Trajectories for the 1976-1980 grand tour opportunities. Volume 1 - Graphic and summary trajectory data

Trajectories for 1976 to 1980 Grand Tour

Agriculture and agri-food Canada’s salinity tolerance testing laboratory

Non-Peer Reviewe

Engaging Rural Nevadans in Participatory Research to Explore and Explain the Community Food and Physical Activity Context

The purpose of this study was to engage residents of four rural Nevada communities to explain local resources and readiness to address environmental challenges to weight healthy lifestyles. Residents engaged in HEAL MAPPS™, a participatory research approach using photomapping and community conversations to document lived experiences of place-based resources as supports or barriers. Data were triangulated to scale community readiness-to-change. This study focuses on a description of methods and qualitative findings. Healthy food unavailability emerged consistently among communities as a barrier; produce options were limited and many residents relied on convenience foods. Physical activity opportunities were available, yet access was a barrier. Transportation-related issues emerged as barriers to healthy eating and physical activity. Communities ranged between “vague awareness” and “preplanning” on readiness-to-change. Local data and shared knowledge of the obesogenic context can inform community policy and environmental improvements that promote health and enhance quality of life for rural populations

An observation of spin-valve effects in a semiconductor field effect transistor: a novel spintronic device

We present the first spintronic semiconductor field effect transistor. The injector and collector contacts of this device were made from magnetic permalloy thin films with different coercive fields so that they could be magnetized either parallel or antiparallel to each other in different applied magnetic fields. The conducting medium was a two dimensional electron gas (2DEG) formed in an AlSb/InAs quantum well. Data from this device suggest that its resistance is controlled by two different types of spin-valve effect: the first occurring at the ferromagnet-2DEG interfaces; and the second occuring in direct propagation between contacts.Comment: 4 pages, 2 figure

Wave Packet Echoes in the Motion of Trapped Atoms

We experimentally demonstrate and systematically study the stimulated revival (echo) of motional wave packet oscillations. For this purpose, we prepare wave packets in an optical lattice by non-adiabatically shifting the potential and stimulate their reoccurence by a second shift after a variable time delay. This technique, analogous to spin echoes, enables one even in the presence of strong dephasing to determine the coherence time of the wave packets. We find that for strongly bound atoms it is comparable to the cooling time and much longer than the inverse of the photon scattering rate

Absolute ion detection efficiencies of microchannel plates and funnel microchannel plates for multi-coincidence detection

Modern momentum imaging techniques allow for the investigation of complex molecules in the gas phase by detection of several fragment ions in coincidence. For these studies, it is of great importance that the single-particle detection efficiency e is as high as possible, as the overall efficiency scales with e over n, i.e. the power of the number of detected particles. Here we present measured absolute detection efficiencies for protons of several micro-channel plates (MCPs), including efficiency enhanced "funnel MCPs". Furthermore, the relative detection efficiency for two-, three-, four-, and five-body fragmentation of CHBrClF has been examined. The "funnel" MCPs exhibit an efficiency of approx. 90 percent, gaining a factor of 24 (as compared to "normal" MCPs) in case of a five-fold ion coincidence detection

Polarization-dependent frequency shifts from Rb-3He collisions

We present measurements of the frequency shift of the Rb electron-paramagnetic-resonance (EPR) line in the presence of nuclear-polarized 3He gas for the temperature range of 30 to 85 °C. The frequency shift is due to the Fermi-contact interaction between the Rb valence electron and the polarized 3He nucleus. Expressions for both the frequency shift and the spin-exchange cross section are derived in terms of the strength of this contact interaction. From these expressions and the measured frequency shift, we estimate the Rb-3He spin-exchange cross section. The Rb EPR frequency shift, which is 53 kHz for a 100% polarized 10-amagat 3He sample at 50 °C, can be used to determine the absolute polarization of nuclear polarized 3He targets. From these measurements, one can also predict the shift of the 3He NMR line due to a polarized Rb vapor

Detection and elimination of cellular bottlenecks in protein-producing yeasts

Yeasts are efficient cell factories and are commonly used for the production of recombinant proteins for biopharmaceutical and industrial purposes. For such products high levels of correctly folded proteins are needed, which sometimes requires improvement and engineering of the expression system. The article summarizes major breakthroughs that led to the efficient use of yeasts as production platforms and reviews bottlenecks occurring during protein production. Special focus is given to the metabolic impact of protein production. Furthermore, strategies that were shown to enhance secretion of recombinant proteins in different yeast species are presented

Sex-specific disruption of murine midbrain astrocytic and dopaminergic developmental trajectories following antenatal GC treatment

The mammalian midbrain dopaminergic systems arising in the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) are critical for coping behaviours and are implicated in neuropsychiatric disorders where early life challenges comprise significant risk factors. Here, we aimed to advance our hypothesis that glucocorticoids (GCs), recognised key players in neurobiological programming, target development within these systems, with a novel focus on the astrocytic population. Mice received antenatal GC treatment (AGT) by including the synthetic GC, dexamethasone, in the mothers' drinking water on gestational days 16-19; controls received normal drinking water. Analyses of regional shapes and volumes of the adult SNc and VTA demonstrated that AGT induced long-term, dose-dependent, structural changes that were accompanied by profound effects on astrocytes (doubling/tripling of numbers and/or density). Additionally, AGT induced long-term changes in the population size and distribution of SNc/VTA dopaminergic neurons, confirming and extending our previous observations made in rats. Furthermore, glial/neuronal structural remodelling was sexually dimorphic and depended on the AGT dose and sub-region of the SNc/VTA. Investigations within the neonatal brain revealed that these long-term organisational effects of AGT depend, at least in part, on targeting perinatal processes that determine astrocyte density and programmed cell death in dopaminergic neurons. Collectively, our characterisation of enduring, AGT-induced, sex-specific cytoarchitectural disturbances suggests novel mechanistic links for the strong association between early environmental challenge (inappropriate exposure to excess GCs) and vulnerability to developing aberrant behaviours in later life, with translational implications for dopamine-associated disorders (such as schizophrenia, ADHD, autism, depression), which typically show a sex bia