric weed communities of the alliances Caucalidion Tx. ex von Rochow 1951 and Lactucion tataricae Rudakov in Mirkin et al. 1985 in steppe and southern part of the forest-steppe zones are given (Table 1; Fig. 1). The dataset contains 756 relevés: 647 made by authors during the field seasons of 2002–2018, while 109 taken from published monography (Mirkin et al., 1985). The alliance Caucalidion combines weed communities on rich carbonate chernozem soils in the forest-steppe zone. Diagnostic species are Galeopsis bifida, G. ladanum, Galium aparine, Erodium cicutarium, Persicaria lapathifolia, Silene noctiflora, Thlaspi arvense. This alliance occupies the central position within class between communities of forest zone of the alliance Scleranthion annui and these of the steppe zone of the alliance Lactucion tataricae. The last alliance combines weed communities of the steppe zone and southern part of the forest-steppe one on south and typical chernozem soils. Two species are diagnostic: Lactuca tatarica and Panicum miliaceum. Alliances are differentiated in sample plot species richness and coenoflora: 145 species in alliance Caucalidion coenoflora (mean species number per plot is 16), and 207 species in that of Lactucion tataricae (consequently 13 species). There are 8 associations, 4 subassociations, 6 variants, 1 unrank community within these two alliances, among which 5 associations and all subassociations are new. The alliance Caucalidion includes 4 associations with spatiall and crop differentiation, which are mainly character for the forest-steppe part of the Trans-Urals within the bounds of forest-steppe region of the eastern slope of the Southern Urals. Two associations are new: Cannabio ruderalis–Galeopsietum ladani ass. nov. hoc loco (Table 2; holotypus hoc loco — rele­vé 7) unites weed communities of winter, less often — spring crops; Lycopsio arvensis–Camelinetum microcarpae ass. nov. hoc loco (Table 4; holotypus hoc loco — relevé 3) unites weed communities of row crops, mainly sunflower, less often — cereals. In the same area the communities of the ass. Cannabio ruderalis–Sinapietum arvensis Rudakov in Mirkin et al. 1985 (Table 3) unite the weed communities of mainly winter cereals — wheat and rye. These communities, described in 1980s, previously were widespread in the Trans-Urals (Mirkin et al., 1985), while now occur locally in the northern part of this area. The communities of ass. Centaureo cyani–Stachyetum annuae Abramova in Mirkin et al. 1985, also described in the 1980s, were not found in the 2010s. The diversity of the most xerophytic alliance Lactucion tataricae is represented by 4 associations which occur both in the Trans-Urals and the Cis-Urals. The most common in the last area are weed row crops (beet, nute, flax, sunflower, corn, peas, buckwheat) communities of the ass. Echinochloo crusgalli–Panicetum miliacei ass. nov. hoc loco (Table 5; holotypus hoc loco — relevé 5. They are common in five natural districts: Predbelskiy forest-steppe one, forest and fo­rest-steppe of Belebey Upland, Cis-Urals steppe one, forest and forest-steppe one on Zilair Plateu, and Zabelskiy district of the broad-leaved forests. The weed communities of spring and winter cereals of the ass. Lathyro tuberosi–Convolvuletum arvensis ass. nov. hoc loco (Table 6; holotypus hoc loco — relevé 5) are common only within the Cis-Urals steppe district. The communities of ass. Lactuco serriolae–Tripleurospermetum inodori ass. nov. hoc loco (Table 7; holotypus hoc loco — relevé 2) which unites the weed communities of winter cereals, are common in the steppe zone and the southern part of the forest steppe one of the Trans-Urals and the Cis-Urals within the Cis-Urals steppe, Trans-Urals steppe, and Predbelskiy forest-steppe districts. The communities of the ass. Lactucetum tataricae Rudakov in Mirkin et al. 1985 are associated exclusively with the steppe zone of the Trans-Urals. The Lactuca tatarica community (Table 8), distributed in the steppe and southern part of the forest steppe zones of the Trans-Urals, probably is derived from the ass. Lactucetum tataricae under the intensive chemical weeding of cereal crops. Floristic differentiation of associations is confirmed by the results of the ordination analysis (Fig. 2), the diagram of which shows the distribution of communities along the moisture (first axis) and the complex soil richness–salinity gradient and agrocoenotic factor (second axis).

Foundations and Introduction of Islamic Economics: Role and Trends

2020 ◽  
Vol 3 (3) ◽  
pp. 121-138
Author(s):  
Dr. Bilal Ahmad Khan
Keyword(s):  
Modern Science ◽  
Central Position ◽  
Islamic Philosophy ◽  
Moral Training ◽  
Human Ability ◽  
The Status ◽  
Distribution Of Resources ◽  
The Rich ◽  
Specific Concept ◽  
The Individual

Islamic economics based on specific concept of universe and the creation of man is contradictory to the concept adopted and accepted by modern science. Islamic economics postulates although ability and expertise is required for progress and growth but distribution of resources completely dependent on it would be cruel, inhuman and bereft of kindness, and lead to oppression. Islamic economics does not favor making human ability and expertise the fulcrum of resource distribution. It should be kind, considerate and based on justice and fairness. This is because according to Islamic philosophy, ownership is considered to be a trust from Allah which has been bestowed on the rich so that they may utilize it correctly. In Islamic economics the role of the individual, has inclinations and his aims and objectives occupy a central position and are vitally important. He is definitely a rational being but his level of rationality is not confined to the calculations of cost and profit. An individual does not want merely to obtain monetary profit and physical pleasure and leisure but he also wants and aims for something beyond what the material world has to offer. The main aim of the study is to find out the relationship between Islam and economics. In Islamic economics the comprehensive moral training of the individual, his technical and educational ability, his aims and his priorities are of primary importance. According to Islamic economics the means of acquiring wealth has the same importance as wealth itself. Dishonesty, abuse of trust and earning of wealth through fraudulent ways and means may perhaps increase the status of an individual but the society suffers because of it on the whole. This leads to an unjust and oppressive economic system.

Designs

2018 ◽  
Author(s):  
Vijaya Nagarajan
Keyword(s):  
20Th Century ◽  
Historical Perspective ◽  
Central Position ◽  
Symbolic Meanings

This chapter focuses on types of kōlam designs. The basic categories are katta (squares) and pulli (dots). The highly ritualized forms are the navagraha (nine heavenly bodies, including the five planets) and yantras. The symbolic meanings of geometric, figurative, and landscape kōlams, whether they are itheegam (traditional) and nagareegam (modern), are discussed. Kōlam-making tools are explained, such as the traditional personal notebooks and printed pamphlets and more modern stencils and plastic stick-on decals. A discussion of an 1884 kōlam chapbook and other chapbooks from the 20th century gives a historical perspective. The 20th-century Indian choreographer Chandralekha gave kōlam designs a central position in her work.

Epilogue

2017 ◽  
Author(s):  
Erika Fischer-Lichte
Keyword(s):  
Central Position ◽  
Short Discussion ◽  
German Culture ◽  
Ancient Athens

The book concludes with an epilogue entitled ‘The Return of Dionysus. From Festive Performances to Global Spectacle’. It very briefly retraces the exchange of productions of Greek tragedies between Germany and other countries and ends with the role played by productions of Greek tragedies today, at German as well as international theatre festivals, thus linking them back to the most important festival in ancient Athens, the Great Dionysia. After explaining how such festivals in Germany reassert the central position held by theatre in German culture, the epilogue ends with a short discussion of Jan Fabre’s twenty-four-hour performance Mount Olympus—to Glorify the Cult of Tragedy (Berliner Festspiele, June 2015) as an allegory of and a reflection on Greek tragedy’s endurance on the German stage.

Maritime and River Traders, Landing Places, and Emporia Ports in the Merovingian Period in and Around the Low Countries

2020 ◽  
pp. 763-796
Author(s):  
Dries Tys
Keyword(s):  
North Sea ◽  
Institutional Economics ◽  
New Institutional Economics ◽  
Central Position ◽  
Economic Activities ◽  
Early Medieval ◽  
Low Countries ◽  
Long Distance ◽  
The North ◽  
The North Sea

The origin, rise, and dynamics of coastal trade and landing places in the North Sea area between the sixth and eighth centuries must be understood in relation to how coastal regions and seascapes acted as arenas of contact, dialogue, and transition. Although the free coastal societies of the early medieval period were involved in regional to interregional or long-distance trade networks, their economic agency must be understood from a bottom-up perspective. That is, their reproduction strategies must be studied in their own right, independent from any teleological construction about the development of trade, markets, or towns for that matter. This means that the early medieval coastal networks of exchange were much more complex and diverse than advocated by the simple emporium network model, which connected the major archaeological sites along the North Sea coast. Instead, coastal and riverine dwellers often possessed some form of free status and large degrees of autonomy, in part due to the specific environmental conditions of the landscapes in which they dwelled. The wide estuarine region of the Low Countries, between coastal Flanders in the south and Friesland in the north, a region with vast hinterlands and a central position in northwestern Europe, makes these developments particularly clear. This chapter thus pushes back against longstanding assumptions in scholarly research, which include overemphasis of the influence of large landowners over peasant economies, and on the prioritization of easily retrievable luxuries over less visible indicators of bulk trade (such as wood, wool, and more), gift exchange, and market trade. The approach used here demonstrates that well-known emporia or larger ports of trade were embedded in the economic activities and networks of their respective hinterlands. Early medieval coastal societies and their dynamics are thus better understood from the perspective of integrated governance and economy (“new institutional economics”) in a regional setting.

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