bluuebunny/crossref_metadata_2025_split huggingface dataset:
The mirtron miR-1010 functions in concert with its host gene SKIP to balance elevation of nAcRβ2
Authors: Amourda Christopher , Saunders Timothy E. 
Published: February 2020

AbstractMirtrons are non-canonical miRNAs arising by splicing and debranching from short introns. A plethora of introns have been inferred by computational analyses as potential mirtrons. Yet, few have been experimentally validated and their functions, particularly in relation to their host genes, remain poorly understood. Here, we found that Drosophila larvae lacking either the mirtron miR-1010 or its binding site in the nicotinic acetylcholine receptor β2 (nAcRβ2) 3′UTR fail to grow properly and pupariate. Increase of cortical nAcRβ2 mediated by neural activity elevates the level of intracellular Ca2+, which in turn activates CaMKII and, further downstream, the transcription factor Adf-1. We show that miR-1010 downregulates nAcRβ2. We reveal that Adf-1 initiates the expression of SKIP, the host gene of miR-1010. Preventing synaptic potentials from overshooting their optimal range requires both SKIP to temper synaptic potentials (incoherent feedforward loop) and miR-1010 to reduce nAcRβ2 mRNA levels (negative feedback loop). Our results demonstrate how a mirtron, in coordination with its host gene, contributes to maintaining appropriate receptor levels, which in turn may play a role in maintaining homeostasis.
Solution-Based Synthesis of Few-Layer WS2 Large Area Continuous Films for Electronic Applications
Authors: Abbas Omar A. , Zeimpekis Ioannis , Wang He , Lewis Adam H. , Sessions Neil P. , Ebert Martin , Aspiotis Nikolaos , Huang Chung-Che , Hewak Daniel , Mailis Sakellaris , Sazio Pier 
Published: February 2020

AbstractUnlike MoS2 ultra-thin films, where solution-based single source precursor synthesis for electronic applications has been widely studied, growing uniform and large area few-layer WS2 films using this approach has been more challenging. Here, we report a method for growth of few-layer WS2 that results in continuous and uniform films over centimetre scale. The method is based on the thermolysis of spin coated ammonium tetrathiotungstate ((NH4)2WS4) films by two-step high temperature annealing without additional sulphurization. This facile and scalable growth method solves previously encountered film uniformity issues. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were used to confirm the few-layer nature of WS2 films. Raman and X-Ray photoelectron spectroscopy (XPS) revealed that the synthesized few-layer WS2 films are highly crystalline and stoichiometric. Finally, WS2 films as-deposited on SiO2/Si substrates were used to fabricate a backgated Field Effect Transistor (FET) device for the first time using this precursor to demonstrate the electronic functionality of the material and further validate the method.
Optimisation of Storage and Transportation Conditions of Cultured Corneal Endothelial Cells for Cell Replacement Therapy
Authors: Wahlig Stephen , Peh Gary S. L. , Adnan Khadijah , Ang Heng-Pei , Lwin Chan N. , Morales-Wong F. , Ong Hon Shing , Lovatt Matthew , Mehta Jodhbir S. 
Published: February 2020

AbstractAs the cornea is one of the most transplanted tissues in the body it has placed a burden on the provision of corneas from cadaveric donors. Corneal endothelial dysfunction is the leading indication for cornea transplant. Therefore, tissue engineering is emerging as an alternative approach to overcome the global shortage of transplant-grade corneas. The propagation and expansion of corneal endothelial cells has been widely reported. However, one obstacle to overcome is the transport and storage of corneal endothelial cells. In this study we investigated whether tissue engineered corneal endothelial cells can be preserved in hypothermic conditions. Human corneal endothelial cells (HCEnCs) were exposed to various temperatures (4 °C, 23 °C, and 37 °C) in both adherent and suspension storage models. Optimal storage media and storage duration was tested along with post-storage viability. Following storage and subsequent recovery at 37 °C, cell phenotype was assessed by immunofluorescence, gene and protein expression, and proliferative capacity analysis. Functionality was also assessed within a rabbit model of bullous keratopathy. Our data support our hypothesis that functional HCEnCs can be preserved in hypothermic conditions.
β-Elemene suppresses tumor growth of diffuse large B-cell lymphoma through regulating lncRNA HULC-mediated apoptotic pathway
Authors: Hu Tonglin , Gao Yu 
Published: February 2020

Abstract
Background: Diffuse large B-cell lymphoma (DLBCL) is considered the most common aggressive subtype of lymphoma. A number of DLBCL patients fail to achieve a response to currently available therapies or develop resistance. β-Elemene is derived from herb Curcuma wenyujin, and exhibits anti-tumor activity in both solid and non-solid tumors through modulating several molecular signaling pathways. We aimed to explore the role of β-elemene in DLBCL treatment and elucidate the involved mechanism.
Materials and methods: Cell viability, apoptosis and expressions of related proteins were assessed and in vivo study were performed to determine the tumor suppressive effect of β-elemene and explore the molecular mechanisms.
Results: β-Elemene significantly suppressed the viability of DLBCL cells, and β-elemene down-regulated the lncRNA HULC expression and regulated key pro-apoptotic and anti-apoptotic proteins to induce significant apoptosis of DLBCL cells. HULC overexpression could decrease the β-elemene induced apoptosis, while HULC knockdown increased the apoptosis in DLBCL cells. In vivo study further confirmed that β-elemene could suppress the growth of DLBCL xenograft and regulate the HULC expression and the critical proteins of the apoptotic pathway.
Conclusion: β-Elemene performs as a tumor suppressor and modulator of HULC-mediated apoptotic pathway in DLBCL and will be an alternative candidate for clinical application.
Clinical characteristics of congenital lamellar cataract and myopia in a Chinese family
Authors: Liu Qing , Zhu Siquan 
Published: February 2020

Abstract
To investigate the clinical characteristics and the genetic defect in a Chinese family with congenital lamellar cataract with myopia. Three generations of a single family were recruited in the present study. A detailed family history and clinical data were recorded. A total of 100 unrelated ethnically matched controls without family history of congenital cataracts and myopia were also recruited. Genomic DNA was extracted from peripheral blood leukocytes. The sequencing of candidate genes was performed to screen out the disease-causing mutation. The effects of amino acid changes on the structure of proteins were predicted by bioinformatics analysis. Affected individuals presented lamellar lens opacities and myopia. Direct sequencing revealed a heterozygous c. 34 C&gt;T variation in the αA-crystallin protein (CRYAA) gene, which resulted in the replacement of a highly conserved arginine by cystine at codon 12 (p.R12C). This mutation co-segregated with all affected individuals and was not observed in unaffected members or the 100 normal controls. Bioinformatic analysis showed that a highly conserved region was located around Arg12, an increase in local hydrophobicity was shown around the substitution site and the secondary structure of the mutant CRYAA protein has been changed. This is the case of a congenital lamellar cataract phenotype with myopia associated with the mutation of Arg12Cys (p.R12C) in CRYAA. Our finding confirms the high rate of mutations at this dinucleotide. In addition, these results demonstrate a myopia susceptibility locus in this region, which might also be associated with the mutation in CRYAA.
The mechanism of hsa-miR-424-5 combining PD-1 through mTORC signaling pathway to stimulate immune effect and participate in Type 1 diabetes
Authors: Wang Guofeng , Yan Yongxin , Zheng Zhichen , Zhang Tongyu 
Published: February 2020

Abstract
In the present study, hsa-miR-424-5p mimic plasmid and hsa-mir-424-5p inhibitor plasmid were designed and injected into rats respectively, and miRNA control plasmid was also constructed. Models of Type 1 diabetes (T1D) were built. After successful modeling, the expression of hsa-miR-424-5p in lymphocytes was analyzed by RT-PCR. The expression of protein PD-1, T-bet, CXCR3, STING in Th1 lymphocytes and content of IGF-1 in islet tissue were analyzed by flow analysis. The protein levels of SHP2, Rheb, mTORC1, Rictor and Raptor in islet tissue were analyzed by Western blot. The results showed that hsa-miR-424-5p mimic group had the highest expression of hsa-miR-424-5p in lymphocytes. The expression of PD-1 was in hsa-miR-424-5p inhibitor &gt; miRNA control &gt; hsa-miR-424-5p mimic, while the expression of T-bet, CXCR3 and STING was in hsa-miR-424-5p mimic &gt; miRNA control &gt; hsa-miR-424-5p inhibitor. The expression of IGF-1 protein in hsa-miR-424-5p inhibitor group was the highest (32.08%) and hardly expressed in hsa-miR-424-5p mimic group (2.36%). The expression of SHP2, Rheb, mTORC1, Rictor and Raptor of insulin histoproteins were in hsa-miR-424-5p mimic group &gt; miRNA control of &gt; hsa-miR-424-5p inhibitor group, with statistical differences. It indicates that hsa-miR-424-5p binding PD-1 signaling molecules can stimulate the immune effect through the mTORC signaling pathway and participates in the pathogenesis of T1D.
Balancing scheme for phase current and flying‐capacitor voltage in three‐level DC–DC converter
Authors: Choi Minho , Kye Chan‐Ho , Jeong Deog‐Kyoon 
Published: February 2020

A balancing scheme for phase current and voltage of the flying capacitor in a fully integrated multi‐level multi‐phase DC–DC converter is proposed. The proposed balancing scheme based on the ripple voltage of the flying capacitor can simultaneously mitigate the imbalance of phase current and voltage of the flying capacitor. A mathematical analysis shows the proposed scheme can obtain the current information of the flying capacitor during charging and discharging operations and finally obtain the average inductor‐current value. A prototype 4‐phase 350 MHz three‐level DC–DC converter shows <4.7% voltage imbalance of the flying capacitor and <36 mA phase‐current imbalance at output voltage and maximum load current of 0.9 V and 1.2 A, respectively.
The MUSE-Faint survey
Authors: Zoutendijk Sebastiaan L. , Brinchmann Jarle , Boogaard Leindert A. , Gunawardhana Madusha L. P. , Husser Tim-Oliver , Kamann Sebastian , Ramos Padilla Andrés Felipe , Roth Martin M. , Bacon Roland , den Brok Mark , Dreizler Stefan , Krajnović Davor 
Published: February 2020

Aims. It has been shown that the ultra-faint dwarf galaxy Eridanus 2 may host a stellar cluster in its centre. If this cluster is shown to exist, it can be used to set constraints on the mass and abundance of massive astrophysical compact halo objects (MACHOs) as a form of dark matter. Previous research has shown promising expectations in the mass range of 10−100 M⊙, but lacked spectroscopic measurements of the cluster. We aim to provide spectroscopic evidence regarding the nature of the putative star cluster in Eridanus 2 and to place constraints on MACHOs as a constituent of dark matter.
Methods. We present spectroscopic observations of the central square arcminute of Eridanus 2 from MUSE-Faint, a survey of ultra-faint dwarf galaxies with the Multi Unit Spectroscopic Explorer on the Very Large Telescope. We derived line-of-sight velocities for possible member stars of the putative cluster and for stars in the centre of Eridanus 2. We discuss the existence of the cluster and determine new constraints for MACHOs using the Fokker–Planck diffusion approximation.
Results. Out of 182 extracted spectra, we identify 26 member stars of Eridanus 2, seven of which are possible cluster members. We find intrinsic mean line-of-sight velocities of 79.7+3.1−3.8 km s−1 and 76.0+3.2−3.7 km s−1 for the cluster and the bulk of Eridanus 2, respectively, as well as intrinsic velocity dispersions of < 7.6 km s−1 (68% upper limit) and 10.3+3.9−3.2 km s−1, respectively. This indicates that the cluster most likely exists as a distinct dynamical population hosted by Eridanus 2 and that it does not have a surplus of dark matter over the background distribution. Among the member stars in the bulk of Eridanus 2, we find possible carbon stars, alluding to the existence of an intermediate-age population. We derived constraints on the fraction of dark matter that can consist of MACHOs with a given mass between 1 and 105 M⊙. For dark matter consisting purely of MACHOs, the mass of the MACHOs must be less than ∼7.6 M⊙ and ∼44 M⊙ at a 68- and 95% confidence level, respectively.
Reactivity of formic acid (HCOOH) with H atoms on cold surfaces of interstellar interest
Authors: Chaabouni Henda , Baouche Saoud , Diana Stephan , Minissale Marco 
Published: February 2020

Context. Formic acid (HCOOH) is the simplest organic carboxylic acid in chemical synthesis and the significant species in interstellar chemistry. HCOOH has been abundantly detected in interstellar ices, dense molecular clouds and star-forming regions.
Aims. Laboratory hydrogenation experiments of HCOOH molecules with H atoms were performed with two cryogenic ultra-high vacuum devices on amorphous solid water ices, and highly oriented pyrolytic graphite surfaces. The aim of this work is to study the reactivity of HCOOH molecules with H atoms at low surface temperature 10 K, low surface coverage of one monolayer to three layers, and low H-atom flux of about 3.0 × 1012 molecule cm−2 s−1.
Methods. HCOOH and H beams were deposited on cold surfaces held at 10 K, and the condensed films were analyzed by in-situ Reflection Absorption InfraRed Spectroscopy and temperature programmed desorption (TPD) mass spectrometry technique by heating the sample from 10 to 200 K.
Results. Using the temperature programmed during exposure desorption technique, we highlight the possible dimerization of HCOOH molecules at low surface temperatures between 10 and 100 K. In our HCOOH+H experiments, we evaluated a consumption of 20–30% of formic acid by comparing the TPD curves at m/z 46 of pure and H-exposed HCOOH ice.
Conclusions. The hydrogenation HCOOH+H reaction is efficient at low surface temperatures. The main products identified experimentally are carbon dioxide (CO2) and water (H2O) molecules. CO bearing species CH3OH, and H2CO are also detected mainly on graphite surfaces. A chemical surface reaction route for the HCOOH+H system is proposed to explain the product formation.
Nonlinear noise suppression in a high-rate optical channel with phase modulation and dispersion compensation
Authors: Shapiro E.G. , Shapiro D.A. 
Published: February 2020

Abstract
We have performed a numerical simulation of transmission of optical DP QPSK signals at a rate of 40 Gbaud over a distance of 2000 km. It is shown that a channel with large negative dispersion and preliminary large positive pulse chirping significantly reduces nonlinear distortion and improves the signal quality. To further reduce the probability of recognition error, it is proposed, instead of a negative dispersion fibre, to use compensators with low attenuation.
Drilling of sub-100 μm hourglass-shaped holes in diamond with femtosecond laser pulses
Authors: Jeong B. , Lee B. , Kim J.-H. , Choi J.-A. , Yang J. , Sall E.G. , Kim J.W. , Heo D. , Jang J. , Kim G.-H. , Yashin V.E. 
Published: February 2020

Abstract
We present images of microholes drilled in diamond using a homemade femtosecond Yb : KGW laser. We use a femtosecond laser source emitting pulses with a duration of 230 fs at a wavelength of 1030 nm, the focusing spot size amounting to 8.9 μm. The effect of the pulse energy and the number of pulses on the microhole geometry (hole diameter, circularity, taper angle, and drilling quality) is evaluated. The obtained results demonstrate the feasibility of drilling of hourglass-shaped holes in a diamond sample, which have similar diameters at the hole entrance (92 μm) and exit (95 μm), but a much smaller diameter (28 μm) at a certain waist section inside the hole.
2D microspatial distribution uniformity of photon detection efficiency and crosstalk probability of multi-pixel photon counters
Authors: Liu Lina , Zhang Chunling , Gallina Giacomo , Zhang Guoqing 
Published: February 2020

Abstract
Two-dimensional (2D) microspatial distribution uniformity of photon detection efficiency (PDE) and optical crosstalk probability P
ct of multi-pixel photon counters (MPPCs) is studied. The experimental results show that the 2D spatial distribution of P
ct is obviously uneven, i.e. P
ct is larger at the corners and edges of a single pixel in MPPCs, which suggest a higher electrical field in the depletion region of the pixel at the corners and edges. The nonuniformity of the 2D spatial distribution of PDE also become evident when the size of the pixels of MPPCs is small, which signifies higher nonuniformity of the electric field distribution in MPPCs with small pixel size. A method is proposed for characterization of the 2D electrical field spatial distribution uniformity in a single pixel of MPPCs, which can be used for guiding the optimisation of the fabrication process of MPPCs and their properties. This promising method can naturally be extended to any Geiger avalanche photodiodes (G-APDs) and their arrays.
Energy density and spectrum of single-cycle and sub-cycle electromagnetic pulses
Authors: Artyukov I.A. , Vinogradov A.V. , D’yachkov N.V. , Feshchenko R.M. 
Published: February 2020

Abstract
Based on the exact solution of the Maxwell equations in the form of a collapsing spherical vector wave specified by an arbitrary function of time, we have calculated the maximum energy density that can be achieved when focusing extremely short pulses of various shapes. It is shown that our earlier formula expressing the maximum energy density in terms of the spectrum parameters for Gaussian quasi-monochromatic pulses is approximately (with an accuracy of ±40 %) valid for the main types of extremely short pulses.
High-power (>1 W) room-temperature quantum-cascade lasers for the long-wavelength IR region
Authors: Dudelev V.V. , Mikhailov D.A. , Babichev A.V. , Andreev A.D. , Losev S.N. , Kognovitskaya E.A. , Bobretsova Yu.K. , Slipchenko S.O. , Pikhtin N.A. , Gladyshev A.G. , Denisov D.V. , Novikov I.I. , Karachinsky L.Ya. , Kuchinskii V.I. , Egorov A.Yu. , Sokolovskii G.S. 
Published: February 2020

Abstract
Ridge quantum-cascade lasers emitting at a wavelength near 8 μm are fabricated and studied. Lasing at room temperature with a maximum output peak power exceeding 1 W from one facet is demonstrated.
Effect of elastic anisotropy on thermally induced distortions of a laser beam in single cubic syngony crystals with radial cooling. Part I
Authors: Vyatkin A.G. , Khazanov E.A. 
Published: February 2020

Abstract
We have studied thermally induced distortions of a beam in single cubic syngony crystals of all symmetry groups with an anisotropic elastic stiffness tensor. The arithmetic mean and the difference between the thermally induced phase incursions of eigenpolarisations, as well as the angle of incidence of these polarisations, are calculated for a long rod and a thin disk with radial cooling under uniform volume pumping of the active element. The position of the specific crystal orientations unrelated to its symmetry elements is investigated. The effective values of the thermo-optical constant Q in two specific orientations, as well as the thermo-optical constant P in an arbitrary orientation, are found.
Experimental and theoretical description of the process of contact laser surgery with a titanium-doped optothermal fibre converter
Authors: Belikov A.V. , Skrypnik A.V. 
Published: February 2020

Abstract
In an in vitro experiment simulating a surgeon’s actions in the process of contact laser surgery of soft biological tissue, the dependences of the temperature of a titanium-doped optothermal fibre converter (TOTFC) and the depths of coagulation and ablation of biological tissue on the average radiation power of a diode laser with a wavelength of 980 nm and on the speed of the converter movement along biological tissue are obtained. The structural, optical, and thermophysical models of TOTFC are discussed, as well as the thermophysical model of the interaction of a laser-heated converter with biological tissue, which takes into account the temperature dependences of the basic thermophysical parameters of the converter and biological tissue, as well as the contribution of the thickness h
int of the water vapour layer between the converter and biotissue. It is shown that the proposed model allows describing the result of contact laser surgery of soft biotissue with TOTFC adequately to the experiment.
Experimental studies of 1.5 – 1.6 μm high-power single-frequency semiconductor lasers
Authors: Bagaeva O.O. , Galiev R.R. , Danilov A.I. , Ivanov A.V. , Kurnosov V.D. , Kurnosov K.V. , Kurnyavko Yu.V. , Ladugin M.A. , Marmalyuk A.A. , Romantsevich V.I. , Simakov V.A. , Chernov R.V. , Shishkov V.V. 
Published: February 2020

Abstract
High-power semiconductor laser systems based on 1.5 – 1.6 μm single-frequency distributed feedback (DFB) lasers with a sidewall Bragg diffraction grating are developed and their current – voltage, light – current, and spectral characteristics are experimentally studied. The characteristics of conventional lasers with a Fabry – Perot cavity and DFB lasers fabricated from one and the same heterostructure are compared. At a pump current not exceeding 700 mA, a conventional laser with a cavity length of 1.6 mm and a mesa-stripe width of 3 μm emits a power no lower than 200 mW versus 150 mW of the DFB laser; both lasers are mounted in a housing 11 mm in diameter. The DFB laser mounted in a butterfly housing emits a power no lower than 100 mW at the exit of the single-mode cable at a pump current not exceeding 500 mA, which, at a 60 % coupling efficiency, corresponds to a power no lower than 165 mW; the side-mode suppression ratio in this case is no lower than 53 dB. It is shown that the wavelength deviation with changing pump current and temperature is almost an order of magnitude lower for the DFB laser than for the conventional laser.
Investigation of compression of indirect-drive targets under conditions of the NIF facility using one-dimensional modelling
Authors: Rozanov V.B. , Vergunova G.A. 
Published: February 2020

Abstract
The indirect compression dynamics of targets containing capsules with ablators of a plastic, high-density carbon and beryllium is simulated in the framework of a one-dimensional model based on the 1D RADIAN code. Experiments with such targets are performed on the NIF facility in the Livermore Laboratory (USA) in 2014 – 2018. The 1D simulation data are consistent with the results of experiments and calculations made at this Laboratory. The effect of the hard part of hohlraum radiation on capsule compression parameters is confirmed. We demonstrate the feasibility of eliminating this influence not only by selecting the hohlraum material but also by introducing admixtures into the capsule that absorb this radiation. It is shown how varying the amount of admixture in the capsule ablator varies the spectrum of the radiation that heats the DT fuel.