bluuebunny/crossref_metadata_2025 huggingface dataset:
Regioselective and enantiospecific synthesis of the HSP co-inducer arimoclomol from chiral glycidyl derivatives
Authors: Atkinson Benjamin N. , Woodward Hannah L. , Sipthorp James , Fish Paul V.
Published: November 2017

A new efficient chiral synthesis of arimoclomol is reported from (R)-(−)-glycidyl nosylate with complete retention of chiral integrity.
A general strategy for the synthesis of indoloquinolizine alkaloids via a cyanide-catalyzed imino-Stetter reaction
Authors: Park Eunjoon , Cheon Cheol-Hong
Published: November 2017

A general synthetic strategy applicable to indoloquinolizine alkaloids has been developed using a cyanide-catalyzed imino-Stetter reaction as a key step.
(+)- and (−)-Ascomlactone A: a pair of novel dimeric polyketides from a mangrove endophytic fungus Ascomycota sp. SK2YWS-L
Authors: Liu Zhaoming , Chen Senhua , Qiu Pei , Tan Chunbing , Long Yuhua , Lu Yongjun , She Zhigang
Published: November 2017

Two novel enantiomeric polyketide dimers were obtained from a mangrove endophytic fungus Ascomycota sp. with potential α-glucosidase inhibitory activities.
Highly functional ellipsoidal block copolymer nanoparticles: a generalized approach to nanostructured chemical ordering in phase separated colloidal particles
Authors: Schmidt B. V. K. J. , Wang C. X. , Kraemer S. , Connal L. A. , Klinger D.
Published: November 2017

Spatially controlled introduction of chemical functionalities into ellipsoidal block copolymer nanoparticles is achieved through pre- and post-assembly strategies.
HPLC/PDA/ESI-MS/MS analysis of chamomile decoction and mechanism of its protective effects on aspirin-induced small bowel injuries
Authors: Jabri Mohamed-Amine , Hajji Najla , Wannes Dalanda , Tounsi Haifa , Jridi Mourad , Abdellaoui Afifa , Nasri Moncef , Marzouki Lamjed , Sebai Hichem
Published: November 2017

The aim of the present study is to evaluate the effect of chamomile (Matricaria recutitaL.) decoction extract (CDE) on aspirin-induced small bowel injuries.
A novel self-assembled supramolecular sensor based on thiophene-functionalized imidazophenazine for dual-channel detection of Ag+ in an aqueous solution
Authors: Shi Hai-Xiong , Li Wen-Ting , Li Qiao , Zhang Hai-Li , Zhang You-Ming , Wei Tai-Bao , Lin Qi , Yao Hong
Published: November 2017

A novel dual-channel chemosensor S1 is designed and synthesized, which recognizes Ag+ over other metal ions with high selectivity and sensitivity.
Visualization of filler network in silicone rubber with confocal laser-scanning microscopy
Authors: Liu Min , Kang Ming , Mou Yongren , Chen Kexu , Sun Rong
Published: November 2017

Most of the present studies of filler network structure basically stay in some phenomenological descriptions and classical electron microscopes are restricted by conventional 2-D imaging.
Solar light assisted green synthesis of photoreduced graphene oxide for the high-efficiency adsorption of anionic dyes
Authors: Gong Yani , Qin Chengbing , He Wenjun , Qiao Zhixing , Zhang Guofeng , Chen Ruiyun , Gao Yan , Xiao Liantuan , Jia Suotang
Published: November 2017

Graphene oxide (GO) with unique physical and chemical properties, such as high specific surface area, chemical stability and environmental friendliness, has been considered as an excellent adsorbent to remove organic dyes from polluted water.
Sensitive profiling of trace neurotoxin domoic acid by pressurized capillary electrochromatography with laser-induced fluorescence detection
Authors: Chen Qingai , Deng Lijun , Chi Jinxin , Liu Min , Lin Xucong , Xie Zenghong
Published: November 2017

A stable, sensitive and low-reagent consumption method for the quantification of trace neurotoxin domoic acid (DA) was presented by pressurized capillary electrochromatography (pCEC) with laser-induced fluorescence (LIF) detection.
Improved shellac mediated nanoscale application drug release effect in a gastric-site drug delivery system
Authors: Ma Ke , Qiu Yiping , Fu Yaqin , Ni Qing-Qing
Published: November 2017

Six kinds of nanoscale application are designed in this study. A significant increase of drug release rate can be observed at the gastric site.
Unexpected cleavage of thiacalix[4]arene sulfoxides
Authors: Mikšátko J. , Eigner V. , Lhoták P.
Published: November 2017

Thiacalix[4]arene monosulfoxides possess an unprecedented reactivity towards n-BuLi to form unusual linear structures.
Pattern formation and self-assembly driven by competing interactions
Authors: Pini Davide , Parola Alberto
Published: November 2017

Colloidal fluids interacting via effective potentials which are attractive at the short range and repulsive at the long range have long been raising considerable attention because such an instance provides a simple mechanism leading to pattern formation even for isotropic interactions.
Functional electrospun fibrous scaffolds with dextran-g-poly(l-lysine)-VAPG/microRNA-145 to specially modulate vascular SMCs
Authors: Zhou Peiqiong , Zhou Fang , Liu Bo , Zhao Yunhui , Yuan Xiaoyan
Published: November 2017

Functional electrospun membranes loaded with Dex-g-PLL-VAPG/miR-145 complexes exhibit the excellent ability to modulate SMC phenotype and proliferation locally.
Tailoring of size, emission and surface chemistry of germanium nanoparticles via liquid-phase picosecond laser ablation
Authors: Rodio Marina , Scarpellini Alice , Diaspro Alberto , Intartaglia Romuald
Published: November 2017

We report on the tailoring of the size and emission of germanium nanoparticles via liquid-phase picosecond laser ablation.
Construction of a tetraphenylethene derivative exhibiting high contrast and multicolored emission switching
Authors: Tian Haiyan , Wang Pengpeng , Liu Jing , Duan Yuxin , Dong Yong Qiang
Published: November 2017

Emission of a tetraphenylethene derivative with low symmetry can be switched among three different states with high contrast by external stimuli.
White light emission from gold nanoclusters embedded bacteria
Authors: Goswami Upashi , Basu Srestha , Paul Anumita , Ghosh Siddhartha Sankar , Chattopadhyay Arun
Published: November 2017

Decorating bacterial surface with gold nanoclusters for white light emission.
Purely organic materials for extremely simple all-TADF white OLEDs: a new carbazole/oxadiazole hybrid material as a dual-role non-doped light blue emitter and highly efficient orange host
Authors: Zhang Di , Cao Xudong , Wu Qingjing , Zhang Mucan , Sun Ning , Zhang Xianping , Tao Youtian
Published: November 2017

Extremely simple two-color all-TADF WOLEDs with a single-emissive-layer singe-host/dopant system provide a bright future for high-efficiency low-cost vacuum-deposited WOLEDs.
Comparison of methods for modelling coronal magnetic fields
Authors: Goldstraw E. E. , Hood A. W. , Browning P. K. , Cargill P. J.
Published: November 2017

Aims. Four different approximate approaches used to model the stressing of coronal magnetic fields due to an imposed photospheric motion are compared with each other and the results from a full time-dependent magnetohydrodynamic (MHD) code. The assumptions used for each of the approximate methods are tested by considering large photospheric footpoint displacements.

Methods. We consider a simple model problem, comparing the full non-linear MHD, determined with the Lare2D numerical code, with four approximate approaches. Two of these, magneto-frictional relaxation and a quasi-1D Grad-Shafranov approach, assume sequences of equilibria, whilst the other two methods, a second-order linearisation of the MHD equations and Reduced MHD, are time dependent.

Results. The relaxation method is very accurate compared to full MHD for force-free equilibria for all footpoint displacements, but has significant errors when the plasma β0 is of order unity. The 1D approach gives an extremely accurate description of the equilibria away from the photospheric boundary layers, and agrees well with Lare2D for all parameter values tested. The linearised MHD equations correctly predict the existence of photospheric boundary layers that are present in the full MHD results. As soon as the footpoint displacement becomes a significant fraction of the loop length, the RMHD method fails to model the sequences of equilibria correctly. The full numerical solution is interesting in its own right, and care must be taken for low β0 plasmas if the viscosity is too high.
Deep convolutional neural networks as strong gravitational lens detectors
Authors: Schaefer C. , Geiger M. , Kuntzer T. , Kneib J.-P.
Published: November 2017

Context. Future large-scale surveys with high-resolution imaging will provide us with approximately 105 new strong galaxy-scale lenses. These strong-lensing systems will be contained in large data amounts, however, which are beyond the capacity of human experts to visually classify in an unbiased way. Aims. We present a new strong gravitational lens finder based on convolutional neural networks (CNNs). The method was applied to the strong-lensing challenge organized by the Bologna Lens Factory. It achieved first and third place, respectively, on the space-based data set and the ground-based data set. The goal was to find a fully automated lens finder for ground-based and space-based surveys that minimizes human inspection.

Methods. We compared the results of our CNN architecture and three new variations (“invariant” “views” and “residual”) on the simulated data of the challenge. Each method was trained separately five times on 17 000 simulated images, cross-validated using 3000 images, and then applied to a test set with 100 000 images. We used two different metrics for evaluation, the area under the receiver operating characteristic curve (AUC) score, and the recall with no false positive (Recall0FP).

Results. For ground-based data, our best method achieved an AUC score of 0.977 and a Recall0FP of 0.50. For space-based data, our best method achieved an AUC score of 0.940 and a Recall0FP of 0.32. Adding dihedral invariance to the CNN architecture diminished the overall score on space-based data, but achieved a higher no-contamination recall. We found that using committees of five CNNs produced the best recall at zero contamination and consistently scored better AUC than a single CNN.

Conclusions. We found that for every variation of our CNN lensfinder, we achieved AUC scores close to 1 within 6%. A deeper network did not outperform simpler CNN models either. This indicates that more complex networks are not needed to model the simulated lenses. To verify this, more realistic lens simulations with more lens-like structures (spiral galaxies or ring galaxies) are needed to compare the performance of deeper and shallower networks.
TheGaia-ESO Survey: open clusters inGaia-DR1
Authors: Randich S. , Tognelli E. , Jackson R. , Jeffries R. D. , Degl’Innocenti S. , Pancino E. , Fiorentin P. Re , Spagna A. , Sacco G. , Bragaglia A. , Magrini L. , Prada Moroni P. G. , Alfaro E. , Franciosini E. , Morbidelli L. , Roccatagliata V. , Bouy H. , Bravi L. , Jiménez-Esteban F. M. , Jordi C. , Zari E. , Tautvaišiene G. , Drazdauskas A. , Mikolaitis S. , Gilmore G. , Feltzing S. , Vallenari A. , Bensby T. , Koposov S. , Korn A. , Lanzafame A. , Smiljanic R. , Bayo A. , Carraro G. , Costado M. T. , Heiter U. , Hourihane A. , Jofré P. , Lewis J. , Monaco L. , Prisinzano L. , Sbordone L. , Sousa S. G. , Worley C. C. , Zaggia S.
Published: November 2017

Context.Determination and calibration of the ages of stars, which heavily rely on stellar evolutionary models, are very challenging, while representing a crucial aspect in many astrophysical areas.

Aims.We describe the methodologies that, taking advantage ofGaia-DR1 and theGaia-ESO Survey data, enable the comparison of observed open star cluster sequences with stellar evolutionary models. The final, long-term goal is the exploitation of open clusters as age calibrators.

Methods.We perform a homogeneous analysis of eight open clusters using theGaia-DR1 TGAS catalogue for bright members and information from theGaia-ESO Survey for fainter stars. Cluster membership probabilities for theGaia-ESO Survey targets are derived based on several spectroscopic tracers. TheGaia-ESO Survey also provides the cluster chemical composition. We obtain cluster parallaxes using two methods. The first one relies on the astrometric selection of a sample of bona fide members, while the other one fits the parallax distribution of a larger sample of TGAS sources. Ages and reddening values are recovered through a Bayesian analysis using the 2MASS magnitudes and three sets of standard models. Lithium depletion boundary (LDB) ages are also determined using literature observations and the same models employed for the Bayesian analysis.

Results.For all but one cluster, parallaxes derived by us agree with those presented in Gaia Collaboration (2017, A&A, 601, A19), while a discrepancy is found for NGC 2516; we provide evidence supporting our own determination. Inferred cluster ages are robust against models and are generally consistent with literature values.

Conclusions.The systematic parallax errors inherent in theGaiaDR1 data presently limit the precision of our results. Nevertheless, we have been able to place these eight clusters onto the same age scale for the first time, with good agreement between isochronal and LDB ages where there is overlap. Our approach appears promising and demonstrates the potential of combiningGaiaand ground-based spectroscopic datasets.
The intrinsic shape of bulges in the CALIFA survey
Authors: Costantin L. , Méndez-Abreu J. , Corsini E. M. , Eliche-Moral M. C. , Tapia T. , Morelli L. , Dalla Bontà E. , Pizzella A.
Published: November 2017

Context.The intrinsic shape of galactic bulges in nearby galaxies provides crucial information to separate bulge types.

Aims.We aim to derive accurate constraints to the intrinsic shape of bulges to provide new clues on their formation mechanisms and set new limitations for future simulations.

Methods.We retrieved the intrinsic shape of a sample of CALIFA bulges using a statistical approach. Taking advantage of GalMer numerical simulations of binary mergers we estimated the reliability of the procedure. Analyzing thei-band mock images of resulting lenticular remnants, we studied the intrinsic shape of their bulges at different galaxy inclinations. Finally, we introduced a new (B/A,C/A) diagram to analyze possible correlations between the intrinsic shape and the properties of bulges.

Results.We tested the method on simulated lenticular remnants, finding that for galaxies with inclinations of 25° ≤θ≤ 65° we can safely derive the intrinsic shape of their bulges. We found that our CALIFA bulges tend to be nearly oblate systems (66%), with a smaller fraction of prolate spheroids (19%), and triaxial ellipsoids (15%). The majority of triaxial bulges are in barred galaxies (75%). Moreover, we found that bulges with low Sérsic indices or in galaxies with low bulge-to-total luminosity ratios form a heterogeneous class of objects; additionally, bulges in late-type galaxies or in less massive galaxies have no preference for being oblate, prolate, or triaxial. On the contrary, bulges with high Sérsic index, in early-type galaxies, or in more massive galaxies are mostly oblate systems.

Conclusions.We concluded that various evolutionary pathways may coexist in galaxies, with merging events and dissipative collapse being the main mechanisms driving the formation of the most massive oblate bulges and bar evolution reshaping the less massive triaxial bulges.
Possible systematics in the VLBI catalogs as seen from Gaia
Authors: Liu N. , Zhu Z. , Liu J.-C.
Published: November 2017

Aims. In order to investigate the systematic errors in the very long baseline interferometry (VLBI) positions of extragalactic sources (quasars) and the global differences between Gaia and VLBI catalogs, we use the first data release of Gaia (Gaia DR1) quasar positions as the reference and study the positional offsets of the second realization of the International Celestial Reference Frame (ICRF2) and the Goddard VLBI solution 2016a (gsf2016a) catalogs.

Methods. We select a sample of 1032 common sources among three catalogs and adopt two methods to represent the systematics: considering the differential orientation (offset) and declination bias; analyzing with the vector spherical harmonics (VSH) functions.

Results. Between two VLBI catalogs and Gaia DR1, we find that: i) the estimated orientation is consistent with the alignment accuracy of Gaia DR1 to ICRF, of ~0.1 mas, but the southern and northern hemispheres show opposite orientations; ii) the declination bias in the southern hemisphere between Gaia DR1 and ICRF2 is estimated to be +152 μas, much larger than that between Gaia DR1 and gsf2016a which is +34 μas. Between two VLBI catalogs, we find that: i) the rotation component shows that ICRF2 and gsf2016a are generally consistent within 30 μas; ii) the glide component and quadrupole component report two declination-dependent offsets: dipolar deformation of ~+50 μas along the Z-axis, and quadrupolar deformation of ~−50 μas that would induce a pattern of sin2δ.

Conclusions. The significant declination bias between Gaia DR1 and ICRF2 catalogs reported in previous studies is possibly attributed to the systematic errors of ICRF2 in the southern hemisphere. The global differences between ICRF2 and gsf2016a catalogs imply that possible, mainly declination-dependent systematics exit in the VLBI positions and need further investigations in the future Gaia data release and the next generation of ICRF.
Significantly high polarization degree of the very low-albedo asteroid (152679) 1998 KU2
Authors: Kuroda Daisuke , Ishiguro Masateru , Watanabe Makoto , Hasegawa Sunao , Sekiguchi Tomohiko , Naito Hiroyuki , Usui Fumihiko , Imai Masataka , Sato Mitsuteru , Kuramoto Kiyoshi
Published: November 2017

We present a unique and significant polarimetric result regarding the near-Earth asteroid (152679) 1998 KU2, which has a very low geometric albedo. From our observations, we find that the linear polarization degrees of 1998 KU2are 44.6 ± 0.5% in theRCband and 44.0 ± 0.6% in theVband at a solar phase angle of 81.0°. These values are the highest of any known airless body in the solar system (i.e., high-polarization comets, asteroids, and planetary satellites) at similar phase angles. This polarimetric observation is not only the first for primitive asteroids at large phase angles, but also for low-albedo (<0.1) airless bodies. Based on spectroscopic similarities and polarimetric measurements of materials that have been sorted by size in previous studies, we conjecture that 1998 KU2has a highly microporous regolith structure comprising nano-sized carbon grains on the surface.
Whole-body Cryotherapy as a Recovery Technique after Exercise: A Review of the Literature
Authors: Rose Catriona , Edwards Kate , Siegler Jason , Graham Kenneth , Caillaud Corinne
Published: November 2017

This review aims to evaluate the current body of literature investigating the effect of whole body cryotherapy on recovery after exercise. A systematic search was conducted to investigate the effect of whole body cryotherapy (WBC, exposure to temperatures between −110 to −190°C) on markers of recovery after damaging exercise in healthy, physically active subjects. Of the 16 eligible articles extracted, ten induced muscle damage using controlled exercise in a laboratory setting, while six induced damage during sport-specific training. Results indicated that muscle pain was reduced in 80% of studies following WBC. Two applied studies found recovery of athletic capacity and performance with WBC improved, variables of this nature were also improved in 71% of studies using controlled exercise. Further benefits of WBC treatment included reduction of systemic inflammation and lower concentrations of markers for muscle cell damage. These results suggest that WBC may improve recovery from muscle damage, with multiple exposures more consistently exhibiting improvements in recovery from pain, loss of muscle function, and markers of inflammation and damage. The diversity in muscle damage protocols, exposure timing with regards to exercise, as well as temperatures, duration and frequencies of exposure, make specific recommendations preliminary at present.
Resting Autonomic Function in Active and Insufficiently Active People Living with HIV
Authors: Quiles Norberto , Garber Carol , Ciccolo Joseph
Published: November 2017

Autonomic dysfunction appears to be prevalent in people living with HIV/AIDS (PLWHA). However, there are limited data on the resting autonomic responses to exercise in active and insufficiently active PLWHA. We aimed to determine whether active PLWHA have better autonomic responses compared with insufficiently active PLWHA. Active PLWHA receiving anti-retroviral therapy (n=13) and insufficiently active PLWHA (n=10) were recruited. A 10-min recording of the supine electrocardiogram was taken. Resting heart rate variability was analyzed from this electrocardiogram. Parasympathetic modulation, as measured by high frequency power in normalized units, was greater in active PLWHA when compared to insufficiently active PLWHA (41.0±15.6 vs. 25.2±9.7; p<0.05). Sympathetic modulation as measured by low frequency power in normalized units was greater in insufficiently active PLWHA when compared to active PLWHA (55.6±15.8 vs 79.3±17.5; p<0.05). Sympathovagal balance as measured by low frequency/high frequency ratio was greater in insufficiently active PLWHA when compared to active PLWHA (3.4±1.8 vs 1.6±0.9; p<0.05), indicating greater parasympathetic dominance in the active group. In conclusion, PLWHA who regularly exercised demonstrated enhanced autonomic function compared with insufficiently active PLWHA. These results suggest that exercise is associated with enhanced autonomic function, and may improve cardiovascular risk.
Alles kann, nichts muss
Authors: Dißmann Steffen
Published: November 2017

Autismus Wenn Kinder autistische Symptome zeigen, empfiehlt es sich, so offen und unvoreingenommen wie möglich hinzuschauen. Denn
generell gilt: Alles kann und nichts muss. Nicht jeder Verdacht muss in einer Diagnose münden und nicht jede Diagnose ist leicht zu
erkennen. Allerdings gibt es Beobachtungskriterien, die der Diagnosefindung zweckdienlich sein können – wir stellen sie Ihnen vor.
Discovery of Novel Thiazol-2-Amines and Their Analogues as Bioactive Molecules: Design, Synthesis, Docking and Biological Evaluation
Authors: Verma Anil , Bishnoi Abha , Fatma Shaheen , Parveen Huda , Singh Vineeta
Published: November 2017

A simple and highly efficient procedure for the synthesis of novel thiazol-2-amines, via Mannich reaction with secondary amines, is described. The newly synthesized derivatives 8(a-e) and 9(a-e) were characterized by 1H NMR, 13C NMR, IR, Mass spectroscopy and elemental analysis. All the derivatives were evaluated for their in-vitro anti-microbial activity against a panel of pathogenic strains of bacteria and fungi. The SAR showed that the secondary amines had a significant impact on the in-vitro antimicrobial activity of this class of agents. The most potent analogue N-((1H-benzo[d]imidazol-1-yl)methyl)-N-(2(trifluoromethyl)phenyl)-4,5-dihydrothiazol-2-amine (8c) showed excellent inhibition with MIC (zoi) 6.25 (22.5), 25 (21.5) and 25 (18) µg/mL against E. coli, S. typhi and P. aeruginosa respectively as compared to the standard drug. Molecular docking results suggest that compound exhibited inhibitory activity by binding of the title compound within the active sites of the inhibiting Enoyl ACP reductase, Lipid A, Pyridoxal kinase and type I DHQase enzymes. The compound exhibited promising anti-microbial activity which can be further explored as potential lead for the development of cheaper, safe, effective and potent drugs against resistant microbial parasites.
CT and MRI Findings in Cerebral Aspergilloma
Authors: Gärtner Friederike , Forstenpointner Julia , Ertl-Wagner Birgit , Hooshmand Babak , Riedel Christian , Jansen Olav
Published: November 2017

Purpose Invasive aspergillosis usually affects immunocompromised patients. It carries a high risk of morbidity and mortality and usually has a nonspecific clinical presentation. Early diagnosis is essential in order to start effective treatment and improve clinical outcome.

Materials and Methods In a retrospective search of the PACS databases from two medical centers, we identified 9 patients with histologically proven cerebral aspergilloma. We systematically analyzed CT and MRI imaging findings to identify typical imaging appearances of cerebral aspergilloma.

Results CT did not show a typical appearance of the aspergillomas. In 100 % (9/9) there was a rim-attenuated diffusion restriction on MRI imaging. Multiple hypointense layers in the aspergillus wall, especially on the internal side, were detected in 100 % on T2-weighted imaging (9/9). Aspergillomas were T1-hypointense in 66 % of cases (6/9) and partly T1-hyperintense in 33 % (3/9). In 78 % (7/9) of cases, a rim-attenuated diffusion restriction was detected after contrast agent application.

Conclusion Nine cases were identified. Whereas CT features were less typical, we observed the following imaging features on MRI: A strong, rim-attenuated diffusion restriction (9/9); onion layer-like hypointense zones, in particular in the innermost part of the abscess wall on T2-weighted images (9/9). Enhancement of the lesion border was present in the majority of the cases (7/9).

Key points 

Citation Format
CO2-Angiografie
Authors: Mensel Birger
Published: November 2017

Diagnostische und interventionelle Prozeduren mit jodhaltigen Kontrastmitteln werden deutschlandweit mit unterschiedlichsten Indikationen
flächendeckend eingesetzt. Auch aufgrund der demografischen Entwicklung nimmt die Zahl der Patienten mit Kontraindikationen, genannt sei
hier die große Gruppe der Patienten mit einer chronischen Niereninsuffizienz, für eine intravasale Gabe von jodhaltigen Kontrastmitteln zu.
Eine weit verbreitete Alternative stellen CO2-geführte Eingriffe dar. CO2 ist nicht nephrotoxisch, nicht allergen und
zeigt keine Wechselwirkungen im Schilddrüsenstoffwechsel. Bis auf die Anwendung am zerebralen und kardialen Gefäßsystem kann CO2
die jodhaltigen Kontrastmittel fast komplett ersetzen. Vorsicht ist bei Patienten mit einer respiratorischen Insuffizienz geboten. Die
Nebenwirkungsrate ist gering. Die Bildqualität CO2-geführter Angiografien ist mit der jodhaltiger Kontrastmittel vergleichbar. Da
die Handhabung für den Anwender aber etwas komplexer und zeitaufwendiger ist, sollte es nur bei indizierten Fällen zum Einsatz kommen.
Gerade Patienten mit nephrologischen Erkrankungen und der häufigen Mitbeteiligung des kardiovaskulären Systems profitieren von der
Möglichkeit CO2-geführter Angiografien.
Impact of Truncated Area on Point Estimate and Intra-Subject Variability in Bioequivalence of Dutasteride with Long Half-Life
Authors: Prasaja Budi , Harahap Yahdiana , Lusthom Windy , Yumi Lia , Sofiana Anna , Sandra Monica , Safira Falah , Chilmi Uci
Published: November 2017

Purpose To investigate the effect of using truncated area under the curve (AUC0-72) on bioequivalence of dutasteride with long half-life in point estimate and intra-subject variability.

Methods Fifteen subjects were enrolled in this single-dose, open-label, randomized two-way crossover design following an overnight fasting with five-week washout period. Plasma samples were collected to 72 h and 144 h following drug administration and dutasteride were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. The pharmacokinetic parameters for bioequivalence assessment were AUC0-72 and AUC0-144.

Results The estimated point and the 90% confidence intervals were 91.07% (84.54–98.11%) for AUC0-72 and 91.43% (84.65–98.75%) for AUC0-144, that is, within the ranges for acceptance of bioequivalence. The intra-subject variability’s were 11.45% for AUC0-72 and 11.87% for AUC0-144.

Conclusions There was no statistically significant difference in point estimated and intra-subject variability between truncated AUC at 72 h and 144=h and the truncated AUC (AUC0-72) approach could be considered for bioequivalence assessment for dutasteride.
Synthesis and characterization of novel polypyrrole hybrid nanotubules incorporated with polyaniline spots
Authors: Kang Kyung Seok , Jee Chan Hyuk , Bae Ji-Hong , Jung Hyo Jin , Huh PilHo
Published: November 2017

Novel hybrid nanostructures composed of the polypyrrole (PPy) as the void nanotubules and the polyaniline (PANi) as the spots were fabricated using a successive synthetic process. Unique phase-separated morphological properties of PPy-PANi hybrid nano-tubules might be caused by the PANi spots distributed randomly in the PPy matrix.
Spectroscopy of Na I and K I atoms embedded in weakly coupled plasma environment
Authors: Das Madhulita , Pradhan Ananta C.
Published: November 2017

The effect of the plasma environment on the structure and properties of Na I and K I atoms is studied using the Fock-space multireference coupled-cluster theory in the relativistic framework. The Debye-Hückle model is used to account the effect of the plasma environment on the atoms. A significant change in the ionization energies, transition energies, transition probabilities, and oscillator strengths of Na I and K I atoms is seen when they are immersed in plasma. The number of bound states and the binding energies of plasma embedded Na I and K I reduce notably in comparison to the isolated plasma free atoms, and these changes tend the system towards gradual instability. The transition spectra of Na I and K I show red shifts in the presence of plasma screening, whereas the oscillator strengths show the red and blue shifts for the same and different principal quantum number transitions, respectively. Furthermore, the presence of plasma screening causes the suppression of spontaneous transition probabilities of plasma embedded Na I and K I atoms. These results are useful to interpret the spectral lines of astrophysical plasma and to get insights into the physical processes that are operative in the celestial objects.
Mechanical response of transient telechelic networks with many-part stickers
Authors: Sing Michelle K. , Ramírez Jorge , Olsen Bradley D.
Published: November 2017

A central question in soft matter is understanding how several individual, weak bonds act together to produce collective interactions. Here, gel-forming telechelic polymers with multiple stickers at each chain end are studied through Brownian dynamics simulations to understand how collective interaction of the bonds affects mechanical response of the gels. These polymers are modeled as finitely extensible dumbbells using an explicit tau-leap algorithm and the binding energy of these associations was kept constant regardless of the number of stickers. The addition of multiple bonds to the associating ends of telechelic polymers increases or decreases the network relaxation time depending on the relative kinetics of association but increases both shear stress and extensional viscosity. The relationship between the rate of association and the Rouse time of dangling chains results in two different regimes for the equilibrium stress relaxation of associating physical networks. In case I, a dissociated dangling chain is able to fully relax before re-associating to the network, resulting in two characteristic relaxation times and a non-monotonic terminal relaxation time with increasing number of bonds per polymer endgroup. In case II, the dissociated dangling chain is only able to relax a fraction of the way before it re-attaches to the network, and increasing the number of bonds per endgroup monotonically increases the terminal relaxation time. In flow, increasing the number of stickers increases the steady-state shear and extensional viscosities even though the overall bond kinetics and equilibrium constant remain unchanged. Increased dissipation in the simulations is primarily due to higher average chain extension with increasing bond number. These results indicate that toughness and dissipation in physically associating networks can both be increased by breaking single, strong bonds into smaller components.
Measurement of sliding friction coefficient of micro-line patterned surfaces on ice
Authors: Kim Sangmyeong , Kang Hosung , Kim Dohyung , Lee Young-Ze , Lee Jinkee
Published: November 2017

Although the sliding friction of patterned surfaces on ice has been investigated for over a century, physical analysis still needs to be improved. In this study, we investigate the friction coefficient on ice by changing the experimental conditions of temperature, gap between line patterns (20 μm and 200 μm), and sliding direction. In the temperature region of −17.7 °C < T <−2.5 °C, a longer gap (200 μm) patterned surface has a lower friction coefficient for both parallel and perpendicular sliding directions at the same temperatures. Interestingly, a lower friction coefficient is found when the sliding direction is perpendicular to the micro-structure patterns at T < −7.6 °C for gap = 20 μm and at T < −9.9 °C for gap = 200 μm. To understand this interesting phenomenon, a theoretical model is derived by modifying the model from the study by Oksanen and Keinonen. Based on this modified model, the surface with a shorter gap (20 μm) makes fewer contacts and the pattern direction determines the water layer elongation at each contact. This validates that friction on ice can be controlled using a micro-structure pattern and moreover suggests a method for finding an optimized micro-structured surface for reducing friction on ice.
Production and aging of paramagnetic point defects in P-doped floating zone silicon irradiated with high fluence 27 MeV electrons
Authors: Joita A. C. , Nistor S. V.
Published: November 2017

Enhancing the long term stable performance of silicon detectors used for monitoring the position and flux of the particle beams in high energy physics experiments requires a better knowledge of the nature, stability, and transformation properties of the radiation defects created over the operation time. We report the results of an electron spin resonance investigation in the nature, transformation, and long term stability of the irradiation paramagnetic point defects (IPPDs) produced by high fluence (2 × 1016 cm−2), high energy (27 MeV) electrons in n-type, P-doped standard floating zone silicon. We found out that both freshly irradiated and aged (i.e., stored after irradiation for 3.5 years at 250 K) samples mainly contain negatively charged tetravacancy and pentavacancy defects in the first case and tetravacancy defects in the second one. The fact that such small cluster vacancy defects have not been observed by irradiation with low energy (below 5 MeV) electrons, but were abundantly produced by irradiation with neutrons, strongly suggests the presence of the same mechanism of direct formation of small vacancy clusters by irradiation with neutrons and high energy, high fluence electrons, in agreement with theoretical predictions. Differences in the nature and annealing properties of the IPPDs observed between the 27 MeV electrons freshly irradiated, and irradiated and aged samples were attributed to the presence of a high concentration of divacancies in the freshly irradiated samples, defects which transform during storage at 250 K through diffusion and recombination processes.
Robust nano-fabrication of an integrated platform for spin control in a tunable microcavity
Authors: Bogdanović Stefan , Liddy Madelaine S. Z. , van Dam Suzanne B. , Coenen Lisanne C. , Fink Thomas , Lončar Marko , Hanson Ronald
Published: November 2017

Coupling nitrogen-vacancy (NV) centers in diamonds to optical cavities is a promising way to enhance the efficiency of diamond-based quantum networks. An essential aspect of the full toolbox required for the operation of these networks is the ability to achieve the microwave control of the electron spin associated with this defect within the cavity framework. Here, we report on the fabrication of an integrated platform for the microwave control of an NV center electron spin in an open, tunable Fabry–Pérot microcavity. A critical aspect of the measurements of the cavity’s finesse reveals that the presented fabrication process does not compromise its optical properties. We provide a method to incorporate a thin diamond slab into the cavity architecture and demonstrate the control of the NV center spin. These results show the promise of this design for future cavity-enhanced NV center spin-photon entanglement experiments.
Lifetime and universal distribution of seed runaway electrons
Authors: Fontanilla Adrian K. , Breizman Boris N.
Published: November 2017

The lifetime of pre-existing runaway electrons determines how likely the runaways will undergo avalanche multiplication. We estimate the lifetime of runaway electrons via kinetic analysis. We show that the rate of runaway decay depends on the combination of parameters α≡(Z+1)/τ¯rad (where τ¯rad is the synchrotron timescale normalized to the collisional timescale and Z is the ion charge) compared to the electric field. We identify two cases where the decay rate is slow enough to enable a quasi-steady shape of the runaway distribution function. This distribution and its lifetime represent the eigenfunction and the lowest eigenvalue of the kinetic equation. In one case, α≪1: the field required to sustain the pre-existing runaways is barely larger than the Connor-Hastie critical value. In the same manner as by Aleynikov and Breizman [Phys. Rev. Lett. 114, 155001 (2015)], we solve the kinetic equation perturbatively but extend the work to demonstrate that the lifetime grows exponentially with the field at a rate that depends on α. In the second case, α≫1: the sustainment field is much greater than the Connor-Hastie value, and the largeness of the field in this case enables us to universalize the kinetic equation via the re-scaling procedure.
Correlation analysis between the current fluctuation characteristics and the conductive filament morphology of HfO2-based memristor
Authors: Li Yi , Yin Kang-Sheng , Zhang Mei-Yun , Cheng Long , Lu Ke , Long Shi-Bing , Zhou Yaxiong , Wang Zhuorui , Xue Kan-Hao , Liu Ming , Miao Xiang-Shui
Published: November 2017

Memristors are attracting considerable interest for their prospective applications in nonvolatile memory, neuromorphic computing, and in-memory computing. However, the nature of resistance switching is still under debate, and current fluctuation in memristors is one of the critical concerns for stable performance. In this work, random telegraph noise (RTN) as the indication of current instabilities in distinct resistance states of the Pt/Ti/HfO2/W memristor is thoroughly investigated. Standard two-level digital-like RTN, multilevel current instabilities with non-correlation/correlation defects, and irreversible current transitions are observed and analyzed. The dependence of RTN on the resistance and read bias reveals that the current fluctuation depends strongly on the morphology and evolution of the conductive filament composed of oxygen vacancies. Our results link the current fluctuation behaviors to the evolution of the conductive filament and will guide continuous optimization of memristive devices.
Influence of interface inhomogeneities in thin-film Schottky diodes
Authors: Wilson Joshua , Zhang Jiawei , Li Yunpeng , Wang Yiming , Xin Qian , Song Aimin
Published: November 2017

The scalability of thin-film transistors has been well documented, but there have been very few investigations into the effects of device scalability in Schottky diodes. Indium-gallium-zinc-oxide (IGZO) Schottky diodes were fabricated with IGZO thicknesses of 50, 150, and 250 nm. Despite the same IGZO-Pt interface and Schottky barrier being formed in all devices, reducing the IGZO thickness caused a dramatic deterioration of the current-voltage characteristics, most notably increasing the reverse current by nearly five orders of magnitude. Furthermore, the forward characteristics display an increase in the ideality factor and a reduction in the barrier height. The origins of this phenomenon have been elucidated using device simulations. First, when the semiconductor layer is fully depleted, the electric field increases with the reducing thickness, leading to an increased diffusion current. However, the effects of diffusion only offer a small contribution to the huge variations in reverse current seen in the experiments. To fully explain this effect, the role of inhomogeneities in the Schottky barrier height has been considered. Contributions from lower barrier regions (LBRs) are found to dominate the reverse current. The conduction band minimum below these LBRs is strongly dependent upon thickness and bias, leading to reverse current variations as large as several orders of magnitude. Finally, it is demonstrated that the thickness dependence of the reverse current is exacerbated as the magnitude of the inhomogeneities is increased and alleviated in the limit where the LBRs are large enough not to be influenced by the adjacent higher barrier regions.
Uniformity of cylindrical imploding underwater shockwaves at very small radii
Authors: Yanuka D. , Rososhek A. , Bland S. N. , Krasik Ya. E.
Published: November 2017

We compare the convergent shockwaves generated from underwater, cylindrical arrays of copper wire exploded by multiple kilo-ampere current pulses on nanosecond and microsecond scales. In both cases, the pulsed power devices used for the experiments had the same stored energy (∼500 J) and the wire mass was adjusted to optimize energy transfer to the shockwave. Laser backlit framing images of the shock front were achieved down to the radius of 30 μm. It was found that even in the case of initial azimuthal non-symmetry, the shock wave self-repairs in the final stages of its motion, leading to a highly uniform implosion. In both these and previous experiments, interference fringes have been observed in streak and framing images as the shockwave approached the axis. We have been able to accurately model the origin of the fringes, which is due to the propagation of the laser beam diffracting off the uniform converging shock front. The dynamics of the shockwave and its uniformity at small radii indicate that even with only 500 J stored energies, this technique should produce pressures above 1010 Pa on the axis, with temperatures and densities ideal for warm dense matter research.
Removing the current-limit of vertical organic field effect transistors
Authors: Sheleg Gil , Greenman Michael , Lussem Bjorn , Tessler Nir
Published: November 2017

The reported Vertical Organic Field Effect Transistors (VOFETs) show either superior current and switching speeds or well-behaved transistor performance, especially saturation in the output characteristics. Through the study of the relationship between the device architecture or dimensions and the device performance, we find that achieving a saturation regime in the output characteristics requires that the device operates in the injection limited regime. In current structures, the existence of the injection limited regime depends on the source's injection barrier as well as on the buried semiconductor layer thickness. To overcome the injection limit imposed by the necessity of injection barrier, we suggest a new architecture to realize VOFETs. This architecture shows better gate control and is independent of the injection barrier at the source, thus allowing for several A cm−2 for a semiconductor having a mobility value of 0.1 cm2 V−1 s−1.
Noise performance of PbS colloidal quantum dot photodetectors
Authors: De Iacovo A. , Venettacci C. , Colace L. , Scopa L. , Foglia S.
Published: November 2017

We report on the noise characterization of photoconductors based on PbS colloidal quantum dots. The devices operate in the near infrared region with peak responsivity exceeding 70 A/W at 1.3 μm at low optical intensity and low voltage bias. The large responsivity, combined with the low dark current of high resistance devices, provides a specific detectivity D* as large as 1011 cm Hz1/2 W−1. The noise characteristics are investigated using noise current spectra measured at different biases both in dark and under optical excitation. The analysis revealed that the noise is clearly dominated by the flicker component up to 100 kHz. The noise performance is investigated at different optical intensities and for different device dimensions and voltage biases.
Shockwave-assisted laser filament conductivity
Authors: Schubert Elise , Mongin Denis , Produit Thomas , Schimmel Guillaume , Kasparian Jérôme , Wolf Jean-Pierre
Published: November 2017

We investigate the influence of ultrashort laser filaments on high-voltage discharges and spark-free unloading at various repetition rates and wind conditions. For electric fields well below, close to, and above the threshold for discharges, we observe remote spark-free unloading, discharge suppression, and discharge guiding, respectively. These effects rely on an indirect consequence of thermal deposition, namely, the fast dilution of ions by the shockwave triggered by the filament at each laser shot. This dilution drastically limits ion-ion recombination and increases the plasma channel conductivity that can still be non-negligible after tens or hundreds of milliseconds. As a result, the charge flow per pulse is higher at low repetition rates.
Minimax method involving singular p(x)-Kirchhoff equation
Authors: Ben Ali K. , Ghanmi A. , Kefi K.
Published: November 2017

Using a variational approach combined with the theory of the generalized Lebesgue-Sobolev spaces, we obtain at least one weak solution for a class of p(x)-Kirchhoff singular equations.
Mixing properties of tree-shifts
Authors: Ban Jung-Chao , Chang Chih-Hung
Published: November 2017

The uncertainty of multidimensional shift spaces draws attracted attention of researchers. For example, the emptiness problem is undecidable; there exist aperiodic shifts of finite type; there is a nonempty shift of finite type exhibiting nonextensible local patterns. This paper investigates symbolic dynamics on Cayley trees and gives affirmative answers to the above questions in tree-shifts. Beyond that, with introducing block gluing tree-shift, a sufficient condition of exhibiting positive topological entropy is revealed.
Study on the streamer inception characteristics under positive lightning impulse voltage
Authors: Wang Zezhong , Geng Yinan
Published: November 2017

The streamer is the main process in an air gap discharge, and the inception characteristics of streamers have been widely applied in engineering. Streamer inception characteristics under DC voltage have been studied by many researchers, but the inception characteristics under impulse voltage, and particularly under lightning impulse voltage with a high voltage rise rate have rarely been studied. A measurement system based on integrated optoelectronic technology has been proposed in this paper, and the streamer inception characteristics in a 1-m-long rod-plane air gap that was energized by a positive lightning impulse voltage have been researched. We have also measured the streamer inception electric field using electrodes with different radii of curvature and different voltage rise rates. As a result, a modified empirical criterion for the streamer inception electric field that considers the voltage rise rate has been proposed, and the wide applicability of this criterion has been proved. Based on the streamer inception time-lag obtained, we determined that the field distribution obeys a Rayleigh distribution, which explains the change law of the streamer inception time-lag. The characteristic parameter of the Rayleigh distribution lies in the range from 0.6 to 2.5 when the radius of curvature of the electrode head is in the range from 0.5 cm to 2.5 cm and the voltage rise rate ranges from 80 kV/μs to 240kV/μs under positive lightning impulse voltage.