bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of ion migration in CH3NH3PbI3 perovskite solar cells by transient capacitance measurements
Authors: Futscher Moritz H. , Lee Ju Min , McGovern Lucie , Muscarella Loreta A. , Wang Tianyi , Haider Muhammad Irfan , Fakharuddin Azhar , Schmidt-Mende Lukas , Ehrler Bruno
Published: April 2019

We quantify activation energy, concentration, and diffusion coefficient of mobile ions in MAPbI3 perovskite solar cells using transient ion-drift measurements.
Tuning the aggregation of an amphiphilic anionic calix[5]arene by selective host–guest interactions with bola-type dications
Authors: Pisagatti Ilenia , Barbera Lucia , Gattuso Giuseppe , Villari Valentina , Micali Norberto , Fazio Enza , Neri Fortunato , Parisi Melchiorre F. , Notti Anna
Published: April 2019

Bola-type dications of different length drive the formation of head-to-tail or capsular supramolecular amphiphiles and, in turn, that of the final aggregates.
Detection of molecular behavior that characterizes systems using a deep learning approach
Authors: Endo Katsuhiro , Yuhara Daisuke , Tomobe Katsufumi , Yasuoka Kenji
Published: April 2019

Deep learning approach is applied to detect the representative molecular behavior from the enormous and complex molecular dynamics data.
Shape modulation of squaramide-based supramolecular polymer nanoparticles
Authors: Saez Talens Victorio , Makurat D. M. M. , Liu Tingxian , Dai Wei , Guibert Clément , Noteborn Willem E. M. , Voets Ilja K. , Kieltyka Roxanne E.
Published: April 2019

We report the synthesis and self-assembly of a library of squaramide-based bolaamphiphiles with variable hydrophobic and hydrophilic domain sizes to understand their effect on the formation of supramolecular polymer nanoparticles.
Synthesis of Bisflavanol-Type Natural Products and Their Analogues­ via Self-Coupling of C8-Methylol Catechin Derivatives
Authors: Huang Deng-Ming , Li Hui-Jing , Zhao Yan , Wu Yan-Chao
Published: April 2019

A highly efficient and regioselective self-coupling of C8-methylol catechin derivatives is developed for the synthesis of dimeric flavanol analogues under metal-free and mild conditions. Its applicability is showcased by the efficient synthesis of bisflavanol-type natural products bis-8,8′-catechinylmethane, bis-8,8′-epicatechinylmethane, talienbisflavan A, and oolonghomobisflavan A. The novel self-coupling mechanism sheds new light on the classical Friedel–Crafts alkylation mechanism in acid-catalyzed catechin–formaldehyde condensation.
Neuropathologic Findings in a Child with a Novel Variant of TBCK-Related Encephaloneuronopathy
Authors: Chen Sonja , Zakka Fouad , Khedr Salwa , Mangray Shamlal , Massingham Lauren , de la Monte Suzanne M.
Published: April 2019

A 3-year-old girl with developmental delays, hypotonia, and generalized seizures was diagnosed with a novel variant of a heterozygous mutation in the TBC1 domain containing kinase (TBCK) gene. Postmortem findings revealed severe hypotrophy of cerebral white matter, hypogenesis of the corpus callosum with reduced myelination and oligodendrocyte populations, and reactive gliosis, and venous angiomas of the cerebrum, brainstem, and cerebellum white matter. This report is the first to link a TBCK gene mutation to impaired white matter development with the targeting of central nervous system myelin and oligodendrocytes. The mechanism may involve inhibition of signaling through (mTORC1).
Radial transport modeling of high density deuterium plasmas in proto-MPEX with the B2.5-Eirene code
Authors: Rapp J. , Owen L. W. , Canik J. , Lore J. D. , Caneses J. F. , Kafle N. , Ray H. , Showers M.
Published: April 2019

High density (≥6 × 1019 m−3), low temperature (2–6 eV) helicon discharges in the Prototype Material Plasma Exposure eXperiment (Proto-MPEX) are analyzed with the coupled multifluid plasma, kinetic neutrals code B2.5-Eirene. The interpretative analyses are constrained by data from multiple diagnostics, including Langmuir probes, Mach probes, filterscopes, infrared TV system, Thomson scattering, and baratrons. The objectives of the transport simulations include: investigation of the effects of heating, fueling, and plasma production; pumping, and assumed radial transport models on the calculated density and temperature distributions; plasma flow profiles and power balance. The primary objective in this report is to investigate the effects of the radial transport model in full plasma (the entire length of the plasma column in Proto-MPEX) data-constrained simulations. Results from three assumed forms of the radial transport coefficients are presented, including spatially constant, radially decreasing, and Bohm (D,χ ∼ Te/|B|). The results from each of the three transport coefficient sets agree qualitatively with the core (near axis) data. With the implicit Te dependence, the Bohm coefficients tend to decrease as functions of radius, although not as strongly as the centrally peaked set. The axial variation in the Bohm coefficients is largely due to the axial structure of the magnetic field. The agreement of the simulations and the diagnostic data with the Bohm set indicates that transport in the plasma column of Proto-MPEX is dominated by Bohm diffusion.
Following the nucleation pathway from disordered liquid to gyroid mesophase
Authors: Marriott Maile , Lupi Laura , Kumar Abhinaw , Molinero Valeria
Published: April 2019

Mesophases have order intermediate between liquids and crystals and arise in systems with frustration, such as surfactants, block copolymers, and Janus nanoparticles. The gyroid mesophase contains two interpenetrated, nonintersecting chiral networks that give it properties useful for photonics. It is challenging to nucleate a gyroid from the liquid. Elucidating the reaction coordinate for gyroid nucleation could assist in designing additives that facilitate the formation of the mesophase. However, the complexity of the gyroid structure and the extreme weakness of the first-order liquid to gyroid transition make this a challenging quest. Here, we investigate the pathway and transition states for the nucleation of a gyroid from the liquid in molecular simulations with a mesogenic binary mixture. We find that the gyroid nuclei at the transition states have a large degree of positional disorder and are not compact, consistent with the low surface free energy of the liquid-gyroid interface. A combination of bond-order parameters for the minor component is best to describe the passage from liquid to gyroid, among those we consider. The committor analyses, however, show that this best coordinate is not perfect and suggests that accounting for the relative ordering of the two interpenetrated networks in infant nuclei, as well as for signatures of ordering in the major component of the mesophase, would improve the accuracy of the reaction coordinate for gyroid formation and its use to evaluate nucleation barriers. To our knowledge, this study is the first to investigate the reaction coordinate and critical nuclei for the formation of any mesophase from an amorphous phase.
Application of causality analysis on nuclear reactor systems
Authors: Chionis D. , Dokhane A. , Ferroukhi H. , Pautz A.
Published: April 2019

Causality analysis is a substantial tool for identifying cause-and-effect links between different components of a system and has been extensively used in various areas of science such as neuroscience, climatology, and econometrics. This analysis is carried out in terms of the renormalized partial directed coherence and the directed transfer function connectivity measures. Applying such analysis in the nuclear reactor field is of paramount importance since it can help in inferring cause-and-effect relationships between highly coupled processes, and consequently, it can assist on the safe and reliable operation of a nuclear power plant during the occurrence of possible disturbances or malfunctions. The effectiveness of the connectivity analysis is demonstrated through several simulated and measured test cases. Results show that the connectivity analysis is able to identify accurately the importance and central role of the activation signal when it is applied on a simple analytical model and a simulated nuclear reactor system. In addition, the application on more realistic and complex measured data sets of a Swiss boiling water reactor illustrates the capability of this analysis to indicate possible causes behind the observed anomalies or trends observed at certain conditions and, more importantly, allows a better understanding of the underlying interactions among different neutronic and thermal-hydraulic processes.
A 6.6 ps RMS resolution time-to-digital converter using interleaved sampling method in a 28 nm FPGA
Authors: Xia Haojie , Cao Guiping , Dong Ning
Published: April 2019

Based on the adaptive logic module structure implemented in a 28 nm field programmable gate array (FPGA), we propose an interleaved sampling method, together with bin realignment operation, to enable time-to-digital converter (TDC) implementation. The tap status is sampled twice in a single physical channel, meaning that TDC precision beyond the cell delay limit can be anticipated. Two TDC channels were implemented in a 28 nm Cyclone-V FPGA, and the effectiveness of the proposed method was evaluated. After calibration, the TDC produced a timing resolution of 6.6 ps root mean square or 5.8 ps per least significant bit.
Decay estimates of nonlocal diffusion equations in some particle systems
Authors: Yang Xiaolei , Tang Yanbin
Published: April 2019

In this paper, we first consider a nonlocal mixed diffusion equation ∂tu(t,x)=Lu(t,x) in multiparticle systems with different spatial distributions, where the combination of nonlocal diffusion operators L in a spatial variable is defined by the improper integrals with kernels Jj(x) and the low frequencies of Ĵj(ξ) have the same kind of asymptotic expansions. We use the energy method to establish the decay estimates of solutions to ∂tu(t,x)=Lu(t,x) with initial condition u(0, x) = u0(x). Finally, we consider an anisotropic single-particle equation with nonlocal operator L is defined by the improper integrals with kernels Jj(xj) and it is a generation of an anisotropic nonlocal operator −∑j=1N(−∂xjxj)αj.
Regularized differential evolution for a blind phase retrieval problem in ultrashort laser pulse characterization
Authors: Gerth D. , Escoto E. , Steinmeyer G. , Hofmann B.
Published: April 2019

Obtaining the temporal shape of an ultrashort laser pulse using the method of dispersion scan entails solving a nonlinear inverse problem, a challenging prospect on its own, yet still aggravated when the pulse shape being measured is temporally varying from pulse to pulse. For this purpose, we use a Differential Evolution (DE) algorithm enhanced by three different regularization methods. The DE algorithm in its standard form is insufficient for reconstructing the pulse in the case of unstable pulse trains. By modifying it to retrieve two independent functions and with the help of regularization, we were able to show that it is possible to simultaneously infer the average length and the coherence length of the pulses. The latter is the shortest pulse the laser source can produce. We also discuss the three different approaches for regularization used in this paper, and from the numerical results we present, we can conclude that a spline-based regularization method is far superior compared to the two other methods under investigation.
Energetics of native defects in ZnRh2O4 spinel from hybrid density functional calculations
Authors: Simalaotao Kodchakorn , Reunchan Pakpoom , Umezawa Naoto , T-Thienprasert Jiraroj , Boonchun Adisak
Published: April 2019

Most transparent conducting oxides (TCOs) exhibit n-type conductivity and are difficult to dope into p-type. Therefore, the development of efficient p-type TCOs is challenging. ZnRh2O4 spinel has been recognized as a potential p-type TCOs. However, the source of its p-type conductivity has not been elucidated. In this study, we used hybrid density functional calculations to investigate the energetics and electronic properties of native defects in ZnRh2O4, including vacancies, interstitials, and cation antisites. We found that all acceptor-type defects including Zn vacancies, Zn antisites, and Rh vacancies acted as deep centers. Charge neutrality analysis suggested that undoped ZnRh2O4 may behave as a p-type semiconductor with hole concentrations of 1018–1019 cm−3 under the extreme O-rich/Rh-poor growth condition in which ZnRh has a low formation energy and acts as the major source of hole carriers. However, under realistic growth conditions, the experimentally determined hole concentration significantly exceeds that which is calculated. Our results suggest that native point defects are unlikely to be responsible for the high hole concentrations observed in ZnRh2O4 spinel.
Indium silicon oxide thin films for infrared metaphotonics
Authors: Britton W. A. , Zhang R. , Shrestha S. , Chen Y. , Yu N. , Dal Negro L.
Published: April 2019

We demonstrate silicon-doped indium oxide (ISO) with tunable epsilon near-zero and plasmonic behavior and propose it as a Si-compatible alternative material for metaphotonic applications in the mid-infrared (MIR) spectral range. ISO thin films were grown using DC and RF magnetron cosputtering deposition. Post-deposition thermal annealing was performed that resulted in large tunability of the optical dispersion data, as measured directly by variable-angle ellipsometry. Screened plasma wavelengths in the range 1.7 μm–5.8 μm were experimentally obtained depending on the annealing conditions. Moreover, ISO films with 350 nm thickness were investigated by atomic force microscopy that reveals a maximum rms roughness of 1.9 nm, enabling high-quality nanofabrication. In order to demonstrate the suitability of ISO thin films for the fabrication of plasmonic structures, we have produced ISO nanoparticle disk arrays using electron-beam lithography on Al2O3 substrates and shown, using both finite element method simulations and Fourier transform infrared spectroscopy, distinctive plasmonic resonances at MIR wavelengths tuned by the nanoparticles' spacing and aspect ratio. A figure of merit based on Mie theory is computed for spheres whose radii are either λ/10 or λ/3 over a broad spectral range that enables quantitative comparison with alternative plasmonic materials and reveals the full potential of ISO for engineering localized surface plasmons across the MIR spectral range. The development of fully Si-compatible plasmonic materials with engineered optical dispersion is important to enable cost-effective photonic-plasmonic high-density device integration for metaphotonic research.
Midinfrared real-time polarization imaging with all-dielectric metasurfaces
Authors: Yan Chao , Li Xiong , Pu Mingbo , Ma Xiaoliang , Zhang Fei , Gao Ping , Liu Kaipeng , Luo Xiangang
Published: April 2019

Polarization is an inherent property of light that contains information that is usually ignored by intensity-based sensors. A polarization imaging system forms the images over an extended scene in different polarization basis sets, which is widely used in fields ranging from target detection to biosensing. Typically, conventional polarization imaging systems based on polarization filtering form images only for linearly polarized light and use bulky and complex elements. Here, we proposed an all-silicon metasurface for midinfrared (MIR) active-illumination polarization imaging. The metasurface operates at a wavelength of 10.6 μm and functions as a division of focal plane imaging mask. In experiment, the single-layered metasurface can simultaneously form images in two orthogonal polarization basis sets in a real-time condition, which realizes both linear polarization imaging and chiral imaging. This work unveils the potential of compact MIR polarization detection metasystems.
Internal magnetic field distribution in plasmas
Authors: Tymchyshyn V. B. , Lev B. I. , Zagorodny A. G.
Published: April 2019

We calculate stationary probability distribution of a magnetic field, generated by moving charges of the plasma environment, and stationary probability distribution of force, acting on a charged particle in this environment, with the magnetic interaction taken into account. While the former happens to be the Holtsmark distribution, the latter is a modified Holtsmark distribution. In contrast to prior studies, we did no assumptions on the velocity distribution function and thus the obtained results should be applicable to a wider spectrum of models (with any velocity distribution—not only plasma may be considered). The presented results can be experimentally verified through studies of the Zeeman effect or movement of small charged Brownian particles in plasma.
Leakage and breakdown mechanisms of GaN vertical power FinFETs
Authors: Xiao Ming , Gao Xiang , Palacios Tomás , Zhang Yuhao
Published: April 2019

This work studies the leakage and breakdown mechanisms of 1.2 kV GaN vertical power FinFETs with edge termination. Two competing leakage and breakdown mechanisms have been identified. The first mechanism is dominated by the electric field, with the leakage current dominated by the electric field in the drift region and destructive breakdown voltage by the peak electric field at the edge termination. The second leakage and breakdown mechanism is controlled by an energy (or potential) barrier in the fin channel. This energy barrier suffers from the drain-induced barrier lowering (DIBL) effect and is highly dependent on gate/drain biases, fin geometries, and GaN/oxide interface charges. The electrons injected into the drift region due to the DIBL effect further lead to trap-assisted space-charge-limited conduction, which results in a nondestructive early breakdown. The barrier height in the fin channel determines which mechanism is dominant; the same device could show either destructive or nondestructive breakdown at different gate biases. To enable the normally off power switching, it is important to suppress the leakage from the second mechanism and maintain a sufficiently high energy barrier in the fin channel up to high drain voltages. Finally, the key device parameters determining the energy barrier in the fin channel have been identified. The findings in this work provide critical device understanding and design guidelines for GaN vertical power FinFETs and other “junctionless” vertical high-voltage power transistors.
Laser-driven semiconductor switch for generating nanosecond pulses from a megawatt gyrotron
Authors: Picard Julian F. , Schaub Samuel C. , Rosenzweig Guy , Stephens Jacob C. , Shapiro Michael A. , Temkin Richard J.
Published: April 2019

A laser-driven semiconductor switch (LDSS) employing silicon (Si) and gallium arsenide (GaAs) wafers has been used to produce nanosecond-scale pulses from a 3 μs, 110 GHz gyrotron at the megawatt power level. Photoconductivity was induced in the wafers using a 532 nm laser, which produced 6 ns, 230 mJ pulses. Irradiation of a single Si wafer by the laser produced 110 GHz RF pulses with a 9 ns width and >70% reflectance. Under the same conditions, a single GaAs wafer yielded 24 ns 110 GHz RF pulses with >78% reflectance. For both semiconductor materials, a higher value of reflectance was observed with increasing 110 GHz beam intensity. Using two active wafers, pulses of variable length down to 3 ns duration were created. The switch was tested at incident 110 GHz RF power levels up to 600 kW. A 1-D model is presented that agrees well with the experimentally observed temporal pulse shapes obtained with a single Si wafer. The LDSS has many potential uses in high power millimeter-wave research, including testing of high-gradient accelerator structures.
Simulation and optimization of current generation in gallium phosphide nanowire betavoltaic devices
Authors: Wagner D. , Novog D. R. , LaPierre R. R.
Published: April 2019

The geometry of a gallium phosphide nanowire (NW) array has been optimized for maximum current generation in a betavoltaic (BV) device. The energy capture efficiency for various device geometries with different radioisotope source compounds was calculated in GEANT4. A validation of GEANT4 for BV device simulation was performed by comparing a model output with the available bulk semiconductor BV performance data, followed by predictions of the performance of NW-based devices. The pitch and the diameter of the NWs were found to have the most significant impact on the β-generated current density, with the optimum diameter-to-pitch ratios ranging from 0.55 to 0.8, depending on the source. The energy capture efficiency improved when low energy beta (β) emitters were used. For devices utilizing 63Ni source compounds, the β-generated current densities approached 0.95 μA cm−2, representing an improvement by a factor as high as 5.8 compared to planar devices. In the case of 3H source compounds, the generated current density was 3.05 μA cm−2, a factor of 15.5 larger than comparable planar devices. However, NW devices utilizing sources with a higher decay energy, such as 147Pm, did not demonstrate any improvements over planar geometries. Using the results for optimum NW geometries, NW-based or other nanostructured devices could be made to surpass the present commercial BV batteries.
Predicting milk fatty acids and energy balance of dairy cows in Australia using milk mid-infrared spectroscopy
Authors: Ho P. N. , Marett L. C. , Wales W. J. , Axford M. , Oakes E. M. , Pryce J. E.
Published: April 2019

Mid-infrared spectroscopy (MIRS) is traditionally used for analysing milk fat, protein and lactose concentrations in dairy production, but there is growing interest in using it to predict difficult, or expensive-to-measure, phenotypes on a large scale. The resulting prediction equations can be applied to MIRS data from commercial herd-testing, to facilitate management and feeding decisions, or for genomic selection purposes. We investigated the ability of MIRS of milk samples to predict milk fatty acids (FAs) and energy balance (EB) of dairy cows in Australia. Data from 240 Holstein lactating cows that were part of two 32-day experiments, were used. Milk FAs were measured twice during the experimental period. Prediction models were developed using partial least-square regression with a 10-fold cross-validation. Measures of prediction accuracy included the coefficient of determination (R2cv) and root mean-square error. Milk FAs with a chain length of ≤16 were accurately predicted (0.89 ≤ R2cv ≤ 0.95), while prediction accuracy for FAs with a chain length of ≥17 was slightly lower (0.72 ≤ R2cv ≤ 0.82). The accuracy of the model prediction was moderate for EB, with the value of R2cv of 0.48. In conclusion, the ability of MIRS to predict milk FAs was high, while EB was moderately predicted. A larger dataset is needed to improve the accuracy and the robustness of the prediction models.
Comparative analysis of milk microRNA in the therian lineage highlights the evolution of lactation
Authors: Lefèvre Christophe , Venkat Pooja , Kumar Amit , Modepalli Vengamanaidu , Nicholas Kevin R.
Published: April 2019

Milk is a complex secretion that has an important role in mammalian reproduction. It is only recently that sequencing technologies have allowed the identification and quantification of microRNA (miRNA) in milk of a growing number of mammalian species. This provides a novel window on the study of the evolution and functionality of milk through the comparative analysis of milk miRNA content. Here, milk miRNA sequencing data from five species (one marsupial (tammar wallaby) and four eutherians (human, mouse, cow and pig)) have been retrieved from public depositories and integrated in order to perform a comparison of milk miRNA profiles. The study shows that milk miRNA composition varies widely between species, except for a few miRNAs that are ubiquitously expressed in the milk of all mammals and indicates that milk miRNA secretion has broadly evolved during mammalian evolution. The putative functions of the most abundant milk miRNAs are also discussed.
Network cloning using DNA barcodes
Authors: Shuvaev Sergey A. , Başerdem Batuhan , Zador Anthony M. , Koulakov Alexei A.
Published: April 2019

Significance

The connections between neurons determine the computations performed by a neural network. Connections can be considered a “summary” of the statistical structure of the experience—data—on which the network was trained. Here, we propose a method for how neuronal network connectivity can be copied or “cloned” from one network to another. Our method relies on the use of DNA barcodes—short DNA sequences that allow tagging individual neurons with unique labels. In our study, we prove theorems that show that such a transfer of network connectivity is theoretically possible.
An oscillator model better predicts cortical entrainment to music
Authors: Doelling Keith B. , Assaneo M. Florencia , Bevilacqua Dana , Pesaran Bijan , Poeppel David
Published: April 2019

Significance

Previous work in humans has found rhythmic cortical activity while listening to rhythmic sounds such as speech or music. Whether this activity reflects oscillatory dynamics of a neural circuit or instead evoked responses to the rhythmic stimulus has been difficult to determine. Here, we devised a metric to tease apart the two hypotheses by analyzing phase lag across many stimulation rates. We test this phase concentration metric using numerical simulations and generate quantitative predictions to compare against recorded magnetoencephalography data. Both previously recorded and new data were better predicted by a model of oscillatory dynamics than evoked responses. This work, therefore, provides definitive evidence for the presence of an oscillatory dynamic in auditory cortex during processing of rhythmic stimuli.
Formation and surface-stabilizing contributions to bare nanoemulsions created with negligible surface charge
Authors: Carpenter Andrew P. , Tran Emma , Altman Rebecca M. , Richmond Geraldine L.
Published: April 2019

The stabilization of nanoemulsions, nanosized oil droplets dispersed in water, is commonly achieved through the addition of surfactants and polymers. However, nanoemulsions in the absence of emulsifiers have been observed to acquire a significant negative charge at their surface, which ultimately contributes to their stability. While the source of this negative charge is disputed to this day, its presence is taken as an inherent property of the aqueous–hydrophobic interface. This report provides a look at the molecular structure and bonding characteristics of bare aqueous–hydrophobic nanoemulsion interfaces. We report the creation of bare nanoemulsions with near zero surface charge, which are marginally stable for several days. The process of creating these low-charge nanoemulsions (LCNEs) required rigorous cleaning procedures and proper solvent storage conditions. Using vibrational sum-frequency scattering spectroscopy, we measure the structure and bonding of the interfacial aqueous and hydrophobic phases. The surfaces of these LCNE samples possess a measurable free OH vibration, not found in previous studies and indicative of a clean interface. Tuning the nanoemulsion charge through addition of anionic surfactants, modeling potential surface-active contaminants, we observe the free OH to disappear and a reorientation of the interfacial hydrophobic molecules at micromolar surfactant concentrations. Notably, the free OH vibration provides evidence for stronger dispersion interactions between water molecules and the hydrophobic phase at the LCNE surface compared with similar planar water–alkane interfaces. We propose the stronger bonding interactions, in addition to an ordered interfacial aqueous layer, contribute to the delayed droplet coalescence and subsequent phase separation.
Collaboration and competition between active sheets for self-propelled particles
Authors: Laskar Abhrajit , Shklyaev Oleg E. , Balazs Anna C.
Published: April 2019

Significance

Chemical and density gradients produced by catalytic reactions provide effective means of propelling particles in fluid-filled microchambers. Using computer modeling, we show the rich dynamic behavior that emerges when catalyst-coated sheets are combined with chemoresponsive particles in solution. Catalytic reactions on the flexible sheets generate density variations that produce fluid flows, which deform the sheets and drive their movement. The same reactions yield the chemical gradients that direct the particles’ motion. The resulting synergistic interactions among the sheets, particles, and fluid lead to bioinspired behavior, such as crab-shaped sheets competitively grabbing or collaboratively sharing particles, which can also flee these predators. By identifying parameters that govern the systems’ behavior, we provide guidelines for creating chemically driven, flexible robots for fluidic environments.
Partial inhibition of the overactivated Ku80-dependent DNA repair pathway rescues neurodegeneration in
C9ORF72
-ALS/FTD
Authors: Lopez-Gonzalez Rodrigo , Yang Dejun , Pribadi Mochtar , Kim Tanya S. , Krishnan Gopinath , Choi So Yoen , Lee Soojin , Coppola Giovanni , Gao Fen-Biao
Published: April 2019

Significance

GGGGCC (G
4
C
2
) repeat expansion in the
C9ORF72
gene is the most common genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Several dysregulated downstream molecular pathways have been identified; however, it is not known which pathway is primarily responsible for neurodegeneration, and effective therapeutic approaches remain elusive. In cellular and animal models of
C9ORF72
-ALS/FTD, we found that partial inhibition of an overactivated DNA repair pathway, and of Ku80 in particular, suppresses a cell death pathway, suggesting a therapeutic approach in
C9ORF72-
ALS/FTD.
Shugoshin protects centromere pairing and promotes segregation of nonexchange partner chromosomes in meiosis
Authors: Previato de Almeida Luciana , Evatt Jared M. , Chuong Hoa H. , Kurdzo Emily L. , Eyster Craig A. , Gladstone Mara N. , Gómez-H Laura , Llano Elena , Meyer Régis , Pendas Alberto M. , Pezza Roberto J. , Dawson Dean S.
Published: April 2019

Significance

Meiotic crossovers form a connection between homologous chromosomes that allows them to attach to the spindle as a single unit in meiosis I. In humans, failures in this process are a leading cause of aneuploidy. A recently described process, called centromere pairing, can also help connect meiotic chromosome partners in meiosis. Homologous chromosomes become tightly joined by a structure called the synaptonemal complex (SC) in meiotic prophase. After the SC disassembles, persisting SC proteins at the centromeres mediate their pairing. Here, studies in mouse spermatocytes and yeast are used to show that the shugoshin protein helps SC components persist at centromeres and helps centromere pairing promote the proper segregation of yeast chromosomes that fail to become tethered by crossovers.
The threat from
Chromolaena odorata
and options for control.
Authors: Rusdy M.
Published: April 2019

The invasion of natural ecosystems by alien plant species is a serious environmental problem that threatens the productivity, biodiversity and ecosystem functioning.
Chromolaena odorata
is a weed native to tropical America and has become one of the world's worst alien invasive species in the Old World of tropical and subtropical countries. In invaded areas of the Old World, this plant has created many problems both in natural and disturbed ecosystems. To generate information useful for alleviating the problems, literature in Google Scholar, CAB Abstracts, Web of Science, PubMed and Scopus were searched. From those databases, reproduction, distribution and factors contributing to its success as an invader species are presented and discussed. Its threat to agriculture, natural ecosystem and animals are presented. Means of preventing the spread and controlling the growth of the weed are highlighted and discussed.
The high-fat diet and the effects of its consumption on the hypothalamus and hippocampus.
Authors: Woodie L. N. , Altonji O. M. , Huggins K. W. , Greene M. W.
Published: April 2019

Obesity has become a highly prevalent worldwide public health issue that is attributed to the overconsumption of caloric dense foods, such as meals high in saturated fats. Consistent overconsumption of a high-fat diet (HFD) results in pathogenic adipose tissue expansion which induces a chronic state of low-grade inflammation throughout the body. Extensive research into the area has shown that this inflammatory state has detrimental impacts on metabolic health and lies at the centre of several diseases such as type-II diabetes mellitus, non-alcoholic fatty liver disease and cardiovascular disease. In recent years, cognitive deficits have also been found to result from chronic high-fat feeding. In particular, the hypothalamus and hippocampus are two areas that are consistently impacted by HFD-induced inflammation. The hypothalamus is a main homeostatic site and alterations in its chemistry and function can cause negative impacts though out the entire organism. The hypothalamic role in appetite and satiety, in particular, is significantly altered by the HFD. Additionally, the mammalian centre for learning and memory, the hippocampus, becomes increasingly susceptible to the deleterious effects of HFD-induced inflammation as HFD exposure continues.; Deficits in behavioural, cellular and molecular markers for hippocampal function are consistently observed in animal and human studies on high-fat feeding. The obesity epidemic has continued; to plague Western society making research into the area of HFD-induced diseases increasingly important. Therefore, this review will evaluate and connect the current literature on HFD-induced changes to the brain areas most impacted by the HFD: the hypothalamus and hippocampus.
On the interplay between robustness and dynamic planning for adaptive radiation therapy*
Authors: Böck Michelle , Eriksson Kjell , Forsgren Anders
Published: April 2019

Interfractional geometric uncertainties can lead to deviations of the actual delivered dose from the prescribed dose distribution. To better handle these uncertainties during the course of treatment, the authors propose a framework for robust adaptive radiation therapy in which a variety of robust adaptive treatment strategies are introduced and evaluated. This variety is a result of optimization variables with various degrees of freedom within robust optimization models that vary in their grade of conservativeness. The different degrees of freedom in the optimization variables are expressed through either time-and-uncertainty-scenario-independence, time-dependence or time-and-uncertainty-scenario-dependence, while the robust models are either based on expected-value-, worst-case- or conditional value-at-risk-optimization. The goal of this study is to understand which mathematical properties of the proposed robust adaptive strategies are relevant such that the accumulated dose can be steered as close as possible to the prescribed dose as the treatment progresses. We apply a result from convex analysis to show that the robust non-adaptive approach under conditions of convexity and permutation-invariance is at least as good as the time-dependent robust adaptive approach, which implies that the time-dependent problem can be solved by dynamically solving the corresponding time-independent problem. According to the computational study, non-adaptive robust strategies may provide sufficient target coverage comparable to robust adaptive strategies if the occurring uncertainties follow the same distribution as those included in the robust model. Moreover, the results indicate that time-and-uncertainty-scenario-dependent optimization variables are most compatible with worst-case-optimization, while time-and-uncertainty-scenario-independent variables find their best match with expected value optimization. In conclusion, the authors introduced a novel framework for robust adaptive radiation therapy and identified mathematical requirements to further develop robust adaptive strategies in order to improve treatment outcome in the presence of interfractional uncertainties.
Lifting of locally almost periodicity and some related properties
Authors: Xiao Zubiao
Published: April 2019

The paper is mainly concerned with the lifting of locally almost periodicity of minimal semiflows. Based on this work, we use a different method from Sacker and Sell to get the property of lifting of equicontinuity for semiflows. Moreover, in the case of a group action, we give answers to questions about lifting of almost automorphy for minimal flows posed by Sell, Shen, and Yi [Topological dynamics and differential equations, Amer. Math. Soc., Providence, RI, 1998, pp. 279–298].
The infinite range of infinite Blaschke product
Authors: Dong Xin-Han , Ai Wen-Hui , Wu Hai-Hua
Published: April 2019

For an infinite Blaschke product

B
B

, does there necessarily exist

δ
>
0

\delta >0

such that each

w
w

satisfying

|

w

|

>
δ

|w|>\delta

is assumed infinitely often by

B
B

? Stephenson raised this question in 1979 and then constructed a counterexample in 1988 to prove that the answer to his problem is negative. In this paper, we find two sufficient conditions under which the answer to the problem is positive.
The costs of competition: injury patterns in 2 Asian colobine monkeys
Authors: Feder Jacob A , Lu Amy , Koenig Andreas , Borries Carola
Published: April 2019

Aggression rarely escalates to physical conflict because doing so puts individuals at risk of injury. Escalation only pays off when the potential benefits outweigh the potential costs, that is, when resources critical to fitness are at stake. Here, we investigated the occurrence of injury in 2 Asian colobine species: Nepal gray langurs (Semnopithecus schistaceus) and Phayre’s leaf monkeys (Trachypithecus phayrei crepusculus). In both species, younger individuals are higher-ranking and might have greater incentive to fight. However, Nepal gray langurs have a strict breeding season, which may magnify male mating competition, and Phayre’s leaf monkeys, unlike Nepal gray langurs, have female-biased dispersal, which may increase female injury risk during subadulthood. Using long-term data on observed injuries (Nepal gray langurs: n = 208; Phayre’s leaf monkeys: n = 225), we modeled the monthly occurrence of injury (Y/N) and found that males received more injuries than females in both species. Also, subadults generally experienced frequent injury, as young individuals likely face challenges when competing for group membership and/or establishing rank. In Nepal gray langurs, males received 3 times more injuries during the mating season, suggesting strong competition for mates during this period, and females experienced more injuries before conception, suggesting competition to meet the nutritional requirements for reproduction. Unexpectedly, females in smaller groups received more injuries in Nepal gray langurs. Overall, these results indicate that injuries are most likely when fighting may aid in establishing group membership, achieving high rank, and reproducing. Future research should investigate the influence of injuries on fitness outcomes.
Impact of Intravenous Fluid Therapy on Survival Among Patients With Ebola Virus Disease: An International Multisite Retrospective Cohort Study
Authors: Aluisio Adam R , Yam Derrick , Peters Jillian L , Cho Daniel K , Perera Shiromi M , Kennedy Stephen B , Massaquoi Moses , Sahr Foday , Smit Michael A , Liu Tao , Levine Adam C
Published: April 2019

Background

Intravenous fluid (IVF) is a frequently recommended intervention in Ebola virus disease (EVD), yet its impact on patient outcomes remains unclear.

Methods

This retrospective cohort study evaluated patients with EVD admitted to 5 Ebola treatment units (ETUs) in West Africa. The primary outcome was the difference in 28-day survival between cases treated and not treated with IVF. To control for demographic and clinical factors related to both IVF exposure and survival, cases were compared using propensity score matching. To control for time-varying patient and treatment factors over the course of ETU care, a marginal structural proportional hazards model (MSPHM) with inverse probability weighting was used to assess for 28-day survival differences.

Results

Among 424 EVD-positive cases with data for analysis, 354 (83.5%) were treated with IVF at some point during their ETU admission. Overall, 146 (41.3%) cases treated with IVF survived, whereas 31 (44.9%) cases not treated with any IVF survived (P = .583). Matched propensity score analysis found no significant difference in 28-day survival between cases treated and not treated with IVF during their first 24 and 48 hours of care. Adjusted MSPHM survival analyses also found no significant difference in 28-day survival for cases treated with IVF (27.3%) compared to those not treated with IVF (26.9%) during their entire ETU admission (P = .893).

Conclusions

After adjustment for patient- and treatment-specific time-varying factors, there was no significant difference in survival among patients with EVD treated with IVF as compared to those not treated with IVF.
Short- vs. long-term dual antiplatelet therapy in secondary prevention for ischaemic stroke: a network metanalysis
Authors: Pugliese Francesca , Arasaratnam Punitha , Moellenberg Marcus , Dani Sourbha
Published: April 2019

Aims 

This review aimed to compare the efficacy and safety of short-term (≤3 months) and long-term (≥1 year) dual-antiplatelet therapy (DAPT) in secondary prevention for ischaemic stroke.

Methods and results 

We searched MEDLINE, EMBASE (Ovid), PubMed, Cochrane Library, ClinicalTrials.gov, and Google Advanced Search for randomized controlled trials. The population consisted of patients with recent ischaemic stroke or transient ischaemic attack. The intervention was DAPT with a combination of aspirin, clopidogrel, and dipyridamole compared to either aspirin or clopidogrel in monotherapy. The primary outcome was the rate of all recurrent stroke (ischaemic and haemorrhagic). Secondary outcomes were ischaemic stroke, all bleeding, severe bleeding, all-cause death, cardiovascular death, and myocardial infarction. Data were pooled by network metanalysis and pairwise metanalyses. Sixteen studies with 55 261 participants were included. Compared to aspirin, DAPT with aspirin clopidogrel decreased the risk of recurrent stroke [short-term odds ratio (OR) 0.67, 95% confidence interval (CI) 0.58–0.77; long-term OR 0.84, 95% CI 0.70–1.01] at the expense of increased risk of bleeding (short-term OR 1.76, 95% CI 1.26–2.46; long-term OR 2.25, 95% CI 1.97–2.57). Dual antiplatelet therapy with aspirin clopidogrel and clopidogrel in monotherapy had similar long-term risk of recurrent stroke (OR 0.98, 95% CI 0.83–1.14), but DAPT was associated with increased risk of bleeding (OR 2.77, 95% CI 2.21–3.46). Network metanalysis showed that short-term aspirin clopidogrel DAPT had the best risk-benefit profile, followed by long-term aspirin clopidogrel DAPT and clopidogrel alone. Aspirin dipyridamole DAPT was less effective.

Conclusion 

Short-term DAPT had better risk-benefit profile than long-term DAPT.
Associations of Impaired Renal Function With Declines in Muscle Strength and Muscle Function in Older Men: Findings From the CHAMP Study
Authors: Toyama Tadashi , van den Broek-Best Oliver , Ohkuma Toshiaki , Handelsman David , Waite Louise M , Seibel Markus J , Cumming Robert , Naganathan Vasi , Sherrington Cathie , Hirani Vasant , Wang Amanda Y
Published: April 2019

Background

Advanced kidney disease is associated with reduced muscle strength and physical performance. However, associations between early stages of renal impairment and physical outcomes are unclear.

Methods

The Concord Health and Ageing in Men Project is a prospective study of 1,705 community-dwelling men aged 70 years and older. Participants with estimated glomerular filtration rate (eGFR) more than 30 mL/min/1.73 m2 were included and further divided into four eGFR categories. Physical parameters including grip strength, gait speed, appendicular lean mass (ALM, a sum of skeletal mass of arms and legs), ALM adjusted for body mass index (ALMBMI), and muscle function (measured using grip strength divided by arm lean mass) were assessed at both baseline and 5-year follow-up. Associations between kidney function and changes in physical parameters were analyzed using linear and logistic regression models.

Results

Our study included 789 men with a median age of 75 years and median eGFR of 72 mL/min/1.73 m2 at baseline. Over 5 years, grip strength, gait speed, ALMBMI, and muscle function all declined in the whole cohort, compared with baseline. The multivariable analyses showed that poorer renal function was associated with more rapid declines in grip strength, gait speed, and muscle function in participants with mild-to-moderate renal impairment (GFR category stage G3, eGFR < 60 mL/min/1.73 m2) (p = .01, p < .01, p = .02, respectively) but less so in those with eGFR more than 60 mL/min/1.73 m2, whereas eGFR category did not have a significant impact on declines in ALMBMI. These results remained unchanged with or without adjustment for age.

Conclusions

In community-dwelling older men, mild-to-moderate renal impairment at baseline was associated with declines in grip strength, gait speed, and muscle function over time despite preservation of muscle mass.
Use of 3-dimensional computed tomography for planning a complex sleeve bronchoplasty with total parenchyma-sparing resection of a carcinoid tumour in the right main bronchus
Authors: Betser Léa , De Wolf Julien , Glorion Matthieu , Chapelier Alain
Published: April 2019

Bronchoplasty is frequently required for radical resection of central typical carcinoid tumours. As sleeve bronchoplasty can be a complex procedure, an accurate evaluation of the tumour location is mandatory. Although the endobronchial part of the tumour can be easily evaluated by bronchoscopy, the exo-bronchial part is difficult to analyse with a standard computed tomography (CT) scan. A three-dimensional (3D) CT scan could be used to identify this exo-bronchial component of the tumour when planning a reconstruction. Herein, we present a case of a 59-year-old woman with a typical central carcinoid tumour of the right main bronchus. After 3D modelling, we successfully performed a total parenchyma-sparing resection with an intermedius bronchus reimplantation into the carina associated with the right upper bronchus anastomosis in the lateral trachea. The follow-up was uneventful. An endoscopy at 3 months showed excellent results.
Human Cytomegalovirus Genomes Sequenced Directly From Clinical Material: Variation, Multiple-Strain Infection, Recombination, and Gene Loss
Authors: Suárez Nicolás M , Wilkie Gavin S , Hage Elias , Camiolo Salvatore , Holton Marylouisa , Hughes Joseph , Maabar Maha , Vattipally Sreenu B , Dhingra Akshay , Gompels Ursula A , Wilkinson Gavin W G , Baldanti Fausto , Furione Milena , Lilleri Daniele , Arossa Alessia , Ganzenmueller Tina , Gerna Giuseppe , Hubáček Petr , Schulz Thomas F , Wolf Dana , Zavattoni Maurizio , Davison Andrew J
Published: April 2019

The genomic characteristics of human cytomegalovirus (HCMV) strains sequenced directly from clinical pathology samples were investigated, focusing on variation, multiple-strain infection, recombination, and gene loss. A total of 207 datasets generated in this and previous studies using target enrichment and high-throughput sequencing were analyzed, in the process enabling the determination of genome sequences for 91 strains. Key findings were that (i) it is important to monitor the quality of sequencing libraries in investigating variation; (ii) many recombinant strains have been transmitted during HCMV evolution, and some have apparently survived for thousands of years without further recombination; (iii) mutants with nonfunctional genes (pseudogenes) have been circulating and recombining for long periods and can cause congenital infection and resulting clinical sequelae; and (iv) intrahost variation in single-strain infections is much less than that in multiple-strain infections. Future population-based studies are likely to continue illuminating the evolution, epidemiology, and pathogenesis of HCMV.