bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrogen sensors based on Pt‐AlGaN/GaN back‐to‐back Schottky diode
Authors: Wang Xinhua , Wang Xiaoliang , Xiao Hongling , Feng Chun , Wang Xiaoyan , Wang Baozhu , Yang Cuibai , Wang Junxi , Wang Cuimei , Ran Junxue , Hu Guoxin , Li Jinmin 
Published: May 2008

AbstractIn this paper, platinum (Pt) with a thickness of 45 nm was sputtered on the surface of AlGaN/GaN heterostructure to form the Schottky contact and the back‐to‐back Schottky diodes were characterized for H2 sensing at room temperature. Both the forward and reverse current of the devices increased with exposure to H2 gas, which was attributed to Schottky barrier height reduction caused by hydrogen absorption in the catalytic metals. A shift of 0.7 V at 297 K was obtained at a fixed forward current of 0.1 mA after switching from N2 to 40% H2 in N2. The sensor's responses under different concentrations from 2500 ppm H2 to 40% H2 in N2 at 297 K were investigated. Time response of the sensor at a fixed bias of 1 V was given. Finally, the decrease of the Schottky barrier height and the sensitivity of the sensor were calculated. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Device characteristics of back channel‐modified organic thin‐film transistors
Authors: Hoshino S. , Suemori K. , Yoshida M. , Uemura S. , Kodzasa T. , Takada N. , Kamata T. 
Published: May 2008

AbstractInfluence of back‐channel electronic state on device characteristics was investigated for pentacene‐based thin‐film transistors (TFTs), where top surface of the semiconductor layer was covered with an LiF thin film. We observed higher field‐effect hole mobility in the TFTs with the LiF‐covered back channel than in the corresponding uncovered counterparts. In addition, the LiF‐covered TFTs exhibited a decrease in turn‐on voltages and an increase in off‐state current depending on the thickness of the LiF layer and top‐ or bottom‐contact configuration of the source and drain electrodes. We attributed the electronic effect brought about by the LiF coating to a downward band bending in the back channel originating from a rearrangement of the electronic energy‐level alignment at the pentacene/LiF interface. The difference in the device characteristics from those of the uncovered TFTs was successfully explained by such electronic processes in the pentacene layer induced by the downward band bending in the back channel as a pseudo ‐back gate effect and generation of offsetting holes against the surface electronegativity. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polycrystallization phenomena of organic alloy and multilayer structures on naphthyl‐substituted diamine‐based hole transport layer for organic light‐emitting diode
Authors: Mori T. , Iida Y. 
Published: May 2008

AbstractWe demonstrated the polycrystallization process of N,N'‐di(1‐naphthyl)‐N,N'‐diphenyl‐1,1'‐diphenyl‐1,4'‐diamine (NPD) and N,N'‐diphenyl‐N,N'‐bis(3‐methylphenyl)‐1,1'‐diphenyl‐4,4'‐diamine (TPD), which is well known as a hole transport material, and the availability of the organic alloy method fabricated by co‐evaporation method. We fabricated multi‐layer structure of NPD and TPD: especially bilayer as a basic and typical structure. One is TPD layer on NPD layer (T/N specimen) and the other is NPD layer on TPD layer (N/T specimen). The polycrystallization of bilayer structure specimens is suppressed as compared with organic NPD:TPD=1:1 alloy specimen. Especially the T/N specimen is found to be stable in an amorphous region. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of the unintentional incorporation of Al during the molecular beam epitaxial growth of GaInNAs quantum well
Authors: Wu S. D. , Kato M. , Uchiyama M. , Higashi K. , Ishikawa F. , Kondow M. 
Published: May 2008

AbstractWe report the effect of unintentional Al incorporation during the growth of GaInNAs/GaAs quantum well (QW) by molecular beam epitaxy (MBE). The effect of extrinsic Al is investigated by secondary ion mass spectrometry. QW grown directly on AlAs layer shows unintentionally incorporated Al with its concentration as high as 1×1018 cm–3, resulting in degraded PL intensity. In order to prevent the Al incorporation, we grow QW without heating up Al source after leaving the MBE chamber within As atmosphere for a long period. The concentration of the extrinsic Al becomes lower than 2×1016 cm–3, leading to a strong PL intensity. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analysis of minority carrier lifetime for InAlAs/InGaAs high electron mobility transistors by using 1.55‐μm femto‐second pulse laser
Authors: Taguchi Hirohisa , Sano Chihiro , Murakami Hiroaki , Oura Masashi , Iida Tsutomu , Takanashi Yoshifumi 
Published: May 2008

AbstractThe minority carrier lifetime (τ) of High electron mobility transistors (HEMTs) made using the InAlAs/InGaAs material system lattice‐matched to the InP substrate had been obtained from optical response measurements with a 1.55‐μm femto‐second pulse laser where the laser was illuminated onto the backside of a wafer. The drain current of HEMTs associated with the optical pulse was detected using a digitizing oscilloscope, and τ was estimated from the exponential dependence of drain current on time. In our current investigation, we found that τ is dominated by the following modes: (1) the amount of time required for holes to transit across the channel toward the source, and (2) the amount of time required for the holes accumulated in the source region to recombine with two‐dimensional electron gas (2DEG) through the Auger mechanism. Because the sheet concentration (ps) of holes accumulated in source region is low at a low source‐to‐drain voltage (VDS), Auger recombination is not predominant, and τ was only dominated by the hole transit time. At a high VDS, ps became high enough for Auger recombination to occur and dominate τ. Furthermore, we investigated the optical power dependence of τ where the optical power was supplied in a continuous wave (CW) to generate photo‐excited holes in a steady state. The value of τ decreased monotonically as VDS increased and saturated in as little as 6x10–10 s when the optical power was increased. The theoretical investigation was made to understand this saturation phenomenon. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bistability operation of photocurrent due to wave‐function coupling of Wannier‐Stark localization states in a GaAs/AlAs superlattice
Authors: Hasegawa T. , Nakayama M. 
Published: May 2008

AbstractWe have investigated effects of the resonant wave‐function coupling between Wannier‐Stark localization states on photocurrent properties in a GaAs (6.8 nm)/Al0.1Ga0.9As (4.0 nm) superlattice. The resonant coupling, which causes an anticrossing behavior of the relevant transition energies, were clearly detected by electroreflectance spectroscopy and analyzed by calculating the Wannier‐Stark localization states as a function of electric field strength. It is found that the photocurrent‐voltage characteristics exhibit a peak structure, which results in a negative differential resistance, owing to a change of the optical transition probability under the resonant‐coupling condition between the first and second quantized electron states in adjacent quantum wells. Utilizing this negative differential resistance property, we have demonstrated a photocurrent‐bistability operation of a self‐electro‐optic effect device. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spectrally selective organic photodiodes
Authors: Lamprecht B. , Thünauer R. , Köstler S. , Jakopic G. , Leising G. , Krenn J. R. 
Published: May 2008

AbstractWe report on the fabrication of spectrally selective organic photodiodes (OPDs) and present a green sensitive OPD, whose spectral response peaks in the green region between 470 nm and 560 nm, as well as a red sensitive OPD whose spectral response peaks in the red region between 610 nm to 720 nm. We show that the spectral sensitivity of OPDs can be tuned by either choosing organic semiconductors with the appropriate photoresponse or by utilizing adequate device architectures with integrated optical filters. The results demonstrate the great flexibility of organic semiconductor materials. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Direct and Indirect Quantum Mechanical QSPR Hildebrand Solubility Parameter Models
Authors: Code James E. , Holder Andrew J. , Eick J. David 
Published: May 2008

AbstractThe objectives of this study were to develop Quantitative Structure–Property Relationship (QSPR) models to predict Hildebrand solubility parameters (δt). The study investigated direct δt prediction by QSPR and indirect δt calculation from QSPR‐predicted enthalpy of vaporization values. Molecular ground‐state minimum energy conformations were identified and optimized using the AM1 semiempirical Quantum Mechanical (QM) method. Predictive multiple linear regression models were derived correlating training set experimental solubility parameters or enthalpies of vaporization with descriptors obtained from the QM calculations. A four‐descriptor Hildebrand total solubility parameter regression equation was developed where R2=0.97, R$\rm{ {_{adj}^{2}}}$=0.97, F=461.5, s2=0.53, and Root Mean Square Error (RMSE)=0.69. A four‐descriptor QSPR model to predict enthalpies of vaporization (ΔHvap−kJ/mol) was constructed where R2=0.96, R$\rm{ {_{adj}^{2}}}$=0.96, F=230.3, s2=4.75, and RMSE=2.04. δt calculations from ΔHvap correlated well with literature δt , where R2=0.96. Both of these models are statistically significant as well as predictive. The direct and indirect δt models developed here compare favorably with liquid solubility parameter estimation accuracies (10%) reported by Hoftyzer–Van Krevelen and Hoy. These methods are useful for determining the miscibility of small organic molecules, an important consideration when formulating polymer blends.
Rapid classification of perfumes by extractive electrospray ionization mass spectrometry (EESI‐MS)
Authors: Chingin Konstantin , Gamez Gerardo , Chen Huanwen , Zhu Liang , Zenobi Renato 
Published: May 2008

AbstractExtractive electrospray ionization mass spectrometry (EESI‐MS) was applied to rapid fingerprinting of various perfumes for quality classification. Unique EESI‐MS fingerprints of ten famous brands were obtained. This technique was shown to be applicable to rapid forgery detection on the example of an authentic and a counterfeit ‘Miss Dior’ fragrance by Christian Dior. We believe that the high throughput and simplicity of this sample‐preparation‐free method can be advantageous in the perfume industry, for instance when applied to online quality control. Copyright © 2008 John Wiley & Sons, Ltd.
Measuring Epstein–Barr virus (EBV) load: the significance and application for each EBV‐associated disease
Authors: Kimura Hiroshi , Ito Yoshinori , Suzuki Ritsuro , Nishiyama Yukihiro 
Published: May 2008

AbstractBecause Epstein–Barr virus (EBV) is ubiquitous and persists latently in lymphocytes, simply detecting EBV is insufficient to diagnose EBV‐associated diseases. Therefore, measuring the EBV load is necessary to diagnose EBV‐associated diseases and to explore EBV pathogenesis. Due to the diverse biology of EBV, the significance of measuring EBV DNA and the optimal type of specimen differ among EBV‐associated diseases. Recent advances in molecular technology have enabled the EBV genome to be quantitated rapidly and accurately. Real‐time polymerase chain reaction (PCR) is a rapid and reliable method to quantify DNA and is widely used not only as a diagnostic tool, but also as a management tool for EBV‐associated diseases. However, each laboratory currently measures EBV load with its own “homebrew” system, and there is no consensus on sample type, sample preparation protocol, or assay units. The EBV real‐time PCR assay system must be standardised for large‐scale studies and international comparisons. Copyright © 2008 John Wiley & Sons, Ltd.
Apolipoprotein E4 domain interaction: Synaptic and cognitive deficits in mice
Authors: Zhong Ning , Scearce‐Levie Kimberly , Ramaswamy Gayathri , Weisgraber Karl H. 
Published: May 2008

BackgroundApolipoprotein E4 (apoE4), the major genetic risk factor for Alzheimer's disease (AD) and other neurodegenerative diseases, has three structural and biophysical properties that distinguish it from the other isoforms—domain interaction, reduced stability, and lack of cysteine. Assessing their relative contributions to effects of apoE4‐associated pathogenesis in AD is important from a mechanistic and therapeutic perspective, that is not possible using human apoE transgene or knock‐in models.MethodsWe analyzed Arg‐61 apoE mice, a gene‐targeted model that selectively displays domain interaction.ResultsThe mice displayed age‐dependent loss of the synaptic protein synaptophysin in neocortex and hippocampus and had lower levels of the postsynaptic neuroligin‐1. Activation of dentate gyrus granule neurons increased Arc expression 3.5‐fold in wildtype mice but only 2.3‐fold in Arg‐61 mice. The losses of synaptic proteins caused a mild memory deficit in Arg‐61 mice in the water‐maze test. Since synaptic integrity requires efficient glutamate uptake, we measured astrocyte glutamate transporter 1 in the hippocampus. The level was reduced in Arg‐61 mice, suggesting that inefficient glutamate uptake by astrocytes causes chronic excitotoxicity. Consistent with the reduced secretion of Arg‐61 apoE by astrocytes in this model, cholesterol secretion was also reduced 34%. This reduction could also contribute to the synaptic deficits by limiting the availability of cholesterol for neuronal repair.ConclusionsDomain interaction in the absence of other structural characteristics of apoE4 is sufficient to cause synaptic pathology and functional synaptic deficits, potentially associated with astrocyte dysfunction and impaired maintenance of neurons. Therapeutic targeting of domain interaction might blunt effects of apoE4 in neurodegenerative disease.
Immortal Fetuses
Authors: CUTAŞ DANIELA 
Published: May 2008

“Dissecting Bioethics,” edited by Tuija Takala and Matti Häyry, welcomes contributions on the conceptual and theoretical dimensions of bioethics.The section is dedicated to the idea that words defined by bioethicists and others should not be allowed to imprison people's actual concerns, emotions, and thoughts. Papers that expose the many meanings of a concept, describe the different readings of a moral doctrine, or provide an alternative angle to seemingly self-evident issues are therefore particularly appreciated.The themes covered in the section so far include dignity, naturalness, public interest, community, disability, autonomy, parity of reasoning, symbolic appeals, and toleration.All submitted papers are peer reviewed. To submit a paper or to discuss a suitable topic, contact Tuija Takala at tuija.takala@helsinki.fi.
Topology of three-manifolds with positive 𝑃-scalar curvature
Authors: Fan Edward 
Published: May 2008

Consider an

n
n

-dimensional smooth Riemannian manifold

(

M
n

,
g
)

(M^n,g)

with a given smooth measure

m
m

on it. We call such a triple

(

M
n

,
g
,
m
)

(M^n,g,m)

a Riemannian measure space. Perelman introduced a variant of scalar curvature in his recent work on solving Poincaré’s conjecture

P
(
g
)
=

R
∞
m

(
g
)
=
R
(
g
)
−
2

Δ
g

l
o
g
ϕ
−

|

∇
l
o
g
ϕ

|

g
2

P(g)=R^m_\infty (g) = R(g) - 2\Delta _g log\phi - |\nabla log\phi |^2_g

, where

d
m
=
ϕ
d
v
o
l
(
g
)

dm = \phi dvol(g)

and

R
R

is the scalar curvature of

(

M
n

,
g
)

(M^n,g)

. In this note, we study the topological obstruction for the

ϕ
\phi

-stable minimal submanifold with positive

P
P

-scalar curvature in dimension three under the setting of manifolds with density.
The Laplace transform of the digamma function: An integral due to Glasser, Manna and Oloa
Authors: Amdeberhan Tewodros , Espinosa Olivier , Moll Victor 
Published: May 2008

The definite integral

M
(
a
)
:=

4
π

∫

0

π

/

2

x

2

d
x

x

2

+

ln

2

⁡
(
2

e

−
a

cos
⁡
x
)

\begin{equation*} M(a):= \frac {4}{\pi } \int _{0}^{\pi /2} \frac {x^{2} \, dx } {x^{2} + \ln ^{2}( 2 e^{-a} \cos x ) }\end{equation*}

is related to the Laplace transform of the digamma function

L
(
a
)
:=

∫

0

∞

e

−
a
s

ψ
(
s
+
1
)

d
s
,

\begin{equation*} L(a) := \int _{0}^{\infty } e^{-a s} \psi (s+1) \, ds, \end{equation*}

by

M
(
a
)
=
L
(
a
)
+
γ

/

a

M(a) = L(a) + \gamma /a

when

a
>
ln
⁡
2

a > \ln 2

. Certain analytic expressions for

M
(
a
)

M(a)

in the complementary range,

0
>
a
≤
ln
⁡
2

0 > a \leq \ln 2

, are also provided.
Aligning LC peaks by converting gradient retention times to retention index of peptides in proteomic experiments
Authors: Shinoda Kosaku , Tomita Masaru , Ishihama Yasushi 
Published: May 2008

Abstract
Motivation: Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a powerful tool in proteomics studies, but when peptide retention information is used for identification purposes, it remains challenging to compare multiple LC-MS/MS runs or to match observed and predicted retention times, because small changes of LC conditions unavoidably lead to variability in retention times. In addition, non-contiguous retention data obtained with different LC-MS instruments or in different laboratories must be aligned to confirm and utilize rapidly accumulating published proteomics data.
Results: We have developed a new alignment method for peptide retention times based on linear solvent strength (LSS) theory. We found that log k0 (logarithm of retention factor for a given organic solvent) in the LSS theory can be utilized as a ‘universal’ retention index of peptides (RIP) that is independent of LC gradients, and depends solely on the constituents of the mobile phase and the stationary phases. We introduced a machine learning-based scheme to optimize the conversion function of gradient retention times (tg) to log k0. Using the optimized function, tg values obtained with different LC-MS systems can be directly compared with each other on the RIP scale. In an examination of Arabidopsis proteomic data, the vast majority of retention time variability was removed, and five datasets obtained with various LC-MS systems were successfully aligned on the RIP scale.
Contact: y-ishi@ttck.keio.ac.jp
MOCSphaser: a haplotype inference tool from a mixture of copy number variation and single nucleotide polymorphism data
Authors: Kato Mamoru , Nakamura Yusuke , Tsunoda Tatsuhiko 
Published: May 2008

Abstract
Summary: Detailed analyses of the population-genetic nature of copy number variations (CNVs) and the linkage disequilibrium between CNV and single nucleotide polymorphism (SNP) loci from high-throughput experimental data require a computational tool to accurately infer alleles of CNVs and haplotypes composed of both CNV alleles and SNP alleles. Here we developed a new tool to infer population frequencies of such alleles and haplotypes from observed copy numbers and SNP genotypes, using the expectation–maximization algorithm. This tool can also handle copy numbers ambiguously determined, such as 2 or 3 copies, due to experimental noise.
Availability: http://emu.src.riken.jp/MOCSphaser/MOCSphaser.zip
Contact: tsunoda@src.riken.jp
Supplementary information: Additional materials can be found at http://emu.src.riken.jp/MOCSphaser/SuppInfor.doc
Annual prey consumption of a dominant seabird, the common murre, in the California Current system
Authors: Roth Jennifer E. , Nur Nadav , Warzybok Pete , Sydeman William J. 
Published: May 2008

Abstract
Roth, J. E., Nur, N., Warzybok, P., and Sydeman, W. J. 2008. Annual prey consumption of a dominant seabird, the common murre, in the California Current system. – ICES Journal of Marine Science, 65: 1046–1056. Information compiled from the literature on population size, diet composition, field metabolic rate, prey energy densities, and assimilation efficiency is used to estimate annual prey consumption by common murres (Uria aalge), between Cape Blanco, OR, and Point Conception, CA, USA. The population consumed an estimated 172 313 t of prey based on population estimates and diet data from the mid- to the late 1980s, including 50 125 t consumed by breeding adults, 36 940 t by non-breeding birds during the breeding season, 85 098 t by all birds during the wintering period, and 150 t by dependent chicks before their leaving the breeding colonies. The population in the mid-2000s consumed 225 235 t of prey based on population estimates from 2004, including 65 516 t consumed by breeding adults, 48 283 t by non-breeding birds during the breeding season, 111 226 t by all birds during the wintering period, and 210 t by chicks at breeding colonies. Monte Carlo simulations indicated that the coefficients of variation around our overall prey consumption estimates were ±14.4% for the 1980s and ±13.2% for the 2000s.
Spatial and temporal prediction of fin whale distribution in the northwestern Mediterranean Sea
Authors: Laran Sophie , Gannier Alexandre 
Published: May 2008

AbstractLaran, S. and Gannier, A. 2008. Spatial and temporal prediction of fin whale distribution in the northwestern Mediterranean Sea. – ICES Journal of Marine Science, 65: 1260–1269. Understanding the distribution of the cetaceans is crucial to improving their conservation. Therefore, a prediction model of fin whale’s (Balaenoptera physalus) summer distribution was developed from data collected between May and August, in the Pelagos Mediterranean Marine Mammals Sanctuary. Explanatory variables were selected by multiple logistic regression, among several physiographic and oceanographic parameters. Depth, chlorophyll (Chl a) concentration, and sea surface temperature (SST) were selected for characterizing fin whale presence. Remote sensing imagery (Chl a and SST) was used at an 8-d resolution to capture short-term environmental variability. With the selection of a presence/absence threshold by the receiver operating characteristic curve, a correct classification of 70% (49% for presence, 85% for absence) was achieved for the initial dataset. Model reliability was also tested on an independent dataset, collected in the northwestern Basin; a correct classification of 71% (41% for presence prediction, 86% for absence prediction) was obtained. This study contributes to an understanding of where fin whales might concentrate to feed in summer. Weekly predictions of their distribution represent a valuable conservation tool in a marine protected area, for example to prevent collisions with ships.
Outbreak of Tomato yellow leaf curl virus (Family Geminiviridae) in Georgia
Authors: Pappu S. S. , Pappu H. R. , Langston D. B. , Flanders J. T. , Riley D. G. 
Published: May 2008

Tomato yellow leaf curl virus (TYLCV) of the family Geminiviridae is a serious production constraint to tomato. In the southeastern United States the virus has been largely confined to Florida. The disease appeared in the southern most Georgia county (Decatur) in 1998, at an incidence rate of less than 1%. During the fall of 1999, tomato plants showing symptoms indicative of TYLCV were observed in commercial fields in Grady, Colquitt, and Lowndes counties and the experimental plots of the Coastal Plain Experiment Station in two locations in Tift County, GA. Posted 1 June 2000.
Bacterial Fruit Blotch of Cucurbits
Authors: Latin R. X. 
Published: May 2008

Bacterial fruit blotch appeared in the United States in commercial watermelon fields with isolated severe outbreaks in Florida, South Carolina, and Indiana. Because the pathogen is seedborne, and a significant portion of commercial watermelon fields are planted with seedlings raised in greenhouses or other transplant production facilities, recognition of symptoms on seedlings is important. Posted 2 June 2000.