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Source-bonding as a Variable in Electroacoustic Composition: Faktura and Acoustics in Understatements
Understatements for two-channel fixed media is a four-movement study of the sonic potential of acoustic instruments within the practice of electroacoustic studio composition. The musical identity of the entire composition is achieved through consistent approaches to disparate instrumental materials and a focused investigation of the relationships between the various acoustic timbres and their electroacoustic treatments. The analytical section of this paper builds on contemporary research in electroacoustic arts. The analysis of the work is preceded by a summary of theoretical and aesthetic approaches within electroacoustic composition and the introduction of primary criteria of sonic faktura (material essence) used in the compositional process. The analyses address the idiosyncratic use of the concept of faktura to contextualize and guide the unfolding of the work. The reconciliation of the illusory electronic textures and the acoustic sources that parented them may be considered the ultimate goal of Understatements
Transverse localization and slow propagation of light
The effect of finite control beam on the transverse spatial profile of the
slow light propagation in an electromagnetically induced transparency medium is
studied. We arrive at a general criterion in terms of eigenequation, and
demonstrate the existence of a set of localized, stationary transverse modes
for the negative detuning of the probe signal field. Each of these
diffraction-free transverse modes has its own characteristic group velocity,
smaller than the conventional theoretical result without considering the
transverse spatial effect
Electromagnetically induced transparency in rubidium vapor prepared by a comb of short optical pulses
Journals published by the American Physical Society can be found at http://publish.aps.org/It was shown by Kocharovskaya and Khanin [Sov. Phys. JETP 63, 945 (1986)] that a comb of optical pulses can induce a ground-state atomic coherence and change the optical response of an atomic medium. In our experiment, we studied the propagation of a comb of optical pulses produced by a mode-locked diode laser in rubidium atomic vapor. Electromagnetically induced transparency (EIT) was observed when the pulse repetition rate is a subharmonic of the hyperfine splitting of the ground state. The width of the EIT resonance is determined by the relaxation rate of the ground-state coherence. Possible applications to magnetometery, atomic clocks, and frequency chains are discussed
Enhancement of field generation via maximal atomic coherence prepared by fast adiabatic passage in Rb vapor
We have experimentally demonstrated the enhancement of coherent Raman
scattering in Rb atomic vapor by exciting atomic coherence with fractional
stimulated Raman adiabatic passage. Experimental results are in good agreement
with numerical simulations. The results support the possibility of increasing
the sensitivity of CARS by preparing atomic or molecular coherence using short
pulses
Why the two-pulse photon echo is not a good quantum memory protocol
We consider in this paper a two-pulse photon echo sequence as a potential
quantum light storage protocol. It is widely believed that a two-pulse scheme
should lead to very low efficiency and is then not relevant for this specific
application. We show experimentally by using a Tm:YAG crystal that
such a protocol is on contrary very efficient and even too efficient to be
considered as a good quantum storage protocol. Our experimental work allows us
to point out on one side the real limitations of this scheme and on the other
side its benefits which can be a source of inspiration to conceive more
promising procedures with rare-earth ion doped crystals
Quantum Thermodynamic Cycles and quantum heat engines
In order to describe quantum heat engines, here we systematically study
isothermal and isochoric processes for quantum thermodynamic cycles. Based on
these results the quantum versions of both the Carnot heat engine and the Otto
heat engine are defined without ambiguities. We also study the properties of
quantum Carnot and Otto heat engines in comparison with their classical
counterparts. Relations and mappings between these two quantum heat engines are
also investigated by considering their respective quantum thermodynamic
processes. In addition, we discuss the role of Maxwell's demon in quantum
thermodynamic cycles. We find that there is no violation of the second law,
even in the existence of such a demon, when the demon is included correctly as
part of the working substance of the heat engine.Comment: 17 pages, 9 figures, 4 table
Coherent Excitation of a Two-Level Atom driven by a far off-resonant Classical Field: Analytical Solutions
We present an analytical treatment of coherent excitation of a Two-Level Atom
driven by a far-off resonant classical field. A class of pulse envelope is
obtained for which this problem is exactly solvable. The solutions are given in
terms of Heun function which is a generalization of the Hypergeometric
function. The degeneracy of Heun to Hypergeometric equation can give all the
exactly solvable pulse shapes of Gauss Hypergeometric form, from the
generalized pulse shape obtained here. We discuss the application of the
results obtained to the generation of XUV.Comment: 9 Pages, 8 Figures. Accepted for Physical Review A as a regular
articl
Experimental observation of vibrations produced by pulsed laser beam in MgO:57Fe
We report the first observation of a laser-produced vibration with the aid of Mössbauer techniques. Thin platelets of MgO single crystals were doped by diffusion of 57Fe atoms. The illumination of the MgO: 57Fe sample with a pulsed Nd:YAG laser produced a significant broadening of the Mössbauer spectrum. In order to find out what caused these changes, we performed a series of time-domain experiments, in which the Mössbauer spectra were collected only during a 2.5 μs gate interval. This gate interval was swept from 5 μs to 190 μs over the time interval between the two laser pulses. After laser irradiation, the position of the Mössbauer line was found to be changing in time as a decaying oscillations of well-defined frequency, which can be due to the vibration of the sample induced by the laser pulse. © 2006 Springer Science+Business Media, Inc
Suppression of γ-photon absorption via quantum interference
We show that the interference effects (similar to electromagnetically induced transparency, which was widely studied earlier in electronic transitions in optics) may appear in -radiation at nuclear transitions under the condition of nuclear level anticrossing. We demonstrate it also experimentally in optically thin samples of FeCO3
Флуоресцентная диагностика с хлорином е6 в хирургии глиом низкой степени злокачественности
Intraoperative fluorescence diagnostics of high-grade gliomas is widely used in neurosurgical practice. This work analyzes the possibilities of fluorescence diagnostics for low-grade gliomas (LGG) using chlorin e6 photosensitizer. The study included patients with newly diagnosed LGG, for whom chlorin e6 was used for intraoperative fluorescence control at a dose of 1 mg/kg. During the operation, the fluorescence intensity of various areas of the putative tumor tissue was analyzed using the RSS Cam – Endo 1.4.313 software. Tissue samples with various degrees of fluorescence intensity were compared with the results of their histopathological analysis (WHO tumor diagnosis, Ki-67 index, P53, VEGF). Fluorescence was detected in more than half of the cases, but in most cases had a focal character and low fluorescence intensity. The fluorescence intensity directly correlated with the data of histopathological examination of tumor tissues (Ki-67 index (p=0.002), expression of P53 (p=0.0015) and VEGF (p=0.001)). The sensitivity of the method for LGG surgery was 72%, the specificity was 56,7%. Intraoperative fluorescence diagnostics with chlorin e6 can be used in LGG surgery, especially to visualize intratumoral areas with a higher degree of anaplasia.Применение интраоперационной флуоресцентной диагностики для глиом высокой степени злокачественности широко используется в нейрохирургической практике. В работе проанализированы возможности флуоресцентной диагностики для глиом низкой степени злокачественности с использованием хлорина е6. В исследование были включены пациенты с впервые диагностированной глиомой низкой степени злокачественности (low-grade glioma, LGG), у которых с целью интраоперационного флуоресцентного контроля применен препарат хлорин е6 в дозе 1 мг/кг массы тела. В процессе операции анализировали интенсивность флуоресценции различных участков предполагаемой опухолевой ткани с использованием программного обеспечения RSS Cam – Endo 1.4.313. Образцы тканей различной степени интенсивности флуоресценции сопоставляли с результатами их гистопатологического анализа (диагностика опухоли ВОЗ, индекс Ki-67, P53, VEGF). Флуоресценция выявлена в более чем половине случаев, но в большинстве случаев имела очаговый характер и низкую интенсивность флуоресценции. Интенсивность флуоресценции напрямую коррелировала с данными гистопатологического исследования тканей опухоли: индекс Ki-67 (p=0,002), экспрессия P53 (p=0,0015), VEGF (p=0,001). Чувствительность метода для хирургии LGG составила 72%, специфичность 56,7%. Проведенное исследование подтвердило, что технология интраоперационной флуоресцентной диагностики с применением хлорина е6 может применяться в хирургии LGG, особенно для визуализации внутриопухолевых участков с более высокой степенью анаплазии
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