bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling gene networks at different organisational levels
Authors: Schlitt Thomas , Brazma Alvis
Published: February 2005

Approaches to modelling gene regulation networks can be categorized, according to increasing detail, as network parts lists, network topology models, network control logic models, or dynamic models. We discuss the current state of the art for each of these approaches. There is a gap between the parts list and topology models on one hand, and control logic and dynamic models on the other hand. The first two classes of models have reached a genome‐wide scale, while for the other model classes high throughput technologies are yet to make a major impact.
Re‐analysis of data and its integration
Authors: Jensen Lars Juhl , Steinmetz Lars M.
Published: February 2005

To understand a biological process it is clear that a single approach will not be sufficient, just like a single measurement on a protein – such as its expression level – does not describe protein function. Using reference sets of proteins as benchmarks different approaches can be scaled and integrated. Here, we demonstrate the power of data re‐analysis and integration by applying it in a case study to data from deletion phenotype screens and mRNA expression profiling.
From molecular networks to qualitative cell behavior
Authors: Gagneur Julien , Casari Georg
Published: February 2005

Adaptation and behavior are characteristics of life which are fundamentally dynamic. If we want to model the living cell we have to describe it as a dynamic system. Typical dynamic models are based on quantitative differential equations requiring very detailed kinetic knowledge. Alternative modeling techniques for less fine‐grained information are better suited to available functional genomics data. As such, constraint‐based techniques and qualitative modeling have proven themselves to be valid approaches in cell biology. These approaches offer formal support to check the consistency of molecular networks against phenotypic observations in the light of dynamic systems.
Space as the final frontier in stochastic simulations of biological systems
Authors: Lemerle Caroline , Di Ventura Barbara , Serrano Luis
Published: February 2005

Recent technological and theoretical advances are only now allowing the simulation of detailed kinetic models of biological systems that reflect the stochastic movement and reactivity of individual molecules within cellular compartments. The behavior of many systems could not be properly understood without this level of resolution, opening up new perspectives of using computer simulations to accelerate biological research. We review the modeling methodology applied to stochastic spatial models, also to the attention of non‐expert potential users. Modeling choices, current limitations and perspectives of improvement of current general‐purpose modeling/simulation platforms for biological systems are discussed.
Lower respiratory tract infection due to Capnocytophaga cynodegmi in a cat with pulmonary carcinoma
Authors: Forman Marnin A. , Johnson Lynelle R. , Jang Spencer , Foley Janet E.
Published: February 2005

A 10-year-old male castrated domestic shorthair cat was evaluated for coughing and lethargy. Thoracic radiographs revealed a soft tissue lung mass and diffuse peribronchial infiltrates. Bronchoscopy was performed and Capnocytophaga cynodegmi was cultured from bilateral bronchoalveolar lavage samples. Clinical signs and bacterial colonization resolved following treatment with enrofloxacin. A lung lobectomy was performed to remove the lung mass, which was diagnosed as pulmonary carcinoma. C cynodegmi is most frequently isolated from localized wound and corneal infections in humans. Specialized growth characteristics of C cynodegmi may result in low sensitivity for bacterial culture. To the authors' knowledge, this case represents the first report of C cynodegmi infection in a veterinary patient and only the second case in human or veterinary medicine where the organism has been isolated from a bronchoalveolar lavage sample. Based on this report, Capnocytophaga species should be considered as potential opportunistic pathogens.
Cutaneous lesions associated with coronavirus-induced vasculitis in a cat with feline infectious peritonitis and concurrent feline immunodeficiency virus infection
Authors: Cannon Martha J , Silkstone Malcolm A , Kipar Anja M
Published: February 2005

This report describes a clinical case of feline infectious peritonitis (FIP) with multisystemic involvement, including multiple nodular cutaneous lesions, in a cat that was co-infected with feline coronavirus and feline immunodeficiency virus. The skin lesions were caused by a pyogranulomatous-necrotising dermal phlebitis and periphlebitis. Immunohistology demonstrated the presence of coronavirus antigen in macrophages within these lesions.

The pathogenesis of FIP involves a viral associated, disseminated phlebitis and periphlebitis which can arise at many sites. Target organs frequently include the eyes, abdominal organs, pleural and peritoneal membranes, and central nervous tissues, but cutaneous lesions have not previously been reported.
The Anatomy Lesson of Dr Tulp
Authors: MASQUELET A. C.
Published: February 2005

The anatomy lesson of Dr Tulp is one of the most famous paintings by Rembrandt. A detailed examination of the scene leads us to believe that Dr Tulp was demonstrating the function of the flexor digitorum superficialis. Therefore, the painting is a true lesson in physiology which is in keeping with the spirit of the 17th century, which was the century in which the modern theory of movement in physics evolved. The anatomy lesson of Dr Tulp also symbolizes the break with the descriptive anatomy of Vesalius which occurred during this century.
Cosmogenic nuclide chronology of pre-last glacial maximum moraines at Lago Buenos Aires, 46�S, Argentina
Authors: Kaplan Michael R. , Douglass Daniel C. , Singer Bradley S. , Ackert Robert P. , Caffee Marc W.
Published: February 2005

At Lago Buenos Aires, Argentina, 10Be, 26Al, and 40Ar/39Ar ages range from 190,000 to 109,000 yr for two moraines deposited prior to the last glaciation, 23,000�16,000 yr ago. Two approaches, maximum boulder ages assuming no erosion, and the average age of all boulders and an erosion rate of 1.4 mm/103 yr, both yield a common estimate age of 150,000�140,000 yr for the two moraines. The erosion rate estimate derives from 10Be and 26Al concentrations in old erratics, deposited on moraines that are >760,000 yr old on the basis of interbedded 40Ar/39Ar dated lavas. The new cosmogenic ages indicate that a major glaciation during marine oxygen isotope stage 6 occurred in the mid-latitude Andes. The next five youngest moraines correspond to stage 2. There is no preserved record of a glacial advance during stage 4. The distribution of dated boulders and their ages suggest that at least one major glaciation occurred between 760,000 and >200,000 yr ago. The mid-latitude Patagonian glacial record, which is well preserved because of low erosion rates, indicates that during the last two glacial cycles major glaciations in the southern Andes have been in phase with growth and decay of Northern Hemisphere ice sheets, especially at the 100,000 yr periodicity. Thus, glacial maxima are global in nature and are ultimately paced by small changes in Northern Hemisphere insolation.
TIME AVERAGES FOR THE LAPLACE GROUP
Authors: Jackson Damian C.
Published: February 2005

The imaginary powers of the Laplace operator over the circle give a $C_0$ group of bounded linear operators on $\mathsf{L}_{\theta}^p(0,2\pi)$ ($1\ltp\lt\infty$). Whereas the group is unbounded on $\mathsf{L}^4$, this paper shows that the $\mathsf{L}^4$ long-time averages of each $f$ in $\mathsf{L}^2$ are bounded. This is a Fourier restriction phenomenon.

AMS 2000 Mathematics subject classification: Primary 42A15; 42B15
CLASSES OF OPERATOR-SMOOTH FUNCTIONS. I. OPERATOR-LIPSCHITZ FUNCTIONS
Authors: Kissin Edward , Shulman Victor S.
Published: February 2005

In this paper we study the spaces of operator-Lipschitz functions and the spaces of functions closed to them: commutator bounded. Apart from the standard operator norm on $B(H)$, we consider a rich variety of symmetric operator norms and spaces of operator-Lipschitz functions with respect to these norms. Our approach is aimed at the investigation of the interrelation and hierarchy of these spaces and of the intrinsic properties of operator-Lipschitz functions.

AMS 2000 Mathematics subject classification: Primary 47A56. Secondary 47L20
RADIAL AND TANGENTIAL GROWTH OF CLOSE-TO-CONVEX FUNCTIONS
Authors: Twomey J. B.
Published: February 2005

Some results are presented relating to questions raised in a recent paper by Anderson, Hayman and Pommerenke regarding the size of the set of boundary points of the unit disc at which a univalent function has a prescribed radial growth.

AMS 2000 Mathematics subject classification: Primary 30C55
APPLICATIONS OF DIVERGENCE POINTS TO LOCAL DIMENSION FUNCTIONS OF SUBSETS OF $\mathbb{R}^{d}$
Authors: Olsen L.
Published: February 2005

For a subset $E\subseteq\mathbb{R}^{d}$ and $x\in\mathbb{R}^{d}$, the local Hausdorff dimension function of $E$ at $x$ is defined by

$$ \mathrm{dim}_{\mathrm{loc}}(x,E)=\lim_{r\searrow0}\mathrm{dim}(E\cap B(x,r)), $$

where ‘dim’ denotes the Hausdorff dimension. Using some of our earlier results on so-called multifractal divergence points we give a short proof of the following result: any continuous function $f:\mathbb{R}^{d}\to[0,d]$ is the local dimension function of some set $E\subseteq\mathbb{R}^{d}$. In fact, our result also provides information about the rate at which the dimension $\mathrm{dim}(E\cap B(x,r))$ converges to $f(x)$ as $r\searrow0$.

AMS 2000 Mathematics subject classification: Primary 28A80
DUALIZING MODULES AND n-PERFECT RINGS
Authors: Enochs Edgar E. , Jenda Overtoun M. G. , López-Ramos J. A.
Published: February 2005

In this article we extend the results about Gorenstein modules and Foxby duality to a non-commutative setting. This is done in §3 of the paper, where we characterize the Auslander and Bass classes which arise whenever we have a dualizing module associated with a pair of rings. In this situation it is known that flat modules have finite projective dimension. Since this property of a ring is of interest in its own right, we devote §2 of the paper to a consideration of such rings. Finally, in the paper’s final section, we consider a natural generalization of the notions of Gorenstein modules which arises when we are in the situation of §3, i.e. when we have a dualizing module.

AMS 2000 Mathematics subject classification: Primary 16D20
WHEN IS A UNIT LOOP f-UNITARY?
Authors: Goodaire Edgar G. , Polcino Milies César
Published: February 2005

Let $L$ be an RA loop, that is, a loop whose loop ring in any characteristic is an alternative, but not associative, ring. Let $f:L\to\{\pm1\}$ be a homomorphism and, for $\alpha=\sum\alpha_\ell\ell\in\mathbb{Z}L$, define $\alpha^f=\sum f(\ell)\alpha_\ell\ell^{-1}$. Call $\alpha$ f-unitary if $\alpha^f=\alpha^{-1}$ or $\alpha^f=-\alpha^{-1}$. In this paper, we identify the RA loops $L$ with the property that all units in $\mathbb{Z}L$ are $f$-unitary. Along the way, we extend a famous theorem of Higman to a case still undecided in group rings.

AMS 2000 Mathematics subject classification: Primary 20N05. Secondary 17D05; 16S34; 16U60
JACOBIAN IDEALS AND THE NEWTON NON-DEGENERACY CONDITION
Authors: Bivià-Ausina Carles
Published: February 2005

In this paper we extract some conclusions about Newton non-degenerate ideals and the computation of Łojasiewicz exponents relative to this kind of ideal. This motivates us to study the Newton non-degeneracy condition on the Jacobian ideal of a given analytic function germ $f:(\mathbb{C}^n,0)\to(\mathbb{C},0)$. In particular, we establish a connection between Newton non-degenerate functions and functions whose Jacobian ideal is Newton non-degenerate.

AMS 2000 Mathematics subject classification: Primary 32S05. Secondary 57R45
SOLUTIONS FOR DOUBLY RESONANT NONLINEAR NON-SMOOTH PERIODIC PROBLEMS
Authors: Kyritsi Sophia Th. , Papageorgiou Nikolaos S.
Published: February 2005

We study a nonlinear second-order periodic problem driven by the scalar $p$-Laplacian with a non-smooth potential. We consider the so-called doubly resonant situation allowing complete interaction (resonance) with both ends of the spectral interval. Using variational methods based on the non-smooth critical-point theory for locally Lipschitz functions and an abstract minimax principle concerning linking sets we establish the solvability of the problem.

AMS 2000 Mathematics subject classification: Primary 34B15; 34C25
FREDHOLM AND PROPERNESS PROPERTIES OF QUASILINEAR ELLIPTIC SYSTEMS OF SECOND ORDER
Authors: Gebran Hicham G. , Stuart Charles A.
Published: February 2005

For a large class of subsets $\varOmega\subset\mathbb{R}^{N}$ (including unbounded domains), we discuss the Fredholm and properness properties of second-order quasilinear elliptic operators viewed as mappings from $W^{2,p}(\varOmega;\mathbb{R}^{m})$ to $L^{p}(\varOmega;\mathbb{R}^{m})$ with $N\ltp\lt\infty$ and $m\geq1$. These operators arise in the study of elliptic systems of $m$ equations on $\varOmega$. A study in the case of a single equation ($m=1$) on $\mathbb{R}^{N}$ was carried out by Rabier and Stuart.

AMS 2000 Mathematics subject classification: Primary 35J45; 35J60. Secondary 47A53; 47F05
THE CONWAY FUNCTION OF A SPLICE
Authors: Cimasoni David
Published: February 2005

We give a closed formula for the Conway function of a splice in terms of the Conway function of its splice components. As corollaries, we refine and generalize results of Seifert, Torres and Sumners-Woods.

AMS 2000 Mathematics subject classification: Primary 57M25
MULTIPLICATIVELY SPECTRUM-PRESERVING MAPS OF FUNCTION ALGEBRAS. II
Authors: Rao N. V. , Roy A. K.
Published: February 2005

Let $\mathcal{A}$ be a closed, point-separating sub-algebra of $C_0(X)$, where $X$ is a locally compact Hausdorff space. Assume that $X$ is the maximal ideal space of $\mathcal{A}$. If $f\in\mathcal{A}$, the set $f(X)\cup\{0\}$ is denoted by $\sigma(f)$. After characterizing the points of the Choquet boundary as strong boundary points, we use this equivalence to provide a natural extension of the theorem in [10], which, in turn, was inspired by the main result in [6], by proving the ‘Main Theorem’: if $\varPhi:\mathcal{A}\rightarrow\mathcal{A}$ is a surjective map with the property that $\sigma(fg)=\sigma(\varPhi(f)\varPhi(g))$ for every pair of functions $f,g\in\mathcal{A}$, then there is an onto homeomorphism $\varLambda:X\rightarrow X$ and a signum function $\epsilon(x)$ on $X$ such that

$$ \varPhi(f)(\varLambda(x))=\epsilon(x)f(x) $$

for all $x\in X$ and $f\in\mathcal{A}$.

AMS 2000 Mathematics subject classification: Primary 46J10; 46J20
CRITICAL EXPONENTS FOR A REACTION–DIFFUSION MODEL WITH ABSORPTIONS AND COUPLED BOUNDARY FLUX
Authors: Zheng Sining , Li Fengjie
Published: February 2005

This paper deals with a reaction–diffusion model with inner absorptions and coupled nonlinear boundary conditions of exponential type. The critical exponents are described via a pair of parameters that satisfy a certain matrix equation containing all the six nonlinear exponents of the system. Whether the solutions blow up or not is determined by the signs of the two parameters. A more precise analysis, depending on the geometry of $\varOmega$ and the absorption coefficients, is proposed for the critical sign of the parameters.

AMS 2000 Mathematics subject classification: Primary 35K55; 35B33
THĀBIT IBN QURRA ET LA THÉORIE DES PARALLÈLES
Authors: RASHED ROSHDI , HOUZEL CHRISTIAN
Published: February 2005

Deux opuscules nous sont parvenus de Thābit ibn Qurra sur la théorie des parallèles. Ces deux traités sont bien connus et ont fait déjà l'objet de plusieurs commentaires et traductions. Nous pensons reprendre ici aussi bien l'édition que la traduction et le commentaire pour mieux situer la contribution de Thābit ibn Qurra après la publication récente de ses œuvres en astronomie et en mathématiques.
FROM AL-GHAZĀLĪ TO AL-RĀZĪ: 6TH/12TH CENTURY DEVELOPMENTS IN MUSLIM PHILOSOPHICAL THEOLOGY
Authors: SHIHADEH AYMAN
Published: February 2005

According to Tāj al-Dīn al-Subkī (d. 771 / 1370), al-Ghazālī (d. 505 / 1111) was the renewer (mujaddid) of the Muslim faith at the end of the 5th / 11th century, whereas al-Rāzī (d. 606 /1210) was the renewer of faith at the end of the 6th / 12th century. That al-Ghazālī deserves such an honour can hardly be disputed, and his importance in the history of Islamic thought is generally recognised. However, the same cannot, as easily, be said of al-Rāzī, whose historical significance is far from being truly appreciated, and some of the most important books of whom still await publication. Much is known about his views on particular philosophical and theological problems, and about the historical backgrounds to, and the relations amongst, some of these views. Some rather general observations on his thought are also common; for instance, that he is a heavily philosophising Ash‘arī mutakallim, a master dialectician, and an influential critic of Ibn Sīnā.
Neogene to Quaternary rifting and inversion in Corsica: Retreat and collision in the western Mediterranean
Authors: Fellin Maria Giuditta , Picotti Vincenzo , Zattin Massimiliano
Published: February 2005

Stratigraphic, structural, and fission track data have been integrated in order to unravel the Neogene to Quaternary tectonic evolution of northeastern Corsica. Results indicate that during early to middle Miocene the study area was affected by a rapid cooling at low temperatures accompanied by exhumation and rifting. Basin inversion occurred during the Tortonian, again followed by extension in the Messinian to early Pliocene. Compressional deformations are finally recorded by early Pliocene to Quaternary deposits. Alternating rifting and inversion events are recorded not only in northeastern Corsica but also in many peri‐Tyrrhenian regions. This alternation can be explained in terms of intraplate propagation of the compressional stress related to the Africa‐Europe convergence and to a discontinuous slab retreat along the Apennine subduction system. A pause in the slab retreat implies a break of the back arc extension in the upper plate, and it allows a temporary propagation of Africa‐Europe compression.
Influences of boreal fire emissions on Northern Hemisphere atmospheric carbon and carbon monoxide
Authors: Kasischke Eric S. , Hyer Edward J. , Novelli Paul C. , Bruhwiler Lori P. , French Nancy H. F. , Sukhinin Anatoly I. , Hewson Jennifer H. , Stocks Brian J.
Published: February 2005

There were large interannual variations in burned area in the boreal region (ranging between 3.0 and 23.6 × 106 ha yr−1) for the period of 1992 and 1995–2003 which resulted in corresponding variations in total carbon and carbon monoxide emissions. We estimated a range of carbon emissions based on different assumptions on the depth of burning because of uncertainties associated with the burning of surface‐layer organic matter commonly found in boreal forest and peatlands, and average total carbon emissions were 106–209 Tg yr−1 and CO emissions were 33–77 Tg CO yr−1. Burning of ground‐layer organic matter contributed between 46 and 72% of all emissions in a given year. CO residuals calculated from surface mixing ratios in the high Northern Hemisphere (HNH) region were correlated to seasonal boreal fire emissions in 8 out of 10 years. On an interannual basis, variations in area burned explained 49% of the variations in HNH CO, while variations in boreal fire emissions explained 85%, supporting the hypotheses that variations in fuels and fire severity are important in estimating emissions. Average annual HNH CO increased by an average of 7.1 ppb yr−1 between 2000 and 2003 during a period when boreal fire emissions were 26 to 68 Tg CO−1 higher than during the early to mid‐1990s, indicating that recent increases in boreal fires are influencing atmospheric CO in the Northern Hemisphere.
A Cenozoic diffuse alkaline magmatic province (DAMP) in the southwest Pacific without rift or plume origin
Authors: Finn Carol A. , Müller R. Dietmar , Panter Kurt S.
Published: February 2005

Common geological, geochemical, and geophysical characteristics of continental fragments of East Gondwana and adjacent oceanic lithosphere define a long‐lived, low‐volume, diffuse alkaline magmatic province (DAMP) encompassing the easternmost part of the Indo‐Australian Plate, West Antarctica, and the southwest portion of the Pacific Plate. A key to generating the Cenozoic magmatism is the combination of metasomatized lithosphere underlain by mantle at only slightly elevated temperatures, in contrast to large igneous provinces where mantle temperatures are presumed to be high. The SW Pacific DAMP magmatism has been conjecturally linked to rifting, strike‐slip faulting, mantle plumes, or hundreds of hot spots, but all of these associations have flaws. We suggest instead that sudden detachment and sinking of subducted slabs in the late Cretaceous induced Rayleigh‐Taylor instabilities along the former Gondwana margin that in turn triggered lateral and vertical flow of warm Pacific mantle. The interaction of the warm mantle with metasomatized subcontinental lithosphere that characterizes much of the SW Pacific DAMP concentrates magmatism along zones of weakness. The model may also provide a mechanism for warming south Pacific mantle and resulting Cenozoic alkaline magmatism, where the oceanic areas are characterized primarily, but not exclusively, by short‐lived hot spot tracks not readily explained by conventional mantle plume theory. This proposed south Pacific DAMP is much larger and longer‐lived than previously considered.
Characteristics of meteorological parameters associated with Hurricane Isabel
Authors: Gautam R. , Cervone G. , Singh R. P. , Kafatos M.
Published: February 2005

The present study focuses on the air‐sea interactions associated with Hurricane Isabel, which landed on the east coast of the United States on September 18, 2003. Hurricane Isabel is considered to be one of the most significant and severe tropical cyclones, as it affected the entire east coast in many ways. We have analyzed various meteorological parameters associated with the hurricane in different stages such as evolution, intensification and landfall. Analysis of surface latent heat flux (SLHF) and precipitation rate (PR) associated with the hurricane, based on the categorization in different stages, is carried out. SLHF and PR increase anomalously prior to landfall as compared to when the hurricane was at its maximum intensity (category 5). Wind speed (WS) and rain‐rate data from satellite observations show breakup of the eye‐wall and asymmetric structure leading to increased precipitation prior to landfall.
Extent and duration of the 2003 Cascadia slow earthquake
Authors: Melbourne Timothy I. , Szeliga Walter M. , Miller M. Meghan , Santillan V. Marcelo
Published: February 2005

Inversion of continuous GPS measurements from the Pacific Northwest show the 2003 Cascadia slow earthquake to be among the largest of ten transients recognized here. Twelve stations bracketing slow slip indicate transient slip propagated bi‐directionally from initiation in the southern Puget basin, reaching 300 km along‐strike over a period of seven weeks. This event produced, for the first time, resolvable vertical subsidence, and horizontal displacement reaching six mm in southern Washington State. Inverted for non‐negative thrust slip, a maximum of 3.8 cm of slip is inferred, centered at 28 km depth near the sharp arch in the subducting Juan de Fuca plate. Nearly all slip lies shallower than 38 km. Inverted slip shows a total moment release equal to Mw = 6.6 and a high degree of spatial localization rather than near‐uniform slip. This suggests rupture concentrated along asperities holds for slow earthquakes as well as conventional events.
A hypothesis for delayed dynamic earthquake triggering
Authors: Parsons Tom
Published: February 2005

It's uncertain whether more near‐field earthquakes are triggered by static or dynamic stress changes. This ratio matters because static earthquake interactions are increasingly incorporated into probabilistic forecasts. Recent studies were unable to demonstrate all predictions from the static‐stress‐change hypothesis, particularly seismicity rate reductions. However, current dynamic stress change hypotheses do not explain delayed earthquake triggering and Omori's law. Here I show numerically that if seismic waves can alter some frictional contacts in neighboring fault zones, then dynamic triggering might cause delayed triggering and an Omori‐law response. The hypothesis depends on faults following a rate/state friction law, and on seismic waves changing the mean critical slip distance (Dc) at nucleation zones.
Dominant patterns of AVHRR NDVI interannual variability over the Sahel and linkages with key climate signals (1982–2003)
Authors: Jarlan L. , Tourre Y. M. , Mougin E. , Philippon N. , Mazzega P.
Published: February 2005

The spatio‐temporal evolution of Sahelian vegetation is analyzed using the Normalized Difference Vegetation Index (NDVI) obtained from the NOAA/AVHRR sensor (1982–2003). Dominant patterns are identified using rotated EOFs. While the first four modes are associated with specific bio‐geo‐climatic conditions in space, significant time scales are detected using a multi‐tapers method. Three interannual time scales (∼6.2‐, 4.5‐ and 3.6‐year) are present in the first and third NDVI modes over the western Sahel. A quasi‐biennial time scale (∼2.6‐year) is present in second and fourth NDVI modes over the northeast Sahel. During summer, significant lagged correlations are found between the NDVI second (9‐month lag) and third (10‐month lag) modes, the meridional Atlantic Sea Surface Temperature (SST) gradient, and the zonal SST gradient in the Indian Ocean. Potential physical linkages and dynamics with known climate fluctuations are discussed.
Monthly temperature, salinity, and transport variability of the Bering Strait through flow
Authors: Woodgate Rebecca A. , Aagaard Knut , Weingartner Thomas J.
Published: February 2005

The Bering Strait through flow is important for the Chukchi Sea and the Arctic and Atlantic oceans. A realistic assessment of through flow properties is also necessary for validation and boundary conditions of high‐resolution ocean models. From 14 years of moored measurements, we construct a monthly climatology of temperature, salinity and transport. The strong seasonality in all properties (∼31.9 to 33 psu, ∼−1.8 to 2.3°C and ∼0.4 to 1.2 Sv) dominates the Chukchi Sea hydrography and implies significant seasonal variability in the equilibrium depth and ventilation properties of Pacific waters in the Arctic Ocean. Interannual variability is large in temperature and salinity. Although missing some significant events, an empirical linear fit to a local (model) wind yields a reasonable reconstruction of the water velocity, and we use the coefficients of this fit to estimate the magnitude of the Pacific‐Arctic pressure‐head forcing of the Bering Strait through flow.
Are there spurious precipitation trends in the United States Climate Division database?
Authors: Keim Barry D. , Fischer Michelle Russo , Wilson Adam M.
Published: February 2005

The United States Climate Division datasets (CDD) may contain spurious precipitation trends, induced by the method in which climate divisional data are created. This study investigated how the redistribution of stations within a climate division has affected purported annual trends in precipitation. CDD were compared to USHCN data for the 15 climate divisions of New England. Results showed that trends in the datasets are not always the same. We conclude that changing mean latitude, longitude, and elevation of stations within a division through time can affect, and even induce, trends in the time series. Trends found here were mostly increasing through time, but rates of change differed dramatically in some cases. Two climate divisions did have opposing trends between datasets. It appears that other factors, such as distance from the coast and changing slope direction (aspect) of stations, may also influence these trends.
Solar wind spatial scales in and comparisons of hourly Wind and ACE plasma and magnetic field data
Authors: King J. H. , Papitashvili N. E.
Published: February 2005

Hourly averaged interplanetary magnetic field (IMF) and plasma data from the Advanced Composition Explorer (ACE) and Wind spacecraft, generated from 1 to 4 min resolution data time‐shifted to Earth have been analyzed for systematic and random differences. ACE moments‐based proton densities are larger than Wind/Solar Wind Experiment (SWE) fits‐based densities by up to 18%, depending on solar wind speed. ACE temperatures are less than Wind/SWE temperatures by up to ∼25%. ACE densities and temperatures were normalized to equivalent Wind values in National Space Science Data Center's creation of the OMNI 2 data set that contains 1963–2004 solar wind field and plasma data and other data. For times of ACE‐Wind transverse separations <60 RE, random differences between Wind values and normalized ACE values are ∼0.2 nT for ∣B∣, ∼0.45 nT for IMF Cartesian components, ∼5 km/s for flow speed, and ∼15 and ∼30% for proton densities and temperatures. These differences grow as a function of transverse separation more rapidly for IMF parameters than for plasma parameters. Autocorrelation analyses show that spatial scales become progressively shorter for the parameter sequence: flow speed, IMF magnitude, plasma density and temperature, IMF X and Y components, and IMF Z component. IMF variations have shorter scales at solar quiet times than at solar active times, while plasma variations show no equivalent solar cycle dependence.
Deep current measurements at 38°N east of Japan
Authors: Fujio Shinzou , Yanagimoto Daigo
Published: February 2005

Deep currents east of Japan were investigated using direct current measurements and hydrographic observations. Current data, recorded for 9 months along 38°N, showed a pair of currents, one southward and the other northward, flowing along local isobaths above the western and eastern flanks. respectively, of the Japan Trench. Geostrophic velocities calculated from conductivity‐temperature‐depth (CTD) data showed a similar velocity pattern to the current measurements. The transports referring to the mean current velocities were estimated. Below 2000 m, the deep transports above the trench were southward 5.5 Sv and northward 13.5 Sv, and the boundary was at the deepest point of the trench. The mean current measured above the abyssal plain to the east of the trench was westward at 38°N. Since the bottom water properties above the eastern flank of the trench were colder and more saline than those on the abyssal plain, the westward current does not enter the trench but rather is expected to turn northward just east of the trench. Its northward transport was estimated to be 6.2 Sv, and the total northward transport was estimated to be 19.7 Sv at 38°N. A pair of oppositely flowing deep currents is confirmed in the Japan Trench. While the transports were similar to those of the Izu‐Ogasawara and Kuril‐Kamchatka trenches, whose ends connect with the Japan Trench, the current structure resembles that at the Izu‐Ogasawara Trench rather than that at the Kuril‐Kamchatka Trench.
Slope water, Gulf Stream, and seasonal influences on southern Mid‐Atlantic Bight circulation during the fall‐winter transition
Authors: Rasmussen L. L. , Gawarkiewicz G. , Owens W. B. , Lozier M. S.
Published: February 2005

Observations from autumn 2000 near the shelfbreak front in the Middle Atlantic Bight are used to describe the transition from stratified summer conditions to well‐mixed winter conditions over the shelf. During the observational period, the front differed dramatically from climatological conditions, with buoyant Gulf Stream water found shoreward over the subsurface shelfbreak front. Water mass analysis shows a large number of separate water masses with shelf, slope, and Gulf Stream origins. The coolest shelf water was located at the shelfbreak and may be related to “cold pool” water masses observed to the north during summer. Shoreward of this shelfbreak water mass, a mid‐shelf front was present which intersected the bottom at the 50‐m isobath. High‐volume transports were associated with both the shelfbreak and mid‐shelf fronts. Transport estimates from the cross‐shelf sections were approximately 1 Sverdrup, which is large relative to previous estimates of shelf transport. The foot of the front was near the 130‐m isobath, much deeper than the climatological position near the 75‐m isobath; however, this is consistent with a recent theory relating the magnitude of alongshelf transport to the depth at which the front intersects the bottom.
Laboratory study of the fine structure of short surface waves due to breaking: Two‐directional wave propagation
Authors: Rozenberg A. , Ritter M.
Published: February 2005

This study was stimulated by the need to identify the influence of breaking on the evolution of the short surface wave field responsible for microwave scattering. Laboratory measurements of the fine space‐time structure of short gravity‐capillary waves and Ku band scattering at grazing and moderate incidence from spilling and plunging breaking waves in a laboratory wave channel are presented. Unsteady breaking waves are generated by focusing wave groups in space‐time domains. A scanning laser slope gauge was used for measuring capillary‐gravity waves with wavelengths of 2 mm to 10 cm and frequency ranges of up to 150 Hz. A dual polarized (VV, HH) coherent pulsed Ku band scatterometer with a 3 ns temporal resolution was used to simultaneously obtain Doppler spectra of the scattered signals from the breaking area for grazing angles from 6° to 25°. Two‐dimensional filtering in the wave number‐frequency plane as well as plus/minus Doppler spectra were used to separate the direction of propagation of the surface waves within the breaking region. It was found that the breaking splash is the main source of the surface wave generation. The short surface wave slope field produced by breaking could be separated into short (4–8 mm wavelength), fast waves and free gravity‐capillary waves. Both types of waves were found to be co‐ and counterpropagate relative to the dominant wave propagation direction. The Doppler spectrograms reveal the presence of high‐frequency waves at the moment of breaking that can be associated with short, fast waves. The low‐frequency part of the Doppler spectrogram is consistent with the appearance of free waves.
Earth‐based observations of radar‐dark crater haloes on the Moon: Implications for regolith properties
Authors: Ghent Rebecca R. , Leverington David W. , Campbell Bruce A. , Hawke B. Ray , Campbell Donald B.
Published: February 2005

Earth‐based radar can be used in conjunction with other data sets collected remotely or in situ to characterize the physical and chemical properties of the lunar regolith. We use previously existing and newly acquired Earth‐based radar measurements at 70‐cm wavelength to investigate the properties of distinctive low‐return haloes surrounding 39 nearside impact craters. These haloes are distinct from the well‐known optically dark haloes associated with volcanic craters or with impacts into cryptomare deposits. We examine two possible mechanisms for formation of radar‐dark haloes: (1) excavation of high‐TiO2, high‐loss tangent basalt and (2) deposition of a mantling layer produced in the impact process that is depleted in meter‐sized blocks. Comparison of the radar data with Apollo and Lunar Orbiter images indicates a general spatial correspondence between radar‐dark crater haloes and radial ridged ejecta facies distal to the radar‐bright crater rims. Comparison with Clementine UV/VIS multispectral data indicates no apparent spatial correlation between regions of enhanced TiO2 content and radar‐dark haloes; though variations in TiO2 content may play a role for some mare craters, they are insufficient to account for the observed offsets in radar echo power. We conclude that the radar‐dark haloes result from a block‐poor ejecta deposit that disappears over time with meteoroid bombardment. A more detailed and comprehensive analysis of ejecta degradation processes and rates following acquisition of additional high‐resolution radar data could lead to a refinement of the lunar geologic timescale.
The economic value of stream restoration
Authors: Collins Alan , Rosenberger Randy , Fletcher Jerald
Published: February 2005

The economic value of restoring Deckers Creek in Monongalia and Preston counties of West Virginia was determined from mail, Internet, and personal contact surveys. Multiattribute, choice experiments were conducted and nested logit models were estimated to derive the economic values of full restoration for three attributes of this creek: aquatic life, swimming, and scenic quality. Their relative economic values were that aquatic life > scenic quality ≈ swimming. These economic values imply that respondents had the highest value for aquatic life when fully restoring Deckers Creek to a sustainable fishery rather than a “put and take” fishery that cannot sustain fish populations. The welfare improvement estimates for full restoration of all three attributes ranged between $12 and $16 per month per household. Potential stream users (anglers) had the largest welfare gain from restoration, while nonangler respondents had the lowest. When these estimates were aggregated up to the entire watershed population, the benefit from restoration of Deckers Creek was estimated to be about $1.9 million annually. This benefit does not account for any economic values from partial stream restoration. On the basis of log likelihood tests of the nested logit models, two subsamples of the survey population (the general population and stream users) were found to be from the same population. Thus restoration choices by stream users may be representative of the watershed population, although the sample size of stream users was small in this research.
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Wigner–Racah algebra for the matrix of second moments of embedded Gaussian unitary ensemble of random matrices
Authors: Kota V. K. B.
Published: February 2005

Recently Pluhar and Weidenmüller [Ann. Phys. (N.Y.) 297, 344 (2002)] showed that the eigenvectors of the matrix of second moments of embedded Gaussian unitary ensemble of random matrices generated by k-body interactions [EGUE(k)] for m fermions in N single particle states are SU(N) Wigner coefficients and derived also an expression for the eigenvalues. Going beyond this work, we will show that the eigenvalues of this matrix are square of a SU(N) Racah coefficient and thus the matrix of second moments of EGUE(k) is solved completely by SU(N) Wigner–Racah algebra.
Exact solution to a supersymmetric Gaudin model
Authors: Breiderhoff Julia , Musso Fabio , Ragnisco Orlando
Published: February 2005

We investigate a special case of the Gaudin model related to the superalgebra osp(1,2). We present an exact solution to that system diagonalizing a complete set of commuting observables, and providing the corresponding eigenvectors and eigenvalues. The approach used in this paper is based on the co-algebra symmetry of the model, already known from the Calogero–Gaudin system.
Nonlinear dust phase-space vortices (holes) in charge-varying dusty plasmas
Authors: Tribeche Mouloud , Aoutou Kamel , Zerguini Taha Houssine
Published: February 2005

The recent analysis of dust voids [A. A. Mamun and P. K. Shukla, Phys. Plasmas 11, 1757 (2004)] is extended to include self-consistently the dust charge variation. Numerical solutions of highly nonlinear equations are carried out including dust charging and dust trapping. It is found that under certain conditions the effect of dust charge variation can be quite important. In particular, it may be noted that the dust charge variation leads to an additional enlargement of the nonlinear dust voids. The effects of ion/electron temperature, trapping parameter, and dust size on the properties of these nonlinear dust voids are briefly discussed.
Hall effect on relaxation process of flowing plasmas
Authors: Ohsaki Shuichi
Published: February 2005

The Hall effect on the nonlinear dynamics of a flowing plasma has been studied by comparing the magnetohydrodynamics (MHD) equations and the Hall MHD equations. Numerical simulations of both systems show that the turbulence brings about dissipation of the magnetic and kinetic (flow) energies, and self-organization of large-scale structures occurs. However, the perpendicular flow to the magnetic field is generated more effectively and the kinetic energy dissipates much faster in the Hall MHD system. The enhanced energy dissipation is primarily due to the production of small-scale fluctuations, which proves the creation of scale hierarchy by the singular perturbation of the Hall effect.
Equilibrium of an electron plasma confined on magnetic surfaces
Authors: Boozer Allen H.
Published: February 2005

The difficulty in solving the equation for the electrostatic equilibrium of a pure electron plasma confined on magnetic surfaces can be reduced by separately solving for a part of the electric potential that is constant on the magnetic surfaces. Freedom exists in the choice for the constant part of the potential. Here a particular choice and how it simplifies the solution of the the electrostatic equilibrium problem are discussed.
Darboux transformations and exact solutions of two dimensional A2n(2) Toda equation
Authors: Zhou Zi-Xiang
Published: February 2005

The Darboux transformations for two dimensional A2n(2) Toda equation are constructed. The lowest degree of the Darboux transformation is 2(2n+1) if all the spectral parameters are complex, or 2n+1 if one spectral parameter is real. Exact solutions are written down by computing the Darboux transformations explicitly.
Higher-order nonlinearity of electron-acoustic solitary waves with vortex-like electron distribution and electron beam
Authors: El-Taibany W. F. , Moslem Waleed M.
Published: February 2005

The nonlinear wave structure of small-amplitude electron-acoustic solitary waves (EASWs) is investigated in a four-component plasma consisting of cold electron fluid, hot electrons obeying vortex-like distribution traversed by a warm electron beam and stationary ions. The streaming velocity of the beam, uo, plays the dominant role in determining the roots of the linear dispersion relation associated with the system. Using the reductive perturbation theory, the basic set of equations is reduced to a modified Korteweg–de Vries (mKdV) equation. With the inclusion of higher-order nonlinearity, a linear inhomogeneous mKdV type equation with fifth-order dispersion term is derived and the higher-order solution is obtained using a renormalization method. However, both mKdV and mKdV-type solutions present a positive potential, which corresponds to a hole (hump) in the cold (hot) electron number density. The mKdV-type solution has a smaller energy amplitude and a wider width than that of mKdV solution. The dependence of the energy amplitude, the width, and the velocity on the system parameters is investigated. The findings of this investigation are used to interpret the electrostatic solitary waves observed by the Geotail spacecraft in the plasma sheet boundary layer of the Earth’s magnetosphere.
A dynamic nonlinear subgrid-scale stress model
Authors: Wang Bing-Chen , Bergstrom Donald J.
Published: February 2005

In this paper, a dynamic subgrid scale (SGS) stress model based on Speziale’s quadratic nonlinear constitutive relation [C. G. Speziale, J. Fluid Mech. 178, 459 (1987); T. B. Gatski and C. G. Speziale, J. Fluid Mech. 254, 59 (1993)] is proposed, which includes the conventional dynamic SGS model as its first-order approximation. The closure method utilizes both the symmetric and antisymmetric parts of the resolved velocity gradient, and allows for a nonlinear anisotropic representation of the SGS stress tensor. Unlike the conventional Smagorinsky type modeling approaches, the proposed model does not require an alignment between the SGS stress tensor and the resolved strain rate tensor. It exhibits significant flexibility in self-calibration of the model coefficients, and local stability without the need for plane averaging to avoid excessive backscatter of SGS turbulence kinetic energy and potential modeling singularity problems. It also allows for variable tensorial geometric relations between the SGS stress and its constituent terms, and reflects both forward and backward scatters of SGS turbulence kinetic energy between the filtered and subgrid scales of motions. Turbulent Couette flow for Reynolds numbers (based on channel height and one half the velocity difference between the two plates) of 2600 and 4762 was used in numerical simulations to validate the proposed approach.
On the Rayleigh–Bénard problem in the continuum limit
Authors: Manela Avshalom , Frankel Itzchak
Published: February 2005

The transition to convection in the Rayleigh–Bénard problem at small Knudsen numbers is studied via a linear temporal stability analysis of the compressible “slip-flow” problem. No restrictions are imposed on the magnitudes of temperature difference and compressibility-induced density variations. The dispersion relation is calculated by means of a Chebyshev collocation method. The results indicate that occurrence of instability is limited to small Knudsen numbers (Kn≲0.03) as a result of the combination of the variation with temperature of fluid properties and compressibility effects. Comparison with existing direct simulation Monte Carlo and continuum nonlinear simulations of the corresponding initial-value problem demonstrates that the present results correctly predict the boundaries of the convection domain. The linear analysis thus presents a useful alternative in studying the effects of various parameters on the onset of convection, particularly in the limit of arbitrarily small Knudsen numbers.
High-efficiency light-emitting diodes using neutral surfactants and aluminum cathode
Authors: Niu Yu-Hua , Ma Hong , Xu Qingmin , Jen Alex K.-Y.
Published: February 2005

High-efficiency polymer light-emitting diodes were fabricated by spin-coating a layer of neutral surfactant on top of the poly[2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene] electroluminescent (EL) layer to facilitate the electron injection through the high-work-function aluminum cathode. The external luminous efficiency of the device can reach 3.59 cd/A, which is higher than the control device (1.89 cd/A) using calcium as cathode. It was found that when the combination of surfactant and aluminum was used as cathode the abundant hole-injection through a hole-transporting layer and hole pile-up at the inner side of the EL/surfactant interface causes an effective electric field to enhance electron injection.
Pyroelectric properties of [111]-oriented Pb(Mg1∕3Nb2∕3)O3–PbTiO3 crystals
Authors: Tang Yanxue , Zhao Xiangyong , Feng Xiqi , Jin Weiqing , Luo Haosu
Published: February 2005

The pyroelectric properties of [111]-oriented Pb(Mg1∕3Nb2∕3)O3–0.29PbTiO3 (PMN-0.29PT) crystals have been investigated both as a function of frequency and temperature. At room temperature, [111]-oriented crystals have a high pyroelectric coefficient of 12.8×10−4C∕m2K and a low thermal diffusivity of ∼3.7×10−7m2∕s. The calculated voltage responsivity and detectivity figures of merit Fv and Fd exceed 0.11m2∕C and 9.8×10−5Pa−1∕2, respectively, over a wide range of frequency from 50 to 20000 kHz. The crystals are inert in practical application environment and can be easily processed as well. Such investigation reveals that superior pyroelectric performance makes PMN-0.29PT crystals a promising candidate for uncooled infrared detectors and imagers.