bluuebunny/crossref_metadata_2025 huggingface dataset:
Geochemistry and Provenance of Maastrichtian Clastic Rocks in the Dikmendede Formation of Orhaniye in Kazan‐Ankara‐Turkey Region
Authors: OZKAN Ali Mujdat , AYAZ‐BOZDAG Ayla
Published: October 2011

An integrated petrographic and geochemical study of the sandstones of the Maastrichtianaged in the Orhaniye (Kazan‐Ankara‐Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting. Depending on their matrix and mineralogical content, the Maastrichtian sandstones are identified as lithic arenite/wacke. The Dikmendede sandstones derived from types of provenances, the recycled orogen and recycled transitional. The chemical characteristics of the Dikmendede sandstones, i.e., fairly uniform compositions, high Th/U ratios (>3.0), negative Eu anomalies (Eu/Eu* 0.72–0.99) and Th/Sc ratios (mostly less than 1.0), favor the OUC (old upper continental crust) provenance for the Dikmendede sandstones. The SiO2/Al2O3, Th/Sc (mostly <1.0) and La/Sc (<4.0) ratios are; however, slightly lower than typical OUC, and these ratios may suggest a minor contribution of young arc‐derived material. The rare earth element (REE) pattern, and La/Sc versus Th/Co plot suggests that these sediments were mainly derived from felsic source rocks. The Dikmendede sandstones have high Cr (123–294 ppm) and Ni (52–212 ppm) concentrations, Cr/Ni ratio of 1.93, and a medium correlation coefficient between Cr and Ni and corresponding medium to high correlation of both (Cr and Ni, respectively) elements with Co. These relationships indicate a significant contribution of detritus from ophiolitic rocks. As rare earth element data are available for the Dikmendede sandstones, the Eu/Eu* is compared with LaN/YbN. Samples plot in the area of overlapping between continental collision, strike‐slip and continental arc basins. The predominantly felsic composition of the Dikmendede sandstones is supported by the REE plots, which show enriched light REE, negative Eu anomaly and flat or uniform heavy REE. The Dikmendede sandstones have compositions similar to those of the average upper continental crust and post‐Archean Australian shales. This feature indicates that the sediments were derived mainly from the upper continental crust. The Dikmendede sandstones have chemical index of alteration (CIA) values of 28–49, with an average of 40 indicating a low degree of chemical weathering in the source area. The compositional immaturity of the analyzed sandstone samples is typical of subduction‐related environments, and their SiO2/Al2O3 and K2O/Na2O ratios and Co, Sc, Th and Zr contents reflect their oceanic and continental‐arc settings. The Dikmendede sandstones were developed as flysch deposits derived from mixed provenance in a collision belt.
Features of Sandy Debris Flows of the Yanchang Formation in the Ordos Basin and Its Oil and Gas Exploration Significance
Authors: LI Xiangbo , CHEN Qilin , LIU Huaqing , WAN Yanrong , WEI Lihua , LIAO Jianbo , LONG Liwen
Published: October 2011

Sandy debris flow is a new genetic type of sand bodies, which has gained much attention in recent years and its corresponding theory is proved to be a significant improvement and even partial denial to the “Bouma Sequence” and “turbidite fan” deep‐water sedimentary theories to some point. Oil exploration researchers are highly concerned with sandy debris flows for its key role in controlling oil and gas accumulation processes. In this article, by applying sandy debris flows theory and combining a lot work of core, outcrop observation and analysis plus seismic profile interpretation, we recognized three types of sedimentary gravity flows that are sandy debris flows, classic turbidites and slumping rocks in chang‐6 member of Yanchang Formation in the deep‐water area of central Ordos Basin. Among the three types, the sandy debris flows are the most prominent and possesses the best oil bearing conditions. On the contrary, the classic turbidites formed by turbidity currents are limited in distribution; therefore, previous Yanchang Formation deep‐water sedimentary studies have exaggerated the importance of turbidite currents deposition. Further study showed that the area distribution of deep water gravity flow sand bodies in Yanchang Formation were controlled by the slope of the deep‐water deposits and the flows had vast distribution, huge depth and prevalent advantages for oil forming, which make it one of the most favorable new areas for Ordos Basin prospecting.
The Relation of Character Strengths to Past, Present, and Future Life Satisfaction among German‐Speaking Women
Authors: Proyer René T. , Gander Fabian , Wyss Tobias , Ruch Willibald
Published: October 2011

Background:Peterson and Seligman (2004) argue that character strengths are fulfilling and contribute to the “good life”. Building upon earlier research, this study tests the relation of strengths to past, present, and future life satisfaction.Methods:A sample of 1,087 women completed the Values in Action Inventory of Strengths and the Temporal Satisfaction with Life Scale in an online study.Results:The results suggest that primarily the strengths curiosity, hope, gratitude, love, and zest contributed to life satisfaction. Appreciation of beauty and excellence contributed more to past life satisfaction in older than in younger participants. For future life satisfaction religiousness was of importance while it was not for past or present satisfaction.Conclusions:The study underlines the importance of five key strengths that contribute to life satisfaction. It is argued that the study of the relation of character strengths with life satisfaction would greatly benefit from taking a life span perspective into account.
Laparoscopic repair of iatrogenic diaphragmatic hernia following radiofrequency ablation for hepatocellular carcinoma
Authors: Singh Mansher , Singh Gayatri , Pandey Ambarish , Cha Charles H. , Kulkarni Sanjay
Published: October 2011

Radiofrequency ablation (RFA) is commonly used for treating unresectable hepatic malignancies. Some commonly associated complications of RFA include fever, symptomatic pleural effusion, abscess, hepatoma and hepatic insufficiency. Here, we report a case of diaphragmatic hernia in a patient following RFA for hepatic malignancy with cirrhosis.
Autonomy for Ethnic Minorities in Iraq: The Chaldo‐Assyrian Case
Authors: Hanish Shak
Published: October 2011

This article discusses the issue of ethnic minorities, specifically the Chaldo‐Assyrians in Iraq. It gives a historical background, present demography, and points out group locations, mainly in Nineveh Province. It proposes a possible solution to the issue by suggesting autonomy for the group as crucial to its security and survival. It also presents a counter‐argument for autonomy. The article discusses the attitude of the Arabs and the Kurds to such proposals and compares Iraq and Kurdistan's constitutions in regard to minorities' rights. Finally, the author assesses if autonomy is a realistic approach to solve the Chaldo‐Assyrian problem in Iraq.
Just War and Terrorism: A New Policy Perspective
Authors: Stewart Kerry
Published: October 2011

The idea of terrorism as policy in any policy discussion is abhorrent in most academic circles. The fact is, however, if one removes the emotion attached to the use of terrorism and approaches it as a tool it can be placed in several models used by policymakers today. For many centuries the concept of “just war” has been discussed by philosophers, policymakers, and warriors. When standards have been established that those engaged in conflict can use to determine whether or not an action is considered “just.” How did Christianity in particular move from emphasizing love (agapē, caritas) to the acceptance of waging war? This problem was dealt with when the law of war was included in discussion of natural law theory.
β-Elemene induces apoptosis as well as protective autophagy in human non-small-cell lung cancer A549 cells
Authors: Liu Jing , Hu Xue-Jun , Jin Bo , Qu Xiu-Juan , Hou Ke-Zuo , Liu Yun-Peng
Published: October 2011

Objectives

β-Elemene, a novel traditional Chinese medicine, has been shown to be effective against a wide range of tumours. In this study, the antitumour effect of β-elemene on human non-small-cell lung cancer (NSCLC) A549 cells and the mechanism involved have been investigated.

Methods

Cell viability and apoptosis were measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively. Protein expression was assayed by Western blotting. Autophagy was evaluated under fluorescence microscopy and transmission electron microscopy.

Key findings

β-Elemene inhibited the viability of A549 cells in a dose-dependent manner. This suppression of cell viability was due to the induction of apoptosis. Further study showed that β-elemene inhibited the activity of the PI3K/Akt/mTOR/p70S6K1 signalling pathway, and at the same time it triggered a robust autophagy. The autophagy was characterized by the accumulation of punctate LC3 dots in the cytoplasm, morphological changes, and the increased levels of LC3-II as well as Atg5-Atg12 conjugated proteins. Inhibition of autophagy with chlorochine significantly enhanced the antitumour effect of β-elemene.

Conclusions

Our data indicated that β-elemene inhibited the activity of the PI3K/Akt/mTOR/p70S6K1 signalling pathway in human NSCLC A549 cells, which resulted in apoptosis as well as protective autophagy. A combination of β-elemene with autophagy inhibitor might be an effective therapeutic option for advanced NSCLC.
The crooked timber of identity: Integrating discursive, critical, and psychosocial analysis
Authors: Kaposi David
Published: October 2011

This paper seeks to contribute to the growing band of constructionist approaches within the field of identity studies (Wetherell & Moharty, 2010). First, it will review the developments that have taken place since the emergence of these approaches in the 1980s, identifying a state of fragmentation into local discursive, political‐moral, and psychosocial levels of analysis. Second, and in order to challenge this fragmentation, it will present a rhetorical psychological (Billig, 1987, 1999a) analysis of the classic exchange of public letters between Israeli historian of Judaism Gershom Scholem and American political theorist Hannah Arendt in the wake of the latter's book Eichmann in Jerusalem (Arendt, 1994a). The analysis will proceed from local discursive action, through political‐moral frameworks, to the nature of the writers’ investment in these constructions. It will show that while the participants’ implicitly occasioning of extreme identity categories (such as the ‘Jewish anti‐Semite’ and the totalitarian‐style religious Zionist ideologue) is a function of apparently incommensurable political‐moral discourses, the nature of investment into such constructions may be understood in a mutual commitment to the absolute inalienability of Jewishness. Third, therefore, the paper will conclude that, rather than constituting separate ‘levels’, local discursive action, political‐moral intelligibilities, and psychosocial qualities are mutually constitutive of each other. It is only through recognizing their inter‐dependent nature that the complexity of identity may properly be addressed.
Validation of an Infrared Extinction Method for Fuel Vapor Concentration Measurements Towards the Systematic Comparison Between Alternative and Conventional Fuels for Aviation
Authors: Fritzer Johannes , Giuliani Fabrice , Strzelecki Alain , Bodoc Virginel
Published: October 2011

Due to increasing oil prices and the obvious influence of the combustion of fossil fuel-derivatives on climate change on the one hand and the steady growth of transportation needs on the other, it is necessary to develop alternatives to oil for aviation. For this purpose a specific research program on the investigation of adequate alternative fuels for aviation has been founded by the European Commission’s Framework Program. The project Alfa Bird (Alternative Fuels and Bio-fuels in Aircraft Development) focuses on an identification of possible alternative fuels to kerosene, the investigation of the adequacy of the selected ones, an evaluation of the environmental and economic impact of them, and finally the creation of a future perspective for the industrial use of the “best” alternative. The main part of the investigation activities at TU Graz, in cooperation with ONERA Centre de Toulouse and Fauga-Mauzac on these specific topics consists of the analysis of the evaporation of the previously chosen fuel types in comparison to fully synthetic jet fuel. Therefore qualitative measurements to obtain vapor concentration gradients will be done using the infrared extinction (IRE) measurement method. Based on a simplified Beer–Bouguer–Lambert law the integral vapor concentrations can be obtained. The main hypothesis is that if the line-of-sight extinction due to Mie-scattering is similar for both infrared and visible wavelengths because of the presence of the spray, only infrared light will be absorbed by the fuel vapor, being transparent to visible light. This contribution focuses on the validation of the infrared measurement technique on a well characterized spray. The tests are performed under controlled boundary conditions. Therefore an existing IRE test arrangement at ONERA Toulouse using an ultrasonic atomizer injecting n-octane at atmospheric conditions has been analyzed. Error sources related to misalignments in the hardware have been considered and an iterative alignment method of the laser beams followed by a beam diameter and diffraction analysis have been performed. Optimizing the setup to obtain a stable operation point has been successful. Improved experimental results at this operation point were compared with existing simulation results for the evaporation of the ultrasonic atomizer used. The achieved data has shown good accordance to the existing simulation results.
Temperature induced changes in a AgPt nanofilm on Ru(0001)
Authors: Onsgaard Jens , Jan Godowski P. , Shen Li Zhe
Published: October 2011

Nanometer thick AgPt films deposited in a layer-by-layer fashion onto Ru(0001) at room temperature (RT) were investigated using high-resolution photoelectron spectroscopy. A four layer film, Pt(1)Ag(1)Pt(1)Ag(1)/Ru(0001), with one monolayer of Ag as the first deposited material on Ru(0001), shows a small intermixing of Ag and Pt during deposition at RT. The Pt4f7/2 spectra exhibit the most pronounced core level shifts during heating; an effect caused by clustering of Pt inside the film. No alloying of Ag and Pt is observed. This behavior is in contrast to that of analog AgPd films on Ru(0001) where alloying takes place. Annealing of the layered AgPt film in the temperature interval of RT to 625 °C results in the segregation of Ag at the surface and a complete desorption of Ag takes place at 625 °C.
Comparison of secondary neutron dose in proton therapy resulting from the use of a tungsten alloy MLC or a brass collimator system
Authors: Diffenderfer Eric S. , Ainsley Christopher G. , Kirk Maura L. , McDonough James E. , Maughan Richard L.
Published: October 2011

Purpose:

To apply the dual ionization chamber method for mixed radiation fields to an accurate comparison of the secondary neutron dose arising from the use of a tungsten alloy multileaf collimator (MLC) as opposed to a brass collimator system for defining the shape of a therapeutic proton field.

Methods:

Hydrogenous and nonhydrogenous ionization chambers were constructed with large volumes to enable measurements of absorbed doses below 10–4 Gy in mixed radiation fields using the dual ionization chamber method for mixed‐field dosimetry. Neutron dose measurements were made with a nominal 230 MeV proton beam incident on a closed tungsten alloy MLC and a solid brass block. The chambers were cross‐calibrated against a 60Co‐calibrated Farmer chamber in water using a 6 MV x‐ray beam and Monte Carlo simulations were performed to account for variations in ionization chamber response due to differences in secondary neutron energy spectra.

Results:

The neutron and combined proton plus γ‐ray absorbed doses are shown to be nearly equivalent downstream from either a closed tungsten alloy MLC or a solid brass block. At 10 cm downstream from the distal edge of the collimating material the neutron dose from the closed MLC was (5.3 ± 0.4) × 10− 5 Gy/Gy. The neutron dose with brass was (6.4 ± 0.7) × 10− 5 Gy/Gy. Further from the secondary neutron source, at 50 cm, the neutron doses remain close for both the MLC and brass block at (6.9 ± 0.6) × 10− 6 Gy/Gy and (6.3 ± 0.7) × 10− 6 Gy/Gy, respectively.

Conclusions:

The dual ionization chamber method is suitable for measuring secondary neutron doses resulting from proton irradiation. The results of measurements downstream from a closed tungsten alloy MLC and a brass block indicate that, even in an overly pessimistic worst‐case scenario, secondary neutron production in a tungsten alloy MLC leads to absorbed doses that are nearly equivalent to those seen from brass collimators. Therefore, the choice of tungsten alloy in constructing the leaves of a proton MLC is appropriate, and does not lead to a substantial increase in the secondary neutron dose to the patient compared to that generated in a brass collimator.
Time-Critical Social Mobilization
Authors: Pickard Galen , Pan Wei , Rahwan Iyad , Cebrian Manuel , Crane Riley , Madan Anmol , Pentland Alex
Published: October 2011

Results from a competition allow an analysis of incentives for assembling teams of unrelated people to accomplish tasks.
Images of Asteroid 21 Lutetia: A Remnant Planetesimal from the Early Solar System
Authors: Sierks H. , Lamy P. , Barbieri C. , Koschny D. , Rickman H. , Rodrigo R. , A’Hearn M. F. , Angrilli F. , Barucci M. A. , Bertaux J.-L. , Bertini I. , Besse S. , Carry B. , Cremonese G. , Da Deppo V. , Davidsson B. , Debei S. , De Cecco M. , De Leon J. , Ferri F. , Fornasier S. , Fulle M. , Hviid S. F. , Gaskell R. W. , Groussin O. , Gutierrez P. , Ip W. , Jorda L. , Kaasalainen M. , Keller H. U. , Knollenberg J. , Kramm R. , Kührt E. , Küppers M. , Lara L. , Lazzarin M. , Leyrat C. , Moreno J. J. Lopez , Magrin S. , Marchi S. , Marzari F. , Massironi M. , Michalik H. , Moissl R. , Naletto G. , Preusker F. , Sabau L. , Sabolo W. , Scholten F. , Snodgrass C. , Thomas N. , Tubiana C. , Vernazza P. , Vincent J.-B. , Wenzel K.-P. , Andert T. , Pätzold M. , Weiss B. P.
Published: October 2011

A spacecraft flyby of an asteroid reveals a high-density body that is more like a planetesimal than a rubble pile.
Preparing for Resettlement Associated with Climate Change
Authors: de Sherbinin A. , Castro M. , Gemenne F. , Cernea M. M. , Adamo S. , Fearnside P. M. , Krieger G. , Lahmani S. , Oliver-Smith A. , Pankhurst A. , Scudder T. , Singer B. , Tan Y. , Wannier G. , Boncour P. , Ehrhart C. , Hugo G. , Pandey B. , Shi G.
Published: October 2011

Mitigation and adaptation projects will lead to increased population displacement, calling for new research and attention to past lessons.
Immunization with Ehrlichia P28 Outer Membrane Proteins Confers Protection in a Mouse Model of Ehrlichiosis
Authors: Crocquet-Valdes Patricia A. , Thirumalapura Nagaraja R. , Ismail Nahed , Yu Xuejie , Saito Tais B. , Stevenson Heather L. , Pietzsch Colette A. , Thomas Sunil , Walker David H.
Published: October 2011

The obligately intracellular bacterium
Ehrlichia chaffeensis
that resides in mononuclear phagocytes is the etiologic agent of human monocytotropic ehrlichiosis (HME). HME is an emerging and often life-threatening, tick-transmitted infectious disease in the United States. Effective primary immune responses against
Ehrlichia
infection involve generation of
Ehrlichia
-specific gamma interferon (IFN-γ)-producing CD4
+
T cells and cytotoxic CD8
+
T cells, activation of macrophages by IFN-γ, and production of
Ehrlichia
-specific antibodies of the Th1 isotype. Currently, there are no vaccines available against HME. We evaluated the ability of 28-kDa outer membrane proteins (P28-OMP-1) of the closely related
Ehrlichia muris
to stimulate long-term protective memory T and B cell responses and confer protection in mice. The spleens of mice vaccinated with
E. muris
P28-9, P28-12, P28-19, or a mixture of these three P28 proteins (P28s) using a DNA prime-protein boost regimen and challenged with
E. muris
had significantly lower bacterial loads than the spleens of mock-vaccinated mice. Mice immunized with P28-9, P28-12, P28-19, or the mixture induced
Ehrlichia-
specific CD4
+
Th1 cells. Interestingly, mice immunized with P28-14, orthologs of which in
E. chaffeensis
and
E. canis
are primarily expressed in tick cells, failed to lower the ehrlichial burden in the spleen. Immunization with the recombinant P28-19 protein alone also significantly decreased the bacterial load in the spleen and liver compared to those of the controls. Our study reports, for the first time, the protective roles of the
Ehrlichia
P28-9 and P28-12 proteins in addition to confirming previous reports of the protective ability of P28-19. Partial protection induced by immunization with P28-9, P28-12, and P28-19 against
Ehrlichia
was associated with the generation of
Ehrlichia-
specific cell-mediated and humoral immune responses.
Identification and Analysis of Papillomavirus E2 Protein Binding Sites in the Human Genome
Authors: Võsa Liisi , Sudakov Aleksander , Remm Maido , Ustav Mart , Kurg Reet
Published: October 2011

Papillomavirus E2 protein is required for the replication and maintenance of viral genomes and transcriptional regulation of viral genes. E2 functions through sequence-specific binding to 12-bp DNA motifs—E2 binding sites (E2BS)—in the virus genome. Papillomaviruses are able to establish persistent infection in their host and have developed a long-term relationship with the host cell in order to guarantee the propagation of the virus. In this study, we have analyzed the occurrence and functionality of E2BSs in the human genome. Our computational analysis indicates that most E2BSs in the human genome are found in repetitive DNA regions and have G/C-rich spacer sequences. Using a chromatin immunoprecipitation approach, we show that human papillomavirus type 11 (HPV11) E2 interacts with a subset of cellular E2BSs located in active chromatin regions. Two E2 activities, sequence-specific DNA binding and interaction with cellular Brd4 protein, are important for E2 binding to consensus sites. E2 binding to cellular E2BSs has a moderate or no effect on cellular transcription. We suggest that the preference of HPV E2 proteins for E2BSs with A/T-rich spacers, which are present in the viral genomes and underrepresented in the human genome, ensures E2 binding to specific binding sites in the virus genome and may help to prevent extensive and possibly detrimental changes in cellular transcription in response to the viral protein.
A Novel Cyanophage with a Cyanobacterial Nonbleaching Protein A Gene in the Genome
Authors: Gao E-Bin , Gui Jian-Fang , Zhang Qi-Ya
Published: October 2011

A cyanophage, PaV-LD, has been isolated from harmful filamentous cyanobacterium
Planktothrix agardhii
in Lake Donghu, a shallow freshwater lake in China. Here, we present the cyanophage's genomic organization and major structural proteins. The genome is a 95,299-bp-long, linear double-stranded DNA and contains 142 potential genes. BLAST searches revealed 29 proteins of known function
in
cyanophages, cyanobacteria, or bacteria. Thirteen major structural proteins ranging in size from 27 kDa to 172 kDa were identified by SDS-PAGE and mass-spectrometric analysis. The genome lacks major genes that are necessary to the tail structure, and the tailless PaV-LD has been confirmed by an electron microscopy comparison with other tail cyanophages and phages. Phylogenetic analysis of the major capsid proteins also reveals an independent branch of PaV-LD that is quite different from other known tail cyanophages and phages. Moreover, the unique genome carries a nonbleaching protein A (NblA) gene (open reading frame [ORF]
022L
), which is present in all phycobilisome-containing organisms and mediates phycobilisome degradation. Western blot detection confirmed that
022L
was expressed after PaV-LD infection in the host filamentous cyanobacterium. In addition, its appearance was companied by a significant decline of phycocyanobilin content and a color change of the cyanobacterial cells from blue-green to yellow-green. The biological function of PaV-LD
nblA
was further confirmed by expression in a model cyanobacterium via an integration platform, by spectroscopic analysis and electron microscopy observation. The data indicate that PaV-LD is an exceptional cyanophage of filamentous cyanobacteria, and this novel cyanophage will also provide us with a new vision of the cyanophage-host interactions.
Infrared spectra of liebigite, andersonite, voglite and schroeckingerite
Authors: Urbanec Zdeněk , Čejka Jiří
Published: October 2011

Infrared spectra of mineral possessing layer structure - liebigite, Ca2[UO2(CO3)3].(8-11) H2O, schroeckingerite, NaCa3[UO2(CO3)3]SO4F.10 H2O, voglite, Ca2Cu[UO2(CO3)4].6 H2O (?), and synthetic andersonite, Na2Ca[UO2(CO3)3].6 H2O - were measured and interpreted and compared with the published infrared spectra of ammonium, potassium, rubidium, and cesium dioxo-tricarbonatouranates(VI). From the analysis of the infrared spectra it follows - in accordance with the results of X-ray diffraction analysis - that in the dioxo-tricarbonatouranate(VI) complex anion, [UO2(CO3)3]4-, forming hexagonal bipyramid, three bidentately bonded carbonate groups are present in the equatorial plane (in liebigite and andersonite and apparently also in schroeckingerite and voglite). The coordinations of the SO42- and F- ions in schroeckingerite and of the fourth carbonate group (?) in voglite have not been elucidated.
On applicability of EHT method for study of interactions of pyridinium ions with anions. Calculations of pyridine hydrochloride
Authors: Kuthan Josef , Böhm Stanislav , Skála Vratislav
Published: October 2011

EHT calculations of the ion-pair I do not give, according to what is expected, the overall energy minimum corresponding to stabilization energy of ionic bond between the both partners. However, position of local minima at some energy curves corresponds to mutual orientation of pyridinium cation and chloride anion in the crystal. Orbital symmetry and interaction between the both mentioned ions are discussed.
N(1)-methyl-2β,16β-dihydroakuammicine N(4)-methochloride and epipleiocarpamine N(4)-oxide, two new alkaloids from Vinca minor L.
Authors: Votický Zdeno , Dolejš Ladislav , Grossmann Eduard
Published: October 2011

Two new quaternary alkaloids, N(1)-methyl-2β,16β-dihydroakuammicine N(4)-methochloride and epipleiocarpamine N(4)-oxide, were isolated from the leaves of Vinca minor L. Their constitution and configuration were established on the basis of spectral evidence and correlation.
Determination of thermodynamic functions by means of infrared spectroscopy. The accuracy in -ΔH determination; Formation of complexes phenol-pyridine and its homologues
Authors: Šára Václav , Moravec Jaromír , Horák Milan
Published: October 2011

Values of thermodynamic functions -ΔH, -ΔG, and -ΔS of the complex formation between molecules of pyridine (and its methyl derivatives) and phenol in CCl4 solutions were determined using infrared spectroscopy. After optimalizing experimental conditions the error in -ΔH determination does not exceed 0.2%; this accuracy is sufficiently high to investigate the influence of substituents on the pyridinic nitrogen basicity. The values of -ΔH determined in this way correlate linearly with values of ionization constants of pyridine bases.
Participation of the methoxyl group in the cleavage of some 19-substituted steroid epoxides. A case of competition between internal and external nucleophile attack
Authors: Kočovský Pavel , Černý Václav
Published: October 2011

Acid cleavage of two steroid epoxides III and IV, bearing a methoxy group in position 19, with aqueous perchloric acid or hydrobromic acid gives two types of products, i.e. diols or bromohydrins VI, VII, IX and X as products of the normal reaction course and cyclic ethers V and VIII formed by participation of the 19-methoxy group. Discussed is similarity of these reactions with electrophilic additions to the related 19-methoxy olefins I and II, the mechanism, and the difference in behavior of both epoxides III and IV. Also discussed is the dependence of product ratios on the nucleophility of the attacking species.
Synthesis of 5-methyl-2H-1,3-oxazine-2,4(3H)-dione
Authors: Farkaš Jiří
Published: October 2011

The title compound (II) was prepared by acid-catalysed hydrolysis of N,N-disubstituted β-methoxy-α-methylacryloylureas V-VIII. This reaction is accompanied by the parallel cleavage of the amide bond in the compounds V-VII leading to N,N-disubstituted ureas and α-formylpropionic acid.
Cyclopropanes of 5-nitrofuran series
Authors: Prousek Josef , Jurášek Adolf , Dandárová Miloslava , Kováč Jaroslav
Published: October 2011

5-Nitrofurfuryl trichloromethyl sulphone (I) was reacted with paraformaldehyde in methanol in the presence of piperidine as catalyst to give 1-(5-nitro-2-furyl)-1-trichloromethylsulphonyl-2-(5-nitro-2-furyl)cyclopropane. This substance was also obtained from 1-(5-nitro-2-furyl)-1-trichloromethylsulphonyl-2-(5-nitro-2-furyl)ethylene and diazomethane. The reaction products were characterized by IR, UV, 1H NMR and mass spectral data.
Formation of silenium dication from dimethyldichlorosilane
Authors: Kučera Miloslav , Kelblerová Helena
Published: October 2011

Hydrolysis of dimethyldichlorosilane with water in the presence of HClO4 leads, under certain conditions, to the formation of a defined dication of high initiation efficiency. For the dication formation the initial mixture must contain the excess of hydrolysable Cl- over H+ from water and HClO4. It is described the course of one-step and two-step hydrolysis and the efficiency of low-pressure removal of equilibrium volatiles. The dication formed is characterized by its molecular weight and by the content of ClO4- and Cl-. Infrared and NMR spectra give the evidence that -Si-OH groups are present in the amount of less than 1% of the total Si+ClO4- groups. The initiation efficiency and the dication character of its initiator have been proved by polymerisation tests.
Synthesis of racemic and optically active erythro- and threo-9-(2,3,4-trihydroxybutyl)adenines and related compounds
Authors: Holý Antonín
Published: October 2011

Reduction of diethyl 2,3-O-isopropylidene-DL-tartrate (II) with lithium aluminium hydride afforded 2,2-dimethyl-1,3-dioxolane-threo-4,5-dimethanol (III) which was transformed to the monotosyl derivative VI. Reaction of this compound with sodium salt of adenine, followed by acidic deblocking, gave 9-(DL)-threo-(2,3,4-trihydroxybutyl)adenine (IX). Analogously, 9-(DL)-erythro-(2,3,4-trihydroxybutyl)adenine (XVII) was prepared from diethyl meso-tartrate (XI) via the diol XIII and the tosyl derivative XV. 1,3-O-Benzylidene-D-threitol (D-XVIII) was converted successively into the 4-O-tosyl derivative XIX and the 2-O-benzoyl-4-O-tosyl derivative XX. Reaction of the compound XX with sodium salt of adenine, followed by removal of the protecting groups in the intermediate XXI, afforded 9-(D)-threo-(2,3,4-trihydroxybutyl)adenine (D-XXII); analogously, 1,3-O-benzylidene-L-threitol (L-XVIII) was transformed into the 9-(L)-threo-derivative L-XXII. The D-threo-derivative D-XXII was prepared also from 5-O-tosyl-3-O-benzoyl-1,2-O-isopropylidene-α-D-xylofuranoside (XXIII) or from 3-O-benzyl derivative XXIX by condensation with sodium salt of adenine, followed by acidic hydrolysis, degradation of the 1,2-diol grouping by sodium periodate and sodium borohydride, and methanolysis or hydrogenolysis. An analogous procedure was used for preparation of 1-(D)-threo-(2,3,4-trihydroxybutyl)uracil (D-XXVII). Methyl 2,3-O-isopropylidene-5-benzoyl-6-tosyl-D-mannofuranoside (XXXVI) was transformed to the 5-(adenin-9-yl) derivative XXXVII which after hydrolysis of the dioxolane ring, followed by cleavage of the cis-diol with sodium periodate, reduction with sodium borohydride and methanolysis, afforded 9-(D)-erythro-(2,3,4-trihydroxybutyl)adenine (D-XL). The L-enantiomer (L-XL) was obtained from 5-O-(adenin-9-yl)-3-O-benzoyl-1,2-O-isopropylidene-β-L-arabinofuranoside (XXXIIIb) by acidic cleavage, degradation of the intermediate XXXIV with periodate and methanolysis.
High-speed isotachophoresis. Analytical aspects of the steady-state longitudinal temperature profiles
Authors: Ryšlavý Zbyněk , Boček Petr , Deml Miroslav , Janák Jaroslav
Published: October 2011

The problem of the longitudinal temperature distribution was solved and the bearing of the temperature profiles on the qualitative characteristics of the zones and on the interpretation of the record of the separation obtained from a universal detector was considered. Two approximative physical models were applied to the solution: in the first model, the temperature dependences of the mobilities are taken into account, the continuous character of the electric field intensity at the boundary being neglected; in the other model, the continuous character of the electric field intensity is allowed for. From a comparison of the two models it follows that in practice, the variations of the mobilities with the temperature are the principal factor affecting the shape of the temperature profiles, the assumption of a discontinuous jump of the electric field intensity at the boundary being a good approximation to the reality. It was deduced theoretically and verified experimentally that the longitudinal profiles can appreciably affect the longitudinal variation of the effective mobilities in the zone, with an infavourable influence upon the qualitative interpretation of the record. Pronounced effects can appear during the analyses of the minor components, where in the corresponding short zone a temperature distribution occurs due to the influence of the temperatures of the neighbouring zones such that the temperature in the zone of interest in fact does not attain a constant value in axial direction. The minor component does not possess the steady-state mobility throughout the zone, which makes the identification of the zone rather difficult.
Contribution to study of π-electronic effects in monosubstituted benzenes
Authors: Danihel Ivan , Kuthan Josef
Published: October 2011

π-Electronic densities in a series of monosubstituted benzenes I calculated by the PPP method are discussed in relation to the substitution effect of substituent X, to σR0 or σ parameters and to chemical shifts in NMR spectra. π-Electronic characteristics of the compounds I are confronted with electronic and photoelectronic spectra.
The conformation of substituted hydroxyureas and hydroxythioureas in solution
Authors: Mollin Jiří , Fiedler Pavel , Jehlička Václav , Exner Otto
Published: October 2011

The conformation of 1,3-disubstituted 1-hydroxyureas Ia-d and 1-hydroxythioureas IIa-d, mostly with aromatic substituents, was investigated by means of dipole moments in dioxan solution and by infrared spectroscopy. The results are concordant for the two classes of compounds. The most populated conformation is near to the planar Z, E, ap form (A), or possibly with the hydroxyl hydrogen out of the N-C-N-O plane (between A and B). This finding from the analysis of dipole moments is corroborated by the presence of the amide-II band and absence of intramolecular hydrogen bonds. While the conformation of hydroxyureas seems to be virtually uniform, in the case of hydroxythioureas a less abundant rotamer may be present in nonpolar solvents, possibly the E, E, sp (G) or E, E, ap (F) form. The conformation found (A) is not explicable in terms of hydrogen bonds and/or steric factors when compared to symmetrically substituted ureas (thioureas) and to N-alkylhydroxamic acids.
Synthesis, spectral properties and pesticidal activity of some O-(2,4,5-trichloro-6-bromo/iodo, nitro/phenyl) esters of carbamic and thiocarbamic acids
Authors: Konečný Václav , Varkonda Štefan , Kulíčková Naďa
Published: October 2011

2,4,5-Trichloro-6-bromo/iodo, nitro/phenyl carbamates have been prepared by reaction of 2,4,5-trichloro-6-bromo/iodo, nitro/phenyl chlorocarbonates with amines or by reaction of carbamoyl chloride with sodium 2,4,5-trichloro-6-bromo/iodo, nitro/phenolate, and the thiocarbamate esters have been prepared by reaction of O-(2,4,5-trichloro-6-bromo/iodo, nitro/phenyl) ester of chlorothiocarbonic acid with amines. IR and UV spectra of the synthetized compounds have been interpreted. The compounds have been tested for contact and systeme insecticidal, acaricidal, ovicidal, fungicidal and herbicidal activity. The highest fungicidal activity has been observed against powdery mildew disease.
Some 6-substituted derivatives of D-8-cyanomethylergoline-I and D-8-methylergoline-I
Authors: Černý Antonín , Křepelka Jiří , Semonský Miroslav
Published: October 2011

Compounds III-XX exhibiting antilactation and antinidation effects in tests on rats were prepared on N(6)-alkylation of D-8-cyanomethylergoline-I (I) or D-8-methylergoline-I (II) with corresponding bromo (chloro) derivatives in dimethylformamide. The most distinct prolactin-inhibiting activity was found in compound III.
Porous electrodes for the preparation of peroxide by reduction of oxygen; Influence of the content of polyethylene
Authors: Špalek Otomar
Published: October 2011

With porous electrodes prepared by pressing a mixture of carbon black and polyethylene powder, the influence of the content of the binder on their electric resistance, wettability, current density, and current yield of peroxide during reduction of oxygen was studied.
Modified factor analysis of the circular dichroism spectra, applied to a series of cyclodipeptides containing L-proline
Authors: Pančoška Petr , Frič Ivo , Bláha Karel
Published: October 2011

A mathematical model has been developed which uses the theory of Hilbert spaces and the modified method of the principal components of the factor analysis to the determination of the minimum number of subspectra sufficient to describe a set of experimental CD curves of a series of structurally related compounds. The use of this method has been demonstrated on the CD spectra of nine cyclodipeptides containing (besides L-proline) glycine, L or D alanine, L or D valine, L or D leucine, and L or D tert-leucine, measured in acetonitrile and 2,2,2-trifluoroethanol. Relation is discussed between the calculated subspectra and the structural characteristics of the measured systems.
Statistical accuracy test in measurements of circular dichroism
Authors: Pančoška Petr , Frič Ivo , Bláha Karel
Published: October 2011

A collection of one hundred circular dichroism measurements (in acetonitrile) of the model cyclohexapeptide cyclo(glycyl-L-phenylalanyl-L-leucyl-glycyl-L-leucyl-L-phenylalanyl) has been evaluated using standard statistical methods. The reproducibility of the experimental intensity values is discussed with respect to the sample concentration and the particular regions of the CD curve. The maximum probable error in the intensity reading varies with wavelength from ±20 to ±10 000 deg cm2 dmol-1 in the spectral range from 274 to 196 nm, i.e. by 5-15% of the observed intensity.
Synthesis of 3,5-disubstituted 1,2,4-triazole derivatives - An alternative preparation of the C-analogue of ribavirin
Authors: Vaněk Tomáš , Farkaš Jiří , Gut Jiří
Published: October 2011

Condensation of ethyl acetothioimidate hydrochloride (III) with amidrazones IV afforded 3-methyl-5-phenyl-1,2,4-triazole (Va) and ethyl 3-methyl-1,2,4-triazole-5-carboxylate (Vb). Analogously, the thioimidate hydrochloride VI was transformed into ethyl 5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-1,2,4-triazole-3-carboxylate (VIIa) which, after removal of benzoyl groups, was ammonolysed to the amide II.
Synthesis of 5-β-D-ribofuranosyl-1,3-thiazole-2-carboxamide - A thiazole analogue of ribavirin
Authors: Vaněk Tomáš , Farkaš Jiří , Gut Jiří
Published: October 2011

Condensation of ethyl thioxamate (II) with bromomethyl D-ribo-1,2,3,4-tetraacetoxybutyl ketone (I) or bromomethyl 2,3,5-tri-O-benzoyl-β-D-ribofuranosyl ketone (IX) afforded ethyl 5-(D-ribo-1,2,3,4-tetraacetoxybutyl)-1,3-thiazole-2-carboxylate (III) and ethyl 5-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-1,3-thiazole-2-carboxylate (X), respectively. Removal of the protecting groups and ammonolysis of the ester gave the respective 5-(D-ribo-1,2,3,4-tetrahydroxybutyl)-1,3-thiazole-2-carboxamide (V) and 5-(β-D-ribofuranosyl)-1,3-thiazole-2-carboxamide (XI).
Study of chromium(II) phosphites
Authors: Kavan Ladislav , Ebert Miroslav
Published: October 2011

Chromium(II) phosphites CrHPO3.H2O, CrDPO3.2 D2O, CrH4P2O6.H2O and CrD4P2O6.D2O were studied in the solid state by powder X-ray diffraction, thermography, electronic reflection spectroscopy, magnetic susceptibility measurements, and Raman and infrared absorption spectroscopy. The phosphite CrHPO3.H2O involves an anion whose point symmetry is reduced from C3v to Cs. The vibrational spectra of the phosphite CrDPO3.2 D2O were discussed in terms of the correlation and factor group approach. Chromium(II) dihydrogenbis(orthophosphite) involves in the crystal lattice two hydrogen bonds, lengths 269 ± 2 pm and 286 ± 2 pm. The stronger hydrogen bonding is originated on the interaction of an oxygen atom and a hydroxyl group bonded at two different phosphorus atoms, and brings about among others a lowering of the crystal field strength in the hydrogenphosphite. The weaker hydrogen bond is probably formed between the anion and the water molecule.
Reactions of 1-substituted 2,4,6-trinitrobenzenes with nucleophiles
Authors: Kaválek Jaromír , Ashfaq Ahmad , Štěrba Vojeslav
Published: October 2011

Rate constants have been determined of nucleophilic aromatic substitution of 2,4,6-trinitrophenyl methyl ether (Ia), 2,4,6-trinitrophenyl ethanoate (Ic), 2,4,6-trinitrochlorobenzene (Ib), 2,4,6-trinitrodiphenyl ether (Id), 2,4,6-trinitro-4'-bromodiphenyl ether (Ie), 2,3',4,6-tetranitrodiphenyl ether (If) and 2,4,4',6-tetranitrodiphenyl ether (Ig) with methoxide, ethanoate and methyl cyanoethanoate (II) anions in methanol. For the compounds Ia,b rate and equilibrium constants of addition of the anion II(-) at positions 3 and 5 have been measured, too. In reactions of the compounds Ia to Ig with ethanoate anion the first (rate-limiting) step produces the phenyl ester Ic which reacts with a further ethanoate anion to give 2,4,6-trinitrophenol (Ih) and ethanoic anhydride. In reactions of the bromo derivative Ie and, to a still larger extent, compound Id the methyl derivative Ia is formed besides the compound Ih.
Untersuchung der Reaktion von Arsen(III)-fluorid mit Selentrioxid
Authors: Toužín Jiří , Mezník Lubomír , Mitáček Lubomír
Published: October 2011

Bei der Reaktion von Arsen(III)-fluorid mit Selentrioxid im Medium von flussigem Schwefeldioxid und auch in Abwesenheit eines inerten Losungsmittels entstehen Difluoride der Oligoselensauren, deren Menge und Polymerisationsstufe vom Molverhaltnis der reagierenden Komponenten abhangig ist. Beim flussigen Reaktionsprodukt handelt es sich um ein Gemisch oligomerer und polymerer Molekule, in deren Ketten die Arsen- und Selenatome mittels Sauerstoffbrucken gegenseitig gebunden sind.
Electrochemical behaviour and ESR spectra of nitro substituted mono- and dibenzoylmethylenebenzthiazolines and selenazolines
Authors: Komenda Jaro , Huzlík Jiří
Published: October 2011

Compounds of the type of 2-(4'-nitrobenzoyl)methylene-3-ethylbenzothiazoline (I) and 2-bis-(p-nitrobenzoyl)methylene-3-ethylbenzothiazoline (II) were studied polarographically and by ESR spectroscopy to obtain informations about their electrochemical and follow-up reactions and their conformation. Whereas with compounds of the type I the conjugation in their molecules is preserved, with type II the coplanarity of the molecules is disturbed, which is manifested in the values of the splitting constants of the ESR spectra and a slow electron transfer between both nitrophenyl substituents. These conclusions are supported by NMR spectroscopic studies.
The inhibitory effects of some adenosine nucleolipids on the lipolysis in rat epididymal fat pads in vitro
Authors: Hynie Sixtus , Smrt Jiří
Published: October 2011

3'-Oleolyl-2,3-dihydroxypropyl-AMP, 3'-stearoyl-2,3-dihydroxypropyl-AMP, octadecyl-AMP and palmitamidoethyl-AMP inhibited in comparison with adenosine or fatty acids much stronger the lipolysis in rat epididymal fat pads in vitro stimulated by isoproterenol, theophylline and dibutyryl cyclic AMP. The inhibition of the effects of the two latter drugs suggest that the described effect is caused not only by the inhibition of the cyclic AMP production but also by the inhibition of its effect on the following steps in process of lipolysis.
Hydrogenation derivatives of rifampicin; Their tritium labelling
Authors: Hanuš Jan , Kozel Jaroslav , Beneš Josef , Sedmera Petr
Published: October 2011

The structures of four rifampicin derivatives obtained by its catalytic hydrogenation were determined by mass and 1H NMR spectroscopy. These are 16,17- and 18,19-dihydrorifampicin, its Δ17,18-isomer and 16,17,18,19-tetrahydrorifampicin. The Δ18,19- and Δ17,18-rifampicins were labelled by tritium.
Reactions of ethyl 2-(nitrophenyl)-4H-furo[3,2-b]pyrrole-5-carboxylate
Authors: Krutošíková Alžbeta , Kováč Jaroslav , Dandárová Miloslava , Veverka Miroslav
Published: October 2011

Reactions of ethyl 2-(2-nitrophenyl)-4H-furo[3,2-b]pyrrole-5-carboxylate were studied. The preparation of a new heterocyclic system -pyrrolo[2',3' : 4,5]furo[3,2-b]indole- is described.
1H NMR spectra and the conformation of 1,6 : 2,3- and 1,6 : 3,4-dianhydro-β-D-hexopyranoses and their derivatives
Authors: Buděšínský Miloš , Černý Miloslav , Trnka Tomáš , Vašíčková Soňa
Published: October 2011

The 1H NMR spectra of 1,6 : 2,3- and 1,6 : 3,4-dianhydro-β-D-hexopyranoses and their acetyl-, trichloroacetylcarbamoyl- and 2- or 4-deoxy derivatives were measured in hexadeuteriodimethyl sulfoxide or deuteriochloroform. In these solvents dianhydro derivatives assume the half-chair conformations 5H0 or 1H0 which are not distinctly affected by the presence of substituents. The effects of substituents on the chemical shifts and the adjusted relation for the dependence of the vicinal coupling constants on the torsion angle are discussed from the point of view of conformation and the interactions of the oxirane ring with the oxygen O(5) and O(6) of the 1,6-anhydropyranose skeleton. Intramolecular hydrogen bonds in free dianhydrohexopyranoses were measured and identified in tetrachloromethane solution.
Extraction of iron, cobalt, nickel and copper with dibenzyl sulfoxide solution in toluene
Authors: Vláčil František , Khanh Huynh Dang
Published: October 2011

The dependence of the distribution ratio of the metal on the concentration of hydrochloric of nitric acid was examined for Fe, Co, Ni and Cu extraction with 0.05M solution of dibenzylsulfoxide in toluene. Iron is extracted considerably more than the other metals, and is better extracted from hydrochloric acid than from nitric acid. The separation factor αFe/M (for 8M-HCl) is of the order of 104; this is not sufficient for a separation of trace quantities of iron from Co, Ni and Cu, but even at lower concentrations of HCl (e.g., 5M) the values is high enough for extraction chromatographic separation. The composition of the iron solvate extracted from HCl or LiCl medium was determined to be HFeCl4.2 B (B = dibenzyl sulfoxide).