Search Results

1 - 10 of 562 items :

Clear All
Effect of 1-(phenyl)-N’-(4-methoxybenzylidene)-9H-pyrido[3,4-b] indole-3-carbohydrazide on in vitro poliovirus replication

Abstract

The effect of the alkaloid 1-(phenyl)-N’-(4-methoxybenzylidene)- 9H-pyrido[3,4-b]indole-3-carbohydrazide (PMC) on the poliovirus (PV) replication cycle in Vero cells was assayed by inhibition of the cytopathic effect (CPE) and inhibition of plaque forming units (PFU). Both methodologies suggested that the mode of action was avoidance of infection progression in the host cell. The compound was able to prevent CPE and PFU formation when the cells were pretreated with PMC for 24 h prior to PV infection. In addition, when the alkaloid was continuously maintained in the infected cultures, the spread of PV to adjacent cells was impaired. The pre-exposure and post-exposure prophylactic applications are possible situations in which an anti-PV drug might be used. Future studies are needed to elucidate the PMC mode of action and verify the feasibility of PMC use in vivo. No antipicornavirus agent is currently approved for clinical use

Open access
Non-commutative finite monoids of a given order n ≥ 4

Abstract

For a given integer n=p1α1p2α2pkαk (k ≥ 2), we give here a class of finitely presented finite monoids of order n. Indeed the monoids Mon(π), where

π=a1,a2,,ak|aipiαi=ai,(i=1,2,,k),aiai+1=ai,(i=1,2,,k1).
As a result of this study we are able to classify a wide family of the k-generated p-monoids (finite monoids of order a power of a prime p). An interesting di erence between the center of finite p-groups and the center of finite p-monoids has been achieved as well. All of these monoids are regular and non-commutative.

Open access
Cultural Leadership and Entrepreneurship As Antecedents of Estonia’s Singing Revolution and Post-Communist Success

Abstract

The Baltic people of Estonia, Lithuania, and Latvia gained recognition with their successful use of a cultural tool, singing folkloric songs, to protest collectively against their common Soviet oppressor in the summer of 1988, preceding the collapse of the Soviet Union. Rational-choice theorists have argued that large rebellious movements are paradoxical because the larger the number of potential revolutionaries, the greater the leadership, participation, and coordination problems they face (Olson, 1971; Tullock, 1974). This paper investigates Estonia’s Singing Revolution and illustrates how ethnic Estonians used their shared cultural beliefs and singing traditions as a tacit, informal institutional solution to overcome the collective-action problems with organizing and participating in mass singing protests against the Soviet regime. The paper goes further to extend the standard rational-choice framework and to include a more dynamic, entrepreneurial-institutional perspective on socio-cultural change by accounting for the role of cultural leaders as cultural entrepreneurs, a subset of institutional entrepreneurs. The success of Estonia’s Singing Revolution can be ultimately attributed to leadership in the form of cultural entrepreneurship going back to pre-Soviet Estonian times. The revived legacy of ancient shared beliefs, folkloric practices, and singing tradition represented the necessary social capital for the Estonian people to voice collectively shared preferences for political and economic governance during a window of constitutional opportunity. Mikhail Gorbachev’s Glasnost, a policy aimed to improve Soviet formal institutions by fostering freedom of speech and political transparency, also provided a context propitious for the Singing Revolution because it lowered the perceived costs of participation in the rebellious singing and opened a window of opportunity for political change.

Open access
The Effect of Raw Components on the Densification and Properties of Nanostructured Sialon Materials / Izejas materiālu ietekme uz nanostrukturētu sialona materiālu saķepšanu un īpašībām

References 1. Schulz, I., Herrmann, M., Endler, I., Zalite, I., Speisser, B., Kreusser, J. Nano Si3N4 composites with improved tribological properties. Lubrication Science, 2009, vol. 21, pp. 69-81. http://dx.doi.org/10.1002/ls.72 2. Gogotsi, Yu. G. Particulate silicon nitride-based composites. J. Mater. Sci., 2000, vol. 29, pp. 2541-2556. http://dx.doi.org/10.1007/BF00356803 3. Petzow, G., Hermann, M. Silicon nitride ceramics. Structure and Bonding. Springer, Berlin, 2002, vol. 102, pp. 71-72. 4

Open access
Preclinical studies of [61Cu]ATSM as a PET radiopharmaceutical for fibrosarcoma imaging

0969-8051(98)00113-9. J. S. Lewis, T. L. Sharp, R. Laforest, Y. Fujibayashi and M. J. Welch, Tumor uptake of copper-diacetyl-bis(N4-methylthiosemicarbazone): effect of changes in tissue oxygenation, J. Nucl. Med.   42 (2001) 655-661. F. Dehdashti, M. A. Mintun, J. S. Lewis, J. Bradley, R. Govindan, R. Laforest, M. J. Welch and B. A. Siegel, In vivo assessment of tumor hypoxia in lung cancer with 60 Cu-ATSM, Eur. J. Nucl. Med. Mol. Imag.   30 (2003) 844-840. A. R. Jalilian, M. Sabet, P

Open access
Corrosion Inhibition of Mild Steel in Nitric Acid Media by some Schiff Bases Derived from Anisalidine

Corrosion inhibition performance of mild steel in nitric acid solution containing different concentration of anisalidine derivative Schiff bases viz. N- (4-nitro phenyl) p-anisalidine (SB1), N- (4-chloro phenyl) p-anisalidine (SB2), N- (4-phenyl) p-anisalidine (SB3), N- (4-methoxy phenyl) p-anisalidine (SB4), N- (4-hydroxy phenyl) p-anisalidine (SB5) has been investigated using mass loss, thermometric and potentiostate polarization technique. Inhibition efficiencies of Schiff bases have been evaluated at different acid strength. The inhibition efficiency was found larger than their parent amines. Inhibition efficiencies of synthesized Schiff bases increase with inhibitor concentration. Inhibition efficiency increases up to 98.32% with ansalidine derivative Schiff base.

Open access
Design and synthesis of novel thiophenecarbohydrazide, thienopyrazole and thienopyrimidine derivatives as antioxidant and antitumor agents

, E. N. Amin and L. Ramadan, Synthesis of 2-[(5,6,7,8-tetrahydrobenzo [ b ] thieno[2,3- d ]pyrimidin-4-y)thio]- N -(4-aryl-3-chloro-2-oxoazetidin-1-yl) acetamides and biochemical screening for radioprotective character, Egypt. J. Biotechnol.   4 (1998) 16-30; ref. Chem. Abstr.   132 (2000) 49937. H. N. Hafez and A. B. A. El-Gazzar, Design and synthesis of 3-pyrazolyl-thiophene, thieno [2,3- d ] pyrimidines as new bioactive and pharmacological activities, Bioorg. Med. Chem. Lett.   18 (2008) 5222-5227; DOI: 10.1016/j.bmcl.2008

Open access
Seismic Isolation of Bridges Using the Principle of Electromagnetic Attraction and Repulsion

REFERENCES [1]. S. USUBA, R.B. HEIMANN: “Dense Si 3 N 4 Coatings with High Friction Coefficient Deposited by High-Velocity Pulsed Plasma Spraying” , Journal of Thermal Spray Technology, Volume 15(3) September 2006 [2] AMERICAN SOCIETY FOR METALS: „ Metals Handbook ”, 8th edition, Vol. 1, p792, 1966 [3]. R.A. MATULA: „ Electrical Resistivity of Copper, Gold, Palladium and Silver ” J. Phys. Chem. Ref. Data, Vol. 8, No. 4, 1979 [4]. U.T.C.B.: „ Cod de Proiectare Seismică P100-1 ”, 2013 [5]. G. RODOLFO SARAGONI, GARY C. HART

Open access
Characterizing which Powers of Hypercubes and Folded Hyper- cubes Are Divisor Graphs

Abstract

In this paper, we show that Qk n is a divisor graph, for n = 2, 3. For n ≥ 4, we show that Qk n is a divisor graph iff k ≥ n − 1. For folded-hypercube, we get FQn is a divisor graph when n is odd. But, if n ≥ 4 is even integer, then FQn is not a divisor graph. For n ≥ 5, we show that (FQn)k is not a divisor graph, where 2 ≤ k ≤ [n/2] − 1.

Open access
Molecular epidemiology of Crimean–Congo hemorrhagic fever virus in ticks collected from western Iran

, NY, USA) and P < 0.05 was considered significant. Results A total of 881 hard ticks were collected from 141 sheep and goats in the present study. All ticks belonged to 3 genera including, Rhipicephalus (95.6%, n = 842), Hyalomma (4.1%, n = 36) and Haemaphysalis (0.4%, n = 4). The most frequently detected species was R. sanguineus (65.1%, n = 574), followed by R. bursa (29.3%, n = 258). The remaining ticks were as follows: R. sp (0.9%, n = 8,), Hy. anatolicum (1.6%, n = 14), Hy. asiaticum (1%, n = 9), Hy. dromedarii (0.68%, n = 6), Hy

Open access