Tommy Smith

https://arrow.tudublin.ie/scthebk/1015/thumbnail.jp

Ecology of black bears in a bottomland hardwood forest in Arkansas

Population characteristics, growth patterns, reproduction, mortality, food habits, denning, movements, and habitat use of black bears in bottomland hardwood forest were studied on White River National Wildlife Refuge in eastern Arkansas from June 1979 to May 1982. A total of 51 bears was captured 64 times, and 2104 telemetry locations of 28 radioinstrumented bears were obtained. Estimates of population size and density on the 457 km2 Refuge were 130 bears and 1 bear/4.5 km2, respectively. The genetically effective number of bears in the lower White River basin was estimated to be 53 to 130, indicating that the long-term fitness of this closed population is precarious. The composite ratio of males to females in the capture sample was 1.56:1; it did not differ significantly from 1:1 (P\u3c0.05). Capture data suggested a stable age structure, and that females, which reached 14 years of age, were longer-lived than males. Growth was curvilinear in both sexes. Males attained peak body weight by 5 years of age, but females added weight until 9 or 10 years old. Mean weight of adult males (102 kg) was twice that of adult females (52 kg). Approximately one-third of the females successfully bred as 3- year-olds, and all had produced cubs by 6 years of age. All males appeared to be sexually mature by 4 years of age. Mean breeding interval of radio-collared females was 2.4 years. Most litters were born in early February, and mean litter size was 2.3 cubs

An evaluation of vertically stratified traps for censusing small mammal populations

The use of vertically stratified traps for censusing small mammal populations in Loblolly Pine Plantation and Oak-Pine-Mixed Hardwood Forest was evaluated. Trap types and placements included: pitfalls, snap and live traps set in excavated burrows, and snap and live traps set at ground surface. Combinations used for two removal trapping methods were: (1) one pitfall and one snap trap set at ground surface per station, and (2) one snap trap set in a burrow and one at ground surface per station. Live traps were placed in the latter manner. Dominant species of small mammal communities in both habitats were Peromyscus leucopus, Ochrotomys nuttalli, Blarina carolinensis, and Sorex longirostris. Pitfalls did not appear effective for capturing P. leucopus and O. nuttalli, however, the design of this trap type herein may have allowed these rodents to escape capture, and interpretation was withheld. Neither of these species responded differently to snap and live traps set in burrows or at ground surface. In removal trapping, B. carolinensis was captured with greatest efficiency by pitfalls and snap traps set in burrows when each was paired with snap traps set at ground surface. Trap-revealed densities indicated that setting traps in burrows was the most effective method for capturing this species. This trend was also observed in live trapping. Higher numbers of S. longirostris were removed by pitfalls than by snap traps set in burrows or at ground surface. Response to the two placements of snap traps was variable and inconclusive while in live trapping distinctly more captures were made by traps set in burrows. The three methods of vertical trap stratification produced uniform rates of capture for the four cohabiting species. Highest initial captures were observed in live trapping with indication that complete capture of resident populations was accomplished during a five-day trapping session. Small mammals were taken at lower rates in removal trapping with no indication that resident populations were totally removed. This was attributed to a shorter adjustment period of two days used in removal trapping compared to a five-day adjustment period used in live trapping. Additional data were gathered on the distribution, density, standing crop biomass, diel activity, movement, home range, reproductive activity, and body measurements of the four common species

Using the effective weak mixing angle as an input parameter in SMEFT

We implement electroweak renormalisation schemes involving the effective weak mixing angle to NLO in Standard Model Effective Field Theory (SMEFT). After developing the necessary theoretical machinery, we analyse a select set of electroweak precision observables in such input schemes. An attractive feature is that large corrections from top-quark loops appearing in other schemes are absorbed into the definition of the effective weak mixing angle. On the other hand, the renormalisation condition which achieves this involves a large number of flavour-specific SMEFT couplings between the Z boson and charged leptons, motivating simple flavour assumptions such as minimal flavour violation for practical applications. The results of this paper provide a valuable new component for estimating systematic uncertainties in SMEFT fits by performing analyses in multiple input schemes

P3_7 Charged particles in a magnetic field - an integrator

We investigate the accuracy of using a simple numerical integrator (Euler Method) to find how a charged particle moves in a magnetic field. We find that the error depends on the choice of time step, but is not negligible for even small values, as such it is probably not the best method for this

P3_1 A Water Powered Funicular Railway

We are investigating the weight of water needed to overcome frictional forces to power a funicular railway. We find that the amount of water required depends on the angle of the slope, and that angles below ∼ 28◦ are forbidden, and only above ∼ 35◦ do they become physically viable

P3 10 An Alkali Metal Water Bomb

When exposed to water, alkali metals react violently with water to produce a metal hydroxide and hydrogen. Here, we will explore how much energy is released in a typical reaction, and find out how much lithium and water are needed to release the energy equivalent of ‘Gadget’; an atomic bomb dropped in the Nevada Desert in 1945, as part of the ‘Trinity’ project [1]. We find that the total mass of this lithium-water bomb would be around 9.01 ×10^9g

P3 8 Which Earth material is most similar to doonium?

We aim to explore which of the primary metallic candidates (carbon steel, titanium, and aluminium) would most closely resemble doonium, a heavy metal found in the Star Wars universe for constructing starships [1]. Here, we compare the time taken to cut vertically through a 2m tall door with a lightsaber from Season 1 Episode 5 of Star Wars Rebels [2], as the Ghost crew flees from the Grand Inquisitor to the time taken to cut through the three identical doors made from Earth materials mentioned above. We find that the time taken to cut through two doors made from carbon steel, titanium and aluminium are 31.6s, 25.7s, and 15.7s respectively