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A new version of the method for spatiotemporal smoothing of laser radiation using spectral dispersion is proposed, which does not require the use of high-frequency phase modulators, i.e. a method based on the use of a broadband master oscillator. An experimental study of this method has been conducted on the Luch laser facility.

Death-associated protein 1 (DAP1) is a proline-rich cytoplasmatic protein highly conserved in most eukaryotes. It has been reported to be involved in controlling cell growth and migration, autophagy and apoptosis. The presence of human DAP1 is associated to a favourable prognosis in different types of cancer. Here we describe the almost complete $${{^{1}}\text {H}}$$ 1 H , $${{^{13}}\text {C}}$$ 13 C , and $${{^{15}}\text {N}}$$ 15 N chemical shift assignments of the human DAP1. The limited spectral dispersion, mainly in the $${{^{1}}\text {H}{^{\text{N}}}}$$ 1 H N region, and the lack of defined secondary structure elements, predicted based on chemical shifts, identifies human DAP1 as an intrinsically disordered protein (IDP). This work lays the foundation for further structural investigations, dynamic studies, mapping of potential interaction partners or drug screening and development.

It is shown that the use of both sides of solar cells created with the heterojunction technology makes possible an increase in the solar-cell efficiency. The difference in illumination of the front and back sides is associated with transformation of the blue part of the spectrum, which is shown by the example of the spectral dispersion of the quantum efficiency. The average difference between the quantum efficiency for both sides is ~11%. The short-circuit current density with the power of the solar spectrum at sea level from 400 to 1100 nm is 36.3 mA/cm2 for the front side and 32.7 mA/cm2 for the back side. The decrease amounts to 9.7%.

In this study, the variability of the spectral dispersion of droplet size distributions (DSDs) in convective clouds is investigated. Analyses are based on aircraft measurements of growing cumuli near the Amazon basin, and on numerical simulations of an idealized ice‐free cumulus. In cleaner clouds, the relative dispersion ϵ, defined as the ratio of the standard deviation to the mean value of the droplet diameter, is negatively correlated with the ratio of the cloud water content (qc) to the adiabatic liquid water content (qa), while no strong correlation between ϵ and qc/qa is seen in polluted clouds. Bin microphysics numerical simulations suggest that these contrasting behaviors are associated with the effect of collision‐coalescence in cleaner clouds, and secondary droplet activation in polluted clouds, in addition to the turbulent mixing of parcels that experienced different paths within the cloud. Collision‐coalescence simultaneously broadens the DSDs and decreases qc, explaining the inverse relationship between ϵ and qc/qa in cleaner clouds. Secondary droplet activation broadens the DSDs but has little direct impact on qc. The combination of a rather modest DSD broadening due to weak collision‐coalescence with enhanced droplet activation in both diluted and highly undiluted cloud regions may contribute to maintain a relatively uniform ϵ within polluted clouds. These findings can be useful for parameterizing the shape parameter (μ) of gamma DSDs in bulk microphysics cloud‐resolving models. It is shown that emulating the observed μ−qc/qa relationship improves the estimation of the collision‐coalescence rate in bulk microphysics simulations compared to the bin simulations., Key Points: Droplet size distribution patterns observed in warm cumuli reflect the roles of collision‐coalescence, secondary activation, and mixing. The intra‐cloud distribution of droplet spectral dispersion varies with aerosol loading. Emulating the observed shape‐parameter improves bulk estimations of collision‐coalescence in models., Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) http://dx.doi.org/10.13039/501100001807, Max Planck Society (MPG), U.S. Department of Energy (DOE) http://dx.doi.org/10.13039/100000015, Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659, HALO

F-19 images have been obtained from perflurooctylbromide (PFOB) at very low magnetic field (50 mT). The small spectral dispersion (in Hz) means that all fluorine nuclei contribute to the signal without chemical shift artifacts or the need for specialized imaging sequences. Turbo spin echo trains with short interpulse intervals and full 180 degrees refocussing pulses suppress scalar coupling, leading to long apparent T-2 values and highly efficient data collection. Overall, the detection efficiency of PFOB is very similar that of water in tissue. (C) 2021 The Author(s). Published by Elsevier Inc.

The third major reprocessing campaign for the Orbiting Carbon Observatory 2 mission is underway. With each release, several aspects of instrument calibration were improved. An onboard lamp tracks relative gain degradation, but ages too quickly to track absolute scaling. The most significant changes between builds were evolving assumptions about the stability of the solar calibrator. For the newest build, the trend in lunar measurements over a 4.5-year time series was applied. Another significant change was to expand a list of detector outliers via review of dark, lamp, and science measurements. More subtle adjustments to stray light and spectral dispersion were also performed. The techniques developed for OCO-2 are being applied to the Orbiting Carbon Observatory 3, which completed in-orbit checkout in August 2019. OCO-3 does not have a solar calibrator, and will need to constrain lamp aging via secondary lamps and comparison to other satellites.

Five parameterizations of cloud droplet spectral shape are implemented in a global climate model to investigate the dispersion effect and aerosol indirect effect (AIE). We design a series of experiments by modifying the microphysical cloud scheme of NCAR CAM5.3 (National Center for Atmospheric Research Community Atmosphere Model Version 5.3). We employ four empirical (Martin94, RLiu03, PengL03, and Liu08) and one semi‐analytical (LiuLi15) expressions for cloud droplet spectral shape parameters. Analysis focuses on the instantaneous differences in the simulated cloud microphysical properties and the comparison between model output and satellite data. The results show that RLiu03, PengL03, and LiuLi15 produce wider droplet spectrum and faster autoconversion rate, but Liu08 has a narrower droplet spectrum and slower autoconversion rate than the default parameterization (Martin94) in CAM5.3. Global dispersion effects caused by the five parameterizations modify the aerosol indirect effect by −10% (counteract) to 13% (strengthen). The simulated AIEs and dispersion effects exhibit noticeably spatial inhomogeneity. In the sensitive regions of AIE (Southeast Asia, North Pacific, and West Coast of South America), we decompose the response of shortwave cloud forcing to the change in droplet number for analysis. The varying dispersion effects can be explained by different responses of cloud properties in different spectral parameterizations.

Optical smoothing techniques are widely used in large high-power laser facilities designed for inertial confinement fusion research, such as the Laser Mégajoule (LMJ) in France. Those techniques are of primordial interest because they reduce laser–plasma instabilities as, for example, the stimulated backward Brillouin scattering (SBS). The latter takes place in the hot plasmas produced inside a hohlraum by the ablation of high-Z or gold material where ion acoustic waves are weakly damped, easing SBS. However, despite the current optical smoothing implementation, like smoothing by spectral dispersion (SSD), SBS is not sufficiently mitigated and may also damage the laser optics by following back the laser path. Moreover, SSD limits the available energy and may produce unwanted amplitude modulations in the laser chain, resulting in an additional damage. Using spectral distribution with two colors (Duluc et al 2019 Phys. Rev. Appl. 12 054055) has proven to limit the latter damage, keeping the same efficiency for limiting SBS. In this study, we go a step forward and generalize this approach by exploring multi-color spectral distribution schemes and the role of dispersion by means of three-dimensional simulations. This study paves the road to new laser concepts that could tackle more efficiently the laser–plasma interaction issues leading to a better laser energy coupling.

(1)H nuclear magnetic resonance (NMR) spectroscopy-based metabolic phenotyping is now widely used for large-scale epidemiological applications. To minimize signal overlap present in 1D (1)H NMR spectra, we have investigated the use of 2D J-resolved (JRES) (1)H NMR spectroscopy for large-scale phenotyping studies. In particular, we have evaluated the use of the 1D projections of the 2D JRES spectra (pJRES), which provide single peaks for each of the J-coupled multiplets, using 705 human plasma samples from the FGENTCARD cohort. On the basis of the assessment of several objective analytical criteria (spectral dispersion, attenuation of macromolecular signals, cross-spectral correlation with GC-MS metabolites, analytical reproducibility and biomarker discovery potential), we concluded that the pJRES approach exhibits suitable properties for implementation in large-scale molecular epidemiology workflows.

Intrinsically disordered proteins (IDPs) are multi-conformational polypeptides that lack a single stable three-dimensional structure. It has become increasingly clear that the versatile IDPs play key roles in a multitude of biological processes, and, given their flexible nature, NMR is a leading method to investigate IDP behavior on the molecular level. Here we present an IDP-tailored J-modulated experiment designed to monitor changes in the conformational ensemble characteristic of IDPs by accurately measuring backbone one- and two-bond J(15N,13Cα) couplings. This concept was realized using a unidirectional (H)NCO 13C-detected experiment suitable for poor spectral dispersion and optimized for maximum coverage of amino acid types. To demonstrate the utility of this approach we applied it to the disordered actin-binding N-terminal domain of WASp interacting protein (WIP), a ubiquitous key modulator of cytoskeletal changes in a range of biological systems. One- and two-bond J(15N,13Cα) couplings were acquired for WIP residues 2–65 at various temperatures, and in denaturing and crowding environments. Under native conditions fitted J-couplings identified in the WIP conformational ensemble a propensity for extended conformation at residues 16–23 and 45–60, and a helical tendency at residues 28–42. These findings are consistent with a previous study of the based upon chemical shift and RDC data and confirm that the WIP2–65 conformational ensemble is biased towards the structure assumed by this fragment in its actin-bound form. The effects of environmental changes upon this ensemble were readily apparent in the J-coupling data, which reflected a significant decrease in structural propensity at higher temperatures, in the presence of 8 M urea, and under the influence of a bacterial cell lysate. The latter suggests that crowding can cause protein unfolding through protein–protein interactions that stabilize the unfolded state. We conclude that J-couplings are a useful measureable in characterizing structural ensembles in IDPs, and that the proposed experiment provides a practical method for accurately performing such measurements, once again emphasizing the power of NMR in studying IDP behavior.

Conditional spectral dispersion ( CSD) is a measure of response spectrum variability that implicitly characterizes the variety of spectral shapes within a suite of ground motions. It is used here to explain the discrepancy between median structural demands estimated from different suites of scaled and spectrum-matched ground motions. Performing response history analyses with spectrum-matched ground motions is known to result in unconservatively biased median demand estimates in some cases. Herein, several suites of scaled ground motions with equivalent median intensities and varying levels of CSD are selected. A single suite of spectrum-matched ground motions is also created. These records are used to analyze the responses of inelastic single-degree-of-freedom and first-mode-dominated multiple-degree-of-freedom structural systems. Collapse capacities are also examined. A consistent trend between CSD and resulting median responses indicates that the bias phenomenon can be fully explained by an asymmetric relationship between conditional spectral ordinates at periods affecting inelastic response.

The relation between the effective ordinary refractive index n* = (n o n e )1/2 of a quasi-two-dimensional polydomain uniaxial film of a conjugated polymer F8BT in the visible transparency region and the refractive indices (n o,e ) of uniaxial domains with the optical axes randomly oriented in the plane of the film has been confirmed experimentally. The permissible interval of variations in n* has been established and a strong spectral dispersion of this interval near the long-wavelength electronic absorption band of the film has been demonstrated.

Frequency doubling of an infrared laser radiation in non-linear optical crystals is a widely used technique to obtain light in the visible range. The second harmonic generation process is influenced by several well-known parameters. In this article we study the effect of group delay dispersion on the second harmonic generation process for femtosecond pulses. We show, both through simulation and experiments, that for certain parameters even a small amount of chirp can have a detrimental effect on the conversion efficiency as well as the second harmonic beam quality. We also check the effect of higher order dispersion. By properly accounting for those effects the crystal length and focusing conditions can be optimized to reach high conversion efficiency, while maintaining low sensitivity to chirp variations and good beam quality.

The most common devices for the spectral dispersion of light are prism and grating spectrometers as well as diverse types of interferometers such as Fabry-Perot, Fizeau or Michelson interferometers.

We propose and demonstrate a scheme for second-harmonic generations with ultra-broad acceptance bandwidth and flat-top spectrum shape by using quasi-phase-matching modified fan-out periodically poled crystals with transversely varying grating length, in combination with spatial spectral dispersion of fundamental pulses. It is shown that, theoretically, the scheme has the capability of broadening the bandwidth and tailoring the spectrum shape of the second-harmonic arbitrarily, by appropriately patterning the transverse variation of grating period and length.

Resumo : Neste ensaio, temos como proposito realizar uma terapia de dispersao espectral do noturno a partir do filme War Requiem , do diretor britânico Derek Jarman, tendo como principal referencia o estilo terapeutico de filosofar acionado por Ludwig Wittgenstein em suas Investigacoes Filosoficas . Uma terapia de dispersao espectral do noturno - tal como a temos denominado e praticado a partir de outras tematicas no campo dos Estudos Literarios – parte de efeitos de sentido de noturno, sugeridos por cenas do referido filme, sobre o corpo de um espectador-terapeuta, e investiga semelhancas de familia entre esses efeitos e aqueles que se manifestam em outros jogos de linguagem, nao necessariamente filmicos, que tambem encenam e significam o noturno de outras maneiras. Palavras-chave : War Requiem; Derek Jarman; terapia de dispersao espectral do noturno. Abstract : In this essay, our purpose is to perform a spectral dispersion therapy of the nocturne from the War Requiem film by British director Derek Jarman. For this, we will take as main reference the therapeutic style of philosophizing practiced by Ludwig Wittgenstein in his Philosophical Investigations . A spectral dispersion therapy of the nocturne - as we have called and practiced it from other themes in the field of Literary Studies - starts of meaning effects of the nocturne, suggested by some scenes of that movie, on the body of a spectator-therapist, in order to investigate family resemblances between these effects and those that manifest themselves in other language games which also stage and mean the nocturne in other ways. Keywords : War Requiem ; Derek Jarman; Spectral dispersion therapy of the nocturne.

We fabricated and characterized a pair of ultrabroadband chirped mirrors (CMs) in the infrared. These mirrors provide smooth control of the spectral phases in the wavelength range 1200–2200 nm, nearly one octave of a bandwidth. A scanning-type white-light Michelson interferometer was developed to measure spectral dispersion. We confirmed that the dispersion of the CMs well reproduced the designed dispersion. Furthermore, the CMs’ damage threshold was measured to be $${>}390\,\hbox {mJ}/\hbox {cm}^2$$ for 10-fs pulses, which corresponds to $${>}37\,\hbox {TW}/\hbox {cm}^2$$ .

Skin wrinkles are visually perceived by consumers but they are also known to possess an underlying structure not apparent at the surface of the skin. This underlying structure can be brought out by polarized hyperspectral imaging. Wrinkle patterns of eye crow’s feet are used as example to show a deeper existing pattern and their characterization versus age on a group of volunteers. The skin inhomogeneity changes within each layer of the skin and can be observed in the shorter wavelength region of the spectrum, about 450nm to 500nm which are well suited to image skin surface inhomogeneities within the central and deep epidermis. Imaging in the 550nm range can serve as a larger scale topology reference because of its deeper penetration into the upper dermis. This serves to bring out the underlying wrinkle pattern as imprinted by collagen anisotropies around deep folds but unapparent to the eye yet. The approach has potential applications in evaluating the internal skin patterns non visible to the eye by mapping their spectral dispersion. This method has thus potentials to evaluate the extent of subsurface structures such as acne and other scars and thereby the efficacy of treatments.

NMR spectroscopy is one of the most powerful and versatile analytic tools available to chemists. The discrete Fourier transform (DFT) played a seminal role in the development of modern NMR, including the multidimensional methods that are essential for characterizing complex biomolecules. However, it suffers from well-known limitations: chiefly the difficulty in obtaining high-resolution spectral estimates from short data records. Because the time required to perform an experiment is proportional to the number of data samples, this problem imposes a sampling burden for multidimensional NMR experiments. At high magnetic field, where spectral dispersion is greatest, the problem becomes particularly acute. Consequently multidimensional NMR experiments that rely on the DFT must either sacrifice resolution in order to be completed in reasonable time or use inordinate amounts of time to achieve the potential resolution afforded by high-field magnets.Maximum entropy (MaxEnt) reconstruction is a non-Fourier method...

Magnetic resonance spectroscopy (MRS) provides information on neuronal and axonal viability, energetics of cellular structures, and status of cellular membranes. Proton MRS appeals to clinicians and scientists because its application in the clinical setting can increase the specificity of MR imaging. The objective of this article is to provide descriptive concepts of the technique and its application in vivo for a variety of patient populations. When appropriately incorporating MRS into the neuroradiologic evaluation, this technique produces relevant information to radiologists and clinicians for their understanding of adult and pediatric neurologically based disease processes.

The experimental performance of beam smoothing by combined one-dimensional (1D) spectral dispersion and lens array (LA) technology is presented, as applied in the ninth beam of SG-II. Using 3\omega spectral dispersion with a bandwidth of 270 GHz and a line dispersion that is 24.9 times the beam's diffraction-limited width decreases the focal spot non-uniformity of 80% energy concentration from 46% to 17%. The multiple-beam interference properties of the LA are theoretically and experimentally validated by spatial power spectral density analysis. Peak-spectra suppression ratios of 20 and 10 dB are achieved in the dispersion and orthogonal directions, respectively.

The effect of compensation for the spectral dispersion of light polarization states at the output of a single-domain layer of a chiral liquid crystal (CLC) is experimentally studied. It is shown that such dispersion can be decreased significantly with the aid of phase plates of two types that have different signs of the spectral dispersion of birefringence. The dispersion compensation allows one to significantly increase the operating spectral range of fast light modulators based on chiral nematic liquid crystals (NLCs).

A novel concept for octave spanning dispersive mirrors with low spectral dispersion oscillations is presented. The key element of the so-called wedge dispersive mirror is a slightly wedged layer which is coated on a specially optimized dispersive multilayer stack by a common sputter coating process. The group delay dispersion (GDD) of a pulse reflected on a wedge dispersive mirror is nearly free of oscillations. Fabricated mirrors with negative GDD demonstrate the compression of a pulse down to 3.8 fs as good as double angled mirrors optimized for the same bandwidth.

Metasurfaces as multi-ordered optical metatronic filters can be engineered using electronic circuit design procedures. Numerical examples with different functionality (low-pass, high-pass, band-pass, and band-stop) illustrate the ability of this procedure to synthesize optical frequency dispersion.

The high molecular weight and low concentration of brain glycogen render its noninvasive quantification challenging. Therefore, the precision increase of the quantification by localized (13) C MR at 9.4 to 14.1 T was investigated. Signal-to-noise ratio increased by 66%, slightly offset by a T(1) increase of 332 ± 15 to 521 ± 34 ms. Isotopic enrichment after long-term (13) C administration was comparable (≈ 40%) as was the nominal linewidth of glycogen C1 (≈ 50 Hz). Among the factors that contributed to the 66% observed increase in signal-to-noise ratio, the T(1) relaxation time impacted the effective signal-to-noise ratio by only 10% at a repetition time = 1 s. The signal-to-noise ratio increase together with the larger spectral dispersion at 14.1 T resulted in a better defined baseline, which allowed for more accurate fitting. Quantified glycogen concentrations were 5.8 ± 0.9 mM at 9.4 T and 6.0 ± 0.4 mM at 14.1 T; the decreased standard deviation demonstrates the compounded effect of increased magnetization and improved baseline on the precision of glycogen quantification.