bluuebunny/crossref_metadata_2025 huggingface dataset:
Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). III. Star formation properties of the host galaxies at z ≳ 6 studied with ALMA
Authors: Izumi Takuma , Onoue Masafusa , Shirakata Hikari , Nagao Tohru , Kohno Kotaro , Matsuoka Yoshiki , Imanishi Masatoshi , Strauss Michael A , Kashikawa Nobunari , Schulze Andreas , Silverman John D , Fujimoto Seiji , Harikane Yuichi , Toba Yoshiki , Umehata Hideki , Nakanishi Kouichiro , Greene Jenny E , Tamura Yoichi , Taniguchi Akio , Yamaguchi Yuki , Goto Tomotsugu , Hashimoto Yasuhiro , Ikarashi Soh , Iono Daisuke , Iwasawa Kazushi , Lee Chien-Hsiu , Makiya Ryu , Minezaki Takeo , Tang Ji-Jia
Published: February 2018

We present our ALMA Cycle 4 measurements of the [C ii] emission line and the underlying far-infrared (FIR) continuum emission from four optically low-luminosity (M1450 > −25) quasars at z ≳ 6 discovered by the Subaru Hyper Suprime Cam (HSC) survey. The [C ii] line and FIR continuum luminosities lie in the ranges $L_{\rm [C\,{\small {II}}]} = (3.8\mbox{--}10.2)\times 10^{8}\,L_{\odot }$ and LFIR = (1.2–2.0) × 1011 L$_{\odot}$, which are at least one order of magnitude smaller than those of optically-luminous quasars at z ≳ 6. We estimate the star formation rates (SFRs) of our targets as ≃ 23–40 M$_{\odot}$ yr−1. Their line and continuum-emitting regions are marginally resolved, and found to be comparable in size to those of optically-luminous quasars, indicating that their SFR or likely gas mass surface densities (key controlling parameter of mass accretion) are accordingly different. The $L_{\rm [C\,{\small {II}}]}/L_{\rm FIR}$ ratios of the hosts, ≃ (2.2–8.7) × 10−3, are fully consistent with local star-forming galaxies. Using the [C ii] dynamics, we derived their dynamical masses within a radius of 1.5–2.5 kpc as ≃ (1.4–8.2) × 1010 M$_{\odot}$. By interpreting these masses as stellar ones, we suggest that these faint quasar hosts are on or even below the star-forming main sequence at z ∼ 6, i.e., they appear to be transforming into quiescent galaxies. This is in contrast to the optically-luminous quasars at those redshifts, which show starburst-like properties. Finally, we find that the ratios of black hole mass to host galaxy dynamical mass of most of the low-luminosity quasars, including the HSC ones, are consistent with the local value. The mass ratios of the HSC quasars can be reproduced by a semi-analytical model that assumes merger-induced black hole host galaxy evolution.
Regulation of Hydroxycinnamic Acid Degradation DrivesAgrobacterium fabrumLifestyles
Authors: Meyer Thibault , Renoud Sébastien , Vigouroux Armelle , Miomandre Aurélie , Gaillard Vincent , Kerzaon Isabelle , Prigent-Combaret Claire , Comte Gilles , Moréra Solange , Vial Ludovic , Lavire Céline
Published: February 2018

Regulatory factors are key components for the transition between different lifestyles to ensure rapid and appropriate gene expression upon perceiving environmental cues. Agrobacterium fabrum C58 (formerly called A. tumefaciens C58) has two contrasting lifestyles: it can interact with plants as either a rhizosphere inhabitant (rhizospheric lifestyle) or a pathogen that creates its own ecological niche in a plant tumor via its tumor-inducing plasmid (pathogenic lifestyle). Hydroxycinnamic acids are known to play an important role in the pathogenic lifestyle of Agrobacterium spp. but can be degraded in A. fabrum species. We investigated the molecular and ecological mechanisms involved in the regulation of A. fabrum species-specific genes responsible for hydroxycinnamic acid degradation. We characterized the effectors (feruloyl-CoA and p-coumaroyl-CoA) and the DNA targets of the MarR transcriptional repressor, which we named HcaR, which regulates hydroxycinnamic acid degradation. Using an hcaR-deleted strain, we further revealed that hydroxycinnamic acid degradation interfere with virulence gene expression. The HcaR deletion mutant shows a contrasting competitive colonization ability, being less abundant than the wild-type strain in tumors but more abundant in the rhizosphere. This supports the view that A. fabrum C58 HcaR regulation through ferulic and p-coumaric acid perception is important for the transition between lifestyles.
Prospects for comparison of matter and antimatter gravitation with ALPHA-g
Authors: Bertsche W. A.
Published: February 2018

The ALPHA experiment has recently entered an expansion phase of its experimental programme, driven in part by the expected benefits of conducting experiments in the framework of the new AD + ELENA antiproton facility at CERN. With antihydrogen trapping now a routine operation in the ALPHA experiment, the collaboration is leading progress towards precision atomic measurements on trapped antihydrogen atoms, with the first excitation of the 1S–2S transition and the first measurement of the antihydrogen hyperfine spectrum (Ahmadi
et al.
2017
Nature
541
, 506–510 (
doi:10.1038/nature21040
);
Nature
548
, 66–69 (
doi:10.1038/nature23446
)). We are building on these successes to extend our physics programme to include a measurement of antimatter gravitation. We plan to expand a proof-of-principle method (Amole
et al.
2013
Nat. Commun.
4
, 1785 (
doi:10.1038/ncomms2787
)), first demonstrated in the original ALPHA apparatus, and perform a precise measurement of antimatter gravitational acceleration with the aim of achieving a test of the weak equivalence principle at the 1% level. The design of this apparatus has drawn from a growing body of experience on the simulation and verification of antihydrogen orbits confined within magnetic-minimum atom traps. The new experiment, ALPHA-g, will be an additional atom-trapping apparatus located at the ALPHA experiment with the intention of measuring antihydrogen gravitation.

This article is part of the Theo Murphy meeting issue ‘Antiproton physics in the ELENA era’.
The ASACUSA antihydrogen and hydrogen program: results and prospects
Authors: Malbrunot C. , Amsler C. , Arguedas Cuendis S. , Breuker H. , Dupre P. , Fleck M. , Higaki H. , Kanai Y. , Kolbinger B. , Kuroda N. , Leali M. , Mäckel V. , Mascagna V. , Massiczek O. , Matsuda Y. , Nagata Y. , Simon M. C. , Spitzer H. , Tajima M. , Ulmer S. , Venturelli L. , Widmann E. , Wiesinger M. , Yamazaki Y. , Zmeskal J.
Published: February 2018

The goal of the ASACUSA-CUSP collaboration at the Antiproton Decelerator of CERN is to measure the ground-state hyperfine splitting of antihydrogen using an atomic spectroscopy beamline. A milestone was achieved in 2012 through the detection of 80 antihydrogen atoms 2.7 m away from their production region. This was the first observation of ‘cold’ antihydrogen in a magnetic field free region. In parallel to the progress on the antihydrogen production, the spectroscopy beamline was tested with a source of hydrogen. This led to a measurement at a relative precision of 2.7×10
−9
which constitutes the most precise measurement of the hydrogen hyperfine splitting in a beam. Further measurements with an upgraded hydrogen apparatus are motivated by CPT and Lorentz violation tests in the framework of the Standard Model Extension. Unlike for hydrogen, the antihydrogen experiment is complicated by the difficulty of synthesizing enough cold antiatoms in the ground state. The first antihydrogen quantum states scan at the entrance of the spectroscopy apparatus was realized in 2016 and is presented here. The prospects for a ppm measurement are also discussed.

This article is part of the Theo Murphy meeting issue ‘Antiproton physics in the ELENA era’.
AEgIS at ELENA: outlook for physics with a pulsed cold antihydrogen beam
Authors: Doser M. , Aghion S. , Amsler C. , Bonomi G. , Brusa R. S. , Caccia M. , Caravita R. , Castelli F. , Cerchiari G. , Comparat D. , Consolati G. , Demetrio A. , Di Noto L. , Evans C. , Fanì M. , Ferragut R. , Fesel J. , Fontana A. , Gerber S. , Giammarchi M. , Gligorova A. , Guatieri F. , Haider S. , Hinterberger A. , Holmestad H. , Kellerbauer A. , Khalidova O. , Krasnický D. , Lagomarsino V. , Lansonneur P. , Lebrun P. , Malbrunot C. , Mariazzi S. , Marton J. , Matveev V. , Mazzotta Z. , Müller S. R. , Nebbia G. , Nedelec P. , Oberthaler M. , Pacifico N. , Pagano D. , Penasa L. , Petracek V. , Prelz F. , Prevedelli M. , Rienaecker B. , Robert J. , Røhne O. M. , Rotondi A. , Sandaker H. , Santoro R. , Smestad L. , Sorrentino F. , Testera G. , Tietje I. C. , Widmann E. , Yzombard P. , Zimmer C. , Zmeskal J. , Zurlo N.
Published: February 2018

The efficient production of cold antihydrogen atoms in particle traps at CERN’s Antiproton Decelerator has opened up the possibility of performing direct measurements of the Earth’s gravitational acceleration on purely antimatter bodies. The goal of the AEgIS collaboration is to measure the value of
g
for antimatter using a pulsed source of cold antihydrogen and a Moiré deflectometer/Talbot–Lau interferometer. The same antihydrogen beam is also very well suited to measuring precisely the ground-state hyperfine splitting of the anti-atom. The antihydrogen formation mechanism chosen by AEgIS is resonant charge exchange between cold antiprotons and Rydberg positronium. A series of technical developments regarding positrons and positronium (Ps formation in a dedicated room-temperature target, spectroscopy of the
n
=1–3 and
n
=3–15 transitions in Ps, Ps formation in a target at 10 K inside the 1 T magnetic field of the experiment) as well as antiprotons (high-efficiency trapping of

, radial compression to sub-millimetre radii of mixed

plasmas in 1 T field, high-efficiency transfer of

to the antihydrogen production trap using an in-flight launch and recapture procedure) were successfully implemented. Two further critical steps that are germane mainly to charge exchange formation of antihydrogen—cooling of antiprotons and formation of a beam of antihydrogen—are being addressed in parallel. The coming of ELENA will allow, in the very near future, the number of trappable antiprotons to be increased by more than a factor of 50. For the antihydrogen production scheme chosen by AEgIS, this will be reflected in a corresponding increase of produced antihydrogen atoms, leading to a significant reduction of measurement times and providing a path towards high-precision measurements.

This article is part of the Theo Murphy meeting issue ‘Antiproton physics in the ELENA era’.
QsRNA-seq: a method for high-throughput profiling and quantifying small RNAs
Authors: Fishman Alla , Light Dean , Lamm Ayelet T.
Published: February 2018

The finding that small non-coding RNAs (sRNAs) can affect cellular processes by regulating gene expression had a significant impact on biological research and clinical diagnosis. Yet, the ability to quantify and profile sRNAs, specifically miRNAs, using high-throughput sequencing is especially challenging because of their small size and repetitive nature. We developed QsRNA-seq, a method for preparation of sRNA libraries for high-throughput sequencing that overcomes this difficulty by enabling separation of fragments shorter than 100nt long that differ only by 20nt in length. The method supports using unique molecular identifiers for quantification. We show that QsRNA-seq gives very accurate, comprehensive and reproducible results. Using QsRNA-seq to study the miRNA repertoire inC. elegansembryo and L4 larval developmental stages, enabled extending the list of miRNAs that are expressed in a developmental-specific manner. Interestingly, we found that miRNAs 23nt long are predominantly expressed in developmental stage L4, suggesting a possible connection between the length of miRNA and its developmental role.
A genome-wide miRNA screen identifies regulators of tetraploid cell proliferation
Authors: Vittoria Marc A. , Shenk Elizabeth M. , O’Rourke Kevin P. , Bolgioni Amanda F. , Lim Sanghee , Kacprzak Victoria , Quinton Ryan J. , Ganem Neil J.
Published: February 2018

Tetraploid cells, which are most commonly generated by errors in cell division, are genomically unstable and have been shown to promote tumorigenesis. Recent genomic studies have estimated that ∼40% of all solid tumors have undergone a genome-doubling event during their evolution, suggesting a significant role for tetraploidy in driving the development of human cancers. To safeguard against the deleterious effects of tetraploidy, non-transformed cells that fail mitosis and become tetraploid activate both the Hippo and p53 tumor suppressor pathways to restrain further proliferation. Tetraploid cells must therefore overcome these anti-proliferative barriers to ultimately drive tumor development. However, the genetic routes through which spontaneously arising tetraploid cells adapt to regain proliferative capacity remain poorly characterized. Here, we conducted a comprehensive, gain-of-function genome-wide screen to identify miRNAs that are sufficient to promote the proliferation of tetraploid cells. Our screen identified 23 miRNAs whose overexpression significantly promotes tetraploid proliferation. The vast majority of these miRNAs facilitate tetraploid growth by enhancing mitogenic signaling pathways (e.g. miR-191-3p); however, we also identified several miRNAs that impair the p53/p21 pathway (e.g. miR-523-3p), and a single miRNA (miR-24-3p) that potently inactivates the Hippo pathway via downregulation of the tumor suppressor gene NF2. Collectively, our data reveal several avenues through which tetraploid cells may regain the proliferative capacity necessary to drive tumorigenesis.
Binding of General Anesthetics to Ion Channels
Authors: Stock Letícia , Hosoume Juliana , Cirqueira Leonardo , Treptow Werner
Published: February 2018

The direct-site hypothesis assumes general anesthetics bind ion channels to impact protein equilibrium and function, inducing anesthesia. Despite advancements in the field, a first-principle all-atom demonstration of this structure-function premise misses. We focus on clinically used sevoflurane interaction to anesthetic-sensitive Kv1.2 mammalian channel to resolve if sevoflurane binds the protein’s well-characterized open and closed structures in a conformation-dependent manner to shift channel equilibrium. We employ an innovative approach relying on extensive docking calculations and free-energy perturbation and find sevoflurane binds open and closed structures at multiple sites under complex saturation and concentration effects. Results point to a non-trivial interplay of conformation-dependent modes of action involving distinct binding sites that increase channel open-probability at diluted ligand concentrations. Given the challenge in exploring more complex processes potentially impacting channel-anesthetic interaction, the result is reassuring as demonstrates that the process of multiple binding events alone may account for open-probability shifts recorded in measurements.
Familial hypercholesterolemia: a single-nucleotide variant (SNV) in mosaic at the Low density lipoprotein receptor (LDLR)
Authors: Rodríguez-Nóvoa Sonia , Alonso Concepción , Rodríguez-Jiménez Carmen , Rodriguez-Laguna Lara , Gordo Gema , Martinez-Glez Victor , García Polo Iluminada
Published: February 2018

Introduction

Familial hypercholesterolemia (FH) is most frequently caused by genetic variants in the LDLR gene. Most of LDLR pathogenic variants are missense, followed by splicing and deletion/insertions variants. Mosaicism is a genetic condition in which an individual shows more than one clone of cells with different genotypes.

Objective

Molecular characterization of a patient with hypercholesterolemia.

Methods

Genetic analysis of DNA from peripheral blood and saliva was performed by NGS, sanger sequencing and pyrosequencing technologies.

Results

NGS analysis detected the pathogenic variant LDLR:c.1951G>T:p.(Asp651Tyr) in 9%-12% of reads. The presence of the variant was confirmed by pyrosequencing analysis.

Conclusion

Herein, we report the first case of a mosaic single nucleotide variant affecting the LDLR gene in a patient with familial hypercholesterolemia. As has been described for other pathologies, mosaicism could be underestimated in FH and its detection will improve with the introduction of NGS technologies in the diagnostic routine.
Tau seeding activity anticipates phospho-tau pathology in Alzheimer’s disease
Authors: Kaufman Sarah K. , Del Tredici Kelly , Thomas Talitha L. , Braak Heiko , Diamond Marc I.
Published: February 2018

Alzheimer’s disease (AD) is characterized by accumulation of tau neurofibrillary tangles (NFTs) and, according to the prion model, transcellular propagation of pathological “seeds” may underlie its progression. Staging of NFT pathology with phospho-tau antibody is useful to classify AD and primary age-related tauopathy (PART) cases. The locus coeruleus (LC) shows the earliest phospho-tau signal, whereas other studies suggest that pathology begins in the transentorhinal/entorhinal cortices (TRE/EC). The relationship of tau seeding activity, phospho-tau pathology, and progression of neurodegeneration remains obscure. Consequently, we employed an established cellular biosensor assay to quantify tau seeding activity in fixed human tissue, in parallel with AT8 phospho-tau staining of immediately adjacent sections. We studied four brain regions from each of n=247 individuals across a range of disease stages. We detected the earliest and most robust seeding activity in the TRE/EC. The LC did not uniformly exhibit seeding activity until later NFT stages. We also detected seeding activity in the first temporal gyrus and visual cortex at stages before NFTs and/or AT8-immunopositivity were detectable. AD and putative PART cases exhibited similar patterns of seeding activity that anticipated histopathology across all NFT stages. Our findings are consistent with the prion model and suggest that pathological seeding activity begins in the TRE/EC rather than in the LC, and may offer an important addition to classical histopathology.
ALOXE3 is a hepatic fasting-responsive lipoxygenase that enhances insulin sensitivity via hepatic PPARγ
Authors: Higgins Cassandra B. , Zhang Yiming , Mayer Allyson L. , Fujiwara Hideji , Stothard Alicyn I. , Graham Mark J. , Swarts Benjamin M. , DeBosch Brian J.
Published: February 2018

ABSTARCT

The hepatic glucose fasting response is gaining traction as a therapeutic pathway to enhance hepatic and whole-host metabolism. However, the mechanisms underlying these metabolic effects remain unclear. Here, we demonstrate the lipoxygenase, ALOXE3, is a novel effector of the thepatic fasting response. We show that ALOXE3 is activated during fasting, glucose withdrawal, and trehalose/trehalose analogue treatment. Hepatocyte-specific ALOXE3 expression reduced weight gain and hepatic steatosis in dietaryand genetically obese (db/db) models. ALOXE3 expression moreover enhanced basal thermogenesis and abrogated insulin resistance in db/db diabetic mice. Targeted metabolomics demonstrated accumulation of the PPARγ ligand, 12-KETE in hepatocytes overexpressing ALOXE3. Strikingly, PPARγ inhibition reversed hepatic ALOXE3-mediated insulin sensitization, suppression of hepatocellular ATP production and oxygen consumption, and gene induction of PPARγ coactivator-1a (PGC1α) expression. Moreover, hepatocyte-specific PPARγ deletion reversed the therapeutic effect of hepatic ALOXE3 expression on diet-induced insulin intolerance. ALOXE3 is therefore a novel effector of the hepatocellular fasting response that leverages both PPARγ-mediated and pleiotropic effects to augment hepatic and whole-host metabolism, and is thus a promising target to ameliorate metabolic disease.
Spatial contextual cueing is not a limiting factor for expert performance in the domain of team sports or action video game playing
Authors: Schmidt Anne , Geringswald Franziska , Pollmann Stefan
Published: February 2018

We investigated in two experiments if handball and action video game players show improved implicit learning of repeated spatial configurations for efficient search guidance in comparison to a control group without sport or video game proficiency. To this end, we used both a sport-specific pseudo 3-D contextual cueing task and the original contextual cueing paradigm (Chun & Jiang, 1998). Contextual cueing was present in all groups. However, handball and action video game players did not differ in the strength of contextual cueing from the control group. Action video game players had shorter search times than controls in both experiments. In contrast, the handball players searched faster than controls in the sport-specific displays of Experiment 1 but not in the symbolic search task of Experiment 2. Thus, our findings provide no evidence that contextual cueing is a limiting factor for expert performance in the domain of team sports or action video game playing.
Live single molecule microscopy of HIV-1 assembly in host T cells reveals a spatio-temporal effect of the viral genome
Authors: Floderer Charlotte , Masson Jean-Baptiste , Boiley Elise , Georgeault Sonia , Merida Peggy , El Beheiry Mohamed , Dahan Maxime , Roigeard Philippe , Sibarita Jean-Baptiste , Favard Cyril , Muriaux Delphine
Published: February 2018

Monitoring virus assembly dynamic at the nanoscale level in host cells remains a major challenge. Human Immunodeficiency Virus type 1 (HIV-1) components are addressed to the plasma membrane where they assemble to form spherical particles of 100nm in diameter. HIV-1 Gag protein expression alone is sufficient to produce virus-like particles (VLPs) that resemble immature virus. Here, we monitored Gag assembly in host CD4 T lymphocytes using single molecule dynamics microscopy and energy mapping. A workflow allowing long time recordings of single Gag molecule localization, diffusion and effective energy maps was developed for robust quantitative analysis of HIV assembly and budding. Comparison of numerous cell plasma membrane assembling platforms in cells expressing wild type or assembly-defective Gag proteins showed that VLP formation last 15 minutes, with an assembly time of 5 minutes, and that the nucleocapsid domain is mandatory. Importantly, it reveals that the viral genome coordinates spatio-temporally HIV-1 assembly.
Incomplete reprogramming of cell-specific epigenetic marks during asexual reproduction leads to heritable phenotypic variation in plants
Authors: Wibowo Anjar , Becker Claude , Durr Julius , Price Jonathan , Spaepen Stijn , Hilton Sally , Putra Hadi , Papareddy Ranjith , Saintain Quentin , Harvey Sarah , Bending Gary D. , Schulze-Lefert Paul , Weigel Detlef , Gutierrez-Marcos Jose
Published: February 2018

Plants differ from animals in their capability to easily regenerate fertile adult individuals from terminally differentiated cells [1]. This unique developmental plasticity is commonly observed in nature where many species can reproduce asexually through the ectopic initiation of organogenic or embryogenic developmental programs [2, 3]. However, it is not currently known if this developmental reprogramming is coupled to a global epigenomic resetting, or what impact it has on the phenotype of the clonal progeny. Here we show that plants asexually propagated via induction of a zygotic developmental program do not fully reset cell-specific epigenetic imprints. These imprints are instead inherited even over multiple rounds of sexual reproduction, becoming fixed in hybrids and resulting in heritable molecular and physiological phenotypes that depend on the founder cell used. Our results demonstrate how novel phenotypic variation in plants can be unlocked through the incomplete reprogramming of cell-specific epigenetic marks during asexual propagation.
Tectal stem cells display diverse regenerative capacities
Authors: Lindsey Benjamin W. , Aitken Georgia E. , Tang Jean K. , Khabooshan Mitra , Vandestadt Celia , Kaslin Jan
Published: February 2018

How diverse adult stem and progenitor populations regenerate tissue following damage to the CNS remains unknown across most neurogenic domains. To understand the role of quiescent radial-glial (qRG) stem cells during regeneration, we tested the hypothesis that qRG could be induced to proliferate and produce newborn neurons. We designed a stab lesion assay in the midbrain tectum of the adult zebrafish to target an isolated population of qRG, and investigated their proliferative behaviour, differentiation potential, and requirement of Wnt/β-catenin signalling for the regenerative response. EdU-labelling showed that a small proportion of qRG transit to a proliferative state (pRG), but that progeny of pRG are restricted to a radial-glial fate. Lesion promoted upregulation of proliferation and neurogenesis from neuro-epithelial-like amplifying progenitors (NE-Ap) of the tectal marginal zone (TMZ). Homeostatic levels of Wnt/β-catenin signalling persisted under lesioned conditions in the qRG/pRG population, whereby increased β-catenin staining and axin2 expression was present in the NE-Ap progenitor zone. Attenuation of Wnt signalling using Dickkopf-1, demonstrated that proliferative responses post-injury appeared to be Wnt-independent. Our results align with the emerging view that adult stem/progenitor phenotypes are characterized by discrete, rather than mutual, regenerative programs and that different stem cell domains employ different modes of regeneration.
Stable between-subject statistical inference from unstable within-subject functional connectivity estimates
Authors: Vidaurre Diego , Woolrich Mark W. , Winkler Anderson M. , Karapanagiotidis Theodoros , Smallwood Jonathan , Nichols Thomas E.
Published: February 2018

Spatial or temporal aspects of neural organisation are known to be important indices of how cognition is organised. However, measurements and estimations are often noisy and many of the algorithms used are probabilistic, which in combination have been argued to limit studies exploring the neural basis of specific aspects of cognition. Focusing on static and dynamic functional connectivity estimations, we propose to leverage this variability to improve statistical efficiency in relating these estimations to behaviour. To achieve this goal, we use a procedure based on permutation testing that provides a way of combining the results from many individual tests that refer to the same hypothesis. This is needed when testing a measure whose value is obtained from a noisy process, which can be repeated multiple times, referred to as replications. Focusing on functional connectivity, this noisy process can be: (i) computational, e.g. when using an approximate inference algorithm for which different runs can produce different results or (ii) observational, if we have the capacity to acquire data multiple times, and the different acquired data sets can be considered noisy examples of some underlying truth. In both cases, we are not interested in the individual replications but on the unobserved process generating each replication. In this note, we show how results can be combined instead of choosing just one of the estimated models. Using both simulations and real data, we show the benefits of this approach in practice.
Mutant p53 controls tumor metabolism and metastasis by regulating PGC-1α
Authors: Basu Subhasree , Gnanapradeepan Keerthana , Barnoud Thibaut , Kung Che-Pei , Tavecchio Michele , Scott Jeremy , Watters Andrea , Chen Qing , Kossenkov Andrew V. , Murphy Maureen E.
Published: February 2018

Mutant forms of p53 protein often possess protumorigenic functions, conferring increased survival and migration to tumor cells via their “gain-of-function” activity. Whether and how a common polymorphism in TP53 at amino acid 72 (Pro72Arg; referred to here as P72 and R72) impacts this gain of function has not been determined. We show that mutant p53 enhances migration and metastasis of tumors through the ability to bind and regulate PGC-1α and that this regulation is markedly impacted by the codon 72 polymorphism. Tumor cells with the R72 variant of mutant p53 show increased PGC-1α function along with greatly increased mitochondrial function and metastatic capability. Breast cancers containing mutant p53 and the R72 variant show poorer prognosis compared with P72. The combined results reveal PGC-1α as a novel “gain-of-function” partner of mutant p53 and indicate that the codon 72 polymorphism influences the impact of mutant p53 on metabolism and metastasis.
A high-energy-resolution resonant inelastic X-ray scattering spectrometer at ID20 of the European Synchrotron Radiation Facility
Authors: Moretti Sala M. , Martel K. , Henriquet C. , Al Zein A. , Simonelli L. , Sahle Ch. J. , Gonzalez H. , Lagier M.-C. , Ponchut C. , Huotari S. , Verbeni R. , Krisch M. , Monaco G.
Published: February 2018

An end-station for resonant inelastic X-ray scattering and (resonant) X-ray emission spectroscopy at beamline ID20 of ESRF – The European Synchrotron is presented. The spectrometer hosts five crystal analysers in Rowland geometry for large solid angle collection and is mounted on a rotatable arm for scattering in both the horizontal and vertical planes. The spectrometer is optimized for high-energy-resolution applications, including partial fluorescence yield or high-energy-resolution fluorescence detected X-ray absorption spectroscopy and the study of elementary electronic excitations in solids. In addition, it can be used for non-resonant inelastic X-ray scattering measurements of valence electron excitations.
3-(1,2,2-Triiodoethenyl)benzoic acid
Authors: Szell Patrick M.J. , Gabidullin Bulat , Bryce David L.
Published: February 2018

The title compound, C9H5I3O2, has a layered structure exhibiting O—H...O hydrogen bonds, as well as C—I...C and C—I...O halogen bonding. The C atoms of the ethenyl group are disordered over two sets of sites with refined occupancies of 0.545 (18) and 0.455 (18).
Beyond exchange and prosocial motives, is altruistic helping a valid motive for organizational citizenship behavior?
Authors: Cheung Fung Yi Millissa , Peng Kelly , Wong Chi-Sum
Published: February 2018

Purpose

The argument in this study is that employees differ in their motives in helping their organizations when they know that they may not be paid back for their efforts. This paper aims to examine whether these motives will lead to greater extra-role contribution in an organization.

Design/methodology/approach

The data of 124 pairs of employee in China have been used to develop and test the measurement of an “altruistic helping of organization” (AHO) in a pilot sample. In addition, AHO had been then tested as a motive for organizational citizenship behavior (OCB) using data collected from 245 pairs of employees in China.

Findings

Data from 124 pairs of employees in China have been used to develop and test the measurement of “altruistic helping of organization” in a pilot sample. The authors have proposed and validated whether procedural justice and conscientiousness predict for a new OCB motive – AHO, which explains for an incremental predictive power over the existing motives of OCB, namely, instrumentality, social exchange with the organization, organizational concern, prosocial values and impression management, on a data collected from 245 pairs of employees in China.

Research limitations/implications

This is a cross-sectional study. In addition, the authors have only taken in samples in China, which may not be generalizable to other context.

Practical implications

Practitioners can devote resources to encourage employees to help without any consideration of returns. In addition, the fairness perception of organizational practices – procedural justice and individual characteristics – are necessary to induce AHO and other OCB motives.

Social implications

This research provides that the social implication of arousing the basic underpinning of driving OCB is altruistic motive and not egoistic. This finding helps to stimulate individuals to have more helping behaviors towards the organization.

Originality/value

This study provides solid evidence for the suggestion by the original proponents of OCB that the distinction between rewarded and unrewarded criterion is blurred in OCB literature. Our findings suggest that altruistic helping does exist and that this explains for a significant proportion of extra-role behavior.
fMRI neuromarketing and consumer learning theory
Authors: Hsu Melissa Yi-Ting , Cheng Julian Ming-Sung
Published: February 2018

Purpose

The purpose of this paper is to examine the impact of gender on the neural substrates of theories on consumer behavior (i.e. the original compared with the revised versions of consumer learning [CL] theory) and to examine whether gender influences brain activation associated with word-of-mouth (WOM) communications (i.e. information specificity, source expertise and tie strength) after a product harm crisis. This article also discusses the WOM effects of product quality perception, negative emotion and purchase intentions by precise localizing brain activity.

Design/methodology/approach

This study applied functional magnetic resonance imaging to measure brain activity (i.e. the blood oxygen level-dependent signal) during WOM communication after a product harm crisis.

Findings

The male participants treat the product quality as a constant and tend to support the original CL theory. The female participants, however, showed differentiable brain activation across three factors, suggesting a dynamic representation for product quality (i.e. not a constant), and they appear to be more sensitive to the revised CL theory.

Originality/value

This paper concluded that the original CL theory applies to males and the revised version applies to females. Therefore, gender determines whether the original or the revised version of the CL theory works in consumers’ decision-making, and the extant of research has not focused on the information after a product harm crisis in terms of whether the information being communicated is specific or tensile through WOM communication.
UAV attitude estimation based on the dual filtering methods
Authors: Zhuang Zhemin , Guo Zhijie , Joseph Raj Alex Noel , Guo Canzhu
Published: February 2018

Purpose

A toy UAV performs tumbling, rolling, racing and other complex activities. It is based on low-cost hardware and hence requires a better algorithm to estimate the attitudes more accurately with low power consumption. The proposed technique based on optimized Madgwick filter and moving average filter (MAF) ensures improved convergence speed in estimating the attitude, achieves higher accuracy and provides robustness and stability of the toy UAV. The paper aims to discuss this issue.

Design/methodology/approach

Traditional methods are prone to problems such as slow convergence speed and errors in calculation of the attitude angles. These errors cause the vehicle to drift and tremble, thus affecting the overall stability of the vehicle. The proposed method combines the features of optimized Madgwick filter and MAF to provide better accuracy, achieved through the fusion of gyroscope and accelerometer data, and zero correction to eliminate the random drift error of the gyroscope and removal of high-frequency interference by MAF of the accelerometer data. The experimental results on actual flight data showed that the method was better than the conventional Madgwick and Mahony complementary filters.

Findings

The performance of the proposed method was analyzed by estimating the pitch and roll angles under the static and dynamic condition of the toy UAV. The results were compared with two traditional methods: Madgwick and Mahony complement filter. In the static condition, the variance and average error while estimating the attitudes was comparatively lower than the traditional method. For the dynamic conditions, the convergence time to achieve a prescribed swing angle was again lower than the traditional method. From these two experiments, it can be seen that the proposed method provides better attitude estimation at lower computation time.

Originality/value

The proposed method combines the optimized Madgwick filter and MAF to accuracy estimate the attitude of toy UAV. The algorithm mainly suits the toy UAVs which are based on low-cost hardware and require better control systems to ensure stability of the vehicle. The experimental results on real flight data illustrate that the method not only improves the convergence speed in estimating the attitude angle for large maneuvers of the toy UAV, but also achieves higher accuracy in the attitude estimation, thus ensuring the robustness and stability of the UAV.
UAV and obstacle sensing techniques – a perspective
Authors: Aswini N. , Krishna Kumar E. , Uma S.V.
Published: February 2018

Purpose

The purpose of this paper is to provide an overview of unmanned aerial vehicle (UAV) developments, types, the major functional components of UAV, challenges, and trends of UAVs, and among the various challenges, the authors are concentrating more on obstacle sensing methods. This also highlights the scope of on-board vision-based obstacle sensing for miniature UAVs.

Design/methodology/approach

The paper initially discusses the basic functional elements of UAV, then considers the different challenges faced by UAV designers. The authors have narrowed down the study on obstacle detection and sensing methods for autonomous operation.

Findings

Among the various existing obstacle sensing techniques, on-board vision-based obstacle detection has better scope in the future requirements of miniature UAVs to make it completely autonomous.

Originality/value

The paper gives original review points by doing a thorough literature survey on various obstacle sensing techniques used for UAVs.
A matter of perspective – the role of interpersonal relationships in supply chain risk management
Authors: Durach Christian F. , Machuca José A.D.
Published: February 2018

Purpose

The purpose of this paper is to, first, explore the role of interpersonal relationships between buying and supplying firms in the management of supply chain disruptions (SCDs). Interpersonal connections are proposed as “social lubricants” that can advance the knowledge about conventional interorganizational antecedents of firm resilience. Differentiating between high- and low-complexity manufacturing industries, the study then looks into how managers from these industry clusters can leverage the efficacy of these relationships through the appropriate use of interorganizational governance mechanisms.

Design/methodology/approach

Structural equation modeling is conducted with data collected from 229 manufacturing firms in Austria, Germany and Switzerland. Industry clusters are formed via a Q-sort exercise.

Findings

Results support the assumption of a socially embedded, interpersonal dimension in buyer-supplier relationships that impact organizational-level resilience. It is suggested that investments in interpersonal skills and interpersonal complementarity are significant antecedents of both relational and re-deployable firm resilience. Surprisingly, no support was found for a positive impact of interpersonal information sharing on firm resilience, challenging findings from previous studies on an interorganizational level. Interorganizational governance and industry affiliation each have moderating effects on the performance of the resilience efficacy of interpersonal relationship antecedents, suggesting the existence of an important managerial lever.

Originality/value

Integrating the supply chain and behavioral science literature, this study is the first to investigate the interplay of interpersonal and organizational antecedents and their efficacy in the management of SCDs.
The governance of collaboration in complex projects
Authors: Chakkol Mehmet , Selviaridis Kostas , Finne Max
Published: February 2018

Purpose

Inter-organisational collaboration is becoming increasingly important in complex projects; some project customers even formally require evidence of collaborative competence from potential providers. The purpose of this paper is to explore the governance of collaboration and the ways in which it is enacted in practice for complex projects.

Design/methodology/approach

The study is based on a qualitative analysis of 29 semi-structured interviews, primary data from meetings and events supported by secondary data, including standards and industry-specific contract templates.

Findings

The paper identifies how collaboration can be effectively governed in complex projects through the emerging role of the collaboration standard and its impact on contractual and relational governance mechanisms. The standard sets higher-level institutional guidelines that affect the way in which collaboration is governed in complex projects. It helps formalise informal relational practices whilst also providing guidelines for building flexibility in contracts by including coordination- and adaptation-oriented provisions conducive to collaboration.

Originality/value

The paper demonstrates the emerging role of the collaboration standard and its influence on contractual and relational mechanisms deployed in complex projects. It shows how the standard can formalise and codify informal collaborative practices and help transfer related learning across projects, thereby contributing towards the dual requirement for standardisation and flexibility in project settings.
The role of the Troika on the Greek central government accounting reforms
Authors: Cohen Sandra , Karatzimas Sotirios
Published: February 2018

Purpose

The purpose of this paper is to explore the role of the Troika’s advent played in the progress of the budgeting and the financial reporting systems reform at the Greek central government level.

Design/methodology/approach

The approach of an extreme country case study is adopted. The data used in the paper have been identified through document analysis performed on the relevant documents produced by the Troika, the Greek Ministry of Finance, and other relevant sources. The reform process is seen through the lens of the neo-institutional theory and the resource dependency theory.

Findings

Although both reforms targeted the introduction of best international practices – particularly useful in periods of financial distress and scarce resources – the advent of the Troika affected their progress and changed the priorities. As a result, the reform was redirected toward strengthening the cash budgeting system.

Research limitations/implications

The study is subject to the limitations of an extreme case study research.

Practical implications

This is a case where resource dependency changes political priorities and directions and affects the evolvement of state budget and accounting reforms under way.

Originality/value

The role of external fund providers in public sector financial management reform priority-setting, in the case of a developed Eurozone country, is analyzed. The study contributes to the research agenda on accounting practices in times of austerity.
Experimental investigation on the tribological properties of modified carbon nanotubes as the additive in castor oil
Authors: Qian Shanhua , Wang Hongyue , Huang Chuanhui , Zhao Yongwu
Published: February 2018

Purpose

This paper aims to modify carbon nanotubes with oleic acid, and to study the tribological properties of castor oil with modified carbon nanotubes additives. The proper additives are sought for the future engineering application of castor oil.

Design/methodology/approach

Tribological properties of the castor oils mixed with the modified carbon nanotubes of four mass percentages were investigated using a four-ball testing rig. Coefficient of friction and wear scar diameter were obtained in each test, and the mechanism of modified carbon nanotubes and castor oil was discussed.

Findings

The results indicated that modified carbon nanotubes had better dispersion in castor oil. Coefficient of friction first increased, then decreased and finally grew stable with the time, and wear scar diameter of steel surface functioned as a first reduced then increased change with the additive mass percentage of modified carbon nanotubes. The minimum of average coefficient of friction and wear scar diameter occurred at 0.02 Wt.% modified carbon nanotubes.

Originality/value

A small amount of modified carbon nanotubes could improve properties of the castor oil, and the mixed castor oil with 0.02 Wt.% modified carbon nanotubes would be most possibly used in engineering applications.
Theoretical and experimental modeling of impact wear
Authors: Akhondizadeh Mehdi , Fooladi Mahani Majid , Rezaeizadeh Masoud , S. Mansouri Hoseyn
Published: February 2018

Purpose

Oblique impacts which occur in many situations in mineral industries leads to material removal and fail of mechanical parts. Studies will be helpful in optimal design to have minimum machine malfunctions.

Design/methodology/approach

In the present work, the Hertz-Di Maio Di Renzo nonlinear model of contact is used to simulate the impact phenomenon as a micro-sliding process. The modified Archard equation is used to evaluate wear over the impact. The wear coefficient is evaluated by a pin-disk machine. An impact-wear tester is used to validate the model results.

Findings

The measurements indicate an increase in surface hardness because of the several impacts. It is considered in the wear predictive model.

Originality/value

The model predictions compared with the experimental data, obtained from the impact-wear tester, show that the model well predicts the impact wear and can be used as a predictive tool to study the practical design problems and to explain some phenomena associated with the percussive impact.
Investigation into the lubricating gap between the ring gear and the case in internal gear pumps
Authors: Du Ruilong , Chen Yinglong , Zhou Hua
Published: February 2018

Purpose

The purpose of this paper is to propose a simulation model for studying the lubricating gap between the ring gear and the case in internal gear pumps.

Design/methodology/approach

The pressure distribution of the wedge-shaped oil film between the ring gear and the case is obtained based on the theory of film lubrication using the Reynolds equation implemented with MATLAB. After that, the balance of the ring gear is achieved by the radial micro motion of the ring gear. The power loss due to the leakage and the shear stress is then calculated for optimized design of the radial clearance.

Findings

The hydrodynamic effect and the squeezing effect of the wedge-shaped oil film play a role in the hydrodynamic balance of the ring gear, and they become more intense when the operating speed gets lower and the pressure gets higher. The optimal radial clearance should stay between 20 and 25 µm for the minimum power loss.

Originality/value

The present research provides the first simulation model that treats the oil film between the ring gear and the case as wedge-shaped oil film and explains why the ring gear stays balanced. Furthermore, the simulation model can be regarded as a tool for optimized design of the radial clearance.
Expectations gap, anticipated regret, and behavior intention in the context of rapid technology evolvement
Authors: Ha Youngwook
Published: February 2018

Purpose

The purpose of this paper is to examine how the gap between the expected benefit of the current system and that of the future upgraded system affects consumer behavior when adopting a new technology.

Design/methodology/approach

The study extends the regret theory to establish a structural model of expectations gap, anticipated regret, and behavior intention. Next, it conducts an online survey on the potential users of intelligent closed circuit television for home use.

Findings

The expected benefit of the current system is not only a direct precedence factor for consumer behavior, but also forms the anticipated regret through comparison with the expected benefit of the upgraded system in the future, thereby proving that this ultimately affects consumer behavior.

Originality/value

Regret is an interesting emotion that could have significant impact on consumers’ adoption/purchasing behaviors. While there are some studies in the IS literature on regret, it is still understudied. This study analyzes the characteristics of IT products with rapid technological change in terms of consumers’ regret.