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Bent silicon crystals mounted on high-accuracy angular actuators were installed in the CERN Super Proton Synchrotron (SPS) and extensively tested to assess the feasibility of crystal-assisted collimation in circular hadron colliders. The adopted layout was exploited and regularly upgraded for about a decade by the UA9 Collaboration. The investigations provided the compelling evidence of a strong reduction of beam losses induced by nuclear inelastic interactions in the aligned crystals in comparison with amorphous orientation. A conceptually similar device, installed in the betatron cleaning insertion of CERN Large Hadron Collider (LHC), was operated through the complete acceleration and storage cycle and demonstrated a large reduction of the background leaking from the collimation region and radiated into the cold sections of the accelerator and the experimental detectors. The implemented layout and the relevant results of the beam tests performed in the SPS and in the LHC with stored proton and ion beams are extensively discussed.

The objective was to determine effects of manual transrectal ablation of the largest (dominant) ovarian follicle on days 7 or 8 of the cycle (estrus = day 0) to synchronize wave emergence before superovulation. Superovulation was performed in 167 donors, 32 nulliparous, 36 primiparous and 99 multiparous Holsteins. They were randomly allocated into 3 groups: control group (n=64, including 15 cows where the follicle failed to rupture by light digital pressure), dominant follicle ablation on day 7 (n=57) and dominant follicle ablation on day 8 (n=46). Superstimulatory treatments started on day 10 for control or 1 day after ablation. Superovulation was induced by 9 im injections of decreasing dosage of gonadotrophins at 12-hour intervals over 4.5 days. PGF2α was administered in 2 im injections at the time of the seventh and the eighth injections of gonadotrophins. All females were artificially inseminated with frozen-thawed semen. Seven days after estrus embryos/ova were recovered by flushing the uterine horns, classified for stage and quality according to the IETS guidelines, and transferred fresh or frozen. Treated cows were subsequently monitored for adverse effects that could affect reproductive parameters or reproductive culling rate at 270 days post-partum. Total numbers of recovered structures and transferable embryos were lower (P0.05) among groups in mean grade of transferable embryos, but percentage of Grade-I embryos were higher in ablation 8 group (47.3%) than in control (37.9%), whereas Grade-II embryos were lower in ablation 8 group (37.5%) compared to control (45.6%) (P0.05). In conclusion, improvements in embryo number and quality were achieved by manually ablating the dominant ovarian follicle on days 7 or 8. Furthermore, there was no evidence that judicious manual ablation could have any detrimental effect on subsequent reproductive performance and culling rate.

A bent lithium niobate strip was exposed to a 400-GeV/c proton beam at the external lines of CERN Super Proton Synchrotron to probe its capabilities versus coherent interactions of the particles with the crystal such as channeling and volume reflection. Lithium niobate (LiNbO3) exhibits an interplanar electric field comparable to that of Silicon (Si) and remarkable piezoelectric properties, which could be exploited for the realization of piezo-actuated devices for the control of high-energy particle beams. In contrast to Si and germanium (Ge), LiNbO3 shows an intriguing effect; in spite of a low channeling efficiency (3%), the volume reflection maintains a high deflection efficiency (83%). Such discrepancy was ascribed to the high concentration (10(4) per cm2) of dislocations in our sample, which was obtained from a commercial wafer. Indeed, it has been theoretically shown that a channeling efficiency comparable with that of Si or Ge would be attained with a crystal at low defect concentration (less than ten per cm2). To better understand the role of dislocations on volume reflection, we have worked out computer simulation via dynecharm++ Monte Carlo code to study the effect of dislocations on volume reflection. The results of the simulations agree with experimental records, demonstrating that volume reflection is more robust than channeling in the presence of dislocations.

We have previously developed quinolone-3-carboxamides with the aim of obtaining new ligands for both cannabinoid receptors, CB1 and CB2. Our preliminary screening led to the identification of cannabinoid receptor ligands characterized by high affinity and, in some cases, also selectivity for CB(2) receptors. Specifically, three compounds, 1, 2 and 3 showed high affinity for CB2 as well as high selectivity over CB1 receptors. In addition, the activity shown by 1 against the formalin-induced nocifensive response in mice, reported in our previous paper, suggests that quinolone-3-carboxamides possess anti-nociceptive properties. In the present work, we have performed functional in vitro bioassays with the aim of investigating the functional activity in the [35S]GTPgammaS binding assay of the other two compounds that, like 1, behave as CB2 selective ligands, and their potential analgesic actions in vivo. We found that both 2 and 3 behave in vitro as CB2 inverse agonists and are able to decrease nociceptive behaviour in the late phase of the formalin test only at the highest dose tested, although, at lower doses, they prevent the anti-nociceptive effects of a selective CB2 partial agonist in the formalin test. These results identify in 2 and 3 two novel, potent and selective CB2 antagonists/inverse agonists and confirm previous reports in the literature that, in addition to agonists at cannabinoid CB2 receptors, also inverse agonists/antagonists at these receptors show promise as anti-inflammatory agents.

This summary is a project of the Institute for Community Engaged Scholarship (ICES) at the University of Guelph, with project partners: the Catalyst Centre, SPARK Program at the University of Guelph, and Knowledge Mobilization Unit at York University. This project is part of the Pan-Canadian Research Impact Network. http://csahs.uoguelph.ca/pps/Clear_Research Cannabidiol suppressed drug-induced vomiting in shrews and nausea-associated behaviours in rats. This effect was reversed, however, if the rodents were also given chemicals that blocked serotonin receptors in a part of the brainstem. Cannabidiol may help naturally produced serotonin activate these receptors more effectively. Project support by Agri-Food and Rural Link, Mobilizing Agri-food and Rural Research Knowledge. A program of the OMAFRA-U of G Partnership. http://www.uoguelph.ca/research/omafra/ partnership/KTT_and_IP.shtml

We study the possibility to use Single Photon Avalanche Diodes (SPAD) as photodetectors for applications in space missions. SPADs are silicon devices operated above the junction breakdown voltage (with the typical overvoltage of 5V), for which a single photon interacting in the active region is sufficient to trigger a self-sustainable avalanche discharge. SPADs can thus be used for the detection of very low light levels with a fast time response around 50ps FWHM for single photon detection, without spectroscopic capabilities. Large area SPAD (500 µm in diameter) have been designed and fabricated at the CNR-IMM facility, with an intrinsic noise lower than 10kHz at -15°C, before irradiation. We performed bulk damage radiation tests with protons in order to evaluate their radiation hardness properties and their suitability for application in a Low Earth Orbit (LEO) space mission. With this aim SPAD devices have been irradiated up to 3×109 (28.5 MeV) p/cm2. The test performed show that large area SPAD are very sensitive to proton doses as low as 1×108 p/cm2 with a significant increase in dark counts rate as well as in the manifestation of the "random telegraph signal" effect. Lower protons doses in the range 1-5×107 p/cm2 result in a lower increase of DCR suggesting that applicability in low-inclination LEO, particularly useful for gamma-ray astrophysics, is still feasible.

We study the possibility to use Single Photon Avalanche Diodes (SPADs) optically coupled to scintillating fibers as a novel type of gamma-ray detector for space applications. SPADs are silicon devices operating under polarization conditions above the junction breakdown voltage (typical overvoltage of 5V), for which a single photon interacting in the active region is sufficient to trigger a self sustainable avalanche discharge. SPADs can thus be used for the detection of very low light levels with an absolute timing accuracy of about 30 ps for single photon detection, without spectroscopic capabilities. In this presentation we report the preliminary results on large area SPAD (actual results refers to SPADs having 200 ?m diameter, with the aim to grow up to 500 ?m SPADs) coupled to scintillating fibers as the basic module for a particle tracker for space application. Dark counts rate as low as few tens of kHz at room temperature, lowering down to few kHz at -10°C have been obtained for the 200 ?m devices, in accordance with the basic requirements for the proposed application. Similar instruments based on silicon photomultiplier (SiPM) readout have already been studied, but none based on SPAD has been realized up to now. Moreover, since very few information is available on SPADs for the use in a space environment, we performed bulk damage and total dose radiation tests with protons and gamma-rays in order to evaluate their radiation hardness properties and their suitability for application in a Low Earth Orbit (LEO) space mission. With this aim the SPAD devices have be irradiated using up to 20 krad total dose with gamma-rays and 5 krad with protons