bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper(II)-catalyzed ortho-Benzoxylation of 2-Arylpyridines with Sodium Carboxylates
Authors: Li Liping , Yu Peng , Cheng Jiang , Chen Fan , Pan Changduo
Published: May 2012

Copper-catalyzed ortho-benzoxylation of an sp2 C–H bond by sodium carboxylates is described. The procedure tolerates carbomethoxy, formyl, bromo, and chloro groups, providing the benzoxylated products in moderate to good yields.
Fractionation of Au Nanomaterials Using Selective Adsorption of a Long-chain Amidoamine Derivative
Authors: Imura Yoshiro , Morita Clara , Kawai Takeshi
Published: May 2012

Two-step phase transfer using C18AA molecules as the transfer agent was found to be very useful for the fractionation of large Au nanoparticles (NPs) (average diameter 7.7 nm), small Au NPs (average diameter 4.9 nm), and Au nanowires (NWs) according to their surface structural distinction. We also demonstrated that the use of organic solvents with different solubilities for C18AA was effective for the fractionation of Au nanocrystals.
Preparation of Graphene Dispersion and Carbon Nanoscrolls
Authors: Xiong Yuzi , Chen Hao , Ou Encai , Qian Jiangtao , Peng Chang , Xiong Yuanqin , Xu Weijian
Published: May 2012

A novel versatile approach for the bulk and facile preparation of graphene dispersion with high concentration is developed, via sonication of graphite that is intercalated by a mixture of benzene derivative and N-methyl-2-pyrrolidone (NMP). Subsequently, graphene nanoscrolls, a new structure between graphene and nanotubes are obtained by heat treatment of graphene sheets.
Spontaneous Motion of o-Toluidine Droplets: Repetitive Motion of Running and Squashing
Authors: Nanzai Ben , Ishikawa Ryotaro , Igawa Manabu
Published: May 2012

We observed a unique spontaneous motion for an o-toluidine droplet containing iodine in an aqueous solution of cation surfactant. The droplet repeated a running motion and a squashing motion on the glass surface. The contact angle determines the motion of droplets on the glass surface. We analyzed this motion quantitatively using video capture. As the initial trigger of the running motion, the receding contact angle increased before the advancing contact angle increased. The predominant squashing span increased with time, although little change was found in the running span.
Al-doped Ceria: A New Cathode Catalyst for Li–O2 Batteries
Authors: Kalubarme Ramchandra S , Park Chan-Jin
Published: May 2012

Nanostructured aluminum-doped ceria (ADC) particles with uniform spherical shape, as a new catalyst material for the cathode in Li–O2 batteries, are prepared by a solution combustion method. The nonaqueous Li–O2 cell employing the Ce0.8Al0.2O2 catalyst exhibits a specific capacity as high as 1549 mA h g−1. The discharge product of the Li–O2 cell mostly contains lithium carbonate and a small amount of lithium peroxide.
Preparation of Size-controlled Copper-nanoparticle-supported Catalyst Using Rapid and Uniform Heating under Microwave Irradiation
Authors: Fuku Kojirou , Takakura Shuhei , Kamegawa Takashi , Mori Kohsuke , Yamashita Hiromi
Published: May 2012

The size-controlled Cu nanoparticles having average particle size of 4.5, 6.3, and 7.3 nm were prepared on ZnO/SBA-15 mesoporous silica by microwave-assisted alcohol reduction in the presence of surface-modifying ligands possessing different carbon chain length such as sodium laurate (C, 12) and sodium stearate (C, 18), and the efficient hydrogenation reaction of p-nitrophenol to p-aminophenol was achieved by the Cu/ZnO/SBA-15 having Cu nanoparticles with appropriate size.
Preparation of TiO2–Carbon Nanotube Composite Catalysts for Improvement of the Photocatalytic Activity of TiO2
Authors: Takenaka Sakae , Arike Takafumi , Miyazaki Takahiro , Matsune Hideki , Kishida Masahiro
Published: May 2012

TiO2 nanoparticles were deposited on carbon nanotubes (CNTs) for improvement of their photocatalytic activity. CNTs could be uniformly covered with TiO2 nanoparticles by the hydrolysis of titanium tetraisopropoxide in the presence of urea. Urea worked as linker molecules between the CNT surface and the TiO2 nanoparticles. The resultant TiO2–CNT composites showed a high catalytic activity for photodegradation of organic molecules.
Molecular Structure and Magnetic Properties of Pentapyridyl-based Iron(II) and Cobalt(II) Complexes
Authors: Lee Young Hoon , Kato Kazuya , Kubota Emi , Kawata Satoshi , Hayami Shinya
Published: May 2012

Two metal complexes, [Fe(tppda)2](ClO4)2·acetone (1) and [Co(tppda)2](PF6)2·MeOH (2) were synthesized, and their molecular structures and magnetic properties were also characterized by single-crystal X-ray diffraction analysis and magnetic susceptibility. Both compounds showed that six pyridyl groups of two tppda ligands were coordinated to the central metal ion while the remaining four pyridyl and four tertiary-amine substituents existed without coordination. Additionally, the temperature-dependent magnetic susceptibility of both complexes revealed a gradual spin transition for 1 and high-spin state for 2, respectively.
Necklace-shaped Dimethylsiloxane Polymers Bearing a Polyhedral Oligomeric Silsesquioxane Cage Prepared by Polycondensation and Ring-opening Polymerization
Authors: Yoshimatsu Marie , Komori Kunihiro , Ohnagamitsu Yusuke , Sueyoshi Naoto , Kawashima Noriko , Chinen Sumire , Murakami Yuko , Izumi Jin , Inoki Daisuke , Sakai Kiyoshi , Matsuo Takashi , Watanabe Kenichi , Kunitake Masashi
Published: May 2012

A series of necklace-shaped dimethylsiloxane (DMS) polymers bearing a polyhedral oligomeric silsesquioxane (POSS) cage were synthesized from bifunctional POSS by two different synthetic routes. One-step or two-step polycondensation between POSS and dimethyloligosiloxane dichloride led to necklace polymers with constant chain lengths (n = 2–8). The ring-opening polymerization of octamethylcyclotetrasiloxane (D4) with POSS was also found to provide similar necklace-shaped polymers with dispersed chain lengths of DMS. The thermal properties, decomposition temperature (Td5%), and glass-transition temperatures (Tg) of the polymers were strongly dependent on DMS chain length. The polymers with dispersed chain lengths gave higher Tg’s than the polymers with corresponding constant chain lengths. The highest Td5% reached 478 °C.
Synthesis and Properties of Novel i- and g-Line Sensitive Photoacid Generators Based on 9-Fluorenone Derivatives with Aryl–Ethynyl Units
Authors: Kodama Shintaro , Okamura Haruyuki , Shirai Masamitsu
Published: May 2012

Imino sulfonate photoacid generators (PAGs) sensitive to i- and g-line were synthesized using 9-fluorenone derivatives with aryl–ethynyl units as starting materials. The PAGs exhibited good thermal stability and photoreactivity at 365 (i-line) and 436 nm (g-line) compared with that of an imino sulfonate PAG synthesized from unfunctionalized 9-fluorenone.
Energy Partitioning in Single-Electron Transfer Events between Gaseous Dications and Their Neutral Counterparts
Authors: Schröder Detlef
Published: May 2012

Electron-transfer reactions between hydrocarbon dications and neutral hydrocarbons lead to an unequal deposition of the excess energy from the reaction in the pair of monocations formed. The initial observation of this phenomenon was explained by the different states accessible upon single-electron capture by a dication compared to single-electron ejection from a neutral compound. Alternatively, however, isomeric structures of the dicationic species, pronounced Franck–Condon effects, as well as excess energy in the dicationic precursors could cause the asymmetric energy partitioning in such dication/neutral collisions. Here, the investigation of this phenomenon in an interdisciplinary cooperation is described, shedding light not only upon a possible solution to the problem at hand, but also providing an example for the synergistic benefits of international research networks applying complementary approaches.
Catalysis in Hydrogen-Bridged Radical Cations
Authors: Jobst Karl J. , Trikoupis Moschoula A.
Published: May 2012

Hydrogen-bridged radical cations (HBRCs) are an intriguing subclass of ion–molecule complexes. They may act as key intermediates of remarkable stability in both association and dissociation reactions of heteroatom-containing molecular ions. The H-bridge of such an HBRC can promote isomerization of its ionic component by H-transfer. Proton-transport catalysis (PTC) is a prime example. Here, a neutral molecule promotes the smooth transformation of an ion into its H-shift isomer by consecutive proton-transfer reactions. A celebrated case is the water-catalyzed isomerization of CH3OH•+ into its more stable distonic isomer •CH2OH2+. Other early studies of PTC also deal with catalyzing 1,2-H shifts in association reactions. This short review focuses on more recent combined experimental and computational studies of catalysis in HBRCs. Mechanisms involving both proton and H atom transfers have been proposed for a variety of systems of H-shift isomers. It has also become clear that PTC is not confined to bimolecular reactions. It also features in the unimolecular chemistry of heteroatom-containing ions, which have a tendency to isomerize to HBRCs en route to their dissociation.
The Dissociation Chemistry of Ionized Methyl Carbamate and its Isomers Revisited: Theory and Experiment in Concert
Authors: Burgers Peter C. , McGibbon Graham A. , Jobst Karl J.
Published: May 2012

Early combined computational and experimental studies by J.K. Terlouw and colleagues propose that low-energy methyl carbamate ions, NH2COOCH3•+ (MC-1), rearrange into distonic ions NH2C(OH)OCH2•+ and hydrogen-bridged radical cations [NH2C=O–H–OCH2]•+ (MC-5) en route to the observed losses of HCO• and CO. In this study, we report on the generation of ionsMC-5 by decarbonylation of ionized methyl oxamate NH2COCOOCH3•+. Theory and experiment agree that ionMC-5 is a key intermediate in the dissociation of low-energy ionsMC-1. The subsequent HCO• loss, however, may not proceed via the route proposed by Terlouw et al., but rather by an entirely different mechanism involving proton–transport catalysis (PTC) in ionMC-5. This view is further supported by the dissociation behaviour of theMC-5 isotopologue [ND2C=O–D–OCH2]•+, which is conveniently generated from the d3-labelled glycolamide ion DOCH2C(=O)ND2•+
Investigation on the Role of Pneumatic Aspects in Electrospray, Desorption Electrospray Surface Ionization and Surface-Activated Chemical Ionization
Authors: Seraglia Roberta , Molin Laura , Isak Ilena , Traldi Pietro
Published: May 2012

This review reports the results of some studies carried out by us on the role of pneumatic aspects in electrospray and desorption electrospray surface ionization, with the aim of proposing some relevant aspects of the mechanisms involved in these ionization methods. Electrospray ion sources, with the exception of the nano-electrospray source, operate with the concurrent action of a strong electric field and a supplementary coaxial gas flow. The electric field is responsible for electrospraying of the analyte solution but the use of a coaxial gas flow leads to a significant increase in the analyte signal and allows the use of higher solution flows. However, by employing capillary voltages much lower than those necessary to activate the electrospray phenomenon, analyte ions are still observed and this indicates that different mechanisms must be operative for ion production. Under these conditions, ion generation could take place from the neutral pneumatically sprayed droplet by field-induced droplet ionization. Also, in the case of desorption electrospray ionization, and without any voltage on the spraying capillary as well as on the surface of interest, ions of analytes present on the surface become detectable and this shows that desorption/ionization of analytes occurs by neutral droplets impinging the surface. Consequently, the pneumatic effect of the impinging droplets plays a relevant role and, for these reasons, the method has been called pneumatic-assisted desorption. Some analogies existing between pneumatic-assisted desorption and surface-activated chemical ionization, based on the insertion of a metallic surface inside an atmospheric pressure chemical ionization source operating without corona discharge, are discussed.
Proton Mobility in Water Clusters
Authors: Ryding Mauritz Johan , Andersson Patrik Urban , Zatula Alexey S. , Uggerud Einar
Published: May 2012

Proton mobility in water occurs quickly according to the so-called Grotthuss mechanism. This process and its elementary reaction steps can be studied in great detail by applying suitable mass spectrometric methods to ionic water clusters. Careful choice of suitable core ions in combination with analysis of cluster size trends in hydrogen/deuterium isotope exchange rates allows for detailed insights into fascinating dynamic systems. Analysis of the experiments has been promoted by extensive and systematic quantum chemical model calculations. Detailed low-energy mechanistic pathways for efficient water rearrangement and proton transfer steps, in particular cases along short preformed “wires” of hydrogen bonds, have been identified in consistency with experimental findings.
The Applicability of the Kinetic Method for Measuring Relative Affinities of Macromolecules for Polyatomic Substrates
Authors: Renaud Justin B. , Mayer Paul M.
Published: May 2012

This paper is a review of the kinetic method for the determination of thermochemical values for gas-phase molecules. In addition, we have explored the utility of the kinetic method to obtain meaningful relative binding energies of macromolecules for polyatomic substrates using a system comprising poly(methylmethacrylate) (PMMA) oligomers and doubly protonated diaminoalkanes. The major factors which determined the suitability of the kinetic method for this system were identified as (i) the structural arrangement of the parent ion complex, (ii) possible reverse activation barriers and (iii) the evaluations of A(A S‡). Molecular mechanics/molecular dynamics simulations, together with ion mobility spectrometry, suggests the parent ion complexes represent a relatively equal sharing of the substrate between the two PMMA oligomers within the complex and that the two PMMA oligomers interact almost exclusively with the substrate and not with each other. Tandem mass spectrometry of the trimeric parent complexes resulted in one PMMA unit leaving as a neutral which suggests very limited coulombic repulsion (which would contribute to a reverse activation barrier). The drift times of PMMA–diaminoalkane complexes that were generated directly by electrospray ionization mass spectrometry or by dissociation of a trimeric PMMA–diaminoalkane–PMMA complex were found to be identical and when, combined with molecular mechanics/molecular dynamics simulations, suggested that the product PMMA–diaminoalkane dication has the same conformation as it does when part of a trimeric complex. This is evidence for A(A S‡) ≈ A(A S) and using a statistical mechanics approach, A(A S) ≈ 0. The effective temperature variable in the kinetic method expression was found to decrease as a function of the size of the trimeric complex, suggesting that the population distribution of the dissociating ensemble of complexes narrows as size increases.
Gas-Phase Ion Chemistry and Organic Chemistry: The Story of a Hybrid Six-Sector Mass Spectrometer—The “AutoSpec 6F”
Authors: Gerbaux Pascal , Lamote Luc , Van Haverbeke Yves , Flammang Robert , Brown Jeffery M.
Published: May 2012

The AutoSpec 6F mass spectrometer is a large, floor standing instrument comprising a pair of commercial EBE geometry (AutoSpec) mass spectrometers coupled in series to provide a hybrid EBE–EBE configuration (E and B being, respectively, electrostatic and magnetic sectors.) It was designed in close collaboration between Professor R. Flammang and VG Analytical in Manchester, UK. It is equipped with five collision cells and allows the recording of high-energy collision-induced dissociation (CID), mass analyzed ion kinetic energy spectrometry and neutralization–reionization mass spectrometry data as well as consecutive MSn analyses. The field-free regions between sectors allow the study of unimolecular decomposition products from long-lived metastable ions. The mass spectrometer became even more versatile when a radio frequency-only quadrupole collision cell was installed between the second and the third electric sector. This allows the study of associative ion/molecule reactions in the low kinetic energy regime. Bimolecular chemical reactions were performed inside the quadrupole cell when a neutral reagent was introduced and the reaction products were analyzed by high-energy CID in the downstream sectors. This paper recounts the history and summarizes the capabilities of this versatile instrument.
Interfacing Multistage Mass Spectrometry with Liquid Chromatography or Ion Mobility Separation for Synthetic Polymer Analysis
Authors: Scionti Vincenzo , Katzenmeyer Bryan C. , Erdem Nilüfer Solak , Li Xiaopeng , Wesdemiotis Chrys
Published: May 2012

Synthetic polymers are naturally mixtures of homologs, even in pure form. More complexity is introduced by the presence of different comonomers, end groups and/or macromolecular architectures. The analysis of such systems is substantially facilitated by interfacing mass spectrometry (MS), which disperses based on mass, with an additional level of separation involving either interactive liquid chromatography (LC) or ion mobility (IM) spectrometry, both of which are readily coupled online with electrospray ionization and MS detection. IM-MS separates in the gas phase, post-ionization and, therefore, is ideally suitable for labile and reactive polymers. Its usefulness is illustrated with the characterization of non-covalent siloxane–saccharide complexes, metallosupramolecular assemblies and an air- and moisture-sensitive inorganic polymer, poly(dichlorophosphazene). Conversely, LC-MS which separates in solution phase, before ionization, is most effective for the analysis of polymeric mixtures whose components differ in polarity. Interactive LC conditions can be optimized to disperse by the content of hydrophobic units, as is demonstrated for amphiphilic polyether copolymers and sugar-based nonionic surfactant blends. Both LC-MS and IM-MS can be extended into a third dimension by tandem mass spectrometry (MS2) studies on select oligomers, in order to obtain insight into individual end groups and isomeric architectures, comonomer sequences and degree of substitution, for example, by hydrophobic functionalities.
Time-Resolved Mass Spectrometry for Monitoring Millisecond Time-Scale Solution-Phase Processes
Authors: Rob Tamanna , Wilson Derek J.
Published: May 2012

Many chemical and biochemical reactions equilibrate within a few seconds of initiation under “native” conditions. To understand the microscopic processes underlying these reactions, the most direct approach is to monitor the reaction as equilibrium is established (i.e. the reaction kinetics). However, this requires the ability to characterize the reaction mixture on the millisecond time-scale. In this review, we survey the contributions of time-resolved mass spectrometry (TR-MS) to the characterization of millisecond time-scale (bio)chemical processes, with a focus on biochemical applications. Compared to conventional time-resolved techniques, which use optical detection, the primary advantage of TR-MS is the ability to detect virtually all reactive species simultaneously. This provides a singularly high detail account of the reaction without the need for a chromophoric change on turnover or artificial chromophoric probes. To provide millisecond time-resolution, TR-MS set-ups usually employ continuous-flow rapid mixers, corresponding either to a fixed “tee” that provides a single reaction time-point or an adjustable position mixer that allows continuous reaction monitoring. TR-MS has been used to monitor processes with rates up to 500 s−1 and to provide a detailed account of complex reactions involving 10 co-populated species. This corresponds to significantly lower time-resolution than optical methods, which can measure rates in excess of 900 s−1 under ideal conditions, but substantially more detail (optical studies are typically limited to one or two analytes). TR-MS has been implemented on a number of platforms, including capillary and microfluidic set-ups. Capillary-based implementations are straightforward to fabricate and provide the most efficient rapid mixing. Microfluidic implementations have also been devised to enable multi-step experimental workflows that incorporate TR-MS. As a general method for time-resolved measurements, the applications for TR-MS are wide ranging. TR-MS has been used to identify intermediates in organic reactions, reveal protein (un)folding mechanisms, monitor enzyme catalysis in the pre-steady-state and, in conjunction with hydrogen–deuterium exchange, characterize protein conformational dynamics. While not without limitations, TR-MS represents a powerful alternative for measuring solution phase processes on the millisecond time-scale and a new, promising approach for revealing mechanistic details in (bio)chemical reactions.
Structures and Physical Properties of Gaseous Metal Cationized Biological Ions
Authors: Burt Michael B. , Fridgen Travis D.
Published: May 2012

Metal chelation can alter the activity of free biomolecules by modifying their structures or stabilizing higher energy tautomers. In recent years, mass spectrometric techniques have been used to investigate the effects of metal complexation with proteins, nucleobases and nucleotides, where small conformational changes can have significant physiological consequences. In particular, infrared multiple photon dissociation spectroscopy has emerged as an important tool for determining the structure and reactivity of gas-phase ions. Unlike other mass spectrometric approaches, this method is able to directly resolve structural isomers using characteristic vibrational signatures. Other activation and dissociation methods, such as blackbody infrared radiative dissociation or collision-induced dissociation can also reveal information about the thermochemistry and dissociative pathways of these biological ions. This information can then be used to provide information about the structures of the ionic complexes under study. In this article, we review the use of gas-phase techniques in characterizing metal-bound biomolecules. Particular attention will be given to our own contributions, which detail the ability of metal cations to disrupt nucleobase pairs, direct the self-assembly of nucleobase clusters and stabilize non-canonical isomers of amino acids.
Mass Spectrometry-Based Structural Proteomics
Authors: Serpa Jason J. , Parker Carol E. , Petrotchenko Evgeniy V. , Han Jun , Pan Jingxi , Borchers Christoph H.
Published: May 2012

Structural proteomics is the application of protein chemistry and modern mass spectrometric techniques to problems such as the characterization of protein structures and assemblies and the detailed determination of protein-protein interactions. The techniques used in structural proteomics include crosslinking, photoaffinity labeling, limited proteolysis, chemical protein modification and hydrogen/deuterium exchange, all followed by mass spectrometric analysis. None of these methods alone can provide complete structural information, but a combination of these complementary approaches can be used to provide enough information for answering important biological questions. Structural proteomics can help to determine, for example, the detailed structure of the interfaces between proteins that may be important drug targets and the interactions between proteins and ligands. In this review, we have tried to provide a brief overview of structural proteomics methodologies, illustrated with examples from our laboratory and from the literature.
Bladder cancer: utility of MRI in detection of occult muscle-invasive disease
Authors: Rosenkrantz Andrew B , Mussi Thais C , Melamed Jonathan , Taneja Samir S , Huang William C
Published: May 2012

Background

The presence of muscularis propria invasion by bladder cancer is a key factor in prognosis and treatment decisions, although may be missed by biopsy due to sampling error. MRI has shown potential for detection of muscle invasion but has not specifically been evaluated for this purpose in the setting of bladder cancer patients without evidence of muscle invasion on initial biopsy.

Purpose

To evaluate the role of MRI in detection of muscularis propria invasion by bladder cancer following a pathologic diagnosis of non-invasive tumor.

Material and Methods

This retrospective study included 23 patients who underwent pelvic MRI following a pathologic diagnosis of bladder cancer without muscularis propria invasion and in whom additional histologic evaluation was performed following MRI. Two radiologists in consensus reviewed T2-weighted images to identify those cases suspicious for muscle invasion on MRI. The radiologists identified whether cases suspicious for invasion demonstrated disruption of the T2-hypointense muscularis layer of the bladder wall, peri-vesical fat stranding, and peri-vesical soft tissue nodularity. Findings were compared with pathologic results obtained after MRI.

Results

Suspicion was raised for muscle invasion in eight of 23 cases, four of which exhibited invasion on follow-up pathology. No case without suspicion on MRI exhibited invasion on follow-up pathology. Therefore, sensitivity and specificity were 100% and 79%, respectively. Among individual findings, muscularis disruption on T2WI exhibited sensitivity of 100% and specificity of 79%, peri-vesical fat stranding exhibited sensitivity and specificity of 50% and 84%, and peri-vesical soft tissue nodularity exhibited sensitivity and specificity of 25% and 100%.

Conclusion

MRI demonstrated high sensitivity for detection of muscle invasion in cases of bladder cancer without invasion on initial histologic assessment. Muscularis disruption on T2WI appeared to exhibit a better combination of sensitivity and specificity than did peri-vesical changes.
Additive effect of RET polymorphisms on sporadic medullary thyroid carcinoma susceptibility and tumor aggressiveness
Authors: Ceolin Lucieli , Rodrigues Siqueira Débora , Vaz Ferreira Carla , Romitti Mírian , Cavalcante Maia Silvana , Leiria Leonardo , Crispim Daisy , Ashton Prolla Patrícia , Maia Ana Luiza
Published: May 2012

The authors and the journal apologise for an error in the name of one of the co-authors of this article published in the May 2012 (vol 166, No 5) issue of the European Journal of Endocrinology (pp 847–854). The correct name should be Patrícia Ashton-Prolla and not as published.
Treatment of Maladaptive Aggression in Youth: CERT Guidelines I. Engagement, Assessment, and Management
Authors: Knapp Penelope , Chait Alanna , Pappadopulos Elizabeth , Crystal Stephen , Jensen Peter S. ,   on behalf of the T-MAY Steering Group
Published: May 2012

OBJECTIVE:

To develop guidelines for management and treatment of maladaptive aggression in the areas of family engagement, assessment and diagnosis, and initial management, appropriate for use by primary care clinicians and mental health providers. Maladaptive aggression in youth is increasingly treated with psychotropic medications, particularly second-generation antipsychotic agents. Multiple treatment modalities are available, but guidance for clinicians’ assessment and treatment strategies has been inadequately developed. To address this need, the Center for Education and Research on Mental Health Therapeutics and the REACH Institute convened a steering group of national experts to develop evidence-based treatment recommendations for maladaptive aggression in youth.

METHODS:

Evidence was assembled and evaluated in a multistep process that included a systematic review of published literature; a survey of experts on recommended treatment practices; a consensus conference that brought together clinical experts along with researchers, policy makers, and family advocates; and subsequent review and discussion by the steering committee of successive drafts of the recommendations. The Center for Education and Research on Mental Health Therapeutics Treatment of Maladaptive Aggression in Youth (T-MAY) guidelines reflect a synthesis of the available evidence, based on this multistep process.

RESULTS:

The current article describes 9 recommendations for family engagement, assessment, and diagnosis as key prerequisites for treatment selection and initiation.

CONCLUSIONS:

Recognizing the family and social context in which aggressive symptoms arise, and understanding the underlying psychiatric conditions that may be associated with aggression, are essential to treatment planning.
Off-Label Use of Recombinant Factor VIIa in Pediatric Patients
Authors: McQuilten Zoe K. , Barnes Chris , Zatta Amanda , Phillips Louise E. ,   on behalf of the Haemostasis Registry Steering Committee
Published: May 2012

OBJECTIVE:

To examine off-label recombinant factor VIIa (rFVIIa) use in pediatric patients including clinical indications, dose, adverse events, and outcomes.

METHODS:

All pediatric patients entered into the Haemostasis Registry from 75 participating hospitals were analyzed.

RESULTS:

Three hundred and eighty-eight pediatric patients received off-label rFVIIa from 2003 to 2009. Median age was 12 months (interquartile range 1 month to 11 years). Clinical context included cardiac surgery (52.1%), medical (11.6%), other surgery (10.8%), hematology/oncology (10.3%), trauma (9.3%), intracranial hemorrhage (3.1%), and liver disease (2.8%). Twenty-six patients received extracorporeal membrane oxygenation at the time of rFVIIa administration. Median first dose was 114 μg/kg (interquartile range 90–181; range 7–2250). Thirty-four percent received >1 dose. There was a reduction in usage of red blood cells, platelets, fresh-frozen plasma, and cryoprecipitate in the 24 hours after the first dose for all patients (all P values < .001). Thromboembolic adverse events (TEAs) were reported in 5.4%. No association between TEA and size of first dose was found. Where data were available, 82% of patients were subjectively classified as responding to rFVIIa. Overall 28-day mortality was 27%. In multivariate analysis, pH values before administration and clinical context were independently associated with response to first dose and 28-day mortality.

CONCLUSIONS:

There was a significant reduction in blood product administration after rFVIIa and a subjective response rate of 82%. Both pH and clinical context were associated with response to rFVIIa and mortality. Overall, 5.4% had a TEA reported.
Sensory Integration Therapies for Children With Developmental and Behavioral Disorders
Authors:   SECTION ON COMPLEMENTARY AND INTEGRATIVE MEDICINE,   COUNCIL ON CHILDREN WITH DISABILITIES, Zimmer Michelle , Desch Larry , Rosen Lawrence D. , Bailey Michelle L. , Becker David , Culbert Timothy P. , McClafferty Hilary , Sahler Olle Jane Z. , Vohra Sunita , Liptak Gregory S. , Adams Richard C. , Burke Robert T. , Friedman Sandra L. , Houtrow Amy J. , Kalichman Miriam A. , Kuo Dennis Z. , Levy Susan Ellen , Norwood Kenneth W. , Turchi Renee M. , Wiley Susan E.
Published: May 2012

Sensory-based therapies are increasingly used by occupational therapists and sometimes by other types of therapists in treatment of children with developmental and behavioral disorders. Sensory-based therapies involve activities that are believed to organize the sensory system by providing vestibular, proprioceptive, auditory, and tactile inputs. Brushes, swings, balls, and other specially designed therapeutic or recreational equipment are used to provide these inputs. However, it is unclear whether children who present with sensory-based problems have an actual “disorder” of the sensory pathways of the brain or whether these deficits are characteristics associated with other developmental and behavioral disorders. Because there is no universally accepted framework for diagnosis, sensory processing disorder generally should not be diagnosed. Other developmental and behavioral disorders must always be considered, and a thorough evaluation should be completed. Difficulty tolerating or processing sensory information is a characteristic that may be seen in many developmental behavioral disorders, including autism spectrum disorders, attention-deficit/hyperactivity disorder, developmental coordination disorders, and childhood anxiety disorders.

Occupational therapy with the use of sensory-based therapies may be acceptable as one of the components of a comprehensive treatment plan. However, parents should be informed that the amount of research regarding the effectiveness of sensory integration therapy is limited and inconclusive. Important roles for pediatricians and other clinicians may include discussing these limitations with parents, talking with families about a trial period of sensory integration therapy, and teaching families how to evaluate the effectiveness of a therapy.
Synthesis of Crystalline ZnO Nanosheets on Graphene and Other Substrates at Ambient Conditions
Authors: Vabbina Phani Kiran , Das Santanu , Pala Nezih , Choi Wonbong
Published: May 2012

We report on the fabrication of ZnO nanosheets on Graphene and other substrates at ambient conditions. The growth mechanism and the effect of the substrate are also discussed. Our synthesis method is based on sonochemical reaction of Zinc nitrate hexahydrate and hexamethylenetetramine in aqueous solutions. Extensive analysis by transmission electron microscopy, energy dispersive x-ray spectroscopy (EDS) revealed crystalline ZnO composition of the ZnO nanosheets. The proposed method is a rapid, inexpensive, low-temperature, catalystfree, CMOS compatible and environmentally benign alternative to existing growth techniques.
Low-voltage graphene transistors based on self-assembled monolayer nanodielectrics
Authors: Mattevi Cecilia , Colléaux Florian , Kim Hokwon , Chhowalla Manish , Anthopoulos Thomas D.
Published: May 2012

We demonstrate low operating voltage (<|1.5| V) chemical vapour deposited (CVD) graphene transistors using solution processable organic self-assembled monolayers (SAMs) as nanodielectrics. The transistors show weak extrinsic doping, hysteresis-free operation, low gate-leakage current and good operating stability with bias-stress free characteristics. Most importantly we demonstrate that the Dirac potential can be finely tuned by modifying the molecular end-group of the SAMs without compromising the electrical characteristics of the transistors.
Thermoelastic Dissipation in Composite Silicon MEMS Resonators with Thin Film Silicon Dioxide Coating
Authors: Ghaffari Shirin , Kenny Thomas W.
Published: May 2012

We analyze thermoelastic dissipation in composite silicon MEMS resonators that exhibit multiple mechanical and thermal modes with complex dynamics. Silicon resonators that are coated with thin films of silicon dioxide can have near-zero temperature coefficients of frequency, making them attractive for use as precision time references. The quality factor of MEMS resonators can be dominated by thermoelastic dissipation (TED), which is triggered by the relaxation of mechanically induced temperature gradients. Recently, Chandorkar et al. (2009) have shown an expression of TED based on entropy generation as a weighted sum of the modal solutions of the three-dimensional heat transfer equation. This expression was obtained for weak coupling between mechanical and thermal dynamics. Applying this same technique to a fully coupled solution to the dynamics, we show that the TED contribution of the dominant thermal modes can be inhibited in the presence of a thin silicon dioxide film. Reduction of the contribution from the dominant thermal mode is shown with increasing oxide. We studied the effects of varying oxide film thickness and beam length. The quality factor was simulated for each unique case and compared to multimode energy dissipation. Our results suggest with some variability, thin film oxide coating affects the thermal relaxation of the composite resonator in the direction of lower TED and increased quality factor.
High-Quality, Smooth Fe3O4 Thin Films on Si By Controlled Oxidation of Fe in CO/CO2
Authors: Shi Fengyuan , Xiang Hua , Rzchowski M. S. , Chang Y. A. , Voyles P.M.
Published: May 2012

We fabricated Fe3O4 thin films on TiN buffered Si by CO/CO2 oxidation at 160 °C. The easy saturation of the magnetization at high magnetic field and high resolution scanning transmission electron microscopy (HRSTEM) images show low defect density, smooth Fe3O4 thin films. Oxidation at 400 °C resulted in an undesirable second phase in between the TiN and the un-oxidized Fe, but changes in total gas pressure did not lead to a second phase. The crystal structure of this second phase is similar to Fe2TiO4 (ulvöspinel) from HRSTEM and STEM electron energy loss spectroscopy. Fe3O4 thin films grown at 160 °C follow a power law growth model with an exponent of 0.23±0.03.
Electronic Transport in Organic Ferroelectric Gate Field-Effect Transistors with ZnO Channel
Authors: Yamada Hiroaki , Yoshimura Takeshi , Fujimura Norifumi
Published: May 2012

The electronic transport properties of the organic ferroelectric gate field-effect transistors (FeFETs) with the ZnO channel were investigated. The FeFETs with the channel thickness below 100 nm show nonvolatile operation and the on/off ratio of 105. The field-effect mobility decreased with decreasing the channel thickness. From the Hall-effect measurement, it was found that the Hall mobility increases and the carrier concentration decreases after the deposition of the organic ferroelectric gate. From these results, the effect of the ferroelectric polarization on the electronic transport in the FeFETs was discussed.
Impacts of Temperature and Moisture on the Resistive Switching Characteristics of a Cu-Ta2O5-Based Atomic Switch
Authors: Tsuruoka Tohru , Hasegawa Tsuyoshi , Terabe Kazuya , Aono Masakazu
Published: May 2012

The effects of temperature and moisture on the resistive switching characteristics of oxide-based atomic switches were investigated to reveal their switching mechanism. The observed temperature variations of the SET voltages can be qualitatively explained by the classical nucleation theory. The moisture absorption in oxides results in the formation of a hydrogen-bond network at grain boundaries, and metal ions are likely to migrate along the grain boundaries. Depending on the strength of hydrogen bonds in oxides, the atomic switches exhibit a different switching behavior to ambient conditions.
Synthesis of Resistive Memory Oxides by Ion Implantation
Authors: Bishop S.M. , Rice Z.P. , Briggs B.D. , Bakhru H. , Cady N.C.
Published: May 2012

In this work, we report on the use ion of implantation to synthesize resistive memory oxides. The surface of copper thin films was converted to copper oxide using oxygen implantation. Devices fabricated from the copper oxide (CuxO) layers exhibited unipolar switching behavior without the need for a forming voltage. Technology scaling was demonstrated by oxygen implanting copper damascene vias. Unipolar switching was observed in via-based devices down to 48 nm. The current-voltage data of devices scaled from 100 μm to 48 nm suggests that the RESET transition is related to localized Joule heating. Tantalum oxide (TaxOy) was also created by oxygen implantation but exhibited bipolar resistive switching. Analysis of the conduction suggests that the difference between the two resistance states in these devices is largely due to a lowering of the Pt-TaxOy Schottky barrier.
Firing of a Pulse and its Control Using a Novel Floating Electrode Bi-Resistive Device
Authors: Kang Y. , Verma M. , Liu T. , Orlowski M.
Published: May 2012

A novel resistive device with a floating electrode (RFED) has been manufactured as a stack of layers Cu/TaOx/Pt/TaOx/Cu in a crossbar array comprising two single resistive switches merged antiserially at the common inert Pt floating electrode. The device exhibits four states HRS/HRS, HRS/LRS, LRS/HRS and LRS/LRS, where HRS and LRS are the high and low resistance states, respectively, with only LRS/LRS being fully conductive. When the voltage on one Cu electrode is increased to a value Vth-on(A), a conductive nanofilament (CF) in switch A is formed, while suppressing CF formation in switch B. When the voltage is then extended to negative bias, a sudden jump in the I-V characteristics is observed at Vth-on(B), when the 2nd CF in switch B is formed rendering the RFED device fully conductive. If the current surge just after the formation of CF in 2nd switch exceeds the reset current of the 1st CF, the 1st CF ruptures shortly thereafter, i.e. the conductive state is destroyed as soon as it has been created. This property proves valuable for applications in neural networks where a generation of a current pulse at a critical threshold is required. The height and the time width of the firing pulse is an inherent property of the device and can be controlled by the parameters of the individual switches and their set/reset operations.
Time Voltage Dependency in Resistance Switching TiO2
Authors: Nauenheim Christian , Drouin Dominique , Waser Rainer , Ruediger Andreas
Published: May 2012

Resistively switching TiO2 thin films show a multitude of resistance states, which are achieved during the programming and erasing of a memory cell. These resistance states depend on the applied voltage and the allowed current. Additionally, the operation time has a relevant influence on the adjusted resistance. This parameterization points out a potential application in future multi-level cell memory systems, but also determines the persistence of the non-volatile nature and provides an additional insight into the physics of the resistance switching. Our devices consist of metal-insulator-metal stacks made of Pt/TiO2/Ti/Pt, which are built up in crosspoint junctions. The maximum programming current and the maximum erase voltage amplitude were used to tune in the low resistance and high resistance state, respectively, in combination with the operation time. The corresponding dependencies were determined by quasi-static voltage sweeps, pulse bursts and single pulses of up to 4 V and down to 10 ns.
Electric-Field-Induced Al2O3/3C-SiC Resistance Memory
Authors: Yamaguchi Nobuo , Suda Yoshiyuki
Published: May 2012

We propose a new nonvolatile resistance device having a metal/Al2O3/3C-SiC/n-Si/metal metal-insulator-semiconductor (MIS) structure. It is explained that the electron trapping states are generated in the Al2O3/3C-SiC interface region of the 3C-SiC layer due to partial oxidation of the 3C-SiC near the interface, and that the on and off states of the device are caused by trapping and detrapping of electrons in the defect states through the Al2O3 layer. The electron capture in the defect states causes high electric-field in the oxide layer which results in high-rate electron tunneling through the oxide layer and lowering the device resistance. We have previously reported the similar memory behavior with a metal/SiO2/SiOx/3C-SiC/n-Si/metal MIS structure, however the new memory exhibits more enhanced endurance characteristics than those of the previous memory, where the trapped electrons are injected and ejected through the 3C-SiC layer.
A New, Low Corrosive Fluid to Stimulate Deep Wells Completed With Cr-based Alloys
Authors: Wolf C. A. , Nasr-El-Din H. A. , Bouwman A. , Bang E. R. , Naylor E.
Published: May 2012

Acid treatments of deep wells completed with Cr-based tubulars represent a real challenge to the oil industry. On one hand, Cr-based tubulars are used to protect against CO2 corrosion, but on the other hand, the protective layer (Cr2O3) dissolves in hydrochloric acid (HCl)- a common stimulation fluid. This fact makes protection of Cr tubulars during acidizing very challenging, especially at high temperatures. At temperatures above 200°F, there is a need to add an intensifier. Most of them depend on heavy elements (Cu, Sb), or are not effective above 300°F (e.g., KI).

Over the last decade, we developed a new chelate, glutamic acid N, N-diacetic acid (GLDA) that can dissolve carbonate minerals from carbonate and sandstone formations. This chelate can form worm holes in carbonates (both calcite and dolomite) and does not destabilize clay particles. In the present paper, the corrosion rate of GLDA is compared with other chelates and simple organic acids that are used for carbonate dissolution, such as hydroxyethylethylenediaminetriacetic acid (HEDTA), acetic and formic acid. All corrosion tests were conducted at high temperatures and pressures and extended for up to 6 hour at temperature and pressure. The coupons were examined thoroughly after the tests, and the spent fluid was analyzed for key ions (Cr, Ni, Mo, Fe, and Mn).

The results show that GLDA at 20 wt% gives almost no corrosion with Cr-13 up to 300°F. Unlike GLDA, HEDTA was found to be corrosive at pH=3.8 and requires attention when used in wells completed with Cr-13 based tubulars. On more corrosion resistant Cr-based metals, like super Cr-13 and Duplex the corrosion rate of GLDA is still far below the acceptable limit of 0.02 to 0.05 lbs/ft2 up to 350°F. In wells with corrosive sweet and sour gases tubular consisting of low carbon steel, Cr-based steel or corrosion resistant Cr-Ni alloys can be effectively protected by a combination of GLDA with a minimal amount of corrosion inhibitor. Due to its favorable environmental profile this mixture meets all the OSPAR requirements for use in the North Sea. Based on our results, GLDA solutions can be used to stimulate carbonate and sandstone wells completed with Cr-based tubulars, while maintaining the integrity of the tubulars.
Acoustic Monitor Threshold Limits for Sand Detection in Multiphase Flow Production System
Authors: Odigie M. E. , McLaury B. S. , Shirazi S. A. , Cremaschi S.
Published: May 2012

Solid particle erosion in the oil and natural gas industry can be detrimental to piping and plant equipment, which can lead to production shutdown and other economic losses. Therefore, it is important to be able to detect and quantify the amount of solids present in the piping and plant equipment. This paper presents experimental results obtained using acoustic sand detectors for a broad range of operating conditions at the Tulsa University Sand Management Projects (TUSMP). The effectiveness of sand monitoring in multiphase flow conditions is evaluated and presented. Experimental impingement measurements were performed with acoustic monitors while varying superficial gas and liquid velocities, sand size, and pipe flow orientation. The major focus was to determine the threshold limits for the acoustic sand monitor. Different tests with various velocity combinations to achieve annular, bubble, dispersed-bubble, mist, slug and stratified flow regimes were performed using pipe sizes of 2-inch and 4-inch diameters, and 20 µm, 150 µm and 300 µm sand sizes. The effects of sand size and flow regime on threshold sand rates as sand injection rates change were investigated. The threshold sand rate results for these multiphase flow regimes were determined experimentally and statistical analysis were performed to eliminate the effect of background noise generated when no sand is present in the system. Threshold limits observed for the stratified flow regime was similar and sometimes higher than the ones for annular and slug flows with the slug flow threshold limits being the lowest of all three regimes. Data for other flow regimes like liquid only, bubble and dispersed bubble flows were compared to annular, slug and stratified flow; the highest threshold limit was recorded for liquid only flows closely followed by the limits for bubble flow compared to the other flow types, the smallest threshold limit was recorded for dispersed bubble flow in the horizontal pipe orientation for the flow conditions tested.The threshold sand detection limits for 150 µm and 300 µm sand types are presented and discussed.