bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interpretation of capacitance spectra and transit times of single carrier space‐charge limited transport in organic layers with field‐dependent mobility
Authors: Montero José M. , Bisquert Juan , Garcia‐Belmonte Germà , Bolink Henk J. , Barea Eva M. 
Published: May 2007

AbstractThe ac impedance characteristics of a single carrier with space‐charge limited current (SCLC) transport in organic layers with field‐dependent mobility is analyzed, indicating the similarities as well as the differences to the constant mobility case. The model provides capacitance spectra and transit times from different calculation methods, in relation to the electric field distribution in the SCLC regime. It is found that the low frequency capacitance lies in the range 3Cg/4 < Cif < Cg, with respect to the geometric capacitance Cg. An approximated expression for the variation of the transit time with applied bias is derived, in good agreement with exact calculations. Experimental results of capacitance spectra of hole‐only PPV devices indicate the validity of the SCLC model but also show a strong contribution of trapping at low frequencies that overlap the low‐frequency value of the SCLC capacitance. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Extrinsic and intrinsic origins of anisotropic magnetoresistance in doped YIG
Authors: Lehmann‐Szweykowska A. , Wojciechowski R. J. , Gehring G. A. , Szamer A. , Wigen P. E. , Micnas R. 
Published: May 2007

AbstractA microscopic model of Ca:YIG minimal system in the form of a pair of the tetrahedral (d) iron–oxygen clusters, separated by the octahedral (a) cluster, coupled in series to the electrodes, is employed in an interpretation of the experimentally observed intriguing behaviour of anisotropic magnetoresistance (MR). Two possible origins of the anisotropy of MR are viewed. The extrinsic one results from orbital contributions to magnetic moments of the central clusters and reveals itself in the external magnetic field. The intrinsic one is caused by different spin polarisation of the left and the right d clusters with respect to the middle a cluster. The effect is connected with a presence of a compensating hole at one of the tetrahedral clusters. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Partial localization of correlated electrons in an orbitally degenerate narrow band: spin dependent masses, saturated ferromagnetism
Authors: Jędrak Jakub , Spałek Jozef , Zwicknagl Gertrud 
Published: May 2007

AbstractWe have determined the localization threshold in a partially filled and doubly degenerate model of correlated electrons. Particular emphasis is put on a non‐integer band filling n ≥ 1, when the system decomposes into the localized and the itinerant subsystems. A simultaneous transition to the ferromagnetic state is discussed as driven by the Hund's rule coupling combined with the effective field coming from the correlations. Dependence of the quasiparticle mass on the spin direction appears naturally in the spin‐polarized phase and is attributed to the electron correlation effects, as is also a metamagnetic transition in an applied field. Although the main results have been obtained within the saddle point slave‐boson approach, their qualitative features are discussed in general terms, i.e. as a transition from quantum‐mechanical indistinguishability of particles forming the Fermi fluid to a two‐component situation. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Raman spectroscopy of pentyl‐functionalized carbon nanotubes
Authors: Müller M. , Maultzsch J. , Wunderlich D. , Hirsch A. , Thomsen C. 
Published: May 2007

AbstractWe present Raman scattering on carbon nanotubes functionalized with pentyl groups. Studies of the intermediate frequency region and the C–H bond stretching signal along with the D mode show evidence of the addition reaction by Raman spectroscopy. From the resonance profiles of the radial breathing mode (RBM) we assign the chiral indices of the tubes and study the influence of the functionalization on the transition energies, shift and intensity of the RBM signal. The largest effect we observe is on the Raman intensity of the radial breathing mode. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)magnified imagePentyl–SWNT
Nanoporous Aluminum Oxide Membranes for Filtration and Biofunctionalization
Authors: Thormann Annika , Teuscher Nico , Pfannmöller Monika , Rothe Ulrich , Heilmann Andreas 
Published: May 2007

AbstractNanoporous aluminum oxide membranes with high open porosity are prepared by anodic oxidation. Conventional self‐supporting as well as mechanically stabilized nanoporous membranes are produced from aluminum plates and microimprinted aluminum foils, respectively. The mechanically stabilized membranes are characterized by very thin membrane parts stabilized by surrounding thick bridges. The minimal thickness of these thin membranes with open pores on both sides is 1 μm, with a mean pore size of the parallel open pores of 185 nm. With these two kinds of membrane the flow rates for cross filtration can be tuned over a wide range. With the mechanically stabilized membranes, substantially higher flow rates are achieved and experiments that cannot be performed with thicker membranes become possible. The biofunctionalization of the pore walls with archaebacterial tetraether lipids is realized and proved using aminated semiconductor nanocrystals. The lipid layer deposited on the pore walls also changes the filtration properties.
Cluster‐based information processing in wireless sensor networks: an energy‐aware approach
Authors: Tian Yuan , Ekici Eylem , Özgüner Füsun 
Published: May 2007

AbstractEmerging Wireless Sensor Network (WSN) applications demand considerable computation capacity for in‐network processing in resource limited WSN environments. To achieve the required processing capacity under energy consumption constraints, collaboration among sensors through parallel processing methods emerges as a promising solution. Although such methods have been extensively studied in wired networks of processors, its counterpart for WSNs remains largely unexplored. In this paper, a localized task mapping and scheduling solution for energy‐constrained applications in WSNs, Energy‐constrained Task Mapping and Scheduling (EcoMapS), is presented. EcoMapS guarantees energy consumption constraints while minimizing schedule length. EcoMapS incorporates channel modeling, concurrent task mapping, communication and computation scheduling, and sensor failure handling algorithms. Simulation results show significant performance improvements of EcoMapS over existing mechanisms in terms of minimizing schedule lengths subject to energy consumption constrains. Copyright © 2007 John Wiley & Sons, Ltd.
Generalization of signcryption for resources‐constrained environments
Authors: Han Yiliang 
Published: May 2007

AbstractTraditional signcryption is not feasible for some information security scenarios, though it is a new cryptographic primitive that simultaneously fulfills both the functions of signature and encryption.Generalized signcryptionis an adaptive primitive which achieves both secrecy and authenticity or provides them respectively by a generic structure. The notions related to generalized signcryption such as syntax, correctness, and security are proposed in the paper. A practical generalized signcryption scheme ECGSC is evaluated carefully also. The formal proofs for the unforgeability and confidentiality of ECGSC in the Random Oracle model are provided. To give a solution for multiple user settings, an efficient multicast scheme is also designed. ECGSC will seamlessly switch to the Elliptic Curve Digital Signature Algorithm (ECDSA) or a provable secure asymmetric encryption scheme when recipient's keys or sender's keys are absent. Compared with other schemes, it saves 9–14% communication costs in the signcryption mode. It also saves 78–82% computational costs. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and Properties of Functionalized Alkylaldonamides
Authors: Piasecki Andrzej , Piłakowska‐Pietras Dorota 
Published: May 2007

AbstractApplication studies of novel saccharide‐type nonionic surfactants were performed. The homolog series of N‐alkyl‐N‐(2‐hydroxyethyl)gluconamides and N‐alkyl‐N‐(2‐hydroxyethyl)glucoheptonamides (alkyl: n‐C10H21, n‐C12H25, and n‐C14H29) were synthesized and their structures were confirmed by means of elemental analysis and 1H‐NMR spectroscopy. The investigations showed that the application of N‐alkyl‐N‐(2‐hydroxyethyl)aldonamides as surfactants in an aqueous media can be limited. This is because of their relatively high Krafft point temperature. However, some variants can be successfully applied in mixtures with an anionic surfactant: sodium salt of n‐dodecyl sulfate (SDS). The addition of SDS causes significant improvement of the Krafft point temperatures. In some cases a synergistic effect was observed, i.e., the Krafft point temperature of the binary mixture was lower that the corresponding values for the solutions containing individual compounds. It is also remarkable, that the aqueous solutions of binary surfactant mixtures were characterized by improved foaming properties, as compared to that of pure SDS.
Pelvic and para‐aortic lymphadenectomy in patients with endometrioid adenocarcinoma of the endometrium
Authors: Geisler J.P. , Linnemeier G.C. , Manahan K.J. 
Published: May 2007

AbstractBackground: The purpose is to determine the rate of lymph node metastases in women with endometrioid adenocarcinoma of the endometrium (EAE) undergoing systematic lymphadenectomy. Methods: Patients (349) underwent a complete pelvic and para‐aortic lymphadenectomy from caudal to the median circumflex to the level of the renal vessels. Results: Grade 1 tumors accounted for 32.7% of the tumors and 31.0% of the positive nodes, grade 2 accounted for 47.3% of the tumors (37.9% of positive nodes), and grade 3 accounted for 20.1% of the tumors and 31.0% of the positive nodes (P > 0.05). Positive nodes were found in 15.8% of grade 1 tumors, 13.3% of grade 2 tumors and 25.7% of grade 3 tumors (P > 0.05). Isolated para‐aortic involvement without pelvic nodal involvement occurred in 29% of patients with positive nodes. Conclusions: When complete lymphadenectomies are performed in EAE, positive lymph nodes (including isolated para‐aortic lymph nodes) are common in all grades.
Prognostic indices with brief and standard CBT for panic disorder: II. Moderators of outcome
Authors: DOW MICHAEL G. T. , KENARDY JUSTIN A. , JOHNSTON DEREK W. , NEWMAN MICHELLE G. , TAYLOR C. BARR , THOMSON AILEEN 
Published: May 2007

ABSTRACTBackgroundDespite the growth of reduced therapist-contact cognitive behavioural therapy (CBT) programmes, there have been few systematic attempts to determine prescriptive indicators for such programmes vis-à-vis more standard forms of CBT delivery. The present study aimed to address this in relation to brief (6-week) and standard (12-week) therapist-directed CBT for panic disorder (PD) with and without agoraphobia. Higher baseline levels of severity and associated disability/co-morbidity were hypothesized to moderate treatment effects, in favour of the 12-week programme.MethodAnalyses were based on outcome data from two out of three treatment groups (n=72) from a recent trial of three forms of CBT delivery for PD. The dependent variables were a continuous composite panic/anxiety score and a measure of clinical significance. Treatment×predictor interactions were examined using multiple and logistic regression analyses.ResultsAs hypothesized, higher baseline severity, disability or co-morbidity as indexed by strength of dysfunctional agoraphobic cognitions; duration of current episode of PD; self-ratings of panic severity; and the 36-item Short Form Health Survey (SF-36) (Mental component) score were all found to predict poorer outcome with brief CBT. A similar trend was apparent in relation to baseline level of depression. With high and low end-state functioning as the outcome measure, however, only the treatment×agoraphobic cognitions interaction was found to be significant.ConclusionsWhile there was no evidence that the above variables necessarily contraindicate the use of brief CBT, they were nevertheless associated with greater overall levels of post-treatment improvement with the 12-week approach.
Recovery in culture of viable but nonculturable Vibrio parahaemolyticus: regrowth or resuscitation?
Authors: Coutard François , Crassous Philippe , Droguet Mickaël , Gobin Eric , Colwell Rita R , Pommepuy Monique , Hervio-Heath Dominique 
Published: May 2007

Abstract
The objective of this study was to explore the recovery of culturability of viable but nonculturable (VBNC) Vibrio parahaemolyticus after temperature upshift and to determine whether regrowth or resuscitation occurred. A clinical strain of V. parahaemolyticus Vp5 was rendered VBNC by exposure to artificial seawater (ASW) at 4°C. Aliquots of the ASW suspension of cells (0.1, 1 and 10 ml) were subjected to increased temperatures of 20°C and 37°C. Culturability of the cells in the aliquots was monitored for colony formation on a rich medium and changes in morphology were measured by scanning (SEM) and transmission (TEM) electron microscopy. Samples of VBNC cells were fixed and examined by SEM, revealing a heterogeneous population comprising small cells and larger, flattened cells. Forty-eight hours after temperature upshift to 20°C or 37°C, both elongation and division by binary fission of the cells were observed, employing SEM and TEM, but only in the 10-ml aliquots. The results suggest that a portion of VBNC cells is able to undergo cell division. It is concluded that a portion of VBNC cells of V. parahaemolyticus subjected to cold temperatures remain viable. After temperature upshift, regrowth of those cells, rather than resuscitation of all bacteria of the initial inoculum, appears to be responsible for recovery of culturability of VBNC cells of V. parahaemolyticus. Nutrient in filtrates of VBNC cells is hypothesized to allow growth of the temperature-responsive cells, with cell division occurring via binary fission, but also including an atypical, asymmetric cell division.
Phylogeny of Branchiopoda (Crustacea) based on a combined analysis of morphological data and six molecular loci
Authors: Richter Stefan , Olesen Jørgen , Wheeler Ward C. 
Published: May 2007

AbstractThe phylogenetic relationships of branchiopod crustaceans have been in the focus of a number of recent morphological and molecular systematic studies. Although agreeing in some respects, major differences remain. We analyzed molecular sequences and morphological characters for 43 branchiopods and two outgroups. The branchiopod terminals comprise all eight “orders”. The molecular data include six loci: two nuclear ribosomal genes (18S rRNA, 28S rRNA), two mitochondrial ribosomal genes (12S rRNA, 16S rRNA), one nuclear protein coding gene (elongation factor 1α), and one mitochondrial protein coding gene (cytochrome c oxidase subunit I). A total of 65 morphological characters were analyzed dealing with different aspects of branchiopod morphology, including internal anatomy and larval characters. The morphological analysis resulted in a monophyletic Phyllopoda, with Notostraca as the sister group to the remaining taxa supporting the Diplostraca concept (“Conchostraca” + Cladocera). “Conchostraca” is not supported but Cyclestheria hislopi is the sister group to Cladocera (constituting together Cladoceromorpha) and Spinicaudata is closer to Cladoceromorpha than to Laevicaudata. Cladocera is supported as monophyletic. The combined analysis under equal weighting gave results in some respects similar to the morphological analysis. Within Phyllopoda, Cladocera, Cladoceromorpha and Spinicaudata + Cladoceromorpha are monophyletic. The combined analysis is different from the morphological analysis with respect to the position of Notostraca and Laevicaudata. Here, Laevicaudata is the sister group to the remaining Phyllopoda and Notostraca is sister group to Spinicaudata and Cladoceromorpha. A sensitivity analysis using 20 different parameter sets (different insertion–deletion [indel]/substitution and transversion/transition ratios) show the monophyly of Anostraca, Notostraca, Laevicaudata, Spinicaudata, Cladoceromorpha, Cladocera, and within Cladocera, of Onychopoda and Gymnomera under all or almost all (i.e., 19 of 20) parameter sets. Analyses with an indel‐to‐transversion ratio up to 2 result in monophyletic Phyllopoda, with Laevicaudata as sister group to the remaining Phyllopoda and with Spinicaudata and Cladoceromorpha as sister groups. Almost all analyses (including those with higher indel weights) result in the same topology when only ingroup taxa are considered.© The Willi Hennig Society 2007.
Naming taxa from cladograms: some confusions, misleading statements, and necessary clarifications
Authors: Dubois Alain 
Published: May 2007

Abstract Hillis (2006) recently published a rebuttal of my analysis (Dubois, 2006c) of a paper by Hillis and Wilcox (2005) on the taxonomy and nomenclature of American ranid frogs. His paper consists not only in a reply to my paper, as it contains in fact three distinct kinds of statements: (1) an attempt to “save” the new generic nomina proposed by Hillis and Wilcox (2005) from being considered nomina nuda under the Code; (2) another plea for the superiority of the Phylocode over the Code, especially as regards the absence of a Rule of Coordination and the substitution of “phylogenetic definition” of nomina to the use of onomatophores for the allocation of nomina to taxa; (3) a plea for “taxonomic stability” in order not to upset the traditional use of nomina and to please users of electronic data bases. These three points are here commented, as follows: (1) even with the best goodwill, under the rules of the Code it is possible to “save” only three or four of the seven new nomina of Hillis and Wilcox (2005), the others being indeed nomina nuda; furthermore, three of these seven nomina are definitively useless and redundant, being junior objective synonyms of other generic nomina; (2) the well‐known arguments against the Phylocode do not need to be repeated in detail once again, the most important one being that replacement of a secular nomenclatural system by another one, whose theoretical and practical superiority is highly questionable, would cause considerable chaos and detract taxonomists from their urgent task of accelerating the collection, study and description of the living species of our planet; (3) the claim for taxonomic and nomenclatural stability ignores the importance of the taxonomic impediment and sends a misleading message to the scientific community and to society as a whole: in the present situation of our knowledge, taxonomic stability is ignorance, and the science of taxonomy would have much to lose to adapt its concepts and practices to the needs of databases at the expense of scientific quality. It is once again stressed that, for the quality and accuracy of communication between evolutionary biologists, and above all with other biologists and non‐biologists, it is urgent that scientific periodicals impose the use of different systems of notation of nomina following distinct nomenclatural systems, such as the Code and the Phylocode.© The Willi Hennig Society 2007.
Species: kinds of individuals or individuals of a kind
Authors: Rieppel Olivier 
Published: May 2007

AbstractThe “species‐as‐individuals” thesis takes species, or taxa, to be individuals. On grounds of spatiotemporal boundedness, any biological entity at any level of complexity subject to evolutionary processes is an individual. From evolutionary theory flows an ontology that does not countenance universal properties shared by evolving entities. If austere nominalism were applied to evolving entities, however, nature would be reduced to a mere flow of passing events, each one a blob in space–time and hence of passing interest only. Yet if there is genuine biodiversity in nature, if nature is genuinely carved into species, and taxa, then these evolutionary entities will be genuinely differentiated into specific kinds, each species being one of its kind. Given the fact that evolving entities have un‐sharp boundaries, an appropriately weak, “non‐essentialist” concept of natural kind has to be invoked that does not allow for strong identity conditions. The thesis of this paper is that species are not either individuals, or natural kinds. Instead, species are complex wholes (particulars, individuals) that instantiate a specific natural kind.© The Willi Hennig Society 2007.
K‐ras oncogene silencing strategy reduces tumor growth and enhances gemcitabine chemotherapy efficacy for pancreatic cancer treatment
Authors: Réjiba Soukaina , Wack Séverine , Aprahamian Marc , Hajri Amor 
Published: May 2007

Pancreatic adenocarcinoma remains a fatal disease characterized by rapid tumor progression, high metastatic potential and profound chemoresistance. Gemcitabine is the current standard chemotherapy for advanced pancreatic cancer, but it is still far from optimal and novel therapeutic strategies are needed urgently. Mutations in the k‐ras gene have been found in more than 90% of pancreatic cancers and are believed to play a key role in this malignancy. Thus, the goal of this study was to investigate the impact of k‐ras oncogene silencing on pancreatic tumor growth. Additionally, we examined whether combining k‐ras small interfering RNA (siRNA) with gemcitabine has therapeutic potential for pancreatic cancer. The treatment of tumor cell cultures with the corresponding k‐ras siRNA resulted in a significant inhibition of k‐ras endogenous expression and cell proliferation. In vivo, tumor xenografts were significantly reduced with k‐ras siRNAGAT delivered by electroporation. Moreover, combined treatment with pSsik‐rasGAT plus gemcitabine resulted in strong growth inhibition of orthotopic pancreatic tumors. Survival rate was significantly prolonged and the mean tumor volume was dramatically reduced in mice receiving the combined treatment compared with single agents. Collectively, these findings show that targeting mutant k‐ras through specific siRNA might be effective for k‐ras oncogene silencing and tumor growth inhibition. The improvement of gemcitabine‐based chemotherapy suggests that this strategy might be used therapeutically against human pancreatic cancer to potentiate the effects of conventional therapy. (Cancer Sci 2007; 98: 1128–1136)