bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved Auxiliary for the Synthesis of Medium‐Sized Bis(lactams)
Authors: Springer Jasper , Jansen T. Paul , Ingemann Steen , Hiemstra Henk , van Maarseveen Jan H.
Published: November 2007

Our auxiliary‐based method for the synthesis of bis(lactams) has been optimized. A novel auxiliary is described that is inserted in the backbone of a linear peptide facilitating the mutually reactive terminal groups to approach one another for a cyclization reaction. A subsequent ring contraction mechanism leads to the bis(lactams) with the remainings of the auxiliary still attached. Functionalized seven‐ and eight‐membered bis(lactams) have been prepared that are difficult to access using traditional methods. Removal of the auxiliary from the bis(lactams) has been described with the possible side reactions that can occur.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Catalysis by Ionic Liquids: Significant Rate Acceleration with the Use of [pmIm]Br in the Three‐Component Synthesis of Dithio­carbamates
Authors: Ranu Brindaban C. , Saha Amit , Banerjee Subhash
Published: November 2007

An easily accessible neutral ionic liquid, 1‐methyl‐3‐pentylimidazolium bromide, promoted a one‐pot three‐component condensation of an amine, carbon disulfide, and an activated alkene/dichloromethane/epoxide to produce the corresponding dithiocarbamates in high yields at room temperature. The reactions are very fast in ionic liquids relative to those in other reaction media. These reactions do not require any additional catalyst or solvent. The ionic liquid can be recovered and recycled for subsequent reactions. A plausible mechanism is suggested. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Effect of Varying the Anionic Component of a Copper(I) Catalyst on Homologation of Arylacetylenes to Allenes by the Mannich Reaction
Authors: Kumar Vipan , Chipeleme Alex , Chibale Kelly
Published: November 2007

The effect of varying the anionic component of a copper(I) catalyst in the homologation of terminal arylacetylenes to allenes by the Mannich reaction was investigated. Varying amounts of allenes, Mannich bases and dimers were obtained depending on the nature of the anionic component of the copper catalyst. On the other hand, Eglinton–Glaser dimerizations were achieved in high yields with 0.5 equiv. of triethylamine. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis and Rearrangement of Dewar Benzenes Into Biaryls: Experimental Evidence for Conrotatory Ring Opening
Authors: Janková Štěpánka , Dračínský Martin , Císařová Ivana , Kotora Martin
Published: November 2007

Rearrangement of aryl‐substituted Dewar benzenes into the corresponding biaryls may serve as an alternative pathway for synthesis of sterically hindered biaryls. The kinetic data obtained from thermal rearrangements of Dewar benzenes provide experimental evidence for the proposed orbital‐symmetry‐controlled electrocyclic ring opening. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Cationic P(OPh)3‐ or PPh3‐Rhodium(I) Complex‐Catalyzed Isomerizations of 5‐Alkynals to δ‐Alkynyl Ketones, Cyclopent‐1‐enyl Ketones, and Cyclohexenones (Eur. J. Org. Chem. 34/2007)
Authors: Tanaka Ken , Sasaki Kaori , Takeishi Kenzo , Hirano Masao
Published: November 2007

The cover picture shows the cationic rhodium(I) complex catalyzed isomerization of 5‐alkynals to four different types of ketones. The catalytic isomerization of 5‐alkynals to δ‐alkynyl ketones and cyclopent‐1‐enyl ketones proceeds by using RhI+/P(OPh)3, whereas the catalytic endo/trans and exo/cis hydroacylation of 5‐alkynals to cyclohexenones and cyclopentanones proceeds by using RhI+/PPh3 and RhI+/BINAP, respectively. The ligands of the Rh catalysts and the substituents at the 4‐position of the 5‐alkynals play an important role in determining which isomerization product results. Details are discussed in the article by K. Tanaka et al. on p. 5675 ff.
A risk‐based approach for bidding strategy in an electricity pay‐as‐bid auction
Authors: Sadeh Javad , Mashhadi Habib Rajabi , Latifi Mohammad Amin
Published: November 2007

With the reform of electric power industry and the development of electrical energy markets in many countries, it is of significance to develop bidding strategies for generation companies (GenCos). In this environment, one of the most challenging and important tasks for a GenCo is developing effective strategies to optimize hourly offer curve. In this paper, focusing on Iran's electricity market structure, we model the bidding problem from the viewpoint of a GenCo in a pay‐as‐bid (PAB) auction. Our goal is to present a tool for determining the optimal bidding strategy of a price‐taker producer in an electricity PAB auction taking into account the relevant risks. Due to uncertainties in power market, the market‐clearing price (MCP) of each hour is assumed to be known as a probability density function (pdf). The optimal solution of bidding problem is obtained analytically based on the classical optimization theory. Also, the analytical solution for a multi‐step bid protocol is generalized and the properties of the generalized solution are discussed. A model is developed to consider concept of risk using two different methods. The two proposed methods are then compared and the results interpreted using numerical examples. In addition, the effect of variation of MCP's pdf parameters on supplier's profit is studied. Copyright © 2007 John Wiley & Sons, Ltd.
Directional functional coupling of cerebral rhythms between anterior cingulate and dorsolateral prefrontal areas during rare stimuli: A directed transfer function analysis of human depth EEG signal
Authors: Brázdil Milan , Babiloni Claudio , Roman Robert , Daniel Pavel , Bareš Martin , Rektor Ivan , Eusebi Fabrizio , Rossini Paolo Maria , Vecchio Fabrizio
Published: November 2007

What is the neural substrate of our capability to properly react to changes in the environment? It can be hypothesized that the anterior cingulate cortex (ACC) manages repetitive stimuli in routine conditions and alerts the dorsolateral prefrontal cortex (PFC) when stimulation unexpectedly changes. To provide evidence in favor of this hypothesis, intracerebral stereoelectroencephalographic (SEEG) data were recorded from the anterior cingulate and dorsolateral PFC of eight epileptic patients in a standard visual oddball task during presurgical monitoring. Two types of stimuli (200 ms duration) such as the letters O (frequent stimuli; 80% of probability) and X (rare stimuli) were presented in random order, with an interstimulus interval between 2 and 5 s. Subjects had to mentally count the rare (target) stimuli and to press a button with their dominant hand as quickly and accurately as possible. EEG frequency bands of interest were θ (4–8 Hz), α (8–12 Hz), β (14–30 Hz), and γ (30–45 Hz). The directionality of the information flux within the EEG rhythms was indexed by a directed transfer function (DTF). The results showed that compared with the frequent stimuli, the target stimuli induced a statistically significant increase of DTF values from the anterior cingulate to the dorsolateral PFC at the θ rhythms (P < 0.01). These results provide support to the hypothesis that ACC directly or indirectly affects the oscillatory activity of dorsolateral PFC by a selective frequency code under typical oddball conditions. Hum Brain Mapp 2009. © 2007 Wiley‐Liss, Inc.
A stromal gene signature associated with inflammatory breast cancer
Authors: Boersma Brenda J. , Reimers Mark , Yi Ming , Ludwig Joseph A. , Luke Brian T. , Stephens Robert M. , Yfantis Harry G. , Lee Dong H. , Weinstein John N. , Ambs Stefan
Published: November 2007

The factors that determine whether a breast carcinoma will develop into inflammatory breast cancer (IBC) remain poorly understood. Recent evidence indicates that the tumor stroma influences cancer phenotypes. We tested the hypotheses that the gene expression signature of the tumor stroma is a distinctive feature of IBC. We used laser capture microdissection to obtain enriched populations of tumor epithelial cells and adjacent stromal cells from 15 patients with IBC and 35 patients with invasive, noninflammatory breast cancer (non‐IBC). Their mRNA expression profiles were assessed using Affymetrix GeneChips™. In addition, a previously established classifier for IBC was evaluated for the resulting data sets. The gene expression profile of the tumor stroma distinguished IBC from non‐IBC, and a previously established IBC prediction signature performed better in classifying IBC using the gene expression profile of the tumor stroma than it did using the profile of the tumor epithelium. In a pathway analysis, the genes differentially expressed between IBC and non‐IBC tumors clustered in distinct pathways. We identified multiple pathways related to the endoplasmic stress response that could be functionally significant in IBC. Our findings suggest that the gene expression in the tumor stroma may play a role in determining the IBC phenotype. © 2007 Wiley‐Liss, Inc.
Differential sensitivity of human colon cancer cell lines to the nucleoside analogs ARC and DRB
Authors: Bhat Uppoor G. , Gartel Andrei L.
Published: November 2007

Recently, we identified a nucleoside analog named ARC (4‐amino‐6‐hydrazino‐7‐β‐D‐ribofuranosyl‐7H‐Pyrrolo[2,3‐d]pyrimidine‐5‐carboxamide), which has the properties of a general transcriptional inhibitor. Here, we report the characterization of ARC on a panel of colorectal cancer (CRC) cell lines. Cell death induced by ARC in CRC cells was accompanied by caspase‐3 cleavage and correlated with the downregulation of antiapoptotic proteins, survivin and Mcl‐1 and with the inhibition of Akt phosphorylation. At the same time, colon cancer cell lines were resistant to the well–known nucleoside analog DRB (5,6‐dichloro‐1‐β‐D‐ribofuranosylbenzimidazole), which failed to downregulate Mcl‐1 or survivin. Overall, ARC could represent an attractive candidate for anti‐cancer drug development that targets multiple survival pathways in colon cancer cells. © 2007 Wiley‐Liss, Inc.
Extracellular matrix and HIF‐1 signaling: The role of prolidase
Authors: Surazynski Arkadiusz , Donald Steven P. , Cooper Sandra K. , Whiteside Martin A. , Salnikow Konstantin , Liu Yongmin , Phang James M.
Published: November 2007

Hypoxia‐inducible factor‐1 (HIF‐1) plays an important role in stress‐responsive gene expression. Although primarily sensitive to hypoxia, HIF‐1 signaling can be regulated by a number of stress factors including metabolic stress, growth factors and molecules present in the extracellular matrix (ECM). Degradation of ECM by metalloproteinases (MMP) is important for tumor progression, invasion and metastasis. ECM is predominantly collagen, and the imino acids (Pro and HyPro) comprise 25% of collagen residues. The final step in collagen degradation is catalyzed by prolidase, the obligate peptidase for imidodipeptides with Pro and HyPro in the carboxyl terminus. Defective wound healing in patients with inherited prolidase deficiency is associated with histologic features of angiopathy suggesting that prolidase may play a role in angiogenesis. Because HIF‐1α is central to angiogenesis, we considered that prolidase may modulate this pathway. To test this hypothesis, we made expression constructs of human prolidase and obtained stable transfectants in colorectal cancer cells (RKO). Overexpression of prolidase resulted in increased nuclear hypoxia inducible factor (HIF‐1α) levels and elevated expression of HIF‐1−dependent gene products, vascular endothelial growth factor (VEGF) and glucose transporter‐1 (Glut‐1). The activation of HIF‐1‐dependent transcription was shown by prolidase‐dependent activation of hypoxia response element (HRE)‐luciferase expression. We used an oxygen‐dependent degradation domain (ODD)‐luciferase reporter construct as a surrogate for HIF‐1α as an in situ prolyl‐hydroxylase assay. Since this reporter is degraded by VHL‐dependent mechanisms, the increased levels of luciferase observed with prolidase expression reflected the decreased HIF‐1α prolyl hydroxylase activity. Additionally, the differential expression of prolidase in 2 breast cancer cell lines showed prolidase‐dependent differences in HIF‐1α levels. These findings show that metabolism of imidodipeptides by prolidase plays a previously unrecognized role in angiogenic signaling. © 2007 Wiley‐Liss, Inc.
Biophysical Response to Pulsed Laser Microbeam‐Induced Cell Lysis and Molecular Delivery
Authors: Hellman Amy N. , Rau Kaustubh R. , Yoon Helen H. , Venugopalan Vasan
Published: November 2007

Cell lysis and molecular delivery in confluent monolayers of PtK2 cells are achieved by the delivery of 6 ns, λ = 532 nm laser pulses via a 40×, 0.8 NA microscope objective. With increasing distance from the point of laser focus we find regions of (a) immediate cell lysis; (b) necrotic cells that detach during the fluorescence assays; (c) permeabilized cells sufficient to facilitate the uptake of small (3 kDa) FITC‐conjugated Dextran molecules in viable cells; and (d) unaffected, viable cells. The spatial extent of cell lysis, cell detachment, and molecular delivery increased with laser pulse energy. Hydrodynamic analysis from time‐resolved imaging studies reveal that the maximum wall shear stress associated with the pulsed laser microbeam‐induced cavitation bubble expansion governs the location and spatial extent of each of these regions independent of laser pulse energy. Specifically, cells exposed to maximum wall shear stresses τw, max > 190 ± 20 kPa are immediately lysed while cells exposed to τw, max > 18 ± 2 kPa are necrotic and subsequently detach. Cells exposed to τw, max in the range 8–18 kPa are viable and successfully optoporated with 3 kDa Dextran molecules. Cells exposed to τw, max < 8 ± 1 kPa remain viable without molecular delivery. These findings provide the first direct correlation between pulsed laser microbeam‐induced shear stresses and subsequent cellular outcome. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Unified QSAR and network‐based computational chemistry approach to antimicrobials, part 1: Multispecies activity models for antifungals
Authors: GonzÁlez‐DÍaz Humberto , Prado‐Prado Francisco J.
Published: November 2007

There are many pathogen microbial species with very different antimicrobial drugs susceptibility. In this work, we selected pairs of antifungal drugs with similar/dissimilar species predicted‐activity profile and represented it as a large network, which may be used to identify drugs with similar mechanism of action. Computational chemistry prediction of the biological activity based on quantitative structure–activity relationships (QSAR) susbtantially increases the potentialities of this kind of networks, avoiding time and resource‐consuming experiments. Unfortunately, most QSAR models are unspecific or predict activity against only one species. To solve this problem we developed a multispecies QSAR classification model, in which the outputs were the inputs of the aforementioned network. Overall model classification accuracy was 87.0% (161/185 compounds) in training, 83.4% (50/61) in validation, and 83.7% for 288 additional antifungal compounds used to extend model validation for network construction. The network predicted has 59 nodes (compounds), 648 edges (pairs of compounds with similar activity), low coverage density d = 37.8%, and distribution more close to normal than to exponential. These results are more characteristic of a not‐overestimated random network, clustering different drug mechanisms of actions, than of a less useful power law network with few mechanisms (network hubs). © 2007 Wiley Periodicals, Inc. J Comput Chem 2008
A self‐organizing algorithm for molecular alignment and pharmacophore development
Authors: Bandyopadhyay Deepak , Agrafiotis Dimitris K.
Published: November 2007

We present a method for simultaneous three‐dimensional (3D) structure generation and pharmacophore‐based alignment using a self‐organizing algorithm called Stochastic Proximity Embedding (SPE). Current flexible molecular alignment methods either start from a single low‐energy structure for each molecule and tweak bonds or torsion angles, or choose from multiple conformations of each molecule. Methods that generate structures and align them iteratively (e.g., genetic algorithms) are often slow. In earlier work, we used SPE to generate good‐quality 3D conformations by iteratively adjusting pairwise distances between atoms based on a set of geometric rules, and showed that it samples conformational space better and runs faster than earlier programs. In this work, we run SPE on the entire ensemble of molecules to be aligned. Additional information about which atoms or groups of atoms in each molecule correspond to points in the pharmacophore can come from an automatically generated hypothesis or be specified manually. We add distance terms to SPE to bring pharmacophore points from different molecules closer in space, and also to line up normal/direction vectors associated with these points. We also permit pharmacophore points to be constrained to lie near external coordinates from a binding site. The aligned 3D molecular structures are nearly correct if the pharmacophore hypothesis is chemically feasible; postprocessing by minimization of suitable distance and energy functions further improves the structures and weeds out infeasible hypotheses. The method can be used to test 3D pharmacophores for a diverse set of active ligands, starting from only a hypothesis about corresponding atoms or groups. © 2007 Wiley Periodicals, Inc. J Comput Chem 2008
On the applicability of multireference second‐order perturbation theory to study weak magnetic coupling in molecular complexes
Authors: Queralt Núria , Taratiel David , de Graaf Coen , Caballol Rosa , Cimiraglia Renzo , Angeli Celestino
Published: November 2007

The performance of multiconfigurational second‐order perturbation techniques is established for the calculation of small magnetic couplings in heterobinuclear complexes. Whereas CASPT2 gives satisfactory results for relatively strong magnetic couplings, the method shows important deviations from the expected Heisenberg spectrum for couplings smaller than 15–20 cm−1. The standard choice of the zeroth‐order CASPT2 Hamiltonian is compared to alternative definitions published in the literature and the stability of the results is tested against increasing level shifts. Furthermore, we compare CASPT2 with an alternative implementation of multiconfigurational perturbation theory, namely NEVPT2 and with variational calculations based on the difference dedicated CI technique. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Linear‐scaling Cholesky decomposition
Authors: Schweizer Sabine , Kussmann Jörg , Doser Bernd , Ochsenfeld Christian
Published: November 2007

We present linear‐scaling routines for the calculation of the Cholesky decomposition of a symmetric positive‐definite matrix and its inverse. As an example, we consider the inversion of the overlap matrix of DNA and amylose fragments as well as of linear alkanes, where the largest system corresponds to a 21,442 × 21,442 matrix. The efficiency and the scaling behavior are discussed and compared to standard LAPACK routines. Our Cholesky routines are publicly available on the web. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Chondrogenesis and ossification of the lissamphibian pectoral girdle
Authors: Shearman Rebecca M.
Published: November 2007

Knowledge of amphibian shoulder development is requisite for further understanding of gnathostome pectoral girdle evolution. Fish and amniotes share few pectoral girdle elements, but modern amphibians exhibit a unique combination of traits that bridge the morphological gap between these two groups. I analyzed patterns of chondrogenesis, ossification, and bone histology of the pectoral girdles of two anuran species (Xenopus laevis and Bombina orientalis) and two urodele species (Ambystoma mexicanum and Desmognathus aeneus) to provide new insight into the evolution of the tetrapod pectoral girdle. Comparisons reveal the following: 1) variation in the pattern of chondrogenesis among the anuran species analyzed correlates to variation in adult pectoral girdle morphology; 2) morphologically similar pectoral skeletons do not necessarily have similar patterns of bone histology; and 3) the urodele and anuran pectoral girdles included herein share a common morphology despite differences in patterns of chondrogenesis. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
Renal sexual segment of the Cottonmouth snake, Agkistrodon piscivorous (Reptilia, Squamata, Viperidae)
Authors: Sever David M. , Siegel Dustin S. , Bagwill April , Eckstut Mallory E. , Alexander Laura , Camus Angelle , Morgan Colby
Published: November 2007

The seasonal variation of the renal sexual segment (RSS) of males of the Cottonmouth snake, Agkistrodon piscivorous, is described using light and electron microscopy. This study is the first to describe the ultrastructure of the RSS of a viper (Viperidae) and only the fourth on a snake. Renal sexual segments from males collected February to May and from August to November are similar in appearance. The cells are eosinophilic and react with periodic acid/Schiff procedure (PAS) for neutral carbohydrates and bromphenol blue (BB) for proteins. At the ultrastructure level, the cells contain large (2 μm diameter), electron‐dense secretory granules and smaller vesicles with a diffuse material, and these structures abut against the luminal border and upon clear vacuoles continuous with intercellular canaliculi. Evidence was found for both apocrine and merocrine processes of product release. In June and July, the RSS are significantly smaller in diameter, largely basophilic, and have only scattered granules that are PAS+ and BB+. Cytologically, the RSS from June to July lack electron‐dense secretory granules and the smaller vesicles with diffuse material. Numerous condensing vacuoles and abundant rough endoplasmic reticulum, however, indicate that active product synthesis is occurring. This is the first report of significant seasonal variation in the histology and ultrastructure of the RSS of a snake, although such reports exist for lizards. The seasons when the RSS is most highly hypertrophied correspond to the fall and spring mating seasons of A. piscivorous, as determined by other studies. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
Organic and inorganic selenium speciation in environmental and biological samples by nanometer‐sized materials packed dual‐column separation/preconcentration on‐line coupled with ICP‐MS
Authors: Huang Chaozhang , Hu Bin , He Man , Duan Jiankun
Published: November 2007

A novel, fast, and cheap nonchromatographic method for direct speciation of dissolved inorganic and organic selenium species in environmental and biological samples was developed by flow injection (FI) dual‐column preconcentration/separation on‐line coupled with ICP‐MS determination. In the developed technique, the first column packed with nanometer‐sized Al2O3 could selectively adsorb the inorganic selenium [Se(IV), Se(VI)], and the retained inorganic selenium could be eluted by 0.2 mol l−1 NaOH, while the organic Se [selenocystine (SeCys2) and selenomethionine (Se–Met)] was not retained. On the other hand, the second column packed with mesoporous TiO2 chemically modified by dimercaptosuccinic acid (DMSA) could selectively adsorb Se(IV) and SeCys2 and barely adsorb Se(VI) and Se–Met. When the sample solution was passed through the column 1, separation of inorganic selenium and organic selenium could be achieved first. Then, the effluent from column 1 was successively introduced into the column 2 and the speciation of organic selenium could be attained due to the different adsorption behaviors of Se–Met and SeCys2 on DMSA modified TiO2. After that, the eluent from column 1 contained Se(IV), and Se(VI) was adjusted to desired pH and injected into column 2, and the speciation of Se(IV) and Se(VI) could also be realized thanks to their different retention on column 2. The parameters affecting the separation were investigated systematically and the optimal separation conditions were established. The detection limits obtained for Se(IV), Se(VI), Se–Met and SeCys2 were 45–210 ng l−1 with precisions of 3.6–9.7%. The proposed method has been successfully applied for the speciation of dissolved inorganic and organic selenium in environmental and biological samples. In order to validate the methodology, the developed method was also applied to the speciation of selenium in certified reference material of SELM‐1 yeast, and the determined values were in good agreement with the certified values. Copyright © 2007 John Wiley & Sons, Ltd.
The sodium ion affinities of cytosine and its methylated derivatives
Authors: Wang Ping , Polce Michael J. , Ohanessian Gilles , Wesdemiotis Chrys
Published: November 2007

The sodium ion affinities of cytosine (Cyt), 5‐methylcytosine (5MeCyt) and 1‐methylcytosine (1MeCyt) have been determined by experimental and quantum chemical methods. Na+‐bound heterodimers were produced carrying one cytosine or methylated cytosine ligand (designated as C) and one peptide or amino acid reference base (designated as Pep); the Pep molecules included the peptides GlyLeu, GlyPhe, SerGly, and PheGly, and the amino acid His. The dissociation kinetics of these CNa+Pep ions were determined by collisionally activated dissociation (CAD) and converted to relative and absolute Na+ affinities via kinetic method approaches. Relative Na+ affinities increase in the order (kJ/mol): GlyLeu (0) < Cyt (3) < GlyPhe (4) < SerGly (6) < 5MeCyt (8) < PheGly (11) < 1MeCyt (13) < His (17). Anchoring the relative values of the nucleobases to the absolute affinities of the reference bases leads to absolute Na+ affinities of 214 ± 8, 219 ± 8, and 224 ± 8 kJ/mol for Cyt, 5MeCyt, and 1MeCyt, respectively. Ab initio calculations were used to confirm these results. The computed affinities of Cyt (213 kJ/mol) and 1MeCyt (217 kJ/mol) are in very good agreement with the experiments. These values unambiguously correspond to Na+ complexes with the keto form of cytosine and its methyl derivatives. Ab initio calculations on tautomerization mechanisms in the gas versus condensed phase are used to discuss why the sodiated keto isomers were formed in the present electrospray ionization (ESI) experiments, but the enol isomers in previous fast atom bombardment (FAB) experiments. Copyright © 2007 John Wiley & Sons, Ltd.
Links between circulation weather types and teleconnection patterns and their influence on precipitation patterns in Galicia (NW Spain)
Authors: Lorenzo M. N. , Taboada J. J. , Gimeno L.
Published: November 2007

An automated version of the Lamb weather type classification scheme was used to study the relationship between atmospheric circulation patterns and rainfall in the northwestern part of the Iberian Peninsula, which is an important area of crossing influences of the different teleconnection patterns of the Northern Hemisphere. We calculated the correlation between the most important teleconnection patterns that affect this area and the different types of weather circulation. In this area, anticyclone weather types are the most frequent in any part of the year. The frequency of occurrence of W and SW situations is also significant in autumn and winter. The correlation between weather types (WT) and teleconnection patterns showed that the North Atlantic Oscillation (NAO) index has significant correlations only in winter, while other patterns, such as the Eastern Atlantic (EA), have significant correlations in the other seasons. As a result of these correlations, the EA is a more relevant pattern than the NAO for describing the Galician climate throughout the year. We also calculated correlations between the North Hemisphere Annular Mode (NAM) and the different types of weather types. The NAM shows significant correlations throughout the year. Hence, the NAM is more relevant than the NAO, which is its local manifestation. Copyright © 2007 Royal Meteorological Society
Pharmacokinetics of isolated lung perfusion with melphalan for resectable pulmonary metastases, a phase I and extension trial
Authors: Grootenboers Marco JJ H. , Hendriks Jeroen M.H. , van Boven Wim J. , Knibbe Catherijne A.J. , van Putte Bart , Stockman Bernard , De Bruijn Ernst , Vermorken Jan B. , Van Schil Paul E.Y. , Schramel Franz MNH
Published: November 2007

Background

Isolated lung perfusion (ILuP) with melphalan was performed under normo‐ and hyperthermic conditions combined with pulmonary metastasectomy for patients with resectable lung metastases. We present the results of pharmacokinetic analysis of a phase I and extension trial.

Methods

Twenty‐one procedures of ILuP with melphalan were performed in the phase I trial according to a dose‐escalation schedule under normothermic and hyperthermic conditions followed by surgical resection of pulmonary metastases. In an extension trial 8 additional procedures with 15 and 45 mg melphalan were performed under hyperthermic conditions. Samples of serum, perfusate, lung, and tumor tissue were obtained.

Results

High perfusate concentrations of melphalan were recorded in contrast to low systemic concentrations. Marked interindividual variability was observed in melphalan concentrations in perfusate, tumor, and lung tissue. Statistically significant correlation between melphalan dose, and perfusate area under the concentration–time curve (R2 = 0.578, P = 0.001) and lung tissue concentrations (R2 = 0.459, P = 0.028) were noted. No significant correlation between melphalan dose and tumor tissue concentrations could be established.

Conclusion

Isolated lung perfusion effectively delivers high doses of melphalan to the lung and tumor tissues with minimal systemic levels. Significant correlation between perfused melphalan dose, perfusate area under the concentration–time curve and lung tissue melphalan concentrations were observed. J. Surg. Oncol. 2007;96:583–589. © 2007 Wiley‐Liss, Inc.
Vacuum‐assisted closure for radiation‐associated wound complications
Authors: Siegel Herrick J. , Long James L. , Watson Kevin M. , Fiveash John B.
Published: November 2007

Background and Objectives

Vacuum‐assisted closure (VAC) technology has proven to be effective in the management of soft tissue loss from infections, vascular insufficiency, and traumatic disorders and may have a similar benefit in the musculoskeletal oncology patient. This study reports a single institution's experience with VAC technology in the management of radiation‐associated wound complications in patients with soft tissue sarcomas.

Materials

Twenty‐two patients treated with both surgical intervention and radiation therapy developed either superficial or deep wound complications that were managed with the VAC device. This study group was compared to a retrospectively identified comparison group of 19 patients, in which the VAC device was not used.

Results

Hospital stay (P < 0.025), length of overall treatment (P < 0.025), number of operative debridements (P < 0.05) and success of wound closure without the need for soft tissue transposition (P < 0.01) was found to be significantly less in the study groups as compared to those not treated with the VAC device.

Conclusion

VAC technology appears to be safe and effective in the treatment of radiation‐associated wound complications. J. Surg. Oncol. 2007;96:575–582. © 2007 Wiley‐Liss, Inc.
Actively Q-switched all-fiber lasers
Authors: Andrés M V , Cruz J L , Díez A , Pérez-Millán P , Delgado-Pinar M
Published: November 2007

Q-switching of fiber lasers using bulk elements has important drawbacks as reduced mechanical stability and high insertion losses. The development of efficient all-fiber modulation techniques is the key to obtain robust, compact and efficient Q-switched all-fiber lasers.

Certainly, the development of fiber Bragg gratings (FBG) has been crucial to make progress on fiber lasers. FBGs permit a simple way to assemble all-fiber laser cavities and can be written in the active fiber itself. The Q-factor of this type of cavities is determined by the reflectivity of the FBGs and the losses of the fiber. Here, we focus on the use of magnetostrictive materials and the acousto-optic interaction to develop efficient Q-factor modulators. Most of these modulators include an FBG and take advantage of the specific interaction of the magnetostrictive materials or the acoustic wave with the FBG itself.

Fiber optic technologies permit the development of a rather unique type of fiber lasers, i.e., actively Q-switched distributed feedback (DFB) fiber lasers. In this case, both the use of magnetostrictive materials and the acousto-optic interaction permit the generation of dynamic defects in an FBG that has been previously written in a highly Er-doped fiber.
Switchable erbium-doped fiber laser using optical-injection controlling
Authors: Yu N , Zhan L , Xing L , Luo S Y , Xia Y X
Published: November 2007

In this paper, we propose and demonstrate a new wavelength-switchable fiber laser with all-optical controlling. By adjusting the power of injected light in a cascaded fiber Bragg grating overlapping cavity erbium-doped fiber laser, we obtained the switching among dual wavelength, single wavelength and zero wavelength. Meanwhile, the effect of optical injection in erbium-doped fiber laser was investigated, and the optimized wavelength to control the lasing wavelength has been found.
Continuous-wave laser operation at 1.33 μm of Nd:CNGG and Nd:CLNGG crystals
Authors: Shi Z B , Fang X , Zhang H J , Wang Z P , Wang J Y , Yu H H , Yu Y G , Tao X T , Jiang M H
Published: November 2007

With a laser-diode (LD) as the pump source, continuous-wave (cw) laser performance at 1.33 μm of Nd:CNGG and Nd:CLNGG crystals was demonstrated for the first time. The maximum power of 158 mW and 141 mW from Nd:CNGG and Nd:CLNGG lasers were obtained with the corresponding optical conversion efficiencies of 1.3% and 1.5%, and slope efficiencies of 2.0% and 2.9%, respectively. The difference between the laser performance of Nd:CNGG and Nd:CLNGG crystals was also discussed.
Continuous-wave laser performance of Nd:LuxGd1-xVO4 operating at 1.34 μm
Authors: Yu H H , Zhang H J , Wang Z P , Wang J Y , Yu Y G , Jiang M H
Published: November 2007

Laser-diode pumped continuous-wave (cw) laser performance of a new class Nd:LuxGd1-xVO4 crystals at 1.34 μm was demonstrated for the first time to our knowledge. A maximum output power of 2.25 W was obtained at the incident pump power of 11.96 W with x = 0.14, giving the corresponding optical conversion efficiency of 18.8%. Efficient emission cross-sections of the mixed crystals were calculated for different x. The influence of Lu composition x on the variations of laser performance and emission cross-section was also discussed.
A high efficient one-end-pumped TEM00 laser with optimal pump mode
Authors: Yan X , Liu Q , Huang L , Wang Y , Huang X , Wang D , Gong M
Published: November 2007

An one-end-pumped Nd:YVO4 laser with fiber- coupled diode is designed. The mode matching between pump mode and laser mode is analyzed, and the optimum mode matching coefficient is obtained by optimizing the pump mode. Based on the optimal pump mode, a 14.2W TEM00 mode CW laser is obtained with a optical-optical efficiency of 55.7% at 1064 nm, with M
2 factors of M
2
x = 1.16, M
2
y = 1.15. In Q-switching operation, 13.8W average power at a pulse repetition rate of 200 kHz is produced, with a stability of pulse peak value < 5%.
Understanding and assessing land degradation—comments on research in Chuquisaca, Bolivia
Authors: Preston D. A.
Published: November 2007

A recent paper in this journal offers observations and research findings on apparent land degradation in three areas of the Andean valleys in the Department of Chuquisaca, Bolivia. It is suggested that the evidence of an increase in degradation during the past 40 years is unconvincing and a possible link with population increase is inconclusive. The landscape is naturally one where land degradation is frequently visible, sometimes catastrophic, and widespread, whatever the use of natural resources by humans. The paper is potentially valuable for its use of data based on farmer consultation but fails to recognise that farming is only one of many activities for rural households. Copyright © 2007 John Wiley & Sons, Ltd.
p53 regulates FAK expression in human tumor cells
Authors: Golubovskaya Vita M. , Finch Richard , Kweh Frederick , Massoll Nicole A. , Campbell‐Thompson Martha , Wallace Margaret R. , Cance William G.
Published: November 2007

Attenuation of the p53 protein is one of the most common abnormalities in human tumors. Another important marker of tumorigenesis is focal adhesion kinase (FAK), a 125‐kDa tyrosine kinase that is overexpressed at the mRNA and protein levels in a variety of human tumors. FAK is a critical regulator of adhesion, motility, metastasis, and survival signaling. We have characterized the FAK promoter and demonstrated that p53 can inhibit the FAK promoter activity in vitro. In the present study, we showed that p53 can bind the FAK promoter‐chromatin region in vivo by chromatin immunoprecipitation (ChIP) assay. Furthermore, we demonstrated down‐regulation of FAK mRNA and protein levels by adenoviral overexpression of p53. We introduced plasmids with different mutations in the DNA‐binding domain of p53 (R175H, p53 R248W and R273H) into HCTp53−/− cells and showed that these mutations of p53 did not bind FAK promoter and did not inhibit FAK promoter activity, unlike wild type p53. We analyzed primary breast and colon cancers for p53 mutations and FAK expression, and showed that FAK expression was increased in tumors containing mutations of p53 compared to tumors with wild type p53. In addition, tumor‐derived missense mutations in the DNA‐binding domain (R282, R249, and V173) also led to increased FAK promoter activity. Thus, the present data show that p53 can regulate FAK expression during tumorigenesis. © 2007 Wiley‐Liss, Inc.
Global existence for a contact problem with adhesion
Authors: Bonetti Elena , Bonfanti Giovanna , Rossi Riccarda
Published: November 2007

In this paper, we analyze a contact problem with irreversible adhesion between a viscoelastic body and a rigid support. On the basis of Frémond's theory, we detail the derivation of the model and of the resulting partial differential equation system. Hence, we prove the existence of global in time solutions (to a suitable variational formulation) of the related Cauchy problem by means of an approximation procedure, combined with monotonicity and compactness tools, and with a prolongation argument. In fact the approximate problem (for which we prove a local well‐posedness result) models a contact phenomenon in which the occurrence of repulsive dynamics is allowed for. We also show local uniqueness of the solutions, and a continuous dependence result under some additional assumptions. Copyright © 2007 John Wiley & Sons, Ltd.
Human mitochondrial transfer RNAs: Role of pathogenic mutation in disease
Authors: Scaglia Fernando , Wong Lee‐Jun C.
Published: November 2007

The human mitochondrial genome encodes 13 proteins. All are subunits of the respiratory chain complexes involved in energy metabolism. These proteins are translated by a set of 22 mitochondrial transfer RNAs (tRNAs) that are required for codon reading. Human mitochondrial tRNA genes are hotspots for pathogenic mutations and have attracted interest over the last two decades with the rapid discovery of point mutations associated with a vast array of neuromuscular disorders and diverse clinical phenotypes. In this review, we use a scoring system to determine the pathogenicity of the mutations and summarize the current knowledge of structure–function relationships of these mutant tRNAs. We also provide readers with an overview of a large variety of mechanisms by which mutations may affect the mitochondrial translation machinery and cause disease. Muscle Nerve, 2007
Bottomhole assembly analysis by finite difference differential method
Authors: Yang Dongquan , Rahman M. K. , Chen Yibai
Published: November 2007

This paper presents a three‐dimensional finite difference differential method for bottomhole assembly (BHA) analysis under static loads. The analysis is required to optimize the BHA configurations for drilling directional boreholes in the petroleum industry. The optimization of BHA configurations ensures the controlled cruising of the drill bit to drill the hole along a planned trajectory. The model incorporates the contact response between drillstring and wellbore wall, the upper tangent point problem, stabilizer configurations, bent sub model and other considerations for numerical solutions. The overall formulations are presented in a matrix format within convenient coordinate systems developing a transformation matrix. Key solution algorithms for computer programming are then described in detail. One analytical solution for beams under weight and torque is used to verify the method. Also the analytical solutions of three other simple BHA configurations are used for verification. The verified method is then applied in a series of parametric investigations to characterize the responses of typical BHAs. The BHA responses studied include the side force at bit and lateral deformation of the assembly along its length with varying weights on bit and hole inclination angles for typical building, dropping and holding assemblies. BHAs with bent sub are analyzed with various tool face angles and bent angles. The effect of wellbore curvature on side forces is also demonstrated. Copyright © 2007 John Wiley & Sons, Ltd.
On the computation of nearly singular integrals in 3D BEM collocation
Authors: Scuderi Letizia
Published: November 2007

In this paper, we propose an efficient strategy to compute nearly singular integrals over planar triangles in R3 arising in boundary element method collocation. The strategy is based on a proper use of various non‐linear transformations, which smooth or move away or quite eliminate all the singularities close to the domain of integration. We will deal with near singularities of the form 1/r, 1/r2 and 1/r3, r=∥x−y∥ being the distance between a fixed near observation point x and a generic point y of a triangular element. Extensive numerical tests and comparisons with some already existing methods show that the approach proposed here is highly efficient and competitive. Copyright © 2007 John Wiley & Sons, Ltd.
A boundary meshless method using Chebyshev interpolation and trigonometric basis function for solving heat conduction problems
Authors: Reutskiy S. Yu. , Chen C. S. , Tian H. Y.
Published: November 2007

A boundary meshless method has been developed to solve the heat conduction equations through the use of a newly established two‐stage approximation scheme and a trigonometric series expansion scheme to approximate the particular solution and fundamental solution, respectively. As a result, no fundamental solution is required and the closed form of approximate particular solution is easy to obtain. The effectiveness of the proposed computational scheme is demonstrated by several examples in 2D and 3D. We also compare our proposed method with the finite‐difference method and the other meshless method showed in Šarler and Vertnik (Comput. Math. Appl. 2006; 51:1269–1282). Excellent numerical results have been observed. Copyright © 2007 John Wiley & Sons, Ltd.
Assumed strain finite element methods for conserving temporal integrations in non‐linear solid dynamics
Authors: Armero F.
Published: November 2007

This paper presents a new class of assumed strain finite elements to use in combination with general energy‐momentum‐conserving time‐stepping algorithms so that these conservation properties in time are preserved by the fully discretized system in space and time. The case of interest corresponds to nearly incompressible material responses, in the fully non‐linear finite strain elastic and elastoplastic ranges. The new elements consider the classical scaling of the deformation gradient with an assumed Jacobian (its determinant) defined locally through a weighted averaging procedure at the element level. The key aspect of the newly proposed formulation is the definition of the associated linearized strain operator or B‐bar operator. The developments presented here start by identifying the conditions that this discrete operator must satisfy for the fully discrete system in time and space to inherit exactly the conservation laws of linear and angular momenta, and the conservation/dissipation law of energy for elastic and inelastic problems, respectively. Care is also taken of the preservation of the relative equilibria and the corresponding group motions associated with the momentum conservation laws, and characterized by purely rotational and translational motions superimposed to the equilibrium deformed configuration. With these developments at hand, a new general B‐bar operator is introduced that satisfies these conditions. The new operator not only accounts for the spatial interpolations (e.g. bilinear displacements with piece‐wise constant volume) but also depends on the discrete structure of the equations in time. The aforementioned conservation/dissipation properties of energy and momenta are then proven to hold rigorously for the final numerical schemes, unconditionally of the time step size and the material model (elastic or elastoplastic). Different finite elements are considered in this framework, including quadrilateral and triangular elements for plane problems and brick elements for three‐dimensional problems. Several representative numerical simulations are presented involving, in particular, the use of energy‐dissipating momentum‐conserving time‐stepping schemes recently developed by the author and co‐workers for general finite strain elastoplasticity in order to illustrate the properties of the new finite elements, including these conservation/dissipation properties in time and their locking‐free response in the quasi‐incompressible case. Copyright © 2007 John Wiley & Sons, Ltd.
Utility of microsatellite analysis in evaluation of pregnancies with placental mesenchymal dysplasia
Authors: Schuetzle Marie N. , Uphoff Timothy S. , Hatten Bonnie A. , Dawson D. Brian
Published: November 2007

Objective

To demonstrate a role for microsatellite analysis in the evaluation of prenatal cases with possible placental mesenchymal dysplasia (PMD).

Methods

We present a case report in which several molecular analyses of amniocytes and products of conception were used in combination with cytogenetic and ultrasound studies to evaluate a pregnancy with a clinical suspicion of PMD. A combination of Southern blotting analysis, methylation‐sensitive polymerase chain reaction (PCR) and multiplex ligation‐dependent probe amplification (MLPA) was utilized to evaluate methylation patterns in the Beckwith–Wiedemann syndrome (BWS) and Prader–Willi/Angelman syndrome (PW/AS) critical regions. A series of microsatellite markers were used to evaluate the possibility of an androgenetic cell line.

Results

Methylation studies performed for the BWS and PW/AS critical regions were abnormal and consistent with a molecular diagnosis of BWS and Angelman syndrome. Further studies of amniocytes using microsatellite markers identified androgenetic and biparental cell lines in approximately a 10:1 ratio, respectively.

Conclusions

Prenatal ultrasonography, karyotyping and molecular genetic evaluation for BWS alone were not sufficient to identify the underlying etiology of PMD in this case. The androgenetic cell line was only identified after microsatellite analysis. Copyright © 2007 John Wiley & Sons, Ltd.