First-principles quantum calculations for anharmonic vibrational spectroscopy of three protected dipeptides are carried out and compared with experimental data. Using hybrid HF/MP2 potentials, the Vibrational Self-Consistent Field with Second-Order Perturbation Correction (VSCF-PT2) algorithm is used to compute the spectra without any ad hoc scaling or fitting. All of the vibrational modes (135 for the largest system) are treated quantum mechanically and anharmonically using full pair-wise coupling potentials to represent the interaction between different modes. In the hybrid potential scheme the MP2 method is used for the harmonic part of the potential and a modified HF method is used for the anharmonic part. The overall agreement between computed spectra and experiment is very good and reveals different signatures for different conformers. This study shows that first-principles spectroscopic calculations of good accuracy are possible for dipeptides hence it opens possibilities for determination of dipeptide conformer structures by comparison of spectroscopic calculations with experiment.
We clarify the sense in which the market outcome may be biased against preference minorities, and then estimate the degree of bias using an empirical model of entry into American radio broadcasting markets. Listening model estimates are used to infer fixed costs, and these estimates are then used to compute optimal station configurations as well as the welfare weights on different groups that rationalize the observed configuration. Welfare weights are 2-3 times higher for whites than for blacks, and 1.5-2 times higher for non-Hispanic than Hispanic, listeners. We explore the role of ’importing’ and ’exporting’ patterns in generating these findings.
D. Khazov, Yaron, O. , Gal-Yam, A. , Manulis, I. , Rubin, A. , Kulkarni, S. R, Arcavi, I. , Kasliwal, M. M, Ofek, E. O, Cao, Y. , Perley, D. , Sollerman, J. , Horesh, A. , Sullivan, M. , Filippenko, A. V, Nugent, P. E, Howell, D. A, Cenko, S. B, Silverman, J. M, Ebeling, H. , Taddia, F. , Johansson, J. , Laher, R. R, Surace, J. , Rebbapragada, U. D, Wozniak, P. R, ו Matheson, T.. 2016. “Flash Spectroscopy: Emission Lines From The Ionized Circumstellar Material Around ”. \Apj, 818, Pp. 3. doi:10.3847/0004-637X/818/1/3.
Mengdi Song, Pincemin, Erwan , Josten, Arne , Bäuerle, Benedikt , Hillerkuss, David , Leuthold, Juerg , Rudnick, Roy , Marom, Dan M. , Ben-Ezra, Shalva , Ferran, Jordi F. , Thouenon, Giles , Khodashenas, Pouria Sayyad , Rivas-Moscoso, José Manuel , Betoule, Christophe , Klonidis, Dimitrios , ו Tomkos, Ioannis . 2016. “Flexible Optical Cross-Connects For High Bit Rate Elastic Photonic Transport Networks”. Journal Of Optical Communications And Networking, 8, Pp. A126-A140. . Publisher's Versionתקציר
We present here the work performed in the EU-funded flexible optical cross-connect (FOX-C) project, which investigates and develops new flexible optical switching solutions with ultra-fine spectral granularity. Thanks to high spectral resolution filtering elements, the sub-channel content can be dropped from or added to a super-channel, offering high flexibility to optical transport networks through the fine adaptability of the network resources to the traffic demands. For the first time, the FOX-C solutions developed in the project are investigated here and evaluated experimentally. Their efficiency is demonstrated over two high spectral efficiency modulation schemes, namely multi-band orthogonal frequency division multiplexing (MB-OFDM) and Nyquist WDM (N-WDM) formats. Finally, in order to demonstrate the relevance of the FOX-C node concepts, a networking study comparing the economic advantages of the FOX-C optical aggregation solution versus the electronic one is performed.
Mengdi Song, Pincemin, Erwan , Josten, Arne , Bäuerle, Benedikt , Hillerkuss, David , Leuthold, Juerg , Rudnick, Roy , Marom, Dan M. , Ben-Ezra, Shalva , Ferran, Jordi F. , Thouenon, Giles , Khodashenas, Pouria Sayyad , Rivas-Moscoso, José Manuel , Betoule, Christophe , Klonidis, Dimitrios , ו Tomkos, Ioannis . 2016. “Flexible Optical Cross-Connects For High Bit Rate Elastic Photonic Transport Networks”. Journal Of Optical Communications And Networking, 8, 7, Pp. A126-A140. . Publisher's Versionתקציר
We present here the work performed in the EU-funded flexible optical cross-connect (FOX-C) project, which investigates and develops new flexible optical switching solutions with ultra-fine spectral granularity. Thanks to high spectral resolution filtering elements, the sub-channel content can be dropped from or added to a super-channel, offering high flexibility to optical transport networks through the fine adaptability of the network resources to the traffic demands. For the first time, the FOX-C solutions developed in the project are investigated here and evaluated experimentally. Their efficiency is demonstrated over two high spectral efficiency modulation schemes, namely multi-band orthogonal frequency division multiplexing (MB-OFDM) and Nyquist WDM (N-WDM) formats. Finally, in order to demonstrate the relevance of the FOX-C node concepts, a networking study comparing the economic advantages of the FOX-C optical aggregation solution versus the electronic one is performed.
This study examines effects of tides on fluctuations of the fresh-saline water interface and the groundwater level in unconfined coastal aquifers using a two-dimensional numerical model. The time-lags of the simulated hydraulic heads and salinities fluctuations compared to sea level fluctuations are analyzed using cross-correlation analysis. The results show that both the fresh-saline water interface and the groundwater level are affected harmonically by sea tide fluctuations. However, significantly different time-lags are obtained between the hydraulic head in the deeper and upper parts of the aquifer, and between head and salinity in the fresh-saline water interface. The hydraulic head in the deeper part of the aquifer responses much faster to sea level fluctuations than in the upper part. Surprisingly, a similar difference is detected between the time-lag of the hydraulic head in the fresh-saline water interface and the time-lag of the salinity at the same location. Furthermore, the time-lag of the salinity in the fresh-saline water interface is similar to the time-lag of the water table. We suggest a comprehensive mechanism for tidal influence on the coastal groundwater system, in which two main processes act simultaneously. First, sea tide causes a pressure head wave which propagates into the saturated zone of the aquifer, governed by the diffusivity of the aquifer (Ks/Ss). Second, this pressure head wave is attenuated at the water table due to the unsaturated flow within the capillary fringe which occurs during groundwater level oscillations. Because the tidal forcing acts on the sea-floor boundary and the attenuation of the groundwater level due to capillary effect acts on the groundwater table, two dimensional distributions of time-lag and hydraulic head amplitude are created. The capillary effect in the unsaturated zone plays a key role not only in the water table fluctuations as shown previously, but also on the salinity fluctuations in the fresh-saline water interface. Unsaturated flow dynamics controls the actual movement of the entire fresh water body, which results in simultaneous fluctuations of the groundwater level and the fresh-saline water interface.
In the ongoing flood of studies of memory in its manifold forms and meanings, the no less powerful subject of forgetting tends to be forgotten. We often think of forgetting as a passive process, something that simply “happens” to us and to other living beings; but many of the studies in this inter-disciplinary volume reveal the active and even creative nature of forgetting, its positive features, and its varied roles in a wide series of cultural and intercultural templates. Neuroscientists joined with historians, philologists, a linguist, philosophers, sociologists and anthropologists, an archaeologist and an artist in the two joint workshops that generated this volume, under the auspices of the Zukunftskolleg at the University of Konstanz and the Martin Buber Society of Fellows at the Hebrew University of Jerusalem. The lively exchanges in the workshops are reflected in the comments and discussion that follow many of these experimental, meditative essays.
Crisis inquiries are intended to serve as instruments for restoring legitimacy. This intended goal has led to particular legitimacy-enhancing institutional choices in the design of these ad hoc institutions. This research utilizes a national panel study to test the effect of institutional attributes of a crisis inquiry and the content of its report on its legitimacy, and the effects of the inquiry findings on public opinion regarding the inquired issue. Our results show that only some institutional attributes predicted the legitimacy of the inquiry findings, whereas the content of the report was strongly and consistently associated with report legitimacy.
A major component of solar thermal systems is the solar absorber, which converts light into heat. We report on achieving high absorptance, excellent adhesion, and high thermal stability of carbon nanotube-based black coatings by applying a layer of Boehmite (AlOOH) on top of the carbon nanotube (CNT) film by soln.-processed spray deposition. The CNT layer made-up by spraying, functions as an absorbing layer and the AlOOH serves as an anti-reflecting and protecting film. The anti-reflecting property of AlOOH layer effectively increases the absorptance of CNT coating by decreasing the reflectance. The effect of the thickness of AlOOH layer on the absorptance, adhesion, and thermal stability of the resulting CNT/AlOOH coating was investigated. The CNT/AlOOH coating with optimized thickness of AlOOH layer shows very high absorptance (α) of 0.975. The adhesion of the coating is in the range of 95-100% with significant increase of thermal stability. This new approach is expected to open new possibilities for fabricating low-cost, highly efficient and thermally stable solar-thermal devices which are based on simple coating processes. [on SciFinder(R)]
We study the nonequilibrium dynamics of the linear-to-zigzag structural phase transition exhibited by an ion chain confined in a trap with periodic boundary conditions. The transition is driven by reducing the transverse confinement at a finite quench rate, which can be accurately controlled. This results in the formation of zigzag domains oriented along different transverse planes. The twists between different domains can be stabilized by the topology of the trap, and under laser cooling the system has a chance to relax to a helical chain with nonzero winding number. Molecular dynamics simulations are used to obtain a large sample of possible trajectories for different quench rates. The scaling of the average winding number with different quench rates is compared to the prediction of the Kibble-Zurek theory, and a good quantitative agreement is found.
Water-repellent (hydrophobic) soils do not wet instantaneously, but only after some time (a few seconds to hours) of soil-particle contact with water. Some plant species can render soils hydrophobic but in this respect, olive trees have scarcely been examined. Measurements of water repellency in olive orchards of different ages in different locations in Israel using the water drop penetration time (WDPT) test have shown that soils tend to become hydrophobic, regardless of texture and structure. A comprehensive study was then performed for an irrigated young and mature olive grove and nearby uncultivated bare soil in the southern part of Israel. The study included intensive WDPT measurements, initial (repellency intensity) and rate of decrease (repellency persistence) for sessile drops placed on the soil surface, cumulative infiltration using tension disc infiltrometer, and monitoring flow in a transparent flow chamber packed with soils from the different plots. The soil from the mature olive plot was noticeably more water repellent than the young plot's soil, and both differed from the uncultivated soil that was fully wettable. The contact angle of a drop placed on the surface of a single layer of soil particles decreased exponentially with time, with a lower decay rate for the mature orchard soil. Cumulative infiltration had a convex pattern for wettable soils and a concave pattern for water-repellent ones. The difference in infiltration pattern was attributed to water/pressure buildup behind the wetting front as a result of the dynamic contact-angle-induced pore resistivity to wetting. The supplemental pressure, also known as dynamic water-entry pressure, increases the infiltration rate beyond that obtained by the capillary pressure per se. The significant correlation between soil sorptivity and the asymptotic infiltration rate, both calculated from the cumulative infiltration curves, and the WDPT substantiates the dependence of pressure overshoot and the rate at which the contact angle decreases prior to pore wetting. The considerable differences in plume shape, size, and internal saturation distribution between the wettable and water-repellent soils, indicating unstable flow in the latter, were also explained by the wettability-dependent water-entry pressure. The outcome of this study indirectly supports the findings that higher surface runoff and erosion are associated with no-till farming in olive orchards, due to the combination of no-till cropping and the near-surface accumulation of hydrophobic organic carbon compounds.
Advanced microscopy methods allow obtaining information on (dynamic) conformational changes in biomolecules via measuring a single molecular distance in the structure. It is, however, extremely challenging to capture the full depth of a three-dimensional biochemical state, binding-related structural changes or conformational cross-talk in multi-protein complexes using one-dimensional assays. In this paper we address this fundamental problem by extending the standard molecular ruler based on Förster resonance energy transfer (FRET) into a two-dimensional assay via its combination with protein-induced fluorescence enhancement (PIFE). We show that donor brightness (via PIFE) and energy transfer efficiency (via FRET) can simultaneously report on e.g., the conformational state of double stranded DNA (dsDNA) following its interaction with unlabelled proteins (BamHI, EcoRV, and T7 DNA polymerase gp5/trx). The PIFE-FRET assay uses established labelling protocols and single molecule fluorescence detection schemes (alternating-laser excitation, ALEX). Besides quantitative studies of PIFE and FRET ruler characteristics, we outline possible applications of ALEX-based PIFE-FRET for single-molecule studies with diffusing and immobilized molecules. Finally, we study transcription initiation and scrunching of E. coli RNA-polymerase with PIFE-FRET and provide direct evidence for the physical presence and vicinity of the polymerase that causes structural changes and scrunching of the transcriptional DNA bubble.
