Since 2002 Perimeter Institute has been recording seminars, conference talks, and public outreach events using video cameras installed in our lecture theatres. Perimeter now has 7 formal presentation spaces for its many scientific conferences, seminars, workshops and educational outreach activities, all with advanced audio-visual technical capabilities. Recordings of events in these areas are all available On-Demand from this Video Library and on Perimeter Institute Recorded Seminar Archive (PIRSA). PIRSA is a permanent, free, searchable, and citable archive of recorded seminars from relevant bodies in physics. This resource has been partially modelled after Cornell University's arXiv.org.
Study of rare decays is an important approach for exploring physics beyond the Standard Model (SM). The branching ratio of the helicity suppressed p ? e? decay, is one of the most accurately calculated decay process involving hadrons and has so far provided the most stringent test of the hypothesis of electron-muon universality in weak interactions.
The goal of Total Body Irradiation (TBI) is to deliver a uniform dose of radiation to the entire body, to destroy cancerous cells. Since the human body is not uniform in either density or thickness, it is difficult to deliver a uniform dose. A novel, Aperture Modulated, Total Body Irradiation (AMTBI) technique was introduced by researchers at the Tom Baker Cancer Centre to address this problem. The AMTBI technique reduces the dose deviation along the midline in the longitudinal direction to less than 5%, as compared to 15% with conventional TBI.
This research focuses on finding analytical solutions to the mechanical bidomain model of cardiac tissue. In particular, a perturbation expansion is used to analyze the equations, with the perturbation parameter being inversely proportional to the spring constant coupling the intracellular and extracellular spaces. The results indicate that the intracellular and extracellular pressures are not equal, and that the two spaces move relative to each other.
3D moment invariants (3DMIs) are mathematical spatial descriptors designed to be invariant to scaling, translation and rotation. We propose to characterize the spatial distribution of positron emission tomography (PET) images using 3DMIs. We have used 3DMIs to characterize the spatial distribution of PET brain images recorded from subjects with Parkinson's Disease (PD) and healthy controls. 3DMIs were found to accurately describe the 3D texture of PET images despite changes in the size and orientation of the participating subjects in the PET scanner.
Melanie will discuss how she has and collaborators have applied physics techniques to advance the understanding of the optics of the eye, and to develop novel diagnostic and therapeutic approaches for eye diseases.
The magnetic properties of ceramic samples of Gd1.98R0.02CuO4 R= Ca Sr Th were studied and compared with Gd2CuO4. The results showed weak ferromagnetic ordering in all samples. We observed two magnetic ordering temperatures in the heat capacity measurement a sharp peak at TN(Gd) 6.5 K that can be attributed to the Neel temperature of Gd3+ ions and the second transition temperature at about 20 K that suggested to the magnetic interactions of Gd-Cu. The third anomaly was seen at TN(Cu)=280 K in susceptibility measurements.
Epitaxial MnSi grown on Si (111) offers new opportunities in the development of spin-dependent transport in helical magnets. Helical magnets are a class of noncollinear structures that have shown promise as a material for spin-dependent electron transport studies.The helical magnets are of particular interest in spintronics because in these magnets the electron spins spiral about a particular crystallographic direction, this property can allow for control over electron spin.
Pb2CrO5 have received considerable interests due to their potentials applications in UV radiation measuring devices, visible and UV light photodetectors. In this research we are examining the structural, electronic, magnetic, and thermal properties of polycrystalline Pb2-xLaxCrO5. Samples have been prepared using a solid state solution technique. The temperature dependent magnetic measurements reveal a transition in the Pb2CrO5 and La doped samples near 300 K.
Heavy-hole spin states have been proposed as a robust qubit candidate. Nevertheless, the coupling of the hole spins to nuclei in the surrounding medium likely limits hole-spin coherence and has, until very recently, been overlooked. We describe the spin decoherence of a heavy-hole in a semiconductor quantum dot, subject to spin echo pulses. We do so both analytically and numerically for an experimentally realistic number (10^4) of nuclear spins.