bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gold Nanoparticle Cored Polyferrocenyl Dendrimers: Modes of Synthesis and Functions as Exoreceptors of Biologically Important Anions and Reusable Redox Sensors
Authors: Daniel Marie‐Christine , Aranzaes Jaime Ruiz , Nlate Sylvain , Astruc Didier 
Published: May 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Alkali Metal Phenylphosphandiides: [M2PnPhn] (M: Li, Na)
Authors: Stein Daniel , Geier Jens , Schoenberg Hartmut , Gruetzmacher Hansjoerg 
Published: May 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Coordination Chemistry of Pyridyl Oximes
Authors: Milios Constantinos J. , Stamatatos Theocharis C. , Perlepes Spyros P. 
Published: May 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Thyrotropin‐Releasing Hormone (TRH)— Peptide Synthesis on a Fluorous Support
Authors: Mizuno Mamoru , Goto Kohtaro , Miura Tsuyoshi , Inazu Toshiyuki 
Published: May 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Alkylperoxy Sulfonic Acids: Thermal Stability and Oxidizing Properties
Authors: Safiullin R. L. , Zaripov R. N. , Enikeeva L. R. 
Published: May 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Diagnostic and extent of disease multigene assay for malignant thyroid neoplasms
Authors: Kebebew Electron , Peng Miao , Reiff Emily , McMillan Alex 
Published: May 2006

AbstractBACKGROUNDApproximately 30% of fine‐needle aspiration (FNA) biopsies of thyroid nodules are indeterminate, nondiagnostic, or suspicious. The purpose of the current study was to determine the accuracy of novel candidate diagnostic markers to distinguish benign from malignant thyroid neoplasms, and to predict the extent of disease.METHODSA real‐time quantitative reverse‐transcriptase polymerase chain reaction (RT‐PCR) assay of 6 novel candidate diagnostic and extent of disease marker genes (extracellular matrix protein 1 [ECM1]; transmembrane protease, serine 4 [TMPRSS4]; angiopoietin 2 [ANGPT2]; TIMP metallopeptidase inhibitor 1 [TIMP1]; ephrin‐B2 [EFNB2], and epidermal growth factor receptor [EGFR]) was used in 126 thyroid tissues. To evaluate the performance of the scoring model for the diagnostic markers in combination, the area under the receiver operating characteristic (ROC) curve (AUC) was determined.RESULTSThe levels of ECM1, TMPRSS4, ANGPT2, and TIMP1 mRNA expression were found to be independent diagnostic markers of malignant thyroid neoplasms. The AUC for the 4 diagnostic genes in combination was 0.993 with a sensitivity of 100%, a specificity of 94.6%, a positive predictive value of 96.5%, and a negative predictive value of 100%. In 31 thyroid nodule FNA biopsy samples, the scoring model had a sensitivity of 91.0%, a specificity of 95.0%, a positive predictive value of 92.9%, and a negative predictive value of 92.3%. The multigene assay correctly classified 93% of tumors into the correct risk group (low‐risk vs. high‐risk) with a sensitivity of 78.9% (true positive in high‐risk tumors), specificity of 92% (true negative in low‐risk tumors), positive predictive value of 87.5%, and negative predictive value of 92%. In 11 malignant thyroid nodule FNA samples, the extent of disease scoring model correctly identified 3 of 4 high‐risk differentiated thyroid cancers and 7 of 7 low‐risk differentiated thyroid cancers.CONCLUSIONSThis novel multigene assay is an excellent diagnostic and extent of disease marker for differentiated thyroid cancer and would be a helpful adjunct to FNA biopsy of thyroid nodules. Cancer 2006. © 2006 American Cancer Society.
Low‐Temperature EPR and Mössbauer Spectroscopy of Two Cytochromes with His–Met Axial Coordination Exhibiting HALS Signals
Authors: Zoppellaro Giorgio , Teschner Thomas , Harbitz Espen , Schünemann Volker , Karlsen Solveig , Arciero David M. , Ciurli Stefano , Trautwein Alfred X. , Hooper Alan B. , Andersson K. Kristoffer 
Published: May 2006

AbstractC‐type cytochromes with histidine–methionine (His–Met) iron coordination play important roles in electron‐transfer reactions and in enzymes. Low‐temperature electron paramagnetic resonance (EPR) spectra of low‐spin ferric cytochromes c can be divided into two groups, depending on the spread of g values: the normal rhombic ones with small g anisotropy and gmax below 3.2, and those featuring large g anisotropy with gmax between 3.3 and 3.8, also denoted as highly axial low spin (HALS) species. Herein we present the detailed magnetic properties of cytochrome c553 from Bacillus pasteurii (gmax 3.36) and cytochrome c552 from Nitrosomonas europaea (gmax 3.34) over the pH range 6.2 to 8.2. Besides being structurally very similar, cytochrome c553 shows the presence of a minor rhombic species at pH 6.2 (6 %), whereas cytochrome c552 has about 25 % rhombic species over pH 7.5. The detailed Mössbauer analysis of cytochrome c552 confirms the presence of these two low‐spin ferric species (HALS and rhombic) together with an 8 % ferrous form with parameters comparable to the horse cytochrome c. Both EPR and Mössbauer data of axial cytochromes c with His–Met iron coordination are consistent with an electronic (dxy)2 (dxz)2 (dyz)1 ground state, which is typical for Type I model hemes.
Auditory temporal processing deficits in children with reading disabilities
Authors: Cohen‐Mimran Ravit , Sapir Shimon 
Published: May 2006

AbstractThe role of central auditory processing in reading skill development and reading disorders is unclear. The purpose of this study was to examine whether individuals with specific reading disabilities (SRD) have deficits in processing rapidly presented, serially ordered non‐speech auditory signals. To this end, we compared 12 children with SRD and 12 children without SRD on their ability to detect differences and similarities in pure tones of 1000 and 2000 Hz when these signals were presented in pairs (same or different tones, randomly ordered) with short (50 ms) versus long (500 ms) inter stimulous intervals (ISI). Results showed that the children with SRD had significant difficulty in discriminating between pure tones with short, but not long ISI, whereas the controls performed well with both short and long ISI. The two groups did not differ significantly on measures of attention (d2) and performance IQ, and there were no significant correlations between these measures and ISI performance. There were significant correlations between the short ISI performance and phonologic awareness test results when the two groups were combined. These findings support the specific rapid auditory processing deficit hypothesis of SRD. Examination of intra‐subject variability in performance indicated that children from the SRD group showed both decrement in performance with time on task and high overall variability in performance as compared to the controls. These findings underpin the importance of using time‐series analyses of performance. Copyright © 2006 John Wiley & Sons, Ltd.
Systematic Studies on Photoluminescence of Oligo(arylene‐ethynylene)s: Tunability of Excited States and Derivatization as Luminescent Labeling Probes for Proteins
Authors: Zhi Yong‐Gang , Lai Siu‐Wai , Chan Queenie K.‐W. , Law Yuen‐Chi , Tong Glenna S.‐M. , Che Chi‐Ming 
Published: May 2006

AbstractFunctionalized oligo(phenylene‐ethynylene)s (OPEs) with different conjugation lengths, p‐X(C6H4C≡C)nSiMe3 (n = 1–4; X = NH2, NMe2, H) were synthesized by Sonogashira coupling of (phenylene‐ethynylene)s and 1‐iodo‐4‐(trimethylsilylethynyl)benzene, followed by desilylation of the p‐substituted (trimethylsilylethynyl)benzenes with potassium hydroxide. The photoluminescent properties for the OPE series with different chain lengths and their solvatochromic responses were examined. The absorption maxima were red‐shifted with increasing numbers of –(C6H4C≡C)– units (n), and a linear plot of the absorption energy maxima vs. 1/n was obtained for each series. The emission spectra in dichloromethane showed a broad and structureless band, the energies of which (in wavenumbers) also fit linearly with 1/n. Both the absorption and emission wavelength maxima of the NH2‐ and NMe2‐substituted OPEs exhibited significant solvent dependence, whereas the parent OPEs (X = H) showed only minor shifts of the λmax values in different solvents. Substituent effects upon the photoluminescent characteristics of the OPEs and the tunability of the excited states were examined with the p‐X(C6H4C≡C)nSiMe3 (n = 2, 3; X = NH2, NMe2, H, SMe, OMe, OH, and F) series. The H‐ and F‐substituted counterparts exhibited high‐energy vibronically structured emissions attributed to the 3(ππ*) excited states of the (arylene‐ethynylene) backbone. For compounds bearing NH2 and NMe2 groups, a broad red‐shifted emission with a remarkable Stokes shift from the respective absorption maximum was observed, which can be assigned to an n → π* transition. The n → π* assignment was supported by MO calculations on the model compounds p‐X(C6H4C≡C)2SiH3 (X = NH2, H). Functionalization of the oligo(arylene‐ethynylene)s with the N‐hydroxysuccinimidyl (NHS) moiety enabled covalent attachment of the fluorophore to HSA protein molecules. A series of fluorescent labels, namely p‐X(C6H4C≡C)nC6H4NHS, (n = 1, X = NH2, NMe2, SMe, OMe, OH, F; n = 2, X = NH2, NMe2) and p‐Me2NC6H4C≡C(C4H2S)C≡CC6H4NHS were synthesized, and their conjugates with HSA (human serum albumin) were characterized by MALDI‐TOF mass spectrometry, UV/Vis absorption spectroscopy, and gel electrophoresis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Karhunen–Loeve representations of turbulent channel flows using the method of snapshots
Authors: Handler R. A. , Housiadas K. D. , Beris A. N. 
Published: May 2006

AbstractFor three‐dimensional flows with one inhomogeneous spatial coordinate and two periodic directions, the Karhunen–Loeve procedure is typically formulated as a spatial eigenvalue problem. This is normally referred to as the direct method (DM). Here we derive an equivalent formulation in which the eigenvalue problem is formulated in the temporal coordinate. It is shown that this so‐called method of snapshots (MOS) has some numerical advantages when compared to the DM. In particular, the MOS can be formulated purely as a matrix composed of scalars, thus avoiding the need to construct a matrix of matrices as in the DM. In addition, the MOS avoids the need for so‐called weight functions, which emerge in the DM as a result of the non‐uniform grid typically employed in the inhomogeneous direction. The avoidance of such weight functions, which may exhibit singular behaviour, guarantees satisfaction of the boundary conditions. The MOS is applied to data sets recently obtained from the direct simulation of turbulence in a channel in which viscoelasticity is imparted to the fluid using a Giesekus model. The analysis reveals a steep drop in the dimensionality of the turbulence as viscoelasticity is increased. This is consistent with the results that have been obtained with other viscoelastic models, thus revealing an essential generic feature of polymer‐induced drag reduced turbulent flows. Published in 2006 by John Wiley & Sons, Ltd.
Pancreatic adenocarcinoma—Genetic portrait from chromosomes to microarrays
Authors: Karhu Ritva , Mahlamäki Eija , Kallioniemi Anne 
Published: May 2006

AbstractPancreatic adenocarcinoma is the fifth leading cause of cancer death with a 5‐year survival rate of less than 5%. Although the role of a few known oncogenes and tumor suppressor genes in the development of pancreatic cancer is fairly well established, it is obvious that the majority of genetic changes responsible for the initiation and progression of this disease are still unknown. In this review, the authors will discuss the results from various genome‐wide screening efforts, from traditional chromosome analyses to modern DNA microarray studies, which have provided an enormous amount of information on genetic alterations in pancreatic adenocarcinoma. Exciting findings have emerged from these studies, highlighting multiple potential chromosomal regions that may harbor novel cancer genes involved in the molecular pathogenesis of this lethal disorder. These findings complete the picture of pancreatic adenocarcinoma as a genetically highly complex and heterogenous tumor type with an ongoing instability process. In addition, the precisely localized copy number changes offer a valuable starting point for further studies required to identify the genes involved and to characterize their potential functional role in the development and progression of pancreatic adenocarcinoma. © 2006 Wiley‐Liss, Inc.
Role of all‐trans retinoic acid in neurite outgrowth and axonal elongation
Authors: Clagett‐Dame Margaret , McNeill Elizabeth M. , Muley Parag D. 
Published: May 2006

AbstractThe vitamin A metabolite, all‐trans retinoic acid (atRA) plays essential roles in nervous system development, including neuronal patterning, survival, and neurite outgrowth. Our understanding of how the vitamin A acid functions in neurite outgrowth comes largely from cultured embryonic neurons and model neuronal cell systems including human neuroblastoma cells. Specifically, atRA has been shown to increase neurite outgrowth from embryonic DRG, sympathetic, spinal cord, and olfactory receptor neurons, as well as dissociated cerebra and retina explants. A role for atRA in axonal elongation is also supported by a limited number of studies in vivo, in which a deficiency in retinoid signaling produced either by dietary or genetic means has been shown to alter neurite outgrowth from the spinal cord and hindbrain regions. Human neuroblastoma cells also show enhanced numbers of neurites and longer processes in response to atRA. The mechanism whereby retinoids regulate neurite outgrowth includes, but is not limited to, the regulation of the transcription of neurotrophin receptors. More recent evidence supports a role for atRA in regulating components of other signaling pathways or candidate neurite‐regulating factors. Some of these effects, such as that on neuron navigator 2 (NAV2), may be direct, whereas others may be secondary to other atRA‐induced changes in the cell. This review focuses on what is currently known about neurite initiation and growth, with emphasis on the manner in which atRA may influence these events. © 2006 Wiley Periodicals, Inc. J Neurobiol 66: 739–756, 2006
Ligand‐induced dynamical regulation of NO conversion in Mycobacterium tuberculosis truncated hemoglobin‐N
Authors: Bidon‐Chanal Axel , Martí Marcelo A. , Crespo Alejandro , Milani Mario , Orozco Modesto , Bolognesi Martino , Luque F. Javier , Estrin Darío A. 
Published: May 2006

AbstractMycobacterium tuberculosis, the causative agent of human tuberculosis, is forced into latency by nitric oxide produced by macrophages during infection. In response to nitrosative stress M. tuberculosis has evolved a defense mechanism that relies on the oxygenated form of “truncated hemoglobin” N (trHbN), formally acting as NO‐dioxygenase, yielding the harmless nitrate ion. X‐ray crystal structures have shown that trHbN hosts a two‐branched protein matrix tunnel system, proposed to control diatomic ligand migration to the heme, as the rate‐limiting step in NO conversion to nitrate. Extended molecular dynamics simulations (0.1 μs), employed here to characterize the factors controlling diatomic ligand diffusion through the apolar tunnel system, suggest that O2 migration in deoxy‐trHbN is restricted to a short branch of the tunnel, and that O2 binding to the heme drives conformational and dynamical fluctuations promoting NO migration through the long tunnel branch. The simulation results suggest that trHbN has evolved a dual‐path mechanism for migration of O2 and NO to the heme, to achieve the most efficient NO detoxification. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Variation of thermal resistance with input power in LEDs
Authors: Yang Lianqiao , Hu Jianzheng , Kim Lan , Shin Moo Whan 
Published: May 2006

AbstractIn this paper we report on the thermal analysis of high‐power light‐emitting diodes (LEDs) as a function of input power. The transient thermal measurement method using structure function was employed to investigate the thermal behavior of LEDs at different working conditions. It was shown that a 5 W LED package installed with four chips exhibited an increase of thermal resistance from 7.06 K/W to 8.83 K/W with the input current ranging from 50 mA to 700 mA at the ambient temperature of 25 °C. However, the thermal resistance for a 1 W LED package with one chip was decreased from 20.33 K/W to 19.54 K/W with the input current ranging from 50 mA to 350 mA. Based on our improved LED model, the different trends for the two packages are attributed to the difference in the power dissipated by internal series electrical resistances. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Root respiration in temperate mountain grasslands differing in land use
Authors: BAHN MICHAEL , KNAPP MARGIT , GARAJOVA ZOFIA , PFAHRINGER NADINE , CERNUSCA ALEXANDER 
Published: May 2006

AbstractIn grasslands the proportionally largest emission of CO2 comes from the soil. This study aimed to assess how root respiration, a major flux component, is affected by land management and changes in land use. Respiration of roots, separated to classes of different diameter, was measured in 11 temperate mountain grasslands, including meadows, pastures and abandoned sites at three geographic locations. Specific root respiration was affected by nitrogen (N) concentration, root class and land use. The relationship between root N concentration and respiration differed between locations. With increasing root diameter there was a decrease in root respiration, N concentration, respiration per unit N and Q10. In grasslands abandoned for several years specific root respiration was lower than in meadows, pastures and a recently abandoned site. This was due to lower root N concentrations and/or lower respiration rates per unit N within each root class. Since root biomass was higher on abandoned grasslands, total ecosystem root respiration did not differ consistently between sites. Ecosystem root respiration showed distinct seasonal changes due to changes in root biomass, which were less pronounced on abandoned grasslands. Fine roots generally made up the largest portion of ecosystem root respiration, their contribution varying between 35% and 96%. On meadows, clipping increased soil and root respiration by increasing soil temperature. When corrected for temperature effects soil respiration was reduced by 20–50%, whilst root respiration was little affected, suggesting that carbohydrate reserves sustained root metabolism for several days and that microbial respiration strongly responded to short‐term changes in assimilate supply.
Temperature and biomass influences on interannual changes in CO2 exchange in an alpine meadow on the Qinghai‐Tibetan Plateau
Authors: KATO TOMOMICHI , TANG YANHONG , GU SONG , HIROTA MITSURU , DU MINGYUAN , LI YINGNIAN , ZHAO XINQUAN 
Published: May 2006

AbstractThree years of eddy covariance measurements were used to characterize the seasonal and interannual variability of the CO2 fluxes above an alpine meadow (3250 m a.s.l.) on the Qinghai‐Tibetan Plateau, China. This alpine meadow was a weak sink for atmospheric CO2, with a net ecosystem production (NEP) of 78.5, 91.7, and 192.5 g C m−2 yr−1 in 2002, 2003, and 2004, respectively. The prominent, high NEP in 2004 resulted from the combination of high gross primary production (GPP) and low ecosystem respiration (Re) during the growing season. The period of net absorption of CO2 in 2004, 179 days, was 10 days longer than that in 2002 and 5 days longer than that in 2003. Moreover, the date on which the mean air temperature first exceeded 5.0°C was 10 days earlier in 2004 (DOY110) than in 2002 or 2003. This date agrees well with that on which the green aboveground biomass (Green AGB) started to increase. The relationship between light‐use efficiency and Green AGB was similar among the three years. In 2002, however, earlier senescence possibly caused low autumn GPP, and thus the annual NEP, to be lower. The low summertime Re in 2004 was apparently caused by lower soil temperatures and the relatively lower temperature dependence of Re in comparison with the other years. These results suggest that (1) the Qinghai‐Tibetan Plateau plays a potentially significant role in global carbon sequestration, because alpine meadow covers about one‐third of this vast plateau, and (2) the annual NEP in the alpine meadow was comprehensively controlled by the temperature environment, including its effect on biomass growth.
Flexible responses of insects to changing environmental temperature – early season development of Craspedolepta species on fireweed
Authors: HODKINSON IAN D. , BIRD JEREMY M. 
Published: May 2006

AbstractDevelopmental response to temperature during the critical early season growing period was investigated in two congeneric species of Craspedolepta feeding on Epilobium angustifolium at three sites at different altitudes in Norway and the UK. The larval development reaction norm to temperature, measured as accumulated day degrees, was not significantly different between Craspedolepta nebulosa and Craspedolepta subpunctata at sites where they co‐occurred but C. nebulosa development was consistently more advanced at any site. For individual species the reaction norms at the lowest site (Ainsdale, UK) were similar to the intermediate site (Geilo, Norway): and there were no differences between years. Insect size remained relatively constant. However, at the highest site (Haugastøl, Norway), where C. subpunctata is unable to complete its development, the reaction norm for C. nebulosa was significantly higher than at Geilo and the individual insects produced were smaller. These adaptations allow life‐history completion under limiting temperature conditions. An experiment at Ainsdale, to raise the mean temperature by around 2.5°C during the early growing season, resulted in accelerated development in both C. nebulosa and C. subpunctata but development in C. nebulosa was accelerated proportionately more. C. nebulosa thus displays the greater plasticity in developmental response to environmental temperature that allows it to occupy a greater altitudinal and latitudinal range than C. subpunctata, in which the response is less plastic and more canalized. The likely individualistic responses of the two species to climate warming are considered.