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There is a new perspective of a continuum of prediction problems, with a blurring of the distinction between short-term predictions and long-term climate projections. At the heart of this new perspective is the realization that all climate system predictions, regardless of time scale, share common processes and mechanisms; moreover, interactions across time and space scales are fundamental to the climate system itself. Further, just as seasonal-to-interannual predictions start from an estimate of the state of the climate system, there is a growing realization that decadal and longer-term climate predictions could be initialized with estimates of the current observed state of the atmosphere, oceans, cryosphere, and land surface. Even though the prediction problem itself is seamless, the best practical approach to it may be described as unified: models aimed at different time scales and phenomena may have large commonality but place emphasis on different aspects of the system. The potential benefits of this commonality are significant and include improved predictions on all time scales and stronger collaboration and shared knowledge, infrastructure, and technical capabilities among those in the weather and climate prediction communities. DOI: 10.1175/2009BAMS2752.1

Byline: Peter Caldwell (1), Hung-Neng S. Chin (1), David C. Bader (1), Govindasamy Bala (1,2) Abstract: This paper presents results from a 40 year Weather Research and Forecasting (WRF) based dynamical downscaling experiment performed at 12 km horizontal grid spacing, centered on the state of California, and forced by a 1deg x 1.25deg finite-volume current-climate Community Climate System Model ver. 3 (CCSM3) simulation. In-depth comparisons between modeled and observed regional-average precipitation, 2 m temperature, and snowpack are performed. The regional model reproduces the spatial distribution of precipitation quite well, but substantially overestimates rainfall along windward slopes. This is due to strong overprediction of precipitation intensity precipitation frequency is actually underpredicted by the model. Moisture fluxes impinging on the coast seem to be well-represented over California, implying that precipitation bias is caused by processes internal to WRF. Positive-definite moisture advection and use of the Grell cumulus parameterization result in some decrease in precipitation bias, but other sources are needed to explain the full bias magnitude. Surface temperature is well simulated in all seasons except summer, when overly-dry soil moisture results in a several degree warm bias in both CCSM3 and WRF. Additionally, coastal temperatures appear to be too warm due to a coastal sea surface temperature bias inherited from CCSM3. Modeled snowfall/snowmelt agrees quite well with observations, but snow water equivalent is found to be much too low due to monthly reinitialization of all regional model fields from CCSM3 values. Author Affiliation: (1) Lawrence Livermore National Lab, L-103, P.O. Box 808, Livermore, CA, 94566, USA (2) Center for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bangalore, India Article History: Registration Date: 09/03/2009 Received Date: 07/05/2008 Accepted Date: 03/12/2008 Online Date: 08/05/2009

During mouse development, the sophisticated vascular network of the lung is established from embryonic day (E)[approximately equal to] 10.5 and continues to develop postnatally. This network is composed of endothelial cells enclosed by vascular smooth muscle, pericytes, and other mesenchymal cells. Recent in vivo lineage labeling studies in the developing heart and intestine suggest that some of the vascular smooth muscle cells arise from the surface mesothelium. In the developing lung, the Wilm's tumor 1 gene (Wt1) is expressed only in the mesothelial cells. Therefore, we lineage-labeled the mesothelium in vivo by using a Wt1-Cre transgene in combination with either Rosa26[R.sup.lacz], Rosa26[R.sup.CAG-hPLAP], of Rosa26[R.sup.EYFP] reporter alleles. In all three cases, cells derived from lineage-labeled mesothelium are found inside the lung and as smooth muscle actin (SMA) and PDGF receptor-beta positive cells in the walls of pulmonary blood vessels. To corroborate this finding, we used 5-(and6)-carboxy-2',7'-dichlorofluorescein diacetate, succinimidyl ester 'mixed isomers' (CCFSE) dye to label mesothelial cells on the surface of the embryonic lung. Over the course of 72-h culture, dye-labeled cells also appear within the lung mesenchyme. Together, our data provide evidence that mesothelial cells serve as a source of vascular smooth muscle cells in the developing lung and suggest that a conserved mechanism applies to the development of blood vessels in all coelomic organs. lineage tracing | blood vessell | embryo | pleura

A regeneration-theory approach is used to characterize the average overall completion time in a distributed systems in the presence of delays imposed by the communication medium. The performance of the dynamic load-balancing policy is compared with that of static policies as well as existing dynamic load-balancing policies.

Bves/pop1a is a unique, highly conserved integral membrane protein expressed in embryonic epithelia and striated muscle. Although studies have proposed a role in epithelial morphogenesis, the function of Bves/pop1a in development is completely unknown. Here we show that Xenopus laevis Bves (Xbves) RNA and protein are expressed in epithelia of the early embryon. Transfection of Xbves into nonadherent mouse L cells confers cell/cell adhesion. Global inhibition of Xbves function by morpholino injection into two-cell embryos arrests development at gastrulation by deregulating the epithelial movements of epiboly and involution. Clonal inhibition of Xbves activity within the A1 blastomere and its derivatives completely randomizes movement of its progeny within otherwise normally differentiating embryos. These data demostrate that Bves/pop1a proteins play a critical role in epithelial morphogenesis and, specifically, in the cell movements essential for epithelial rearrangements that occur during X. laevis development. cell adhesion | gastrulation | embryo | convergent extension morpholino

LIS1 and nuclear distribution gene E (NudE) are partner proteins in a conserved pathway regulating the function of dynein and microtubules. Here, we present data that cytoplasmic LEK1 (cytLEK1), a large protein containing a spectrin repeat and multiple leucine zippers, is a component of this pathway through its direct interaction with NudE, as determined by a yeast two-hybrid screen. We identified the binding domains in each molecule, and coimmuno-precipitation and colocalization studies confirmed the specificity of the interaction between cytLEK1 and NudE. Confocal deconvolution analysis revealed that cytLEK1 exhibits colocalization with endogenous NudE and with the known Nude binding partners, LIS1 and dynein. By localizing the NudE-binding domain of cytLEK1 to a small domain within the molecule, we were able to disrupt cytLEK1 function by using a dominant negative approach in addition to LEK1 knockdown and, thus, examine the role of the cytLEK1-NudE interaction in cells. Consistent with a defect in the LIS1 pathway, disruption of cytLEK1 function resulted in alteration of microtubule organization and cellular shape. The microtubule network of cells became tightly focused around the nucleus and resulted in a rounded cell shape. Additionally, cells exhibited a severe inability to repolymerize their microtubule networks after nocodazole challenge. Taken together, our studies revealed that cytLEK1 is essential for cellular functions regulated by the LIS1 pathway. cytoskeleton

In this brief, a generalized topology of block shift networks (BSNs), named generalized block shift network (GBSN), is proposed for interconnection networks in clusters. The BSNs possess many desirable topological features, such as flexibility in node degree, small diameter and average distance, and easy VLSI implementation. However, the regular structure of each block in the BSN is not suitable for the networks in clusters that usually have arbitrary number of nodes. The proposed GBSN offers a balance between regularity and irregularity of the interconnection networks for clusters. We also analyze the embedding of the BSN into the GBSN, and discuss the versatility of the GBSN in terms of slowdown factors compared to the BSN. Index Terms--Block shift network (BSN), general block shift network (GBSN), routing, slowdown factor.

This parallel algorithm is suitable for real time analysis and preparation of texture based on Markov and Gibbs random field models. The technique provides machine-independent scalable aglorithms for image processing. The method is tested on Thinking Machines CM-2 and CM-5. An irregular number of virtual processors are provided to react on large numbers of data in parallel.

The anterior lateral plate mesoderm has the capacity to form distinct cardiomyogenic cell lineages soon after gastrulation. A minimal defined culture system in vitro is adequate to maintain the lineages' positionally dependent maturation. Cardiogenic mesoderm and endoderm were removed from the chicken embryo at Hamburger and Hamilton stages 4-8 to determine whether undifferentiated cardiogenic tissue could diversify into distinct anterior and posterior lineages before the heart was formed.

A study of the cellular sources of heart cells using the QCE-6 cell line isolated from a differentiating cardiomyogenic cell from avian cardiogenic mesoderm reveals that retinoic acid and growth factors added to the culture medium activate the expression of cardiac myogenic and endothelial cell phenotypes by QCE-6 cells at high frequency. Several cardiac- and muscle-specific proteins are expressed by the activated cardiomyogenic cells. Differentiation of QCE-6 cells is similar to the formation of an initially differentiated precontractile cardiac myocyte from cardiogenic mesoderm.

Analysis of cardiac myocyte progenitors' commitment during gastrulation reveals that pregastrulated cells undergo restricted cardiac myocyte differentiation and that postgastrulated anterior lateral-plate mesoderm consists of committed cardiac progenitors with unequal differentiating capability. Bromodeoxyuridine (BrdU) fully inhibits the progenitor cell differentiation from the 4th and 5th stages but not from stages 7 and 8. The progenitors acquire BrdU resistance during their migration and postgastrulation.

Indirect histochemical analysis of an embryotic heart revealed the presence of DNA-binding proteins found exclusively in the nucleus of cardiac cells. Samples from different stages of development were immunoprecipitated and incubated to test for the presence and characteristics of the proteins. Data indicated that at least one protein occurs transiently through the various stages of heart cell development. Furthermore, this protein reacts with MyoD1 and myogenin.

Clinical Nuclear Cardiology: State of the Art and Future Directions, Third Edition. By Barry Zaret Elsevier, 2004 Sometimes you can judge a book by its cover. The third edition of [...]

We have used a subtractive method to clone novel messages enriched in the heart. Here we show that one such message, byes (blood vessel/epicardial substance) is a novel protein that is highly conserved between chicken and mouse. The byes message is detected at high levels in early chick hearts. Using anti-Byes antibodies, we show expression in cells of the proepicardial organ, migrating epicardium, epicardial-derived mesenchyme, and smooth muscle of the developing intracardiac arterial system, including the coronary arteries. Our data suggest that Bves is an early marker of developing vascular smooth muscle cells. In addition, the expression pattern of Bves protein reveals the patterning of intracardiac vascular smooth muscle and possible insights into the cellular regulation of smooth muscle differentiation during vasculogenesis.