bluuebunny/crossref_metadata_2025 huggingface dataset:
AAV‐mediated knockdown of phospholamban leads to improved contractility and calcium handling in cardiomyocytes
Authors: Andino Lourdes M. , Takeda Morihiko , Kasahara Hideko , Jakymiw Andrew , Byrne Barry J. , Lewin Alfred S.
Published: December 2007

Background

Reduced contractility due to dysregulation of intracellular calcium (Ca2+) is a common pathologic feature of chronic heart failure. Calcium stores in the sarcoplasmic reticulum play a major role in regulating cardiac contractility. Several animal models of heart failure have been treated by altering the regulation of the sarcoplamic reticulum ATPase through ablation or down‐regulation of its inhibitor peptide, phospholamban (PLN).

Methods

We have designed two small hairpin RNAs (shRNAs) to block the synthesis of PLN via RNA interference. These were tested in cell culture using a co‐transfection assay and using adeno‐associated virus (AAV)‐mediated delivery to cardiomyocytes. Reverse‐transcription polymerase chain reaction (RT‐PCR) and Western blots were used to measure reduction in PLN mRNA and protein levels. Reduction of PLN was also documented by indirect immunofluorescence. Free cytosolic calcium and contractile properties of transduced cardiomyocytes was examined on fura‐2‐loaded cells. Direct cardiac injection was used to deliver AAV1‐shRNAs to mice, and reduction of PLN was measured by indirect immunofluorescence.

Results

Both siRNAs led to significant reduction of PLN RNA and protein levels in cultured cells. Down‐regulation of PLN led to enhanced cell shortening and relaxation and to a decrease in the time constant of calcium decay, signs of improved contractility and calcium handling. In the hearts of AAV‐infected mice, shRNA‐transduced cells showed significant reduction in the level of PLN.

Conclusions

Our results suggest that AAV‐delivered shRNAs mediated physiologically significant suppression of phospholamban that may be useful in combating the effects of chronic heart failure. Copyright © 2007 John Wiley & Sons, Ltd.
Macromol. Biosci. 12/2007
Authors: Prime Emma L. , Cooper‐White Justin J. , Qiao Greg G.
Published: December 2007

Cover: A novel poly(lactic acid)‐based polymer containing pendent amine‐specific reactive groups was synthesized and cast into thin films, allowing for the covalent attachment of the cell adhesion peptide GRGDS to the surface. Subsequent cell adhesion studies with 3T3 fibroblasts showed increased cellular adhesion and spreading over unmodified films. Further details can be found in the article by E. L. Prime, J. J. Cooper‐White, and G. G. Qiao* on page 1272.
The role of executive function and attention in gait
Authors: Yogev‐Seligmann Galit , Hausdorff Jeffrey M. , Giladi Nir
Published: December 2007

Until recently, gait was generally viewed as a largely automated motor task, requiring minimal higher‐level cognitive input. Increasing evidence, however, links alterations in executive function and attention to gait disturbances. This review discusses the role of executive function and attention in healthy walking and gait disorders while summarizing the relevant, recent literature. We describe the variety of gait disorders that may be associated with different aspects of executive function, and discuss the changes occurring in executive function as a result of aging and disease as well the potential impact of these changes on gait. The attentional demands of gait are often tested using dual tasking methodologies. Relevant studies in healthy adults and patients are presented, as are the possible mechanisms responsible for the deterioration of gait during dual tasking. Lastly, we suggest how assessments of executive function and attention could be applied in the clinical setting as part of the process of identifying and understanding gait disorders and fall risk. © 2007 Movement Disorder Society
Brain parenchyma sonography and 123I‐FP‐CIT SPECT in Parkinson's disease and essential tremor
Authors: Doepp Florian , Plotkin Michail , Siegel Lara , Kivi Anatol , Gruber Doreen , Lobsien Elmar , Kupsch Andreas , Schreiber Stephan J.
Published: December 2007

We aimed to investigate the accuracy of transcranial brain parenchyma sonography (TCS) for differentiation between idiopathic Parkinson's disease (PD) and essential tremor (ET) in comparison to 123I‐FP‐CIT SPECT (FP‐CIT SPECT). Seventy‐four patients, in whom PD or ET was suspected on the basis of clinical criteria, were analyzed. The echogenicity of the substantia nigra (SN) and the striatal binding of dopamine transporters (DAT) were evaluated by TCS and FP‐CIT SPECT, respectively. Three patients were excluded due to an insufficient transtemporal bone window using TCS. Forty‐six and 25 patients were clinically classified as PD and ET. SPECT revealed a reduced DAT binding in 42 of all 71 included patients. Thirty‐six of the 42 patients with abnormal FP‐CIT SPECT findings had a pathological SN hyperechogenicity, whereas TCS findings in the remaining 6 patients were normal. In 27 of 29 patients with normal SPECT findings the SN echogenicity was regular. Referring to FP‐CIT SPECT, the sensitivity and specificity of TCS for detection of PD were 86 and 93%; the positive and negative predictive values were 95 and 82%, respectively. Sensitivity and specificity in detection of clinically diagnosed PD patients were 78 and 92% for TCS and 91 and 100% for FP‐CIT SPECT, respectively. In patients with pathological FP‐CIT SPECT and pathological TCS, the extent of SN hyperechogenicity did not correlate with the degree of reduction in dopamine transporter binding on the side opposite of the more affected limb. TCS allows a reliable differentiation of PD and ET. The TCS SN hyperechogenicity does not correlate with the extent of dopaminergic neuron degeneration. © 2007 Movement Disorder Society
MR elastography of the lung with hyperpolarized 3He
Authors: McGee Kiaran P. , Hubmayr Rolf D. , Ehman R.L.
Published: December 2007

MR elastography (MRE) is a phase contrast–based technique for spatially mapping the mechanical properties of tissue‐like materials. While hyperpolarized noble gases such as helium‐3 (3He) have proven to be an ideal contrast mechanism for imaging of the lung using conventional MR techniques, their applicability for lung MRE is unknown, due to the fact that gases do not support shear. In this study, we report on the application of MRE to an ex vivo porcine lung specimen inflated with a hyperpolarized noble gas. Unlike proton MRE, shear wave propagation is encoded into the gas entrapped within the alveolar spaces rather than the parenchyma itself. These data provide first evidence of the technical feasibility of MRE of the lung using hyperpolarized noble gases. Magn Reson Med, 2007. © 2007 Wiley‐Liss, Inc.
A fast full multigrid solver for applications in image processing
Authors: Stürmer M. , Köstler H. , Rüde U.
Published: December 2007

We present a fast, cell‐centered multigrid solver and apply it to image denoising and non‐rigid diffusion‐based image registration. In both applications, real‐time performance is required in 3D and the multigrid method has to be compared with solvers based on fast Fourier transform (FFT). The optimization of the underlying variational approach results for image denoising directly in one time step of a parabolic linear heat equation, for image registration a non‐linear second‐order system of partial differential equations is obtained. This system is solved by a fixpoint iteration using a semi‐implicit time discretization, where each time step again results in an elliptic linear heat equation. The multigrid implementation comes close to real‐time performance for medium size medical images in 3D for both applications and is compared with a solver based on FFT using available libraries. Copyright © 2007 John Wiley & Sons, Ltd.
Preparation of colloidal stable fluoroalkyl end‐capped oligomer/silver nanocomposites––application to the surface modification of traditional organic polymers with these nanocomposites
Authors: Sawada Hideo , Sasaki Ayumu , Sasazawa Kazuo , Toriba Ken‐ichi , Kakehi Hiroshi , Miura Masashi , Isu Norifumi
Published: December 2007

A variety of fluoroalkyl end‐capped oligomers/silver nanocomposites were prepared by the reactions of silver ions with poly(methylhydrosiloxane) in the presence of fluoroalkyl end‐capped N,N‐dimethylacrylamide oligomer, N‐(1,1‐dimethyl‐3‐oxobutyl)acrylamide oligomer, N,N‐dimethylacrylamide cooligomer containing poly(dimethylsiloxane) segments in organic media such as toluene and 1,2‐ dichloroethane. These fluorinated oligomers/silver nanocomposites thus obtained were found to exhibit clear plasmon absorption bands around 420 nm related to the formation of silver nanoparticles. In particular, these composites could display narrow plasmon absorptions around 420 nm in toluene by the addition of trioctylamine (TOA). On the other hand, the corresponding non‐fluorinated N‐(1,1‐ dimethyl‐3‐oxobutyl)acrylamide oligomer was not able to afford such a plasmon absorption under similar conditions. These fluorinated oligomers/silver nanocomposites in organic media have been found to be stable for more than 10 days. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) measurements showed that silver nanoparticles could be effectively encapsulated into fluorinated oligomeric aggregate cores to afford colloidal stable fluorinated oligomers/silver nanocomposites. Fluorinated oligomers/silver nanocomposites were also applied to the surface modification of traditional organic polymers such as polystyrene (PSt) and poly(methyl methacrylate) (PMMA) to exhibit not only a good oleophobicity imparted by fluorine but also a higher surface antibacterial activity related to the silver nanoparticles on their surface. Copyright © 2007 John Wiley & Sons, Ltd.
Prenatal diagnosis of congenital lipoid adrenal hyperplasia (CLAH) by estriol amniotic fluid analysis and molecular genetic testing
Authors: Jean Amy , Mansukhani Mahesh , Oberfield Sharon E. , Fennoy Ilene , Nakamoto Jon , Atwan Maha , Lerer Israela , Neriah Ziva Ben , Zangen David H. , Chung Wendy K.
Published: December 2007

Objective

Congenital lipoid adrenal hyperplasia is an autosomal recessive condition due to mutations in Steroidogenic Acute Regulatory Protein (StAR) associated with the inability to synthesize all adrenal and gonadal steroids, resulting in adrenal insufficiency and failure to develop male genitalia in affected 46,XY individuals. We used two independent methods of prenatal diagnosis for CLAH.

Method

CLAH was diagnosed prenatally by measuring amniotic fluid estriol, adrenal, and gonadal hormone levels, and by mutation analysis for the c.201–202 delCT mutation in StAR.

Results

Prenatal testing diagnosed one affected and three unaffected fetuses in two families at risk for CLAH.

Conclusion

Prenatal testing for CLAH is effective, and targeted molecular genetic analysis should be considered in Palestinian families with a fetus with discordant 46,XY karyotype and female genitalia on ultrasound, and low maternal serum estriol. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and self‐assembly of amphiphilic dendronized conjugated polymers
Authors: Xiao Xing , Wu Yonggang , Sun Minghao , Zhou Jianjun , Bo Zhishan , Li Lin , Chan Chiming
Published: December 2007

Two kinds of amphiphilic dendronized conjugated polymers, polyfluorene (PF) and poly(binaphthyl‐alt‐fluorene) (PBF), were synthesized by Suzuki polycondensation of hydrophobic macromonomers with two nonpolar octyloxy chains and hydrophilic macromonomers with two polar oligo(ethylene oxide) chains. In these polymers, PF possesses a linear rod‐like backbone structure, and PBF adopts a folded rigid backbone structure. The different configurations in the conjugated main chains result in different supramolecular self‐assembly morphologies. The optical and thermal properties of PF and PBF were also studied. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 574–584, 2008
Water sorption by poly(tetrahydrofurfuril methacrylate)'s
Authors: Sanchis Maria J. , Díaz‐Calleja Ricardo , García‐Bernabé Abel , Alegría Luz , Gargallo Ligia , Radic Deodato
Published: December 2007

Polymers consisting of poly(heterocyclic methacrylate)s are considered as potential materials for clinical applications such as drug delivery and cartilage repair. Much of the success of these systems has been attributed to the complex nature of their water sorption properties. Dielectric permittivity is very sensitive to water sorption. Dielectric relaxation spectroscopy studies have been carried out on two heterocyclic poly(methacrylate)s: poly(tetrahydrofurfuryl methacrylate) (PTHFMA) and poly(3‐methyl tetrahydrofurfuryl methacrylate) (P3MTHFMA). The isochrones representing the dielectric losses show in both cases high conductivity at low frequencies and high temperatures. In PTHFMA two conductive processes are observed, which can be associated to the existence of two types of water sorption. These effects have been analyzed and were removed from the dielectric spectra by using classical empirical equations. Both polymers show ostensible α‐relaxation centered in the vicinity of 350 K at 100 Hz. This relaxation was analyzed by means of the empirical Havriliak‐Negami equation. Reminiscent β‐relaxation could also exist. Both polymers present well defined γ and δ subglass absorptions at approximately 120 K, 160 K for PTHFMA and 125 K, 163 K for P3MTHFMA, at 100 Hz, associated to local intramolecular relaxations in side groups. These relaxations were analyzed using semiempirical symmetric model. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 109–120, 2008
Kinetics of re‐embrittlement of (anti)plasticized glassy polymers after mechanical rejuvenation
Authors: Kierkels J. T. A. , Dona C.‐L. , Tervoort T. A. , Govaert L. E.
Published: December 2007

Mechanical rejuvenation is known to dramatically alter the deformation behavior of amorphous polymers. Polystyrene (PS)—for example, typically known as a brittle polymer—can be rendered ductile by this treatment, while a ductile polymer like polycarbonate (PC) shows no necking anymore and deforms homogeneously in tensile deformation. The effects are only of temporary nature, as because of physical aging the increasing yield stress, accompanied by intrinsic strain softening, renders PS brittle after a few hours, while for PC necking in tensile testing returns in a few months after the mechanical rejuvenation treatment. In this study, it is found that physical aging upon rejuvenation in both PS and PC can be delayed in two different ways: (1) by reducing the molecular mobility through antiplasticization and (2) by applying toughening agents (rubbery core–shell particles). For the first route, even though progressive aging is found to decrease with increasing amounts of antiplasticizer added, dilution of the entanglement network results in enhanced brittleness. Besides antiplasticization effects, also some typical plasticization effects are observed, like a reduction in matrixTg. For the second route, traditional rubber toughening using acrylate core–shell modifiers also results in a reduced yield stress recovery, and ductile tensile deformation behavior is observed even 42 months after mechanical rejuvenation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 134–147, 2008
Effects of glycyrrhizic acid on cocklebur‐induced hepatotoxicity in rat and human hepatocytes
Authors: Yin Jian , Li Donghui , Hu Weiming , Meng Qin
Published: December 2007

Herbal medicines are gradually being accepted for their low toxicity and high efficacy, but their hepatotoxicity still needs to be recognized. For the multiple compounds in herbs, hepatocytes in vitro would be a useful tool for the evaluation of herbal hepatotoxicity. This study aimed at cocklebur/atractyloside‐induced hepatotoxicity and the protective effects of glycyrrhizic acid (GA) against this toxicity using rat and human hepatocytes in monolayer culture. After a 48 h treatment, cocklebur as well as atractyloside induced concentration‐dependent hepatotoxicity according to obvious decreases of cell viability, intracellular glutathione (GSH) content and albumin secretion in rat hepatocytes. Compared with rat hepatocytes, human hepatocytes seemed to be less sensitive to cocklebur‐induced hepatotoxicity, indicative of species differences between humans and rats. Furthermore, as expected, GA showed significant protective effects on cocklebur hepatotoxicity in both human and rat hepatocytes. Overall, these results suggested that hepatocytes in vitro, particularly human hepatocytes, could be a useful tool for herbal hepatotoxicity screening in vitro. Copyright © 2007 John Wiley & Sons, Ltd.
Enhancing racial self‐understanding through structured learning and reflective experiences
Authors: Quaye Stephen John , Baxter Magolda Marcia B.
Published: December 2007

Intercultural maturity and the learning partnerships model are offered as frameworks for understanding the intersection of students' developmental levels and readiness for cross‐racial interactions, and for assisting educators in promoting racial self‐understanding. A case study is used to illustrate the usefulness of the model in supporting student engagement with race.
Arrayed MC‐CDMA reception in space‐time diffused multipath vector channels
Authors: Rashid Farrukh , Manikas Athanassios
Published: December 2007

Multi‐Carrier Code Division Multiple Access (MC‐CDMA) is a modulation scheme that combines the advantages of OFDM and CDMA to provide robustness against frequency selectivity in wireless channels. Arrayed MC‐CDMA systems combine MC‐CDMA and antenna array technology to harness the spatial and temporal ‘signatures’ of received signals, thus making it possible to realize high transmission rates envisioned for next generation wireless communications. Localized scattering, which occurs for each multipath, motivates the frequency selective wireless channel to be modelled as a diffused vector channel. In this paper, space‐time diffused vector channels for arrayed MC‐CDMA systems are modelled and analysed. Simulation studies show that the use of this diffused channel modelling in arrayed MC‐CDMA receivers yields better Bit Error Rate (BER) and SNIRoutperformance than receivers that ignore the presence of spatial and/or temporal diffusion. Copyright © 2007 John Wiley & Sons, Ltd.
Specification, proof, and model checking of the Mondex electronic purse using RAISE
Authors: George Chris , Haxthausen Anne E.
Published: December 2007

This paper describes how the communication protocol of Mondex electronic purses can be specified and verified against desired security properties. The specification is developed by stepwise refinement using the RAISE formal specification language, RSL, and the proofs are made by translation to PVS and SAL. The work is part of a year-long project contributing to the international grand challenge in verified software engineering.
Mechanising Mondex with Z/Eves
Authors: Freitas Leo , Woodcock Jim
Published: December 2007

We describe our experiences in mechanising the specification, refinement, and proof of the
Mondex Electronic Purse
using the Z/Eves theorem prover. We took a conservative approach and mechanised the original L
a
T
E
X sources without changing their technical content, except to correct errors. We found problems in the original specification and some missing invariants in the refinements. Based on these experiences, we present novel and detailed guidance on how to drive Z/Eves successfully. The work contributes to the Repository for the Verified Software Grand Challenge.
Hölder continuity of solutions of supercritical dissipative hydrodynamic transport equations
Authors: Constantin Peter , Wu Jiahong
Published: December 2007

We examine the regularity of weak solutions of quasi-geostrophic (QG) type equations with supercritical (

\alpha < 1/ 2

) dissipation

(−\mathrm{\Delta })^{\alpha }

. This study is motivated by a recent work of Caffarelli and Vasseur, in which they study the global regularity issue for the critical (

\alpha = 1/ 2

) QG equation [L. Caffarelli, A. Vasseur, Drift diffusion equations with fractional diffusion and the quasi-geostrophic equation, arXiv: math.AP/0608447, 2006]. Their approach successively increases the regularity levels of Leray–Hopf weak solutions: from

L^{2}

to

L^{\infty }

, from

L^{\infty }

to Hölder (

C^{\delta }

,

\delta > 0

), and from Hölder to classical solutions. In the supercritical case, Leray–Hopf weak solutions can still be shown to be

L^{\infty }

, but it does not appear that their approach can be easily extended to establish the Hölder continuity of

L^{\infty }

solutions. In order for their approach to work, we require the velocity to be in the Hölder space

C^{1−2\alpha }

. Higher regularity starting from

C^{\delta }

with

\delta > 1−2\alpha

can be established through Besov space techniques and will be presented elsewhere [P. Constantin, J. Wu, Regularity of Hölder continuous solutions of the supercritical quasi-geostrophic equation, Ann. Inst. H. Poincaré Anal. Non Linéaire, in press].
On the spectrum of a nonlinear planar problem
Authors: Gladiali Francesca , Grossi Massimo
Published: December 2007

We consider the eigenvalue problem

\begin{cases}
−\mathrm{\Delta }v = \lambda \mu e^{u_{\lambda }}v & \text{in }\Omega , \\
\|v\|_{\infty } = 1 \\
v = 0 & \text{on }\partial \Omega ,
\end{cases} \tag{0.1}

where

Ω

is a bounded smooth domain of

\mathbb{R}^{2}

,

\lambda > 0

is a real parameter and

u_{\lambda }

is a solution of

\begin{cases}
−\mathrm{\Delta }u_{\lambda } = \lambda e^{u_{\lambda }} & \text{in }\Omega , \\
u_{\lambda } = 0 & \text{on }\partial \Omega
\end{cases}

such that

\lambda \int _{\Omega }e^{u_{\lambda }}\rightarrow 8\pi

as

\lambda \rightarrow 0

. In this paper we study the asymptotic behavior of the eigenvalues

μ

of (0.1) as

\lambda \rightarrow 0

. Moreover some explicit estimates for the four first eigenvalues and eigenfunctions are given.

Other related results as the Morse index of the solution

u_{\lambda }

will be proved.
Dietary lipoic acid-dependent changes in the activity and mRNA levels of hepatic lipogenic enzymes in rats
Authors: Huong Doan Thi Thanh , Ide Takashi
Published: December 2007

Effects of dietary α-lipoic acid on hepatic and serum lipid concentrations and the activity and mRNA levels of lipogenic enzymes were examined in rats. Rats were fed experimental diets containing varying amounts of lipoic acid (0, 1, 2·5, 5 g/kg) for 21 d. Lipoic acid profoundly decreased serum and liver concentrations of TAG, and also lowered serum concentrations of phospholipid and NEFA, and the concentration of cholesterol in the liver. A hypoglycaemic effect of this compound was also observed. Lipoic acid dose-dependently decreased the activity and mRNA levels of fatty acid synthase, ATP-citrate lyase, glucose 6-phosphate dehydrogenase, malic enzyme and pyruvate kinase in the liver despite that reductions were considerably attenuated in the NADPH-producing enzymes. This compound also dose-dependently lowered the mRNA levels of spot 14, adiponutrin, stearoyl-CoA desaturase 1, and Δ5- and Δ6-desaturases. In addition, lipoic acid dose-dependently lowered serum concentrations of insulin and leptin, but increased those of adiponectin. Lipoic acid appeared to reduce hepatic lipogenesis and hence decreases serum and liver lipid levels. Alterations in serum concentrations of insulin and (or) adiponectin may trigger this consequence.
When to Coalesce: Early Versus Late Coalition Announcement in an Experimental Democracy
Authors: GOODIN ROBERT E. , GÜTH WERNER , SAUSGRUBER RUPERT
Published: December 2007

In multi-party democracies, several parties usually have to join together in coalition to form government. Many aspects of that process have been fairly fully investigated, others less so. Among the latter is the timing of the formation and announcement of coalitions.

While the dominant popular image may be one of parties meeting together after the election to hammer out a coalition agreement, pre-election coalitions of one sort or another are actually quite common. In almost half of the elections in OECD (Organization for Economic Co-operation and Development) countries since the Second World War, at least one pair of parties had pre-announced their intention to join together in government. A quarter of governments formed were based wholly (and another quarter in part) on pre-election agreements.

To date, such studies as there have been of pre-election coalitions have concentrated primarily on system-level explanations – features of the electoral system (majoritarian or proportional, and so on) that make such arrangements more or less likely.3 Here we shall instead look more at the agent-level logic of ‘early’ (pre-election) versus ‘late’ (post-election) coalition formation, from the point of view of voters and parties.

hypotheses concerning coalition timing

In the tradition of Downs and Riker and their coalition-theorist progeny, we shall assume that voters are interested primarily in getting policies adopted which are close to their ‘ideal points’ in policy space, and that parties are interested primarily in winning office to implement policies as close as possible to their ‘ideal points’ in policy space. That leads parties to strive for ‘minimal connected winning coalitions’: ‘connected’ in the sense that they link parties adjacent in policy space; ‘minimal’ in the sense that they involve the party's sharing power with the fewest parties backed by fewest voters that it can and still win.
Population structure ofCicada barbaraStål (Hemiptera, Cicadoidea) from the Iberian Peninsula and Morocco based on mitochondrial DNA analysis
Authors: Pinto-Juma G.A. , Quartau J.A. , Bruford M.W.
Published: December 2007

We assess the genetic history and population structure ofCicada barbarain Morocco and the Iberian Peninsula, based on analysis of the mitochondrial cytochromebgene. The divergence between Morocco and the Iberian Peninsula populations was strongly corroborated by the molecular data, suggesting genetically isolated populations with a low level of gene flow. The Ceuta population from Spanish North Africa was more similar to the Iberian populations than the surrounding Moroccan populations, suggesting that the Strait of Gibraltar has not been acting as a strict barrier to dispersal while the Rif Mountains have. The Iberian Peninsula specimens showed a signature of demographic expansion before that which occurred in Morocco, but some of the assumptions related to the demographic parameters should be considered with caution due to the small genetic variation found. The high haplotype diversity found in Morocco implies higher demographic stability than in the Iberian Peninsula populations. These results do not, however, suggest a Moroccan origin for Iberian cicadas; but the most northwest region in Africa, such as Ceuta, might have acted as a southern refuge for Iberian cicadas during the most severe climatic conditions, from where they could expand north when climate improved. The separation of two subspecies withinC. barbara(C. barbara lusitanicaandC. barbara barbara) finds support with these results.
Ambrose's Imperial Funeral Sermons
Authors: LUNN-ROCKLIFFE SOPHIE
Published: December 2007

Ambrose's funeral sermons on the emperors Valentinian and Theodosius have been analysed as texts borrowing from classical rhetorical traditions, and as repositories of detail about contemporary politics. However, the crucial context for these texts was ecclesiastical; they were sermons, preached in church in services during which lessons were read from the Bible. This article shows that a consideration of this particular historical and liturgical context helps to elucidate Ambrose's ‘levelling’ political thought, and that identifying the biblical cadences of the sermons, far from being obfuscatory, is the key to understanding them.
Quality of back vowels before /r/ in the American Inland North
Authors: Clark Michael J. , Hillenbrand James M.
Published: December 2007

Three American English diphthongs involving onsets in the back of the vowel space were investigated by means of acoustic measurements, discriminant analysis, and perceptual experiments. These diphthongs, termed DOOR/WAR, TOY, and STAR, were observed in the speech of ten young women residing in southern Michigan. The diphthongs were elicited in a variety of /b/-, /ɡ/-, and /h/-initial words (e.g. board, Boyd, and barred). Words with similar consonantal margins but different nuclei (e.g. bode, baud, and bod) were elicited, as well. The DOOR/WAR and TOY words were compared with bode and baud (and similar words with initial /ɡ/ and /h/), while the STAR words were compared with baud and bod (and similar words with initial /ɡ/ and /h/). All three methods of investigation showed that the initial part of the DOOR/WAR and TOY diphthongs more closely resembles that of bode than baud. On the other hand, the initial part of the STAR diphthong was shown to be intermediate between that of baud and that of bod.
On the Number of Tetrahedra with Minimum, Unit, and Distinct Volumes in Three-Space
Authors: DUMITRESCU ADRIAN , TÓTH CSABA D.
Published: December 2007

We formulate and give partial answers to several combinatorial problems on volumes of simplices determined bynpoints in 3-space, and in general inddimensions.

(i)

The number of tetrahedra of minimum (non-zero) volume spanned bynpoints in$\mathbb{R}$3is at most$\frac{2}{3}n^3-O(n^2)$, and there are point sets for which this number is$\frac{3}{16}n^3-O(n^2)$. We also present anO(n3) time algorithm for reporting all tetrahedra of minimum non-zero volume, and thereby extend an algorithm of Edelsbrunner, O'Rourke and Seidel. In general, for every$k,d\in \mathbb{N}, 1\leq k \leq d$, the maximum number ofk-dimensional simplices of minimum (non-zero) volume spanned bynpoints in$\mathbb{R}$dis Θ(nk).

(ii)

The number of unit volume tetrahedra determined bynpoints in$\mathbb{R}$3isO(n7/2), and there are point sets for which this number is Ω(n3log logn).

(iii)

For every$d\in \mathbb{N}$, the minimum number of distinct volumes of all full-dimensional simplices determined bynpoints in$\mathbb{R}$d, not all on a hyperplane, is Θ(n).
Pocket borough to county borough: power relations, elites and politics in nineteenth-century Grimsby
Authors: SHINNER P.J.
Published: December 2007

This article considers the relationship between landed culture and the emergent middle classes in a rapidly expanding urban context substantially removed from the more familiar examples. The port of Grimsby expanded rapidly in the second half of the nineteenth century, displaying many facets in common with other industrial centres and boasting a substantial middle-class presence from a relatively early stage. At the same time the extent to which Grimsby's middle classes assumed a leading role in the town's development is questionable and subject to qualification.
The magnetic field and its effects on the solar atmosphere in high resolution
Authors: Title Alan M.
Published: December 2007

The Sun's magnetic field is produced throughout the solar interior; it emerges and is dispersed by surface and subsurface flows, and then expands above the surface to dominate the structure of the corona. To resolve the effects of the magnetic field it is necessary to image the interior and measure its rotation and flow systems; track the responses of the magnetic fields to flows in the surface; and to follow the evolution of structures in the corona. Because the Sun is dynamic both high spatial and temporal resolution are essential. Because the Sun's magnetic field effects encompass the entire spherical exterior, the entire surface and outer atmosphere must be mapped. And because the magnetic field is cyclic high-resolution observations must be maintained over multiple cycles.
Joint Discussion 1 Particle acceleration – from solar system to AGN
Authors: Karlický Marian , Brown John C.
Published: December 2007

The scene is set for IAU JD01 on Cosmic Particle Acceleration: from Solar System to AGNs
Acceleration: problems and progress
Authors: Melrose Donald B.
Published: December 2007

Older ideas on acceleration are linked to current ideas to identify both the major successes in the field, and long-standing problems and difficulties that remain unresolved.
Evidence for solar shock production of heliospheric near-relativistic and relativistic electron events
Authors: Kahler Stephen W.
Published: December 2007

Properties of near-relativistic (E ≳ 30 keV, NR) and relativistic (E ≳ 0.3 MeV) electron events produced near the Sun and observed within 1 AU are reviewed. Observations suggest the CME-driven shocks are the sources of many events, but flares are often sources for NR events.
Radio and X-ray diagnostics of electrons accelerated in solar flares
Authors: Bárta Miroslav , Karlický Marian
Published: December 2007

Starting from 2.5D MHD modelling of solar flares on a global scale we calculate (using the PIC and test-particle simulations) the radio and X-ray emissions generated in solar flare reconnection. Our results – the radio and X-ray spectra and brightness distributions, and their dynamics – are directly comparable with observations providing thus a test of particle acceleration models as well as of the ‘standard’ global flare scenario.
Diffusive shock acceleration and radio emission from shell-type SNRs
Authors: Asvarov A. I.
Published: December 2007

Diffusive shock acceleration (DSA) in test-particle approximation is used for explaining the radio emission from shell-type SNRs.
Stochastic re-acceleration in the ICM
Authors: Brunetti Gianfranco , Lazarian Alex
Published: December 2007

Here we suggest that efficient stochastic particle re–acceleration in galaxy clusters may be driven by compressible modes. The damping of these modes is severely dominated by the TTD–resonance with thermal electrons and protons in the ICM. However, a small energy flux of these modes may be channelled into particle re-acceleration and this gives re-acceleration times of the order of ∼ 108 yrs, sufficient to mantain GeV radiating electrons in the ICM.
Kinetic approaches to non-linear particle acceleration at shock fronts
Authors: Gabici Stefano , Amato Elena , Blasi Pasquale , Vannoni Giulia
Published: December 2007

We review some recent progresses in semi–analytic kinetic approaches to the problem of non linear particle acceleration at non relativistic shock waves.
Joint Discussion 3 Solar active regions and 3D magnetic structure
Authors: Choudhary Debi Prasad , Sobotka Michal
Published: December 2007

Keeping in view of the modern powerful observing tools, among othersHinode(formerlySOLAR-B),STEREOand Frequency-Agile Solar Radiotelescope, and sophisticated modelling techniques, Joint Discussion 3 during the IAU General Assembly 2006 focused on the properties of magnetic field of solar active regions starting in deep interior of the Sun, from where they buoyantly rise to the coronal heights where the site of most explosive events are located. Intimately related with the active regions, the origin and evolution of the magnetic field of quiet Sun, the large scale chromospheric structures were also the focal point of the Joint Discussion. The theoretical modelling of the generation and dynamics of magnetic field in solar convective zone show that the interaction of the magnetic field with the Coriolis force and helical turbulent convection results in the tilts and twists in the emerging flux. In the photosphere, some of these fluxes appear in sunspots with field strengths up to about 6100 G. Spectro-polarimetric measurements reveal that the line of sight velocities and magnetic field of these locations are found to be uncombed and depend on depth in the atmosphere and exhibit gradients or discontinuities. The inclined magnetic fields beyond penumbra appear as moving magnetic features that do not rise above upper photospheric heights. As the flux rises, the solar chromosphere is the most immediate and intermediary layer where competitive magnetic forces begin to dominate their thermodynamic counterparts. The magnetic field at these heights is now measured using several diagnostic lines such as CaII854.2 nm, HI656.3 nm, and HeI1083.0 nm. The radio observations show that the coronal magnetic field of post flare loops are of the order of 30 G, which might represent the force-free magnetic state of active region in the corona. The temperatures at these coronal heights, derived from the line widths, are in the range from 2.4 to 3.7 million degree. The same line profile measurements indicate the existence of asymmetric flows in the corona. The theoretical extrapolation of photospheric field into coronal heights and their comparison with the observations show that there exists a complex topology with separatrices associated to coronal null points. The interaction of these structures often lead to flares and coronal mass ejections. The current MHD modelling of active region field shows that for coronal mass ejection both local active region magnetic field and global magnetic field due to the surrounding magnetic flux are important. Here, we present an extended summary of the papers presented in Joint Discussion 03 and open questions related to the solar magnetic field that are likely to be the prime issue with the modern observing facilities such asHinodeandSTEREOmissions.
Continuum-driven versus line-driven mass loss and the Eddington limit
Authors: Owocki Stanley P.
Published: December 2007

Basic stellar structure dictates that stars of ∼ 100 M⊙ or more will be close to the Eddington limit, with luminosities in excess of 106 L⊙, and radiation pressure contributing prominently to the support against gravity. Although it is formally possible to generate static structure models of even more massive stars, recent studies of dense clusters show there is a sharp cutoff at masses above ∼ 150 M⊙. This talk examines the role of extreme mass loss is limiting the masses of stars, emphasizing in particular that continuum driving, possibly associated with structural instabilities of radiation dominated envelope, can lead to much stronger mass loss than is possible by the usual line-scattering mechanism of steady stellar winds.

However, population studies of very young, dense stellar clusters now suggest quite strongly that there is a sharp cutoff at masses above ca. 150 M⊙ (see, e.g., the talk by Sally Oey, in this JD 05, p. 206). This is sometimes attributed to a mass limit on star formation by accretion processes, though there are competing formation scenarios by binary or cluster merging that would seem likely to lead to formation of even higher mass stars (see talks in JD14 and S237).

So given the above rough coincidence of the observational upper mass limit with the Eddington-limit domain of radiation-pressure dominance, it seems associated instabilities in stellar structure might actually be a more important factor in this upper mass limit, leading to extreme mass loss in LBV and/or giant eruption events, much as inferred from circumstellar nebulae observed around high mass stars like eta Carinae and the Pistol star.
The high-mass stellar IMF in different environments
Authors: Kroupa Pavel
Published: December 2007

The massive-star IMF is found to be invariable. However, integrated IMFs probably depend on galactic mass.
Evolution of ultra-massive stars
Authors: Yungelson Lev R.
Published: December 2007

We discuss the evolution of ultra-massive stars.
The end of the re-ionization epoch probed by Lyα emitters at z = 6.5
Authors: Kashikawa Nobunari
Published: December 2007

We report an extensive search for Lyα emitters (LAEs) at z = 6.5 in the Subaru Deep Field (SDF). We carried out spectroscopic observations with Subaru/Keck to identify LAEs at z = 6.5 that were selected by narrow-band excess at 920nm. We have identified eight new LAEs based on their significantly asymmetric Lyα emission profiles. This increases the sample of spectroscopically confirmed z = 6.5 LAEs in the SDF to 17. Based on this spectroscopic sample of 17, complemented by a photometric sample of 58 LAEs, we have derived a more accurate Lyα luminosity function (LF) of LAEs at z = 6.5, which reveals an apparent deficit at the bright end, of ∼0.75 mag fainter L*, compared with that observed at z = 5.7. The difference has 3σ significance, which is reduced to 2σ when cosmic variance is taken into account. Several LAEs with high Lyα luminosity have been actually identified by spectroscopy at z<5.7, while our LAE sample at z = 6.5 has no confirmed object having such a high Lyα luminosity. The LF of the rest UV continuum, which is not sensitive to neutral IGM, of our LAE sample has almost the same as those of LAEs at z = 5.7 and i-dropouts at z≃6, even at their bright ends. This result may imply that the reionization of the universe has not been completed at z = 6.5. The decline of the Lyα LF implies the cosmic neutral fraction xHI=0.45 based on a theoretical IGM model, although this predicted value is strongly model dependent. The spatial distribution of our LAE sample was found to be homogeneous over the field, based on three independent methods to quantify the clustering strength. The composite spectrum of our LAE sample clearly reveals an asymmetric Lyα profile with an extended red wing, which can be explained by either a galactic wind model composed of double Gaussian profiles, or by a reionization model expected from the damping wing profile. Although our result has uncertainties in LAE evolution and large cosmic variance, it can be interpreted that LAEs at z = 6.5 are at the end of the reionization epoch.
Metallicity and black hole masses of z≃6 quasars
Authors: Kurk Jaron D. , Walter Fabian , Riechers Dominik , Rix Hans-Walter , Wagner Stefan , Pentericci Laura , Fan Xiaohui
Published: December 2007

We present NIR spectroscopy of emission lines of a sample of five z≃6 quasars, including fainter objects than observed before. The measured FeII/MgII ratios are around solar and consistent with a lack of evolution of the metallicity of quasar BLRs up to z≃6, suggesting that stars in their hosts formed at z≫6. The BH masses, measured from both MgII and CIV line widths are within the range 2-16×108M⊙, the smallest found in such distant objects.
Constraints on Very Faint High-z Quasars
Authors: Dijkstra Mark
Published: December 2007

I discuss the constraints that can be derived on the abundance of high redshift (z>6) (mini)quasars from the unresolved soft X-Ray background. Furthermore, I will show how existing Lyα surveys can be used to probe the very faint MB≳-21 mag (i.e., ≳7–8 mag fainter than the SDSS quasars) end of the z≥,4.5 quasar luminosity function.
Dust at z>6. Observations and theory
Authors: Maiolino Roberto
Published: December 2007

I shortly review the investigation of dust in the early universe. I discuss the possible evolution of the dust properties, as well as the possible dust production mechanisms at z>6.
The first galaxies at cm and mm wavelengths
Authors: Walter Fabian , Carilli Chris L. , Bertoldi Frank , Cox Pierre , Menten Karl M.
Published: December 2007

Observations of the most distant (z≃6) QSOs in the centimetre and millimetre regime currently serve as the only direct probe of the host galaxies of these extreme systems in the Epoch of Re-ionization. Such observations reveal that about 1'3 of the hosts contain massive reservoirs of dust (>108M⊙) and molecular gas (>1010M⊙) – the fuel for galaxy formation, and also indicate coeval starbursts at a rate >103M⊙yr−1 adequate to form a large elliptical galaxy in a dynamical timescale. These data imply that a highly metal enriched, molecular ISM, can be generated in galaxies within 870 Myr of the Big Bang. High-resolution imaging of the gas also provide an estimate of the host galaxy dynamical mass. However, current observations are restricted to rare, hyper-luminous IR galaxies. I will close by considering the prospects of observing the gas, dust, and star formation in the first ‘normal’ galaxies (e.g., the Ly-α galaxies) into cosmic reionization (z>6), using ALMA and the EVLA.
Additional sources of ionization in the early universe and the 21cm line
Authors: Vasiliev Evgenii O. , Shchekinov Yuri A.
Published: December 2007

We consider the influence of decaying dark matter particles and ultra-high energy cosmic rays (UHECRs) on the ability of neutral gas at redshifts z = 10-50 to emit and absorb in the 21cm line. We show that the signal in 21 cm is sensitive to properties of decaying particles and UHECRs, and conclude that future radio telescopes (LOFAR, LWA and SKA) are able not only to detect 21cm signal originated from decaying particles and UHECRs, but discriminate between them as well.
Assessing the influence of metallicity on fragmentation of proto-galactic gas
Authors: Jappsen Anne-Katharina , Glover Simon C. O. , Klessen Ralf S. , Low Mordecai-Mark Mac
Published: December 2007

In cold dark matter cosmological models, the first stars to form are believed to do so within small protogalaxies. We study the influence of low levels of metal enrichment on the cooling and collapse of ionized gas in these protogalactic halos using three-dimensional, smoothed particle hydrodynamics simulations.
Large-scale patterns, complexes of solar activity and ‘active longitudes’
Authors: Ambrož Pavel
Published: December 2007

Typical latitude zones and longitude sectors with a dominant occurrence of newly emerging magnetic flux were systematically detected during three last activity cycles. Two long time persistent longitude sectors with the preferred occurrence of a new strong magnetic flux are characteristic for magnetic flux distribution and their rotation rate is latitude dependent in the relationship with differential rotation rate. Recent new information about the large-scale flows in convection zone relates to a concept of the expected giant cells and jets and show a new relationship with different scales of the large-scale circulation. Non-axially symmetric horizontal flow in upper part of convection zone gives a good motivation for an extension of the existing axially symmetric 2D models into new 3D concept.
Solar irradiance variability
Authors: Solanki Sami K.
Published: December 2007

We study solar irradiance variability. The current generation of models show that the irradiance since then has increased by between 0.9 and 1.5 W m−2.
Cyclic fluctuations in the differential rotation of active stars
Authors: Petit Pascal
Published: December 2007

Differential rotation is described in stellar dynamo models as one of the fundamental phenomena governing the amplification of magnetic fields in active stars.Using indirect imaging methods, the measurement of photospheric differential rotation is now achieved on a growing number of very active stars, a fraction of which exhibit temporal fluctuations of potentially large amplitude in their latitudinal shear, on a time-scale of a few years. I first describe the modeling tools on which such analysis is based, then discuss the implications of this observational work on our understanding of stellar dynamos and of the impact stellar magnetic fields may have on the dynamics of convective envelopes.
Topology of stellar coronae
Authors: Jardine Moira M.
Published: December 2007

While the existence of cycles in stellar chromospheric flux has been known for some time, the nature of the corresponding coronal response has been more elusive. We describe recent results on the relationship between cyclic variations in surface magnetic flux and coronal structure and re-assess the role of prominence observations in understanding the topology of stellar coronas. We present a new paradigm for prominence support which allows for extended prominences to co-exist with a compact corona. We discuss briefly the recent results on coronal structure in high- and low-mass stars and their implications for dynamo theory.
The impact of stellar activity on planets
Authors: Ribas Ignasi
Published: December 2007

The results of the Sun in Time program indicate that the X ray, far ultraviolet and ultraviolet fluxes of the young Sun were significantly higher than today. Similarly, the solar wind mayhave been much stronger in the past. Such environment of intense energy and particle emissions could have influenced the paleo-atmospheres of Solar System planets and, by extension, the habitability and stability of exoplanets.