Smad4 regulates growth plate matrix production and chondrocyte polarity.

Smad4 is an intracellular effector of the TGFβ family that has been implicated in Myhre syndrome, a skeletal dysplasia characterized by short stature, brachydactyly and stiff joints. The TGFβ pathway also plays a critical role in the development, organization and proliferation of the growth plate, although the exact mechanisms remain unclear. Skeletal phenotypes in Myhre syndrome overlap with processes regulated by the TGFβ pathway, including organization and proliferation of the growth plate and polarity of the chondrocyte. We used in vitro and in vivo models of Smad4 deficiency in chondrocytes to test the hypothesis that deregulated TGFβ signaling leads to aberrant extracellular matrix production and loss of chondrocyte polarity. Specifically, we evaluated growth plate chondrocyte polarity in tibiae of Col2-Cre+/-;Smad4fl/fl mice and in chondrocyte pellet cultures. In vitro and in vivo, Smad4 deficiency decreased aggrecan expression and increased MMP13 expression. Smad4 deficiency disrupted the balance of cartilage matrix synthesis and degradation, even though the sequential expression of growth plate chondrocyte markers was intact. Chondrocytes in Smad4-deficient growth plates also showed evidence of polarity defects, with impaired proliferation and ability to undergo the characteristic changes in shape, size and orientation as they differentiated from resting to hypertrophic chondrocytes. Therefore, we show that Smad4 controls chondrocyte proliferation, orientation, and hypertrophy and is important in regulating the extracellular matrix composition of the growth plate

Migrando do Parodox para o Interbase: a experiência do AINFO.

O objetivo do trabalho é relatar a experiência na migração do sistema de automação das bibliotecas da Embrapa - AINFO, em Paradox para o interbase, versào gratuita com código aberto, disponibilizado pela Borland Software Corporation em setembro de 2000. O método utilizado foi o de estudar a viabilidade, performance e aplicação de componentes de acesso nativo Interbase Ex´press (IBX) e Interbase Objects (IBO) que dispensam a Borland Database Engine (BDE) para conexão do sistema ao banco de dados.bitstream/CNPTIA/9205/1/RELATORIOTECNICO12int.pd

Effects of noise on hysteresis and resonance width in graphene and nanotubes resonators

We investigate the role that noise plays in the hysteretic dynamics of a suspended nanotube or a graphene sheet subject to an oscillating force. We find that not only the size but also the position of the hysteresis region in these systems can be controlled by noise. We also find that nano-resonators act as noise rectifiers: by increasing the noise in the setup, the resonance width of the characteristic peak in these systems is reduced and, as a result, the quality factor is increased.Comment: 15 pages, 6 figures. Sent to PRB (in revision

Regulation of Zn and Fe transporters by the GPC1 gene during early wheat monocarpic senescence

BACKGROUND: During wheat senescence, leaf components are degraded in a coordinated manner, releasing amino acids and micronutrients which are subsequently transported to the developing grain. We have previously shown that the simultaneous downregulation of Grain Protein Content (GPC) transcription factors, GPC1 and GPC2, greatly delays senescence and disrupts nutrient remobilization, and therefore provide a valuable entry point to identify genes involved in micronutrient transport to the wheat grain. RESULTS: We generated loss-of-function mutations for GPC1 and GPC2 in tetraploid wheat and showed in field trials that gpc1 mutants exhibit significant delays in senescence and reductions in grain Zn and Fe content, but that mutations in GPC2 had no significant effect on these traits. An RNA-seq study of these mutants at different time points showed a larger proportion of senescence-regulated genes among the GPC1 (64%) than among the GPC2 (37%) regulated genes. Combined, the two GPC genes regulate a subset (21.2%) of the senescence-regulated genes, 76.1% of which are upregulated at 12 days after anthesis, before the appearance of any visible signs of senescence. Taken together, these results demonstrate that GPC1 is a key regulator of nutrient remobilization which acts predominantly during the early stages of senescence. Genes upregulated at this stage include transporters from the ZIP and YSL gene families, which facilitate Zn and Fe export from the cytoplasm to the phloem, and genes involved in the biosynthesis of chelators that facilitate the phloem-based transport of these nutrients to the grains. CONCLUSIONS: This study provides an overview of the transport mechanisms activated in the wheat flag leaf during monocarpic senescence. It also identifies promising targets to improve nutrient remobilization to the wheat grain, which can help mitigate Zn and Fe deficiencies that afflict many regions of the developing world.Fil: Pearce, Stephen. University of California; Estados UnidosFil: Tabbita, Facundo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Cantu, Dario. University of California; Estados UnidosFil: Buffalo, Vince. University of California; Estados UnidosFil: Avni, Raz. Tel Aviv University; IsraelFil: Vazquez Gross, Hans. University of California; Estados UnidosFil: Zhao, Rongrong. China Agricultural University; ChinaFil: Conley, Christopher J.. University of California; Estados UnidosFil: Distelfeld, Assaf. Faculty Of Life Sciences, Department Of Molecular Biolo;Fil: Dubcovsky, Jorge. University of California; Estados Unidos. Howard Hughes Medical Institute ; Estados Unidos. Gordon & Betty Moore Foundation Investigator; Estados Unido

ThYme: a database for thioester-active enzymes

The ThYme (Thioester-active enzYme; http://www.enzyme.cbirc.iastate.edu) database has been constructed to bring together amino acid sequences and 3D (tertiary) structures of all the enzymes constituting the fatty acid synthesis and polyketide synthesis cycles. These enzymes are active on thioester-containing substrates, specifically those that are parts of the acyl-CoA synthase, acyl-CoA carboxylase, acyl transferase, ketoacyl synthase, ketoacyl reductase, hydroxyacyl dehydratase, enoyl reductase and thioesterase enzyme groups. These groups have been classified into families, members of which are similar in sequences, tertiary structures and catalytic mechanisms, implying common protein ancestry. ThYme is continually updated as sequences and tertiary structures become available

Evaluating team effectiveness: Examination of the TEAM Assessment Tool.

The present study evaluates the psychometric properties of the TEAM Assessment Tool. The assessment was developed to evaluate work team effectiveness as a basis for providing developmental feedback for work teams. The proposed TEAM Assessment Tool includes 12 dimensions of work team effectiveness with 90 items total. The dimension names are (a) Communication, (b) Decision-Making, (c) Performance, (d) Customer Focus, (e) Team Meetings, (f) Continuous Improvement, (g) Handling Conflict, (h) Leadership, (i) Empowerment, (j) Trust, (k) Cohesiveness/Team Relationships, and (l) Recognition and Rewards. Data were collected from employees of a large aerospace organization headquartered in the United States who are participating in work teams (N= 554). Factor analysis guided development of six new scales of team effectiveness as follows: (1) Teamwork, (2) Decision-Making, (3) Leadership Support, (4) Trust and Respect, (5) Recognition and Rewards, and (6) Customer Focus. Reliability of scales was demonstrated using Cronbach's coefficient alpha. Construct validity was demonstrated through subject matter expert (SME) input, exploratory factor analysis, and scale reliability analysis. Criterion validity was demonstrated by significant correlations at the p<.01 level comparing two measures of team member opinion of team performance and level of performance as indicated by the six subscale scores and overall scale scores of the final TEAM Assessment Tool

A Bayesian Reasoning Framework for On-Line Business Information Systems

We describe a Bayesian Reasoning Framework (BRF) that supports business rule operations for on-line information systems. BRF comprises a three-layer environment with business information systems at the top, a middle-ware Bayesian reasoning server, and a Bayesian reasoning engine at the bottom. The top and middle-ware layers communicate via SOAP/XML protocol, while the middle-ware and bottom layers communicate via a Tag-value protocol that fetches business rules from a central repository. BRF is built as a Bayesian Reasoning Agent and tested in a helpdesk system for assigning advisors to users for trouble-shooting in the operation of business information systems. BRF is modeled following a use-case methodology as well as an inference modeling that uses an assignation template from Common- KADS. The concept, design and implementation of BRF for real-world, on-line business information systems are the main contribution of this research project

An Initial Archaeological Assessment of John James Park, City of San Antonio, Texas

In January, 1977, the City of San Antonio Department of Parks and Recreation (Ronald L. Darner, Director) and the Center for Archaeological Research, The University of Texas at San Antonio (Thomas R. Hester, Director), entered into a contract for the archaeological assessment of John James Park. The park property (Fig. 1), is located just north of Fort Sam Houston, and the eastern boundary fronts on Salado Creek, a major tributary of the San Antonio River. The field survey was carried out under the general supervision of Dr. Thomas R. Hester and Mr. Jack D. Eaton, with the field crew consisting of Elizabeth Cantu Frkuska, Augustine J. Frkuska and Fred Valdez, Jr. The goal of this initial survey was to provide an assessment of archaeological or historical resources that might be present within the confines of the park, and, if such resources were found, to record and evaluate them