bluuebunny/crossref_metadata_2025 huggingface dataset:
Tailored Porous Silicon Microparticles: Fabrication and Properties
Authors: Chiappini Ciro , Tasciotti Ennio , Fakhoury Jean R. , Fine Daniel , Pullan Lee , Wang Young‐Chung , Fu Lianfeng , Liu Xuewu , Ferrari Mauro
Published: February 2010

The use of mesoporous silicon particles for drug delivery has been widely explored thanks to their biodegradability and biocompatibility. The ability to tailor the physicochemical properties of porous silicon at the micro‐ and nanoscale confers versatility to this material. A method for the fabrication of highly reproducible, monodisperse, mesoporous silicon particles with controlled physical characteristics through electrochemical etching of patterned silicon trenches is presented. The particle size is tailored in the micrometer range and pore size in the nanometer range, the shape from tubular to discoidal to hemispherical, and the porosity from 46 to over 80 %. In addition, the properties of the porous matrix are correlated with the loading of model nanoparticles (quantum dots) and their three‐dimensional arrangement within the matrix is observed by transmission electron microscopy tomography. The methods developed in this study provide effective means to fabricate mesoporous silicon particles according to the principles of rational design for therapeutic vectors and to characterize the distribution of nanoparticles within the porous matrix.
Post‐translational regulation of Crmp in developing and regenerating chick spinal cord
Authors: Gögel Stefanie , Lange Sigrun , Leung Kit‐Yi , Greene Nicholas D.E. , Ferretti Patrizia
Published: February 2010

It is becoming apparent that regulation at the protein level plays crucial roles in developmental and pathological processes. Therefore, we performed a proteomics screen to identify proteins that are differently expressed or modified at stages of development permissive (E11) and nonpermissive for regeneration (E15) of the chick spinal cord. Proteins regulated either developmentally or in response to spinal‐cord injury included collapsin‐response‐mediator proteins (Crmps), known to modulate microtubule dynamic and axonal growth. No significant changes in Crmp transcripts following injury were observed, indicating regulation mainly at the protein level. Analysis of Crmp‐2 protein and its phosphorylated forms, pS522 and pT514, showed that Crmp‐2 is developmentally regulated and also expressed in neural progenitors in vivo and in neurospheres. Its cellular localization changed both with development and following spinal‐cord injury. In addition, although overall levels of Crmp‐2 expression were not affected by injury, abundance of certain phosphorylated forms was altered. pT514 Crmp‐2 appeared to be associated with dividing neural progenitors and was greatly reduced at nonpermissive stages for regeneration, whereas it did not seem affected by injury. In contrast, phosphorylation of Crmp‐2 at S522 was upregulated early after injury in regenerating spinal cords and the ratio between phosphorylated to total Crmp‐2 increased, as indicated by 2D Western blots. Altogether, this study shows highly dynamic regulation of Crmp‐2 forms during development and identifies post‐translational changes in Crmp‐2 as putative contributors to the maintenance of spinal‐cord regenerative ability, possibly via a transient stabilization of the neuronal cytoskeleton. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 456–471, 2010
A unique expression pattern of Tbx10 in the hindbrain as revealed by Tbx10LacZ allele
Authors: Xue Xiao Dong , Kimura Wataru , Wang Bo , Hikosaka Keisuke , Itakura Tatsuo , Uezato Tadayoshi , Matsuda Masashi , Koseki Haruhiko , Miura Naoyuki
Published: February 2010

To study the expression/function of Tbx10, a T‐box gene, Tbx10LacZ/+ mice were established by replacing the T‐box coding region with a LacZ gene. X‐gal staining showed that LacZ+ cells were localized to two‐cell populations in rhombomere 4 and rhombomere 6. No significant differences in the locations of LacZ+ cells were found between Tbx10LacZ/+ and Tbx10LacZ/LacZ mice, and the Tbx10LacZ/LacZ mice were viable and fertile. We found that the LacZ+ cells are present in both embryonic and adult mice. Histological studies suggest that the rhombomere 4‐derived LacZ+ cells are a subpopulation of the ventral interneurons in the pons. genesis, 48:295–302, 2010. © 2010 Wiley‐Liss, Inc.
A Bipyridine‐Based “Naked‐Eye” Fluorimetric Cu2+ Chemosensor
Authors: Reynal Anna , Etxebarria Juan , Nieto Natalia , Serres Sílvia , Palomares Emilio , Vidal‐Ferran Anton
Published: February 2010

A series of six 2,2′‐bipyridine‐3,3′‐diols with different substituents have been synthesized and characterized. The designed ligands show fluorescence in the visible part of the spectra, but only the luminescence of the less sterically hindered molecules is quenched in the presence of Cu2+ ions. Selectivity and sensitivity of the chemosensors have been tested by absorption and luminescence spectroscopy in aqueous solutions, with a dynamic working range of 0.7–30 μM and a limit of detection of 0.04 ppm (mg L–1).
Capillary modified with covalently attached coating for enhanced CE separation of biopolymers
Authors: He Yuan , Wei Yinmao , Zheng Xiaohui , Zheng Jianbin
Published: February 2010

δ‐Gluconolactone was covalently coupled with aminopropyl‐derivatized capillary, creating hydrophilic brushes on the inner wall of the capillary. The hydrophilic coating provided suppression of EOF and minimized protein adsorption, resulting in the separation of basic proteins and DNA with efficiencies up to 450 000 plates/m. The intra‐ and inter‐day repeatabilities of the coating referring to the migration times of the four tested proteins were satisfactory with RSD of no more than 1.1 and 1.8% (n=5), respectively. Two hundred consecutive runs were performed with negligible change in migration times and efficiency.
CE coupled to MALDI with novel covalently coated capillaries
Authors: Bachmann Stefan , Vallant Rainer , Bakry Rania , Huck Christian W. , Corradini Danilo , Bonn Günther K.
Published: February 2010

CE offers the advantage of flexibility and method development options. It excels in the area of separation of ions, chiral, polar and biological compounds (especially proteins and peptides). Masking the active sites on the inner surface of a bare fused silica capillary wall is often necessary for CE separations of basic compounds, proteins and peptides. The use of capillary surface coating is one of the approaches to prevent the adsorption phenomena and improve the repeatability of migration times and peak areas of these analytes. In this study, new capillary coatings consisting of (i) derivatized polystyrene nanoparticles and (ii) derivatized fullerenes were investigated for the analysis of peptides and protein digest by CE. The coated capillaries showed excellent run‐to‐run and batch‐to‐batch reproducibility (RSD of migration time ≤0.5% for run‐to‐run and ≤9.5% for batch‐to‐batch experiments). Furthermore, the capillaries offer high stability from pH 2.0 to 10.0. The actual potential of the coated capillaries was tested by combining CE with MALDI‐MS for analysing complex samples, such as peptides, whereas the overall performance of the CE‐MALDI‐MS system was investigated by analysing a five‐protein digest mixture. Subsequently, the peak list (peptide mass fingerprint) generated from the mass spectra of each fraction was entered into the Swiss‐Prot database in order to search for matching tryptic fragments using the MASCOT software. The sequence coverage of analysed proteins was between 36 and 68%. The established technology benefits from the synergism of high separation efficiency and the structure selective identification via MS.
Differential effects of semantic processing on memory encoding
Authors: Fliessbach Klaus , Buerger Corinna , Trautner Peter , Elger Christian E. , Weber Bernd
Published: February 2010

Deeper semantic processing of words leads to enhanced memory encoding (depth of processing effect). The left inferior prefrontal cortex (LIPC) and the left hippocampus are known to be involved in this effect. We tested the hypothesis that different semantic encoding processes contribute qualitatively differently to memory encoding. In a memory experiment using functional magnetic resonance imaging, we compared three different encoding tasks: a nonsemantic alphabetical, an animacy decision, and a size comparison tasks. Recognition memory was tested subsequently. We hypothesized that the size comparison task would activate brain areas involved in the processing of object features and that this would be associated with successful memory encoding. Results showed that the size comparison task led to significantly better memory encoding than the two other tasks. As with the animacy decision task, it led to stronger activation of the LIPC and left hippocampus than the nonsemantic task. Both regions also had stronger activations for later remembered than for nonremembered words. The size comparison task additionally led to stronger activation in the left anterior fusiform gyrus, which was also associated with successful memory encoding. We conclude that different types of semantic processing affect memory encoding based on distinguishable brain processes. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Fronto‐cingulate effective connectivity in obsessive compulsive disorder: A study with fMRI and dynamic causal modeling
Authors: Schlösser Ralf G.M. , Wagner Gerd , Schachtzabel Claudia , Peikert Gregor , Koch Kathrin , Reichenbach Juergen R. , Sauer Heinrich
Published: February 2010

Evidence suggests that obsessive compulsive disorder (OCD) is associated with an overactive error control system. A key role in error detection and control has been ascribed to the fronto‐cingulate system. However, the exact functional interplay between the single components of this network in OCD is largely unknown. Therefore, the present study combined a univariate data analysis and effective connectivity analysis using dynamic causal modeling (DCM) to examine error control in 21 patients with OCD and 21 matched healthy controls. All subjects performed an adapted version of the Stroop color‐word task while undergoing fMRI scans. Enhanced activation in the fronto‐cingulate system could be detected in OCD patients during the incongruent task condition. Additionally, task‐related modulation of effective connectivity from the dorsal ACC to left DLPFC was significantly stronger in OCD patients. These findings are consistent with an overactive error control system in OCD subserving suppression of prepotent responses during decision‐making. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Decreased neuronal activity in reward circuitry of pathological gamblers during processing of personal relevant stimuli
Authors: de Greck Moritz , Enzi Björn , Prösch Ulrike , Gantman Ana , Tempelmann Claus , Northoff Georg
Published: February 2010

Pathological gamblers impress by an increasing preoccupation with gambling, which leads to the neglect of stimuli, interests, and behaviors that were once of high personal relevance. Neurobiologically dysfunctions in reward circuitry underlay pathological gambling. To explore the association of both findings, we investigated 16 unmedicated pathological gamblers using an fMRI paradigm that included two different tasks: the evaluation of personal relevance and a reward task that served as a functional localizer. Pathological gamblers revealed diminished deactivation during monetary loss events in some of our core reward regions, the left nucleus accumbens and the left putamen. Moreover, while pathological gamblers viewed stimuli of high personal relevance, we found decreased neuronal activity in all of our core reward regions, including the bilateral nucleus accumbens and the left ventral putamen cortex as compared to healthy controls. We demonstrated for the first time altered neuronal activity in reward circuitry during personal relevance in pathological gamblers. Our findings may provide new insights into the neurobiological basis of pathological gamblers' preoccupation by gambling. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Population‐based breast (female) and cervix cancer rates in the Gambia: Evidence of ethnicity‐related variations
Authors: Sighoko Dominique , Bah Ebrima , Haukka Jari , McCormack Valerie A. , Aka Elizabeth Patu , Bourgeois Denis , Autier Philippe , Byrnes Graham , Curado Maria Paula , Hainaut Pierre
Published: February 2010

Since 1987, the Gambia National Cancer Registry has provided nationwide cancer registration for the Gambia. We used data from 1998 to 2006 to assess age‐standardized incidence rates (ASRs) of 2 common cancers in women, breast and cervix. With an ASR of 15.42 (95% CI [14.18–16.66]) for cervix and 5.86 (95% CI [5.12–6.59]) for breast per 105 person‐years, these cancers ranked first and third, respectively, among Gambian women (the second most common being liver, ASR 14.90). Incidence of both cancers, breast and cervix, increased rapidly at young ages to reach a peak at ages 40–44 years. Significant differences were observed in relation to ethnicity. Using the Mandinka (42% of the population) as a reference, breast cancer incidence rates were 2.16‐fold higher (95% CI [1.33–3.52]) in Jola (10% of the population), specially at early‐onset ages (before 40 years). For cervix cancer, highest rates were observed in Fula (18% of the population; risk ratio (RR): 1.84 (95% CI [1.44–2.36])). In contrast, a significantly lower risk was observed in the Serrahuleh (9% of the population; RR: 0.54 (95% CI [0.31–0.96]). This study revealed a preponderance of early‐onset breast cancer among Gambian women similar to that seen in African women in more developed countries but also demonstrates large ethnic variations. It points to the need for further studies on cancer determinants to improve prevention, early detection and therapeutic management of these diseases in a low‐resource setting in West Africa.
Deregulation of the cell cycle by breast tumor kinase (Brk)
Authors: Chan Edward , Nimnual Anjaruwee S.
Published: February 2010

Brk is a cytoplasmic nonreceptor tyrosine kinase that is overexpressed in breast tumors but undetectable in normal or benign mammary tissues. Brk promotes proliferation of human mammary epithelial cells and tumor growth in a mouse model, but the role of Brk in cell cycle regulation is not known. In this study, we describe the mechanism of Brk‐induced deregulation of the cell cycle. We provide evidence that Brk antagonizes the transcriptional activity of the transcription factor FoxO family of proteins by inhibiting its nuclear localization. As a result, the cell cycle inhibitor p27, a FoxO target gene, is down‐regulated. This event is accompanied by G1/S cell cycle progression of quiescent cells. As p27 is a key regulator of the G1/S cell cycle checkpoint, these data suggest that perturbation of p27 expression induced by Brk causes S phase entrance. Deregulation of the cell cycle is a key event in neoplasia, and thus, the mechanism presented here likely contributes to breast cancer development.
miR‐34c is downregulated in prostate cancer and exerts tumor suppressive functions
Authors: Hagman Zandra , Larne Olivia , Edsjö Anders , Bjartell Anders , Ehrnström Roy A. , Ulmert David , Lilja Hans , Ceder Yvonne
Published: February 2010

MicroRNAs (miRNAs) are small noncoding RNAs that post‐transcriptionally regulate gene expression. There have been several reports of miRNA deregulation in prostate cancer (PCa) and the biological evidence for an involvement of miRNAs in prostate tumorigenesis is increasing. In this study, we show that miR‐34c is downregulated in PCa (p = 0.0005) by performing qRT‐PCR on 49 TURPs from PCa patients compared to 25 from patients with benign prostatic hyperplasia. The miR‐34c expression was found to inversely correlate to aggressiveness of the tumor, WHO grade, PSA levels and occurrence of metastases. Furthermore, a Kaplan–Meier analysis of patient survival based on miR‐34c expression levels divided into low (< 50th percentile) and high (> 50th percentile) expression, significantly divides the patients into high risk and low risk patients (p = 0.0003, log‐rank test). The phenotypic effects of miR‐34c deregulation were studied in prostate cell lines, where ectopic expression of miR‐34c decreased cell growth, due to both a decrease in cellular proliferation rate and an increase in apoptosis. In concordance to this, miR‐34c was found to negatively regulate the oncogenes E2F3 and BCL‐2, which stimulates proliferation and suppress apoptosis in PCa cells, respectively. Reversely, we could also show that blocking miR‐34c in vitro increases cell growth. Further, ectopic expression of miR‐34c was found to suppress migration and invasion. Our findings provide new insight into the role of miR‐34c in the prostate, exhibiting tumor suppressing effects on proliferation, apoptosis and invasiveness.
Characterization of a stretch‐activated potassium channel in chondrocytes
Authors: Mobasheri Ali , Lewis Rebecca , Maxwell Judith E.J. , Hill Claire , Womack Matthew , Barrett‐Jolley Richard
Published: February 2010

Chondrocytes possess the capacity to transduce load‐induced mechanical stimuli into electrochemical signals. The aim of this study was to functionally characterize an ion channel activated in response to membrane stretch in isolated primary equine chondrocytes. We used patch‐clamp electrophysiology to functionally characterize this channel and immunohistochemistry to examine its distribution in articular cartilage. In cell‐attached patch experiments, the application of negative pressures to the patch pipette (in the range of 20–200 mmHg) activated ion channel currents in six of seven patches. The mean activated current was 45.9 ± 1.1 pA (n = 4) at a membrane potential of 33 mV (cell surface area approximately 240 µm2). The mean slope conductance of the principal single channels resolved within the total stretch‐activated current was 118 ± 19 pS (n = 6), and reversed near the theoretical potassium equilibrium potential, EK+, suggesting it was a high‐conductance potassium channel. Activation of these high‐conductance potassium channels was inhibited by extracellular TEA (Kd approx. 900 µM) and iberiotoxin (Kd approx. 40 nM). This suggests that the current was largely carried by BK‐like potassium (MaxiK) channels. To further characterize these BK‐like channels, we used inside‐out patches of chondrocyte membrane: we found these channels to be activated by elevation in bath calcium concentration. Immunohistochemical staining of equine cartilage samples with polyclonal antibodies to the α1‐ and β1‐subunits of the BK channel revealed positive immunoreactivity for both subunits in superficial zone chondrocytes. These experiments support the hypothesis that functional BK channels are present in chondrocytes and may be involved in mechanotransduction and chemotransduction. J. Cell. Physiol. 223: 511–518, 2010. © 2010 Wiley‐Liss, Inc.
An analysis of precipitation data from the Antarctic base Faraday/Vernadsky
Authors: Kirchgäßner Amélie
Published: February 2010

A recent study on cloud observations reports an increase in total cloud cover at Faraday/Vernadsky since 1960 in the annual and wintertime data. The aim of this present study is to investigate whether this increase in total cloud cover has influenced the precipitation in this region. For this purpose, precipitation observations at the Antarctic base Faraday/Vernadsky between 1960 and 1999 were analysed. A positive trend, significant at the 5% level, was found in the number of precipitation events recorded during winter, showing an increase of 13 events per decade. The annual number of precipitation days has increased by 5.7 per decade during the period of investigation, with highest increase rates being observed in winter and autumn. The characteristics of these findings confirm that results previously published though trends presented here are ∼50% smaller due to a more thorough data quality control of the observational data. These results indicate that an increase in total cloud cover at Faraday/Vernadsky observed since 1960 in the annual and wintertime data is reflected in higher numbers of precipitation events and days. Analyses of the precipitation type found an increase in the proportion of events of non‐frozen precipitation, which is significant (1% level) on an annual basis as well as in spring and autumn (both significant at 5% level). This is a clear manifestation of the year round temperature increase observed over the Antarctic Peninsula. The increase in non‐frozen precipitation will have reduced the albedo in the region and will thus have contributed to the temperature‐albedo feedback. To refreeze rain that is draining through glaciers energy is extracted from the surrounding ice, thereby physically corroding the ice. This will have contributed to the observed retreat of glaciers around the Antarctic Peninsula. As non‐frozen precipitation falling on frozen ground cannot be stored but instead runs off, less water will be available for the ecosystem. Copyright © 2010 Royal Meteorological Society
Augmentation of surgical angiogenesis in vascularized bone allotransplants with host‐derived a/v bundle implantation, fibroblast growth factor‐2, and vascular endothelial growth factor administration
Authors: Larsen Mikko , Willems Wouter F. , Pelzer Michael , Friedrich Patricia F. , Yaszemski Michael J. , Bishop Allen T.
Published: February 2010

We have previously shown experimental transplantation of living allogeneic bone to be feasible without long‐term immunosuppression by development of a recipient‐derived neoangiogenic circulation within bone. In this study, we examine the role of angiogenic cytokine delivery with biodegradable microspheres to enhance this process. Microsurgical femoral allotransplantation was performed from Dark Agouti to Piebald Virol Glaxo rats. Poly(D,L‐lactide‐co‐glycolide) microspheres loaded with buffer, basic fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF), or both, were inserted intramedullarly along with a recipient‐derived arteriovenous (a/v) bundle. FK‐506 was administered daily for 14 days, then discontinued. At 28 days, bone blood flow was measured using hydrogen washout. Microangiography, histologic, and histomorphometric analyses were performed. Capillary density was greater in the FGF+VEGF group (35.1%) than control (13.9%) (p < 0.05), and a linear trend was found from control, FGF, VEGF, to FGF+VEGF (p < 0.005). Bone formation rates were greater with VEGF (p < 0.01) and FGF+VEGF (p < 0.05). VEGF or FGF alone increased blood flow more than when combined. Histology rejection grading was low in all grafts. Local administration of vascular and fibroblast growth factors augments angiogenesis, bone formation, and bone blood flow from implanted blood vessels of donor origin in vascularized bone allografts after removal of immunosuppression. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1015–1021, 2010
Wear, delamination, and fatigue resistance of melt‐annealed highly crosslinked UHMWPE cruciate‐retaining knee inserts under activities of daily living
Authors: Popoola Oludele O. , Yao Jian Q. , Johnson Todd S. , Blanchard Cheryl R.
Published: February 2010

The wear, delamination, and fatigue resistance of artificially aged gamma irradiation‐sterilized conventional polyethylene (CPE) and gas‐plasma‐sterilized melt‐annealed highly crosslinked polyethylene tibial inserts (HXPE) were compared. Six CPE and 12 HXPE (six irradiated at 58 kGy and six at 72 kGy) left knee inserts were wear tested for 5.5 million cycles (Mc) under loads and motions that mimic activities of daily living, such as walking, chair rise, stair ascent, and deep squatting. Another six HXPE (72 kGy) and six CPE inserts were also tested under conditions that could produce severe delamination for 8 Mc. Ten other knees (five 72 kGy HXPE and five CPE) were subjected to posterior edge loading fatigue testing for 5 Mc. The HXPE inserts had an average wear rate reduction of about 80% relative to their CPE counterparts during all activities. All of the CPE inserts delaminated and fractured during high cycle deep squat (152° flexion) motions, while all the HXPE remained intact. None of the HXPE inserts delaminated after 8 Mc, while all of the CPE inserts developed delamination damage within 1.5–5.8 Mc of delamination testing. All CPE inserts developed subsurface cracks and delamination within 2.8 Mc during posterior edge loading fatigue studies, while none of the HXPE inserts showed cracking or delamination after 5 Mc. These results show that aged HXPE has higher wear and fatigue resistance than aged CPE, and offers potential long‐term advantages for young active patients with sustained activities of daily living. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1120–1126, 2010
Luminescent determination of flavonoids in orange juices by LC with post‐column derivatization with aluminum and terbium
Authors: Andreu‐Navarro Alvaro , Fernández‐Romero Juan Manuel , Gómez‐Hens Agustina
Published: February 2010

A new post‐column derivatization system is described and applied to the determination of flavonoids in citric beverages after their separation by LC using a monolithic column. The derivatization involves the formation of the chelates of the analytes with aluminum (III) and terbium (III) in the presence of the surfactant SDS and the measurement of the terbium sensitized luminescence at λex 360 and λem 545 nm. Naringin, hesperidin, quercetin, naringenin, and kaempferol have been chosen as analyte models. The large Stokes shift and the relatively long wavelength emission of terbium(III) can minimize interferences from background sample matrix, which usually emit at shorter wavelengths. Calibration graphs were constructed in the intervals 6.0–1700 ng/mL naringin, 9.8–1700 ng/mL hesperidin, 2.1–2000 ng/mL quercetin, 5.2–1500 ng/mL naringenin and 2.5–2000 ng/mL kaempferol, with regression coefficients higher than 0.9935 in all instances. The precision of the method, expressed as RSD%, was established at two concentration levels, with values of 1.3 and 4.7%, which corresponded to the minimal and maximal error zones of the calibration graphs. The practical usefulness of the method is demonstrated by the analysis of orange juices, which were diluted and directly injected into the chromatographic system, obtaining recoveries between 86.9 and 108.2%.
Perioral skin biopsy to study skeletal muscle protein expression
Authors: Santoro Lucio , Nolano Maria , Faraso Stefania , Fiorillo Chiara , Vitiello Carmen , Provitera Vincenzo , Aurino Stefania , Nigro Vincenzo
Published: February 2010

Clinical trials for muscular dystrophy molecular treatment require multiple sampling of skeletal muscle to monitor protein rescue. This practice is invasive and could raise ethical problems. A less invasive tool to obtain sequential muscle sampling is necessary. Using indirect immunofluorescence, we evaluated muscle protein expression in myofiber bundles included in 2–2.5‐mm punch skin biopsies from the perioral region from 6 healthy subjects and 6 patients with genetically defined forms of muscular dystrophy. Large intradermal bundles of orbicularis oris muscle were constantly present in skin biopsies. They showed a typical muscular antigenic pattern in controls and the expected protein defect in muscular dystrophy patients. These results demonstrate the feasibility of muscular protein expression analysis using skin biopsy. We propose this minimally invasive technique to follow‐up the response to genetic or conventional therapies in muscular dystrophies and to confirm the diagnosis in some special clinical conditions. Muscle Nerve 41: 392–398, 2010
Effective electrical conductivity of nanocomposites. Influence of image forces on contact conductivity of metal‐filled polymer nanocomposites
Authors: Novikov V.V. , Friedrich Chr. , Nezhevenko K.A.
Published: February 2010

The generalized effective conductivity of a heterogeneous medium with chaotic structure is defined based on the ideas of the renormalization group transformation method and the theory of fractals. The fractal sets obtained from rectangular lattices have been used to construct the structure of a nanocomposite with random distribution of components (phases). A model for the calculation of effective electrical conductivity of filled polymer nanocomposites is developed. It is based on conductivity between two filler particles separated by matrix polymer as an elementary conductivity event and the application of an iterative averaging method. The comparison of the calculation and experimental data of different filled polymer systems shows good agreement. PACS: 72.80 Tm; 72.60+ g; and 84.32 Ff. POLYM. COMPOS., 31:1541–1553, 2010. © 2009 Society of Plastics Engineers
Characterization of polyaniline/Ag nanocomposites using H2O2 and ultrasound radiation for enhancing rate
Authors: Li Zhihua , Wang Yanwei
Published: February 2010

Polyaniline/Ag nanocomposites have been synthesized via in situ chemical oxidation polymerization of aniline in silver salt by sonochemical method using H2O2 as an external medium. H2O2 was used to reduce AgNO3 to Ag nanoparticles as well as to polymerize aniline to polyaniline in the same pot. The ultrasound radiation as an energy source was applied to facilitate the reaction by reducing the reaction time. Reduction of the silver salt in aqueous aniline leads to the formation of silver nanoparticles which in turn catalyze oxidation of aniline to polyaniline. The research on the structures and properties of the composites showed the individual or aggregated silver nanoparticles are dispersed in the matrix of polyaniline. The composites possess a higher degradation temperature than polyaniline alone, and their electrical conductivity are raised morethan 200 times. The cyclic voltammetry and impedance spectroscopy results showed that the polyaniline/Ag film exhibits considerably higher electroactivity compared with polyaniline film without Ag particles. POLYM. COMPOS., 31:1662–1668, 2010. © 2009 Society of Plastics Engineers
Kinetics of the phase selective localization of silica in rubber blends
Authors: Le Hai Hong , Ilisch Sybill , Heidenreich Daniel , Wutzler André , Radusch Hans‐Joachim
Published: February 2010

The Fourier transformed infrared (FTIR) spectroscopy on the rubber‐filler gel has been used as a tool for the quantitative characterization of the phase selective silica localization in styrene butadiene rubber (SBR)/natural rubber (NR) blends. The so‐called rubber‐layer L was introduced to describe the selective wetting behavior of the rubber phases to the filler. SBR/NR blends filled with silica were the focus of the experimental investigation. NR shows a higher wetting rate than SBR. Silane addition does not affect the wetting of NR but slowdowns the wetting of SBR. With increasing chamber temperature the value of the rubber‐layer L of all mixtures increases owing to the different thermal activated rubber‐filler bonding processes. Using the wetting concept the kinetics of silica localization in the phases of heterogeneous rubber blends was characterized. Because of the higher wetting rate of the NR component, in the first stage of mixing of NR/SBR blends more silica is found in the NR phase than in the SBR phase. In the next stage, silica is transferred from the NR phase to the SBR phase until the loosely bonded components of NR rubber‐layer are fully replaced by SBR molecules. POLYM. COMPOS., 31:1701–1711, 2010. © 2010 Society of Plastics Engineers.
Improvement of mechanical properties of structural thermoplastic composites using a reactive (low molecular weight) matrix component
Authors: Aurilia M. , Sorrentino L. , Iannace S.
Published: February 2010

An innovative manufacturing process for continuous fiber composites with the polymeric matrix made up of polypropylene and epoxy resin, as a model reactive low molecular weight component, was developed; variable process parameters give rise to different morphologies of matrix components surrounding the woven fabric reinforcement. Furthermore, the combination of both thermoplastic and thermosetting polymers permitted intimate fibers impregnation, typical of thermosetting matrix composites, with short process cycle time, which usually occurs in manufacturing process of thermoplastic matrix composites. Polypropylene (PP) films, glass fibers fabric, and epoxy resin film were used to produce flat composite through film‐stacking technique. The preparation process focused on control of both epoxy resin cure process and polypropylene melting. The process was able to induce the two matrix components to form either a planar (sandwich‐like) structure or a three‐dimensional (3D) network by means of controlling the process parameters such as pressure and heating rate. The strong enhancement of the mechanical properties (Young's modulus and tensile strength of the composites with the 3D structure were almost twice as high of those of the composites with sandwich‐like matrix structure) was due to the different microstructures produced by the interplanar flow of the thermoplastic polymer. POLYM. COMPOS., 31:1762–1769, 2010. © 2010 Society of Plastics Engineers.
Morphological and dielectric properties of barium chloride‐filled poly(vinylidene fluoride) films
Authors: Ozkazanc Ersel , Guney H. Yuksel , Guner Selahaddin , Abaci Ufuk
Published: February 2010

Morphological characteristics of poly(vinylidene fluoride) (PVDF) films, filled with mass fractions (w ≤ 20%) of Barium Chloride (BaCl2), were investigated by X‐ray diffraction (XRD), Fourier transform infrared (FTIR) absorption spectra and differential scanning calorimetry (DSC) measurements. The dielectric properties of films were measured from 250 Hz to 1 MHz range between 100 and 400 K as a function of frequency and temperature. Spectroscopic data revealed that the filled and unfilled films include α‐, β‐, and γ‐crystalline phases. By a 20% filling, 73% increase was obtained in the total degree of crystallinity. Since the BaCl2 formed fluorine bridges over the chain segments on the crystal lamellar surface, the γ‐crystalline phase decreased, whereas the total degree of crystallinity increased. Dielectric measurements showed that maximum of the dielectric loss factor belonging to β‐relaxation transition decreased linearly with filling level. The filling process did not have any effect on the real dielectric constant till α‐relaxation transition region. However, in the α‐relaxation transition region, it was determined that the real dielectric constant increased linearly with filling level. POLYM. COMPOS., 31:1782–1789, 2010. © 2010 Society of Plastics Engineers.
Comprehensive proteome profiling of the Fe(III)‐reducing myxobacterium Anaeromyxobacter dehalogenans 2CP‐C during growth with fumarate and ferric citrate
Authors: Chao Tzu‐Chiao , Kalinowski Jörn , Nyalwidhe Julius , Hansmeier Nicole
Published: February 2010

Anaeromyxobacter dehalogenans is a microaerophilic member of the delta‐proteobacteria which is able to utilize a wide range of electron acceptors, including halogenated phenols, U(VI), Fe(III), nitrate, nitrite, oxygen and fumarate. To date, the knowledge regarding general metabolic activities of this ecologically relevant bacterium is limited. Here, we present a first systematic 2‐D reference map of the soluble A. dehalogenans proteome in order to provide a sound basis for further proteomic studies as well as to gain first global insights into the metabolic activities of this bacterium. Using a combination of 2‐DE and MALDI‐TOF‐MS, a total of 720 proteins spots were identified, representing 559 unique protein species. Using the proteome data, altogether 50 metabolic pathways were found to be expressed during growth with fumarate as primary electron acceptor. An analysis of the pathways revealed an extensive display of enzymes involved in the catabolism and anabolism of a variety of amino acids, including the unexpected fermentation of lysine to butyrate. Moreover, using the reference gel as basis, a semi‐quantitative analysis of protein expression changes of A. dehalogenans during growth with ferric citrate as electron acceptor was conducted. The adaptation to Fe(III) reducing conditions involved the expression changes of a total of 239 proteins. The results suggest that the adaptation to Fe(III) reductive conditions involves an increase in metabolic flux through the tricarboxylic acid cycle, which is fueled by an increased catabolism of amino acids.
New Horizons: why a more collaborative approach is needed
Authors: Walton Ian
Published: February 2010

Most of us welcome the new direction of travel for mental health advocated by the recently published cross‐government action programme New Horizons,1 the 2008 Lord Darzi report High Quality Care for All2 plus the 2007 personalisation agenda Putting People First.3. Copyright © 2010 Wiley Interface Ltd
Treatment of vector equations in deep‐atmosphere, semi‐Lagrangian models. I: Momentum equation
Authors: Staniforth A. , White A. A. , Wood N.
Published: February 2010

Application of the semi‐Lagrangian method to the vector momentum equation in orthogonal curvilinear systems is considered, with emphasis on spherical and spheroidal coordinates for deep‐atmosphere models (in which the shallow‐atmosphere approximation is not made). In spherical coordinates, a certain rotation matrix allows vector components at semi‐Lagrangian departure points to be expressed in the required component forms at the corresponding arrival points. This rotation matrix also allows the unit vector triad at the arrival point to be expressed in terms of the unit vector triad at the departure point. The resulting formalisation of the momentum equation applies to timesteps of arbitrary length, and in the limit of infinitesimal timestep it delivers the familiar Eulerian components. Extension of the rotation matrix technique to more general orthogonal curvilinear systems is remarkably straightforward, thus demonstrating the versatility of the semi‐Lagrangian method. Explicit forms are given for systems having longitude as one coordinate and general orthogonal coordinates in the meridional plane, and in particular these forms are applicable to both confocal oblate spheroidal and similar oblate spheroidal systems. A specific factorisation of the rotation matrix in the spherical polar case involves three matrices, one of which represents rotation of the unit vector triad along a great circle arc; the non‐Euclidean, shallow‐atmosphere approximation of the total rotation matrix results when the great circle rotation matrix is replaced by the identity matrix (but the other two matrices involved in the factorisation are kept intact). This shallow‐atmosphere rotation matrix agrees with that used by ECMWF and Météo‐France. © Crown Copyright 2010. Published by John Wiley & Sons, Ltd.
Pedro: a publish/subscribe server using Prolog technology
Authors: Robinson Peter J. , Clark Keith L.
Published: February 2010

Pedro is a TCP/IP publish/subscribe server implemented in C that uses Prolog technology for testing subscriptions against notifications. It provides both content‐ and address‐based routing of messages between processes. An inter‐process message M is a string representation of a Pedro term (usually but not necessarily a variable free term). A subscription is essentially a message template T paired with a Pedro query that is used to restrict the allowed values for variables in T. Pedro automatically forwards any notification it receives to all processes that have a current subscription that covers the notification. A Pedro connected process can optionally register a name with Pedro giving the process a unique Pedro handle. Pedro handles can be used to send peer‐to‐peer messages between processes. In this paper we illustrate the use of Pedro and describe its implementation. Copyright © 2010 John Wiley & Sons, Ltd.
Chemical inhibition of CaaX protease activity disrupts yeast Ras localization
Authors: Manandhar Surya P. , Hildebrandt Emily R. , Jacobsen William H. , Santangelo George M. , Schmidt Walter K.
Published: February 2010

Proteins possessing a C‐terminal CaaX motif, such as the Ras GTPases, undergo extensive post‐translational modification that includes attachment of an isoprenoid lipid, proteolytic processing and carboxylmethylation. Inhibition of the enzymes involved in these processes is considered a cancer‐therapeutic strategy. We previously identified nine in vitro inhibitors of the yeast CaaX protease Rce1p in a chemical library screen (Manandhar et al., 2007). Here, we demonstrate that these agents disrupt the normal plasma membrane distribution of yeast GFP–Ras reporters in a manner that pharmacologically phenocopies effects observed upon genetic loss of CaaX protease function. Consistent with Rce1p being the in vivo target of the inhibitors, we observe that compound‐induced delocalization is suppressed by increasing the gene dosage of RCE1. Moreover, we observe that Rce1p biochemical activity associated with inhibitor‐treated cells is inversely correlated with compound dose. Genetic loss of CaaX proteolysis results in mistargeting of GFP–Ras2p to subcellular foci that are positive for the endoplasmic reticulum marker Sec63p. Pharmacological inhibition of CaaX protease activity also delocalizes GFP–Ras2p to foci, but these foci are not as strongly positive for Sec63p. Lastly, we demonstrate that heterologously expressed human Rce1p can mediate proper targeting of yeast Ras and that its activity can also be perturbed by some of the above inhibitors. Together, these results indicate that disrupting the proteolytic modification of Ras GTPases impacts their in vivo trafficking. Copyright © 2010 John Wiley & Sons, Ltd.
Serum MIP‐1 α level: a biomarker for the follow‐up of lentiviral therapy in mucopolysaccharidosis IIIB mice
Authors: Di Natale Paola , Di Domenico Carmela , Di Napoli Daniele
Published: February 2010

Mucopolysaccharidosis (MPS) IIIB is an inherited lysosomal storage disorder caused by deficiency of alpha‐N‐acetylglucosaminidase (NAGLU). The disease is characterized by mild somatic features and severe neurological involvement, with high mortality rates. Although some therapeutic approaches have been applied to the murine model of the disease, no effective therapy is available. Moreover, assessing therapeutic efficacy is challenged by the lack of markers to for progression and severity. In this study, we examined the effect of brain‐directed lentiviral (LV) gene therapy on serum levels of macrophage inflammatory protein 1 alpha (MIP‐1α) and brain‐derived neurotrophic factor (BDNF) proteins in the murine model of MPS IIIB to identify novel serum biomarkers. The cytokine MIP‐1α was elevated in MPS IIIB mouse serum, and following gene therapy, it was reduced to normal levels. For neurotrophin BDNF, the difference in serum levels between MPS IIIB and normal mice was not statistically significant; after LV gene therapy, an increase in protein was found in treated mice, although the values were not statistically significant. Our studies suggest MIP‐1α as the first serum biomarker that could be used to monitor disease progression and treatment for MPS IIIB disease.
Bounded and unbounded Fredholm modules for quantum projective spaces
Authors: D'Andrea Francesco , Landi Giovanni
Published: February 2010

We construct explicit generators of the K-theory and K-homology of the coordinate algebras of ‘functions’ on the quantum projective spaces. We also sketch a construction of unbounded Fredholm modules, that is to say Diraclike operators and spectral triples of any positive real dimension.
Kinematics and source zone properties of the 2004 Sumatra‐Andaman earthquake and tsunami: Nonlinear joint inversion of tide gauge, satellite altimetry, and GPS data
Authors: Lorito S. , Piatanesi A. , Cannelli V. , Romano F. , Melini D.
Published: February 2010

We (re)analyzed the source of the 26 December 2004 Sumatra‐Andaman earthquake and tsunami through a nonlinear joint inversion of an inhomogeneous data set made up of tide gauges, satellite altimetry, and far‐field GPS recordings. The purpose is twofold: (1) the retrieval of the main kinematics rupture parameters (slip, rake, and rupture velocity) and (2) the inference of the rigidity of the source zone. We independently estimate the slip from tsunami data and the seismic moment from geodetic data to derive the rigidity. Our results confirm that the source of the 2004 Sumatra‐Andaman earthquake has a complex geometry, constituted by three main slip patches, with slip peaking at ∼30 m in the southern part of the source. The rake direction rotates counterclockwise at the northern part of the source, according to the direction of convergence along the trench. The rupture velocity is higher in the deeper than in the shallower part of the source, consistent with the expected increase of rigidity with depth. It is also lower in the northern part, consistent with known variations of the incoming plate properties and shear velocity. Our model features a rigidity (20–30 GPa) that is lower than the preliminary reference Earth model (PREM) average for the seismogenic volume. The source rigidity is one of the factors controlling the tsunami genesis: for a given seismic moment, the lower the rigidity, the higher the induced seafloor displacement. The general consistence between our source model and previous studies supports the effectiveness of our approach to the joint inversion of geodetic and tsunami data for the rigidity estimation.
Hallmarks of maghemitization in low‐temperature remanence cycling of partially oxidized magnetite nanoparticles
Authors: Özdemir Özden , Dunlop David J.
Published: February 2010

In environmental, soil, and sediment magnetism, it is important to be able to estimate the degree of oxidation of magnetite grains. We report a new method for finding the oxidation parameter z semiquantitatively from cooling‐warming cycles of room temperature remanences. We measured magnetization M continuously for stoichiometric and partially oxidized magnetites with average grain sizes of 37 and 220 nm during zero‐field cycling of 2.5 T saturation isothermal remanent magnetization (SIRM) from 300 K to 20 K and back to 300 K. Oxidized magnetites were obtained by heating stoichiometric magnetite in air at 100°C, 150°C, and 200°C. In other experiments, SIRM was given at 10 K, and M was monitored during zero‐field warming to 300 K. In the oxidized magnetites, SIRM at first increases in cooling from 300 K and then decreases in approaching the Verwey transition. The hump‐like form is even more pronounced in the warming curves above TV. For maghemite, the fully oxidized end member, we found reversible cooling‐warming curves with no Verwey transition. In partially oxidized grains, consisting of a maghemite surface layer and a largely unoxidized core, a Verwey transition is resolvable up to high degrees of oxidation. Hallmarks of maghemitization include (1) a smeared‐out Verwey transition shifted to lower temperatures when warming 20 K SIRM, (2) a shifted and broadened transition region in both cooling and warming of 300 K SIRM, and (3) humped cooling and warming curves of 300 K SIRM between 300 K and TV. Property 3 has excellent diagnostic value. It results from the combination of a slowly increasing M of maghemite and the rapid and nonlinear decrease in M of magnetite during cooling and is seen even for the slight initial oxidation of the reduced 37 nm magnetite. Certain properties, such as the change in M in warming from 20 K to TV and the change in initial and final M values in a complete cooling‐warming cycle, are roughly proportional to the oxidation parameter z. However, the proportionality factors also depend on grain size d, which would have to be known independently in order to estimate z.
Frank M. Richter Receives 2009 Harry H. Hess Medal
Authors: Rowley David B. , Richter Frank M.
Published: February 2010

Frank M. Richter was awarded the 2009 Harry H. Hess Medal at the AGU Fall Meeting Honors Ceremony, held on 16 December 2009 in San Francisco, Calif. The medal is for “outstanding achievements in research in the constitution and evolution of Earth and other planets.”