196,268 research outputs found
Overexpression of uvomorulin in a compaction-negative F9 mutant cell line.
No full textThe mutant F9 cell line F9att-5.51 synthesizes reduced amounts of uvomorulin (UM) protein and we hypothesized earlier (Adamson, Baribault, and Kemler, Dev. Biol. (1990), 138, 338) that this may account for its inability to compact into tightly aggregated balls of cells. Subsequently, when 5.51 cells are treated with retinoic acid to stimulate their differentiation, they are unable to form embryoid bodies as do wild-type cells which form an outer epithelial layer of visceral endoderm cells. We have now examined the possibility that the UM protein made in the mutant line is defective, but find that it is normal in structure and stability. The gene coding for UM appears to be normal as does the mRNA which is synthesized at a normal rate but is severely reduced in steady-state measurements of mutant cells. A rescue experiment was performed by increasing levels of UM in mutant cells by means of transfection with a UM expression vector. The resulting cells expressed abundant UM mRNA and protein but were still unable to form compacted aggregates and did not differentiate into embryoid bodies. Interestingly, the stability of endogenous UM mRNA was improved in the presence of exogenous UM; therefore, a positive feedback mechanism contributes to low mRNA levels in mutant cells. The accumulated data suggest that UM in 5.51 cells is unable to mount a compaction activity because a distal connecting link in the multicomponent process initiated by UM is missing or or aberrant. The missing component is likely to connect UM to actin and the cytoskeleton of the cell
FIGURES 8–11 in Anthracoidea obtusatae (Anthracoideaceae, Ustilaginales), a new smut fungus on Carex obtusata (Cyperaceae) from Central Asia
No full textFIGURES 8–11. Anthracoidea sp. on Carex obtusata from Canada (DAOM 28184). 8–9. Spores in LM. 10–11. Spores in SEM. Scale bars: 8–9 = 10 µm, 10–11 = 5 µm.Published as part of Denchev, Teodor T., Denchev, Cvetomir M., Begerow, Dominik & Kemler, Martin, 2023, Anthracoidea obtusatae (Anthracoideaceae, Ustilaginales), a new smut fungus on Carex obtusata (Cyperaceae) from Central Asia, pp. 139-148 in Phytotaxa 595 (2) on page 143, DOI: 10.11646/phytotaxa.595.2.2, http://zenodo.org/record/790583
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
An economic analysis of the demand for campsites from the Houston standard metropolitan statistical area
No full textβ-Catenin regulates excitatory postsynaptic strength at hippocampal synapses
No full textThe precise contribution of the cadherin–-catenin synapse adhe- sion complex in the functional and structural changes associated with the pre- and postsynaptic terminals remains unclear. Here we report a requirement for endogenous -catenin in regulating synaptic strength and dendritic spine morphology in cultured hippocampal pyramidal neurons. Ablating -catenin after the ini- tiation of synaptogenesis in the postsynaptic neuron reduces the amplitude of spontaneous excitatory synaptic responses without a concurrent change in their frequency and synapse density. The normal glutamatergic synaptic response is maintained by postsyn- aptic -catenin in a cadherin-dependent manner and requires the C-terminal PDZ-binding motif of -catenin but not the link to the actin cytoskeleton. In addition, ablating -catenin in postsynaptic neurons accompanies a block of bidirectional quantal scaling of glutamatergic responses induced by chronic activity manipulation. In older cultures at a time when neurons have abundant dendritic spines, neurons ablated for -catenin show thin, elongated spines and reduced proportion of mushroom spines without a change in spine density. Collectively, these findings suggest that the cad- herin–-catenin complex is an integral component of synaptic strength regulation and plays a basic role in coupling synapse function and spine morphology
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Serum estrone and estradiol from parturition to estrus and ovulation in suckled and nonsuckled primiparous Hereford heifers
No full textSerum concentration of estrone (E1) and estradiol (E2) were quantitated during the postpartum interval of suckled (S) and non-suckled (NS) primiparous heifers. Ovarian and uterine changes, estrus and ovulation were also recorded during this period. Then 2-year-olds primiparous Hereford heifers were randomly divided into two groups of five S and five NS animals. The calves of the NS group were removed at birth while those of the S groups were allowed to suckle four times daily until satiated. Blood samples were collected at 6-hour intervals from parturition to estrus, and observations for standing estrus conducted six times daily. The animals were palpated every other say and fed according to NRC recommendations. The nutritional status was monitored by recording individual animal weights at approximately 2-week intervals. The group means of each animal's prepartum and postpartum daily gain were within the recommendations reported necessary to avoid a delayed return to reproductive activity due to nutritional stress
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
Get PDFFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
- …
