82 research outputs found
A study analysis of cable-body systems totally immersed in a fluid stream
A general stability analysis of a cable-body system immersed in a fluid stream is presented. The analytical portion of this analysis treats the system as being essentially a cable problem, with the body dynamics giving the end conditions. The mathematical form of the analysis consists of partial differential wave equations, with the end and auxiliary conditions being determined from the body equations of motion. The equations uncouple to give a lateral problem and a longitudinal problem as in first order airplane dynamics. A series of tests on a tethered wind tunnel model provide a comparison of the theory with experiment
Evaluation of a Water Channel-Based Platform for Characterizing Aerostat Flight Dynamics: A Case Study on a Lighter-Than-Air Wind Energy System
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140442/1/6.2014-2711.pd
Expression of osterix Is Regulated by FGF and Wnt/β-Catenin Signalling during Osteoblast Differentiation
Osteoblast differentiation from mesenchymal cells is regulated by multiple signalling pathways.
Here we have analysed the roles of Fibroblast Growth Factor (FGF) and canonical
Wingless-type MMTV integration site (Wnt/β-Catenin) signalling pathways on zebrafish
osteogenesis. We have used transgenic and chemical interference approaches to manipulate
these pathways and have found that both pathways are required for osteoblast differentiation
in vivo. Our analysis of bone markers suggests that these pathways act at the same
stage of differentiation to initiate expression of the osteoblast master regulatory gene osterix
(osx). We use two independent approaches that suggest that osx is a direct target of these
pathways. Firstly, we manipulate signalling and show that osx gene expression responds
with similar kinetics to that of known transcriptional targets of the FGF and Wnt pathways.
Secondly, we have performed ChIP with transcription factors for both pathways and our
data suggest that a genomic region in the first intron of osx mediates transcriptional activation.
Based upon these data, we propose that FGF and Wnt/β-Catenin pathways act in part
by directing transcription of osx to promote osteoblast differentiation at sites of bone
formation
Mouse anatomy ontologies:enhancements and tools for exploring and integrating biomedical data
Mouse anatomy ontologies provide standard nomenclature for describing normal and mutant mouse anatomy, and are essential for the description and integration of data directly related to anatomy such as gene expression patterns. Building on our previous work on anatomical ontologies for the embryonic and adult mouse, we have recently developed a new and substantially revised anatomical ontology covering all life stages of the mouse. Anatomical terms are organized in complex hierarchies enabling multiple relationships between terms. Tissue classification as well as partonomic, developmental, and other types of relationships can be represented. Hierarchies for specific developmental stages can also be derived. The ontology forms the core of the eMouse Atlas Project (EMAP) and is used extensively for annotating and integrating gene expression patterns and other data by the Gene Expression Database (GXD), the eMouse Atlas of Gene Expression (EMAGE) and other database resources. Here we illustrate the evolution of the developmental and adult mouse anatomical ontologies toward one combined system. We report on recent ontology enhancements, describe the current status, and discuss future plans for mouse anatomy ontology development and application in integrating data resources. Mamm Genome 2015 Oct; 26(9-10):422-3
Mutations in fam20b and xylt1 Reveal That Cartilage Matrix Controls Timing of Endochondral Ossification by Inhibiting Chondrocyte Maturation
Differentiating cells interact with their extracellular environment over time. Chondrocytes embed themselves in a proteoglycan (PG)-rich matrix, then undergo a developmental transition, termed “maturation,” when they express ihh to induce bone in the overlying tissue, the perichondrium. Here, we ask whether PGs regulate interactions between chondrocytes and perichondrium, using zebrafish mutants to reveal that cartilage PGs inhibit chondrocyte maturation, which ultimately dictates the timing of perichondral bone development. In a mutagenesis screen, we isolated a class of mutants with decreased cartilage matrix and increased perichondral bone. Positional cloning identified lesions in two genes, fam20b and xylosyltransferase1 (xylt1), both of which encode PG synthesis enzymes. Mutants failed to produce wild-type levels of chondroitin sulfate PGs, which are normally abundant in cartilage matrix, and initiated perichondral bone formation earlier than their wild-type siblings. Primary chondrocyte defects might induce the bone phenotype secondarily, because mutant chondrocytes precociously initiated maturation, showing increased and early expression of such markers as runx2b, collagen type 10a1, and ihh co-orthologs, and ihha mutation suppressed early perichondral bone in PG mutants. Ultrastructural analyses demonstrated aberrant matrix organization and also early cellular features of chondrocyte hypertrophy in mutants. Refining previous in vitro reports, which demonstrated that fam20b and xylt1 were involved in PG synthesis, our in vivo analyses reveal that these genes function in cartilage matrix production and ultimately regulate the timing of skeletal development
American Radical Economists in Mao’s China: From Hopes to Disillusionment
American radical economists in the 1960s perceived China under Maoism as an important experiment in creating a new society, aspects of which they hoped could serve as a model for the developing world. But the knowledge of ‘actually existing Maoism’ was very limited due to the mutual isolation between China and the US. This paper analyses the First Friendship Delegation of American Radical Political Economists (FFDARPE) to the People’s Republic of China in 1972, consisting mainly of Union for Radical Political Economics (URPE) members, which was the first visit of a group of American economists to China since 1949. Based on interviews with trip participants as well as archival and published material, this paper studies what we can learn about the engagement with Maoism by American radical economists from their dialogues with Chinese hosts, from their on-the-ground observations, and their reflection upon return. We show how the visitors’ own ideas conflicted and intersected with their perception of the Maoist practice on gender relations; workers’ management and life in the communes. We also shed light on the diverging conceptions of the role for economic expertise between URPE and late Maoism. As the first in-depth study on the FFDARPE we provide rich empirical insights into an ice-breaking event in the larger process of normalization in the Sino-U.S relations, that ultimately led to the disillusionment of the Left with China
Optimised isolation method for RNA extraction suitable for RNA sequencing from feline teeth collected in a clinical setting and at post mortem
Biophysical stimuli induced by passive movements compensate for lack of skeletal muscle during embryonic skeletogenesis
An Analytical Investigation of Airship Survivability in Atmospheric Turbulence.
NRC publication: Ye
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