Immunogenicity of formaldehyde and binary ethylenimine inactivated infectious bursal disease virus in broiler chicks   总被引：2，自引：2，他引：0  

Habib M  Hussain I  Irshad H  Yang ZZ  Shuai JB  Chen N 《Journal of Zhejiang University. Science. B》2006,7(8):660-664

Infectious bursal disease virus （IBDV） was inactivated by two different chemicals-formaldehyde and binary ethylenimine （BEI）. Formaldehyde was used at 0. 1% and 0.2%, while BEI was used at concentrations of 0.001 and 0.002 mol/L. These four vaccines were tested for their efficiency in generating humoral immune response in different groups of broiler chicks. Both BEI-inactivated vaccines gave relatively higher antibody titers and were almost twice as efficient as formaldehyde-inactivated ones.  相似文献   

Characterization and Classification of Mesenchymal Stem Cells in Several Species Using Surface Markers for Cell Therapy Purposes     

Hori Ghaneialvar  Leila Soltani  Hamid Reza Rahmani  Abbas Sahebghadam Lotfi  Masoud Soleimani 《Indian journal of clinical biochemistry : IJCB》2018,33(1):46-52

Mesenchymal stem cells are multipotent cells capable of replicating as undifferentiated cells, and have the potential of differentiating into mesenchymal tissue lineages such as osteocytes, adipocytes and chondrocytes. Such lineages can then be used in cell therapy. The aim of present study was to characterize bone marrow derived mesenchymal stem cells in four different species, including: sheep, goat, human and mouse. Human bone-marrow mesenchymal stem cells were purchased, those of sheep and goat were isolated from fetal bone marrow, and those of mouse were collected by washing bone cavity of femur and tibia with DMEM/F12. Using flow-cytometry, they were characterized by CD surface antigens. Furthermore, cells of third passage were examined for their osteogenic and adipogenic differentiation potential by oil red and alizarin red staining respectively. According to the results, CD markers studied in the four groups of mesenchymal stem cells showed a different expression. Goat and sheep expressed CD44 and CD166, and weakly expressed CD34, CD45, CD105 and CD90. Similarly, human and mouse mesenchymal cells expressed CD44, CD166, CD105 and CD90 whereas the expression of CD34 and CD45 was negative. In conclusion, although all mesenchymal stem cells display plastic adherence and tri-lineage differentiation, not all express the same panel of surface antigens described for human mesenchymal stem cells. Additional panel of CD markers are necessary to characterize regenerative potential and possible application of these stem cells in regenerative medicine and implantology.  相似文献   

Using Active Learning Methods to Strategically Select Essays for Automated Scoring     

Tahereh Firoozi  Hamid Mohammadi  Mark J. Gierl 《Educational Measurement》2023,42(1):34-43

Research on Automated Essay Scoring has become increasing important because it serves as a method for evaluating students’ written responses at scale. Scalable methods for scoring written responses are needed as students migrate to online learning environments resulting in the need to evaluate large numbers of written-response assessments. The purpose of this study is to describe and evaluate three active learning methods that can be used to minimize the number of essays that must be scored by human raters while still providing the data needed to train a modern Automated Essay Scoring system. The three active learning methods are the uncertainty-based, the topological-based, and the hybrid method. These three methods were used to select essays included in the Automated Student Assessment Prize competition that were then classified using a scoring model that was trained with the bidirectional encoder representations from a transformer language model. All three active learning methods produced strong results, with the topological-based method producing the most efficient classification. Growth rate accuracy was also evaluated. The active learning methods produced different levels of efficiency under different sample size allocations but, overall, all three methods were highly efficient and produced classifications that were similar to one another.  相似文献   

‘Cracks’ in the scholarly communications system: Insights from a longitudinal international study of early career researchers     

David Nicholas  Cherifa Boukacem-Zeghmouri  Blanca Rodríguez-Bravo  Eti Herman  Abdullah Abrizah  David Clark  Galina Serbina  David Sims  Marzena Świgoń  Jie Xu  Anthony Watkinson  Hamid R. Jamali  Carol Tenopir  Suzie Allard 《Learned Publishing》2023,36(2):319-322

• 170 early career researchers interviewed three times over 2 years, have uniquely contributed towards a stress test of scholarly communications and cracks have been identified.
• The perfect storm created by the convergence of millennial values and the pandemic appears to have fast-forwarded the cracking process, perhaps, for the good.
• The cracks in question are: (1) peer review; (2) reputational assessment; (3) unethical/questionable practices; (4) collaboration; (5) networking.

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