bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alzheimer's disease in Down syndrome: Neurobiology and risk
Authors: Zigman Warren B. , Lott Ira T. 
Published: October 2007

AbstractDown syndrome (DS) is characterized by increased mortality rates, both during early and later stages of life, and age‐specific mortality risk remains higher in adults with DS compared with the overall population of people with mental retardation and with typically developing populations. Causes of increased mortality rates early in life are primarily due to the increased incidence of congenital heart disease and leukemia, while causes of higher mortality rates later in life may be due to a number of factors, two of which are an increased risk for Alzheimer's disease (AD) and an apparent tendency toward premature aging. In this article, we describe the increase in lifespan for people with DS that has occurred over the past 100 years, as well as advances in the understanding of the occurrence of AD in adults with DS. Aspects of the neurobiology of AD, including the role of amyloid, oxidative stress, Cu/ZN dismutase (SOD‐1), as well as advances in neuroimaging are presented. The function of risk factors in the observed heterogeneity in the expression of AD dementia in adults with DS, as well as the need for sensitive and specific biomarkers of the clinical and pathological progressing of AD in adults with DS is considered. © 2007 Wiley‐Liss, Inc. MRDD Research Reviews 2007;13:237–246.
A cap model for partially saturated soils
Authors: Kohler R. , Hofstetter G. 
Published: October 2007

AbstractThe present paper deals with the extension of a cap model in order to describe the material behavior of partially saturated soils, in particular, of partially saturated sands and silts. The soil model is formulated in terms of two stress state variables, using net stress and matric suction and, alternatively, the average soil skeleton stress and suction, the latter playing the role of a stress‐like plastic internal variable. The yield surface, consisting of a shear failure surface and a hardening cap surface, the plastic potentials for the non‐associated flow rule and the hardening law for the cap are extended by taking into account the effects of matric suction on the material behavior. Furthermore, the third invariant of the deviatoric stress tensor is taken into account in the formulation of the yield surfaces. The developed model is validated by the numerical simulation of an extensive series of suction controlled tests for a silty sand, which were conducted at different constant values of suction. Although both versions of the soil model yield identical results for stress paths at constant values of matric suction, differences are encountered for stress paths involving wetting. Copyright © 2007 John Wiley & Sons, Ltd.
Reduced brain glutamate in patients with Parkinson's disease
Authors: Griffith H. Randall , Okonkwo Ozioma C. , O'Brien Timothy , Hollander Jan A. den 
Published: October 2007

AbstractAn understanding of the role played by glutamate (Glu) in idiopathic Parkinson's disease (PD) has remained somewhat elusive. Animal models of PD suggest that over‐activity of Glu receptors complicates the motor symptoms of PD and that Glu blockade may be a pharmacologic target in PD, whereas patient autopsy studies have proved less convincing for changes in Glu. No previous 1H MRS patient studies have documented changes in glutamate. All but one of these previous studies were performed at 1.5 T. We performed 3 T 1H MRS of the posterior cingulate gyrus in 12 non‐demented patients with PD and 12 age‐matched, neurologically normal control participants. Glu, N‐acetylaspartate (NAA) and choline‐containing compounds (Cho) measured in reference to creatine + phosphocreatine (Cr) were determined from single‐voxel proton MR spectra measured by PRESS at TE of 80 ms. The results show that the Glu/Cr ratio was reduced in patients with PD compared with controls (t = 2.54; P = 0.019), whereas no differences were observed in NAA/Cr or Cho/Cr ratios. These findings suggest that a reduction in Glu occurs in the cerebral cortex of patients with PD. 1H MRS at 3 T should be investigated in future studies as a means of tracking the course of metabolic brain changes in association with progression of disease in patients with PD. Copyright © 2007 John Wiley & Sons, Ltd.
Silica nanospheres as back surface reflectors for crystalline silicon thin‐film solar cells
Authors: Inns Daniel , Shi Lei , Aberle Armin G. 
Published: October 2007

AbstractIn this paper, fabrication of a non‐continuous silicon dioxide layer from a silica nanosphere solution followed by the deposition of an aluminium film is shown to be a low‐cost, low‐thermal‐budget method of forming a high‐quality back surface reflector (BSR) on crystalline silicon (c‐Si) thin‐film solar cells. The silica nanosphere layer has randomly spaced openings which can be used for metal‐silicon contact areas. Using glass/SiN/p+nn+c‐Si thin‐film solar cells on glass as test vehicle, the internal quantum efficiency (IQE) at long wavelengths (>900 nm) is experimentally demonstrated to more than double by the implementation of this BSR, compared to the baseline case of a full‐area Al film as BSR. The improved optical performance of the silica nanosphere/aluminium BSR is due to reduced parasitic absorption in the Al film. Copyright © 2007 John Wiley & Sons, Ltd.
Crisis response in the public schools: A survey of school psychologists' experiences and perceptions
Authors: Adamson Austin D. , Peacock Gretchen Gimpel 
Published: October 2007

AbstractIn this study, 228 school psychologists completed a survey regarding crisis intervention teams and plans. The majority of respondents indicated their schools had crisis plans (95.1%) and teams (83.6%). The most common team activities endorsed by participants involved providing direct assistance and services to students, staff, and the media. The majority of participants (93%) reported that their schools had experienced and responded to serious crises. Respondents indicated that psychological debriefing was frequently used (generic 49.1% and standardized 17.9%). Less than half of the participants (44.3%) reported that meetings were conducted with parents and community members following a crisis. Nearly all of the participants (98.2%) reported that they had some type of crisis intervention training. However, many participants suggested that additional training and practice with crisis intervention would improve schools' crisis responses. Results are discussed with implications for school psychologists to improve their schools' crisis intervention plans and teams' responses. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 749–764, 2007.
Modifying socially withdrawn behavior: A playground intervention for students with internalizing behaviors
Authors: Marchant Michelle R. , Solano Brock R. , Fisher Adam K. , Caldarella Paul , Young K. Richard , Renshaw Tyler L. 
Published: October 2007

AbstractThere is little research regarding interventions for children with internalizing behaviors in schools, both within classrooms and in nonclassroom environments. In response to this need, a nonclassroom treatment package, consisting of (a) social skills instruction, (b) mediated self‐management, and (c) a reinforcement system, was implemented to modify the socially withdrawn behavior of 3 elementary students. The effects of this treatment package were evaluated on the school playground—during recess—by recording both the number of communicative acts and the total time spent engaged in appropriate peer play for each target student. All target students showed marked improvement in their playground, social interaction. Future research should be conducted with similar populations, using variations of the described methods in other school settings. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 779–794, 2007.
School‐based support for GLBT students: A review of three levels of research
Authors: Hansen Anastasia L. 
Published: October 2007

AbstractGay, lesbian, bisexual, and transgender (GLBT) students experience harassment, alienation, and violence in schools. Several school‐based interventions have been suggested to provide a safe and effective learning environment for these students, but few have been evaluated or investigated experimentally. This review utilizes A.K. Ellis' (2001) model to review the research on school‐based interventions for GLBT youth at the levels of theory, applied investigation, and widespread implementation. Results suggest that, although the research base for psychological needs of GLBT youth is well established, applied investigation of small‐ and large‐scale implementation is in the early stages. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 839–848, 2007.
International Symposium on High Performance Proteomics 2007: A contribution to Proteomics May 14–16, 2007 Dortmund, Germany
Authors: Hamacher Michael , Grünewald Petra , Rammert Klaus , Bustamante Nadine Palacios , Hardt Tanja , van Hall André , Meyer Helmut E. 
Published: October 2007

AbstractThe symposium High Performance Proteomics was held in Dortmund on May 14‐16, 2007, to celebrate the opening of the Zentrum für Angewandte Proteomik as well as the 6th anniversary of the German Human Brain Proteome Project. It offered an outstanding opportunity to obtain a broad overview about all fields of proteomics and related fields, combining the expertise of biochemists, physicians, bioinformatics, mathematicians and other researchers in Life Sciences. The main topics were the presentation of state‐of‐the‐art proteomics technologies as well as possible transfer models for industrial applications. An accompanying industrial exhibition, as well as a discussion panel, offered the possibility to get in contact with colleagues and potential industrial partners. A visit to the former colliery Zeche Zollern and the social event at the Harenberg City‐Center with an excellent view around Dortmund also left time for further communication between the more than 200 attendees.
Preparation of poly(styrene‐b‐N‐isopropylacrylamide) micelles surface‐linked with gold nanoparticles and thermo‐responsive ultraviolet–visible absorbance
Authors: Li Jian , He Wei‐Dong , Sun Xiao‐Li 
Published: October 2007

AbstractPoly(styrene‐b‐N‐isopropylacrylamide) (PSt‐b‐PNIPAM) with dithiobenzoate terminal group was synthesized by reversible addition‐fragmentation‐transfer polymerization. The dithiobenzoate terminal group was converted into thiol terminal group with NaBH4, resulting thiol‐terminated PSt‐b‐PNIPAM‐SH. After PSt‐b‐PNIPAM‐SH assembled into core‐shell micelles in aqueous solution, gold nanoparticles were in situ surface‐linked onto the micelles through the reduction of gold precursor anions with NaBH4. Thus, temperature responsive core/shell micelles of PSt‐b‐PNIPAM surface‐linked with gold nanoparticles (PSt‐b‐PNIPAM‐Au micelles) were obtained. Transmission Electron Microscopy revealed the successful linkage of gold nanoparticles and the dependence of the number of gold nanoparticles per micelle on the molar ratio of HAuCl4 to thiol group of PSt‐b‐PNIPAM. Dynamic Light Scattering analysis demonstrated thermo‐responsive behavior of PSt‐b‐PNIPAM‐Au micelles. Changing the temperature of PSt‐b‐PNIPAM‐Au micelles led to the shrinkage of PNIPAM shell and allowed to tune the distance between gold nanoparticles. Ultraviolet–visible (UV–vis) spectroscopy clearly showed the reversible modulation of UV–vis absorbance of PSt‐b‐PNIPAM‐Au micelles upon heating and cooling. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5156–5163, 2007
Synthesis and characterization of a biodegradable amphiphilic copolymer based on branched poly(ϵ‐caprolactone) and poly(ethylene glycol)
Authors: Zou Tao , Li Song‐Lin , Zhang Xian‐Zheng , Wu Xiao‐Jun , Cheng Si‐Xue , Zhuo Ren‐Xi 
Published: October 2007

AbstractA novel biodegradable amphiphilic copolymer with hydrophobic poly(ε‐caprolactone) branches containing cholic acid moiety and a hydrophilic poly(ethylene glycol) chain was synthesized. The copolymer was characterized by FTIR, 1H NMR, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), polarizing light microscopy (PLM), and wide‐angle X‐ray diffraction (WAXD) analysis. The amphiphilic copolymer could self‐assemble into micelles in an aqueous solution. The critical micelle concentration of the amphiphilic copolymer was determined by fluorescence spectroscopy. A nanoparticle drug delivery system with a regularly spherical shape was prepared with high encapsulation efficiency. The in vitro drug release from the drug‐loaded polymeric nanoparticles was investigated. Because of the branched structure of the hydrophobic part of the copolymer and the relatively fast degradation rate of the copolymer, an improved release behavior was observed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5256–5265, 2007
Synthesis and characterization of hyperbranched polyfluorenes containing triarylpyrazoline cores towards efficient blue light‐emitting diodes
Authors: Peng Qiang , Yan Liushui , Chen Dezhi , Wang Fuzhi , Wang Ping , Zou Dechun 
Published: October 2007

AbstractNew series of hyperbranched polyfluorenes containing triarylpyrazoline cores, PFZ10, PFZ20, PFNZ10, and PFNZ20, have been synthesized according to the “A2 + A′2 + B3” Suzuki coupling method. The structures and property of the monomers and conjugated polymers were characterized by elemental analysis, gel permeation chromatography, cyclic voltammetry, thermogravimetric analysis, differential scanning calorimetry, and UV–visible absorption, 1H NMR, 13C NMR, and photoluminescence spectroscopies. All these polymers exhibited good solubility in common organic solvents and good thermal stability. The long‐wavelength emission of polyfluorenes had been effectively reduced in these hyperbranched polymers. Standard polymer light emitting devices (PLEDs) from PFZ10, PFZ20, PFNZ10, and PFNZ20, with the configuration of ITO/PEDOT/polymer/TPBI/Alq3/Mg:Ag, exhibited good electroluminescence (EL) properties The PLED based on PFNZ10 emitted pure blue light with a low turn‐on voltage of 5.3 V and a high EL efficiency of about 1.93%. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5296–5307, 2007
Synthesis and structural characterization of syndiotactic trans‐1,2 and cis‐1,2 polyhexadienes
Authors: Ricci Giovanni , Boglia Aldo , Motta Tiziano , Bertini Fabio , Boccia Antonella Caterina , Zetta Lucia , Alberti Enrica , Famulari Antonino , Arosio Paolo , Meille Stefano Valdo 
Published: October 2007

AbstractThe (E) isomer in mixtures of (E) and (Z) 1,3‐hexadiene was polymerized with the system CoCl2(PiPrPh2)2‐MAO, a highly active and stereospecific catalyst for the preparation of 1,2 syndiotactic polybutadiene. A new crystalline polymer with a melting point of 109 °C was obtained. The polymer was characterized by IR, NMR (13C, 1H in solution and 13C in the solid‐state), X‐ray diffraction, DSC, GPC and it was found to have a trans‐1,2 syndiotactic structure with a 5.18 ± 0.04 Å fiber periodicity. Since only the (E) isomer was polymerized, at the end of the reaction we were able to separate the (Z) isomer, which was ultimately polymerized with CpTiCl3‐MAO at low temperature, obtaining a low molecular weight, stereoregular polymer that, characterized by IR and NMR methods, was found to exhibit a cis‐1,2 syndiotactic structure, never reported before. Molecular mechanics calculations were carried out on the trans‐1,2 syndiotactic polymer and structural models consistent with the X‐ray diffraction data are proposed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5339–5353, 2007
Classifying protein kinase structures guides use of ligand‐selectivity profiles to predict inactive conformations: Structure of lck/imatinib complex
Authors: Jacobs Marc D. , Caron Paul R. , Hare Brian J. 
Published: October 2007

AbstractWe report a clustering of public human protein kinase structures based on the conformations of two structural elements, the activation segment and the C‐helix, revealing three discrete clusters. One cluster includes kinases in catalytically active conformations. Each of the other clusters contains a distinct inactive conformation. Typically, kinases adopt at most one of the inactive conformations in available X‐ray structures, implying that one of the conformations is preferred for many kinases. The classification is consistent with selectivity profiles of several well‐characterized kinase inhibitors. We show further that inhibitor selectivity profiles guide kinase classification. For example, selective inhibition of lck among src‐family kinases by imatinib (Gleevec) suggests that the relative stabilities of inactive conformations of lck are different from other src‐family kinases. We report the X‐ray structure of the lck/imatinib complex, confirming that the conformation adopted by lck is distinct from other structurally‐characterized src‐family kinases and instead resembles kinases abl1 and kit in complex with imatinib. Our classification creates new paths for designing small‐molecule inhibitors. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Assembly of the oncogenic DNA‐binding complex LMO2‐Ldb1‐TAL1‐E12
Authors: Ryan Daniel P. , Duncan Jaimee L. , Lee Christopher , Kuchel Philip W. , Matthews Jacqueline M. 
Published: October 2007

AbstractThe nuclear proteins TAL1 (T‐cell acute leukaemia protein 1) and LMO2 (LIM‐only protein 2) have critical roles in haematopoietic development, but are also often aberrantly activated in T‐cell acute lymphoblastic leukaemia. TAL1 and LMO2 operate within multifactorial protein–DNA complexes that regulate gene expression in the developing blood cell. TAL1 is a tissue‐specific basic helix–loop–helix (bHLH) protein that binds bHLH domains of ubiquitous E‐proteins, (E12 and E47), to bind E‐box (CANNTG) DNA motifs. TAL1bHLH also interacts specifically with the LIM domains of LMO2, which in turn bind Ldb1 (LIM‐domain binding protein 1). Here we used biophysical methods to characterize the assembly of a five‐component complex containing TAL1, LMO2, Ldb1, E12, and DNA. The bHLH domains of TAL1 and E12 alone primarily formed helical homodimers, but together preferentially formed heterodimers, to which LMO2 bound with high affinity (KA ∼ 108M−1). The resulting TAL1/E12/LMO2 complex formed in the presence or absence of DNA, but the different complexes preferentially bound different Ebox‐sequences. Our data provide biophysical evidence for a mechanism, by which LMO2 and TAL1 both regulate transcription in normal blood cell development, and synergistically disrupt E2A function in T‐cells to promote the onset of leukaemia. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Interaction cutoff effect on ruggedness of protein–protein energy landscape
Authors: Ruvinsky Anatoly M. , Vakser Ilya A. 
Published: October 2007

AbstractThe concept of the energy landscape is important for better understanding of protein–protein interactions and for designing adequate docking procedures. The intermolecular landscape has a rugged terrain that impedes search procedures. Its inherent ruggedness is related to the conformational characteristics of the molecules and to the form of the potential function—more rugged for short‐range potentials and less rugged for “soft,” typically long‐range potentials. Our study determined that the landscape ruggedness is further substantially exacerbated by truncation of the potentials. This additional ruggedness appears below certain critical interaction ranges that depend on the form of the potential. The theoretical model describing the cutoff effect on the landscape ruggedness is confirmed by the energy calculation on a dataset of protein–protein complexes. The negative effect of the potentials cutoff is well known. However, revealing its physical basis in terms of the energy landscape is important for better understanding of intermolecular interactions. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Automated prediction of ligand‐binding sites in proteins
Authors: Harris Rodney , Olson Arthur J. , Goodsell David S. 
Published: October 2007

AbstractWe present a method, termed AutoLigand, for the prediction of ligand‐binding sites in proteins of known structure. The method searches the space surrounding the protein and finds the contiguous envelope with the specified volume of atoms, which has the largest possible interaction energy with the protein. It uses a full atomic representation, with atom types for carbon, hydrogen, oxygen, nitrogen and sulfur (and others, if desired), and is designed to minimize the need for artificial geometry. Testing on a set of 187 diverse protein‐ligand complexes has shown that the method is successful in predicting the location and approximate volume of the binding site in 73% of cases. Additional testing was performed on a set of 96 protein‐ligand complexes with crystallographic structures of apo and holo forms, and AutoLigand was able to predict the binding site in 80% of the apo structures. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Tuning the shape of macroporous silicon
Authors: Trifonov T. , Garín M. , Rodríguez A. , Marsal L. F. , Alcubilla R. 
Published: October 2007

AbstractThe cover picture shows SEM images of the porous silicon membranes with controlled pore geometry which are subject to this issue's Editor's Choice article [1]. The authors demonstrate how the rounded‐square shape of pores in a silicon membrane prepared by photo‐electrochemical etching can be turned into a circular cross section using multiple oxidation/oxide‐stripping cycles.The image on the left is a side view onto a cleaved sample after eleven oxidation steps. The enlarged inset shows pore walls as thin as about 250 nm, including one set of the slightly thicker marks produced by reducing the current in order to obtain feedback on the etching rate. One oxidation step further, the membrane releases individual silicon pillars with a very large aspect ratio, as is illustrated by the top view on the right.The first author holds a post‐doctoral position at the Electronics Department of the Technical University of Catalonia, where his research focuses on the fabrication of 2D and 3D photonic crystals based on macroporous silicon.Also featured on the cover is a Review Article by Chivukula et al., surveying the various types of acoustic‐wave devices utilizing surface‐acoustic, acousto‐optic and photo‐acoustic effects for applications in biology and medicine [2]. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The effect of SWCNT and nano‐diamond films on human osteoblast cells
Authors: Kalbacova M. , Kalbac M. , Dunsch L. , Kromka A. , Vaněček M. , Rezek B. , Hempel U. , Kmoch S. 
Published: October 2007

AbstractHuman osteoblasts (SAOS‐2) are cultured on single‐walled carbon nanotube (SWCNT) and nanocrystalline diamond (NCD) films in order to evaluate their potential for biological application. We present dependence of metabolic activity and morphology of osteoblasts on (i) material substrate (NCD or SWCNT films), (ii) surface termination – O‐termination causing hydrophilic surface and H‐termination (as deposited NCDs) causing hydrophobic surface, (iii) surface roughness in the range of 11–39 nm RMS and (iv) SWCNT production technique – laser ablation, arc‐discharge and HiPco. The metabolic activity decreases to the same non‐toxic level on SWCNT films produced by different techniques as well as on H‐terminated NCD compared to tissue culture polystyrene. The metabolic activity is increasing on O‐terminated NCD films as a function of their roughness. Morphological observations support superior properties of O‐terminated NCD films. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)