bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Index of Interannual Precipitation Variability in the Core of the North American Monsoon Region
Authors: Gutzler David S. 
Published: November 2004

Abstract
Seasonal precipitation anomalies associated with the continental North American monsoon system are characterized using a land-based dataset derived from in situ observations across the southwestern United States and northwestern Mexico. Coherent regions of interannual continental precipitation variability are derived from principal component analysis, after defining separate “early” and “late” summer monsoon seasons. The gravest mode of late-season interannual variability captures precipitation anomalies in the core of the continental monsoon domain. A simple spatial average is developed as an index of this core variability. The seasonal separation allows examination of persistence of precipitation anomalies as an indicator of practical late-season predictability. Possible influences of large-scale oceanic interannual fluctuations [ENSO and Pacific decadal oscillation (PDO)] on core index precipitation anomalies are also considered. The core precipitation index exhibits considerably more early-to-late-season persistence than an ocean-centered precipitation index. Implications of these results for monthly/seasonal predictability of warm-season precipitation are discussed.
Taking China's Temperature: Daily Range, Warming Trends, and Regional Variations, 1955–2000
Authors: Liu Binhui , Xu Ming , Henderson Mark , Qi Ye , Li Yiqing 
Published: November 2004

Abstract
In analyzing daily climate data from 305 weather stations in China for the period from 1955 to 2000, the authors found that surface air temperatures are increasing with an accelerating trend after 1990. They also found that the daily maximum (Tmax) and minimum (Tmin) air temperature increased at a rate of 1.27° and 3.23°C (100 yr)−1 between 1955 and 2000. Both temperature trends were faster than those reported for the Northern Hemisphere, where Tmax and Tmin increased by 0.87° and 1.84°C (100 yr)−1 between 1950 and 1993. The daily temperature range (DTR) decreased rapidly by −2.5°C (100 yr)−1 from 1960 to 1990; during that time, minimum temperature increased while maximum temperature decreased slightly. Since 1990, the decline in DTR has halted because Tmax and Tmin increased at a similar pace during the 1990s. Increased minimum and maximum temperatures were most pronounced in northeast China and were lowest in the southwest. Cloud cover and precipitation correlated poorly with the decreasing temperature range. It is argued that a decline in solar irradiance better explains the decreasing range of daily temperatures through its influence on maximum temperature. With declining solar irradiance even on clear days, and with decreases in cloud cover, it is posited that atmospheric aerosols may be contributing to the changing solar irradiance and trends of daily temperatures observed in China.
A New Hydrothermal Route to Prism-shaped CuSeO3·2H2O Single Crystals
Authors: Cui Jianhua , Guo Fan , Liu Xinzheng 
Published: November 2004

Abstract
Prism-shaped CuSeO3·2H2O single crystals, with sizes of 0.64–0.77 × 0.45–0.67 × 0.26–0.33 mm, were synthesized via a new hydrothermal reaction of CuCl2·2H2O and Se powder in aqueous ammonia at 180 °C. The double crystal X-ray diffraction rocking curve shows that the single crystals have high quality. And optimum conditions for the growth of CuSeO3·2H2O single crystals are discussed.
A Key Role of Orbital Interaction in the Main Group Element-containing π-Electron Systems
Authors: Yamaguchi Shigehiro , Tamao Kohei 
Published: November 2004

Abstract
Various types of main group element-containing π-electron systems have been synthesized using silole, dibenzoborole, or bis-silicon-bridged stilbene as the key building units. In these π-electron systems, the orbital interaction between the main group element moiety and the π-conjugated framework, such as pπ–π* and σ*–π* conjugation, plays a crucial role in determining their characteristic electronic structures and makes them promising materials for applications in organic electronics and optoelectronics.
Preparation of Fast Proton-Conducting Zinc Metaphosphate Hydrogel and Its Potential Application to Electric Double-layer Capacitors
Authors: Daiko Yusuke , Akamatsu Takafumi , Kasuga Toshihiro , Nogami Masayuki 
Published: November 2004

Abstract
A novel highly viscous hydrogel electrolyte with high proton conductivity was prepared via hydration of zinc metaphosphate glass powders. The hydrogel showed a high electrical conductivity of ≈5 mS cm−1 at room temperature due to proton hopping between P–OH groups and water molecules. The hydrogel exhibited a low self-discharge rate. Chronoamperometric measurements indicated that the hydrogel has fast charge-discharge capability.
Monooxygen-containing Analogue of BDH-TTP, DHOT-TTP [2-(1,3-Dithiolan-2-ylidene)-5-(1,3-oxathiolan-2-ylidene)-1,3,4,6-tetrathiapentalene], and Its Metallic AuI2 Salt
Authors: Yamada Jun-ichi , Kunigita Ken-ichi , Akutsu Hiroki , Nakatsuji Shin’ichi , Kikuchi Koichi 
Published: November 2004

Abstract
The synthesis of DHOT-TTP, in which one sulfur atom of BDH-TTP [2,5-bis(1,3-dithiolan-2-ylidene)-1,3,4,6-tetrathiapentalene] is substituted by oxygen, has been accomplished. The DHOT-TTP donor possesses a less planar molecular structure than BDH-TTP, and gives a metallic AuI2 salt stable down to 1.4 K, the crystal structure of which is elucidated.
Mixed-Alkali Effect of Tracer Diffusion and Ionic Conduction in Na-Rb Borate Glasses as a Function of Total Alkali Content
Authors: Voss Stephan , Berkemeier Frank , Imre Árpád W. , Mehrer Helmut 
Published: November 2004

Abstract
The mixed-alkali effect is studied in Y [X Na2O · (1−X) Rb2O] · (1−Y) B2O3 glasses as a function of the total alkali content Y. To this aim the ionic transport in glasses with Y = 0.3 was investigated by impedance spectroscopy and by the radiotracer diffusion technique. The results are compared with data obtained earlier by our group on a glass system with Y = 0.2. In both systems the relative compositions X = Na/(Na + Rb) are varied from 0.0 to 1.0 in steps of 0.2. The dc electrical conductivity is higher in Y = 0.3 glasses than in Y = 0.2 glasses and exhibits a minimum in each system near X = 0.4. Also near X = 0.4 a pertaining maximum in activation enthalpy occurs being more pronounced for Y = 0.3 as compared to Y = 0.2. The glass-transition temperature T
g is almost identical for glasses with Y = 0.2 and 0.3 with a minimum near X = 0.2. The diffusivities of 22Na and 86Rb measured at a constant temperature (380 °C) show in both glass systems (Y = 0.3 and Y = 0.2) a similar dependence on the composition parameter X. The 86Rb diffusivity decreases exponentially with decreasing Rb content. The 22Na diffusivity decreases with decreasing Na content but reaches an almost constant plateau on the Rb-rich side. For each relative composition X the diffusivities of the two isotopes increase by nearly the same constant factor, when Y is increased from 0.2 to 0.3. In both systems 22Na- and 86Rb-diffusivities as functions of the composition parameter X intersect near X = 0.2 explaining the minimum in dc-conductivity. Composition dependent common Haven ratios were obtained by comparing the conductivity with the diffusion data.
The Gauss‐Seidel fast affine projection algorithm for multichannel active noise control and sound reproduction systems
Authors: Bouchard Martin , Albu Felix 
Published: November 2004

AbstractIn the field of adaptive filtering, the fast implementations of affine projection algorithms are known to provide a good tradeoff between convergence speed and computational complexity. Such algorithms have recently been published for multichannel active noise control systems. Previous work reported that these algorithms can outperform more complex recursive least‐squares algorithms when noisy plant models are used in active noise control systems. This paper proposes a new fast affine projection algorithm for multichannel active noise control or sound reproduction systems, based on the Gauss–Seidel solving scheme. The proposed algorithm has a lower complexity than the previously published algorithms, with the same convergence speed and the same good performance with noisy plant models, and a potential for better numerical stability. It provides the best performance/cost ratio. Details of the algorithm and its complexity are presented in the paper, with simulation results to validate its performance. Copyright © 2004 John Wiley & Sons, Ltd.
Small‐Molecule Screening and Profiling by Using Automated Microscopy
Authors: Mitchison Timothy J. 
Published: November 2004

AbstractAutomated fluorescence microscopy provides a powerful tool for analyzing the physiological state of single cells with high throughput and high information content. Here I discuss two types of experiments in which this technology was used to discover and characterize bioactive small molecules. In phenotypic‐screening experiments, the goal is to find “hits” with specific effects on cells by screening large libraries of small molecules. An example is screening for small molecules that perturb mitosis by novel mechanisms. In cytological‐profiling experiments, the goal is to characterize the bioactivity of a limited number of small molecules in considerable depth, and thus understand their mechanism and toxicities at the cellular level. I discuss an example in which 100 small molecules with known bioactivity were profiled by using multiple fluorescent probes, and clustered into mechanistic classes by automated statistical analysis.
Development of a sustainable liquid fuels infrastructure based on biomass
Authors: Towler Gavin P. , Oroskar Anil R. , Smith Suzanne E. 
Published: November 2004

AbstractRenewable energy sources are currently receiving much attention, both as a means of reducing the dependency of the United States on imported oil and as a long‐term substitute for fossil fuels. An important part of any renewable energy strategy is to find suitable transportation fuels to substitute for gasoline and diesel oil. Fuels derived from biomass can potentially meet this need; however, traditional routes to biomass fuels are inefficient, leading to low energy yields per acre and questionable sustainability.In this paper, we present a systemwide analysis of biomass fuels and their production infrastructure. By analyzing the relative efficiency of different farming, harvesting, and processing approaches, fuel compositions, and engine technologies, we can identify technologies that substantially improve the overall energy efficiency and sustainability of biomass fuels. The analysis helps identify areas where additional research would yield the greatest benefits and set cost targets that must be achieved for biomass fuels to become competitive with conventional energy sources. © 2004 American Institute of Chemical Engineers Environ Prog, 2004
Effective methods for scalable and continuous media streaming on peer‐to‐peer networks
Authors: Sasabe Masahiro , Wakamiya Naoki , Murata Masayuki , Miyahara Hideo 
Published: November 2004

AbstractWith the growth of computing power and the proliferation of broadband access to the internet, the use of media streaming has become widely diffused. By using the peer‐to‐peer (P2P) communication architecture, media streaming can be expected to smoothly react to changes in network conditions and user demands for media streams. In this paper, to achieve continuous and scalable media streaming, we introduce our scalable media search and in‐time retrieval methods. Through several simulation experiments, we show that our methods can accomplish continuous media play‐out for popular media streams without introducing extra load on the system. However, we also show that an LRU cache replacement algorithm cannot provide users with continuous media play‐out for unpopular media streams. To tackle this problem, we take inspiration from biological systems to propose a new cache replacement algorithm that considers the balance between supply and demand for media streams. We demonstrate that our proposed algorithm can improve the continuity of media play‐out compared with LRU. Furthermore, we find that the proposed algorithm can adapt to changes in the popularity of various media. Copyright © 2004 AEI
Efficient search in unstructured peer‐to‐peer networks
Authors: Cholvi Vicent , Felber Pascal , Biersack Ernst 
Published: November 2004

AbstractThe huge popularity of recent peer‐to‐peer (P2P) file sharing systems has been mainly driven by the scalability of their architectures and the flexibility of their search facilities. Such systems are usually designed as unstructured P2P networks, because they impose few constraints on topology and data placement and support highly versatile search mechanisms. A major limitation of unstructured P2P networks lies, however, in the inefficiency of their search algorithms, which are usually based on simple flooding schemes. In this paper, we propose novel mechanisms for improving search efficiency in unstructured P2P networks. Unlike other approaches, we do not rely on specialized search algorithms; instead, the peers perform local dynamic topology adaptations, based on the query traffic patterns, in order to spontaneously create communities of peers that share similar interests. The basic premise of such semantic communities is that file requests have a high probability of being fulfilled within the community they originate from, therefore increasing the search efficiency. We propose further extensions to balance the load among the peers and reduce the query traffic. Extensive simulations under realistic operating conditions substantiate that our techniques significantly improve the search efficiency and reduce the network load. Copyright © 2004 AEI
Characterization of soil moisture conditions at temporal scales from a few days to annual
Authors: Lauzon Nicolas , Anctil François , Petrinovic Juan 
Published: November 2004

AbstractThis work proposes the analysis of soil moisture conditions based on the use of two recently developed descriptive techniques: (1) wavelet analysis and (2) self‐organizing mapping through Kohonen neural networks. This analysis is applied to soil moisture profiles as well as supporting data, i.e. precipitation, temperature and flow observations, from an experimental site in the Orgeval watershed in France. With wavelet analysis and self‐organizing mapping, a comprehensive description of the structure of soil moisture profile, its evolution over time, and how it relates to observations of precipitation, temperature and flow can be obtained. Soil moisture conditions, particularly in the Orgeval watershed, are an important feature of the hydrologic cycle. There might be a significant advantage to consider soil moisture information in a variety of hydrologic models, such as streamflow models often employed in simulation and prediction modes for operational purposes, and the analysis performed here provides some avenues leading to the consideration of this information. Copyright © 2004 John Wiley & Sons, Ltd.
Variations in dissolved CO2 and CH4 in a first‐order stream and catchment: an investigation of soil–stream linkages
Authors: Hope Diane , Palmer Sheila M. , Billett Michael F. , Dawson Julian J. C. 
Published: November 2004

AbstractSpatial and seasonal variations in CO2 and CH4 concentrations in streamwater and adjacent soils were studied at three sites on Brocky Burn, a headwater stream draining a peatland catchment in upland Britain. Concentrations of both gases in the soil atmosphere were significantly higher in peat and riparian soils than in mineral soils. Peat and riparian soil CO2 concentrations varied seasonally, showing a positive correlation with air and soil temperature. Streamwater CO2 concentrations at the upper sampling site, which mostly drained deep peats, varied from 2·8 to 9·8 mg l−1 (2·5 to 11·9 times atmospheric saturation) and decreased markedly downstream. Temperature‐related seasonal variations in peat and riparian soil CO2 were reflected in the stream at the upper site, where 77% of biweekly variation was explained by an autoregressive model based on: (i) a negative log‐linear relationship with stream flow; (ii) a positive linear relationship with soil CO2 concentrations in the shallow riparian wells; and (iii) a negative linear relationship with soil CO2 concentrations in the shallow peat wells, with a significant 2‐week lag term. These relationships changed markedly downstream, with an apparent decrease in the soil–stream linkage and a switch to a positive relationship between stream flow and stream CO2. Streamwater CH4 concentrations also declined sharply downstream, but were much lower (<0·01 to 0·12 mg l−1) than those of CO2 and showed no seasonal variation, nor any relationship with soil atmospheric CH4 concentrations. However, stream CH4 was significantly correlated with stream flow at the upper site, which explained 57% of biweekly variations in dissolved concentrations. We conclude that stream CO2 can be a useful integrative measure of whole catchment respiration, but only at sites where the soil–stream linkage is strong. Copyright © 2004 John Wiley & Sons, Ltd.
Experimental evidence of fast groundwater responses in a hillslope/floodplain area in the Black Forest Mountains, Germany
Authors: Wenninger Jochen , Uhlenbrook Stefan , Tilch Nils , Leibundgut Christian 
Published: November 2004

AbstractAnalysis of water flow pathways from hillslopes to streams is essential for the optimal protection of water resources as well as for ecohydrological studies. This study addresses runoff generation processes at a hillslope and near‐stream shallow groundwater system in the Black Forest Mountains, southwestern Germany. The changing spatial and temporal flow patterns during differing hydrological situations were examined using a combined hydraulic and hydrochemical approach. Groundwater levels at 10 wells, discharge at a near‐stream saturated area, and several natural tracers (deuterium, dissolved silica, and major anions and cations) were observed at different locations during high and low flows. The importance of the groundwater component during flood formation was clearly demonstrated: its contribution was about 80% during a double peak flood event at the saturated area. In addition, a rapid change of the shallow groundwater levels was observed along two transects of groundwater wells in the floodplain. This led to an enhanced groundwater discharge into the saturated area located at the end of one study transect. The amount of groundwater additionally activated during the event was about 30% of total discharge recorded at the outlet of the saturated area. Two alternative hypotheses are discussed to explain this phenomenon: the establishment of locally confined conditions and the development of a pressure wave (hypothesis A), or the significant change of the three‐dimensional groundwater flow lines that caused a large increase of the groundwater catchment at the saturated area during the investigated event (hypothesis B). Even if the exact flow paths and mechanisms could not be clearly identified, the importance of rapid responding hillslope groundwater was undoubtedly demonstrated by a combination of tracer and hydrometric methods. Copyright © 2004 John Wiley & Sons, Ltd.
Development of the nervus terminalis: Origin and migration
Authors: Whitlock Kathleen E. 
Published: November 2004

AbstractThe origin of the nervus terminalis is one of the least well understood developmental events involved in generating the cranial ganglia of the forebrain in vertebrate animals. This cranial nerve forms at the formidable interface of the anteriormost limits of migrating cranial neural crest cells, the terminal end of the neural tube and the differentiating olfactory and adenohypophyseal placodes. The complex cellular interactions that give rise to the various structures associated with the sensory placode (olfactory) and endocrine placode (adenohypophysis) surround and engulf this enigmatic cranial nerve. The tortured history of nervus terminalis development (see von Bartheld, this issue, pages 13–24) reflects the lack of consensus on the origin (or origins), as well as the experimental difficulties in uncovering the origin, of the nervus terminalis. Recent technical advances have allowed us to make headway in understanding the origin(s) of this nerve. The emergence of the externally fertilized zebrafish embryo as a model system for developmental biology and genetics has shed new light on this century‐old problem. Coupled with new developmental models are techniques that allow us to trace lineage, visualize gene expression, and genetically ablate cells, adding to our experimental tools with which to follow up on studies provided by our scientific predecessors. Through these techniques, a picture is emerging in which the origin of at least a subset of the nervus terminalis cells lies in the cranial neural crest. In this review, the data surrounding this finding will be discussed in light of recent findings on neural crest and placode origins. Microsc. Res. Tech. 65:2–12, 2004. © 2004 Wiley‐Liss, Inc.
Cell proliferation dynamics and morphological differentiation during regeneration in Dorvillea bermudensis (Polychaeta, Dorvilleidae)
Authors: Paulus Tanja , Müller Monika C.M. 
Published: November 2004

AbstractAlthough some species of Annelida have an enormous capacity to regenerate, it is not yet known whether reestablishment of lost body parts is performed by stem cells, depends on preceding dedifferentiation of somatic cells, or is a combination of both. In order to clarify how, in the case of epimorphic regeneration, the blastemas are formed, we applied the thymidine analog 5′‐bromo‐2′‐deoxyuridine (BrdU) in the dorvilleid polychaete Dorvillea bermudensis to identify cells in the S‐phase of the cell cycle. Regeneration pulse‐chase experiments were carried out to determine onset and dynamics of the proliferation process, and BrdU pulse‐chase experiments were undertaken to follow cell fate. We found irregularly distributed S‐phase cells throughout the body of adult specimens. Subsequent to amputation, these cells do not migrate from the amputee towards the wound site, where proliferation activity was documented no earlier than 16 h after fragmentation. In the initial phase, the proliferation rate at the anterior end exceeds the rate at the posterior end. Observance of identity could be demonstrated for the ectoderm and can be assumed for the two other germ layers. The anterior blastema transforms into the head, while the posterior forms the pygidium and persists as a proliferation zone; four or numerous segments are formed by intercalation between the former anterior or posterior blastema and the amputee. © 2004 Wiley‐Liss, Inc.
The Clifford–Cauchy transform with a continuous density: N. Davydov's theorem
Authors: Abreu‐Blaya Ricardo , Bory‐Reyes Juan , Gerus Oleg F. , Shapiro Michael 
Published: November 2004

AbstractN. A. Davydov was among the first mathematicians who investigated the question of the continuity of the complex Cauchy transform along a non‐smooth curve. In particular he proved that the Cauchy transform over an arbitrary closed, rectifiable Jordan curve can be continuously extended up to this curve from both sides if its density belongs to the Lipschitz class. In this paper we deal with higher dimensional analogue of Davydov's theorem within the framework of Clifford analysis. Copyright © 2005 John Wiley & Sons, Ltd.