A Social Network Analysis Of Hamadryas Baboons

The study of animal sociality investigates the immediate and long-term consequences that a social structure has on its group members. Typically, social behavior is observed from interactions between two individuals at the dyadic level. However, a new framework for studying social behavior has emerged that allows the researcher to assess social complexity at multiple scales. Social Network Analysis has been recently applied in the field of ethology, and this novel tool enables an approach of focusing on social behavior in context of the global network rather than limited to dyadic interactions. This new technique was applied to a group of captive hamadryas baboons (Papio hamadryas hamadryas) in order to assess how overall network topology of the social group changes over time with the decline of an aging leader male. Observations on aggressive, grooming, and proximity spatial interactions were collected from three separate years in order to serve as `snapshots¿ of the current state of the group. Data on social behavior were collected from the group when the male was in prime health, when the male was at an old age, and after the male¿s death. A set of metrics was obtained from each time period for each type of social behavior and quantified a change in the patterns of interactions. The results suggest that baboon social behavior varies across context, and changes with the attributes of its individual members. Possible mechanisms for adapting to a changing social environment were also explored.

Vibrational Relaxation of N2O (v2) by Atomic Oxygen Measured by Tunable Diode Laser Absorption Spectroscopy

Through the use of Transient Diode Laser Absorption Spectroscopy (TDLAS), the rate coefficient for the vibrational relaxation of N2O (ν2) by O(3P) at room temperature (32 ºC)) was determined to be (1.51 ± 0.11)x10-12 cm3molecule-1sec-1. A Q-switched, frequency quadrupled (266 nm) Nd:YAG laser pulse was used as the pump for this experiment. This pulse caused the photodissociation of O3 into O2 and O atoms.Excited oxygen (O(1D)) was collisionally quenched to ground state (O(3P)) by Ar and/or Xe. Photodissociation also caused a temperature jump within the system, exciting the ν2 state of N2O molecules. Population in the ν2 state was monitored through a TDLASobservation of a ν3 transition. Data were fit using a Visual Fortran 6.0 Global Fitting program. Analysis of room temperature data taken using only Ar to quench O atoms to the ground state gave the same rate coefficient as analysis of data taken using an Ar/Xe mixture, suggesting Ar alone is a sufficient bath gas. Experimentation was alsoperformed at -27 ºC and -82 ºC for a temperature dependence analysis. A linear regression analysis gave a rate coefficient dependence on temperature of ... for the rate coefficient of the vibrational relaxation of N2O (ν2) by atomic oxygen.

Transport of Hydraulic Fracturing Water and Wastes in the Susquehanna River Basin, Pennsylvania

The development of the Marcellus Shale gas play in Pennsylvania and the northeastern United States has resulted in significant amounts of water and wastes transported by truck over roadways. This study used geographic information systems (GIS) to quantify truck travel distances via both the preferred routes (minimum distance while also favoring higher-order roads) as well as, where available, the likely actual distances for freshwater and waste transport between pertinent locations (e. g., gas wells, treatment facilities, freshwater sources). Results show that truck travel distances in the Susquehanna River Basin are greater than those used in prior life-cycle assessments of tight shale gas. When compared to likely actual transport distances, if policies were instituted to constrain truck travel to the closest destination and higher-order roads, transport mileage reductions of 40-80% could be realized. Using reasonable assumptions of current practices, greenhouse gas (GHG) emissions associated with water and waste hauling were calculated to be 70-157 MT CO2 eq per gas well. Furthermore, empty so-called backhaul trips, such as to freshwater withdrawal sites or returning from deep well injection sites, were found to increase emissions by an additional 30%, underscoring the importance of including return trips in the analysis. The results should inform future life-cycle assessments of tight shale gases in managed watersheds and help local and regional governments plan for impacts of transportation on local infrastructure. (C) 2013 American Society of Civil Engineers.

Polymerization of Styrene and Cyclization to Macrocyclic Polystyrene in a One-Pot, Two-Step Sequence

Dibrominated polystyrene (BrPStBr) was produced by atom transfer radical polymerization (ATRP) at 80 degrees C, using the bifunctional initiator benzal bromide to afford the telechelic precursor. The ATRP reaction was stopped around 40% monomer conversion and directly converted into an radical trap-assisted atom transfer radical coupling (RTA-ATRC) reaction by lowering the temperature to 50 degrees C, and adding the radical trap 2-methyl-2-nitrosopropane (MNP) along with additional catalyst, reducing agent, and ligand to match ATRC-type reaction conditions. In an attempt to induce intramolecular coupling, rather than solely intermolecular coupling and elongation, the total reaction volume was increased by the addition of varying amounts of THF. Cyclization, along with intermolecular coupling and elongation, occurred in all cases, with the extent of ring closure a function of the total reaction volume. The cyclic portion of the coupled product was found to have a (G) value around 0.8 by GPC analysis, consistent with the reduction in hydrodynamic volume of a cyclic polymer compared to its linear analog. Analysis of the sequence by H-1 NMR confirmed that propagation was suppressed nearly completely during the RTA-ATRC phase, with percent monomer conversion remaining constant after the ATRP phase. (C) 2013 Elsevier Ltd. All rights reserved.