bluuebunny/crossref_metadata_2025 huggingface dataset:
Systematic design study into the influence of rotational speed on the torque density of surface‐mounted permanent magnet machines
Authors: Yu Anshan , Jewell Geraint W.
Published: May 2019

A series of systematic studies are carried out to investigate the influence on torque density and power density on machine speed rating. Several series of permanent magnet machine designs are established using an array of different electrical and thermal design constraints. The paper demonstrates that torque density in permanent magnet machines tends to decrease with speed rating due to complex interplay between electromagnetic and mechanical considerations, e.g. fixed winding current density, fixed split ratio etc. Interesting trends are observed, including cases in which there is an optimum rotational speed in terms of power density, beyond which the power density starts to decrease with increased speed rating.
HD 96446: a long-period binary with a strongly magnetic He-rich primary with β Cephei pulsations
Authors: González J. F. , Briquet M. , Przybilla N. , Nieva M.-F. , De Cat P. , Saesen S. , Hubrig S. , Thoul A. , Pápics P. I. , Palaversa L. , Naef D. , Neveu-Van Malle M. , Järvinen S. , Pollard K. R. , Kilmartin P. , Mowlavi N. , Butler K.
Published: May 2019

Aims. HD 96446 is a magnetic B2p He-strong star that has been reported to be a β Cep pulsator. We present a detailed spectroscopic analysis of this object based on an intensive observational data set obtained in a multisite campaign with the spectrographs CORALIE, FEROS, and HARPS (La Silla); UVES (Paranal); HERCULES (Mt. John Observatory); and GIRAFFE (SAAO).

Methods. Radial velocities were measured by cross-correlations and analysed to detect periodic variations. On the other hand, the mean spectrum was fit with spectral synthesis to derive atmospheric parameters and chemical abundances.

Results. From the analysis of radial velocities, HD 96446 was found to be a spectroscopic binary with a period of 799 days. The stellar companion, which contributes only ∼5% of the total flux, is an A0-type star. A frequency analysis of the radial velocities allowed us to detect two pulsational modes with periods 2.23 h and 2.66 h. The main mode is most probably a low-inclination, dipole mode (l, m) = (1, 0), and the second pulsation mode corresponds to (l, m) = (2, 2) or to a pole-on (l, m) = (3, 2) configuration. In addition to radial velocities, the main pulsation mode is evidenced through small variations in the spectral morphology (temperature variations) and the light flux. The rotation period of 23.4 d, was detected through the variation in line intensities. Chemical abundances are unevenly distributed over the stellar surface, with helium concentrated at the negative magnetic pole and most metals strengthened at lower latitudes. The mean chemical abundance of helium is strongly abnormal, reaching a value of 0.60 (number fraction).
Les organoïdes rénaux
Authors: Steichen Clara , Giraud Sébastien , Hauet Thierry
Published: May 2019

Les organoïdes rénaux dérivés de cellules souches pluripotentes sont devenus une réelle alternative à l’utilisation de modèles in vitro limités ou de modèles animaux contraignants et d’utilisation sensible. La compréhension des mécanismes clés de développement du rein a permis d’établir des protocoles permettant, à partir de cellules souches pluripotentes, d’obtenir de tels organoïdes, qui sont constitués de structures hautement complexes et organisées, contenant plusieurs types cellulaires. Ces organes miniatures permettent des applications majeures : la possibilité de contrôler le génome des iPSC (induced pluripotent stem cell), par sélection de patients atteints de pathologies spécifiques ou par édition de génome, permet d’obtenir in vitro des organoïdes rénaux qui intègrent des mécanismes physiopathologiques, comme le développement de kystes observé dans la polykystose rénale. Ces organoïdes peuvent également être utilisés pour des applications « haut-débit » afin d’accélérer la mise au point de tests de molécules néphrotoxiques ou de composés thérapeutiques. Enfin, les organoïdes rénaux présentent un intérêt majeur dans un contexte de réparation tissulaire, une application qui reste limitée actuellement et pour laquelle de nombreuses barrières restent à franchir.
Influence of Patientʼs Age on the Outcome of Vaginal and Laparoscopic Procedures in Urogynaecology
Authors: Joukhadar Ralf , Radosa Julia , Paulus Viola , Hamza Amr , Solomayer Erich Franz , Herr Daniel , Wöckel Achim , Baum Sascha
Published: May 2019

Introduction In the treatment of prolapse and incontinence, the choice of surgical procedure often depends not only on the clinical findings but also on the age of the patient. Uncertainty exists at present regarding the effect of patient age on treatment outcomes for both vaginal and laparoscopic procedures. The aim of this study is therefore to compare both the anatomical outcome after prolapse surgery and the functional outcome after incontinence surgery in the context of the treatment of stress urinary incontinence in older and younger patients.

Patients/Methods This is a retrospective single-centre study conducted at a university site. Over the study period, a total of 407 women underwent surgery, 278 of whom were < 70 and 129 ≥ 70 years of age. They were assigned to one of three treatment groups (prolapse surgery, incontinence surgery or a combination of both types of surgery) and were then subjected to statistical analysis after assessment of the anatomical and functional outcome after 3 – 6 months.

Results The most common form of prolapse among the 407 evaluated patients was in the anterior and middle compartment, with a higher degree of severity being diagnosed in the older patients. Grade 4 prolapse according to the Baden–Walker system was thus present in the anterior compartment in 15.6 vs. 28.8% (p = 0.033) and in the middle compartment in 5.7 vs. 23.7% (p < 0.001) of cases. Younger women underwent vaginal mesh implantation less frequently and laparoscopic sacropexy more frequently for this overall. The proportion of cases of combined prolapse and incontinence surgery was the same in both groups. Overall, high success rates were observed in both younger and older patients following prolapse and incontinence surgery. These rates were 93.5 vs. 84.8% (p = 0.204) after prolapse surgery and 92.8 vs. 84.2% (p = 0.261) after incontinence surgery. A significant disadvantage for the older patients was the persistence of stress urinary incontinence after prolapse surgery alone (19.6 vs. 50%, p = 0.030) and the rate of occult (de novo) stress urinary incontinence (7.4 vs. 20%, p = 0.030).

Conclusion Our data show that both pelvic organ prolapse and stress urinary incontinence can be treated with surgery with good results in women aged ≥ 70 years. It was thus possible to show for the first time in a large patient population that older women should not be denied appropriate surgery but can be offered the same range of surgical options as younger patients.
Frequency of Secondary Dislocations of Initially non Displaced and Minimally Displaced Fractures of the Lateral Humeral Condyle in Children – Surveillance of a Treatment Algorithm
Authors: Janzen Simeon , von Kalle Thekla , Wirth Thomas , Fernandez Fernandez Francisco
Published: May 2019

Aim of the Study The treatment of undisplaced fractures of the lateral humeral condyle is conservative. However, it is problematic that it is not possible to differentiate between a stable and an unstable, non-displaced fracture. A pragmatic approach is to X-ray the elbow without a cast 5 days after trauma and to compare those images with the initial ones. If there is a central increase of dislocation, then there is an indication of an unstable fracture. The dislocation can also be indicated by a translational movement, which is best observed in the border area. The aim of the study was to retrospectively determine the incidence of secondary dislocations of initially undisplaced and minimally dislocated fractures of the lateral humeral condyle in infants between 2010 and 2015.

Methods We performed a retrospective, non-randomized analysis of 75 children with initially undisplaced and minimally displaced fractures of the lateral humeral condyle between 2010 and 2015. The strategy for the evaluation of a stable and an unstable fracture of the lateral humeral condyle was carried out by means of an X-ray without a cast 5 days after trauma. Further radiological controls were performed after 14 days, 4 weeks and after 10 to 12 weeks in operated children.

Results Seven initially undisplaced and minimally dislocated fractures (9,3%) showed a secondary dislocation 5 days after trauma when a radiological control without a cast was performed. At the control 14 days after trauma there was no further secondary dislocation. The immobilization took place in an upper arm cast for a period of 4 weeks.

Conclusion 90% of all non-dislocated fractures of the lateral humeral condyle can be treated conservatively. It is important to find out which about 10% of children will experience a secondary dislocation safely and effectively. It has been shown that the strategy for the evaluation of a stable and an unstable fracture of the lateral humeral condyle by means of a radiological control after 5 days without a cast can be effective and cost-saving. With a high degree of certainty, the unstable fracture can be detected at the radiological control 5 days after trauma. If, after 5 days, the radiological control reveals unsure finding regarding the dislocation, it is advisable to recheck the fracture in the second radiological control after 14 days.
Complications of Percutaneous Renal Biopsy
Authors: Bakdash Kenaz , Schramm Kristofer M. , Annam Aparna , Brown Matthew , Kondo Kimi , Lindquist Jonathan D.
Published: May 2019

Percutaneous renal biopsy is widely used for diagnosis, prognosis, and management of nephropathies. Complications may arise after renal biopsy, most commonly in the form of bleeding. Efforts should be taken to optimize modifiable risk factors such as hypertension, thrombocytopenia, and coagulopathy prior to the procedure. Unmodifiable risk factors such as poor renal function, gender, and underlying histologic diagnosis may be used to identify high-risk patients. Delayed presentation of bleeding complications is common, and close clinical follow-up is crucial.
Anterior Cord Syndrome after Embolization for Malignant Hemoptysis
Authors: Padgett Max , Abi-Jaoudeh Nadine , Benn Bryan S. , Rahimian Ramin , Nelson Kari
Published: May 2019

Interventional radiology plays an integral role in the management of massive and recurrent submassive hemoptysis. Risks of bronchial artery embolization (BAE) are well described and include spinal ischemia and paralysis, most often related to nontarget embolization of the artery of Adamkiewicz or other large radiculomedullary artery supplying the anterior spinal artery. There is increasing literature regarding spinal infarction following BAE when arterial supply to the spinal cord was not evident. The existence of unrecognized patient comorbidities may further contribute to procedural risks.
Pneumodissection during Percutaneous Renal Ablation Resulting in Air Embolism: Percutaneous Management and a Review of the Literature
Authors: Arif Kamil , Gunn Andrew J.
Published: May 2019

Percutaneous renal ablation is a nephron-sparing approach for selected patients with renal cell carcinoma. Common complications include hemorrhage, injury to the urinary collecting system, and abscess formation. The purpose of this article is to present a case of vascular air embolism as a complication of pneumodissection performed during percutaneous ablation of renal cell carcinoma, discuss its successful percutaneous management, review common complications of renal ablation, and outline steps physicians can take to lessen these complications.
Understanding CancelRx: Results of End-to-End Functional Testing, Proactive Risk Assessment, and Pilot Implementation
Authors: Pitts Samantha I. , Barasch Noah , Maslen Andrew T. , Thomas Bridgette A. , Dorissaint Leonard P. , Decker Krista G. , Kazi Sadaf , Yang Yushi , Chen Allen R.
Published: May 2019

Background CancelRx allows prescribers to send electronic cancellation messages to pharmacies when medications are discontinued. Little is known about its functionality and impact on clinical workflows.

Objectives To understand CancelRx functionality, its potential impact on workflows and medication safety risks, and to develop mitigating strategies for risks introduced by implementation.

Methods We conducted direct observations and semi-structured interviews to develop CancelRx use cases and assessed CancelRx in an end-to-end test environment, proactive risk assessment, and pilot implementation from April 16 to July 15, 2018.

Results E-cancellations were sent upon discontinuation of e-prescriptions written within the electronic health record (EHR), but not other medications (e.g., printed prescriptions) and could be initiated by nonprescribers. In our proactive risk assessment, CancelRx implementation eliminated five of seven failure modes in outpatient prescribing to Johns Hopkins pharmacies, but introduced new risks, including (1) failure to act if an e-cancellation was not sent or was unsuccessful; (2) failure to cancel all prescriptions for a medication; (3) errors in manual matching; and (4) erroneous medication cancellations. We identified potential mitigation strategies for these risks. During pilot implementation, 92.4% (428/463) of e-cancellations had confirmed approval by the receiving pharmacy, while 4.5% (21/463) were denied, and 3.0% (14/463) had no e-cancellation response. Among e-cancellations received by the pilot pharmacy, 1.7% (7/408) required manual matching by pharmacy staff. Based on performance in testing, 73.4% (340/463) of completed e-cancellations would be expected to generate an in-basket message, including 21 (6.2%) denials and 319/340 (93.8%) approvals with a note from the pharmacy.

Conclusion CancelRx is an important functionality with the potential to decrease adverse events due to medication errors. However, changes in implementation in our EHR and pharmacy software and enhancements in the CancelRx standard are needed to maximize safety and usability. Further studies are needed to evaluate the impact of e-cancellation on medication safety.
Plane electromagnetic wave in spatially flat Friedman universe
Authors: Jancewicz Bernard
Published: May 2019

The electromagnetic theory is, to a large extent, metric independent. Before the metric is introduced, it is called premetric electrodynamics. Metric enters the constitutive relation. We consider this relation for the Friedman model of an expanding universe and find that the magnitudes of the field quantities depend on the scale factor. This factor, however, does not enter the permeability and permittivity of the vacuum. A spatially uniform electromagnetic field is obtained for a spatially flat metric. Then, a plane electromagnetic wave is found with a uniform field playing the role of amplitudes. It turns out that the magnitudes of the frequency and the wave covector depend on the scale factor determining the redshift, but the phase velocity of the wave is constant.
Optimization of a laser ion source for 163Ho isotope separation
Authors: Kieck Tom , Biebricher Sebastian , Düllmann Christoph E. , Wendt Klaus
Published: May 2019

To measure the mass of the electron neutrino, the “Electron Capture in Holmium-163” (ECHo) collaboration aims at calorimetrically measuring the spectrum following electron capture in 163Ho. The success of the ECHo experiment depends critically on the radiochemical purity of the 163Ho sample, which is ion-implanted into the calorimeters. For this, a 30 kV high transmission magnetic mass separator equipped with a resonance ionization laser ion source is used. To meet the ECHo requirements, the ion source unit was optimized with respect to its thermal characteristics and material composition by means of the finite element method thermal-electric calculations and chemical equilibrium simulation using the Gibbs energy minimization method. The new setup provides an improved selectivity of laser ionization vs interfering surface ionization of 2700(500) and an overall efficiency of 41(5)% for the ion-implantation process.
High-sensitivity far-forward collective scattering diagnostic on HL-2A tokamak
Authors: Li Y. G. , Li Y. , Zhou Y. , Wang H. X. , Yi J. , Cheng J. , Yao K. , Yu L. M. , Chen W. , Deng Z. C. , Shi Z. B. , Liu Yi. , Yang Q. W.
Published: May 2019

The multichannel formic acid (HCOOH, λ = 432.5 µm) laser interferometer and Faraday-effect polarimeter on HL-2A tokamak have been developed to measure the far-forward collective scattering from electron density fluctuations. The far-forward collective scattering system provides eight channels of line-integrated electron density fluctuations, covering the wave-number range: k⊥ < 1.6 cm−1. With the new diagnostic, the density fluctuations caused by plasma energetic particles and turbulence have been routinely observed in HL-2A experiments.
High-density diffuse optical tomography for imaging human brain function
Authors: Wheelock Muriah D. , Culver Joseph P. , Eggebrecht Adam T.
Published: May 2019

This review describes the unique opportunities and challenges for noninvasive optical mapping of human brain function. Diffuse optical methods offer safe, portable, and radiation free alternatives to traditional technologies like positron emission tomography or functional magnetic resonance imaging (fMRI). Recent developments in high-density diffuse optical tomography (HD-DOT) have demonstrated capabilities for mapping human cortical brain function over an extended field of view with image quality approaching that of fMRI. In this review, we cover fundamental principles of the diffusion of near infrared light in biological tissue. We discuss the challenges involved in the HD-DOT system design and implementation that must be overcome to acquire the signal-to-noise necessary to measure and locate brain function at the depth of the cortex. We discuss strategies for validation of the sensitivity, specificity, and reliability of HD-DOT acquired maps of cortical brain function. We then provide a brief overview of some clinical applications of HD-DOT. Though diffuse optical measurements of neurophysiology have existed for several decades, tremendous opportunity remains to advance optical imaging of brain function to address a crucial niche in basic and clinical neuroscience: that of bedside and minimally constrained high fidelity imaging of brain function.
Merging of defect modes in a superlattice of one-dimensional metamaterials photonic crystals
Authors: Shokri A. A. , Jamshidi R.
Published: May 2019

The optical properties are investigated in a new type of one-dimensional photonic crystal, which consists of two-layer unit cells. The first layer consists of a material with a negative refractive index (NIM) and the other is made of AlxGa1−xAs with a positive refractive index (x is content of Al in GaAs slab). Based on the transfer matrix method (TMM) and the Maxwell’s equation the dependence of photonic bandgaps (PBGs) and omni-directional photonic bandgaps (OPBGs) on the geometrical structure, characteristic of incident light and the content parameter are studied theoretically, in both TE and TM polarization modes. The bandgap in the transmission spectrum originate from the Bragg’s condition in the superlattice, while the existence of the defect layer gives rise to defect modes in the photonic bandgaps. Our results may be useful to better control the position of bandgaps in the optical filters and sensors designing.
Spectral gaps of frustration-free spin systems with boundary
Authors: Lemm Marius , Mozgunov Evgeny
Published: May 2019

In quantum many-body systems, the existence of a spectral gap above the ground state has far-reaching consequences. In this paper, we discuss “finite-size” criteria for having a spectral gap in frustration-free spin systems and their applications. We extend a criterion that was originally developed for periodic systems by Knabe and Gosset-Mozgunov to systems with a boundary. Our finite-size criterion says that if the spectral gaps at linear system size n exceed an explicit threshold of order n−3/2, then the whole system is gapped. The criterion takes into account both “bulk gaps” and “edge gaps” of the finite system in a precise way. The n−3/2 scaling is robust: it holds in 1D and 2D systems on arbitrary lattices and with arbitrary finite-range interactions. One application of our results is to give a rigorous foundation to the folklore that 2D frustration-free models cannot host chiral edge modes (whose finite-size spectral gap would scale like n−1).
Three-dimensional charge transport mapping by two-photon absorption edge transient-current technique in synthetic single-crystalline diamond
Authors: Dorfer C. , Hits D. , Kasmi L. , Kramberger G. , Lucchini M. , Mikuž M. , Wallny R.
Published: May 2019

We demonstrate the application of the two-photon absorption transient current technique to wide bandgap semiconductors. We utilize it to probe charge transport properties of single-crystal Chemical Vapor Deposition (scCVD) diamond. The charge carriers, inside the scCVD diamond sample, are excited by a femtosecond laser through simultaneous absorption of two photons. Due to the nature of two-photon absorption, the generation of charge carriers is confined in space (3-dimensional, 3-D) around the focal point of the laser. Such localized charge injection allows us to probe the charge transport properties of the semiconductor bulk with a fine-grained 3-D resolution. Exploiting spatial confinement of the generated charge, the electrical field of the diamond bulk was mapped at different depths and compared to an X-ray diffraction topograph of the sample. Measurements utilizing this method provide a unique way of exploring spatial variations of charge transport properties in transparent wide-bandgap semiconductors.
Electronic transport of SiC molecular chains in parallel via first-principles calculations
Authors: Mu Yi , Lan Jun-Qing , Zhou Xiao-Lin , Chen Qi-Feng
Published: May 2019

Motivated by the trend of increasing miniaturization and multifunctional implementation, the electronic transport properties of two silicon carbide (SiC) molecular chains in parallel sandwiched between two semi-infinite Au(100)-3 × 6 electrodes are investigated using the density-functional theory and nonequilibrium Green's function formalism. The π-bonding molecular orbitals resulting from the in-phase combination of two px or py atomic orbitals of the C and Si atoms are found to play a key role in the electronic transport, and the possible electron pathways are summarized. Our results show that changing the separation between the two chains in a certain range can produce remarkable differences in transport properties. When the two chains are in small separation (d = 2.884 Å), their strong electrostatic interaction makes a constructive contribution to the electronic transport properties, in which the underlying physical mechanism has been revealed. We also find that d = 5.768 Å is the critical distance both for the transport difference and for the electrostatic interaction in the top-top configuration. Both the conductance (classical Kirchhoff's superposition law) and the current follow the superposition law well in the atomic scale when d = 5.768 Å, much smaller than the critical distance of 15.5 Å from the result of Zhou et al. [Carbon 95, 503 (2015)]. Additionally, the superposition law is more valid for a larger chain spacing (d ≥ 5.768 Å). Our work demonstrates that the realization of the superposition law and the way of increasing current and rectification effect may lay the foundation for the miniaturization exploration and multifunctional implementation of SiC chain related molecular devices.
Smartphone operable centrifugal system (SOCS) for on-site DNA extraction from foodborne bacterial pathogen
Authors: Jeong Soon Woo , Park Yoo Min , Jo Sung Hee , Lee Seok Jae , Kim Yong Tae , Lee Kyoung G.
Published: May 2019

The on-site recovery of nucleic acid from foodborne bacteria is in high demand to further understand on-site molecular diagnosis, which is especially applicable in developing countries. Here, we first proposed a smartphone operable centrifugal system (SOCS) for nucleic acid extraction with the assistance of a low power consumable motor and hydrogel beads. The SOCS consists of a centrifugal motor, 3D-printed cartridge, a nucleic acid collection column, and a smartphone. The SOCS shows excellent DNA extraction performance within 6 min, and it can operate more than 100 times using a smartphone. The purified effluent DNA was accumulated in the nucleic acid collection column. The performance of the SOCS was confirmed by amplifying the recovered DNA from Escherichia coli O157:H7. Moreover, the artificially inoculated food and blood samples also confirmed the performance of SOCS. The proposed SOCS provides an on-site operable nucleic acid separation platform in terms of simplicity, easy usability, cost-effectiveness, and portability in pathogenic point-of-care diagnostics.
The breakdown of the local thermal equilibrium approximation for a polymer chain during packaging
Authors: Kwon Seulki , Lee Seulgi , Cho Hyun Woo , Kim Jeongmin , Kim Jun Soo , Sung Bong June
Published: May 2019

The conformational relaxation of a polymer chain often slows down in various biological and engineering processes. The polymer, then, may stay in nonequilibrium states throughout the process such that one may not invoke the local thermal equilibrium (LTE) approximation, which has been usually employed to describe the kinetics of various processes. In this work, motivated by recent single-molecule experiments on DNA packaging into a viral capsid, we investigate how the nonequilibrium conformations and the LTE approximation would affect the packaging of a polymer chain into small confinement. We employ a simple but generic coarse-grained model and Langevin dynamics simulations to investigate the packaging kinetics. The polymer segments (both inside and outside the confinement) stay away from equilibrium under strong external force. We devise a simulation scheme to invoke the LTE approximation during packaging and find that the relaxation of nonequilibrium conformations plays a critical role in regulating the packaging rate.
Diffusion dynamics of supercooled water modeled with the cage-jump motion and hydrogen-bond rearrangement
Authors: Kikutsuji Takuma , Kim Kang , Matubayasi Nobuyuki
Published: May 2019

The slow dynamics of glass-forming liquids is generally ascribed to the cage jump motion. In the cage jump picture, a molecule remains in a cage formed by neighboring molecules and, after a sufficiently long time, it jumps to escape from the original position by cage breaking. The clarification of the cage jump motion is therefore linked to unraveling the fundamental element of the slow dynamics. Here, we develop a cage jump model for the dynamics of supercooled water. The caged and jumping states of a water molecule are introduced with respect to the hydrogen-bond (H-bond) rearrangement process and describe the motion in supercooled states. It is then demonstrated from the molecular dynamics simulation of the TIP4P/2005 model that the characteristic length and time scales of cage jump motions provide a good description of the self-diffusion constant that is determined in turn from the long-time behavior of the mean square displacement. Our cage jump model thus enables the connection between H-bond dynamics and molecular diffusivity.
Full dimensional quantum mechanical calculations of the reaction probability of the H + NH3 collision based on a mixed Jacobi and Radau description
Authors: Zhang Zhaojun , Gatti Fabien , Zhang Dong H.
Published: May 2019

The collision between hydrogen and ammonia is a benchmark system to study chemical elementary reactions with five atoms. In this work, we present a description of the system based on mixed Jacobi and Radau coordinates combined with the time-dependent wave packet method to study the H + NH3 reaction. The Radau coordinates are used to describe the reactive moiety NH2. A salient feature of this approach is that the present coordinates have a great advantage that a very small number of basis set functions can be used to describe the NH2 group. Potential-optimized discrete variable representation basis is applied for the vibrational coordinates of the reagent NH3. The reaction probabilities for several initial vibrational states are presented in this paper. The role of the different vibrational excitations on the reactivity is thoroughly described.
All-angle Brewster effect observed on a terahertz metasurface
Authors: Wang Chun , Zhu Zhongbo , Cui Wanzhao , Yang Yanbin , Ran Lixin , Ye Dexin
Published: May 2019

In physics, the Brewster effect initially refers to a reflectionless transmission of a transverse-magnetic wave that impinges on an interface separating two different regular media at a particular angle, known as the Brewster angle. Nowadays, people have recognized that the Brewster effect can also be observed under transverse-electric incidences such as in magnetic media. However, all Brewster effects observed so far were associated with a unique incident angle. In this work, we demonstrate a Terahertz metasurface on which the Brewster effect can be observed at all angles of incidence. The underlying physics behind this all-angle Brewster effect is the dispersion engineered at each angle of incidence to strictly match the longitudinal wave impedance on both sides of the surface. Theoretical analysis, full-wave simulation, and experimental results are consistent with each other. The proposed approach is simple but robust and scalable to other frequencies, implying promising applications such as perfect polarizers and space phase shifters.
Isotopic labelling for sensitive detection of nanoparticle uptake and translocation in plants from hydroponic medium and soil
Authors: Nath Jayashree , Dror Ishai , Landa Premysl , Motkova Katerina , Vanek Tomas , Berkowitz Brian
Published: May 2019

Environmental contextBioaccumulation of nanoparticles in plants used for food and feed could be a major exposure pathway to nanoparticles, resulting in ecological and health risks. Isotopic labelling of nanoparticles enables their sensitive tracing in the presence of background elements in complex plant matrices. We investigate nine individual cases of plant–NP interactions and show the role of plants in the uptake and translocation of nanoparticles or their dissolution into metals.
AbstractUnintended releases of nanoparticles (NPs) into agricultural soil have recently raised concerns regarding NP accumulation in plants. In this study, specially synthesised isotopically labelled 107Ag-NPs, 65Cu-NPs and 70ZnO-NPs were exposed to three representative plants (Arabidopsis thaliana, Solanum lycopersicum (tomato) and Phragmites australis (common reed)) in hydroponic cultivation and, separately, to tomato plants cultivated in soil at concentrations of 2mgL−1. Metal concentrations in all samples were analysed by inductively coupled plasma mass spectrometry following acid digestion. The use of isotopically labelled NPs confirmed that elevated levels of metals were from the NP source used for the experiments. Although the highest concentrations of NPs or metals were detected in roots in both hydroponic and soil cultivations, varied levels of translocation to shoots were observed in different plants under hydroponic cultivation. In soil cultivation, where tomato plants were grown to full maturity, low levels of 107Ag (0.38mgkg−1) with respect to controls were recorded in tomato fruits; 70Zn showed the highest level of translocation to tomato stems (2.72mgkg−1) and leaves (13.93mgkg−1). Furthermore, the amounts of NPs retained in the soil (at different depths) after harvesting tomato plants were also determined; the highest concentrations of respective isotopes (1.25mgkg−1 of 107Ag, 0.79mgkg−1 of 65Cu, 4.06mgkg−1 of 70Zn) were found in the top soil layer (~3cm). Analysis of NPs exposed to plants in hydroponic medium indicated that the presence of plants increases the dissolution of NPs. Scanning electron microscopy analysis enabled determination of the location of 107Ag-NPs in the roots of tomato plants grown in soil; these NPs were found to accumulate mainly in the cortical cells.
The stoichiometry of the outer kinetochore is modulated by microtubule-proximal regulatory factors
Authors: Dhatchinamoorthy Karthik , Unruh Jay R. , Lange Jeffrey J. , Levy Michaella , Slaughter Brian D. , Gerton Jennifer L.
Published: May 2019

The kinetochore is a large molecular machine that attaches chromosomes to microtubules and facilitates chromosome segregation. The kinetochore includes submodules that associate with the centromeric DNA and submodules that attach to microtubules. Additional copies of several submodules of the kinetochore are added during anaphase, including the microtubule binding module Ndc80. While the factors governing plasticity are not known, they could include regulation based on microtubule–kinetochore interactions. We report that Fin1 localizes to the microtubule-proximal edge of the kinetochore cluster during anaphase based on single-particle averaging of super-resolution images. Fin1 is required for the assembly of normal levels of Dam1 and Ndc80 submodules. Levels of Ndc80 further depend on the Dam1 microtubule binding complex. Our results suggest the stoichiometry of outer kinetochore submodules is strongly influenced by factors at the kinetochore–microtubule interface such as Fin1 and Dam1, and phosphorylation by cyclin-dependent kinase. Outer kinetochore stoichiometry is remarkably plastic and responsive to microtubule-proximal regulation.
Kota Saito: Getting out and about
Authors: O’Donnell Marie Anne
Published: May 2019

Saito studies the mechanisms that control secretion of collagen from the ER.
Research and Implementation of Key Techniques for Indoor Movement Object Trajectory Prediction
Authors: Zhang Ping , Jiang Qianqian , Zhang Ruilin , Li Bo
Published: May 2019

With the popularity of smart mobile terminals and Wi-Fi signals, people’s demand for indoor location services has also increased. However, in the indoor space, GPS positioning is inaccurate, and the Wi-Fi signal may also have signal instability even no signal in some areas. This paper proposes a prediction method based on improved HMM model combined with historical trajectory clustering. The experimental results on UJIIndoorLoc data set show that the predicting trajectories can greatly improve the real-time performance of location services and the proposed method has great improvement in accuracy and scalability comparing with another model.
Design for Guidance Method of UAV Autonomous Landing on Mobile Platform Based on Prediction of Intersection Points
Authors: Jiang Jun , Qi Guodong , Huang Guoxian
Published: May 2019

The development of the technology for UVAs (Unmanned Aerial Vehicle) autonomous landing on mobile platform is introduced in this article. And the existing problems of UAVs autonomous landing on mobile platforms are also analysed. In order to solve these problems, a guidance method of UAV autonomous landing on mobile platform based on prediction of intersection points is proposed in this paper. In this method, the intersection point of the trajectory of UAV and the trajectory of the mobile platform is predicted based on the speed plan for UAV and the motion state of mobile platform. Then, the UAV will be guided to the intersection point by proportional guidance law. And at each time of the landing of the UAV, the location of the intersection point will be corrected in real time. In order to verify this method, a mathematical simulation experiment was designed. The result of this experiment shows that UAVs are able to land more accurately on the mobile platform with less overload using this method.
Vision-Based Hazard Detection with End-to-end Spatiotemporal Networks for Planetary Landing
Authors: Huang Cheng , Wang Hongmei
Published: May 2019

Hazard detection is the key technique for autonomous landing during a planetary exploration mission. This paper proposed an end-to-end spatiotemporal network to detect all hazards in the image sequences captured by optical camera. The spatial stream processes the colour image sequences and the temporal one learns features from optical flow image sequences. The spatial features and temporal features are fused by the proposed metric fusion method, and then the spatiotemporal features become more discriminative through triplet loss. A hazard map can ultimately be obtained in the testing phase after processing on the full-size image sequences. The evaluation results prove the effectiveness of the proposed network, and the testing results show the feasibility of practical application.
Path Planning of Unmanned Air Vehicles Relay Communication Based on Lowest Power Loss
Authors: Xiao Ruiying , Yang Fan , Dong Zhenghong
Published: May 2019

Unmanned aerial vehicle (UAV) relay communication is an important means to realize long-range wireless communication, where the lowest power loss could prolong the air residence time and increase the duration of the relay communication of UAV. In this paper, we present a UAV relay communication path planning based on the minimum encircling circle algorithm for the UAV working at the lowest power loss. We acquired the minimum radius of UAV relay communication based on for moving platform positions, and then determined the 3D position and flight path of UAV. Compared with the centroid enclosing circle algorithm, our simulation can reduce the signal transmitting power, realize the path planning of UAV relay communication under the lowest power loss.
Research on Influence of Microburst on Ballistic Characteristics of Rockets
Authors: Jianwei Chen , Liangming Wang , Zijie Li
Published: May 2019

In order to study the influence of microburst on the ballistic characteristics of rockets, an engineering model was established by using the vortex ring method based on the basic principle of hydrodynamics and the theory of the exterior ballistic. The wind field model is combined with the six-degree-of-freedom rigid-body ballistic model of rockets. This study examined a kind of empennage-rocket whose flight process was influenced by a microburst. The simulation results show that the microburst model based on the vortex method is simple and the three-dimensional characteristics are good, which can describe the main wind field characteristics of the microburst in a certain extent. Meanwhile, the microburst affects the ballistic characteristics of rockets such as the trajectory, velocity and angular motion. The extent of the effect is concerned with the vertical wind velocity along the central axis and the vortex ring radius of the microburst model.
Study on Properties of Interlayer Short Fiber Reinforced Carbon Fiber/Epoxy Composite Laminates
Authors: Liu Weiwei , Li Weiwei , Ma Chengyan , Wang Shuai
Published: May 2019

In order to improve the interlaminar delamination resistance of the carbon-fiber/epoxy composite laminates, short fibers were applied between layers. The effects of length, density, type of short fiber on mode I fracture toughness(GIC) and mode II fracture toughness (GIIC) were investigated by three-factor and four-level orthogonal test combined with range analysis and scanning electron microscope observation. Finally, parameter optimization and test verification. The results show that the order of factors influencing GIC and GIIC within the selected parameters are: fiber type, fiber density and fiber length. When Kevlar fibers with a length of 11mm and a density of 20g·m-2 were laid between layers, the GIC was 451.4J·m-2, which was 82.2% higher than that of the specimens without short fibers in the layers. Kevlar fibers with a length of 11 mm and a density of 5g·m-2 were layered with a GIIC of 2034.3 J·m-2, which was increased by 240.5% compared with the specimens without short fibers in the interlayer.
Contrasting responses in dissolved organic carbon to extreme climate events from adjacent boreal landscapes in Northern Sweden
Authors: Tiwari Tejshree , Sponseller Ryan A , Laudon Hjalmar
Published: May 2019

The ongoing pressures of climate change, as expressed by the increased intensity, duration, and frequency of temperature and precipitation events, threatens the storage of carbon in northern latitudes. One key concern is how these events will affect the production, mobilization, and export of dissolved organic carbon (DOC), the main form of aquatic carbon export in these regions. In this study, we retrospectively show contrasting effects of climate extremes over 23 years on two adjacent boreal catchments, one dominated by forest cover and the other draining a mire (wetland), despite experiencing the same extreme climate events. During the peak snowmelt, DOC concentrations ranged from 20 to 33 mg l−1 in the forest catchment and 10–28 mg l−1 in the mire catchment respectively, highlighting large inter-annual variation in the springtime hydrologic C export at both sites. We used climate and discharge variables to predict this variation, and found that DOC from the forested catchment, which is derived largely from riparian soils, had the highest concentrations following cold summers, dry autumns, and winters with high precipitation. By contrast, in the mire outlet, where DOC is primarily derived from decomposing peat, the highest DOC concentrations in the spring followed cold/dry winters and dry summers. Our results indicate that processes regulating stream DOC concentrations during spring in both catchments were dependent on both temperature and precipitation in multiple seasons. Together, these patterns suggest that DOC responses to climatic extremes are complex and generate variable patterns in springtime concentrations that are strongly dependent upon landscape context.
Stability results for martingale representations: The general case
Authors: Papapantoleon Antonis , Possamaï Dylan , Saplaouras Alexandros
Published: May 2019

In this paper, we obtain stability results for martingale representations in a very general framework. More specifically, we consider a sequence of martingales, each adapted to its own filtration, and a sequence of random variables measurable with respect to those filtrations. We assume that the terminal values of the martingales and the associated filtrations converge in the extended sense, and that the limiting martingale is quasi left continuous and admits the predictable representation property. Then we prove that each component in the martingale representation of the sequence converges to the corresponding component of the martingale representation of the limiting random variable relative to the limiting filtration, under the Skorokhod topology. This extends in several directions earlier contributions in the literature and has applications to stability results for backward stochastic differential equations with jumps, and to discretization schemes for stochastic systems.
A single tyrosine phosphorylation site in cortactin is important for filopodia formation in neuronal growth cones
Authors: Ren Yuan , He Yingpei , Brown Sherlene , Zbornik Erica , Mlodzianoski Michael J. , Ma Donghan , Huang Fang , Mattoo Seema , Suter Daniel M.
Published: May 2019

Cortactin is a Src tyrosine phosphorylation substrate that regulates multiple actin-related cellular processes. While frequently studied in nonneuronal cells, the functions of cortactin in neuronal growth cones are not well understood. We recently reported that cortactin mediates the effects of Src tyrosine kinase in regulating actin organization and dynamics in both lamellipodia and filopodia of Aplysia growth cones. Here, we identified a single cortactin tyrosine phosphorylation site (Y499) to be important for the formation of filopodia. Overexpression of a 499F phospho-deficient cortactin mutant decreased filopodia length and density, whereas overexpression of a 499E phospho-mimetic mutant increased filopodia length. Using an antibody against cortactin pY499, we showed that tyrosine-phosphorylated cortactin is enriched along the leading edge. The leading edge localization of phosphorylated cortactin is Src2-dependent, F-actin–independent, and important for filopodia formation. In vitro kinase assays revealed that Src2 phosphorylates cortactin at Y499, although Y505 is the preferred site in vitro. Finally, we provide evidence that Arp2/3 complex acts downstream of phosphorylated cortactin to regulate density but not length of filopodia. In conclusion, we have characterized a tyrosine phosphorylation site in Aplysia cortactin that plays a major role in the Src/cortactin/Arp2/3 signaling pathway controlling filopodia formation.
Death by a Thousand Cuts: Stress Exposure and Black–White Disparities in Physiological Functioning in Late Life
Authors: Boen Courtney
Published: May 2019

Objectives

This paper investigates Black–White differences in stress—including diverse measures of chronic, acute, discrimination-related, and cumulative stress exposure—and examines whether race differences in these stress measures mediate Black–White disparities in C-reactive protein (CRP) and metabolic dysregulation in later life.

Methods

Using data from the Health and Retirement Study (HRS) (2004–2012), this study uses stepwise ordinary least squares (OLS) regression models to examine the prospective associations between multiple stressors—including traumatic and stressful life events, financial strain, chronic stress, everyday and major life discrimination, and measures of cumulative stress burden—and CRP and metabolic dysregulation. Mediation analyses assessed the contribution of stress exposure to Black–White disparities in the outcomes.

Results

Blacks experienced more stress than Whites across domains of stress, and stress exposure was strongly associated with CRP and metabolic dysregulation. Race differences in financial strain, everyday and major life discrimination, and cumulative stress burden mediated Black–White gaps in the outcomes, with measures of cumulative stress burden mediating the greatest proportion of the racial disparities.

Discussion

The “thousand cuts” that Blacks experience from their cumulative stress exposure across domains of social life throughout the life course accelerate their physiological deterioration relative to Whites and play a critical role in racial health disparities at older ages.