bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced critical current density in the pressure-induced magnetic state of the high-temperature superconductor FeSe
Authors: Jung Soon-Gil , Kang Ji-Hoon , Park Eunsung , Lee Sangyun , Lin Jiunn-Yuan , Chareev Dmitriy A. , Vasiliev Alexander N. , Park Tuson 
Published: November 2015

AbstractWe investigate the relation of the critical current density (Jc) and the remarkably increased superconducting transition temperature (Tc) for the FeSe single crystals under pressures up to 2.43 GPa, where the Tc is increased by ~8 K/GPa. The critical current density corresponding to the free flux flow is monotonically enhanced by pressure which is due to the increase in Tc, whereas the depinning critical current density at which the vortex starts to move is more influenced by the pressure-induced magnetic state compared to the increase of Tc. Unlike other high-Tc superconductors, FeSe is not magnetic, but superconducting at ambient pressure. Above a critical pressure where magnetic state is induced and coexists with superconductivity, the depinning Jc abruptly increases even though the increase of the zero-resistivity Tc is negligible, directly indicating that the flux pinning property compared to the Tc enhancement is a more crucial factor for an achievement of a large Jc. In addition, the sharp increase in Jc in the coexisting superconducting phase of FeSe demonstrates that vortices can be effectively trapped by the competing antiferromagnetic order, even though its antagonistic nature against superconductivity is well documented. These results provide new guidance toward technological applications of high-temperature superconductors.
SENP1 desensitizes hypoxic ovarian cancer cells to cisplatin by up-regulating HIF-1α
Authors: Ao Qilin , Su Wenjing , Guo Shuang , Cai Lei , Huang Lei 
Published: November 2015

AbstractHypoxia-inducible factor 1 alpha (HIF-1α) is closely related to chemoresistance of ovarian cancers. Although it is reported that HIF-1α can be regulated by Sentrin/SUMO-specific protease 1 (SENP1), the effects of SENP1 on HIF-1α is still controversial. In this study, we identified that SENP1 positively regulated the expression of HIF-1α by deSUMOylation and weakened the sensitivity of hypoxic ovarian cancer cells to cisplatin. These results indicate that SENP1 is a positive regulator of HIF-1α and plays a negative role in ovarian cancer chemotherapy.
Transdifferentiation of periodontal ligament-derived stem cells into retinal ganglion-like cells and its microRNA signature
Authors: Ng Tsz Kin , Yung Jasmine S. Y. , Choy Kwong Wai , Cao Di , Leung Christopher K. S. , Cheung Herman S. , Pang Chi Pui 
Published: November 2015

AbstractRetinal diseases are the leading causes of irreversible visual impairment and blindness in the developed countries. Human retina has limited regenerative power to replace cell loss. Stem cell replacement therapy has been proposed as a viable option. Previously, we have induced human adult periodontal ligament stem cells (PDLSCs) to the retinal lineage. In this study, we modified our induction protocol to direct human adult PDLSCs into retinal ganglion-like cells and determined the microRNA (miRNA) signature of this transdifferentiation process. The differentiated PDLSCs demonstrated the characteristics of functional neurons as they expressed neuronal and retinal ganglion cell markers (ATOH7, POU4F2, β-III tubulin, MAP2, TAU, NEUROD1 and SIX3), formed synapses and showed glutamate-induced calcium responses as well as spontaneous electrical activities. The global miRNA expression profiling identified 44 upregulated and 27 downregulated human miRNAs after retinal induction. Gene ontology analysis of the predicted miRNA target genes confirmed the transdifferentiation is closely related to neuronal differentiation processes. Furthermore, the expressions of 2 miRNA-targeted candidates, VEGF and PTEN, were significantly upregulated during the induction process. This study identified the transdifferentiation process of human adult stem cells into retinal ganglion-like cells and revealed the involvement of both genetic and miRNA regulatory mechanisms.
Metformin inhibits hepatocellular glucose, lipid and cholesterol biosynthetic pathways by transcriptionally suppressing steroid receptor coactivator 2 (SRC-2)
Authors: Madsen Andre , Bozickovic Olivera , Bjune Jan-Inge , Mellgren Gunnar , Sagen Jørn V. 
Published: November 2015

AbstractThe ability of the anti-diabetic drug metformin to inhibit anabolic processes including gluconeogenesis and lipogenesis is partly attributable to activation of the AMP-activated protein kinase (AMPK) pathway. The p160 steroid receptor coactivator 2 (SRC-2) is a key regulator of cellular metabolism and drives expression of the gluconeogenic enzyme glucose-6-phosphatase (G6Pc). Here, we uncovered a role for SRC-2 in the metabolic reprogramming imposed by metformin. In FaO cells, metformin dose-dependently reduced mRNA expression of SRC-2. Microarray analysis of metformin-treated cells revealed an overrepresentation of downregulated genes involved in biosynthesis of lipids and cholesterol. Several metformin-regulated genes including fatty acid synthase (FASN) were validated as transcriptional targets of SRC-2 with promoters characterized by sterol regulatory element (SRE) binding protein (SREBP) recognition sequences. Transactivation assays of the FASN promoter confirmed that SRC-2 is a coactivator of SREBP-1. By suppressing SRC-2 at the transcriptional level, metformin impeded recruitment of SRC-2 and RNA polymerase II to the G6Pc promoter and to SREs of mutual SRC-2/SREBP-1 target gene promoters. Hepatocellular fat accretion was reduced by metformin or knock-down of both SRC-2 and SREBP-1. Accordingly we propose that metformin inhibits glucose and lipid biosynthesis partly by downregulating SRC-2 gene expression.
The Biarzo case in northern Italy: is the temporal dynamic of swine mitochondrial DNA lineages in Europe related to domestication?
Authors: Vai Stefania , Vilaça Sibelle Torres , Romandini Matteo , Benazzo Andrea , Visentini Paola , Modolo Marta , Bertolini Marco , MacQueen Peggy , Austin Jeremy , Cooper Alan , Caramelli David , Lari Martina , Bertorelle Giorgio 
Published: November 2015

AbstractGenetically-based reconstructions of the history of pig domestication in Europe are based on two major pillars: 1) the temporal changes of mitochondrial DNA lineages are related to domestication; 2) Near Eastern haplotypes which appeared and then disappeared in some sites across Europe are genetic markers of the first Near Eastern domestic pigs. We typed a small but informative fragment of the mitochondrial DNA in 23 Sus scrofa samples from a site in north eastern Italy (Biarzo shelter) which provides a continuous record across a ≈6,000 year time frame from the Upper Palaeolithic to the Neolithic. We additionally carried out several radiocarbon dating. We found that a rapid mitochondrial DNA turnover occurred during the Mesolithic, suggesting that substantial changes in the composition of pig mitochondrial lineages can occur naturally across few millennia independently of domestication processes. Moreover, so-called Near Eastern haplotypes were present here at least two millennia before the arrival of Neolithic package in the same area. Consequently, we recommend a re-evaluation of the previous idea that Neolithic farmers introduced pigs domesticated in the Near East and that Mesolithic communities acquired domestic pigs via cultural exchanges, to include the possibility of a more parsimonious hypothesis of local domestication in Europe.
Phase boundary of hot dense fluid hydrogen
Authors: Ohta Kenji , Ichimaru Kota , Einaga Mari , Kawaguchi Sho , Shimizu Katsuya , Matsuoka Takahiro , Hirao Naohisa , Ohishi Yasuo 
Published: November 2015

AbstractWe investigated the phase transformation of hot dense fluid hydrogen using static high-pressure laser-heating experiments in a laser-heated diamond anvil cell. The results show anomalies in the heating efficiency that are likely to be attributed to the phase transition from a diatomic to monoatomic fluid hydrogen (plasma phase transition) in the pressure range between 82 and 106 GPa. This study imposes tighter constraints on the location of the hydrogen plasma phase transition boundary and suggests higher critical point than that predicted by the theoretical calculations.
Spectral shifting of speaker‐specific information for narrow band telephonic speaker recognition
Authors: Thiruvaran T. , Sethu V. , Ambikairajah E. , Li H. 
Published: November 2015

Speech‐based authentication system can perform remote authentication over telephone channels. However, telephone channels are restricted to a bandwidth of ∼0–4 kHz while studies on the distribution of speaker‐specific information in the speech spectrum strongly suggests that useful speaker‐specific information is present above 4 kHz. A method to shift a part of this speaker‐specific information above 4 kHz into the telephone bandwidth in place of less speaker‐specific information originally present below 4 kHz is proposed. Speaker recognition experiments conducted using the proposed method leads to ∼18.5% relative improvement on equal error rate when compared to a system using the conventional telephone band speech, as evaluated on the Intelligence Advanced Research Projects Activity (IARPA) Babel Program Tamil language collection.
Die Rolle psychologischer und technikbezogener Persönlichkeitsmerkmale sowie individueller Wissensbestände von Ärztinnen und Ärzten für die Adoption des Telemonitorings in der medizinischen Versorgung
Authors: Dockweiler C. , Hornberg C. 
Published: November 2015

Zusammenfassung
Hintergrund: Informations- und Kommunikationstechnologien gewinnen im Gesundheitswesen zunehmend an Bedeutung. Insbesondere Leistungen des Telemonitorings zeigen im Rahmen randomisierter klinischer Studien erste medizinische Evidenz mit Blick auf die Steigerung der Versorgungsqualität, die Verringerung stationärer Aufenthalte und die Reduzierung von Behandlungskosten. Für die Erschließung der angedeuteten Potenziale und die langfristige Implementation in die Versorgungspraxis ist eine nutzerinnen- und nutzerorientierte Technikentwicklung unter Berücksichtigung häufig komplexer Strukturen der Technikakzeptanz erforderlich.
Methden: Einstellungen und Haltungen sowie die vorliegenden Wissensbestände zum Telemonitoring vonseiten klinisch tätiger Ärztinnen und Ärzte (Zufallsstichprobe, N=614) wurden im Rahmen einer online-basierten Erhebung mit einer Rücklaufquote von 21% (n=133) ermittelt. Zur Analyse der Herausbildung positiver Haltungsmuster gegenüber Telemonitoringanwendungen wurden Wirkungszusammenhänge zwischen psychologischen und technikbezogenen Persönlichkeitsmerkmalen sowie den wahrgenommenen Wissensbeständen ermittelt.
Ergebnisse: Positive Einstellungsmuster gegenüber dem Telemonitoring werden maßgeblich durch das individuelle Wissen und die Verträglichkeit (als Persönlichkeitsmerkmal, welches stark durch altruistische Züge und zwischenmenschliches Vertrauen geprägt ist) eines Individuums beeinflusst. Die Einstellungen zum Telemonitoring sind mit dem Ziel einer qualitativen Verbesserung der Versorgungssituation klar nutzwertorientiert und unterscheiden sich nach Versorgungssektor und Geschlecht. Insgesamt fühlen sich nur 57% der befragten Ärztinnen und Ärzte ausreichend über den Einsatz des Telemonitorings informiert.
Schlussfolgerung: Vor dem Hintergrund der Nutzwertorientierung im Rahmen der Einstellungsbildung kommt der evidenzbasierten Entwicklung der Telemedizin eine besondere Bedeutung für eine gelingende Adoption zu. Hierfür bedarf es zukünftig deutlicherer Bemühungen im Wissenstransfer, im Austausch von Best-Practice-Lösungen und der Verankerung der Telemedizin in Aus- und Fortbildung.
Nutzenbewertung der minimal-invasiven Schulterchirurgie aus Sicht der Kostenträger
Authors: Schlothauer N. , Willers J. , Enders D. , von Knoch M. 
Published: November 2015

ZusammenfassungAm Beispiel der minimal-invasiven Schulterchirurgie werden die Arbeitsunfähigkeitstage als ein Teil der indirekten Kosten abgebildet und in die Bewertung der Wirtschaftlichkeit der Behandlungsmethode mit einbezogen. Für 266 Versicherte wurde die Dauer der Arbeitsunfähigkeit nach einer stationär durchgeführten Schulterarthroskopie bestimmt. Die Dauer und Höhe der Krankengeldzahlungen betrugen im Durchschnitt pro Teilnehmer 9,5 Tage bzw. 485,00 €. Versicherte, die maximal 50 Jahre alt waren, hatten signifikant mehr Krankengeldtage als Versicherte über 50 Jahre. Krankengeldzahlungen als indirekte Kosten einer Krankenbehandlung konnten effizient über Sekundärdatenanalysen erhoben und bewertet werden.
Surface sensitivity of total reflection high-energy positron diffraction
Authors: Hyodo Toshio , Fukaya Yuki , Mochizuki Izumi , Maekawa Masaki , Wada Ken , Shidara Tetsuo , Ichimiya Ayahiko , Kawasuso Atsuo 
Published: November 2015

Reflection high-energy positron diffraction (RHEPD) is the positron counterpart of reflection high-energy electron diffraction (RHEED). RHEPD was proposed in 1992 [1], and first demonstrated in 1998 [2]. Unlike the case of the electron, the potential energy of the positron inside a crystal is positive, and hence positrons incident on a crystal surface with a glancing angle smaller than a certain critical angle are totally reflected. This feature makes the positrons a tool extremely sensitive to the topmost layer of the crystal surface. Recent development of a brightness-enhanced intense positron beam at KEK [K. Wada, et al., J. Phys.: Conf. Ser. 443, 012082 (2013)] has made it possible to obtain clear RHEPD patterns. We rename the technique with a refined beam as "total reflection high-energy positron diffraction (TRHEPD)". Here we demonstrate that the TRHEPD pattern from the Si(111)-7x7 DAS surface taken with a glancing angle smaller than the critical angle for the total reflection is essentially determined only by the atoms exposed on the surface (adatoms and the atoms in the first surface layer) [3]. The technical details of the positron beam preparation [M. Maekawa, et al., to be published in Eur. Phys. J. D (2014)], results on the Pt/Ge(001) nano-wire surface[I. Mochizuki, et al., Phys. Rev. B 85, 245438 (2012)], TiO2(110)-1x2 surface, and silicene on Ag(111) surface [Y. Fukaya, et al., Phys. Rev. B 88 205413 (2013)] are also presented in this conference.
Accurate water site determination in macromolecular refinement using 3D-RSIM
Authors: Borbulevych Oleg , Truchon Jean-François , Labute Paul , Westerhoff Lance 
Published: November 2015

Structure Based Drug Discovery (SBDD) is employed by virtually all pharmaceutical R&D organizations, and understanding the protein:ligand complex structure along with explicit solvent effects is necessary to obtain meaningful results from docking, thermodynamic calculations, and active site exploration. Phenix/DivCon is able to accurately elucidate the protein:ligand complex structure through in situ treatment of the structure using quantum mechanics; however, at standard SBDD resolutions, the crystallographic data unambiguously reveals only a small fraction of water molecules in protein crystals - even within the first hydrogen shell of the protein molecule. Further, the implicit solvent correction in conventional methods does not take into account non-linear effects of hydrogen bonding and dispersion interactions introduced by the nearest hydration shells. To address this deficiency, we have used the 3D Reference Interaction Site Model (3D-RISM) method as implemented in MOE to filter crystallographic map data and create a more complete first solvation shell of the biomolecular complex. The combination, implemented within the Phenix/DivCon refinement workflow, allows us to capture weaker difference density peaks and thus "rescue" water sites that are normally undetectable using conventional crystallographic protocols. This workflow has been applied to "standard" resolution structures, and the results have been compared to corresponding higher-resolution structures. We have observed consistent improvements in R-factors and in water site determination. For example, the lysozyme structure PDBid:2EPE (2.5 Å) has 48 crystallographic waters while PDBid:193L (1.33 Å) has 142 waters. When considering overlapping sites, 2EPE captures 30% of the waters found in 193L. When our method is applied to 2EPE however, it is able to find almost 60% of the waters observed in the higher-resolution, and it is able to predict sites that may have been missed at the higher resolution.
Identifying the correct d-block element with aspherical scattering factors
Authors: Dittrich Birger , Roesky Herbert , Singh Amit , Sidhu Navdeep 
Published: November 2015

Element assignment in single-crystal X-ray diffraction (XRD) is based on the number of electrons of a particular atom, so that neighboring elements in the periodic table are often hard to distinguish. 3d-block carbene complexes, e.g. [1], provide examples where the situation is even worse: use of the independent-atom model (IAM) leads to significantly better figures of merit for the element left to the correct one in the periodic table, and the element can hence not be identified by XRD using the IAM without prior chemical knowledge. This is readily explained by the characteristics of the ligand, which can cause electron-deficiency at the metal center. Hence Cu instead of Zn gives a significantly better fit to the diffraction data in the IAM in our example, although the heavier element is unambiguously present. Rearrangements in the aspherical valence electron-density distribution (EDD) hence forbid to reliably distinguish and to correctly identify the metal atom in such coordination compounds with conventional methodology, whereas aspherical scattering factors allow a correct assignment. These findings clearly illustrate the need to sometimes go beyond "spherical-atoms". We show how "whole molecule" aspherical scattering factors derived from theoretical computations within the Hansen/Coppens mutlipole model EDD description [2a] can be successfully used in least-squares refinement. A related approach is Hirshfeld-atom refinement [2b], but for network structures, disordered molecules and those with atoms on special positions this approach is not always technically feasible. The suggested modeling procedure is based on the invariom database [3] and its capability to predict quantum chemical X-H bond distances involving hydrogen, and is amenable to d-block compounds where all-electron calculations are possible. Due to the important role of aspherical EDD in the vicinity of the central atom we expect that similar behavior will occur in linear and square-planar, but not in tetrahedral and octahedral coordination.
New platforms for gas separations and storage, chemical sensing, and catalysis
Authors: Zaworotko Michael , Perry John 
Published: November 2015

Over the past two decades Metal-Organic Materials (MOMs), as exemplified by porous coordination polymers, discrete metal-organic polyhedra and metal-organic frameworks, have experienced tremendous growth in both the number of research papers and their impact. MOMs are receiving such attention thanks to their modular nature which affords them the potential to offer game-changing solutions for several important technological problems. MOMs can exhibit permanent porosity and many of their most anticipated applications, such as gas storage (carbon dioxide sequestration, natural gas, and hydrogen storage for energy applications), chemical separations, chemical sensing, catalysis, and drug delivery, involve the uptake or encapsulation of guests. Further, as they can often be obtained in a crystalline form, MOMs are also well suited to act as platforms materials for probing structure-property relationships. This presentation will survey several promising new MOM platforms that are being pursued by our research group and will address their performance with respect to carbon dioxide capture and sequestration, natural gas storage, and catalysis. Additionally, we will place these results in the context of the "2-step" crystal engineering principles that guided our research into the rational design of these high-performance materials (see Figure).
Controlling Crystal Structure in Embedded Magnetic Nanoparticles
Authors: Baker Steve , Roy Mervyn , Binns Chris , Lees Martin 
Published: November 2015

Magnetic nanoparticles and nanocomposite materials have attracted much interest due to their novel magnetic behaviour, and their potential use in a range of applications. One of the main reasons for their novel magnetism, appreciated for some time, is the high proportion of under-coordinated atoms at the surface of nanoparticles. In the case of magnetic transition metals this leads to a narrowing of the 3d bands that are responsible for magnetism in these materials, leading to size-dependent nanoparticle properties. The atomic structure adopted by nanoparticles is also a key factor in determining their magnetism. Unlike in bulk materials atomic structure in nanoparticles can be changed more readily by, for example, embedding them in suitable matrix materials. Here we describe how a high level of control over crystal structure in nanoparticles can be achieved, using EXAFS to "fingerprint" their crystal structure, and show how this in turn leads to a high degree of control over nanoparticle magnetism. We describe a flexible co-deposition process based around a gas aggregation source, which enables a high degree of control over structure in transition metal nanoparticles embedded in various matrices. EXAFS experiments and analysis used to probe atomic structure in embedded Fe and Co nanoparticles are described [1]. Examples presented include the system of Fe nanoparticles embedded in a CuAu alloy matrix where we show that is not only the ability to change the atomic structure of embedded nanoparticles that is important but the ability to fine-tune their structure once changed [2]. In this case, this enables the atomic magnetic Fe moment to be fine-tuned to a value higher than in the bulk Fe structure, in agreement with theory. In some systems alloying at the particle/interface can be significant. We describe how this is the case for Fe nanoparticles in Pd [3], and how such alloying could be useful in forming magnetic nanocomposites with superior properties.
Polyhalides as scaffolds for supramolecular, ion-conducting crown ether stacks
Authors: Fromm Katharina , Crochet Aurélien , Dagri Cyrille , Chérémond Yvens 
Published: November 2015

Crown ethers, such as dibenzo-18-crown-6 (DB18C6) are in principle perfect building blocks to be stacked on top of each other for one-dimensional (1D) channel formation. However, in the more than 1000 publications on crown ethers in the solid state, only one case was of channel formation described, but not as main focus of research.[1] We now present a way to systematically induce the stacking of DB18C6 with the help of polyhalides, which play the roles of scaffolds via halogen bonding.[2] These compounds can be considered as "supramolecular straws". Using for example potassium as couter ion for triiodide for example, we obtained a solid which contains three differently filled, parallel channels in the solid state, which are arranged between the polyhalide anions. Exchanging potassium with sodium by immersion of a single crystal into NaOH solution leads to a single-crystal-to-single-crystal transformation into a compound with two channel types. This transition from a system crystallizing initially in the P2-space group to yield a compound in Pccn is only possible under these very special conditions. We will further present how the ion transport through these channels can be quantified and which process is involved in ion exchange. The role of the polyhalide anions, which cannot be replaced by other linear anions, will be emphasized as well.