Continuous monitoring can improve indistinguishability of a single-photon source

A new engineering technique using continuous quantum measurement in conjunction with feed-forward is proposed to improve indistinguishability of a single-photon source. The technique involves continuous monitoring of the state of the emitter, processing the noisy output signal with a simple linear estimation algorithm, and feed forward to control a variable delay at the output. In the weak coupling regime, the information gained by monitoring the state of the emitter is used to reduce the time uncertainty inherent in photon emission from the source, which improves the indistinguishability of the emitted photons.Comment: 4 pages, 4 figure

Self-cleaning properties of TiO2/palygorskite and TiO2/halloysite nanocomposite coatings

Tubular halloysite and microfibrous palygorskite clay mineral combined with nanocrystalline TiO 2 are involved in the preparation of nanocomposite films on glass substrates via sol-gel route at 450°C. The synthesis employing nonionic surfactant molecule as pore directing agent along with the acetic acid-based sol-gel route without addition of water molecules. Drying and thermal treatment of composite films ensure elimination of organic material lead to the formation of TiO 2 nanoparticles homogeneously distributed on the palygorskite and halloysite surfaces. Nanocomposite films without cracks of active anatase crystal phase on palygorskite and halloysite surfaces are characterized by microscopy techniques, UV-Vis spectroscopy, and porosimetry methods in order to examine their structural properties. The composite palygorskite- TiO 2 and halloysite/ TiO 2 films with variable quantities of palygorskite and halloysite were tested as photocatalysts in the photo-oxidation of Basic Blue 41 azo dye in water. These nanocomposite films proved to be most promising photocatalysts and highly effective to dye’s decoloration in spite of small amount of palygorskite/ TiO 2 or halloysite/ TiO 2 catalyst immobilized onto glass substrates

Spirituality and Composition: One Teacher\u27s Thoughts

The author explores her ambivalence about combining her interest in spirituality and her composition teaching

The Pandemic Forces Us Back to Our Roots: Book Reviews Introduction

Book Reviews Introductio

29Si AND 27Al CPMAS NMR QUALITATIVE AND QUANTITATIVE ANALYSIS OF KAOLINITE AND DICKITE IN KOS ISLAND KAOLINS, GREECE

Η μέθοδος του Πυρηνικού Μαγνητικού Συντονισμού (NMR) και οι τεχνικές 7ΑΙ και 9Si CPMAS NMR εφαρμόστηκαν στην έρευνα επιλεγμένων δειγμάτων υδροθερμικά εξαλλοιωμένων ρυολίθων της νήσου Κω. Επιλέχθηκαν δείγματα πλούσια σε καολινίτη και δικίτη που είχαν ήδη αναλυθεί και με τη χρήση της Περιθλασιμετρίας Ακτινών Χ και σημειακών χημικών αναλύσεων (που ελήφθησαν από το HL·κτpovικό Μικροσκόπιο). Ο καολινίτης και ο δικίτης μπορούν να ανιχνευτούν βάση των φασμάτων του τετραεδρικού Πυριτίου και του οκταεδρικού Αργιλίου (με τις τεχνικές 27ΑΙ και 29Si CPMAS NMR). Βρέθηκε ότι η αλληλεπίδραση των ανακλάσεων υποβαθμίζεται και το σχήμα των ανακλάσεων γίνεται οξύληκτο όταν ο χρόνος αποφόρτισης (pulse recycling delay) είναι υψηλός (10 δευτεpόL·πτa). Ο λόγος οκταεδρικό Αργίλιο / τετραεδρικό Πυρίτιο των ορυκτών της ομάδας του καολινίτη όπως μετρήθηκε από τις τεχνικές του Πυρηνικού Μαγνητικού Συντονισμού βρέθηκε παρόμοιος με αυτόν που προέκυψε από τις σημειακές χημικές αναλύσεις. Σε αυτήν την εργασία παρουσιάζεται για πρώτη φορά μια προσέγγιση που κάνει εφικτή τη λήψη οξύληκτων ανακλάσεων Πυρηνικού Μαγνητικού Συντονισμού σε στερεά δείγματα (27Al and 29Si CPMAS NMR). Το οξύληκτο σχήμα των ανακλάσεων μεγιστοποιεί την ακρίβεια των μετρήσεων της θέσεων των ανακλάσεων και του λόγου οκταεδρικό Αργίλιο / τετραεδρικό Πυρίτιο.The application of 27Al and 29Si CPMAS NMR spectroscopy to the investigation of selected /caolinite and dickite bearing samples from hydrothermally altered rhyolites of Kos island is tested using also XRD and analytical SEM-EDS data. Kaolinite and dickite, can be detected by both their tetrahedral Si and octahedral Al CPMAS NMR spectra. It was found that the interference of the peaks become less significant and the shape of the peaL· narrow when the pulse recycling delay is high (up to 10s). The octahedral Al / tetrahedral Si ratios of kaolinite group mineral forms from samples showing various degrees of alteration, calculated from the NMR spectra, were found to be very similar to these derived from the structural formulae of SEM-EDS microanalyses. In this work it is presented for the first time an approach to provide narrow CPMAS NMR peaks. The narrow shape of the peaks provides accurate measurements of the exact position of the peaL· and the octahedral Al / tetrahedral Si ratios

Nanocrystalline TiO2 and halloysite clay mineral composite films prepared by sol-gel method:Synergistic effect and the case of silver modification to the photocatalytic degradation of basic blue- 41 azo dye in water

Tubular halloysite clay mineral and nanocrystalline TiO2 were incorporated in the preparation of nanocomposite films on glass substrates via sol-gel method at 450 °C. The synthesis involves a simple chemical method employing nonionic surfactant molecule as pore directing agent along with the acetic acid-based sol-gel route without addition of water molecules. Drying and thermal treatment of composite films ensure elimination of organic material and lead to the formation of TiO2 nanoparticles homogeneously distributed on the surface of the halloysite. Nanocomposite films without cracks of active anatase crystal phase and small crystallite size on halloysite nanotubes are characterized by microscopy techniques and porosimetry methods in order to examine their structural properties. The composite halloysite-TiO2 films with variable quantities of halloysite were examined as photocatalysts to the discoloration of Basic Blue 41 azo dye in water. These nanocomposite films proved to be very promising photocatalysts and highly effective to dye's discoloration in spite of small amount of halloysite/TiO2 catalyst immobilized onto glass substrates. It also has been shown that the efficiency of the halloysite/TiO2 films could be further improved when silver particles were deposited on their surface after successful adsorption from an aqueous solution of a silver salt and UV reduction of the adsorbed ions

Tharp, Twyla. Keep It Moving: Lessons for the Rest of Your Life. Simon and Schuster, 2019, 190 pages.

Tharp, Twyla. Keep It Moving: Lessons for the Rest of Your Life. Simon and Schuster, 2019, 190 pages

A Reflection on Habitual Belief and Habitual Doubt

Some people are habitual believers while others are habitual doubters. I\u27 m a believer, but doubting others helps me believe myself I explore the idea that examining our individual habitual relationships with believing and doubting helps us think better and relate better to others and to ourselves

The Core, Periphery, and Beyond: Stock Market Comovements among EU and Non-EU Countries

We thank conference participants at the 2016 Financial Management Association and our discussant Fernando Moreira, and two anonymous referees for immensely helpful comments. We also thank Andrew Patton and James P. LeSage for sharing their MATLAB codes for computing quantile dependence. The authors of this paper are responsible for any errors or omissions. The Securities and Exchange Commission, as a matter of policy, disclaims responsibility for any private publication or statement by any of its employees. The views expressed herein are those of the authors and do not necessarily reflect the views of the Commission or the authors\u27 colleagues on the staff of the Commission

From Genes to Ecosystems: Resource Availability and DNA Methylation Drive the Diversity and Abundance of Restriction Modification Systems in Prokaryotes

Together, prokaryotic hosts and their viruses numerically dominate the planet and are engaged in an eternal struggle of hosts evading viral predation and viruses overcoming defensive mechanisms employed by their hosts. Prokaryotic hosts have been found to carry several viral defense systems in recent years with Restriction Modification systems (RMs) were the first discovered in the 1950s. While we have biochemically elucidated many of these systems in the last 70 years, we still struggle to understand what drives their gain and loss in prokaryotic genomes. In this work, we take a computational approach to understand the underlying evolutionary drivers of RMs by assessing ‘big data’ signals of RMs in prokaryotic genomes and incorporating molecular data in trait-based mathematical models. Focusing on the Cyanobacteria, we found a large discrepancy in the frequency of RMs per genome in different environmental contexts, where Cyanobacteria that live in oligotrophic nutrient conditions have few to no RMs and those in nutrient-rich conditions consistently have many RMs. While our models agree with the observation that increased nutrient inputs make the selective pressure of RMs more intense, they were unable to reconcile the high numbers of RMs per genome with their potent defensive properties- a situation of apparent overkill. By incorporating viral methylation, an unavoidable effect of RMs, we were able to explain how organisms could carry over 15 RMs. With this discovery, we then tried and reassess the distribution of methyltransferases, an essential component of RMs that can also have alternate physiological rolls in the cell. We expand on conventional wisdom, that methyltransferases that are widely phylogenetically conserved are associated with global cellular regulation. However, we also find that organisms with high numbers of RMs also have a surprising amount of conservation in the methyltransferases that they carry. This data suggests caution should be used in associating phylogenic signals with functional rolls in methyltransferases as different functional rolls seem to overlap in their phylogenetic signal. Indeed, we suggest trait-based modeling may be the best tool in elucidating why organisms with a high selective pressure to maintain RMs appear to have conserved methyltransferase