bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of atmospheric optical turbulence for laser propagation
Authors: Mahalov A. , Moustaoui M.
Published: May 2009

The performance of imaging or transmission systems is limited by atmospheric inhomogeneities and fluctuations. Temperature and pressure variations associated with turbulent eddies cause random fluctuations of the refractive index structure constant (Cn2), which distort optical waves. The distortions may lead to significant blurring, scintillations, broadening and wander of the laser beam. High resolution nested numerical simulations are used to predict and characterize Optical Turbulence (OT) induced by jet streams and gravity waves under various local atmospheric conditions. Non‐homogeneous, anisotropic, non‐Kolmogorov patchy shear‐stratified turbulence in the Upper Troposphere and Lower Stratosphere (UTLS) requires that a fine mesh be used to resolve stiff velocity and temperature gradient profiles. Computational approach is based on nesting and refined vertical gridding in nested mesoscale/microscale codes. This methodology is applied to the analysis of field data from observations. Local distributions of simulated optical turbulence in the UTLS are obtained using very high resolution explicit simulations and parametrization formula. They show strongly laminated structures with thin layers of high values of the refractive index. These optical layers are characterized by steep vertical gradients of potential temperature and are located at the edges of relatively well mixed regions produced by shear instabilities and wave breaking.
Control of Induced Chirality in Optically Active Poly(N‐propargylcarbamate) Films by Solvent Vapor
Authors: Fukushima Toshiyuki , Tsuchihara Kenji
Published: May 2009

Chiral polyethyne derivatives with lyotropic liquid‐crystalline properties are found to be able to self‐assemble, forming two chiral organizations with opposite handedness in solid thin films by selection of the casting solvent and its concentration. After the film preparation, chiral organization could also be induced by simple exposure to an appropriate organic solvent's vapor for several minutes without thermal treatment. Furthermore, irreversible inversion of the handedness of the chiral organization in the film could be achieved by exposure to solvent vapor.

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Ferroelectric Poly(vinylidene fluoride‐trifluoroethylene‐chlorotrifluoroethylene)s: Effect of Molecular Weight on Dielectric Property
Authors: Zhao Chuanqi , Guo Maotian , Lu Yingying , Wang Qing
Published: May 2009

A series of ferroelectric poly(vinylidene fluoride‐trifluoroethylene‐ chlorotrifluoroethylene), P(VDF‐TrFE‐CTFE), have been synthesized by a two‐step approach. The first step is copolymerization of VDF and CTFE via solution or suspension methods to produce P(VDF‐CTFE) copolymers with different molecular weights. The second step is partial de‐chlorination to convert copolymers into P(VDF‐TrFE‐CTFE) terpolymers with precisely controlled compositions. The effect of molecular weight, molecular weight distribution and uniaxially stretching on the dielectric properties has been investigated over a broad range of temperature and frequency. The X‐ray diffraction patterns and DSC curves demonstrate the coexistence of the multiple phases in the terpolymers. The dielectric spectra depict the local relaxation processes and relaxor ferroelectric behavior on the basis of the dielectric loss tangent as a function of temperature.
Surface Modification of Polydimethylsiloxane Substrates with Nonfouling Poly(Poly(ethylene glycol)methacrylate) Brushes
Authors: Tugulu Stefano , Klok Harm‐Anton
Published: May 2009

This contribution presents a new strategy to grow nonfouling poly (poly(ethylene glycol)methacrylate) (PPEGMA) brushes from polydimethylsiloxane (PDMS) substrates. The strategy presented here is based on the use of a sequence of vapor deposition/hydrolysis cycles to generate a surface‐confined atom transfer radical polymerization (ATRP)‐initiator functionalized interpenetrating polymer network (IPN) layer. In contrast to most other approaches that have been developed to graft thin polymer layers from PDMS substrates, this technique obviates the need for UV/ozone pretreatment of the PDMS substrate. It is shown that the surface‐confined ATRP‐initiator functionalized IPN layer can be used to grow PPEGMA brushes in a controlled fashion and that the resulting PPEGMA coating significantly reduces nonspecific protein adsorption as compared to unmodified PDMS substrates.
What Factors Determine Hierarchical Structure of Microbial Cellulose – Interplay among Physics, Chemistry and Biology –
Authors: Koizumi Satoshi , Tomita Yoko , Kondo Tetsuo , Hashimoto Takeji
Published: May 2009

A microbial cellulose film (pellicle), prepared by Acetorbactor xylinum, is a supramolecule system, absorbing a huge amount of water (99% by weight). To elucidate the affinity to water, we investigated the hierarchical structure in a pellicle by using ultra‐small‐angle and small‐angle neutron scattering, observing a wide range of length scales from nm to µm. We successfully determined mass fractal dimensions for the amorphous structure, which hierarchically varies local concentration fluctuations, bundle and network, appeared as the length scale increases. On a basis of these findings, we discuss to address a question what factors determine the hierarchy in the microbial cellulose. This is a new topic of soft matter science, regarded as reaction‐induced self‐assembly in a non‐equilibrium open system, therein soft matter physics, biochemistry and cell biology crucially interplay.
Thermoplastic Starch
Authors: Stepto R.F.T.
Published: May 2009

The thermoplastics processing of native starch in the presence of water is a recent development with very wide possible applications. Eventually, oil‐based polymer materials have to be replaced in many applications by sustainable, inexpensive, natural materials from renewable resources. The present contribution focuses on the injection moulding of starch. The bases of the processing and the thermal and molecular changes occurring are described. In addition, the rheological behaviour of starch‐water melts during processing is analysed quantitatively to give apparent melt viscosities. The dimensional, thermal and mechanical properties of moulded thermoplastic starch polymer (TSP) materials and the products presently being produced from them are discussed.
Poly(methyl methacrylate) Membrane: Dynamic Measurement of Concentrations During Water‐Induced Phase Separation
Authors: Karimi Mohammad , Kish Mohammad Haghighat
Published: May 2009

The properties of membranes produced by nonsolvent‐induced phase separation (NIPS) depend on the rate of mass transfer of mobile components. This paper reports the use of Fourier transform infrared‐attenuated total reflectance (FTIR‐ATR) using principle component regression (PCR) analysis to study the compositional change of polymer solution immersed into the water prior to the phase demixing. To correlate the compositional change with the macroscopic structure, the observation on the dynamics of NIPS is made by a low magnification optical microscope equipped with a video camera. The morphology of the films was also examined by scanning electron microscope. Acetone and N, N‐dimethylformamide were chosen as solvents to present different behavior of poly (methyl methacrylate) (PMMA) solutions during the NIPS process. The ratio of solvent and nonsolvent exchange, flux ratio $d\phi _2 /d\phi _1 $ shows the mass transfer in the homogeneous polymer solution after immersion in a nonsolvent bath. The results show that the flux ratio ($d\phi _2 /d\phi _1 $) is affected by solvents which probably affects the ultimate structures of the precipitated polymer.
Dynamics of Poly(vinylmethyl ether) Blends with a Strongly Interassociating Copolymer
Authors: Masser Kevin A. , Runt James
Published: May 2009

We apply broadband dielectric relaxation spectroscopy to probe the dynamics of hydrogen bonded polymer blends. A copolymer consisting of 2,3‐dimethylbutadiene (DMB) [86%] and p‐(hexafluoro‐2‐hydroxyl‐2‐propyl)styrene (HFS) [14%] was synthesized and blended with poly(vinylmethyl ether) (PVME). The copolymer is capable of forming strong intermolecular hydrogen bonds, while minimizing the degree of intramolecular associations, and its blends with PVME are predicted to be miscible over the entire composition range. Two segmental processes, α and α1, are present in blends containing 26, 50, and 76 weight percent copolymer. The slower process (α1) is assigned to the segmental motion of the intermolecularly associated copolymer, and the faster process (α) to segmental motions of PVME modified by the HFS:DMB copolymer. A relaxation associated with residual water is present in the glassy state. A local process due to motions of the PVME ether groups (β) is also present in the glassy state, and does not change with blend composition.
Preparation and Properties of Biodegradable Slow‐Release PAA Superabsorbent Matrixes for Phosphorus Fertilizers
Authors: Tyliszczak B. , Polaczek J. , Pielichowski J. , Pielichowski K.
Published: May 2009

Biodegradable superabsorbent matrixes for a slow‐release fertilizer were prepared by using crosslinked acrylic acid and water‐soluble granular phosphorus fertilizer KH2PO4. The effects of the amount of crosslinker, initiator and phosphorus fertilizer concentration on water absorption were investigated and optimized. The products show excellent slow release and water‐retention capacity, being nontoxic in soil and environment‐friendly, and could be useful especially in agricultural and horticultural applications. The results showed that the hydrogel structure and swelling capacity was affected by various factors, such as concentration of crosslinker and initiator, as well as by the amount of KH2PO4.
Electromyography and mechanomyography of elbow agonists and antagonists in Parkinson disease
Authors: Marusiak Jarosław , Jaskólska Anna , Jarocka Ewa , Najwer Wojciech , Kisiel‐Sajewicz Katarzyna , Jaskólski Artur
Published: May 2009

The purpose of this study was to assess the electromyographic (EMG) and mechanomyographic (MMG) activities of agonist and antagonist muscles in Parkinson disease patients during maximal isometric elbow contraction in flexion and extension. Ten elderly females with Parkinson disease (average age 75 years) and 10 age‐matched healthy females were tested. The torque and the EMG and MMG signals from biceps brachii and triceps brachii were recorded during sustained maximal voluntary isometric contraction of the elbow flexors and extensors. There were no intergroup differences in the EMG and MMG activities of agonist and antagonist muscles or in torque. This might be because the Parkinson subjects were tested during their medication “ON” phase, or perhaps maximal isometric contraction (MVC) induced greater active muscle stiffness that affected the MMG signal. Muscle Nerve 40: 240–248, 2009
Quantification of dental caries by osteologists and odontologists—a validity and reliability study
Authors: Liebe‐Harkort C. , Ástvaldsdóttir Á. , Tranæus S.
Published: May 2009

As in modern populations, dental caries in early populations is linked to diet and general health. In order to record not only advanced disease states with frank cavitation of teeth but also early lesions, indicating the presence of the disease in a population, it is important that the archaeologist can correctly detect and classify lesions of varying severity. The present study compares and contrasts quantification of dental caries by osteologists and odontologists. Four osteologists and four odontologists undertook visual and radiographic inspection of 61 teeth from three different sources: medieval, 19th century and modern. Separate sets of criteria were applied to disclose observer confidence in detecting a lesion and in estimating lesion extent. For validation of visual assessments, the teeth were sectioned. Radiographic assessments were validated by a specialist in dental radiography. The results disclosed that the odontologists in general showed greater sensitivity than the osteologists, correctly identifying carious lesions, but the osteologists had higher specificity, correctly identifying healthy teeth. Thus, the osteologists tend to overlook carious lesions (under‐diagnosis), while the odontologists tend to incorrectly record lesions in healthy teeth (over‐diagnosis). For both osteologists and odontologists, correct assessment was poorer for radiographs than for visual inspection. Copyright © 2009 John Wiley & Sons, Ltd.
Osseous talocalcaneal coalition in a medieval skeleton (ca. 1050 AD)
Authors: Hofmann M. I. , Böni T. , Rühli F. J.
Published: May 2009

Tarsal coalition (TC) is defined as an abnormal fusion of two or more tarsal bones. The fusion may be fibrous, cartilaginous or osseous and can be congenital or acquired in response to infection, articular disorders, trauma, neoplasm or surgery. We report a case of a talocalcaneal (TCC) type of tarsal coalition in a medieval skeleton from Northwest Germany dating to ca. 1050 AD. The fusion is of osseous type. Plain AP radiographs and computed tomography confirmed the macroscopic diagnosis. Copyright © 2009 John Wiley & Sons, Ltd.
On the Plasma Chemistry of CH4H2Ar System Relevant to Diamond Deposition Process by Plasma Enhanced Chemical Vapor Deposition
Authors: Shokri Babak , Yaghmaee Maziar S. , Sarani Abdollah
Published: May 2009

Diamond films are extensively deposited using plasma enhanced chemical vapor deposition (PECVD). In this work, the most important non‐neutral plasma surface processes, which are needed to analyze the deposition mechanism of diamond films from plasma gas phase, are considered. Moreover, the role of ionic species, which is mostly neglected in deposition investigations, has been considered. To analyze the diamond deposition process, we use the reaction probability algorithm for different surface phenomena. Then, using different methods like Motz and Wise modified relation, the reaction probability is transformed to the mass action kinetic rate constant. Our results lead to the calculation of rate coefficients for non‐neutral gas‐surface reactions that take place during the diamond deposition from plasma in CH4H2Ar system.
Tribological Behaviour of Diamond‐Like Carbon Films used in Automotive Application: A Comparison
Authors: Jarry Olivier , Jaoul Cédric , Tristant Pascal , Merle‐Méjean Thérèse , Colas Maggy , Dublanche‐Tixier Christelle , Ageorges Hélène , Lory Claude , Jacquet Jean‐Marie
Published: May 2009

Excellent tribological behaviour such as high wear resistance and very low friction coefficient make diamond‐like carbon (DLC) very interesting for automotive applications in order to reduce friction losses in engines. In this work, mechanical properties, structure and tribological behaviour of two DLC films (DLC‐A and B) designed for automotive applications are compared. Better hardness and Young modulus of one of the coating are investigated by Raman analysis. Two laboratory tribometers with and without lubrication are used to evaluate the tribological behaviour of both coatings. In each test, a running‐in period is clearly identified. Most of the wear takes place during this period which also presents a higher friction coefficient. Even if the structure of both DLC films remains stable in depth during the test, the DLC‐B has the best wear resistance for both lubricated and unlubricated conditions. Later on, this best wear resistance of DLC‐B is validated by measurement on test rig.
A High Density Hollow Cathode Plasma PECVD Technique for Depositing Films on the Internal Surfaces of Cylindrical Substrates
Authors: Lusk D. , Casserly T. , Gupta M. , Boinapally K. , Cao Y. , Ramamurti R. , Desai P.
Published: May 2009

A novel technique for depositing thick diamond‐like carbon‐based films on the internal surface of cylindrical substrates, like pipes, tubes and valves, has been developed. Plasma assisted chemical vapour deposition technology is used to generate a high density hollow cathode plasma within the pipe using asymmetric direct current pulse biasing. The pipe itself is the vacuum and plasma chamber. A description of the general properties of the films, as well as the excellent corrosion resistant properties will be discussed. It is believed that the described film can increase the component life in applications where internal surfaces are exposed to highly corrosive and abrasive media.
Dispersion of Cerium‐Based Nanoparticles in an Organosilicon Plasma Polymerized Coating: Effect on Corrosion Protection
Authors: Bardon Julien , Bour Jerôme , Del Frari Doriane , Arnoult Claire , Ruch David
Published: May 2009

Plasma polymerized (pp) layers are promising owing to their ease of deposition. Moreover, incorporation of suitable nanoparticles into a polymer matrix can provide improved properties, for instance an increased corrosion resistance, to the final nanocomposite layer. The efficiency of such an incorporation is highly dependent of the layer structure in general, and more particularly of nanoparticles dispersion in the coating. The synthesis of a hybrid coating for anticorrosion purpose is described. Deposition of a plasma polymerized hexamethyldisiloxane (ppHMDSO) coating matrix with aluminum–cerium oxide nanoparticles incorporation is performed by means of an atmospheric pressure plasma reactor in a dielectric barrier discharge (DBD) configuration. Admixture of ethanol within hexamethyldisiloxane (HMDSO) is carried out in order to improve homogeneity and properties of the coating.
Microstructure and Oxidation Resistance of Fe3Al Coatings on Austenitic Stainless Steel by Spark Plasma Sintering
Authors: Nishimoto Akio , Akamatsu Katsuya
Published: May 2009

Fe3Al intermetallic compound layers were coated on austenitic stainless steel SUS304 by the spark plasma sintering (SPS) process to improve its wear and oxidation resistances. The coating was carried out at 1 173 K for 0.6–10.8 ks at a coating pressure of 3–45 MPa. The coatings were densified with increase in the sinter‐coating temperature and pressure. The tensile strength of the coatings was 30–50 MPa. These coatings fractured at the interface between the coatings and the substrate. The mass increase of coated specimen after oxidizing at 1 123 K for 1 000 ks was less than that of the untreated specimen. This result indicates that the Fe‐Al intermetallic compound coating markedly improved the oxidation resistance of the austenitic stainless steel.
Active‐layer characteristics and summer climatic indices, Mackenzie Valley, Northwest Territories, Canada
Authors: Smith Sharon L. , Wolfe Stephen A. , Riseborough Daniel W. , Nixon F. Mark
Published: May 2009

Summer thaw depths at eight monitoring sites in the Mackenzie Valley, determined from probing of grids and thaw tubes, are used to characterise the spatial and temporal variations in active‐layer thickness and to investigate linkages to climatic variations. Intra‐site variability in thaw depths is typically low where organic cover is thin and uniform. Higher variability occurs where moisture contents and organic cover are high and spatially variable.

Grid‐mean thaw depths provide robust measures of the average site thaw depth, although they are less than annual maximum active‐layer thicknesses determined by thaw tubes. Values from both measurements correlate reasonably well, permitting estimates of the variations in active‐layer thickness from grid‐mean thaw depths.

Active‐layer response to thermal forcing in various settings is well represented by grid‐mean thaw depths and the square‐root of late‐season thawing‐degree days. However, the effect of interannual climate variability on active‐layer thickness is better assessed by maximum tube thaw depths and the square‐root of total thawing‐degree days. Copyright © 2009 Her Majesty the Queen in right of Canada. Published by John Wiley & Sons, Ltd.
Antiplasmodial activity of isolated compounds from Carpesium divaricatum
Authors: Chung Ill‐Min , Seo Su‐Hyun , Kang Eun‐Young , Park Won‐Hwan , Park Sun‐Dong , Moon Hyung‐In
Published: May 2009

The whole plants of Carpesium divaricatum are used in traditional medicine as an antipyretic, analgesic and vermifugic, including a topical application for sores and inflammation. In a previous paper, the isolation and structural elucidation of isolated ineupatorolides A from methanol extracts of C. rosulatum (Compositae) were reported. The present paper deals with the isolation and identification of antiplasmodial compounds from C. divaricatum in Carpesium spp. Five compounds, 1β,6α‐dihydroxy‐4(15)‐eudesmene [1], β‐dictyopterol [2], 2‐isopropenyl‐6‐acetyl‐8‐methoxy‐1,3‐benzodioxin‐4‐one [3], (3E,6E,10E,14E,18E)‐2,6,10,15,19,23‐hexamethyl‐3,6,10,14,18,22‐tetracosahexaen‐2‐ol [4] and neophytadiene [5], were isolated from the whole plants of C. divaricatum. The in vitro activity against P. falciparum strain D10 was assessed using the parasite lactate dehydrogenase assay method. The main antiplasmodial principle, 2‐isopropenyl‐6‐acetyl‐8‐methoxy‐1,3‐benzodioxin‐4‐one [3], has been isolated from C. divaricatum for the first time. Compound 3 exhibited an antiplasmodial activity with IC50 values of 2.3 ± 0.3 μm. This is the first report on the antiplasmodial activity of the compounds from C. divaricatum. Copyright © 2009 John Wiley & Sons, Ltd.
Latent variable mining with its applications to anomalous behavior detection
Authors: Hirose Shunsuke , Yamanishi Kenji
Published: May 2009

In this paper, we propose a new approach to anomaly detection by looking at the latent variable space to make the first step towardlatent anomaly detection. Most conventional approaches to anomaly detection are concerned with tracking data which are largely deviated from the ordinary pattern. In this paper, we are instead concerned with the issue of how to track changes occurring in the latent variable space consisting of the meta information existing behind directly observed data. For example, in the case of masquerade detection, the conventional task was to detect anomalous command lines related to masqueraders' malicious behaviors. Meanwhile, we rather attempt to track changes of behavioral patterns such aswriting mails,making software, etc. which are information of more abstract level than command lines. The key ideas of the proposed methods are: (i) constructing the model variation vector, which is introduced relative to the latent variable space, and (ii) the latent anomaly detection is reduced to the issue of change‐point detection for the time series that the model variation vector forms. We demonstrate through the experimental results using an artificial data set and a UNIX command data set that our method has significantly enhanced the accuracy of existing anomaly detection methods. Copyright © 2009 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 2: 48‐69, 2009
Lightening the performance burden of individual‐based models through dimensional analysis and scale modeling
Authors: Osgood Nathaniel
Published: May 2009

While individual‐based models are attractive for some modeling problems, the lengthy times required for simulating large populations can impose high opportunity costs by limiting model comprehension, refinement and user interaction. This paper demonstrates a novel technique for using dimensional analysis and scale modeling to reduce the performance barriers associated with individual‐based model simulation. Given a dimensionally homogeneous simulation model with a large population, we propose a rigorous, systematic and general‐purpose technique to formulate a “reduced‐scale” individual‐based model that simulates a smaller population. Outputs of the reduced‐scale models can be precisely transformed to yield results representative of a full‐scale model—without the need to run the full‐scale model. While discretization effects and heterogeneity limit the degree of scaling that can be achieved, these techniques are notable in relying only upon dimensional homogeneity of the full‐scale model, and not on the specifics of model behavior or use of a particular mathematical framework. Copyright © 2009 John Wiley & Sons, Ltd.
Methotrexate delivery via folate targeted dendrimer‐based nanotherapeutic platform
Authors: Majoros István J. , Williams Christopher R. , Becker Andrew , Baker James R.
Published: May 2009

This paper provides a synopsis of the advancements made in advancing a dendrimer‐based nanomedicine towards human clinical trials by the Michigan Nanotechnology Institute for Medicine and Biological Sciences. A brief description of the synthesis and characterization of a targeted multifunctional therapeutic will demonstrate the simple yet delicate task of producing novel chemotherapeutic agents. The results obtained from in vitro and in vivo studies not only authenticate the potential of using nanoparticles to target therapeutics but also provide valuable insight towards the future directions of this technology. A fundamental, cross‐disciplinary collaboration was necessary to achieve the synthesis and testing of this technology, and was the keystone to establishing this innovative invention. Throughout this paper, we will stress that the unique collaboration that facilitated the evolution of this technology is vital to the success of future developments in nanomedicine. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease
Role of neutrophils in innate immunity: a systems biology‐level approach
Authors: Kobayashi Scott D. , DeLeo Frank R.
Published: May 2009

The innate immune system is the first line of host defense against invading microorganisms. Polymorphonuclear leukocytes (PMNs or neutrophils) are the most abundant leukocyte in humans and essential to the innate immune response against invading pathogens. Compared with the acquired immune response, which requires time to develop and is dependent on previous interaction with specific microbes, the ability of neutrophils to kill microorganisms is immediate, non‐specific, and not dependent on previous exposure to microorganisms. Historically, studies on PMN‐pathogen interaction focused on the events leading to killing of microorganisms, such as recruitment/chemotaxis, transmigration, phagocytosis, and activation, whereas post‐phagocytosis sequelae were infrequently considered. In addition, it was widely accepted that human neutrophils possessed limited capacity for new gene transcription and thus, relatively little biosynthetic capacity. This notion has changed dramatically within the past decade. Further, there is now more effort directed to understand the events occurring in PMNs after killing of microbes. Herein we review the systems biology‐level approaches that have been used to gain an enhanced view of the role of neutrophils during host‐pathogen interaction. We anticipate that these and future systems‐level studies will ultimately provide information critical to our understanding, treatment, and control of diseases caused by pathogenic microorganisms. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Physiology > Organismal Responses to Environment
Novel copy number variants in children with autism and additional developmental anomalies
Authors: Davis L. K. , Meyer K. J. , Rudd D. S. , Librant A. L. , Epping E. A. , Sheffield V. C. , Wassink T. H.
Published: May 2009

Autism is a neurodevelopmental disorder characterized by three core symptom domains: ritualistic-repetitive behaviors, impaired social interaction, and impaired communication and language development. Recent studies have highlighted etiologically relevant recurrent copy number changes in autism, such as 16p11.2 deletions and duplications, as well as a significant role for unique, novel variants. We used Affymetrix 250K GeneChip Microarray technology (either NspI or StyI) to detect microdeletions and duplications in a subset of children from the Autism Genetic Resource Exchange (AGRE). In order to enrich our sample for potentially pathogenic CNVs we selected children with autism who had additional features suggestive of chromosomal loss associated with developmental disturbance (positive criteria filter) but who had normal cytogenetic testing (negative criteria filter). We identified families with the following features: at least one child with autism who also had facial dysmorphology, limb or digit abnormalities, or ocular abnormalities. To detect changes in copy number we used a publicly available program, Copy Number Analyser for GeneChip® (CNAG) Ver. 2.0. We identified novel deletions and duplications on chromosomes 1q24.2, 3p26.2, 4q34.2, and 6q24.3. Several of these deletions and duplications include new and interesting candidate genes for autism such as syntaxin binding protein 5 (STXBP5 also known as tomosyn) and leucine rich repeat neuronal 1 (LRRN1 also known as NLRR1). Lastly, our data suggest that rare and potentially pathogenic microdeletions and duplications may have a substantially higher prevalence in children with autism and additional developmental anomalies than in children with autism alone.
Deficient NRG1-ERBB signaling alters social approach: relevance to genetic mouse models of schizophrenia
Authors: Moy Sheryl S. , Troy Ghashghaei H. , Nonneman Randal J. , Weimer Jill M. , Yokota Yukako , Lee Daekee , Lai Cary , Threadgill David W. , Anton E. S.
Published: May 2009

Growth factor Neuregulin 1 (NRG1) plays an essential role in development and organization of the cerebral cortex. NRG1 and its receptors, ERBB3 and ERBB4, have been implicated in genetic susceptibility for schizophrenia. Disease symptoms include asociality and altered social interaction. To investigate the role of NRG1-ERBB signaling in social behavior, mice heterozygous for an Nrg1 null allele (Nrg1+/−), and mice with conditional ablation of Erbb3 or Erbb4 in the central nervous system, were evaluated for sociability and social novelty preference in a three-chambered choice task. Results showed that deficiencies in NRG1 or ERBB3 significantly enhanced sociability. All of the mutant groups demonstrated a lack of social novelty preference, in contrast to their respective wild-type controls. Effects of NRG1, ERBB3, or ERBB4 deficiency on social behavior could not be attributed to general changes in anxiety-like behavior, activity, or loss of olfactory ability. Nrg1+/− pups did not exhibit changes in isolation-induced ultrasonic vocalizations, a measure of emotional reactivity. Overall, these findings provide evidence that social behavior is mediated by NRG1-ERBB signaling.
The future global role and development of the US economy
Authors: Furchtgott-Roth Diana
Published: May 2009

The US economy is facing, as are many other economies across the globe, the challenge of overcoming the current recession while having no single satisfactory solution to follow. A result of globalisation is that countries are increasingly interconnected, especially in terms of their economies; consequently, decisions taken in the US will have an effect overseas. After assessing the Obama administration's spending plans in the areas of finance, energy, health care and taxation, Diana Furchtgott-Roth argues that cutting individual tax rates is the most effective measure for overcoming the crisis. A programme to enhance growth will not only restore confidence in the American economy but will also be of benefit to global economies.
The relationship between frequency of family dinner and adolescent problem behaviors after adjusting for other family characteristics
Authors: Sen Bisakha
Published: May 2009

Objective

To examine the association between frequency of family dinners (FFD) and selected problem behaviors for adolescents after adjusting for family connectedness, parental awareness, other family activities, and other potentially confounding factors.

Methods

Data are drawn from the National Longitudinal Survey of Youth, 1997. The primary variable of interest is self‐reported FFD in a typical week. Problem behaviors studied are substance‐use, physical violence, property‐destruction, stealing, running away from home, andgang membership. Multivariate logistic models are estimated for each behaviors. Linear regression models are estimated for behavior‐frequency for the sub‐samples engaging in them. Analysis is done separately by gender.

Results

FFD is negatively associated with substance‐use and running away for females; drinking, physical violence, property‐destruction, stealing and running away for males.

Conclusion

Family meals are negatively associated to certain problem behaviors for adolescents even after controlling rigorously for potentially confounding factors. Thus, programs that promote family meals are beneficial.
Parent–child relationship trajectories during adolescence: Longitudinal associations with romantic outcomes in emerging adulthood
Authors: Seiffge‐Krenke Inge , Overbeek Geertjan , Vermulst Ad
Published: May 2009

This study examined the developmental trajectories of parent–child relationships in adolescence, especially with respect to changes in support levels and negativity, and analyzed if and how these trajectories were associated with the subsequent quality of romantic relationships in young adulthood. A sample of 145 German subjects was followed across six waves (i.e., ages 14, 15, 16, 17, 21, and 23 years). Growth mixture modeling revealed three developmental trajectories of parent–child relationships across adolescence (i.e., normative, increasingly negative, and decreasingly negative/distant), which were associated with the quality of romantic outcomes at two times in emerging adulthood. Earlier mother–adolescent relationships were distinctively linked with connectedness and sexual attraction experienced in young adults' romantic relationships. Distant father–child relationships during adolescence were linked with the child's later anxious love.
Adolescents' relational schemas and their subjective understanding of romantic relationship interactions
Authors: Smith Justin D. , Welsh Deborah P. , Fite Paula J.
Published: May 2009

This study examines the association between adolescents' relational schemas and their subjective understanding of interactions in the context of male–female romantic relationships. We employed an innovative multimodal methodology: the video‐recall system [Welsh, D. P., & Dickson, J. W. (2005). Video‐recall procedures for examining subjective understanding in observational data. Journal of Family Psychology, 19(1), 62–71], which includes both adolescent participants' perspectives, as well as those of trained coders. Dyadic structural equation modeling (SEM) with latent variables was used to examine two dependent variables: Discomfort and Power. Relational schemas were only associated with the participants' interpretation of Discomfort, and did not differ by gender. The association between relational schemas and Power were different by gender, suggesting males and females with more vulnerable relational schemas may employ different strategies to cope with their insecurity. Males' relational schemas were also associated with the observers' interpretations of Power for both couple members. Possible implications of this finding for attachment theory and adolescent romantic relationships are discussed.
Laser‐evoked potentials as a tool for assessing the efficacy of antinociceptive drugs
Authors: Truini A. , Panuccio G. , Galeotti F. , Maluccio M.R. , Sartucci F. , Avoli M. , Cruccu G.
Published: May 2009

Laser‐evoked potentials (LEPs) are brain responses to laser radiant heat pulses and reflect the activation of Aδ nociceptors. LEPs are to date the reference standard technique for studying nociceptive pathway function in patients with neuropathic pain. To find out whether LEPs also provide a useful neurophysiological tool for assessing antinociceptive drug efficacy, in this double‐blind placebo‐controlled study we measured changes induced by the analgesic tramadol on LEPs in 12 healthy subjects. We found that tramadol decreased the amplitude of LEPs, whereas placebo left LEPs unchanged. The opioid antagonist naloxone partially reversed the tramadol‐induced LEP amplitude decrease. We conclude that LEPs may be reliably used in clinical practice and research for assessing the efficacy of antinociceptive drugs.
Acceptance of pain in adolescents with chronic pain: Validation of an adapted assessment instrument and preliminary correlation analyses
Authors: McCracken Lance M. , Gauntlett‐Gilbert Jeremy , Eccleston Christopher
Published: May 2009

It is important to understand the processes that contribute to disability and distress in adolescents with chronic pain. For example, research has identified that when adolescents can positively adapt to the consequences of health condition, rather than attempt to change the condition itself, they also function better and experience less distress. This pattern of behavior is similar to what is referred to as “acceptance” of pain in the adult literature. Although acceptance is consistently associated with positive outcomes in adult studies, there has been less investigation of acceptance in adolescents. This study aimed to examine the reliability and validity of an adolescent‐adapted version of the Chronic Pain Acceptance Questionnaire (CPAQ‐A), and, using this instrument, to carry out a preliminary investigation of acceptance in adolescents with chronic pain. A sample of 122 highly disabled adolescents with chronic pain attending a specialty service completed the adapted CPAQ‐A. They also completed standardized measures of their pain and daily functioning. Results supported the reliability and validity of the CPAQ‐A. Correlation analyses showed that higher levels of acceptance were associated with lower levels of distress and disability, but not with lower pain intensity. Regression analyses were carried out to assess the independent contribution of acceptance after pain intensity and demographic variables were taken into account. In these analyses acceptance accounted for significant variance in disability, psychological distress, and developmental and family functioning. We discuss developmental aspects of acceptance in adolescents and clinical implications of these findings.
House dust mite allergen Der f 1 can induce the activation of latent TGF‐β via its protease activity
Authors: Nakamura Yuki , Miyata Masanori , Shimokawa Naomi , Ohnuma Yuko , Katoh Ryohei , Ogawa Hideoki , Okumura Ko , Nakao Atsuhito
Published: May 2009

A major house dust mite allergen Der f 1 belongs to the papain‐like cysteine protease family. This study investigated whether Der f 1 can cleave the latency‐associated peptide (LAP) of transforming growth factor (TGF)‐β via its proteolytic activity and activate latent TGF‐β. We found that Der f 1 can cleave LAP and induce the activation of latent TGF‐β, leading to functional Smad signaling. Importantly, these actions of Der f 1 were inhibited by cysteine protease inhibitor E64 or inactivation of the protease activity by heat. Thus, latent TGF‐β may be a direct target of Der f 1 protease activity.
Early growth response 1 loops the CYP2B6 promoter for synergistic activation by the distal and proximal nuclear receptors CAR and HNF4α
Authors: Inoue Kaoru , Negishi Masahiko
Published: May 2009

Nuclear xenobiotic receptor CAR activates transcription of the CYP2B6 gene by directly binding to the distal enhancer PB responsive enhancer module (PBREM). This CAR‐mediated activation is synergized by transcription factors early growth response 1 (EGR1) and hepatocyte‐enriched nuclear factor 4α (HNF4α) that bind to the proximal element OA response element KI (OAREKI) [Inoue, K., & Negishi, M. (2008). Nuclear receptor CAR requires early growth response 1 to activate the human cytochrome P450 2B6 gene. J. Biol. Chem. 283, 10425–10432]. Two additional EGR1 binding sites have now been found just downstream from PBREM. Internal deletion of EGR1 sites within the context of the −1.8 kb CYP2B6 promoter, which contains both PBREM and OAREKI, revealed that the distal and proximal EGR1 sites are essential for EGR1 to synergize CAR‐mediated transcription. Chromatin conformation capture 3C assays demonstrated that ERG1 may loop the distal PBREM towards the proximal OAREKI so that together, CAR and HNF4α synergistically activate the CYP2B6 promoter.
Crystal structure of α/β‐galactoside α2,3‐sialyltransferase from a luminous marine bacterium, Photobacterium phosphoreum
Authors: Iwatani Toru , Okino Nozomu , Sakakura Mai , Kajiwara Hitomi , Takakura Yoshimitsu , Kimura Makoto , Ito Makoto , Yamamoto Takeshi , Kakuta Yoshimitsu
Published: May 2009

α/β‐Galactoside α2,3‐sialyltransferase produced by Photobacterium phosphoreum JT‐ISH‐467 is a unique enzyme that catalyzes the transfer of N‐acetylneuraminic acid residue from cytidine monophosphate N‐acetylneuraminic acid to acceptor carbohydrate groups. The enzyme recognizes both mono‐ and di‐saccharides as acceptor substrates, and can transfer Neu5Ac to both α‐galactoside and β‐galactoside, efficiently. To elucidate the structural basis for the broad acceptor substrate specificity, we determined the crystal structure of the α2,3‐sialyltransferase in complex with CMP. The overall structure belongs to the glycosyltransferase‐B structural group. We could model a reasonable active conformation structure based on the crystal structure. The predicted structure suggested that the broad substrate specificity could be attributed to the wider entrance of the acceptor substrate binding site.
Drosophila big brain does not act as a water channel, but mediates cell adhesion
Authors: Tatsumi Kimiko , Tsuji Shoji , Miwa Hideki , Morisaku Toshinori , Nuriya Mutsuo , Orihara Minako , Kaneko Kazunari , Okano Hideyuki , Yasui Masato
Published: May 2009

The neurogenic gene Drosophila big brain (bib) has a high sequence homology to aquaporin‐4. However, its cellular functions in Drosophila neurogenesis have remained elusive. Here we investigated cell adhesion, and the ion and water permeability of Bib. The adhesive function was examined by a cell aggregation assay using L cells. Bib‐transfected L cells formed aggregated clusters, while control‐L cells remained as a single cell suspension. Ion permeation was not confirmed in L cells stably expressing Bib. When expressed in COS7 cells, Bib exhibited limited water permeability. This newly found cell adhesive function of Bib may be important for Drosophila neurogenesis.
Flat panel cone beam computed tomography of the sinuses
Authors: Zoumalan Richard A. , Lebowitz Richard A. , Wang Edwin , Yung Kathryn , Babb James S. , Jacobs Joseph B.
Published: May 2009

Objective

This study aims to compare the image quality and potential diagnostic accuracy of paranasal sinus CT scans generated by flat panel cone beam CT at three specific data acquisition times.

Study Design

Prospective, single blinded analysis.

Subjects and Methods

Eleven patients without previous radiologic evaluation were selected based on history and findings suspicious for chronic sinusitis. Each patient was scanned at three different acquisition times: 10, 20, and 40 seconds. A panel of neuroradiologists and otolaryngologists, blinded to the scan acquisition time, individually reviewed images and rated overall image quality and visualization of specific anatomic sites. Image noise values were also calculated. Techniques were compared with a Wilcoxon matched‐pairs signed ranks test.

Results

Compared to the 10‐second acquisition time, the 40‐ and 20‐second acquisition time techniques had significantly better image quality (P < 0.05) and image noise (P < 0.05). No difference in image quality and image noise existed between the 20‐ and 40‐second techniques. No difference in visualization of specific anatomic structures existed between any of the time techniques.

Conclusion

The quality of flat panel CT imaging of the sinuses directly relates to scan time and thus radiation dose.
Surgeon radiation exposure in ESS with balloon catheters
Authors: Albritton Ford D. , Levine Howard L. , Smith Joseph L. , Rowe‐Jones Julian , Zahurullah Fazlur R. , Armstrong Michael , Duplan Don , Gershow James A. , Leopold Donald A. , Kuhn Frederick A.
Published: May 2009

Objective

Less invasive instruments such as balloon catheters are available for sino‐ostial dilation during endoscopic sinus surgery (ESS). Currently, balloon catheter position is confirmed under fluoroscopic visualization. Radiation exposure has been an area of concern. This study was initiated to determine surgeon radiation exposure when fluoroscopy is used during ESS with balloon catheters.

Study Design

A multi‐center, prospective evaluation of surgeon radiation exposure was conducted.

Subjects and Methods

For three months, 14 sinus surgeons wore dosimeters to record radiation exposure while using C‐arm fluoroscopy during balloon catheter‐aided sinus surgery. One dosimeter was placed at collar level (chest), outside the lead apron and another dosimeter was placed on a finger (extremity). These dosimeters were sent for readings. Deep, eye, and shallow radiation dose for each surgeon was calculated.

Results

Thirteen chest badges recorded annualized averages of 191.08, 193.54, and 187.69 mrems for deep, eye, and shallow exposure respectively. Eleven ring badges recorded 584.00 mrems.

Conclusions

A recent publication reported low levels of surgeon radiation exposure during ESS with balloon catheters. This study validates radiation exposure among experienced surgeons is well below the annual occupational radiation exposure limit of 50,000 mrem. With vigilant technique and education, fluoroscopy reliance can be minimized.
Updated systematic review of tonsillectomy and adenoidectomy for treatment of pediatric obstructive sleep apnea/hypopnea syndrome
Authors: Friedman Michael , Wilson Meghan , Lin Hsin‐Ching , Chang Hsueh‐Wen
Published: May 2009

Objective

Perform an updated systematic review and meta‐analysis to determine the cure rate of tonsillectomy and adenoidectomy (T&A) for pediatric obstructive sleep apnea/hypopnea syndrome (OSAHS).

Methods

A systematic review was performed to identify English‐language studies that evaluate the treatment of pediatric (age < 20 years) OSAHS patients with T&A using polysomnography as a metric of cure. Twenty‐three studies fit the inclusion criteria and a meta‐analysis was performed to determine the overall success. Meta‐analysis was also performed to determine the success in obese and comorbid populations vs cohorts of healthy children.

Results

The meta‐analysis included 1079 subjects (mean sample size of 42 patients) with a mean age of 6.5 years. The effect measure was the percentage of pediatric patients with OSAHS who were successfully treated (k = 22 studies) with T&A based on preoperative and postoperative PSG data. Random‐effects model estimated the treatment success of T&A was 66.3 percent, when cure was defined per each individual study. When “cure” was defined as an apnea‐hypopnea index (AHI) of <1 (k = 9 studies), random‐effects model estimate for OSAHS treatment success with T&A was 59.8 percent. Postoperative mean AHI was significantly decreased from preoperative levels.

Conclusions

Contrary to popular belief, meta‐analysis of current literature demonstrates that pediatric sleep apnea is often not cured by T&A. Although complete resolution is not achieved in most cases, T&A still offers significant improvements in AHI, making it a valuable first‐line treatment for pediatric OSAHS.