bluuebunny/crossref_metadata_2025_split huggingface dataset:
A syndrome of irreversible leukoencephalopathy following pediatric allogeneic bone marrow transplantation
Authors: Minn A. Yuriko , Fisher Paul G. , Barnes Patrick D. , Dahl Gary V. 
Published: December 2005

AbstractBackgroundDespite decreases in overall mortality following bone marrow transplantation (BMT), a number of complications such as neurotoxicity have been described and often associated with immunosuppressive agents. The syndrome of reversible posterior leukoencephalopathy has been described in patients receiving cyclosporin and FK‐506. We report here a subset of children who developed a syndrome of previously undescribed irreversible leukoencephalopathy following allogeneic BMT.Patients and MethodsBetween 1996 and 2002, 138 pediatric patients received an allogeneic BMT at Lucile Salter Packard Children's Hospital at Stanford. Six cases of irreversible leukoencephalopathy were observed. Cases were defined as children who exhibited progressive and continued, severe neurologic deterioration lasting greater than 2 weeks and consistent with non‐localizing, central nervous system abnormalities. Medical records and magnetic resonance images (MRIs) were reviewed.ResultsMedian age of the affected patients at BMT was 7.8 years. All six received cyclosporin, but none had elevated drug levels. Encephalopathy occurred at a median of 53 days (range 14–77) following BMT. Symptoms at onset of leukoenceophalopathy included confusion and altered mental status, sluggish pupillary responses, abnormal movements, and seizures. Two patients died during their neurologic decline. Four patients remain alive with persistent encephalopathy. MRI showed abnormalities in all patients including periventricular or subcortical white matter involvement in all, and basal ganglia lesions in three.ConclusionsWe report a syndrome of irreversible neurologic deficits and cerebral white matter abnormalities following allogeneic BMT, yet not associated with elevated cyclosporin levels. A precise mechanism for this syndrome is lacking and warrants further consideration. Pediatr Blood Cancer 2007;48:213–217. © 2006 Wiley‐Liss, Inc.
Ceric(IV) ion‐induced graft copolymerization of acrylamide and ethyl acrylate onto cellulose
Authors: Gupta Kailash C , Khandekar Keerti 
Published: December 2005

AbstractGraft copolymerization of acrylamide (AAm) and ethyl acrylate (EA) onto cellulose has been carried out from their binary mixtures using ceric ammonium nitrate (CAN) as an initiator in the presence of nitric acid at 25 ± 1 °C. The extent of acrylamide grafting increased in the presence of the EA comonomer. The composition of the grafted chains (FAAm = 0.52) was found to be constant during the feed molarity variation from 7.5 × 10−2 to 60.0 × 10−2 mol L−1, whereas the composition of the grafted chains (FAAm) was found to be dependent on feed composition (fAAm) and reaction temperature. The effects of ceric(IV) ion concentration, reaction time and temperature on the grafting parameters have been studied. The grafting parameters showed an increasing trend up to 6.0 × 10−3 mol L−1 concentration of CAN at a feed molarity of 30.0 × 10−2 mol L−1 and showed a decreasing trend on further increasing the concentration of CAN (>6.0 × 10−3 mol L−1) at a constant concentration of nitric acid (5.0 × 10−2 mol L−1). The composition of the grafted chains (FAAm) was determined by IR spectroscopy and nitrogen content and the data obtained then used to determine the reactivity ratios of the acrylamide (r1) and ethyl acrylate (r2) comonomers by using a Mayo and Lewis plot. The reactivity ratios of acrylamide and ethyl acrylate were found to be r1 = 0.54 and r2 = 1.10, respectively, and hence the sequence lengths of acrylamide (m̄M1) and ethyl acrylate (m̄M2) in the grafted chains are arranged in an alternating form, as the product of the reactivity ratios of acrylamide and ethyl acrylate (r1 × r2) is less than unity. The rate of graft copolymerization of the comonomers onto cellulose was found to be dependant on the ‘squares’ of the concentrations of the comonomers and on the ‘square root’ of the concentration of ceric ammonium nitrate. The energy of activation (ΔEa) of graft copolymerzation was found to be 5.57 kJ mol−1 within the temperature range from 15 to 50 °C. On the basis of the results, suitable reaction steps have been proposed for the graft copolymerzation of acrylamide and ethyl acrylate comonomers from their mixtures. Copyright © 2005 Society of Chemical Industry
Molecular design, synthesis, and electro‐optic properties of novel Y‐type polyesters with high thermal stability of second harmonic generation
Authors: Lee Ju‐Yeon , Jung Won‐Taek , Lee Won‐Jung 
Published: December 2005

Abstract3,4‐Di‐(2′‐hydroxyethoxy)‐4′‐nitrostilbene was prepared and condensed with terephthaloyl chloride, adipoyl chloride, and sebacoyl chloride to yield novel Y‐type polyesters containing NLO‐chromophore dioxynitrostilbenyl groups, which constituted parts of the polymer backbone. Polymers were found soluble in common organic solvents such as acetone and N,N‐dimethylformamide. They showed thermal stability up to 300 °C in thermogravimetric analysis with glass‐transition temperatures obtained from differential scanning calorimetry in the range 110–152 °C. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at a 1064 cm−1 fundamental wavelength were around 3.51 × 10−8 esu. The dipole alignment exhibited high thermal stability even at 10 °C higher than the glass‐transition temperature, and there was no SHG decay below 120 °C for one of these polymers due to the partial main‐chain character of polymer structure, which was acceptable for NLO device applications. Copyright © 2005 Society of Chemical Industry
Study on the nonisothermal crystallization behavior of poly(vinyl alcohol)/attapulgite nanocomposites by DSC analysis
Authors: Peng Zhiqin , Chen Dajun 
Published: December 2005

AbstractAttapulgite (AT)‐reinforced poly(vinyl alcohol) (PVA) nanocomposite films were prepared by solution‐casting technique. The nonisothermal crystallization behaviors of PVA bulk and PVA/AT nanocomposites have been investigated by differential scanning calorimetry (DSC). It has been found that the uniformly dispersed AT nanorods in the matrix have great influence on the glass transition temperature and crystallization behavior of PVA matrix. The Jeziorny method has been employed to analyze the DSC data. The results show that Jeziorny method could describe this system very well. Comparing with the PVA bulk, PVA/AT nanocomposites have higher crystallinity Xt, shorter semicrystallization time t1/2, and higher crystallization rate constant Zc. It can be concluded that AT can be used as an effective nucleating agent and has effects on the growth of crystallites in the crystallization process of PVA matrix. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 534–540, 2006
Formation of oriented polypeptides on Au(111) surface depends on the secondary structure controlled by peptide length
Authors: Sakurai Toshihiko , Oka Sayaka , Kubo Atsushi , Nishiyama Katsuhiko , Taniguchi Isao 
Published: December 2005

AbstractWe synthesized three different lengths of poly(L‐lysine) containing an ‐SH group at the terminal (PLLn‐SH, n (polymerization degree) = 4, 10, 30) and adsorbed them on an Au(111) surface. To analyze the formation process and the structure of self‐assembled monolayers (SAMs), we used atomic force microscopy (AFM) and Fourier transform infrared reflection absorption spectra (FT‐IR RAS). At the initial stage of SAM growth, formation of nanosize domains was confirmed by AFM imaging. The α‐helical PLL30‐SH exhibited a well‐defined SAM structure after adsorption reached equilibrium. The α‐helical PLL30‐SH was almost perpendicular to the gold surface and exhibited interesting molecular packing due to the secondary structure of PLL30‐SH and the underlying Au(111) array. The tilt angle of the helix axis from the substrate normal was estimated to be about 50° (AFM) and 44° (FT‐IR RAS) respectively. On the other hand, PLL4‐SH and PLL10‐SH formed β‐sheet‐type SAMs on the Au(111) surface based on the structure determined by FT‐IR RAS spectrum. Copyright © 2005 European Peptide Society and John Wiley & Sons, Ltd.
Characterization of N‐glycans of recombinant human thyrotropin using mass spectrometry
Authors: Morelle Willy , Donadio Sandrine , Ronin Catherine , Michalski Jean‐Claude 
Published: December 2005

AbstractThyroid‐stimulating hormone is a vital component of the regulatory mechanism that maintains the structure and function of the thyroid gland and governs thyroid hormone release. In this paper we report the first detailed structural characterization of the N‐linked oligosaccharides of recombinant human thyroid‐stimulating hormone (rhTSH). Using a strategy combining mass spectrometric analysis and sequential exoglycosidase digestion, we have defined the structures of the N‐glycans released from recombinant human thyrotropin by peptide N‐glycosidase F. All glycans are complex‐type glycans and are mainly of the bi‐ and triantennary type with variable degrees of fucosylation and sialylation. The major non‐reducing epitope in the complex‐type glycans is: NeuAcα2‐3Galβ1‐4GlcNAc (sialylated LacNAc). The carbohydrate microheterogeneity at the three glycosylation sites was studied using reversed‐phase high‐performance liquid chromatography (RP‐HPLC), concanavalin A affinity chromatography and mass spectrometric techniques, including both matrix‐assisted laser desorption/ionization (MALDI) and electrospray. rhTSH was reduced, carboxymethylated and then digested with trypsin. The mixture of peptides and glycopeptides was subjected to RP‐HPLC and the structures of the glycopeptides were determined by MALDI in conjunction with on‐target exoglycosidase digestions. After PNGase F digestion, the peptide moiety of the glycopeptide was determined by the presence of the b‐ and y‐series ions derived from its amino acid sequence in the quadrupole time‐of‐flight tandem mass (QTOF‐MS/MS) spectrum. Glycosylation sites Asn‐α52 and Asn‐α78 contain mainly bi‐ and triantennary complex‐type glycans. Only glycosylation site Asn‐α52 bears fucosylated N‐glycans. Minor tetraantennary complex structures were also observed on both glycosylation sites. Profiling of the carbohydrate moieties of Asn‐β23 indicates a large heterogeneity. Bi‐, tri‐, and tetraantennary N‐glycans were present at this site. These data demonstrate site‐specificity of glycosylation in the α subunit but not in the β subunit of rhTSH with Asn‐α52 bearing essentially di‐ and triantennary glycans with or without core fucosylation and bi‐ and triantennary glycans with no core fucosylation being attached to Asn‐α78. Copyright © 2005 John Wiley & Sons, Ltd.
Semi‐parametric accelerated failure time regression analysis with application to interval‐censored HIV/AIDS data
Authors: Xue Hongqi , Lam K. F. , Cowling Benjamin J. , de Wolf Frank 
Published: December 2005

AbstractThis paper demonstrates a way to investigate a potentially non‐linear relationship between an interval‐censored response variable and a continuously distributed explanatory variable. A potentially non‐linear effect of a continuous explanatory variable on the response is incorporated into an accelerated failure time model, forming a partial linear model. A sieve maximum likelihood estimator (MLE) is suggested to simultaneously estimate all the parameters. The sieve MLE is shown to be asymptotically efficient and normally distributed. Simulation studies show that the proposed estimators for the scale and regression parameters are robust and efficient, and the estimator for the non‐linear function is able to capture the shape of a variety of smooth non‐linear functions. The model is applied to observational HIV data, where the response variable is the time to suppression of HIV viral load after initiation of antiretroviral therapy, and baseline viral load is investigated as a potentially non‐linear effect. Copyright © 2005 John Wiley & Sons, Ltd.
Minding your distance: how management consulting firms use service marks to position competitively
Authors: Semadeni Matthew 
Published: December 2005

AbstractThis research examines the dyadic dynamics of positioning (i.e., determining where to locate relative to rivals) of services by consulting firms. Positioning near to or far from competitors offers both advantages and disadvantages in terms of competition, legitimacy, uncertainty, and spillovers, with recent research suggesting that firms seek balance between these various forces. Using a sample of service mark filings by consulting firms, I examine the effects of similarity, age, size, and prospective services on service positioning. Results indicate that positioning is both dyadic and multidimensional in nature, with firms maximizing the advantages of positioning either near or far, while minimizing the disadvantages. Copyright © 2006 John Wiley & Sons, Ltd.
Regen‐Wind‐induzierte Schwingungen – Ein Berechnungsmodell auf der Grundlage der neuesten Erkenntnisse
Authors: Schwarzkopf Dieter , Sedlacek Gerhard 
Published: December 2005

AbstractRegen‐Wind‐induzierte Schwingungen von zylindrischen Bauteilen wie z. B. Brückenseilen oder Hängern entstehen, wenn diese gleichzeitig Regen und Wind ausgesetzt sind. Dieses Phänomen ist bei Brückenbauern bekannt und gefürchtet – letzteres insbesondere aufgrund spektakulärer Ereignisse wie zum Beispiel der Sperrung der Erasmusbrücke in Rotterdam kurz nach ihrer Eröffnung oder den Schäden an der Elbebrücke Dömitz.Neben der Existenz von Regen und Wind spielen auch Parameter wie Regenmenge, Windgeschwindigkeit, Windrichtung etc. eine entscheidende Rolle. Einmal angeregte Regen‐Wind‐induzierte Schwingungen klingen direkt wieder ab, sobald sich die Regenintensität oder die Windgeschwindigkeit stark ändern oder die Windrichtung wechselt. Bei diesem Schwingungsphänomen handelt es sich um selbsterregte Schwingungen, bei denen das Zusammenwirken der bewegten Seile oder Hänger, der daran ablaufenden Wasserrinnsale und des Windes entscheidenden Einfluß hat. Diese Art von Schwingungen ist nicht neu, jedoch der Erregermechanismus ist bislang noch wenig erforscht, und es gibt noch kein Berechnungsverfahren, welches es erlaubt, die auftretenden Amplituden zu bestimmen.
Baupraktische Sicherheitsnachweise gegen winderregte Schwingungen von Brücken und Türmen
Authors: Herzog Max 
Published: December 2005

AbstractDie Entwicklung und der gegenwärtige Stand baupraktischer Sicherheitsnachweise gegen winderregte Schwingungen von Hänge‐ und Schrägseilbrücken sowie von Türmen werden im folgenden Beitrag erläutert und anhand von drei Zahlenbeispielen aus der Praxis mit dem in situ‐Verhalten verglichen.
Eine Finite‐Elemente‐Lösung auf der Basis eines erweiterten eindimensionalen Querschnittselementes für die freie Torsion dünnwandiger prismatischer Stäbe
Authors: Eilering Siegfried 
Published: December 2005

AbstractEs wird eine Finite‐Elemente‐Lösung auf der Basis eines erweiterten Querschnittselementes zur Berechnung der Wölbfunktion und der von ihr abhängigen Torsionskennwerte und Torsionsschubspannungen für dünnwandige prismatische Stäbe unter freier Torsion vorgestellt. Das formulierte finite Zwei‐Knoten‐Element mit sechs Elementfreiheitsgraden ist durch Einbeziehung der Verdrehung um die Elementachse in der Lage, den linearen Term der Veränderlichkeit der Verwölbung quer zur Elementachse zu erfassen. Aufgrund dessen werden im Gegensatz zum einfachen Zwei‐Knoten‐Element mit nur zwei Elementfreiheitsgraden, das nur die über die Wanddicke konstanten Schubspannungen aus den Kreisschubflüssen der geschlossenen Profilteile liefert, auch die diese überlagernden, über die Wanddicke linear veränderlichen Schubspannungen des aufgeschnittenen Profils erfaßt.
First‐trimester maternal serum level of pregnancy‐associated plasma protein‐A is an independent predictor of fetal maxillary bone length
Authors: Leung T. Y. , Chan L. W. , Leung T. N. , Fung T. Y. , Sahota D. S. , Lau T. K. 
Published: December 2005

AbstractObjectiveTo derive a nomogram of fetal maxillary bone length (MAX) for a Chinese population and to study whether first‐trimester maternal serum levels of pregnancy‐associated plasma protein‐A (PAPP‐A) is an independent predictor of fetal MAX.MethodsThis was a prospective observational study over 10 months examining Chinese women with a singleton pregnancy who attended the first‐trimester screening program for Down syndrome. The subjects had the fetal crown–rump length (CRL), nuchal translucency, MAX, maternal serum PAPP‐A and free beta‐human chorionic gonadotropin (fβ‐hCG) levels measured. A nomogram of MAX was derived using normal pregnancies with reliable dates. The correlations between MAX, CRL, PAPP‐A and fβ‐hCG levels were studied, after correction for gestational dependency using Z‐score transformation for the ultrasound markers (Z‐MAX and Z‐CRL), and logarithmic transformation of multiple of gestation‐specific medians for the biochemical markers (log10PAPP‐A multiples of the median (MoM) and log10fβ‐hCG MoM), using the Pearson test and multiple regression analysis.ResultsDuring the study period, 607 Chinese women met the inclusion criteria. The mean gestational age at the first‐trimester screening was 12 + 4 weeks (SD, 4 days). Curve estimation analysis showed that a linear relationship fit best between MAX and CRL (MAX (mm) = −0.01 + 0.101 * CRL (mm); r = 0.826; P < 0.0001), and between MAX and gestational age (MAX (mm) = −8.465 + 0.170 * gestational age (day); r = 0.754; SD = 0.71; P < 0.0001). There were significant positive correlations between Z‐MAX and Z‐CRL (r = 0.627; P = < 0.0001), Z‐MAX and log10PAPP‐A MoM (r = 0.239; P = < 0.0001). Multiple regression analysis showed that both Z‐CRL (P = < 0.0001) and log10 PAPP‐A MoM (P = 0.048) were independent predictors for Z‐MAX.ConclusionBoth CRL and maternal levels of PAPP‐A are independent predictors of the fetal MAX measured during the first trimester. The positive correlation between PAPP‐A levels and fetal MAX is consistent with the known biological function of PAPP‐A on bone growth. This association must be adjusted for when both PAPP‐A and MAX are combined for screening of Down syndrome. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Repercussions of castration and vasectomy on the ductal system of the rat ventral prostate
Authors: Pereira S. , Martinez M. , Martinez F.E. , Júnior W. Mello 
Published: December 2005

AbstractDiseases, such as cancer and benign prostatic hyperplasia, are related to disruption of the mechanism regulating the balance between cell proliferation and apoptosis in prostatic cells. Since castration and vasectomy might alter that balance, this study evaluates the cell proliferation, apoptosis and height of the secretory epithelium of the ventral‐prostate ductal system post‐castration and vasectomy. Immunohistochemical (PCNA and Ki67), cytochemical (Fuelgen reaction) and morphometric investigation have been carried out. Cell proliferation indices decreased significantly in both regions of the ventral‐prostate ductal system after castration compared to the sham‐operated group. The apoptotic index increased significantly after 48 h, declining 7 days post‐castration. The cell proliferation indices did not differ after 48 h significantly; however, they increased 7 days post‐vasectomy in both regions. The apoptotic index did not differ significantly in either time post‐vasectomy. Castration caused an imbalance in favor of apoptosis, whereas vasectomy caused an imbalance in favor of cell proliferation.
Reversal of scopolamine‐induced deficits with a single dose of donepezil, an acetylcholinesterase inhibitor
Authors: Snyder Peter J. , Bednar Martin M. , Cromer Jennifer R. , Maruff Paul 
Published: December 2005

BackgroundTo develop a more rapid screening paradigm for novel cognitive enhancers, the authors sought to determine the utility of a well‐known pharmacologic model of induced dementia (scopolamine challenge), paired with a sensitive neuropsychological test, for assessing the ability of a single oral dose of a current treatment for Alzheimer's disease (donepezil) to improve cognitive performance in healthy elderly subjects.MethodsThirty‐two (4 groups of 8) healthy elderly volunteers were put randomly into a double‐blind, placebo‐controlled, modified crossover design study. In Part 1, 16 subjects received donepezil (5 mg) or placebo separately in a crossover fashion. In Part 2, the remaining 2 groups of 8 subjects received scopolamine (0.3 mg subcutaneously) with each group then were assigned randomly to receive donepezil (5 mg) or placebo (in a crossover fashion) 3 hours postbaseline. A novel measure of visuospatial working memory and executive controls, the Groton Maze Learning Test (GMLT), was administered to each subject at baseline and at 2.5, 4, 5.5, 7, and 9 hours after dosing of donepezil.ResultsWith scopolamine, subjects showed slower psychomotor speed, reduced accuracy and learning efficiency, and longer time required to navigate a hidden maze. Concurrent administration of donepezil significantly reversed these deficits and resulted in a faster recovery time. In addition, single doses of donepezil alone led to improved psychomotor speed, accuracy, and learning efficiency.ConclusionsRobust effects of single‐dose donepezil on cognition can be readily observed, with the use of a complex hidden maze learning task, both with and without a scopolamine‐induced deficit model in healthy elderly adults.
Influence of logjam-formed hard points on the formation of valley-bottom landforms in an old-growth forest valley, Queets River, Washington, USA
Authors: Montgomery David R. , Abbe Tim B. 
Published: December 2005

AbstractField surveys and radiocarbon dating of buried logjams in the floodplain of an old-growth forest river demonstrate the formation of erosion-resistant “hard points” on the floodplain of the Queets River, Washington. These hard points provide refugia for development of old-growth forest patches in frequently disturbed riparian environments dominated by immature forest. Our surveys show that local bed aggradation associated with logjams not only influences channel patterns and profiles but leads to development of a patchwork of elevated landforms that can coalesce to form portions of the valley bottom with substantial (i.e., 1 to > 4 m) relief above the bankfull elevation. In addition, logjam-formed hard points promote channel avulsion, anastomosing morphology, and growth of mature patches of floodplain forest that, in turn, provide large logs needed to form more logjam-formed hard points. Hence, our findings substantiate the potential for a feedback mechanism through which hard points sustain complex channel morphology and a patchwork floodplain composed of variable-elevation surfaces. Conversely, such a feedback further implies that major changes in riparian forest characteristics associated with land use can lead to dramatic simplification in channel and floodplain morphology.