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101.
Uncovering the physics of electroweak symmetry breaking (EWSB) is the raison-d’etre of the LHC. Flavor questions, it would seem, are of minor relevance for this quest, apart from their role in constraining the possible structure of EWSB physics. In this short review article, we outline, using flavor-dependent slepton physics as an example, how flavor can affect both searches for supersymmetry, and future measurements aimed at understanding the nature of any new discoveries. If the production cross-sections for supersymmetry are relatively low, as indicated by the fact that it has not revealed itself yet in standard searches, the usual assumptions about the superpartner spectra need rethinking. Furthermore, one must consider more intricate searches, such as lepton-based searches, which could be susceptible to flavor effects. We start by reviewing the flavor structure of existing frameworks for mediating supersymmetry breaking, emphasizing flavor-dependent models proposed recently. We use the kinematic endpoints of invariant mass distributions to demonstrate how flavor dependence can impact both searches for supersymmetry and the Inverse Problem. We also discuss methods for measuring small-mass splittings and mixings at the LHC, both in models with a neutralino LSP and in models with a charged slepton (N)LSP. 相似文献
102.
Remez RE Dubowski KR Davids ML Thomas EF Paddu NU Grossman YS Moskalenko M 《The Journal of the Acoustical Society of America》2011,130(4):2173-2178
Linear prediction is a widely available technique for analyzing acoustic properties of speech, although this method is known to be error-prone. New tests assessed the adequacy of linear prediction estimates by using this method to derive synthesis parameters and testing the intelligibility of the synthetic speech that results. Matched sets of sine-wave sentences were created, one set using uncorrected linear prediction estimates of natural sentences, the other using estimates made by hand. Phoneme restrictions imposed on linguistic properties allowed comparisons between continuous and intermittent voicing, oral or nasal and fricative manner, and unrestricted phonemic variation. Intelligibility tests revealed uniformly good performance with sentences created by hand-estimation and a minimal decrease in intelligibility with estimation by linear prediction due to manner variation with continuous voicing. Poorer performance was observed when linear prediction estimates were used to produce synthetic versions of phonemically unrestricted sentences, but no similar decline was observed with synthetic sentences produced by hand estimation. The results show a substantial intelligibility cost of reliance on uncorrected linear prediction estimates when phonemic variation approaches natural incidence. 相似文献
103.
We present the first quantitative measurements of shape and energy variation in non-Euclidean plates. Using environmentally responsive gel, we construct non-Euclidean disks of constant imposed Gaussian curvature, K(tar). We vary the disks' thickness t(0) and measure the dependence of configurations, surface curvature, and energy content on t(0). For K(tar)<0, configurations are of a single wavy mode and undergo a set of bifurcations that leads to their refinement with decreasing thickness. This leads to sharp increase in the amount of surface bending as t(0)→0, and to a slow decay of both bending and stretching energies. Both vary like t(0)(2), compared with t(0)(3) of the bending energy in disks with K(tar)>0. 相似文献
104.
Yael Ben-Haim 《Journal of Combinatorial Theory, Series A》2008,115(7):1114-1126
An adaptive version of identifying codes is introduced. These codes are motivated by various engineering applications. Bounds on adaptive identifying codes are given for regular graphs and torii in the square grid. The new codes are compared to the classical non-adaptive case. 相似文献
105.
A novel approach was developed to form engineered, electrically viable, neuronal networks, consisting of ganglion-like clusters of neurons. In the present method, the clusters are formed as the cells migrate on low affinity substrate towards high affinity, lithographically defined carbon nanotube templates on which they adhere and assemble. Subsequently, the gangliated neurons send neurites to form interconnected networks with pre-designed geometry and graph connectivity. This process is distinct from previously reported formation of clusterized neural networks in which a network of linked neurons collapses via neuronal migration along the inter-neuron links. The template preparation method is based on photo-lithography, micro-contact printing and carbon nanotube chemical vapor deposition techniques. The present work provides a new approach to form complex, engineered, interconnected neuronal network with pre-designed geometry via engineering the self-assembly process of neurons. 相似文献
106.
Bransky Avishay Korin Natanel Leshansky Alexander Lanir Naomi Nemirovski Yael Dinnar Uri 《Rheologica Acta》2007,46(5):621-627
Red blood cells (RBCs) suspended in a high-viscosity medium were filmed while flowing through a microchannel using an automated
rheoscope. Under these conditions, erythrocytes take different orientations and undergo varying deformation according to their
location in the velocity profile. Measurements of the mean deformation at several distances from the center of the microchannel
at a constant flow rate were acquired for normal and thalassemia erythrocytes. The measurements demonstrate how diagnosis
can be made based on a single flow rate in contrast to conventional methods where shear is mechanically controlled. The spatial
distribution and velocity of RBCs and rigid microspheres (1 μm) were measured. The maximum slip velocity was found to be linearly
correlated to the flow rate for both cells and microspheres. RBCs showed enhanced inward lateral migration compared to the
rigid spheres, which is attributed to RBC deformation. The results demonstrate the coupling between RBC mechanical properties
and their motion in microvessels.
This paper was presented at Annual European Rheology Conference (AERC) held in Hersonisos, Crete, Greece, April 27-29, 2006. 相似文献
107.
We initiate a systematic study of eigenvectors of random graphs. Whereas much is known about eigenvalues of graphs and how they reflect properties of the underlying graph, relatively little is known about the corresponding eigenvectors. Our main focus in this article is on the nodal domains associated with the different eigenfunctions. In the analogous realm of Laplacians of Riemannian manifolds, nodal domains have been the subject of intensive research for well over a hundred years. Graphical nodal domains turn out to have interesting and unexpected properties. Our main theorem asserts that there is a constant c such that for almost every graph G, each eigenfunction of G has at most two large nodal domains, and in addition at most c exceptional vertices outside these primary domains. We also discuss variations of these questions and briefly report on some numerical experiments which, in particular, suggest that almost surely there are just two nodal domains and no exceptional vertices. © 2010 Wiley Periodicals, Inc. Random Struct. Alg., 39, 39–58, 2011 相似文献
108.
Bat-El Oded Yael Diskin-Posner Dr. Vered Marks Prof. Haya Kornweitz Prof. Flavio Grynszpan 《European journal of organic chemistry》2023,26(39):e202300697
Theoretical and experimental mixed approaches are complementary and valuable. Our DFT calculations support the mechanism suggested by Kosower, adding to it a key diaziridine intermediate that determines the relative product distribution of this reaction. Our results are consistent with the formation of the diazoketene intermediate as the rate-limiting step. Based on curve fittings, first or second-order kinetics cannot be ruled out. This may indicate that more than one mechanism is simultaneously at play in this transformation. This unexpected outcome led us to study an alternative cyclopropenone intermediate. Although cyclopropenone is not likely to be formed under thermal conditions, adding it to the reaction mixture results in bimane structures. The most staggering finding from this investigation was the unanticipated generation of the unsymmetrical anti-(Me,Me)(Ph,Ph)bimane. The optimization of this route towards unsymmetrical bimanes will require additional investigation. 相似文献
109.
Consisting of organically modified silica (ORMOSIL) physically doped with Ag nanoparticles, the SilverSil new class of antibacterial materials of broad scope reported herein shows remarkably high and stable activity against representative Gram-positive and Gram-negative bacteria. The low cost, ease of application and excellent health and environmental profile of SilverSil hybrid glassy coatings open the route to their widespread utilization across domestic, hospital, school, industrial and commercial environments and in consumer products. 相似文献
110.
Yael Dror Yachin Cohen Rachel Yerushalmi‐Rozen 《Journal of Polymer Science.Polymer Physics》2006,44(22):3265-3271
Gum arabic, a natural polysaccharide derived from exudates of Acacia senegal and Acacia seyal trees, is a commonly used food hydrocolloid. The complex chemical structure of the gum has been widely studied revealing a multifraction material consisting mainly of a highly branched polysaccharide and a protein–polysaccharide complex (GAGP) as a minor component. This work investigates its mesoscopic structure in aqueous solution by small‐angle X‐ray and neutron scattering combined with cryotransmission electrons microscopy. Scattering measurements reveal an intricate shape composed of many spheroidal aggregates assigned to the polysaccharide with a small amount of larger coils. A scattering peak is observed at moderate to high concentrations, the spacing of which exhibits a c?1/3 power law relation to polymer concentration (c). Upon addition of salt, this peak disappears, indicating its electrostatic nature. The large coils contribute a q?2 power law at the low scattering vector (q) range. However, at low concentration in which the interaggregate peak is not observed, a q?1 power law at the low q range indicates the possible existence of a fraction with a locally extended conformation. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3265–3271, 2006 相似文献