bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical and molecular characteristics of Chinese patients with X‐linked lymphoproliferative syndrome type 1
Authors: An Yun‐Fei , Luo Xiao‐Bo , Yang Xi , Wang Jing , Li Li , Zhao Xiao‐Dong
Published: July 2014

Background

X‐linked lymphoproliferative syndrome type 1 (XLP1) is a rare inherited, life‐threatening immunodeficiency disorder caused by mutations in SH2D1A gene. It affect approximately two to three males per million. Fewer than 10 cases with definite gene mutations have been reported in Chinese mainland and no rapid diagnosis method has been established.

Procedure

We determined the clinical and molecular characteristics of five patients with XLP1. The SH2D1A gene were amplified by PCR and sequenced, the SAP expression was analyzed by flow cytometry.

Results

Two patients had novel SH2D1A mutations and three had mutations that have been previously reported. Three patients presented with fulminant infectious mononucleosis or hemophagocytic lymphohistiocytosis and one presented with lymphoma. Null or decreased SAP expression on PBMCs was noted. The remaining patient presented with unique, recurrent, nonfulminant infectious mononucleosis and bimodal intracellular SAP protein expression.

Conclusions

The overall molecular characteristics and clinical phenotypes of Chinese patients with XLP1 matched previous reports. The unique bimodal intracellular SAP protein expression indicated the presence of some residual SAP‐positive T cells that are able to respond to persistent Epstein–Barr virus infection and could explain the relatively mild clinical phenotype of this patient. Pediatr Blood Cancer 2014;61:2043–2047. © 2014 Wiley Periodicals, Inc.
The Effect of Optimism Bias on the Decision to Terminate Failing Projects
Authors: Meyer Werner G.
Published: July 2014

This research presents the findings from an experiment that investigated to what extent decision makers suffer from optimism bias when escalating a commitment to failing projects; 345 individuals, involved in project decision making, participated in the experiment. A new form of optimism bias, namely post-project optimism bias, is defined. Post-project optimism bias is an overly optimistic belief that a project will deliver better business benefits than what was planned or that can be proven. It is further confirmed that both post-project and in-project optimism biases have significant effects on the escalation of commitment to failing projects.
Developing a Framework for Embedding Useful Project Management Improvement Initiatives in Organizations
Authors: Fernandes Gabriela , Ward Stephen , Araújo Madalena
Published: July 2014

This paper describes the quantitative analysis phase of an exploratory study to identify useful project management improvement initiatives and factors contributing to their successful embedment in organizations. A preliminary framework, based on a literature review and a series of interviews with practitioners, was tested via a questionnaire, which elicited 793 responses from project management practitioners worldwide. The paper focuses on factor analyses of the questionnaire responses, addressing issues of construct validity and reliability. The resulting final framework highlights 15 key project management improvement initiatives and 26 embedding factors grouped by the factor analyses into three project management improvement initiative themes and six embedding themes.
Genetic engineering combined with random mutagenesis to enhance G418 production inMicromonospora echinospora
Authors: Ni Xianpu , Sun Zhenpeng , Zhang Hongyu , He Han , Ji Zhouxiang , Xia Huanzhang
Published: July 2014

G418, produced by fermentation of Micromonospora echinospora, is an aminoglycoside antibiotic commonly used in genetic selection and maintenance of eukaryotic cells. Besides G418, M. echinospora produces many G418 analogs. As a result, the G418 product always contains impurities such as gentamicin C1, C1a, C2, C2a, gentamicin A and gentamicin X2. These impurities are less potent but more toxic than G418, but the purification of G418 is difficult because it has similar properties to its impurities. G418 is an intermediate in the gentamicin biosynthesis pathway. From G418 the pathway proceeds via successive dehydrogenation and aminotransferation at the C-6′ position to generate the gentamicin C complex, but genes responsible for these steps are still obscure. Through disruption of gacJ, which is deduced to encode a C-6′ dehydrogenase, the biosynthetic impurities gentamicin C1, C1a, C2 and C2a were all removed, and G418 became the main product of the gacJ disruption strain. These results demonstrated that gacJ is in charge of conversion of the 6′-OH of G418 into 6′-NH2. Disruption of gacJ not only eliminates the impurities seen in the original strain but also improves G418 titers by 15-fold. G418 production was further improved by 26.6 % through traditional random mutagenesis. Through the use of combined traditional and recombinant genetic techniques, we produced a strain from which most impurities were removed and G418 production was improved by 19 fold.
Test of the anomalous scaling of passive temperature fluctuations in turbulent Rayleigh–Bénard convection with spatial inhomogeneity
Authors: He Xiaozhou , Shang Xiao-dong , Tong Penger
Published: July 2014

The scaling properties of the temperature structure function (SF) and temperature–velocity cross-structure function (CSF) are investigated in turbulent Rayleigh–Bénard convection (RBC). The measured SFs and CSFs exhibit good scaling in space and time and the resulting SF and CSF exponents are obtained both at the centre of the convection cell and near the sidewall. A universal relationship between the CSF exponent and the thermal dissipation exponent is found, confirming that the anomalous scaling of passive temperature fluctuations in turbulent RBC is indeed caused by the spatial intermittency of the thermal dissipation field. It is also found that the difference in the functional form of the measured SF and CSF exponents at the two different locations in the cell is caused by the change of the geometry of the most dissipative structures in the (inhomogeneous) temperature field from being sheetlike at the cell centre to filament-like near the sidewall. The experiment thus provides direct evidence showing that the universality features of turbulent cascade are linked to the degree of anisotropy and inhomogeneity of turbulent statistics.
Electrophoresis of bubbles
Authors: Schnitzer Ory , Frankel Itzchak , Yariv Ehud
Published: July 2014

Smoluchowski’s celebrated electrophoresis formula is inapplicable to field-driven motion of drops and bubbles with mobile interfaces. We here analyse bubble electrophoresis in the thin-double-layer limit. To this end, we employ a systematic asymptotic procedure starting from the standard electrokinetic equations and a simple physicochemical interface model. This furnishes a coarse-grained macroscale description where the Debye-layer physics is embodied in effective boundary conditions. These conditions, in turn, represent a non-conventional driving mechanism for electrokinetic flows, where bulk concentration polarization, engendered by the interaction of the electric field and the Debye layer, results in a Marangoni-like shear stress. Remarkably, the electro-osmotic velocity jump at the macroscale level does not affect the electrophoretic velocity. Regular approximations are obtained in the respective cases of small zeta potentials, small ions, and weak applied fields. The nonlinear small-zeta-potential approximation rationalizes the paradoxical zero mobility predicted by the linearized scheme of Booth (J. Chem. Phys., vol. 19, 1951, pp. 1331–1336). For large (millimetre-size) bubbles the pertinent limit is actually that of strong fields. We have carried out a matched-asymptotic-expansion analysis of this singular limit, where salt polarization is confined to a narrow diffusive layer. This analysis establishes that the bubble velocity scales as the $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}2/3$-power of the applied-field magnitude and yields its explicit functional dependence upon a specific combination of the zeta potential and the ionic drag coefficient. The latter is provided to within an $O(1)$ numerical pre-factor which, in turn, is calculated via the solution of a universal (parameter-free) nonlinear flow problem. It is demonstrated that, with increasing field magnitude, all numerical solutions of the macroscale model indeed collapse on the analytic approximation thus obtained. Existing measurements of clean-bubble electrophoresis agree neither with present theory nor with previous models; we discuss this ongoing discrepancy.
Role of slipstream instability in formation of counter-rotating vortex rings ahead of a compressible vortex ring
Authors: Dora C. L. , Murugan T. , De S. , Das Debopam
Published: July 2014

Counter-rotating vortex rings (CRVRs) are observed to form ahead of a primary compressible vortex ring that is generated at the open end of a shock tube at sufficiently high Mach numbers. In most of the earlier studies, the embedded shock strength has been asserted as the cause for the formation of CRVRs. In the present study, particle image velocimetry (PIV) measurements and high-order numerical simulations show that CRVRs do not form in the absence of a Mach disk in the sonic under-expanded jet behind the primary vortex ring. Kelvin–Helmholtz-type shear flow instability of the slipstream originating from the triple point of the Mach disk and subsequent eddy pairing, as observed by Rikanati et al. (Phys. Rev. Lett., vol. 96, 2006, art. 174503) in shock-wave Mach reflection, is found to be responsible for CRVR formation. The growth rate of the slipstream in the present problem follows the model proposed by them. The parameters influencing the formation of CRVRs as well as their dynamics is investigated. It is found that the strength of the Mach disk and its duration of persistence results in an exit impulse that determines the number of CRVRs formed.
Selection for soyabeans with high and environmentally stable lutein concentrations
Authors: Dhakal Krishna Hari , Choung Myoung-Gun , Hwang Young-Sun , Fritschi Felix B. , Shannon J. Grover , Lee Jeong-Dong
Published: July 2014

Lutein has significant nutritional benefits for human health. Therefore, enhancing soybean lutein concentrations is an important breeding objective. However, selection for soybeans with high and environmentally stable lutein concentrations has been limited. The objectives of this study were to select soybeans with high seed lutein concentrations and to determine the stability of lutein concentrations across environments. A total of 314 genotypes were screened and 18 genotypes with high lutein concentrations and five genotypes with low lutein concentrations were selected for further examination. These 23 genotypes and two check varieties were evaluated under six environments (two planting dates for 2 years at one location and two planting dates for 1 year at another location). Lutein concentrations were influenced by genotype, environment and genotype × environment interactions. Genotypes with late maturity and low lutein concentrations were more stable than those with early maturity and high concentrations. Early (May) planting resulted in greater lutein concentrations than late (June) planting. Among the genotypes evaluated, PI603423B (7.7 μg/g) and PI89772 (5.8 μg/g) had the greatest mean lutein concentrations and exhibited medium and high stability across the six environments, respectively. Thus, these genotypes may be useful for breeding soybeans with high and stable seed lutein concentrations.
Molecular evaluation of Afghan wheat landraces
Authors: Manickavelu Alagu , Niwa Sayaka , Ayumi Kosaka , Komatsu Kenji , Naruoka Yukiko , Ban Tomohiro
Published: July 2014

The wheat landraces collected by Dr Hitoshi Kiharaet al.from Afghanistan, the place of secondary origin of wheat, are an untapped genetic resource for mining novel alleles. In this study, approximately 400 landraces were collected from seven agroecological zones and characterized using diversity array technology and single-nucleotide polymorphism markers, as well as diagnostic molecular markers at important loci controlling vernalization (Vrn), photoperiod response (Ppd), grain colour (R), leaf rust (Lr), yellow rust (Yr), stem rust (Sr) and Fusarium head blight (Fhb). A genome-wide marker array revealed a large amount of genetic diversity among the landraces, 53% of which were winter types, 43% were either spring types or facultative and 4% were either unknown or hadVrn-A1c– a rare spring allele that needs to be confirmed with additional genotyping and phenotyping. AtPpd, 97% of the lines carried a photosensitive allele. In the case of grain colour, classification based on dominant or recessive allelic combinations revealed that approximately 39% of the population is characterized by white grain. Four gene-specific markers that were targeted to identify loci for rust and Fhb resistance enabled us to identify 17 unique landraces with known resistance genes.
Proteomic identification of a fucosyltransferase from petals of milk thistle, Silybum marianum
Authors: Mishra Siddhartha Kumar , Sangwan Neelam S. , Srivastava Manoj Kumar , Mishra Bhawana , Sangwan Rajender Singh
Published: July 2014

Fucosyltransferases are a group of enzymes that catalyse the transfer of l-fucose from a donor substrate to an acceptor molecule. Silybum marianum is also called ‘milk thistle’ due to its characteristic flower shape. It produces two major flavonoids: silymarin and silybin. The plant and its major secondary metabolites are used for treatment/recovery after chronic liver disease, liver rehabilitation after hepatitis and treatment of gallbladder disease. These compounds also act as antioxidants for scavenging free radicals and inhibiting lipid peroxidation. We identified two peptide motifs (YYEAYLSHADEK and TTPDPSCGR designated as motif 1 and motif 2, respectively) of a fucosyltransferase derived from S. marianum that are highly conserved in its counterparts across the plant species and sources. The nature and properties of the motifs are discussed in terms of their putative participation in catalysis and enzyme/active site conformation.
Plant-specific VQ-domain proteins as interaction partners of WRKY transcription factors
Authors: Kwon Soon Il , Hwang D. J.
Published: July 2014

VQ-domain proteins are known to interact with WRKY transcription factors and have been reported to be involved in plant defence responses to environmental stresses inArabidopsis. Thus, elucidation of the defence mechanisms during the interaction of VQ-domain proteins and WRKY transcription factors could provide useful insights into the regulation of VQ-domain protein-mediated WRKY transcription factors. As the focus of this review, we summarize the genomic analysis of the VQ-domain proteins as one of the WRKY-interacting proteins and their biological effects during plant stress conditions inArabidopsisand rice.
Variation in seedling root traits in wild barley (Hordeum vulgare L. ssp. spontaneum) germplasm
Authors: Tyagi Kuldeep , Lee Hyo Jeong , Lee Chong Ae , Steffenson Brian J. , Kim Young Jin , Yun Song Joong
Published: July 2014

Improved root architecture of cultivated barley can improve crop performance in drought-prone areas. In this study, seedlings of 315 wild barley (Hordeum vulgare subsp. spontaneum) accessions from the Wild Barley Diversity Collection (WBDC) were grown under hydroponic conditions for 8 d after germination and then root characteristics were analysed. Significant differences were observed among the accessions with regard to seminal root number (SRN), root length (RL), specific root length (SRL), root fresh weight and root dry weight (RDW). Principal component analysis explained about 81% of the total variation for ten traits. Principal component (PC) 1, PC2 and PC3 explained about 38, 30 and 13% of the total variation among the accessions. The two most prominent contributors in each PC were RL and SRL, RDW and SRN, and the longitude and latitude of the collection sites, respectively. Accessions WBDC266, WBDC302, WBDC286 and WBDC011 had the longest RL and the highest RDW, specific dry root weight and SRL, respectively. These accessions may be useful genetic resources for the improvement of these root traits in cultivated barley.
Lysosome sorting of β-glucocerebrosidase by LIMP-2 is targeted by the mannose 6-phosphate receptor
Authors: Zhao Yuguang , Ren Jingshan , Padilla-Parra Sergi , Fry Elizabeth E. , Stuart David I.
Published: July 2014

The integral membrane protein LIMP-2 has been a paradigm for mannose 6-phosphate receptor (MPR) independent lysosomal targeting, binding to β-glucocerebrosidase (β-GCase) and directing it to the lysosome, before dissociating in the late-endosomal/lysosomal compartments. Here we report structural results illuminating how LIMP-2 binds and releases β-GCase according to changes in pH, via a histidine trigger, and suggesting that LIMP-2 localizes the ceramide portion of the substrate adjacent to the β-GCase catalytic site. Remarkably, we find that LIMP-2 bears P-Man9GlcNAc2 covalently attached to residue N325, and that it binds MPR, via mannose 6-phosphate, with a similar affinity to that observed between LIMP-2 and β-GCase. The binding sites for β-GCase and the MPR are functionally separate, so that a stable ternary complex can be formed. By fluorescence lifetime imaging microscopy, we also demonstrate that LIMP-2 interacts with MPR in living cells. These results revise the accepted view of LIMP-2–β-GCase lysosomal targeting.
Local mapping of detector response for reliable quantum state estimation
Authors: Cooper Merlin , Karpiński Michał , Smith Brian J.
Published: July 2014

Improved measurement techniques are central to technological development and foundational scientific exploration. Quantum physics relies on detectors sensitive to non-classical features of systems, enabling precise tests of physical laws and quantum-enhanced technologies including precision measurement and secure communications. Accurate detector response calibration for quantum-scale inputs is key to future research and development in these cognate areas. To address this requirement, quantum detector tomography has been recently introduced. However, this technique becomes increasingly challenging as the complexity of the detector response and input space grow in a number of measurement outcomes and required probe states, leading to further demands on experiments and data analysis. Here we present an experimental implementation of a versatile, alternative characterization technique to address many-outcome quantum detectors that limits the input calibration region and does not involve numerical post processing. To demonstrate the applicability of this approach, the calibrated detector is subsequently used to estimate non-classical photon number states.
An electromagnetic field disrupts negative geotaxis in Drosophila via a CRY-dependent pathway
Authors: Fedele Giorgio , Green Edward W. , Rosato Ezio , Kyriacou Charalambos P.
Published: July 2014

Many higher animals have evolved the ability to use the Earth’s magnetic field, particularly for orientation. Drosophila melanogaster also respond to electromagnetic fields (EMFs), although the reported effects are quite modest. Here we report that negative geotaxis in flies, scored as climbing, is disrupted by a static EMF, and this is mediated by cryptochrome (CRY), the blue-light circadian photoreceptor. CRYs may sense EMFs via formation of radical pairs of electrons requiring photoactivation of flavin adenine dinucleotide (FAD) bound near a triad of Trp residues, but mutation of the terminal Trp in the triad maintains EMF responsiveness in climbing. In contrast, deletion of the CRY C terminus disrupts EMF responses, indicating that it plays an important signalling role. CRY expression in a subset of clock neurons, or the photoreceptors, or the antennae, is sufficient to mediate negative geotaxis and EMF sensitivity. Climbing therefore provides a robust and reliable phenotype for studying EMF responses in Drosophila.
Glucose-induced electrical activities and insulin secretion in pancreatic islet β-cells are modulated by CFTR
Authors: Guo Jing Hui , Chen Hui , Ruan Ye Chun , Zhang Xue Lian , Zhang Xiao Hu , Fok Kin Lam , Tsang Lai Ling , Yu Mei Kuen , Huang Wen Qing , Sun Xiao , Chung Yiu Wa , Jiang Xiaohua , Sohma Yoshiro , Chan Hsiao Chang
Published: July 2014

The cause of insulin insufficiency remains unknown in many diabetic cases. Up to 50% adult patients with cystic fibrosis (CF), a disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR), develop CF-related diabetes (CFRD) with most patients exhibiting insulin insufficiency. Here we show that CFTR is a regulator of glucose-dependent electrical acitivities and insulin secretion in β-cells. We demonstrate that glucose elicited whole-cell currents, membrane depolarization, electrical bursts or action potentials, Ca2+oscillations and insulin secretion are abolished or reduced by inhibitors or knockdown of CFTR in primary mouse β-cells or RINm5F β-cell line, or significantly attenuated in CFTR mutant (DF508) mice compared with wild-type mice. VX-809, a newly discovered corrector of DF508 mutation, successfully rescues the defects in DF508 β-cells. Our results reveal a role of CFTR in glucose-induced electrical activities and insulin secretion in β-cells, shed light on the pathogenesis of CFRD and possibly other idiopathic diabetes, and present a potential treatment strategy.
Modelling Lipid Competition Dynamics in Heterogeneous Protocell Populations
Authors: Shirt-Ediss Ben , Ruiz-Mirazo Kepa , Mavelli Fabio , Solé Ricard V.
Published: July 2014

Recent experimental work in the field of synthetic protocell biology has shown that prebiotic vesicles are able to ‘steal’ lipids from each other. This phenomenon is driven purely by asymmetries in the physical state or composition of the vesicle membranes, and, when lipid resource is limited, translates directly into competition amongst the vesicles. Such a scenario is interesting from an origins of life perspective because a rudimentary form of cell-level selection emerges. To sharpen intuition about possible mechanisms underlying this behaviour, experimental work must be complemented with theoretical modelling. The aim of this paper is to provide a coarse-grain mathematical model of protocell lipid competition. Our model is capable of reproducing, often quantitatively, results from core experimental papers that reported distinct types vesicle competition. Additionally, we make some predictions untested in the lab and develop a general numerical method for quickly solving the equilibrium point of a model vesicle population.
Predicting the settlement of coarse granular materials under vertical loading
Authors: Quezada Juan Carlos , Saussine Gilles , Breul Pierre , Radjaï Farhang
Published: July 2014

Granular materials are widely used in industrial processes despite their complex and poorly understood mechanical behaviour both in static and dynamic regimes. A prototypical example is the settlement and compaction of a granular bed under vibrational loading. The elementary mechanisms of this process are still unclear and there is presently no established theory or methodology to predict the settlement and its statistical variability. By means of a parametric study, carried out on a full-scale track and a critical analysis of density relaxation laws, we introduce a novel settlement model in coarse granular materials under cyclic loading. Our extensive experimental data indicate that the settlement process is governed by three independent parameters strongly correlated with the vibration intensity and initial packing fraction. We show that the mean settlement is well predicted by the model with its parameter values extracted from experimental data.
Illuminating surface atoms in nanoclusters by differential X-ray absorption spectroscopy
Authors: Spanjers Charles S. , Senftle Thomas P. , van Duin Adri C. T. , Janik Michael J. , Frenkel Anatoly I. , Rioux Robert M.
Published: July 2014

We use differential extended X-ray absorption fine structure (Δ-EXAFS) to monitor the Ar-induced surface restructuring of silica-supported Pd nanoclusters (1 nm diameter) at 77 K.
An alternative to trial and error methodology in solid phase extraction: an original automated solid phase extraction procedure for analysing PAHs and PAH-derivatives in soot
Authors: Andrade-Eiroa Auréa , Shahla Roya , Romanías Manolis N. , Dagaut Philippe
Published: July 2014

This paper introduces the generalization of reverse-phase HPLC fundamentals to normal-phase liquid chromatography, hydrophilic interaction chromatography (HILIC) and Automated Solid Phase Extraction (A-SPE).
Tuning of physico-chemical characteristics of charged micelles by controlling head group interactions via hydrophobically and sterically modified counter ions
Authors: Chakraborty Subrata , Chakraborty Amitabha , Saha Swapan K.
Published: July 2014

The nature and size of strongly bound counter ions play crucial role in tuning the thermodynamics of micelle formation.
Ultraconfinement of aqueous electrolytic solutions within hydrophilic nanotubes
Authors: Renou Richard , Szymczyk Anthony , Ghoufi Aziz
Published: July 2014

By means of molecular simulations we shed light on the interplay of surface, confinement and salt effects on the structure and dynamics of water and ions highly confined within a hydrophilic silica nanotube.
Unexpected hydrazine hydrate-mediated aerobic oxidation of aryl/ heteroaryl boronic acids to phenols in ambient air
Authors: Zhong Yanzhen , Yuan Linxin , Huang Zheng , Gu Wenchao , Shao Ye , Han Wei
Published: July 2014

A general sub-stoichimetric hydrazine hydrate-mediated aerobic oxidative ipso-hydroxylation of aryl/heteroaryl boronic acids to phenols.
Miktoarm star conjugated multifunctional gold nanoshells: synthesis and an evaluation of biocompatibility and cellular uptake
Authors: Ng Vanessa W. K. , Avti Pramod K. , Bédard Mathieu , Lam Tina , Rouleau Léonie , Tardif Jean-Claude , Rhéaume Éric , Lesage Frédéric , Kakkar Ashok
Published: July 2014

Biocompatible multifunctional gold nanoshells with imaging, stealth/aqueous solubility and therapeutic capabilities show high accumulation into endothelial cells.
Dual light-emitting nanoparticles: second harmonic generation combined with rare-earth photoluminescence
Authors: Mayer Ludovic , Dantelle Géraldine , Jacques Vincent , Perruchas Sandrine , Patriarche Gilles , Roch Jean-François , Gacoin Thierry
Published: July 2014

Dual light emitting KTP@LaPO4:Eu nanoparticles have been synthesized and characterized.
DNA-PKcs-interacting protein KIP binding to TRF2 is required for the maintenance of functional telomeres
Authors: Khadka Prabhat , Lee Ji Hoon , Baek Seung Han , Oh Sue Young , Chung In Kwon
Published: July 2014

Human telomeres associate with shelterin, a six-protein complex that protects chromosome ends from being recognized as sites of DNA damage. The shelterin subunit TRF2 (telomeric repeat-binding factor 2) protects telomeres by facilitating their organization into the protective capping structure. We have reported previously that the DNA-PKcs (DNA-dependent protein kinase catalytic subunit)-interacting protein KIP associates with telomerase through an interaction with hTERT (human telomerase reverse transcriptase). In the present study, we identify KIP as a novel interacting partner of TRF2. KIP is able to interact with both TRF2 and DNA-PKcs at telomeres. Because KIP is required for the association between TRF2 and DNA-PKcs, the interplay of these three proteins may provide a mechanism for the recruitment of DNA-PKcs to telomeres. We also show that KIP binding to TRF2 enhances the telomere-binding activity of TRF2, suggesting that KIP acts as a positive regulator of TRF2 function. Furthermore, depletion of KIP induces DNA-damage response foci at telomeres, thereby leading to induction of growth arrest, cellular senescence and altered cell cycle distribution. Collectively, our findings suggest that KIP, in addition to its association with catalytically active telomerase, plays important roles in the maintenance of functional telomeres and the regulation of telomere-associated DNA-damage response. Thus KIP represents a new pathway for modulating telomerase and telomere function in cancer.
Osteopontin O-glycosylation contributes to its phosphorylation and cell-adhesion properties
Authors: Kariya Yoshinobu , Kanno Mayumi , Matsumoto-Morita Kana , Konno Midori , Yamaguchi Yoshiki , Hashimoto Yasuhiro
Published: July 2014

OPN (osteopontin) is a multiphosphorylated extracellular glycoprotein, which has important roles in bone remodelling, inflammation and cancer metastasis. OPN regulates cell spreading and adhesion primarily through its association with several integrins such as αvβ3, and its phosphorylation affects these processes. However, the mechanism by which OPN O-glycosylation affects these processes is not completely understood. In the present study, we demonstrated that OPN O-glycosylation self-regulates its biological activities and also affects its phosphorylation status. We prepared two recombinant OPNs, WT (wild-type)-OPN and mutant OPN (ΔO-OPN), which lacks five O-glycosylation sites at a threonine/proline-rich region. O-glycan defects in OPN increased its phosphorylation level, as observed by dephosphorylation assays. Moreover, compared with WT-OPN, ΔO-OPN exhibited enhanced cell spreading and adhesion activities and decreased associations with β1 integrins. This suggested that defects in O-glycans in OPN altered these activities, and that β1 integrins have a less important role in adhesion to ΔO-OPN. The cell-adhesion activity of dephosphorylated ΔO-OPN was higher than the cell-adhesion activities of ΔO-OPN and dephosphorylated WT-OPN. This suggested that some of the phosphorylation in ΔO-OPN caused by O-glycan defects and O-glycans of OPN suppressed the OPN cell-adhesion activity. Thus functional activities of OPN can be determined by the combined glycosylation and phosphorylation statuses and not by either status alone.
Histamine-induced Ca2+ signalling is mediated by TRPM4 channels in human adipose-derived stem cells
Authors: Tran Tran Doan Ngoc , Zolochevska Olga , Figueiredo Marxa L. , Wang Hai , Yang Li-Jun , Gimble Jeffrey M. , Yao Shaomian , Cheng Henrique
Published: July 2014

Intracellular Ca2+ oscillations are frequently observed during stem cell differentiation, and there is evidence that it may control adipogenesis. The transient receptor potential melastatin 4 channel (TRPM4) is a key regulator of Ca2+ signals in excitable and non-excitable cells. However, its role in human adipose-derived stem cells (hASCs), in particular during adipogenesis, is unknown. We have investigated TRPM4 in hASCs and examined its impact on histamine-induced Ca2+ signalling and adipogenesis. Using reverse transcription (RT)–PCR, we have identified TRPM4 gene expression in hASCs and human adipose tissue. Electrophysiological recordings revealed currents with the characteristics of those reported for the channel. Furthermore, molecular suppression of TRPM4 with shRNA diminished the Ca2+ signals generated by histamine stimulation, mainly via histamine receptor 1 (H1) receptors. The increases in intracellular Ca2+ were due to influx via voltage-dependent Ca2+ channels (VDCCs) of the L-type (Cav1.2) and release from the endoplasmic reticulum. Inhibition of TRPM4 by shRNA inhibited adipogenesis as indicated by the reduction in lipid droplet accumulation and adipocyte gene expression. These results suggest that TRPM4 is an important regulator of Ca2+ signals generated by histamine in hASCs and is required for adipogenesis.
Radio holography signal reconstruction and shadow inverse synthetic aperture radar imaging in ground‐based forward scatter radar: theory and experimental results
Authors: Hu Cheng , Zhou Chao , Zeng Tao , Long Teng
Published: July 2014

The radio hologram signal (RHS) extraction is the pre‐condition of shadow inverse synthetic aperture radar (SISAR) imaging in forward scatter radar (FSR). However, for a ground‐based FSR imaging system, which usually includes an envelope detection module, it is pretty hard to obtain the complex RHS. Thus a novel method for RHS reconstruction is proposed by considering the relationship between the in‐phase part and the orthogonal part. The operation of envelope detection is never combined with segmented Hilbert transform before in RHS reconstruction and detailed skills in applying the method are discussed with simulations. Then, the proposed method is verified through real experimental data processing, of which a metal board and a microbus are regarded as the targets. Furthermore, target profiles via SISAR imaging processing are achieved very well when using the reconstructed RHS.
High temperature thermoreflectance imaging and transient Harman characterization of thermoelectric energy conversion devices
Authors: Favaloro T. , Ziabari A. , Bahk J.-H. , Burke P. , Lu H. , Bowers J. , Gossard A. , Bian Z. , Shakouri A.
Published: July 2014

Advances in thin film growth technology have enabled the selective engineering of material properties to improve the thermoelectric figure of merit and thus the efficiency of energy conversion devices. Precise characterization at the operational temperature of novel thermoelectric materials is crucial to evaluate their performance and optimize their behavior. However, measurements on thin film devices are subject to complications from the growth substrate, non-ideal contacts, and other thermal and electrical parasitic effects. In this manuscript, we determine the cross-plane thermoelectric material properties in a single measurement of a 25 μm InGaAs thin film with embedded ErAs (0.2%) nanoparticles using the bipolar transient Harman method in conjunction with thermoreflectance thermal imaging at temperatures up to 550 K. This approach eliminates discrepancies and potential device degradation from the multiple measurements necessary to obtain individual material parameters. In addition, we present a strategy for optimizing device geometry to mitigate the effect of both electrical and thermal parasitics during the measurement. Finite element method simulations are utilized to analyze non-uniform current and temperature distributions over the device area as well as the three dimensional current path for accurate extraction of material properties from the thermal images. Results are compared with independent in-plane and 3ω measurements of thermoelectric material properties for the same material composition and are found to match reasonably well; the obtained figure of merit matches within 15% at room and elevated temperatures.
A magnetically shielded room with ultra low residual field and gradient
Authors: Altarev I. , Babcock E. , Beck D. , Burghoff M. , Chesnevskaya S. , Chupp T. , Degenkolb S. , Fan I. , Fierlinger P. , Frei A. , Gutsmiedl E. , Knappe-Grüneberg S. , Kuchler F. , Lauer T. , Link P. , Lins T. , Marino M. , McAndrew J. , Niessen B. , Paul S. , Petzoldt G. , Schläpfer U. , Schnabel A. , Sharma S. , Singh J. , Stoepler R. , Stuiber S. , Sturm M. , Taubenheim B. , Trahms L. , Voigt J. , Zechlau T.
Published: July 2014

A versatile and portable magnetically shielded room with a field of (700 ± 200) pT within a central volume of 1 m × 1 m × 1 m and a field gradient less than 300 pT/m, achieved without any external field stabilization or compensation, is described. This performance represents more than a hundredfold improvement of the state of the art for a two-layer magnetic shield and provides an environment suitable for a next generation of precision experiments in fundamental physics at low energies; in particular, searches for electric dipole moments of fundamental systems and tests of Lorentz-invariance based on spin-precession experiments. Studies of the residual fields and their sources enable improved design of future ultra-low gradient environments and experimental apparatus. This has implications for developments of magnetometry beyond the femto-Tesla scale in, for example, biomagnetism, geosciences, and security applications and in general low-field nuclear magnetic resonance (NMR) measurements.
Coarse-grained modeling of DNA oligomer hybridization: Length, sequence, and salt effects
Authors: Hinckley Daniel M. , Lequieu Joshua P. , de Pablo Juan J.
Published: July 2014

A recently published coarse-grained DNA model [D. M. Hinckley, G. S. Freeman, J. K. Whitmer, and J. J. de Pablo, J. Chem. Phys. 139, 144903 (2013)] is used to study the hybridization mechanism of DNA oligomers. Forward flux sampling is used to construct ensembles of reactive trajectories from which the effects of sequence, length, and ionic strength are revealed. Heterogeneous sequences are observed to hybridize via the canonical zippering mechanism. In contrast, homogeneous sequences hybridize through a slithering mechanism, while more complex base pair displacement processes are observed for repetitive sequences. In all cases, the formation of non-native base pairs leads to an increase in the observed hybridization rate constants beyond those observed in sequences where only native base pairs are permitted. The scaling of rate constants with length is captured by extending existing hybridization theories to account for the formation of non-native base pairs. Furthermore, that scaling is found to be similar for oligomeric and polymeric systems, suggesting that similar physics is involved.
Fast imaging of intact and shattered cryogenic neon pellets
Authors: Wang Zhehui , Combs S. K. , Baylor L. R. , Foust C. R. , Lyttle M. S. , Meitner S. J. , Rasmussen D. A.
Published: July 2014

Compact condensed-matter injection technologies are increasingly used in magnetic fusion. One recent application is in disruption mitigation. An imaging system with less-than-100-µm- and sub-µs-resolution is described and used to characterize intact and shattered cryogenic neon pellets. Shattered pellets contain fine particles ranging from tens of µm to about 7 mm. Time-of-flight analyses indicate that pellets could slow down if hitting the wall of the guide tube. Fast high-resolution imaging systems are thus useful to neon and other condensed-matter injector development.
Potential of ZrO clusters as replacement Pd catalyst
Authors: Behera Swayamprabha , King Nicholas , Samanta Devleena , Jena Puru
Published: July 2014

Atomic clusters with specific size and composition and mimicking the chemistry of elements in the periodic table are commonly known as superatoms. It has been suggested that superatoms could be used to replace elements that are either scarce or expensive. Based on a photoelectron spectroscopy experiment of negatively charged ions, Castleman and co-workers [Proc. Natl. Acad. Sci. U.S.A. 107, 975 (2010)] have recently shown that atoms of Ni, Pd, and Pt which are well known for their catalytic properties, have the same electronic structure as their counterpart isovalent diatomic species, TiO, ZrO, and WC, respectively. Based on this similarity they have suggested that ZrO, for example, could be a replacement catalyst for Pd. Since catalysts are seldom single isolated atoms, one has to demonstrate that clusters of ZrO also have the same electronic structure as same sized Pd clusters. To examine if this is indeed the case, we have calculated the geometries, electronic structure, electron affinity, ionization potential, and hardness of Pdn and (ZrO)n clusters (n = 1-5). We further studied the reaction of these clusters in neutral and charged forms with H2, O2, and CO and found it to be qualitatively different in most cases. These results obtained using density functional theory with hybrid B3LYP functional do not support the view that ZrO clusters can replace Pd as a catalyst.
Dependency of anti-ferro-magnetic coupling strength on Ru spacer thickness of [Co/Pd]n-synthetic-anti-ferro-magnetic layer in perpendicular magnetic-tunnel-junctions fabricated on 12-inch TiN electrode wafer
Authors: Chae Kyo-Suk , Shim Tae-Hun , Park Jea-Gun
Published: July 2014

We investigated the Ru spacer-thickness effect on the anti-ferro-magnetic coupling strength (Jex) of a [Co/Pd]n-synthetic-anti-ferro-magnetic layer fabricated with Co2Fe6B2/MgO based perpendicular-magnetic-tunneling-junction spin-valves on 12-in. TiN electrode wafers. Jex peaked at a certain Ru spacer-thickness: specifically, a Jex of 0.78 erg/cm2 at 0.6 nm, satisfying the Jex criteria for realizing the mass production of terra-bit-level perpendicular-spin-transfer-torque magnetic-random-access-memory. Otherwise, Jex rapidly degraded when the Ru spacer-thickness was less than or higher than 0.6 nm. As a result, the allowable Ru thickness variation should be controlled less than 0.12 nm to satisfy the Jex criteria. However, the Ru spacer-thickness did not influence the tunneling-magneto-resistance (TMR) and resistance-area (RA) of the perpendicular-magnetic-tunneling-junction (p-MTJ) spin-valves since the Ru spacer in the synthetic-anti-ferro-magnetic layer mainly affects the anti-ferro-magnetic coupling efficiency rather than the crystalline linearity of the Co2Fe6B2 free layer/MgO tunneling barrier/Co2Fe6B2 pinned layer, although Co2Fe6B2/MgO based p-MTJ spin-valves ex-situ annealed at 275 °C achieved a TMR of ∼70% at a RA of ∼20 Ω μm2.
The structure of primary instability modes in the steady wake and separation bubble of a square cylinder
Authors: Mao X. , Blackburn H. M.
Published: July 2014

Flows past symmetric two-dimensional bluff bodies such as the circular cylinder, the square cylinder, and the normal flat plate produce large separation bubbles which (in the steady restriction) may become very elongated at comparatively low Reynolds numbers. The present work focuses on the steady/symmetric wake of a square cylinder at Re ⩽ 300, which loses stability to anti-symmetric two-dimensional global modes at Rec = 45. It is observed that while there is a continuous evolution in the parameters of the leading instability mode with increasing Re, a change in spatial structure of the modes begins near Re = 175, where the peak growth rate is found. At lower Re, instability modes are generally associated with the wake downstream of the separation bubble, but as Re increases the origin of the modes migrates into the separated shear layers. At the optimal Reynolds number Re = 175, the base flow streamlines around the end of the bubble are most parallel. The observed relation between structures of the bubble and global instabilities is explained on the basis of local stability analyses.
Decay of helical Kelvin waves on a quantum vortex filament
Authors: Van Gorder Robert A.
Published: July 2014

We study the dynamics of helical Kelvin waves moving along a quantum vortex filament driven by a normal fluid flow. We employ the vector form of the quantum local induction approximation (LIA) due to Schwarz. For an isolated filament, this is an adequate approximation to the full Hall-Vinen-Bekarevich-Khalatnikov dynamics. The motion of such Kelvin waves is both translational (along the quantum vortex filament) and rotational (in the plane orthogonal to the reference axis). We first present an exact closed form solution for the motion of these Kelvin waves in the case of a constant amplitude helix. Such solutions exist for a critical wave number and correspond exactly to the Donnelly-Glaberson instability, so perturbations of such solutions either decay to line filaments or blow-up. This leads us to consider helical Kelvin waves which decay to line filaments. Unlike in the case of constant amplitude helical solutions, the dynamics are much more complicated for the decaying helical waves, owing to the fact that the rate of decay of the helical perturbations along the vortex filament is not constant in time. We give an analytical and numerical description of the motion of decaying helical Kelvin waves, from which we are able to ascertain the influence of the physical parameters on the decay, translational motion along the filament, and rotational motion, of these waves (all of which depend nonlinearly on time). One interesting finding is that the helical Kelvin waves do not decay uniformly. Rather, such waves decay slowly for small time scales, and more rapidly for large time scales. The rotational and translational velocity of the Kelvin waves depend strongly on this rate of decay, and we find that the speed of propagation of a helical Kelvin wave along a quantum filament is large for small time while the wave asymptotically slows as it decays. The rotational velocity of such Kelvin waves along the filament will increase over time, asymptotically reaching a finite value. These decaying Kelvin waves correspond to wave number below the critical value for the Donnelly-Glaberson instability, and hence our results on the Schwarz quantum LIA correspond exactly to what one would expect from prior work on the Donnelly-Glaberson instability.
Lattice degradation by moving voids during reversible electromigration
Authors: Sindermann S. P. , Latz A. , Spoddig D. , Schoeppner C. , Wolf D. E. , Dumpich G. , Meyer zu Heringdorf F.-J.
Published: July 2014

Electromigration driven void motion is studied in Ag wires with an initially well-defined single crystal lattice by in situ scanning electron microscopy. Voids are moving in opposite direction to the electron flow. When the electron current is reversed, voids exactly retrace their previous motion path with an increased drift velocity: The microstructure of the Ag wire “remembers” the motion path of the initial voids. To investigate the nature of this memory effect, we analyzed the crystal lattice with electron backscatter diffraction after passing of a void. The results show a permanent lattice degradation caused by the moving void. The implication of this finding for the reversibility of EM will be discussed.
Effects of electron inertia in collisionless magnetic reconnection
Authors: Andrés Nahuel , Martin Luis , Dmitruk Pablo , Gómez Daniel
Published: July 2014

We present a study of collisionless magnetic reconnection within the framework of full two-fluid MHD for a completely ionized hydrogen plasma, retaining the effects of the Hall current, electron pressure and electron inertia. We performed 2.5D simulations using a pseudo-spectral code with no dissipative effects. We check that the ideal invariants of the problem are conserved down to round-off errors. Our numerical results confirm that the change in the topology of the magnetic field lines is exclusively due to the presence of electron inertia. The computed reconnection rates remain a fair fraction of the Alfvén velocity, which therefore qualifies as fast reconnection.
The energetic coupling of scales in gyrokinetic plasma turbulence
Authors: Teaca Bogdan , Navarro Alejandro Bañón , Jenko Frank
Published: July 2014

In magnetized plasma turbulence, the couplings of perpendicular spatial scales that arise due to the nonlinear interactions are analyzed from the perspective of the free-energy exchanges. The plasmas considered here, with appropriate ion or electron adiabatic electro-neutrality responses, are described by the gyrokinetic formalism in a toroidal magnetic geometry. Turbulence develops due to the electrostatic fluctuations driven by temperature gradient instabilities, either ion temperature gradient (ITG) or electron temperature gradient (ETG). The analysis consists in decomposing the system into a series of scale structures, while accounting separately for contributions made by modes possessing special symmetries (e.g., the zonal flow modes). The interaction of these scales is analyzed using the energy transfer functions, including a forward and backward decomposition, scale fluxes, and locality functions. The comparison between the ITG and ETG cases shows that ETG turbulence has a more pronounced classical turbulent behavior, exhibiting a stronger energy cascade, with implications for gyrokinetic turbulence modeling.