Vapour-Phase Polymerization of Pyrrole and 3,4-Ethylenedioxythiophene Using Iron(III) 2,4,6-Trimethylbenzenesulfonate

2009 ◽  
Vol 62 (2) ◽  
pp. 133 ◽  
Author(s):  
Priya Subramanian ◽  
Noel Clark ◽  
Bjorn Winther-Jensen ◽  
Douglas MacFarlane ◽  
Leone Spiccia

A new iron(iii) 2,4,6-trimethylbenzenesulfonate (MSA) with composition [Fe(OH2)5(MSA)3] has been prepared from the reaction of Fe(OH)3·xH2O and three molar equivalents of 2,4,6-trimethylbenzenesulfonic acid and used as oxidant in the preparation of highly conducting polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) films for the first time. PPy and PEDOT films grown on non-conducting overhead transparency (polyethylene terephthalate films) using a vapour phase polymerization technique exhibited very high conductivities; 200 ± 20 S cm–1 for PPy and 1000 ± 80 S cm–1 for PEDOT.

2020 ◽  
Vol 501 (1) ◽  
pp. L71-L75
Author(s):  
Cornelius Rampf ◽  
Oliver Hahn

ABSTRACT Perturbation theory is an indispensable tool for studying the cosmic large-scale structure, and establishing its limits is therefore of utmost importance. One crucial limitation of perturbation theory is shell-crossing, which is the instance when cold-dark-matter trajectories intersect for the first time. We investigate Lagrangian perturbation theory (LPT) at very high orders in the vicinity of the first shell-crossing for random initial data in a realistic three-dimensional Universe. For this, we have numerically implemented the all-order recursion relations for the matter trajectories, from which the convergence of the LPT series at shell-crossing is established. Convergence studies performed at large orders reveal the nature of the convergence-limiting singularities. These singularities are not the well-known density singularities at shell-crossing but occur at later times when LPT already ceased to provide physically meaningful results.


1985 ◽  
Vol 5 (9) ◽  
pp. 2272-2278
Author(s):  
R A Akins ◽  
A M Lambowitz

We have developed a sib selection procedure for cloning Neurospora crassa nuclear genes by complementation of mutants. This procedure takes advantage of a modified N. crassa transformation procedure that gives as many as 10,000 to 50,000 stable transformants per microgram of DNA with recombinant plasmids containing the N. crassa qa-2+ gene. Here, we describe the use of the sib selection procedure to clone genes corresponding to auxotrophic mutants, nic-1 and inl. The identities of the putative clones were confirmed by mapping their chromosomal locations in standard genetic crosses and using restriction site polymorphisms as genetic markers. Because we can obtain very high N. crassa transformation frequencies, cloning can be accomplished with as few as five subdivisions of an N. crassa genomic library. The sib selection procedure should, for the first time, permit the cloning of any gene corresponding to an N. crassa mutant for which an appropriate selection can be devised. Analogous procedures may be applicable to other filamentous fungi before the development of operational shuttle vectors.


2013 ◽  
Vol 8 (S299) ◽  
pp. 32-33
Author(s):  
L.M. Close ◽  
K. Follette ◽  
J.R. Males ◽  
K. Morzinski ◽  
T.J. Rodigas ◽  
...  

AbstractWe utilized the new high-order (250-378 mode) Magellan Adaptive Optics system (MagAO) to obtain very high-resolution science in the visible with MagAO's VisAO CCD camera. In the good-median seeing conditions of Magellan (0.5–0.7″) we find MagAO delivers individual short exposure images as good as 19 mas optical resolution. Due to telescope vibrations, long exposure (60s) r' (0.63μm) images are slightly coarser at FWHM = 23-29 mas (Strehl ~ 28%) with bright (R < 9 mag) guide stars. These are the highest resolution filled-aperture images published to date. Images of the young (~ 1 Myr) Orion Trapezium θ1 Ori A, B, and C cluster members were obtained with VisAO. In particular, the 32 mas binary θ1 Ori C1C2 was easily resolved in non-interferometric images for the first time. Relative positions of the bright trapezium binary stars were measured with ~ 0.6–5 mas accuracy. In the second commissioning run we were able to correct 378 modes and achieved good contrasts (Strehl>20% on young transition disks at Hα). We discuss the contrasts achieved at Hα and the possibility of detecting low mass (~ 1–5 Mjup) planets (past 5AU) with our new SAPPHIRES survey with MagAO at Hα.


Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 635
Author(s):  
Liam A. Bullock ◽  
John Parnell ◽  
Joseph G.T. Armstrong ◽  
Magali Perez ◽  
Sam Spinks

Gold grains, up to 40 μm in size and containing variable percentages of admixed platinum, have been identified in coals from the Leinster Coalfield, Castlecomer, SE Ireland, for the first time. Gold mineralisation occurs in sideritic nodules in coals and in association with pyrite and anomalous selenium content. Mineralisation here may have reflected very high heat flow in foreland basins north of the emerging Variscan orogenic front, responsible for gold occurrence in the South Wales Coalfield. At Castlecomer, gold (–platinum) is attributed to precipitation with replacive pyrite and selenium from groundwaters at redox interfaces, such as siderite nodules. Pyrite in the cores of the nodules indicates fluid ingress. The underlying Caledonian basement bedrock is mineralised by gold, and thus likely provided a source for gold. The combination of the gold occurrences in coal in Castlecomer and in South Wales, proximal to the Variscan orogenic front, suggests that these coals along the front could comprise an exploration target for low-temperature concentrations of precious metals.


2021 ◽  
Vol 20 (1) ◽  
pp. 47-62
Author(s):  
Gildas G.B. Todinanahary ◽  
Nomeniarivelo Hasintantely ◽  
Igor Eeckhaut ◽  
Thierry Lavitra

The distribution of larvae and recruitment of scleractinians in the southwest region of Madagascar were evaluated for the first time between October 2013 and September 2014 at 3 sites. The presence of coral larvae (planulae) was monitored through weekly sampling using a plankton net and the recruitment rate evaluated by monthly sampling of the newly settled corals (<1 year stage) on recruitment tiles and by a monitoring of the recruitment of juveniles (1< Juveniles < 2 years) using the quadrat method. Planulae were present in the plankton for 9 months during the survey. The recorded mean annual density of planula varied from 0.43 ± 0.41 larvae m-3 to 3.23 ± 5.72 larvae m-3 depending on site, with a peak in larval density towards the end of November and the beginning of December. The variability in the occurrence of planula is very high and implied that the density observed in the year does not present a significant difference between the sites (pKW=0.33). The average density of total recruits was 620.13 ± 621.30 recruits m-2, 40.28 ± 50.97 recruits m-2 and 36.34 ± 33.82 recruits m-2, respectively at the sites of Nosy Tafara, Grande Vasque and Rose Garden. Seasonal distribution of coral recruitment was different between the sites. The mean annual density of newly settled recruits (< 1 month stage) was significantly higher at Nosy Tafara with 94.91±101.08 recruits m-2 compared to Grande Vasque and Rose Garden with 18.75±34.32 recruits m-2 and 11.57±18.47 recruits m-2 (pKW<0.001), respectively. The highest density of newly settled recruits was observed between October to December. Higher density of recruits was also observed in March at Nosy Tafara and in May at all three sites. Results of juvenile monitoring showed high rates (> 10 juveniles m-2) compared to other regions and the threshold, but it revealed high mortality among recruits. Coral recruitment in the southwest region of Madagascar was found to be high and could result in increased resilience of the coral reef assemblages.


2021 ◽  
Vol 8 (2) ◽  
pp. 01-07
Author(s):  
Brenda Bertado Cortes ◽  
Brian Madariaga Cortes ◽  
Massiel Zenteno Zenteno ◽  
Bayron Alexander Sandoval Bonilla

Chronyc lymphosytic inflammation with pontine perivascular enhacement responsive to steroids (CLIPPERS), described for the first time in 2010 by Pittock and collaborators, is a rare inflammatory disease of the central nervous system (SNC) characterized by the presence of punctuate or curvilinear lesions described like “salt and pepper” appearance on the magnetic resonance imaging (MRI), that enhance with Gadoliniumn administration; this lesions show an exquisite response to corticosteroid therapy. The etiology of this disease remains unknown. However, the existing articles suggest an autoimmune component, which may or may not be related to other autoinmmune, infectious or malignant pathologies. Due to the above, it is generally considered that in order to reach the diagnosis of CLIPPERS, the possibility of other more common or aggressive pathologies must first be ruled out through extensive investigation. However, if the clinical and imaging presentation are typical and there is a very high suspicion of CLIPPERS, early initiation of glucosteroid therapy may be recommended. There is no unanimous therapy plan due to the few cases reported worldwide thus far. In cases of severe relapses or atypical behavior, both clinical and radiological, it is recommended to consider a stereotactic biopsy of the lesion to integrate the definitive diagnosis. Because it is a rare disease, it is relatively unknown to first- contact medical personnel; in our particular case, this leads to referral to the neurosurgery department who, thanks to their experience, have considered a demilinizing disease as a diagnostic possibility and requested an assessment by the neurology department. Here, we report the evolution and management of three diagnosed cases of CLIPPERS at a single Third-level Medical Center in México; based on clinical, radiological and neuropathological findings; as well as highlighting the importance of lesion biopsy in selected cases.


Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3260 ◽  
Author(s):  
Carlin ◽  
Masuero ◽  
Guella ◽  
Vrhovsek ◽  
Mattivi

Glycosides are ubiquitous plant secondary metabolites consisting of a non-sugar component called an aglycone, attached to one or more sugars. One of the most interesting aglycones in grapes and wine is methyl salicylate (MeSA), an organic ester naturally produced by many plants, particularly wintergreens. To date, nine different MeSA glycosides from plants have been reported, mainly spread over the genera Gaultheria, Camellia, Polygala, Filipendula, and Passiflora. From a sensorial point of view, MeSA has a balsamic-sweet odor, known as Wintergreen. MeSA was found in Vitis riparia grapes, in Vitis vinifera sp. and in the Frontenac interspecific hybrid. We found that the MeSA glycosides content in Verdicchio wines and in some genetically related varieties (Trebbiano di Soave and Trebbiano di Lugana) was very high. In order to understand which glycosides were present in wine, the methanolic extract of Verdicchio wine was injected into a UPLC-Q-TOF-HDMS and compared to the extracts of different plants rich in such glycosides. Using pure standards, we confirmed the existence of two glycosides in wine: MeSA 2-O--d-glucoside and MeSA 2-O--d-xylopyranosyl (1-6) -d-glucopyranoside (gaultherin). For the first time, we also tentatively identified other diglycosides in wine: MeSA 2-O--l-arabinopyranosyl (1-6)--d-glucopyranoside (violutoside) and MeSA 2-O--d-apiofuranosyl (1-6)--d-glucopyranoside (canthoside A), MeSA 2-O--d-glucopyranosyl (1-6)-O--d-glucopyranoside (gentiobioside) and MeSA 2-O--l-rhamnopyranosyl (1-6)--d-glucopyranoside (rutinoside). Some of these glycosides have been isolated from Gaultheria procumbens leaves by preparative liquid chromatography and structurally annotated by 1H- and 13C-NMR analysis. Two of the peaks isolated from Gaultheria procumbens leaves, namely MeSA sambubioside and MeSA sophoroside, were herein observed for the first time. Six MeSA glycosides were quantified in 64 Italian white wines, highlighting the peculiar content and pattern in Verdicchio wines and related cultivars. The total concentration in bound and free MeSA in Verdicchio wines varied in the range of 456–9796 g/L and 5.5–143 g/L, respectively, while in the other wines the bound and free MeSA was below 363 g/L and 12 g/L, respectively. As this compound’s olfactory threshold is between 50 and 100 g/L, our data support the hypothesis that methyl salicylate can contribute to the balsamic scent, especially in old Verdicchio wines.


2018 ◽  
Vol 9 (2) ◽  
Author(s):  
Gian Paolo Barbetta ◽  
Paolo Canino ◽  
Stefano Cima ◽  
Flavio Verrecchia

AbstractThe latest census of Italian nonprofit organizations – compared with the previous one – showed a significant development of the nonprofit sector between 2001 and 2011. The number of organizations increased more than 28 % while the growth of employees (about 61 %) was even more impressive.These results notwithstanding, the mere comparison of aggregate census data does not give a true understanding of the dynamic of the sector. The entry and exit of organizations, as well as their migration between different sectors of activity, or geographical areas, can be analyzed properly only using firm-level panel data, but these data are rarely available so that only a few authors had a chance to use them. In this paper, we try to fill this gap using firm-level panel data for the first time in Italy. Our analysis tempers the optimism arising from aggregate data. We show that: a) part of the growth is determined by the emergence of already active organizations that were not detected a decade ago; b) because of low barriers, the entry of new nonprofit organizations is very relevant, but their net contribution to the growth of employment is quite small; c) opposite to what happened in other countries, the exit of nonprofit organizations is very significant, and d) organizations that were already active a decade ago gave the most important contribution to the growth of employment. We also investigate geographical trends, showing that the slower growth of the nonprofit sector in Southern Italy depends on the very high exit rate of the area, while the entry rate is more or less in line with the rest of the country.


Proceedings ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 9
Author(s):  
Ka-Wah Wong ◽  
Rodrigo S. Nemmen ◽  
Jimmy A. Irwin ◽  
Dacheng Lin

The nearby M87 hosts an exceptional relativistic jet. It has been regularly monitored in radio to TeV bands, but little has been done in hard X-rays ≳10 keV. For the first time, we have successfully detected hard X-rays up to 40 keV from its X-ray core with joint Chandra and NuSTAR observations, providing important insights to the X-ray origins: from the unresolved jet or the accretion flow. We found that the hard X-ray emission is significantly lower than that predicted by synchrotron self-Compton models introduced to explain very-high-energy γ -ray emission above a GeV. We discuss recent models to understand these high energy emission processes.


Author(s):  
I. Chasiotis ◽  
S. W. Cho ◽  
T. A. Friedmann ◽  
J. P. Sullivan

The mechanics of hydrogen-free tetrahedral amorphous diamond-like carbon (ta-C) MEMS structures have been investigated in connection with their elastic and failure properties. For this purpose, micro-tension specimens of thicknesses between 1.2 μm and 1.8 μm and gage widths of 10 μm or 50 μm have been fabricated by the Sandia National Laboratories (SNL). The mechanical characterization has been conducted via in situ AFM measurements and Digital Image Correlation (DIC) data strain analysis and the deformation fields of uniform tension specimens and internally notched specimens with acute notches (K=27) have been experimentally obtained. The elastic modulus and Poisson’s ratio were measured for the first time directly from the specimens averaging 750 GPa and ν=0.16 respectively, while the tensile strength was found to be very consistent averaging 7.0 GPa. Stressed material domains with smaller dimensions in the vicinity of micronotches exhibited even higher failure strength reaching an average of 11.5 GPa with about 10% scatter. AFM images of specimens under high tensile stresses have also indicated the possibility of an sp3 to sp2 phase transformation on the film surface at very high tensile stresses (&gt;6 GPa).


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