bluuebunny/crossref_metadata_2025 huggingface dataset:
Prussian blue-assisted one-pot synthesis of nitrogen-doped mesoporous graphitic carbon spheres for supercapacitors
Authors: Dassanayake Arosha C. , Wickramaratne Nilantha P. , Hossain Mohammad Akter , Perera Vindya S. , Jeskey Jacob , Huang Songping D. , Shen Hao , Jaroniec Mietek
Published: September 2019

One-pot synthesis of nitrogen doped mesoporous graphitic carbon spheres with dispersed metal oxide nanoparticles using a single temperature treatment step serves as one of the big challenges in materials research.
Reversible immobilization of a protein to a gold surface through multiple host–guest interactions
Authors: Schwarz Dennis H. , Elgaher Walid A. M. , Hollemeyer Klaus , Hirsch Anna K. H. , Wenz Gerhard
Published: September 2019

Monolayers were formed by specific interactions between adamantylated proteins (transferrin, lysozyme) and a β-cyclodextrin (β-CD) monolayer on a gold surface.
Predicted polymorph manipulation in an exotic double perovskite oxide
Authors: Su He-Ping , Li Shu-Fang , Han Yifeng , Wu Mei-Xia , Gui Churen , Chang Yanfen , Croft Mark , Ehrlich Steven , Khalid Syed , Adem Umut , Dong Shuai , Sun Young , Huang Feng , Li Man-Rong
Published: September 2019

First-principles density functional theory calculations, for the first time, was used to predict the Mg3TeO6-to-perovskite type phase transition in Mn3TeO6at around 5 GPa.
Molecular origin of efficient hole transfer from non-fullerene acceptors: insights from first-principles calculations
Authors: Benatto Leandro , Marchiori Cleber F. N. , Araujo C. Moyses , Koehler Marlus
Published: September 2019

Our results suggest the conditions to promote an efficient hole transfer from acceptors induced by molecular orbital delocalization.
Low power density 980 nm-driven ultrabright red-emitting upconversion nanoparticles via synergetic Yb3+/Tm3+ cascade-sensitization
Authors: Liu Jiao , Wu Shihong , Chu Huiyuan , Wang Chaozhan , Shen Ji-Wei , Wei Yinmao , Wu Peng
Published: September 2019

Herein, we report the first example of synergetic Yb3+ → Tm3+ → Er3+ cascade-sensitized ultrabright red-emitting upconversion nanoparticles with high quantum yield under low power density excitation at 980 nm.
ALMA captures feeding and feedback from the active galactic nucleus in NGC 613
Authors: Audibert A. , Combes F. , García-Burillo S. , Hunt L. , Eckart A. , Aalto S. , Casasola V. , Boone F. , Krips M. , Viti S. , Muller S. , Dasyra K. , van der Werf P. , Martín S.
Published: September 2019

We report ALMA observations of CO(3–2) emission in the Seyfert/nuclear starburst galaxy NGC 613, at a spatial resolution of 17 pc, as part of our NUclei of GAlaxies (NUGA) sample. Our aim is to investigate the morphology and dynamics of the gas inside the central kiloparsec, and to probe nuclear fueling and feedback phenomena. The morphology of CO(3–2) line emission reveals a two-arm trailing nuclear spiral at r ≲ 100 pc and a circumnuclear ring at a radius of ∼350 pc that is coincident with the star-forming ring seen in the optical images. Also, we find evidence for a filamentary structure connecting the ring and the nuclear spiral. The ring reveals two breaks into two winding spiral arms corresponding to the dust lanes in the optical images. The molecular gas in the galaxy disk is in a remarkably regular rotation, however the kinematics in the nuclear region are very skewed. The nuclear spectrum of CO and dense gas tracers HCN(4–3), HCO+(4–3), and CS(7–6) show broad wings up to ±300 km s−1, associated with a molecular outflow emanating from the nucleus (r ∼ 25 pc). We derive a molecular outflow mass Mout = 2 × 106 M⊙ and a mass outflow rate of Ṁout = 27 M⊙ yr−1. The molecular outflow energetics exceed the values predicted by AGN feedback models: the kinetic power of the outflow corresponds to PK, out = 20%LAGN and the momentum rate is Ṁoutv ∼ 400LAGN/c. The outflow is mainly boosted by the AGN through entrainment by the radio jet, but given the weak nuclear activity of NGC 613, we might be witnessing a fossil outflow resulting from a previously strong AGN that has now faded. Furthermore, the nuclear trailing spiral observed in CO emission is inside the inner Lindblad resonance ring of the bar. We compute the gravitational torques exerted in the gas to estimate the efficiency of the angular momentum exchange. The gravity torques are negative from 25 to 100 pc and the gas loses its angular momentum in a rotation period, providing evidence for a highly efficient inflow towards the center. This phenomenon shows that the massive central black hole has significant dynamical influence on the gas, triggering the inflowing of molecular gas to feed the black hole.
Structure and kinematics of the Taurus star-forming region from Gaia-DR2 and VLBI astrometry
Authors: Galli P. A. B. , Loinard L. , Bouy H. , Sarro L. M. , Ortiz-León G. N. , Dzib S. A. , Olivares J. , Heyer M. , Hernandez J. , Román-Zúñiga C. , Kounkel M. , Covey K.
Published: September 2019

Aims. We take advantage of the second data release of the Gaia space mission and the state-of-the-art astrometry delivered from very long baseline interferometry observations to revisit the structure and kinematics of the nearby Taurus star-forming region.

Methods. We apply a hierarchical clustering algorithm for partitioning the stars in our sample into groups (i.e., clusters) that are associated with the various molecular clouds of the complex, and derive the distance and spatial velocity of individual stars and their corresponding molecular clouds.

Results. We show that the molecular clouds are located at different distances and confirm the existence of important depth effects in this region reported in previous studies. For example, we find that the L 1495 molecular cloud is located at d = 129.9+0.4−0.3 pc, while the filamentary structure connected to it (in the plane of the sky) is at d = 160.0+1.2−1.2 pc. We report B 215 and L 1558 as the closest (d = 128.5+1.6−1.6 pc) and most remote (d = 198.1+2.5−2.5 pc) substructures of the complex, respectively. The median inter-cloud distance is 25 pc and the relative motion of the subgroups is on the order of a few km s−1. We find no clear evidence for expansion (or contraction) of the Taurus complex, but signs of the potential effects of a global rotation. Finally, we compare the radial velocity of the stars with the velocity of the underlying 13CO molecular gas and report a mean difference of 0.04 ± 0.12 km s−1 (with rms of 0.63 km s−1) confirming that the stars and the gas are tightly coupled.
Stellar systems following the R1/m luminosity law
Authors: Baes Maarten , Ciotti Luca
Published: September 2019

We expand our previous analytical and numerical studies of the family of Sérsic models, which are routinely used to describe early-type galaxies and the bulges of spiral galaxies. In particular, we focus on the total energy budget, an important dynamical property that has not been discussed in detail in previous works. We use two different methods to calculate the total energy for the Sérsic model family that result in two independent expressions that can be used along the entire sequence of Sérsic models. We use these expressions to investigate whether the Spitzer concentration index is a reliable measure for the intrinsic 3D concentration of galaxies, and we conclude that it is not a very useful measure for the central concentration. The popular Third Galaxy Concentration index, on the other hand, is shown to be a reliable measure for the intrinsic 3D concentration, even though it is based on the surface brightness distribution and not on the intrinsic 3D density.
Ultraschnell wirksame Betablocker Esmolol und Landiolol: Aktuelle Rolle in der Intensiv- und Notfallmedizin
Authors: Gassanov Natig , Er Fikret
Published: September 2019

Die schnell und kurzwirksamen Betablocker Esmolol und Landiolol sind zugelassen zur Therapie der supraventrikulären Tachykardien. Beide Substanzen sind kardioselektiv mit einer sehr hohen β1-Rezeptor-Selektivität.

Esmolol und Landiolol können aufgrund ihrer pharmakologischen Eigenschaften eine Alternative zu anderen Substanzen in der Notfall- und Intensivmedizin sein. Die meisten klinischen Studien deuten auf einen günstigen Effekt der ultrakurz wirksamen Betablocker auf die Herzfrequenz und andere hämodynamische Parameter hin. Jedoch fehlen bisher die qualitativ hochwertigen Studien, die eine eindeutige Überlegenheit der beiden β-Adrenorezeptor-Antagonisten gegenüber den etablierten Wirkstoffen zeigen. Angesichts der aktuellen Datenlage bleibt der Einsatz der beiden Betablocker ausgewählten Patienten mit Tachyarrhythmien vorbehalten, die unzureichend auf die bisherige Therapie ansprechen.
Musculoskeletal Rehabilitation after Hip Fracture: A
Review
Authors: Pfeifer Michael , Dionyssiotis Yannis
Published: September 2019

With increasing longevity, hip fractures become more and more a serious burden
not only for societies in developed civilization, but also for emerging
countries. According to world-wide projections 1.5 million people are affected
each year. Although a lot of research has been performed over the last decade,
there is still a lack of standardized and evidence-based approaches for
prevention, treatment, and rehabilitation of this worst complication of
osteoporosis.

Therefore, the evidence base for this article was synthesized in accordance with
SIGN methodology. Databases searched include Medline, Embase, Cinahl and the
Cochrane Library between March 1999 and March 2019. The following terms are
used: osteoporosis, hip fracture, rehabilitation, falls, muscle strength,
nutrition, exercise, balance, sway, and hip protectors. Moreover, reference
lists from included studies were checked and author`s names were searched for
additional studies.

Possibly, the best approach to rehabilitation after hip fracture is a
multi-disciplinary team co-ordinating medical, social, educational and
vocational measure for training or retraining the individual to the highest
possible level of function. In order to prevent thromboembolism low-dose
anti-coagulation therapy (e. g. fondaparinux, rivaroxaban) may be used for
approximately two weeks after surgery. This should be accompanied by a daily
nutritional intake of at least 20 g protein, 1200 mg of elemental calcium and
800 I. U. of vitamin D, whereas in severe vitamin D insufficiencies
recommendations may be certainly higher.

After surgical repair of the hip fracture, an anti-resorptive medication may be
started. While balance training and performing of Tai Chi has been shown to
reduce fall risk and thereby also decrease hip fracture risk, the use of hip
protectors is still under evaluation and cannot be generally advocated.
Early Detection of Diseases by Radiological Imaging: New Legal Situation and Evaluation of Service Offers using CT Examinations as an Example
Authors: Brix Gunnar , Nekolla Elke Anna , Griebel Jürgen
Published: September 2019

Background Radiological imaging offers promising prospects for the early detection of diseases. In Germany, the legal framework for such examinations was created by the Radiation Protection Law, which entered into force on December 31, 2018. Under this law, each specific type of radiodiagnostic screening of non-communicable diseases needs an approval on a generic level (permission) by a federal statutory ordinance, defining the specific requirements and conditions. It is the aim of the present paper, (i) to present in detail the new legal situation and (ii) to assess actual service offers for the screening of asymptomatic persons using CT examinations as an example.

Method In February 2019, radiology institutions in Germany illegally offering on the Internet CT examinations for the screening of lung and colon cancer or coronary artery disease were identified. For each type of examination, 50 pertinent websites were evaluated particularly regarding the general information on the offered screening examination and the concrete procedure.

Results In the vast majority of cases, the information provided on the websites was inadequate and disproportionately emphasized the benefits over the risks of the screening examination. Moreover, the offers differed substantially with respect to the age and risks factors of potential participants, the frequency of examinations, the screening procedure, and the diagnostic workup.

Conclusion The evaluated service offers strongly substantiate the need to define requirements and conditions regarding radiological screening examinations by statutory ordinances, in order to ensure an informed decision of potential screening participants as well as the benefit versus the risks of the procedures.

Key Points: 

Citation Format
The International Prospective Glanzmann Thrombasthenia Registry: Pediatric Treatment and Outcomes
Authors: Zotz Rainer B. , Poon Man-Chiu , Di Minno Giovanni , D'Oiron Roseline ,   for the Glanzmann Thrombasthenia Registry Investigators
Published: September 2019

Background Standard treatment for Glanzmann thrombasthenia (GT), a severe inherited bleeding disorder, is platelet transfusion. Recombinant activated factor VII (rFVIIa) is reported to be effective in GT with platelet antibodies and/or refractoriness to platelet transfusions.

Methods We evaluated rFVIIa effectiveness and safety for the treatment and prevention of surgical and nonsurgical bleeding in children <18 years old, with or without platelet antibodies and/or refractoriness, as reported in the GT Registry (GTR). Data were used from the GTR, an international, multicenter, observational, postmarketing study of rFVIIa that prospectively collected data on the treatment and outcomes of bleeds in patients with GT. Only patients with a diagnosis of congenital GT were included in the registry.

Results Between 2007 and 2011, 27 children were treated for 44 surgical procedures (minor: 36; major: 8); nonsurgical bleeds occurred in 104 patients (599 episodes: severe, 145; moderate, 454; spontaneous, 423; posttraumatic, 176). The effectiveness of treatment for minor procedures, major procedures, nonsurgical bleeds was 6/6, 1/1, and 75/84 for rFVIIa, 6/6, 2/2, and 64/76 for rFVIIa + antifibrinolytics (AF), 11/12, 1/1, and 162/214 for platelets ± AF, and 5/6, 0/3, and 33/45 for rFVIIa + platelets ± AF. In all, 25 adverse events were reported in children; no thromboembolic events were reported.

Conclusion For all patients, regardless of platelet antibody or refractoriness status, rFVIIa, administered with or without platelets (± AF), provided effective hemostasis with a low frequency of adverse events in surgical, as well as nonsurgical, bleeding in patients with GT.

clinicaltrials.gov identifier: NCT01476423.
Adenocarcinoma of the Sinonasal Tract: A Review of the National Cancer Database
Authors: Patel Neil N. , Maina Ivy W. , Kuan Edward C. , Triantafillou Vasiliki , Trope Michal A. , Carey Ryan M. , Workman Alan D. , Tong Charles C. , Kohanski Michael A. , Palmer James N. , Adappa Nithin D. , Newman Jason G. , Brant Jason A.
Published: September 2019

Background Sinonasal adenocarcinoma (SNAC) is a rare malignancy arising from mucus-secreting glandular tissue. Limited large-scale studies are available due to its rarity. We evaluated SNAC in the National Cancer Database (NCDB), a source that affords multi-institutional, population studies of rare cancers and their outcomes.

Methods The NCDB was queried for adenocarcinoma in the sinonasal tract. Multivariate analyses were performed to evaluate for factors contributing to overall survival (OS).

Results A total of 553 patients were identified. The cohort was composed of 59.3% males. The nasal cavity was the most common primary site, representing 44.1% of cases. About 5.7% of patients presented with nodal disease, while 3.3% had distant metastases. About 40.6% of cases presented with stage IV disease. About 73.5% of patients underwent surgery, 54.2% received radiation therapy, and 27.7% had chemotherapy. Median OS was 71.7 months, while OS at 1, 2, and 5 years was 82, 73.0, and 52%, respectively. On multivariate analysis, advanced age (hazard ratio [HR]: 1.04; 95% confidence interval [CI]: 1.02–1.05), Charlson–Deyo score of 1 (HR: 1.99; 95% CI: 1.20–3.30), advanced tumor grade (HR: 2.73; 95% CI: 1.39–5.34), and advanced tumor stage (HR: 2.71; 95% CI: 1.33–5.50) were associated with worse OS, whereas surgery (HR: 0.34; 95% CI: 0.20–0.60) and radiation therapy (HR: 0.55; 95% CI: 0.33–0.91), but not chemotherapy (HR: 1.16; 95% CI: 0.66–2.05), predicted improved OS.

Conclusions SNAC is a rare malignancy with 5-year survival approximating 50%. Surgery and radiation therapy, but not chemotherapy, are associated with improved survival, and likely play a critical role in the interdisciplinary management of SNAC.
Renal–Hepatic–Pancreatic Dysplasia: An Ultra-Rare Ciliopathy with a Novel NPHP3 Genotype
Authors: Cagan Appak Yeliz , Baran Masallah , Ozturk Hismi Burcu , Ozyilmaz Berk , Vardi Kader , Ozer Kaya Ozge , Aksoy Betul , Kasap Demir Belde
Published: September 2019

Renal–hepatic–pancreatic dysplasia-1 (RHPD1) is an ultra-rare genetic disorder with a high mortality. It is caused by biallelic pathogenic variants in NPHP3, which encode nephrocytin, an important component of the ciliary protein complex. The NPHP3-related disease phenotype is diverse with RHPD1, nephronophthisis-3, and Meckel syndrome-7. In this case report, we present a female infant with hepatomegaly, cholestasis, and elevated transaminases who was found to carry a homozygous c.2975C > T variant of NPHP3. This is the first description of this genotype and RHPD1 phenotype in the literature. The patient is currently being closely monitored for the necessity of combined renal and liver transplantation under supportive treatment.
Surgical Mesoportal Bypass and Portosystemic Shunt Interventions
Authors: Jeyakumar Arthie , Chick Jeffrey Forris Beecham , Healey Patrick J. , Monroe Eric J.
Published: September 2019

Extrahepatic portal vein obstruction is defined by obstruction of the extrahepatic portal vein with or without involvement of the intrahepatic veins and does not include isolated thrombosis of the splenic vein or superior mesenteric vein. The etiology may be congenital versus acquired and acute versus chronic. Historically, surgical intervention has been reserved for patients with symptoms refractory to medical or endoscopic management. Over time, however, advances in surgical technique and research have caused a shift in practice. The interventionalists' role is primarily to address clinically significant shunt dysfunction, including shunt stenosis and thrombosis. In this article, the authors discuss the classification and indications of surgical portosystemic conduits, pre-and postoperative imaging, and clinical signs, and endovascular techniques to address shunt dysfunction.
Ferroelectric phase transition and crystal asymmetry monitoring of SrTiO3 using quasi TE
m,1,1 and quasi TM
m,1,1 modes
Authors: Hosain M. A. , Le Floch J.-M. , Bourhill J. F. , Krupka J. , Tobar M. E.
Published: September 2019

Dielectric spectroscopy of a SrTiO3 single crystal over a broad range of microwave frequency using quasi TEm,1,1 and quasi TMm,1,1 modes reveals crystal asymmetry from typical measurement of Q-factor, transmission, or frequency characteristics in continuous cooling down to a few Kelvin. The properties of the modes due to the crystal asymmetry are validated by implementing a quasiharmonic phonon approximation. The observed ferroelectric phase transition temperature is around 51 K, and quantum-mechanical stabilization of the paraelectric phase arises below 5 K with very high permittivity. Also, an antiferrodistortive transition was indicated at 105 K. Landau’s theory of correlation length supports the observation of an extra-loss term so the transition may be identified near the Q-factor maxima or transmission maxima depending on the other loss terms present in the cavity. Thus, the ferroelectric phase transition with respect to temperature is identified when its extra-loss term causes a discontinuity or deviation in the derivative of the temperature characteristic near the minimum of total cavity loss (maximum Q-factor or maximum transmission temperature characteristic). This temperature is confirmed by transmission amplitude variation of quasi TE2,1,1 under 200 V dc electric field showing the existence of the soft-mode. These measurements support a typical polarization model and explicit temperature dependency of the soft-mode incorporating an imaginary frequency.
Generation and stability of structurally imprinted target skyrmions in magnetic multilayers
Authors: Kent Noah , Streubel Robert , Lambert Charles-Henri , Ceballos Alejandro , Je Soong-Gun , Dhuey Scott , Im Mi-Young , Büttner Felix , Hellman Frances , Salahuddin Sayeef , Fischer Peter
Published: September 2019

Target Skyrmions (TSks) are extended topological spin textures with a constant chirality where the rotation of the z component of the magnetization is larger than π. TSks have topological charge 1 or 0, if the z component of the magnetization Mz goes through a rotation of nπ where n is an odd or even integer, respectively. TSks with a rotation of the z component of up to 4π have been imaged via high spatial resolution element-specific x-ray imaging. The TSks were generated by weakly coupling 30 nm thin Permalloy (Ni80Fe20, PY) disks with a 1 μm diameter to asymmetric (Ir 1 nm/Co 1.5 nm/Pt 1 nm) × 7 multilayers that exhibit Dzyaloshinskii-Moriya interaction. The PY disks stabilize the TSks in the multilayers due to reduced stray field energy and enforced circular symmetry from pinning of domain walls at the edges of the disks. Upon applying external magnetic fields, it is the skyrmion core at the center that ensures stability of the TSk, whereas the collapse of the extended structures in the TSk does not depend on the topological charge.
A single-lens universal interferometer: Towards a class of frugal optical devices
Authors: Munjal Pooja , Singh Kamal P.
Published: September 2019

The application of precision interferometers is generally restricted to expensive and smooth high-quality surfaces. Here, we offer a route to ultimate miniaturization of interferometers by integrating a beam splitter, reference mirror, and light collector into a single optical element, an interference lens (iLens), which produces stable high-contrast fringes from the in situ surface of paper, wood, plastic, rubber, unpolished metal, human skin, etc. A self-referencing real-time precision of a sub-20 picometer (∼λ/30 000) is demonstrated with simple intensity detection under ambient conditions. The principle of iLens interferometry has been exploited to build a variety of compact devices, such as a paper-based optical picobalance, having 1000 times higher sensitivity and speed, when compared with a high-end seven-digit electronic balance. Furthermore, we used cloth, paper, and polymer films to readily construct broadband acoustic sensors possessing matched or higher sensitivity when compared with piezo and electromagnetic sensors. Our work opens the path for affordable yet ultraprecise frugal photonic devices and universal microinterferometers for imaging.
A sub-microsecond-range pulse generator based on anti-resonance network and transmission line transformer
Authors: Cheng Xinbing , Hu Yongjun , Chen Rong , Yang Jianhua , Pan Zilong
Published: September 2019

A sub-microsecond-range pulse generator based on an antiresonance network and transmission line transformer (TLT) is presented in this paper. The three-section antiresonance network (TSAN) and three-stage TLT take the roles of the pulse forming module and pulse voltage boosting module of this generator, respectively. The TSAN is applied to obtain a high quality and fixed flat top quasisquare pulse with fewer sections, and the three-stage TLT is used to obtain a higher voltage gain. Experimental results show that if the charging voltage of the TSAN is about 15.0 kV, the amplitude and pulse duration of the output voltage of the TSAN are about 7.2 kV and 400 ns, respectively, which correspond to the theoretical calculation results. Meanwhile, the amplitude of the output voltage of TLT is about 22.0 kV, so the voltage step-up ratio of the three-stage TLT is about 3.05. This generator displayed in the publication can transmit voltage pulses with low loss.
Design and construction of a novel instrument for high-frequency micro-force electrical sliding friction testing
Authors: Chen Hai-chao , Cao Zhong-qing , Chen Guang-yan , Wang Bei , Gong Cong-yu , Zhang Zhi-xing , Cai Zhen-bing
Published: September 2019

Sliding electrical contact exists in various electrical equipment. However, its performance is significantly affected by the sliding condition such as the load, electricity, and the surface state of friction pairs. In this study, a novel instrument is designed and constructed for high-frequency microforce electrical sliding friction testing. The new instrument provides a unique experimental platform that enables high-frequency reciprocating friction and microforce loading, and it has an innovative data collection system that includes a cantilever beam structure to measure the microforce. In this instrument, parameters (positive force, friction, displacement, and voltage of frictional pair) are obtained and monitored in real time. The steel sheet and nickel-plated steel wire were used as materials to conduct an experiment, and the steel sheet morphology after the experiment was observed using a light microscope. Results show that the voltage and positive load significantly influence the friction coefficient and friction wear, which is crucial in understanding friction and wear behaviors.
Hydration of monovalent and divalent cations near a cathode surface
Authors: Kiyohara Kenji , Kawai Yusuke
Published: September 2019

Hydration of monovalent (Li+, Na+, K+, and Cs+) and divalent (Mg2+, Ca2+, Sr2+, and Ba2+) cations on a cathode surface was studied by a classical molecular dynamics simulation. The potential of mean force (PMF) for each cation species was calculated as a function of the distance from the cathode surface, and the potential barriers for dehydrating the first and second hydration shells near the cathode surface were estimated. The positions of the minimum of the PMF closest to the cathode surface were found to be in the order Li+ < Na+ < Mg2+ < Ca2+ < Sr2+ < Ba2+ < K+ < Cs+. It was found that Li+, Mg2+, Ca2+, Sr2+, and Ba2+ ions are most likely doubly hydrated when they are adsorbed on the cathode surface without an applied voltage, whereas Na+, K+, and Cs+ ions are most likely singly hydrated at room temperature. On the other hand, when a voltage of 1 V was applied to the electrodes, all the cation species that we studied appeared most likely to be singly hydrated on the cathode surface. The depths of the potential well closest to the cathode surface under an applied voltage of 1 V were found to be in the order Ba2+ < Sr2+ < Ca2+ < Mg2+ for the divalent cations and Li+ < Na+ < K+ < Cs+ for the monovalent cations in the set of models that we used. These orders coincide with the Hofmeister series from the kosmotropic to the chaotropic.
Density functional theory calculations of generalized stacking fault energy surfaces for eight face-centered cubic transition metals
Authors: Su Yanqing , Xu Shuozhi , Beyerlein Irene J.
Published: September 2019

In this work, we use density functional theory to calculate the entire generalized stacking fault energy (GSFE) surface for eight transition metals with a face-centered cubic structure: Ag, Au, Cu, Ir, Ni, Pd, Pt, and Rh. Analysis of the ⟨112⟩ GSFE curves finds that the displacements corresponding to the unstable stacking fault energy are larger than the ideal value for all eight metals except Ag and Cu. Over the entire surface, Pt is found to not possess well-defined local maxima or minima, suggesting spreading in favor of dissociation of the dislocation core, unlike the other seven metals. Our calculations also reveal that at a large ⟨112⟩ displacement, where atoms on two {111} adjacent planes are aligned, an anomalous local minimum occurs for Ir and Rh. The oddity is explained by relatively large, localized atomic displacements that take place in the two metals to accommodate the alignment that do not occur in the other six metals. In addition to the fully calculated surfaces, we characterize a continuous 11-term Fourier-series function, which provides a particularly excellent representation of the GSFE surfaces for Ag, Au, Cu, Ni, and Pd.
Cost-effective and durable Ru-sputtered Pt/C-based membrane–electrode assembly for passive direct methanol fuel cells
Authors: Jeong Wonyeop , Chang Ikwhang , Ryu Sangbong , Zheng Chunhua , Cha Suk Won , Park Taehyun
Published: September 2019

The present study demonstrates and evaluates the catalytic durability of ruthenium (Ru)-sputtered Pt/C-based membrane–electrode assembly (MEA) for passive direct methanol fuel cells (DMFCs). Sputtering of Ru onto the Pt/C catalyst layer on the electrolyte membrane reduces the use of Ru by more than 80% compared with conventional Pt-Ru/C (50:50 wt.%)-based MEAs. The Ru-sputtered MEA exhibited a high catalytic durability even when a high concentration of methanol (4 M) was used as fuel. In addition to the marked improvement in the catalytic durability, an increased performance was observed with passive DMFCs using Ru-sputtered MEAs. The results of the present study suggest that the new MEA fabrication method based on Ru-sputtered Pt/C considerably enhanced both the performance and durability of the cell while reducing the cost involved in fabrication. Furthermore, this study suggests ways to expand conventional MEAs for hydrogen fuel cells to the level of DMFCs.
Curriculum in conflict: how African American and Indigenous educational thought complicates the hidden curriculum
Authors: Pratt Alexander B.
Published: September 2019

This article is a discussion of the hidden curriculum and the settler‐colonial erasure that it propagates. There are two guiding questions that focus this work: (1) what are the assumptions that underlie the concept of the hidden curriculum and what do those assumptions obscure or erase; and (2) having raised the first question, is there a way forward for hidden curriculum analysis that can address the still valid concerns about tacit ideological messages in public schools without repeating the original constituting displacement of the hidden curriculum? I will employ a comparative analysis of select literature most commonly associated with the concept of the hidden curriculum and writings on education by Feminist, Black and Indigenous leaders and thinkers that speak to its ideas in a way that broadens and complicates its construction. I conclude this article with a discussion of the potential implications of these altered understandings for teacher and researcher practice.
Modeling GIRK channel conductance
Authors: Short Ben
Published: September 2019

JGP study uses MD simulations to investigate the gating and conductance of the inwardly rectifying potassium channel GIRK2.
Application of STED imaging for chromatin studies
Authors: Kostiuk Georgij , Bucevičius Jonas , Gerasimaitė Rūta , Lukinavičius Gražvydas
Published: September 2019

Chromatin is the information center of a cell. It comprises proteins and nucleic acids that form a highly complex and dynamic structure within the nucleus. Its multiple organization levels span from micrometre to nanometre scale. For many years, the lower levels of chromatin organization have been beyond the resolution limit of fluorescent microscopy, thus impeding research on nucleus architecture, transcription, translation and DNA repair. Recent development in super-resolution fluorescence microscopy enables us to more easily observe objects at the nanometre scale and allows the study of complex cellular structures at unprecedented detail. This review focuses on the application of stimulated emission depletion microscopy for imaging two main components of the chromatin-DNA and the proteins interacting with it.
Understanding the mechanisms of electroplasticity from a crystal plasticity perspective
Authors: Lahiri Arka , Shanthraj Pratheek , Roters Franz
Published: September 2019

Electroplasticity is defined as the reduction in flow stress of a material undergoing deformation on passing an electrical pulse through it. The lowering of flow stress during electrical pulsing has been attributed to a combination of three mechanisms: softening due to Joule-heating of the material, de-pinning of dislocations from paramagnetic obstacles, and the electron-wind force acting on dislocations. However, there is no consensus in literature regarding the relative magnitudes of the reductions in flow stress resulting from each of these mechanisms. In this paper, we extend a dislocation density based crystal plasticity model to incorporate the mechanisms of electroplasticity and perform simulations where a single electrical pulse is applied during compressive deformation of a polycrystalline FCC material with random texture. We analyze the reductions in flow stress to understand the relative importance of the different mechanisms of electroplasticity and delineate their dependencies on the various parameters related to electrical pulsing and dislocation motion. Our study establishes that the reductions in flow stress are largely due to the mechanisms of de-pinning of dislocations from paramagnetic obstacles and Joule-heating, with their relative dominance determined by the specific choice of crystal plasticity parameters corresponding to the particular material of interest.
Electronic structure of molecular beam epitaxy grown

1

T

′

-MoTe2 film and strain effect*
Authors: Zhou Xue , Jiang Zeyu , Zhang Kenan , Yao Wei , Yan Mingzhe , Zhang Hongyun , Duan Wenhui , Zhou Shuyun
Published: September 2019

Atomically thin transition metal dichalcogenide films with distorted trigonal (

1

T

′

) phase have been predicted to be candidates for realizing quantum spin Hall effect. Growth of

1

T

′

film and experimental investigation of its electronic structure are critical. Here we report the electronic structure of

1

T

′

-MoTe2 films grown by molecular beam epitaxy (MBE). Growth of the

1

T

′

-MoTe2 film depends critically on the substrate temperature, and successful growth of the film is indicated by streaky stripes in the reflection high energy electron diffraction (RHEED) and sharp diffraction spots in the low energy electron diffraction (LEED). Angle-resolved photoemission spectroscopy (ARPES) measurements reveal a metallic behavior in the as-grown film with an overlap between the conduction and valence bands. First principles calculation suggests that a suitable tensile strain along the a-axis direction is needed to induce a gap to make it an insulator. Our work not only reports the electronic structure of MBE grown

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-MoTe2 films, but also provides insights for strain engineering to make it possible for quantum spin Hall effect.
Effect of transient space–charge perturbation on carrier transport in high-resistance CdZnTe semiconductor*
Authors: Guo Yu , Zha Gang-Qiang , Li Ying-Rui , Tan Ting-Ting , Zhu Hao , Wu Sen
Published: September 2019

The polarization effect introduced by electric field deformation is the most important bottleneck of CdZnTe detector in x-ray imaging. Currently, most of studies focus on electric field deformation caused by trapped carriers; the perturbation of electric field due to drifting carriers has been rarely reported. In this study, the effect of transient space–charge perturbation on carrier transport in a CdZnTe semiconductor is evaluated by using the laser-beam-induced current (LBIC) technique. Cusps appear in the current curves of CdZnTe detectors with different carrier transport performances under intense excitation, indicating the deformation of electric field. The current signals under different excitations are compared. The results suggest that with the increase of excitation, the amplitude of cusp increases and the electron transient time gradually decreases. The distortion in electric field is independent of carrier transport performance of detector. Transient space–charge perturbation is responsible for the pulse shape and affects the carrier transport process.
Geoscience material structures prediction via CALYPSO methodology
Authors: Hermann Andreas
Published: September 2019

Many properties of planets such as their interior structure and thermal evolution depend on the high-pressure properties of their constituent materials. This paper reviews how crystal structure prediction methodology can help shed light on the transformations materials undergo at the extreme conditions inside planets. The discussion focuses on three areas: (i) the propensity of iron to form compounds with volatile elements at planetary core conditions (important to understand the chemical makeup of Earthʼs inner core), (ii) the chemistry of mixtures of planetary ices (relevant for the mantle regions of giant icy planets), and (iii) examples of mantle minerals. In all cases the abilities and current limitations of crystal structure prediction are discussed across a range of example studies.
Application of static network reconfiguration to minimize power consumption from grid for photovoltaic systems
Authors: Suebudom Watcharis , Tayjasanant Thavatchai
Published: September 2019

Photovoltaic (PV) is one of the distributed generation growing worldwide, a proper method to increase the hosting capacity of PV with low cost is becoming an interesting topic. This paper researched how the total grid purchase of power systems can be decreased by applying static network reconfiguration. The problem is formulated as a load flow which aims to minimize the total grid purchase under thermal and voltage constraints. The effectiveness of the approach and the significant benefits obtained by static reconfiguration options in term of total grid purchase are demonstrated using a modified benchmark distribution system. It was found that applying static network reconfiguration to this specific test system with two PVs gave minimum power consumption from grid.
Comparison of fault transient characteristics of inverter-based distributed generators using different control strategies
Authors: Chang Xiao , Xiao Ying , Yang Yunlei , Zhao Jun , Xu Yonghai , Deng Chengjiang
Published: September 2019

The inverter-based distributed generators (IBDG) using different control strategies have different fault transient characteristics, which are the key issue of fault analysis for the distribution networks with IBDGs. To this end, this study analyzes and compares the fault transient characteristics of IBDGs using PQ control, droop control and virtual synchronous generators (VSG) control by PSCAD/EMTDC simulation, and considering the requirements of low-voltage ride through (LVRT) during grid-connected operation. The simulation results demonstrate that under the asymmetric fault condition of distribution networks, the IBDGs using different control strategies can maintain symmetric output. And when fault occurs in the distribution networks, the IBDGs using different control strategies have different transient response rate and overshoot of the output current.
Medium and long-term power quantity check and adjustment method based on power quantity margin
Authors: Huang Guodong , Yang Junfeng , Ding Qiang , Li Min
Published: September 2019

Medium and long-term power trade is increasing, and the adjustable margin of power grid is reducing. Therefore, medium and long-term power quantity security check is necessary. Firstly, a power quantity margin model is constructed, and power quantity constraints and the future state grid model are considered. The power quantity limits of principal parts such as unit and line section are calculated, and quantity adjustment method is given.Then the medium and long-term power quantity check and adjustment are realized through the correlation coefficient matrix. Finally, the actual provincial power grid is taken as an example to verify the effectiveness of the proposed model and method. Through the calculation of the quantity margin by power, the verification of medium and long-term transactions and the control of the safety margin of the power grid are realized.
Study on the transient characteristic measurement system of current transformer
Authors: Jin Qiu , JiangJun Ruan , Jicheng Yu , Shipu Wu , Anlan Mao
Published: September 2019

Nowadays, thirteen ultra-high voltage direct current (UHVDC) transmission projects have commissioned in China, including Jinping-Sunan, Fulong-Fengxian, Yibin-Jinhua project, and so forth. Meanwhile, another two UHVDC transmission projects are under construction. The highest UHVDC voltage level is ±1100kV. The HVDC transmission is superior in high capacity and long transmission distance, and its control response put forward higher requirements for the transient characteristics of DC current transformer. At present, there is no test method and equipment for testing the transient characteristics of the DC current transformer. Therefore, mastering the transient response characteristics of operating DC current transformer remains to be a challenge. In this paper, a transient test system of DC current transformer is developed, which includes a step current output unit, a high precision acquisition unit and a calibrator algorithm. The system was used to test the rising time, maximum overshoot and transient delay of the DC current transformers installed on the pole line and valve outlet. This study can clarify the influence factors of the transient characteristics of DC transformer on the control and protection system of UHVDC, and can define the principle of selecting the transformer parameters to meet the requirements of the control and protection system of UHVDC. The results of this study have great significance to improve the performance of UHVDC control and protection system.
Research on the influence of live replacement for transformers on the distribution grid and its optimization method
Authors: Wang Binwu , Li Lidong , Liu Jian , Jiang Chunyang , Liu Kun
Published: September 2019

Live replacement of transformers could realize a more convenient way for overhaul and maintenance for this importance equipment in distribution networks. However, a series of harmful impact of transient process may be introduced into the transformer itself and the power distribution system, which would affect accurate measurement and stable operation of the grid. A PSCAD-based simulation model of live replacement for transformers is presented in this paper, and the corresponding method of optimization is also proposed. The scheme presented here is proved to realize live replacement on site, which is significant for improving the level of live maintenance automation and reliability of power distribution systems.
A study of characteristic extraction for transformer oscillation wave based on DWT analysis
Authors: Hongwen Liu , Ke Wang
Published: September 2019

In order to improve the reliability of transformer winding state evaluation method, the analysis of oscillation wave based on high voltage direct current (HVDC) power supply is proposed. Firstly, different noise reduction methods are adopted dealing with the measured oscillation wave data, and a suitable noise reduction method for field experiments is obtained. Then the discrete wavelet transform (DWT) is applied on denoising data. Finally, the characteristics that can be used to evaluate the state of windings are obtained by analysing the wavelet detailed signals. The results show that the waveform characteristics of windings obtained by discrete wavelet transform have good repeatability and can reflect the differences between different windings.
Study on harmonic characteristics and optimization of multi-stage magnetic valve controllable reactor
Authors: Li Qingbo , Zhang Dandan , Chen Junqin , Yang Ruilin
Published: September 2019

This paper proposes a multi-stage magnetic valve controllable reactor based on the traditional magnetic valve controllable reactor (MCR). According to the structural characteristics of multi-stage magnetic valve, the mathematical model of harmonic characteristics of multi-stage MCR device is established, and the cross-section parameters of each magnetic valve are optimized by immune algorithm. The results show that after the number of magnetic valve stages exceeds 3, the optimization of total harmonics is reduced, and both are lower than the national common harmonic standard. Finally, the established mathematical model is verified by simulation. The results show that the three-stage and above magnetic valve structure can control the harmonic current under the national standard. The four-stage MCR can suppress the harmonics well and improve the power quality input to the distribution network.
Output power stabilization control strategy of WPT systems based on secondary side circuit
Authors: Bo Bin , Xu Changfu , Zhang Ming , Wang Ruoyin , Xu Jiayuan
Published: September 2019

In the wireless power transfer (WPT) system, the output power is sensitive to the change of mutual inductance and load resistance. It is necessary to keep the output power stable quickly through effective control methods when the receiving coil and transmitting coil are offset or the load equivalent impedance changes. Based on the analysis of the WPT system with DC/DC converter on the secondary side, the relationship between mutual inductance and load voltage and load current, as well as the relationship between duty cycle of DC/DC converter and load demand power are given. A mutual inductance identification method based on load voltage and load current detection is proposed to monitor mutual inductance changes in real time. The output power stability control strategy based on DC/DC converter is also proposed. Finally, the effectiveness and correctness of the theoretical analysis and control strategy in this paper were verified by simulation and experiment.
Research on fuzzy PID lower extremity exoskeleton control system based on pneumatic drive
Authors: Zhu Songqing , Han Yali , Zhang Meng , Shen Pei , Wu Zhenyu
Published: September 2019

The lower extremity rehabilitation exoskeleton based on pneumatic muscle actuator was introduced. The gait experiments were implemented, and the biomechanics of human walking were outputted for the design and control of lower rehabilitation exoskeleton. The experiment platform was built based on DSPACE system and the fuzzy adaptive PID controller was applied for the control of lower rehabilitation exoskeleton. The experiment results showed that adding the pre-feedback control based on fuzzy adaptive PID can significantly reduce the time that the system, and the experiment of swing control also showed that a high level of coordination between the user swing motion and the exoskeleton leg.
Logistics system planning for battery-powered electric vehicle charging station networks
Authors: Hayajneh Hassan , Salim Muath Bani , Bashetty Srikanth , Zhang Xuewei
Published: September 2019

This work proposes a promising scenario of large-scale deployment of battery-powered electric vehicle charging station networks that attempts to address three important issues toward a sustainable energy landscape in the near future: (1) Suppressed grid integration of variable renewable generations such as wind; (2) Low profitability of battery energy storage systems due to limited applications; and (3) Conflicts between the current power infrastructure and the installation of charging stations to meet the growing needs of electrical transportation. More specifically, we design a system in which electric trucks deliver large-volume batteries to electric vehicle charging stations. This facilitates the planning and operation of electric vehicle charging station networks without constraints from the grid. In regions where there are abundant renewable energy sources and the road networks do not suffer from frequent congestion, this could be a viable solution. Using the city of Corpus Christi, Texas (USA) and the nearby Chapman Ranch wind farm as a test case, we formulate the design problem based on the logistics system models and obtain the optimal sizes of charging station batteries and number of electric trucks to minimize cost. The obtained results can help potential stakeholders make business decisions or policy recommendations.