bluuebunny/crossref_metadata_2025 huggingface dataset:
Planetary Nebulae and their parent stellar populations. Tracing the mass assembly of M87 and Intracluster light in the Virgo cluster core
Authors: Arnaboldi Magda , Longobardi Alessia , Gerhard Ortwin
Published: May 2016

The diffuse extended outer regions of galaxies are hard to study because they are faint, with typical surface brightness of 1% of the dark night sky. We can tackle this problem by using resolved star tracers which remain visible at large distances from the galaxy centers. This article describes the use of Planetary Nebulae as tracers and the calibration of their properties as indicators of the star formation history, mean age and metallicity of the parent stars in the Milky Way and Local Group galaxies. We then report on the results from a deep, extended, planetary nebulae survey in a 0.5 deg2region centered on the brightest cluster galaxy NGC 4486 (M87) in the Virgo cluster core, carried out with SuprimeCam@Subaru and FLAMES-GIRAFFE@VLT. Two planetary nebulae populations are identified out to 150 kpc distance from the center of M87. One population is associated with the M87 halo and the second one with the intracluster light in the Virgo cluster core. They have different line-of-sight velocity and spatial distributions, as well as different planetary nebulae specific frequencies and luminosity functions. The intracluster planetary nebulae in the surveyed region correspond to a luminosity of four times the luminosity of the Large Magellanic Cloud. The M87 halo planetary nebulae trace an older, more metal-rich, parent stellar population. A substructure detected in the projected phase-space of the line-of-sight velocity vs. major axis distance for the M87 halo planetary nebulae provides evidence for the recent accretion event of a satellite galaxy with luminosity twice that of M33. The satellite stars were tidally stripped about 1 Gyr ago, and reached apocenter at a major axis distance of 60–90 kpc from the center of M87. The M87 halo is still growing significantly at the distances where the substructure is detected.
Which processes shape stellar population gradients of massive galaxies at large radii?
Authors: Hirschmann Michaela
Published: May 2016

We investigate the differential impact of physical mechanisms, mergers (stellar accretion) and internal energetic phenomena, on the evolution of stellar population gradients in massive, present-day galaxies employing a set of high-resolution, cosmological zoom simulations. We demonstrate that negative metallicity and color gradients at large radii (>2Reff) originate from the accretion of metal-poor stellar systems. At larger radii, galaxies become typically more dominated by stars accreted from satellite galaxies in major and minor mergers. However, only strong galactic winds can sufficiently reduce the metallicity content of the accreted stars to realistically steepen the outer metallicity and colour gradients in agreement with present-day observations. In contrast, the gradients of the models without winds are inconsistent with observations (too flat). In the wind model, colour and metallicity gradients are significantly steeper for systems which have accreted stars in minor mergers, while galaxies with major mergers have relatively flat gradients, confirming previous results. This analysis greatly highlights the importance of both energetic processes and merger events for stellar population properties of massive galaxies at large radii. Our results are expected to significantly contribute to the interpretation of current and up-coming IFU surveys (like MaNGA and Califa), which in turn can help to better constrain still uncertain models for energetic processes in simulations.
Stellar orbital properties as diagnostics of the origin of the stellar halo
Authors: Valluri Monica , Loebman Sarah R. , Bailin Jeremy , Clarke Adam , Debattista Victor P. , Stinson Greg
Published: May 2016

We examine metallicities, ages and orbital properties of halo stars in a Milky-Way like disk galaxy formed in the cosmological hydrodynamical MaGICC simulations. Halo stars were either accreted from satellites or they formed in situ in the disk or bulge of the galaxy and were then kicked up into the halo (“in situ/kicked-up” stars). Regardless of where they formed both types show surprisingly similar orbital properties: the majority of both types are on short-axis tubes with the same sense of rotation as the disk – implying that a large fraction of satellites are accreted onto the halo with the same sense of angular momentum as the disk.
Chemical Evolution of R-process Elements in the Hierarchical Galaxy Formation
Authors: Komiya Yutaka , Shigeyama Toshikazu
Published: May 2016

The main astronomical source of r-process elements has not yet been identified. One plausible site is neutron star mergers (NSMs). From the perspective of Galactic chemical evolution, however, it has been pointed out that the NSM scenario is incompatible with observations. Recently, Tsujimoto & Shigeyama (2014) pointed out that NSM ejecta can spread into much larger volume than ejecta from a supernova. We re-examine the chemical evolution of r-process elements under the NSM scenario considering this difference in propagation of the ejecta. We find that the NSM scenario can be compatible with the observed abundances of the Milky Way halo stars.
The Milky Way evolution under the RAVE perspective
Authors: Kordopatis Georges ,   on behalf of the RAVE consortium
Published: May 2016

The RAdial Velocity Experiment (RAVE) collected from 2003 to 2013 medium resolution spectra for 5ċ105 low-mass stars of our Galaxy, improving our understanding of the Milky Way evolution and of its properties outside the Solar neighbourhood. This proceeding gives an overview of RAVE results obtained in the last two years.
Investigating the earliest epochs of the Milky Way halo
Authors: Starkenburg Else ,   the Pristine Team
Published: May 2016

Resolved stellar spectroscopy can obtain knowledge about chemical enrichment processes back to the earliest times, when the oldest stars were formed. In this contribution I will review the early (chemical) evolution of the Milky Way halo from an observational perspective. In particular, I will discuss our understanding of the origin of the peculiar abundance patterns in various subclasses of extremely metal-poor stars, taking into account new data from our abundance and radial velocity monitoring programs, and their implications for our understanding of the formation and early evolution of both the Milky Way halo and the satellite dwarf galaxies therein. I conclude by presenting the “Pristine” survey, a program on the Canada-France-Hawaii Telescope to study this intriguing epoch much more efficiently.
Inhomogeneous chemical enrichment in the Galactic Halo
Authors: Kobayashi Chiaki
Published: May 2016

In a galaxy, chemical enrichment takes place in an inhomogeneous fashion, and the Galactic Halo is one of the places where the inhomogeneous effects are imprinted and can be constrained from observations. I show this using my chemodynamical simulations of Milky Way type galaxies. The scatter in the elemental abundances originate from radial migration, merging/accretion of satellite galaxies, local variation of star formation and chemical enrichment, and intrinsic variation of nucleosynthesis yields. In the simulated galaxies, there is no strong age-metallicity relation. This means that the most metal-poor stars are not always the oldest stars, and can be formed in chemically unevolved clouds at later times. The long-lifetime sources of chemical enrichment such as asymptotic giant branch stars or neutron star mergers can contribute at low metallicities. The intrinsic variation of yields are important in the early Universe or metal-poor systems such as in the Galactic halo. The carbon enhancement of extremely metal-poor (EMP) stars can be best explained by faint supernovae, the low [α/Fe] ratios in some EMP stars naturally arise from low-mass (~ 13 - 15M⊙) supernovae, and finally, the [α/Fe] knee in dwarf spheroidal galaxies can be produced by subclasses of Type Ia supernovae such as SN 2002cx-like objects and sub-Chandrasekhar mass explosions.
Searching for chemical relics of first stars with LAMOST and Subaru
Authors: Li Haining , Aoki Wako , Zhao Gang , Honda Satoshi , Christlieb Norbert , Suda Takuma
Published: May 2016

We report progresses of a joint project on searching for extremely metal-poor (EMP) stars based on LAMOST survey and Subaru follow-up observation. Follow-up high-resolution snapshot spectra have been obtained for 70 objects, resulting in 42 EMP stars. A number of chemically interesting objects have already been identified, including (1) Two UMP (ultra metal-poor) stars with [Fe/H] ~ −4.0. One of them is the second UMP turnoff star with Li detection. (2) A super Li-rich (A(Li) ~ 3.1) EMP giant. This is the most metal-poor and extreme example of Li enhancement in giants known to date, and will shed light on Li production during the evolution of red giants. (3) A few EMP stars showing extreme overabundance in heavy elements. Detailed abundances of these extreme objects and statistics obtained by the large sample of EMP stars will provide important constraints on the Galactic halo formation.
Relationships of Vocational Interest Congruence, Differentiation, and Elevation to Career Preparedness Among University Students
Authors: Jaensch Vanessa K. , Hirschi Andreas , Spurk Daniel
Published: May 2016

Abstract. Vocational interest characteristics – interest congruence, interest differentiation, and general interest level (elevation) – are useful indicators for career development. However, research on these issues has primarily focused on adolescents in the transition from school to work and analyzed a limited set of career-related correlates. This study extends this line of research by exploring the relationships of interest congruence, interest differentiation, and interest elevation with several indicators of career preparedness (i. e., career planning, occupational self-efficacy beliefs, career decidedness, and career engagement) among a sample of emerging adults during their university studies in Germany. Data from 239 students representing a wide range of majors were collected via an online questionnaire. Controlling for sociodemographic variables, multiple regression analyses revealed that differentiation was positively associated with career decidedness and career engagement and elevation was positively related to occupational self-efficacy beliefs and career engagement. We discuss the findings regarding the importance of differences in vocational interest characteristics for the career preparedness of university students.
Creative Interests and Personality
Authors: Wiernik Brenton M. , Dilchert Stephan , Ones Deniz S.
Published: May 2016

Abstract. The present study used intraindividual criterion profile analysis to investigate the relationship between creative artistic and investigative interests and the Big Five personality traits. In 19 samples, we found that artistic and investigative interests showed distinct intraindividual personality profile patterns. Investigative interests were associated with elevated openness to intellect, conscientiousness, and emotional stability and low extraversion and agreeableness, relative to individuals’ other traits. Artistic interests were associated with personal strengths for openness to experiences and personal weaknesses for conscientiousness, assertiveness, and emotional stability. Across creative interests, profile pattern, not absolute trait level, drove the relationship between personality traits and interests. These findings replicated across numerous personality inventories and levels of interest specificity (RIASEC, basic interests, occupation-specific interests). We discuss the implications of these results for the complementary use of personality and interest scales in vocational counseling and personnel selection.
Is low-protein diet a possible risk factor of malnutrition in chronic kidney disease patients?
Authors: Noce A , Vidiri M F , Marrone G , Moriconi E , Bocedi A , Capria A , Rovella V , Ricci G , De Lorenzo A , Di Daniele N
Published: May 2016

Chronic kidney disease (CKD) is becoming increasingly widespread in the world. Slowing its progression means to prevent uremic complications and improve quality of life of patients. Currently, a low-protein diet (LPD) is one of the tools most used in renal conservative therapy but a possible risk connected to LPD is protein-energy wasting. The aim of this study is evaluate the possible correlation between LPD and malnutrition onset. We enrolled 41 CKD patients, stages IIIb/IV according to K-DIGO guidelines, who followed for 6 weeks a diet with controlled protein intake (recommended dietary allowance 0.7 g per kilogram Ideal Body Weight per day of protein). Our patients showed a significant decrease of serum albumin values after 6 weeks of LDP (T2) compared with baseline values (T0) (P=0.039), whereas C-reactive protein increased significantly (T0 versus T2; P=0.131). From body composition analysis, a significant impairment of fat-free mass percentage at the end of the study was demonstrated (T0 versus T2; P=0.0489), probably related to total body water increase. The muscular mass, body cell mass and body cell mass index are significantly decreased after 6 weeks of LDP (T2). The phase angle is significantly reduced at the end of the study compared with basal values (T0 versus T2; P=0.0001, and T1 versus T2; P=0.0015). This study indicated that LPD slows down the progression of kidney disease but worsens patients' nutritional state.
Spontaneous helix formation in non-chiral bent-core liquid crystals with fast linear electro-optic effect
Authors: Sreenilayam Sithara P. , Panarin Yuri P. , Vij Jagdish K. , Panov Vitaly P. , Lehmann Anne , Poppe Marco , Prehm Marko , Tschierske Carsten
Published: May 2016

Liquid crystals (LCs) represent one of the foundations of modern communication and photonic technologies. Present display technologies are based mainly on nematic LCs, which suffer from limited response time for use in active colour sequential displays and limited image grey scale. Herein we report the first observation of a spontaneously formed helix in a polar tilted smectic LC phase (SmC phase) of achiral bent-core (BC) molecules with the axis of helix lying parallel to the layer normal and a pitch much shorter than the optical wavelength. This new phase shows fast (∼30 μs) grey-scale switching due to the deformation of the helix by the electric field. Even more importantly, defect-free alignment is easily achieved for the first time for a BC mesogen, thus providing potential use in large-scale devices with fast linear and thresholdless electro-optical response.
MiR-186 inhibited aerobic glycolysis in gastric cancer via HIF-1α regulation
Authors: Liu L , Wang Y , Bai R , Yang K , Tian Z
Published: May 2016

Deregulation of microRNAs in human malignancies has been well documented, among which microRNA-186 (miR-186) has an antiproliferative role in some carcinomas. Here we demonstrate that low expression of miR-186 facilitates aerobic glycolysis in gastric cancer. MiR-186 suppresses cell proliferation induced by hypoxia inducible factor 1 alpha (HIF-1α) in gastric cancer cell lines MKN45 and SGC7901. Cellular glycolysis, including cellular glucose uptake, lactate, ATP/ADP and NAD+/NADH ratios, are also inhibited by miR-186. The negative regulation of miR-186 on HIF-1α effects its downstream targets, including programmed death ligand 1 and two glycolytic key enzymes, hexokinase 2 and platelet-type phosphofructokinase. The antioncogenic effects of miR-186 are proved by in vivo xenograft tumor experiment. The results demonstrate that the miR-186/HIF-1α axis has an antioncogenic role in gastric cancer.
The effect of ageing on the mechanical properties of the silk of the bridge spider Larinioides cornutus (Clerck, 1757)
Authors: Lepore Emiliano , Isaia Marco , Mammola Stefano , Pugno Nicola
Published: May 2016

Spider silk is regarded as one of the best natural polymer fibers especially in terms of low density, high tensile strength and high elongation until breaking. Since only a few bio-engineering studies have been focused on spider silk ageing, we conducted nano-tensile tests on the vertical naturally spun silk fibers of the bridge spiderLarinioides cornutus(Clerck, 1757) (Arachnida, Araneae) to evaluate changes in the mechanical properties of the silk (ultimate stress and strain, Young’s modulus, toughness) over time. We studied the natural process of silk ageing at different time intervals from spinning (20 seconds up to one month), comparing silk fibers spun from adult spiders collected in the field. Data were analyzed using Linear Mixed Models. We detected a positive trend versus time for the Young’s modulus, indicating that aged silks are stiffer and possibly less effective in catching prey. Moreover, we observed a negative trend for the ultimate strain versus time, attesting a general decrement of the resistance force. These trends are interpreted as being due to the drying of the silk protein chains and the reorientation among the fibers.
Characterization and Small RNA Content of Extracellular Vesicles in Follicular Fluid of Developing Bovine Antral Follicles
Authors: Navakanitworakul Raphatphorn , Hung Wei-Ting , Gunewardena Sumedha , Davis John S. , Chotigeat Wilaiwan , Christenson Lane K.
Published: May 2016

Exosomes and microvesicles (i.e., extracellular vesicles: EVs) have been identified within ovarian follicular fluid and recent evidence suggests that EVs are able to elicit profound effects on ovarian cell function. While existence of miRNA within EVs has been reported, whether EV size and concentration as well as their cargos (i.e., proteins and RNA) change during antral follicle growth remains unknown. Extracellular vesicles isolated from follicular fluid of small, medium and large bovine follicles were similar in size, while concentration of EVs decreased progressively as follicle size increased. Electron microscopy indicated a highly purified population of the lipid bilayer enclosed vesicles that were enriched in exosome biomarkers including CD81 and Alix. Small RNA sequencing identified a large number of known and novel miRNAs that changed in the EVs of different size follicles. Ingenuity Pathway Analysis (IPA) indicated that miRNA abundant in small follicle EV preparations were associated with cell proliferation pathways, while those miRNA abundant in large follicle preparations were related to inflammatory response pathways. These studies are the first to demonstrate that EVs change in their levels and makeup during antral follicle development and point to the potential for a unique vesicle-mediated cell-to-cell communication network within the ovarian follicle.
The characteristics of circular disposable devices and in situ devices for optimizing male circumcision: a network meta-analysis
Authors: Fan Yu , Cao Dehong , Wei Qiang , Tang Zhuang , Tan Ping , Yang Lu , Liu Liangren , Liu Zhenhua , Li Xiang , Xue Wenbin
Published: May 2016

In situ device (ISD) and circular disposable device (CDD) are used for optimizing male circumcision (MC), but evidence to explore the characteristics of these two devices is insufficient. In order to explore this issue systematically and provide reliable evidence, ten published randomized controlled trials (RCTs) exploring the safety and efficacy of ISDs and CDDs were included (involving 4649 men). Moderate quality of the RCTs included was found after assessment. Pairwise meta-analyses and network meta-analyses were processed in stata 13.0 and AIDDS v1.16.6 respectively. According to the outcomes that were statistically significant in both pairwise and network meta-analyses, ISD was found to have less intraoperative blood loss (IB), less operative time (OT) and less incidence of wound bleeding (WB) than conventional circumcision (CC); ISD was found to have less WB but more wound healing time (WHT) than CDD; CDD was found to have less IB and less OT than CC. CDD tended to have the best wound healing condition and least pain experience; ISD tended to have the least IB, least OT, least WB, and highest satisfaction rate. With their own superiorities in many aspects, CDD and ISD are both safe and effective devices for optimizing MC.
miRNA let-7b modulates macrophage polarization and enhances tumor-associated macrophages to promote angiogenesis and mobility in prostate cancer
Authors: Wang Zhigang , Xu Lu , Hu Yinying , Huang Yanqin , Zhang Yujuan , Zheng Xiufen , Wang Shanshan , Wang Yifan , Yu Yanrong , Zhang Meng , Yuan Keng , Min Weiping
Published: May 2016

Macrophage polarization is a highly plastic physiological process that responds to a variety of environmental factors by changing macrophage phenotype and function. Tumor-associated macrophages (TAMs) are generally recognized as promoting tumor progression. As universal regulators, microRNAs (miRNAs) are functionally involved in numerous critical cellular processes including macrophage polarization. Let-7b, a miRNA, has differential expression patterns in inflamed tissues compared with healthy controls. However, whether and how miRNA let-7b regulates macrophage phenotype and function is unclear. In this report, we find that up-regulation of let-7b is characteristic of prostatic TAMs and down-regulation of let-7b in TAMs leads to changes in expression profiles of inflammatory cytokines, such as IL-12, IL-23, IL-10 and TNF-α. As a result, TAMs treated with let-7b inhibitors reduce angiogenesis and prostate carcinoma (PCa) cell mobility. Let-7b may play a vital role in regulating macrophage polarization, thus modulating the prognosis of prostate cancer.
Loss of the 14-3-3σ is essential for LASP1-mediated colorectal cancer progression via activating PI3K/AKT signaling pathway
Authors: Shao Ziyun , Cai Yanjun , Xu Lijun , Yao Xueqing , Shi Jiaolong , Zhang Feifei , Luo Yuhao , Zheng Kehong , Liu Jian , Deng Fengliu , Li Rui , Zhang Lanzhi , Wang Hui , Li Mingyi , Ding Yanqing , Zhao Liang
Published: May 2016

LIM and SH3 protein 1 (LASP1) can promote colorectal cancer (CRC) progression and metastasis, but the direct evidence that elucidates the molecular mechanism remains unclear. Here, our proteomic data showed that LASP1 interacted with 14-3-3σ and decreased the expression of 14-3-3σ in CRC. Deletion of 14-3-3σ was required for LASP1-mediated CRC cell aggressiveness. In vitro gain- and loss-of-function assays showed that 14-3-3σ suppressed the ability of cell migration and decreased the phosphorylation of AKT in CRC cells. We further observed clearly co-localization between AKT and 14-3-3σ in CRC cells. Treatment of PI3K inhibitor LY294002 markedly prevented phosphorylation of AKT and subsequently counteract aggressive phenotype mediated by siRNA of 14-3-3σ. Clinically, 14-3-3σ is frequently down-regulated in CRC tissues. Down-regulation of 14-3-3σ is associated with tumor progression and poor prognosis of patients with CRC. Multivariate analysis confirmed low expression of 14-3-3σ as an independent prognostic factor for CRC. A combination of low 14-3-3σ and high LASP1 expression shows a worse trend with overall survival of CRC patients. Our research paves the path to future investigation of the LASP1-14-3-3σ axis as a target for novel anticancer therapies of advanced CRC.
Dynamic Onset of Feynman Relation in the Phonon Regime
Authors: Li Y. , Zhu C. J. , Hagley E. W. , Deng L.
Published: May 2016

The Feynman relation, a much celebrated condensed matter physics gemstone for more than 70 years, predicts that the density excitation spectrum and structure factor of a condensed Bosonic system in the phonon regime drops linear and continuously to zero. Until now, this widely accepted monotonic excitation energy drop as the function of reduced quasi-momentum has never been challenged in a spin-preserving process. We show rigorously that in a light-matter wave-mixing process in a Bosonic quantum gas, an optical-dipole potential arising from the internally-generated field can profoundly alter the Feynman relation and result in a new dynamic relation that exhibits an astonishing non-Feynman-like onset and cut-off in the excitation spectrum of the ground state energy of spin-preserving processes. This is the first time that a nonlinear optical process is shown to actively and significantly alter the density excitation response of a quantum gas. Indeed, this dynamic relation with a non-Feynman onset and cut-off has no correspondence in either nonlinear optics of a normal gas or a phonon-based condensed matter Bogoliubov theory.
Indocyanine-green-loaded microbubbles for localization of sentinel lymph node using near-infrared fluorescence/ultrasound imaging: a feasibility study
Authors: Wang Long , Hu Yihe , Peng Qinghai , Zhou Jiawei , Zhou Qichang , An Senbo , Niu Chengcheng
Published: May 2016

Current strategies for sentinel lymph node (SLN) biopsy to detect cancer metastasis have some limitations such as the associated radiation exposure and high false-negative rates due to dye particles through the true SLNs to contiguous LNs.
A cyclopropene-modified nucleotide for site-specific RNA labeling using genetic alphabet expansion transcription
Authors: Eggert F. , Kath-Schorr S.
Published: May 2016

Site-specific RNA modification with methyl cyclopropene moieties is performed by T7 in vitro transcription. Posttranscriptional labeling of the modified RNA via copper-free click chemistry with a tetrazine-fluorophore conjugate is shown.
Harnessing Lewis acidic open metal sites of metal–organic frameworks: the foremost route to achieve highly selective benzene sorption over cyclohexane
Authors: Mukherjee Soumya , Manna Biplab , Desai Aamod V. , Yin Yuefeng , Krishna Rajamani , Babarao Ravichandar , Ghosh Sujit K.
Published: May 2016

Based on the tactical utilization of the Lewis acidic open metal sites (OMS) functionality; for an OMS-rich, microporous, water-stable series of metal–organic frameworks (M-MOF-74), vapor sorption based efficient selectivity for benzene over cyclohexane has been realized, crucial from industrial separation frontier.
Enhanced electrical properties and field emission characteristics of AZO/ZnO-nanowire core–shell structures
Authors: Huang Jheng-Ming , Tsai Shang-You , Ku Ching-Shun , Lin Chih-Ming , Chen San-Yuan , Lee Hsin-Yi
Published: May 2016

The electrical properties and field-emission characteristics of AZO/ZnO nanowires fabricated using a novel method of atomic layer deposition were systematically investigated.
Nuclear size effects in vibrational spectra
Authors: Almoukhalalati Adel , Shee Avijit , Saue Trond
Published: May 2016

A theoretical study confirms that rovibrational spectroscopy can find bond length changes on the order of 1% of the nuclear radius.
Visible light promoted photocatalytic water oxidation: proton and electron collection via a reversible redox dye mediator
Authors: Walsh Dominic , Sanchez-Ballester Noelia M. , Ting Valeska P. , Ariga Katsuhiko , Weller Mark T.
Published: May 2016

A quinone analogue as reversible electron and proton collector in visible light promoted water oxidations was investigated. Reagents were incorporated into microporous silica with surface absorbed cobalt catalyst. Reversible storage molecules are an important step towards solar fuels.
Computational, electrochemical, and spectroscopic studies of two mononuclear cobaloximes: the influence of an axial pyridine and solvent on the redox behaviour and evidence for pyridine coordination to cobalt(i) and cobalt(ii) metal centres
Authors: Lawrence Mark A. W. , Celestine Michael J. , Artis Edward T. , Joseph Lorne S. , Esquivel Deisy L. , Ledbetter Abram J. , Cropek Donald M. , Jarrett William L. , Bayse Craig A. , Brewer Matthew I. , Holder Alvin A.
Published: May 2016

Co(i)versusCo(ii) in cobaloximes. The effect of a coordinated pyridine.
PNPCB heterocycles via thermal and Lewis acid catalyzed trans-hydroborations
Authors: Fan Louie , Stephan Douglas W.
Published: May 2016

Reactions of iPr2P(BH3)N3 and R2PCCR affords compounds of the form R2P(CCR)NP(BH3)iPr2 which undergo subsequent thermally induced or Lewis acid catalyzed intramolecular hydroboration to give PNPCB heterocycles R2P(CCHPh)NP(BH2)iPr2.
Chromium isotope ratio measurements in environmental matrices by MC-ICP-MS
Authors: Pontér Simon , Pallavicini Nicola , Engström Emma , Baxter Douglas C. , Rodushkin Ilia
Published: May 2016

A single column separation and concentration/isotope ratio measurement method for Cr by ICP-MS (single and multicollector) was evaluated and optimized for geological and biological matrices. Results showδ53Cr homogeneity in different urban soil profiles and suggest isotopically light signature for airborne Cr emitted by steelworks.
Human induced pluripotent stem cell-derived fiber-shaped cardiac tissue on a chip
Authors: Morimoto Y. , Mori S. , Sakai F. , Takeuchi S.
Published: May 2016

A fiber-shaped cellular construct of human iPS-derived cardiomyocytes to quantify the contractile force for analyses of their drug reactivity.
Synthesis of four- and six-armed star-shaped polycarbonates by immortal alternating copolymerization of CO2 and propylene oxide
Authors: Sugimoto Hiroshi , Goto Hidetoshi , Honda Satoshi , Yamada Rumi , Manabe Yoshihisa , Handa Shinya
Published: May 2016

A series of four- and six-armed star-shaped poly(propylene carbonate)s (PPCs) have successfully been synthesized by carbon dioxide (CO2)–propylene oxide (PO) immortal alternating copolymerization initiated either from tetra- or hexa-functional carboxylic acids.
Nonconventional photoluminescence from sulfonated acetone–formaldehyde condensate with aggregation-enhanced emission
Authors: Yu Wei , Wang Zhongyu , Yang Dongjie , Ouyang Xinping , Qiu Xueqing , Li Yuan
Published: May 2016

The fluorescence and aggregation-enhanced emission property of sulfonated acetone–formaldehyde condensate (SAF) with a nonconventional chromophore is reported.
Aromatic-like behavior of germanium nanocrystals
Authors: Behzadi Hadi , khalilnia Zahra
Published: May 2016

Optimized structures of (A) Ge18H12; (B) Ge19H12, peripheral germanium atoms (GeP), middle-layer germanium atoms (GeM) and the central germanium atom (GeC).
Road traffic predictions across major city intersections using multilayer perceptrons and data from multiple intersections located in various places
Authors: Halawa Krzysztof , Bazan Marek , Ciskowski Piotr , Janiczek Tomasz , Kozaczewski Piotr , Rusiecki Andrzej
Published: May 2016

This study presents a novel approach to the road traffic prediction using single multilayer perceptrons and their ensemble. Networks were trained on the basis of real‐world data from the intelligent transportation system Wroclaw. This system is installed in one of the largest cities in Poland. First, a number of neural networks were created, each of which was concurrently able to predict the state of traffic on a number of major intersections located in different parts of the city. Then the multilayer perceptrons were made, which predict the numbers of vehicles passing through selected intersections using the information about previous situations at other intersections. Furthermore, an ensemble method, which combine output values of multiple neural networks, were applied. In the worst case, mean absolute percentage error did not exceed 12.6%, even in cases when traffic prediction was based only on information from other intersections.
1.3.2 Resolution of Alcohols, Amines, Acids, and Esters by Nonhydrolytic Processes
Authors: Rodríguez-Mata M. , Gotor-Fernández V.
Published: May 2016

The use of hydrolases has become a conventional process in organic synthesis, not only for the preparation of optically pure compounds, but also for regio- and chemoselective processes. Their utility for selective transformations under mild reaction conditions make hydrolases attractive catalysts for performing certain transformations that are difficult to achieve by nonenzymatic strategies. Nowadays, many companies use lipases for the preparation of high-added-value compounds and pharmaceuticals because of the advantages of hydrolase-catalyzed processes, which include cost and environmental benefits. Their commercial availability, lack of cofactor dependency, and activity in both aqueous and organic media has allowed the development of asymmetric transformations which are summarized in this chapter. After a brief general introduction discussing the potential of hydrolases in organic synthesis, asymmetric reverse hydrolytic processes are analyzed, substituting the conventional hydrolase nucleophile, water, for other species such as alcohols, amines, esters, or ammonia. The kinetic resolution and dynamic kinetic resolution reactions of alcohols and amines are presented, using esters or carbonates for the production of esters, amides, and carbamates in optically active form. Finally, the resolution of carboxylic acids or esters is described via less-employed interesterification, aminolysis, and ammonolysis processes.
1.4.5 Hydrolysis of Hydantoins, Dihydropyrimidines, and Related Compounds
Authors: Slomka C. , Engel U. , Syldatk C. , Rudat J.
Published: May 2016

Providing advantages including high chemo-, regio-, and enantioselectivity as well as mild reaction conditions, biocatalytic reaction systems are becoming increasingly important for the synthesis of chiral fine chemicals. This chapter focuses on hydantoins and related compounds as promising substrates for the synthesis of optically pure amino acids and on the enzymes involved in these processes. In particular, the production of D-amino acids, such as D-4-hydroxyphenylglycine, via the so-called “hydantoinase process” is now well established. Many investigations regarding the synthesis of L-amino acids with the help of this process have also been carried out. A further interesting application is the synthesis of β-amino acids, which are gaining importance in the pharmaceutical industry due to their special structure. Different possibilities for the application of modified hydantoinase processes are discussed, in which dihydropyrimidines serve as substrates for β-amino acid synthesis. Moreover, various methods to improve the synthesis of amino acids are described.
1.6.2 Glycosyltransferases
Authors: Voglmeir J. , Flitsch S. L.
Published: May 2016

The stereo- and regioselective properties and the high selectivity of glycosyltransferases toward donor and acceptor substrates make these enzymes highly attractive for synthetic applications. Various examples of recombinantly expressed glycosyltransferases demonstrate the versatility of both in vivo and in vitro syntheses of oligosaccharides from milligram to kilogram scale. However, due to the enormous variety of carbohydrate structures in living organisms, to date only a small proportion of carbohydrate epitopes have been synthesized in a routine manner. This chapter summarizes recent approaches to the application of glycosyltransferases in both preparative sugar synthesis and biotransformation.
Molecular dynamics simulation of gold cluster growth during sputter deposition
Authors: Abraham J. W. , Strunskus T. , Faupel F. , Bonitz M.
Published: May 2016

We present a molecular dynamics simulation scheme that we apply to study the time evolution of the self-organized growth process of metal cluster assemblies formed by sputter-deposited gold atoms on a planar surface. The simulation model incorporates the characteristics of the plasma-assisted deposition process and allows for an investigation over a wide range of deposition parameters. It is used to obtain data for the cluster properties which can directly be compared with recently published experimental data for gold on polystyrene [M. Schwartzkopf et al., ACS Appl. Mater. Interfaces 7, 13547 (2015)]. While good agreement is found between the two, the simulations additionally provide valuable time-dependent real-space data of the surface morphology, some of whose details are hidden in the reciprocal-space scattering images that were used for the experimental analysis.
G-mode magnetic force microscopy: Separating magnetic and electrostatic interactions using big data analytics
Authors: Collins Liam , Belianinov Alex , Proksch Roger , Zuo Tingting , Zhang Yong , Liaw Peter K. , Kalinin Sergei V. , Jesse Stephen
Published: May 2016

In this work, we develop a full information capture approach for Magnetic Force Microscopy (MFM), referred to as generalized mode (G-Mode) MFM. G-Mode MFM acquires and stores the full data stream from the photodetector, captured at sampling rates approaching the intrinsic photodiode limit. The data can be subsequently compressed, denoised, and analyzed, without information loss. Here, G-Mode MFM is implemented and compared to the traditional heterodyne-based MFM on model systems, including domain structures in ferromagnetic Yttrium Iron Garnet and the electronically and magnetically inhomogeneous high entropy alloy, CoFeMnNiSn. We investigate the use of information theory to mine the G-Mode MFM data and demonstrate its usefulness for extracting information which may be hidden in traditional MFM modes, including signatures of nonlinearities and mode-coupling phenomena. Finally, we demonstrate detection and separation of magnetic and electrostatic tip-sample interactions from a single G-Mode image, by analyzing the entire frequency response of the cantilever. G-Mode MFM is immediately implementable on any atomic force microscopy platform and as such is expected to be a useful technique for probing spatiotemporal cantilever dynamics and mapping material properties, as well as their mutual interactions.
Radiative decay rate of excitons in square quantum wells: Microscopic modeling and experiment
Authors: Khramtsov E. S. , Belov P. A. , Grigoryev P. S. , Ignatiev I. V. , Verbin S. Yu. , Efimov Yu. P. , Eliseev S. A. , Lovtcius V. A. , Petrov V. V. , Yakovlev S. L.
Published: May 2016

The binding energy and the corresponding wave function of excitons in GaAs-based finite square quantum wells (QWs) are calculated by the direct numerical solution of the three-dimensional Schrödinger equation. The precise results for the lowest exciton state are obtained by the Hamiltonian discretization using the high-order finite-difference scheme. The microscopic calculations are compared with the results obtained by the standard variational approach. The exciton binding energies found by two methods coincide within 0.1 meV for the wide range of QW widths. The radiative decay rate is calculated for QWs of various widths using the exciton wave functions obtained by direct and variational methods. The radiative decay rates are confronted with the experimental data measured for high-quality GaAs/AlGaAs and InGaAs/GaAs QW heterostructures grown by molecular beam epitaxy. The calculated and measured values are in good agreement, though slight differences with earlier calculations of the radiative decay rate are observed.
Magnetization reversal of the domain structure in the anti-perovskite nitride Co3FeN investigated by high-resolution X-ray microscopy
Authors: Hajiri T. , Finizio S. , Vafaee M. , Kuroki Y. , Ando H. , Sakakibara H. , Kleibert A. , Howald L. , Kronast F. , Ueda K. , Asano H. , Kläui M.
Published: May 2016

We performed X-ray magnetic circular dichroism (XMCD) photoemission electron microscopy imaging to reveal the magnetic domain structure of anti-perovskite nitride Co3FeN exhibiting a negative spin polarization. In square and disc patterns, we systematically and quantitatively determined the statistics of the stable states as a function of geometry. By direct imaging during the application of a magnetic field, we revealed the magnetic reversal process in a spatially resolved manner. We compared the hysteresis on the continuous area and the square patterns from the magnetic field-dependent XMCD ratio, which can be explained as resulting from the effect of the shape anisotropy, present in nanostructured thin films.
Cross-plane heat conduction in thin films with ab-initio phonon dispersions and scattering rates
Authors: Vermeersch Bjorn , Carrete Jesús , Mingo Natalio
Published: May 2016

We present a first-principles study of the cross-plane thermal conductivity κ⊥ in a wide variety of semiconductor thin films. We introduce a simple suppression model that matches variance-reduced Monte Carlo simulations with ab-initio phonon dispersions and scattering rates within ≤5% even for anisotropic compounds. This, in turn, enables accurate κ⊥ reconstruction from tabulated cumulative conductivity curves κΣ(Λ⊥). We furthermore reveal, and explain, a distinct quasiballistic regime characterised by a fractional thickness dependence κ⊥∼L2−α in alloys (where α is the Lévy exponent) and logarithmic dependence κ⊥∼ln(L) in single crystals. These observations culminate in the formulation of two compact parametric forms for κ⊥(L) that can fit the first-principles curves across the entire ballistic-diffusive range within a few percent for all investigated compounds.
A sub-μs thermal time constant electrically driven Pt nanoheater: thermo-dynamic design and frequency characterization
Authors: Ottonello Briano Floria , Sohlström Hans , Forsberg Fredrik , Renoux Pauline , Ingvarsson Snorri , Stemme Göran , Gylfason Kristinn B.
Published: May 2016

Metal nanowires can emit coherent polarized thermal radiation, work as uncooled bolometers, and provide localized heating. In this paper, we engineer the temperature dynamics of electrically driven Pt nanoheaters on a silicon-on-insulator substrate. We present three designs and we electrically characterize and model their thermal impedance in the frequency range from 3 Hz to 3 MHz. Finally, we show a temperature modulation of 300 K while consuming less than 5 mW of power, up to a frequency of 1.3 MHz. This result can lead to significant advancements in thermography and absorption spectroscopy.
High-performance beam steering using electrowetting-driven liquid prism fabricated by a simple dip-coating method
Authors: Enrico Clement Carlos , Park Sung-Yong
Published: May 2016

A high degree of beam steering is demonstrated using an electrowetting-driven liquid prism. While prism devices have typically relied on complex and expensive laboratory setups, such as high-vacuum facilities for fabrication of dielectric layers, this work utilizes a simple dip-coating method to provide an ion gel layer as a dielectric, offering 2 or 3 orders higher specific capacitance (c ≈ 10 μF/cm2) than that of conventional dielectrics. Analytical studies present the effects of liquid selection and arrangement on overall prism performance. For experimental demonstrations of high-performance beam steering, we not only selected two immiscible liquids of water and 1-bromonaphthalene (1-BN) oil which provide the large refractive index difference (nwater = 1.33 and n1-BN = 1.65 at λ = 532 nm) between them, but also utilized a double-stacked prism configuration which increases the number of interfaces for incoming light to be steered. At a prism apex angle of φ = 27°, we were able to achieve significantly large beam steering of up to β = 19.06°, which is the highest beam steering performance ever demonstrated using electrowetting technology.
Chromosome evolution in Bulbine glauca (Asphodelaceae or Xanthorrhoeaceae subfam. Asphodeloideae) indicates six species, not one
Authors: Moore Iain S. F. , Brown Elizabeth A. , Telford Ian R. H. , Bruhl Jeremy J.
Published: May 2016

The genus Bulbine Wolf has ~130 species in Africa and only seven species in Australia. Base chromosome numbers in African and Australian Bulbine are x = 7 and x = 12, respectively. This raises the possibility of Australian Bulbine being of polyploidy origin or, alternatively African Bulbine may have evolved through dysploid reduction. Previous chromosome counts in Bulbine glauca (Raf.) E.M.Watson were predominantly 2n = 46, with aneuploid numbers of 2n = 45, 44, 48, 47, 40 and 41 also being encountered within and between populations. Novel chromosome counts are presented here for a wide sample of populations of B. glauca, occurring on volcanic and granite outcrops along the New South Wales and Victorian tablelands and on granite outcrops in Tasmania. Chromosome numbers for Bulbine crassa D.I.Morris and Duretto is 2n = 26. The modal chromosome count for B. glauca is confirmed as 2n = 46 with no evidence of aneuploidy. The species complex shows a variable asymmetric karyotype across its distribution, indicating karyotypic evolution involving structural rearrangements. There appear to be six distinctive groups within the complex based on karyomorphology. Evolutionary changes in both B. glauca s. lat. and B. crassa appear to have not involved recent polyploidy. Variation in chromosome morphology across the B. glauca complex is consistent with our morphological evidence of more than one species.
Expression of a Nicotiana tabacum pathogen-induced gene is involved in the susceptibility to black shank
Authors: Portieles Roxana , Canales Eduardo , Chacon Osmani , Silva Yussuan , Hernández Ingrid , López Yunior , Rodríguez Mayra , Terauchi Ryohei , Matsumura Hideo , Borroto Carlos , Walton Jonathan D. , Santos Ramon , Borrás-Hidalgo Orlando
Published: May 2016

Many host genes induced during compatible plant–pathogen interactions constitute targets of pathogen virulence factors that act to suppress host defenses. In order to identify Nicotiana tabacum L. genes for pathogen-induced proteins involved in susceptibility to the oomycete Phytophthora parasitica var. nicotianae, we used SuperSAGE technology combined with next-generation sequencing to identify transcripts that were differentially upregulated during a compatible interaction. We identified a pathogen-induced gene (NtPIP) that was rapidly induced only during the compatible interaction. Virus-induced gene silencing of NtPIP reduced the susceptibility of N. tabacum to P. parasitica var. nicotianae. Additionally, transient expression of NtPIP in the resistant species Nicotiana megalosiphon Van Heurck & Mull. Arg. compromised the resistance to P. parasitica var. nicotianae. This pathogen-induced protein is therefore a positive regulator of the susceptibility response against an oomycete pathogen in tobacco.
Assessing the effect of a fuel break network to reduce burnt area and wildfire risk transmission
Authors: Oliveira Tiago M. , Barros Ana M. G. , Ager Alan A. , Fernandes Paulo M.
Published: May 2016

Wildfires pose complex challenges to policymakers and fire agencies. Fuel break networks and area-wide fuel treatments are risk-management options to reduce losses from large fires. Two fuel management scenarios covering 3% of the fire-prone Algarve region of Portugal and differing in the intensity of treatment in 120-m wide fuel breaks were examined and compared with the no-treatment option. We used the minimum travel time algorithm to simulate the growth of 150 000 fires under the weather conditions historically associated with large fires. Fuel break passive effects on burn probability, area burned, fire size distribution and fire transmission among 20 municipalities were analysed. Treatments decreased large-fire incidence and reduced overall burnt area up to 17% and burn probability between 4% and 31%, depending on fire size class and treatment option. Risk transmission among municipalities varied with community. Although fire distribution shifted and large events were less frequent, mean treatment leverage was very low (1 : 26), revealing a very high cost–benefit ratio and the need for engaging forest owners to act in complementary area-wide fuel treatments. The study assessed the effectiveness of a mitigating solution in a complex socioecological system, contributing to a better-informed wildland fire risk governance process among stakeholders.