bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular hydrogen in minerals as a clue to interpret ∂D variations in the mantle
Authors: Moine B. N. , Bolfan-Casanova N. , Radu I. B. , Ionov D. A. , Costin G. , Korsakov A. V. , Golovin A. V. , Oleinikov O. B. , Deloule E. , Cottin J. Y.
Published: July 2020

Trace amounts of water dissolved in minerals affect density, viscosity and melting behaviour of the Earth’s mantle and play an important role in global tectonics, magmatism and volatile cycle. Water concentrations and the ratios of hydrogen isotopes in the mantle give insight into these processes, as well as into the origin of terrestrial water. Here we show the presence of molecular H2 in minerals (omphacites) from eclogites from the Kaapvaal and Siberian cratons. These omphacites contain both high amounts of H2 (70 to 460 wt. ppm) and OH. Furthermore, their ∂D values increase with dehydration, suggesting a positive H isotope fractionation factor between minerals and H2–bearing fluid, contrary to what is expected in case of isotopic exchange between minerals and H2O-fluids. The possibility of incorporation of large quantities of H as H2 in nominally anhydrous minerals implies that the storage capacity of H in the mantle may have been underestimated, and sheds new light on H isotope variations in mantle magmas and minerals.
3D genome organization contributes to genome instability at fragile sites
Authors: Sarni Dan , Sasaki Takayo , Irony Tur-Sinai Michal , Miron Karin , Rivera-Mulia Juan Carlos , Magnuson Brian , Ljungman Mats , Gilbert David M. , Kerem Batsheva
Published: July 2020

Common fragile sites (CFSs) are regions susceptible to replication stress and are hotspots for chromosomal instability in cancer. Several features were suggested to underlie CFS instability, however, these features are prevalent across the genome. Therefore, the molecular mechanisms underlying CFS instability remain unclear. Here, we explore the transcriptional profile and DNA replication timing (RT) under mild replication stress in the context of the 3D genome organization. The results reveal a fragility signature, comprised of a TAD boundary overlapping a highly transcribed large gene with APH-induced RT-delay. This signature enables precise mapping of core fragility regions in known CFSs and identification of novel fragile sites. CFS stability may be compromised by incomplete DNA replication and repair in TAD boundaries core fragility regions leading to genomic instability. The identified fragility signature will allow for a more comprehensive mapping of CFSs and pave the way for investigating mechanisms promoting genomic instability in cancer.
Carbon nanotube porin diffusion in mixed composition supported lipid bilayers
Authors: Sullivan Kylee , Zhang Yuliang , Lopez Joseph , Lowe Mary , Noy Aleksandr
Published: July 2020

Carbon nanotube porins (CNTPs), short pieces of carbon nanotubes capable of self-inserting into a lipid bilayer, represent a simplified model of biological membrane channels. We have used high-speed atomic force microscopy (HS-AFM) and all-atom molecular dynamics (MD) simulations to study the behavior of CNTPs in a mixed lipid membrane consisting of DOPC lipid with a variable percentage of DMPC lipid added to it. HS-AFM data reveal that the CNTPs undergo diffusive motion in the bilayer plane. Motion trajectories extracted from the HS-AFM movies indicate that CNTPs exhibit diffusion coefficient values broadly similar to values reported for membrane proteins in supported lipid bilayers. The data also indicate that increasing the percentage of DMPC leads to a marked slowing of CNTP diffusion. MD simulations reveal a CNTP-lipid assembly that diffuses in the membrane and show trends that are consistent with the experimental observations.
Routing space exploration for scalable routing in the quantum Internet
Authors: Gyongyosi Laszlo , Imre Sandor
Published: July 2020

The entangled network structure of the quantum Internet formulates a high complexity routing space that is hard to explore. Scalable routing is a routing method that can determine an optimal routing at particular subnetwork conditions in the quantum Internet to perform a high-performance and low-complexity routing in the entangled structure. Here, we define a method for routing space exploration and scalable routing in the quantum Internet. We prove that scalable routing allows a compact and efficient routing in the entangled networks of the quantum Internet.
Fluctuation relations and fitness landscapes of growing cell populations
Authors: Genthon Arthur , Lacoste David
Published: July 2020

We construct a pathwise formulation of a growing population of cells, based on two different samplings of lineages within the population, namely the forward and backward samplings. We show that a general symmetry relation, called fluctuation relation relates these two samplings, independently of the model used to generate divisions and growth in the cell population. These relations lead to estimators of the population growth rate, which can be very efficient as we demonstrate by an analysis of a set of mother machine data. These fluctuation relations lead to general and important inequalities between the mean number of divisions and the doubling time of the population. We also study the fitness landscape, a concept based on the two samplings mentioned above, which quantifies the correlations between a phenotypic trait of interest and the number of divisions. We obtain explicit results when the trait is the age or the size, for age and size-controlled models.
Polymorphic phase transition in liquid and supercritical carbon dioxide
Authors: Pipich Vitaliy , Schwahn Dietmar
Published: July 2020

We present experiments on molecular density fluctuations in liquid and supercritical (SC) CO2 using small-angle neutron scattering. Thermal density fluctuations in SC-CO2 determine susceptibility and correlation length identifying the Widom line at their maxima. Droplet formation occurs at the gas–liquid line and between 20 and 60 bar above the Widom line, the corresponding borderline identified as the Frenkel line. The droplets start to form spheres of constant radius of ≈ 45 Å and transform into rods and globules at higher pressure. Droplet formation represents a liquid–liquid (polymorphic) phase transition of the same composition but different density, whose difference defines its order parameter. Polymorphism in CO2 is a new observation stimulating interesting discussions on the topics of gas-like to liquid-like transition in SC fluids and polymorphism since CO2 represents a “simple” van der Waals liquid in contrast to water, which is the most widely studied liquid showing polymorphism in its supercooled state.
Evaluating the accuracy of hand models obtained from two 3D scanning techniques
Authors: Yu Fang , Zeng Lei , Pan Ding , Sui Xinlei , Tang Juyu
Published: July 2020

The aim of this study was to identify an efficient approach for 3D imaging of hand. The 3D photographs of hand were taken with Gemini structured-light scanning system (SL scanning) and CT scanning. The 3D photographs, average time of scanning and reconstruction were compared between these two indirect techniques. The reliability, reproducibility and accuracy were evaluated in these two indirect techniques and the direct measurement (DM). Statistical differences in the measurements were assessed by 99% probability, with clinical significance at > 0.5 mm. The Gemini structured-light scanning system established a complete and smooth 3D hand photograph with shorter scanning and reconstruction time. Reproducibility of CT scanning and SL scanning methods was better (P < 0.01, both) than the DM, but did not differ significantly from each other (P = 0.462). Of the 19 (31.58%) measurements obtained, 6 showed significant differences (P < 0.01). Significant differences were observed more often for circumference dimensions (5/9, 55.56%) than for length dimensions (1/10, 10%). Mean absolute error (AE) of the 10 subjects was very low for 3D CT (0.29 ± 0.10 mm) and SL scanning (0.30 ± 0.11 mm). Absolute percentage error (APE) was 4.69 ± 2.33% and 4.88 ± 2.22% for 3D CT and SL scanning, respectively. AE for the PIP circumference between the 3rd finger (0.58 mm) and 4th finger (0.53 mm) scan was > 0.5 mm, indicating significant difference between DM and CT scanning at the level of 99% probability. In this study, the Gemini structured-light scanning system not only successfully established a complete and smooth 3D hand photograph, but also shortened the scanning and reconstruction time. Compared to the DM, measurements obtained using the two indirect techniques did not show any statistically or clinically insignificant difference in the values of the remaining 17 of 19 measurements (89.47%). Therefore, either of the two alternative techniques could be used instead of the direct measurement method.
Low energy irradiation of narrow-range UV-LED prevents osteosarcopenia associated with vitamin D deficiency in senescence-accelerated mouse prone 6
Authors: Makida Kazuya , Nishida Yoshihiro , Morita Daigo , Ochiai Satoshi , Higuchi Yoshitoshi , Seki Taisuke , Ikuta Kunihiro , Ishiguro Naoki
Published: July 2020

Deficiency of vitamin D is an important cause of osteosarcopenia. The purpose of this study is to examine the effects of low energy narrow-range UV-LED on osteosarcopenia in animal models of senescence-accelerated mouse prone 6 (SAMP6). Preliminary experiments specified the minimum irradiance intensity and dose efficacy for vitamin D production (316 nm, 0.16 mW/cm2, 1,000 J/m2). we set a total of 4 groups (n = 8 per group); vitamin D-repletion without UV irradiation (Vit.D+UV−), vitamin D-repletion with UV irradiation (Vit.D+UV +), vitamin D-deficiency without UV irradiation, (Vit.D−UV−), and vitamin D-deficiency with UV irradiation (Vit.D−UV +). Serum levels of 25(OH)D at 28 and 36 weeks of age were increased in Vit.D−UV+ group as compared with Vit.D−UV− group. Trabecular bone mineral density on micro-CT was higher in Vit.D−UV+ group than in Vit.D−UV− group at 36 weeks of age. In the histological assay, fewer osteoclasts were observed in Vit.D−UV+ group than in Vit.D−UV− group. Grip strength and muscle mass were higher in Vit.D−UV+ group than in Vit.D−UV− group at 36 weeks of age. Signs of severe damage induced by UV irradiation was not found in skin histology. Low energy narrow-range UV irradiation may improve osteosarcopenia associated with vitamin D deficiency in SAMP6.
Structure equation model and neural network analyses to predict coronary artery lesions in Kawasaki disease: a single-centre retrospective study
Authors: Azuma Junji , Yamamoto Takehisa , Nitta Motoaki , Hasegawa Yasuhiro , Kijima Eri , Shimotsuji Tsunesuke , Mizoguchi Yoshimi
Published: July 2020

A new method to predict coronary artery lesions (CALs) in Kawasaki disease (KD) was developed using a mean structure equation model (SEM) and neural networks (Nnet). There were 314 admitted children with KD who met at least four of the six diagnostic criteria for KD. We defined CALs as the presence of a maximum z score of ≥ 3.0. The SEM using age, sex, intravenous immunoglobulin resistance, number of steroid pulse therapy sessions, C-reactive protein level, and urinary β2-microglobulin (u-β2MG/Cr) values revealed a perfect fit based on the root mean square error of approximation with an R2 value of 1.000 and the excellent discrimination of CALs with a sample score (SS) of 2.0 for a latent variable. The Nnet analysis enabled us to predict CALs with a sensitivity, specificity and c-index of 73%, 99% and 0.86, respectively. This good and simple statistical model that uses common parameters in clinical medicine is useful in deciding the appropriate therapy to prevent CALs in Japanese KD patients.
Cryogenic sequenced layering for the 3D reconstruction of biological objects
Authors: Nikolenko Vladimir Nikolaevich , Terpilovsky Alexey Anatolyevich , Kuzmin Alexey Leonidovich , Lukashkina Regina Alekseevna , Strizhkov Alexey Evgenievich , Suslov Andrei Vladimirovich , Kochurova Ekaterina Vladimirovna , Gavrushova Liliya Vladimirovna , Sinelnikov Mikhail Yegorovich
Published: July 2020

Three-dimensional (3D) visualization is applied throughout many specialities, prompting an important breakthrough in accessibility and modeling of data. Experimental rendering and computerized reconstruction of objects has influenced many scientific achievements, facilitating one of the greatest advancements in medical education since the first illustrated anatomy book changed specialist training forever. Modern medicine relies on detailed, high quality virtual models for educational, experimental and clinical purposes. Almost all current virtual visualization methods rely on object slicing producing serial sections, which can then be digitalized or analyzed manually. The tendency to computerize serial sections roots from convenience, accessibility, decent visualization quality and automation capabilities. Drawbacks of serial section imaging is tissue damage occurring within each consequent sectioning. To utilize the important aspects of real-life object reconstruction, and maintain integrity of biological structures, we suggest a novel method of low-temperature layering of objects for digitization and computerized virtual reconstruction. Here we show the process of consequent imaging of each novel layer of a biological object, which provides a computer with high quality data for virtual reconstruction and creation of a multidimensional real-life model. Our method prevents tissue deformation and biodegradation due to specific methods used in preparation of the biological object. The resulting images can be applied in surgical training, medical education and numerous scientific fields for realistic reconstruction of biological objects.
Eye alignment changes caused by sustained GDNF treatment of an extraocular muscle in infant non-human primates
Authors: Fleuriet Jérome , Willoughby Christy L. , Kueppers Rachel B. , Mustari Michael J. , McLoon Linda K.
Published: July 2020

The ability of sustained treatment of a single extraocular muscle with glial cell line-derived neurotrophic factor (GDNF) to produce a strabismus in infant non-human primates was tested. Six infant non-human primates received a pellet containing GDNF, releasing 2 µg/day for 90 days, on one medial rectus muscle. Eye alignment was assessed up to 6 months. Five of the six animals showed a slow decrease in eye misalignment from the significant exotropia present at birth, ending with approximately 10° of exotropia. Controls became orthotropic. Misalignment averaged 8° three months after treatment ended. After sustained GDNF treatment, few changes were seen in mean myofiber cross-sectional areas compared to age-matched naïve controls. Neuromuscular junction number was unaltered in the medial rectus muscles, but were significantly reduced in the untreated lateral recti. Neuromuscular junctions on slow fibers became multiply innervated after this sustained GDNF treatment. Pitx2-positive cells significantly decreased in treated and contralateral medial rectus muscles. Our study suggests that balanced GDNF signaling plays a role in normal development and maintenance of orthotropia. Sustained GDNF treatment of one medial rectus muscle resulted in a measurable misalignment largely maintained 3 months after treatment ended. Structural changes suggest mechanisms for producing an imbalance in muscle function.
Nano-scale depth-varying recrystallization of oblique Ar+ sputtered Si(111) layers
Authors: Gupta Divya , Umapathy G. R. , Singhal Rahul , Ojha Sunil , Aggarwal Sanjeev
Published: July 2020

Silicon, the workhorse of semiconductor industry, is being exploited for various functional applications in numerous fields of nanotechnology. In this paper, we report the fabrication of depth controllable amorphous silicon (a-Si) layers under 80 keV Ar+ ion sputtering at off-normal ion incidences of 30°, 40° and 50° and crystallization of these amorphous Si(111) layers under thermal annealing. We find that the irradiated samples were not fully amorphized even for the lowest oblique incidence of 30°. Sputtering at off-normal incidences induces depth controllable surface amorphization in Si(111). Annealing at temperature of 1,073 K is characterized by formation of depth-varying buried amorphous layer due to defect recrystallization and damage recovery. Some remnant tensile stress has been observed for recrystallized samples even for lowest oblique incidence. The correlation of amorphization and stress due to sputtering induced by oblique incidence has been discussed systematically. The possible mechanism of recrystallization is discussed in terms of vacancies produced in sputtering dominated regime and their migration during annealing treatment. Our results reveal that with appropriate selection of oblique ion beam sputtering parameters, depth controllable surface amorphization and recrystallization may be fine-tuned to achieve co-existing amorphous and crystalline phases, playing a crucial role in fabrication of substrates for IC industry.
Effect of generation rate on transient photoconductivity of semi-insulating 4H-SiC
Authors: Suproniuk Marek , Wierzbowski Mariusz , Paziewski Piotr
Published: July 2020

The effect of generation rate on transient photoconductivity of semi-insulating (SI) 4H-SiC is discussed. The rate of generation of electron–hole pairs is dependent on the number of photons incident on the sample material and its absorption and reflection coefficients. The number of photons and their energy is dependent on the radiation power and wavelength of the light source illuminating the material. The results of research, obtained with a specialized simulator, present the influence of changes in the filling of individual defect centres’ levels on changes in conductivity of the test material observed after switching on the photoexcitation. For the purpose of simulations, presented is a versatile model of semiconductor material. It encompasses six point defects that appear in SI 4H-SiC materials the most often. Those defect centres correspond to Z1/2 recombination centre, deep electron and deep hole traps, nitrogen-related shallow donors of two kinds and a boron-related shallow acceptor. The simulation results can be used to design and determine properties of photoconductive switches.
Author Correction: Germline susceptibility variants impact clinical outcome and therapeutic strategies for stage III colorectal cancer
Authors: Lin Peng-Chan , Yeh Yu-Min , Wu Pei-Ying , Hsu Keng-Fu , Chang Jang-Yang , Shen Meng-Ru
Published: July 2020

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Quantum dot to quantum dot Förster resonance energy transfer: engineering materials for visual color change sensing
Authors: Chern Margaret , Toufanian Reyhaneh , Dennis Allison M.
Published: July 2020

Manipulation of quantum dot (QD) properties improves QD–QD energy transfer enabling the concerted design of visual color change-based sensors.
Coordination distortion induced water adsorption in hydrophobic flexible metal–organic frameworks
Authors: Kamakura Yoshinobu , Hikawa Arata , Yoshikawa Hirofumi , Kosaka Wataru , Miyasaka Hitoshi , Tanaka Daisuke
Published: July 2020

The water-adsorption properties of four isostructural hydrophobic metal-organic frameworks are dependent on the metal species, which was revealed to be caused by coordination distortion around the metal ions.
Electropolymerization in a confined nanospace: synthesis of PEDOT nanoparticles in emulsion droplet reactors
Authors: Lee Myoung Won , Kwon Deok-Jin , Park Junmo , Pyun Jae-Chul , Kim Young-Joo , Ahn Hyun S.
Published: July 2020

Size controlled PEDOT nanoparticles were synthesized by confined space electrochemistry inside emulsions.
Protobranching as repulsion-induced attraction: a prototype for geminal stabilization
Authors: Joyce Justin P. , Shores Matthew P. , Rappè Anthony K.
Published: July 2020

The complementarity of overlap-induced exchange repulsion and electron correlative dispersion suggests that each is important to a complete understanding of branched hydrocarbon stability.
High-rate sodium insertion/extraction into silicon oxycarbide-reduced graphene oxide
Authors: Putra Rio Nugraha , Halim Martin , Ali Ghulam , Shaikh Shoyebmohamad F. , Al-Enizi Abdullah M. , Fazal Tanzeela , Jan Iftikhar Faiza , Saqib Ahmad Nauman Shah
Published: July 2020

Silicone oxycarbide (SiOC) is gaining attention as a potential anode material for lithium-ion batteries due to its higher reversible capacity and high-rate capability.
Isomerization-induced enhancement of luminescence in Au28(SR)20 nanoclusters
Authors: Chen Yuxiang , Zhou Meng , Li Qi , Gronlund Harrison , Jin Rongchao
Published: July 2020

Two Au28(SR)20 nanoclusters with an identical core but different shells exhibit a ∼15-fold difference in photoluminescence.
Carbon nanodots revised: the thermal citric acid/urea reaction
Authors: Strauss Volker , Wang Huize , Delacroix Simon , Ledendecker Marc , Wessig Pablo
Published: July 2020

Products of the thermal reaction of citric acid and urea have been identified as a complex mixture of fluorophores and particles.
Chain reactions: molecular mechanisms of RBR ubiquitin ligases
Authors: Cotton Thomas R. , Lechtenberg Bernhard C.
Published: July 2020

Ubiquitination is a fundamental post-translational modification that regulates almost all aspects of cellular signalling and is ultimately catalysed by the action of E3 ubiquitin ligases. The RING-between-RING (RBR) family of E3 ligases encompasses 14 distinct human enzymes that are defined by a unique domain organisation and catalytic mechanism. Detailed characterisation of several RBR ligase family members in the last decade has revealed common structural and mechanistic features. At the same time these studies have highlighted critical differences with respect to autoinhibition, activation and catalysis. Importantly, the majority of RBR E3 ligases remain poorly studied, and thus the extent of diversity within the family remains unknown. In this mini-review we outline the current understanding of the RBR E3 mechanism, structure and regulation with a particular focus on recent findings and developments that will shape the field in coming years.
Speech-Language Pathology Management for Adults With COVID-19 in the Acute Hospital Setting: Initial Recommendations to Guide Clinical Practice
Authors: Namasivayam-MacDonald Ashwini M. , Riquelme Luis F.
Published: July 2020

Purpose

This document outlines initial recommendations for speech-language pathology management of adult patients with COVID-19 in the acute hospital setting.

Method

The authors initially developed these recommendations by adapting those developed for physical therapists working with patients with COVID-19 by Thomas et al. (2020). The recommendations then underwent review by 14 speech-language pathologists and rehabilitation-focused academics representing seven countries (Belgium, Brazil, Canada, Ireland, Japan, New Zealand, the United States). The authors consolidated and reviewed the feedback in order to decide what should be included or modified. Applicability to a global audience was intended throughout the document.

Results

The authors had 100% agreement on the elements of the recommendations that needed to be changed/modified or added. The final document includes recommendations for speech-language pathology workforce planning and preparation, caseload management, service delivery and documentation, as well as recommendations for the selection of appropriate personal protective equipment and augmentative and alternative communication equipment in the acute care hospital setting.

Conclusions

Speech-language pathologists play a critical role in the assessment, management, and treatment of patients with COVID-19. Several important considerations need to be made in order to meet the needs of this unique patient population. As more is learned about the impact of the virus on swallowing and communication, the role of the speech-language pathologist on interdisciplinary care teams will remain paramount.
Tonal Language Speakers Are Better Able to Segregate Competing Speech According to Talker Sex Differences
Authors: Zhang Juan , Wang Xing , Wang Ning-yu , Fu Xin , Gan Tian , Galvin John J. , Willis Shelby , Xu Kevin , Thomas Mathew , Fu Qian-Jie
Published: July 2020

Purpose

The aim of this study was to compare release from masking (RM) between Mandarin-speaking and English-speaking listeners with normal hearing for competing speech when target–masker sex cues, spatial cues, or both were available.

Method

Speech recognition thresholds (SRTs) for competing speech were measured in 21 Mandarin-speaking and 15 English-speaking adults with normal hearing using a modified coordinate response measure task. SRTs were measured for target sentences produced by a male talker in the presence of two masker talkers (different male talkers or female talkers). The target sentence was always presented directly in front of the listener, and the maskers were either colocated with the target or were spatially separated from the target (+90°, −90°). Stimuli were presented via headphones and were virtually spatialized using head-related transfer functions. Three masker conditions were used to measure RM relative to the baseline condition: (a) talker sex cues, (b) spatial cues, or (c) combined talker sex and spatial cues.

Results

The results showed large amounts of RM according to talker sex and/or spatial cues. There was no significant difference in SRTs between Chinese and English listeners for the baseline condition, where no talker sex or spatial cues were available. Furthermore, there was no significant difference in RM between Chinese and English listeners when spatial cues were available. However, RM was significantly larger for Chinese listeners when talker sex cues or combined talker sex and spatial cues were available.

Conclusion

Listeners who speak a tonal language such as Mandarin Chinese may be able to take greater advantage of talker sex cues than listeners who do not speak a tonal language.
The parallelism between galaxy clusters and early-type galaxies
Authors: D’Onofrio M. , Chiosi C. , Sciarratta M. , Marziani P.
Published: July 2020

Context. This is the second work dedicated to the observed parallelism between galaxy clusters (GCs) and early-type galaxies (ETGs). The focus is on the distribution of these systems in the scaling relations (SRs) observed when effective radii, effective surface brightness, total luminosities, and velocity dispersions are mutually correlated.

Aims. Using the data of the Illustris simulation we speculate on the origin of the observed SRs.

Methods. We compare the observational SRs extracted from the database of the WIde-field Nearby Galaxy-cluster Survey with the relevant parameters coming from the Illustris simulations. Then we use the simulated data at different redshift to infer the evolution of the SRs.

Results. The comparison demonstrate that GCs at z ∼ 0 follow the same log(L)−​log(σ) relation of ETGs and that both in the log(⟨I⟩e)−​log(Re) and log(Re)−​log(M*) planes the distribution of GCs is along the sequence defined by the brightest and massive early-type galaxies (BCGs). The Illustris simulation reproduces the tails of the massive galaxies visible both in the log(⟨I⟩e)−​log(Re) and log(Re)−​log(M*) planes, but fails to give the correct estimate of the effective radii of the dwarf galaxies that appear too large and those of GCs that are too small. The evolution of the SRs up to z = 4 permits to reveal the complex evolutionary paths of galaxies in the SRs and indicate that the line marking the zone of exclusion, visible in the log(⟨I⟩e)−​log(Re) and the log(Re)−​log(M*) planes, is the trend followed by virialized and passively evolving systems.

Conclusions. We speculate that the observed SRs originate from the intersection of the virial theorem and a relation L = L0′σβ where the luminosities depend on the star formation history.
The Obstacle-Avoidance Path Planning for UAV Based on IOCAD
Authors: Zhang Qiqian , Xu Weiwei , Zhang Honghai , Li Han
Published: July 2020

To plan the path for UAV flying in the complex, dense and irregular obstacles environment, this paper proposed an obstacle collision-avoidance detection model and designed an UAV path planning algorithm based on irregular obstacles collision-avoidance detection (IOCAD), which includes irregular obstacles pretreatment method. The proposed method uses the grid method to model the environment. Rough set theory and convexity filling are used to pretreat the obstacles, and the ray method is used to select the available points. The intersection detection and the distance detection are held for the obstacle to the flight path. The objective function minimizes the distance from the obstacle to the flight path to get planned paths. The simulation results show that the proposed method can effectively plan the paths with the constraints of the assumed environment and UAV performances. It is shown that the performance of the proposed method is sensitive to the grid length and safety distance. The optimized values for the grid length and safety distance are 0.5 km and 0.4 km respectively.
A Timeliness-Enhanced Traffic Identification Method in Airborne Network
Authors: Lyu Na , Zhou Jiaxin , Feng Xuan , Chen Kefan , Chen Wu
Published: July 2020

High dynamic topology and limited bandwidth of the airborne network make it difficult to provide reliable information interaction services for diverse combat mission of aviation swarm operations. Therefore, it is necessary to identify the elephant flows in the network in real time to optimize the process of traffic control and improve the performance of airborne network. Aiming at this problem, a timeliness-enhanced traffic identification method based on machine learning Bayesian network model is proposed. Firstly, the data flow training subset is obtained by preprocessing the original traffic dataset, and the sub-classifier is constructed based on Bayesian network model. Then, the multi-window dynamic Bayesian network classifier model is designed to enable the early identification of elephant flow. The simulation results show that compared with the existing elephant flow identification method, the proposed method can effectively improve the timeliness of identification under the condition of ensuring the accuracy of identification.
Underwater Bearing-Only Multitarget Tracking in Dense Clutter Environment Based on PMHT
Authors: Li Xiaohua , Li Ya'an , Lu Xiaofeng , Zhao Chenxu , Yu Jing
Published: July 2020

Underwater bearing-only multitarget tracking in clutter environment is challenging because of the measurement nonlinearity, range unobservability, and data association uncertainty. In terms of the principle of expectation maximization, combining the extended Kalman filter (EKF) and unscented Kalman filter algorithm(UKF), a new bearing-only multi-sensor multitarget tracking via probabilistic multiple hypothesis tracking(PMHT) algorithm is proposed. The PMHT algorithm introduces an association variable to deal with the data association uncertainty problem between the measurements and the targets. Furthermore, the EKF-based PMHT for multi-sensor multitarget system is simplified, which obviate the need to "stack" the synthetic measurements and can reduce the computation cost. The estimation accuracy of the EKF based on PMHT approach and UKF based on PMHT approach in simulation experiments for underwater bearing-only cross-moving targets and closely spaced targets for the case of stationary multiple observations and maneuvering single observation under dense clutter environment is analyzed. The experimental results demonstrate that the present algorithm is very well in a highly clutter environment and its computational load is low, which confirms the effectiveness of the algorithm to the bearing-only multitarget tracking in dense clutter.
Dynamic Modeling and Analysis of Involute Spur Gear Transmission System Considering Friction and Multi-State Meshing Conditions
Authors: Shi Jianfei , Gou Xiangfeng , Zhu Lingyun
Published: July 2020

A dynamic model for an involute spur gear system involving multi-state mesh and friction is formulated to analyze the dynamic response and meshing state property under different lubrication conditions, such as an elastohydrodynamic and mixed lubrications as well as dry friction. The dynamic equations of the system under teeth separation, drive-side and back-side tooth meshes are derived respectively based on the meshing principle of the gear transmission and the force analysis acting on teeth. The effects of the different lubrication schemes on the dynamic meshing force and motion orbit of the system are studied. Results show that the lubrication scheme greatly affects the amplitude of dynamic meshing force. However, the influence of the lubrication scheme on the motion orbit depends mainly on the meshing state. It means that the system motion orbit is largely affected by the lubrication scheme without drive-side and back-side tooth impacts, while the orbit is slightly affected by the lubrication scheme when drive-side and back-side impacts occur. Additionally, the dynamic response and meshing property are investigated with the decrease in load by defining three different Poincaré mappings. The system performs a drive-side meshing state as the load is large. The teeth separation is observed periodically with the decrease in load. While, both teeth separation and back-side mesh are observed under small load, which strengthens the impact vibration between the meshing teeth.
Structural, elastic, vibrational, thermophysical properties and pressure-induced phase transitions of ThN2, Th2N3, and Th3N4: An ab initio investigation
Authors: Sahoo B. D. , Joshi K. D. , Kaushik T. C.
Published: July 2020

The structural, electronic, elastic, lattice dynamical properties and pressure-induced phase transitions in ThN2, Th2N3, and Th3N4 have been investigated through density functional theory based electronic band structure calculations. Our theoretical calculations on ThN2 reveal the monoclinic structure (C2/m space group) at 0 GPa instead of the previously reported cubic (Fm3¯m spatial crystal symmetry) phase [K. O. Obodo and N. Chetty, J. Nucl. Mater. 440, 229 (2013)]. More refined calculations on enthalpy of formation reveal that this ground state C2/m phase of ThN2 transforms to an orthorhombic structure (Pnma symmetry) at a pressure of ∼7 GPa. In agreement with experimental observations, we predict the La2O3-type trigonal structure (P3¯ml symmetry) in Th2N3 at ambient conditions, which is further predicted to transform to an initial monoclinic structure again at ∼62 GPa. Our theoretical results also agree with the experiment regarding the rhombohedral structure (R3¯m symmetry) of Th3N4 revealed at 0 GPa, which, at ∼37 GPa, is predicted to transform to an another rhombohedral structure with reduced space group symmetry of R3¯. The predicted structural phases are further substantiated with the mechanical and dynamical stability criteria in the pressure regime of their structural stability. Furthermore, the electronic band structure calculations at zero pressure suggest that with limited density of states above Fermi energy, ThN2 and Th2N3 exhibit semi-metallic characteristics, whereas a bandgap of ∼1.44 eV in Th3N4 makes it a semiconductor. The semiconducting nature of Th3N4 ceases at a transition pressure of ∼62 GPa.
Development of a multi-color gas puff imaging diagnostic on HL-2A tokamak
Authors: Yuan B. D. , Yu Y. , He R. C. , Yang X. Y. , Xu T. C. , Yuan J. B. , Hong R. J. , Nie L. , Ke R. , Long T. , Wang Z. H. , Xiao C. J. , Xu M. , Li J. Q. , Ye M. Y. , Duan X. R.
Published: July 2020

A Multi-Color (MC) gas puff imaging diagnostic has been developed on HL-2A tokamak. This diagnostic can simultaneously measure two-dimensional (2D, radial, and poloidal) electron density and temperature distributions with a good spatial resolution of 2.5 × 2.5 mm2 and a temporal resolution of about 100 µs at best in edge plasmas. The 2D electron density and temperature distributions are inferred from the ratios of intensities of three different neutral helium emission lines; therefore, it is also referred to as helium beam probe or beam emission spectroscopy on thermal helium. A compact light splitter is used to split the inlet visible emission beam into four channels, and the specific neutral helium lines of the wavelengths λ1 = 587.6 nm, λ2 = 667.8 nm, λ3 = 706.5 nm, and λ4 = 728.1 nm are measured, respectively. This MC diagnostic has been experimentally tested and calibrated on a linear magnetic confinement device Peking University Plasma Test device, and the measured 2D electron density and temperature distributions are compared with the Langmuir probe measurements.
5-GW Tesla-type pulse generator based on a mixed pulse-forming line
Authors: Li Rui , Su Jiancang , Zeng Bo , Yu Binxiong , Cheng Jie , Zhao Liang , Xu Xiudong , Qiu Xudong
Published: July 2020

To shorten the length of the pulse-forming line (PFL) and generate pulses with good flat-top quality, a 5-GW Tesla-type pulse generator based on a mixed PFL is developed in this paper to produce intense electron beams and generate high-power microwaves (HPMs). The mixed PFL is composed of a coaxial PFL and a multistage series annular PFL, which, in turn, consists of 18 coaxial-output capacitor-loaded annular PFL modules in series. The generator can produce quasi-square electrical pulses with a width of 43 ns and a peak power of 5 GW on a matched load. In experiments where it is used to drive a relative backward-wave oscillator to generate HPMs, the results show that the HPM frequency is 16.15 GHz and the power is 1.06 GW with an efficiency of 25% when the voltage of the diode is 620 kV and the beam current is 6.9 kA.
Flexible two-point selection approach for characteristic function-based parameter estimation of stable laws
Authors: Kakinaka Shinji , Umeno Ken
Published: July 2020

Stable distribution is one of the attractive models that well describes fat-tail behaviors and scaling phenomena in various scientific fields. The approach based upon the method of moments yields a simple procedure for estimating stable law parameters with the requirement of using momental points for the characteristic function, but the selection of points is only poorly explained and has not been elaborated. We propose a new characteristic function-based approach by introducing a technique of selecting plausible points, which could bring the method of moments available for practical use. Our method outperforms other state-of-art methods that exhibit a closed-form expression of all four parameters of stable laws. Finally, the applicability of the method is illustrated by using several data of financial assets. Numerical results reveal that our approach is advantageous when modeling empirical data with stable distributions.
Predictors of ED attendance in older patients with chronic disease: a data linkage study
Authors: Xia Ting , Enticott Joanne , Pearce Christopher , Mazza Danielle , Turner Lyle R.
Published: July 2020

Objective Older people represent a large proportion of emergency department (ED) presentations, with multiple comorbidities a strong predictor of frequent attendance. This study examined associations between the general practice management received by older patients with chronic disease and ED attendance. Methods This retrospective study examined linked data from general practice and ED for patients aged ≥65 years who presented to a general practitioner (GP) between 2010 and 2014. Data from the computerised medical records of patients attending 50 general practice clinics in the inner east Melbourne region ere linked with ED attendance data from the same region. Patients with chronic disease were identified and characteristics of ED versus non-ED attendees were compared. Poisson regression was used to explore factors associated with ED usage. Results During the study period, 67 474 patients aged ≥65 years visited a GP, with 63.3% identified as having at least one chronic condition and 21.4% of these having at least one ED presentation. Over 70% of the ED presentations in this group resulted in hospital admissions. The most common diagnoses for ED presentation were cardiovascular disorders, pain and injuries. ED attendance was associated with being aged ≥85 years (incidence rate ratio (IRR) 2.09; 95% confidence interval (CI) 1.96–2.11), higher socioeconomic status (IRR 1.49; 95% CI 1.45–1.53), having a GP management plan (IRR 1.47; 95% CI 1.43–1.52), multimorbidity (IRR 1.53; 95% CI 1.46–1.60), more frequent GP visits (IRR 1.10; 95% CI 1.05–1.15) and having a higher numbers of prescriptions (IRR 1.51; 95% CI 1.44–1.57). Conclusion This study suggests that ED presentation is associated with greater frailty and multimorbidity in patients. Further research is necessary to determine why higher rates of chronic disease management through GP management plans and more frequent visits did not mediate higher rates of presentation and the reasons behind the socioeconomic differences in ED presentation for patients in this age group. What is known about the topic? Increases in the volume and rate of ED presentations by older people will markedly affect emergency and acute hospital care and patient flow as the proportion of older Australians increases. What does this paper add? We used a novel and highly transferable data linkage between data collected from the clinical records of general practice patients and their associated data from ED and hospital settings and examined the relationship between GP management received by older patients with chronic disease and ED attendance. What are the implications for practitioners? Increasing utilisation of GP services may not have an effect on reducing ED attendance, particularly for older patients who may experience poorer overall health.
Qualitative crop condition survey reveals spatiotemporal production patterns and allows early yield prediction
Authors: Beguería Santiago , Maneta Marco P.
Published: July 2020

Significance

We show how subjective information from qualitative crop rating surveys conducted weekly by the USDA can be transformed into a continuous crop condition index that integrates meteorological, agronomic, physiological, technological, and management factors. This index allows comparison of crop conditions between years and locations and provides superior information that enhances yield forecasting models. The proposed methodology can be used to develop better agricultural drought monitoring and early warning systems that can anticipate production anomalies and inform decision making.
T-box transcription factor 3 governs a transcriptional program for the function of the mouse atrioventricular conduction system
Authors: Mohan Rajiv A. , Bosada Fernanda M. , van Weerd Jan H. , van Duijvenboden Karel , Wang Jianan , Mommersteeg Mathilda T. M. , Hooijkaas Ingeborg B. , Wakker Vincent , de Gier-de Vries Corrie , Coronel Ruben , Boink Gerard J. J. , Bakkers Jeroen , Barnett Phil , Boukens Bas J. , Christoffels Vincent M.
Published: July 2020

Significance

Genome-wide association studies have identified common noncoding variants associated with ECG parameters in theTBX3locus, suggesting that a modest change inTBX3/Tbx3expression level affects heart function. We characterized the morphology, physiology, and gene expression profile of the atrioventricular conduction system in aTbx3haploinsufficient mouse model. We identified Tbx3-dependent regulatory DNA elements active in the atrioventricular conduction system and validated the functionality of these elements in vivo. Using genome editing, we deleted a regulatory DNA element from the mouse genome and show it drives expression ofCacna1gin the cardiac conduction system. Our study unveils a Tbx3-dependent gene regulatory network in the AV conduction system that contributes to heart electrophysiology.
High-throughput discovery of phage receptors using transposon insertion sequencing of bacteria
Authors: Kortright Kaitlyn E. , Chan Benjamin K. , Turner Paul E.
Published: July 2020

Significance

Bacteriophages (phages), viruses that infect bacteria, are the most abundant microbes on Earth. Extreme specificity to host species or even strains of bacteria makes phages amenable to particular biotechnical applications. This specificity is partially governed by the surface-expressed structures of bacteria that phages use as cell-binding receptors. However, these receptors remain less-studied in phage biology, because their discovery relies on laborious methods utilizing well-characterized bacteria. Here we present INSeq screens as a rapid, high-throughput tool to identify candidate phage receptors. This method was successful in identifying receptors for previously well-characterized phages T2, T4, T6, and T7 as well as identifying receptors for newly isolated phages R3, U115, EC14, EC35, and 8S.
Clusters of bacterial RNA polymerase are biomolecular condensates that assemble through liquid–liquid phase separation
Authors: Ladouceur Anne-Marie , Parmar Baljyot Singh , Biedzinski Stefan , Wall James , Tope S. Graydon , Cohn David , Kim Albright , Soubry Nicolas , Reyes-Lamothe Rodrigo , Weber Stephanie C.
Published: July 2020

Significance

Bacterial cells are small and were long thought to have little to no internal structure. However, advances in microscopy have revealed that bacteria do indeed contain subcellular compartments. But how these compartments form has remained a mystery. Recent progress in larger, more complex eukaryotic cells has identified a novel mechanism for intracellular organization known as liquid–liquid phase separation. This process causes certain types of molecules to concentrate within distinct compartments inside the cell. Here, we demonstrate that the same process also occurs in bacteria. This work, together with a growing body of literature, suggests that liquid–liquid phase separation is a common mechanism for intracellular organization in both eukaryotic and prokaryotic cells.
Discovery of the world’s highest-dwelling mammal
Authors: Storz Jay F. , Quiroga-Carmona Marcial , Opazo Juan C. , Bowen Thomas , Farson Matthew , Steppan Scott J. , D’Elía Guillermo
Published: July 2020

Environmental limits of animal life are invariably revised when the animals themselves are investigated in their natural habitats. Here we report results of a scientific mountaineering expedition to survey the high-altitude rodent fauna of Volcán Llullaillaco in the Puna de Atacama of northern Chile, an effort motivated by video documentation of mice (genus
Phyllotis
) at a record altitude of 6,205 m. Among numerous trapping records at altitudes of >5,000 m, we captured a specimen of the yellow-rumped leaf-eared mouse (
Phyllotis xanthopygus rupestris
) on the very summit of Llullaillaco at 6,739 m. This summit specimen represents an altitudinal world record for mammals, far surpassing all specimen-based records from the Himalayas and other mountain ranges. This discovery suggests that we may have generally underestimated the altitudinal range limits and physiological tolerances of small mammals simply because the world’s high summits remain relatively unexplored by biologists.