bluuebunny/crossref_metadata_2025 huggingface dataset:
Politics as a Vocation—Praxis and Political Engagement
Authors: Kaufman Robert M.
Published: April 2006

Were one to ask the typical, sophisticated American voter what it is that political scientists do, he or she might respond, “Why, they study politics!” Were one to ask the same of the somewhat more sophisticated congressional or campaign staffer, a likely response would be, “they study politics in the abstract,” accompanied by a faintly condescending smile. Lastly, were one to pose the question to the rather more sophisticated subject of this inquiry, the political science practitioner, among the range of amorphous, if not conflicting, responses one might expect would be the following: “We study the how and why of politics, the exercise of power, the underlying patterns and contexts of political and governmental behavior.” Truth, like beauty, lies in the eye of the beholder.

The following contributions, from significant scholar/practitioners, are characterized by an abiding realism as to the hazards of crossing the line, of venturing beyond the tower, towards the enchanted forest of politics. They are marked by an awareness of the distinctiveness of the two life worlds, of knowledge and power, heirs to a reflective tradition traceable to the Platonic Epistles, Hume, Weber (above all), the Frankfurt School, and Foucault. They stand in a line of intellectual activism, from Plato's tutelage of Dionysius to the examples of Sartre, Camus, Malraux, or of Vargas Llosa and Havel in our day.
Traditional Singing Style of the Lapps
Authors: Szomjas-Schiffert György
Published: April 2006

During the month of June, 1966, I undertook a folksong collecting trip among the nomadic Lapps, visiting among others the village Nunnanen in northern Finland situated more than two hundred kilometers beyond the Arctic Circle. The well-to-do Lapps of the village, all of whom have completed four to six forms of Finnish primary school, own three thousand reindeer. Throughout the summer they live with their families in tents and follow the herd, whereas in the winter they live in villages in log houses, which were rebuilt after the Second World War. Thanks to the Finnish Ministry of Culture, I was provided with an interpreter and a battery-operated tape recorder, with which we were able to collect two-hundred-and-fifty Lapp folksongs, the so-called yoiks, among reindeer farmers and shepherds. An additional twenty-six folksongs were collected orally.
Two-Part Singing From the Razlog District of Southwestern Bulgaria
Authors: Markoff Irene
Published: April 2006

Two-part singing, based predominantly on the drone type of polyphony, is a phenomenon which is still common in the Razlog district of Bulgaria. Ritual songs such as those for St. Lazarus’ Day, St. George's Day, and Easter, rain-begging, dance songs, and harvest songs are all well preserved though rarely performed, and are representative of what is known as the “old style” of singing. This type of singing is performed mainly by older women, recreating from the past songs which they once sang as young women and girls. Characteristic are narrow-range melodies commonly based on the following scale formations: ABC, ABCD, ABCDE, with or without the subtonic G, a major second below the tonic A, which ends all melodies in the collection (the melodies have been transposed for comparative purposes). Also characteristic are the traditional, harsh-sounding parallel majoren oinor seconds. Alongside this older style exists a “new style” of part singing which to a certain extent is limited to younger women. Melodies in the “new style” have a larger ambitus, with the range formulas 1-6, VII-6, 1-7, and VII-7. Although the younger women are relatively familiar with the older style and sometimes condescend to use it, they seem to prefer the modern style, in which the melodic range is less restricted and more consonant-sounding intervals are used.
Aspects of Bulgarian Musical Thought
Authors: Rice Timothy
Published: April 2006

Folk musicians are generally assumed to make music but not to think very much about it. Yet recent studies by Zemp (1978, 1979) and others demonstrate the existence of elaborate conceptual systems related to music in cultures without a written tradition. If the comparison between Western and a particular non-Western music theory seems invidious, it is partly because the West has a tradition of discourse about music (musica theoretica) that has existed for over 2000 years quite apart from practical music making (musica practica).
Acculturation in the Eskimo Songs of the Greenlanders
Authors: Olsen Poul Rovsing
Published: April 2006

The traditional Eskimo music of Greenland has long since disappeared on the greater part of the west coast, but it still survives — though in an agonizing state — in East Greenland and North Greenland. These last named places of the Arctic island have been difficult of access and have consequently been submitted to a colonial or quasi-colonial status only at a late date.
Synthesis of Substituted Benzylamino‐ and Heterocyclylmethylamino Carbodithioate Derivatives of 4‐(3H)‐Quinazolinone and their Cytotoxic Activity
Authors: Cao Sheng‐Li , Feng Yu‐Ping , Zheng Xiao‐Lin , Jiang Yu‐Yang , Zhang Mei , Wang Yue , Xu Meng
Published: April 2006

A new series of substituted benzylamino‐ and heterocyclylmethylamino carbodithioate derivatives of 4‐(3H)‐quinazolinone were synthesized via four steps starting from 2‐amino‐5‐methylbenzoic acid and initially screened against A‐549 (human non‐small cell lung cancer), HCT‐8 (human colon cancer), and Bel‐7402 (human liver cancer) cell lines at the single concentration of 5 μg/mL using the colorimetric MTT assay. The IC50 values were determined for the compounds reaching ⪈70% inhibition in primary screening by serial dilution. Among the newly synthesized compounds, 9n exhibited potent in vitro cytotoxicity against A‐549, HCT‐8, and Bel‐7402 cell lines with the IC50 values of 1.65, 0.93, and 1.43 μM, respectively.
Occupational magnetic field exposure and melatonin: Interaction with light‐at‐night
Authors: Juutilainen Jukka , Kumlin Timo
Published: April 2006

The evidence of magnetic field (MF) effects on melatonin production in humans is limited and inconsistent. Part of the inconsistencies might be explained by findings suggesting interaction with light in pineal responses to MFs. To test this hypothesis, we reanalyzed data from a previously published study on 6‐hydroxy melatonin sulfate (6‐OHMS) excretion in women occupationally exposed to extremely low‐frequency MFs. Based on questionnaire data on exposure to light‐at‐night (LAN), and measurement‐based MF data, the 60 women were classified to four groups: no MF, no LAN; MF, no LAN; no MF, LAN; MF, LAN. The lowest excretion of 6‐OHMS was observed in the group of women who were exposed to both MF and LAN, and the differences between the four groups were significant (P < .0001). The result is based on low numbers, but supports the hypothesis that daytime occupational exposure to MF enhances the effects of nighttime light exposure on melatonin production. Bioelectromagnetics 27:423–426, 2006. © 2006 Wiley‐Liss, Inc.
Analysis of Longitudinal Multinomial Outcome Data
Authors: Li Yen‐Peng , Chan Wenyaw
Published: April 2006

Analysis of categorical outcomes in a longitudinal study has been an important statistical issue. Continuous outcome in a similar study design is commonly handled by the mixed effects model. The longitudinal binary or Poisson‐like outcome analysis is often handled by the generalized estimation equation (GEE) method. Neither method is appropriate for analyzing a multinomial outcome in a longitudinal study, although the cross‐sectional multinomial outcome is often analyzed by generalized linear models. One reason that these methods are not used is that the correlation structure of two multinomial variables can not be easily specified. In addition, methods that rely upon GEE or mixed effects models are unsuitable in instances when the focus of a longitudinal study is on the rate of moving from one category to another. In this research, a longitudinal model that has three categories in the outcome variable will be examined. A continuous‐time Markov chain model will be used to examine the transition from one category to another. This model permits an unbalanced number of measurements collected on individuals and an uneven duration between pairs of consecutive measurements. In this study, the explicit expression for the transition probability is derived that provides an algebraic form of the likelihood function and hence allows the implementation of the maximum likelihood method. Using this approach, the instantaneous transition rate that is assumed to be a function of the linear combination of independent variables can be estimated. For a comparison between two groups, the odds ratios of occurrence at a particular category and their confidence intervals can be calculated. Empirical studies will be performed to compare the goodness of fit of the proposed method with other available methods. An example will also be used to demonstrate the application of this method. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Copper(II) Complexes of the Tetraazamacrocyclic Tertiary Amide Ligand Alanyl‐Cyclam
Authors: Schickaneder Christian , Heinemann Frank W. , Alsfasser Ralf
Published: April 2006

Hydrogen bonding to the electrically neutral tertiary carboxamide nitrogen atom of peptidyl‐prolyl groups is known to facilitate the C–N bond rotation during peptide and protein folding. Since metal complexes with nitrogen‐coordinated tertiary amide ligands are formally analogous, they may be used to model this so‐called electrophilic activation. In this paper we report on the synthesis of a monoacylated cyclam complex, [(Boc‐Ala‐cyclam)Cu](CF3SO3)2 (8; Boc: tert‐butyloxycarbonyl, Ala: alanine, cyclam: 1,4,8,11‐tetraazacyclotetradecane). It contains a fully sp3‐hybridized metal‐bound amide nitrogen atom. The resonance is completely cancelled and the observed C–N distance of 147 pm is consistent with a single bond. These features are exceptional among Werner‐type complexes and define the maximal possible electrophilic distortion of an amide bond.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
The Relationship Between Aromaticity and Charge‐Transfer Transitions: A Combined Study of Square‐Planar Metal Complexes Based on DFT, NMR and Nucleus‐Independent Chemical Shifts
Authors: Makedonas Christodoulos , Mitsopoulou Christiana A.
Published: April 2006

The aromaticity of square‐planar metal complexes, in this case mixed diiminodithiolate complexes of group VIII metals, has been investigated by 1H and 1H‐15N NMR spectroscopy, both experimentally and theoretically, as well as NICS indices. The electron‐donating/‐attracting ability of the substituent group and the metal ion interact with each other and control the aromaticity of the chelated rings and, as a consequence, the extent of the delocalization in the molecular plane. Evolution of the nucleus‐independent chemical shift (NICS) of the ligands upon complexation is consistent with the change in their electron distribution. At the same time, and in analogy with the EMF in closed circuits, a positive difference of the NICS value (ΔNICS) between two points (where HOMO and LUMO are located) can be envisioned as the driving force for charge‐transfer transitions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
New Reagent for Convenient Access to the α,β‐UnsaturatedN‐Methoxy‐N‐methyl‐amide Functionality by a Synthesis Based on the Julia Olefination Protocol
Authors: Narayana Manjunath Beedimane , Sane Neeraj P. , Singh Aidhen Indrapal
Published: April 2006

A new reagent for the synthesis of the α,β‐unsaturatedN‐methoxy‐N‐methyl‐amide structural unit has been developed. 2‐(Benzo[d]thiazol‐2‐ylsulfonyl)‐N‐methoxy‐N‐methylacetamide, a crystalline solid with an indefinite shelf life that can be easily prepared in two convenient steps from 2‐chloro‐N‐methoxy‐N‐methylacetamide, reacted with a variety of aldehydes under Julia conditions to furnish the α,β‐unsaturatedN‐methoxy‐N‐methyl‐amide functionality. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Analysis of jitter due to call‐level fluctuations
Authors: Mandjes Michel
Published: April 2006

In communication networks used by constant bit rate applications, call‐level dynamics (i.e. entering and leaving calls) lead to fluctuations in the load, and therefore also fluctuations in the delay (‘jitter’). By intentionally delaying the packets at the destination, one can transform the ‘perturbed’ packet stream back into the original periodic stream; in other words: there is a trade off between jitter and delay, in that jitter can be removed at the expense of delay. As a consequence, for streaming applications for which the packet delay should remain below some predefined threshold, it is desirable that the jitter remains small.

This paper presents a set of procedures to compute the jitter due to call‐level variations. We consider a network resource shared by a fluctuating set of constant bit rate applications (modelled as periodic sources). As a first step, we study the call‐level dynamics: supposing that a tagged call seesn0calls when entering the system, then we compute the probability that at the end of its duration (consisting of, say,ipackets)nicalls are present, of whichn0,istem from the originaln0calls. As a second step, we show how to compute the jitter, for givenn0,ni, andn0,i; in this analysis generalised Ballot‐problems have to be solved. We find an iterative exact solution to these, and explicit approximations and bounds. Then, as a final step, the (packet‐level) results of the second step are weighed with the (call‐level) probabilities of the first step, thus resulting in the probability distribution of the jitter experienced within the call duration. An explicit Gaussian approximation is proposed. Extensive numerical experiments validate the accuracy of the approximations and bounds. Copyright © 2006 AEIT
Performance indicator for DMT systems with non perfect channel estimation
Authors: Bueche D. , Corlay P. , Gazalet M. G. , Coudoux F. X. , Slachciak M.
Published: April 2006

In this letter, we analyse the bit error rate (BER) of a discrete multitone modulation system considering the channel estimation error for the frequency equalisation. After having established an approximate relation for the BER, we propose a simple performance indicator, which accounts for the channel estimation error, the power emitted and the noise level. In order to check the validity of the indicator, simulation has been performed. The results prove that it is more adapted to discrete multi‐tone modulation (DMT) systems than the classical mean squared channel estimation error (MSE), above all when the channel additive noise is coloured. Copyright © 2006 AEIT
A new MAP‐based channel estimation technique for multiple input multiple output diversity schemes
Authors: Hoteit Wajih , Shayan Yousef R. , Elhakeem Ahmed K.
Published: April 2006

This paper presents a channel estimation technique amenable to space‐time coding (STC). An array of transmission antennas operates in band‐limited channels with intersymbol interference. The effectiveness of STC schemes requires the development of practical and high‐performance algorithms for channel estimation. The channel parameters, to be estimated at the reception antennas, are the attenuations and delays incurred by the signals transversal along the different propagation paths. The estimation technique is based on an iterative procedure derived through the maximuma posterioriprobability (MAP) approach. Unlike classic estimation techniques, we iterate on the different probabilities of different coefficients rather than the coefficient values themselves. Two practical approaches are proposed, which are simplified versions of the general approach to implement the derived expressions required to estimate the actual channel coefficients. The performance of the two proposed algorithms has been assessed by simulation. Combined analysis/simulation results are presented and compared against those of conventional channel estimation techniques. Simulation results show that the required performance can be achieved with fewer number of iterations compared to conventional techniques. Copyright © 2006 AEIT
Inversion of heterogeneous parabolic‐type equations using the pilot points method
Authors: Alcolea Andrés , Carrera Jesús , Medina Agustín
Published: April 2006

The inverse problem (also referred to as parameter estimation) consists of evaluating the medium properties ruling the behaviour of a given equation from direct measurements of those properties and of the dependent state variables. The problem becomes ill‐posed when the properties vary spatially in an unknown manner, which is often the case when modelling natural processes. A possibility to fight this problem consists of performing stochastic conditional simulations. That is, instead of seeking a single solution (conditional estimation), one obtains an ensemble of fields, all of which honour the small scale variability (high frequency fluctuations) and direct measurements. The high frequency component of the field is different from one simulation to another, but a fixed component for all of them. Measurements of the dependent state variables are honoured by framing simulation as an inverse problem, where both model fit and parameter plausibility are maximized with respect to the coefficients of the basis functions (pilot point values). These coefficients (model parameters) are used for parameterizing the large scale variability patterns. The pilot points method, which is often used in hydrogeology, uses the kriging weights as basis functions. The performance of the method (both its variants of conditional estimation/simulation) is tested on a synthetic example using a parabolic‐type equation. Results show that including the plausibility term improves the identification of the spatial variability of the unknown field function and that the weight assigned to the plausibility term does lead to optimal results both for conditional estimation and for stochastic simulations. Copyright © 2006 John Wiley & Sons, Ltd.
Electromagnetic scattering simulation using an H(curl) conforming hp finite element method in three dimensions
Authors: Ledger P. D. , Morgan K. , Hassan O.
Published: April 2006

This work describes an approach to solving electromagnetic scattering problems in three dimensions using arbitrary order tetrahedral H(curl) conforming finite elements. We use geometric refinement of the grid to isolate the effect of singularities and use non‐uniform polynomial degree to reduce the number of unknowns. Initial distributions of the polynomial degree are generated automatically through the use of a dispersion relationship. The large complex linear system is solved efficiently by using a parallel linear equation solver. Both bistatic and monostatic scattering examples are presented to demonstrate the capabilities of the approach. Copyright © 2006 John Wiley & Sons, Ltd.
Properties and Performance of SOFCs Produced on a Pre‐Pilot Plant Scale
Authors: Hagen A. , Menon M. , Barfod R. , Hendriksen P. V. , Ramousse S. , Larsen P. H.
Published: April 2006

In the present paper, anode supported solid oxide fuel cells (SOFCs), produced on a pre‐pilot plant scale in ten batches of ∼100 cells, are characterised with respect to performance. The main purpose was to evaluate the reproducibility of the scaled‐up process. Based on 20 tests, the average area specific cell resistance at 850 °C was found to be 0.24 Ω cm2 with a standard deviation of 0.05 Ω cm2. The variation in performance between the cells can be largely attributed to variations in the cathode performance. Experimental evidence will be presented on full 4 × 4 cm2 cells, symmetric cells with two cathodes on a YSZ strip, and a special cell with a divided cathode.
How do changes in monetary policy affect bank lending? An analysis of Austrian bank data
Authors: Frühwirth‐Schnatter Sylvia , Kaufmann Sylvia
Published: April 2006

Using a panel of Austrian bank data we show that the lending decisions of the smallest banks are more sensitive to interest rate changes, and that for all banks, sensitivity changes over time. We propose to estimate the groups of banks that display similar lending reactions by means of a group indicator which, after estimation, indicates each bank's classification. Additionally, we estimate a state indicator that indicates the periods during which the lending reaction differs from what we normally observe. Bayesian methods are used for estimation; a sensitivity analysis and a forecast evaluation confirm our model choice. Copyright © 2006 John Wiley & Sons, Ltd.
Normal mixture GARCH(1,1): applications to exchange rate modelling
Authors: Alexander Carol , Lazar Emese
Published: April 2006

Some recent specifications for GARCH error processes explicitly assume a conditional variance that is generated by a mixture of normal components, albeit with some parameter restrictions. This paper analyses the general normal mixture GARCH(1,1) model which can capture time variation in both conditional skewness and kurtosis. A main focus of the paper is to provide evidence that, for modelling exchange rates, generalized two‐component normal mixture GARCH(1,1) models perform better than those with three or more components, and better than symmetric and skewed Student'st‐GARCH models. In addition to the extensive empirical results based on simulation and on historical data on three US dollar foreign exchange rates (British pound, euro and Japanese yen), we derive: expressions for the conditional and unconditional moments of all models; parameter conditions to ensure that the second and fourth conditional and unconditional moments are positive and finite; and analytic derivatives for the maximum likelihood estimation of the model parameters and standard errors of the estimates. Copyright © 2006 John Wiley & Sons, Ltd.
Cannabis, cocaine and jobs
Authors: van Ours Jan C.
Published: April 2006

This paper uses a dataset collected among inhabitants of Amsterdam, to study the employment effects of the use of cannabis and cocaine. For females no negative effects of drug use on the employment rate are found. For males there is a negative correlation between past cannabis and cocaine use and employment. However, after correcting for the effect of unobserved personal characteristics there is no negative effect of cannabis use or cocaine use on the employment status of males. Copyright © 2006 John Wiley & Sons, Ltd.
PAI‐1 transcriptional regulation during the G0 → G1 transition in human epidermal keratinocytes
Authors: Qi Li , Allen Rosalie R. , Lu Qi , Higgins Craig E. , Garone Rosemarie , Staiano‐Coico Lisa , Higgins Paul J.
Published: April 2006

Plasminogen activator inhibitor type‐1 (PAI‐1) is the major negative regulator of the plasmin‐dependent pericellular proteolytic cascade. PAI‐1 gene expression is normally growth state regulated but frequently elevated in chronic fibroproliferative and neoplastic diseases affecting both stromal restructuring and cellular migratory activities. Kinetic modeling of cell cycle transit in synchronized human keratinocytes (HaCaT cells) indicated that PAI‐1 transcription occurred early after serum stimulation of quiescent (G0) cells and prior to entry into a cycling G1 condition. PAI‐1 repression (in G0) was associated with upstream stimulatory factor‐1 (USF‐1) occupancy of two consensus E box motifs (5′‐CACGTG‐3′) at the PE1 and PE2 domains in the PF1 region (nucleotides −794 to −532) of the PAI‐1 promoter. Chromatin immunoprecipitation (ChIP) analysis established that the PE1 and PE2 site E boxes were occupied by USF‐1 in quiescent cells and by USF‐2 in serum‐activated, PAI‐1‐expressing keratinocytes. This reciprocal and growth state‐dependent residence of USF family members (USF‐1 vs. USF‐2) at PE1/PE2 region chromatin characterized the G0 → G1 transition period and the transcriptional status of the PAI‐1 gene. A consensus E box motif was required for USF/E box interactions, as a CG → AT substitution at the two central nucleotides inhibited formation of USF/probe complexes. The 5′ flanking sites (AAT or AGAC) in the PE2 segment were not necessary for USF binding. USF recognition of the PE1/PE2 region E box sites required phosphorylation with several potential involved residues, including T153, maping to the USF‐specific region (USR). A T153A substitution in USF‐1 did not repress serum‐induced PAI‐1 expression whereas the T153D mutant was an effective suppressor. As anticipated from the ChIP results, transfection of wild‐type USF‐2 failed to inhibit PAI‐1 induction. Collectively, these data suggest that USF family members are important regulators of PAI‐1 gene control during serum‐stimulated recruitment of quiescent human epithelial cells into the growth cycle. J. Cell. Biochem. 99: 495–507, 2006. © 2006 Wiley‐Liss, Inc.
The heterogeneous decomposition of ozone on atmospheric mineral dust surrogates at ambient temperature
Authors: Karagulian Federico , Rossi Michel J.
Published: April 2006

The rate of uptake of ozone on various mineral dust surrogates, expressed as uptake coefficient γ, has been studied employing a Knudsen flow reactor. Experiments were performed at T = 298 ± 2 K on substrates of kaolinite, CaCO3, natural limestone, Saharan dust, and Arizona test dust. Initially, the uptake coefficients have been calculated on the basis of the geometric surface area of the powder samples. Both initial and steady‐state uptake coefficients γ0 and γss were found very similar for all the examined substrates. In addition, additional uptake experiments on marble sample have shown that γ0 and γss may be overestimated between a factor of 50 and 100, respectively. Based on these considerations, we proposed initial and steady‐state uptake values of the order of 10−4 and 10−5, respectively. On kaolinite, the uptake coefficient decreased with increasing O3 residence time τg thus indicating a complex mechanism. In contrast, γ decreased and became independent of τg at long residence time after long exposure to O3. For all uptake experiments the disappearance of O3 was accompanied by the formation of O2. The different mineral dust surrogates may be more accurately distinguished by their time‐dependent O2 yield r(t) rather than the magnitude of γ. The heterogeneous reaction of O3 on mineral dust has been found to be noncatalytic and of limited importance in the atmosphere. © 2006 Wiley Periodicals, Inc. Int J Chem Kinet 38: 407–419, 2006
Clay‐PMMA Nanocomposites by Photoinitiated Radical Polymerization Using Intercalated Phenacyl Pyridinium Salt Initiators
Authors: Nese Alper , Sen Sinan , Tasdelen Mehmet Atilla , Nugay Nihan , Yagci Yusuf
Published: April 2006

Summary: In situ synthesis of poly(methyl methacrylate) (PMMA) nanocomposites by photopolymerization using organophilic montmorillonite (MMT) as the layered clay is reported. MMT clay was ion exchanged with N‐phenacyl, N,N‐dimethylanilinium hexafluoro phosphate (PDA) which acts as both suitable intercalant‐ and photo‐initiator. These modified clays were then dispersed in methyl methacrylate (MMA) monomer in different loading degrees to carry out the in situ photopolymerization. Intercalation ability of the photoinitiator and exfoliated nanocomposite structure were evidenced by both X‐ray diffraction (XRD) spectroscopy and transmission electron microscopy (TEM). Thermal properties and morphologies of the resultant nanocomposites were also studied.

Schematic representation of clay‐PMMA nanocomposites by photoinitiated radical polymerization.

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Schematic representation of clay‐PMMA nanocomposites by photoinitiated radical polymerization.
A Novel Strategy to Synthesize Double Comb‐Shaped Water Soluble Copolymer by RAFT Polymerization
Authors: Han De‐Hui , Pan Cai‐Yuan
Published: April 2006

Summary: A double comb‐shaped water soluble copolymer, poly[poly(ethylene oxide) methyl ether methacrylate]‐block‐poly(N‐isopropylacrylamide)‐block‐poly[poly (ethylene oxide) methyl ether methacrylate], abbreviated as [P(MA‐MPEO)‐block‐PNIPAM‐block‐P(MA‐MPEO)], with a controlled molecular weight and narrow polydispersity was successively synthesized using a macromonomer technique. The 60Co γ irradiation polymerization of MA‐MPEO in the presence of dibenzyl trithiocarbonate (DBTTC) at room temperature afforded a polymer, P(MA‐MPEO)‐SC(S)S‐P(MA‐MPEO), which was subsequently used as a macro RAFT agent in the RAFT polymerization of N‐isopropylacrylamide, and water soluble double comb‐shaped copolymers, P(MA‐MPEO)‐block‐PNIPAM‐block‐P(MA‐MPEO), were successfully obtained.

Structure of the double comb‐shaped copolymer.

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Structure of the double comb‐shaped copolymer.
The Role of Oxidation in the Migration Mechanism of Layered Silicate in Poly(propylene) Nanocomposites
Authors: Zammarano Mauro , Gilman Jeffrey W. , Nyden Marc , Pearce Eli M. , Lewin Menachem
Published: April 2006

Summary: Evidence of clay migration from the core to the surface of poly(propylene)/montmorillonite nanocomposites is provided. A three‐ to fivefold increase in the clay concentration of the surface is obtained during isothermal heating in oxidative atmosphere. The mechanism of migration is investigated by means of attenuated total reflectance Fourier transform infrared spectrometry. It is shown that oxygen plays a fundamental role in the migration mechanism.

ρSi versus c for the annealed samples.

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ρSi versus c for the annealed samples.
The Local and Collective Mobility in Polymer Chains and Networks with Included Rigid Particles Elastically Connected with the Network
Authors: Gotlib Yuli Ya. , Torchinskii Isaak A. , Toshchevikov Vladimir P. , Shevelev Vladimir A.
Published: April 2006

Summary: The theory of molecular mobility of a polymer network with included rod‐like particles is developed. The case is considered when the length of rods is comparable or greater than the average distance between neighboring cross‐links of the primary network. The long‐scale dynamics of the network is described by means of a regular cubic “coarse‐grained” model. The junctions of this model describe the great network fragments (domains) the sizes of which are near to the average distance between neighboring rods.The quasi‐elastic interactions between rods and network fragments lead to a broad relaxation spectrum for included rods as compared with free rods which are characterized by a single relaxation time of rotational diffusion. The frequency dependence of the dielectric loss factor of included rods is calculated for rods with permanent dipole moments directed parallel to the long axes of the rods chaotically distributed in the network. The frequency dependence of dynamic modulus of a polymer network with included rods is obtained. The increment in the dynamic modulus of the relatively short network motions (smaller than the distance between rods) also is taken into account. The broad relaxation spectrum of included rods leads to appearance of several maximums on the frequency dependences of both the dielectric loss factor and dynamical modulus.
Synthesis and Characterization of Deuterated Glycidyl Azide Polymer (GAP)
Authors: Ringuette Sophie , Dubois Charles , Stowe Robert A. , Charlet Gérard
Published: April 2006

Decomposition mechanisms of propellants are of great interest in understanding performance issues of chemical propulsion systems. The characterization of physico‐chemical properties of glycidyl azide polymer (GAP), specifically deuterated analogs, was investigated in this study. The purpose of this new approach is to identify the key steps in thermal decomposition mechanism of GAP. The present work shows that the use of deuterated GAP is a good method to study the decomposition pathway of energetic polymers. The polymerization process was successful, but was nevertheless affected by the use of the isotopic monomer since the resulting polymers had a slightly lower molecular weight. The chemical characterization of the deuterated GAPs by NMR and FTIR confirm the structure of these new polymers. The TGA analyses show a larger weight loss during the first step of decomposition for labeled GAP suggesting that molecular nitrogen and heavier compounds are produced simultaneously.
Growth by LPCVD, crystallization and characterization of SiGe nanoparticles for nanoelectronic devices
Authors: Ortiz M. I. , Sangrador J. , Rodríguez A. , Rodríguez T. , Kling A. , Franco N. , Barradas N. P. , Ballesteros C.
Published: April 2006

Amorphous SiGe nanoparticles embedded in an oxide matrix, with controlled composition, diameter of a few nm, located in the same plane and with an areal density above 1012 cm–2 have been deposited by Low Pressure Chemical Vapour Deposition in a single run using a conventional hot wall reactor. The deposited nanoparticles were crystallized by Rapid Thermal Annealing. X‐ray Reflectometry and Rutherford Backscattering Spectrometry, with models developed for these purposes, have been tested as fast and reliable analytical tools to determine the composition, size and areal density of the nanoparticles. Transmission Electron Microscopy has been used to validate the results and to study the nanoparticle crystallization. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of magnetic field on spin blockade lifting of weakly coupled quantum dots
Authors: Iñarrea Jesús , Platero Gloria , MacDonald Allan H.
Published: April 2006

We study the electronic transport through a double quantum dot subjected to spin blockade. Experiments of current rectification by Pauli exclusion principle in double quantum dots are reproduced with our model based in the density matrix formalism. Our calculations include a self‐consistent description of the electron and nuclei spin dynamics within the double dot which indicates that the current leakage experimentally observed in the spin‐blockade region of the current–voltage curve, occurs due to spin‐flip processes induced by hyperfine interaction between the electrons and nuclei spins. We show as well how a magnetic field applied to the sample, in the direction of the current, allows excited states to participate in the electronic current and removes spin blockade. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
First principles calculation of isolated intermediate bands formation in a transition metal‐doped chalcopyrite‐type semiconductor
Authors: Palacios P. , Sánchez K. , Conesa J. C. , Wahnón P.
Published: April 2006

Density Functional Theory (DFT) calculations at the GGA level have been carried out for Ti‐substituted chalcopyrite‐type CuGaS2, as it might constitute an intermediate band material of the kind that has been proposed to lead to enhanced efficiency photovoltaic cells. According to these calculations an intermediate band appears when Ti substitutes Ga at a 25% level in this structure, resulting in a magnetic half‐metallic compound. This intermediate band slightly overlaps the conduction band and, when a higher accuracy calculation approach like the introduction of a Hubbard‐type empirical correction is used (GGA + U method), it splits leaving a filled narrow band, well isolated inside the band gap. Considering the nanocrystalline form in which these chalcopyrite‐type compounds are used in solar cells, an assessment of the effects of a small crystal size in this system have been carried out with a slab model. In this calculation a decreased bandgap width is observed, which can be as a result of surface termination effects. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Role of oil extract of garlic (Allium sativum Linn.) on intestinal transference of calcium and its possible correlation with preservation of skeletal health in an ovariectomized rat model of osteoporosis
Authors: Mukherjee Maitrayee , Das Asankur Sekhar , Das Dolan , Mukherjee Sandip , Mitra Smita , Mitra Chandan
Published: April 2006

The present study was undertaken to examine the effects of an oil extract of garlic on the in vivo intestinal transference of calcium, and also to verify its role in maintaining the bone mineral content and bone tensile strength in an ovariectomized rat model of osteoporosis. The results suggest that, in this experimental model, oil extract of garlic promotes intestinal transference of calcium by modulating the activities of both intestinal alkaline phosphatase and Ca2+ activated ATPase. Also the observed low bone mineral content and low bone tensile strength in these rats were significantly restored by garlic oil supplementation. Further, garlic oil supplementation was able to revive partially the bilateral ovariectomy‐induced decrease in the serum estrogen titer. The serum parathyroid hormone level, however, was found unaltered in these rats. The garlic oil supplemented partial recovery in serum estrogen titer in bilaterally ovariectomized rat was found to be persistently associated with enhanced calcium transference and better preservation of bone mineral content. The results of this study propose that the phytoestrogenic efficacy of an oil extract of garlic prevents ovarian hormone deficiency induced bone mineral loss possibly by promoting intestinal transference of calcium through the partial revival of the serum estrogen titer. Copyright © 2006 John Wiley & Sons, Ltd.
Effect on capillary permeability in rabbits of iridoids from Buddleia scordioides
Authors: Gutierrez Rosa Martha Perez , Solis Rosario Vargas , Baez Efren Garcia , Martinez Francisco Martinez
Published: April 2006

The methanol soluble fraction of the leaves of Buddleia scordioides after column chromatography resulted in the isolation of two known iridoid glucosides, catalpol and methylcatalpol. The structures were elucidated by extensive 1D‐2D‐NMR spectroscopy. The structure of methylcatalpol was confirmed by single‐crystal x‐ray diffraction. These compounds showed protective activity against increased (both chloroform and histamine) skin vascular permeability in rabbits. The protective effect was measured as the reduction in leakage of Evans blue. The results showed that the iridoids produced a significant inhibition of microvascular permeability. A comparison was made between the action of the iridoids and a known inhibitor of vascular permeability, troxerutin (50 mg/kg). Methylcatalpol and catalpol were found to be less effective than troxerutin. Copyright © 2006 John Wiley & Sons, Ltd.
The pharmacological effects of Salvia species on the central nervous system
Authors: Imanshahidi Mohsen , Hosseinzadeh Hossein
Published: April 2006

Salvia is an important genus consisting of about 900 species in the family Lamiaceae. Some species of Salvia have been cultivated world wide for use in folk medicine and for culinary purposes. The dried root of Salvia miltiorrhiza, for example, has been used extensively for the treatment of coronary and cerebrovascular disease, sleep disorders, hepatitis, hepatocirrhosis, chronic renal failure, dysmenorrhea, amenorrhea, carbuncles and ulcers. S. officinalis, S. leriifolia, S. haematodes, S. triloba and S. divinorum are other species with important pharmacological effects. In this review, the pharmacological effects of Salvia species on the central nervous system will be reviewed. These include sedative and hypnotic, hallucinogenic, skeletal muscle relaxant, analgesic, memory enhancing, anticonvulsant, neuroprotective and antiparkinsonian activity, as well as the inhibition of ethanol and morphine withdrawal syndrome. Copyright © 2006 John Wiley & Sons, Ltd.
A New Highly Convergent Entry to Densely Functionalized Aziridines Based on the Ugi Reaction
Authors: Banfi Luca , Basso Andrea , Guanti Giuseppe , Paravidino Monica , Riva Renata
Published: April 2006

The products of an Ugi‐4CR employing lactate‐derived O‐protected α‐hydroxycarbonyl derivatives underwent, during the subsequent O‐deprotection reaction, an unexpected acyl migration from nitrogen to oxygen. After ester saponification, treatment of the resulting α‐aminoalcohol with mesyl chloride gave rise to a regioselective and stereospecific cyclization to give a series of highly functionalized aziridines in good overall yield.
Production of Small Libraries Optimising and Examining the Scope of Aqueous Acceleration of the Passerini Reaction
Authors: Extance Andrew R. , Benzies David W. M. , Morrish James J.
Published: April 2006

It has been reported that the rate of the Passerini reaction is accelerated in water or in a mixture of water and an organic solvent. Here, the synthesis of small libraries using the Passerini reaction in a biphasic system is described. Examination of the effects of stoichiometry and different reagents demonstrated the ability to produce material of high purity without chromatography, within a specified structural scope.
Water molecules as structural determinants among prions of low sequence identity
Authors: De Simone Alfonso , Dodson Guy G. , Fraternali Franca , Zagari Adriana
Published: April 2006

The nature of the factors leading to the conversion of the cellular prion protein (PrPC) into its amyloidogenic isoform (PrPSc) is still matter of debate in the field of structural biology. The NMR structures of non‐mammalian PrPC (non‐mPrP) from frog, chicken and turtle [Calzolai, L., Lysek, D.A., Perez, D.R., Guntert, P. and Wuthrich, K. (2005) Prion protein NMR structures of chickens, turtles, and frogs. Proc. Natl. Acad. Sci. USA 102, 651–655] have provided some new and valuable information on the scaffolding elements that preserve the PrPC folding, despite their low sequence identity with the mammalian prions (mPrP). The present molecular dynamics study of non‐mPrPC focuses on the hydration properties of these proteins in comparison with the mammalian ones. The data reveal new insights in the PrP hydration and focus on the implications for PrPC folding stability and its propensity for interactions. In addition, for the first time, a role in disfavoring the PrPC aggregation is suggested for a conserved β‐bulge which is stabilized by the local hydration.
New PKCδ family members, PKCδIV, δV, δVI, and δVII are specifically expressed in mouse testis
Authors: Kawaguchi Takafumi , Niino Yuko , Ohtaki Hirokazu , Kikuyama Sakae , Shioda Seiji
Published: April 2006

We isolated and characterized four new PKCδ isoforms, PKCδIV, δV, δVI, and δVII, specifically expressed in the mouse testis. These isoforms possess neither V1 nor C2‐like domains. Moreover, PKCδVI and δVII have a different last exon as their V5 domain. The transcription of PKCδIV, δV, δVI, and δVII is initiated from the same site in the upstream region of exon4 of the PKCδ gene. They are expressed exclusively in the testis in an age‐dependent manner. PKCδIV and δV are expressed in spermatids with sperm maturation stage‐specific manner, and that PKCδVI and δVII are expressed in spermatogonia and spermatocytes.
Clinical evaluation of multimodal environmental modification (MEMO) in the management of cats with idiopathic cystitis
Authors: Buffington C. A. Tony , Westropp Jodi L. , Chew Dennis J. , Bolus Roger R.
Published: April 2006

This prospective observational study evaluated client-reported recurrence of lower urinary tract signs (LUTS) and other signs of abnormalities in cats with idiopathic cystitis after institution of multimodal environmental modification (MEMO). Forty-six client-owned indoor-housed cats with idiopathic cystitis, diagnosed based on a history of recurrent LUTS and evidence of absence of urolithiasis or bacterial urinary tract infection were studied. In addition to their usual care, clients were offered recommendations for MEMO based on a detailed environmental history. Cases were followed for 10 months by client contact to determine the effect of MEMO on LUTS and other signs. Significant ( P<0.05) reductions in LUTS, fearfulness, nervousness, signs referable to the respiratory tract, and a trend ( P<0.1) toward reduced aggressive behavior and signs referable to the lower intestinal tract were identified. These results suggest that MEMO is a promising adjunctive therapy for indoor-housed cats with LUTS, and should be followed up with prospective controlled clinical trials.
IMPROVING TAX ADMINISTRATION: A CASE STUDY OF THE UGANDA REVENUE AUTHORITY
Authors: Kangave Jalia
Published: April 2006

KANGAVE, JALIA, Improving tax administration: a case study of the Uganda Revenue authority, Journal of African Law, 49, 2 (2005): 145–176

The prevalence of poverty in developing countries demands that these countries should improvise internal revenue generating projects to supplement, or better still, ultimately significantly reduce dependence on foreign funding. This way self-sustaining economies will be built. One such internal revenue-generating mechanism, and perhaps the most commonly used, is taxation. This paper makes a case for tax administration as a tool of increasing the contribution of tax revenue to Gross Domestic Product, and consequently, a means of reducing the gap between the rich and the poor. The goal of this paper is to propose ways in which the Uganda Revenue Authority (the URA) can improve its tax administration. To achieve this objective, the paper begins with a detailed discussion of the URA's structure and the procedures it follows in collecting taxes. It then highlights the problems that may arise from such structure and procedures, before making proposals on how the URA can reform its organizational structure and processes to maximize its potential in revenue collection capabilities.
A FULL LOAF IS BETTER THAN HALF: THE CONSTITUTIONAL PROTECTION OF ECONOMIC, SOCIAL AND CULTURAL RIGHTS IN MALAWI
Authors: Chirwa Danwood Mzikenge
Published: April 2006

CHIRWA, DANWOOD MZIKENGE, A full loaf is better than half: the constitutional protection of economic, social and cultural rights in Malawi, Journal of African Law, 49, 2 (2005): 207–241

The last two decades have seen a new wave of constitution-making in Africa as many countries changed from autocracy to democracy. Malawi followed the trend by adopting a new Constitution in 1994 to mark the end of a 30-year, dictatorial one-party regime. This Constitution breaks with traditional constitutions by recognizing economic, social and cultural rights. However, few of these rights are entrenched in the Bill of Rights as justiciable rights. The rest are enshrined as unenforceable principles of national policy. These provisions and the jurisprudence they have generated thus far are discussed critically. It is argued that while the Malawian Constitution deserves acclaim for recognizing these rights, the model adopted for protecting them fails to give full effect to the notion of the indivisibility of all rights and is not good enough for a poor country, which is also in transition to democracy. Not only was Malawi's choice of this model not preceded by a careful and reasoned examination of the existing models and the local circumstances, it was also made without wide public consultations. The ways, based on the existing constitutional provisions, in which the protection of these rights can be improved are explored.
Tornwaldt's cyst formation after concurrent chemoradiotherapy for nasopharyngeal carcinoma
Authors: Chang S-L , Wu T-C , Yiu C-Y
Published: April 2006

The complications of concurrent chemoradiotherapy for nasopharyngeal carcinoma include dryness of mouth, sensorineural hearing loss, dental caries, trismus, pituitary dysfunction, myelitis, paralysis of cranial nerves IX–XII, massive neck fibrosis and pharyngeal wall necrosis. Tornwaldt's cyst formation after concurrent chemoradiotherapy for nasopharyngeal carcinoma has not been reported previously in the world literature. Tornwaldt's cyst, a persistent pharyngeal bursa, is found in about 3 per cent of the adult population, although the majority of these are asymptomatic. We describe the previously unreported complication of Tornwaldt's cyst formation after concurrent chemoradiotherapy for nasopharyngeal carcinoma.