300 research outputs found

    The FCC\u27s Minority Ownership Policies from Broadcasting to PCS

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    The Federal Communication Commission\u27s (FCC\u27s) proposed minority preference scheme for broadcast spectrum allocation has been called into question in the wake of the Supreme Court(s recent decision in Adarand Constructors, Inc. v. Pena. The Authors begin by discussing the development of minority preference schemes in the 1970s and 1980s and the changes in the methods through which the FCC has awarded broadcast licenses. In 1993, the FCC was granted the authority to auction spectrum allocation, provided that the FCC ensured the economic opportunity of minority-owned business under such a competitive bidding regulatory regime. However, this grant of authority presented the FCC with a legal concern: ensuring that the a minority preference scheme was not violative of the Equal Protection Clauses of the Fifth and Fourteenth Amendments. To this end, the FCC established entrepreneurs\u27 blocks in which two spectrum blocks were set-aside for applicants meeting certain financial qualifications. These financial-based eligibility restrictions appeared to create a solid legal foundation. However, the Adarand decision has resulted in the FCC postponing the proposed entrepreneurs\u27 block auction indefinitely. The remainder of the Article is a discussion of the Adarand decision and its effect on the proposed blocks. In particular, the Authors discuss whether the FCC-proposed scheme will survive the strict scrutiny standard imposed by Adarand

    The FCC\u27s Minority Ownership Policies from Broadcasting to PCS

    Get PDF
    The Federal Communication Commission\u27s (FCC\u27s) proposed minority preference scheme for broadcast spectrum allocation has been called into question in the wake of the Supreme Court(s recent decision in Adarand Constructors, Inc. v. Pena. The Authors begin by discussing the development of minority preference schemes in the 1970s and 1980s and the changes in the methods through which the FCC has awarded broadcast licenses. In 1993, the FCC was granted the authority to auction spectrum allocation, provided that the FCC ensured the economic opportunity of minority-owned business under such a competitive bidding regulatory regime. However, this grant of authority presented the FCC with a legal concern: ensuring that the a minority preference scheme was not violative of the Equal Protection Clauses of the Fifth and Fourteenth Amendments. To this end, the FCC established entrepreneurs\u27 blocks in which two spectrum blocks were set-aside for applicants meeting certain financial qualifications. These financial-based eligibility restrictions appeared to create a solid legal foundation. However, the Adarand decision has resulted in the FCC postponing the proposed entrepreneurs\u27 block auction indefinitely. The remainder of the Article is a discussion of the Adarand decision and its effect on the proposed blocks. In particular, the Authors discuss whether the FCC-proposed scheme will survive the strict scrutiny standard imposed by Adarand

    Environment Dictates Dependence on Mitochondrial Complex I for NAD+ and Aspartate Production and Determines Cancer Cell Sensitivity to Metformin

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    Metformin use is associated with reduced cancer mortality, but how metformin impacts cancer outcomes is controversial. Although metformin can act on cells autonomously to inhibit tumor growth, the doses of metformin that inhibit proliferation in tissue culture are much higher than what has been described in vivo. Here, we show that the environment drastically alters sensitivity to metformin and other complex I inhibitors. We find that complex I supports proliferation by regenerating nicotinamide adenine dinucleotide (NAD)+, and metformin's anti-proliferative effect is due to loss of NAD+/NADH homeostasis and inhibition of aspartate biosynthesis. However, complex I is only one of many inputs that determines the cellular NAD+/NADH ratio, and dependency on complex I is dictated by the activity of other pathways that affect NAD+ regeneration and aspartate levels. This suggests that cancer drug sensitivity and resistance are not intrinsic properties of cancer cells, and demonstrates that the environment can dictate sensitivity to therapies that impact cell metabolism. Keywords: cancer metabolism; metformin; biguanide; NAD+/NADH ratio; drug sensitivity; complex I; mitochondria; aspartateNational Institutes of Health (U.S.) (Grant P30CA1405141)National Institutes of Health (U.S.) (Grant GG006413)National Institutes of Health (U.S.) (Grant R01 CA168653)National Institutes of Health (U.S.) (Grant R01 CA201276

    Interactions between the Nse3 and Nse4 Components of the SMC5-6 Complex Identify Evolutionarily Conserved Interactions between MAGE and EID Families

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    The SMC5-6 protein complex is involved in the cellular response to DNA damage. It is composed of 6-8 polypeptides, of which Nse1, Nse3 and Nse4 form a tight sub-complex. MAGEG1, the mammalian ortholog of Nse3, is the founding member of the MAGE (melanoma-associated antigen) protein family and Nse4 is related to the EID (E1A-like inhibitor of differentiation) family of transcriptional repressors.Using site-directed mutagenesis, protein-protein interaction analyses and molecular modelling, we have identified a conserved hydrophobic surface on the C-terminal domain of Nse3 that interacts with Nse4 and identified residues in its N-terminal domain that are essential for interaction with Nse1. We show that these interactions are conserved in the human orthologs. Furthermore, interaction of MAGEG1, the mammalian ortholog of Nse3, with NSE4b, one of the mammalian orthologs of Nse4, results in transcriptional co-activation of the nuclear receptor, steroidogenic factor 1 (SF1). In an examination of the evolutionary conservation of the Nse3-Nse4 interactions, we find that several MAGE proteins can interact with at least one of the NSE4/EID proteins.We have found that, despite the evolutionary diversification of the MAGE family, the characteristic hydrophobic surface shared by all MAGE proteins from yeast to humans mediates its binding to NSE4/EID proteins. Our work provides new insights into the interactions, evolution and functions of the enigmatic MAGE proteins

    Ancient papillomavirus-host co-speciation in Felidae

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    The evolutionary rate of feline papillomaviruses is inferred from the phylogenetic analysis of their hosts, providing evidence for long-term virus-host co-speciatio

    CXC chemokines exhibit bactericidal activity against multidrug-resistant gram-negative pathogens

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    The continued rise and spread of antimicrobial resistance among bacterial pathogens pose a serious challenge to global health. Countering antimicrobial-resistant pathogens requires a multifaceted effort that includes the discovery of novel therapeutic approaches. Here, we establish the capacity of the human CXC chemokines CXCL9 and CXCL10 to kill multidrug-resistant Gram-negative bacteria, including New Delhi metallo-beta-lactamase-1-producing Klebsiella pneumoniae and colistin-resistant members of the family Enterobacteriaceae that harbor the mobile colistin resistance protein MCR-1 and thus possess phosphoethanolamine-modified lipid A. Colistin-resistant K. pneumoniae isolates affected by genetic mutation of the PmrA/PmrB two-component system, a chromosomally encoded regulator of lipopolysaccharide modification, and containing 4-amino-4-deoxy-l-arabinose-modified lipid A were also found to be susceptible to chemokine-mediated antimicrobial activity. However, loss of PhoP/PhoQ autoregulatory control, caused by disruption of the gene encoding the negative regulator MgrB, limited the bactericidal effects of CXCL9 and CXCL10 in a variable, strain-specific manner. Cumulatively, these findings provide mechanistic insight into chemokine-mediated antimicrobial activity, highlight disparities amongst determinants of colistin resistance, and suggest that chemokine-mediated bactericidal effects merit additional investigation as a therapeutic avenue for treating infections caused by multidrug-resistant pathogens

    Benefits of Realist Ontologies to Systems Engineering

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    Applied ontologies have been used more and more frequently to enhance systems engineering. In this paper, we argue that adopting principles of ontological realism can increase the benefits that ontologies have already been shown to provide to the systems engineering process. Moreover, adopting Basic Formal Ontology (BFO), an ISO standard for top-level ontologies from which more domain specific ontologies are constructed, can lead to benefits in four distinct areas of systems engineering: (1) interoperability, (2) standardization, (3) testing, and (4) data exploitation. Reaping these benefits in a model-based systems engineering (MBSE) context requires utilizing an ontology’s vocabulary when modeling systems and entities within those systems. If the chosen ontology abides by the principles of ontological realism, a semantic standard capable of uniting distinct domains, using BFO as a hub, can be leveraged to promote greater interoperability among systems. As interoperability and standardization increase, so does the ability to collect data during the testing and implementation of systems. These data can then be reasoned over by computational reasoners using the logical axioms within the ontology. This, in turn, generates new data that would have been impossible or too inefficient to generate without the aid of computational reasoners

    Ontology of plays for autonomous teaming and collaboration

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    We propose a domain-level ontology of plays for the facilitation of play-based collaborative autonomy among unmanned and manned-unmanned aircraft teams in the Army’s Unmanned Aircraft System (UAS) mission domain. We define a play as a type of plan that prescribes some pattern of intentional acts that are intended to reliably result in some goal in some competitive context, and which specifies one or more roles that are realized by those prescribed intentional acts. The ontology is well suited to be extended to other types of military and nonmilitary unmanned vehicle operations

    The Impact of the Species–Area Relationship on Estimates of Paleodiversity

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    Estimates of paleodiversity patterns through time have relied on datasets that lump taxonomic occurrences from geographic areas of varying size per interval of time. In essence, such estimates assume that the species–area effect, whereby more species are recorded from larger geographic areas, is negligible for fossil data. We tested this assumption by using the newly developed Miocene Mammal Mapping Project database of western North American fossil mammals and its associated analysis tools to empirically determine the geographic area that contributed to species diversity counts in successive temporal bins. The results indicate that a species–area effect markedly influences counts of fossil species, just as variable spatial sampling influences diversity counts on the modern landscape. Removing this bias suggests some traditionally recognized peaks in paleodiversity are just artifacts of the species–area effect while others stand out as meriting further attention. This discovery means that there is great potential for refining existing time-series estimates of paleodiversity, and for using species–area relationships to more reliably understand the magnitude and timing of such biotically important events as extinction, lineage diversification, and long-term trends in ecological structure
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