bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural Model of Radiolocation Signal Patterns Extractor
Authors: Krukar Wojciech , Niedziela Tadeusz
Published: March 2009

Neural Model of Radiolocation Signal Patterns Extractor

Simulation researches have been conducted of programmable neural extractor model which realizes object detection and determines its position on the background of noise. For the simulation of radiolocation signal the model of signal has been used which is a sum of two independent processes, namely signal reflected from an object, and noise. This model takes into account impulse sounding, radiation characteristics of rotating aerial, fluctuation of echoing area of an object, and Doppler shift of carrier frequency. For comparative researches, models of superficial and superficial-amplitude extractors have been adopted. As a result of experience gathered during project work, the best network structure for the tasks given to neural extractor appeared to be a three-layer network trained by means of back propagation, having two hidden layers with tangensoidal activation function and a moveable threshold.
Portable Airfield Surfaces
Authors: Wesołowski Mariusz
Published: March 2009

Portable Airfield Surfaces

Since existing methods and technologies for rebuilding airfield surfaces damaged in unfortunate events can not cope with stringent time regimes, folding, portable airfield surfaces have been constructed. NATO member countries, including Poland, have at their disposal portable airfield surfaces which allow the restoration of damaged airfield surface system components in the shortest time possible. Currently, for repairing damage to major airfield surfaces two types of folding, portable airfield surfaces are used: aluminium and composite, both assuring safe conditions for airborne operations.
Metody FDM-A i FAM-C W Wykrywaniu I Monitorowaniu Silnie Zaciśniętych Łożysk Tocznych
Authors: Gębura Andrzej , Tokarski Tomasz
Published: March 2009

Metody FDM-A i FAM-C W Wykrywaniu I Monitorowaniu Silnie Zaciśniętych Łożysk Tocznych

W artykule przedstawiono badania eksploatacyjne z zastosowaniem metod diagnostycznych opartych na wykorzystaniu analizy modulacji częstotliwości prądnic FDM-A i FAM-C. Metod tych użyto do wykrywania i monitorowania ruchu zbyt silnie zaciśniętych łożysk tocznych w węzłach łożyskowych silników turboodrzutowych. Szczególną uwagę poświęcono obserwacji ruchu tocznego poszczególnych elementów tocznych oraz płynności ruchu koszyka. W wyniku wykonanych badań i diagnoz stwierdzono, że z chwilą powstania zbyt silnego zacisku pierwszym i najważniejszym skutkiem, obserwowanym metodą FDM-A, jest względne zróżnicowanie stochastyczne płynności ruchu poszczególnych elementów tocznych. W wymienionej metodzie zjawisko to obserwowane jest jako niestabilność szerokości pasma zbioru charakterystycznego danego łożyska tocznego.
Radio-Isotope Identification Algorithms for NaI γ Spectra
Authors: Burr Tom , Hamada Michael
Published: March 2009

The performance of Radio-Isotope Identification (RIID) algorithms using NaI-based γ spectroscopy is increasingly important. For example, sensors at locations that screen for illicit nuclear material rely on isotope identification using NaI detectors to distinguish innocent nuisance alarms, arising from naturally occurring radioactive material, from alarms arising from threat isotopes. Recent data collections for RIID testing consist of repeat measurements for each of several measurement scenarios to test RIID algorithms. It is anticipated that vendors can modify their algorithms on the basis of performance on chosen measurement scenarios and then test modified algorithms on data for other measurement scenarios. It is therefore timely to review the current status of RIID algorithms on NaI detectors. This review describes γ spectra from NaI detectors, measurement issues and challenges, current RIID algorithms, data preprocessing steps, the role and current quality of synthetic spectra, and opportunities for improvements.
Flavonoids with Gastroprotective Activity
Authors: De Lira Mota Kelly Samara , Dias Guilherme Eduardo Nunes , Pinto Meri Emili Ferreira , Luiz-Ferreira Ânderson , Monteiro Souza-Brito Alba Regina , Hiruma-Lima Clélia Akiko , Barbosa-Filho José Maria , Batista Leônia Maria
Published: March 2009

Peptic ulcers are a common disorder of the entire gastrointestinal tract that occurs mainly in the stomach and the proximal duodenum. This disease is multifactorial and its treatment faces great difficulties due to the limited effectiveness and severe side effects of the currently available drugs. The use of natural products for the prevention and treatment of different pathologies is continuously expanding throughout the world. This is particularly true with regards to flavonoids, which represent a highly diverse class of secondary metabolites with potentially beneficial human health effects that is widely distributed in the plant kingdom and currently consumed in large amounts in the diet. They display several pharmacological properties in the gastroprotective area, acting as anti-secretory, cytoprotective and antioxidant agents. Besides their action as gastroprotectives, flavonoids also act in healing of gastric ulcers and additionally these polyphenolic compounds can be new alternatives for suppression or modulation of peptic ulcers associated with H. pylori. In this review, we have summarized the literature on ninety-five flavonoids with varying degrees of antiulcerogenic activity, confirming that flavonoids have a therapeutic potential for the more effective treatment of peptic ulcers.
Automated Directional Measurement System for the Acquisition of Thermal Radiative Measurements of Vegetative Canopies
Authors: Timmermans Joris , Ambro Gieske A.S.M. , Van der Tol Christiaan , Verhoef Wout , Su Zhongbo
Published: March 2009

The potential for directional optical and thermal imagery is very large. Field measurements have been performed with a goniometer on which thermal instruments were attached. In order to reduce dynamical effects the goniometer was adjusted to run in automated mode, for zenith and azimuthal direction. Directional measurements were performed over various crops with increasing heterogeneity. The improvements to the goniometer proved successful. For all the crops, except the vineyard, the acquisition of the directional thermal brightness temperatures of the crops went successfully. The large scale heterogeneity of the vineyard proved to be larger then the goniometer was capable of. The potential of directional thermal brightness temperatures has been proven.
Real Time Monitoring of Temperature of a Micro Proton Exchange Membrane Fuel Cell
Authors: Lee Chi-Yuan , Lee Shuo-Jen , Hu Yuh-Chung , Shih Wen-Pin , Fan Wei-Yuan , Chuang Chih-Wei
Published: March 2009

Silicon micro-hole arrays (Si-MHA) were fabricated as a gas diffusion layer (GDL) in a micro fuel cell using the micro-electro-mechanical-systems (MEMS) fabrication technique. The resistance temperature detector (RTD) sensor was integrated with the GDL on a bipolar plate to measure the temperature inside the fuel cell. Experimental results demonstrate that temperature was generally linearly related to resistance and that accuracy and sensitivity were within 0.5 °C and 1.68×10-3/°C, respectively. The best experimental performance was 9.37 mW/cm2 at an H2/O2 dry gas flow rate of 30/30 SCCM. Fuel cell temperature during operation was 27 °C, as measured using thermocouples in contact with the backside of the electrode. Fuel cell operating temperature measured in situ was 30.5 °C.
Early Forest Fire Detection Using Radio-Acoustic Sounding System
Authors: Sahin Yasar Guneri , Ince Turker
Published: March 2009

Automated early fire detection systems have recently received a significant amount of attention due to their importance in protecting the global environment. Some emergent technologies such as ground-based, satellite-based remote sensing and distributed sensor networks systems have been used to detect forest fires in the early stages. In this study, a radio-acoustic sounding system with fine space and time resolution capabilities for continuous monitoring and early detection of forest fires is proposed. Simulations show that remote thermal mapping of a particular forest region by the proposed system could be a potential solution to the problem of early detection of forest fires.
Preliminary genome‐wide association study of bipolar disorder in the Japanese population
Authors: Hattori Eiji , Toyota Tomoko , Ishitsuka Yuichi , Iwayama Yoshimi , Yamada Kazuo , Ujike Hiroshi , Morita Yukitaka , Kodama Masafumi , Nakata Kenji , Minabe Yoshio , Nakamura Kazuhiko , Iwata Yasuhide , Takei Nori , Mori Norio , Naitoh Hiroshi , Yamanouchi Yoshio , Iwata Nakao , Ozaki Norio , Kato Tadafumi , Nishikawa Toru , Kashiwa Atsushi , Suzuki Mika , Shioe Kunihiko , Shinohara Manabu , Hirano Masami , Nanko Shinichiro , Akahane Akihisa , Ueno Mikako , Kaneko Naoshi , Watanabe Yuichiro , Someya Toshiyuki , Hashimoto Kenji , Iyo Masaomi , Itokawa Masanari , Arai Makoto , Nankai Masahiro , Inada Toshiya , Yoshida Sumiko , Kunugi Hiroshi , Nakamura Michiko , Iijima Yoshimi , Okazaki Yuji , Higuchi Teruhiko , Yoshikawa Takeo
Published: March 2009

Recent progress in genotyping technology and the development of public databases has enabled large‐scale genome‐wide association tests with diseases. We performed a two‐stage genome‐wide association study (GWAS) of bipolar disorder (BD) in Japanese cohorts. First we used Affymetrix 100K GeneChip arrays in the analysis of 107 cases with bipolar I disorder and 107 controls, and selected markers that were nominally significant (P < 0.01) in at least one of the three models (1,577 markers in total). In the follow‐up stage, we analyzed these markers using an Illumina platform (1,526 markers; 51 markers were not designable for the platform) and an independent sample set, which consisted of 395 cases (bipolar I + II) and 409 controls. We also assessed the population stratification of current samples using principal components analysis. After the two‐stage analysis, 89 markers remained nominally significant (allelic P < 0.05) with the same allele being consistently over‐represented in both the first and the follow‐up stages. However, none of these were significant after correction for multiple‐testing by false discovery rates. Sample stratification was virtually negligible. Collectively, this is the first GWAS of BD in the Japanese population. But given the small sample size and the limited genomic coverage, these results should be taken as preliminary. © 2009 Wiley‐Liss, Inc.
β2‐adrenoceptors are critical for antidepressant treatment of neuropathic pain
Authors: Yalcin Ipek , Choucair‐Jaafar Nada , Benbouzid Malika , Tessier Luc‐Henri , Muller André , Hein Lutz , Freund‐Mercier Marie‐José , Barrot Michel
Published: March 2009

Objective

Tricyclic antidepressants (TCAs) are one of the first‐line pharmacological treatments against neuropathic pain. TCAs increase the extracellular concentrations of noradrenaline and serotonin by blocking the reuptake transporters of these amines. However, the precise downstream mechanism leading to the therapeutic action remains identified. In this work, we evaluated the role of adrenergic receptors (ARs) in the action of TCAs.

Methods

We used pharmacological and genetic approaches in mice to study the role of ARs in the antiallodynic action of the TCA nortriptyline. Peripheral neuropathy was induced by the insertion of a polyethylene cuff around the main branch of the sciatic nerve. The specific role of β2‐AR was evaluated by studying β2‐AR−/− mice. We used von Frey filaments to assess mechanical allodynia.

Results

The antiallodynic action of nortriptyline was not affected by cotreatment with the α2‐AR antagonist yohimbine, the β1‐AR antagonists atenolol or metoprolol, or the β3‐AR antagonist SR 59230A. On the contrary, the β‐AR antagonists propranolol or sotalol, the β1/β2‐AR antagonists alprenolol or pindolol, or the specific β2‐AR antagonist ICI 118,551 blocked the action of nortriptyline. The effect of nortriptyline was also totally absent in β2‐AR–deficient mice.

Interpretation

Stimulation of β2‐AR is necessary for nortriptyline to exert its antiallodynic action against neuropathic pain. These findings provide new insight into the mechanism by which antidepressants alleviate neuropathic pain. Our results also raise the question of a potential incompatibility between β‐blockers that affect β2‐AR and antidepressant drugs in patients treated for neuropathic pain. Ann Neurol 2009;65:218–225
Systems biology and its application to the understanding of neurological diseases
Authors: Villoslada Pablo , Steinman Lawrence , Baranzini Sergio E.
Published: March 2009

Recent advances in molecular biology, neurobiology, genetics, and imaging have demonstrated important insights about the nature of neurological diseases. However, a comprehensive understanding of their pathogenesis is still lacking. Although reductionism has been successful in enumerating and characterizing the components of most living organisms, it has failed to generate knowledge on how these components interact in complex arrangements to allow and sustain two of the most fundamental properties of the organism as a whole: its fitness, also termed its robustness, and its capacity to evolve. Systems biology complements the classic reductionist approaches in the biomedical sciences by enabling integration of available molecular, physiological, and clinical information in the context of a quantitative framework typically used by engineers. Systems biology employs tools developed in physics and mathematics such as nonlinear dynamics, control theory, and modeling of dynamic systems. The main goal of a systems approach to biology is to solve questions related to the complexity of living systems such as the brain, which cannot be reconciled solely with the currently available tools of molecular biology and genomics. As an example of the utility of this systems biological approach, network‐based analyses of genes involved in hereditary ataxias have demonstrated a set of pathways related to RNA splicing, a novel pathogenic mechanism for these diseases. Network‐based analysis is also challenging the current nosology of neurological diseases. This new knowledge will contribute to the development of patient‐specific therapeutic approaches, bringing the paradigm of personalized medicine one step closer to reality. Ann Neurol 2009;65:124–139
Telomerisation – Fortschritte und Anwendungen einer vielseitigen Reaktion
Authors: Behr Arno , Becker Marc , Beckmann Thomas , Johnen Leif , Leschinski Julia , Reyer Sebastian
Published: March 2009

Wandelbar wie ein Chamäleon: Die übergangsmetallkatalysierte Telomerisation von 1,3‐Dienen mit verschiedenen Nucleophilen führt zur zahlreichen Produkten, die sowohl in Kosmetika und Pharmaka als auch in Polymeren und Duftstoffen Anwendung finden. Der Aufsatz gibt einen Überblick über diese vielseitige Reaktion mit Bezug auf die aktuelle Forschung und industrielle Anwendungen.

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Durch übergangsmetallkatalysierte Telomerisation von 1,3‐Dienen mit verschiedenen Nucleophilen lassen sich zahlreiche funktionalisierte Kohlenwasserstoffe synthetisieren, z. B. Zuckerether, substituierte Lactone oder Terpenderivate, die in Kosmetika und pharmazeutischen Produkten sowie in Polymeren und Aromastoffen Anwendung finden. Die Reaktion kann durch die Wahl des Katalysatorsystems, der Reaktanten und der Reaktionsbedingungen gesteuert werden. Seit der Entdeckung der Telomerisation im Jahr 1967 gab es viele Ansätze zur Nutzung der Reaktion. In diesem Aufsatz wird anhand von Beispielen aus Forschung und Industrie die Vielseitigkeit dieser Reaktion verdeutlicht, wobei besonders auf Katalysator‐ und Prozessentwicklungen sowie ausgewählte mechanistische Aspekte eingegangen wird.
Helicale Anordnung von Porphyrinen entlang der DNA: auf dem Weg zu DNA‐Nanoarchitekturen
Authors: Wagenknecht Hans‐Achim
Published: March 2009

Staple sie helical: Ein selbstorganisierter, helicaler Stapel von bis zu elf mit zwei unterschiedlichen Porphyrin(Po)‐Einheiten (blau und rot im gezeigten Doppelstrang) modifizierten Uridinresten beruht auf dem supramolekularen Strukturgerüst doppelsträngiger DNA und zeigt vielversprechende optische Eigenschaften. Solche Architekturen könnten Anwendung als funktionelle Moleküle für photoaktive Nanomaterialien und photonische Nanostrukturen finden.

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Unprecedented Selectivity via Electronic Substrate Recognition in the 1,4‐Addition to Cyclic Olefins Using a Chiral Disulfoxide Rhodium Catalyst
Authors: Bürgi Justus J. , Mariz Ronaldo , Gatti Michele , Drinkel Emma , Luan Xinjun , Blumentritt Sascha , Linden Anthony , Dorta Reto
Published: March 2009

Und es geht doch: Sulfoxide galten bisher als wenig nützliche Liganden für die asymmetrische Metallkatalyse. Ein chiraler Disulfoxid‐Chelatligand wurde nun gefunden, der bei der Rh‐katalysierten 1,4‐Addition von Arylboronsäuren an cyclische α,β‐ungesättigte Ketone und Ester hervorragende Ergebnisse liefert und so den Weg für zukünftige Anwendungen dieser neuen chiralen Ligandenklasse ebnet.

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Helical Arrangement of Porphyrins along DNA: Towards Photoactive DNA‐Based Nanoarchitectures
Authors: Wagenknecht Hans‐Achim
Published: March 2009

Stack them helically: A self‐assembled helically stacked array of up to 11 porphyrin (Po)‐modified uridines (red and blue in the double strand shown) is based on the supramolecular scaffold of duplex DNA and shows promising optical properties. Such architectures could find application as functional molecules for photoactive nanomaterials and photonic nanostructures.

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Inside Cover: Bifunctional Dendrimers: From Robust Synthesis and Accelerated One‐Pot Postfunctionalization Strategy to Potential Applications (Angew. Chem. Int. Ed. 12/2009)
Authors: Antoni Per , Hed Yvonne , Nordberg Axel , Nyström Daniel , von Holst Hans , Hult Anders , Malkoch Michael
Published: March 2009

By taking advantage of “click” chemistry's chemoselective nature, a new platform of bifunctional AB2C dendrimers, having acetylene/azide groups anchored within the interior and hydroxy groups on the periphery, has been realized. In their Communication on page 2126 ff. M. Malkoch and co‐workers reveal a simple synthetic route for two sets of frameworks. To illustrate the utility of AB2C dendrimers they were used in a one‐pot postfunctionalization protocol, in the development of dendritic nanoparticles, and in the formation of hydrogels.

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Polypropylene/natural rubber thermoplastic elastomer: Effect of phenolic resin as a vulcanizing agent on mechanical properties and morphology
Authors: Tanrattanakul Varaporn , Kosonmetee Kesinee , Laokijcharoen Pasaree
Published: March 2009

The aim of this study is to characterize thermoplastic elastomers (TPEs) from polypropylene and natural rubber with and without phenolic resin as a vulcanizing agent. The blends containing 40–60 wt % of polypropylene were mixed in an internal mixer and pressed with a compression molding machine. TPEs without rubber vulcanization, named as unvulcanized thermoplastic natural rubber (uTPNR) were compared to TPEs containing dynamic vulcanized rubber, referred as vulcanized thermoplastic natural rubber (vTPNR). The uTPNRs illustrated cocontinuous phase morphology, whereas the vTPNRs displayed dispersed phase of vulcanized natural rubber. Tensile properties, tear strength, thermal ageing resistance, ozone resistance, tension set, hardness and swelling test in toluene, IRM 903 oil and engine oil were carried out according to ASTM. It was found that tensile and tear strength, hardness and tension set of the uTPNRs increased with increasing polypropylene content. Dynamic vulcanization improved tensile strength, elongation at break, tension set and degree of swelling of the TPEs, whereas hardness and tear strength did not show significant change after dynamic vulcanization. The vTPNRs exhibited higher ozone resistance and swelling resistance than the uTPNRs. Reprocessability of the vTPNRs was investigated and showed that tensile strength decreased at 20 and 30% and elongation at break decreased at 13 and 27% for the first and the third reprocessing respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
How effective is geophysical survey? A regional review
Authors: Jordan David
Published: March 2009

Geophysics is such an accepted part of British archaeology that its effectiveness seems obvious. Yet if there is no reason to doubt the benefits of geophysics why do some experienced archaeologists use it so rarely and why is it little used in some countries which, in other ways, have highly developed professional archaeology services? There are, often cheaper, alternatives for archaeological survey. Yet since the performance of different survey methods has rarely been studied systematically there is no objective basis on which to test which choices best meet archaeologists' needs. Moreover the geophysicists' understandable desire to present successful rather than unsuccessful surveys, and to discuss results in geophysical rather than archaeological terms, makes such assessment more difficult. Thus although geophysical surveyors have strong grounds to claim that their work benefits archaeology, those who pay for survey can reasonably ask that these benefits be clarified, quantified where possible, and compared with alternatives, such as aerial photography or surface artefact survey, so that they can make the best choices about its use.

This paper summarizes a study of all the geophysical surveys carried out in the northwest of England before 2006. The study assessed the performance of geophysical surveys in archaeological terms and was centred on a detailed analysis of 35 sites for which there is good comparative excavation data or which have particularly illustrative case histories. The study concludes that, despite the doubts in this area, geophysics serves archaeologists well and provides greater certainty in both identifying where sites exist and where they do not exist than has been generally assumed. It therefore deserves more extensive and more rational use. Geophysics is, however, being underused because, although abundant, surveys are formulaic and commercial surveyors are rarely able to fit methodologies to sites by a programme of reflective project development. Thus, although currently effective, geophysics might be even more so if surveyors had the time and resources to do this and to answer more complex and specific questions. The paper considers how these findings relate to the use of geophysical survey in other countries. Copyright © 2009 John Wiley & Sons, Ltd.
Evaluating the multiple coil configurations of the EM38DD and DUALEM‐21S sensors to detect archaeological anomalies
Authors: Simpson David , Van Meirvenne Marc , Saey Timothy , Vermeersch Hans , Bourgeois Jean , Lehouck Alexander , Cockx Liesbet , Vitharana Udayakantha W. A.
Published: March 2009

The multiple coil configurations of two electromagnetic induction sensors were tested on a field with strong electrical and magnetic contrasts. The first sensor, EM38DD, measures either the apparent electrical conductivity (ECa or σa) or the apparent magnetic susceptibility (MSa or χa) of the soil at two coil orientations. The second sensor, DUALEM‐21S, measures both ECa and MSa at two coil orientations and two coil separations. The goal was to test if measuring with the multiple coils resulted in a better detection of near‐surface artefacts and the natural soil variability. The ECa of all coil configurations was closely related to the depth of a clay substrate beneath the topsoil sandy loam, which was verified by soil augering. Configurations with a shallower theoretical depth of exploration were less influenced by the clay substrate. Combining two coil configurations revealed important ECa anomalies, not visible on individual measurements, associated with a brick wall foundation and a former ditch. The MSa maps showed totally different anomaly patterns, related to anthropogenic disturbances in the soil, such as the filling‐in with brick rubble of a former pond. Depending on the depth and thickness of the disturbance and the relative response of the sensor configurations, the MSa anomalies were entirely positive for one configuration but other configurations also had negative anomalies. It was concluded that multiple coil configurations provide a better insight into the build‐up of the soil profile and are better able to detect anomalies than single measurements. Copyright © 2009 John Wiley & Sons, Ltd.
Blood laboratory findings in patients suffering from self‐perceived electromagnetic hypersensitivity (EHS)
Authors: Dahmen Norbert , Ghezel‐Ahmadi David , Engel Alice
Published: March 2009

Risks from electromagnetic devices are of considerable concern. Electrohypersensitive (EHS) persons attribute a variety of rather unspecific symptoms to exposure to electromagnetic fields. The pathophysiology of EHS is unknown and therapy remains a challenge. We hypothesized that some electrosensitive individuals are suffering from common somatic health problems. Toward this end we analysed clinical laboratory parameters including thyroid‐stimulating hormone (TSH), alanine transaminase (ALT), aspartate transaminase (AST), creatinine, hemoglobine, hematocrit and c‐reactive protein (CRP) in subjects suffering from EHS and in controls that are routinely used in clinical medicine to identify or screen for common somatic disorders. One hundred thirty‐two patients (n = 42 males and n = 90 females) and 101 controls (n = 34 males and n = 67 females) were recruited. Our results identified laboratory signs of thyroid dysfunction, liver dysfunction and chronic inflammatory processes in small but remarkable fractions of EHS sufferers as potential sources of symptoms that merit further investigation in future studies. In the cases of TSH and ALT/AST there were significant differences between cases and controls. The hypotheses of anaemia or kidney dysfunction playing a major role in EHS could be unambiguously refuted. Clinically it is recommended to check for signs of treatable somatic conditions when caring for individuals suffering from self‐proclaimed EHS. Bioelectromagnetics 30:299–306, 2009. © 2009 Wiley‐Liss, Inc.
Generating, growing and transforming skeletal shape: insights from amphibian pharyngeal arch cartilages
Authors: Rose Christopher
Published: March 2009

Amphibians that undergo a metamorphosis provide an unparalleled opportunity to investigate how skeletal shape is generated, preserved, and transformed in development. Their pharyngeal arch (PA) cartilages, which support breathing and feeding behaviors, form embryonically from cranial neural crest cells, grow isometrically at larval stages, and abruptly change shape during metamorphosis. Further, the shape changes occur in three different ways: some adult cartilages form de novo, others emerge from within resorbing larval cartilages and some larval cartilages reshape themselves at the cellular level. Isometric growth followed by abrupt shape change is unique to amphibian PA cartilages, which suggests that the origin and evolution of amphibian metamorphosis has been influenced by the tissue properties of cartilage. This essay reviews the functional role of the PA skeleton in frogs and salamanders and presents a mechanistic framework for understanding how its shape is generated, preserved, and transformed at the levels of cell behavior and specification mechanisms.
Close encounters of the third kind: disordered domains and the interactions of proteins
Authors: Tompa Peter , Fuxreiter Monika , Oldfield Christopher J. , Simon Istvan , Dunker A. Keith , Uversky Vladimir N.
Published: March 2009

Protein–protein interactions are thought to be mediated by domains, which are autonomous folding units of proteins. Recently, a second type of interaction has been suggested, mediated by short segments termed linear motifs, which are related to recognition elements of intrinsically disordered regions. Here, we propose a third kind of protein–protein recognition mechanism, mediated by disordered regions longer than 20–30 residues. Bioinformatics predictions and well‐characterized examples, such as the kinase‐inhibitory domain of Cdk inhibitors and the Wiskott–Aldrich syndrome protein (WASP)‐homology domain 2 of actin‐binding proteins, show that these disordered regions conform to the definition of domains rather than motifs, i.e., they represent functional, evolutionary, and structural units. Their functions are distinct from those of short motifs and ordered domains, and establish a third kind of interaction principle. With these points, we argue that these long disordered regions should be recognized as a distinct class of biologically functional protein domains.
Chromatin loops, illegitimate recombination, and genome evolution
Authors: Kantidze Omar L. , Razin Sergey V.
Published: March 2009

Chromosomal rearrangements frequently occur at specific places (“hot spots”) in the genome. These recombination hot spots are usually separated by 50–100 kb regions of DNA that are rarely involved in rearrangements. It is quite likely that there is a correlation between the above‐mentioned distances and the average size of DNA loops fixed at the nuclear matrix. Recent studies have demonstrated that DNA loop anchorage regions can be fairly long and can harbor DNA recombination hot spots. We previously proposed that chromosomal DNA loops may constitute the basic units of genome organization in higher eukaryotes. In this review, we consider recombination between DNA loop anchorage regions as a possible source of genome evolution.
A tale of tails: insights into the coordination of 3′ end processing during homologous recombination
Authors: Lyndaker Amy M. , Alani Eric
Published: March 2009

Eukaryotic genomes harbor a large number of homologous repeat sequences that are capable of recombining. Their potential to disrupt genome stability highlights the need to understand how homologous recombination processes are coordinated. The Saccharomyces cerevisiae Rad1–Rad10 endonuclease performs an essential role in recombination between repeated sequences, by processing 3′ single‐stranded intermediates formed during single‐strand annealing and gene conversion events. Several recent studies have focused on factors involved in Rad1–Rad10‐dependent removal of 3′ nonhomologous tails during homologous recombination, including Msh2–Msh3, Slx4, and the newly identified Saw1 protein. Together, this new work provides a model for how Rad1–Rad10‐dependent end processing is coordinated: Msh2–Msh3 stabilizes and prepares double‐strand/single‐strand junctions for Rad1–Rad10 cleavage, Saw1 recruits Rad1–Rad10 to 3′ tails, and Slx4 mediates crosstalk between the DNA damage checkpoint machinery and Rad1–Rad10.
BioEssays 3/2009
Authors: Tompa Peter , Fuxreiter Monika , Oldfield Christopher J. , Simon Istvan , Dunker A. Keith , Uversky Vladimir N.
Published: March 2009

Cover Photograph: Structure of the actin‐regulatory protein thymosin‐beta4 (gold) in complex with G‐actin (grey). The amino acid sequence corresponding to thymosin beta4 also appears as part of other proteins, when it is termed the WH2 domain. The domain, as also suggested by its extended conformation in the complex, is intrinsically disordered in isolation. Such examples call upon the extension of the domain concept of proteins, as discussed in the article by Tompa et al. (on pages 328‐335).
The “safe zone” in medial percutaneous calcaneal pin placement
Authors: Gamie Zakareya , Donnelly Leo , Tsiridis Eleftherios
Published: March 2009

Percutaneous pin insertion into the medial calcaneus places a number of structures at risk. Evidence suggests that the greatest risk is to the medial calcaneal nerve (MCN). The medial calcaneal region of 24 cadavers was dissected to determine the major structures at risk. By using four palpable anatomical landmarks, the inferior tip of the medial malleolus (point A), the posterior superior portion of the calcaneal tuberosity (point B), the navicular tuberosity (point C), and the medial process of the calcaneal tuberosity (point D), we attempted to define the safe zone taking into account all possible variables in our dissections including ankle position, side, gender, and possible anatomical variations of the MCN. The commonest arrangement of the MCN was two MCNs that arose independently, one arising before the bifurcation of the tibial nerve and the other arising from the medial plantar nerve. A zone could be defined posterior to 75% of the distance along the lines AB, CD, AD, and CB which would avoid most structures. The posterior branches of the MCN, however, would still be at risk and placing the pin too far posteriorly risks an avulsion fracture. This is the first study to employ four palpable anatomical landmarks to identify a zone to minimize damage to neurovascular structures. It may not be possible, however, to avoid injury of the MCN and consequent sensory loss to the sole of the foot. foot. Clin. Anat. 22:523–529, 2009. © 2009 Wiley‐Liss, Inc.
Origin of the radial nerve branch innervating the brachialis muscle
Authors: Oh Chang‐Seok , Won Hyung‐Sun , Lee Kyu‐Seok , Chung In‐Hyuk
Published: March 2009

The brachialis muscle is dually innervated by the musculocutaneous nerve running via the anterior division of the brachial plexus and the radial nerve running via the posterior division of the plexus. There have been inconsistent descriptions of the pathway of the radial nerve branch at the brachial plexus. This study investigated the route of the radial nerve branch innervating the brachialis muscle at the brachial plexus. In 20 samples, the radial nerve branch innervating the brachialis muscle was separated and traced up to the cervical nerve under a surgical microscope. All the radial nerve branches innervating the muscle ran via the posterior cord, the posterior division, and the superior or middle trunk at the brachial plexus. The radial nerve branches arose from C5 in 5 cases, C6 in 11 cases, C5 and C6 in 3 cases, and C6 and C7 in 1 case. Clin. Anat. 22:495–499, 2009. © 2009 Wiley‐Liss, Inc.
A web‐based training framework in automotive electric education
Authors: Liang Janus S.
Published: March 2009

In this study, the mechanism of network information is applied together with CAD, open software and virtual reality technology to generate a web‐based learning framework for measuring components and circuit design of automobile electric system. Different from traditional teaching methods, this web‐based system is very helpful for students to learn skills of measurements and circuit design. There are three topics discussed in this study: (1) developing the learning module for measuring electric parts; (2) building the platform for practice of electric circuit; (3) creating the online study tools and effectiveness analysis. The effectiveness of this training system was tested after experiment instruction. Close to 100% attendance was observed during the practice sessions, which demonstrates the success in generating interest among the students. The training platform developed through this study was tested capable of improving learning efficiency on technology content and promoting students' ability of troubleshooting on automotive electrical system. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 619–633, 2010; View this article online atwileyonlinelibrary.com; DOI 10.1002/cae.20257
Teaching and learning enhancement in undergraduate machine dynamics
Authors: Aziz El‐Sayed
Published: March 2009

Currently, information technology (IT) is playing a significant role in the development of learning environments. The integration of IT into the classroom provides innovative learning environments that allow for more interactive, relevant, and effective applications to give students valuable experiences. This article presents the design and implementation of more active and collaborative methods of teaching and learning in a course on mechanisms and machine dynamics. Through the use of virtual collaborative environments such as cooperative learning, problem‐based learning (PBL), critical thinking, and more in the context of IT‐enabled environments, students are given the opportunity to experiment with ideas and see the results of their efforts on the computer screen. These interactive learning modules impose more responsibility on students for their own learning than the traditional lecture‐based passive learning methodology. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 244–255, 2011
Bridging the gap between textbook and real applications: A teaching methodology in digital electronics education
Authors: Wang Guoping
Published: March 2009

This paper describes a teaching methodology in digital electronics education. Its purpose is to bridge the gap between traditional textbooks using out‐of‐date discrete 74‐series TTL chips and the current industry in which FPGA components and EDA design tools are becoming the standard. The principles and practices of digital components are presented to the students from five aspects, that is, classroom lecture, Multisim homework assignments, breadboard lab practices, Xilinx ISE computer design and simulation, and FPGA board verification. This approach is expected to help students better prepare for the current trends of digital systems design while not sacrificing the basic theories and principles. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 268–279, 2011
Effect of S Replacement on the Mechanism of Unimolecular Reactions for Ground‐state Thioacetic Acid: A Theoretical Study
Authors: LU Aimei , KE Ming , DING Wanjian , LIU Ruozhuang
Published: March 2009

The potential energy surfaces of nine molecular reactions for the ground‐state CH3C(O)SH and CH3C(S)OH have been investigated with a B3LYP method in conjugation with 6‐31G∗︁∗︁, cc‐pVDZ, aug‐cc‐pVDZ, and cc‐pVTZ basis sets. The present calculations predict that thioacetic acid mainly exists as a CH3C(O)SH tautomer, and both tautomers predominately adopt syn conformations, which reproduces the experimental observations. By comparison of the reactivity difference among CH3C(O)SH, CH3C(S)OH, and CH3C(O)OH, it can be concluded that the replacement of atom O by S in –OH group of CH3C(O)OH has a big effect on the molecular decompositions only when –SH takes part in the reaction as one group, while the CO or CS group has minor contribution to the reactivity difference.
Investigation of Vapor‐Liquid Nucleation for Associating Fluids by Density Gradient Theory
Authors: FU Dong , LIU Jianmin
Published: March 2009

An equation of state (EOS) applicable to both the uniform and non‐uniform associating fluids was established by using the density‐gradient expansion, in which the influence parameter κ is formulated as a function of temperature. The molecular parameters were regressed by fitting to the experimental data of vapor pressures and liquid densities. Within the framework of density gradient theory (DGT), the nucleation rates for water, heavy water, methanol, ethanol, 1‐propanol, 1‐butanol, 1‐pentanol and 1‐hexanol were calculated. The results were satisfactory compared with the experimental data. Our study shows that DGT preserves all the advantages of density functional theory (DFT) in capturing the structure and properties of nucleus but gives much more accurate nucleation rates by adjusting the influence parameter.
Electrochemical Studies of 1,4‐Bis[2‐(2‐pyridyl)‐vinyl] Benzene and 1,4‐Bis[2‐(4‐pyridyl) vinyl] Benzene Laser Dyes via Cyclic Voltammetry, Convolutive Voltammetry and Digital Simulation Methods
Authors: EL‐DALY Samy A. , EL‐HALLAG Ibrahim S , EBEED Ezeiny M , GHONEIM Mohamed M
Published: March 2009

Electrochemical properties of two diolefinic laser dyes namely 1,4‐bis[2‐(2‐pyridyl)‐vinyl] benzene (2PVB) and 1,4‐bis[2‐(4‐pyridyl) vinyl] benzene (4PVB) have been investigated using cyclic voltammetry and convolutive voltammetry combined with digital simulation at a platinum electrode in 0.1 mol/L tetrabutyl ammonium perchlorate (TBAP) in the two different solvents acetonitrile (CH3CN) and dimethylformamide (DMF). The species were reduced via consumption of two sequential electrons to form radical anion and dianion. In switching the potential to positive direction, the two compounds were oxidized by loss of one electron, which was followed by a fast isomerisation process. The electrode reaction pathway and the electrochemical parameters of the investigated compounds were determined using cyclic voltammetry. The extracted electrochemical parameters were verified and confirmed via digital simulation and convolutive voltammetry methods.
Photoelectrochemical Study of Corrosion Resisting Property of Cupronickel B10 in Simulated Cooling Water
Authors: XU Qunjie , WAN Zongyue , ZHOU Guoding , YIN Renhe , CAO Weimin , LIN Changjian
Published: March 2009

The corrosion behavior for cupronickel B10 electrode in simulated cooling water has been studied by using cyclic voltammetry, a photocurrent response method and electrochemical impedance spectroscopy (EIS). The cupronickel electrode shows a p‐type photoresponse to positive and negative potential scan, which comes from Cu2O layer on its surface, but its iph,max is less than that in borax buffer solution. The corrosion resisting property of the cupronickel B10 electrode appeared worse with the increase in the concentrations of Cl−, SO42− and S2− ions, as well as with increasing pH. The rise in the temperature may result in a photoresponse changes from p‐type to n‐type, and the corrosion resisting property fell simultaneously. The results of the EIS measurement agree well with those obtained by a photoelectrochemical method.
Highly Selective Perchlorate Membrane Electrode Based on Cobalt(III) Schiff Base as a Neutral Carrier
Authors: SHOKROLLAHI Ardeshir , GHAEDI Mehrorang , RAJABI Hamid Reza , KIANFAR Ali Hossein
Published: March 2009

A highly selective poly(vinyl chloride) (PVC) membrane electrode based on Co(III)‐Schiff base [Co(5‐NO2‐ Salen)(PBu3)]ClO4·H2O (where 5‐NO2‐SalenHbis(5‐nitrosalycilaldehyde)ethylenediamine) as a new carrier for construction of perchlorate‐selective electrode by incorporating the membrane ingredients on the surface of a graphite electrodes has been reported. The proposed electrode possesses a very wide Nernestian potential linear range to perchlorate from 1.0×10−6 to 5.0×10−1 mol·L−1 with a slope of (59.4±0.9) mV per decade of perchlorate concentration with a low detection limit of 5.0×10−7 mol·L−1 and good perchlorate selectivity over the wide variety of other anions. The developed electrode has an especially fast response (<5 s) and a wide pH independent range (3.0–12.0) in comparison with recent reported electrodes and can be used for at least 2 months without any considerable divergence in their potential response. This electrode was used for the determination of perchlorate in river water, drinking water, sludgy water and human urine with satisfactory results without complicated and time consuming pretreatment.
One Step Preparation of Controlled Drug Release Systems in Supercritical Carbon Dioxide
Authors: CAO Liqin , WANG Chengwei , CHEN Liuping
Published: March 2009

Drug delivery systems based on copolymers of N‐isopropylacrylamide were first prepared by a one step method, in which supercritical carbon dioxide was simultaneously used as a polymerization medium and an impregnation agent. The obtained microspheres were characterized by scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and X‐ray diffraction (XRD). The release effect of the in situ prepared microgels impregnated with ibuprofen was presented through in vitro release simulation.
Mechanism for OH‐Initiated Oxidation of n‐Octane in the Presence of O2 and NO: A DFT Study
Authors: ZHAO Yan , WANG Hui , SUN Xiaomin , ZHANG Qingzhu , WANG Wenxing
Published: March 2009

Density functional theory was used to study the mechanism for the OH‐initiated atmospheric oxidation of n‐octane in the presence of O2 and NO. The geometries and frequencies of the reactants, transition states, intermediates, and products were calculated at the B3LYP/6‐31G(d) level and single‐point energy calculations were carried out with a large basis set, 6‐311+G(3df, 2p). All of the possible product channels have been studied, but only the main ones are reported. The main products obtained are hydroxynitrates and hydroxycarbonyls, which have relative low vapor pressure and are inclined to form secondary organic aerosol. The theoretical results were compared with the available experimental observations.
Peroxo Complexes of Molybdenum(VI) Containing Mannich Base Ligands
Authors: SHARMA Mohita , SALEEM Mohd. , PATHANIA M. S. , SHEIKH H. N. , KALSOTRA B. L.
Published: March 2009

The molybdenum(VI)‐peroxo complexes containing Mannich base ligands having a formula as [MoO(O2)2(L‐L)] [where L‐L=morpholinobenzyl benzamide (MBB), piperidinobenzyl benzamide (PBB), morpholinobenzyl urea (MBU), piperidinobenzyl urea (PBU), morpholinobenzyl thiourea (MBTU), piperdinobenzyl thiourea (PBTU)] have been synthesized and characterized by physico‐chemical, electrochemical techniques and TGA/DTA studies. The complexes have been prepared by stirring ammonium molybdate and excess of 30% aqueous‐H2O2 and then treatment with ethanolic solution of the ligand. Studies revealed that these complexes were non‐electrolytes and diamagnetic in nature. The ligands are bound to metal in a bidentate mode through carbonyl oxygen/thiocarbonyl sulphur and the ring nitrogen. The cyclic voltammograms of the complexes show two quasi‐reversible steps involving complexes. The complexes have also been tested for antibacterial activity against Salmonella and Kleibsella. The antibacterial study of the ligands and complexes indicate that the complexes exhibit higher activity than the free ligands.
Synthesis and Characterization of Three Diverse Coordination Frameworks under Co‐ligand Intervention
Authors: LIU Ping , LIU Jianqiang , WANG Yaoyu , LIANG Yanping , WU Zhensen , SHI Qizhen
Published: March 2009

The chelating organic ligands of 2,2′‐bipyridine (2,2′‐bipy), di(pyrid‐2‐yl)amine (dpa) and 2,6‐di(pyrid‐2‐ylamino)pyridine (dpap) were respectively applied to react with H2fum (fumaric acid) and copper salts, affording three different complexes [Cu2(fum)(2,2′‐bipy)4]·2ClO4 (1), [Cu2(µ‐OH)2(fum)(dpa)2]·2H2O (2) and [Cu(SO4)(H2O)(dpap)]·H2O (3). These complexes were determined by single‐crystal X‐ray diffraction. Each penta‐coordinated Cu(II) ion exhibits a distorted trigonal bipyramidal geometry in 1. The fum ligand links copper ions to form a dinuclear copper unit. While in 2, the fum ligands connect [Cu2(µ‐OH)2(dpa)2] unit to construct a 1D zigzag chain. Unexpectedly, when dpap instead of dpa was used under the same conditions, only one mononuclear complex 3 was formed. Crystal packings show that 1–3 form 3D supramolecular architectures through non‐covalent interactions (multiple hydrogen bonds and C–H··· π/π‐π interactions). In addition, the study of the magnetic property reveals dominating ferromagnetic interactions between Cu(II) atoms in 1.