Determinants Associated to Zeta Matrices of Posets

We consider the matrix ${\frak Z}_P=Z_P+Z_P^t$, where the entries of $Z_P$ are the values of the zeta function of the finite poset $P$. We give a combinatorial interpretation of the determinant of ${\frak Z}_P$ and establish a recursive formula for this determinant in the case in which $P$ is a boolean algebra.Comment: 14 pages, AMS-Te

Nanodielectics (A "Universal" Panacea for Solving All Electrical Insualation Problems?)

This text summarizes the keynote presentation that is based on the full-length paper of the same title. Dr. Fréchette's oral presentation should not be seen as a summary of the “Brainstorm paper” but a glance at some major accomplishments, hinrances and still remaining questions relative to nanodielectrics. Are nanodielectrics a “universal” panacea? The answer to that question is no - but they've got a lot of potential

Behavior of polyethylene-based nanocomposites containing multi-layer graphene filler

open4siIn this research, the results regarding the characterization of electrical and mechanical properties of a low-density polyethylene (LDPE) - graphene-like (G) nanocomposite are presented. The processing technique used to fabricate the material was high-energy ball milling. This method was utilized to fabricate samples with a filler loading ranging from 1 wt% up to 7wt%. Low voltage broadband dielectric spectroscopy (BDS), erosion tests and breakdown tests (BD) were the measurements carried out in order to characterize the electrical behavior of the fabricated composites. Then, some of the mechanical properties of the LDPE-G nanocomposites were determined with dynamic mechanical analysis (DMA) and, finally, the crystalline structure of the material was investigated with differential scanning calorimetry (DSC).embargoed_20200114Rosi, G.F.; Frechette, M.; David, E.; Fabiani, D.Rosi, G.F.; Frechette, M.; David, E.; Fabiani, D

Bargaining and reputation: an experiment on bargaining in the presence of behavioural types

We conduct a series of laboratory experiments to understand what role commitment and reputation play in bargaining. The experiments implement the Abreu and Gul (2000) bargaining model that demonstrates how introducing behavioral types, which are obstinate in their demands, creates incentives for all players to build reputations for being hard bargainers. The data are qualitatively consistent with the theory, as subjects mimic induced types. Furthermore, we find evidence for the presence of complementary types, whose initial demands acquiesce to induced behavioural demands. However, there are quantitative deviations from the theory: subjects make aggressive demands too often and participate in longer conflicts before reaching agreements. Overall, the results suggest that the Abreu and Gul (2000) model can be used to gain insights to bargaining behavior, particularly in environments where the process underlying obstinate play is well established

1972 Ruby Yearbook

A digitized copy of the 1972 Ruby, the Ursinus College yearbook.https://digitalcommons.ursinus.edu/ruby/1075/thumbnail.jp

Engineering visible light emitting point defects in Zr-implanted polycrystalline AlN films

We have investigated the impact of thermal annealing gaseous atmosphere of argon, nitrogen, and forming gas on the structural and optical properties of thin polycrystalline AlN films subjected to high-energy zirconium ions implantation. X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and atomic force microscopy measurements show that the structural and morphological properties of the Zr-implanted AlN films depend on the annealing gaseous environment. Post-implantation annealing under argon atmosphere yields the lowest structured surface roughness with increased grain size. Photoluminescence spectroscopy revealed multiple point defects and defect complexes related emission bands in the visible range. A series of absorption bands have been observed using photoluminescence excitation spectroscopy. The origin of the emission or absorption bands is identified and attributed to various types of point defects and defect complexes, theoretically reported for AlN. New emission and absorption peaks at 1.7eV (730nm) and 2.6eV (466nm), respectively, have been identified and attributed to the (ZrAl–VN)0 defect complexes

Autonomy of Nations and Indigenous Peoples and the Environmental Release of Genetically Engineered Animals with Gene Drives

This article contends that the environmental release of genetically engineered (GE) animals with heritable traits that are patented will present a challenge to the efforts of nations and indigenous peoples to engage in self‐determination. The environmental release of such animals has been proposed on the grounds that they could function as public health tools or as solutions to the problem of agricultural insect pests. This article brings into focus two political‐economic‐legal problems that would arise with the environmental release of such organisms. To address those challenges, it is proposed that nations considering the environmental release of GE animals must take into account the underlying circumstances and policy failures that motivate arguments for the use of the modified animals. Moreover, countries must recognize that the UN International Covenant on Civil and Political Rights and the UN International Covenant on Economic, Social and Cultural Rights place on them an obligation to ensure that GE animals with patented heritable traits are not released without the substantive consent of the nations or indigenous peoples that could be affected

Understanding summertime thermal refuge use by adult Atlantic salmon using remote sensing, river temperature monitoring, and acoustic telemetry

Adult Atlantic salmon (Salmo salar) return to natal rivers several months before spawning and during summer can be subjected to temperatures that exceed their upper temperature tolerance limits. Salmon use thermal refuges to minimize exposure to high temperatures, but little information exists regarding behavioral thermoregulation by adult Atlantic salmon. We examined behavioral thermoregulation by Atlantic salmon during summer in-river residence in a Quebec river with a novel combination of thermal infrared remote sensing, river temperature monitoring, and acoustic telemetry. Adults engaged in behavioural thermoregulation at cooler ambient river temperatures (17–19 °C) than previously recorded for this species and maintained body temperature within a narrow range (16–20 °C) via use of cool and warm refuges. Adults used large, stable, stratified pools as refuges, allowing multiple individuals to thermoregulate simultaneously without leaving the pool. Low river discharge and high temperatures can be physical barriers to salmon migration, preventing them from accessing suitable refuges (e.g., pools). Identifying and maintaining connectivity to thermal refuges may be critical for persistence of Atlantic salmon populations as climate changes and rivers warm

Internal charge behaviour of nanocomposites

The incorporation of 23 nm titanium dioxide nanoparticles into an epoxy matrix to form a nanocomposite structure is described. It is shown that the use of nanometric particles results in a substantial change in the behaviour of the composite, which can be traced to the mitigation of internal charge when a comparison is made with conventional TiO2 fillers. A variety of diagnostic techniques (including dielectric spectroscopy, electroluminescence, thermally stimulated current, photoluminescence) have been used to augment pulsed electro-acoustic space charge measurement to provide a basis for understanding the underlying physics of the phenomenon. It would appear that, when the size of the inclusions becomes small enough, they act co-operatively with the host structure and cease to exhibit interfacial properties leading to Maxwell-Wagner polarization. It is postulated that the particles are surrounded by high charge concentrations in the Gouy-Chapman-Stern layer. Since nanoparticles have very high specific areas, these regions allow limited charge percolation through nano-filled dielectrics. The practical consequences of this have also been explored in terms of the electric strength exhibited. It would appear that there was a window in which real advantages accrue from the nano-formulated material. An optimum loading of about 10% (by weight) is indicated