bluuebunny/crossref_metadata_2025_split huggingface dataset:
The O(1S) 297.2‐nm Dayglow Emission: A Tracer of CO2 Density Variations in the Martian Lower Thermosphere
Authors: Gkouvelis L. , Gérard J.‐C. , Ritter B. , Hubert B. , Schneider N. M. , Jain S. K. 
Published: November 2018

AbstractThe O(1S) metastable atoms can radiatively relax by emitting airglow at 557.7 and 297.2 nm. The latter one has been observed with the Imaging Ultraviolet Spectrograph onboard the Mars Atmosphere and Volatile Evolution Mars orbiter since 2014. Limb profiles of the 297.2‐nm dayglow have been collected near periapsis with a spatial resolution of 5 km or less. They show a double‐peak structure that was previously predicted but never observed during earlier Mars missions. The production of both 297.2‐nm layers is dominated by photodissociation of CO2. Their altitude and brightness is variable with season and latitude, reflecting changes in the total column of CO2 present in the lower thermosphere. Since the lower emission peak near 85 km is solely produced by photodissociation, its peak is an indicator of the unit optical depth pressure level and the overlying CO2 column density. Its intensity is directly controlled by the Lyman‐α solar flux reaching the Martian upper atmosphere. We take advantage of the Lyman‐α flux measurements of the solar Extreme Ultraviolet Monitor instrument onboard Mars Atmosphere and Volatile Evolution to model the observed OI 297.2‐nm limb profiles. For this, we combine photodissociation sources with chemical processes and photoelectron impact excitation. To determine the relative importance of the excitation processes, we apply the model to the atmospheric structure measured by the Viking 1 lander before applying it to a model atmosphere. We find very good agreement with the lower peak structure and intensity if the CO2 density provided by the Mars Climate Database is scaled down by a factor between 0.50 and 0.66. We also determine that the previously uncertain quantum yield for production of O(1S) atoms by photodissociation of CO2 at Lyman‐α wavelength is about 8%.
Advances in the Eddy Covariance Approach to CH4 Monitoring Over Two and a Half Decades
Authors: Morin Timothy H. 
Published: November 2018

AbstractReceding permafrost may expose the largest store of sequestered carbon to microbes ready to convert it to greenhouse gases. The fluxes of biogenic gases associated with boreal wetlands have historically been difficult to measure, limiting our understanding of what may happen as permafrost thaws. The many difficulties in working in high‐latitude climates have dramatically limited our understanding on the spatial and temporal distribution of fluxes and what is likely to change with a warming climate. The use of the eddy covariance approach to measure methane emissions has been developing steadily over the past 26 years. Taylor et al. (2018, https://doi.org/10.1029/2018JG004444) is an excellent example of the advancements made in the field. Here I summarize the history of the eddy covariance methane literature, describe advancements in spatial and temporal coverage, and look at important drivers of methane emissions.
miR-330-5p targets SPRY2 to promote hepatocellular carcinoma progression via MAPK/ERK signaling
Authors: Xiao Shuai , Yang Mengyuan , Yang Hao , Chang Ruimin , Fang Feng , Yang Lianyue 
Published: November 2018

AbstractMicroRNAs (miRNAs) have been identified as critical modulators of cell proliferation and growth, which are the major causes of cancer progression including hepatocellular carcinoma (HCC). Our previous miRNA microarray data have shown that miR-330-5p was always upregulated in HCC. However, the accurate role of miR-330-5p in HCC is still uncertain. Here, we report that miR-330-5p expression is upregulated in HCC tissues and cell lines, and is associated with tumor size, tumor nodule number, capsule formation and Tumor Node Metastasis (TNM) stage in HCC patients. Overexpression of miR-330-5p promotes proliferation and growth of HCC cells in vitro and in vivo, while miR-330-5p knockdown has the inverse effect. Moreover, using miRNA databases and dual luciferase report assay, we find miR-330-5p directly binds to the 3′-untranslated region (3′-UTR) of Sprouty2 (SPRY2). Then we find the novel biofunctional role of SPRY2 inactivation in promoting HCC progression. Finally, we confirm that miR-330-5p suppresses SPRY2 to promote proliferation via mitogen-activated protein kinases (MAPK)/extracellular regulated kinase (ERK) signaling in HCC. Taken together, our findings demonstrate the critical role of miR-330-5p in promoting HCC progression via targeting SPRY2 to activate MAPK/ERK signaling, which may provide a novel and promising prognostic marker and therapeutic target for HCC.
LncRNA UCA1 promotes tumor metastasis by inducing miR-203/ZEB2 axis in gastric cancer
Authors: Gong Pihai , Qiao Fengchang , Wu Huazhang , Cui He , Li Yiping , Zheng Ying , Zhou Menghan , Fan Hong 
Published: November 2018

AbstractIncreasing studies showed that long-noncoding RNAs (lncRNAs) play important roles in the biological processes, including cancer initiation and progression. However, little is known about the exact role and regulation mechanism of lncRNA UCA1 during the progression of gastric cancer (GC). In this study, we found that UCA1 was aberrantly elevated in gastric cancer tissues, and was significantly associated with lymph node metastasis and TNM stage. In vivo and in vitro, enforced UCA1 level promoted cell migration and invasion of GC cell. Depleted UCA1 expression level attenuated the ability of cell migration and invasion in GC. And then, we detected that expression level of ZEB2, a transcription factor related to tumor metastasis, was regulated by UCA1 in GC cells. miR-203 targets and suppresses to ZEB2 expression. Furthermore, we found that UCA1 could directly interact with miR-203 and lead to the release of miR-203-targeted transcripts ZEB2. Herein, we revealed the novel mechanism of UCA1 on regulating metastasis-related gene by sponge regulatory axis during GC metastasis. Our findings indicated that UCA1 plays a critical role in metastatic GC by mediating sponge regulatory axis miR-203/ZEB2. To explore function of UCA1-miR-203-ZEB2 axis may provide an informative biomarker of malignancy and a highly selective anti-GC therapeutic target.
Seasonal energy exchange in sea ice retreat regions contributes to differences in projected Arctic warming
Authors: Boeke Robyn C. , Taylor Patrick C. 
Published: November 2018

AbstractRapid and, in many cases, unprecedented Arctic climate changes are having far-reaching impacts on natural and human systems. Despite state-of-the-art climate models capturing the rapid nature of Arctic climate change, termed Arctic amplification, they significantly disagree on its magnitude. Using a regional, process-oriented surface energy budget analysis, we argue that differences in seasonal energy exchanges in sea ice retreat regions via increased absorption and storage of sunlight in summer and increased upward surface turbulent fluxes in fall/winter contribute to the inter-model spread. Models able to more widely disperse energy drawn from the surface in sea ice retreat regions warm more, suggesting that differences in the local Arctic atmospheric circulation response contribute to the inter-model spread. We find that the principle mechanisms driving the inter-model spread in Arctic amplification operate locally on regional scales, requiring an improved understanding of atmosphere-ocean-sea ice interactions in sea ice retreat regions to reduce the spread.
Dual HLA B*42 and B*81-reactive T cell receptors recognize more diverse HIV-1 Gag escape variants
Authors: Ogunshola Funsho , Anmole Gursev , Miller Rachel L. , Goering Emily , Nkosi Thandeka , Muema Daniel , Mann Jaclyn , Ismail Nasreen , Chopera Denis , Ndung’u Thumbi , Brockman Mark A. , Ndhlovu Zaza M 
Published: November 2018

AbstractSome closely related human leukocyte antigen (HLA) alleles are associated with variable clinical outcomes following HIV-1 infection despite presenting the same viral epitopes. Mechanisms underlying these differences remain unclear but may be due to intrinsic characteristics of the HLA alleles or responding T cell repertoires. Here we examine CD8+T cell responses against the immunodominant HIV-1 Gag epitope TL9 (TPQDLNTML180–188) in the context of the protective allele B*81:01 and the less protective allele B*42:01. We observe a population of dual-reactive T cells that recognize TL9 presented by both B*81:01 and B*42:01 in individuals lacking one allele. The presence of dual-reactive T cells is associated with lower plasma viremia, suggesting a clinical benefit. In B*42:01 expressing individuals, the dual-reactive phenotype defines public T cell receptor (TCR) clones that recognize a wider range of TL9 escape variants, consistent with enhanced control of viral infection through containment of HIV-1 sequence adaptation.
A CRISPR–Cas9-triggered strand displacement amplification method for ultrasensitive DNA detection
Authors: Zhou Wenhua , Hu Li , Ying Liming , Zhao Zhen , Chu Paul K. , Yu Xue-Feng 
Published: November 2018

AbstractAlthough polymerase chain reaction (PCR) is the most widely used method for DNA amplification, the requirement of thermocycling limits its non-laboratory applications. Isothermal DNA amplification techniques are hence valuable for on-site diagnostic applications in place of traditional PCR. Here we describe a true isothermal approach for amplifying and detecting double-stranded DNA based on a CRISPR–Cas9-triggered nicking endonuclease-mediated Strand Displacement Amplification method (namely CRISDA). CRISDA takes advantage of the high sensitivity/specificity and unique conformational rearrangements of CRISPR effectors in recognizing the target DNA. In combination with a peptide nucleic acid (PNA) invasion-mediated endpoint measurement, the method exhibits attomolar sensitivity and single-nucleotide specificity in detection of various DNA targets under a complex sample background. Additionally, by integrating the technique with a Cas9-mediated target enrichment approach, CRISDA exhibits sub-attomolar sensitivity. In summary, CRISDA is a powerful isothermal tool for ultrasensitive and specific detection of nucleic acids in point-of-care diagnostics and field analyses.
Slx5-Slx8 ubiquitin ligase targets active pools of the Yen1 nuclease to limit crossover formation
Authors: Talhaoui Ibtissam , Bernal Manuel , Mullen Janet R. , Dorison Hugo , Palancade Benoit , Brill Steven J. , Mazón Gerard 
Published: November 2018

AbstractThe repair of double-stranded DNA breaks (DSBs) by homologous recombination involves the formation of branched intermediates that can lead to crossovers following nucleolytic resolution. The nucleases Mus81-Mms4 and Yen1 are tightly controlled during the cell cycle to limit the extent of crossover formation and preserve genome integrity. Here we show that Yen1 is further regulated by sumoylation and ubiquitination. In vivo, Yen1 becomes sumoylated under conditions of DNA damage by the redundant activities of Siz1 and Siz2 SUMO ligases. Yen1 is also a substrate of the Slx5-Slx8 ubiquitin ligase. Loss of Slx5-Slx8 stabilizes the sumoylated fraction, attenuates Yen1 degradation at the G1/S transition, and results in persistent localization of Yen1 in nuclear foci. Slx5-Slx8-dependent ubiquitination of Yen1 occurs mainly at K714 and mutation of this lysine increases crossover formation during DSB repair and suppresses chromosome segregation defects in a mus81∆ background.
Colossal tunability in high frequency magnetoelectric voltage tunable inductors
Authors: Yan Yongke , Geng Liwei D. , Tan Yaohua , Ma Jianhua , Zhang Lujie , Sanghadasa Mohan , Ngo Khai , Ghosh Avik W. , Wang Yu U. , Priya Shashank 
Published: November 2018

AbstractThe electrical modulation of magnetization through the magnetoelectric effect provides a great opportunity for developing a new generation of tunable electrical components. Magnetoelectric voltage tunable inductors (VTIs) are designed to maximize the electric field control of permeability. In order to meet the need for power electronics, VTIs operating at high frequency with large tunability and low loss are required. Here we demonstrate magnetoelectric VTIs that exhibit remarkable high inductance tunability of over 750% up to 10 MHz, completely covering the frequency range of state-of-the-art power electronics. This breakthrough is achieved based on a concept of magnetocrystalline anisotropy (MCA) cancellation, predicted in a solid solution of nickel ferrite and cobalt ferrite through first-principles calculations. Phase field model simulations are employed to observe the domain-level strain-mediated coupling between magnetization and polarization. The model reveals small MCA facilitates the magnetic domain rotation, resulting in larger permeability sensitivity and inductance tunability.
Efficient solar-driven electrocatalytic CO2 reduction in a redox-medium-assisted system
Authors: Wang Yuhang , Liu Junlang , Wang Yifei , Wang Yonggang , Zheng Gengfeng 
Published: November 2018

AbstractSolar-driven electrochemical carbon dioxide (CO2) reduction is capable of producing value-added chemicals and represents a potential route to alleviate carbon footprint in the global environment. However, the ever-changing sunlight illumination presents a substantial impediment of maintaining high electrocatalytic efficiency and stability for practical applications. Inspired by green plant photosynthesis with separate light reaction and (dark) carbon fixation steps, herein, we developed a redox-medium-assisted system that proceeds water oxidation with a nickel-iron hydroxide electrode under light illumination and stores the reduction energy using a zinc/zincate redox, which can be controllably released to spontaneously reduce CO2 into carbon monoxide (CO) with a gold nanocatalyst in dark condition. This redox-medium-assisted system enables a record-high solar-to-CO photoconversion efficiency of 15.6% under 1-sun intensity, and an outstanding electric energy efficiency of 63%. Furthermore, it allows a unique tuning capability of the solar-to-CO efficiency and selectivity by the current density applied during the carbon fixation.
MFF-dependent mitochondrial fission regulates presynaptic release and axon branching by limiting axonal mitochondria size
Authors: Lewis Tommy L. , Kwon Seok-Kyu , Lee Annie , Shaw Reuben , Polleux Franck 
Published: November 2018

AbstractNeurons display extreme degrees of polarization, including compartment-specific organelle morphology. In cortical, long-range projecting, pyramidal neurons (PNs), dendritic mitochondria are long and tubular whereas axonal mitochondria display uniformly short length. Here we explored the functional significance of maintaining small mitochondria for axonal development in vitro and in vivo. We report that the Drp1 ‘receptor’ Mitochondrial fission factor (MFF) is required for determining the size of mitochondria entering the axon and then for maintenance of their size along the distal portions of the axon without affecting their trafficking properties, presynaptic capture, membrane potential or ability to generate ATP. Strikingly, this increase in presynaptic mitochondrial size upon MFF downregulation augments their capacity for Ca2+ ([Ca2+]m) uptake during neurotransmission, leading to reduced presynaptic [Ca2+]c accumulation, decreased presynaptic release and terminal axon branching. Our results uncover a novel mechanism controlling neurotransmitter release and axon branching through fission-dependent regulation of presynaptic mitochondrial size.
Human milk oligosaccharides, milk microbiome and infant gut microbiome modulate neonatal rotavirus infection
Authors: Ramani Sasirekha , Stewart Christopher J. , Laucirica Daniel R. , Ajami Nadim J. , Robertson Bianca , Autran Chloe A. , Shinge Dhairyasheel , Rani Sandya , Anandan Sasirekha , Hu Liya , Ferreon Josephine C. , Kuruvilla Kurien A. , Petrosino Joseph F. , Venkataram Prasad B. V. , Bode Lars , Kang Gagandeep , Estes Mary K. 
Published: November 2018

AbstractNeonatal rotavirus infections are predominantly asymptomatic. While an association with gastrointestinal symptoms has been described in some settings, factors influencing differences in clinical presentation are not well understood. Using multidisciplinary approaches, we show that a complex interplay between human milk oligosaccharides (HMOs), milk microbiome, and infant gut microbiome impacts neonatal rotavirus infections. Validating in vitro studies where HMOs are not decoy receptors for neonatal strain G10P[11], population studies show significantly higher levels of Lacto-N-tetraose (LNT), 2’-fucosyllactose (2’FL), and 6’-siallylactose (6’SL) in milk from mothers of rotavirus-positive neonates with gastrointestinal symptoms. Further, these HMOs correlate with abundance ofEnterobacter/Klebsiellain maternal milk and infant stool. Specific HMOs also improve the infectivity of a neonatal strain-derived rotavirus vaccine. This study provides molecular and translational insight into host factors influencing neonatal rotavirus infections and identifies maternal components that could promote the performance of live, attenuated rotavirus vaccines.
Spin decoherence in a two-qubit CPHASE gate: the critical role of tunneling noise
Authors: Huang Peihao , Zimmerman Neil M. , Bryant Garnett W. 
Published: November 2018

AbstractRapid progress in semiconductor spin qubits has enabled experimental demonstrations of a two-qubit logic gate. Understanding spin decoherence in a two-qubit logic gate is necessary for optimal qubit operation. We study spin decoherence due to 1/f charge noise for two electrons in a double quantum dot used for a two-qubit controlled-phase gate. In contrast to the usual belief, spin decoherence can be dominated by the tunneling noise from 1/f charge noise instead of the detuning noise. Tunneling noise can dominate because the effect of tunneling noise on the spin qubit is first order in the charge admixture; while the effect of the detuning noise is only second order. The different orders of contributions result in different detuning dependence of the decoherence, which provides a way to identify the noise source. We find that decoherence in a recent two-qubit experiment was dominated by the tunneling noise from 1/f charge noise. The results illustrate the importance of considering tunneling noise to design optimal operation of spin qubits.
Pre-clinical evaluation of a P. berghei-based whole-sporozoite malaria vaccine candidate
Authors: Mendes António M. , Reuling Isaie J. , Andrade Carolina M. , Otto Thomas D. , Machado Marta , Teixeira Filipa , Pissarra Joana , Gonçalves-Rosa Nataniel , Bonaparte Dolores , Sinfrónio João , Sanders Mandy , Janse Chris J. , Khan Shahid M. , Newbold Chris I. , Berriman Matthew , Lee Cynthia K. , Wu Yimin , Ockenhouse Christian F. , Sauerwein Robert W. , Prudêncio Miguel 
Published: November 2018

AbstractWhole-sporozoite vaccination/immunization induces high levels of protective immunity in both rodent models of malaria and in humans. Recently, we generated a transgenic line of the rodent malaria parasiteP. berghei(Pb) that expresses theP. falciparum(Pf) circumsporozoite protein (PfCS), and showed that this parasite line (PbVac) was capable of (1) infecting and developing in human hepatocytes but not in human erythrocytes, and (2) inducing neutralizing antibodies against the humanPfparasite. Here, we analyzedPbVac in detail and developed tools necessary for its use in clinical studies. A microbiological contaminant-free Master Cell Bank ofPbVac parasites was generated through a process of cyclic propagation and clonal expansion in mice and mosquitoes and was genetically characterized. A highly sensitive qRT-PCR-based method was established that enablesPbVac parasite detection and quantification at low parasite densities in vivo. This method was employed in a biodistribution study in a rabbit model, revealing that the parasite is only present at the site of administration and in the liver up to 48 h post infection and is no longer detectable at any site 10 days after administration. An extensive toxicology investigation carried out in rabbits further showed the absence ofPbVac-related toxicity. In vivo drug sensitivity assays employing rodent models of infection showed that both the liver and the blood stage forms ofPbVac were completely eliminated by Malarone®treatment. Collectively, our pre-clinical safety assessment demonstrates thatPbVac possesses all characteristics necessary to advance into clinical evaluation.
Multiple physical aspects during the flow and heat transfer analysis of Carreau fluid with nanoparticles
Authors: Hashim  , Hafeez Abdul , Alshomrani Ali Saleh , Khan Masood 
Published: November 2018

AbstractThe current work is concerned with the two-dimensional boundary layer flow of a non-Newtonian fluid in the presence of nanoparticles. The heat and mass transfer mechanism for Carreau nanofluid flow due to a radially stretching/shrinking sheet is further investigated in this article. The governing physical situation is modelled in the form of partial differential equations and are simplified to a system of non-linear ordinary differential equations by employing dimensionless variables. Numerical simulations for non-dimensional velocity, temperature and concentration fields has been performed with the assistance of built-in Matlab solver bvp4c routine. One significant computational outcome of this study is the existence of multiple numerical solutions for the flow fields. The impacts of various developing parameters, for instance, Weissenberg number, power-law index, shrinking parameter, suction parameter, Prandtl number, Schmidt number, Brownian motion and thermophoresis parameter on the velocity, temperature and nanoparticles concentration are visualized through tables and graphical experiment. The numerical results demonstrate that the rates of heat and mass transfer are raised by higher Weissenberg number for first solution and an inverse is seen for second solution. Moreover, an increasing trend is seen in nanofluids temperature for both solutions with greater values of thermophoresis parameter. In addition, the numerical results obtained by the applied technique are validated with existing literature and found to be in an excellent agreement.
Phylogenetic and mutational analyses of human LEUTX, a homeobox gene implicated in embryogenesis
Authors: Katayama Shintaro , Ranga Vipin , Jouhilahti Eeva-Mari , Airenne Tomi T. , Johnson Mark S. , Mukherjee Krishanu , Bürglin Thomas R. , Kere Juha 
Published: November 2018

AbstractRecently, human PAIRED-LIKE homeobox transcription factor (TF) genes were discovered whose expression is limited to the period of embryo genome activation up to the 8-cell stage. One of these TFs is LEUTX, but its importance for human embryogenesis is still subject to debate. We confirmed that human LEUTX acts as a TAATCC-targeting transcriptional activator, like other K50-type PAIRED-LIKE TFs. Phylogenetic comparisons revealed that Leutx proteins are conserved across Placentalia and comprise two conserved domains, the homeodomain, and a Leutx-specific domain containing putative transcriptional activation motifs (9aaTAD). Examination of human genotype resources revealed 116 allelic variants in LEUTX. Twenty-four variants potentially affect function, but they occur only heterozygously at low frequency. One variant affects a DNA-specificity determining residue, mutationally reachable by a one-base transition. In vitro and in silico experiments showed that this LEUTX mutation (alanine to valine at position 54 in the homeodomain) results in a transactivational loss-of-function to a minimal TAATCC-containing promoter and a 36 bp motif enriched in genes involved in embryo genome activation. A compensatory change in residue 47 restores function. The results support the notion that human LEUTX functions as a transcriptional activator important for human embryogenesis.