bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling of internal and near-nozzle flow of a pintle-type outwards-opening gasoline piezo-injector
Authors: Gavaises M , Tonini S , Marchi A , Theodorakakos A , Bouris D , Matteucci L
Published: December 2006

Computational fluid dynamics (CFD) methods have been used to investigate the internal nozzle flow of an outwards-opening piezo-driven pintle injector designed for spray-guided direct injection gasoline engines. The internal nozzle flow has been investigated for various nozzle designs, with emphasis placed on the effect of manufacturing tolerances on the internal and near-nozzle flow characteristics. The methods employed include features such as moving wall boundaries and time-dependent pressure or flowrate inlet conditions, cavitation as well as Eulerian and Lagrangian near-nozzle and spray models. The results reveal that not only the nozzle internal geometric details and manufacturing tolerances influence significantly the flow conditions at the exit of the pintle injector, but the actual spray characteristics are significantly influenced by the external geometry of the nozzle housing and the pintle shape. The atomization process of the liquid emerging from the pintle nozzle seems to be different from that realized in other nozzle designs used in direct injection gasoline engines; a so-called string-type of spray is formed at the nozzle exit, as confirmed by near-nozzle CCD spray images. The mechanism of string formation is attributed to the limited liquid volume passing through the needle seat area and partly occupying the available volume, while the details of the geometry in this location may enhance local air entrainment. The velocity differences along the circumference of the nozzle exit magnify those flow instabilities and have a predictable effect on the dispersion of the liquid droplets near the nozzle exit.
Instantaneous mass flowrate measurements through fuel injection nozzles
Authors: Ünsal B , Trimis D , Durst F
Published: December 2006

A method of measuring the instantaneous mass flowrates of fuels passing through fast operating injection nozzles is described. The flowrate information is deduced from instantaneous pressure gradient measurements. Through a Fourier transformation, the Fourier coefficients of the pressure gradient are determined, which are used for the calculation of the transient mass flowrate of fuel through injection nozzles, utilizing a special reconstruction algorithm. The theoretical background of the measurement method is provided and the development work to yield a practically applicable measuring system is summarized. The latter is used for verification experiments, providing time-resolved flowrates for a magnetically driven injection valve operating at a pressure of approximately 6 bar. Online measurement of the injection mass flowrates can be recorded with this measuring system and information can be obtained for individual injection events. Cycle-to-cycle variations can be detected in this way.
Effect of piezo-driven and solenoid-driven needle opening of common-rail diesel injectors on internal nozzle flow and spray development
Authors: Lee J W , Min K D , Kang K Y , Bae C S , Giannadakis E , Gavaises M , Arcoumanis C
Published: December 2006

A prototype piezo-driven diesel injector has been developed and characterized in terms of measured flowrate, predicted cavitating nozzle hole flow distribution, and visual spray development. Results are compared with those obtained for a conventional solenoid-driven diesel injector equipped with the same micro-sac multi-hole injection nozzle. The response time and the needle lift trace for both injectors have been predicted for injection pressures up to 1300 bar using a hydraulic simulation model. Mie spray images obtained using a high-speed camera and utilizing diffusion illumination light, have allowed estimation of the spray tip penetration and spray cone angle under a variety of back pressures. The experimental results show that the piezo-driven injector produces longer spray tip penetration and smaller spray cone angle. This has been supported by CFD simulations of the internal nozzle hole cavitating flow obtained using the transient needle profile of the solenoid- and the piezo-driven injectors. Model predictions suggest an increase in the fuel exit momentum of the piezo-driven nozzle during the opening phase of the needle, relative to those of the solenoid-driven one.
A numerical and experimental study of the squish-jet combustion chamber
Authors: Lappas P , Evans R L
Published: December 2006

The fluid flow characteristics near top dead centre (TDC) were numerically simulated for three different combustion chambers designed to generate squish flow and enhance turbulence generation in spark ignition engines. One of the combustion chambers was a plain bowl-in-piston type while the remaining two were different configurations of the squish-jet chamber, which has a unique geometry for forming jets that converge radially inwards as TDC is approached. The computational fluid dynamics (CFD) code KIVA-3V was used to produce the simulations and particular attention was given to mean velocities and turbulent fluctuations near TDC. The flow fields were measured experimentally (with particle image velocimetry (PIV) and laser Doppler velocimetry (LDV)) in a unique rapid-intake and compression machine, and compared with the output from the KIVA-3V code. The use of the rapid-intake and compression machine enabled the initial conditions to match exactly those in the KIVA-3V calculations, thus reducing uncertainty in the validation study. The study led to a greater understanding of the flow processes inside these complex combustion chambers and the results showed that squish-jet chambers tend to generate higher peak turbulence levels than do plain bowl-in-piston chambers, even though they may generate lower mean squish velocities. From this perspective, the KIVA code can be a useful tool for designing squish-jet combustion chambers. The study also showed that KIVA-3V predicted downstream squish jet velocities well. Nevertheless, the squish-jet velocities at the piston bowl rim were overestimated and the specific turbulent kinetic energy ( k) and its dissipation ( e) appear to have been overestimated during much of the compression period tested.
Real-time measurement of equivalence ratio using laser-induced breakdown spectroscopy
Authors: Ferioli F , Buckley S G , Puzinauskas P V
Published: December 2006

This paper demonstrates the use of laser induced breakdown spectroscopy (LIBS) as a diagnostic technique to obtain optical measurements of equivalence ratio in a sparkignited engine. Point measurements were obtained in the exhaust manifold of an automotive engine close to the exhaust port of a cylinder. The experimental apparatus was synchronized with the engine in order to obtain measurements in a fixed position during the cycle. Eighty-shot averaged measurements of equivalence ratio P, obtained in under 10 s, were shown to have ΔP = ±0.05 (95 per cent confidence interval). Single-shot measurements were hindered by noise in the signal, but it is shown that the statistical technique of principal component analysis can significantly improve the precision of the data and allows discrimination between measurements obtained in lean, stoichiometric, and rich conditions. The data presented represent one of the first applications of LIBS to optical measurements of the equivalence ratio in an engine, and considerable improvements are expected with further study.
Spray and combustion visualization of a direct-injection diesel engine operated with oxygenated fuel blends
Authors: Alam M , Song J , Zello V , Boehman A
Published: December 2006

Experiments were conducted with a commercially available six-cylinder water-cooled turbocharged direct-injection diesel engine. The cylinder head was modified to permit access to the combustion chamber with an engine videoscope. The engine was operated with base diesel fuel (BP-15) and other blends, base diesel with 20 wt% biodiesel (B-20) and with 20wt% diglyme (O-20). A neat biodiesel (B-100) and a 95 wt% blend of diglyme with base diesel fuel (O-95) were also considered. These fuels were used for observing the effect of the fuel properties on injection timing, heat release, flame structure, and luminosity. All the tests were performed with the engine operated at light load (61 N m, 10 per cent of the rated load) and 1800 r/min. Visualization showed that the start of injection occurred 0.4° earlier with B-100 than with BP-15. B-100 showed the earliest start of injection among the fuels. An earlier start of injection was also observed with B-20 and O-20 blends compared with BP-15 fuel. Combustion analysis showed a lower premixed combustion heat release rate with the diglyme blends compared with the B-20, B-100, and BP-15. The highest premixed burn peak and the lowest premixed burn peak were observed with BP-15 and O-95 fuels respectively. It is difficult to distinguish between the spray flames of BP-15, B-20, B-100, and O-20. However, with much higher oxygen content in the O-95 fuel the natural luminosity of the flame was too faint for detection with the camera. The combination of combustion analysis and in-cylinder visualization employed in this study provides a unique opportunity to understand how oxygenates behave in a commercial engine.
Numerical investigations of piston cooling using oil jet in heavy duty diesel engines
Authors: Agarwal A K , Varghese M B
Published: December 2006

Thermal loading of diesel engine pistons has increased dramatically in recent years owing to applications of various technologies to meet low emission and high power density requirements. Control of piston temperatures by cooling of these pistons has become one of the determining factors in a successful engine design. The pistons are cooled by oil jets fired at the underside from the crankcase. Any excessive piston temperature rise may lead to engine seizure because of piston warping. However, if the temperature at the underside of the piston, where the oil jet strikes the piston, is above the boiling range of the oil being used, it may contribute to the generation of mist. This mist significantly contributes to the non-tailpipe emissions in the form of unburnt hydrocarbons (UBHCs). The problem of non-tailpipe emissions has unfortunately not been looked into so seriously, as the current stress of all automobile manufacturers is to meet the tailpipe emission legislative limits.

A numerical model has been developed using finite element methods for studying the oil jet cooling of pistons and has been validated experimentally on a flat plate cooled by oil jet. Using numerical modelling, the heat transfer coefficient (h) at the underside of the piston is predicted. This predicted value of heat transfer coefficient significantly helps in selecting the correct oil type, oil jet velocity, oil jet diameter, and distance of oil nozzle from the underside of the piston. It also helps to predict whether the selected grade of oil will contribute to mist generation. Isotherms of the predicted temperature profiles in a production grade piston have been plotted.
Wave-current interactions in marine current turbines
Authors: Barltrop N , Varyani K S , Grant A , Clelland D , Pham Xuan
Published: December 2006

The influence of waves on the dynamic properties of bending moments at the root of blades of tidal stream vertical-axis rotors is reported. Blade element-momentum theory for wind turbines is combined with linear wave theory and used to analyze this influence. Experiments were carried out with a 350 mm diameter rotor to validate the simulation and the comparison shows the ability of the theoretical approach to predict the blade root bending moments. It can be concluded that, in steep waves, linear theory underestimates the dynamic behaviour of bending moments. However, in long waves, linear theory works well. Bending moments at roots of rotor blades fluctuate with significant amplitudes (as much as 50 per cent of mean value for out-of-plane bending moment and 100 per cent of mean value for in-plane bending moment), which will be important for design of tidal stream rotors.
Tidal current energy extraction: Hydrodynamic resource characteristics
Authors: Couch S J , Bryden I
Published: December 2006

There is an apparent lack of understanding of the tidal resource and its response to harvesting of energy among the principal proponents of the fledgling UK tidal energy industry: the device developers, principally supported by government funding. The authors' intent is to widen understanding of the different hydrodynamic conditions and controls that generate favourable conditions for tidal energy extraction. This paper outlines the generic hydrodynamic conditions that typically provide the most important fundamental requirement for harvesting tidal energy, namely, a large tidal current resource. Five generic tidal regimes are presented, and the suitability of each regime for harvesting of energy is considered. Of the five regimes, two cases are identified as being most prevalent, but are generally unsuitable for economic exploitation. Understanding the significant differences between the driving mechanisms of each of the flow regimes is therefore key to effective site selection for large-scale development. Furthermore, the response of the different regimes to energy extraction from the system is not consistent, further impacting on site selection. Numerical simulations of idealized examples highlighting the different hydrodynamic conditions in operation will be used to support descriptions of the relevant tidal flow regimes.
Theoretical and experimental investigation of wave energy conversion by a phase-controlled heaving body
Authors: Falnes J , Bjarte-Larsson T
Published: December 2006

Two phase-control methods for maximizing converted energy, optimum reactive control and sub-optimum latching control, are compared, and also numerically discussed for a heaving semisubmerged sphere. For a sphere of 10 m diameter and an incident sinusoidal wave of 9 s period and 0.5 m elevation amplitude, the maximum time-average absorbed power is 172 kW, 137 kW, and 24 kW for the cases of reactive control, latching control, and no phase control, respectively. With latching control, the need for reversing energy flow, during parts of each heave cycle, is avoided. For a more practically shaped axisymmetric body, a cylinder with a hemispherical bottom, numerical results for the radiation resistance are quantitatively compared with experimental results, by application of approximate semi-empirical elementary function formulae. Performed laboratory model experiments with such an axisymmetric body, which heave resonates with a wave of frequency 1.1 Hz, demonstrate that, compared to no phase control, latching control results in an appreciable increase of energy capture from waves of frequency 0.75 Hz and 0.5 Hz. Moreover, experiments indicate the need for developing a low-friction vertical guiding system for the heaving body.
Mooring design approach for wave energy converters
Authors: Johanning L , Smith G H , Wolfram J
Published: December 2006

To be effective, wave energy converter devices (WECs) must be installed in unsheltered locations with high wave energy density. Such regimes are more likely to be at offshore locations and much current interest is focused on offshore floating devices. Since the wave energy industry has little practical long-term experience with deployed WEC systems there is no historical experience upon which to base the formulation of appropriate station-keeping arrangements. The development of generic station-keeping arrangements that will allow reliable, yet cost-effective, mooring systems presents a challenging task. This paper raises issues pertinent to the station-keeping of floating WECs and discusses a preliminary design procedure to identify suitable mooring arrangements.
Fabrication of three-dimensional hybrid nanostructures by an integrated process comprising nanoimprint lithography and layer-by-layer assembly
Authors: Huskens J , Maury P , Crespo-Biel O , Péter M , Reinhoudt D. N.
Published: December 2006

The fabrication of three-dimensional (3D) nanostructures, which have sub-100 nm dimensions in all three directions that can be changed independently for each dimension, is a key issue of nanotechnology. E-beam writing can provide high-resolution two-dimensional (2D) nanopatterns, but implementation of pattern replication methods for rapid reproduction of a master and self-assembly, to provide patterned growth of structures, is essential for the development of more general and versatile 3D nanofabrication methodologies. Here the integration of top-down nanoimprint lithography (NIL) and bottom-up layer-by-layer self-assembly (LBL-SA) are described for the preparation of 3D hybrid nanostructures. NIL provided down to sub-100nm poly(methylmethacrylate) (PMMA) structures. These were employed to fabricate patterned self-assembled monolayers of cyclodextrin (CD) host molecules on silicon oxide. The consecutive LBL-SA with adamantyl guest-functionalized dendrimers and CD-modified gold nanoparticles resulted in patterned multilayer structures with thicknesses of 3-30 nm. The x, y control by NIL and the z control (albeit the same height for all nanostructures simultaneously) by LBL-SA ultimately allowed the fabrication of circular structures with a radius of 25 nm and a thickness of 20 nm. The integration of the two methods has thus yielded a versatile 3D nanofabrication methodology comprising 10-40 process steps.
Numerical modelling for atomic-force-microscopy-based impedance imaging
Authors: Polydorides N , Kyprianou A , Charalambous C. D.
Published: December 2006

This paper is motivated by the pioneering work of O'Hayre et al. and of Kalinin and Bonnell who brought together the imaging modalities of atomic force microscopy (AFM) and electrical impedance spectroscopy. With the intention to assist in the further development of AFM-impedance imaging by enhancing its quantitative spatial resolution, a numerical model is provided on the basis of a finite element method which can be used to simulate the impedance measurements. The model facilitates the contact impedance at the interface between the tip of the atomic force microscope's cantilever and the upper surface of the sample. Based on this model, a formula is derived for the linearized sensitivity of the measurement as a spatial function that relates the value of electric potential recorded at the tip to the electrical properties of the sample underneath it. The performed numerical simulations suggest that the sensitivity functions of adjacently captured impedance measurements overlap, and this introduces linear dependences in the acquired data, ultimately reducing the spatial resolution of the reconstructed image.
Impact of size-dependent non-local elastic strain on the electronic band structure of embedded quantum dots
Authors: Zhang X , Sharma P
Published: December 2006

The effect of mechanical strain on the quantum confinement properties of quantum dots is appreciable and both qualitative and quantitative description of the electronic band structure of quantum dots requires proper incorporation of its effect. Although atomistic calculations such as tight binding or pseudopotential approaches are viable options, the typical and ‘standard’ practice is to employ the coarse-grained multiband envelope function method to compute the band structure of both strained and unstrained quantum dots. The typical recipe involves calculation of strain based on classical continuum elasticity and a subsequent link to the aforementioned eight-band envelope function model. The mechanical strain predicted by classical elasticity is not only size-independent but also departs qualitatively from the actual (atomistic) field owing to neglect of non-local effects that are prevalent at the nanoscale. In the present work, the authors employ the strain as calculated from a size-dependent non-local theory of elasticity (presented in work previously published by the current authors) and assess the qualitative and quantitative effects on the electronic band structure of an InAs-GaAs quantum dot system. Quantitatively, deviations of band gaps in the range of 100 meV are found when compared to classical elasticity-based estimates, while no significant qualitative differences were found. The non-local elastic effects, however, are appreciable only for very small quantum dots and certain materials (such as the InAs-GaAs system discussed in the present work).
Catalytic Direct Arylation of Heteroaromatic Compounds
Authors: Satoh Tetsuya , Miura Masahiro
Published: December 2006

The direct intermolecular arylation reactions of heteroaromatic compounds such as pyrroles, furans, thiophenes, azoles, and pyridines with aryl halides using palladium or rhodium catalysts have significantly been developed as effective, straightforward methods for making aryl–heteroaryl linkages, which are often found in biologically active compounds and π-conjugated functional materials. In this article is summarized the recent progress in this field.
A Correlation between pH and Fluorescence Lifetime of 2′,7′-Bis(2-Carboxyethyl)-5(6)-carboxyfluorescein (BCECF) In Vivo and In Vitro
Authors: Nakabayashi Takakazu , Wang Hui-Ping , Tsujimoto Kazuo , Miyauchi Seiji , Kamo Naoki , Ohta Nobuhiro
Published: December 2006

The pH dependence of the fluorescence lifetime of BCECF both in solution and in intact cells of Halobacterium salinarum has been measured with time-resolved fluorescence spectroscopy. A correlation between pH and fluorescence lifetime in vivo is different from that in vitro. The difference is ascribed to the local field produced by some protein membrane in a biological system.
Effect of Steric Barrier on the Shuttling of Rotaxane Having Crown Ether Wheel
Authors: Kihara Nobuhiro , Koike Yoshifumi , Takata Toshikazu
Published: December 2006

Rotaxanes comprising dibenzo-24-crown-8 and a symmetrical ammonium salt were desymmetrized by N-acylation. The shuttling behavior was investigated in detail. For the N,N-di-n-alkyl-type axle, the propionyl group was necessary to stop shuttling, whereas the acetyl group was bulky enough for the N,N-dibenzyl-type axle. According to the ΔS‡ term of the shuttling, the N-formyl and N-acetyl rotaxanes with an N,N-di-n-alkyl-type axle showed similar shuttling frequencies at room temperature.
Electrochemiluminescence-based DNA Detection Using Guanine Oxidation at Electrostatic Self-assembly of Ru(bpy)32+-doped Silica Nanoparticles on Indium Tin Oxide Electrode
Authors: Wei Hui , Wang Erkang
Published: December 2006

A Ru(bpy)32+-doped silica nanoparticle- [Ru@Silica] modified indium tin oxide electrode was prepared by simple electrostatic self-assembly technique, and one-electron catalytic oxidation of guanine bases in double-strand and denatured DNA was realized using the electrochemiluminescence detection means.
Synthetic Application of PVP-stabilized Au Nanocluster Catalyst to Aerobic Oxidation of Alcohols in Aqueous Solution under Ambient Conditions
Authors: Tsunoyama Hironori , Tsukuda Tatsuya , Sakurai Hidehiro
Published: December 2006

Gold nanoclusters (φ = 1.3 nm) stabilized by poly(N-vinyl-2-pyrrolidone) (Au:PVP) were found to show a high catalytic activity toward the aerobic oxidation of alcohols. Various kinds of primary and secondary alcohols were converted to the corresponding carboxylic acids and ketones, respectively, in basic aqueous media at 300–360 K under air.
Chemical Intertransformations of Diverse Bisdesmosidic Furostanol Saponins
Authors: Zhao Dong-Mei , Liu Yang , Liu Yong-Xiang , Zheng Li-Gang , Yan Mao-Cai , Cheng Mao-Sheng
Published: December 2006

An effective synthetic route towards four types of bisdesmosidic furostanol saponin was developed and 36 derivatives were designed and synthesized for antitumor investigation. The chemical intertransformations of these furostanol structures were discussed with respect to the E ring.
Electrochemical Evaluation of Hydrogen Bond Donor Ability of Sulfonylurea Molecules by Cyclic Voltammetry
Authors: Kawasaki Kazunori , Sakakibara Kazuhisa
Published: December 2006

Hydrogen bond donor ability, which is an essential factor for strong black color developing and its durability on the thermal paper, of the sulfonylurea (color developer) can be evaluated well in terms of the reduction potential for the leuco dye and the sulfonylurea system in DMF by cyclic voltammetry.
High Current Density Bioelectrolysis of d-Fructose at Fructose Dehydrogenase-adsorbed and Ketjen Black-modified Electrodes without a Mediator
Authors: Kamitaka Yuji , Tsujimura Seiya , Kano Kenji
Published: December 2006

d-Fructose dehydrogenase (FDH) has been irreversibly adsorbed without loss of the enzymatic activity on Ketjen black (KB)-modified glassy carbon electrodes, although the adsorption rate is very slow probably owing to the microstructure of KB. The FDH-adsorbed electrode produced the enzyme-kinetic-controlled catalytic oxidation wave of d-fructose at current densities of as high as 10 mA cm−2 without a mediator, in which the electron in FDH seems to be directly transferred to the electrode via the heme c site. No hindrance was observed in the mass transfer of d-fructose to KB-modified electrodes.
Enantioselective Permeability through Membranes from a Poly(substituted phenylacetylene) Having a Chiral Helical Backbone and Achiral Bidentate Ligands as Pendant Groups
Authors: Hadano Shingo , Teraguchi Masahiro , Kaneko Takashi , Aoki Toshiki
Published: December 2006

A chiral helical poly(phenylacetylene) bearing N-(2-hydoroxyethyl)aminomethyl groups as ligand sites was synthesized by helix-sense-selective polymerization. In the obtained polymeric membrane, the ligands could complex with Cu2+. In permeation of aqueous solution of racemic phenylalanine, enantioselectivity in permeation through the Cu2+ complexing membrane was about 3 times higher than that of the original membrane.
Synthesis of N-(3-Arylmethyl-2-oxo-2,3-dihydroimidazo[1,2-a]pyridin-3-yl)benzamides
Authors: Tu Shujiang , Zhang Junyong , Jia Runhong , Jiang Bo , Zhang Yan , Yao Changsheng , Jiang Hong
Published: December 2006

A new series of imidazo[1,2-a]pyridin-2-one derivatives were synthesized by the reaction of 4-arylidene-2-phenyl-5(4H)-oxazolones and pyridin-2-amine under microwave irradiation in ethylene glycol. The starting materials were easily obtained and the operation was very convenient.
Palifermin: Role in the Prevention of Chemotherapy- and Radiation-Induced Mucositis
Authors: McDonnell Anne M , Lenz Kristi L
Published: December 2006

Objective:

To assess the efficacy, toxicity, and potential cost benefit of palifermin in the prevention of chemotherapy- and radiation-induced mucositis.

Data Sources:

MEDLINE and PubMed database searches were conducted (1966–May 2006) using the following search terms: palifermin, human keratinocyte growth factor, fibroblast growth factor, mucositis, and stomatitis.

Study Selection And Data Extraction:

All published clinical trials and abstracts examining the use of palifermin, as well as information from the manufacturer, were included.

Data Synthesis:

Severe mucositis resulting from anticancer therapies increases healthcare expenditures and negalively impacts patients' quality-of-life. Radiation therapy to the head and neck, as well as stem cell transplant conditioning regimens, have the highest incidence of severe mucositis. Consequences include prolonged hospitalization, need for parenteral nutrition, increased risk of infection, and severe pain. Palifermin is a recombinant human keratinacyte growth factor indicated in patients with hematologic malignancies who are undergoing stem cell transplant. In a randomized, placebo-controlled, Phase III trial, palifermin significantly reduced the incidence and duration of severe mucositis and days of parenteral nutrition and opioid analgesics in patients undergoing autologous stem cell transplant. The most common adverse effects of palifermin were rash, pruritus, cough, and taste alterations. Data in patients with solid tumors are limited, and there is a theoretical risk of stimulating tumor growth.

Conclusions:

Treatment with palifermin appears to decrease the severity and duration of severe mucositis following autologous stem cell transplant. Use in these patients appears justified: however, use in non-stem cell transplant patients should bo discouraged until more efficacy and toxicity data are available.
Brand Versus Generic Alendronate: Gastrointestinal Effects Measured by Resource Utilization
Authors: Halkin Hillel , Dushenat Marina , Silverman Barbara , Shalev Varda , Loebstein Ronen , Lomnicky Yosef , Friedman Nurit
Published: December 2006

Background:

Adverse reactions related to the upper gastrointestinal tract (UGIT) that are associated with generic alendronate formulations may differ from those associated with the brand drug.

Objective:

To test the hypothesis that adverse UGIT effects of alendronate formulations may differ between generic and brand products.

Methods:

We conducted a database health resource utilization analysis of UGIT outcomes in patients who started treatment with generic or brand alendronate formulations during 2001–2005. We included 6962 patients who were treated continuously for 3 months with 1 of 4 alendronate formulations: brand 10 mg/day (Merck, Sharpe & Dohme, n = 1418), generic A 10 mg/day (Teva, Israel, n = 650), generic B 10 mg/day (Unipharm, Israel, n = 628), and brand 70 mg/wk (n = 4266). In these patients, who had neither filled a prescription for alendronate nor had any gastrointestinal problems in the year preceding the study, we compared incidence rates of new use of gastric medications (H2-blockers, proton-pump inhibitors, or antacids), gastroenterology visits, endoscopies, and hospital admissions.

Results:

Incident rate ratios (IRR) for treatment discontinuation were higher with both daily generic products (IRR 1.3; 95% CI 1.04 to 1.63). Adherence (medication possession ratio [MPR] >80%) was better with brand 10 mg/day (IRR 1.19; 95% CI 1.11 to 1.27). All comparisons were adjusted for use of concurrent corticosteroids, nonsteroidal antiinflammatory drugs, and potassium supplements. Hospitalization rates (2.7-3.2%) were similar in all groups. New use of gastric medications (3.4–4.9%) was lower with brand 10 mg/day (IRR 0.71; 95% CI 0.53 to 0.95). Rates of UGIT endoscopy (n = 49) in patients receiving 10 mg were 0.6% (brand), 1.1% (generic A), and 1.6% (generic B), with generic B higher (IRR 2.88; 95% CI 1.14 to 7.29) in the entire cohort, but not among new users (n = 273) of gastric drugs (IRR 2.46; 95% CI 0.55 to 11.05). Endoscopic findings were normal in 22 patients, hiatal hernia with no mucosal lesion was present in 10 patients, and there was mild-to-moderate esophagitis or gastritis in 17 patients; there were no significant differences among the formulations.

Conclusions:

We found insufficient evidence to indicate major differences in UGIT adverse effects related to use of daily generic, as compared with brand, alendronates.
Oral Varenicline for Smoking Cessation
Authors: Zierler-Brown Seena L , Kyle Jeffrey A
Published: December 2006

Objective:

To review the pharmacology, pharmacokinetics, efficacy, and safety of varenicline and provide a review of relevant clinical data.

Data Sources:

A MEDLINE search (2001–December 2006) was conducted using the key words varenicline and nicotine replacement therapy for clinical trials limited to human subjects and published in English.

Study Selection And Data Extraction:

All available human trials of varenicline were selected for review. References cited in identified articles were used for additional citations.

Data Synthesis:

Varenicline selectively targets the α4β2 nicotine receptors in the brain that are responsible for cravings and withdrawal associated with nicotine use and dependence. Maximal plasma concentration occurs within 3–4 hours after administration and, after multiple doses, a steady-state concentration is reached within 4 days. Varenicline has a half-life of 24 hours. Oral bioavailability is not affected by food or time of administration. It exhibits linear pharmacokinetics and tow plasma protein binding (≤20%) regardless of a patient's age and renal status. It can be administered once daily. Dosage adjustments are not required in patients with hepatic insufficiency, but adjustments may be necessary in patients with severe renal insufficiency. Clinically significant drug–drug interactions have not been observed with varenicline or co-inhibitors of the human organic cation transporter, which mediates renal secretion of varenicline. Substrates such as warfarin, digoxin, cimetidine, metformin, bupropion, and transdermal nicotine do not alter pharmacokinetic parameters when coadministered with varenicline. In vitro studies have not demonstrated alterations in cytochrome P450 enzyme parameters. Varenicline's safety with coadministration of nicotine replacement products has not been well established.

Conclusions:

Varenicline is an effective oral agent for smoking cessation.
Botulinum Toxin a in the Treatment of Sialorrhea
Authors: Benson Jennifer , Daugherty Kimberly K
Published: December 2006

Objective:

To review the efficacy and safety of botulinum toxin A (BTX) in the treatment of sialorrhea.

Data Sources:

A PubMed search and reference list review was performed to find clinical trials on BTX in the treatment of sialorrhea. The search was limited to English-language trials involving human subjects. Articles from 1965 to October 2006 were searched, using key words botulinum, botulinum toxin, Botox, sialorrhea, saliva, salivary gland, and drooling.

Study Selection And Data Extraction:

Reports of 15 studies were found on BTX in the treatment of sialorrhea in human subjects. Four controlled trials are presented in detail, and 11 uncontrolled studies are summarized.

Data Synthesis:

One controlled trial found that BTX caused significant reductions in patients' severity and frequency of drooling compared with placebo. Another found significant saliva reductions in the treatment group receiving the highest dose of BTX but found no subjective improvement compared with the placebo group. A third study comparing BTX with placebo found significant improvements in subjective and objective measures of drooling in the treatment group. A fourth controlled trial found significant reductions from baseline levels of drooling after patients received BTX injections. Similar efficacy was found between the BTX and scopolamine treatment groups.

Conclusions:

Evidence indicates that BTX is a safe and effective treatment for sialorrhea. More research is needed to determine the ideal dose, injection location, and technique of BTX injections.
Infants' knowledge of the path that animals take to reach a goal
Authors: Rakison David H. , Cicchino Jessica B. , Hahn Erin R.
Published: December 2006

Two experiments with the inductive generalization procedure tested whether 16‐ and 20‐month‐old infants understand that animals and not vehicles follow a rational path to reach a goal. Infants were tested with four different events and the model exemplar was either an animal or ambiguous block. Results showed that infants at 20 months of age, but not those at 16 months of age, understand that animals follow rational paths to reach a goal. However, 20‐month‐olds require the presence of static perceptual cues to apply a teleological interpretation to animals' actions.
Development of gaze aversion: Qualitative changes over the early school years
Authors: Doherty‐Sneddon Gwyneth , Phelps Fiona , Clark Julia
Published: December 2006

Looking away from an interlocutor's face during demanding cognitive activity can help adults and children answer challenging mental‐arithmetic and verbal‐reasoning questions (Glenberg, Schroeder, & Robertson, 1998; Phelps, Doherty‐Sneddon, & Warnock, 2006). Whilst such ‘gaze aversion’ (GA) is used far less by 5‐year‐old schoolchildren, its use increases dramatically during the first years of primary education, reaching adult levels by 8 years of age (Doherty‐Sneddon, Bruce, Bonner, Longbotham, & Doyle, 2002). The current study investigates whether developmental changes also occur in a qualitative aspect of GA – the direction of movement involved in GA shifts. Video data from eighteen 5‐year‐olds and nineteen 8‐year‐olds answering verbal and arithmetic questions were analysed for direction of GA. We found very different profiles of direction of GA across the two ages: whilst the 5‐year‐olds used predominantly rapid multidirectional ‘flicking’ movements and some sustained left lateral movements, the 8‐year‐olds used predominantly sustained rightward movements. It is concluded that there are concomitant qualitative changes in the nature of GA shifts as well as quantitative increases in the use of GA across these age groups. A model of human attention in face‐to‐face interaction is discussed, as are implications for the assessment of children's learning and development.
A Commentary on Psychosocial Interventions and Evidence-Based Practice: Time for Reflection About What an ‘Ideal’ Psychosocial Intervention Would Look Like in Clinical Psychology?
Authors: King Neville J. , Ollendick Thomas H.
Published: December 2006

Controlled efficacy/effectiveness trials throughout the world have reached a high standard from a methodological stance, but what do we regard as the ideal or elegant intervention in clinical psychology? This article presents six key points as the gold standards of psychosocial interventions by which treatment efficacy/effectiveness research with children, adolescents and adults might be evaluated: (1) theoretical rationale and conceptualisation of clinical dysfunction, (2) clear problem identification and target client group, (3) program features such as realistic goal setting, flexibility, and time-limited interventions, (4) manual-based treatments, (5) research support including clinically significant outcomes, and (6) acceptability/social validation of clients and society. Finally, we discuss the usefulness of such a framework for mental health professionals and clinical researchers.
Rumination and Experiential Avoidance in Depression
Authors: Cribb Gemille , Moulds Michelle L. , Carter Sally
Published: December 2006

Recent investigations have demonstrated a renewed interest in the role of avoidance in depression; however, little is known of which specific forms of avoidance — cognitive, behavioural or experiential — are important in this context. This study examined (a) the relationship between depression, rumination and these subtypes of avoidance, and (b) the proposal that the abstract/analytical nature of ruminative thought is linked to experiential avoidance. A nonclinical sample (N = 101) of undergraduate students completed self-report measures of depression, rumination, avoidance and mood state and viewed a low mood emotion-eliciting video stimulus. Participants' written summary of the film clip was independently rated for the degree to which it was abstract or concrete. Rumination, depression and cognitive, behavioural and experiential avoidance were all significantly correlated and remained so when anxiety was controlled. Further, reduced concreteness of description of the film clip was associated with experiential avoidance and rumination. Taken together, the findings underscore the value of clinicians being attentive to experiential avoidance in the assessment and treatment of depression.
The Effects of Diagnostic Labelling on the Implicit Theories of Attention-Deficit/Hyperactivity Disorder Held by Health Professionals
Authors: Dryer Rachel , Kiernan Michael J. , Tyson Graham A.
Published: December 2006

Attention-deficit/hyperactivity disorder (ADHD) is the most recent diagnostic label used to describe a behavioural condition of which the essential features are developmentally inappropriate levels of inattention, impulsivity and overactivity. ADHD has attracted both controversy and attention from the professional and scientific community. However, little is known regarding the explanatory models (implicit theories) of health professionals or of their beliefs regarding the treatment of this condition, specifically the impact of diagnostic labelling on their decisions concerning treatment. This study manipulated the presence versus absence of the diagnostic label ‘ADHD’ in a vignette study describing the symptoms of this condition. The vignette was presented to professionals in the educational, mental health and allied health fields. After reading the vignette, participants were required to complete a questionnaire examining implicit beliefs concerning ADHD. The results confirmed that the presence of the diagnostic label (ADHD) changed the causal explanations by professional groups. However, the presence of the diagnostic label did not significantly change the beliefs about the optimal treatment strategy for this condition.
Deliberate Self-Harm: Have We Scratched the Surface?
Authors: Cumming Steve , Covic Tanya , Murrell Elizabeth
Published: December 2006

This article presents the current state of knowledge in deliberate-self harm (DSH). DSH presents as a comorbidity with a number of personality disorders and psychopathologies, but is also relatively common in the psychologically healthy population. Over the past 10 years, attention has shifted from the investigation of DSH as a cardinal or comorbid symptom of psychopathology to an attempt to understand the behaviour itself, without reference to other psychopathological processes. It is argued that this development in understanding the aetiology of DSH has not been matched by developments in treatment or management of DSH, with the majority of treatment programs targeting larger syndromes of which DSH is a symptom. Treatment regimes aimed at reducing DSH appear to be either untested or demonstrably unsuccessful.
Manualised Cognitive–Behavioural Therapy in the Intensive Treatment of Adolescent Obsessive–Compulsive Disorder
Authors: Savva Danay , Rees Clare
Published: December 2006

This article offers a preliminary investigation of the delivery of an intensive version of manualised cognitive–behavioural therapy for adolescent obsessive–compulsive disorder (OCD). The aim was to address issues of treatment accessibility within the area, including a shortage of therapists who feel competent and possess the expertise to successfully deliver these protocols. Two male adolescents, with a principal diagnosis of OCD, participated in eight weekly 150-minute sessions. A series of diagnostic, symptom severity, global functioning, and self-report measures were completed at pretreatment, across treatment weeks, at posttreatment, and at 6-week follow-up. Further, monitoring of multiple baselines across behaviours for each adolescent across treatment weeks served to extend results beyond mere end points. Process issues specific to each adolescent, his family, and the therapeutic relationship were considered. Along with the overall outcome results, such information aimed to provide useful data for clinicians interested in implementing the program. Reductions in OCD symptomology and symptom severity for both participants at posttreatment and at 6-week follow-up suggest that an intensive format of treatment delivery might benefit some adolescents.
Phase Precession in Hippocampal Interneurons Showing Strong Functional Coupling to Individual Pyramidal Cells
Authors: Maurer Andrew P. , Cowen Stephen L. , Burke Sara N. , Barnes Carol A. , McNaughton Bruce L.
Published: December 2006

Although hippocampal interneurons typically do not show discrete regions of elevated firing in an environment, such as seen in pyramidal cell place fields, they do exhibit significant spatial modulation (McNaughton et al., 1983a). Strong monosynaptic coupling between pyramidal neurons and nearby interneurons in the CA1 stratum pyramidale has been strongly implicated on the basis of significant, short-latency peaks in cross-correlogram plots (Csicsvari et al., 1998). Furthermore, interneurons receiving a putative monosynaptic connection from a simultaneously recorded pyramidal cell appear to inherit the spatial modulation of the latter (Marshall et al., 2002). Buzsaki and colleagues hypothesize that interneurons may also adopt the firing phase dynamics of their afferent place cells, which show a phase shift relative to the hippocampal theta rhythm as a rat passes through the place field (“phase precession”). This study confirms and extends the previous reports by showing that interneurons in the dorsal and middle hippocampus with putative monosynaptic connections with place cells recorded on the same tetrode share other properties with their pyramidal cell afferents, including the spatial scale of the place field of pyramidal cell, a characteristic of the septotemporal level of the hippocampus from which the cells are recorded, and the rate of phase precession, which is slower in middle regions. Furthermore, variations in pyramidal cell place field scale within each septotemporal level attributable to task variations are similarly associated with variations in interneuron place field scale. The available data strongly suggest that spatial selectivity of CA1 stratum pyramidale interneurons is inherited from a small cluster of local pyramidal cells and is not a consequence of spatially selective synaptic input from CA3 or other sources.
Synaptotagmin-2 Is Essential for Survival and Contributes to Ca2+Triggering of Neurotransmitter Release in Central and Neuromuscular Synapses
Authors: Pang Zhiping P. , Melicoff Ernestina , Padgett Daniel , Liu Yun , Teich Andrew F. , Dickey Burton F. , Lin Weichun , Adachi Roberto , Südhof Thomas C.
Published: December 2006

Biochemical and genetic data suggest that synaptotagmin-2 functions as a Ca2+sensor for fast neurotransmitter release in caudal brain regions, but animals and/or synapses lacking synaptotagmin-2 have not been examined. We have now generated mice in which the 5′ end of the synaptotagmin-2 gene was replaced by lacZ. Using β-galactosidase as a marker, we show that, consistent with previous studies, synaptotagmin-2 is widely expressed in spinal cord, brainstem, and cerebellum, but is additionally present in selected forebrain neurons, including most striatal neurons and some hypothalamic, cortical, and hippocampal neurons. Synaptotagmin-2-deficient mice were indistinguishable from wild-type littermates at birth, but subsequently developed severe motor dysfunction, and perished at ∼3 weeks of age. Electrophysiological studies in cultured striatal neurons revealed that the synaptotagmin-2 deletion slowed the kinetics of evoked neurotransmitter release without altering the total amount of release. In contrast, synaptotagmin-2-deficient neuromuscular junctions (NMJs) suffered from a large reduction in evoked release and changes in short-term synaptic plasticity. Furthermore, in mutant NMJs, the frequency of spontaneous miniature release events was increased both at rest and during stimulus trains. Viewed together, our results demonstrate that the synaptotagmin-2 deficiency causes a lethal impairment in synaptic transmission in selected synapses. This impairment, however, is less severe than that produced in forebrain neurons by deletion of synaptotagmin-1, presumably because at least in NMJs, synaptotagmin-1 is coexpressed with synaptotagmin-2, and both together mediate fast Ca2+-triggered release. Thus, synaptotagmin-2 is an essential synaptotagmin isoform that functions in concert with other synaptotagmins in the Ca2+triggering of neurotransmitter release.