3 dimensional proton beam writing for micro electromechanical systems applications.

Proton beam writing is a direct write lithographic technique that uses finely focused MeV proton beams to create structures in a target material. The depth the protons travel in a material is dependent on its energy, this unique property of proton beams allow multi level structures to be created in materials. PBW has been demonstrated successfully on semiconductor materials, glass and polymers. This thesis is a study of the application of PBW in creating Micro Electro-Mechanical Systems (MEMS) in a polymer SU 8 and SU 8 polymer nano composite with silver, and shows experimental steps, theory and computer simulations involved in creating an electrostatic actuated micro-gripping device. Proton beam writing in silver SU 8 composite results in the creation of electrically conducting microstructures. The unique predictability of the range of protons in materials is leveraged in the creating of free standing conducting cantilevers structures which are used as the building blocks for a micro gripping device. The electrostatic actuation has been modelled using a finite element modelling software Sugar 3.1, and the results are comparable with actual actuations in a realized micro-gripping device

The species analyzed in this study, along with species abbreviations, migration class, foraging guild, number of lat-long blocks analysed, and the median slope of mean arrival date (MAD) as a function of minimum spring temperature over all lat-long blocks.

1<p>Technically, all of these species may be considered Neotropical migrants, but here we define those that winter at least partially in the U.S. as short distance migrants.</p>2<p>A - aerial insectivore, F - foliage gleaner, G - ground gleaner.</p

A model of increased temperature sensitivity in low seasonality environments.

<p>Seasonal variation in average monthly temperatures from January to June in Atlanta (solid) and Montreal (dashed) based on long term averages from weather.com (black) and under a seasonally uniform warming scenario of +2°C (gray). Dotted lines indicate the predicted arrival dates of a hypothetical species that based its arrival on an average temperature of 19°C under each of the four scenarios. The same degree of warming would result in a greater shift in arrival date in Atlanta.</p

Explaining interspecific variation in phenological response.

<p>(A) Mean arrival date (averaged over both year and longitude) as a function of latitude for 18 bird species, depicting the rate at which various species advance northward during migration. (B) Boxplots showing the variation in the slope of the trend in arrival date with minimum spring temperature for each species, with more negative values reflecting earlier arrival. +, p<0.10; *, p<0.05; **, p<0.01. (C) Relationship between migration time (from (A)) and the median phenological response of arrival date to temperature. (D) Residuals of the phenological response to temperature after controlling for migration time and migration distance as a function of niche breadth. Species codes are given in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031662#pone-0031662-t001" target="_blank">Table 1</a>.</p

Geographic variation in phenological response and example trajectories of temperature and arrival date.

<p>Geographic variation in the mean shift in arrival date per °C change in minimum spring temperature for four bird species (right-hand column). The left-hand column depicts changes in both minimum spring temperature (solid line) and arrival date (dashed line) through time for one example region (indicated by arrow) for each species. Note that the arrival date axis increases towards the bottom. Photo credits: red-eyed vireo, Dario Sanches; scarlet tanager, Steve Maslowski; great-crested flycatcher, Matt Ward; indigo bunting, Kevin Bolton.</p

Estimating arrival date from temporal occupancy patterns.

<p>Proportion of checklist locations at which the House Wren (<i>Troglodytes aedon</i>) was observed from Julian days 80–180 (roughly 10 March to 30 June) within a 2-degree lat-long block centered at 41°N and 73°W in 2008 and 2009. Heavy line is the best fitting logistic curve to the data, and the vertical dotted line indicates the inflection point of that curve which is used as an estimate of mean arrival date. The shaded area indicates the region in which occupancy is between 2.5% and 97.5% of the asymptotic value, and the width of this area was used as a confidence interval on the arrival date estimate for weighting purposes.</p

Raw simulation results, no zero sum, tropical origin

Raw simulation results, no zero sum, tropical origi

Coyle&Hurlbert_GEB

Data files and code for conducting analyses described in the associated publication. Includes a README file

Spring arrival dates for the red-eyed vireo.

<p>Spring arrival dates estimated from citizen science data collection efforts for the red-eyed vireo (<i>Vireo olivaceus</i>) across 2° lat-long-blocks in eastern North America from 2002–2010.</p

cbc.abund

cbc.abun