Synthetic, spectroscopic, magnetic, and x-ray structural studies on a vitamin B6-amino acid Schiff base complex, aqua(5'-phosphopyridoxylidenetyrosinato)copper(II) tetrahydrate

A Schiff base metal complex, [Cu(II)(PLP-DL-tyrosinato)(H2O)].4H2O (PLP = pyridoxal phosphate), with the molecular formula CuC17O13N2H27P has been prepared and characterized by magnetic, spectral, and X-ray structural studies. The compound crystallizes in the triclinic space group P1BAR with a = 8.616 (2) angstrom, b = 11.843 (3) angstrom, c = 12.177 (3) angstrom, alpha = 103.40 (2)degrees, beta = 112.32 (2)degrees, gamma = 76.50 (1)degrees, and Z = 2. The structure was solved by the heavy-atom method and refined by least-squares techniques to a final R value of 0.057 for 3132 independent reflections. The coordination geometry around Cu(II) is distorted square pyramidal with phenolic oxygen, imino nitrogen, and carboxylate oxygen from the Schiff base ligand and water oxygen as basal donor atoms. The axial site is occupied by a phosphate oxygen from a neighboring molecule, thus resulting in a one-dimensional polymer. The structure reveals pi-pi interaction of the aromatic side chain of the amino acid with the pyridoxal pi system. A comparative study is made of this complex with similar Schiff base complexes. The variable-temperature magnetic behavior of this compound shows a weak antiferromagnetic interaction.

The first structurally characterized diruthenium(II,III) complex with four bridging arylcarboxylato ligands

The diruthenium(II,III) compound [Ru2Cl(O2CC6H4-p-OMe)4](H2O)0.25 (1) has been prepared and its crystal structure determined by X-ray studies. The crystals belong to the triclinic space group, PImage , and the asymmetric unit consists of one full dimer and two half dimers. The {Ru2(O2CC6H4-p-OMe)4+} units are bridged by chloride ions into an infinite zigzag chain, with an average Ru---Cl distance and Ru---Cl---Ru angle of 2.567(2) Å and 121.0(1)°, respectively. The average Ru---Ru distance of 2.286(1) Å in 1 is comparable with that in analogous tetra-alkylcarboxylates, Ru2Cl(O2CR)4 and tetra-amidates, Ru2Cl(ArCONH)4.

Nucleosome core histone complex isolated gently and rapidly in 2 M NaCl is octameric

A relatively stable specific complex of the chromatin core histones H2A, H2B, H3, and H4 has been obtained in 2 M NaCl/25 mM sodium phosphate buffer, pH 7.0. The histone core complex has an apparent specific volume of 0.73 ml/g. Its sedimentation coefficient was dependent on rotor speed (angular velocity, omega) and attained different stable values at low and high rotor speeds. The drop in sedimentation coefficient occurred sharply between omega 2 values of about 9 x 10(6) and 1.1 x 10(7) (radians/sec)2. The s020,w corresponding to zero angular velocity (1 atmosphere pressure) was 6.6 S +/- (SEM) 0.1 S. At high rotor speeds the value decreased to 3.8 S +/- 0.1 S. The core complex has a diffusion coefficient, D20,w, of 5.4 x 10(-7) cm2/sec and a molecular weight of 108,000 +/- (SD) 2500.

Nuclear-quadrupole resonance in coordination chemistry- identification of bridiging and therminal chlorines in the mercuric chloride-4-picoline n-oxide complex

The temperature dependence of the chlorine-35 n.q.r. in the mercuric chloride-4-picoline N-oxide complex has been studied from 77 K to room temperature, and the results are used to assign the observed frequencies to terminal and bridging chlorines.

The Liminality of Cosmopolitanism from the Global South – Transnational Activists in Costa Rica between Colonial Legacies and Decolonial Attitudes

The Master’s thesis examines whether and how decolonial cosmopolitanism is empirically traceable in the attitudes and practices of Costa Rican activists working in transnational advocacy organizations. Decolonial cosmopolitanism is defined as a form of cosmopolitanism from below that aims to propose ways of imagining – and putting into practice – a truly globe-encompassing civic community not based on relations of domination but on horizontal dialogue. This concept has been developed by and shares its basic presumptions with the theory on coloniality that the modernity/coloniality/decoloniality research group is putting forward. It is analyzed whether and how the workings of coloniality as underlying ontological assumption of decolonial cosmopolitanism and broadly subsumable under the three logics of race, capitalism, and knowledge, are traceable in intermediate postcolonial transnational advocacy in Costa Rica. The method of analysis chosen to approach these questions is content analysis, which is used for the analysis of qualitative semi-structured in-depth interviews with Costa Rican activists working in advocacy organizations with transnational ties. Costa Rica was chosen as it – while unquestionably a Latin American postcolonial country and thus within the geo-political context in which the concept was developed – introduces a complex setting of socio-cultural and political factors that put the explanatory potential of the concept to the test. The research group applies the term ‘coloniality’ to describe how the social, political, economic, and epistemic relations developed during the colonization of the Americas order global relations and sustain Western domination still today through what is called the logic of coloniality. It also takes these processes as point of departure for imagining how counter-hegemonic contestations can be achieved through the linking of local struggles to a global community that is based on pluriversality. The issues that have been chosen as most relevant expressions of the logic of coloniality in the context of Costa Rican transnational advocacy and that are thus empirically scrutinized are national identity as ‘white’ exceptional nation with gender equality (racism), the neoliberalization of advocacy in the Global South (capitalism), and finally Eurocentrism, but also transnational civil society networks as first step in decolonizing civic activism (epistemic domination). The findings of this thesis show that the various ways in which activists adopt practices and outlooks stemming from the center in order to empower themselves and their constituencies, but also how their particular geo-political position affects their work, cannot be reduced to one single logic of coloniality. Nonetheless, the aspects of race, gender, capitalism and epistemic hegemony do undeniably affect activist cosmopolitan attitudes and transnational practices. While the premisses on which the concept of decolonial cosmopolitanism is based suffer from some analytical drawbacks, its importance is seen in its ability to take as point of departure the concrete spaces in which situated social relations develop. It thus allows for perceiving the increasing interconnectedness between different levels of social and political organizing as contributing to cosmopolitan visions combining local situatedness with global community as normative horizon that have not only influenced academic debate, but also political projects.

Device for reusing damaged laser mirrors

A simple mirror holder which permits the use of locally damaged laser morrors by allowing the undamaged areas of the reflector to be aligned along the laser optic axis is described. The mirror holder has an eccentric step for housing the mirror and a concentric aperture through which the undamaged surface of the reflector is utilised. By varying the eccentricity and by rotating the mirror inside the step the entire surface area of the reflector can be used successively.

Photo-activated cytotoxicity of a pyrenyl-terpyridine copper(II) complex in HeLa cells

Terpyridine copper(II) complexes Cu(L)(2)](NO3)(2) where L is (4'-phenyl)-2 2' 6' 2 `'-terpyridine (ph-tpy in 1) and 4-(1 pyrenyl)]-2 2' 6' 2'-terpyridine (py-tpy in 2) are prepared characterized and their photocytotoxic activity studied The crystal structure of complex 1 shows distorted octahedral CuN6 coordination geometry The 1 2 electrolytic and one-electron paramagnetic complexes show a visible band near 650 nm in DMF-H2O The complexes show emission band at 352 nm for 1 and 425 nm for 2 when excited at 283 and 346 nm respectively The Cu(II)-Cu(I) redox couple is observed near -0 2 V versus SCE in DMF-0 1 m TBAP The complexes are avid partial-intercalative binders to calf thymus DNA giving binding constant (K-b) values of similar to 10(6) M-1 Complex 2 with its photoactive pyrenyl moiety exhibits significant photocleavage of pUC19 DNA in red light via singlet oxygen pathway Complex 2 also exhibits significant photo-activated cytotoxicity in HeLa cancer cells in visible light giving IC50 value of 11 9 mu M while being non-toxic in dark with an IC50 value of 130 5 mu M (C) 2010 Elsevier Ltd All rights reserved

Thunderstorm climatology and lightning location applications in northern Europe

Thunderstorm is a dangerous electrical phenomena in the atmosphere. Thundercloud is formed when thermal energy is transported rapidly upwards in convective updraughts. Electrification occurs in the collisions of cloud particles in the strong updraught. When the amount of charge in the cloud is large enough, electrical breakdown, better known as a flash, occurs. Lightning location is nowadays an essential tool for the detection of severe weather. Located flashes indicate in real time the movement of hazardous areas and the intensity of lightning activity. Also, an estimate for the flash peak current can be determined. The observations can be used in damage surveys. The most simple way to represent lightning data is to plot the locations on a map, but the data can be processed in more complex end-products and exploited in data fusion. Lightning data serves as an important tool also in the research of lightning-related phenomena, such as Transient Luminous Events. Most of the global thunderstorms occur in areas with plenty of heat, moisture and tropospheric instability, for example in the tropical land areas. In higher latitudes like in Finland, the thunderstorm season is practically restricted to the summer season. Particular feature of the high-latitude climatology is the large annual variation, which regards also thunderstorms. Knowing the performance of any measuring device is important because it affects the accuracy of the end-products. In lightning location systems, the detection efficiency means the ratio between located and actually occurred flashes. Because in practice it is impossible to know the true number of actually occurred flashes, the detection efficiency has to be esimated with theoretical methods.

X-ray studies on crystalline complexes involving amino acids and peptides. XXI. Structure of a (1:1) complex between L-phenylalanine and D-valine

CsHllNO2.C9HilNO2, Mr = 282.3, P1, a = 5.245 (1), b = 5.424 (1), c = 14.414 (2) A, a = 97.86 (1), fl = 93-69 (2), y = 70-48 (2) °, V= 356 A 3, Z = 1, O m = 1-32 (2), Dx = 1.32 g cm-3, h(Mo Ka) = 0-7107 A, g = 5-9 cm-1, F(000) = 158, T= 298 K, R=0.035 for 1518 observed reflections with I>2tr(I). The molecules aggregate in double layers, one ayer made up of L-phenylalanine molecules and the other of D-valine molecules. Each double layer is stabilized by interactions involving main-chain atoms of both types of molecules. The interactions include hydrogen bonds which give rise to two head-to-tail sequences. The arrangement of molecules in the complex is almost the same as that in the structure of DL-valine (and DL-leucine and DL-isoleucine) except for the change in the side chain of L molecules. The molecules in crystals containing an equal number of L and O hydrophobic amino-acid molecules thus appear to aggregate in a similar fashion, irrespective of the precise details of the side chain.

Reacting to Complex Threats – the Securitization in the Speeches of Anders Fogh Rasmussen based on NATO´s New Strategic Concept

The purpose of this master´s thesis is to analyze how NATO Secretary General Anders Fogh Rasmussen is trying to justify the existence of the military alliance through the use of security arguments. I am puzzled by the question: why does NATO still exist – what is NATO’s raison d'être. The New Strategic Concept (2010) forms the base for his argumentation. This thesis focuses on the security argumentation of NATO which is examined by analyzing the speeches the Secretary General. The theoretical framework of this study is based on constructivist approach to international security examining the linguistic process of securitization. Issues become securitized after Anders Fogh Rasmussen names them as threats. This thesis focuses on the securitization process relating to NATO and analyses what issues Rasmussen raises to the security agenda. Research data consists of the speeches by Anders Fogh Rasmussen. They are analyzed through J.L. Austin’s speech act taxonomy and Chaïm Perelman’s argumentation theories. The thesis will concentrate on the formulation and articulation of these threats which are considered and coined as “new threats” in contemporary international relations. I am conducting this research through the use of securitization theory. This study illustrates that the threats are constructed by NATO’s member-states in unison, but the resolutions are sounded through Rasmussen’s official speeches and transcripts. . Based on the analysis it can be concluded that Rasmussen is giving reasons for the existence of NATO. This takes place by making use of speech acts and different rhetorical techniques. The results of the analysis indicate that NATO remains an essential organization for the West and the rest of the world according to the Secretary General.

Molecular Modeling Studies on Amphotericin B and its Complex with Phospholipid,

Molecular dynamics simulation studies on polyene antifungal antibiotic amphotericin B, its head-to-tail dimeric structure and lipid - amphotericin B complex demonstrate interesting features of the flexibilities within the molecule and define the optimal interactions for the formation of a stable dimeric structure and complex with phospholipid.