bluuebunny/crossref_metadata_2025 huggingface dataset:
Modernizing and designing evaluation frameworks for connected sensor technologies in medicine
Authors: Coravos Andrea , Doerr Megan , Goldsack Jennifer , Manta Christine , Shervey Mark , Woods Beau , Wood William A.
Published: March 2020

This manuscript is focused on the use of connected sensor technologies, including wearables and other biosensors, for a wide range of health services, such as collecting digital endpoints in clinical trials and remotely monitoring patients in clinical care. The adoption of these technologies poses five risks that currently exceed our abilities to evaluate and secure these products: (1) validation, (2) security practices, (3) data rights and governance, (4) utility and usability; and (5) economic feasibility. In this manuscript we conduct a landscape analysis of emerging evaluation frameworks developed to better manage these risks, broadly in digital health. We then propose a framework specifically for connected sensor technologies. We provide a pragmatic guide for how to put this evaluation framework into practice, taking lessons from concepts in drug and nutrition labels to craft a connected sensor technology label.
Single-cell RNA sequencing reveals a heterogeneous response to Glucocorticoids in breast cancer cells
Authors: Hoffman Jackson A. , Papas Brian N. , Trotter Kevin W. , Archer Trevor K.
Published: March 2020

Steroid hormone receptors such as the Glucocorticoid Receptor (GR) mediate transcriptional responses to hormones and are frequently targeted in the treatment of human diseases. Experiments using bulk populations of cells have provided a detailed picture of the global transcriptional hormone response but are unable to interrogate cell-to-cell transcriptional heterogeneity. To examine the glucocorticoid response in individual cells, we performed single cell RNA sequencing (scRNAseq) in a human breast cancer cell line. The transcriptional response to hormone was robustly detected in individual cells and scRNAseq provided additional statistical power to identify over 100 GR-regulated genes that were not detected in bulk RNAseq. scRNAseq revealed striking cell-to-cell variability in the hormone response. On average, individual hormone-treated cells showed a response at only 30% of the total set of GR target genes. Understanding the basis of this heterogeneity will be critical for the development of more precise models of steroid hormone signaling.
Podosome formation promotes plasma membrane invagination and integrin-β3 endocytosis on a viscous RGD-membrane
Authors: Cao Fakun , Zhou Yuhuan , Liu Xiaoting , Yu Cheng-han
Published: March 2020

Integrin receptors orchestrate cell adhesion and cytoskeletal reorganization. The endocytic mechanism of integrin-β3 receptor at the podosome remains unclear. Using viscous RGD-membrane as the model system, here we show that the formation of podosome-like adhesion promotes Dab2/clathrin-mediated endocytosis of integrin-β3. Integrin-β3 and RGD ligand are endocytosed from the podosome and sorted into the endosomal compartment. Inhibitions of podosome formation and knockdowns of Dab2 and clathrin reduce RGD endocytosis. F-actin assembly at the podosome core exhibits protrusive contact towards the substrate and results in plasma membrane invaginations at the podosome ring. BIN1 specifically associates with the region of invaginated membrane and recruits DNM2. During the podosome formation, BIN1 and DNM2 synchronously enrich at the podosome ring and trigger clathrin dissociation and RGD endocytosis. Knockdowns of BIN1 and DNM2 suppress RGD endocytosis. Thus, plasma membrane invagination caused by F-actin polymerization promotes BIN1-dependent DNM2 recruitment and facilitate integrin-β3 endocytosis at the podosome.
Absence of Y-pocket in 1-Fe Brillouin zone and reversed orbital occupation imbalance in FeSe
Authors: Huh S. S. , Seo J. J. , Kim B. S. , Cho S. H. , Jung J. K. , Kim S. , Kwon C. I. , Kim Jun Sung , Koh Y. Y. , Kyung W. S. , Denlinger J. D. , Kim Y. H. , Chae B. N. , Kim N. D. , Kim Y. K. , Kim C.
Published: March 2020

The FeSe nematic phase has been the focus of recent research on iron-based superconductors (IBSs) due to its unusual properties, which are distinct from those of the pnictides. A series of theoretical/experimental studies were performed to determine the origin of the nematic phase. However, they yielded conflicting results and caused additional controversies. Here, we report the results of angle-resolved photoemission and X-ray absorption spectroscopy studies on FeSe detwinned by a piezo stack. We fully resolved band dispersions with orbital characters near the Brillouin zone (BZ) corner, and revealed an absence of any Fermi pocket at the Y point in the 1-Fe BZ. In addition, the occupation imbalance between $${d}_{{xz}}$$

d

x
z

and $${d}_{{yz}}$$

d

y
z

orbitals was the opposite of that of iron pnictides, consistent with the identified band characters. These results resolve issues associated with the FeSe nematic phase and shed light on the origin of the nematic phase in IBSs.
Effects of different surface functionalization on the electronic properties and contact types of graphene/functionalized-GeC van der Waals heterostructures
Authors: Vu Tuan V. , Dao Tan Phat , Idrees M. , Phuc Huynh V. , Hieu Nguyen N. , Binh Nguyen T. T. , Dinh Hoi B. , Amin B. , Nguyen Chuong V.
Published: March 2020

Constructing vertical heterostructures by placing graphene (Gr) on two-dimensional materials has recently emerged as an effective way to enhance the performance of nanoelectronic and optoelectronic devices.
Unprecedented coupling reaction between two anionic species of a closo-decahydrodecaborate cluster and an Anderson-type polyoxometalate
Authors: Diab Manal , Mateo Ana , Al Cheikh Joumada , Haouas Mohamed , Ranjbari Alireza , Bourdreux Flavien , Naoufal Daoud , Cadot Emmanuel , Bo Carles , Floquet Sébastien
Published: March 2020

A new family of hybrid polyoxometalates associating anionic decahydrodecaborate clusters with Anderson-type polyoxometalate.
Spin-crossover in an organic–inorganic hybrid perovskite
Authors: Wu Wei-Wei , Wu Si-Guo , Chen Yan-Cong , Huang Guo-Zhang , Lyu Bang-Heng , Ni Zhao-Ping , Tong Ming-Liang
Published: March 2020

The first spin-crossover complex with an organic–inorganic hybrid perovskite structure is reported, which displays three-step spin-crossover, light-induced excited spin-state trapping and spin-state dependent fluorescence properties.
Photoresponsive 2D polymeric Langmuir–Blodgett films of 2,3,6,7,10,11-hexaiminotriphenylene
Authors: Su Liangmei , Xu Fan , Chen Jiawei , Cao Yang , Wang Cheng
Published: March 2020

A photoelectric polymeric film of 2,3,6,7,10,11-hexaiminotriphenylene (HATP) was prepared via aerobic oxidative polymerization using Langmuir–Blodgett (LB) technique.
Biomass-derived Fe-NC hybrid for hydrogenation with formic acid: control of Fe-based nanoparticle distribution
Authors: Liu Lu , Wang Bowei , Gao Ruixiao , Zhang Dan , Xu Wensheng , Chen Ligong , Yan Xilong , Li Yang
Published: March 2020

A series of iron-based, N-doped carbon catalysts exhibits excellent activity in catalytic transfer hydrogenation of nitroarenes without base additive.
Inflammation: major denominator of obesity, Type 2 diabetes and Alzheimer’s disease-like pathology?
Authors: Kacířová Miroslava , Zmeškalová Anna , Kořínková Lucia , Železná Blanka , Kuneš Jaroslav , Maletínská Lenka
Published: March 2020

Adipose tissue is an active metabolic organ that contributes to processes such as energy storage and utilization and to the production of a number of metabolic agents, such as adipokines, which play a role in inflammation. In this review, we try to elucidate the connections between peripheral inflammation at obesity and Type 2 diabetes and the central inflammatory process. Multiple lines of evidence highlight the importance of peripheral inflammation and its link to neuroinflammation, which can lead to neurodegenerative diseases such as dementia, Alzheimer’s disease (AD) and Parkinson’s disease. In addition to the accumulation of misfolded amyloid beta (Aβ) peptide and the formation of the neurofibrillary tangles of hyperphosphorylated tau protein in the brain, activated microglia and reactive astrocytes are the main indicators of AD progression. They were found close to Aβ plaques in the brains of both AD patients and rodent models of Alzheimer’s disease-like pathology. Cytokines are key players in pro- and anti-inflammatory processes and are also produced by microglia and astrocytes.

The interplay of seemingly unrelated pathways between the periphery and the brain could, in fact, have a common denominator, with inflammation in general being a key factor affecting neuronal processes in the brain. An increased amount of white adipose tissue throughout the body seems to be an important player in pro-inflammatory processes. Nevertheless, other important factors should be studied to elucidate the pathological processes of and the relationship among obesity, Type 2 diabetes and neurodegenerative diseases.
Task offloading, load balancing, and resource allocation in MEC networks
Authors: Li S.L. , Du J.B. , Zhai D.S. , Chu X.L. , Yu F.R.
Published: March 2020

To prolong the time duration of smart mobile devices (SMDs) or enable low‐latency tasks, mobile edge computing (MEC) has emerged as a promising paradigm by offloading tasks to nearby MEC servers (MECSs). In this study the authors propose an optimisation problem to minimise the weighted sum of the total delay and energy consumption of all SMDs in a multi‐MECS‐multi‐SMD network via multi‐dimensional optimisation on offloading strategy making, load balancing, computation resource allocation and transmit power control. Since the problem is NP‐hard, the authors decompose it into three subproblems to solve. First, they propose a low complexity heuristic algorithm to obtain the offloading strategies while guaranteeing load balancing between the multiple MECSs. Then they solve computation resource allocation subproblem using Lagrange dual decomposition. Finally, employing fractional programming, the authors transform the transmit power control subproblem into a convex programming problem where the closed‐form solution is obtained. The proposed simulation results verify the convergence of the proposed iterative algorithms, and demonstrate that the proposed joint optimisation could achieve good performance in both delay and energy reduction.
Joint optimal resource allocation schemes for downlink cooperative cellular networks over orthogonal frequency division multiplexing carriers
Authors: Kaveh Fatemeh , Soleimanpour Mohadese , Talebi Siamak
Published: March 2020

This study concentrates on the study of a downlink cooperative cellular (DCC) network in which an access point is located in the centre of each cell and two relay stations are installed in the border between both sectors of a cell to obtain higher cell‐edge throughput. To optimise the network efficiency, a joint optimal subcarrier and power allocation scheme is proposed which initially derives the highest achievable rate for a single‐legacy user (LU), then, through further evaluation and analysis, this is generalised to the case of a multiple‐LU environment. Next, to maximise the overall throughput and ensure fairness, a multi‐objective lexicographical optimisation problem (MLOP) is formulated to maximise the minimum LUs rate while improving the overall throughput. As the proposed MLOP is a mixed‐integer non‐linear problem, finding optimal solutions is impractical and in general, there is no standard method for optimally obtaining a solution. Hence, two efficient algorithms are introduced in this study. Simulation results confirm that the proposed algorithms achieve a fair and near‐optimal performance for the multi‐LU DCC network based on two relay channels, which makes them desirable in practice compared to some of the sub‐optimal well‐known algorithms investigated in this study.
Depth estimation for advancing intelligent transport systems based on self‐improving pyramid stereo network
Authors: Tian Yanling , Du Yubo , Zhang Qieshi , Cheng Jun , Yang Zhuo
Published: March 2020

In autonomous driving, stereo vision‐based depth estimation technology can help to estimate the distance of obstacles accurately, which is crucial for correctly planning the path of the vehicle. Recent work has formulated the stereo depth estimation problem into a deep learning model with convolutional neural networks. However, these methods need a lot of post‐processing and do not have strong adaptive capabilities to ill‐posed regions or new scenes. In addition, due to the difficulty of the labelling the ground truth depth for real circumstance, training data for the system is limited. To overcome the above problems, the authors came up with self‐improving pyramid stereo network, which can not only get a direct regression disparity without complicated post‐processing but also be robust in ill‐posed area. Moreover, by online learning, the proposed model can not only address the data limitation problem but also save the time spent on training and hardware resources in practice. At the same time, the proposed model has a self‐improving ability to new scenes, which can quickly adjust the model according to the test data in time and improve the accuracy of prediction. Experiments on Scene Flow and KITTI data set demonstrate the effectiveness of the proposed network.
GNSS velocimeter by adaptively combining carrier phase and Doppler measurements
Authors: Zhang Laihong , Chang Guobin , Chen Chao , Zhang Siyu , Zhu Ting
Published: March 2020

In order to use a stand‐alone global navigation satellite system (GNSS) receiver to determine the stable instantaneous velocity, a new hybrid GNSS velocimetry approach combining carrier phase and Doppler measurements is proposed. This is a data fusion problem. The problem is expressed as a state‐space model, in which the deviation between the average velocity determined by the time difference carrier phase approach and the instantaneous velocity is represented by the uncertainty of the state model. In kinematic applications, this uncertainty is often variant and hard to be known in advance, a predefined process noise level of the state model is often not sufficiently accurate in the whole working time. Here, an adaptive Kalman filtering approach is employed to fix this problem. To verify the proposed approach, one static experiment and two dynamic experiments with different sampling intervals are performed, separately. All results demonstrate the validity and stability of the proposed approach.
A degree-100 lunar gravity model from the Chang’e 5T1 mission
Authors: Yan Jianguo , Liu Shanhong , Xiao Chi , Ye Mao , Cao Jianfeng , Harada Yuji , Li Fei , Li Xie , Barriot Jean-Pierre
Published: March 2020

Context.Chinese lunar missions have grown in number over the last ten years, with an increasing focus on radio science investigations. In previous work, we estimated two lunar gravity field models, CEGM01 and CEGM02. The recently lunar mission, Chang’e 5T1, which had an orbital inclination between 18 and 68 degrees, and collected orbital tracking data continually for two years, made an improved gravity field model possible.

Aims.Our aim was to estimate a new lunar gravity field model up to degree and order 100, CEGM03, and a new tidal Love number based on the Chang’e 5T1 tracking data combined with the historical tracking data used in the solution of CEGM02. The new model makes use of tracking data with this particular inclination, which has not been used in previous gravity field modeling.

Methods.The solution for this new model was based on our in-house software, LUGREAS. The gravity spectrum power, post-fit residuals after precision orbit determination (POD), lunar surface gravity anomalies, correlations between parameters, admittance and coherence with topography model, and accuracy of POD were analyzed to validate the new CEGM03 model.

Results.We analyzed the tracking data of the Chang’e 5T1 mission and estimated the CEGM03 lunar gravity field model. We found that the two-way Doppler measurement accuracy reached 0.2 mm s−1with 10 s integration time. The error spectrum shows that the formal error for CEGM03 was at least reduced by about 2 times below the harmonic degree of 20, when compared to the CEGM02 model. The admittance and correlation of gravity and topography was also improved when compared to the correlations for the CEGM02 model. The lunar potential Love numberk2was estimated to be 0.02430±0.0001 (ten times the formal error).

Conclusions.From the model analysis and comparison of the various models, we identified improvements in the CEGM03 model after introducing Chang’e 5T1 tracking data. Moreover, this study illustrates how the low and middle inclination orbits could contribute better accuracy for a low degree of lunar gravity field.
Peritonealdialyse in den USA
Authors: Alscher Mark Dominik
Published: March 2020

In der Einleitung der Studie gehen die Autoren darauf ein, dass mittlerweile über 700 000 Bürger der Vereinigten Staaten einen Nierenersatz erhalten. Sie führen aus, dass die Lebensqualität für PD-Patienten (PD: Peritonealdialyse) höher sei, eine niedrigere Rate an Komplikationen auftreten würde und die Kosten für die Gemeinschaft geringer seien. Weiter beschreiben Sloan et al., dass nach Einschätzung der Nephrologen etwa die Hälfte der Patienten für die PD geeignet wäre. Obwohl diese Vorteile klar wären, würden nur 7,6 % aller Patienten in den Vereinigten Staaten die PD durchführen (Stand der Zahlen: Jahr 2010).
Skill- und Grade-Mix in der Pflege (Teil 1)
Authors: Gumpenberger Franz
Published: March 2020

Das gesamte Gesundheitswesen in Österreich befindet sich derzeit in einem markanten Wandel. Soziodemografische Entwicklungen mit einer Zunahme der Zahl von chronischen Erkrankungen, neue medizinische Errungenschaften sowie verkürzte Krankenhausaufenthalte und die damit verbundene steigende Leistungsdichte verlangen von allen Berufsgruppen im Gesundheitswesen fundierte Fachkenntnisse und außerordentliche Fähigkeiten. Dazu werden Diskussionen über die Finanzierbarkeit und Personalengpässe aller Professionen geführt. Geänderte Rahmenbedingungen im Gesundheits- und Krankenpflegegesetz in Österreich eröffnen dahingehend aber neue Zuständigkeits- und Kompetenzbereiche für Pflegende. So wurden neben dem gehobenen Dienst für Gesundheits- und Krankenpflege auch die Berufsgruppen der Pflegeassistenz und der Pflegefachassistenz etabliert. Um eine langfristige und hochwertige pflegerische Versorgung in Gesundheitseinrichtungen gewährleisten zu können, müssen künftig Neuanpassungen der Aufgabenbereiche oder auch Tätigkeitsverschiebungen innerhalb dieser Berufsgruppen stattfinden. Überlegungen, wer welche Tätigkeiten verrichtet, müssen künftig in einem konzeptgeleiteten Skill- und Grade-Mix angestellt werden. Auch im Versorgungsbereich der Dialysestation eines Krankenhauses sind solche Überlegungen unumgänglich und mögliche Zukunftsmodelle richtungsweisend.
Microvascular Effects of Echinodorus grandiflorus on Cardiovascular Disorders
Authors: Gomes Fabiana , Marques André M. , Nathalie Obadia , Lessa Marcos Adriano , Tibiriçá Eduardo , Figueiredo Maria Raquel , Estato Vanessa
Published: March 2020

Echinodorus grandiflorus is a semiaquatic plant native to Brazil and belongs to the Alismataceae family. Infusion preparations of the leaves of this plant are often used due to its diuretic, blood pressure lowering, and anti-inflammatory properties. Our aim was to investigate the effects of chronic treatment with the crude hydroalcoholic extract of E. grandiflorus on central and peripheral microvascular changes induced in a model of hypertension and diabetes. The hemodynamic and microvascular effects of E. grandiflorus extract (50, 100, or 200 mg/kg/day for 28 days) or the isolated major diterpene from E. grandiflorus (3 to 10 mg/kg i. v.) were evaluated in spontaneously hypertensive rats using tail plethysmography and intravital fluorescence videomicroscopy, respectively, and were compared to vehicle-treated normotensive Wistar-Kyoto rats. We also investigated the protective effects of chronic treatment with E. grandiflorus (100 mg/kg/day) in brain capillary density and leukocyte-endothelium interactions on the brain vessels of DM-spontaneously (DM: diabetes mellitus) hypertensive rats. Chronically treating spontaneously hypertensive rats with increasing doses of crude hydroalcoholic E. grandiflorus extract resulted in significant dose-dependent reductions in systolic blood pressure and an anti-inflammatory effect on the brain microcirculation of DM-spontaneously hypertensive rat animals. Using laser speckle contrast imaging, we observed that intravenous administration of the major isolated clerodane diterpene metabolite (1 – 10 mg/kg) increased microvascular blood flow by 25% in spontaneously hypertensive rat skeletal muscle. The results of this study show that E. grandiflorus extracts can be useful in the prevention and reduction of microcirculatory damage in arterial hypertension and other diseases that involve microvascular dysfunction.
Angiotensin II Type 1 Receptor Autoantibodies in Primary
Aldosteronism
Authors: Meyer Lucie S. , Gong Siyuan , Reincke Martin , Williams Tracy Ann
Published: March 2020

Primary aldosteronism (PA) is the most common form of endocrine hypertension.
Agonistic autoantibodies against the angiotensin II type 1 receptor
(AT1R-Abs) have been described in transplantation medicine and
women with pre-eclampsia and more recently in patients with PA. Any functional
role of AT1R-Abs in either of the two main subtypes of PA
(aldosterone-producing adenoma or bilateral adrenal hyperplasia) requires
clarification. In this review, we discuss the studies performed to date on
AT1R-Abs in PA.
Multiple Pulp Stones: A Case Report
Authors: Ozkalayci Nurhat , Zengin A Zeynep , Turk Selma Elekdag , Sumer A Pinar , Bulucu Bilinc , Kirtiloglu Tugrul
Published: March 2020

Pulp stones are usually found in the pulp chamber. Radiographically, they appear as radiopaque structures in the pulp chambers or root canals of individual teeth. Generalized pulp stones throughout the dentition are usually associated with systemic or genetic disorders of the dentine. This report presents an unusual case of a 13-year-old girl with generalized pulp stones with clinically normal crowns. The patient’s main complaint was a crossbite affecting all permanent canines. Radiographic examination revealed multiple pulp stones and several teeth with atypically shaped roots. Orthodontic treatment, gingivoplasty, and esthetic restorations were performed, thus using a multidisciplinary approach to establish functionally and esthetically sound dentition. (Eur J Dent 2011;5:210-214)
The Impact of Polymerization Technique and Glass-Fiber Reinforcement on the Flexural Properties of Denture Base Resin Material
Authors: Al-Thobity Ahmad M.
Published: March 2020

Objective Different polymerization and reinforcement techniques have been tested to enhance the mechanical characteristics of denture base acrylic resins. The goal of the present study was to evaluate the influence of autoclave polymerization techniques with glass fiber reinforcement on the flexural strength and elastic modulus of polymethyl methacrylate denture base resins.

Materials and Methods Ninety specimens were fabricated from heat-polymerized acrylic resin and randomly distributed depending on the polymerization technique into three groups (n = 30): water bath polymerization, short-cycle autoclave polymerization, and long-cycle autoclave polymerization. Each group was further divided into three subgroups (n = 10) based on the concentration of glass fiber 0, 2.5, and 5wt%. The flexural strength and elastic modulus were investigated using a universal testing machine. One-way ANOVA and Tukey’s post hoc test were performed to analyze the results (α = 0.05).

Results The flexural strength and elastic modulus values were significantly higher in 5wt% glass fiber reinforced long-cycle autoclave group in comparison with the other test groups (p < 0.05).

Conclusions The long-cycle autoclave polymerization technique with the glass fiber reinforcement significantly increased the flexural strength and elastic modulus of the denture base resin material.
In Vitro Evaluation of Physical and Mechanical Properties of Light-Curing Resin Cement: A Comparative Study
Authors: Espíndola-Castro Luís Felipe , Brito Oscar Felipe Fonseca de , Araújo Larissa Gabrielle Assis , Santos Izabella Luiza Aragão , Monteiro Gabriela Queiroz De Melo
Published: March 2020

Objective The aim of study was to evaluate in vitro the surface hardness, sorption, solubility, and color stability of three light-cured resin cements, namely RelyX Veneer (RLX), Variolink Veneer (VLK), and All Cem Veneer (ACV).

Materials and Methods Cylindrical samples (15 × 1 mm) were made for each group using a metallic mold (n = 10). Vickers microhardness test was performed, and average hardness was calculated from three indentations (300 gf/15s) per sample. The sorption and solubility of the materials were evaluated according to ISO 4049:2009 based on three samples weighing: initial (m
1), after immersion in distilled water for 7 days (m
2), and final (after removal of all moisture [m
3]). The color change was observed using a digital spectrophotometer, at three different time points, baseline, 1 day, and 1 week of immersion in coffee and distilled water (control).

Statistical Analysis Shapiro–Wilk test was used to analyze the normality of the data, and groups were compared using Kruskal–Wallis and Mann–Whitney tests. A significance level of 5% was used.

Results RLX showed the highest microhardness mean values (36.96 VHN), but higher sorption (23.2 µg/mm3) and solubility (2.40 µg/mm3), with statistically significant differences with the other groups. For color stability, higher ∆E was observed for the samples immersed in coffee (p = 0.009). The VLK resin cement presented statistically significant differences from the other groups, with higher color changes in coffee at 1 day (15.14) and after 1 week (23.65).

Conclusion RLX resin cement showed better hardness results. All materials tested performed satisfactorily for sorption and solubility according to ISO 4049:2009. All materials showed high-staining values after 1 week of immersion in coffee.
X-ray cabinet to deliver highly characterized low-dose soft x-ray radiation to biological samples
Authors: Sengupta Bishwambhar , Medlin Donald , Sprunk Michael , Napolitano Justin , D’Avanzo Jaclyn , Ran Zheng Xiao , Dean Delphine , Takacs Endre
Published: March 2020

We have designed, built, and tested a climate-controlled, radiation-shielded incubator cabinet for the purpose of analyzing the effects of low-dose x-ray radiation on biological tissues and cell cultures. Bremsstrahlung x rays incident on exchangeable fluorescence plates produce strong, quasi-monochromatic radiation directed toward a small container of biological samples. The x-ray source, sample, and detector are enclosed in an incubator—maintaining the optimal environment for biological samples to increase longevity to a maximum of 72 h. To demonstrate the capabilities of the setup, an example experiment is presented. Rat vascular smooth muscle cell growth was observed after irradiation with characteristic x rays of iron, copper, and calcium to impart doses of 2 mGy each. Cultures show significant spectrum dependent increases in cell number over controls at 48 h after irradiation. The experiment lends credence to the efficacy of the apparatus and shows promise for future low-dose bio-radiation studies.
Whence Z-pinches? A personal view
Authors: Pereira N. R.
Published: March 2020

The first Dense Z-Pinch (DZP) conference, in 1984, marked an attempt to use then-modern pulsed power with a Z-pinch to work toward thermonuclear fusion energy. This 11th DZP conference in China is a good time to look back, to comment on progress since, and to project forward. What follows is a personal perspective: scattered comments from a sympathetic outsider and one-time participant. In these 35 years, Z-pinch theory has evolved from little more than cartoons to fully 3D MHD computer simulations, measurements have gone from mostly time- and spatially integrated diagnostics to monochromatic imaging, highly resolved x-ray spectroscopy, and active laser probing. Large pulsed power generators now drive x-ray-producing Z-pinches that are powerful enough for many applications; thermonuclear fusion may work single-shot in the future.
Study of Coulombic broadening in stand-alone ion mobility spectrometry
Authors: Wang Weiguo , Huang Wei , Chen Chuang , Cang Huaiwen , Li Haiyang
Published: March 2020

This paper proposes a method for investigating the Coulombic broadening, tcou, in an ambient pressure ion mobility spectrometer based on the analysis of peaks originating from O2−(H2O)n and electrons. It showed that the full width at half maximum (FWHM) of electrons was independent of electron density and remained at a constant contribution from the initial width of ion packets, tg, and amplifier broadening, tamp; in contrast, the FWHM of O2−(H2O)n increased with the rise of O2−(H2O)n density due to additional contributions from tcou and diffusion broadening tdiff. The tcou of O2−(H2O)n was extracted from the FWHM by subtracting tg, tamp, and tdiff. The tcou of O2−(H2O)n was found to increase from 0.14 ms to 0.24 ms as the O2−(H2O)n density increased from 7.35 × 105 to 1.22 × 107 cm−3. The percentage of tcou in the FWHM was in the range of 45%–80%, and the Coulomb-limited resolving power decreased from 70 to 40 as the ion density increased, which indicated that the Coulomb effect was dramatic.
Wavefront shaping in multimode fibers by transmission matrix engineering
Authors: Resisi Shachar , Viernik Yehonatan , Popoff Sebastien M. , Bromberg Yaron
Published: March 2020

We present a new approach for shaping light at the output of a multimode fiber by modulating the transmission matrix of the system rather than the incident light. We apply computer-controlled mechanical perturbations to the fiber and obtain a desired intensity pattern at its output resulting from the changes to its transmission matrix. Using an all-fiber apparatus, we demonstrate focusing light at the distal end of the fiber and dynamic conversion between fiber modes in the few-mode regime. Since in this approach the number of available degrees of control scales with the number of spectral channels and can thus be larger than the number of fiber modes, it potentially opens the door to simultaneous control over multiple inputs and at multiple wavelengths.
Interfacial solvation can explain attraction between like-charged objects in aqueous solution
Authors: Kubincová Alžbeta , Hünenberger Philippe H. , Krishnan Madhavi
Published: March 2020

Over the past few decades, the experimental literature has consistently reported observations of attraction between like-charged colloidal particles and macromolecules in aqueous solution. Examples include nucleic acids and colloidal particles in the bulk solution and under confinement, and biological liquid–liquid phase separation. This observation is at odds with the intuitive expectation of an interparticle repulsion that decays monotonically with distance. Although attraction between like-charged particles can be rationalized theoretically in the strong-coupling regime, e.g., in the presence of multivalent counterions, recurring accounts of long-range attraction in aqueous solution containing monovalent ions at low ionic strength have posed an open conundrum. Here, we show that the behavior of molecular water at an interface—traditionally disregarded in the continuum electrostatics picture—provides a mechanism to explain the attraction between like-charged objects in a broad spectrum of experiments. This basic principle will have important ramifications in the ongoing quest to better understand intermolecular interactions in solution.
Analyzing oxygen and silicon incorporation in GaN microstructures composed of c-planes and angled facets by confocal magneto-photoluminescence microscopy
Authors: Kamiyama Akinori , Kojima Kazunobu , Chichibu Shigefusa F. , Yusa Go
Published: March 2020

Unintentionally doped impurities formed in the microstructures of free-standing GaN grown with facets were studied using confocal magneto-photoluminescence (PL) microscopy. Donor-bound exciton related peaks in PL spectra and their magnetic behavior allowed us to distinguish typical donor impurity atoms, such as silicon and oxygen. Combining this technique with confocal microscopy also revealed the spatial distribution of the impurities. The results showed that angled facets tend to incorporate oxygen. Moreover, even facets angled at a few degrees with respect to the (0001) surface cause a noticeable change in oxygen incorporation on the order of 1 × 1016 cm−3.
Van Gurp–Palmen relations for long-chain branching from general rigid bead-rod theory
Authors: Kanso M. A. , Giacomin A. J.
Published: March 2020

Empirically, we find that parametric plots of mechanical loss angle vs complex shear modulus may depend neither on temperature [M. van Gurp and J. Palmen, “Time-temperature superposition for polymeric blends,” Rheol. Bull. 67, 5–8 (1998)] nor on average molecular weight [S. Hatzikiriakos, “Long chain branching and polydispersity effects on the rheological properties of polyethylenes,” Polym. Eng. Sci. 40, 2279 (2000)]. Moreover, Hatzikiriakos (2000) discovered that, for fixed polydispersity, these van Gurp–Palmen curves descend with long-chain branching content. In this paper, we find that general rigid bead-rod theory [O. Hassager, “Kinetic theory and rheology of bead-rod models for macromolecular solutions. II. Linear unsteady flow properties,” J. Chem. Phys. 60(10), 4001–4008 (1974)] can explain these descents. We explore the effects of branching along a straight chain in small-amplitude oscillatory shear flow. Specifically, we explore the number of branches, branch length, branch position, and branch distribution.
Effect of frequency detuning on Brillouin lasing in microcavities
Authors: Korobko D.A. , Zolotovskii I.O. , Svetukhin V.V. , Zhukov A.V. , Fomin A.N. , Borisova K.V. , Fotiadi A.A.
Published: March 2020

We have theoretically investigated Brillouin lasing in microcavities in the case when the Brillouin shift and the intermode spacing of the microcavity do not coincide. It is shown that, despite the rise of the lasing threshold, a significant increase in the Brillouin signal intensity can be achieved in this case compared to the resonance one. A necessary condition for this effect is to select an optimal value of detuning of the pump radiation frequency from the frequency of the corresponding microcavity mode. The result of increasing the lasing threshold is also a narrowing of the Brillouin signal lasing range in the nonresonant case, which leads to a decrease in the signal noise level provided the detuning value is optimally selected. Analytical calculations are confirmed by the results of numerical modelling.
Femtosecond dynamics of cavity modes in ZnSe films on a metal
Authors: Vinogradov E.A.
Published: March 2020

The ultrafast evolution of cavity modes in a ZnSe film on a metal (Cr, Cu, or Ni) is studied by femtosecond pump/supercontinuum-probe spectroscopy on a time scale of several tens of femtoseconds. Femtosecond excitation of a microcavity in a ZnSe film on a metal substrate leads to a change in the parameters of cavity (Fabry – Perot) modes. The cavity-mode frequency shifts are due to the photoinduced changes in the boundary conditions and the optical thickness of microcavity.
Detection of coherent optical phonons in a thin bismuth film by ultrafast electron diffraction
Authors: Mironov B.N. , Aseyev S.A. , Ischenko A.A. , Kochikov I.V. , Chekalin S.V. , Ryabov E.A.
Published: March 2020

Coherent dynamics of lattice oscillations in a ∼20-nm-thick film obtained by thermal sputtering of bismuth is studied using ultrashort electron bunches synchronised with femtosecond laser pulses irradiating the sample. The Fourier analysis of ultrafast electron diffraction (UED) data shows that the observed modulation of the signal is due to the ensemble of modes corresponding to optical phonons with frequencies of approximately 3, 6 and 9 THz. A conclusion is made that these peaks correspond to the manifestation of the bismuth A
1g mode (three-terahertz peak), as well as its first and second overtones, which is probably due to quantum confinement in a 20-nm Bi nanostructure. The possibility of a detailed study of the quantum-size effect in bismuth with the help of a transmission UED is analysed.
A comparison of urban and peri-urban/hinterland nocturnal birds at Brisbane, Australia
Authors: Fulton Graham R. , Fulton Grace R. , Cheung Yee Wan
Published: March 2020

This study identified and compared the abundance and detectability of owls and other nocturnal birds, over 1 year, in an urban parkland of a Brisbane suburb to a peri-urban/hinterland/rainforest site 27km away. Five owl species were detected, but only at the peri-urban/hinterland/rainforest site, they were powerful owl Ninox strenua, southern boobook Ninox boobook, sooty owl, Tyto tenebricosa, masked owl Tyto novaehollandiae and barn owl Tyto alba. A single southern boobook was detected outside the study, at the urban site. The tawny frogmouth Podargus strigoides was only detected at the urban site whereas the plumed frogmouth Podargus ocellatus plumiferus was only detected at the rainforest site. The bush stone-curlew Burhinus grallarius was the most frequently detected nocturnal species, yet we discuss its recent decline in Brisbane. Incidentally recorded mammals, reptiles, frogs and diurnal birds are given. The rainforest site had more scansorial mammals whereas the urban site had more possums, dogs and cats.
Plastic behaviours during tempering by crystal plasticity analyses using fast Fourier transform
Authors: Yamazaki Yosuke , Otsuka Takayuki , Okamura Kazuo , Shibutani Yoji
Published: March 2020

Heat treatment, such as quenching and carburising, often involves volume change caused by phenomena such as thermal expansion, phase transformation, and carbide precipitation during tempering. During the tempering process, an external force induces additional plastic deformation. The authors termed this phenomenon ‘tempering plasticity’. In this study, we performed crystal plasticity analysis using fast Fourier transform considering the volume change in carbides to assess the mechanism of tempering plasticity. As a result, tempering plastic strain occurred as the volume fraction of carbide increased, and the tempering plastic phenomenon could be reproduced based on the transformation model proposed by Greenwood–Johnson. The result supports the idea that the volume change accompanied by carbide precipitation is an important mechanism that invokes tempering plasticity.
Quantized Superfluid Vortex Filaments Induced by the Axial Flow Effect*
Authors: Li Hao , Liu Chong , Yang Zhan-Ying , Yang Wen-Li
Published: March 2020

We report the quantized superfluid vortex filaments induced by the axial flow effect, which exhibit intriguing loop structures on helical vortexes. Such new vortex filaments correspond to a series of soliton excitations including the multipeak soliton, W-shaped soliton, and anti-dark soliton, which have no analogue when the axial flow effect is absent. In particular, we show that the vortex filaments induced by the multipeak soliton and W-shaped soliton arise from the dual action of bending and twisting of the vortex, while the vortex filament induced by the anti-dark soliton is caused only by the bending action, which is consistent with the case of the standard bright soliton. These results will deepen our understanding of breather-induced vortex filaments and will be helpful for controllable ring-like excitations on vortices.
Soliton Molecules and Some Hybrid Solutions for the Nonlinear Schrödinger Equation*
Authors: Wang Bao , Zhang Zhao , Li Biao
Published: March 2020

Based on velocity resonance and Darboux transformation, soliton molecules and hybrid solutions consisting of soliton molecules and smooth positons are derived. Two new interesting results are obtained: the first is that the relationship between soliton molecules and smooth positons is clearly pointed out, and the second is that we find two different interactions between smooth positons called strong interaction and weak interaction, respectively. The strong interaction will only disappear when t → ∞. This strong interaction can also excite some periodic phenomena.
Diode Pumped Rubidium Laser Based on Etalon Effects of Alkali Cell Windows*
Authors: Ning Fang-Jin , Li Zhi-Yong , Tan Rong-Qing , Hu Lie-Mao , Liu Song-Yang
Published: March 2020

We demonstrate that the etalon effects of alkali cells can be used as the output coupler of an alkali laser. Based on a rubidium cell with highly parallelized windows, a 2.7 W rubidium laser with optical efficiency of 20.9% and slope efficiency of 31.8% is obtained by adopting unconventional output couplers. Since it has compact configuration and the inner surface of the rubidium cell is uncoated, this may be used in high power laser systems with long lifetimes.
Production of 87Rb Bose–Einstein Condensate with a Simple Evaporative Cooling Method*
Authors: Fazal Rehman , Li Jia-Zhen , Chen Zhi-Wen , Qin Yuan , Lin Ya-Yi , Zhang Zuan-Xian , Zhang Shan-Chao , Huang Wei , Yan Hui , Zhu Shi-Liang
Published: March 2020

A Bose–Einstein condensate with a large atom number is an important experimental platform for quantum simulation and quantum information research. An optical dipole trap is the a conventional way to hold the ultracold atoms, where an atomic cloud is evaporatively cooled down before reaching the Bose–Einstein condensate. A carefully designed trap depth controlling curve is typically required to realize the optimal evaporation cooling. We present and demonstrate a simple way to optimize the evaporation cooling in a crossed optical dipole trap. A polyline shape optical power control profile is easily obtained with our method, by which a pure Bose–Einstein condensate with atom number 1.73 × 105 is produced. Theoretically, we numerically simulate the optimal evaporation cooling using the parameters of our apparatus based on a kinetic theory. Compared to the simulation results, our evaporation cooling shows a good performance. We believe that our simple method can be used to quickly realize evaporation cooling in optical dipole traps.
Wafer-scale graphene quality assessment using micro four-point probe mapping
Authors: Mackenzie David M A , Kalhauge Kristoffer G , Whelan Patrick R , Østergaard Frederik W , Pasternak Iwona , Strupinski Wlodek , Bøggild Peter , Jepsen Peter U , Petersen Dirch H
Published: March 2020

Micro four-point probes (M4PP) provide rapid and automated lithography-free transport properties of planar surfaces including two-dimensional materials. We perform sheet conductance wafer maps of graphene directly grown on a 100 mm diameter SiC wafer using a multiplexed seven-point probe with minor additional measurement time compared to a four-point probe. Comparing the results of three subprobes we find that compared to a single-probe result, our measurement yield increases from 72%–84% to 97%. The additional data allows for correlation analysis between adjacent subprobes, that must measure the same values in case the sample is uniform on the scale of the electrode pitch. We observe that the relative difference in measured sheet conductance between two adjacent subprobes increase in the transition between large and low conductance regions. We mapped sheet conductance of graphene as it changed over several weeks. Terahertz time-domain spectroscopy conductivity maps both before and after M4PP mapping showed no significant change due to M4PP measurement, with both methods showing the same qualitative changes over time.
Synergy effect in hybrid nanocomposites based on carbon nanotubes and graphene nanoplatelets
Authors: Gbaguidi Audrey , Namilae Sirish , Kim Daewon
Published: March 2020

Hybrid nanocomposites reinforced with a mixture of graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) have shown improvement in filler dispersion while providing a cost-effective alternative to CNT monofiller composites. Depending on their composition, hybrid composites can exhibit electrical performance superior to either of the constituent monofiller composites due to synergistic effects. In this work, we develop a three-dimensional tunneling-based continuum percolation model for hybrid nanocomposites filled with hardcore particles of elliptical GNPs and cylindrical CNTs. Using Monte Carlo simulations, parametric studies of the filler content, composition and morphology are carried out to analyze the conditions required for synergy in percolation onset and electrical conductivity. Our results suggest that for hybrid systems with well-dispersed fillers, the electrical performance is linked to the number of tunneling junctions per filler inside the percolated network of the nanocomposites. More importantly, hybrid composites filled with specific morphology of GNP and CNT, exhibit synergy in their electrical performance when the monofiller composites of each of those exact fillers have similar percolation onset values. The simulations results are in agreement with relevant experimental data on hybrid nanocomposites.
Acoustic versus electromagnetic field theory: scalar, vector, spinor representations and the emergence of acoustic spin
Authors: Burns Lucas , Bliokh Konstantin Y , Nori Franco , Dressel Justin
Published: March 2020

We construct a novel Lagrangian representation of acoustic field theory that describes the local vector properties of longitudinal (curl-free) acoustic fields. In particular, this approach accounts for the recently-discovered nonzero spin angular momentum density in inhomogeneous sound fields in fluids or gases. The traditional acoustic Lagrangian representation with a scalar potential is unable to describe such vector properties of acoustic fields adequately, which are however observable via local radiation forces and torques on small probe particles. By introducing a displacement vector potential analogous to the electromagnetic vector potential, we derive the appropriate canonical momentum and spin densities as conserved Noether currents. The results are consistent with recent theoretical analyses and experiments. Furthermore, by an analogy with dual-symmetric electromagnetic field theory that combines electric- and magnetic-potential representations, we put forward an acoustic spinor representation combining the scalar and vector representations. This approach also includes naturally coupling to sources. The strong analogies between electromagnetism and acoustics suggest further productive inquiry, particularly regarding the nature of the apparent spacetime symmetries inherent to acoustic fields.