Investigating Methods to Reduce Black Bear (Ursus americanus) Visitation to Anthropogenic Food Sources: Conditioned Taste Aversion and Food Removal

Conflicts between humans and black bears (Ursus americanus) jeopardize the safety of both humans and bears, especially when bears become food-conditioned to anthropogenic food sources in areas such as campgrounds. Interest in using non-lethal techniques, such as aversive conditioning, to manage such conflicts is growing. I conducted a captive experiment at The Wildlife Science Center in Minnesota and two field experiments in the La Sal Mountains, Utah, to investigate the effects of taste aversion conditioning using thiabendazole (TBZ) with a novel flavor cue and food removal on black bear food consumption and visitation to human food sources. In 2007, I conducted food trials with 6 captive black bears (3 control, 3 treatment). Controls received 1 kg baked goods scented with a peppermint-canola oil mixture and treatments received 1 kg baked goods also scented with a peppermint-canola oil mixture but mixed with 10-20 g TBZ. In the 2007 field experiment, I baited 24 field sites with 300 g of baked goods during a baseline phase for approximately 3 weeks. Half of these sites were then treated with 10 g of TBZ and camphor during a treatment phase for 4 weeks. In 2008, I baited 22 sites with 300 g of baked goods during a baseline phase for approximately 4 weeks. I then removed food and discontinued baiting at half of the sites for 4 weeks. Infrared cameras and barbed-wire hair snags were established at field sites to document bear visitation. I did not establish taste aversion in treated bears in captivity and bears fully consumed food in the majority of trials. Treating food supplies with 10 g TBZ and camphor flavor did not significantly reduce bear visitation (P = 0.615) or food consumption at field sites (P = 0.58). However, I observed a significant reduction in bear activity at sites where food was removed (P = 0.006). Potential reasons for my failure to reduce bear visitation using thiabendazole include insufficient conditioning, reluctance of bears to desist in investigating sites that previously contained untreated food, and masking of a treatment effect due to continued encounters of sites by new individuals

Performance and loads data from a hover test of a full-scale XV-15 rotor

A hover test of a full-scale XV-15 rotor was conducted at the Outdoor Aerodynamic Research Facility at Ames Research Center. The primary objective of the test was to obtain accurate measurements of the hover performance of the original, metal-blade XV-15 rotor system. Data were acquired for rotor tip Mach numbers ranging from 0.60 to 0.73. This report presents data on rotor performance, rotor wake downwash velocities, and rotor loads

Nitrous oxide emissions in agricultural soils: a review.

The greenhouse gases concentration in the atmosphere have significantly increased since the beginning of the Industrial Revolution. The most important greenhouse gases are CO2, CH4 and N2O, with CH4 and N2O presenting global warming potentials 25 and 298 times higher than CO2, respectively. Most of the N2O emissions take place in soils and are related with agricultural activities. So, this review article aimed at presenting the mechanisms of N2O formation and emission in agricultural soils, as well as gathering and discussing information on how soil management practices may be used to reduce such emissions. The N2O formation in the soil occurs mainly through nitrification and denitrification processes, which are influenced by soil moisture, temperature, oxygen concentration, amount of available organic carbon and nitrogen and soil C/N ratio. Among these factors, those related to soil could be easily altered by management practices. Therefore, understanding the processes of N2O formation in soils and the factors influencing these emissions is fundamental to develop efficient strategies to reduce N2O emissions in agricultural soils

Comparação entre metodologias para cálculo do índice de manejo de carbono do solo em São Luís-MA.

O objetivo desse trabalho foi comparar o IMC calculado a partir de duas metodologias para determinação do teor de C lábil do solo (oxidação do C por K2Cr2O7 em diferentes níveis de acidez e fracionamento físico da matéria orgânica do solo) em solos sob diferentes usos em São Luís-MA

Performance and loads data from a hover test of a 0.658-scale V-22 rotor and wing

A hover test of a 0.658-scale model of a V-22 rotor and wing was conducted at the Outdoor Aerodynamic Research Facility at Ames Research Center. The primary objectives of the test were to obtain accurate measurements of the hover performance of the rotor system, and to measure the aerodynamic interactions between the rotor and wing. Data were acquired for rotor tip Mach numbers ranging from 0.1 to 0.73. This report presents data on rotor performance, rotor-wake downwash velocities, rotor system loads, wing forces and moments, and wing surface pressures

Emissões de N2O de um latossolo após a aplicação de fertilizantes nitrogenados.

O óxido nitroso (N2O) é o principal gás do efeito estufa emitido pelos solos agrícolas e sua emissão é influenciada pelo uso de fertilizantes nitrogenados. Este trabalho avaliou, sob condições controladas, o comportamento das emissões de N2O em amostras de um Latossolo Vermelho, em função da aplicação de duas fontes (nitrato de amônio e ureia) e de três doses (0,11 mg; 0,15 mg e 0,22 mg de N g-1 de solo) de nitrogênio. Os tratamentos foram aplicados na forma de solução, em delineamento inteiramente casualizado, com quatro repetições. Todos os tratamentos aumentaram as emissões de N2O em relação ao controle. O efeito da dose de N sobre as emissões de N2O foi mais pronunciado para a ureia. As emissões foram maiores e ocorreram mais rapidamente nos tratamentos com ureia do que naqueles com nitrato de amônio (maior emissão diária aos 9 e aos 12 dias, respectivamente). As emissões acumuladas ajustaram-se adequadamente a modelos logísticos em todos os tratamentos, indicando que estas curvas representam bem as emissões de N2O induzidas pela aplicação de fertilizantes nitrogenados sob condições controladas. Os resultados podem auxiliar no planejamento de pesquisas similares a serem conduzidas no campo

Efeito de doses de nitrogênio sobre os teores de clorofila e nitrogênio foliar na pereira, cv. Princesinha, cultivada no Vale do São Francisco.

O objetivo desse trabalho foi avaliar os índices de clorofila total, clorofila A e clorofila B e teor de N foliar em pereiras da cultivar Princesinha, cultivada sob condições irrigadas no Semiárido pernambucano

Cruise-Efficient Short Takeoff and Landing (CESTOL): Potential Impact on Air Traffic Operations

The National Aeronautics and Space Administration (NASA) is investigating technological and operational concepts for introducing Cruise-Efficient Short Takeoff and Landing (CESTOL) aircraft into a future US National Airspace System (NAS) civil aviation environment. CESTOL is an aircraft design concept for future use to increase capacity and reduce emissions. CESTOL provides very flexible takeoff, climb, descent and landing performance capabilities and a high-speed cruise capability. In support of NASA, this study is a preliminary examination of the potential operational impact of CESTOL on airport and airspace capacity and delay. The study examines operational impacts at a subject site, Newark Liberty Intemational Airport (KEWR), New Jersey. The study extends these KEWR results to estimate potential impacts on NAS-wide network traffic operations due to the introduction of CESTOL at selected major airports. These are the 34 domestic airports identified in the Federal Aviation Administration's Operational Evolution Plan (OEP). The analysis process uses two fast-time simulation tools to separately model local and NAS-wide air traffic operations using predicted flight schedules for a 24-hour study period in 2016. These tools are the Sen sis AvTerminal model and NASA's Airspace Concept Evaluation System (ACES). We use both to simulate conventional-aircraft-only and CESTOL-mixed-with-conventional-aircraft operations. Both tools apply 4-dimension trajectory modeling to simulate individual flight movement. The study applies AvTerminal to model traffic operations and procedures for en route and terminal arrival and departures to and from KEWR. These AvTerminal applications model existing arrival and departure routes and profiles and runway use configurations, with the assumption jet-powered, large-sized civil CESTOL aircraft use a short runway and standard turboprop arrival and departure procedures. With these rules, the conventional jet and CESTOL aircraft are procedurally separated from each other geographically and in altitude during tenninal airspace approach and departure operations, and each use a different arrival runway. AvTeminal implements its unique Focal-point Scheduling Process to sequence, space and delay aircraft to resolve spacing and overtake conflicts among flights in the airspace and airport system serving KEWR. This Process effectively models integrated arrival and departure operations. AvTerminal assesses acceptance rates and delay magnitude and causality at selected locations, including en route outer boundary fixes, tenninal airspace arrival and departure boundary fixes, terminal airspace arrival merge and departure diverge fixes, and runway landing and takeoff runways. The analysis compares the resulting capacity impacts, flight delays and delay sources between CESTOL and conventional KEWR operations. AvTerminal quantitative results showed that CESTOL has significant capability to increase airport arrival acceptance rates (35-40% at KEWR) by taking advantage of otherwise underused airspace and runways where available. The study extrapolates the AvTerminal-derived KEWR peak arrival and departure acceptance rates to estimate capacity parameter values for each of the OEP airports in the ACES modeling of traffic through the entire NAS network. The extrapolations of acceptance rates allow full, partial or no achievement of CESTOL capacity gains at an OEP airport as determined by assessments of the degree to which local procedures allow leveraging of CESTOL capabilities. These assessments consider each OEP airport's runway geometries, runway system configurations, airport and airspace operations, and potential CESTOL traffic loadings. The ACES modeling, simulates airport and airspace spacing constraints imposed by airport runway system, terminal and en route air traffic control and traffic flow management operations using airport acceptance rates representing conventional-aircraft-only and CESTOL-mixed operations. CEOL aircraft are assumed to have Mach 0.8, and alternatively Mach 0.7, cruise speeds to examine compatibility with conventional aircraft operations in common airspace. The ACES results provides estimates of CESTOL delay impact NAS-wide and at OEP airports due to changes in OEP airport acceptance rates and changes in en route airspace potential conflict rates. Preliminary results show meaningful nationwide delay reductions (20%) due to CESTOL operations at 34 major domestic airports

Influência do biocarvão na retenção de água em argissolo e vertissolo.

O biocarvão é uma forma de carbono resistente à decomposição e sua aplicação ao solo promove melhorias em atributos que em melhores condições para o crescimento das plantas. O objetivo desse trabalho foi avaliar o efeito da adição de diferentes doses de biocarvão sobre a capacidade de retenção de água em um Argissolo e em um Vertissolo. O estudo foi realizado utilizando diferentes doses de biocarvão (0, 25, 50, 75 e 100%, proporção em massa) adicionadas a um Vertissolo e a um Argissolo. O experimento foi conduzido em esquema fatorial 5 x 2 (5 doses de biocarvão x 2 tipos de solo), em delineamento inteiramente casualizado, com três repetições. Nas misturas de solo+biocarvão foram determinadas as quantidades de água retida em diferentes tensões pelo método da centrífuga. A aplicação de biocarvão aumentou a quantidade de água no ponto de murcha permanente e na capacidade de campo do solo tanto no Vertissolo quanto no Argissolo, com efeitos de maior intensidade nesse último. O aumento de 1% na quantidade de biocarvão adicionada ao solo promoveu um aumento de 3,23 g kg-1 na quantidade de água disponível no solo, independentemente do solo avaliado. Assim, o biocarvão apresenta-se como um condicionador de solo com grande potencial para aumentar a retenção de água em solos da região Semiárida