bluuebunny/crossref_metadata_2025 huggingface dataset:
Automatic, wearable-based, in-field eating detection approaches for public health research: a scoping review
Authors: Bell Brooke M. , Alam Ridwan , Alshurafa Nabil , Thomaz Edison , Mondol Abu S. , de la Haye Kayla , Stankovic John A. , Lach John , Spruijt-Metz Donna
Published: March 2020

Dietary intake, eating behaviors, and context are important in chronic disease development, yet our ability to accurately assess these in research settings can be limited by biased traditional self-reporting tools. Objective measurement tools, specifically, wearable sensors, present the opportunity to minimize the major limitations of self-reported eating measures by generating supplementary sensor data that can improve the validity of self-report data in naturalistic settings. This scoping review summarizes the current use of wearable devices/sensors that automatically detect eating-related activity in naturalistic research settings. Five databases were searched in December 2019, and 618 records were retrieved from the literature search. This scoping review included N = 40 studies (from 33 articles) that reported on one or more wearable sensors used to automatically detect eating activity in the field. The majority of studies (N = 26, 65%) used multi-sensor systems (incorporating > 1 wearable sensors), and accelerometers were the most commonly utilized sensor (N = 25, 62.5%). All studies (N = 40, 100.0%) used either self-report or objective ground-truth methods to validate the inferred eating activity detected by the sensor(s). The most frequently reported evaluation metrics were Accuracy (N = 12) and F1-score (N = 10). This scoping review highlights the current state of wearable sensors’ ability to improve upon traditional eating assessment methods by passively detecting eating activity in naturalistic settings, over long periods of time, and with minimal user interaction. A key challenge in this field, wide variation in eating outcome measures and evaluation metrics, demonstrates the need for the development of a standardized form of comparability among sensors/multi-sensor systems and multidisciplinary collaboration.
Ecosystem-wide metagenomic binning enables prediction of ecological niches from genomes
Authors: Alneberg Johannes , Bennke Christin , Beier Sara , Bunse Carina , Quince Christopher , Ininbergs Karolina , Riemann Lasse , Ekman Martin , Jürgens Klaus , Labrenz Matthias , Pinhassi Jarone , Andersson Anders F.
Published: March 2020

The genome encodes the metabolic and functional capabilities of an organism and should be a major determinant of its ecological niche. Yet, it is unknown if the niche can be predicted directly from the genome. Here, we conduct metagenomic binning on 123 water samples spanning major environmental gradients of the Baltic Sea. The resulting 1961 metagenome-assembled genomes represent 352 species-level clusters that correspond to 1/3 of the metagenome sequences of the prokaryotic size-fraction. By using machine-learning, the placement of a genome cluster along various niche gradients (salinity level, depth, size-fraction) could be predicted based solely on its functional genes. The same approach predicted the genomes’ placement in a virtual niche-space that captures the highest variation in distribution patterns. The predictions generally outperformed those inferred from phylogenetic information. Our study demonstrates a strong link between genome and ecological niche and provides a conceptual framework for predictive ecology based on genomic data.
Three for the price of one! Immunodetection of three amphenicols in foodstuffs using a universal standard curve
Authors: Galvidis Inna A. , Eremin Sergei A. , Burkin Maksim A.
Published: March 2020

Florfenicol amine, florfenicol, and thiamphenicol are equally recognized in the developed ELISA and can be quantified using a universal standard curve. These amphenicols approved for livestock use can be distinguished from banned chloramphenicol.
Site specific and localized structural displacements in open structured multimetallic oxides
Authors: Lunkenbein Thomas , Masliuk Liudmyla , Plodinec Milivoj , Algara-Siller Gerardo , Jung Sabrina , Jastak Mateusz , Kube Pierre , Trunschke Annette , Schlögl Robert
Published: March 2020

Picometer-scale displacements of one metal site and their local distribution in open structured (Mo,V,Te,Nb)Oxare described.
Dispersible and manipulable magnetic L10-FePt nanoparticles
Authors: Liu Xin , Wang Hui , Zuo Shulan , Zhang Tianli , Dong Ying , Li Deyao , Jiang Chengbao
Published: March 2020

L10-FePt nanoparticles dispersed by stirring, ultrasonication and the addition of a surfactant perform better than the aggregated nanoparticles, when aligning.
Spectral deep learning for prediction and prospective validation of functional groups
Authors: Fine Jonathan A. , Rajasekar Anand A. , Jethava Krupal P. , Chopra Gaurav
Published: March 2020

A new multi-label deep neural network architecture is used to combine Infrared and mass spectra, trained on single compounds to predict functional groups, and experimentally validated on complex mixtures.
Oleacein inhibits STAT3, activates the apoptotic machinery, and exerts anti-metastatic effects in the SH-SY5Y human neuroblastoma cells
Authors: Cirmi Santa , Celano Marilena , Lombardo Giovanni Enrico , Maggisano Valentina , Procopio Antonio , Russo Diego , Navarra Michele
Published: March 2020

The present findings demonstrate that oleacein, the main secoiridoid of extravirgin olive oil, acts against neuroblastoma cells, by reducing cell adhesion and migration, inducing apoptotic death and modulating STAT3-dependent pathway.
Recyclable electrochemical supercapacitors based on carbon nanotubes and organic nanocrystals
Authors: Yanshyna Oksana , Weissman Haim , Rybtchinski Boris
Published: March 2020

A fully recyclable electrochemical supercapacitor based on carbon nanotube electrodes and organic nanocrystalline dielectric membrane advances a concept of sustainable energy storage materials.
Synthesis of cyclic polymers and flaws of the Jacobson–Stockmayer theory
Authors: Kricheldorf Hans R. , Weidner Steffen M. , Scheliga Felix
Published: March 2020

The results of this study show that even at the highest initial monomer concentration (IMC) complete cyclization of polymer chains can be achieved at 100% conversion.
Efficient synthesis of cyclic amidine-based fluorophoresvia6π-electrocyclic ring closure
Authors: Li Guofeng , Zhao Man , Xie Junqiu , Yao Ying , Mou Lingyun , Zhang Xiaowei , Guo Xiaomin , Sun Wangsheng , Wang Zheng , Xu Jiecheng , Xue Jianzhong , Hu Tao , Zhang Ming , Li Min , Hong Liang
Published: March 2020

Novel 10π-electron cyclic amidines with excellent fluorescence properties were synthesized by a general and efficient 6π-electrocyclic ring closure of ketenimine and imine starting fromN-sulfonyl triazoles and arylamines.
Burkholderia pseudomallei pathogenesis and survival in different niches
Authors: Yip Chee-Hoo , Ghazali Ahmad-Kamal , Nathan Sheila
Published: March 2020

Burkholderia pseudomallei (Bp) is the causative agent of melioidosis, a disease of the tropics with high clinical mortality rates. To date, no vaccines are approved for melioidosis and current treatment relies on antibiotics. Conversely, common misdiagnosis and high pathogenicity of Bp hamper efforts to fight melioidosis. This bacterium can be isolated from a wide range of niches such as waterlogged fields, stagnant water bodies, salt water bodies and from human and animal clinical specimens. Although extensive studies have been undertaken to elucidate pathogenesis mechanisms of Bp, little is known about how a harmless soil bacterium adapts to different environmental conditions, in particular, the shift to a human host to become a highly virulent pathogen. The bacterium has a large genome encoding an armory of factors that assist the pathogen in surviving under stressful conditions and assuming its role as a deadly intracellular pathogen. This review presents an overview of what is currently known about how the pathogen adapts to different environments. With in-depth understanding of Bp adaptation and survival, more effective therapies for melioidosis can be developed by targeting related genes or proteins that play a major role in the bacteria's survival.
Background timing mismatch calibration technique for TIADC in Nyquist frequency band
Authors: Yin Yongsheng , Wan Zhujuan , Chen Hongmei , Liu Lu , Deng Honghui , Meng Xu , Wu Jingsheng
Published: March 2020

A background calibration technique for time‐interleaved analogue‐to‐digital converter (TIADC) over Sub‐Nyquist frequency timing mismatch is proposed. When the input signal only satisfies the Nyquist sampling theorem of the overall TIADC rather than sub‐ADC, both directions of estimation based on correlation and compensation based on differentiator may be opposite to the actual value, which results in a failure calibration. In this Letter, the authors propose a calibration direction correction algorithm which can detect and correct the calibration direction and assure an effective calibration in the whole Nyquist frequency of TIADC. Simulation results show that, for a four‐channel 12‐bit 1 GS/s TIADC, with , signal to noise and distortion ratio (SNDR) is improved from 30.1 to 73.2 dB.
Design and implementation of positioning and control systems for capsule endoscopes
Authors: Mohammed Ibrahim K. , Sharif Bayan S. , Neasham Jeffery A.
Published: March 2020

Wireless capsule endoscope (WCE) is a new diagnostic device that can be utilised for evaluating the whole digestive tract if effectively actuated. In this research, a new one degree of freedom (1DOF) actuation system based on a magnetic levitation concept is proposed for the capsule endoscope navigation system. The proposed system is used to move a permanent magnet inserted in WCE body by an arrangement of the current controlled electromagnetic actuator placed on a 3DOF movable frame. The aim of this study is to design a proportional–integral–derivative (PID) controller to suspend the capsule and keep it at a demand test region. DC and AC magnetic field‐based positioning systems using the Hall effect sensor and the coil sensor, respectively are used to provide the controller by capsule position feedback. Improvement of the position feedback accuracy based on AC magnetic field using discrete Fourier transform is presented. Realistic simulation design of the system is implemented using Matlab/Simulink environment to validate the PID controller. The navigation scheme is implemented practically utilszing digital signal processor to verify the effectiveness of the controller. Finally, simulation and experimental results of the capsule navigation system are presented to show the performance of the proposed controller.
Neural network‐based target‐type flowmeter for high‐velocity liquid flow measurement
Authors: Ali Sayyed Faizan , Maurya Praveen , Mandal Nirupama
Published: March 2020

Target flowmeter is commonly used for measuring flow rates, but there are some shortcomings of the conventional target flowmeter such as complex structure, low sensitivity, non‐linearity. Here, a reluctance‐type target flowmeter has been developed which converts the flow rates into an electrical signal using a modified Maxwell–Wien bridge. Two ferromagnetic cores are used in which one is attached to the target disc and in other core, coils are winded. These two cores along with coils convert the displacement of the target disc into a change in inductance. The change in inductance is converted into an electrical signal using a modified bridge. The electrical output is non‐linear with respect to the flow rate. The electrical output is linearised with the help of a neural network technique. This minimises the non‐linearity error up to 0.27% of full scale output (FSO). This research study includes a theoretical analysis of the proposed flow transmitter. This sensor has been designed and tested for a 0–2000 liters per hour (LPH) range in the laboratory. Experimental studies revealed that the transmitter under investigation possessed linear characteristics and obeyed the theoretical equations.
„Punktionsinfekt“ mit klassischer Symptomatik: Rötung, Schwellung, Schmerzen
Authors: Krönung Gerhard
Published: March 2020

Shuntvenen zeigen nicht selten lokal umschriebene Entzündungszeichen. Meist handelt es sich dabei um eine abakterielle resorptive Entzündung bei parietaler Shuntvenenthrombose und eher selten um einen bakteriellen Punktionsinfekt.
Kongressbericht
Authors: Schrooten Charlotte , Großmann Anne
Published: March 2020

Das wissenschaftliche Programm des Nephrologischen Jahresgespräches startete am Freitag mit 2 Vorsymposien. In diesen wurden mehrere Aspekte der Peritonealdialyse (PD) und der ambulanten fachärztlich-nephrologischen Weiterbildung erörtert.
Hämodialyse
Authors: Beige Joachim
Published: March 2020

Die Wahl des Dialyseverfahrens erfolgt auf der Basis eines umfassenden Aufklärungsgesprächs zwischen Arzt und Patienten über die individuellen Merkmale der einzelnen Verfahren und ihrer Eignung für den Patienten. Das medizinisch beste Nierenersatzverfahren ist die Nierentransplantation, die aus verschiedenen Gründen jedoch nicht immer durchgeführt werden kann. Zwischen den beiden apparativen Dialyseverfahren Hämo- (HD) und Peritonealdialyse (PD) gibt es keine größeren, evidenzgesicherten Unterschiede bzgl. Morbidität und Mortalität, sodass hier neben einigen Ein- und Ausschlusskriterien die Patientenpriorität berücksichtigt werden muss. Zu den Patientenmerkmalen und -wünschen gehören die Auswirkung auf die Alltagsgestaltung, Berücksichtigung der Restdiurese und evtl. seltene Ausschlussmerkmale bei der Zugangswahl. Da die PD in den ersten Jahren nach Dialysestart einen evtl. Mortalitätsvorteil bieten könnte, macht es bei voraussichtlich langer Dialyseabhängigkeit deshalb Sinn, eine „Nierenersatzkarriere“ mit der PD zu beginnen und HD-Verfahren erst später zu nutzen.
Nierentransplantation
Authors: Schuster Antonia , Banas Bernhard , Bergler Tobias
Published: March 2020

Über 60 Jahre nach der ersten langfristig erfolgreichen Nierentransplantation stellt diese heutzutage ein sicheres, etabliertes und effektives Therapiekonzept in der Versorgung terminal dialysepflichtiger Patienten dar. Grundlegende Voraussetzungen für eine erfolgreiche Nierentransplantation sind die Entschlüsselung relevanter immunologischer Fragen, die zunehmenden Möglichkeiten einer optimierten, auf den individuellen Patienten und sein immunologisches und nichtimmunologisches Risikoprofil abgestimmten immunsuppressiven Therapie und eine konsequente, qualifizierte Nachsorge. Gleichwohl gefährden der anhaltende und sich aggravierende Mangel an Spenderorganen und die damit einhergehende Zunahme an Wartezeit nicht nur die erreichbaren Erfolge nach Nierentransplantation, sondern in direkter Konsequenz auch das Leben betroffener Patienten.
Comparative Morpho-Anatomical and HPTLC Profiling of Tinospora Species and Dietary Supplements
Authors: Parveen Abidah , Adams John S. , Raman Vijayasankar , Budel Jane M. , Zhao Jianping , Babu Ganesh N.M. , Ali Zulfiqar , Khan Ikhlas A.
Published: March 2020

Overlapping geographical occurrence, history of traditional use, confusion in species identification, and morphological resemblances among various species are some considerations that necessitate the importance of qualitative analysis for efficient quality control and safer botanical products. This paper provides detailed morpho-anatomies of the leaves and stems of Tinospora cordifolia, Tinospora crispa, and Tinospora sinensis, and stems of Tinospora baenzigeri. Microscopy studies of the selected Tinospora species revealed key diagnostic features that can help distinguish the closely related species of Tinospora as well as to detect any adulteration or substitution in the raw materials. HPTLC profiles of the authenticated plant materials, as well as commercial products claiming to contain Tinospora, were compared to distinguish T. crispa from other closely related species and to establish an efficient method to assess the identity and quality of the products using qualified chemical markers. HPTLC chromatograms of both plant samples and dietary supplements were compared with six reference marker compounds. The analysis revealed that borapetoside B and C were useful to identify T. crispa while tinosineside A was found to be characteristic to authenticate the T. sinensis products.
Effectiveness of Thymoquinone and Fluoridated Bioactive Glass/Nano-Oxide Contained Dentifrices on Abrasion and Dentine Tubules Occlusion: An Ex Vivo Study
Authors: Anthoney Daud , Zahid Shahreen , Khalid Hina , Khurshid Zohaib , Shah Asma Tufail , Chaudhry Aqif Anwar , Khan Abdul Samad
Published: March 2020

Objectives Dentin hypersensitivity (DH) is mainly due to the loss and replenishment of minerals from tooth structure, where the lost minerals can be rehabilitated with a biomimetic approach. The objectives were to determine the relative dentin abrasivity (RDA) of experimental (EXT) dentifrices and to determine the efficacy to occlude dentinal tubules.

Materials and Methods Experimental dentifrices contained nano-fluoridated bioactive glass (n-FBG: 1.5 wt.% [EXT-A], 2.5 wt.% [EXT-B], and 3.5 wt.% [EXT-C]), nano-zinc oxide (n-ZnO), and thymoquinone as active agents. Bovine dentin blocks were subjected to brushing treatments as per groups, that is, distilled water; commercial dentifrice (control, CT); EXT toothpastes; and EXT-D without active agents. Samples were tested for three-dimensional (3D) abrasion analysis according to ISO-11609:2010 (International Organization for Standardization [ISO]). The roughness average (Ra), RDA, surface topography, and elemental compositions were investigated.

Statistical Analysis One-way analysis of variance (ANOVA) with post-hoc Tukey’s and Tamhane’s test was performed for characterizations using Statistical Package for the Social Sciences (SPSS) version 21. The result was considered significant with p-value ≤ 0.05.

Results Comparisons of Ra differed significantly between all groups with p < 0.05 except CT and EXT-A. The RDA values of EXT-A, EXT-B, and EXT-C were calculated as 74.04, 84.26, and 116.24, respectively, which were well within the acceptable limit set by international standards. All n-FBG containing dentifrices demonstrated uniform occlusion of dentinal tubules; however, highly concentrated EXT dentifrices showed more occlusion.

Conclusions Acceptable range of RDA and superior occlusion of tubules by novel dentifrices suggest that it may be recommended for treating DH.
Effects of 1450-ppm Fluoride-containing Toothpastes Associated with Boosters on the Enamel Remineralization and Surface Roughness after Cariogenic Challenge
Authors: Tomaz Pedro Luiz Santos , Sousa Letícia Almeida de , Aguiar Kayanne Freire de , Oliveira Thales de Sá , Matochek Marcelo Henrick Maia , Polassi Mackeler Ramos , D’Alpino Paulo Henrique Perlatti
Published: March 2020

Objectives This in vitro study investigated the remineralization potential of 1450 ppm, fluoride-containing toothpastes containing different active remineralization agents after cariogenic challenge with pH cycling. The enamel surface roughness after brushing and the chemical and physical characteristics of the toothpastes tested were also analyzed.

Materials and Methods Fifty-six bovine enamel blocks were obtained (4 × 4 × 6 mm) and divided into three thirds: intact (untreated), demineralized (artificial caries lesion), and treated (caries lesion, pH cycling, and brushing with dentifrices). Seven commercially available fluoride toothpastes (1450 ppm F): three with anti-erosion claims (Candida Professional [CPP], Colgate Total 12 Daily Repair [CDR], Regenerate Enamel Science [RES]); three with desensitizing claims (Bianco Pro Clinical [BPP], Elmex Sensitive [ESS], and Regenerador Diário DentalClean [RDC]); and one standard regular-fluoride toothpaste Colgate Total 12 (CTT) were selected. During pH cycling (demineralization 6 h/remineralization 18 h) for 7 days, the treated third was brushed with the different dentifrices for 10 minutes in a brushing machine before immersion in a remineralizing solution. The Knoop hardness (25 g, 10 second of the surface, and longitudinal section were then evaluated at eight depths (10 to 330 μm). Mean and percentage of surface hardness recovery (% SHR) were calculated. Surface enamel roughness (Ra) was also evaluated. The pH, %weight of particles, zeta potential, and polydispersity index of toothpaste slurries were also evaluated.

Statistical Analysis Data were statistically analyzed (ANOVA/Tukey, 5%).

Results The %SHR of CPP was significantly lower than the others (p < 0.05). The enamel subsurface was more effectively remineralized when treated with BPP, ESS, and RDC. The surface roughness was higher when the demineralized third was treated with CTT, RDC, and RES and after the cariogenic challenge (p < 0.05). For some of the products tested, there was no relationship between surface remineralization and subsurface remineralization. Although toothpastes CPP and RDC present the lowest %SHR means, both products effectively remineralize within the subsurface carious lesion. Regression analysis demonstrated no strong correlations of the enamel surface roughness with the chemical and physical parameters.

Conclusions Most but not all the fluoride toothpastes were able to remineralize the enamel surface. No specific chemical or physical parameter alone correlated with the surface roughness.
Characterization and experimental validation of a semi-empirical fuel cell model for investigating the water dynamics on the electrical behavior of a 5 kW Ballard stack system using Nafion 117 polymer membrane
Authors: Murugesan Karthik , Subramaniam Usha
Published: March 2020

There has been increasing interest in the development of Polymer Electrolyte Membrane Fuel Cells (PEMFCs) in recent years as they are the most promising clean energy source for applications in industrial, automotive, portable, and stationary devices. In the present study, characterization of a semi-empirical polymer electrolyte membrane fuel cell model for a test bench of a 5 kW Ballard fuel cell system using a Nafion 117 membrane is performed for the effect of water dynamics on its electrical behavior as it is viewed as a serious issue by fuel cell researchers. The model performance is evaluated for its static and dynamic behavior through the experimental results obtained from a 5 kW Ballard fuel cell stack system to investigate the internal water phenomena of the membrane. The findings of the investigation indicate that the performance of PEMFCs can be significantly improved by maintaining the membrane water content, H2O/SO3−H+, to its optimal value. Thus, the developed model serves as a benchmark tool for the scientific and industrial community to optimize and evaluate the structural design of the PEMFC system for its scale up in terms of its water dynamics.
J-PARC H− ion source and space-charge neutralized LEBT for 100-mA high energy and high duty factor LINACs
Authors: Ueno Akira
Published: March 2020

In July 2019, a design beam of 8.3 × 1013 protons/pulse, whose 25 Hz operation produced the design beam power of 1 MW, was accelerated for 10.5 h by using the J-PARC 3 GeV rapid cycling synchrotron. During the operation, a J-PARC H− ion source and a 400 MeV linear accelerator (LINAC) were operated with the design beam duty factor (BDF) of 1.25% (0.5 ms × 25 Hz) and ejected beam intensities of 58 mA and 50 mA, respectively. Furthermore, as expected from the transverse emittances measured in an H− ion source test-stand, they were successfully operated with the BDF of 1.5% (0.6 ms × 25 Hz) and ejected beam intensities of 72 mA and 60 mA, respectively. In the operation, the beam pulse accelerated by the J-PARC radio-frequency quadrupole LINAC (RFQ) had a rapid rise-time of about 10 µs and an excellent flatness with a slow variation of ±0.2%. A flat beam pulse was produced by the predicted 100% space-charge neutralization (SCN) in the upstream half of the J-PARC low-energy beam transport (LEBT) with a vacuum pressure of 3.6 × 10−4 Pa and the unpredicted high and almost constant SCN of about 69% in the downstream half of the LEBT with a vacuum pressure of 2.8 × 10−5 Pa. The rapid rise-time was produced by the preformed 100% SCN with a preceding 100 µs 40 keV beam, which was not accelerated by the RFQ due to the low energy outside the RFQ acceptance. In the test-stand operated with the terminal voltage of 62 kV and BDF of 5% (1 ms × 50 Hz), the transverse emittances of a 100-mA beam were also measured to be suitable for the RFQs of high energy LINACs. A 100-mA high energy and high duty factor LINAC could be realized with this source since the transverse emittances were further improved by about 8% with the shortest beam extractor in the test-stand.
Temperature dependent optical properties of LaCoO3/SrTiO3 thin film studied by spectroscopic ellipsometry
Authors: Chen Qiao , Wang Xiangqi , Zhang Min , Xu Zilong , Gong Junbo , Rahman Azizur , Fan Lele , Dai Rucheng , Wang Zhongping , Zhang Zengming
Published: March 2020

We report the spectroscopy ellipsometry study for LaCoO3 epitaxy thin films grown on different SrTiO3 substrates [LCO/STO(001) and LCO/STO(111)]. Reciprocal space mapping measurements show that the as-prepared LCO/STO films are fully strained at the interface. The optical constants (the refractive index and the extinction coefficient) of LCO films from 300 K to 800 K are obtained based on the ellipsometry measurements. The optical absorption at the near-infrared region increases with heating and sharply enhances around 500 K due to the occurrence of insulator–metal transition. The observed isosbestic point reveals the evolution of the band structure along with the insulator–metal transition. The red shift of the isosbestic point from the (001) sample to the (111) sample indicates the important role interfacial strain plays in affecting the spin states. We also provide the optical conductivity and the relative effective number of interband transition electrons for different energy regions.
Modulation of ionospheric outflow ions by EMIC waves in the dayside outer magnetosphere
Authors: Shi Chen , Zhao Jinsong , Huang Chaoyan , Wang Tieyan , Dunlop Malcolm W.
Published: March 2020

Cold ions of the ionospheric origin mainly contribute to the ion population in the Earth's magnetosphere. These cold ions can be modulated by Pc5 ultralow frequency waves or wake electric fields in the dayside outer magnetosphere, through which their energy can increase to hundreds of eV. Using measurements of Magnetospheric Multiscale mission, this paper reports a new finding of the cold ion modulation process, occurring at a timescale of several seconds. This modulation is identified to be mainly controlled by large-amplitude electromagnetic ion cyclotron (EMIC) waves through the wave-induced electric field drift. This study also gives distinct observational features in the cold ion modulation processes associated with EMIC waves and wake electric fields.
Determination of doping concentration of heavily doped silicon wafers using photon reabsorption in photocarrier radiometry
Authors: Wang Qian , Liu Weiguo , Gong Lei , Wang Liguo , Li Yaqing
Published: March 2020

A contactless and non-destructive method for the determination of the doping concentration of heavily doped silicon wafers is proposed. The method is based on a comparison between photocarrier radiometry signals acquired from different surfaces of samples and a comprehensive mathematical model by exploiting photon reabsorption in photocarrier radiometry measurements. With the proposed mathematical model, the influence of experimental and sample parameters on the measurement of the doping concentration is analyzed in detail. The uncertainties and limitations of the method are also discussed. Furthermore, an experimental configuration is proposed.
Temperature estimation in a spatially inhomogeneous flame by diode laser absorption spectroscopy
Authors: Liger V.V. , Mironenko V.R. , Kuritsyn Yu.A. , Bolshov M.A.
Published: March 2020

A two-temperature (2T) model is proposed for estimating the temperature of a spatially inhomogeneous hot zone using single-beam diode laser absorption spectrometry. The proposed algorithm is based on fitting experimental absorption spectra by a linear combination of two database-simulated single-temperature spectra with different temperatures. The model efficiency is experimentally demonstrated when determining the temperature in different flame zones of a Wolfgard – Parker slot burner. The proposed 2T algorithm is used to find the maximum and minimum temperatures in different flame sections, which are compared with local temperatures in the same flame zones measured by the method of coherent anti-Stokes Raman scattering (CARS). It is shown that the maximum temperatures determined by the proposed 2T algorithm are in good agreement with CARS data in flame zones where high-temperature regions prevail. A good agreement between the minimum temperatures obtained by these two methods is also observed for predominantly cold zones.
Quantum dot polarisation converter in an optomechanical cavity
Authors: Tsukanov A.V. , Kateev I.Yu.
Published: March 2020

We propose a scheme of a quantum photon polarisation converter, which is based on controlled electron – photon – phonon transitions in a hybrid semiconductor nanostructure. This structure consists of a GaAs/InAs quantum dot (QD) that has a parallelepiped shape and contains a single electron, and an optomechanical microcavity (MC) based on a photonic crystal (PC) that supports two orthogonally polarised photonic modes and one mechanical (phonon) mode. Within the framework of the microscopic theory, the QD and MC performance characteristics are found. Populations of states of the system as functions of time and its parameters are calculated. The principal possibility of photon polarisation conversion using transitions in a five-level resonance scheme for coherent (single-photon) and steady-state (subphoton) regimes is shown. The MC optical and mechanical spectra are simulated, and the PC structure parameters are selected to ensure the efficient operation of the converter.
Nanodiamonds with SiV colour centres for quantum technologies
Authors: Zeleneev A.I. , Bolshedvorskii S.V. , Soshenko V.V. , Rubinas O.R. , Garanina A.S. , Lyapin S.G. , Agafonov V.N. , Uzbekov R.E. , Kudryavtsev O.S. , Sorokin V.N. , Smolyaninov A.N. , Davydov V.A. , Akimov A.V.
Published: March 2020

Properties of silicon-vacancy (SiV) colour centres in ultra-nanosize diamonds are studied. Nanodiamonds are obtained at a high temperature and pressure, which induced transformations in mixtures of organic and hetero-organic compounds without metal-catalysts. The size distribution of grown nanodiamonds is determined by the methods of transmission electron microscopy and atomic-force microscopy, as well as by using the model of phonon spatial localisation. In addition, Raman spectra of various nanodiamonds and luminescence properties of SiV-centres are investigated.
457-nm radiation source based on a diode laser for precision spectroscopy of magnesium atoms
Authors: Goncharov A.N. , Baraulya V.I. , Bonert A.E. , Tropnikov M.A.
Published: March 2020

We report on the development of a highly stable source of 457-nm radiation based on a diode laser and a tapered amplifier operating in a double-pass scheme. The diode laser frequency was stabilised by a high-Q reference Fabry – Perot interferometer and doubled in a PPSLT nonlinear crystal placed in an enhancement cavity. At a maximum output power of 200 mW at a wavelength of 457 nm, the laser linewidth was less than 5 kHz. The radiation source operation was demonstrated in experiments on precision spectroscopy of cold magnesium atoms in a magneto-optical trap.
Three-body Förster resonance of a new type in Rydberg atoms
Authors: Cheinet P. , Pham K.-L , Pillet P. , Beterov I.I. , Ashkarin I.N. , Tretyakov D.B. , Yakshina E.A. , Entin V.M. , Ryabtsev I.I.
Published: March 2020

The three-body Förster resonances 3 × nP3/2(|M|) →nS1/2 + (n + 1)S1/2 + nP3/2(|M*|), controlled by a constant electric field, were realised earlier by the authors in an ensemble of several cold Rydberg Rb atoms. One of the drawbacks of such resonances for potential application in three-qubit quantum gates is the proximity of the two-body Förster resonance 2 × nP3/2 → nS1/2 + (n + 1)S1/2, as well as the possibility of their implementation only for states with values of the principal quantum numbers n ⩽38. A three-body resonance of a new type, 3 × nP3/2 → nS1/2 + (n + 1)S1/2 + nP1/2, which can be realised for arbitrary n, is proposed and analysed. Its specific feature is also that the third atom transits into a state with a different total angular momentum J = 1/2, which has no Stark structure, so that the two-body resonance is completely absent. Numerical calculations showed that for not too strong interaction, it is possible to observe coherent three-body oscillations of the populations of collective states, which is of interest for developing new schemes of three-qubit quantum gates controlled by an electric field.
Frequency transfer via an ultra-stable free-space link
Authors: Kudeyarov K.S. , Kryuchkov D.S. , Vishnyakova G.A. , Zhadnov N.O. , Khabarova K.Yu. , Kolachevsky N.N.
Published: March 2020

An optical frequency transfer at a wavelength of 1542 nm via an ultra-stable 5-m free-space link with active compensation of the phase noise caused by atmospheric fluctuations is demonstrated. The link-induced phase noise and its contribution to the frequency transfer instability are investigated. It is shown that, with the phase compensation system switched on, the link contribution to the relative transfer instability in terms of Allan deviation reaches 1.7 × 10−19 for a 5000-s averaging time.
Degradation of the contrast of a short light pulse in a CPA system
Authors: Masalov A.V. , Chvykov V.V.
Published: March 2020

We have calculated the effect of four-wave mixing of the main radiation pulse with the background radiation components on the value of the output radiation contrast in a chirped pulse amplification system of petawatt laser facilities. Formulae are presented that make it possible to quantify the contributions of two mechanisms, i.e. Kerr nonlinearity of the refractive index of the amplifying medium and gain saturation. For typical values of the nonlinear refractive index, both contributions are comparable. The possibility of mutual quenching of nonlinear contributions is noted. The influence of spectral filtering of radiation on the output pulse contrast is considered.
Concise report: Teenage sexting on the rise? Results of a cohort study using a weighted sample of adolescents
Authors: Van Ouytsel Joris , Walrave Michel , De Marez Lieven , Van Damme Kristin , De Wolf Ralf , Baccarne Bastiaan , Vanhaelewyn Bart , Ponnet Koen
Published: March 2020

Background
The vast differences in sampling techniques, cultural contexts between international studies, the differences in age groups of the samples and various definitions used to measure sexting make it hard to compare how sexting behaviour has evolved over the past years. This exploratory study aims to address this critical gap in the research by using two datasets of a biennial study on adolescents’ media use. The first aim of this study is to compare the sexting prevalence and correlates (i.e. age, gender and smartphone ownership) of youth in 2015 and 2017. The second aim is to investigate the risk mitigation behaviours of youth who engage in sexting and to assess how their behaviours differ between the two time points. Methods: The data for cohort 1 were collected in October and November 2015 and comprise of 2663 students from 11 secondary schools in the Dutch-speaking community of Belgium. For the second cohort, the data were collected in October and November 2017 and comprise of 2681 students from 10 secondary schools. A weighing factor was implemented on the dataset. Results: The results show sexting behaviour has significantly increased between cohorts, with 8.3% of the respondents having sent a sext in the first cohort, compared with 12.1% in the second cohort. The sexting prevalence rates also significantly increased between cohorts when taking into account students who owned a smartphone. Furthermore, engagement in sexting was associated with being older, and no gender differences were found. In the second cohort, 36.8% of youth who had sent a sext were identifiable in those images. There were no differences between cohorts. Conclusion: The results indicate that other factors next to smartphone ownership may be associated with an increase in sexting prevalence. The findings also highlight the need for the development of age-appropriate sexting educational materials.
Provider attitudes to the empiric treatment of asymptomatic contacts of gonorrhoea
Authors: Low Sheina , Varma Rick , McIver Ruthy , Vickers Tobias , McNulty Anna
Published: March 2020

Background
In the current era of antimicrobial stewardship, the availability of highly sensitive assays and faster turnaround times, the practice of empiric treatment of asymptomatic contacts of gonorrhoea needs review. The views of clinicians in a range of settings across Australia and clinic costs associated with a change of practice was examined. Methods: An online anonymous survey for nurses and doctors working in public sexual health clinics and general practices in urban, regional and rural Australia was developed. Information on the relative importance of a range of factors influencing delivery of empiric treatment was collected. Participants were asked whether current guidelines should change. Results: Surveys were distributed to 468 healthcare providers and 188 (40.2%) fully completed the survey. Most of the participants worked in public practice (84.9%) and 86 (43.2%) were doctors. Factors influencing provision of empiric treatment were: if the patient was unable to return (95.9%) or may not return (95.3%); risk of transmission to others (93.3%); likelihood of infection (88.6%); and patient request (82.9%). Respondents were evenly split as to whether current guidelines should change, with providers in private practice being less likely to support guideline change (P = 0.03). The model of empiric treatment of all asymptomatic sexual contacts was 34% more expensive than a model of testing and treatment of those with a positive result. Conclusion: Currently, the majority of clinicians provide empiric treatment for asymptomatic contacts in Australia. There was significant support for a change in guidelines with specific scenarios requiring individualised responses.
Contextual and behavioural risk factors for sexually transmissible infections in young Aboriginal people in central Australia: a qualitative study
Authors: Watson Colin , Smith Kirsty , Latif Ahmed , Armstrong Wendy , Ward James , Guy Rebecca , Senior Kate
Published: March 2020

Rates of sexually transmissible infections (STIs) in remote central Australian Aboriginal communities have been persistently high for over two decades, yet risk factors for STIs in these communities are not well understood. This qualitative study explored behavioural and contextual risk factors for STIs in young Aboriginal people in central Australia. The study identified that casual relationships between young people are common and that there is a strong association between travel, alcohol and casual sex, highlighting the ongoing need for comprehensive sexual health programs that are tailored to the specific social, cultural and interpersonal circumstances of young people in this setting.
Engineering an enhanced voltage-sensing phosphatase
Authors: Kawanabe Akira , Mizutani Natsuki , Polat Onur K. , Yonezawa Tomoko , Kawai Takafumi , Mori Masayuki X. , Okamura Yasushi
Published: March 2020

Voltage-sensing phosphatases (VSP) consist of a membrane-spanning voltage sensor domain and a cytoplasmic region that has enzymatic activity toward phosphoinositides (PIs). VSP enzyme activity is regulated by membrane potential, and its activation leads to rapid and reversible alteration of cellular PIP levels. These properties enable VSPs to be used as a tool for studying the effects of phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) binding to ion channels and transporters. For example, by applying simple changes in the membrane potential, Danio rerio VSP (Dr-VSP) has been used effectively to manipulate PI(4,5)P2 in mammalian cells with few, if any, side effects. In the present study, we report an enhanced version of Dr-VSP as an improved molecular tool for depleting PI(4,5)P2 from cultured mammalian cells. We modified Dr-VSP in two ways. Its voltage-dependent phosphatase activity was enhanced by introducing an aromatic residue at the position of Leu-223 within a membrane-interacting region of the phosphatase domain called the hydrophobic spine. In addition, selective plasma membrane targeting of Dr-VSP was facilitated by fusion with the N-terminal region of Ciona intestinalis VSP. This modified Dr-VSP (CiDr-VSPmChe L223F, or what we call eVSP) induced more drastic voltage-evoked changes in PI(4,5)P2 levels, using the activities of Kir2.1, KCNQ2/3, and TRPC6 channels as functional readouts. eVSP is thus an improved molecular tool for evaluating the PI(4,5)P2 sensitivity of ion channels in living cells.
High-Efficiency Broadband Near-Infrared Single-Photon Frequency Upconversion and Detection*
Authors: Ma Jian-Hui , Hu Hui-Qin , Chen Yu , Xu Guang-Jian , Pan Hai-Feng , Wu E
Published: March 2020

We propose and demonstrate a high efficiency broadband near infrared single-photon upconversion and detection with a broadband pump laser based on sum frequency conversion in the PPLN crystal. By using a pump laser centered at 1040 nm with a spectral bandwidth of 10 nm, the signal single-photons centered at 1562 nm with a broadband bandwidth up to 7.2 nm are frequency-converted from the near infrared to the visible regime. A maximum conversion efficiency of 18.8% is achieved, while the background noise is measured to be only 1.2 × 10−3 counts/pulse. The corresponding spectral linewidth of the upconverted photons is 0.2 nm. This scheme of broadband infrared single-photon upconversion and detection provides potential solutions in infrared laser ranging, broadband infrared imaging and quantum key distribution.
Asymptotical Locking Tomography of High-Dimensional Entanglement*
Authors: Kong Ling-Jun , Liu Rui , Qi Wen-Rong , Wang Zhou-Xiang , Huang Shuang-Yin , Tu Chenghou , Li Yongnan , Wang Hui-Tian
Published: March 2020

High-dimensional (HD) entanglement provides a very promising way of transcending the limitations of the two-dimensional entanglement between qubits for increasing channel capacity in many quantum protocols. In the pursuit of capitalizing on the HD entangled states, one of the central issues is to unambiguously and comprehensively quantify and reconstruct them. The full quantum state tomography is a unique solution, but it is undesirable and even impractical because the measurements increase rapidly in d
4 for a bipartite d-dimensional quantum state. Here we present a very efficient and practical tomography method—asymptotical locking tomography (ALT), which can harvest full information of bipartite d-dimensional entangled states by very few measurements less than 2d
2 only. To showcase the validity and reasonableness of our ALT, we carry out the test with the two-photon spin-orbital angular momentum hyperentangled states in a four-dimensional subspace. Besides high-efficiency and practicality, our ALT is also universal and can be generalized into multipartite HD entanglement and other quantum systems.
Effect of Mean Flow on Acoustic Wave Propagation in a Duct with a Periodic Array of Helmholtz Resonators*
Authors: Liu Jiang-Wei , Yu Dian-Long , Yang Hai-Bin , Shen Hui-Jie , Wen Ji-Hong
Published: March 2020

Sound propagation properties of a duct system with Helmholtz resonators (HRs) are affected by mean flow. Previous studies have tended to focus on the effects of mean flows on acoustic response of a duct system with a finite number of HRs. Employing an empirical impedance model, we present a modified transfer matrix method for studying the effect of mean flow on the complex band structure of an air duct system with an infinite periodic array of HRs. The efficiency of the modified transfer matrix is demonstrated by comparison between an example of transmission response calculation for a finite single HR loaded duct and the finite element simulation result calculated using the COMSOL software. Numerical results are presented to analyze the effect of mean flow on the band structure and transmission loss of the sound wave in the duct system. It is hoped that this study will provide theoretical guidance for acoustic wave propagation of HR silencer in the presence of mean flow.
Growth Control of High-Performance InAs/GaSb Type-II Superlattices via Optimizing the In/Ga Beam-Equivalent Pressure Ratio*
Authors: Su Da-Hong , Xu Yun , Wang Wen-Xin , Song Guo-Feng
Published: March 2020

The performance of type-II superlattice (T2SL) long-wavelength infrared devices is limited by crystalline quality of T2SLs. We optimize the process of growing molecular beam epitaxy deposition T2SL epi-layers on GaSb (100) to improve the material properties. Samples with identical structure but diverse In/Ga beam-equivalent pressure (BEP) ratio are studied by various methods, including high-resolution x-ray diffraction, atomic force microscopy and high-resolution transmission electron microscopy. We find that appropriately increasing the In/Ga BEP ratio contributes to improving the quality of T2SLs, but too large In BEP will much more easily cause a local strain, which can lead to more InSb islands in the InSb interfaces. The InSb islands melt in the InSb interfaces caused by the change of chemical potential of In atoms may result in the “nail” defects covering the whole T2SLs, especially the interfaces of GaSb-on-InAs. When the In/Ga BEP ratio is about 1, the T2SL material possesses a lower full width at half maximum of +1 first-order satellite peak, much smoother surface and excellently larger area uniformity.
Performance Analyses of Planar Schottky Barrier MOSFETs with Dual Silicide Layers at Source/Drain on Bulk Substrates and Material Studies of ErSix/CoSi2/Si Stack Interface*
Authors: Wang Bin , Kong Hao-Yu , Sun Lei
Published: March 2020

A dual silicide layer structure is proposed for Schottky barrier metal-oxide-semiconductor field effect transistors (MOSFETs) on bulk substrates. The source/drain regions are designed to be composed with dual stacked silicide layers, forming different barrier heights to silicon channel. Performance comparisons between the dual barrier structure and the single barrier structure are carried out with numerical simulations. It is found that the dual barrier structure has significant advantages over the single barrier structure because the drive current and leakage current of the dual barrier structure can be modulated. Furthermore, the dual barrier structure’s performance is nearly insensitive to the total silicide thickness, which can relax the fabrication requirements and even make an SOI substrate unnecessary for planar device design. The formation of ErSi
x
/CoSi2 stacked multilayers has been proved by experiments.
Exact solutions of stochastic fractional Korteweg de–Vries equation with conformable derivatives
Authors: Ghany Hossam A. , Hyder Abd-Allah , Zakarya M
Published: March 2020

We deal with the Wick-type stochastic fractional Korteweg de–Vries (KdV) equation with conformable derivatives. With the aid of the Exp-function method, white noise theory, and Hermite transform, we produce a novel set of exact soliton and periodic wave solutions to the fractional KdV equation with conformable derivatives. With the help of inverse Hermite transform, we get stochastic soliton and periodic wave solutions of the Wick-type stochastic fractional KdV equation with conformable derivatives. Eventually, by an application example, we show how the stochastic solutions can be given as Brownian motion functional solutions.