bluuebunny/crossref_metadata_2025 huggingface dataset:
The kinematic viscosity of biodiesel and its blends with diesel fuel
Authors: Tat Mustafa E. , Van Gerpen Jon H.
Published: June 2007

As the use of biodiesel becomes more wide‐spread, engine manufacturers have expressed concern about biodiesel’s higher viscosity. In particular, they are concerned that biodiesel may exhibit different viscosity‐temperature characteristics that could result in higher fuel injection pressures at low engine operating temperatures. This study presents data for the kinematic viscosity of biodiesel and its blends with No. 1 and No. 2 diesel fuels at 75, 50, and 20% biodiesel, from close to their melting point to 100°C. The results indicate that while their viscosity is higher, biodiesel and its blends demonstrate temperature‐dependent behavior similar to that of No. 1 and No. 2 diesel fuels. Equations of the same general form are shown to correlate viscosity data for both biodiesel and diesel fuel, and for their blends. A blending equation is presented that allows the kinematic viscosity to be calculated as a function of the biodiesel fraction.
Human SFMBT is a transcriptional repressor protein that selectively binds the N‐terminal tail of histone H3
Authors: Wu Shumin , Trievel Raymond C. , Rice Judd C.
Published: June 2007

Human SFMBT (hSFMBT) is postulated to be a Polycomb (PcG) protein. Similar to other PcG proteins, we found that hSFMBT displays robust transcriptional repressor activity. In addition, hSFMBT localized to the nucleus where it strongly associates with chromatin by directly and selectively binding the N‐terminal tail of histone H3. Importantly, we discovered that the four tandem MBT repeats of hSFMBT were sufficient for nuclear matrix‐association, N‐terminal tail H3 binding, and required for transcriptional repression. These findings indicate that the tandem MBT repeats form a functional structure required for biological activity of hSFMBT and predict similar properties for other MBT domain‐containing proteins.
Resistin down‐regulates insulin receptor expression, and modulates cell viability in rodent pancreatic beta‐cells
Authors: Brown James E.P. , Onyango David J. , Dunmore Simon J.
Published: June 2007

The adipokine resistin is known to induce insulin resistance in rodent tissues. Increases in adipose tissue mass are known to have a negative effect on pancreatic beta‐cell function, although the mechanisms are poorly understood. This study investigated the effects of resistin on insulin secretion, insulin receptor expression and cell viability in pancreatic beta‐cells. BTC‐6 or BRIN‐BD11 cells were treated for 24 h with resistin, and insulin receptor expression, insulin secretion and cell viability were measured. Incubation with 40 ng/ml resistin caused significant decreases in insulin receptor mRNA and protein expression, but did not affect insulin secretion. At low concentrations, resistin caused significant increases in cell viability. These data implicate resistin as a factor that may regulate beta‐cell function/viability, and suggests a potential mechanism by which increased adiposity causes beta‐cell dysfunction.
Effect of rising atmospheric carbon dioxide on the marine nitrogen fixer Trichodesmium
Authors: Barcelos e Ramos J. , Biswas H. , Schulz K. G. , LaRoche J. , Riebesell U.
Published: June 2007

Diazotrophic (N2‐fixing) cyanobacteria provide the biological source of new nitrogen for large parts of the ocean. However, little is known about their sensitivity to global change. Here we show that the single most important nitrogen fixer in today's ocean, Trichodesmium, is strongly affected by changes in CO2 concentrations. Cell division rate doubled with rising CO2 (glacial to projected year 2100 levels) prompting lower carbon, nitrogen and phosphorus cellular contents, and reduced cell dimensions. N2 fixation rates per unit of phosphorus utilization as well as C:P and N:P ratios more than doubled at high CO2, with no change in C:N ratios. This could enhance the productivity of N‐limited oligotrophic oceans, drive some of these areas into P limitation, and increase biological carbon sequestration in the ocean. The observed CO2 sensitivity of Trichodesmium could thereby provide a strong negative feedback to atmospheric CO2 increase.
Nonlinear ion‐acoustic waves supported by an ion beam
Authors: Gomberoff L.
Published: June 2007

It is shown that in a plasma composed by electrons, a proton core, and a proton beam propagating along an external magnetic field, finite amplitude left‐hand polarized waves propagating backward relative to the beam direction can trigger nonlinear ion‐acoustic waves supported by the beam. A detailed study of such instabilities is carried out. The instability bounds are such that if there are large amplitude left‐hand polarized waves propagating toward the Sun, nonlinear ion‐acoustic waves supported by the beam should exist in high‐speed solar wind streams.
Reconstruction of internal gravity wave and turbulence parameters in the stratosphere using GOMOS scintillation measurements
Authors: Sofieva V. F. , Gurvich A. S. , Dalaudier F. , Kan V.
Published: June 2007

Exploitation of stellar scintillation allows studying air density irregularities in the stratosphere. In this paper, we develop a methodology for reconstruction of internal gravity wave (IGW) and turbulence parameters using scintillation measurements by the Global Ozone Monitoring by Occultation of Star (GOMOS) fast photometers on board the Envisat satellite. The forward model is based on a two‐component spectral model of air density irregularities: the first component corresponds to the gravity wave spectrum, while the second one describes locally isotropic turbulence resulting from internal gravity wave breaking. The retrieval of parameters of IGW and turbulence spectra is based on the maximum likelihood method. The developed algorithm is tested on simulated and real data, and its accuracy is assessed. It is shown that the measured scintillation spectra are in good agreement with the proposed model and that structure characteristics and inner and outer scales of the anisotropic component can be reconstructed from scintillation spectra. The developed method can provide information about global distribution of parameters of IGW and turbulence spectra in the stratosphere at altitudes from 25 to 50 km.
The influence of atmospheric zonal wave three on Antarctic sea ice variability
Authors: Raphael M. N.
Published: June 2007

The study examines the relationship between atmospheric zonal wave three and Antarctic sea ice variability using an index of zonal wave three and sea ice concentration. The net sensible heat flux and the surface air temperature are used to explain the apparent atmosphere‐sea ice interaction. The results show that zonal wave three forces an alternating pattern of equatorward (colder) and poleward (warmer) flow which influences the temperature difference between the atmosphere and the ocean. The net sensible heat flux is positive, ocean heat loss is greater, and sea ice growth and expansion is greater in regions of colder air. The reverse is true in regions of warmer air. This influence of zonal wave three on sea ice concentration appears greatest in the southern fall and early winter. It is most clearly seen in the Ross and Weddell Seas outflows and off the Amery iceshelf.
Impact of disturbed desert soils on duration of mountain snow cover
Authors: Painter Thomas H. , Barrett Andrew P. , Landry Christopher C. , Neff Jason C. , Cassidy Maureen P. , Lawrence Corey R. , McBride Kathleen E. , Farmer G. Lang
Published: June 2007

Snow cover duration in a seasonally snow covered mountain range (San Juan Mountains, USA) was found to be shortened by 18 to 35 days during ablation through surface shortwave radiative forcing by deposition of disturbed desert dust. Frequency of dust deposition and radiative forcing doubled when the Colorado Plateau, the dust source region, experienced intense drought (8 events and 39–59 Watts per square meter in 2006) versus a year with near normal precipitation (4 events and 17–34 Watts per square meter in 2005). It is likely that the current duration of snow cover and surface radiation budget represent a dramatic change from those before the widespread soil disturbance of the western US in the late 1800s that resulted in enhanced dust emission. Moreover, the projected increases in drought intensity and frequency and associated increases in dust emission from the desert southwest US may further reduce snow cover duration.
Evidence for carrier-induced ferromagnetic ordering in Zn1−xMnxO thin films: Anomalous Hall effect
Authors: Shim Wooyoung , Lee Kyoung-il , Lee Wooyoung , Jeon Kyung Ah , Lee Sang Yeol , Jung Myung Hwa
Published: June 2007

The intrinsic origin of the ferromagnetic ordering in Zn1−xMnxO thin films grown by pulsed-laser deposition was investigated. The ferromagnetic behaviors for a Zn1−xMnxO (x=0.26) film grown at 700 °C under oxygen pressures of 10−1 Torr were observed at 4 and 300 K. The anomalous Hall effect (AHE) was found at temperatures of up to 210 K for the Zn0.74Mn0.26O thin film. The anomalous Hall coefficients (RA) were determined to be approximately proportional to the square of resistivity in the low field region, indicating the side-jump process for the AHE. Our results provide direct experimental evidence that a carrier-mediated mechanism is responsible for the ferromagnetic ordering in Zn1−xMnxO thin films grown by pulsed-laser deposition.
Simple system for locating ground loops
Authors: Bellan P. M.
Published: June 2007

A simple low-cost system for rapid identification of the cables causing ground loops in complex instrumentation configurations is described. The system consists of an exciter module that generates a 100kHz ground loop current and a detector module that determines which cable conducts this test current. Both the exciter and detector are magnetically coupled to the ground circuit so there is no physical contact to the instrumentation system under test.
Explosion of electron bubbles attached to quantized vortices in liquid He4
Authors: Pi Martí , Mayol Ricardo , Hernando Alberto , Barranco Manuel , Ancilotto Francesco
Published: June 2007

Electron bubbles in superfluid He4 have been recently observed in low-temperature cavitation measurements under experimental conditions where quantized vortices are also present in the liquid, and which might be attached to the bubbles. We have calculated, within density functional theory, the structure and energetics of electron bubbles pinned to linear vortices in liquid He4 at low temperature, and the pressure at which such structures become mechanically unstable. Our results are in semiquantitative agreement with the experiments. We discuss dynamical effects not included in the theoretical model used in the present calculations, and which could explain some discrepancies between our results and the experimental data.
Instrumented tracer for Lagrangian measurements in Rayleigh-Bénard convection
Authors: Shew Woodrow L. , Gasteuil Yoann , Gibert Mathieu , Metz Pascal , Pinton Jean-François
Published: June 2007

We have developed novel instrumentation for making Lagrangian measurements of temperature in diverse fluid flows. A small neutrally buoyant capsule is equipped with on-board electronics which measures temperature and transmits the data via a wireless radio frequency link to a desktop computer. The device has 80dB dynamic range, resolving millikelvin changes in temperature with up to 100ms sampling time. The capabilities of these “smart particles” are demonstrated in turbulent thermal convection in water. We measure temperature variations as the particle is advected by the convective motion and analyze its statistics. Additional use of cameras allow us to track the particle position and to report here the first direct measurement of Lagrangian heat flux transfer in Rayleigh-Bénard convection. The device shows promise for opening new research in a broad variety of fluid systems.
Wallplug efficiency of quantum cascade lasers: Critical parameters and fundamental limits
Authors: Faist Jérôme
Published: June 2007

Fundamental limits in the wallplug efficiency of quantum cascade lasers are derived in a rate equation model that uses global effective parameters. Free carrier absorption and thermal population of the lower state force a strong downward trend of this efficiency with increasing wavelength, that agrees well with experimental data taken from literature.
Structural analysis of dilute-nitride zinc blende InxGa1−xNyAs1−y cluster by a semiempirical quantum chemistry study
Authors: Han T.-T. , Fu Y. , Wang S.-M. , Larsson A.
Published: June 2007

We have studied the total energy of a series of dilute-nitride zinc blende InxGa1−xNyAs1−y cluster configurations using a semiempirical quantum chemistry method. It was found that In–N bonding is favorable from an energy point of view when the N atom is substitutional (replacing an As atom at the regular zinc blende lattice site) and the In mole fraction is smaller than 25%. In–N bonding is always favorable when the N atom is interstitial. Furthermore, an analysis of the incorporation of N–N pairs showed that substitutional incorporation is favored over interstitial. In addition, the dissociation of a N–N pair was found to depend on the local environment, being either In rich or In-free, along the dissociation trajectory when the average In mole fraction is high. The theoretical results are in agreement with experimental results.
High-frequency responses of granular CoFeHfO and amorphous CoZrTa magnetic materials
Authors: Li Liangliang , Lee Dok Won , Mao Ming , Schneider Thomas , Bubber Randhir , Hwang Kyu-Pyung , Min Yongki , Wang Shan X.
Published: June 2007

High-resistivity soft magnetic materials are receiving much attention as they have relatively low core loss at high frequencies. We developed magnetically soft granular CoFeHfO material by pulsed-dc reactive magnetron sputtering and compared its electrical and magnetic properties, especially permeability spectra, with those of amorphous CoZrTa material. We also investigated the permeability spectra of patterned CoFeHfO films with different thicknesses and observed their magnetic domain structures by Kerr imaging microscopy. The granular CoFeHfO material has a better high-frequency response than the amorphous CoZrTa at thicknesses beyond ∼0.5μm, if the ratio of the real/imaginary parts of the permeability is the principal figure of merit, and is an excellent candidate for high-frequency applications such as integrated magnetic inductors.
Effects of laser sources on the reverse-bias leakages of laser lift-off GaN-based light-emitting diodes
Authors: Wu Yewchung Sermon , Cheng Ji-Hao , Peng Wei Chih , Ouyang Hao
Published: June 2007

The KrF pulsed excimer laser (248nm) and the frequency-tripled neodymium doped yttrium aluminum garnet laser (355nm) have been used to separate GaN thin films from sapphire substrates and transfer to bond other substrate. However, these processes would increase the dislocation density, resulting in an increase of the leakage current. In this study, the effects of these two laser sources on the reverse-bias leakages of InGaN–GaN light-emitting diodes were studied.
Strain and friction induced by van der Waals interaction in individual single walled carbon nanotubes
Authors: Son Hyungbin , Samsonidze Georgii G. , Kong Jing , Zhang Yingying , Duan Xiaojie , Zhang Jin , Liu Zhongfan , Dresselhaus Mildred S.
Published: June 2007

Axial strain is introduced into individual single wall carbon nanotubes (SWCNTs) suspended from a trench-containing Si∕SiO2 substrate by employing the van der Waals interaction between the SWCNT and the substrate. Resonance Raman spectroscopy is used to characterize the strain, and up to 3% axial strain is observed. It is also found that a significant friction between the SWCNT and the substrate, on the order of 10pN∕nm, governs the localization and propagation of the strain in the SWCNTs sitting on the substrate. This method can be applied to introduce strain into materials sitting on a substrate, such as a graphene sheet.
Magnitude of the intrinsic electrocaloric effect in ferroelectric perovskite thin films at high electric fields
Authors: Akcay G. , Alpay S. P. , Mantese J. V. , Rossetti G. A.
Published: June 2007

Monodomain contributions to the electrocaloric effect in mechanically free (bulk) and laterally clamped (thin film) BaTiO3 are computed using a thermodynamic analysis. The authors show that the intrinsic electrocaloric coefficient at electric fields sufficient to destroy the discontinuous ferroelectric phase transition results in an adiabatic temperature change of 8K that agrees closely with the giant value of 12K recently observed experimentally for lead zirconate titanate thin films [A. S. Mischenko et al., Science 311, 1270 (2006)]. Perfect lateral clamping transforms the discontinuous transition into a continuous transition, which decreases the magnitude of the electrocaloric effect by 20% but reduces its sensitivity to temperature.
High mobility vanadyl-phthalocyanine polycrystalline films for organic field-effect transistors
Authors: Wang Haibo , Song De , Yang Junliang , Yu Bo , Geng Yanhou , Yan Donghang
Published: June 2007

The organic films of vanadyl-phthalocyanine (VOPc) compounds showed weak epitaxy growth (WEG) behavior on thin ordered para-sexiphenyl (p-6P) layer with high substrate temperature. The WEG of VOPc molecules standing up on the p-6P layer leaded to high in-plane orientation and their layer-by-layer growth behavior. In consequence, high quality VOPc films were obtained, which were consisted of lamellar crystals. Organic field-effect transistors with VOPc∕p-6P films as active layers realized high mobility of above 1cm2∕Vs. This result indicated that nonplanar compounds can obtain a device performance better than planar compounds, therefore, it may provide a rule to find disklike organic semiconductor materials.
Encapsulation of pentacene/C60 organic solar cells with Al2O3 deposited by atomic layer deposition
Authors: Potscavage W. J. , Yoo S. , Domercq B. , Kippelen B.
Published: June 2007

Organic solar cells based on pentacene/C60 heterojunctions were encapsulated using a 200-nm-thick film of Al2O3 deposited by atomic layer deposition (ALD). Encapsulated devices maintained power conversion efficiency after exposure to ambient atmosphere for over 6000h, while devices with no encapsulation degraded rapidly after only 10h of air exposure. In addition, thermal annealing associated with the ALD deposition is shown to improve the open-circuit voltage and power conversion efficiency of the solar cells.
High-energy conformer of formic acid in solid neon: Giant difference between the proton tunneling rates of cis monomer and trans-cis dimer
Authors: Marushkevich Kseniya , Khriachtchev Leonid , Räsänen Markku
Published: June 2007

We study the conformational reorganization of formic acid (FA) in solid neon and report the higher-energy cis-FA monomer and one form of the trans-cis FA dimers. They were prepared by selective vibrational excitation of the trans-FA monomer and trans-trans dimer. The proton tunneling decay of cis-FA monomer is surprisingly very fast in solid neon, two orders of magnitude faster than in solid argon. It was also found that the stability of the trans-cis dimer against proton tunneling is enormously enhanced in solid neon compared to the monomer (by a factor of ∼300). These results are discussed in terms of matrix solvation and hydrogen bonding.
Ammonia/ammonium dissociation coefficient in seawater: A significant numerical correction
Authors: Bell Thomas G. , Johnson Martin T. , Jickells Timothy D. , Liss Peter S.
Published: June 2007

Environmental context. Quantifying ammonia concentrations in natural waters is important for our understanding of environmental processes that relate, in particular, to aquaculture toxicity and to the transfer of gaseous ammonia into the atmosphere where it plays a role in new particle formation and climate regulation. The proportion of ammonia present in natural waters is determined in part by variations in temperature and salinity. This work identifies that a previous equation for predicting ammonia concentrations over natural temperature and salinity ranges is incorrect and suggests alternative, more appropriate equations. A more accurate estimation of environmental ammonia concentrations is essential if improved estimates are to be made of the flux of ammonia into the atmosphere and the level of ammonia toxicity within aquacultures.
Abstract. The equilibrium between ammonia (NH3) and ammonium (NH4+) in aqueous solution is a function of temperature, pH and the ionic strength of the solution. Here we reveal a 30-year-old error in published work on the thermodynamics of ammonium dissociation in seawater, which has propagated throughout the literature. The work in question[1] [K. H. Khoo, C. H. Culberson, R. G. Bates, J. Solution Chem. 1977, 6, 281] presents an incorrect expression for the variation of the acid dissociation coefficient (Ka) of ammonium with temperature and ionic strength. We detail the error and reveal that it can lead to as much as a 500% overestimation in calculated NH3 concentration under environmental conditions. This finding is highly relevant, particularly for studies of ammonia toxicity and air–sea ammonia exchange. In addition, we recommend two expressions that better reproduce previous experimental work: (i) taken from the work of Johansson and Wedborg,[2] and (ii) our own derivation using the dataset of Khoo et al.[1]
Precursors to Particles (P2P) at Cape Grim 2006: campaign overview
Authors: Cainey Jill M. , Keywood Melita , Grose Michael R. , Krummel Paul , Galbally Ian E. , Johnston Paul , Gillett Rob W. , Meyer Mick , Fraser Paul , Steele Paul , Harvey Mike , Kreher Karin , Stein Torsten , Ibrahim Ossama , Ristovski Zoran D. , Johnson Graham , Fletcher Cathie A. , Bigg E. Keith , Gras John L.
Published: June 2007

Environmental context. Understanding the role of clouds in assessing the impact of climate change is a challenging issue. It is thought that plankton and seaweed contribute to the formation of clouds by emitting gases that lead to the particle production necessary for cloud formation. Macroalgae (kelp) at Mace Head, Ireland, produce large quantities of iodine when exposed to sunlight at low tide and this iodine results in the rapid production of particles. Cape Grim, Tasmania, also has large colonies of kelp and the role of Bull Kelp (Durvillaea potatorum) in particle production was assessed.
Abstract. Iodine emissions from coastal macroalgae have been found to be important initiators for nucleation events at Mace Head, Ireland. The source of this iodine is the large beds of the brown kelp Laminaria digitata, which are significantly exposed at low tide.
On the coast around Cape Grim, Tasmania, there are beds of the brown kelp Durvillaea potatrum. The Precursors to Particles 2006 (P2P 2006) campaign at the Cape Grim Baseline Air Pollution Station in late summer (February) 2006 focused on the role of this local kelp in providing precursor gases to particle formation.
Durvillaea potatorum does not produce iodated precursor gases at the levels observed at Mace Head. IO was measured at 0.5 ± 0.3 ppt, while OIO was below detection limits (9 ppt). The dominant atmospheric iodated species was methyl iodide and the average concentration measured at the Cape Grim Station was 1.5 ± 0.3 pptv in baseline conditions, but showed significant variation in discrete samples collected immediately above the ocean surface.
Nucleation events were not detected at the Cape Grim Station, except for one period where the plume of a local bushfire interacted with air of marine origin. The passage of four fronts did not result in nucleation bursts and measurements on the beach 94 m below the Cape Grim Station suggested that Durvillaea potatorum was only a weak source of new particles.
Recursive subhomogeneous algebras
Authors: Phillips N.
Published: June 2007

We introduce and characterize a particularly tractable class of unital type 1 C*-algebras with bounded dimension of irreducible representations. Algebras in this class are called recursive subhomogeneous algebras, and they have an inductive description (through iterated pullbacks) which allows one to carry over from algebras of the form

C
(
X
,

M
n

)

C (X, M_n)

many of the constructions relevant in the study of the stable rank and K-theory of simple direct limits of homogeneous C*-algebras. Our characterization implies, in particular, that if

A
A

is a separable C*-algebra whose irreducible representations all have dimension at most

N
>
∞
,

N > \infty ,

and if for each

n
n

the space of

n
n

-dimensional irreducible representations has finite covering dimension, then

A
A

is a recursive subhomogeneous algebra. We demonstrate the good properties of this class by proving subprojection and cancellation theorems in it. Consequences for simple direct limits of recursive subhomogeneous algebras, with applications to the transformation group C*-algebras of minimal homeomorphisms, will be given in separate papers.
Mixed multiplicities of ideals versus mixed volumes of polytopes
Authors: Trung Ngo , Verma Jugal
Published: June 2007

The main results of this paper interpret mixed volumes of lattice polytopes as mixed multiplicities of ideals and mixed multiplicities of ideals as Samuel’s multiplicities. In particular, we can give a purely algebraic proof of Bernstein’s theorem which asserts that the number of common zeros of a system of Laurent polynomial equations in the torus is bounded above by the mixed volume of their Newton polytopes.
Equivalence of domains arising from duality of orbits on flag manifolds III
Authors: Matsuki Toshihiko
Published: June 2007

In Gindikin and Matsuki 2003, we defined a

G

R

G_{\mathbb {R}}

-

K

C

K_{\mathbb C}

invariant subset

C
(
S
)

C(S)

of

G

C

G_{\mathbb {C}}

for each

K

C

K_{\mathbb C}

-orbit

S
S

on every flag manifold

G

C

/

P

G_{\mathbb C}/P

and conjectured that the connected component

C
(
S

)
0

C(S)_0

of the identity would be equal to the Akhiezer-Gindikin domain

D
D

if

S
S

is of nonholomorphic type. This conjecture was proved for closed

S
S

in Wolf and Zierau 2000 and 2003, Fels and Huckleberry 2005, and Matsuki 2006 and for open

S
S

in Matsuki 2006. It was proved for the other orbits in Matsuki 2006, when

G

R

G_{\mathbb {R}}

is of non-Hermitian type. In this paper, we prove the conjecture for an arbitrary non-closed

K

C

K_{\mathbb C}

-orbit when

G

R

G_{\mathbb {R}}

is of Hermitian type. Thus the conjecture is completely solved affirmatively.
Compatible valuations and generalized Milnor 𝐾-theory
Authors: Efrat Ido
Published: June 2007

Given a field

F
F

and a subgroup

S
S

of

F

×

F^{\times }

there is a minimal group

S
≤

H

S

≤

F

×

S\leq H_{S}\leq F^{\times }

for which there exists an

S
S

-compatible valuation whose units are contained in

H

S

H_{S}

. Assuming that

S
S

has finite index in

F

×

F^{\times }

and contains

(

F

×

)

p

(F^{\times })^{p}

for

p
p

prime, we describe

H

S

H_{S}

in computable

K
K

-theoretic terms.
Morse decompositions of nonautonomous dynamical systems
Authors: Rasmussen Martin
Published: June 2007

The global asymptotic behavior of dynamical systems on compact metric spaces can be described via Morse decompositions. Their components, the so-called Morse sets, are obtained as intersections of attractors and repellers of the system. In this paper, new notions of attractor and repeller for nonautonomous dynamical systems are introduced which are designed to establish nonautonomous generalizations of the Morse decomposition. The dynamical properties of these decompositions are discussed, and nonautonomous Lyapunov functions which are constant on the Morse sets are constructed explicitly. Moreover, Morse decompositions of one-dimensional and linear systems are studied.
Concentration Gradient Along the Scala Tympani After Local Application of Gentamicin to the Round Window Membrane
Authors: Plontke Stefan K. , Mynatt Robert , Gill Ruth M. , Borgmann Stefan , Salt Alec N.
Published: June 2007

Objectives: The distribution of gentamicin along the fluid spaces of the cochlea after local applications has never previously been demonstrated. Computer simulations have predicted that significant basal‐apical concentration gradients might be expected, and histologic studies indicate that hair cell damage is greater at the base than at the apex after local gentamicin application. In the present study, gradients of gentamicin along the cochlea were measured.

Methods: A recently developed method of sampling perilymph from the cochlear apex of guinea pigs was used in which the samples represent fluid originating from different regions along the scala tympani. Gentamicin concentration was determined in sequential apical samples that were taken after up to 3 hours of local application to the round window niche.

Results: Substantial gradients of gentamicin along the length of the scala tympani were demonstrated and quantified, averaging more than 4,000 times greater concentration at the base compared with the apex at the time of sampling. Peak concentrations and gradients for gentamicin varied considerably between animals, likely resulting from variations in round window membrane permeability and rates of perilymph flow.

Conclusions: The large gradients for gentamicin demonstrated here in guinea pigs account for how it is possible to suppress vestibular function in some patients with a local application of gentamicin without damaging auditory function. Variations in round window membrane permeability and in perilymph flow could account for why hearing losses are observed in some patients.
Measurement of Angle and Length of the Eustachian Tube on Computed Tomography Using the Multiplanar Reconstruction Technique
Authors: Takasaki Kenji , Takahashi Haruo , Miyamoto Ikue , Yoshida Haruo , Yamamoto‐Fukuda Tomomi , Enatsu Kaori , Kumagami Hidetaka
Published: June 2007

Objective: To compare the anatomic features of the eustachian tube (ET) between children with and without otitis media with effusion (OME) and with adults.

Methods: The angle and length of the ET in children with OME (54 ears, OME children) and without OME (50 ears, normal children), as well as those of normal adults (90 ears), were measured on computed tomography using the multiplanar reconstruction technique.

Results: The angles of ET in the OME children group, the normal children group, and the normal adult group were 20.4 ± 3.5° and 21.2 ± 4.8°, 19.9 ± 3.4° and 20.0 ± 3.6°, and 27.3 ± 2.7° and 27.3 ± 2.8° on the right and the left sides, respectively. There was no significant difference between the right and the left side in any group (P = .541, P = .952, P = .978). The lengths of ET in the OME children group, the normal children group, and the normal adult group were 37.2 ± 3.0 mm (mean ± SD) and 37.6 ± 3.2 mm, 37.5 ± 3.3 mm and 38.0 ± 3.2 mm, and 42.5 ± 2.8 mm and 42.9 ± 2.9 mm on the right and the left sides, respectively. There was no significant difference between the right and left sides in any group (P = .670, P = .597, and P = .545). Both the angles and lengths were significantly greater in the normal adult group than in either the OME children group or the normal children group (one‐way analysis of variance and Fisher's protected least significant difference tests, P < .05), but there was no significant difference in either the angle or length of the ET between the OME and normal children groups (P > .05). In the OME and normal children groups, the angle was observed to constantly increase with age, and the values were found to be within the range of the adult size in all the patients older than 7.5 years and 7.7 years in the OME children group and the normal children group, respectively. As well as the angle, the lengths were observed to constantly increase with age, but the increase appeared to be greater at a younger age (until approximately 3 to 4 years) than at an older age, and the values were found to be within the range of the adult size in all the patients older than 6.8 years and 7.7 years in the OME children group and the normal children group, respectively.

Conclusion: The angle and length of the ET are more horizontal and shorter in infants than in adults. However, there is no statistical difference between the angle and length of the ET in infants with and without OME. These results lead us to believe that a short and horizontal ET may not be a main etiologic factor related to high susceptibility to OME in infants and children.
Vestibular Rehabilitation Exercises in Acute Vertigo
Authors: Venosa Alessandra R. , Bittar Roseli S.
Published: June 2007

Objectives/Hypothesis: To evaluate the effect of vestibular rehabilitation exercises in the early stages of peripheral vestibular disorders.

Study Design: Prospective, randomized trial. Patients were blinded to assignment groups.

Methods: The study group (45 patients) performed exercises for adaptation of the vestibulo‐ocular reflex; the control group (42 patients) performed placebo exercises. Both groups were instructed to use dimenhydrinate (up to 150 mg/d) if symptomatic, irrespective of exercises. Patients were evaluated by visual analogue scale, physical examination, and need to use the medication. All patients were adults and symptomatic for less than 5 days.

Results: The study and control groups were comparable in terms of demographics data and duration and intensity of symptoms. Study group patients recovered faster than controls and used less medication. By 10 to 14 days after the intervention, 43% of study group and 5% of control group patients had no significant symptoms (P < .001), and 67% of study group and 3% of control group patients needed no medication (P < .001). Although both groups had no significant symptoms by the end of the follow‐up period (21 days), 14% of the study group patients were still using medication, compared with 83% of the placebo group patients (P < .001).

Conclusions: Vestibular exercises are effective in reducing the duration of symptoms and the need of medication of patients in the early stages of peripheral vestibular disorders.
Omeprazole for Gastroesophageal Reflux Disease in the First 2 Years of Life: A Dose‐finding Study With Dual‐channel pH Monitoring
Authors: Bishop Jonathan , Furman Mark , Thomson Mike
Published: June 2007

Background and Aim:

Gastroesophageal reflux occurs in the majority of infants, with severity ranging from asymptomatic to severe esophagitis and failure to thrive. Omeprazole is recognized as a safe and effective treatment of gastroesophageal reflux in older children, at an initial dosage of 0.7 mg · kg−1 · day−1. To our knowledge, no dose‐finding studies have been carried out in children under 2 years of age. The aim of the present study was to prospectively determine the dosage of omeprazole required to treat symptomatic gastroesophageal reflux in children younger than 2 years.

Patients and Methods:

Children under 2 years with clinical suspicion of gastroesophageal reflux underwent 24‐hour dual‐channel intraesophageal/gastric pH monitoring. A reflux index above 10% in children under 1 year and above 6% in children older than 1 year was deemed significant. Treatment with omeprazole at an initial dosage of 0.7 mg · kg−1 · day−1 (in 2 divided doses) was followed by dual‐channel pH study after 14 days. The dosage was increased in increments of 0.7 mg · kg−1 · day−1, and pH studies were repeated until the gastroesophageal reflux was controlled.

Results:

Ten children (5 male, 5 female), mean age 7.75 months (range, 1.25–20 months), were investigated. The initial median reflux index was 18.5% (range, 6.5%–56.3%). Follow‐up median reflux index was improved at 1.6% (0.1%–8.1%) (P < 0.05). The median dosage required was 1.05 mg · kg−1 · day−1. Four children required 1.4 mg · kg−1 · day−1, and 1 required 2.8 mg · kg−1 · day−1. Corrected reflux index improved from 34.8% (16.8%–90.8%) to 20.1% (0.4%–100%) but did not achieve statistical significance. There were no serious complications or side effects.

Conclusions:

Omeprazole is an effective treatment for gastroesophageal reflux in children younger than 2 years. The majority respond to a dosage of 0.7 mg · kg−1 · day−1, but increased dosages up to 2.8 mg · kg−1 · day−1 may be required.
Robots at the heart of Schubert packaging machinery lead to great flexibility
Authors: Connolly Christine
Published: June 2007

Purpose

To study the advantages of a modular approach to packaging‐machine design.

Design/methodology/approach

Introduces the modular approach of this German company, with particular emphasis on its packaging robots and vision system. Uses a selection of food and pharmaceutical applications to illustrate the flexibility, capability and throughput of these compact packaging lines. Briefly, mentions other innovative features of the company's product range.

Findings

The company has reduced its top‐loading range of packaging machinery to just seven modules, of which a two‐ and a four‐axis robot greatly assist operational flexibility. A patented counterflow conveyor system unites products and packing boxes in a space‐saving layout. The de‐central control system reduces installation costs and assists trouble‐shooting.

Originality/value

Illustrates the power of robot technology in achieving a new approach to a particular type of automated machinery.
A search and rescue robot with tele‐operated tether docking system
Authors: Marques Carlos , Cristóvão João , Alvito Paulo , Lima Pedro , Frazão João , Ribeiro Isabel , Ventura Rodrigo
Published: June 2007

Purpose

To describe a robot designed and built to operate in outdoor environments hostile to the human presence, such as debris resulting from the collapse of built structures, and targeted to the tele‐operated detection of potential survivors using a set of specific sensors whose information is transmitted to a remote human operator.

Design/methodology/approach

RAPOSA's mechanical structure is composed of a main body and a front body, whose locomotion is supported on tracked wheels, allowing motion even when the robot is upside down. The front body has variable tilting capabilities, providing means to overcome edges higher than the robot main body (e.g. when climbing a stair) and is also useful to grab the lower ground when only the main body has ground contact. This front body has one thermal camera and two webcameras installed. Additional sensors include gas, temperature and humidity sensors, web cams, light diodes, microphone and loudspeaker. The robot uses wireless communications, with an option for tethered operation.

Findings

The robot was tested in several scenarios of the Fire Fighters school. In this particular exercise, the robot reduced the inspection time down to 25 percent of the time that specialized firefighters teams would take to finish the exercise. This was due to the fact that the firefighters need to stabilize the environment in order to reduce live threats. In this case, as in many other similar situations, not only the robot provides a faster inspection method, but also a much safer one.

Originality/value

The tether carries both power and communications, with an access point on its end. Docking and undocking the robot to the tether is accomplished remotely by the operator with the help of a camera located inside the robot, and represents the most innovative feature of RAPOSA.
Integration of marketing domain and R&D domain in NPD design process
Authors: Kang Namwoo , Kim Junyoung , Park Yongtae
Published: June 2007

Purpose

To solve the trade‐offs between marketing and R&D domains and to minimize information loss in new product development (NPD), this study proposes an integrated design process as a new solution to the interface system between the two domains.

Design/methodology/approach

House of Quality integrated with multivariate statistical analysis is used for determining important design features. These design features are used as parameters for conjoint analysis and Taguchi method, and then the results of analyses are compared. Sequential application of conjoint analysis and Taguchi method, depending on the differences in utilities and signal to noise ratios, is applied for the integrated design process. An automotive interior design is illustrated for the validation of the integrated design process.

Findings

The integrated design process determines a point of compromise between the optimums of conjoint analysis and Taguchi method. Sequential application of two methods ensures full utilization of both methods and no loss of information.

Research limitations/implications

More illustrations on NPD are needed to verify the proposed process.

Practical implications

The design process suggested in this study can be used for process innovation in six sigma approach and be integrated with value chain intelligently. This study proposes the strategic guideline of the integrated design process for enterprises.

Originality/value

The integrated design process suggests the solution for the trade‐offs between marketing domain that pursues the utility of product and R&D domain that emphasizes robustness of product quality. This integrated design process will give enterprises competitive advantages in NPD.
The complexity of relationship marketing for service customers
Authors: Ward Tony , Dagger Tracey S.
Published: June 2007

Purpose

There are a number of assumptions inherent in relationship marketing, including claims that a relationship should be developed with all customers in all situations. This paper seeks to show that marketers should not automatically use relationship marketing techniques for all products and for all customers.

Design/methodology/approach

This paper reports the results of an empirical survey of 287 consumers for five service products in which consumers were asked to assess the strength of the relationship between themselves and their supplier.

Findings

Relationship strength was found to vary significantly between service products and individual customers, and the impact of duration of the relationship and the frequency of purchase on relationship strength depends greatly on the nature of the service product. It was also demonstrated that some customers want a closer relationship with service providers than other customers, and this aspect significantly affects the strength of relationship perceived by the customer.

Practical implications

This paper clearly shows that the use of relationship marketing techniques for service products needs to be much more thoroughly researched to provide guidance for practitioners and marketing theorists. The complexity of the “relationship” construct in marketing is clearly shown and there is as yet no known set of “rules” that indicate when relationship marketing techniques should, or should not, be used.

Originality/value

The contribution of this paper is to empirically demonstrate that not all customers want to develop relationships with all service suppliers.
The challenge of human interdependence
Authors: Stacey Ralph
Published: June 2007

Purpose

The purpose of this paper is to locate the dominant discourse on organizations and their management in the history of Western thought. Such location highlights the fundamental, taken‐for‐granted assumptions underlying the dominant discourse. The purpose is also to identify an alternative way of thinking about organizations, which derives from different fundamental assumptions.

Design/methodology/approach

The approach adopted in the paper is to review two fundamentally different approaches in Western thought to understanding the nature of the individual human agent, the organization and the relationship between them. One approach derives from the philosophy of Kant and the other from Hegel.

Findings

The exploration of different ways of thinking in this paper leads to a major undermining of the dominant discourse and overturns the most widespread prescriptions for strategic management and the management of change.

Originality/value

In doing so the paper has profound significance for the conceptualization of leadership and values in organizations.
The evolution and future of logistics and supply chain management
Authors: Ballou Ronald H.
Published: June 2007

Purpose

This paper traces the evolution of logistics and supply chain management (SCM) and projects the state of the field in the near term with the attendant challenges for those who must plan and control logistics/supply chain operations.

Design/methodology/approach

Key events that created business logistics are noted, the views of the field leaders are identified and assessed, and research outcomes are compared as a basis for how logistics/SCM is viewed today.

Findings

The scope of the field has broadened bringing new challenges for researchers and managers, but the broader scope was envisioned from its formation. Improvements in information technology and the just‐in‐time philosophy are the principal drivers for realizing the potential of boundary‐spanning channel management.

Research limitations/implications

The conclusions and projections are based on the author's interpretation of the events surrounding logistics and the supply chain as they have occurred over the last 45 years.

Practical implications

Researchers and managers should find the projections of this paper valuable in defining their action agendas for improving logistics/supply chain operations. Principal among the challenges is the need for a boundary‐spanning accounting system, for a mechanism of sharing the benefits of cooperation among supply chain members, for enhanced relationship skills of logistics/supply chain managers, and for improved methods of estimating the revenue contribution potential of the supply chain.

Originality/value

The personal observations of the author lend a unique perspective as to how the logistics/supply chain has developed and what challenges face researchers and managers if the future potential of the field is to be realized.