bluuebunny/crossref_metadata_2025 huggingface dataset:
Glutenfreie Ernährung – eine Trend-Diät?
Authors: Maurer Bianca
Published: June 2019

Lady Gaga, Miley Cyrus und Gwyneth Paltrow – sie alle haben eines gemeinsam: Sie
haben glutenhaltige Lebensmittel von ihrem Speiseplan gestrichen. Eine Zöliakie
oder andere medizinische Gründe für die strenge Diät sind bei keiner dieser
Prominenten bekannt. Man fühle sich ohne Gluten besser, die glutenfreie
Ernährung habe positive Effekte auf Haut und Gesundheit – diese und ähnliche
Gründe werden für den Verzicht angegeben.
Interventionsassoziierte Myokardischämie: intrakoronare Bildgebung als prognostischer Marker
Authors: Anadol Remzi , Gori Tommaso
Published: June 2019

Die interventionsassoziierte Myokardischämie ist mit einem erhöhten Risiko für ein negatives Outcome verbunden. Der Nachweis bestimmter Pathologien, wie z. B. ein Fibroatherom mit zum Lumen hin dünner Endothelschicht (thin-cap fibrous atheroma) in der optischen Kohärenztomografie (OCT) oder im intravaskulären Ultraschall (IVUS) sind prädiktiv für eine periprozedurale Myokardischämie. Die Nutzung dieser Methoden und die korrekte Interpretation während der Indexprozedur und im weiteren klinischen Verlauf können für den Patienten eine bessere Risikostratifizierung und eine an ihn angepassten Therapie bedingen.
Nachsorge ‚Neues Credo‘ in der kardiologischen
Anschlussrehabilitation
Authors: Deck Ruth , Beitz Sebastian , Baumbach Christian , Brunner Susanne , Hoberg Eike , Knoglinger Ernst
Published: June 2019

Ziel der Studie Körperliche Inaktivität gilt als
wichtigster modifizierbarer Risikofaktor für kardiovaskuläre
Erkrankungen, daher fokussiert die medizinische Rehabilitation v. a. auf
die Steigerung der körperlichen Aktivität. Damit diese nach der
Rehabilitation aufrechterhalten wird, sind Nachsorgestrategien erforderlich, die
den Rehabilitand/innen den Transfer des in der Rehabilitation Gelernten
in den Alltag erleichtern. In vorliegender Studie wurde das mehrfach evaluierte
Nachsorgekonzept „Neues Credo“ in der kardiologischen
Anschlussrehabilitation eingeführt und evaluiert.

Methodik Prospektive, kontrollierte, multizentrische Studie mit 4
kardiologischen Reha-Einrichtungen. Einschlusskriterien:
Rehabilitand/ innen mit einer Erstdiagnose aus der ICD-Gruppe
I20–25, I34–43. Rehabilitand/innen der Kontrollgruppe
(KG) führten zunächst eine Standardrehabilitation und
Standardnachsorge durch, danach die Rehabilitand/ innen der
Interventionsgruppe (IG) eine Rehabilitation nach den Prämissen des
Neuen Credo mit dem Schwerpunkt Steigerung körperlicher
Aktivität. Die IG erhielt hierfür verschiedene
Dokumentationshefte. Die Evaluation erfolgte durch schriftliche Befragung zu 3
Messzeitpunkten. Primäre Zielgröße:
Einschränkungen der Teilhabe (IMET), sekundäre
Zielgrößen: u. a. Depressivität (CES-D) und
verschiedene Skalen der subjektiven Gesundheit sowie Ausmaß der
körperlichen Aktivität. Die Auswertung der Langzeiteffekte
erfolgte mithilfe von Varianzanalysen mit Messwiederholung.

Ergebnisse Von 152 Rehabilitand/innen der IG und 165
Rehabilitand/innen der KG konnten die kompletten Daten ausgewertet
werden. Am Ende der Reha profitierten sowohl IG als auch KG von der
Rehabilitation. Im Katamnesezeitraum erreichten die Teilnehmer der IG
signifikant häufiger das Ziel, ihre körperliche
Aktivität zu steigern (66 vs. 42%, p<0,01), sie waren
häufiger körperlich aktiv als die KG (p=0,040) und sie
trieben signifikant häufiger Ausdauersport (58 vs. 38%,
p<0,01). Zwölf Monate nach der Rehabilitation sind für
beide Gruppen signifikante Verbesserungen im primären Outcome Teilhabe
festzustellen (p<0,01), der Unterschied zwischen den Gruppen erreichte
zwar keine statistische Signifikanz, allerdings bestand eine klare Tendenz
zugunsten der IG. Ähnliche Verläufe zeigen sich bei den meisten
sekundären Zielgrößen.

Schlussfolgerung Das Neue Credo wurde erstmals in der kardiologischen
Anschlussrehabilitation erprobt und evaluiert. Die große Mehrheit der
Beteiligten berichteten eine hohe Praktikabilität und eine hohe
Zufriedenheit. Hinsichtlich der gesundheitsbezogenen Outcomes ergaben sich
Hinweise auf positive Effekte, die zugunsten der IG ausfielen, allerdings
erreichten die Interaktionseffekte in den meisten Fällen keine
statistische Signifikanz. Bei der Zielgröße Steigerung der
körperlichen Aktivität ist die Interventionsgruppe klar im
Vorteil und profitiert vermutlich auch längerfristig von den Effekten
des regelmäßigen Ausdauertrainings.
Adjunctive Reboxetine for Schizophrenia: Meta-analysis of Randomized Double-blind, Placebo-controlled Trials
Authors: Zheng Wei , Li Xian-Bin , Shi Zhan-Ming , Yang Xin-Hu , Cai Dong-Bin , Ng Chee H. , Ungvari Gabor S. , Liu Wei-Jian , Wu Yu-Jie , Wang Yuan-Yuan , Ning Yu-Ping , Xiang Yu-Tao
Published: June 2019

Background Results of previous studies on the safety and efficacy of adjunctive reboxetine for schizophrenia have been inconsistent.

Aim The aim of this study was to examine the efficacy and tolerability of reboxetine as an adjunct medication to antipsychotic treatment in a meta-analysis of randomized controlled trials (RCTs).

Methods Two independent investigators extracted data for a random effects meta-analysis and assessed the quality of studies using risk of bias and the Jadad scale. Weighted and standardized mean differences (WMDs/SMDs) and risk ratio (RR)±95% confidence intervals (CIs) were calculated.

Results Nine RCTs (n=630) with double-blind design were identified. Reboxetine outperformed placebo in improving negative (9 RCTs, n=602, SMD: −0.47 [95% CI: −0.87, −0.07], p=0.02; I2=82%), but not the overall, positive, and general psychopathology scores. The significant therapeutic effect on negative symptoms disappeared in the sensitivity analysis after removing an outlying study and in 50% (6/12) of the subgroup analyses. Reboxetine outperformed placebo in reducing weight (3 RCTs, n=186, WMD: −3.83 kg, p=0.04; I2=92%) and body mass index (WMD: −2.23 kg/m2, p=0.04; I2=95%). Reboxetine caused dry mouth but was associated with less weight gain overall and weight gain of ≥7% of the initial weight. All-cause discontinuation and other adverse events were similar between reboxetine and placebo.

Conclusion Adjunctive reboxetine could be useful for attenuating antipsychotic-induced weight gain, but it was not effective in treating psychopathology including negative symptoms in schizophrenia.
Metabolic Profiling of Saponin-Rich Ophiopogon japonicus Roots Based on 1H NMR and HPTLC Platforms
Authors: Ge Yanhui , Chen Xiaojia , Gođevac Dejan , Bueno Paula C. P. , Salomé Abarca Luis F. , Jang Young Pyo , Wang Mei , Choi Young Hae
Published: June 2019

Ideally, metabolomics should deal with all the metabolites that are found within cells and biological systems. The most common technologies for metabolomics include mass spectrometry, and in most cases, hyphenated to chromatographic separations (liquid chromatography- or gas chromatography-mass spectrometry) and nuclear magnetic resonance spectroscopy. However, limitations such as low sensitivity and highly congested spectra in nuclear magnetic resonance spectroscopy and relatively low signal reproducibility in mass spectrometry impede the progression of these techniques from being universal metabolomics tools. These disadvantages are more notorious in studies of certain plant secondary metabolites, such as saponins, which are difficult to analyse, but have a great biological importance in organisms. In this study, high-performance thin-layer chromatography was used as a supplementary tool for metabolomics. A method consisting of coupling 1H nuclear magnetic resonance spectroscopy and high-performance thin-layer chromatography was applied to distinguish between Ophiopogon japonicus roots that were collected from two growth locations and were of different ages. The results allowed the root samples from the two growth locations to be clearly distinguished. The difficulties encountered in the identification of the marker compounds by 1H nuclear magnetic resonance spectroscopy was overcome using high-performance thin-layer chromatography to separate and isolate the compounds. The saponins, ophiojaponin C or ophiopogonin D, were found to be marker metabolites in the root samples and proved to be greatly influenced by plant growth location, but barely by age variation. The procedure used in this study is fully described with the purpose of making a valuable contribution to the quality control of saponin-rich herbal drugs using high-performance thin-layer chromatography as a supplementary analytical tool for metabolomics research.
Ostomy Complications in Crohn's Disease
Authors: Aboulian Armen
Published: June 2019

Ostomy creation is a routine surgical procedure that has earned its place high in the surgeon's armamentarium in dealing with challenging situations. However, it is not without its complications. In this article, we review the common complications including parastomal hernia, prolapse, mucocutaneous junction separation with ischemia and stenosis, peristomal skin conditions, and infections. Additionally, we review conditions that arise in association with underlying Crohn's disease, such as peristomal inflammation, fistula formation, and pyoderma gangrenosum.
Integrales Supply Chain Management im Krankenhaus: In Wertschöpfungsketten Denken
Authors: Kriegel Johannes
Published: June 2019

Patientenorientierung, Innovationen in Diagnostik und Therapie, Spezialisierung und Fachkräftemangel erfordern eine Hinwendung zur ablauf- und ergebnisorientierten Systemausrichtung. Ganzheitliche strategische Orientierung und logistische Gestaltungsansätze ermöglichen eine zielgerichtete und ressourcenoptimierte Patientenversorgung.
Erfahrungsbericht: Ein Logistischer Meilenstein
Authors: Brandstetter Jacqueline
Published: June 2019

Prozessvielfalt, Leistungsspektrum und Kundenorientierung im Krankenhaus erfordern gesteuerte und vernetzte Patienten- und Warenströme. Die Niederösterreichische Landeskliniken Holding optimiert und professionalisiert die Unterstützungsprozesse über eine zentralisierte Krankenhauslogistik und logistisches Management.
EU-MDR: Was Sich mit dem Ende der Übergangsfrist für den Einkauf ändert
Authors: Osterhues Heiner
Published: June 2019

Die neue europäische Medizinprodukte-Verordnung fasst die zwei bisherigen Richtlinien zusammen und ersetzt sie; als europäische Verordnung gilt sie auch für Deutschland. Für den Einkauf bedeutet das: Mit Ablauf der Übergangsfristen muss man mit Versorgungsengpässen bestimmter Produkte und mit Kostensteigerungen rechnen.
Application of transformation optics in radar cross section reduction of targets with arbitrary two-dimensional geometries
Authors: Fakheri Mohammad Hosein , Abdolali Ali
Published: June 2019

Transformation optics (TO) provides an unconventional approach to control electromagnetic (EM) waves in an arbitrary manner. In this study, a new strategy of radar cross section reduction (RCSR) was proposed for two-dimensional (2D) targets of arbitrary shape. Applying a complex coordinate transformation allowed us to control both the amplitude and the phase of EM fields. Inspired by the black hole concept, a swampy coating layer (SCL) was designed to make EM fields spin around the target and dissipate gradually. To achieve this goal, a complex Archimedean coordinate transformation function was exploited. This forced the incoming EM waves to propagate on a lossy path that was longer than the conventional radar absorbing materials (RAMs). Hence, it provided sufficient time for the SCL to dissipate the trapped EM wave. Depending on the target size, the SCL materials were analytically derived based on the coordinate transformation theory. However, these materials are feasibly independent of the target geometry and its constitutive materials. Several examples were provided to highlight the capability of the proposed TO-based strategy. This method reduced the radar cross section of 2D targets with irregular geometries and different materials. Numerical simulations were carried out to verify the feasibility of design by using a composite of the split ring resonator-meander line array. A significant RCSR level was noticed whose operating bandwidth was dictated by the employed metamaterial unit cell. So, the simplicity of the design sacrificed the RCSR bandwidth. Therefore, this paper revealed a new class of TO-based RAMs for 2D arbitrary-geometry targets of different materials.
Nuclear dynamics in resonant inelastic X-ray scattering and X-ray absorption of methanol
Authors: Vaz da Cruz Vinícius , Ignatova Nina , Couto Rafael C. , Fedotov Daniil A. , Rehn Dirk R. , Savchenko Viktoriia , Norman Patrick , Ågren Hans , Polyutov Sergey , Niskanen Johannes , Eckert Sebastian , Jay Raphael M. , Fondell Mattis , Schmitt Thorsten , Pietzsch Annette , Föhlisch Alexander , Gel’mukhanov Faris , Odelius Michael , Kimberg Victor
Published: June 2019

We report on a combined theoretical and experimental study of core-excitation spectra of gas and liquid phase methanol as obtained with the use of X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS). The electronic transitions are studied with computational methods that include strict and extended second-order algebraic diagrammatic construction [ADC(2) and ADC(2)-x], restricted active space second-order perturbation theory, and time-dependent density functional theory—providing a complete assignment of the near oxygen K-edge XAS. We show that multimode nuclear dynamics is of crucial importance for explaining the available experimental XAS and RIXS spectra. The multimode nuclear motion was considered in a recently developed “mixed representation” where dissociative states and highly excited vibrational modes are accurately treated with a time-dependent wave packet technique, while the remaining active vibrational modes are described using Franck–Condon amplitudes. Particular attention is paid to the polarization dependence of RIXS and the effects of the isotopic substitution on the RIXS profile in the case of dissociative core-excited states. Our approach predicts the splitting of the 2a″ RIXS peak to be due to an interplay between molecular and pseudo-atomic features arising in the course of transitions between dissociative core- and valence-excited states. The dynamical nature of the splitting of the 2a″ peak in RIXS of liquid methanol near pre-edge core excitation is shown. The theoretical results are in good agreement with our liquid phase measurements and gas phase experimental data available from the literature.
Phase-field simulations on the electrocaloric properties of ferroelectric nanocylinders with the consideration of surface polarization effect
Authors: Zhu Jun , Chen Haoyun , Hou Xu , Xu Linrong , Wu Huaping , Wang Jie
Published: June 2019

Due to the symmetry breaking on surfaces of a ferroelectric crystal, the polarizations on surfaces are different from those inside the crystal. To describe this surface polarization effect which depends on the surface atomic termination, the extrapolation length is incorporated in the phase-field method based on the time-dependent Ginzburg-Landau equation to investigate different surface polarizations and their influence on the electrocaloric properties in PbTiO3 nanocylinders. The simulation results show that the extrapolation length can alter the maximum value of the adiabatic temperature change and shift its temperature location.
Mixture domain states in PbTiO3 film with potentials for functional application
Authors: Xu Han , Zhang Zhan , Dong Yongqi , Zeng Changgan , Fong Dillon D. , Luo Zhenlin
Published: June 2019

We investigated the microstructure of PbTiO3 films epitaxially grown on DyScO3 (110) substrates using synchrotron-based 3D reciprocal space mapping and X-ray reflection interface microscopy. The results show that an in-plane anisotropic mixture domain state (a* + a/c) exists in the PbTiO3 films, where a* domains reside between a/c twin stripe domains. Furthermore, when compared with traditional a domains in a/c twins, the a* domain is found to possess a similar in-plane lattice parameter but a much smaller out-of-plane lattice (∼0.5%). We also discovered a temperature-driven transition between a* and a/c pointing to potential applications in functional devices due to the huge mechanical response (4.85%) and polarization rotation between the a* and c domains.
Electron mobility enhancement in an undoped Si/SiGe heterostructure by remote carrier screening
Authors: Su Yi-Hsin , Chou Kuan-Yu , Chuang Yen , Lu Tzu-Ming , Li Jiun-Yun
Published: June 2019

We investigate the effects of surface tunneling on electrostatics and transport properties of two-dimensional electron gases (2DEGs) in undoped Si/SiGe heterostructures with different 2DEG depths. By varying the gate voltage, four stages of density-mobility dependence are identified with two density saturation regimes observed, which confirms that the system transitions between equilibrium and nonequilibrium. Mobility is enhanced with an increasing density at low biases and, counterintuitively, with a decreasing density at high biases as well. The density saturation and mobility enhancement can be semiquantitatively explained by a surface tunneling model in combination with a bilayer screening theory.
Interactions of benzene, naphthalene, and azulene with alkali-metal and alkaline-earth-metal atoms for ultracold studies
Authors: Wójcik Paweł , Korona Tatiana , Tomza Michał
Published: June 2019

We consider collisional properties of polyatomic aromatic hydrocarbon molecules immersed into ultracold atomic gases and investigate intermolecular interactions of exemplary benzene, naphthalene, and azulene with alkali-metal (Li, Na, K, Rb, and Cs) and alkaline-earth-metal (Mg, Ca, Sr, and Ba) atoms. We apply the state-of-the-art ab initio techniques to compute the potential energy surfaces (PESs). We use the coupled cluster method restricted to single, double, and noniterative triple excitations to reproduce the correlation energy and the small-core energy-consistent pseudopotentials to model the scalar relativistic effects in heavier metal atoms. We also report the leading long-range isotropic and anisotropic dispersion and induction interaction coefficients. The PESs are characterized in detail, and the nature of intermolecular interactions is analyzed and benchmarked using symmetry-adapted perturbation theory. The full three-dimensional PESs are provided for the selected systems within the atom-bond pairwise additive representation and can be employed in scattering calculations. The present study of the electronic structure is the first step toward the evaluation of prospects for sympathetic cooling of polyatomic aromatic molecules with ultracold atoms. We suggest azulene, an isomer of naphthalene which possesses a significant permanent electric dipole moment and optical transitions in the visible range, as a promising candidate for electric field manipulation and buffer-gas or sympathetic cooling.
Large-eddy simulation of an open-channel flow bounded by a semi-dense rigid filamentous canopy: Scaling and flow structure
Authors: Monti A. , Omidyeganeh M. , Pinelli A.
Published: June 2019

We have carried out a large-eddy simulation of a turbulent open-channel flow over a marginally dense, fully submerged, rigid canopy. The canopy is made of a set of rigid, slender cylinders normally mounted on a solid wall. The flow in the canopy is resolved stem-by-stem by means of an immersed boundary method. It is found that the flow behavior can be categorized according to the velocity distribution into two separate spatial regions: the canopy itself and the outer region above it. Within the region occupied by the canopy elements, the velocity magnitude is found to be related to the local shear stress. Outside the canopy, a logarithmic velocity profile matching the canonical turbulent open-channel flow over rough walls is recovered albeit the strong manipulation exerted by the canopy on the buffer layer. In the innermost layer, the presence of the stems is responsible for redistributing the local momentum fluctuations from a streamwise to a spanwise leading component, inhibiting the survival of the wall streamwise velocity streaks. On the other hand, the outer region presents a structure very similar to the well-known logarithmic boundary layer with the presence of large and energetic streamwise velocity streaks generated by a system of quasistreamwise vortices. These vortices strongly contribute to the intracanopy fluctuations through vigorous sweep and ejection events that affect all the region occupied by the stems. Consistent with the results of previous investigations [H. Nepf, “Flow and transport in regions with aquatic vegetation,” Annu. Rev. Fluid Mech. 44, 123–142 (2012)], it is found that the inflection point in the mean velocity profile, produced by the drag discontinuity at the canopy tip, promotes the appearance of another system of spanwise oriented vorticity structures. However, different from previous results reported in the literature [J. Finnigan, “Turbulence in plant canopies,” Annu. Rev. Fluid Mech. 32, 519–571 (2000)], in our simulations, the presence of alternating head up–head down hairpin vortices generated by a mutual induction of the counter-rotating spanwise vortices is not observed. Instead, we advocate that the modulation of the spanwise coherent vorticity is due to the action of the external logarithmic layer structures (i.e., the outer streamwise vortices that penetrate the canopy) rather than by upwash and downwash motions induced by the mutual interaction of the spanwise rollers.
Thermal atomic layer etching of crystalline GaN using sequential exposures of XeF2 and BCl3
Authors: Johnson Nicholas R. , Hite Jennifer K. , Mastro Michael A. , Eddy Charles. R. , George Steven M.
Published: June 2019

Gallium nitride (GaN) is a wide-bandgap semiconductor that is useful for optoelectronics and high speed and high power electronics. Fabrication of GaN devices requires etching for many processing steps. Gas phase thermal atomic-layer-controlled etching is desirable for damage-free isotropic etching. In this letter, the thermal atomic layer etching (ALE) of crystalline GaN was demonstrated using sequential exposures of XeF2 and BCl3. GaN ALE was achieved with an etch rate of 0.55 Å/cycle at 195 °C using XeF2 exposures for 20 s at 40 mTorr and BCl3 exposures for 0.5 s at 50 mTorr. At the same reactant exposures, GaN etch rates varied with temperature from 0.18 Å/cycle at 170 °C to 0.72 Å/cycle at 300 °C. The GaN etch rates increased slowly with increasing XeF2 exposure. In addition, the GaN etch rate was self-limiting with respect to both increasing BCl3 pressures and BCl3 exposure times. This self-limiting behavior for BCl3 is consistent with a ligand-exchange mechanism for GaN ALE. Alternative fluorination reactants were also investigated including HF, SF4, and NF3 plasma. Sequential exposures of NF3 plasma and BCl3 yielded GaN etch rates of 2.5–2.9 Å/cycle at 250 °C. In contrast, the HF and SF4 fluorination reactants could not etch crystalline GaN.
Electron Bessel beam diffraction for precise and accurate nanoscale strain mapping
Authors: Guzzinati Giulio , Ghielens Wannes , Mahr Christoph , Béché Armand , Rosenauer Andreas , Calders Toon , Verbeeck Jo
Published: June 2019

Strain has a strong effect on the properties of materials and the performance of electronic devices. Their ever shrinking size translates into a constant demand for accurate and precise measurement methods with a very high spatial resolution. In this regard, transmission electron microscopes are key instruments thanks to their ability to map strain with a subnanometer resolution. Here, we present a method to measure strain at the nanometer scale based on the diffraction of electron Bessel beams. We demonstrate that our method offers a strain sensitivity better than 2.5 × 10−4 and an accuracy of 1.5 × 10−3, competing with, or outperforming, the best existing methods with a simple and easy to use experimental setup.
Excitation wavelength-dependent carrier dynamics in n-type and semi-insulating 6H-SiC using ultrafast transient absorption spectroscopy
Authors: Fang Yu , Nie Yao , Wu Xingzhi , Yang Junyi , Chen Yongqiang , Wang Youyun , Wu Quanying , Song Yinglin
Published: June 2019

Transient absorption spectroscopy was utilized to monitor ultrafast carrier dynamics in conductive and semi-insulating 6H-SiC wafers. By tuning the excitation wavelength around the bandgap of 6H-SiC (365–400 nm), the surface and bulk recombination processes could be accordingly distinguished. Simultaneously, the locations of surface and defect states in the bandgap were inferred by investigating the evolution of transient absorption spectra for different photoexcited carrier distributions. Vanadium (V) doping had a notable modulation on transient absorption in semi-insulating 6H-SiC, resulting from an additional decay process induced by carrier capturing of V deep levels. The carrier lifetimes induced by various recombination mechanisms were determined and interpreted unequivocally by global analysis and simplified model. The time constant via bulk capturing (∼400 ps) was three orders of magnitude faster than that via inherent defects. Controlling the lifetime by excitation wavelength and doping conditions is essential for fabricating 6H-SiC-based ultrafast photonic devices.
Exact open quantum system dynamics: Optimal frequency vs time representation of bath correlations
Authors: Hartmann Richard , Werther Michael , Grossmann Frank , Strunz Walter T.
Published: June 2019

Two different numerically exact methods for open quantum system dynamics, the hierarchy of pure states (HOPS) method, and the multi-Davydov-Ansatz are discussed. We focus on the suitability of the underlying representations of bath correlations. While in the HOPS case the correct description of the bath correlation function (BCF) in the time domain is decisive, it turns out that a windowed Fourier transform of the BCF is an appropriate indicator of the quality of the discretization in the multi-Davydov-Ansatz. For the spin-boson model with sub-Ohmic spectral density considered here, a discretization of the spectral density based on an exponential distribution, used previously, turns out to be most favorable.
Ultrafast measurements of ion temperature in high-energy-density plasmas by nuclear resonance fluorescence
Authors: Yu Yong , Shen Baifei
Published: June 2019

Doppler broadening of characteristic emission lines by nuclear resonance fluorescence (NRF) is proposed as an ultrafast method for actively measuring the ion temperature in plasmas. For 6Li plasmas with an areal density of 1 g cm−2 and an ion temperature of 10 keV, a collimated ultrafast gamma-ray pulse with a spectral density of 100 photons/keV at a resonance energy of 3.56 MeV can generate one NRF photon and has an emission spectral width of approximately 6 keV. This method provides a new experimental tool for high-energy-density physics, including inertial confinement fusion and experimental astrophysics.
Hydrated excess protons and their local hydrogen bond transport network as measured by translational, librational, and vibrational frequencies
Authors: Teschke Omar , de Castro Jose Roberto , Gomes Wyllerson Evaristo , Soares David Mendez
Published: June 2019

A clear molecular description of excess hydrated protons and their local hydrogen bond transport network remains elusive. Here, the hydrogen bond network of excess hydrated protons in water bridges was probed by measuring their Raman spectra and comparing them to the spectra of protons in ice and water. The proton vibrational spectrum and the hydrogen bond network translational and librational spectra were recorded. The spectra of the water bridge and water exhibit clear differences, indicating the presence of a structure in water bridges when subjected to an electric field of ∼106 V/m that has not been previously reported. The intermolecular Raman spectrum of the floating water bridge exhibits a hydrogen bond stretching band at 150–250 cm−1, librational bands within the 300–1000 cm−1 spectral range, and a large band at 1500–3000 cm−1, which corresponds to the vibrational signature of excess hydrated protons in the water bridge structure. The excess protons are shown to move predominantly at the air/water interface, and the effect of this distribution is a measurable change in the air/water interfacial tension from ∼80 to ∼32 N/m. Therefore, hydrated protons must have a unique water arrangement that enables them to propagate without sinking into bulk water. This local polarized hydrogen bond network in the interfacial water region is characterized by a translational spectrum similar to that of ice V.
Transparent electrodes with nanorings: A computational point of view
Authors: Azani Mohammad-Reza , Hassanpour Azin , Tarasevich Yuri Yu. , Vodolazskaya Irina V. , Eserkepov Andrei V.
Published: June 2019

Four samples of transparent conductive films with different numbers of silver nanorings per unit area were produced. The sheet resistance, transparency, and haze were measured for each sample. Using Monte Carlo simulation, we studied the electrical conductivity of random resistor networks produced by the random deposition of the conducting rings onto the substrate. Both systems of equal-sized rings and systems with rings of different sizes were simulated. Our simulations demonstrated the linear dependence of the electrical conductivity on the number of rings per unit area. Size dispersity decreased the percolation threshold, but without having any other significant effect on the behavior of the electrical conductance. Analytical estimations obtained for dense systems of equal-sized conductive rings were consistent with the simulations.
Strain engineered linear dichroism and Faraday rotation in few-layer phosphorene
Authors: Li L. L. , Peeters F. M.
Published: June 2019

We investigate theoretically the linear dichroism and the Faraday rotation of strained few-layer phosphorene, where strain is applied uniaxially along the armchair or zigzag direction of the phosphorene lattice. We calculate the optical conductivity tensor of uniaxially strained few-layer phosphorene by means of the Kubo formula within the tight-binding approach. We show that the linear dichroism and the Faraday rotation of few-layer phosphorene can be significantly modulated by the applied strain. The modulation depends strongly on both the magnitude and direction of strain and becomes more pronounced with increasing number of phosphorene layers. Our results are relevant for mechano-optoelectronic applications based on optical absorption and Hall effects in strained few-layer phosphorene.
Machine learning approach for analyzing complex data from atomic force microscopes
Authors: Liebendorfer Adam
Published: June 2019

Model-free and machine learning based technique generates and compares libraries of “force fingerprints” to probe specific questions with high volumes of atomic force microscopy data.
The evolution of FWI and its perceived benefits
Authors: Martin Tony , Long Andrew
Published: June 2019

Despite the mathematics behind full waveform inversion (FWI) being published in the early 1980s, it was 30 years before the method could be efficiently implemented on the scale of conventional 3D marine seismic volumes. FWI has evolved from using only transmitted waves and being constrained because towed streamer data lacked the very long offsets and ultra-low frequencies necessary to derive stable velocity updates beyond shallow depths. FWI now uses the full seismic wavefield (both transmitted and scattered wavefields), recovers deep velocity updates for standard offsets and frequencies and increasingly uses a wider range of frequencies that contribute to seismic imaging. We use several case examples to consider the benefits and caveats for robust FWI application: for resolving near-surface features and reducing seismic imaging uncertainty in areas with complex overburden heterogeneities; for resolving near-surface features and improving volumetric estimates; for using an enlarged bandwidth to resolve small model features; for updating the velocity in high contrast regimes; and for the creation of survey-wide, high-resolution models to reduce imaging uncertainty, complement attribute analysis, estimate elastic properties and prospect derisking. Collectively, we demonstrate how to produce high-resolution velocity models when conventional methods cannot and how to generate earth models in an accelerated fashion to reduce project turnaround. We describe pragmatic limits to what maximum FWI frequencies are reasonable and suggest ways that may soon by-pass signal processing and obtain direct earth attributes.
Impact of in-seam drilling performance on coal seam gas production and remaining gas distribution
Authors: Zhou Fengde , Fernandes Glen , Luft Joao , Ma Kai , Oraby Mahmoud , Guevara Mariano Ospina , Kuznetsov Dan , Pinder Brad , Keogh Sean
Published: June 2019

Drilling horizontal wells in low permeability coal seams is a key technology to increase the drainage area of a well, and hence, decrease costs. It’s unavoidable that some parts of the horizontal section will be drilled outside the targeted coal seam due to unforeseen subsurface conditions, such as sub-seismic faulting, seam rolls, basic geosteering tools, drilling practices and limited experiences. Therefore, understanding the impact of horizontal in-seam drilling performance on coal seam gas (CSG) production and remaining gas distribution is an important consideration in drilling and field development plans. This study presents a new workflow to investigate the impact of horizontal in-seam performance on CSG production and gas distribution for coal seams with different porosity, permeability, permeability anisotropy, initial gas content (GC), initial gas saturation and the ratio of in-coal length to in-seam length (RIIL). First, a box model with an area of 2 km × 0.3 km × 6 m was used for conceptual simulations. Reduction indexes of the cumulative gas production at the end of 10 years of simulations were compared. Then, a current Chevron well consisting of a vertical well and two lateral wells, was selected as a case study in which the impact of outside coal drilling on history matching and remaining gas distribution were analysed. Results show that the RIIL plays an increasing role for cases with decreasing permeability or initial gas saturation, while it plays a very similar role for cases with varied porosity, permeability anisotropy and GC. The size and location of outside coal drilling will affect the CSG production and remaining gas distribution.
Influence of elastoplastic embedment on CSG production enhancement using graded particle injection
Authors: You Zhenjiang , Wang Duo , Leonardi Christopher , Johnson Jr Raymond , Bedrikovetsky Pavel
Published: June 2019

A large percentage of coal seam gas (CSG) reservoirs exhibit low permeability and require stimulation to achieve economic production rates. Graded particle injection (GPI) into the natural fracture and cleat system around hydraulically-induced fractures has been proposed and demonstrated by prior laboratory studies as an effective method of enhancing CSG production. However, pore pressure and fracture width decrease with the distance from the wellbore and hydraulic fractures. Previous modelling determined that staging the injected particles with increasing size may sequentially fill the propped cleats and keep them open during production. GPI results in an increase in permeability above the initial value, expands the stimulated zone, and consequently, increases the productivity index.
The present work aims to improve our understanding of the GPI process for production enhancement by developing a generalised modelling methodology for GPI into the fracture network. The new model accounts for elastoplastic deformation of fracture surface during particle embedment. This is based on elastoplastic finite element modelling of fracture deformation and flow modelling by the lattice Boltzmann method (LBM). Effects of packing densities, effective stress and material properties are incorporated in the modelling. Results of fracture permeability reduction factor due to particle embedment are then applied to the mathematical model for well productivity prediction. Modelling results indicate that elastoplastic fracture deformation leads to lower permeability and production enhancement using GPI, as compared with linear elastic deformation applied in traditional models.
The developed model is applicable to the assessment of potential stimulation outcomes for a range of uncertain reservoir parameters. Better understanding and implementation of GPI schemes can potentially improve post-fracturing results in low-permeability coal intervals substantially.
Engineering and environmental studies for decommissioning of subsea infrastructure
Authors: Raitt Petrina , Selman Allison , Lanoëlle Céline
Published: June 2019

Decommissioning of subsea infrastructure requires input from engineering and environmental studies, as well as the stakeholders, so that informed decisions can be made. This paper discusses the technical and environmental considerations relating to the decommissioning of subsea infrastructure for the full range of subsea components, including structures, rigid pipelines, flexible flowlines and control systems. Example engineering and environmental assessments that could be performed are discussed, such as stability, corrosion, lifting, materials degradation, net environmental benefit assessment (NEBA) and marine and fishing studies. The stakeholder engagement process is also presented. The paper discusses processes leading up to the decommissioning decision and what operators can do, to ensure that there is adequate information to support decisions that need to be made on transitioning into the final stage of the asset lifecycle. The paper will provide guidance on execution of the decommissioning works, how to ensure success and considerations for material handling, management and disposal of potentially hazardous and contaminated material and other environmental impacts. The technical aspects will be presented using case studies on past and present decommissioning projects in Australia. Solutions for in situ, recovery and repurposing that have been adopted will be presented, as well as alternative solutions that are currently being developed.
Real-time drilling optimisation – driving drilling excellence
Authors: Barhate Abhijit , Patel Piyush , Abrahamsen Egil
Published: June 2019

Here we explore a real-time solution that anticipates drilling events and avoid delays caused by such issues as poor hole cleaning, higher torque and drag, swab and surge, stuck pipe, lost circulation, formation damage and wellbore instability. This is important if drilling optimisation is a major technical and corporate goal or if you wish to go beyond the traditional approach of collecting real-time data only to monitor operations. The presented state-of-the-art ‘real-time drilling optimisation’ solution creates a dynamic, real-time picture of the entire wellbore and key drilling variables and parameters using advanced, tightly coupled thermodynamic, hydraulic and mechanical drilling models and trend analysis applications to anticipate potential drilling issues in real-time while drilling. The solution can also be used to perform scenario based ‘what-if’ analysis and ‘look-ahead’ simulations of drilling operation with the purpose to analyse outcome of alternative operating scenarios. This is an effective solution that simplifies real-time data analysis by using trends and deviations between modelled and actual data to predict changing wellbore conditions and developing a digital twin of a wellbore. This paper includes robotic drilling automation, aimed at reducing invisible loss time, enhancing drilling efficiency and safety by applying operational safeguards to the drilling control system, providing automatic safety mechanisms and enabling automatic sequences. This paper highlights technical cases demonstrating how this analytic solution not only auto-detects symptoms (which can lead to drilling events or hazards, invisible loss time and non-productive time) but also optimises drilling performance through simulation well ahead of time, thus driving drilling efficiency.
Rock properties and in-situ stress state of the Egilabria Prospect, Lawn Hill Platform, Queensland
Authors: Bailey Adam H. E. , Wang Liuqi , Hall Lisa , Henson Paul
Published: June 2019

The Energy component of Geoscience Australia’s Exploring for the Future (EFTF) program is aimed at improving our understanding of the petroleum resource potential of northern Australia, in partnership with the state and territory geological surveys. The sediments of the Mesoproterozoic South Nicholson Basin and the underlying Paleoproterozoic Isa Superbasin in the Northern Territory and Queensland are amongst the primary targets of the EFTF Energy program, as they are known to contain organic-rich sedimentary units with the potential to host unconventional gas plays, although their subsurface extent under the cover of the Georgina Basin is presently unknown. In order to economically produce from unconventional reservoirs, the petrophysical rock properties and in-situ stresses must be conducive to the creation of secondary permeability networks that connect a wellbore to as large a reservoir volume as possible. This study utilises data from the recently drilled Armour Energy wells Egilabria 2, Egilabria 2-DW1, and Egilabria 4 to constrain rock properties and in-situ stresses for the Isa Superbasin sequence where intersected on the Lawn Hill Platform of north-west Queensland. These results have implications for petroleum prospectivity in an area with proven gas potential, which are discussed here in the context of the rock properties and in-situ stresses desired for a viable shale gas play. In addition, these results are relevant to potential future exploration across the broader Isa Superbasin sequence.
Structural Systematics of Lanthanide(III) Picrate Solvates: Neutral, Mononuclear Ln(pic)3(dimethylsulfoxide)3 Arrays
Authors: Asfari Zouhair , Chan Eric J. , Harrowfield Jack M. , Skelton Brian W. , Sobolev Alexandre N. , Thuéry Pierre , White Allan H.
Published: June 2019

Adducts of dimethylsulfoxide, dmso=Me2SO, with lanthanide(iii) picrates (picrate=2,4,6-trinitrophenoxide, pic) of stoichiometry Ln(pic)3·3dmso have been prepared and characterised by single-crystal X-ray structure determinations as discrete, neutral, mononuclear molecular species. Such complexes have been obtained across the gamut of Ln, specifically for Ln=La, Pr, Nd, Sm, Gd, Dy, Yb, Lu, and Y, presumably also accessible for other intermediate members, the series being isomorphous (monoclinic, C2/c, Z=8); a second triclinic P form has also been identified for Ln=La, Pr. In both forms, the metal atom coordination environments are nine-coordinate, tricapped trigonal prismatic, [Ln(dmso-O)3(pic-O,O′)3], two of the three unidentate ligands lying in one of the trigonal planes and one in the other (an isomer we have termed meridional, mer). A hydrated form of Ln(pic)3·2dmso·H2O stoichiometry has also been defined for Ln=Sm, Gd, Lu, the metal atom environment again nine-coordinate, [Ln(dmso-O)2(H2O)(pic-O,O′)3], but now fac, with the three unidentate ligands occupying one triangular face of the tricapped trigonal prism and involved in a centrosymmetric H-bonding array with the three similar ligands of an adjacent complex; the three capping atoms are nitro-oxygen atoms, the phenoxy-O triad occupying the other face.
Establishing the nurse practitioner workforce in rural New Zealand: barriers and facilitators
Authors: Adams Sue , Carryer Jenny
Published: June 2019

ABSTRACT
INTRODUCTIONThe health sector is facing considerable challenges to meet the health needs of rural communities. Nurse practitioners (NPs) deliver primary health care (PHC) services similar to general practitioner (GP) services, within a health equity and social justice paradigm. Despite GP workforce deficits, New Zealand has been slow to effectively utilise NPs.
AIMFrom a larger study exploring the establishment of NP services, this paper reports on the barriers and facilitators to becoming a NP in rural PHC.
METHODSOverall, 13 NPs and 4 NP candidates participated in individual or group interviews. Participants were employed in a variety of PHC settings from six district health boards across New Zealand. Using a scaffold map constructed to show the stages of the pathway from nurse to NP, data were analysed to identify experiences and events that facilitated or were barriers to progress.
RESULTSExperiences varied considerably between participants. Commitment to the development of the NP role in their local areas, including support, advanced clinical opportunities, supervision, funding and NP job opportunities, were critical to progression and success. Existing GP shortages and the desire to improve health outcomes for communities drove nurses to become NPs.
DISCUSSIONImplementation of the NP workforce across New Zealand remains ad hoc and inconsistent. While there are pockets of great progress, overall, the health sector has failed to embrace the contribution that NPs can make to PHC service delivery. A national approach is required to develop the NP workforce as a mainstream PHC provider.
Effectiveness of chronic obstructive pulmonary disease self-management interventions in primary care settings: a systematic review
Authors: Hosseinzadeh Hassan , Shnaigat Mahmmoud
Published: June 2019

Chronic obstructive pulmonary disease (COPD) is one of the more disabling diseases and the third cause of mortality worldwide. Self-management is considered an effective strategy for controlling and managing COPD. This review aims to summarise the available evidence on the effectiveness of COPD self-management in primary care settings. Social Sciences, Citation Index, MEDLINE, CINAHL, Academic Search Complete and Scopus were searched for randomised controlled trials of COPD self-management in general practice between 2001 and 2018. Ten randomised controlled trials of COPD self-management trials conducted in primary care settings were included in this review. The identified trials have recruited stable patients; a majority having mild to moderate COPD. The trials implemented different types of interventions and measured improvements in knowledge, skills and behaviours of self-management, mental health, self-efficacy and endpoint outcomes such as hospitalisation and quality of life. The findings showed that COPD self-management trials had positive effects on COPD knowledge and improved self-management behaviours such as adherence to medication, physical activities and smoking cessation in some cases; however, the effect of trials on hospitalisation rate, quality of life and healthcare utilisation were not conclusive. There was also not enough evidence to suggest that the trials were efficient in improving self-efficacy, a major driver of self-management behaviours. Primary care COPD self-management trials are efficient in improving surrogate outcomes such as knowledge of and adherence to self-management behaviours; however, such improvements are less likely to be sustainable in the absence of self-efficacy. Future studies should also focus on improving endpoint self-management outcomes like hospitalisation rate and quality of life to benefit both patient and healthcare system.