bluuebunny/crossref_metadata_2025 huggingface dataset:
Indoor air quality investigation and health risk assessment at correctional institutions
Authors: Ofungwu Joseph
Published: April 2005

A comprehensive indoor air–quality (IAQ) investigation was conducted at a state correctional facility in New Jersey, USA with a lengthy history of IAQ problems. The IAQ investigation comprised preliminary indoor air screening using direct readout instrumentation, indoor air/surface wipe sampling and laboratory analysis, as well as a heating, ventilation, and air-conditioning system evaluation, and a building envelope survey. In addition to air sampling, a human health risk assessment was performed to evaluate the potential for exposure to site-related air contaminants with respect to the inmate and worker populations. The risk assessment results for the prison facility indicated the potential for significant health risks for the inmate population, possibly reflecting the effects of their confinement and extended exposure to indoor air contaminants, as compared to the prison guard and worker population. Based on the results of the risk assessment, several mitigation measures are recommended to minimize prison population health risks and improve indoor air quality at prison facilities.
An evaluation of United Kingdom environmental bovine spongiform encephalopathy risk assessment
Authors: Grist Eric P.M.
Published: April 2005

As a member of the group of diseases known as transmissible spongiform encephalopathies (TSEs), bovine spongiform encephalopathy (BSE) has been causally associated with a new variant of Creutzfeldt-Jakob disease (vCJD) in humans. Given the many uncertainties on the transmission and persistence of TSE pathogens in the environment, quantitative assessment of risks to humans and animals continues to remain a public health issue. This paper reviews quantitative BSE risk assessments undertaken in the United Kingdom since 1997 to address the potential for human exposure and theoretical health risks through environmental pathways. The review focuses on how model assumptions and methodology may influence the results.
A methodology for deriving tissue residue benchmarks for aquatic biota: A case study for fish exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin and equivalents
Authors: Steevens Jeffery A. , Reiss Mark R. , Pawlisz Andrew V.
Published: April 2005

Tissue residue-based toxicity benchmarks (TRBs) have typically been developed using the results of individual studies selected from the literature. In the past, TRBs have been developed using a point estimate (e.g., LC50 value) reported in a study on a single species deemed to be most closely related to the receptor of interest. Despite attempts to maximize the protectiveness and relevance of TRBs, their relationship to specific receptors remains uncertain, and their general applicability for use in broader ecological risk assessment contexts is limited. This article proposes a novel framework that establishes benchmarks as distributions rather than single-point estimates. Benchmark distributions allow the user to select a tissue concentration that is associated with the protection of a specific percentage of organisms, rather than linked to a specific receptor. A methodology is proposed for searching, reviewing, and analyzing linked, tissue residue effect data to derive benchmark distributions. The approach is demonstrated for contaminants having a dioxin-like mechanism of toxic action and is based on residue effects data for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and equivalents in early life stage fish. The calculated tissue residue benchmarks for 2,3,7,8-TCDD toxic equivalency (TEQ) derived from the resulting distribution could range from 0.057- to 0.699-ng TCDD/g lipid depending on the level of protection needed; the lower estimate is protective of 99% of fish species whereas the higher end is protective of 90% of fish species.
Application of multicriteria decision analysis in environmental decision making
Authors: Kiker Gregory A. , Bridges Todd S. , Varghese Arun , Seager Thomas P. , Linkov Igor
Published: April 2005

Decision making in environmental projects can be complex and seemingly intractable, principally because of the inherent trade-offs between sociopolitical, environmental, ecological, and economic factors. The selection of appropriate remedial and abatement strategies for contaminated sites, land use planning, and regulatory processes often involves multiple additional criteria such as the distribution of costs and benefits, environmental impacts for different populations, safety, ecological risk, or human values. Some of these criteria cannot be easily condensed into a monetary value, partly because environmental concerns often involve ethical and moral principles that may not be related to any economic use or value. Furthermore, even if it were possible to aggregate multiple criteria rankings into a common unit, this approach would not always be desirable because the ability to track conflicting stakeholder preferences may be lost in the process. Consequently, selecting from among many different alternatives often involves making trade-offs that fail to satisfy 1 or more stakeholder groups. Nevertheless, considerable research in the area of multicriteria decision analysis (MCDA) has made available practical methods for applying scientific decision theoretical approaches to complex multicriteria problems. This paper presents a review of the available literature and provides recommendations for applying MCDA techniques in environmental projects. A generalized framework for decision analysis is proposed to highlight the fundamental ingredients for more structured and tractable environmental decision making.
Polymer Blends
Authors: Horák Zdeněk , Fortelný Ivan , Kolařík Jan , Hlavatá Drahomíra , Sikora Antonín
Published: April 2005

Blending of two or more different polymers makes it possible to achieve various property combinations of the resulting material—mostly in a more cost‐effective way than by synthesis of new polymers. The resulting multicomponent and mostly heterogeneous blends are an extraordinarily important group of polymer materials, which comprise about a third of the world's polymer production. Common features of preparation, evaluation, and application of polymer blends are the main subject of the chapter.

The basic problems associated with the nonequilibrium phase structure and its coarsening, the effects of interfacial energy of components, the strategies of compatibilization of immiscible polymers, and methods of phase structure analysis are elucidated. Special attention is paid to mechanical properties of heterogeneous blends and their prediction. Commercially important types of polymer blends as well as recycling of commingled plastic waste are briefly discussed.
Thermal Analysis of Polymers
Authors: Chartoff Richard P. , Sircar Anil K.
Published: April 2005

Thermal analysisis defined by the International Confederation of Thermal Analysis and Calorimetry (ICTAC) as “a group of techniques in which a property of a sample is monitored against time or temperature while the temperature of the sample, in a specified atmosphere, is programmed.” The principal techniques employed are differential thermal analysis (DTA), differential scanning calorimetry (DSC), thermogravimetry (TGA), thermomechanical analysis (TMA), dynamic mechanical analysis (DMA), and dielectric analysis (DEA).

Chemical reactions and phase transitions as well as mechanical, acoustical, electrical, and optical properties, can be studied and evaluated by thermal analysis. Additional uses include quality control, determination of heat capacity, thermal expansion, thermal and oxidative stability, crystallization rates, phase separation, and numerous others. This article describes the techniques, data interpretation, and applications of the method.
Influence of CO2 on ultrasound‐induced polymerizations in high‐pressure fluids
Authors: Kuijpers M. W. A. , Jacobs L. J. M. , Kemmere M. F. , Keurentjes J. T. F.
Published: April 2005

A strong viscosity increase upon polymerization hinders cavitation and subsequent radical formation during an ultrasound‐induced bulk polymerization. Ultrasound‐induced radical polymerizations of methyl methacrylate (MMA) have been performed in CO2‐expanded MMA, as well as in bulk MMA. For this purpose, the phase behavior of CO2/MMA systems has been determined. With temperature oscillation calorimetry, the influence of CO2 on the viscosity and on the reaction kinetics of ultrasound‐induced polymerizations of MMA has been studied. In contrast to polymerizations in bulk, this technique shows that a low viscosity is maintained during polymerization reactions in CO2‐expanded MMA. As a consequence, a constant or even increasing polymerization rate is observed when pressurized CO2 is applied. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Multiple path‐based approach to image‐based street walkthrough
Authors: Lee Dong Hoon , Jung Soon Ki
Published: April 2005

Image‐based rendering for walkthrough in the virtual environment has many advantages should over the geometry‐based approach, due to the fast construction of the environment and photo‐realistic rendered results. In image‐based rendering technique, rays from a set of input images are collected and a novel view image is rendered by the resampling of the stored rays. Current such techniques, however, are limited to a closed capture space. In this paper, we propose a multiple path‐based capture configuration that can handle a large‐scale scene and a disparity‐based warping method for novel view generation. To acquire the disparity image, we segment the input image into vertical slit segments using a robust and inexpensive way of detecting vertical depth discontinuity. The depth slit segments, instead of depth pixels, reduce the processing time for novel view generation. We also discuss a dynamic cache strategy that supports real‐time walkthroughs in large and complex street environments. The efficiency of the proposed method is demonstrated with several experiments. Copyright © 2005 John Wiley & Sons, Ltd.
Polymeric Micelles and Nanoparticles from Block and Statistical Poly((RS)‐3,3‐dimethylmalic acid) Derivatives: Preparation and Characterization
Authors: Ouhib Farid , Randriamahefa Solo , Wintgens Véronique , Guérin Philippe , Barbaud Christel
Published: April 2005

Summary: Amphiphilic and biodegradable micelles and nanoparticles designed as potential drug carriers were prepared from biodegradable statistical and block copolyesters obtained by a living anionic ring‐opening process. These novel materials display amphiphilic properties arising from the joint presence of hydrophilic poly((RS)‐3,3‐dimethylmalic acid) and hydrophobic poly(hexyl (RS)‐3,3‐dimethylmalate) segments. Micelles obtained from a well‐defined block copolymer have been characterized by their critical aggregation concentration, and nanoparticles derived from statistical copolymer have been analyzed by transmission electron microscopy (TEM).

Electron transmission microphotography of nanoparticles of PDMMLAH30‐co‐He70 4.

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Electron transmission microphotography of nanoparticles of PDMMLAH30‐co‐He70 4.
Nanoscale Analysis of Polymer Interfaces by Energy‐Filtering Transmission Electron Microscopy
Authors: Horiuchi Shin , Yin Dehui , Ougizawa Toshiaki
Published: April 2005

Summary: Energy‐filtering transmission electron microscopy (EFTEM) was employed for the analysis of polymer‐polymer interfaces. To attain imaging and spectral analyses with a spatial resolution of 10 nm, problems arising in the EFTEM analysis for polymer specimens were investigated. Interfaces in poly(methyl methacrylate)/polystyrene‐co‐polyacrylonitrile random copolymer (PMMA/SAN) bilayer films annealed at different temperatures were analyzed by means of elemental mapping and Image‐EELS on EFTEM and the effect of the annealing temperature on the interfacial structures was also investigated.

magnified image
Diagnostic value of OCT3/4 for pre‐invasive and invasive testicular germ cell tumours
Authors: de Jong Jeroen , Stoop Hans , Dohle Gert R , Bangma Chris H , Kliffen Mike , van Esser Joost WJ , van den Bent Martin , Kros Johan M , Oosterhuis JW , Looijenga Leendert HJ
Published: April 2005

Human testicular germ cell tumours of adolescents and adults (TGCTs), the seminomatous and non‐seminomatous germ cell tumours, show morphological and biological similarities to normal embryonic development, presumably determined by their supposed cell of origin, the primordial germ cell/gonocyte. Based on this knowledge, OCT3/4, also known as POU5F1, was recently defined as a diagnostic marker for these tumour types. In the adult testis, positive immunohistochemistry for OCT3/4 is an absolute indicator for the presence of the TGCT precursor carcinoma in situ/intratubular germ cell neoplasia undifferentiated (CIS/ITGCNU), seminoma, and/or embryonal carcinoma. Several studies have confirmed this observation, using the same polyclonal antibody. The present study demonstrates the usefulness of OCT3/4 immunohistochemistry in a diagnostic setting of a consecutively collected series of more than 200 testicular tumours and over 80 testicular biopsies. Moreover, it is shown that a monoclonal antibody directed against OCT3/4 is as informative as the polyclonal antibody, both in immunohistochemistry and in western blot analysis. The antibodies are robust and applicable with different methods of pretreatment and storage of tissue. This allows routine application of this diagnostic marker. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Evidence that prostate gonadotropin‐releasing hormone receptors mediate an anti‐tumourigenic response to analogue therapy in hormone refractory prostate cancer
Authors: Gnanapragasam VJ , Darby S , Khan MM , Lock WG , Robson CN , Leung HY
Published: April 2005

Gonadotropin‐releasing hormone analogue (GnRHa) therapy is an established method of androgen withdrawal in the treatment of prostate cancer. The present study investigated if the expression of prostate GnRH receptors (GnRHRs) might influence the response to GnRHa. GnRHR protein expression was first studied in a panel of prostate cancer cell lines. In androgen‐dependent cells, GnRHR expression was unchanged following acute or chronic androgen withdrawal. In these cells, GnRHa significantly inhibited androgen‐induced cell proliferation (p = 0.01). In contrast, GnRHa was unable to further suppress basal levels of cell proliferation induced by androgen withdrawal. In androgen‐independent prostate cancer cells, variable levels of GnRHR expression were observed. In these cells, GnRHa treatment blocked cell proliferation (p = 0.001) and invasion (up to 70%) induced by fibroblast growth factor stimulation. Crucially, this effect was only evident in cells that expressed high levels of the GnRHR. GnRHa treatment also significantly inhibited the ability of these cells to recover from a cytotoxic insult (50% inhibition). The clinical significance of prostate GnRHR was tested by immunohistochemistry in a preliminary cohort of patients treated with GnRHa or surgical castration. There was no association between GnRHR expression and pathological grade, clinical stage, time to PSA nadir (p = 0.82) (n = 35) or progression to hormone refractory disease (p = 0.22) (n = 21), irrespective of the treatment method. GnRHa therapy in the presence of high GnRHR expression however, was found to be associated with longer disease‐specific survival (mean survival 85 months, p = 0.002). In contrast, high GnRHR expression was not associated with survival among surgically castrated patients (mean survival 50 months, p = 0.7). Taken together, these data support the notion of a functional interaction between GnRHa and the GnRHR, which results in an anti‐tumourigenic effect on prostate cancer cells. Findings from this report have direct implications for the use of GnRHR as a novel therapeutic target in hormone refractory prostate cancer. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Structure of poly(L‐lactic acid)s prepared by the dehydropolycondensation of L‐lactic acid with organotin catalysts
Authors: Shyamroy S. , Garnaik B. , Sivaram S.
Published: April 2005

The synthesis of low‐molecular‐weight (weight‐average molecular weight < 45,000 g/mol) lactic acid polymers through the dehydropolycondensation of L‐lactic acid was investigated. Polymerizations were carried out in solution with solvents (xylene, mesitylene, and decalin), without a solvent using different Lewis acid catalysts (tetraphenyl tin and tetra‐n‐butyldichlorodistannoxane), and at three different polymerization temperatures (143, 165, and 190 °C). The products were characterized with differential scanning calorimetry, size exclusion chromatography, vapor pressure osmometry, 13C NMR, and matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF). The resulting polymers contained less than 1 mol % lactide, as shown by NMR. The number‐average molecular weights were calculated from the ratio of the area peaks of ester carbonyl and carboxylic acid end groups via 13C NMR. The stereosequences were analyzed by 13C NMR spectroscopy on the basis of triad effects. Tetraphenyl tin was an effective transesterification catalyst, and the randomization of the stereosequence at 190 °C was observed. In contrast, the distannoxane catalyst caused comparatively less transesterification reaction, and the randomization of the stereosequences was slow even at 190 °C. The L‐lactic acid and D‐lactic acid isomers were added to the polymer chain in a small, blocky fashion. The MALDI‐TOF spectra of poly(L‐lactic acid) (PLA) chains doped with Na+ and K+ cations showed that the PLA chains had the expected end groups. The MALDI‐TOF analysis also enabled the simultaneous detection of the cyclic oligomers of PLA present in these samples, and this led to the full structural characterization of the molecular species in PLA. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2164–2177, 2005
RECOORD: A recalculated coordinate database of 500+ proteins from the PDB using restraints from the BioMagResBank
Authors: Nederveen Aart J. , Doreleijers Jurgen F. , Vranken Wim , Miller Zachary , Spronk Chris A.E.M. , Nabuurs Sander B. , Güntert Peter , Livny Miron , Markley John L. , Nilges Michael , Ulrich Eldon L. , Kaptein Robert , Bonvin Alexandre M.J.J.
Published: April 2005

State‐of‐the‐art methods based on CNS and CYANA were used to recalculate the nuclear magnetic resonance (NMR) solution structures of 500+ proteins for which coordinates and NMR restraints are available from the Protein Data Bank. Curated restraints were obtained from the BioMagResBank FRED database. Although the original NMR structures were determined by various methods, they all were recalculated by CNS and CYANA and refined subsequently by restrained molecular dynamics (CNS) in a hydrated environment. We present an extensive analysis of the results, in terms of various quality indicators generated by PROCHECK and WHAT_CHECK. On average, the quality indicators for packing and Ramachandran appearance moved one standard deviation closer to the mean of the reference database. The structural quality of the recalculated structures is discussed in relation to various parameters, including number of restraints per residue, NOE completeness and positional root mean square deviation (RMSD). Correlations between pairs of these quality indicators were generally low; for example, there is a weak correlation between the number of restraints per residue and the Ramachandran appearance according to WHAT_CHECK (r = 0.31). The set of recalculated coordinates constitutes a unified database of protein structures in which potential user‐ and software‐dependent biases have been kept as small as possible. The database can be used by the structural biology community for further development of calculation protocols, validation tools, structure‐based statistical approaches and modeling. The RECOORD database of recalculated structures is publicly available from http://www.ebi.ac.uk/msd/recoord. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Does structural and chemical divergence play a role in precluding undesirable protein interactions?
Authors: Jiménez José L.
Published: April 2005

To understand the evolutionary forces establishing, maintaining, breaking, or precluding protein–protein interactions, a comprehensive data set of protein complexes has been analyzed to examine the overlap between protein interfaces and the most conserved or divergent protein surface areas. The most divergent areas tend to be found predominantly away from protein interfaces, although when found at interfaces, they are associated with specific lack of cross‐reactivity between close homologues, like in antibody–antigen complexes. Moreover, the amino acid composition of highly variable regions is significantly different from any other protein surfaces. The variable regions present higher structural plasticity as a result of insertions and deletions, and favor charged over hydrophobic residues, a known strategy to minimize aggregation. This suggests that (1) a rapid rate of mutations at these regions might be continuously altering their properties, making difficult the coadaptation, in shape and chemical complementarity, to potential interacting partners; and (2) the existence of some form of selective pressure for variable areas away from interfaces to accumulate charged residues, perhaps as an evolutionary mechanism to increase solubility and minimize undesirable interactions within the crowded cellular environment. Finally, these results are placed into the context of the aberrant oligomerization of sickle‐cell anemia hemoglobin and prion proteins. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Electron ionization fragmentation mechanisms of different substituted 2,3‐dihydro‐ and 2,3,4,5‐tetrahydro‐1,5‐benzothiazepines
Authors: Ansari Farzana Latif , Hussain Latif , Nasir Saima , Sultana Sajida
Published: April 2005

The electron ionization induced fragmentations of ten biologically significant 2,3‐dihydro‐1,5‐benzothiazepines and the corresponding 2,3,4,5‐tetrahydro‐1,5‐benzothiazepines have been studied by low‐ and high‐resolution mass spectrometry. The fragmentations follow a general pattern, the details of which are discussed with respect to the nature and position of the substituent in the aromatic ring. The dihydro‐ and tetrahydro‐1,5‐benzothiazepines both undergo fragmentation through four routes (A–D). However, the most significant fragmentation takes place through route A, leading to the elimination of ring A or ring B of the molecule. The difference between the fragmentation patterns of dihydro‐ and tetrahydro‐1,5‐benzothiazepines appears mainly in route E where a phenylallylhydroxybenzene cation appears in all tetrahydro‐1,5‐benzothiazepines but is not observed in the corresponding dihydro derivatives. Copyright © 2005 John Wiley & Sons, Ltd.
Mappings of finite distortion: discreteness and openness for quasi-light mappings
Authors: Koskela Pekka , Hencl Stanislav
Published: April 2005

Let

f \in W^{1,n}(\Omega ,\mathbb{R}^{n})

be a continuous mapping so that the components of the preimage of each

y \in \mathbb{R}^{n}

are compact. We show that

f

is open and discrete if

|Df(x)|^{n}⩽K(x)J_{f}(x)

a.e. where

K(x)⩾1

and

K^{n−1}/ \Phi (\mathrm{\log }(e + K)) \in L^{1}(\Omega )

for a function

Φ

that satisfies

\int _{1}^{\infty }1/ \Phi (t)\:\mathrm{d}t = \infty

and some technical conditions. This divergence condition on

Φ

is shown to be sharp.

Soit

f \in W^{1,n}(\Omega ,\mathbb{R}^{n})

une application continue telle que les composantes connexes de la préimage de tat point

y \in \mathbb{R}^{n}

est compacte. On démontre que

f

est ouverte et discrète si

|Df(x)|^{n}⩽K(x)J_{f}(x)

p.p. oi

K(x)⩾1

et

K^{n−1}/ \Phi (\mathrm{\log }(e + K)) \in L^{1}(\Omega )

pour une fonction

Φ

telle que

\int _{1}^{\infty }1/ \Phi (t)\:\mathrm{d}t = \infty

et vérifiant des conditions techniques. La condition de divergence de l'intégrale est optimale.
On backward-time behavior of the solutions to the 2-D space periodic Navier–Stokes equations
Authors: Dascaliuc Radu
Published: April 2005

In 1995, Constantin, Foias, Kukavica, and Majda had shown that the 2-D space periodic Navier–Stokes equations have a rich set of the solutions that exist for all times

t \in \mathbb{R}

and grow exponentially in Sobolev

H^{1}

norm when

t\rightarrow −\infty

. In the present note we show that these solutions grow exponentially (when

t\rightarrow −\infty

) in any Sobolev

H^{m}

norm (

m⩾2

) provided the driving force is bounded in

H^{m−1}

norm.

En 1995 Constantin, Foias, Kukavica et Majda ont demontré que les équations de Navier–Stokes périodiques dans

\mathbb{R}^{2}

possèdent un ensemble ample des solutions qui existent pour tout temps

t \in \mathbb{R}

et qui ont une croissance exponentielle (pour

t\rightarrow −\infty

) dans l'espace de Sobolev

H^{1}

. Dans cet article nous montrons que ces solutions ont aussi une croissance exponentielle (pour

t\rightarrow −\infty

) dans tout espace de Sobolev

H^{m}

(

m⩾2

) à condition que la force soit dans l'espace de Sobolev

H^{m−1}

.
Multi-bump type nodal solutions having a prescribed number of nodal domains: I
Authors: Wang Zhi-Qiang , Liu Zhaoli
Published: April 2005

This paper is concerned with analyzing their nodal property of multi-bump type sign-changing solutions constructed by Coti Zelati and Rabinowitz [Comm. Pure Appl. Math. 45 (1992) 1217]. In some cases we provide both upper and lower bounds on the number of nodal domains for these solutions.

Cet article concerne l'analyse de la propriété nodale des solutions de multi-bosse changeant de signe, construites par Coti Zelati et Rabinowitz [Comm. Pure Appl. Math. 45 (1992) 1217]. Dans certain cas, nous obtenons la borne supérieure et inférieure de nombre des domaines nodales de ces solutions.
Pointwise curvature estimates for F-stable hypersurfaces
Authors: Winklmann Sven
Published: April 2005

We consider immersed hypersurfaces in euclidean

\mathbb{R}^{n + 1}

which are stable with respect to an elliptic parametric functional of the form

\mathcal{F}(X) = \int _{M}F(N)\:\mathrm{d}\mu

. We prove a pointwise curvature estimate provided that

n⩽5

and

F

is sufficiently close to the area integrand. This extends the pointwise curvature estimates of Schoen, Simon and Yau [Acta Math. 134 (1975) 275] for stable minimal hypersurfaces in

\mathbb{R}^{n + 1}

and of Simon [Math. Z. 154 (1977) 265] for minimizers of

\mathcal{F}

. Our result follows from an integral curvature estimate and a generalized Simons inequality that were established recently [Calc. Var. Partial Differential Equations (2004), DOI: 10.1007/S00526-004-0306-5], together with a Moser type iteration argument.

Nous considérons des hypersurfaces dans l'espace euclidien

\mathbb{R}^{n + 1}

qui sont stables par rapport à une fonctionnelle paramétrique elliptique de la forme

\mathcal{F}(X) = \int _{M}F(N)\:\mathrm{d}\mu

. Nous démontrons une estimation ponctuelle de la courbure sous l'hypothèse

n⩽5

et

F

est suffisamment proche de l'intégrande aire. Ce résultat étend l'estimation ponctuelle de la courbure obtenue par Schoen, Simon et Yau [Acta Math. 134 (1975) 275] pour les hypersurfaces minimales stables de

\mathbb{R}^{n + 1}

et par Simon [Math. Z. 154 (1977) 265] pour les minimiseurs de

F

. Une estimation intégrale de la courbure, une inégalité de Simons généralisée, établie récemment dans [Calc. Var. Partial Differential Equations (2004), DOI : 10.1007/S00526-004-0306-5], ainsi qu'un argument itératif de type Moser nous permet d'obtenir cette estimation ponctuelle.
Pharmacological left ventricular reverse remodeling in elderly patients receiving optimal therapy for chronic heart failure
Authors: Cioffi Giovanni , Tarantini Luigi , De Feo Stefania , Pulignano Giovanni , Del Sindaco Donatella , Stefenelli Carlo , Opasich Cristina
Published: April 2005

Background and aims:

In recent years, reversal of established left ventricular (LV) dilatation has been increasingly recognized in middle‐aged patients with dilated cardiomyopathy receiving angiotensin‐converting enzyme (ACE) inhibitors and/or beta‐blockers. We performed this prospective study to evaluate whether optimized therapy for heart failure also induces LV reverse remodeling in older patients.

Methods:

One hundred and twenty‐four patients aged >70 years with LV ejection fraction <40% underwent clinical and echocardiographic evaluation at baseline and after 1 year. During the early stage of follow‐up, pharmacological therapy was optimized. LV reverse remodeling was defined as a reduction in LV end‐diastolic volume >25% from baseline to final evaluation.

Results:

LV reverse remodeling was recognized in 32 patients (26%). Compared to the subjects who did not improve LV geometry, those with reverse remodeling had, at baseline, higher arterial blood pressure, lower serum creatinine levels, shorter duration of symptoms of heart failure, more frequently received beta‐blocker therapy and had predominantly nonischemic aetiology. The variables associated with the development of reverse remodeling in the multivariate analysis were shorter duration of symptoms of heart failure (Odds ratio: 7.7; CI: 2.5–23.3, p=0.0001) and beta‐blocker therapy (Odds ratio: 6.0; CI: 1.6–23.3, p=0.01).

Conclusions:

LV reverse remodeling takes place in elderly as well as in younger heart failure patients. A significant proportion of elderly patients undergoes this favourable process which occurs prevalently in patients receiving beta‐blocker therapy with a short history of cardiac disease.
Beneficial effects of add‐on hydrochlorothiazide in rats with myocardial infarction optimally treated with quinapril
Authors: Westendorp Bart , Schoemaker Regien G. , Buikema Hendrik , de Zeeuw Dick , Boomsma Frans , van Gilst Wiek H. , van Veldhuisen Dirk J.
Published: April 2005

Background:

The antihypertensive and renoprotective effects of ACE inhibitor (ACEi) therapy are enhanced by inducing a negative sodium balance. Whether this strategy also improves outcome of chronic ACEi treatment after myocardial infarction (MI) is unknown. Therefore, we investigated whether hydrochlorothiazide (HCTZ) or dietary sodium restriction further improves survival in ACEi‐treated rats with MI.

Methods:

MI was induced by coronary ligation. After 2 weeks rats were randomised to quinapril (QUI), HCTZ added to quinapril (QUI+HCTZ), or low sodium diet added to quinapril (QUI+LS). Survival was monitored for 62 weeks, after which left ventricular (LV) pressures were measured and blood for neurohumoral characterisation was collected. A separate group of rats, subjected to the same procedure, was evaluated after 35 weeks.

Results:

After 62 weeks, mortality was comparable in all groups. However, survival was improved by HCTZ until 35 weeks. This effect on survival was paralleled by decreased proteinuria and LV end‐diastolic pressures in QUI+HCTZ rats at 35, but not 62 weeks. Plasma renin activity was significantly decreased in QUI+HCTZ rats at 35 weeks. Contrary to HCTZ, LS added to QUI caused no benefit.

Conclusions

Adding HCTZ, but not LS, to quinapril improved survival, neurohumoral status, and proteinuria during the early chronic phase of experimental post‐MI LV dysfunction. Since no adverse effects were observed, HCTZ may safely be used to improve ACEi therapy.
Incident atrial fibrillation and mortality in older adults with heart failure
Authors: Ahmed Ali , Perry Gilbert J.
Published: April 2005

We studied 944 hospitalized heart failure patients 65 years and older to examine the impact of incident atrial fibrillation on mortality. Patients were categorized into four groups based on past medical history and admission electrocardiogram: (1) no (neither past nor current), (2) incident (newly diagnosed), (3) past and (4) chronic (past and current) atrial fibrillation. The primary outcome was 4‐year all‐cause mortality. Bivariate and multivariable Cox proportion hazards analyses were used to determine risk of all‐cause mortality. In the multivariable model, we adjusted for various demographic and clinical covariates. Compared with patients who never had atrial fibrillation, those with incident atrial fibrillation had a 57% higher risk of death (unadjusted hazard ratio, 1.57; 95% confidence interval, 1.22–2.03). After adjustment for other covariates the association remained unchanged (adjusted hazard ratio, 1.41; 95% confidence interval, 1.08–1.83). Past or chronic atrial fibrillation was not associated with increased risk of death.
Pulsed radiofrequency applied to dorsal root ganglia causes a selective increase in ATF3 in small neurons
Authors: Hamann Wolfgang , Abou‐Sherif Sherif , Thompson Stephen , Hall Susan
Published: April 2005

Background This is a “proof of concept study” to test the hypothesis that pulsed radiofrequency, PRF, produces cell stress at the primary afferent level without signs of overt thermal damage. We assumed that cell stress would result in impairment of normal function, and used the expression of activating transcription factor 3, ATF3, as an indicator of cellular “stress”.

Methods PRF (20 ms of 500‐kHz RF pulses, delivered at a rate of 2 Hz; maximum temperature 42 °C) was delivered either to the sciatic nerve of adult rats in mid thigh, or to the L4 anterior primary ramus just distal to the intervertebral foramen. Controls were sham‐operated or L4 axotomised. All tissues were examined 14 days after surgery. The percentage of CGRP‐ or ATF3‐positive DRG neuronal somata was calculated using image analysis software (SigmaScan Pro 4).

Results ATF3 expression was upregulated in L4 DRG neuronal cell bodies, irrespective of their size, after axotomy. It was also upregulated significantly (p < 0.002) and selectively, in small and medium calibre L4 DRG neurons, when PRF was applied close to the DRG just distal to the intervertebral foramen. PRF did not produce any obvious cellular changes in the nerve or L4 DRG neurons when applied to the sciatic nerve in mid‐thigh.

Conclusion PRF has a biological effect, unlikely to be related to overt thermal damage. It appears to be selective in that it targets the group of neurons whose axons are the small diameter C and Aδ nociceptive fibres.
H2O2 activates Nox4 through PLA2‐dependent arachidonic acid production in adult cardiac fibroblasts
Authors: Colston James T. , de la Rosa Sam D. , Strader James R. , Anderson Matthew A. , Freeman Gregory L.
Published: April 2005

Stimulated production of reactive oxygen species (ROS) by plasma membrane‐associated nicotinamide adenine dinucleotide phosphate oxidases (Nox) in non‐phagocytic cells regulates a number of biological processes including growth, vessel tone, and oxygen sensing. The purpose of this study was to investigate H2O2‐stimulated ROS production in primary adult cardiac fibroblasts (CF). Results demonstrate that CF express an H2O2‐inducible oxidant generating system that is inhibitable by diphenylene iodonium (DPI) and sensitive to antioxidants. In addition to H2O2, generation of ROS was stimulated potently by 1‐oleoyl‐2‐acetyl‐sn‐glycerol (OAG) and arachidonic acid (AA) in a protein kinase C‐independent manner. Pretreatment with arachidonyl trifluoromethyl ketone was nearly as effective as DPI at reducing H2O2‐ and OAG‐stimulated oxidant generation indicating a central role for phospholipase A2 (PLA2) in this signaling pathway. Co‐stimulation with H2O2 and OAG did not increase ROS generation as compared to OAG alone suggesting both agonists signal through a shared, rate‐limited enzymatic pathway involving PLA2. Co‐stimulation with H2O2 and AA had additive effects indicating these two agonists stimulate oxidant production through a parallel activation pathway. Reverse transcriptase‐coupled polymerase chain reaction and Western blotting demonstrate primary cardiac fibroblasts express transcripts and protein for Nox4, p22, p47, and p67 phox. Transfections with Nox4 small inhibitory ribonucleic acid oligonucleotides or p22 phox antisense oligonucleotides significantly downregulated stimulated Nox activity. Inhibitors of nitric oxide synthases were without effect. We conclude adult CF express Nox4/p22 phox‐containing oxidant generating complex activated by H2O2, OAG, and AA through a pathway that requires activation of PLA2.
Thermal stability of outer membrane protein porin from Paracoccus denitrificans: FT‐IR as a spectroscopic tool to study lipid–protein interaction
Authors: Sukumaran Suja , Hauser Karin , Rauscher Annette , Mäntele Werner
Published: April 2005

Lipid protein interactions play a key role in the stability and function of various membrane proteins. Earlier we have reported the extreme thermal stability of porin from Paracoccus denitrificans reconstituted into liposomes. Here, we used Fourier transform infrared spectroscopy for a label free analysis of the global secondary structural changes and local changes in the tyrosine microenvironment. Our results show that a mixed lipid system (non‐uniform bilayer) optimizes the thermal stability of porin as compared to the porin in pure lipids (uniform bilayer) or detergent micelles. This is in line with the fact that the bacterial outer membrane is a dynamic system made up of lipids of varying chain lengths, head groups and the barrel wall height contacting the membrane is uneven.
A recombinant diheme SoxAX cytochrome – Implications for the relationship between EPR signals and modified heme‐ligands
Authors: Kappler Ulrike , Hanson Graeme R. , Jones Alun , McEwan Alastair G.
Published: April 2005

The multiheme SoxAX proteins are notable for their unusual heme ligation (His/Cys‐persulfide in the SoxA subunit) and the complexity of their EPR spectra. The diheme SoxAX protein from Starkeya novella has been expressed using Rhodobacter capsulatus as a host expression system. rSoxAX was correctly formed in the periplasm of the host and contained heme c in similar amounts as the native SoxAX. ESI‐MS showed that the full length rSoxA, in spite of never having undergone catalytic turnover, existed in several forms, with the two major forms having masses of 28 687 ± 4 and 28 718 ± 4 Da. The latter form exceeds the expected mass of rSoxA by 31 ± 4 Da, a mass close to that of a sulfur atom and indicating that a fraction of the recombinant protein contains a cysteine persulfide modification. EPR spectra of rSoxAX contained all four heme‐dependent EPR signals (LS1a, LS1b, LS2, LS3) found in the native SoxAX proteins isolated from bacteria grown under sulfur chemolithotrophic conditions. Exposure of the recombinant SoxAX to different sulfur compounds lead to changes in the SoxA mass profile as determined by ESI while maintaining a fully oxidized SoxAX visible spectrum. Thiosulfate, the proposed SoxAX substrate, did not cause any mass changes while after exposure to dimethylsulfoxide a +112 ± 4 Da form of SoxA became dominant in the mass spectrum.
Endosialin (TEM1, CD248) is a marker of stromal fibroblasts and is not selectively expressed on tumour endothelium
Authors: MacFadyen John R. , Haworth Oliver , Roberston David , Hardie Deborah , Webster Marie-Therese , Morris Howard R. , Panico Maria , Sutton-Smith Mark , Dell Anne , van der Geer Peter , Wienke Dirk , Buckley Christopher D. , Isacke Clare M.
Published: April 2005

Fibroblasts are a diverse cell type and display clear topographic differentiation and positional memory. In a screen for fibroblast specific markers we have characterized four monoclonal antibodies to endosialin (TEM1/CD248). Previous studies have reported that endosialin is a tumour endothelium marker and is localized intracellularly. We demonstrate conclusively that endosialin is a cell surface glycoprotein and is predominantly expressed by fibroblasts and a subset of pericytes associated with tumour vessels but not by tumour endothelium. These novel antibodies will facilitate the isolation and classification of fibroblast and pericyte lineages as well as the further functional analysis of endosialin.
Transcriptional regulation of connective tissue growth factor by sphingosine 1‐phosphate in rat cultured mesangial cells
Authors: Katsuma Susumu , Ruike Yoshinao , Yano Takeaki , Kimura Mai , Hirasawa Akira , Tsujimoto Gozoh
Published: April 2005

Connective tissue growth factor (CTGF) is induced by transforming growth factor‐β (TGF‐β) via Smad activation in mesangial cells. We recently reported that sphingosine 1‐phosphate (S1P) induces CTGF expression in rat cultured mesangial cells. However, the mechanism by which S1P induces CTGF expression is unknown. The present study revealed that S1P‐induced CTGF expression is mediated via pertussis toxin‐insensitive pathways, which are involved in the activation of small GTPases of the Rho family and protein kinase C. We also showed by luciferase reporter assays and chromatin immunoprecipitation that S1P induces CTGF expression via Smad activation as TGF‐β does.
The presence of valine at residue 129 in human prion protein accelerates amyloid formation
Authors: Baskakov Ilia , Disterer Petra , Breydo Leonid , Shaw Michael , Gill Andrew , James William , Tahiri-Alaoui Abdessamad
Published: April 2005

The polymorphism at residue 129 of the human PRNP gene modulates disease susceptibility and the clinico‐pathological phenotypes in human transmissible spongiform encephalopathies. The molecular mechanisms by which the effect of this polymorphism are mediated remain unclear. It has been shown that the folding, dynamics and stability of the physiological, α‐helix‐rich form of recombinant PrP are not affected by codon 129 polymorphism. Consistent with this, we have recently shown that the kinetics of amyloid formation do not differ between protein containing methionine at codon 129 and valine at codon 129 when the reaction is initiated from the α‐monomeric PrPC‐like state. In contrast, we have shown that the misfolding pathway leading to the formation of β‐sheet‐rich, soluble oligomer was favoured by the presence of methionine, compared with valine, at position 129. In the present work, we examine the effect of this polymorphism on the kinetics of an alternative misfolding pathway, that of amyloid formation using partially folded PrP allelomorphs. We show that the valine 129 allelomorph forms amyloids with a considerably shorter lag phase than the methionine 129 allelomorph both under spontaneous conditions and when seeded with pre‐formed amyloid fibres. Taken together, our studies demonstrate that the effect of the codon 129 polymorphism depends on the specific misfolding pathway and on the initial conformation of the protein. The inverse propensities of the two allelomorphs to misfold in vitro through the alternative oligomeric and amyloidogenic pathways could explain some aspects of prion diseases linked to this polymorphism such as age at onset and disease incubation time.
The Prevalence of Wrist Ganglia in an Asymptomatic Population: Magnetic Resonance Evaluation
Authors: LOWDEN C. M. , ATTIAH M. , GARVIN G. , MACDERMID J. C. , OSMAN S. , FABER K. J.
Published: April 2005

Magnetic resonance imaging (MRI) was performed on the wrists of 103 asymptomatic volunteers. The images were evaluated independently by two musculoskeletal radiologists and one orthopaedic surgeon. Wrist ganglia were identified in 53 out of the 103 wrists. The average long and short axes measurements were 8 mm (range 3–22) and 3 mm (range 2–10), respectively. Seventy per cent of the ganglia originated from the palmar capsule in the region of the interval between the radioscaphocapitate ligament and the long radiolunate ligament. Fourteen per cent of the ganglia were dorsal and originated from the dorsal, distal fibres of the scapholunate ligament. Two ganglia had surrounding soft tissue oedema and one had an associated intraosseous component. Unlike previous surgical and pathological series, our study showed that palmar wrist ganglia are more common than dorsal wrist ganglia. The vast majority of these asymptomatic ganglia occur without associated ligamentous disruption, soft tissue oedema or intraosseous communication.
TORTS, A EUROPEAN IUS COMMUNE AND THE PRIVATE ENFORCEMENT OF COMMUNITY LAW
Authors: Betlem Gerrit
Published: April 2005

THERE is a lively debate among scholars in Europe about how, if at all, the private laws (tort, contract, property) of the European nation states should be harmonised. Views range from no harmonisation at all, soft law methods such as models contained in Principles, step by step case law developments, to a fully fledged binding European Civil Code. Another hotly debated issue is the disharmonisation (fragmentation) of domestic systems of private law as a result of current and ongoing EC level harmonisation. The prime consequence of this partial legislative intervention is an enhanced role for the judiciaries of those jurisdictions: they are inevitably entrusted with the fine-tuning of the interaction between domestic and EC private law. Alien concepts make their entry into a Member State’s Civil Code or common law doctrine that do not necessarily easily fit (one scholar has called these “legal irritants”). Most likely, for the foreseeable future, piecemeal harmonisation of specific, and more or less narrow, legal fields is the only show in town.
Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity
Authors: Notholt J. , Luo B. P. , Fueglistaler S. , Weisenstein D. , Rex M. , Lawrence M. G. , Bingemer H. , Wohltmann I. , Corti T. , Warneke T. , von Kuhlmann R. , Peter T.
Published: April 2005

Stratospheric water vapor plays an important role in the chemistry and radiation budget of the stratosphere. Throughout the last decades stratospheric water vapor levels have increased and several processes have been suggested to contribute to this trend. Here we present a mechanism that would link increasing anthropogenic SO2 emissions in southern and eastern Asia with an increase in stratospheric water. Trajectory studies and model simulations suggest that the SO2 increase results in the formation of more sulfuric acid aerosol particles in the upper tropical troposphere. As a consequence, more ice crystals of smaller size are formed in the tropical tropopause, which are lifted into the stratosphere more readily. Our model calculations suggest that such a mechanism could increase the amount of water that entered the stratosphere in the condensed phase by up to 0.5 ppmv from 1950–2000.
Longitudinal variability of water vapor and cirrus in the tropical tropopause layer
Authors: Clark H. L.
Published: April 2005

The Microwave Limb Sounder (MLS) and the Cryogenic Limb Array Etalon Spectrometer (CLAES) are both instruments on the Upper Atmosphere Research Satellite and are sensitive to water vapor and subvisible cirrus in the tropical tropopause layer. We analyze the longitudinal and vertical variations of water vapor in the tropical tropopause layer using a new version of MLS water vapor that has improved vertical resolution. The water vapor fields show similarity with subvisible cirrus and sea surface temperature (SST) on seasonal and intraseasonal timescales. The formation of cirrus is more prevalent over continental landmasses and over warm oceanic areas where the upper troposphere is also moist. The intraseasonal variability in cirrus is correlated with upper tropospheric water vapor and linked to a variability in SST of about 1°C. The incidence of cirrus increases with SST until temperatures exceed about 29°C. A further rise in sea surface temperature does not see a corresponding increase in cirrus. Similarly, the incidence of cirrus increases as 100 hPa temperatures fall, with clouds being more likely when temperatures are about 190K. At temperatures colder than this, when in situ formation of cirrus should be more likely, there is a decrease in the likelihood of finding cirrus. Thus evidence points strongly to a dominant role for the convective formation of these cirrus.