bluuebunny/crossref_metadata_2025 huggingface dataset:
Pyroglutamylated RFamide Peptide 43 Stimulates the Hypothalamic-Pituitary-Gonadal Axis via Gonadotropin-Releasing Hormone in Rats
Authors: Patel Sejal R. , Murphy Kevin G. , Thompson Emily L. , Patterson Michael , Curtis Annette E. , Ghatei Mohammad A. , Bloom Stephen R.
Published: June 2008

Although it is established that other members of the RFamide family stimulate the hypothalamic-pituitary-gonadal axis, the influence of the novel pyroglutamylated RFamide peptide 43 (QRFP43) is not known. We show intracerebroventricular (icv) administration of QRFP43 (2 nmol) to male rats increased plasma LH and FSH levels at 40 min after injection. icv administration of 3 nmol QRFP43 did not affect food intake in ad-libitum-fed male rats. The icv administration of 2 nmol QRFP43 did not significantly influence behavior in male rats. Intraperitoneal administration of doses up to 1200 nmol/kg QRFP43 in male rats did not significantly influence circulating gonadotropin or sex steroid levels. In vitro, QRFP43 stimulated GnRH release from hypothalamic explants from male rats and from GT1-7 cells. Pretreatment with a GnRH receptor antagonist, cetrorelix, blocked the increase in plasma LH levels after icv administration of QRFP43 (2 nmol). These results suggest that icv QRFP43 activates the hypothalamic-pituitary-gonadal axis via GnRH.
Regulation of Prostatic Stem Cells by Stromal Niche in Health and Disease
Authors: Risbridger Gail P. , Taylor Renea A.
Published: June 2008

The isolation and characterization of prostatic stem cells has received significant attention in the last few years based on the belief that aberrant regulation of adult stem cells leads to prostate disease including cancer. The nature of the perturbations in stem cell regulation remains largely unknown. Although adult stem cells are can be governed by autonomous regulatory mechanisms, the stromal niche environment also provides essential cues to direct directing differentiation decisions and can lead to aberrant proliferation and/or differentiation. Elegant tissue recombination experiments, pioneered by Gerald Cunha and colleagues, provided evidence that quiescent epithelial tissues containing adult stem cells were capable of altered differentiation in response to inductive and instructive mesenchyme. In more recent times, it has been demonstrated that embryonic mesenchyme is sufficiently powerful to direct the differentiation of embryonic stem cells into mature prostate or bladder. In addition, prostatic tumor stroma provides another unique niche or microenvironment for stem cell differentiation that is distinct to normal stroma. This review highlights the importance of the appropriate selection of the stromal cell niche for tissue regeneration and implies plasticity of adult stem cells that is dictated by the tissue microenvironment.
LKB1 in endothelial cells is required for angiogenesis and TGFβ-mediated vascular smooth muscle cell recruitment
Authors: Londesborough Anou , Vaahtomeri Kari , Tiainen Marianne , Katajisto Pekka , Ekman Niklas , Vallenius Tea , Mäkelä Tomi P.
Published: June 2008

Inactivation of the tumor suppressor kinase Lkb1 in mice leads to vascular defects and midgestational lethality at embryonic day 9-11 (E9-E11). Here, we have used conditional targeting to investigate the defects underlying the Lkb1-/- phenotype. Endothelium-restricted deletion of Lkb1 led to embryonic death at E12.5 with a loss of vascular smooth muscle cells (vSMCs) and vascular disruption. Transforming growth factor beta(TGFβ) pathway activity was reduced in Lkb1-deficient endothelial cells (ECs), and TGFβ signaling from Lkb1-/- ECs to adjacent mesenchyme was defective, noted as reduced SMAD2 phosphorylation. The addition of TGFβ to mutant yolk sac explants rescued the loss of vSMCs, as evidenced by smooth muscle alpha actin(SMA) expression. These results reveal an essential function for endothelial Lkb1 in TGFβ-mediated vSMC recruitment during angiogenesis.
Sonic hedgehog signalling from foregut endoderm patterns the avian nasal capsule
Authors: Benouaiche Laurence , Gitton Yorick , Vincent Christine , Couly Gérard , Levi Giovanni
Published: June 2008

Morphogenesis of the facial skeleton depends on inductive interactions between cephalic neural crest cells and cephalic epithelia, including the foregut endoderm. We show that Shh expression in the most rostral zone of the endoderm, endoderm zone I (EZ-I), is necessary to induce the formation of the ventral component of the avian nasal capsule: the mesethmoid cartilage. Surgical removal of EZ-I specifically prevented mesethmoid formation, whereas grafting a supernumerary EZ-I resulted in an ectopic mesethmoid. EZ-I ablation was rescued by Shh-loaded beads, whereas inhibition of Shh signalling suppressed mesethmoid formation. This interaction between the endoderm and cephalic neural crest cells was reproduced in vitro,as evidenced by Gli1 induction. Our work bolsters the hypothesis that early endodermal regionalisation provides the blueprint for facial morphogenesis and that its disruption might cause foetal craniofacial defects,including those of the nasal region.
Turning neurons into a nervous system
Authors: Grove Elizabeth A.
Published: June 2008

The RIKEN Center for Developmental Biology recently held its 2008 Symposium`Turning Neurons into a Nervous System' in Kobe, Japan. The program, organized by Masatoshi Takeichi, Joshua Sanes, Hideki Enomoto and Raj Ladher, provided a rich sampling from current work in developmental neurobiology. Researchers from Japan, Europe and the USA gathered at this meeting to share insights into neural development and to admire the opening of the cherry blossom season.
A Computational Analysis of Linear Price Iterative Combinatorial Auction Formats
Authors: Bichler Martin , Shabalin Pasha , Pikovsky Alexander
Published: June 2008

Iterative combinatorial auctions (ICAs) are IT-based economic mechanisms where bidders submit bundle bids in a sequence and an auctioneer computes allocations and ask prices in each auction round. The literature in this field provides equilibrium analysis for ICAs with nonlinear personalized prices under strong assumptions on bidders' strategies. Linear pricing has performed very well in the lab and in the field. In this paper, we compare three selected linear price ICA formats based on allocative efficiency and revenue distribution using different bidding strategies and bidder valuations. The goal of this research is to benchmark different ICA formats and design and analyze new auction rules for auctions with pseudodual linear prices. The multi-item and discrete nature of linear price iterative combinatorial auctions and the complex price calculation schemes defy much of the traditional game theoretical analysis in this field. Computational methods can be of great help in exploring potential auction designs and analyzing the virtues of various design options. In our simulations, we found that ICA designs with linear prices performed very well for different valuation models even in cases of high synergies among the valuations. There were, however, significant differences in efficiency and in the revenue distributions of the three ICA formats. Heuristic bidding strategies using only a few of the best bundles also led to high levels of efficiency. We have also identified a number of auction rules for ask price calculation and auction termination that have shown to perform very well in the simulations.
Treatment of intra-articular fractures of the distal radius
Authors: Varitimidis S. E. , Basdekis G. K. , Dailiana Z. H. , Hantes M. E. , Bargiotas K. , Malizos K.
Published: June 2008

In a randomised prospective study, 20 patients with intra-articular fractures of the distal radius underwent arthroscopically- and fluoroscopically-assisted reduction and external fixation plus percutaneous pinning. Another group of 20 patients with the same fracture characteristics underwent fluoroscopically-assisted reduction alone and external fixation plus percutaneous pinning. The patients were evaluated clinically and radiologically at follow-up of 24 months. The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and modified Mayo wrist score were used at 3, 9, 12 and 24 months postoperatively. In the arthroscopically- and fluoroscopically-assisted group, triangular fibrocartilage complex tears were found in 12 patients (60%), complete or incomplete scapholunate ligament tears in nine (45%), and lunotriquetral ligament tears in four (20%). They were treated either arthroscopically or by open operation. Patients who underwent arthroscopically- and fluoroscopically-assisted treatment had significantly better supination, extension and flexion at all time points than those who had fluoroscopically-assisted surgery. The mean DASH scores were similar for both groups at 24 months, whereas the difference in the mean modified Mayo wrist scores remained statistically significant.

Although the groups are small, it is clear that the addition of arthroscopy to the fluoroscopically-assisted treatment of intra-articular distal radius fractures improves the outcome. Better treatment of associated intra-articular injuries might also have been a reason for the improved outcome.
Strain imparted during impaction grafting may contribute to bony incorporation
Authors: Board T. N. , Rooney P. , Kay P. R.
Published: June 2008

In order to investigate the osteoinductive properties of allograft used in impaction grafting and the effect of strain during impaction on these properties, we designed an in vitro experiment to measure strain-related release of bone morphogenetic protein-7 (BMP-7) from fresh-frozen femoral head allograft. A total of 40 10 mm cubes of cancellous bone were cut from ten samples of fresh-frozen femoral head. The marrow was removed from the cubes and the baseline concentrations of BMP-7 were measured. Specimens from each femoral head were allocated to four groups and subjected to different compressive strains with a material testing machine, after which BMP-7 activity was reassessed. It was present in all groups. There was a linear increase of 102.1 pg/g (95% confidence interval 68.6 to 135.6) BMP-7 for each 10% increase in strain. At 80% strain the mean concentration of BMP-7 released (830.3 pg/g bone) was approximately four times that released at 20% strain. Activity of BMP-7 in fresh-frozen allograft has not previously been demonstrated. This study shows that the freezing and storage of femoral heads allows some maintenance of biological activity, and that impaction grafting provides a source of osteoinductive bone for remodelling.

We have shown that BMP-7 is released from fresh-frozen femoral head cancellous bone in proportion to the strain applied to the bone. This suggests that the impaction process itself may contribute to the biological process of remodelling and bony incorporation.
Evaluation of two surgical techniques for acetabular reconstruction in total hip replacement for congenital hip disease
Authors: Hartofilakidis G. , Georgiades G. , Babis G. C. , Yiannakopoulos C. K.
Published: June 2008

We have evaluated the results of total hip replacement in patients with congenital hip disease using 46 cemented all-polyethylene Charnley acetabular components implanted with the cotyloplasty technique in 34 patients (group A), and compared them with 47 metal-backed cementless acetabular components implanted without bone grafting in 33 patients (group B). Patients in group A were treated between 1988 and 1993 and those in group B between 1990 and 1995. The mean follow-up for group A was 16.6 years (12 to 18) and the mean follow-up for group B was 13.4 years (10 to 16).

Revision for aseptic loosening was undertaken in 15 hips (32.6%) in group A and in four hips (8.5%) in group B. When liner exchange was included, a total of 13 hips were revised in group B (27.7%). The mean polyethylene wear was 0.11 mm/yr (0.002 to 0.43) and 0.107 mm/yr (0 to 0.62) for groups A and B, respectively. Polyethylene wear in group A was associated with linear osteolysis, and in group B with expansile osteolysis.

In patients with congenital hip disease, when 80% cover of the implant can be obtained, a cementless acetabular component appears to be acceptable and provides durable fixation. However, because of the type of osteolysis arising with these devices, early exchange of a worn liner is recommended before extensive bone loss makes revision surgery more complicated.
Tribological and material analyses of retrieved alumina and zirconia ceramic heads correlated with polyethylene wear after total hip replacement
Authors: Kim Y.-H. , Kim J.-S.
Published: June 2008

It has been suggested that the wear of ultra-high molecular weight polyethylene (UHMWPE) in total hip replacement is substantially reduced when the femoral head is ceramic rather than metal. However, studies of alumina and zirconia ceramic femoral heads on the penetration of an UHMWPE liner in vivo have given conflicting results.

The purpose of this study was to examine the surface characteristics of 30 alumina and 24 zirconia ceramic femoral heads and to identify any phase transformation in the zirconia heads. We also studied the penetration rate of alumina and zirconia heads into contemporary UHMWPE liners. The alumina heads had been implanted for a mean of 11.3 years (8.1 to 16.2) and zirconia heads for a mean of 9.8 years (7.5 to 15).

The mean surface roughness values of the explanted alumina heads (Ra 40.12 nm and Rpm 578.34 nm) were similar to those for the explanted zirconia heads (Ra 36.21 nm and Rpm 607.34 nm). The mean value of the monoclinic phase of two control zirconia heads was 1% (0.8% to 1.5%) and 1.2% (0.9% to 1.3%), respectively. The mean value of the monoclinic phase of 24 explanted zirconia heads was 7.3% (1% to 26%).

In the alumina group, the mean linear penetration rate of the UMWPE liner was 0.10 mm/yr (0.09 to 0.12) in hips with low Ra and Rpm values (13.22 nm and 85.91 nm, respectively). The mean linear penetration rate of the UHMWPE liner was 0.13 mm/yr (0.07 to 0.23) in hips with high Ra and Rpm values (198.72 nm and 1329 nm, respectively). This difference was significant (p = 0.041).

In the zirconia head group, the mean linear penetration rate of the UHMWPE liner was 0.09 mm/yr (0.07 to 0.14) in hips with low Ra and Rpm values (12.78 nm and 92.99 nm, respectively). The mean linear penetration rate of the UHMWPE liner was 0.12 mm/yr (0.08 to 0.22) in hips with high Ra and Rpm values (199.21 nm and 1381 nm, respectively). This difference was significant (p = 0.039).

The explanted zirconia heads which had a minimal phase transformation had similar surface roughness and a similar penetration rate of UHMWPE liner as the explanted alumina head.
Through the Lens of a Neighbor: Perceptions of Mexican Educators and Students regarding Current United States Policies
Authors: Cashman Timothy G. , Rubio Rene A.
Published: June 2008

Researchers analyzed the perceptions and pedagogies of educators in two Chihuahua, Mexico, public schools with regard to United States foreign policies. The key objective of the research was to provide additional insight into the impact of recent actions taken by the United States Government, including the war in Iraq. Chihuahuan educators and their students suggested that the United States Government should be more engaged in the dialogue of how to address the root causes of terrorism. Additionally, the findings of this study indicated that educators and future teachers in both the United States and Mexico benefit from broader understandings of educators' roles and students' perceptions in a binational community.
Exclusion of Polymorphisms in Carnosinase Genes (CNDP1 and CNDP2) as a Cause of Diabetic Nephropathy in Type 1 Diabetes
Authors: Wanic Krzysztof , Placha Grzegorz , Dunn Jonathon , Smiles Adam , Warram James H. , Krolewski Andrzej S.
Published: June 2008

OBJECTIVES— Recently, an association was found between diabetic nephropathy and the D18S880 microsatellite, located in the carnosinase gene (CNDP1) on chromosome 18q. Alleles of this microsatellite encode for a variable number of leucine residues (from four to seven) in the leader peptide of the carnosinase precursor. The frequency of subjects homozygous for the five leucines was higher in control subjects than in case subjects in studies focusing on type 2 diabetic patients. To test whether this finding can be extended to type 1 diabetic patients, we carried out a comprehensive study on association between diabetic nephropathy and the D18S880 microsatellite and 21 additional SNPs that tagged the genomic region containing CNDP1 and CNDP2.

RESEARCH DESIGN AND METHODS— Overall, 1,269 Caucasian patients with type 1 diabetes were included in the study, including 613 patients with normoalbuminuria and a long duration of diabetes, 445 patients with persistent proteinuria, and 211 patients with end-stage renal disease (ESRD). All patients were genotyped for selected polymorphisms, the associations with diabetic nephropathy were tested by a χ2 test, and odds ratios were calculated.

RESULTS— We did not find any significant association between diabetic nephropathy and any examined genetic markers. The negative findings of the case-control study were supported further by negative findings obtained from the 6-year follow-up study of 445 patients with persistent proteinuria, during which 135 patients developed ESRD.

CONCLUSIONS— Our large, comprehensive study did not find an association between the D18S880 microsatellite or any other polymorphisms in the CNDP2–CNDP1 genomic region and susceptibility for diabetic nephropathy in type 1 diabetes.
ipso-Substitution – A Novel Pathway for Microbial Metabolism of Endocrine-Disrupting 4-Nonylphenols, 4-Alkoxyphenols, and Bisphenol A
Authors: Kohler Hans-Peter E. , Gabriel Frédéric L. P. , Giger Walter
Published: June 2008

Our studies with Sphingobium xenophagum Bayram show that this bacterial strain degrades ?-quaternary 4-nonylphenols by an ipso-substitution mechanism, whereby the nonylphenol substrates are initially hydroxylated at the ipso position to form 4-hydroxy-4-nonylcyclohexa-2,5-dienones
(quinols). Subsequently, the ?-quaternary side chains are able to detach as short-living cations from these intermediates. Alkyl branches attached to the carbocation help to delocalize and thereby stabilize the positive charge through inductive and hyperconjugative effects, which explains
why only alkyl moieties of ?-quaternary nonylphenols are released. This view is corroborated by experiments with S. xenophagum Bayram, in which the alkyl chains of the non-?-quaternary 4-(1-methyloctyl) phenol (4-NP2) and 4-n-nonylphenol (4-NP1)
were not released, so that the bacterium was unable to utilize these isomers as growth substrates. Analysis of dead end metabolites and experiments with 18O labeled H2O and O2 clearly show that in the main degradation pathway the nonyl cation derived from ?-quaternary
quinols preferentially combines with a molecule of water to yield the corresponding alcohol and hydroquinone. However, the incorporation of significant amounts of O2-derived oxygen into the nonanol metabolites derived from degradation of certain ?,?-dimethyl substituted
nonylphenols by strain Bayram strongly indicates the existence of a minor pathway in which the cation undergoes an alternative reaction and attacks the ipso-hydroxy group, yielding a 4-alkoxyphenol as an intermediate. Additional growth experiments with strain Bayram revealed that also
the two alkoxyphenols 4-tert-butoxyphenol and 4-n-octyloxyphenol promote growth. Furthermore, strain Bayram's ipso-hydroxlating activity is able to transform also bisphenol A.
Genetic Reprogramming of Human Mammary Cells by Environmental Carcinogens Released into Breast Milk
Authors: Dip Ramiro , Buterin Tonko , Wenger Daniela , Schmid Peter , Naegeli Hanspeter
Published: June 2008

Epidemiologic studies indicate that high serum levels of chlorinated pollutants such as dioxins or pesticides constitute a risk factor for breast cancer in postmenopausal women. This finding has been attributed to the ability of organochlorine compounds to induce the expression of cytochrome
P450 (CYP) enzymes, which are thought to increase the burden of genotoxic metabolites. However, it was not clear whether the incriminated pollutants accumulate to sufficiently high levels within the human body to be able to promote significant transcriptional responses. Here, milk samples
from nursing mothers were processed by gel permeation chromatography to isolate complex mixtures of residues containing both endogenous hormones and lipophilic contaminants of environmental origin. High-density oligonucleotide microarrays were used to monitor global transcriptional profiles
in a human cell line (MCF7) that represents one of the most frequently used model systems to study breast cancer biology. We found that all breast milk extracts were able to reprogram the genome of MCF7 cells by imposing a typically estrogenic expression fingerprint. This estrogenic background
was overlapped only by the induction of transcripts coding for CYP1A1 and, to a minor degree, CYP1B1. The magnitude of induction of these metabolic enzymes correlated with the respective organochlorine concentrations. Thus, in support of previous epidemiologic studies, we demonstrate
that contaminants released from human adipose tissue trigger a potentially genotoxic pathway in cells from the mammary gland.
Integrative Risk Assessment of Endocrine Disruptors in Switzerland
Authors: Gälli René , Braun Christian
Published: June 2008

The objective of the project was to develop an environmental fate model for various substances with endocrine-disrupting potential for the Glattal/Greifensee region in Switzerland and to assess the concentration levels. The model provides an estimate of environmental concentrations
based on mass flow calculations from the source of the emissions to the final fate in the environmental compartments. Based on the chemical properties of 20 substances studied in the NRP50 program, the estimated quantities of the substances used and their respective applications, the model
predicts mass flows on a local level. Taking into account the respective water flows, these mass flows result in predicted environmental concentrations in surface water and groundwater. These concentrations can be interpreted as averaged levels with geographical resolution in the local scenario.
The estrogenic equivalent concentration was assessed by estrogenic equivalence factor-weighted addition of the individual substance concentrations for four different toxicological endpoints. From the 20 substances modelled in this project only a few substantially contribute to the overall
endocrine disruption potential. For three of the endpoints used the steroid hormones dominate the endocrine potential. Only the application of the yeast estrogen system (YES) assay predicts a dominant endocrine potential for the degradation products of nonylphenol-poly-ethoxylates (NPnEO)
in the year 2004, which was expected to decrease significantly in the year 2007 due to new legislation (almost complete application ban of NPnEO-based detergents as of August 2006). On the basis of the model's geographical resolution it is possible to identify 'hot spots' in terms of high
endocrine-disruption potential in the modelled region. For the densely populated and industrialised Glattal/Greifensee region sewage treatment plants discharging into relatively small receiving water systems show the highest endocrine disruption potential (estradiol equivalence concentration
of up to 2 ng/l for the vitellogenin synthesis induction endpoint). In addition to modelling the status quo with respect to endocrine disruption possible future risk reduction measures have been assessed for one identified hot-spot. Whereas an increase in sludge retention time in the existing
STP had a moderate effect on the overall endocrine potential, an additional ozonation step showed significant reduction for most endocrine-disrupting substances.
Nanoparticulate Systems: A New Competence Platform at the University of Applied Sciences Northwestern Switzerland (FHNW)
Authors: Shahgaldian Patrick , Wirth Amina , Pieles Uwe
Published: June 2008

Nanotechnology in general and nanoparticles in particular are receiving increasing attention because of their almost unlimited possibilities and applications. In the group of Nanotechnology of the Institute of Chemistry and Bioanalytics of the University of Applied Sciences Northwestern
Switzerland (Fachhochschule Nordwest-schweiz), a new nanoparticle technology platform has been developed. The main research axes concern silica and self-assembled nanoparticles, and their applications in life sciences. The laboratory is equipped with state-of-the-art spectroscopy and microscopy
tools.
Individual Dissolution of Single‐Walled Carbon Nanotubes by Using Polybenzimidazole, and Highly Effective Reinforcement of Their Composite Films
Authors: Okamoto Minoru , Fujigaya Tsuyohiko , Nakashima Naotoshi
Published: June 2008

Polybenzimidazole (PBI) is shown to individually dissolve/disperse single‐walled carbon nanotubes (SWNTs) in N,N‐dimethylacetamide (DMAc), which is demonstrated by vis‐near IR absorption and photoluminescence spectroscopy and atomic force microscopy observations. By casting these dispersions, SWNTs/PBI composite films were successfully fabricated on substrates without any sign of macroscopic aggregation. The thermal stability and mechanical properties of the composite films were investigated using thermogravimetric analysis (TGA) and tensile tests, respectively, and it was found that, first, the addition of SWNTs to PBI does not deteriorate the thermal stability of the matrix film, and second, the mechanical properties of the PBI film were reinforced by ca. 50% with only 0.06 wt % addition of the SWNTs to the film without reducing the thermal stability of the PBI. Raman spectroscopy of the composite films revealed the existence of an interaction between the PBI and the SWNTs. The individual dissolution of the SWNTs and efficient reinforcement of the PBI are due to the π–π interaction between the PBI and the sidewalls of the SWNTs.
Effect of polymer properties on bubble growth in polymer–paperboard composites
Authors: Annapragada Sriram K. , Patterson Timothy F. , Banerjee Sujit
Published: June 2008

Foamed paperboard is a composite material used in thermally insulated food packaging and beverage containers. The paperboard is sandwiched between a layer of low‐density polyethylene and a barrier layer, and the low‐density film is foamed through heating. The moisture inside the paperboard vaporizes and serves as the driving force for creating the foam. The bubble growth on the paper surface has been tracked with high‐speed photography. The number of generated bubbles has been found to depend on the number of pores on the surface of the paperboard; there is little or no dependence on the properties of the polymer, at least across the range of properties studied. In contrast, the thickness of the foam is relatively insensitive to the paperboard properties but has a strong dependence on the thickness of the initial polymer film, the nature of the polymer, and the speed at which it is extruded onto the paperboard. It is believed that some of these variations arise from differences in the degree of adhesion between the polymer and the paperboard. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Structure and mechanical properties of blends of poly(ε‐caprolactone) with a poly(amino ether)
Authors: Granado Ainhoa , Eguiazábal Jose I. , Nazábal Jon
Published: June 2008

Poly(ε‐caprolactone) (PCL)/poly(amino ether) (PAE) blends were obtained by injection molding without any previous extrusion step in an attempt to (i) contribute to the knowledge of the relation between structure and mechanical properties in these type of blends composed of a rubbery and a glassy polymer and (ii) to find out to which extent are the PCL/PAE blends compatible, and therefore whether the biodegradability of PCL can be added as a characteristic of PAE‐based applications. PCL/PAE blends are composed of a crystalline PCL phase, a pure amorphous PCL phase, and a PAE‐rich phase where some PCL is present. The presence of some dissolved and probably unreacted PCL in the PAE‐rich phase led to a low interfacial tension as observed by the small size of the dispersed particles and the large interfacial area. The dependence on composition of both the modulus of elasticity and the yield stress of the blends was parallel to that of the orientation level. The elongation at break showed values similar to those of PAE in PAE‐rich blends, and was slightly synergistic in very rich PCL compositions; this behavior reflects a change in the nature of the matrix, from glassy to rubbery. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Letter to the Editor
Authors: Klæboe R.
Published: June 2008

Article: http://dx.doi.org/10.1002/bimj.200410172

Author reply: http://dx.doi.org/10.1002/bimj.200710417
Synthesis, characterization, and DNA‐binding of chiral complexes Δ‐ and Λ‐[Ru(bpy)2(pyip)]2+
Authors: Shi Shuo , Yao Tian‐Ming , Geng Xiao‐Ting , Jiang Ling‐Feng , Liu Jie , Yang Qing‐Yuan , Ji Liang‐Nian
Published: June 2008

New chiral Ru(II) complexes Δ and Λ‐[Ru(bpy)2(pyip)](PF6)2 [(bpy = 2,2′‐bipyridine; pyip = (2‐(1‐pyrenyl)‐1H‐imidazo[4,5‐f] [1,10]phenanthroline] were synthesized and characterized by elemental analysis, 1H NMR, ESI‐MS, IR, and CD spectra. Their DNA‐binding properties were studied by means of UV–vis, emission spectra, CD spectra and viscosity measurements. A subtle but detectable difference was observed in the interaction of both enantiomer with CT‐DNA. Spectroscopy experiments indicated that each of these complexes could interact with the DNA. The DNA‐binding of the Δ‐enantiomer was stronger than that of Λ‐enantiomer. DNA‐viscosity experiments provided evidence that both Δ‐ and Λ‐[Ru(bpy)2(pyip)](PF6)2 bound to DNA by intercalation. At the same time, the DNA‐photocleavage properties of the complexes were investigated too. Under irradiation with UV light, Ru(II) complexes showed different efficiency of cleaving DNA. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Does life originate from a single molecule?
Authors: Fuß Werner
Published: June 2008

Life did not emerge in a single step. In chemical evolution, the first formation of a self‐replicating molecule was probably one of the most critical bottlenecks, which was overcome only with a very low probability. If only one such event was successful, present‐day life originates from a single molecule. In this case, homochirality in DNA and RNA is explained almost without further assumptions. By contrast, the enantiomer excess, produced by the deterministic mechanisms suggested so far, is smaller than the statistical standard deviation, unless the postulated initial number of molecules is very—in some mechanisms unreasonably—large. A certain chiral nonuniformity of natural monosaccharides other than (deoxy)ribose supports the idea that homochirality originates not from such small molecules but from an early RNA‐like oligomer. This nonuniformity seems also hard to explain by any deterministic mechanism. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Highly enantioselective addition of terminal alkynes to aldehydes catalyzed by a new chiral β‐sulfonamide alcohol/Ti(OiPr)4/Et2Zn/R3N catalyst system
Authors: Qiu Li , Wang Quan , Lin Li , Liu Xiaodong , Jiang Xianxing , Zhao Qingyang , Hu Guowen , Wang Rui
Published: June 2008

A new catalytic system, generated from the readily available and inexpensive β‐sulfonamide alcohol L*, Ti(OiPr)4, Et2Zn, and tertiary amine base (R3N), effectively catalyzes the enantioselective addition of various terminal alkynes including some quite challenging alkynes to aldehydes in good yields and excellent enantioselectivities. Up to 96% yield and >99% enantioselectivity were achieved with the use of N,N‐diisoproylethylamine (DIPEA) as an additive in this asymmetric addition. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Design and implementation of parallel approximate inverse classes using OpenMP
Authors: Giannoutakis Konstantinos M. , Gravvanis George A.
Published: June 2008

A new parallel normalized optimized approximate inverse algorithm, based on the concept of antidiagonal wave pattern, for computing classes of explicitly approximate inverses, is introduced for symmetric multiprocessor systems. The parallel normalized explicit approximate inverses are used in conjunction with parallel normalized explicit preconditioned conjugate gradient schemes for the efficient solution of finite element sparse linear systems. The parallel design and implementation issues of the new algorithm are discussed and the parallel performance is presented using OpenMP. Copyright © 2008 John Wiley & Sons, Ltd.
RAVE: the resource‐aware visualization environment
Authors: Grimstead I. J. , Avis N. J. , Walker D. W.
Published: June 2008

We present the resource‐aware visualization environment (RAVE) project, from its inception and design phases, through implementation choices and final actual use cases. RAVE is a distributed, collaborative Grid‐enabled visualization environment that supports automated resource discovery across heterogeneous machines. RAVE runs as a background process using Web services, enabling us to share resources with other users rather than commandeering an entire machine. RAVE supports a wide range of machines, from hand‐held PDAs to high‐end servers with large‐scale stereoscopic, tracked displays. The local display device may render all, some or none of the data set remotely, depending on its capability and present loading, utilizing remote servers to assist where necessary. This enables scientists and engineers to collaborate from their desks, in the field, or in front of specialized immersive displays. Copyright © 2008 John Wiley & Sons, Ltd.
The Neutralizer: a self‐configurable failure detector for minimizing distributed storage maintenance cost
Authors: Yang Zhi , Dai Yafei , Li Xiaoming
Published: June 2008

To achieve high data availability or reliability in an efficient manner, distributed storage systems must detect whether an observed node failure is permanent or transient, and if necessary, generate replicas to restore the desired level of replication. Given the unpredictability of network dynamics, however, distinguishing permanent and transient failures is extremely difficult. Though timeout‐based detectors can be used to avoid mistaking transient failures as permanent failures, it is unknown how the timeout values should be selected to achieve a better tradeoff between detection latency and accuracy. In this paper, we address this fundamental tradeoff from several perspectives. First, we explore the impact of different timeout values on maintenance cost by examining the probability of their false positives and false negatives. Second, we propose a self‐configurable failure detector called the Neutralizer based on the idea of counteracting false positives with false negatives. The Neutralizer could enable the system to maintain a desired replication level on average with the least amount of bandwidth. We conduct extensive simulations using real trace data from a widely deployed peer‐to‐peer system and synthetic traces based on PlanetLab and Microsoft PCs, showing a significant reduction in aggregate bandwidth usage after applying the Neutralizer (especially in an environment with a low average node availability). Overall, we demonstrate that the Neutralizer closely approximates the performance of a perfect ‘oracle’ detector in many cases. Copyright © 2008 John Wiley & Sons, Ltd.
Time trends in obesity and eating disorders
Authors: Zachrisson Henrik Daae , Vedul‐Kjelsås Einar , Götestam K. Gunnar , Mykletun Arnstein
Published: June 2008

Objective:

Obesity is a well‐known risk factor for eating disorders, and has been increasing in the normal population over the last decades. This study examines whether the increase in obesity is followed by an increase in prevalence of eating disorders in the general female population.

Method:

We compared the prevalence of eating disorders and obesity in two nationally representative surveys in Norway in 1991 (n = 1,537) and 2004 (n = 1,467). Eating disorder diagnoses were obtained using the self‐report questionnaire survey for eating disorders (SEDs) at both time points.

Results:

The prevalence of overweight and obesity has doubled from 1991 to 2004, whereas the prevalence of eating disorders has been stable. Obesity was strongly associated with eating disorders both in 1991 and 2004.

Conclusion:

Despite the strong association between obesity and eating disorders, the increase in obesity is not followed by an increase in eating disorders. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008
Novel Furo‐pyridine Derivatives via Sonogashira Reactions of Functionalized Pyridines
Authors: Lechel Tilman , Dash Jyotirmayee , Brüdgam Irene , Reißig Hans‐Ulrich
Published: June 2008

A series of 4‐pyridyl nonaflates was coupled with several terminal alkynes to efficiently provide new 4‐alkynyl‐substituted 3‐alkoxypyridine derivatives. Apt conditions were developed for their conversion into furo[2,3‐c]pyridines. Sonogashira reactions of 4‐alkoxy‐substituted 3‐pyridyl nonaflates allowed an access to regioisomeric furo[3,2‐c]pyridines. For both types of alkynyl‐substituted alkoxypyridinesan alternative method for cyclization employing iodine monochloride furnished iodinated furo[2,3‐c]‐ or furo[3,2‐c]pyridines, which can undergo a second palladium‐catalyzed step. Iodination of 4‐hydroxypyridine derivative 24 with iodine afforded a pentasubstituted pyridine which after Sonogashira reaction immediately undergoes a cyclization to furo‐pyridine 25. Thus, three different types of furo‐pyridines can be prepared starting from one precursor. Several compounds prepared are fluorescent and show strong Stokes shifts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Is it a short‐memory, long‐memory, or permanently Granger‐causation influence?
Authors: Chen Wen‐Den
Published: June 2008

Exploring the Granger‐causation relationship is an important and interesting topic in the field of econometrics. In the traditional model we usually apply the short‐memory style to exhibit the relationship, but in practice there could be other different influence patterns. Besides the short‐memory relationship, Chen (2006) demonstrates a long‐memory relationship, in which a useful approach is provided for estimation where the time series are not necessarily fractionally co‐integrated. In that paper two different relationships (short‐memory and long‐memory relationship) are regarded whereby the influence flow is decayed by geometric, or cutting off, or harmonic sequences. However, it limits the model to the stationary relationship. This paper extends the influence flow to a non‐stationary relationship where the limitation is on −0.5 ≤ d ≤ 1.0 and it can be used to detect whether the influence decays off (−0.5 ≤ d < 0.5) or is permanent (0.5 ≤ d ≤ 1.0). Copyright © 2008 John Wiley & Sons, Ltd.
Pore Size Distribution and Water Uptake in Hydrocarbon and Perfluorinated Proton‐Exchange Membranes as Studied by NMR Cryoporometry
Authors: von Kraemer S. , Sagidullin A. I. , Lindbergh G. , Furó I. , Persson E. , Jannasch P.
Published: June 2008

Sulfonated polysulfone (sPSU) membranes were analysed by nuclear magnetic resonance (NMR) cryoporometry, conventional gravimetric water uptake measurements as well as by differential scanning calorimetry (DSC). NMR cryoporometry is based on the relation between the pore size and the melting point depression of the pore‐filling liquid, i.e. water in fuel cell membranes; thus providing a relation between the amount of molten water and the temperature shift, i.e. the pore size, in hydrated membranes. An sPSU membrane with high ion‐exchange capacity (IEC 1.45 mequiv. g–1) possessed a significant amount of large pores after hydrothermal pre‐treatment at 80 °C, which was related to its high hydrophilicity and low resistance towards swelling. An sPSU membrane with low IEC (0.95 mequiv. g–1) showed a significant fraction of small pores (r ∼ 1 nm) after hydrothermal pre‐treatment at 80 °C, implying a controlled water uptake of the membrane. NMR cryoporometry was also carried out on Nafion membranes, the results were found to be in agreement with the water uptake measurements and revealed a pore size distribution peak at r ∼ 1 nm. The NMR cryoporometry, gravimetric water uptake and DSC results are also discussed in terms of the state of the water and methodological differences.
Evaluation of automated brain MR image segmentation and volumetry methods
Authors: Klauschen Frederick , Goldman Aaron , Barra Vincent , Meyer‐Lindenberg Andreas , Lundervold Arvid
Published: June 2008

We compare three widely used brain volumetry methods available in the software packages FSL, SPM5, and FreeSurfer and evaluate their performance using simulated and real MR brain data sets. We analyze the accuracy of gray and white matter volume measurements and their robustness against changes of image quality using the BrainWeb MRI database. These images are based on “gold‐standard” reference brain templates. This allows us to assess between‐ (same data set, different method) and also within‐segmenter (same method, variation of image quality) comparability, for both of which we find pronounced variations in segmentation results for gray and white matter volumes. The calculated volumes deviate up to >10% from the reference values for gray and white matter depending on method and image quality. Sensitivity is best for SPM5, volumetric accuracy for gray and white matter was similar in SPM5 and FSL and better than in FreeSurfer. FSL showed the highest stability for white (<5%), FreeSurfer (6.2%) for gray matter for constant image quality BrainWeb data. Between‐segmenter comparisons show discrepancies of up to >20% for the simulated data and 24% on average for the real data sets, whereas within‐method performance analysis uncovered volume differences of up to >15%. Since the discrepancies between results reach the same order of magnitude as volume changes observed in disease, these effects limit the usability of the segmentation methods for following volume changes in individual patients over time and should be taken into account during the planning and analysis of brain volume studies. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Optimal cultivation rules in multi‐crop irrigation areas
Authors: Haddad O. Bozorg , Moradi‐Jalal M. , Mirmomeni M. , Kholghi M. Kh. , Mariño M. A.
Published: June 2008

A linear programming model is developed for annual cultivation rules of multi‐crop irrigation areas in a reservoir–irrigation system. The objective is to maximize the annual benefit of the system by assigning annual irrigation areas as well as monthly irrigation schedules over the planning horizon. The annual irrigation areas are considered to be a linear function of both total volume of storage at the end of the last operating year and the average inflow rate of the current year. The methodology is applied to a previously analyzed problem, without considering operational rules. Results are compared with those of a linearized modeling of the problem and the advantages of the proposed approach are discussed. Furthermore, results indicate that although there is a 40% decrease in the value of the objective function when using cultivation rules, the model is nonetheless a helpful tool for planners and/or stakeholders to decide at the beginning of each year how much and which type of product should be cultivated. This has been verified by applying the extracted rules with a generated five‐year inflow time series. Results show the robustness of the rules facing the uncertainty of model parameters. Copyright © 2008 John Wiley & Sons, Ltd.
Raman scattering and X‐ray diffraction on YBiTi2O7 prepared at low temperature
Authors: Garbout A. , Rubbens A. , Vannier R. N. , Bouattour S. , Kolsi A. W.
Published: June 2008

The conditions of preparation of a pure YBiTi2O7 phase by sol–gel were optimised. A single phase was obtained at temperature as low as 800 °C when triethanolamine/diethanolamine was used as additional ligands. The expected composition was confirmed by energy dispersive spectroscopy (EDS) and X‐ray diffraction (XRD). YBiTi2O7 exhibits the pyrochlore structure with a unit‐cell parameter of 10.2117(5) Å. This structure was confirmed by Raman spectroscopy, which revealed a shift of the main Eg mode towards lower wavenumbers when bismuth is introduced in the structure. Broad bands were observed for all the recorded spectra, which characterise rather a disorder due to bismuth III cations in the structure than an effect of particle size. This study confirmed the possibility to lower the temperature of preparation of pyrochlores containing bismuth, which could be of interest as photocatalyst for the decomposition of organic and toxic materials. Copyright © 2008 John Wiley & Sons, Ltd.
An efficient use of the WATERGATE W5 sequence for observing a ligand binding with a protein receptor
Authors: Furihata Kazuo , Shimotakahara Sakurako , Tashiro Mitsuru
Published: June 2008

An efficient pulse sequence for observing a ligand binding with a receptor has been developed by incorporating the WATERGATE W5 sequence. In the conventional water ligand observed via gradient spectroscopy (WaterLOGSY) techniques, the water resonance is selectively excited using,e.g. the double‐pulsed field gradient spin–echo (DPFGSE) sequence at the initial portion of pulse sequence. In the current version, the modified WATERGATE W5 sequence is incorporated at the initial portion of the pulse sequence, and the resonance at the water frequency can be selectively reserved by the modified WATERGATE W5 sequence. The efficiency of ligand‐observed NMR screening techniques has been demonstrated using the human serum albumin (HSA)–tryptophan complex. Copyright © 2008 John Wiley & Sons, Ltd.
A communication‐efficient framework for outlier‐free data reporting in data‐gathering sensor networks
Authors: Jayashree L. S. , Arumugam S. , Meenakshi A. R.
Published: June 2008

In this paper, we address the problem of reducing the communication cost and hence the energy costs incurred in data‐gathering applications of a sensor network. Environmental data depicts a huge amount of correlation in both the spatial and temporal domains. We exploit these temporal–spatial correlations to address the aforementioned problem. More specifically, we propose a framework that partitions the physical sensor network topology into a number of feature regions. Each sensor node builds a data model that represents the underlying structure of the data. A representative node in each feature region communicates only the model coefficients to the sink, which then uses them to answer queries. The temporal and spatial similarity has special meaning in outlier cleaning too. We use a modifiedz‐score technique to precisely label the outliers and use the spatial similarity to confirm whether the outliers are due to a true change in the phenomenon under study or due to faulty sensor nodes. Copyright © 2008 John Wiley & Sons, Ltd.