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101.
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103.
M. Jonker F. Udo J. V. Allaby U. Amaldi G. Barbiellini A. Capone W. Flegel M. Metcalf J. Meyer F. L. Navarria J. Panman A. M. Wetherell K. Winter F. W. Büsser H. Daumann P. D. Gall E. Metz F. Niebergall K. H. Ranitzsch P. Stähelin E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov A. Baroncelli B. Borgia C. Bosio F. Ferroni E. Longo P. Monacelli F. de Notaristefani P. Pistilli C. Santoni V. Valente 《Zeitschrift fur Physik C Particles and Fields》1983,17(3):211-217
The question whether scalar-type interactions contribute to weak interactions at large momentum transfer has been investigated by a measurement of the longitudinal polarization of positive muons produced in charged-current interactions of high-energy antineutrinos with iron. At an average momentum transfer <Q 2>=4 GeV2 the muon spin is found to be oriented forward with respect to the muon momentum vector, with an average polarization of 1.10±0.24, consistent with positive helicity. A limit on scalar contributions of σs, p/σtot <7% at the 95% confidence level can be deduced. A search for violation of time reversal invariance which could manifest itself by a polarization component perpendicular to the muon production plane gave a limit of σtv/σtot <16% (95% c.l.). It is concluded that the weak leptonic charged current retains its dominant vector and axial vector structure at large momentum transfers. 相似文献
104.
A glycine receptor is involved in the organization of swimming movements in an invertebrate chordate
Background
Rhythmic motor patterns for locomotion in vertebrates are generated in spinal cord neural networks known as spinal Central Pattern Generators (CPGs). A key element in pattern generation is the role of glycinergic synaptic transmission by interneurons that cross the cord midline and inhibit contralaterally-located excitatory neurons. The glycinergic inhibitory drive permits alternating and precisely timed motor output during locomotion such as walking or swimming. To understand better the evolution of this system we examined the physiology of the neural network controlling swimming in an invertebrate chordate relative of vertebrates, the ascidian larva Ciona intestinalis. 相似文献105.
We show experimentally that large matrices of localized structures can be stored as elementary pixels in a nematic liquid crystal cell. Based on optical feedback with phase modulated input beam, our system allows us to store, erase, and actualize the localized structures in the matrix. 相似文献
106.
Ricciardi A Pisco M Gallina I Campopiano S Galdi V O' Faolain L Krauss TF Cusano A 《Optics letters》2010,35(23):3946-3948
We report on the first experimental evidence of guided resonances (GRs) in photonic crystal slabs based on aperiodically ordered supercells. Using Ammann-Beenker (quasiperiodic, eightfold symmetric) tiling geometry, we present our study on the fabrication, experimental characterization, and full-wave numerical simulation of two representative structures (with different filling parameters) operating at near-IR wavelengths (1300-1600 nm). Our results show a fairly good agreement between measurements and numerical predictions and pave the way for the development of new strategies (based on, e.g., the lattice symmetry breaking) for GR engineering. 相似文献
107.
Stefania Bellavia Elisa Riccietti 《Journal of Optimization Theory and Applications》2018,178(3):824-859
In this paper, we address the stable numerical solution of ill-posed nonlinear least-squares problems with small residual. We propose an elliptical trust-region reformulation of a Levenberg–Marquardt procedure. Thanks to an appropriate choice of the trust-region radius, the proposed procedure guarantees an automatic choice of the free regularization parameters that, together with a suitable stopping criterion, ensures regularizing properties to the method. Specifically, the proposed procedure generates a sequence that even in case of noisy data has the potential to approach a solution of the unperturbed problem. The case of constrained problems is considered, too. The effectiveness of the procedure is shown on several examples of ill-posed least-squares problems. 相似文献
108.
Michelangelo Iannone Stefania Bulotta Donatella Paolino Maria Cristina Zito Santo Gratteri Francesco S Costanzo Domenicantonio Rotiroti 《BMC neuroscience》2006,7(1):13-6
Background
3,4-Methylenedioxymethamphetamine (MDMA; ecstasy) is known for its toxicological, psychopathological and abuse potential. Some environmental conditions, e.g. acoustic stimulation typical of the "rave scene" can influence the toxicity of this drug. 相似文献109.
Stefania‐Felicia Barbuceanu Gabriela Bancescu Gabriel Saramet Florica Barbuceanu Constantin Draghici Flavian Stefan Radulescu Aura Ionescu Simona Negres 《Heteroatom Chemistry》2013,24(4):309-321
In the present study, new 1,2,4‐triazoles, 1,3,4‐thiadiazoles, and acylthiosemicarbaz‐ides derived from 4‐(4‐chlorophenylsulfonyl)benzoic acid hydrazide were synthesized and screened for their antimicrobial and analgesic activities. Acylthiosemicarbazides 2–4 were synthesized by a reaction of 4‐(4‐chlorophenyl‐sulfonyl)benzoic acid hydrazide 1 with different arylisothiocyanates.4,5‐Disubstituted‐2,4‐dihydro‐3H‐1,2,4‐triazol‐3‐thiones 5–7 and 2,5‐disubstituted‐1,3,4‐thiadiazoles 8–10 were obtained by dehydrative cyclization of corresponding acylthiosemicarbazide derivatives 2–4 in basic media (8% aqueous sodium hydroxide) and in acidic media (sulfuric acid or phosphorous oxychloride), respectively. The structures of the newly synthesized compounds have been confirmed on the basis of elemental analysis and spectral studies (IR, 1H NMR, 13C NMR, MS). Their antimicrobial activities against some bacteria and yeasts were investigated. The analgesic activity of all compounds was performed with two pharmacological tests: the writhing test induced with acetic acid and hot‐plate test. The results showed that triazole 7 had the best antimicrobial activity against Bacillus cereus. In the chemical stimulus test, triazoles 6 and 7 were the most active compounds whereas in the hot‐plate test thiadiazoles 9 and 10 exhibited the highest analgesic activity. 相似文献
110.
In the last few years, the concepts of stability and Clifford regularity have been fruitfully extended by using star operations. In this article we deepen the study of star stable and star regular domains and relate these two classes of domains to each other. 相似文献