bluuebunny/crossref_metadata_2025 huggingface dataset:
Semiannual Variations in 1,000‐dbar Equatorial Indian Ocean Velocity and Isotherm Displacements from Argo Data
Authors: Zanowski Hannah , Johnson Gregory C.
Published: December 2019

The semiannual Rossby wave in the equatorial Indian Ocean is analyzed using 1,000‐dbar horizontal drift and 3‐D isotherm displacement data from Argo floats. The strong semiannual variations in zonal velocity associated with this wave that have been previously studied are confirmed here, and a more complete picture of the wave is provided with the addition of the 1,000‐dbar meridional velocities and 0‐ to 2,000‐dbar isotherm displacements. At 1,000 dbar, semiannual variations in each field are consistent with Rossby wave physics: Zonal velocity is maximal on the equator, isotherm displacement and meridional velocity extrema are colocated with equatorially symmetric zonal velocity phase reversals near ±2.5° in latitude, and all three fields propagate westward over the year. The latitudinal structure of the meridional velocities in the central and eastern Indian Ocean hints at Rossby wave energy in higher meridional modes than the first, but that signature is not apparent in the isotherm displacements or the zonal velocities. With upward and westward phase propagation and downward and westward energy propagation, isotherm displacement vertical sections confirm the presence of a vertically propagating wave that reaches to at least 2,000 dbar, the deepest extent of the Argo floats.
Quantifying the Impact of Wind‐Current Feedback on Mesoscale Variability in Forced Simulation Experiments of the Agulhas Current Using an Eddy‐Tracking Algorithm
Authors: Braby Laura , Backeberg Björn , Krug Marjolaine , Reason Chris
Published: December 2019

The variability in the source regions of the Agulhas Current is influenced by mesoscale eddies. While existing numerical models are successfully able to capture many aspects of the Agulhas Current, many models are unable to accurately represent the observed eddy dissipation and interaction processes, affecting our understanding of mesoscale variability within the current. In this study, we compare two forced simulation experiments in a regional Hybrid Coordinate Ocean Model (HYCOM), where we change the wind forcing, and using an eddy‐tracking algorithm quantify the local effect of the changed wind stress on source region eddies and their interaction with the northern Agulhas Current. There is an overall reduction in eddy kinetic energy (EKE) over the domain, and the representation of Agulhas Current velocities are improved. This study shows that the contribution of meanders and small eddies to the total EKE of the region is greater than the EKE contribution from tracked mesoscale eddies. Changes in eddy properties resulting from the change in forcing from absolute to relative winds (the wind speed relative to the current speed) have resulted in significantly different mesoscale eddy properties. Finally, the evolution of meanders in the Agulhas Current, including the frequency and dissipation of smaller meanders and Natal Pulse type meanders, was assessed using HYCOM experiments and compared to satellite observations. The simulated frequency of smaller meanders compares more favorably to the observations with the change in wind forcing. However, larger Agulhas Current meanders are now too infrequent in the regional HYCOM.
Submesoscale Features and Turbulent Mixing of an Oblique Anticyclonic Eddy in the Gulf of Alaska Investigated by Marine Seismic Survey Data
Authors: Tang Qunshu , Gulick Sean P. S. , Sun Jie , Sun Longtao , Jing Zhiyou
Published: December 2019

Mesoscale eddies are ubiquitous in the global ocean and can be captured by marine multichannel seismic surveys. In this study, a short‐lived anticyclonic eddy is characterized along the seismic line STEEP11 acquired on 30 September 2008 in northern Gulf of Alaska. Fine‐scale eddy stratification with alternative strong striae and weak layers is regarded as a typical eddy structure of the study region. The eddy center dips along a NW tilted axis of 1.9 ± 0.2° from the horizontal. Submesoscale structures including fronts and filaments coexist around the eddy periphery and dominate ~70% of the eddy volume. The estimated geostrophic current is asymmetric and ageostrophic components must play a significant role in balancing the eddy system. Nonlinearity of the eddy is strong as its rotation speed is much higher than its translation speed. We suggest that Ekman transport is probably responsible for the skewed shape with regards to the asymmetric geostrophic current and asymmetric submesoscale processes. Detailed turbulent diffusivities in and around the eddy are quantified, with an average level of 6.5 × 10−5 m2 s−1. The diapycnal diffusivities show an increasing pattern from the eddy center to the surrounding water. With the pervasive submesoscale processes as the transitional dynamics, a forward cascade of energy could be expected from the mesoscale eddy to the fine‐scale wave‐breaking and turbulence. The irregular vortex structure may reduce the structural stability, facilitate the energy conversion, and accelerate the eddy dissipation.
Magnitude and Phase of Diurnal SST Variations in the ACCESS‐S1 Model During the Suppressed Phase of the MJOs
Authors: Hsu Je‐Yuan , Hendon Harry , Feng Ming , Zhou Xiaobing
Published: December 2019

Diurnal variations of sea surface temperature (DV SST) can affect the heat and moisture fluxes at the air‐sea interface during the suppressed phase of the MJO, thereby conditioning a favorable atmosphere environment for the subsequent MJO active phase. In order to better understand the causes and impacts of DV SST, and the modeling requirements for faithfully simulating these processes, we explore the DV SST and their influences on the air‐sea fluxes during the suppressed phases of three MJO events using a global coupled model, ACCESS‐S1, which has a 1‐m vertical resolution near the ocean surface and coupling frequency of 1 hr. Compared with the MTSAT‐1R satellite SST measurements, ACCESS‐S1 is able to simulate the magnitude of the DV SST reliably but has a phase delay in simulated peak SST of ~3 hr. Imposing an instant vertical mixing in the upper 10 m in ACCESS‐S1 would suppress the DV SST by >1°K and decrease the peak (>30 W m−2) and daily averaged latent heat flux. On the other hand, changing the atmosphere‐ocean coupling frequency within several hours mostly affects the DV SST phase instead of magnitude. Extreme DV SST (>1°K) occurs only when ocean mixing layer depth = 1 m. It implies that vertical resolution of ≤1 m near the sea surface is important for the coupled models to simulate both the magnitude and phase of DV SST accurately and thereby the air‐sea heat fluxes in future model forecast of the MJO.
An Inherent Optical Properties Data Processing System for Achieving Consistent Ocean Color Products From Different Ocean Color Satellites
Authors: Chen Jun , He Xianqiang , Xing Xiaogang , Xing Qianguo , Liu Zhongli , Pan Delu
Published: December 2019

We used field measurements and multimission satellite data to evaluate how well an inherent optical properties (IOPs) data processing system performed at correcting the residual error of the atmospheric correction in satellite remote sensing reflectance (Rrs) and how well the system simultaneously minimized intermission biases between different remote sensing systems. We developed the IOPs data processing system as a semianalytical algorithm called IDAS. Our results show that IDAS generates accurate and consistent IOPs products from two ocean color missions: Sea‐viewing Wide Field‐of‐View Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer Aqua (MODISA). Specifically, with “high‐quality” SeaWiFS and MODISA Rrs data, IDAS provided temporally consistent IOPs products for the oligotrophic open ocean resulting in an annual mean intermission difference of less than 3%, which is significantly lower than what a quasi‐analytical algorithm (QAA) provided. We used IDAS to generate a long time series of bb(555) from the Northwest Atlantic Subtropical Gyre using SeaWiFS (1998 to 2002) and MODISA (2003 to 2017) images. Our results show that the IDAS‐derived annual bb(555) decreased monotonically by 2.81% per decade from 1998 to 2017. Comparing the IDAS‐generated annual trend for bb(555) to the same data processed with the QAA algorithm, we found that the QAA results differed because of impacts of the residual errors of the atmospheric correction and intermission biases. The differences in the annual trends existed despite the same temporal changing patterns of in situ particulate organic carbon existing in the Sargasso Sea and in the satellite chlorophyll‐a concentration in the Northwest Atlantic Subtropical Gyre.
Trading Water for Carbon: Maintaining Photosynthesis at the Cost of Increased Water Loss During High Temperatures in a Temperate Forest
Authors: Griebel Anne , Bennett Lauren T. , Metzen Daniel , Pendall Elise , Lane Patrick N.J. , Arndt Stefan K.
Published: December 2019

Carbon and water fluxes are often assumed to be coupled as a result of stomatal regulation during dry conditions. However, recent observations evidenced increased transpiration rates during isolated heatwaves across a range of eucalypt species under experimental and natural conditions, with inconsistent effects on photosynthesis (ranging from increases to stark declines). To improve the empirical basis for understanding carbon and water fluxes in forests under hotter and drier climates, we measured the water use of dominant trees and ecosystem‐scale carbon and water exchange in a temperate eucalypt forest over three summer seasons. The forest maintained photosynthesis within 16% of baseline rates during hot and dry conditions, despite ~70% reductions in canopy conductance during a 5‐day heatwave. While carbon and water fluxes both decreased by 16% on exceptionally dry days, gross primary productivity only decreased by 5% during the hottest days and increased by 2% during the heatwave. However, evapotranspiration increased by 43% (hottest days) and 74% (heatwave), leading to ~40% variation in traditional water use efficiency (water use efficiency = gross primary productivity/evapotranspiration) across conditions and approximately two‐fold differences between traditional and underlying or intrinsic water use efficiency on the same days. Furthermore, the forest became a net source of carbon following a 137% increase in ecosystem respiration during the heatwave, highlighting that the potential for temperate eucalypt forests to act as net carbon sinks under hotter and drier climates will depend not only on the responses of photosynthesis to higher temperatures and changes in water availability, but also on the concomitant responses of ecosystem respiration.
How to measure the entropy of a mesoscopic system via thermoelectric transport
Authors: Kleeorin Yaakov , Thierschmann Holger , Buhmann Hartmut , Georges Antoine , Molenkamp Laurens W. , Meir Yigal
Published: December 2019

Entropy is a fundamental thermodynamic quantity indicative of the accessible degrees of freedom in a system. While it has been suggested that the entropy of a mesoscopic system can yield nontrivial information on emergence of exotic states, its measurement in such small electron-number system is a daunting task. Here we propose a method to extract the entropy of a Coulomb-blockaded mesoscopic system from transport measurements. We prove analytically and demonstrate numerically the applicability of the method to such a mesoscopic system of arbitrary spectrum and degeneracies. We then apply our procedure to measurements of thermoelectric response of a single quantum dot, and demonstrate how it can be used to deduce the entropy change across Coulomb-blockade valleys, resolving, along the way, a long-standing puzzle of the experimentally observed finite thermoelectric response at the apparent particle-hole symmetric point.
Comparison of Japanese and Indian intestinal microbiota shows diet-dependent interaction between bacteria and fungi
Authors: Pareek Siddhika , Kurakawa Takashi , Das Bhabatosh , Motooka Daisuke , Nakaya Shuuichi , Rongsen-Chandola Temsunaro , Goyal Nidhi , Kayama Hisako , Dodd Dylan , Okumura Ryu , Maeda Yuichi , Fujimoto Kosuke , Nii Takuro , Ogawa Takao , Iida Tetsuya , Bhandari Nita , Kida Toshiyuki , Nakamura Shota , Nair G. Balakrish , Takeda Kiyoshi
Published: December 2019

The bacterial species living in the gut mediate many aspects of biological processes such as nutrition and activation of adaptive immunity. In addition, commensal fungi residing in the intestine also influence host health. Although the interaction of bacterium and fungus has been shown, its precise mechanism during colonization of the human intestine remains largely unknown. Here, we show interaction between bacterial and fungal species for utilization of dietary components driving their efficient growth in the intestine. Next generation sequencing of fecal samples from Japanese and Indian adults revealed differential patterns of bacterial and fungal composition. In particular, Indians, who consume more plant polysaccharides than Japanese, harbored increased numbers of Prevotella and Candida. Candida spp. showed strong growth responses to the plant polysaccharide arabinoxylan in vitro. Furthermore, the culture supernatants of Candida spp. grown with arabinoxylan promoted rapid proliferation of Prevotella copri. Arabinose was identified as a potential growth-inducing factor in the Candida culture supernatants. Candida spp. exhibited a growth response to xylose, but not to arabinose, whereas P. copri proliferated in response to both xylose and arabinose. Candida spp., but not P. copri, colonized the intestine of germ-free mice. However, P. copri successfully colonized mouse intestine already harboring Candida. These findings demonstrate a proof of concept that fungal members of gut microbiota can facilitate a colonization of the intestine by their bacterial counterparts, potentially mediated by a dietary metabolite.
Machine learning guided appraisal and exploration of phase design for high entropy alloys
Authors: Zhou Ziqing , Zhou Yeju , He Quanfeng , Ding Zhaoyi , Li Fucheng , Yang Yong
Published: December 2019

High entropy alloys (HEAs) and compositionally complex alloys (CCAs) have recently attracted great research interest because of their remarkable mechanical and physical properties. Although many useful HEAs or CCAs were reported, the rules of phase design, if there are any, which could guide alloy screening are still an open issue. In this work, we made a critical appraisal of the existing design rules commonly used by the academic community with different machine learning (ML) algorithms. Based on the artificial neural network algorithm, we were able to derive and extract a sensitivity matrix from the ML modeling, which enabled the quantitative assessment of how to tune a design parameter for the formation of a certain phase, such as solid solution, intermetallic, or amorphous phase. Furthermore, we explored the use of an extended set of new design parameters, which had not been considered before, for phase design in HEAs or CCAs with the ML modeling. To verify our ML-guided design rule, we performed various experiments and designed a series of alloys out of the Fe-Cr-Ni-Zr-Cu system. The outcomes of our experiments agree reasonably well with our predictions, which suggests that the ML-based techniques could be a useful tool in the future design of HEAs or CCAs.
Adenovectors encoding RSV-F protein induce durable and mucosal immunity in macaques after two intramuscular administrations
Authors: Salisch N. C. , Izquierdo Gil A. , Czapska-Casey D. N. , Vorthoren L. , Serroyen J. , Tolboom J. , Saeland E. , Schuitemaker H. , Zahn R. C.
Published: December 2019

Respiratory Syncytial Virus (RSV) can cause severe respiratory disease, yet a licensed vaccine is not available. We determined the immunogenicity of two homologous and one heterologous intramuscular prime-boost vaccination regimens using replication-incompetent adenoviral vectors of human serotype 26 and 35 (Ad26 and Ad35), expressing a prototype antigen based on the wild-type fusion (F) protein of RSV strain A2 in adult, RSV-naive cynomolgus macaques. All regimens induced substantial, boostable antibody responses that recognized the F protein in pre- and postfusion conformation, neutralized multiple strains of RSV, and persisted for at least 80 weeks. Vaccination induced durable systemic RSV-F-specific T-cell responses characterized mainly by CD4+ T cells expressing Th1-type cytokines, as well as RSV-F-specific CD4+ and CD8+ T cells, IgG, and IgA in the respiratory tract. Intramuscular immunization with Ad26 and 35 vectors thus is a promising approach for the development of an optimized RSV vaccine expected to induce long-lasting humoral and cellular immune responses that distribute systemically and to mucosal sites.
Slowed Movement Stopping in Parkinson’s Disease and Focal Dystonia is Improved by Standard Treatment
Authors: Choudhury Supriyo , Roy Akash , Mondal Banashree , Singh Ravi , Halder Saptak , Chatterjee Koustav , Baker Mark R. , Kumar Hrishikesh , Baker Stuart N.
Published: December 2019

Patients with Parkinson’s disease and focal dystonia have difficulty in generating and preventing movement. Reaction time (RT) and stop signal reaction time (SSRT) measure the speed to initiate and stop a movement respectively. We developed a portable device to assess RT and SSRT. This incorporated a novel analysis to measure SSRT more efficiently (optimal combination SSRT, ocSSRT). After validation ocSSRT was measured in Parkinson’s disease patients without dyskinesia (PD), cervical dystonia (CD) and writer’s cramp. We also assessed how ocSSRT responded to L-dopa in PD patients and botulinum toxin injections in CD patients. Participants were instructed to release a button following a green LED flash on the device. On 25% of trials, a red LED flashed 5–195 ms after the green LED; participations were instructed to abort the button release on these trials. ocSSRT and RT were significantly prolonged in patients with Parkinson’s disease and focal dystonia (one-way ANOVA p < 0.001). Administration of L-dopa significantly improved ocSSRT and RT in PD patients (p < 0.001). Administration of botulinum toxin significantly improved ocSSRT, but not RT, in CD patients (p < 0.05). ocSSRT is an easily-administered bedside neuro-physiological tool; significantly prolonged ocSSRT is associated with PD and focal dystonia.
Improving the efficacy of selenium fertilizers for wheat biofortification
Authors: Ramkissoon Chandnee , Degryse Fien , da Silva Rodrigo C. , Baird Roslyn , Young Scott D. , Bailey Elizabeth H. , McLaughlin Mike J.
Published: December 2019

Increasing the selenium (Se) concentration of staple crops by fertilization is a valuable pathway to increase Se in the human diet, thus preventing Se deficiency. A pot trial was set up to investigate whether the application of 3.33 µg kg−1 of Se (equivalent to 10 g ha−1) to wheat can be made more efficient by its co-application with macronutrient carriers, either to the soil or to the leaves. In the soil, Se was applied either on its own (selenate only) or as a granular, Se-enriched macronutrient fertilizer supplying nitrogen, phosphorus, potassium or sulfur. Selenium was also applied to leaves at head emergence with, or without, 2% w/v N fertilizers. With grain Se concentrations varying from 0.13–0.84 mg kg−1, soil application of selenate-only was 2–15 times more effective than granular Se-enriched macronutrient fertilizers in raising grain Se concentrations. Co-application of foliar Se with an N carrier doubled the Se concentration in wheat grains compared to the application of foliar Se on its own, the majority of which was in the highly bioavailable selenomethionine fraction. Results from this study demonstrate the possibility of improving the efficacy of Se fertilizers, which could enrich crops with Se without additional application costs in the field.
Bruch’s membrane opening enlargement and its implication on the myopic optic nerve head
Authors: Sung Mi Sun , Heo Min Young , Heo Hwan , Park Sang Woo
Published: December 2019

We examined the association between Bruch’s membrane opening (BMO) area and various ocular parameters and investigated the implication of BMO enlargement on the myopic optic nerve head. One hundred eighty-five myopic eyes were included in this cross-sectional study. Among the included eyes, 53 having axial lengths between 26 and 27 mm were further analyzed to investigate the association between BMO area and various ocular parameters. BMO area, BMO-minimum rim width (BMO-MRW), peripapillary choroidal thickness (pCT), width of β-parapapillary atrophy with and without Bruch’s membrane (PPA+BMand PPA−BM), and presence of lamina cribrosa (LC) defect were evaluated. We found that BMO area tended to increase with increasing axial length, but varied among the highly myopic eyes even though they had similar degrees of myopia. In the subgroup analysis of eyes with axial lengths between 26 and 27 mm, BMO area was highly variable and it significantly correlated with PPA−BMwidth and temporal-inferior, nasal-inferior, and nasal BMO-MRW and pCT. LC defects were more common in myopic eyes with enlarged BMO. A multivariate regression model revealed that higher intraocular pressure, enlarged BMO, and thinner BMO-MRW were associated with LC defects in highly myopic eyes. These findings should be considered when evaluating myopic eyes.
Equilibrium shape of single-layer hexagonal boron nitride islands on iridium
Authors: Petrović Marin , Hoegen Michael Horn-von , Meyer zu Heringdorf Frank-J.
Published: December 2019

Large, high-quality layers of hexagonal boron nitride (hBN) are a prerequisite for further advancement in scientific investigation and technological utilization of this exceptional 2D material. Here we address this demand by investigating chemical vapor deposition synthesis of hBN on an Ir(111) substrate, and focus on the substrate morphology, more specifically mono-atomic steps that are always present on all catalytic surfaces of practical use. From low-energy electron microscopy and atomic force microscopy data, we are able to set up an extended Wulff construction scheme and provide a clear elaboration of different interactions governing the equilibrium shapes of the growing hBN islands that deviate from the idealistic triangular form. Most importantly, intrinsic hBN edge energy and interaction with the iridium step edges are examined separately, revealing in such way the importance of substrate step morphology for the island structure and the overall quality of 2D materials.
The driver of dengue fever incidence in two high-risk areas of China: A comparative study
Authors: Liu Keke , Hou Xiang , Wang Yiguan , Sun Jimin , Xiao Jianpeng , Li Ruiyun , Lu Liang , Xu Lei , Sang Shaowei , Hu Jianxiong , Wu Haixia , Song Xiuping , Zhao Ning , Yan Dongming , Li Jing , Liu Xiaobo , Liu Qiyong
Published: December 2019

In China, the knowledge of the underlying causes of heterogeneous distribution pattern of dengue fever in different high-risk areas is limited. A comparative study will help us understand the influencing factors of dengue in different high-risk areas. In the study, we compared the effects of climate, mosquito density and imported cases on dengue fever in two high-risk areas using Generalized Additive Model (GAM), random forests and Structural Equation Model (SEM). GAM analysis identified a similar positive correlation between imported cases, density of Aedes larvae, climate variables and dengue fever occurrence in the studied high-risk areas of both Guangdong and Yunnan provinces. Random forests showed that the most important factors affecting dengue fever occurrence were the number of imported cases, BI and the monthly average minimum temperature in Guangdong province; whereas the imported cases, the monthly average temperature and monthly relative humidity in Yunnan province. We found the rainfall had the indirect effect on dengue fever occurrence in both areas mediated by mosquito density; while the direct effect in high-risk areas of Guangdong was dominated by temperature and no obvious effect in Yunnan province by SEM. In total, climate factors and mosquito density are the key drivers on dengue fever incidence in different high-risk areas of China. These findings could provide scientific evidence for early warning and the scientific control of dengue fever in high-risk areas.
Age- and sex-related ABC transporter expression in pyrethroid-susceptible and –resistant Aedes aegypti
Authors: Rault Leslie C. , Johnson Ellis J. , O’Neal Scott T. , Chen Rui , McComic Sarah E. , Swale Daniel R. , Anderson Troy D.
Published: December 2019

Resistance mechanisms to synthetic insecticides often include point mutations and increased expression of genes encoding detoxification enzymes. Since pyrethroids are the main adulticides used againstAedes aegypti, which vectors pathogens such as Zika virus, understanding resistance to this insecticide class is of significant relevance. We focused on adenosine triphosphate (ATP)-binding cassette (ABC) transporters in the pyrethroid-resistant Puerto Rico (PR) strain ofAe. aegypti. We investigated the expression patterns of six ABC transporters previously characterized as differentially expressed in insecticide-challenged mosquitoes, or increased mRNA expression in pyrethroid-resistantAe. aegypti, by comparing PR to the Rockefeller (Rock) susceptible strain. No constitutive differential expression between strains was detected, but expression differences for these genes was influenced by sex and age, suggesting that their role is independent from resistance in PR. Instead, ABC transporters may be induced after insecticide exposure. Challenging mosquitoes with deltamethrin, with or without ABC transporter modulators, showed that Rock and PR responded differently, but a contribution of ABC transporters to deltamethrin toxicity is suspected. Moreover, the effect of dexamethasone, which enhanced the inhibition of nerve firing by deltamethrin, was observed using aDrosophilacentral nervous system preparation, showing synergy of these two compounds through the potential inhibition of ABC transporters.
Synthesis and characterization of polyethylene glycol-phenol-formaldehyde based polyurethane composite
Authors: Liu Juan , Chen RiQing , Wang ChunPeng , Zhao YongJun , Chu FuXiang
Published: December 2019

A series of phenol-formaldehyde-polyethylene glycol polyether polyols (PF-PEGs) were synthesized through the condensation polymerization and etherification of phenol, formaldehyde, and poly(ethylene glycol) (PEG) under alkaline conditions and subsequently reacted with 1,6-hexamethylene diisocyanate to obtain polyurethane (PU) films using acetone as solvents. The influence of phenol and formaldehyde to PEG mass ratio ((P + F)/PEG) on the hydroxyl number of PF-PEGs and mechanical properties, thermal stabilities, crystallization behaviors, as well as microstructure of polyurethane composite films were studied using chemical analysis, mechanical tests, thermogravimetric analyses (TGA), dynamic mechanical analyses (DMA), X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), respectively. Results demonstrated that PF-PEGs with (P + F)/PEG of 50/50 had the highest hydroxyl number of 323 mg K(OH)/g. The incorporation of phenol and formaldehyde into PEG improved the mechanical properties of polyurethane films, glass transition temperature (Tg), and thermal properties but resulted in the brittleness characteristic of the composite films and low crystallization properties. Moreover, the synthesis mechanism of PF-PEGs polyurethane composite films was revealed, which would provide a theoretical base for the preparation of the rigid polyurethane foams based on phenolic resins.
Longitudinal Analysis of Paraspinal Muscle Cross-Sectional Area During Early Adulthood – A 10-Year Follow-Up MRI Study
Authors: Mäki Teemu , Oura Petteri , Paananen Markus , Niinimäki Jaakko , Karppinen Jaro , Junno Juho-Antti
Published: December 2019

Only a few previous studies have investigated paraspinal musculature (i.e., multifidus (MF), psoas major (PSM), erector spinae (ES)) in longitudinal, population-based settings. This study aimed to evaluate changes in the cross-sectional area (CSA) of the paraspinal muscles between the ages of 20 and 30 years. The study population consisted of a sub-cohort from the Northern Finland Birth Cohort 1986 (n = 298; 156 men, 142 women). Baseline magnetic resonance imaging was performed at a mean age of 21.3 years and follow-up imaging at 30.6 years. The CSA measurements were performed by tracing the paraspinal muscle outlines individually (MF, ES, PM) and all combined (total muscle area (TMA)) at the L4 cranial endplate level. The longitudinal data analysis was performed using generalized estimating equations modelling. The CSA of MF and ES increased during the follow-up among both sexes (men: MF + 5.7%, p < 0.001; ES + 2.7%, p = 0.001; and women: MF + 10.5%, p < 0.001; ES 9.2%, p = 0.001). The CSA of PM decreased among men (PM −4.0%, p < 0.001) but not among women (PM + 0.5%, p = 0.553). TMA increased significantly only among women (men: +0.5%, p = 0.425; women: +6.5%, p < 0.001). The increases in ES and TMA were more distinct among women than men (p < 0.001). Our study demonstrated clear age- and sex-related changes in paraspinal muscle size in early adulthood.
Author Correction: An in vitro assay and artificial intelligence approach to determine rate constants of nanomaterial-cell interactions
Authors: Price Edward , Gesquiere Andre J.
Published: December 2019

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Signature of multilayer growth of 2D layered Bi2Se3 through heteroatom-assisted step-edge barrier reduction
Authors: Kim Yongsam , Lee Geunsik , Li Nannan , Seo Jikeun , Kim Kwang S. , Kim Namdong
Published: December 2019

During growth of two-dimensional (2D) materials, abrupt growth of multilayers is practically unavoidable even in the case of well-controlled growth. In epitaxial growth of a quintuple-layered $${{\rm{Bi}}}_{2}{{\rm{Se}}}_{3}$$Bi2Se3 film, we observe that the multilayer growth pattern deduced from in situ x-ray diffraction implies nontrivial interlayer diffusion process. Here we find that an intriguing diffusion process occurs at step edges where a slowly downward-diffusing Se adatom having a high step-edge barrier interacts with a Bi adatom pre-existing at step edges. The Se–Bi interaction lowers the high step-edge barrier of Se adatoms. This drastic reduction of the overall step-edge barrier and hence increased interlayer diffusion modifies the overall growth significantly. Thus, a step-edge barrier reduction mechanism assisted by hetero adatom–adatom interaction could be fairly general in multilayer growth of 2D heteroatomic materials.
Red fluorescent pyrazoline-BODIPY nanoparticles for ultrafast and long-term bioimaging
Authors: Zhang Yuandong , Zheng Xiaohua , Zhang Liping , Yang Zhiyu , Chen Li , Wang Lei , Liu Shi , Xie Zhigang
Published: December 2019

A kind of self-assembled pyrazoline-BODIPY with red aggregation-induced emission characteristics has been fabricated for ultrafast and long-term bioimaging.
Correction: A folate-conjugated platinum porphyrin complex as a new cancer-targeting photosensitizer for photodynamic therapy
Authors: Yang Mengqian , Deng Jingran , Guo Ding , Zhang Jie , Yang Lixia , Wu Fengshou
Published: December 2019

Correction for ‘A folate-conjugated platinum porphyrin complex as a new cancer-targeting photosensitizer for photodynamic therapy’ by Mengqian Yang et al., Org. Biomol. Chem., 2019, 17, 5367–5374.
Three dimensional coupled reaction–diffusion modeling of calcium and inositol 1,4,5-trisphosphate dynamics in cardiomyocytes
Authors: Singh Nisha , Adlakha Neeru
Published: December 2019

We propose a three-dimensional unsteady-state mathematical model to describe the mechanism of cardiomyocytes.
Retracted Article: CircRNA PVT1 modulates cell metastasis via the miR-181a-5p/NEK7 axis and cisplatin chemoresistance through miR-181a-5p-mediated autophagy in non-small cell lung cancer
Authors: Yan Limin , Bai Minghe , Xu Jinheng , Li Xuemei , Wu Chenpeng , Zhou Yuntao , Yan Jidong , Zhang Zhiyong
Published: December 2019

In the initiation and evolution of human cancers, circular RNAs (circRNAs) act as crucial regulators.
Effects of low oxygen annealing on the photoelectrochemical water splitting properties of α-Fe2O3
Authors: Makimizu Yoichi , Yoo JeongEun , Poornajar Mahshid , Nguyen Nhat Truong , Ahn Hyo-Jin , Hwang Imgon , Kment Stepan , Schmuki Patrik
Published: December 2019

Low oxygen annealing following anodization is a surprisingly effective method of defect engineering and optimizing α-Fe2O3 electrodes for a maximized photoelectrochemical (PEC) water splitting performance.
Graphene–nucleic acid biointerface-engineered biosensors with tunable dynamic range
Authors: Zhao Zhifeng , Yang Hao , Zhao Wenyue , Deng Sha , Zhang Kaixiang , Deng Ruijie , He Qiang , Gao Hong , Li Jinghong
Published: December 2019

Programmed biosensors with tunable quantification range and higher specificity have been constructed by engineering graphene–nucleic acid biointerfaces.
Aqueous alkaline electrolytes for dynamic windows based on reversible metal electrodeposition with improved durability
Authors: Miller Darren D. , Li Judy Y. , Islam Shakirul M. , Jeanetta Joseph F. , Barile Christopher J.
Published: December 2019

Dynamic windows based on reversible bismuth and copper electrodeposition switch between clear and opaque states using alkaline aqueous electrolytes enabled by a chelating ligand.
All-acceptor polymers with noncovalent interactions for efficient ambipolar transistors
Authors: Chen Zhicai , Li Mingguang , Hu Mengxiao , Wang Shuang , Miao Zhagen , Xu Shen , Chen Cailin , Dong Huanli , Huang Wei , Chen Runfeng
Published: December 2019

By invoking intrachain noncovalent interactions (NCIs) in diazine-based mA-wA polymers, high and balanced hole and electron mobilities were achieved.
Smart and efficient opto-electronic dual response material based on two-dimensional perovskite crystal/thin film
Authors: Li Jie , Xu Chang , Zhang Wan-Ying , Shi Ping-Ping , Ye Qiong , Fu Da-Wei
Published: December 2019

Our opto-electronic dual response material, possessing rapid response and high fatigue resistance, could be widely applied to smart electronic devices.
In vitro corrosion behaviour of phenolic coated nickel–titanium surfaces
Authors: Longela Simon , Chatzitakis Athanasios
Published: December 2019

The biocompatibility of implantable nickel–titanium biomaterials relies on the quality of their surfaces. In this study, nickel–titanium surfaces are coated with phenolic thin films of tannic acid and pyrogallol with the purpose of studying their corrosion resistance in physiological environments. Three tests are performed: the open‐circuit potential test, potentiodynamic polarisation and potentiostatic electrochemical impedance spectroscopy. Polarisation measurements are scrutinised in order to gain knowledge concerning the kinetics of the cathodic and anodic reactions, while the open‐circuit potentials and impedance spectroscopy help to study the electrolyte–surficial interactions. It is found that coating nitinol with polyphenols results in the depletion of the native oxide layer and thus a decrease of corrosion resistance. Pyrogallic treated nitinol surfaces (with a corrosion rate of 0.119 mm/year) are half as electrochemically corrosion resistive as tannic acid‐coated substrate. Therefore, it is proposed that tannic treated nitinol would be a better option if implanted on biomaterial surfaces.
Unsymmetrical bistable multimagnetic circuit permanent magnet actuator for high‐voltage circuit breaker application: analysis, design, and dynamic simulation
Authors: Zeng Guanbao , Xiangyu Yang , Yin Huajie , Jing Yiyang , Zhao Shiwei , Cao Jianghua
Published: December 2019

In this study, an unsymmetrical bistable multi‐magnetic circuit permanent magnetic actuator is proposed. The operating principle and mathematical model of the high‐voltage circuit breaker with the proposed machine are analysed. Additionally, the static and dynamic characteristics of the high‐voltage circuit breaker with the presented machine are investigated and evaluated using numerical finite element analysis methods. Furthermore, the influence of the length of the middle gap and the additional coil in the proposed machine are studied. The advantages of the presented machine, such as less magnet volume, low cost, high force density, and short starting time, are discussed. Finally, a prototype is created and tested, followed by the retrieval of the characteristic curves of the holding force to confirm the proposed design.
Analysis and restraining of eddy current damping effect in linear voice coil motor
Authors: Luo Ciyong , Zhao Rui
Published: December 2019

In the case of designing linear voice coil motors (LVCMs), the aluminium tube is usually used to support and fix the windings. Due to the high‐speed linear reciprocating motion, the eddy‐current damping force in aluminium tube has a large effect on the dynamic characteristic of LVCMs and weakens the resultant force. In this study, an LVCM with forward winding is studied. The cause of eddy current damping force in the original structure of the aluminium tube is analysed, and the corresponding mathematic model is established which is verified by finite element method. To restrain the damping effect, three restraining measurements have been discussed. Then a novel structure of aluminium tube with axial slits and ribbed stiffeners is proposed according to the simulation analysis. During the experimentation process, the mover resultant force is replaced with its acceleration. Results show that the mover acceleration of LVCM with stiffened aluminium tube is bigger than that of the initial one. Hence the resultant force of the proposed structure is improved effectively and the new structure has a good inhibition effect on eddy‐current damping effect.
Pedestrian motion recognition via Conv‐VLAD integrated spatial‐temporal‐relational network
Authors: Peng Shiyu , Su Tingli , Jin Xuebo , Kong Jianlei , Bai Yuting
Published: December 2019

Pedestrian motion recognition is one of the important components of an intelligent transportation system. Since commonly used spatial‐temporal features are still not sufficient for mining deep information in frames, this study proposes a three‐stream neural network called a spatial‐temporal‐relational network (STRN), where the static spatial information, dynamic motion and differences between adjunct keyframes are comprehensively considered as features of the video records. In addition, an optimised pooling layer called convolutional vector of locally aggregated descriptors layer (Conv‐VLAD) is employed before the final classification step in each stream to better aggregate the extracted features and reduce the inter‐class differences. To accomplish this, the original video records are required to be processed into RGB images, optical flow images and RGB difference images to deliver the respective information for each stream. After the classification result is obtained from each stream, a decision‐level fusion mechanism is introduced to improve the network's overall accuracy via combining the partial understandings together. Experimental results on two public data sets UCF101 (94.7%) and HMDB51 (69.0%), show that the proposed method achieves significantly improved performance. The results of STRN have far‐reaching significance for the application of deep learning in intelligent transportation systems to ensure pedestrian safety.
New self‐balancing 7‐level inverter with coupled inductors for 1‐φ grid‐connected renewable energy systems with voltage boosting capability
Authors: Phanikumar Chamarthi , Agarwal Vivek , El Moursi Mohamed Shawky
Published: December 2019

In this study, a new self‐balancing 7‐level inverter (SB7LI) topology, suitable for interfacing the low voltage renewables with the power grid, is proposed that uses coupled inductors to generate additional levels in the output voltage. Owing to the presence of a self‐balancing circuit, the voltage across the two‐input DC capacitors is self‐balanced by charging them in series and discharging them in parallel. The self‐balancing feature of the proposed SB7LI also obviates the sensing of input DC capacitors’ voltages. The SB7LI is controlled using a novel multi‐sine wave pulse width modulation strategy. A significant advantage of the proposed SB7LI topology is that it uses fewer power components in comparison with traditional multi‐level inverter topologies, which ensures higher power density and compact circuits. This also improves the overall efficiency of the system and reduces the cost. Further, a modified version of the SB7LI is also presented with a reduced number of power components. An additional advantage of coupled inductors is their filtering action on the output voltage/current, which reduces the overall filter requirements. SB7LI can be easily extended to an n‐level, 3‐φ application. The proposed SB7LI and modified SB7LI are validated through simulations in MATLAB/SIMULINK and hardware experiments on 300 W laboratory prototypes.
Analysis of the sideband current harmonics and vibro‐acoustics in the PMSM with SVPWM
Authors: Qiu Zizhen , Chen Yong , Liu Xu , Kang Yang , Liu Hai
Published: December 2019

To control the high‐frequency acoustic noise of the permanent magnet synchronous machine (PMSM) with the space vector pulse‐width modulation (SVPWM), an investigation into the mechanism of the sideband vibro‐acoustics is presented in this study. Especially, the relationship is developed between the sideband electromagnetic components and the mechanical vibro‐acoustics, which paves the fundamentals to reduce the noise at the sources. Firstly, the analytical derivations of the sideband voltage and current harmonics are expressed, while the magnetic components of permanent magnet and armature reaction are also discussed in different carrier frequency domains. Secondly, the corresponding radial electromagnetic force analysis is established to acquire the pattern of the vibro‐acoustic. Finally, the proposed multi‐physics models are reconstructed by coupling spatial and temporal features, where the amplitudes are also calculated. A 12‐slot10‐pole prototype PMSM is considered as a case study to testify the accuracy of the proposed method, where the corresponding electromagnetic components are calculated and measured under different conditions, together with the vibration and acoustics. This investigation may provide a new route for the acoustics prediction and the precise optimisation of PMSM.
Fault detection and location in medium‐voltage DC microgrids using travelling‐wave reflections
Authors: Saleh Khaled , Hooshyar Ali , El‐Saadany Ehab F.
Published: December 2019

Fast dc fault detection method is required in medium‐voltage dc (MVDC) microgrids to avoid severe damage to the interfacing converters. Ensuring selectivity and sensitivity of the protection system within a few milliseconds is a major challenge. This study proposes a new technique based on fault launched travelling‐waves (TWs) to detect, classify, and locate different dc fault types in MVDC microgrids. Unlike the existing TW‐based protection and fault location methods, the proposed technique utilises the frequency of TW reflections, rather than their arrival time. Moreover, the fault initiated voltage TW is contained within the faulted line by adding smoothing inductors on line terminals, which (i) prevents relays on adjacent lines from detecting the TW and (ii) results in higher reflected TW magnitudes. Therefore, the proposed method's selectivity and sensitivity are enhanced compared to existing methods. Other salient features of the proposed scheme include a moderate sampling frequency of 2 MHz, detection speed of 128 μs, fault location accuracy of ±25 m, no communication requirement, and independence from system configuration. The proposed scheme's performance has been assessed using a ±2.5 kV TN‐S grounded MVDC microgrid under various conditions. The fault location accuracy of the proposed technique is compared to the conventional single‐terminal TW‐based method.
Control and operation of a three‐phase local energy router for prosumers in a smart community
Authors: Roncero‐Clemente Carlos , Vilhena Nuno , Delgado‐Gomes Vasco , Romero‐Cadaval Enrique , Martins João F.
Published: December 2019

From the electrical energy point of view, the smart community (SC) concept is meant to be as a sustainable and environmentally friendly alternative to the classical configuration. The SC includes small‐scale renewable energy sources (RES) and small‐scale energy storage system (ESS). The SC energy management system acts as an aggregator, aiming to assure benefits for community stakeholders. These trends led to the energy routers (ERs) concept. This study proposes and describes the control strategies for these ERs to contribute to the SC goals. The approach of these strategies increases the RES adjustability, contributing to maintain the ESS state of health. The ER is able to operate simultaneously with active and reactive power control, besides compensating SC grid voltage imbalances, and providing ancillary services to the SC. The proposed control strategies are validated by simulations and experiments.
Comprehensive review of a linear electrical generator for ocean wave energy conversion
Authors: Khatri Pooja , Wang Xu
Published: December 2019

Ocean waves are an abundant source of energy. This energy of the ocean can be converted into useful electrical energy using electrical generators. Linear generators have received tremendous attention in energy harvesting technology due to its unique ability to convert the energy without any intermediate converter. The principal objective of this study is to present the various types of linear electrical generators which have been investigated so far for direct drive ocean wave energy conversion and describe the working principle of each type with the difference. In this study, after a brief description of the basic electrical generator, various types of generators, including the linear and flat generators available in the literature are reviewed and discussed based on the design configuration of different types of magnet arrangements. Linear generators have been compared in terms of core type, flux path, the location of PMs, etc. The research gaps have been identified and future research directions have been suggested.
Research on microstructure and mechanical properties of explosively welded stainless steel/commercially pure Ti plate
Authors: Małek Marcin , Wachowski Marcin , Kosturek Robert
Published: December 2019

Surface protection by the application of explosive welding is one of the meaningful methods used in many chemical devices like reactor condensers, heat exchangers, steam turbines and other processing apparatus. Due to the wide range of explosively welded applications, the problem of the useful lifetime of the products obtained by this method becomes important and should be well understood. Process of explosive welding is related to enormous pressure and high detonation velocity, which causes intense energy release in a short time, which favors to produce solid wavy bond featured with high metallurgical quality. Due to strain hardening in the bond zone, significant changes in microstructures and mechanical properties were observed. In this paper, 316L stainless steel explosively welded with commercially pure titanium was investigated to show the correlations and changes between microstructures and mechanical properties before and after annealing. Application of post-weld heat treatment contributes to stress relieving and improves the mechanical properties, which is closely related to microstructure recrystallization and hardness decrease adjacent to joint.