364 research outputs found
High energy photon interactions at the LHC
Experimental prospects for studying high-energy photon-photon and
photon-proton interactions at the CERN Large Hadron Collider (LHC) are
discussed. Cross sections are calculated for many electroweak and beyond the
Standard Model processes. Selection strategies based on photon interaction
tagging techniques are studied. Assuming a typical LHC multipurpose detector,
various signals and their irreducible backgrounds are presented after applying
acceptance cuts. Prospects are discussed for the Higgs boson search, detection
of supersymmetric particles and of anomalous quartic gauge couplings, as well
as for the top quark physics.Comment: 17 pages, 16 tables and 14 figure
EFFECT OF SOME CHEMICAL MATERIAL AND GERMINATION MEDIA ON SEED GERMINATION AND GROWTH OF GRAFTED CASIMIROA TRANSPLANTS
This investigation was carried out in the plastic house of Horticulture Research Institute, Agriculture Research Center, Giza during two consequent seasons (2002 – 2003) and (2003 – 2004). The study was aimed to enhance growth of Casimiroa rootstock seedlings to reach grafting size in a short time, beside defineding the suitable method of grafting. In this concern, results revealed that seed soaked in MgSO4 at 5 % for 15 min. and planted in media consists of peat and sand at 1 : 1, was increased seed germination percentage (92.1 and 94.8 %) and minimized the germination period (19.1 and 19.3 days), as compared with the other treatments. Thus it reached to the grafting size at a period of (179 and 180 days) in both seasons, respectively. However, Dormex (hydrogen cyanamide) treatment at 2% gave the highest root length (24.6 and 24.8 cm), and number of roots per plant (19.4 and 19.0). Results also showed that shield budding by using soft wood grafts, gave the highest percentage of success (69.2 and 72.4%), shortest period of bud / scion (23.0 and 24.0 days), highest values of scion length (26.5 and 25.7 cm) and highest leaf area (38.28 and 40.67 cm2). However, cleft grafting with softwood grafts increased average number of leaves per sprouted graft (6.0 and 6.6) and shoot scion diameter (0.6 and 0.5 cm). Generally, seeds treated with MgSO4 at 5% berfore sowing in media consists of peat and sand at 1 : 1 in volume, induced healthy and sizeable rootstocks in a short time. Moreover, grafting rootstocks by soft wood grafts was the best method
THE TOOLS AND MONTE CARLO WORKING GROUP Summary Report from the Les Houches 2009 Workshop on TeV Colliders
This is the summary and introduction to the proceedings contributions for the
Les Houches 2009 "Tools and Monte Carlo" working group.Comment: 144 Pages. Workshop site
http://wwwlapp.in2p3.fr/conferences/LesHouches/Houches2009/ . Conveners were
Butterworth, Maltoni, Moortgat, Richardson, Schumann and Skand
Semantic Knowledge Influences Prewired Hedonic Responses to Odors
Background Odor hedonic perception relies on decoding the physicochemical properties of odorant molecules and can be influenced in humans by semantic knowledge. The effect of semantic knowledge on such prewired hedonic processing over the life span has remained unclear. Methodology/Principal Findings The present study measured hedonic response to odors in different age groups (children, teenagers, young adults, and seniors) and found that children and seniors, two age groups characterized by either low level of (children) or weak access to (seniors) odor semantic knowledge, processed odor hedonics more on the basis of their physicochemical properties. In contrast, in teenagers and young adults, who show better levels of semantic odor representation, the role of physicochemical properties was less marked. Conclusions/Significance These findings demonstrate for the first time that the biological determinants that make an odor pleasant or unpleasant are more powerful at either end of the life span
Effects of contrast material on computed tomographic measurements of lung volumes in patients with acute lung injury
BACKGROUND: Intravenous injection of contrast material is routinely performed in order to differentiate nonaerated lung parenchyma from pleural effusion in critically ill patients undergoing thoracic computed tomography (CT). The aim of the present study was to evaluate the effects of contrast material on CT measurement of lung volumes in 14 patients with acute lung injury. METHOD: A spiral thoracic CT scan, consisting of contiguous axial sections of 10 mm thickness, was performed from the apex to the diaphragm at end-expiration both before and 30 s (group 1; n = 7) or 15 min (group 2; n = 7) after injection of 80 ml contrast material. Volumes of gas and tissue, and volumic distribution of CT attenuations were measured before and after injection using specially designed software (Lungview(®); Institut National des Télécommunications, Evry, France). The maximal artifactual increase in lung tissue resulting from a hypothetical leakage within the lung of the 80 ml contrast material was calculated. RESULTS: Injection of contrast material significantly increased the apparent volume of lung tissue by 83 ± 57 ml in group 1 and 102 ± 80 ml in group 2, whereas the corresponding maximal artifactual increases in lung tissue were 42 ± 52 ml and 31 ± 18 ml. CONCLUSION: Because systematic injection of contrast material increases the amount of extravascular lung water in patients with acute lung injury, it seems prudent to avoid this procedure in critically ill patients undergoing a thoracic CT scan and to reserve its use for specific indications
Predicting Kindergarteners' End-Of-Year Spelling Ability Based On Their Reading, Alphabetic, Vocabulary, And Phonological Awareness Skills, As Well As Prior Literacy Experiences
This study examined the role of home literacy, parental education, and demographic factors in addition to conventional literacy skills at the beginning and end of kindergarten in predicting end-of-kindergarten spelling achievement. The study involved 9 schools and 29 classrooms serving an economically and ethnically diverse population (N = 288). Students spelled three types of words: sight words, decodable real words, and decodable pseudowords; spellings were scored to allow partial credit for invented spelling. Results from a three-step hierarchical regression indicated the variables accounted for 66% of the variance in spelling scores, with the single strongest spring predictor being a 1-minute letter-sound fluency test. Implications for instruction and for identifying students at risk for spelling and reading difficulties are discussed
Molecular complexity determines the number of olfactory notes and the pleasantness of smells
One major unresolved problem in olfaction research is to relate the percept to the molecular structure of stimuli. The present study examined this issue and showed for the first time a quantitative structure-odor relationship in which the more structurally complex a monomolecular odorant, the more numerous the olfactory notes it evokes. Low-complexity odorants were also rated as more aversive, reflecting the fact that low molecular complexity may serve as a warning cue for the olfactory system. Taken together, these findings suggest that molecular complexity provides a framework to explain the subjective experience of smells
- …