1,730 research outputs found

    Combined Nucleosynthetic Yields of Multiple First Stars

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    Modern numerical simulations of the formation of the first stars predict that the first stars formed in multiples. In those cases, the chemical yields of multiple supernova explosions may have contributed to the formation of a next generation star. We match the chemical abundances of the oldest observed stars in the universe to a database of theoretical supernova models, to show that it is likely that the first stars formed from the ashes of two or more progenitors.Comment: 3 pages, 2 figures, NIC 2016 Conference Proceeding

    Writing Business Plans for a Life Science Startup or Clinical Program

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    The business plan is an important tool for raising capital, finding strategic partners, recruit­ing, and providing an internal guide on how to drive a company’s growth. The plan should include an executive overview, introduction to the management team, market and competitive analyses, value proposition, operating plan, financial projections, and potential risks. The plan should be concise, well written, and dynamic. Details behind key assumptions should be included. Common business plan pitfalls include focusing only on the product without framing it in the context of the consumers/patients, the market dynamics, and the ecosystem in which it will be launched, as well as giving financials that are too aggressive and precise given the stage the company is in. New founders should consider engaging experts to help test assumptions as they develop the key parts of the business plan, including the financial projections. Many of the same concepts for writing a business plan for a startup apply to creating a business plan for a new clinical program or expanding operations within a health system

    Assessing scholarly communication programs

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    Do you have issues quantifying the success of your scholarly communication programs? Many CSUs not only struggle with how to properly fund and staff scholarly communication programs, but also how to show their value. Sacramento State and San Jose State received an IMLS National Forum grant in 2019 to determine how similar public institutions were assessing their scholarly communication programs. In our multi-phased grant project, we used the University of Central Florida’s Research Lifecycle (https://library.ucf.edu/about/departments/scholarly-communication/overview-research-lifecycle/ ) as a framing document for all the multi-faceted services that scholarly communication encompasses. Within this presentation, we will share an assessment rubric created to measure impact of services to preserve and disseminate research, including repository services. We hope to elicit feedback from the group and gauge interest in implementing similar rubrics at your campus

    Scholarly Communication Priorities Among M1 Institutions: A Mixed-Methods Study

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    This program presents the result of an IMLS-funded, mixed-methods study that investigated the scholarly communication programming and staffing priorities among M1 (Master\u27s Colleges and Universities – Larger programs) libraries. Using a complex research life cycle to frame discussion, twenty librarians from M1 institutions participated in focus groups and provided structured information on their libraries\u27 scholarly communication program, development, and staffing. Scholarly communication service and support among M1 institutions continue to grow and develop within the context of limited budgets and staffing. Audience participants will become acquainted with the prevalence of diverse scholarly communication programming and services and their assessment among a sampling of M1 institutions. Qualitativeanalysis of the focus group transcripts highlights the contexts, challenges, and future directions of scholarly communication programming and services among the M1 institutions

    Metal-Poor Stars Observed with the Magellan Telescope. III. New Extremely and Ultra Metal-Poor Stars from SDSS/SEGUE and Insights on the Formation of Ultra Metal-Poor Stars

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    We report the discovery of one extremely metal-poor (EMP; [Fe/H]<-3) and one ultra metal-poor (UMP; [Fe/H]<-4) star selected from the SDSS/SEGUE survey. These stars were identified as EMP candidates based on their medium-resolution (R~2,000) spectra, and were followed-up with high-resolution (R~35,000) spectroscopy with the Magellan-Clay Telescope. Their derived chemical abundances exhibit good agreement with those of stars with similar metallicities. We also provide new insights on the formation of the UMP stars, based on comparison with a new set of theoretical models of supernovae nucleosynthesis. The models were matched with 20 UMP stars found in the literature, together with one of the program stars (SDSS J1204+1201), with [Fe/H]=-4.34. From fitting their abundances, we find that the supernovae progenitors, for stars where carbon and nitrogen are measured, had masses ranging from 20.5 M_sun to 28 M_sun and explosion energies from 0.3 to 0.9x10^51 erg. These results are highly sensitive to the carbon and nitrogen abundance determinations, which is one of the main drivers for future high-resolution follow-up of UMP candidates. In addition, we are able to reproduce the different CNO abundance patterns found in UMP stars with a single progenitor type, by varying its mass and explosion energy.Comment: 15 pages, 12 figures; accepted for publication in Ap

    A comparison of 111In- or 64Cu-DOTA-trastuzumab Fab fragments for imaging subcutaneous HER2-positive tumor xenografts in athymic mice using microSPECT/CT or microPET/CT

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    Abstract Background Our objective was to compare 111In- or 64Cu-DOTA-trastuzumab Fab fragments for imaging small or large s.c. tumor xenografts in athymic mice that display a wide range of human epidermal growth factor receptor-2 (HER2) expression using microSPECT/CT or microPET/CT. Methods Trastuzumab Fab were labeled with 111In or 64Cu by conjugation to 1,4,7,10-tetraazacyclododecane N, N', N'', N'''-tetraacetic acid (DOTA). The purity of 111In- and 64Cu-DOTA-trastuzumab Fab was measured by SDS-PAGE and HPLC. HER2 binding affinity was determined in saturation radioligand binding assays using SKBR-3 cells (1.3 × 106 HER2/cell). MicroSPECT/CT and microPET/CT were performed in athymic mice bearing s.c. BT-20 and MDA-MB-231 xenografts with low (0.5 to 1.6 × 105 receptors/cell), MDA-MB-361 tumors with intermediate (5.1 × 105 receptors/cell) or SKOV-3 xenografts with high HER2 expression (1.2 × 106 receptors/cell) at 24 h p.i. of 70 MBq (10 μg) of 111In-DOTA-trastuzumab Fab or 22 MBq (10 μg) of 64Cu-DOTA-trastuzumab Fab or irrelevant 111In- or 64Cu-DOTA-rituximab Fab. Tumor and normal tissue uptake were quantified in biodistribution studies. Results 111In- and 64Cu-DOTA-trastuzumab were > 98% radiochemically pure and bound HER2 with high affinity (K d = 20.4 ± 2.5 nM and 40.8 ± 3.5 nM, respectively). MDA-MB-361 and SKOV-3 tumors were most clearly imaged using 111In- and 64Cu-DOTA-trastuzumab Fab. Significantly higher tumor/blood (T/B) ratios were found for 111In-DOTA-trastuzumab Fab than 111In-DOTA-rituximab Fab for BT-20, MDA-MB-231 and MDA-MB-361 xenografts, and there was a direct association between T/B ratios and HER2 expression. In contrast, tumor uptake of 64Cu-DOTA-trastuzumab Fab was significantly higher than 64Cu-DOTA-rituximab Fab in MDA-MB-361 tumors but no direct association with HER2 expression was found. Both 111In- and 64Cu-DOTA-trastuzumab Fab imaged small (5 to 10 mm) or larger (10 to 15 mm) MDA-MB-361 tumors. Higher blood, liver, and spleen radioactivity were observed for 64Cu-DOTA-trastuzumab Fab than 111In-DOTA-trastuzumab Fab. Conclusions We conclude that 111In-DOTA-trastuzumab Fab was more specific than 64Cu-DOTA-trastuzumab Fab for imaging HER2-positive tumors, especially those with low receptor density. This was due to higher levels of circulating radioactivity for 64Cu-DOTA-trastuzumab Fab which disrupted the relationship between HER2 density and T/B ratios. Use of alternative chelators that more stably bind 64Cu may improve the association between T/B ratios and HER2 density for 64Cu-labeled trastuzumab Fab
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