bluuebunny/crossref_metadata_2025 huggingface dataset:
Littlewood–Paley characterizations for Hardy spaces on spaces of homogeneous type
Authors: Han Yongsheng , Müller Detlef , Yang Dachun
Published: September 2006

Let (𝒳, d,μ) be a space of homogeneous type in the sense of Coifman and Weiss. Assuming that μ satisfies certain estimates from below and there exists a suitable Calderón reproducing formula in L 2(𝒳), the authors establish a Lusin‐area characterization for the atomic Hardy spaces H p at(𝒳) of Coifman and Weiss for p ∈ (p 0, 1], where p 0 = n /(n + ε 1) depends on the “dimension” n of 𝒳 and the “regularity” ε 1 of the Calderón reproducing formula. Using this characterization, the authors further obtain a Littlewood–Paley g *λ ‐function characterization for Hp (𝒳) when λ > n + 2n /p and the boundedness of Calderón–Zygmund operators on Hp (𝒳). The results apply, for instance, to Ahlfors n ‐regular metric measure spaces, Lie groups of polynomial volume growth and boundaries of some unbounded model domains of polynomial type in ℂN . (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy Transfer from Locally Excited π* to Charge Transfer Ground States in a Silylene–π Hetero‐Junction Polymer
Authors: Kwak Giseop , Takagi Akiko , Fujiki Michiya
Published: September 2006

Summary: The silylene–π conjugating polymer, poly(di‐n‐hexylsilylenephenylene‐ethynylenephenylene) (1) adopted a fairly flexible coil‐like conformation due to the bent structure of silylene moiety and showed a unique photoexcited energy transfer behavior. The UV‐vis absorption and steady‐state/time‐resolved photoluminescence studies revealed the occurrence of an intramolecular photoexcited energy transfer (IET) between locally excited π* to charge transfer ground states as well as an intramolecular charge transfer (ICT).

The silylene–π conjugating polymer, poly(di‐n‐hexylsilylenephenylene‐ethynylenephenylene) showing a unique photoexcited energy transfer behavior.

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The silylene–π conjugating polymer, poly(di‐n‐hexylsilylenephenylene‐ethynylenephenylene) showing a unique photoexcited energy transfer behavior.
Porphyrinated Nanofibers via Copolymerization and Electrospinning
Authors: Wan Ling‐Shu , Wu Jian , Xu Zhi‐Kang
Published: September 2006

Summary: The first example of the synthesis of acrylonitrile copolymers with porphyrin pendants and the subsequent electrospinning of the resultant copolymers into nanofibers is presented in this communication. Vinyl porphyrin monomers have been synthesized and copolymerized with acrylonitrile through solution polymerization. FT‐IR, NMR, UV‐vis, and fluorescence spectroscopy are used to characterize the copolymers. Preliminary quantum chemical calculations have also been carried out to reveal the activity of the vinyl porphyrin monomers. Nanofibers with a diameter of around 330 nm are prepared by electrospinning the copolymer solutions. Their morphology and porphyrination are clearly observed by field‐emission scanning electron microscopy and fluorescence microscopy. It is speculated that this type of nanofiber may be a latent support of porphyrins for various purposes such as catalysis, molecular imprinting, sensors, and light/energy conversion.

The formation of luminescent nanofibers from porphyrinated polymers.

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The formation of luminescent nanofibers from porphyrinated polymers.
Isoconversional Kinetic Analysis of Thermally Stimulated Processes in Polymers
Authors: Vyazovkin Sergey , Sbirrazzuoli Nicolas
Published: September 2006

Summary:Isoconversional kinetic analysis involves evaluating a dependence of the effective activation energy on conversion or temperature and using this dependence for making kinetic predictions and for exploring the mechanisms of thermally stimulated processes. The paper discusses major results obtained by the authors in the area of the isoconversional analysis of polymer kinetics over the past decade. It provides a brief introduction to isoconversional methods and surveys the impact made by isoconversional analysis in several application areas that include kinetic predictions, thermal degradation, crosslinking (curing), glass transition, and glass and melt crystallization. It is concluded that isoconversional analysis has been used broadly and fruitfully because it presents a fortunate compromise between the single‐step Arrhenius kinetic treatments and the prevalent occurrence of processes whose kinetics are multi‐step and/or non‐Arrhenius.

An isoconversional method applies the Arrhenius equation to a narrow temperature region, ΔTrelated to a given extent of conversion.

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An isoconversional method applies the Arrhenius equation to a narrow temperature region, ΔTrelated to a given extent of conversion.
Matrix‐free methods for laser desorption/ionization mass spectrometry
Authors: Peterson Dominic S.
Published: September 2006

Matrix assisted laser desorption/ionization (MALDI) is a soft ionization mass spectrometric method that has become a preeminent technique in the analysis of a wide variety of compounds including polymers and proteins. The main drawback of MALDI is that it is difficult to analyze low molecular weight compounds (<1,000 m/z) because the matrix that allows MALDI to work interferes in this mass range. In recent years there has been considerable interest in developing laser desorption/ionization (LDI) techniques for the analysis of small molecules. This review examines the approaches to matrix‐free LDI mass spectrometry including desorption/ionization on silicon (DIOS), sol‐gels, and carbon‐based microstructures. For the purposes of this review matrix‐free methods are defined as those that do not require matrix to be mixed with the analyte and therefore does not require co‐crystallization. The review will also examine mechanisms of ionization and applications of matrix‐free LDI‐MS. © 2006 Wiley Periodicals, Inc., Mass Spec Rev 26:19–34, 2007
Application of capillary electrophoresis mass spectrometry to the characterization of bacterial lipopolysaccharides
Authors: Li Jianjun , Richards James C.
Published: September 2006

Capillary electrophoresis (CE) is a high‐resolution technique for the separation of complex biological mixtures and has been widely applied to biological analyses. The coupling of capillary electrophoresis with mass spectrometry (MS) provides a powerful approach for rapid identification of target analytes present at trace levels in biological matrices, and for structural characterization of complex biomolecules. Here we review the analytical potential of combined capillary electrophoresis electrospray mass spectrometry (CE‐MS) for the analysis of bacterial lipopolysaccharides (LPS). This hyphened methodology facilitates the determination of closely related LPS glycoform and isoform families by exploiting differences in their unique molecular conformations and ionic charge distributions by electrophoretic separation. On‐line CE‐MS also provides an additional avenue to improve detection limits, which has been successfully applied to directly probe oligosaccharide LPS glycoform populations of bacteria isolated from infected animal models without the need for further passage. © 2006 Wiley Periodicals, Inc., Mass Spec Rev 26:35–50, 2007
Nephropathy and defective spermatogenesis in mice transgenic for a single isoform of the Wilms' tumour suppressor protein, WT1−KTS, together with one disrupted Wt1 Allele
Authors: Lahiri Diya , Dutton James R. , Duarte Antonio , Moorwood Kim , Graham Christopher F. , Ward Andrew
Published: September 2006

The Wilms' tumour suppressor protein, WT1, is a zinc finger protein essential for the development of several organs, including the kidney and gonads. In each of these tissues WT1 is required at multiple stages of development and its persistent expression in podocytes and Sertoli cells suggests WT1 may also have a role in the maintenance of kidney and testis function throughout adult life. Naturally occurring isoforms of WT1 are generated by alternative mRNA splicing. An altered ratio of the splice isoforms WT1−KTS and WT1 + KTS appears to be sufficient to account for the developmental abnormalities (pseudohermaphroditism and nephropathy) characteristic of Frasier syndrome. We show that mice with a transgene encoding WT1−KTS do not differ from their wild‐type littermates unless they are also heterozygous for a null mutation at the endogenous Wt1 locus. Animals with both genetic modifications develop proteinuria, together with multiple glomerular cysts, and male infertility. These pathologic changes may be explained as a consequence of altering the WT1 isoform ratio in tissues that express WT1 during adulthood. The results suggest WT1 misexpression could contribute to human glomerulocystic kidney disease. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.
Synergistic induction of apoptosis in primary rat decidual cells by INF‐γ and TNF
Authors: Almeida A. , Correia‐da‐Silva G. , Cepa M. , Bell S.C. , Teixeira N.A.
Published: September 2006

In the rat, in response to blastocyst implantation, stromal cells of the endometrium proliferate and differentiate into decidual cells, forming the decidua. After reaching its maximum development, the decidua undergoes regression. This phenomenon appears to be due to an active process involving apoptosis. As there is sparse knowledge concerning the mechanisms of induction of decidual cell death, the potential role of cytokines present in the uterine environment during pregnancy, such as tumor necrosis factor (TNF) and interferon‐γ (INF‐γ) was explored in primary cultures of rat decidual cells. The effects of these factors upon cellular viability, nuclear morphologic alterations, expression, and enzymatic activities of the effector caspases‐3/7 were evaluated. The results obtained demonstrated that in contrast to TNF, which did not induce any alteration, INF‐γ and in association with TNF caused a decrease in cell viability and an increase in the appearance of apoptotic bodies in a time‐dependent manner that was augmented in the co‐presence of TNF. An increase in caspase‐3/7 activities after 12 hr of TNF/INF‐γ treatment was also observed. These findings suggest that INF‐γ expressed in the uterine environment may play an important role in regulating apoptosis through potential synergistic mechanisms with TNF and thereby modulate decidual stability and regression during pregnancy. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.
High iNOS mRNA and protein levels during early third trimester suggest a role for NO in prelabor cervical ripening in the bovine
Authors: Aalberts Marian , van Dissel‐Emiliani Federica M.F. , van Tol Helena T.A. , Taverne Marcel A.M. , Breeveld‐Dwarkasing Vidya N.A.
Published: September 2006

Nitric oxide (NO) plays a key role in the processes leading to cervical softening prior to labor. Inducible nitric oxide synthase (iNOS) contributes most to the increased production of NO during labor, as demonstrated in the rat cervix, or at term pregnancy in women. Changes in expression of iNOS during late gestation have not yet been studied longitudinally in any species, because repeatedly taking biopsies could not be performed. iNOS mRNA (n = 6) and protein expression (n = 3) in serial cervical biopsies of pregnant pluriparous cows taken around days 225, 250, and 275 of pregnancy and within 1.5 hr after calving (d225, d250, d275 and parturition biopsies, respectively) were measured using quantitative RT‐PCR and Western blotting. iNOS mRNA expression decreased from the d225 biopsy onwards, differences being significant between the d250 and d275 (P < 0.05) and between the d275 and parturition biopsies (P < 0.05). iNOS protein expression decreased from d225 to d250 onwards. Immunohistochemical analysis of biopsies showed, besides positive staining in endothelium and epithelium, which remained unchanged at different time points, that iNOS expressing cells in the connective tissue cells of early biopsies were predominantly spindle shaped (mostly smooth muscle cells and some fibroblasts). In the parturition biopsies, iNOS reactivity was mainly found in mononuclear leucocytes. These results lead us to suggest that iNOS from spindle shaped cells is involved in prepartum cervical ripening, while iNOS in mononuclear inflammatory cells may be important for local tissue repair mechanisms during postpartum cervical involution. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.
Structural abnormalities in spermatids together with reduced sperm counts and motility underlie the reproductive defect in HIP1−/− mice
Authors: Khatchadourian Karine , Smith Charles E. , Metzler Martina , Gregory Mary , Hayden Michael R. , Cyr Daniel G. , Hermo Louis
Published: September 2006

Huntingtin interacting protein 1 (HIP1) is an endocytic adaptor protein with clathrin assembly activity that binds to cytoplasmic proteins, such as F‐actin, tubulin, and huntingtin (htt). To gain insight into diverse functions of HIP1, we characterized the male reproductive defect of HIP1−/− mice from 7 to 30 weeks of age. High levels of HIP1 protein were expressed in the testis of wild‐type mice as seen by Western blots and as a reaction over Sertoli cells and elongating spermatids as visualized by immunocytochemistry. Accordingly, major structural abnormalities were evident in HIP1−/− mice with vacuolation of seminiferous tubules caused by an apparent loss of postmeiotic spermatids and a significant reduction in mean profile area. Remaining spermatids revealed deformations of their heads, flagella, and/or acrosomes. In some Sertoli cells, ectoplasmic specializations (ES) were absent or altered in appearance accounting for the presence of spherical germ cells in the epididymal lumen. Quantitative analyses of sperm counts from the cauda epididymidis demonstrated a significant decrease in HIP1−/− mice compared to wild‐type littermates. In addition, computer‐assisted sperm analyses indicated that velocities, amplitude of lateral head displacements (ALH), and numbers and percentages of sperm in the motile, rapid, and progressive categories were all significantly reduced in HIP1−/− mice, while the numbers and percentages of sperm in the static category were greatly increased. Taken together, these various abnormalities corroborate reduced fertility levels in HIP1−/− mice and suggest a role for HIP1 in stabilizing actin and microtubules, which are important cytoskeletal elements enabling normal spermatid and Sertoli cell morphology and function. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.
Double trouble (McArdle's disease and myasthenia gravis): How can exercise help?
Authors: Lucia Alejandro , Maté‐Muñoz José L. , Pérez Margarita , Foster Carl , Gutiérrez‐Rivas Eduardo , Arenas Joaquín
Published: September 2006

We report a 29‐year‐old patient with McArdle's disease and myasthenia gravis. She had been debilitated with McArdle's disease since childhood (with marked rhabdomyolysis) and was obese. Myasthenia gravis was diagnosed at 24 years of age. After 3 months of aerobic exercise training, her exercise capacity increased significantly and she regained the ability to live independently. We conclude that even patients with profound neuromuscular diseases may benefit from carefully prescribed exercise training. Muscle Nerve, 2006
Celiac disease and antibodies associated with celiac disease in patients with inflammatory myopathy
Authors: Selva‐O'Callaghan Albert , Casellas Francesc , de Torres Ines , Palou Eduard , Grau‐Junyent Josep M. , Vilardell‐Tarrés Miquel
Published: September 2006

Celiac disease is usually associated with autoimmune disorders and has occasionally been reported in patients with inflammatory myopathies. Our aim was to determine the presence of celiac disease and antibodies associated with celiac disease in patients with inflammatory myopathies and to investigate their relationship. Serum antigliadin, anti–tissue transglutaminase, and antiendomysial antibodies were determined in 51 patients with inflammatory myopathies. HLA‐DQ2 and ‐DQ8 alleles were studied to assess their complementary diagnostic value. Jejunal biopsy was performed in patients with moderate to high levels of antigliadin antibodies. Patients with jejunal histology consistent with celiac disease initiated a gluten‐free diet. Seventeen patients (31%) were positive for antigliadin antibodies, which were significantly more frequent in patients with inclusion‐body myositis than dermatomyositis (P < 0.001). Positive status to HLA‐DQ2 and/or ‐DQ8 did not differ between antigliadin‐positive (75% and 12.5%) or ‐negative (60% and 15%) patients. Three of five jejunal biopsies were diagnostic for celiac disease with histological normalization after a gluten‐free diet. Thus, celiac disease is more prevalent in patients with inflammatory myopathies than in the general population. Positive status to HLA‐DQ2 allele, which is known to be more frequent in patients with inflammatory myopathies, could explain the high prevalence of antigliadin antibodies in this population. The diagnostic value of HLA‐DQ2 or ‐DQ8 haplotypes to detect celiac disease in patients with inflammatory myopathy is limited. Muscle Nerve, 2006
Predictability of disease progression in amyotrophic lateral sclerosis
Authors: Czaplinski Adam , Yen Albert A. , Simpson Ericka P. , Appel Stanley H.
Published: September 2006

The aim of this study was to determine the predictors of disease progression in a group of 832 patients with the diagnosis of definite or probable amyotrophic lateral sclerosis (ALS). Disease progression was defined as the time to 20‐point change in Appel ALS (AALS) score. The effects of individual prognostic factors on disease progression were assessed with the Kaplan–Meier life‐table method. In addition, the prognostic value of each factor was estimated using both univariate and multivariate Cox proportional hazard analyses. The median time to a 20‐point change in AALS score in our patient population was 9 months. Age, site of symptom onset, time between first symptom and first examination, total AALS score at first examination, and AALS preslope (rate of disease progression between first symptom and first examination) were significant and independent covariates of disease progression in our population. Identification of predictors of disease progression will facilitate better design of therapeutic trials, permitting the use of disease progression as a primary endpoint and improving baseline stratification of patient populations. Muscle Nerve, 2006
Variable presentation of nemaline myopathy: Novel mutation of alpha actin gene
Authors: Bouldin Anthony A. , Parisi Melissa A. , Laing Nigel , Patterson Kathleen , Gospe Sidney M.
Published: September 2006

Nemaline myopathy is a rare disorder of varying severity and genetic etiology. We present two cases, a father and son, with a novel missense mutation in the alpha actin gene. Both have a history of early motor impairment, with the son's course being considerably more severe. This pair illustrates the clinical variability of nemaline myopathy, highlighting the possible influence of environmental and epigenetic factors. Implications for the current classification system and prognosis are discussed. Muscle Nerve, 2006
Rituximab treatment in patients with IVIg‐dependent immune polyneuropathy: A prospective pilot trial
Authors: Gorson Kenneth C. , Natarajan Neela , Ropper Allan H. , Weinstein Robert
Published: September 2006

We studied the effect of rituximab in allowing a reduction in dose of intravenous immune globulin (IVIg) in six patients with IVIg‐dependent, relapsing immune polyneuropathy. Rituximab (375 mg/m2intravenously each week for 4 weeks) was administered in a prospective, open‐label design to two patients with chronic inflammatory demyelinating polyneuropathy (CIDP), two with multifocal motor neuropathy (MMN), one with neuropathy and anti–myelin‐associated glycoprotein (MAG) antibody neuropathy, and one with Sjögren syndrome (SS) ataxic neuropathy. The primary endpoint was a reduced cumulative IVIg dosage by at least 25% at 1 year after rituximab therapy compared to the previous year. Secondary endpoints included an improved summed strength score by at least 5 points on the Medical Research Council scale, an increased sensory score by at least 4 points, or an improved Rankin disability score by at least 1 grade. Total IVIg dosage decreased by greater than 25% in one patient with SS neuropathy and one with MMN; the dosage was unchanged in one with CIDP, slightly reduced in the patient with anti‐MAG neuropathy, and increased in one with CIDP and another with MMN. There was no improvement in secondary endpoints. No adverse events occurred. In this small prospective study, rituximab did not reduce IVIg requirements in the majority of patients with IVIg‐dependent, immune‐mediated polyneuropathies. Muscle Nerve, 2006
Analysis of liquefaction susceptibility of nearly saturated sands
Authors: Jafari‐Mehrabadi Ahmad , Abedinzadegan Abdi Majid , Popescu Radu
Published: September 2006

A new constitutive formulation for simulating the behaviour of nearly saturated sands under seismic loads is presented. The formulation is based on combining the Henry's law for dissolution of gas in water, the ideal or perfect gas law and the law of conservation of mass. The effects of transient air dissolution in water on the compressibility of partially saturated soils are also taken into account. The model was calibrated based on numerical simulations of isotropically consolidated cyclic triaxial tests conducted on partially saturated samples of Toyoura sand. A multi‐yield plasticity soil constitutive model implemented in the finite element code DYNAFLOW was used for these numerical simulations. It is shown that the formulation proposed here is able to reasonably predict the soil cyclic undrained behaviour at various degrees of saturation (95% and higher). Copyright © 2006 John Wiley & Sons, Ltd.
Distinct functions of neuronal synaptobrevin in developing and mature fly photoreceptors
Authors: Rister Jens , Heisenberg Martin
Published: September 2006

Neuronal synaptobrevin (n‐Syb, alias VAMP2), a synaptic vesicle membrane protein with a central role in neurotransmission, is specifically cleaved by the light chain of tetanus neurotoxin (TNT) that is known to reliably block neuroexocytosis. Here, we study fly photoreceptors transmitting continuous, graded signals to first order interneurons in the lamina, and report consequences of targeted expression of TNT in these cells using the UAS/GAL4 driver/effector system. Expressing the toxin throughout photoreceptor development causes developmental, electrophysiological, and behavioral defects. These can be differentiated by confining toxin expression to shorter developmental periods. Applying a method for controlled temporal and spatial TNT expression, we found that in the early pupa it impaired the development of the retina; in the midpupa, during synapse formation TNT caused a severe hypoplasia of the lamina that persisted into adulthood and left the photoreceptor‐interneuron synapses of the lamina without function. Finally, during adulthood TNT neither blocks synaptic transmission in photoreceptors nor depletes the cells of n‐Syb. Our study suggests a novel, cell type‐specific function of n‐Syb in synaptogenesis and it distinguishes between two synapse types: TNT resistant and TNT sensitive ones. These results need to be taken into account if TNT is used for neural circuit analysis. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Gβγ that interacts with adenylyl cyclase in opioid tolerance originates from a Gs protein
Authors: Wang Hoau‐Yan , Burns Lindsay H.
Published: September 2006

We previously demonstrated that chronic morphine induces a change in G protein coupling by the mu opioid receptor (MOR) from Gi/o to Gs, concurrent with the instatement of an interaction between Gβγ and adenylyl cyclase types II and IV. These two signaling changes confer excitatory effects on the cell in place of the typical inhibition by opioids and are associated with morphine tolerance and dependence. Both signaling changes and these behavioral manifestations of chronic morphine are attenuated by cotreatment with ultra‐low‐dose naloxone. In the present work, using striatum from chronic morphine‐treated rats, we isotyped the Gβ within Gs and Go heterotrimers that coupled to MOR and compared these to the Gβ isotype of the Gβγ that interacted with adenylyl cyclase II or IV after chronic morphine treatment. Isotyping results show that chronic morphine causes a Gs heterotrimer associated with MOR to release its Gβγ to interact with adenylyl cyclase. These data suggest that the switch to Gs coupling by MOR in response to chronic morphine, which is attenuated by ultra‐low‐dose opioid antagonist cotreatment, leads to a two‐pronged stimulation of adenylyl cyclase utilizing both Gα and Gβγ subunits of the Gs protein novel to this receptor. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Reduction in nerve growth factor availability leads to a conditioning lesion‐like effect in sympathetic neurons
Authors: Shoemaker S.E. , Sachs H. Hyatt , Vaccariello S.A. , Zigmond R.E.
Published: September 2006

Axotomized peripheral neurons are capable of regeneration, and the rate of regeneration can be enhanced by a conditioning lesion (i.e., a lesion prior to the lesion after which neurite outgrowth is measured). A possible signal that could trigger the conditioning lesion effect is the reduction in availability of a target‐derived factor resulting from the disconnection of a neuron from its target tissue. We tested this hypothesis with respect to nerve growth factor (NGF) and sympathetic neurons by administering an antiserum to NGF to adult mice for 7 days prior to explantation or dissociation of the superior cervical ganglion (SCG) and subsequently measuring neurite outgrowth. The antiserum treatment dramatically lowered the concentration of NGF in the SCG and increased the rate of neurite outgrowth in both explants and cell cultures. The increase in neurite outgrowth was similar in magnitude to that seen after a conditioning lesion. To determine if exogenous NGF could block the effect of a conditioning lesion, mice were injected with NGF or cytochrome C immediately prior to unilateral axotomy of the SCG, and for 7 days thereafter. A conditioning lesion effect of similar magnitude was seen in NGF‐treated and control animals. While NGF treatment increased NGF levels in the contralateral control ganglion, it did not significantly elevate levels in the axotomized ganglion. The results suggest that the decreased availability of NGF after axotomy is a sufficient stimulus to induce the conditioning lesion effect in sympathetic neurons. While NGF administration did not prevent the conditioning lesion effect, this may be due to the markedly decreased ability of sympathetic neurons to accumulate the growth factor after axotomy. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Tissue inhibitor of metalloproteinase‐2 (TIMP‐2) regulates neuromuscular junction development via a β1 integrin‐mediated mechanism
Authors: Lluri Gentian , Langlois Garret D. , McClellan Brian , Soloway Paul D. , Jaworski Diane M.
Published: September 2006

Extracellular matrix (ECM) molecules play critical roles in muscle function by participating in neuromuscular junction (NMJ) development and the establishment of stable, cytoskeleton‐associated adhesions required for muscle contraction. Matrix metalloproteinases (MMPs) are neutral endopeptidases that degrade all ECM components. While the role of MMPs and their inhibitors, the tissue inhibitor of metalloproteinases (TIMPs), has been investigated in many tissues, little is known about their role in muscle development and mature function. TIMP‐2 −/− mice display signs of muscle weakness. Here, we report that TIMP‐2 is expressed at the NMJ and its expression is greater in fast‐twitch (extensor digitorum longus, EDL) than slow‐twitch (soleus) muscle. EDL muscle mass is reduced in TIMP‐2−/− mice without a concomitant change in fiber diameter or number. The TIMP‐2−/− phenotype is not likely due to increased ECM proteolysis because net MMP activity is actually reduced in TIMP‐2−/− muscle. Most strikingly, TIMP‐2 colocalizes with β1 integrin at costameres in the wild‐type EDL and β1 integrin expression is significantly reduced in TIMP‐2−/− EDL. We propose that reduced β1 integrin in fast‐twitch muscle may be associated with destabilized ECM‐cytoskeletal interactions required for muscle contraction in TIMP‐2−/− muscle; thus, explaining the muscle weakness. Given that fast‐twitch fibers are lost in muscular dystrophies and age‐related sarcopenia, if TIMP‐2 regulates mechanotransduction in an MMP‐independent manner it opens new potential therapeutic avenues. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Development of composites with recycled PET matrix
Authors: Ronkay F. , Czigány T.
Published: September 2006

Injection molded composites with recycled poly(ethylene terephthalate) (PET) matrices, reinforced with glass and basalt fiber were prepared, containing 15, 30 and 45 wt % fiber. Fiber fracture and the interaction of various fibers and the matrix were analyzed in the micro‐droplet test during processing. It was established that the basalt fibers, which are much cheaper than glass fibers improve substantially the tensile and flexural moduli without causing a significant decrease in the tensile and impact strength values. It was shown that the approximate critical fiber length calculated from the maximum pull‐out fiber length from the fracture surfaces differs from that determined by micro‐droplet tests. Copyright © 2006 John Wiley & Sons, Ltd.
Wettability and spectroscopic characterization of silylated wood samples
Authors: Mohammed‐Ziegler Ildikó , Hórvölgyi Zoltán , Tóth András , Forsling Willis , Holmgren Allan
Published: September 2006

Surfaces of three European wood species (namely, English oak, Hungarian oak, and Scots pine) and two tropical wood species (namely, teak and cloves) were silylated with dichlorodimethylsilane (DDS), dichlorodiphenylsilane (DPS) and octadecyltrichlorosilane (OTS) in the first step, and with chlorotrimethylsilane (CTMS) as a monofunctional reagent in a second step. Attenuated total reflection‐Fourier transform infrared (ATR‐FT‐IR) and electron spectroscopy for chemical analysis (ESCA) measurements were performed in order to characterize the surface composition of the treated samples. The progress of surface modification was also monitored by contact angle measurements of different test liquids (water, formamide and diiodomethane). The water contact angles were found to be in the range of 80° to 145°. The most hydrophobic surface was obtained by two‐step silylation by OTS and CTMS (water contact angles were between 131° and 140°). Interestingly, the hydrophobicity of DDS‐treated samples showed a significant decrease after additional silylation by CTMS. The surface free energy values were evaluated in terms of the Lifshitz‐van der Waals/acid‐base theory. The results obtained by the surface analytical methods (i.e. FT‐IR and ESCA measurements) were compared with the contact angle data. These results suggest that in the case of DDS‐treated samples, CTMS molecules substitute partly the DDS molecules, thus only physisorption of the silylating agents is supposed at room temperature. Copyright © 2006 John Wiley & Sons, Ltd.
Advanced surface modification of ultra‐high molecular weight poly(ethylene) by helium plasma immersion ion implantation
Authors: Tóth A. , Mohai M. , Ujvári T. , Bertóti I.
Published: September 2006

Plasma immersion ion implantation is an emerging, versatile, relatively simple and cost‐effective surface modification technique, alternative to conventional ion implantation. With this method even irregularly shaped objects can be uniformly treated, enhancing thus their surface properties. Ultra‐high molecular weight polyethylene is a principal biomaterial currently used in total joint arthroplasty, the wear of which and in particular the wear debris induced osteolysis is the main cause of the premature failure of the hip joint prostheses.

In order to improve the wear resistance of ultra‐high molecular weight polyethylene, in this work it was surface treated by plasma immersion ion implantation in helium. Process parameters like acceleration voltage, fluence and fluence rate were varied systematically. X‐ray photoelectron spectroscopy was applied to monitor the surface chemical changes. Alterations induced in the surface mechanical and wear properties like hardness, reduced modulus and volume loss were determined by nanoindentation and multipass wear test measurements. The results demonstrate that the applied treatment can significantly modify the surface chemical and nanomechanical properties and increase the wear resistance of ultra‐high molecular weight polyethylene. Copyright © 2006 John Wiley & Sons, Ltd.
Flame retardancy of epoxy resin with phosphorus‐containing reactive amine and clay minerals
Authors: Toldy A. , Tóth N. , Anna P. , Keglevich Gy. , Kiss K. , Marosi Gy.
Published: September 2006

Flame retardant effect of newly synthesized phosphorus‐containing reactive amine, which can be used both as crosslinking agent in epoxy resins and as flame retardant, was explored. The effect of montmorillonite and sepiolite additives on thermal stability and flame retardancy was compared in the epoxy resin matrix. Copyright © 2006 John Wiley & Sons, Ltd.
Novel dually responsive hydrogel with rapid deswelling rate
Authors: Xiang Yuan‐Qing , Zhang Yan , Chen Da‐Jun
Published: September 2006

Hydrogels based on 2‐hydroxyethyl methacrylate (HEMA), methacrylic acid (MAA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) were prepared by free radical polymerization. The prepared hydrogels were characterized using Fourier transform infrared spectrometry. The states of water in the hydrogels were probed using differential scanning calorimetry and three types of water (free, freezing bound and non‐freezing bound) were detected, the contents of which were calculated. Compared with conventional poly(HEMA‐co‐MAA) hydrogels, the deswelling rate of the poly(HEMA‐co‐PEGMA‐co‐MAA) hydrogels is significantly improved, owing to the introduction of PEGMA. The deswelling process can be well described with a first‐order kinetics equation. Moreover, the swelling ratio of poly(HEMA‐co‐PEGMA‐co‐MAA) hydrogels exhibits a temperature dependence. Based on the analysis of the components of the hydrogels, a brushed core/shell structure is proposed for these, and confirmed by transmission electron microscopy observations. Copyright © 2006 Society of Chemical Industry
Quintessence from proteomics networks – the HUPO Brain Proteome Project Pilot Studies
Authors: Meyer Helmut E. , Hamacher Michael
Published: September 2006

No abstracts.
Kinetic modeling of controlled living microemulsion polymerizations that use reversible addition–fragmentation chain transfer
Authors: Hermanson Kevin D. , Liu Shiyong , Kaler Eric W.
Published: September 2006

Reversible addition–fragmentation chain transfer (RAFT) polymerization is a useful technique for the formation of polymers with controlled architectures and molecular weights. However, when used in the polymerization of microemulsions, RAFT agents are only able to control the polymer molecular weight only at high RAFT concentrations. Here, a kinetic model describing RAFT microemulsion polymerizations is derived that predicts the reaction rates, molecular weight polydispersities, and particle size. The model predicts that at low RAFT concentrations, the RAFT agent will be consumed early in the reaction and that this will result in uncontrolled polymerization in particles nucleated late in the reaction. The higher molecular weight polydispersity that is observed in RAFT microemulsion polymerizations is the result of this uncontrolled polymerization. The model also predicts a shift in the conversion at which the maximum reaction rate occurs and a decrease in the particle size with increasing RAFT concentration. Both of these trends are also consistent with those observed experimentally. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6055–6070, 2006
Synthesis and self‐assembly morphologies of amphiphilic multiblock copolymers [poly(ethylene oxide)‐b‐polystyrene]n via trithiocarbonate‐embedded PEO macro‐RAFT agent
Authors: Jia Zhongfan , Xu Xuewei , Fu Qiang , Huang Junlian
Published: September 2006

An amphiphilic multiblock copolymer [poly(ethylene oxide)‐b‐polystyrene]n [(PEO‐b‐PS)n] is synthesized by using trithiocarbonate‐embedded PEO as macro‐RAFT agent. PEO with four inserted trithiocarbonate (Mn = 9200 and Mw/Mn = 1.62) groups is prepared first by condensation of α, ω‐dihydroxyl poly(ethylene oxide) with S, S′‐Bis(α, α′‐dimethyl‐α″‐acetic acid)‐trithiocarbonate (BDATC) in the presence of pyridine, then a series of goal copolymers with different St units (varied from 25 to 218 per segment) are obtained by reversible addition‐fragmentation chain transfer (RAFT) polymerization. The synthesis process is monitored by size exclusion chromatography (SEC), 1H NMR and FT‐IR. The self‐assembled morphologies of the copolymers are strongly dependent of the length of PS block chains when the chain length of PEO is fixed, some new morphologies as large leaf‐like aggregates (LLAs), large octopus‐like aggregates (LOAs), and coarse‐grain like micelles (CGMs) are observed besides some familiar aggregates as large compound vesicles (LCVs), lamellae and rods, and the effect of water content on the morphologies is also discussed. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6071–6082, 2006
Synthesis of well‐defined macromonomers by the combination of atom transfer radical polymerization and a click reaction
Authors: Liu Qingchun , Chen Yongming
Published: September 2006

This article presents a new strategy for synthesizing a series of well‐defined macromonomers. Bromine‐terminated polystyrene and poly(t‐butyl acrylate) with predetermined molecular weights and narrow distributions were prepared through the atom transfer radical polymerization of styrene and t‐butyl acrylate initiated with ethyl 2‐bromoisobutyrate. Then, azido‐terminated polymers were obtained through the bromine substitution reaction with sodium azide. Catalyzed by CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine, the azido end group reacted with propargyl methacrylate via a 1,3‐dipolar cycloaddition reaction, and ω‐methacryloyl‐functionalized macromonomers were thus obtained. The end‐group transformation yields were rather high, as characterized by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectra and 1H NMR analysis. By this effective and facile approach, some novel macromonomers that otherwise are difficult to achieve, such as poly(ethylene oxide)‐block‐polystyrene, were easily prepared. Radical homopolymerizations of these macromonomers were performed, and a series of comb polymers were prepared. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6103–6113, 2006
Synthesis, photoluminescence, and electrochromic properties of wholly aromatic polyamides bearing naphthylamine chromophores
Authors: Liou Guey‐Sheng , Yen Hung‐Ju
Published: September 2006

A series of novel polyamides with pendent naphthylamine units having inherent viscosities of 0.15–1.02 dL/g were prepared via direct phosphorylation polycondensation from various diamines and a naphthylamine‐based aromatic dicarboxylic acid, 1‐[N,N‐di(4‐carboxyphenyl)amino]naphthalene. These amorphous polyamides were readily soluble in various organic solvents and could be cast into transparent and tough films. The aromatic polyamides had useful levels of thermal stability associated with high glass‐transition temperatures (268–355 °C), 10% weight loss temperatures in excess of 480 °C, and char yields at 800 °C in nitrogen higher than 60%. These polymers showed maximum ultraviolet–visible absorption at 350–358 nm and exhibited fluorescence emission maxima around 435–458 nm in N‐methyl‐2‐pyrrolidinone solutions with fluorescence quantum yields ranging from 0.4 to 15.0%. The hole‐transporting and electrochromic properties were examined with electrochemical and spectroelectrochemical methods. Cyclic voltammograms of the polyamide films cast onto an indium tin oxide coated glass substrate exhibited one oxidative redox couple around 1.08–1.16 V (oxidation onset potential) versus Ag/AgCl in an acetonitrile solution and revealed good stability of the electrochromic characteristics, with a color change from colorless to green at applied potentials ranging from 0 to 1.6 V. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6094–6102, 2006
3D crystal growth model for understanding the role of plasma pre‐treatment on CVD diamond crystal shape
Authors: Silva F. , Achard J. , Bonnin X. , Michau A. , Tallaire A. , Brinza O. , Gicquel A.
Published: September 2006

The progress that has been achieved over the past few years on the growth of thick and high purity homo‐epitaxial single crystal diamond by chemical vapour deposition (CVD) has opened a wide range of possible applications in areas such as optics or power electronics. Recently, high quality single crystals were produced at LIMHP with growth rates close to 20 µm/h using relatively high microwave power density, both in continuous and pulsed mode [1, 2]. However, these results are conditioned by the use of an in‐situ etching of the diamond substrate prior to growth using a H2/O2 plasma. This pre‐treatment results in better and smoother morphologies of the homoepitaxial diamond layer [3] compared to growth on an untreated substrate. Moreover, the initial quality of the diamond substrate was demonstrated to be critical for the final morphology of the CVD epitaxial film. Still, the impact of surface defects on the initial diamond substrate and the role of the pre‐treatment on the final morphology of the grown film remained partially unclear. Indeed, diamond homoepitaxial growth on untreated substrates leads to unexpected morphology and geometry of the crystal. To explain these observations, a 3D purely geometrical growth model has been developed, involving the growth rate of (100), (111), as well as (110) and (113) faces. The model provi‐ des a consistent explanation of the substrate pre‐treatment effect on the growth and morphology of the crystal. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Theoretical studies on 〈100〉 dislocations in single crystal CVD diamond
Authors: Fujita N. , Blumenau A. T. , Jones R. , Öberg S. , Briddon P. R.
Published: September 2006

Dislocations are common defects in both natural as well as in CVD‐grown diamond. Recent advances in the growth of high quality single crystal CVD diamond have led to an increased interest in the atomistic and electronic structure of 〈100〉 dislocations. These dislocations are observed as mixed‐type 45° and pure edge dislocations. Hence in this work we present ab initio modelling studies on these two types of dislocations. The 45° dislocation is found to be by far more stable than the pure edge and both dislocations lead to states in the electronic band gap. An alternative structure for the mixed‐type dislocation, which is not straight but kinked and consists of short edge and screw segments, was found slightly higher in energy than the straight structure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural defects in homoepitaxial diamond layers grown on off‐axis Ib HPHT substrates
Authors: Bauer T. , Schreck M. , Härtwig J. , Liu X. H. , Wong S. P. , Stritzker B.
Published: September 2006

In the present study homoepitaxial diamond films have been grown by microwave plasma chemical vapour deposition (MWPCVD) on (001)‐oriented Ib HPHT substrates with off‐axis angles of up to 11°. Freestanding films of several hundred microns thickness were produced by removal of the Ib substrate and of the polycrystalline rim. In high resolution X‐ray diffraction (HRXRD) rocking curve measurements the crystals showed a full width at half maximum (FWHM) between (2 × 10–3)°, which is close to the instrumental limit of our setup, and maximum values of (3 × 10–2)°. The structural quality is directly reflected in the strength of the birefringence observed in the optical microscope. While the high quality sample showed a weak birefringence with a couple of localized centres distributed over the whole sample surface, a tatami‐like pattern is measured for the sample with the broad rocking curve. Identical defect structures with perfect correspondence are observed in X‐ray topography images. Furthermore the X‐ray topographs allow to identify isolated dislocation lines. Both characterisation methods show that the defect lines are aligned along the off‐axis direction which allows conclusions on the mechanism of formation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nanocarbon field emission devices
Authors: Subramanian K. , Wong Y. M. , Kang W. P. , Davidson J. L. , Choi B. K. , Howell M.
Published: September 2006

We are fabricating and examining nanocarbon derived electron emission devices, specifically, nanodiamond lateral field emission diodes and gated carbon nanotube triodes. These novel microstructures provide interesting means of accomplishing electronics that are unaffected by temperature and radiation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
All optical read‐out radiation dosimeter using CVD synthetic diamond
Authors: Preciado‐Flores S. , Schreck M. , Meléndrez R. , Chernov V. , Pedroza‐Montero M. , Barboza‐Flores M.
Published: September 2006

In the present work, we evaluate the optically stimulated luminescence (OSL) dosimetric properties of two polycrystalline 10 μm thick films, undoped and 750 ppm nitrogen doped, grown on (100) silicon substrates exposed to beta radiation. The samples were optically stimulated to free and to induce radiative recombination of the trapped charges caused by radiation absorption. This all optical technique uses IR laser 830 nm light for stimulation and a PMT coupled to a BG‐39 (300–600 nm) filter for light intensity measurements. The OSL of both samples is very similar in output intensity and hyperbolic decay type. The OSL signal of non doped samples involves localized trapping states around the 373–653 K as compared to nitrogen doped sample which involves the charge detrapping of localized states in the 353–550 K range. The OSL signal in the first 0.16 s shows two linearity regions for 0–35 Gy and 35–100 Gy dose ranges. An obvious advantage of OSL over TL/TSC methods is that no heating is required, it may also open the possibility of using CVD diamond coupled to optical fibers for stimulation and read‐out light signals allowing in situ and real time dose measurements. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
HR‐TEM imaging and image simulation of vacancy clusters in brown diamond
Authors: Barnes R. , Bangert U. , Martineau P.
Published: September 2006

Diamonds, although famous for their sparkling colourless nature, can exhibit many colours due to imperfections in the crystal lattice. Brown diamonds, while not the favourite variety, have attracted much attention and mystery in finding the origin of the colour. The defect, which is not impurity related, can be removed with HPHT treatment. Collections of vacancies have been suggested as the source of the colour by theoretical calculations [1] and positron annihilation experiments [2, 3]. Therefore, simulations have been carried out to determine whether the suggested sizes of vacancy clusters could be seen in HR‐TEM. Substantial contrast has been revealed in defocused images. In light of the simulations, experimental defocus series have been acquired in lattice resolution for brown and colourless, natural and synthetic type IIa diamonds. A small‐scale patchiness is apparent in the lattice images of brown but not of colourless diamond. Further analysis, including simulations of multiple vacancy clusters, suggests this contrast in brown diamond could be due to many irregularly distributed vacancy clusters. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)