bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of Solubility of Nonionic Solutes in Anionic Micelle (SDS) Using a QSPR Model
Authors: Ghasemi Jahanbakhsh , Abdolmaleki Azizeh , Asadpour Saeid , Shiri Fereshteh 
Published: September 2007

AbstractA Quantitative structure–property relationships analysis has been applied to a series of chemical compounds which were of interest because of their roles in environmental samples. The incorporation neutral solute (log Ks) in anionic micelle (SDS) has been predicted by using molecular structural descriptors for a heterogeneous set of 62 neutral solutes with a range of more than 4log units. Two linear correlating models, Multiple Linear Regression (MLR) and Partial Least Squares (PLS) regression methods were used. The stepwise MLR of SPSS software was used for the selection of the variables. After variables selection, MLR and PLS methods used leave‐one‐out cross‐validation for building the regression models. Appropriate models with low standard errors and high correlation coefficients were selected. The results showed that both MLR and PLS methods could model the relationship between solubility and their electronic and thermodynamic descriptors perfectly. The predictive quality of the QSPR models were tested for an external prediction set of 11 compounds randomly chosen from 62 compounds. The squared regression coefficients of prediction for the MLR and PLS regression methods were 0.9679 and 0.9728 respectively.
Description and Application of Similarity‐Based Methods for Fast and Simple QSAR Model Development
Authors: Urbano‐Cuadrado Manuel , Luque Ruiz Irene , Gómez‐Nieto Miguel Ángel 
Published: September 2007

AbstractA molecular similarity‐based approximation to fast methodologies for developing QSAR models is presented in this paper with the aim of evaluating reliability of different similarity proposals. Inhibition of carbonic anhydrase presented by a dataset of 47 sulfonamides was the chemical framework employed to build QSAR models. A view of different chemical isomorphism extraction methods, similarity metrics, and structural difference‐based approaches is given in order to provide pharmacological chemists with fast modeling and predictive tools. Recent isomorphism detection approaches which account for dissimilarity between border atoms and bonds were also employed to analyze differences involved in scaffold substitution positions. Thus, the compounds characterization attending to several chemical criteria has been studied by principal component analysis and prediction of the inhibitory activity was carried out by partial least squares regression processes. Fingerprint‐based and approximate similarities gave the best statistical results (Q2>0.70). The latter demonstrated to be useful to detect anomalous behavior presented by very similar molecules which show very different activities. External validations (test r2≈0.90) were also carried out in order to evaluate predictions obtained for molecules which have not participated in the fitting stage.
A robust approach to the UAV task assignment problem
Authors: Alighanbari Mehdi , How Jonathan P. 
Published: September 2007

AbstractThis paper presents a new robust approach to the task assignment of unmanned aerial vehicles (UAVs) operating in uncertain dynamic environments for which the optimization data, such as target cost and target–UAV distances, are time varying and uncertain. The impact of this uncertainty in the data is mitigated by tightly integrating two approaches for improving the robustness of the assignment algorithm. One approach is to design task assignment plans that are robust to the uncertainty in the data, which reduces the sensitivity to errors in the situational awareness (SA), but can be overly conservative for long duration plans. A second approach is to replan as the SA is updated, which results in the best plan given the current information, but can lead to a churning type of instability if the updates are performed too rapidly. The strategy proposed in this paper combines robust planning with the techniques developed to eliminate churning. This combination results in the robust filter‐embedded task assignment algorithm that uses both proactive techniques that hedge against the uncertainty, and reactive approaches that limit churning behavior by the vehicles. Numerous simulations are shown to demonstrate the performance benefits of this new algorithm. Copyright © 2007 John Wiley & Sons, Ltd.
A hybrid Bayesian‐frequentist approach to evaluate clinical trial designs for tests of superiority and non‐inferiority
Authors: Shao Yongzhao , Mukhi Vandana , Goldberg Judith D. 
Published: September 2007

AbstractSpecification of the study objective of superiority or non‐inferiority at the design stage of a phase III clinical trial can sometimes be very difficult due to the uncertainty that surrounds the efficacy level of the experimental treatment. This uncertainty makes it tempting for investigators to design a trial that would allow testing of both superiority and non‐inferiority hypotheses. However, when a conventional single‐stage design is used to test both hypotheses, the sample size is based on the chosen primary objective of either superiority or non‐inferiority. In this situation, the power of the test for the secondary objective can be low, which may lead to a large loss of resources. Potentially low reproducibility is another major concern for the single‐stage design in phase III trials, because significant findings of confirmatory trials are required to be reproducible. In this paper, we propose a hybrid Bayesian‐frequentist approach to evaluate reproducibility and power in single‐stage designs for phase III trials to test both superiority and non‐inferiority. The essence of the proposed approach is to express the uncertainty that surrounds the efficacy of the experimental treatment as a probability distribution. Then one can use Bayes formula with simple graphical techniques to evaluate reproducibility and power adequacy. Copyright © 2007 John Wiley & Sons, Ltd.
“Hairy” Single‐Walled Carbon Nanotubes Prepared by Atom Transfer Radical Polymerization
Authors: Wu Wei , Tsarevsky Nicolay V. , Hudson Jared L. , Tour James M. , Matyjaszewski Krzysztof , Kowalewski Tomasz 
Published: September 2007

Abstract“Hairy nano‐objects” are hybrid nanostructures comprising a core surrounded by a “hairlike” corona of flexible polymer chains, the role of which is typically to improve the solubility of the core material or to improve its dispersability and adhesion in other polymer matrices. Both aspects could be particularly useful with carbon nanotubes, especially in their applications as reinforcing agents. The controlled synthesis of hairy carbon nanotubes is accomplished by chemical modification with 2‐bromopropionate followed by extension with poly(n‐butyl acrylate) through atom transfer radical polymerization. The obtained hairy nanotubes are visualized at nearly molecular resolution with tapping‐mode atomic force microscopy, providing insight into the uniformity of grafted chain lengths and grafting density. The grafting densities vary from ≈1.0–10.0 chains nm−1 along the nanotubes. Such a wide range of grafting density may indicate some chemical heterogeneity along and between the nanotubes; it may be also an indication of the challenges associated with carrying out chemical modification of nano‐objects having high tendency to aggregate.
In Situ Raman Spectroelectrochemical Study of 13C‐Labeled Fullerene Peapods and Carbon Nanotubes
Authors: Kalbáč Martin , Kavan Ladislav , Zukalová Markéta , Dunsch Lothar 
Published: September 2007

AbstractC60 fullerene peapods and double‐walled carbon nanotubes (DWCNTs) containing highly 13C enriched C60 and inner tubes, respectively, are studied using Raman spectroscopy and in situ Raman spectroelectrochemistry in order to follow the influence of 13C enrichment on the vibrational pattern of these carbon nanostructures. The Raman response of 13C60 after encapsulation in fullerene peapods differs from that of isotope‐natural species, NatC60. The Raman Ag(2) mode of encapsulated 13C60 is upshifted in frequency compared to that of the NatC60 peapods with the same filling factor. The chemical doping of 13C60 peapods (peapod=C60@SWCNT) with K‐vapor leads to the downshift of the Ag(2) mode, similar to the case of NatC60 peapods. The 13C60 peapods were successfully transformed into DWCNTs, which confirms high filling of single‐walled (SW) CNTs with 13C60. The DWCNTs exhibited distinctly downshifted G and D Raman modes for inner tubes, which proves that only inner tubes were enriched by 13C. The in situ Raman spectroelectrochemistry of NatC60 exhibits strong anodic enhancement, while for 13C60 peapods the enhancement is only weak. On the other hand, the electrochemical charging of the inner‐tube‐labeled DWCNTs (13Ci‐DWCNTs) followed the behavior of ordinary NatCi‐DWCNTs as indicated by in situ Raman spectroelectrochemistry. In addition, the spectroelectrochemical behavior of the G mode of inner tubes in 13 Ci‐DWCNTs is followed from the start of the electrochemical doping, which was not feasible for NatCi‐DWCNTs.
Morphology Control of Structured Polymer Brushes
Authors: Steenackers Marin , Küller Alexander , Ballav Nirmalya , Zharnikov Michael , Grunze Michael , Jordan Rainer 
Published: September 2007

AbstractThe surface‐initiated photopolymerization (SIPP) of vinyl monomers on structured self‐assembled monolayers, as defined by two‐dimensional (2D) initiator templates for polymer growth, is investigated. The 2D templates are prepared by electron‐beam chemical lithography (EBCL) of 4′‐nitro‐4‐mercaptobiphenyl (NBT) and chemical conversion to an asymmetric azo initiator (4′‐azomethylmalonodinitrile‐1,1′‐biphenyl‐4‐thiol). Ex situ kinetic studies of the SIPP process reveal a linear increase in the thickness of the polymer layer with the irradiation/polymerization time. The effect of the applied electron dosage during the EBCL process upon the final thickness of the polymer layer is also studied. The correlation between the electron‐induced conversion of the 4′‐nitro to the 4′‐amino group and the layer thickness of the resulting polymer brush indicates that the polymer‐brush grafting density can be directly controlled by the EBCL process. NBT‐based template arrays are used for the combinatorial study of the influence of the lateral structure size and the irradiation dosage on the morphology of the resulting polymer‐brush layer. Analysis of the array topography reveals the dependence of the thickness of the dry polymer layer on both electron dosage and structure size. This unique combination of EBCL as a lithographic technique to locally manipulate the surface chemistry and SIPP to amplify the created differences allows the preparation of defined polymer‐brush layers of controlled morphologies.
Charge‐Transport Behavior in Shape‐Controlled Poly(3,4‐ethylenedioxythiophene) Nanomaterials: Intrinsic and Extrinsic Factors
Authors: Yoon Hyeonseok , Hong Jin‐Yong , Jang Jyongsik 
Published: September 2007

AbstractThe charge‐transport behavior in one‐dimensional (1D) poly (3,4‐ethylenedioxythiophene) (PEDOT) nanomaterials of three different shapes is described. Both intrinsic and extrinsic factors are considered from the viewpoint of a single nanoparticle and nanoparticle assembly. Intrinsically, the oxidation level of the 1D PEDOT nanomaterials becomes higher with increasing aspect ratio of the nanomaterials, which is closely linked to the conjugation length. This result implies that the transport properties of the nanomaterials are significantly dependent on their shape. Extrinsically, the 1D PEDOT nanomaterials make an ohmic contact with gold interdigitated microelectrodes. In addition, a strong correlation is observed between the interparticle contact resistance and the shape of the nanomaterials. Lastly, the intrinsic and extrinsic factors related to charge transport are further illustrated by the resistance changes of nanomaterial‐based chemical sensors. As a result, judicious tailoring of the dimensional and geometrical characteristics of the conducting‐polymer nanomaterials may enable precise control over their transport properties as well as the characteristics of the nanomaterial‐based devices.
Comparing and evaluating computer graphics and visualization software
Authors: Laramee Robert S. 
Published: September 2007

AbstractWhen starting a new computer graphics or visualization software project, students, researchers, and businesses alike must decide whether or not to start from scratch or with third‐party software. Since computer graphics and visualization applications are typically quite large, developers often build upon existing software libraries in order to take advantage of the tens of thousands of hours worth of development and testing already invested. Thus, developers and managers must face the decision of which library to build on. We present a side‐by‐side comparison and evaluation of four popular, state‐of‐the‐art visualization and computer graphics libraries, namely the Visualization Toolkit (VTK), Open Inventor, Coin3D, and Hoops 3D. The evaluation is based on the feature set, ease of installation, development of a benchmark application, documentation, and technical support for each package. The results of our comparison and evaluation are described and recommendations are given as for whom the libraries are best suited. The VTK prevails on top in many of the aspects we compared and evaluated. Copyright © 2007 John Wiley & Sons, Ltd.
e‐Portfolios: Concepts, designs, and integration within student affairs
Authors: Garis Jeff W. 
Published: September 2007

AbstractThis chapter provides an overview of e‐portfolio concepts and designs. It describes a model that outlines an array of dimensions for the categorization of e‐portfolio systems, reviews selected systems, and makes observations regarding the importance for student affairs units to understand, collaborate, and include e‐portfolio systems within their programs and services.
Selective trellis pruning for block codes: theory and application to iterative decoding
Authors: Bertrand Eric , Labeau Fabrice 
Published: September 2007

AbstractIn this paper we present a new method to simplify trellis‐based decoding of linear block codes. Our method is based on removing (pruning) some edges and states from the trellis representation of the code; the trellis is pruned through some hard‐decisions that are made on received bits whose likelihood exceeds a predefined threshold. We show in this paper how this simplification can be accounted for by a new generator matrix (and sometimes a coset leader) that totally parametrize the new trellis, or, equivalently, the set of allowed codewords after simplification. Extensive simulations show that significant computational savings can be achieved, at a very small loss in coding performance, as long as the operating point and threshold are carefully chosen. Moreover, the application of this technique to iterative decoding of product codes is outlined, and our results show that the simplifications do not hinder the convergence, again, as long as proper parameters are chosen. Copyright © 2007 John Wiley & Sons, Ltd.
A functional analysis of KlSRB10: implications in Kluyveromyces lactis transcriptional regulation
Authors: Núñez Laura , González‐Siso Isabel , Rodríguez‐Belmonte Esther , Soengas Pilar , Lamas‐Maceiras Mónica , Cerdán Maria Esperanza 
Published: September 2007

AbstractThe function of KlSRB10 has been studied by diverse approaches. Primer extension analysis reveals several transcription start sites, position − 17 from ATG being predominant. Deletion of KlSRB10 diminishes growth in ethanol and decreases KlCYC1 transcript levels. A second phenotype associated with this deletion affects growth in galactose. These phenotypes are independent of the specific sequence connecting the ATP binding cassette and the kinase domain of Srb10p in yeasts. KlSrb10p is not necessary for LAC4 repression mediated by KlGal80p, as deduced by construction of a Klgal80Δsrb10Δ double mutant. In the two‐hybrid system, KlSrbp10p interacts with the protein encoded by KLLA0E08151g (KlSrbp11p). Copyright © 2007 John Wiley & Sons, Ltd.
Radiofrequency (RF)‐Assisted Hepatectomy May Induce Severe Postoperative Liver Damage
Authors: Mitsuo Miyazawa , Takahiro Torii , Yasuko Toshimitsu , Masayasu Aikawa , Katsuya Okada , Nozomi Shinozuka , Yoshihide Otani , Isamu Koyama 
Published: September 2007

AbstractBackgroundRadiofrequency (RF) ablation for the treatment of the section line prior to liver resection has been proposed as a way to reduce blood loss during hepatectomy. Our group compared hepatectomy with and without RF ablation to determine whether this technique actually reduces blood loss during liver resection and whether it affects the perioperative outcome.MethodOf 151 patients who underwent a hepatectomy between January 2002 and October 2005 at the Division of Gastrointestinal Surgery in the Department of Surgery of Saitama Medical University, 48 who had a partial hepatectomy or resection of a portion of liver smaller than a single Couinaud segment were included in the study. Twenty patients who had RF‐assisted hepatectomy [RF (+) group] and 28 patients who had hepatectomy without ablation [RF (‐) group] were studied to compare the rates of intraoperative blood loss and the effects of RF ablation on the perioperative outcome.ResultsIntraoperative blood loss was significantly reduced in the RF (+) group. In contrast, the alanine aminotransferase activity in the RF (+) group was significantly elevated immediately after the operation. There was no significant difference in the incidence of postoperative complications between the groups, although bile leakage did occur in three RF (+) patients.ConclusionsOur results demonstrate that the RF ablation technique can be a useful way to reduce surgical blood loss. In view of its association with severe postoperative liver damage, the technique must be applied with caution. The danger may be especially relevant to patients with chronic liver disease and decreased liver reserve.
Clinical Significance of Perioperative Immunonutrition for Patients with Esophageal Cancer
Authors: Takeuchi Hiroya , Ikeuchi Shunji , Kawaguchi Yoshiki , Kitagawa Yuko , Isobe Yoh , Kubochi Kiyoshi , Kitajima Masaki , Matsumoto Sumio 
Published: September 2007

AbstractBackgroundWe hypothesized that preoperative and/or postoperative enteral immune‐enhanced formulas that are supplemented with arginine, omega‐3 fatty acids, and RNA may reduce postoperative complications in patients undergoing esophagectomy for thoracic esophageal squamous cell carcinoma (ESCC).MethodsForty patients who underwent esophagectomy were divided into three groups: group A (n = 20) received a control enteral diet (Erental) through the jejunostomy after surgery. group B (n = 6) received an enteral diet supplemented with immune‐enhancing substrates (Impact) containing arginine, omega‐3 fatty acids, and RNA after surgery. group C (n = 14) received the impact before and after surgery.ResultsLymphocyte counts in group C on postoperative day (POD) 7 were somewhat higher than that in group A (p = 0.07) and significantly higher than in group B (p = 0.03). Furthermore the incidence of incisional wound infection in group C was significantly lower than that in group A (p = 0.03). Moreover, the duration of postoperative systemic inflammatory response syndrome (SIRS) was significantly shorter in group C than in group A (p < 0.05).ConclusionsThis study reveals that the perioperative immune‐enhanced formula may be superior to postoperative control enteral formulas in terms of reducing surgical wound infection and postoperative SIRS, which may result in serious postoperative complications for patients who have undergone esophagectomy.
Selection of breeding territory by little bustard (Tetrax tetrax) males in Central Spain: the role of arthropod availability
Authors: Traba Juan , Morales Manuel B. , García de la Morena Eladio L. , Delgado María‐Paula , Krištín Anton 
Published: September 2007

AbstractThe influence of arthropod availability on the formation of male little bustard breeding territories in central Spain was studied in two consecutive years. Arthropods (68,217 individuals) were sampled using pitfall trapping and male territories estimated by means of kernel functions. Hymenopterans (ants), beetles, mites and spiders were the main taxa found in the samples, while the highest contributions in terms of biomass came from hymenopterans, beetles and orthopterans. The only group that exhibited significant biomass differences between territory and non‐territory locations was that of the beetles; this pattern was consistent between years. Carabidae was the main beetle family in terms of biomass, followed by other large beetles such as Tenebrionidae, Cleridae, Scarabeidae and Elateridae. The biomass of Carabidae that were larger than 15 mm was significantly higher within territories than outside them. The biomass of Cleridae was greater in fallows, while Elateridae were more abundant in arable fields. The total biomass of beetles that were larger than 15 mm was higher in arable fields than in fallows. Family richness differed between years, while diversity showed differences between agricultural fields (it was highest in fallows), although these variables did not differ between territory and non‐territory locations. Results indicate that large beetles (particularly carabids) seem to be a valuable food resource that is defended by little bustard males during the highly energy‐demanding breeding season, which is discussed here in relation to habitat selection, the mating system and its implications for the conservation of the species.
Role of carbohydrate moiety of bleomycin‐A2 in caspase‐3 activation and internucleosomal chromatin fragmentation in apoptosis of laryngeal carcinoma cells
Authors: Brahim Souhir , Abid Kaouthar , Kenani Abderraouf 
Published: September 2007

AbstractBleomycin (BLM), an antitumor antibiotic, is currently used during anticancer therapy. The therapeutic efficiency of BLM for the treatment of malignant tumors is related to its ability to cleave DNA. However, little is known about the biological activity of the glycannic moiety in BLM‐induced cytotoxicity. In this study, cell death induced by BLM‐A2 and deglycosylated BLM‐A2 was studied in a laryngeal carcinoma cell line (HEp‐2 cells). Our results indicate that HEp‐2 cells showed morphological and biochemical changes associated with apoptosis in the presence of low concentrations of BLM‐A2. In contrast, the same changes, except activation of caspase‐3 and internucleosomal digestion of genomic DNA, were observed when cells were exposed to high concentrations of deglycosylated BLM‐A2. These observations indicate that the glycannic moiety from the bleomycin molecule has important biological effects on the cytotoxicity of the drug.