Center for Policy Issues: Open Forum

George McGovern shared his interpretations of foreign policy decisions over previous decades, including United States relations with the Soviet Union, Vietnam, Cuba, and Cambodia. Senator McGovern was invited to be a Center for Policy Issues Visiting Scholar at Sacred Heart University in the Fall of 1989. This paper is a transcription of his comments and responses to questions at an Open Forum held at Sacred Heart on September 28, 1989

A Cholecystokinin B Receptor-Specific Aptamer Does Not Activate Receptor Signaling

Targeted nanoparticles which deliver effective doses of chemotherapeutic drugs directly to pancreatic tumors could improve treatment efficacy without the toxicities associated with systemic drug administration. One protein on tumor cells that can be targeted by nanoparticles is a G-protein coupled cell surface receptor, the cholecystokinin B receptor (CCKBR). Previously, we had shown that attaching the CCKBR ligand gastrin to the surface of nanoparticles can enhance their up-take by tumors. The drawback of using gastrin is that it can also activate the receptor, causing tumor cell growth. This study shows that a DNA aptamer that binds to the CCKBR and enhances nanoparticle up-take by tumors does not activate this receptor. PANC-1 cells, a cultured human pancreatic cancer cell line, were treated for 24 h with CCKBR aptamer 1153. Cell lysates were run on Bis-Tris gels, transferred to membranes, blocked in 5% BSA and incubated overnight with primary antibodies, including antibodies directly against phosphorylated-Akt (Ser473), total Akt, and beta-actin, a protein loading control. Although the CCKBR aptamer 1153 is internalized by pancreatic cancer cells in a receptor-mediated fashion, it does not stimulate cell proliferation. Because of this, we anticipate that it will not activate CCKBR signaling. If aptamer 1153 does not activate downstream receptor signaling, our future work will test whether the aptamer could be used to specifically direct drug-containing nanoparticles to tumors, making chemotherapy treatments for pancreatic cancer patients more effective with fewer off-target effects and toxicity

Non-Intrusive Second Law Performance Evaluation of a Domestic Freezer

This paper describes non-intrusive performance testing and second law, exergy-based, performance evaluation of a small, contemporary domestic freezer that used R600a refrigerant. The methodology presented is associated with logging of temperatures and the instantaneous power consumption. It gives a ‘second law of thermodynamics’ perspective on operating performance by providing rational efficiency values and by localizing and quantifying the instantaneous exergy destruction rates. This approach is compared to a more conventional ‘first law’ energy analysis. Suggestions are made for the standardization of such an approach in order to enhance the sustainability of domestic freezers. Keywords: Domestic freezer, Performance testing, Performance evaluation, Exergy

Evaluating Established Methods for Rumen 16S rRNA Amplicon Sequencing With Mock Microbial Populations

peer-reviewedThe rumen microbiome scientific community has utilized amplicon sequencing as an aid in identifying potential community compositional trends that could be used as an estimation of various production and performance traits including methane emission, animal protein production efficiency, and ruminant health status. In order to translate rumen microbiome studies into executable application, there is a need for experimental and analytical concordance within the community. The objective of this study was to assess these factors in relation to selected currently established methods for 16S phylogenetic community analysis on a microbial community standard (MC) and a DNA standard (DS; ZymoBIOMICSTM). DNA was extracted from MC using the RBBC method commonly used for microbial DNA extraction from rumen digesta samples. 16S rRNA amplicon libraries were generated for the MC and DS using primers routinely used for rumen bacterial and archaeal community analysis. The primers targeted the V4 and V3–V4 region of the 16S rRNA gene and samples were subjected to both 20 and 28 polymerase chain reaction (PCR) cycles under identical cycle conditions. Sequencing was conducted using the Illumina MiSeq platform. As the bacteria contained in the microbial mock community were well-classified species, and for ease of explanation, we used the results of the Basic Local Alignment Search Tool classification to assess the DNA, PCR cycle number, and primer type. Sequence classification methodology was assessed independently. Spearman’s correlation analysis indicated that utilizing the repeated bead beating and column method for DNA extraction in combination with primers targeting the 16S rRNA gene using 20 first-round PCR cycles was sufficient for amplicon sequencing to generate a relatively accurate depiction of the bacterial communities present in rumen samples. These results also emphasize the requirement to develop and utilize positive mock community controls for all rumen microbiomic studies in order to discern errors which may arise at any step during a next-generation sequencing protocol

An efficient consistency management algorithm for real-time mobile collaboration

Real time mobile collaboration involves two or more co-workers operating concurrently on a shared document using independent mobile devices. The replicated architecture is attractive for such applications since it does not rely on a central server and a user can continue to work on his or her own local document replica even during disconnection period. Several consistency management algorithms have been proposed, however the resource usage of such algorithms, which is critical in a mobile environment, has not been formally studied. Mobile devices are constrained in terms of memory and processing power, and operate in networking environments with limited bandwidth and transient connectivity. Therefore, algorithms that use resources more effectively improve the quality of the user experience in a mobile environment. ISO 9126-1 considers software to be efficient if it provides a balance between performance, and resource utilisation while performing its function. Therefore, this paper evaluates the efficiency of existing techniques, and proposes a more efficient consistency management algorithm. The new algorithm leverages existing techniques which are shown to be efficient and incorporates a novel history management strategy called partial history copy. Different combinations of these techniques are tested and compared to determine which one is most efficient and thus suitable for mobile usage