Synthesis and Studies of a Carbon-13 Labelled Chemical Carcinogen

Derivatives of 6-methylbenzo[a]pyrene enriched to 90% carbon-13 at the methyl carbon were synthesized. Reactions of the carcinogen, 6-chloromethylbenzo[a]pyrene, with nucleophiles under solvolytic conditions were studied kinetically and, using labelled 6-chloromethylbenzo[a]pyrene, the reaction products were studied by CMR. The purpose was to characterize the selectivity of the benzo[a]pyrenyl- 6-methyl carbonium ion in its reactions with some simple nucleophiles and with nucleosides and other nucleic acid components. Although the solvolysis of 6-chloromethylbenzo[a]pyrene in aqueous/organic solution is first order, information about the course of the reaction can be obtained, under certain circumstances, from rate constants. Thus, if the rate of solvolysis is slowed down by the addition of chloride ion, it can be increased by the addition of nucleophiles which compete for the carbonium ion. By using this inhibition of the common ion effect method, it was determined that the selectivity of the benzo[a]pyrenyl-6-methyl carbonium ion for reaction with various nucleophiles is generally in line with, yet distinct from that of other relatively stable carbonium ions. The order of nucleophilic strength of the simple nucleophiles studied is: aniline \u3e N3- \u3e Cl \u3epyridine \u3e n-propylamine \u3eOH- \u3e diethylamine \u3e H2O. Nucleosides, nucleotides and their deoxy analogs containing adenine, guanine or cytosine were found to be nucleophilic toward the carbonium ion while those containing uracil and thymine were not

A Decision Framework for Allocation of Constellation-Scale Mission Compute Functionality to Ground and Edge Computing

This paper explores constellation-scale architectural trades, highlights dominant factors, and presents a decision framework for migrating or sharing mission compute functionality between ground and space segments. Over recent decades, sophisticated logic has been developed for scheduling and tasking of space assets, as well as processing and exploitation of satellite data, and this software has been traditionally hosted in ground computing. Current efforts exist to migrate this software to ground cloud-based services. The option and motivation to host some of this logic “at the edge” within the space segment has arisen as space assets are proliferated, are interlinked via transport networks, and are networked with multi-domain assets. Examples include edge-based Battle Management, Command, Control, and Communications (BMC3) being developed by the Space Development Agency and future onboard computing for commercial constellations. Edge computing pushes workload, computation, and storage closer to data sources and onto devices at the edge of the network. Potential benefits of edge computing include increased speed of response, system reliability, robustness to disrupted networks, and data security. Yet, space-based edge nodes have disadvantages including power and mass limitations, constant physical motion, difficulty of physical access, and potential vulnerability to attacks. This paper presents a structured decision framework with justifying rationale to provide insights and begin to address a key question of what mission compute functionality should be allocated to the space-based edge , and under what mission or architectural conditions, versus to conventional ground-based systems. The challenge is to identify the Pareto-dominant trades and impacts to mission success. This framework will not exhaustively address all missions, architectures, and CONOPs, however it is intended to provide generalized guidelines and heuristics to support architectural decision-making. Via effects-based simulation and analysis, a set of hypotheses about ground- and edge-based architectures are evaluated and summarized along with prior research. Results for a set of key metrics and decision drivers show that edge computing for specific functionality is quantitatively valuable, especially for interoperable, multi-domain, collaborative assets

Proliferated LEO Autonomy Architecture for Capability with Scalability

A next generation space architecture focused on proliferated low-Earth Orbit (p-LEO) constellations holds the promise of improved situational awareness, responsiveness, and resiliency. A variety of proliferated space constellation efforts are underway in the National Security Space Arena, all demanding innovations in ubiquitous satellite command, control, and communications. Whether communications, science, or defense missions, the expansion into PLEO constellations drives new demands upon autonomy, software, and communications architectures. Previous groundbreaking autonomy work was performed on the Deep Space 1 mission, which eventually led to NASA Mars and Earth Observing-1 autonomy. In Autonomous Rendezvous, Proximity Operations, and Docking (ARPOD), Defense Advanced Research Projects Agency (DARPA)\u27s Orbital Express and the Air Force XSS-10 mission helped establish the state of the art. While similarities exist, mission autonomy for these individual spacecraft missions fundamentally differs from PLEO constellations in their demands and constraints

Bulletin agrométéorologique - Situation au 30 juin 2010

A la fin du mois de juin, les conditions météorologiques peuvent être qualifiées de globalement bonnes sur la plus grande partie du territoire belge. De bons rendements sont annoncés sans toutefois atteindre les rendements exceptionnels comme ceux du blé de l’an dernier. Les analyses spatiales dérivées de la télédétection confirment cette tendance favorable tout en indiquant une hétérogénéité importante dans certaines régions du pays qui peut être mise sur le compte de précipitations orageuses localisées. Les conditions climatiques des prochaines semaines seront déterminantes pour conserver tous les bons potentiels de rendement des cultures et éviter que la situation ne se dégrade pour les zones à plus faible potentiel

Bulletin agrométéorologique - Situation au 21 juin 2009

Depuis le dernier bulletin publié fin avril, les conditions météorologiques ont été fort proches des normales avec toutefois quelques épisodes orageux qui ont pu causer ça et là des dégâts aux cultures. La végétation semble avoir ralenti davantage sa croissance que ce qui s’observe d’habitude depuis dix ans, cela en particulier dans le Nord et le Nord-Ouest du pays, probablement en raison des conditions pluvieuses rencontrées dans ces zones. Cependant les prévisions de rendements à l’échelle nationale ne semblent pas être affectées. A l’exception du maïs, les rendements s’annoncent meilleurs que la moyenne des quatre dernières années

Bulletin agrométéorologique - Situation au 30 avril 2009

Alors que l’on pouvait craindre les conséquences de l’hiver froid que nous avons connu cette année, il apparaît, au niveau de nos indicateurs météorologiques et de nos indicateurs spatiaux dérivés de la télédétection, que les grandes cultures ont dans l’ensemble bien passé l’hiver et elles ont largement rattrapé le retard accumulé au cours des mois d’hiver et du tout début de printemps. Ceci se vérifie également sur le terrain où les stades phénologiques sont très proches de la situation normale. Aucune prévision de rendement n’est faite à ce stade

Outcomes to Objectives: Learning About Quality Assessment

Recently assessment has become an important component of student affairs and higher education to assist in determining the effect and impact of programs and educational initiatives. To embrace this trend, the Office of Housing and Residence Life at Ball State University (IN) created learning outcomes for students living in residence halls. Through reflective questioning, discussion, and assessment, the Residence Life program strives to further the development and learning experience of students

Limiting absorption principle for the dissipative Helmholtz equation

Adapting Mourre's commutator method to the dissipative setting, we prove a limiting absorption principle for a class of abstract dissipative operators. A consequence is the resolvent estimates for the high frequency Helmholtz equation when trapped trajectories meet the set where the imaginary part of the potential is non-zero. We also give the resolvent estimates in Besov spaces

Melt water input from the Bering Glacier watershed into the Gulf of Alaska

The annual runoff from the melting of large glaciers and snow fields along the northern perimeter of the Gulf of Alaska is a critical component of marine physical and biological systems; yet, most of this freshwater is not measured. Here we show estimates of melt for the watershed that contains the largest and longest glacier in North America, the Bering Glacier. The procedure combines in situ observations of snow and ice melt acquired by a long-term monitoring program, multispectral satellite observations, and nearby temperature measurements. The estimated melt is 40 km3 per melt season, ± 3.0 km3, observed over the decadal period, 2002–2012. As a result of climate change, these estimates could increase to 60 km3/yr by 2050. This technique and the derived melt coefficients can be applied to estimate melt from Alaska to Washington glaciers

Outcomes to Objectives: Learning About Quality Assessment

Recently assessment has become an important component of student affairs and higher education to assist in determining the effect and impact of programs and educational initiatives. To embrace this trend, the Office of Housing and Residence Life at Ball State University (IN) created learning outcomes for students living in residence halls. Through reflective questioning, discussion, and assessment, the Residence Life program strives to further the development and learning experience of students