bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nanofiber formation of amphiphilic cyclic tri‐β‐peptide
Authors: Ishihara Yusuke , Kimura Shunsaku 
Published: January 2010

AbstractA novel amphiphilic cyclic peptide composed of two β‐glucosamino acids and one trans‐2‐aminocyclohexylcarboxylic acid was synthesized and investigated on assembly formation. The cyclic tri‐β‐peptide was self‐assembled into rodlike crystals or nanofibers depending on preparative conditions. The rodlike crystals showed a layer spacing of 4.8 Å along the long axis, and columnar spacings of 10.8 and 21.5 Å by electron diffraction analysis along the short axis. The former confirms the columnar structure upon molecular stacking, and the latter indicates triple bundle formation of the columnar assemblies. Fourier transform infrared (FT‐IR) measurement of the fibrous assembly showed formation of homogeneous hydrogen bonds among amide groups, also supporting the molecular stacking of cyclic β‐peptides. Straight nanofibers with uniform diameter were also uniquely obtained. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Carbon nanostructures from Fe–C nanocomposites by activated CVD methods
Authors: Fleaca Claudiu , Morjan Ion , Alexandrescu Rodica , Dumitrache Florian , Soare Iuliana , Gavrila‐Florescu Lavinia , Normand François Le , Faerber Jaques 
Published: January 2010

AbstractIron‐based core‐shell nanoparticles can present interesting catalytic properties for the growth of carbon nanostructures. We report the synthesis of various carbon nanostructures using activated chemical vapour deposition methods. These structures were analysed by Scanning Electon Microscopy (SEM) and Raman spectroscopy. Laser pyrolysis technique was used for synthesis of less than 10 nm diameter Fe‐C core‐shell catalyst nanoparticles. Acetone suspensions of Fe‐C nanoparticles were drop‐casted or spin coated onto Si(100) substrates. The consequence of hydrogen selective etching of these nanocomposites at 550 °C, followed by a treatment with a mixture of H2 and C2H2 at 700 °C (both in the presence of hot filaments) was the growth of corrugated ribbons and decorated or distorted carbon nanotubes/nanofibers. Round agglomerate nanoparticles and long and very thin nanotubes were observed on the substrates edges (protected from direct etching). By adding in similar conditions a glow discharge plasma to hot filaments, the resulted deposits contain oriented nanotubes. Due to the implication of the electric field, the presence of both plasma and hot wires seems to significantly change the specific growth conditions of carbon nanostructures towards those resulted when only incandescent filaments were used (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Development of a new indicator of pollutant loads and its application to the Chesapeake Bay watershed
Authors: Keller Troy A. , Shenk Gary W. , Williams Michael R. , Batiuk Richard A. 
Published: January 2010

AbstractPollutant load reductions are often required to restore aquatic ecosystems experiencing eutrophication. Loads can be estimated using watershed models or data from monitoring stations, however data availability can limit the timeliness or comprehensiveness of the load estimates. We developed an approach to address this challenge that used watershed model results to estimate the proportion of annual nonpoint source nitrogen (N), phosphorus (P) and sediment (Sed) loads derived from unmonitored catchments. This proportion was multiplied by the nonpoint portion of United States Geological Survey (USGS) estimated annual river loads to account for annual variation in hydrologic conditions. Total loads were calculated as the sum of measured river loads, reported point sources from unmonitored areas and the estimated nonpoint source loads from unmonitored catchments. We applied this approach to the Chesapeake Bay because of its socio‐economic and ecological importance. Median watershed loads for N, P and Sed were 140, 6.4 and 3030 Mg year−1, respectively (1990–2004). Nonpoint source loads from the monitored areas constituted the greatest source of N, P and Sed (55, 47 and 74% respectively) to the Bay. The high N, P and Sed yield rates (7.3, 0.38 and 99 kg ha−1 year−1, respectively) from nonpoint loads originating from unmonitored areas near the Bay resulted in 25, 32 and 26% (N, P and Sed, respectively) of the Bay's total loads (excluding direct atmospheric deposition, shoreline erosion and oceanic inputs). Disproportionately high loads of P and Seds were associated with years that experienced elevated discharge whereas N loads were directly related to discharge. Error estimates indicated that our methods were most reliable for N (±6%) but reasonable for P (±22%) and provide an effective technique for the timely estimation of pollutant loads from watersheds with unmonitored catchments. Management strategies that decrease N deposition and reduce runoff to control P and Sed transport will effectively reduce pollutant loads. Published in 2010 by John Wiley & Sons, Ltd.
Testing one premise of scientific inquiry in science classrooms: Examining students' scientific explanations and student learning
Authors: Ruiz‐Primo Maria Araceli , Li Min , Tsai Shin‐Ping , Schneider Julie 
Published: January 2010

AbstractIn this study, we analyzed the quality of students' written scientific explanations found in notebooks and explored the link between the quality of the explanations and students' learning. We propose an approach to systematically analyzing and scoring the quality of students' explanations based on three components: claim, evidence to support it, and a reasoning that justifies the link between the claim and the evidence. We collected students' science notebooks from eight science inquiry‐based middle‐school classrooms in five states. All classrooms implemented the same scientific‐inquiry based curriculum. The study focuses on one of the implemented investigations and the students' explanations that resulted from it. Nine students' notebooks were selected within each classroom. Therefore, a total of 72 students' notebooks were analyzed and scored using the proposed approach. Quality of students' explanations was linked with students' performance in different types of assessments administered as the end‐of‐unit test: multiple‐choice test, predict‐observe‐explain, performance assessment, and a short open‐ended question. Results indicated that: (a) Students' written explanations can be reliably scored with the proposed approach. (b) Constructing explanations were not widely implemented in the classrooms studied despite its significance in the context of inquiry‐based science instruction. (c) Overall, a low percentage of students (18%) provided explanations with the three expected components. The majority of the sample (40%) provided only claims without any supporting data or reasoning. And (d) the magnitude of the correlations between students' quality of explanations and their performance, were all positive but varied in magnitude according to the type of assessment. We concluded that engaging students in the construction of high quality explanations may be related to higher levels of student performance. The opportunities to construct explanations in science‐inquiry based classrooms, however, seem to be limited. © 2010 Wiley Periodicals, Inc. J Res Sci Teach 47: 583–608, 2010
A link layer protocol and link‐state routing protocol suite for multi‐channelad hocnetworks
Authors: Yoon Wonyong , Vaidya N. H. 
Published: January 2010

AbstractWe propose a link layer protocol and link‐state routing protocol suite for multi‐channelad hocnetworks. The proposed protocol suite addresses several practical issues that arise when nodes equipped with two radio interfaces want to utilize available channels. The routing layer makes a hybrid channel assignment where one interface is fixed and the other is switchable. Based on that, the routing layer runs a shortest path routing algorithm augmented with channel diversity. The link layer implements a slotted structure to minimize broadcast overhead inherent to multi‐channel networks. By using flow‐ and packet‐level simulators, we make some important observations. First, a hybrid channel assignment is good for connectivity and amenable to shortest‐path routing. Second, seeking a shortest‐path can be a better routing strategy in terms of global system throughput than complex channel‐diverse routing. Third, channel switching delay is not a throttling factor in terms of global system throughput. Copyright © 2010 John Wiley & Sons, Ltd.
Cleft Lip and Palate as a Cost‐effective Health Care Treatment in the Developing World
Authors: Magee William P. , Vander Burg Richard , Hatcher Kristin Ward 
Published: January 2010

AbstractBackgroundThe considerable number of surgical procedures performed each year, as well as the significant burden of surgical disease globally, have brought surgery into the arena of public health concerns. Several articles have shown the cost‐effectiveness of surgical interventions in the developing world. The authors suggest that surgery has an important role in global public health, specifically through international volunteer surgical missions as a vehicle for delivery.MethodsEight Operation Smile medical missions from 2008 are analyzed using the disability‐adjusted life year (DALY) framework and disability weights from the life tables of the first Disease Control Priorities Project (DCP1). The DCP1 life tables suggest that the entire burden of disease from a cleft lip and palate is incurred within the first 4 years of life. The same group of missions is analyzed using life tables modified by the authors to reflect the disability associated with cleft lip and palate that goes beyond the first 5 years of life.ResultsUsing the DCP1 life tables, the cost per patient during the eight Operation Smile missions analyzed was $278 and $1827 with an average of $796. Using the life tables modified by the authors, the cost per patient was between $7.36 and $96.04 (average $33.94).ConclusionsThe absence of disability weights for untreated cleft lip and palate after the fifth year of life does not fit with the reality of living with an unrepaired cleft lip or palate. The authors conclude that secondary interventions alleviate disability and should enable an individual to approach a zero residual disability weight.
Factors Predicting Outcome of Total Thyroidectomy in Young Patients with Multiple Endocrine Neoplasia Type 2: A Nationwide Long‐Term Follow‐up Study
Authors: Schreinemakers Jennifer M. J. , Vriens Menno R. , Valk Gerlof D. , de Groot Jan‐Willem B. , Plukker John T. , Bax Klaas (N.) M. A. , Hamming Jaap F. , van der Luijt Rob B. , Aronson Daniel C. , Borel Rinkes Inne H. M. 
Published: January 2010

AbstractBackgroundMultiple endocrine neoplasia type 2 (MEN 2) is caused by a RET mutation in chromosome 10. All MEN 2 patients develop medullary thyroid carcinoma (MTC). The age‐related risk of MTC is associated with the type of RET mutation. Our aim was to identify prognostic factors associated with recurrent MTC in MEN 2 patients.MethodsIn a nationwide case–control study, all patients who underwent total thyroidectomy in the Netherlands under the age of 20 years were classified into standard (1), high (2), or very high risk (3) for MTC based on RET‐mutation type. Disease‐free patients were compared with those with recurrent disease.ResultsA total of 93 patients were included in the study. Sixty‐six percent had MTC on histology, the youngest being 1 year old. Codon 634 was most affected. Sixteen (18%) patients had persistent or recurrent disease, one of whom died. Significantly associated determinants of outcome in univariate analysis were higher age at surgery, no age‐appropriate prophylactic surgery according to risk level, elevated preoperative calcitonin levels, affected codon, and the presence of lymph node metastases at surgery. On multivariate analysis only age of surgery was the single independent factor associated with persistent disease.ConclusionsProphylactic thyroidectomy beyond the recommended age is associated with persistent/recurrent disease. In addition, codon 634 mutation is associated with a high risk of recurrence requiring early surgery for all these patients.
Tetrahydrobiopterin responsiveness after extended loading test of 12 Danish PKU patients with the Y414C mutation
Authors: Nielsen Jytte Bieber , Nielsen Karin E. , Güttler Flemming 
Published: January 2010

AbstractPhenylketonuria (PKU) is an inherited metabolic disease characterized by phenylalanine (Phe) accumulation due to defects in the enzyme phenylalanine hydroxylase (PAH). Phe accumulation can lead to cognitive impairment. Some individuals with PKU respond to tetrahydrobiopterin (BH4) treatment, the natural cofactor of PAH, by a reduction in blood Phe concentrations. We tested 12 patients with PKU, 8–29 years of age, all carrying the common Y414C mutation in the PAH gene. Three were homozygous and nine were compound heterozygous, with the second mutation being a putative null mutation. During the study period, genuine protein was increased to approximately 1 g/kg. The patients were treated with 20, 10, and 5 mg BH4/kg/day for 1 week on each dose, starting with 20 mg/kg. A positive response was defined as a decline in blood Phe > 30%. Blood Phe was measured four times a week. Nonresponding children were excluded from the study. Eleven of 12 patients had a positive response with 20 mg/kg, 5/10 responded on 10 mg/kg, and 1/9 on 5 mg/kg. Two were late responders, with a response on 20 mg/kg after >48 h. We could confirm the previously reported inconsistent responsiveness of Y414C in the nine heterozygous patients, whereas the three homozygous patients had early median Phe declines of 73%, 51%, and 27%, respectively, on the three different doses. The varying responses despite uniform trial conditions and genotypes may be due to individual differences in BH4 absorption or metabolism. No side effects were observed.
Nonlinear diffusion with a bounded stationary level surface
Authors: Magnanini Rolando , Sakaguchi Shigeru 
Published: January 2010

We consider nonlinear diffusion of some substance in a container (not necessarily bounded) with bounded boundary of class

C^{2}

. Suppose that, initially, the container is empty and, at all times, the substance at its boundary is kept at density 1. We show that, if the container contains a proper

C^{2}

-subdomain on whose boundary the substance has constant density at each given time, then the boundary of the container must be a sphere. We also consider nonlinear diffusion in the whole

\mathbb{R}^{N}

of some substance whose density is initially a characteristic function of the complement of a domain with bounded

C^{2}

boundary, and obtain similar results. These results are also extended to the heat flow in the sphere

\mathbb{S}^{N}

and the hyperbolic space

\mathbb{H}^{N}

.

Résumé

Nous considérons la diffusion non linéaire d'une substance dans un récipient (pas nécessairement borné) avec frontière bornée de classe

C^{2}

. Supposons qu'initialement, le récipient soit vide et, à sa frontière, la densité de la substance soit gardée à tout moment égale à 1. Nous montrons que, si le récipient contient un sous-domaine

C^{2}

propre à la frontière duquel la substance est gardée à tout moment à densité constante, alors la frontière du récipient doit être une sphère. Nous considérons aussi la diffusion non linéaire dans tout

\mathbb{R}^{N}

d'une substance dont la densité est initialement une fonction caractéristique du complémentaire d'un domaine ayant la frontière bornée et

C^{2}

, et nous obtenons des résultats semblables. Ces résultats sont aussi généralisés au cas du flux de chaleur dans la sphère

\mathbb{S}^{N}

et l'espace hyperbolique

\mathbb{H}^{N}

.
White matter integrity and cortical metabolic associations in aging and dementia
Authors: Kuczynski Beth , Targan Elizabeth , Madison Cindee , Weiner Michael , Zhang Yu , Reed Bruce , Chui Helena C. , Jagust William 
Published: January 2010

AbstractBackgroundStudies show that white matter hyperintensities, regardless of location, primarily affect frontal lobe metabolism and function. This report investigated how regional white matter integrity (measured as fractional anisotropy [FA]) relates to brain metabolism, to unravel the complex relationship between white matter changes and brain metabolism.ObjectiveTo elucidate the relationship between white matter integrity and gray matter metabolism using diffusion tensor imaging and fluorodeoxyglucose‐positron emission tomography in a cohort of 16 subjects ranging from normal to demented (age, >55 years).MethodsMean FA values from white matter regions underlying the medial prefrontal, inferior‐lateral prefrontal, parietal association, and posterior temporal areas and the corpus callosum were regressed with glucose metabolism (by positron emission tomography), using statistical parametric mapping (P < 0.005; voxel cluster, >100). Regional cerebral glucose metabolism was the primary outcome measure. According to our hypothesis, those hypometabolic cortical regions affected by Alzheimer's disease would correlate with a lower FA of associated tracks.ResultsOur data show inter‐regional positive correlations between FA and gray matter metabolism for the prefrontal cortex, temporal, and parietal regions. Our results suggest that left prefrontal FA is associated with left temporal and parietal metabolism. Further, left posterior temporal FA correlated with left prefrontal metabolism. Finally, bilateral parietal FA correlated with bilateral temporal metabolism.ConclusionsThese regions are associated with cognitive processes affected in Alzheimer's disease and cerebrovascular disease, suggesting a link with white matter degeneration and gray matter hypometabolism. Therefore, cortical function and white matter degeneration are related in aging and dementia.
Subtypes of depression among patients with Alzheimer's disease and other dementias
Authors: Castilla-Puentes Ruby C. , Habeych Miguel E. 
Published: January 2010

ObjectivesWe compared the prevalence of subtypes of depression in patients with Alzheimer's disease (AD), vascular dementia (VaD), and unspecified dementia (UD).MethodsUsing the Integrated Healthcare Information Services database, we conducted an analysis of subtypes of depression (major depressive disorder, depressive disorder not otherwise specified, dysthymic disorder; depressive psychosis, and adjustment disorder depressive) among patients with AD, VaD, and UD. Six thousand four hundred and forty patients aged 60 years or older with dementia (2947 with AD, 725 with VaD, and 2768 with UD) were identified from January 1 to December 31, 2001. Both subtypes of depression and dementia subgroups were diagnosed using criteria from the International Classification of Diseases, 9th version.ResultsThe overall prevalence of depressive disorders was 27.41%. The prevalence of depressive disorders was significantly higher in VaD (44.14%) and UD (32.48%) patients compared with AD (18.53%, P < .0001) patients. The AD patients had the lowest prevalence of all subtypes of depression. The VaD patients, compared with both AD and UD (P < .005), had a significantly higher prevalence of: 1) depressive disorder not otherwise specified, 2) major depressive disorder, and 3) dysthymic disorder. Adjustment disorder with depressive symptoms was more common in the UD subgroup, whereas the rate of depressive psychosis was similar in all dementia subgroupsConclusionsThis study supports the view that depressive disorders are more prevalent in VaD compared with UD and AD, and provides indicators to the clinician for further evaluation of depression in dementia subgroups
Toward an Alzheimer's disease diagnosis via high‐resolution blood gene expression
Authors: Fehlbaum-Beurdeley Pascale , Jarrige-Le Prado Anne Charlotte , Pallares Diego , Carrière Jennifer , Guihal Caroline , Soucaille Cyril , Rouet Fabien , Drouin Dominique , Sol Olivier , Jordan Heather , Wu Darong , Lei Ling , Einstein Richard , Schweighoffer Fabien , Bracco Laurent 
Published: January 2010

BackgroundThere is a significant need for reliable molecular biomarkers to aid in Alzheimer's disease (AD) clinical diagnosis.MethodsWe performed a genome‐wide investigation of the human transcriptome, taking into account the discriminatory power of splice variations from the blood of 80 AD patients and 70 nondemented control (NDC) individuals.ResultsWe characterized a blood RNA signature composed of 170 oligonucleotide probe sets associated with 133 genes that can correctly distinguish AD patients from NDC with a sensitivity of 100% and specificity of 96%. Functionally, this signature highlights genes involved in pathways that were associated with macrophages and lymphocytes within AD patients: Transforming growth factor (TGF‐β) signaling, oxidative stress, innate immunity and inflammation, cholesterol homeostasis, and lipid‐raft perturbation, whereas other genes may also provide new insights in the biology of AD.ConclusionsThis study provides proof‐of‐concept that whole‐blood profiling can generate an AD‐associated classification signature via the specific relative expression of biologically relevant RNAs. Such a signature will need to be validated with extended patient cohorts, and evaluated to learn whether it can differentiate AD from others types of dementia.
Efficacy of a medical food in mild Alzheimer's disease: A randomized, controlled trial
Authors: Scheltens Philip , Kamphuis Patrick J.G.H. , Verhey Frans R.J. , Olde Rikkert Marcel G.M. , Wurtman Richard J. , Wilkinson David , Twisk Jos W.R. , Kurz Alexander 
Published: January 2010

ObjectiveTo investigate the effect of a medical food on cognitive function in people with mild Alzheimer's disease (AD).MethodsA total of 225 drug‐naïve AD patients participated in this randomized, double‐blind controlled trial. Patients were randomized to active product, Souvenaid, or a control drink, taken once‐daily for 12 weeks. Primary outcome measures were the delayed verbal recall task of the Wechsler Memory Scale–revised, and the 13‐item modified Alzheimer's Disease Assessment Scale–cognitive subscale at week 12.ResultsAt 12 weeks, significant improvement in the delayed verbal recall task was noted in the active group compared with control (P = .021). Modified Alzheimer's Disease Assessment Scale–cognitive subscale and other outcome scores (e.g., Clinician Interview Based Impression of Change plus Caregiver Input, 12‐item Neuropsychiatric Inventory, Alzheimer's disease Co‐operative Study–Activities of Daily Living, Quality of Life in Alzheimer's Disease) were unchanged. The control group neither deteriorated nor improved. Compliance was excellent (95%) and the product was well tolerated.ConclusionsSupplementation with a medical food including phosphatide precursors and cofactors for 12 weeks improved memory (delayed verbal recall) in mild AD patients. This proof‐of‐concept study justifies further clinical trials.
Nasal septal abscess and facial cellulitis caused by community-acquired methicillin-resistant Staphylococcus aureus
Authors: Cheng L-H , Kang B-H 
Published: January 2010

AbstractObjective:Community-acquired methicillin-resistant Staphylococcus aureus is emerging as an important pathogen. However, methicillin-resistant Staphylococcus aureus rarely causes nasal septal abscess.Case report:We present a case of severe, community-acquired, methicillin-resistant Staphylococcus aureus infection causing rapidly progressing sinusitis, nasal septal abscess and facial cellulitis.Conclusion:This report serves to remind the clinician of the expanding spectrum of severe infections caused by methicillin-resistant Staphylococcus aureus, all requiring prompt diagnosis and appropriate medical and/or surgical management.
Effective charge of photons and plasmons
Authors: MENDONÇA J. T. , SERBETO A. , ALI S. 
Published: January 2010

AbstractWe review the concept of photon effective charge in a plasma, and extend it to the case of longitudinal photons or plasmons. A simple electrostatic fluid model is considered in a non-magnetized and non-relativistic plasma. The contribution of the ions to the plasmon charge is also considered.