bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integration of declarative and constraint programming
Authors: HOFSTEDT PETRA , PEPPER PETER 
Published: February 2007

AbstractCombining a set of existing constraint solvers into an integrated system of cooperating solvers is a useful and economic principle to solve hybrid constraint problems. In this paper we show that this approach can also be used to integrate different language paradigms into a unified framework. Furthermore, we study the syntactic, semantic and operational impacts of this idea for the amalgamation of declarative and constraint programming.
Combining relational algebra, SQL, constraint modelling, and local search
Authors: CADOLI MARCO , MANCINI TONI 
Published: February 2007

AbstractThe goal of this paper is to provide a strong integration between constraint modelling and relational DBMSs. To this end we propose extensions of standard query languages such as relational algebra and SQL, by adding constraint modelling capabilities to them. In particular, we propose non-deterministic extensions of both languages, which are specially suited for combinatorial problems. Non-determinism is introduced by means of a guessing operator, which declares a set of relations to have an arbitrary extension. This new operator results in languages with higher expressive power, able to express all problems in the complexity class NP. Some syntactical restrictions which make data complexity polynomial are shown. The effectiveness of both extensions is demonstrated by means of several examples. The current implementation, written in Java using local search techniques, is described.
Forward slicing of functional logic programs by partial evaluation
Authors: SILVA JOSEP , VIDAL GERMÁN 
Published: February 2007

AbstractProgram slicing has been mainly studied in the context of imperative languages, where it has been applied to a wide variety of software engineering tasks, like program understanding, maintenance, debugging, testing, code reuse, etc. This work introduces the first forward slicing technique for declarative multi-paradigm programs which integrate features from functional and logic programming. Basically, given a program and aslicing criterion(a function call in our setting), the computed forward slice contains those parts of the original program which arereachablefrom the slicing criterion. Our approach to program slicing is based on an extension of (online) partial evaluation. Therefore, it provides a simple way to develop program slicing tools from existing partial evaluators and helps to clarify the relation between both methodologies. A slicing tool for the multi-paradigm language Curry, which demonstrates the usefulness of our approach, has been implemented in Curry itself.
Striving for normality: whole body regeneration through a series of abnormal generations
Authors: Voskoboynik Ayelet , Simon-Blecher Noa , Soen Yoav , Rinkevich Baruch , De Tomaso Anthony W. , Ishizuka Katherine J. , Weissman Irving L. 
Published: February 2007

ABSTRACTEmbryogenesis and asexual reproduction are commonly considered to be coordinated developmental processes, which depend on accurate progression through a defined sequence of developmental stages. Here we report a peculiar developmental scenario in a simple chordate, Botryllus schlossenri, wherein a normal colony of individuals (zooids and buds) is regenerated from the vasculature (vascular budding) through a sequence of morphologically abnormal developmental stages. Vascular budding was induced by surgically removing buds and zooids from B. schlossenri colonies, leaving only the vasculature and the tunic that connects them. In vivo imaging and histological sections showed that the timing and morphology of developing structures during vascular budding deviated significantly from other asexual reproduction modes (the regular asexual reproduction mode in this organism and vascular budding in other botryllid species). Subsequent asexual reproduction cycles exhibited gradual regaining of normal developmental patterns, eventually leading to regeneration of a normal colony. The conversion into a normal body form suggests the activation of an alternative pathway of asexual reproduction, which involves gradual regaining of normal positional information. It presents a powerful model for studying the specification of the same body plan by different developmental programs.—Voskoboynik A., Simon‐Blecher, N., Soen, Y., Rinkevich, B., De Tomaso A. W., Ishizuka, K. J., Weissman I. L., Striving for normality: whole body regeneration through a series of abnormal generations. FASEB J. 21, 1335–1344 (2007)
Mechanism of Cav1.2 channel modulation by the amino terminus of cardiac β2‐subunits
Authors: Herzig Stefan , Khan Ismail F. Y. , Gründemann Dirk , Matthes Jan , Ludwig Andreas , Michels Guido , Hoppe Uta C. , Chaudhuri Dipayan , Schwartz Arnold , Yue David T. , Hullin Roger 
Published: February 2007

ABSTRACTL‐type calcium channels are composed of a pore, α1c (CaV1.2), and accessory β‐ and α2δ‐subunits. The β‐subunit core structure was recently resolved at high resolution, providing important information on many functional aspects of channel modulation. In this study we reveal differential novel effects of five ß2‐subunits isoforms expressed in human heart ( β 2a‐e) on the single L‐type calcium channel current. These splice variants differ only by amino‐terminal length and amino acid composition. Single‐channel modulation by β2‐subunit isoforms was investigated in HEK293 cells expressing the recombinant L‐type ion conducting pore. All β2‐subunits increased open probability, availability, and peak current with a highly consistent rank order (ß2a≈ ß2b>ß2e≈ ß2c>ß2d). We show graded modulation of some transition rates within and between deep‐closed and inactivated states. The extent of modulation correlates strongly with the length of amino‐terminal domains. Two mutant ß2‐subunits that imitate the natural span related to length confirm this conclusion. The data show that the length of amino termini is a relevant physiological mechanism for channel closure and inactivation, and that natural alternative splicing exploits this principle for modulation of the gating properties of calcium channels.—Herzig, S., Khan, I. F. Y., Gründemarin, D., Matthes, J., Ludwig, A., Michels, G., Hoppe, U. C., Chaudhuri, D., Schwartz, A., Yue, D. T., Hullin, R. Mechanism of Cav1.2 channel modulation by the amino terminus of cardiac ß2‐sub‐units. FASEB J. 21, 1527–1538 (2007)
Multiquadric
Collocation Method for Time-Dependent Heat Conduction Problems With Temperature-Dependent Thermal
Properties
Authors: Chantasiriwan Somchart 
Published: February 2007

Abstract
The multiquadric collocation method is a meshless method that uses multiquadrics as its basis function. Problems of nonlinear time-dependent heat conduction in materials having temperature-dependent thermal properties are solved by using this method and the Kirchhoff transformation. Variable transformation is simplified by assuming that thermal properties are piecewise linear functions of temperature. The resulting nonlinear equation is solved by an iterative scheme. The multiquadric collocation method is tested by a heat conduction problem for which the exact solution is known. Results indicate satisfactory performance of the method.
Enhancement
of Convective Heat and Mass Transfer From Two Bubbles at High Reynolds
Number
Authors: Kendoush Abdullah
Abbas 
Published: February 2007

Abstract
Analytical solutions to the heat convection from two bubbles were obtained. These solutions were applied to the two bubbles with the flow along their line of centers and perpendicular to their line of centers. The method of images has been used to give a solution to the velocity distribution around the two bubbles. The derived solutions apply to fluid spheres. In general the derived solutions were compared well with the other available analytical and numerical results. Some avenues for further research were pointed out.
Proteomic and Microarray Analyses of theDictyosteliumZak1-GSK-3 Signaling Pathway Reveal a Role in Early Development
Authors: Strmecki Lana , Bloomfield Gareth , Araki Tsuyoshi , Dalton Emma , Skelton Jason , Schilde Christina , Harwood Adrian , Williams Jeffrey G. , Ivens Al , Pears Catherine 
Published: February 2007

ABSTRACTGskA, theDictyosteliumGSK-3 orthologue, is modified and activated by the dual-specificity tyrosine kinase Zak1, and the two kinases form part of a signaling pathway that responds to extracellular cyclic AMP. We identify potential cellular effectors for the two kinases by analyzing the corresponding null mutants. There are proteins and mRNAs that are altered in abundance in only one or the other of the two mutants, indicating that each kinase has some unique functions. However, proteomic and microarray analyses identified a number of proteins and genes, respectively, that are similarly misregulated in both mutant strains. The positive correlation between the array data and the proteomic data is consistent with the Zak1-GskA signaling pathway's functioning by directly or indirectly regulating gene expression. The discoidin 1 genes are positively regulated by the pathway, while the abundance of the H5 protein is negatively regulated. Two of the targets, H5 and discoidin 1, are well-characterized markers for early development, indicating that the Zak1-GskA pathway plays a role in development earlier than previously observed.
Reliability of MRI assessment of supraspinatus tendinopathy
Authors: Sein Mya Lay , Walton Judie , Linklater James , Harris Craig , Dugal Tej , Appleyard Richard , Kirkbride Brent , Kuah Donald , Murrell George A C 
Published: February 2007

Objective:To determine the interobserver and intraobserver reliability of the interpretation of MRIs for supraspinatus tendinosis.Methods:In the interobserver trial, the MRIs of 52 athletes’ shoulders were observed by 3 observers on one occasion within a 2-month period. All 52 images were read by the most experienced musculoskeletal radiologist on 3 different occasions on separate days without access to the previous readings for the intraobserver trial. Supraspinatus tendinosis was graded using a modified 4-point scale from grades 0 to grade 3.Results:The grading of MRI-determined supraspinatus tendinosis was reliable, having an intraclass correlation (ICC) of 0.85 when assessed by the single well-trained observer. Interobserver reliability was only fair to good (ICC = 0.55).Conclusions:Supraspinatus tendinosis can be accurately identified on MRI with little variation by a single well-trained observer. Interobserver reliability was only fair to good. Our data indicated that the reliability of the assessment was much greater in more experienced radiologists than in those with less experience.
Recent Climate-Driven Increases in Vegetation Productivity for the Western Arctic: Evidence of an Acceleration of the Northern Terrestrial Carbon Cycle
Authors: Kimball J. S. , Zhao M. , McGuire A. D. , Heinsch F. A. , Clein J. , Calef M. , Jolly W. M. , Kang S. , Euskirchen S. E. , McDonald K. C. , Running S. W. 
Published: February 2007

Abstract
Northern ecosystems contain much of the global reservoir of terrestrial carbon that is potentially reactive in the context of near-term climate change. Annual variability and recent trends in vegetation productivity across Alaska and northwest Canada were assessed using a satellite remote sensing–based production efficiency model and prognostic simulations of the terrestrial carbon cycle from the Terrestrial Ecosystem Model (TEM) and BIOME–BGC (BioGeoChemical Cycles) model. Evidence of a small, but widespread, positive trend in vegetation gross and net primary production (GPP and NPP) is found for the region from 1982 to 2000, coinciding with summer warming of more than 1.8°C and subsequent relaxation of cold temperature constraints to plant growth. Prognostic model simulation results were generally consistent with the remote sensing record and also indicated that an increase in soil decomposition and plant-available nitrogen with regional warming was partially responsible for the positive productivity response. Despite a positive trend in litter inputs to the soil organic carbon pool, the model results showed evidence of a decline in less labile soil organic carbon, which represents approximately 75% of total carbon storage for the region. These results indicate that the regional carbon cycle may accelerate under a warming climate by increasing the fraction of total carbon storage in vegetation biomass and more rapid turnover of the terrestrial carbon reservoir.
A New Look at Stratospheric Sudden Warmings. Part II: Evaluation of Numerical Model Simulations
Authors: Charlton Andrew J. , Polvani Lorenzo M. , Perlwitz Judith , Sassi Fabrizio , Manzini Elisa , Shibata Kiyotaka , Pawson Steven , Nielsen J. Eric , Rind David 
Published: February 2007

Abstract
The simulation of major midwinter stratospheric sudden warmings (SSWs) in six stratosphere-resolving general circulation models (GCMs) is examined. The GCMs are compared to a new climatology of SSWs, based on the dynamical characteristics of the events. First, the number, type, and temporal distribution of SSW events are evaluated. Most of the models show a lower frequency of SSW events than the climatology, which has a mean frequency of 6.0 SSWs per decade. Statistical tests show that three of the six models produce significantly fewer SSWs than the climatology, between 1.0 and 2.6 SSWs per decade. Second, four process-based diagnostics are calculated for all of the SSW events in each model. It is found that SSWs in the GCMs compare favorably with dynamical benchmarks for SSW established in the first part of the study.
These results indicate that GCMs are capable of quite accurately simulating the dynamics required to produce SSWs, but with lower frequency than the climatology. Further dynamical diagnostics hint that, in at least one case, this is due to a lack of meridional heat flux in the lower stratosphere. Even though the SSWs simulated by most GCMs are dynamically realistic when compared to the NCEP–NCAR reanalysis, the reasons for the relative paucity of SSWs in GCMs remains an important and open question.
A New Look at Stratospheric Sudden Warmings. Part I: Climatology and Modeling Benchmarks
Authors: Charlton Andrew J. , Polvani Lorenzo M. 
Published: February 2007

Abstract
Stratospheric sudden warmings are the clearest and strongest manifestation of dynamical coupling in the stratosphere–troposphere system. While many sudden warmings have been individually documented in the literature, this study aims at constructing a comprehensive climatology: all major midwinter warming events are identified and classified, in both the NCEP–NCAR and 40-yr ECMWF Re-Analysis (ERA-40) datasets. To accomplish this a new, objective identification algorithm is developed. This algorithm identifies sudden warmings based on the zonal mean zonal wind at 60°N and 10 hPa, and classifies them into events that do and do not split the stratospheric polar vortex.
Major midwinter stratospheric sudden warmings are found to occur with a frequency of approximately six events per decade, and 46% of warming events lead to a splitting of the stratospheric polar vortex. The dynamics of vortex splitting events is contrasted to that of events where the vortex is merely displaced off the pole. In the stratosphere, the two types of events are found to be dynamically distinct: vortex splitting events occur after a clear preconditioning of the polar vortex, and their influence on middle-stratospheric temperatures lasts for up to 20 days longer than vortex displacement events. In contrast, the influence of sudden warmings on the tropospheric state is found to be largely insensitive to the event type.
Finally, a table of dynamical benchmarks for major stratospheric sudden warming events is compiled. These benchmarks are used in a companion study to evaluate current numerical model simulations of the stratosphere.
Ten Years of Measurements of Tropical Upper-Tropospheric Water Vapor by MOZAIC. Part I: Climatology, Variability, Transport, and Relation to Deep Convection
Authors: Luo Zhengzhao , Kley Dieter , Johnson Richard H. , Smit Herman 
Published: February 2007

Abstract
Ten years (1994–2004) of measurements of tropical upper-tropospheric water vapor (UTWV) by the Measurement of Ozone and Water Vapor by Airbus In-Service Aircraft (MOZAIC) are investigated over three regions—the tropical Atlantic, tropical Africa, and the Asian monsoon region—to determine the UTWV climatology and variability on multiple scales and to understand them in relation to moisture transport and deep convection.
The seasonal migration of upper-tropospheric humidity (UTH) keeps pace with that of the ITCZ, indicating the convective influence on UTH distribution. Some significant regional differences are identified with the tropical Africa and the Asian monsoon regions being moister than the tropical Atlantic. UTH generally increases with height by 10%–20% relative humidity with respect to ice (RHi) from about 300 to 200 hPa, and the differences are larger in the deep Tropics than in the subtropics. The probability density functions of tropical UTH are often bimodal. The two modes stay rather constant; differences in the mean value are largely due to the variations in the proportion of the two modes as opposed to changes in the modes themselves. In the deep Tropics, the moisture level frequently reaches ice supersaturation, the most notable case being the near-equatorial Asian monsoon region during the wet season when ice supersaturation is observed 46% of the time.
Interannual variations are observed in association with the 1997–98 ENSO event. A warming of about 1–2 K is observed for all three regions equatorward of roughly 15°. Specific humidity also increases somewhat for the tropical Atlantic and tropical Africa, but the increase in temperature outweighs the increase in specific humidity such that RH decreases by 5%–15% RHi. In addition to the ENSO-related variation, MOZAIC also sees increases in both RH and specific humidity over tropical Africa from 2000 onward.
Moisture fluxes are computed from MOZAIC data and decomposed into contributions from the mean circulation and from eddies. The flux divergence, which represents the moisture source/sink from horizontal transport, is also estimated. Finally, the MOZAIC climatology and variability are revisited in relation to deep convection obtained from the International Satellite Cloud Climatology Project (ISCCP).
Detection of Human Influence on a New, Validated 1500-Year Temperature Reconstruction
Authors: Hegerl Gabriele C. , Crowley Thomas J. , Allen Myles , Hyde William T. , Pollack Henry N. , Smerdon Jason , Zorita Eduardo 
Published: February 2007

Abstract
Climate records over the last millennium place the twentieth-century warming in a longer historical context. Reconstructions of millennial temperatures show a wide range of variability, raising questions about the reliability of currently available reconstruction techniques and the uniqueness of late-twentieth-century warming. A calibration method is suggested that avoids the loss of low-frequency variance. A new reconstruction using this method shows substantial variability over the last 1500 yr. This record is consistent with independent temperature change estimates from borehole geothermal records, compared over the same spatial and temporal domain. The record is also broadly consistent with other recent reconstructions that attempt to fully recover low-frequency climate variability in their central estimate.
High variability in reconstructions does not hamper the detection of greenhouse gas–induced climate change, since a substantial fraction of the variance in these reconstructions from the beginning of the analysis in the late thirteenth century to the end of the records can be attributed to external forcing. Results from a detection and attribution analysis show that greenhouse warming is detectable in all analyzed high-variance reconstructions (with the possible exception of one ending in 1925), and that about a third of the warming in the first half of the twentieth century can be attributed to anthropogenic greenhouse gas emissions. The estimated magnitude of the anthropogenic signal is consistent with most of the warming in the second half of the twentieth century being anthropogenic.
Dynamics of the West African Monsoon under Mid-Holocene Precessional Forcing: Regional Climate Model Simulations
Authors: Patricola C. M. , Cook K. H. 
Published: February 2007

Abstract
The African Humid Period (AHP), about 14 800 yr ago [14.8–5.5 ka (ka ≡ 1000 yr ago)], was a time of increased humidity over Africa. Paleoclimate evidence suggests that the West African summer monsoon was stronger and more extensive 6 ka than today, and that the Saharan Desert was green. Here, a regional climate model that produces an excellent simulation of today’s climate over northern Africa is used to study the dynamics of the monsoon 6 ka. Changes in insolation, atmospheric CO2, and vegetation are used to impose 6-ka conditions, and the role of each forcing is isolated. Vegetation is not interactive, and the large-scale circulation and SSTs are fixed at present-day values for the 6-ka simulations.
The regional model produces precipitation increases across the Sahel and Sahara that are in good agreement with the paleodata. However, unobserved drying is simulated over the Guinean coast region where paleodata are sparse. Precipitation increases in the Sahel are related to a northward shift of the monsoon, the elimination of the African easterly jet, and an intensification and deepening of the low-level westerly jet on the west coast. The thermal low–Saharan high system of the present-day climate is replaced by a deep thermal low. When this system becomes fully developed in midsummer, cyclonic circulations transport moisture north into the Sahara, and rainfall increases there. Surface temperatures decrease despite the increased solar forcing 6 ka because of an increase in cloudiness. A moist static energy budget analysis shows that increased low-level moisture dominates the cooling to destabilize the vertical column and enhance convection. Even though solar forcing is the ultimate cause of the AHP, the model responds more strongly to the vegetation forcing, especially early in the summer season, emphasizing the importance of vegetation in maintaining the intensified monsoon system.
The Scripps Coupled Ocean–Atmosphere Regional (SCOAR) Model, with Applications in the Eastern Pacific Sector
Authors: Seo Hyodae , Miller Arthur J. , Roads John O. 
Published: February 2007

AbstractA regional coupled ocean–atmosphere model is introduced. It is designed to admit the air–sea feedbacks arising in the presence of an oceanic mesoscale eddy field. It consists of the Regional Ocean Modeling System (ROMS) and the Regional Spectral Model (RSM). Large-scale forcing is provided by NCEP/DOE reanalysis fields, which have physics consistent with the RSM. Coupling allows the sea surface temperature (SST) to influence the stability of the atmospheric boundary layer and, hence, the surface wind stress and heat flux fields. The system is denominated the Scripps Coupled Ocean–Atmosphere Regional (SCOAR) Model.The model is tested in three scenarios in the eastern Pacific Ocean sector: tropical instability waves of the eastern tropical Pacific, mesoscale eddies and fronts of the California Current System, and gap winds of the Central American coast. Recent observational evidence suggests air–sea interactions involving the oceanic mesoscale in these three regions. Evolving SST fronts are shown to drive an unambiguous response of the atmospheric boundary layer in the coupled model. This results in significant model anomalies of wind stress curl, wind stress divergence, surface heat flux, and precipitation that resemble the observations and substantiate the importance of ocean–atmosphere feedbacks involving the oceanic mesoscale.