bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phase-contrast zoom tomography reveals precise locations of macrophages in mouse lungs
Authors: Krenkel Martin , Markus Andrea , Bartels Matthias , Dullin Christian , Alves Frauke , Salditt Tim 
Published: May 2015

AbstractWe have performed x-ray phase-contrast tomography on mouse lung tissue. Using a divergent x-ray beam generated by nanoscale focusing, we used zoom tomography to produce three-dimensional reconstructions with selectable magnification, resolution and field of view. Thus, macroscopic tissue samples extending over several mm can be studied in sub-cellular-level structural detail. The zoom capability and, in particular, the high dose efficiency are enabled by the near-perfect exit wavefront of an optimized x-ray waveguide channel. In combination with suitable phase-retrieval algorithms, challenging radiation-sensitive and low-contrast samples can be reconstructed with minimal artefacts. The dose efficiency of the method is demonstrated by the reconstruction of living macrophages both with and without phagocytized contrast agents. We also used zoom tomography to visualize barium-labelled macrophages in the context of morphological structures in asthmatic and healthy mouse lung tissue one day after intratracheal application. The three-dimensional reconstructions showed that the macrophages predominantly localized to the alveoli, but they were also found in bronchial walls, indicating that these cells might be able to migrate from the lumen of the bronchi through the epithelium.
Large enhancement of superconducting transition temperature of SrBi3 induced by Na substitution for Sr
Authors: Iyo Akira , Yanagi Yousuke , Kinjo Tatsuya , Nishio Taichiro , Hase Izumi , Yanagisawa Takashi , Ishida Shigeyuki , Kito Hijiri , Takeshita Nao , Oka Kunihiko , Yoshida Yoshiyuki , Eisaki Hiroshi 
Published: May 2015

AbstractThe Matthias rule, which is an empirical correlation between the superconducting transition temperature (Tc) and the average number of valence electrons per atom (n) in alloys and intermetallic compounds, has been used in the past as a guiding principle to search for new superconductors with higher Tc. The intermetallic compound SrBi3 (AuCu3 structure) exhibits a Tc of 5.6 K. An ab-initio electronic band structure calculation for SrBi3 predicted that Tc increases on decreasing the Fermi energy, i.e., on decreasing n, because of a steep increase in the density of states. In this study, we demonstrated that high-pressure (~ 3 GPa) and low-temperature ( < 350 °C) synthesis conditions enables the substitution of Na for about 40 at.% of Sr. With a consequent decrease in n, the Tc of (Sr,Na)Bi3 increases to 9.0 K. A new high-Tc peak is observed in the oscillatory dependence of Tc on n in compounds with the AuCu3 structure. We have shown that the oscillatory dependence of Tc is in good agreement with the band structure calculation. Our experiments reaffirm the importance of controlling the number of electrons in intermetallic compounds.
Structural basis for epitope masking and strain specificity of a conserved epitope in an intrinsically disordered malaria vaccine candidate
Authors: Morales Rodrigo A. V. , MacRaild Christopher A. , Seow Jeffrey , Krishnarjuna Bankala , Drinkwater Nyssa , Rouet Romain , Anders Robin F. , Christ Daniel , McGowan Sheena , Norton Raymond S. 
Published: May 2015

AbstractMerozoite surface protein 2 (MSP2) is an intrinsically disordered, membrane-anchored antigen of the malaria parasite Plasmodium falciparum. MSP2 can elicit a protective, albeit strain-specific, antibody response in humans. Antibodies are generated to the conserved N- and C-terminal regions but many of these react poorly with the native antigen on the parasite surface. Here we demonstrate that recognition of a conserved N-terminal epitope by mAb 6D8 is incompatible with the membrane-bound conformation of that region, suggesting a mechanism by which native MSP2 escapes antibody recognition. Furthermore, crystal structures and NMR spectroscopy identify transient, strain-specific interactions between the 6D8 antibody and regions of MSP2 beyond the conserved epitope. These interactions account for the differential affinity of 6D8 for the two allelic families of MSP2, even though 6D8 binds to a fully conserved epitope. These results highlight unappreciated mechanisms that may modulate the specificity and efficacy of immune responses towards disordered antigens.
Chromosome microduplication in somatic cells decreases the genetic stability of human reprogrammed somatic cells and results in pluripotent stem cells
Authors: Yu Yang , Chang Liang , Zhao Hongcui , Li Rong , Fan Yong , Qiao Jie 
Published: May 2015

AbstractHuman pluripotent stem cells, including cloned embryonic and induced pluripotent stem cells, offer a limitless cellular source for regenerative medicine. However, their derivation efficiency is limited and a large proportion of cells are arrested during reprogramming. In the current study, we explored chromosome microdeletion/duplication in arrested and established reprogrammed cells. Our results show that aneuploidy induced by somatic cell nuclear transfer technology is a key factor in the developmental failure of cloned human embryos and primary colonies from implanted cloned blastocysts and that expression patterns of apoptosis-related genes are dynamically altered. Overall, ~20%–53% of arrested primary colonies in induced plurpotent stem cells displayed aneuploidy and upregulation of P53 and Bax occurred in all arrested primary colonies. Interestingly, when somatic cells with pre-existing chromosomal mutations were used as donor cells, no cloned blastocysts were obtained and additional chromosomal mutations were detected in the resulting iPS cells following long-term culture, which was not observed in the two iPS cell lines with normal karyotypes. In conclusion, aneuploidy induced by the reprogramming process restricts the derivation of pluripotent stem cells, and, more importantly, pre-existing chromosomal mutations enhance the risk of genome instability, which limits the clinical utility of these cells.
Hierarchical Nanostructures Self-Assembled from a Mixture System Containing Rod-Coil Block Copolymers and Rigid Homopolymers
Authors: Li Yongliang , Jiang Tao , Lin Shaoliang , Lin Jiaping , Cai Chunhua , Zhu Xingyu 
Published: May 2015

AbstractSelf-assembly behavior of a mixture system containing rod-coil block copolymers and rigid homopolymers was investigated by using Brownian dynamics simulations. The morphologies of formed hierarchical self-assemblies were found to be dependent on the Lennard-Jones (LJ) interaction εRR between rod blocks, lengths of rod and coil blocks in copolymer and mixture ratio of block copolymers to homopolymers. As the εRR value decreases, the self-assembled structures of mixtures are transformed from an abacus-like structure to a helical structure, to a plain fiber and finally are broken into unimers. The order parameter of rod blocks was calculated to confirm the structure transition. Through varying the length of rod and coil blocks, the regions of thermodynamic stability of abacus, helix, plain fiber and unimers were mapped. Moreover, it was discovered that two levels of rod block ordering exist in the helices. The block copolymers are helically wrapped on the homopolymer bundles to form helical string, while the rod blocks are twistingly packed inside the string. In addition, the simulation results are in good agreement with experimental observations. The present work reveals the mechanism behind the formation of helical (experimentally super-helical) structures and may provide useful information for design and preparation of the complex structures.
Early land use and centennial scale changes in lake-water organic carbon prior to contemporary monitoring
Authors: Meyer-Jacob Carsten , Tolu Julie , Bigler Christian , Yang Handong , Bindler Richard 
Published: May 2015

Significance
Monitoring programs have recorded increases in organic carbon concentrations in northern lakes, which have important implications for water quality and ecosystem functioning. Current hypotheses interpret this trend in light of recent environmental changes such as acidification and climate but do not include an examination of long-term changes and their causes. We inferred past trends from sediment archives across central Sweden, allowing us to assess recent changes on a millennial scale. Our data demonstrate that a long-term decline beginning already in the 15th century preceded the recent organic carbon increase. This was a response to spatially extensive human–landscape interactions that included forest grazing and mire exploitation, which were common across Europe and altered carbon cycling between terrestrial and aquatic ecosystems.
Imaging metabolite dynamics in living cells using a Spinach-based riboswitch
Authors: You Mingxu , Litke Jacob L. , Jaffrey Samie R. 
Published: May 2015

Significance
Developing sensors to image cellular metabolites and signaling molecules in living cells is challenging. Here we describe Spinach riboswitches, a novel class of genetically encoded metabolite sensor based on riboswitches, a group of naturally occurring ligand-binding RNAs. Spinach riboswitches use Spinach, an RNA aptamer that binds and activates the fluorescence of an otherwise nonfluorescent small-molecule fluorophore. Drawing upon structural insights into the mechanism of structural switching in riboswitches, we show that Spinach can be swapped into various riboswitches, allowing metabolite binding to induce Spinach fluorescence directly. Expression of Spinach riboswitches in cells allows metabolite levels to be imaged in real time in live bacterial cells. Spinach riboswitches thus provide a novel approach to image cellular metabolites in living cells.
MYC oncogene overexpression drives renal cell carcinoma in a mouse model through glutamine metabolism
Authors: Shroff Emelyn H. , Eberlin Livia S. , Dang Vanessa M. , Gouw Arvin M. , Gabay Meital , Adam Stacey J. , Bellovin David I. , Tran Phuoc T. , Philbrick William M. , Garcia-Ocana Adolfo , Casey Stephanie C. , Li Yulin , Dang Chi V. , Zare Richard N. , Felsher Dean W. 
Published: May 2015

Significance
The absence of appropriate transgenic animal models of renal cell carcinomas (RCCs) has made it difficult to identify and test new therapies for this disease. We developed a new transgenic mouse model of a highly aggressive form of RCC in which tumor growth and regression is conditionally regulated by the MYC oncogene. Using desorption electrospray ionization–mass-spectrometric imaging, we found that certain glycerophosphoglycerols and metabolites of the glutaminolytic pathway were higher in abundance in RCC than in normal kidney tissue. Up-regulation of glutaminolytic genes and proteins was identified by genetic analysis and immunohistochemistry, therefore suggesting that RCC tumors are glutamine addicted. Pharmacological inhibition of glutaminase slowed tumor progression in vivo, which may represent a novel therapeutic route for RCC.
Superradiant Instability of D-Dimensional Reissner—Nordström Black Hole Mirror System*
Authors: Li Ran , Zhao Jun-Kun , Zhang Yan-Ming 
Published: May 2015

Abstract
We analytically study the superradiant instability of charged massless scalar field in the background of D-dimensional Reissner-Nordström (RN) black hole caused by mirror-like boundary condition. By using the asymptotic matching method to solve the Klein-Gordon equation that governs the dynamics of scalar field, we have derived the expressions of complex parts of boxed quasinormal frequencies, and shown they are positive in the regime of superradiance. This indicates the charged scalar field is unstable in D-dimensional Reissner-Nordström (RN) black hole surrounded by mirror. However, the numerical work to calculate the boxed quasinormal frequencies in this system is still required in the future.
High Efficiency Four-Wave Mixing with Relaxation Coupling of Longitude-Optical Phonons in Semiconductor Quantum Wells*
Authors: She Yan-Chao , Zheng Xue-Jun , Wang Deng-Long , Ding Jian-Wen 
Published: May 2015

Abstract
The time-dependent analysis of four-wave mixing (FWM) has been performed in four-level double semiconductor quantum wells (SQWs) considering the cross-coupling of the longitude-optical phonons (LOP) relaxation. It is shown that both the amplitude and the conversion efficiency of the FWM field enhance greatly with the increasing strength of cross-coupling of LOP relaxation. Interestingly, a double peak value of the conversion efficiency is obtained under a relatively weak single-photon detuning considering the LOP coupling. When the detuning becomes stronger, the double peaks turn into one peak appearing at the line respect to the about equality two control fields. The results can be interpreted by the effect of electromagnetically induced transparency and the indirect transition. Such controlled high efficiency FWM based on the cross-coupling LOP may have potential applications in quantum control and communications.
Structural and Interaction Properties of Porphyrin Layers — A Quantum Chemical Study
Authors: Praveena G. , Abiram A. 
Published: May 2015

Abstract
This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used NO, CO, and O2 diatomic molecules to interact with the porphyrin layers. The most common Fe-centered metalloporphyrin structure with tetra-pyrrlic rings having N4 core is chosen for the study. The optimization of Porphyrin-Porphyrin (PI-PII) and Porphyrin-Diatomic molecule-Porphyrin (PI-AB-PII) (AB = NO, CO, and O2) complexes are performed using HF method. In order to understand the planarity and appropriate stacking size of porphyrins and also to infer the separation of diatomic molecules between porphyrin layers the behavior of PI-AB-PII complexes (where AB = NO, CO, and O2) are analyzed using structural properties and molecular electrostatic potentials (MEP). The MEPs are calculated using hybrid exchange correlation functional B3PW91 of DFT along with 6-31+G* basis set for the PI-PII and PI-AB-PII complexes obtained from HF method.
Cytoskeleton Dynamics: A Continuum Cooperative Hydrolysis Model*
Authors: Xu Jian-Wei , Cheng Bo , Feng Yu-Yu , Wang Zi-Qing , Wang Guo-Dong 
Published: May 2015

Abstract
Cytoskeleton is a network of filamentous proteins, such as actin filaments and microtubules. We propose a continuum cooperative hydrolysis model which possesses exactly analytical solution to describe the dynamics of filament. The results show that the cooperativity leads to non negative-exponential distribution of T (ATP or GTP) subunits. As an application, we investigate the treadmilling phenomenon using our model. It is shown that the cooperativity remarkably affects the length of filament.
Imaging on a sphere with interferometers: the spherical wave harmonic transform
Authors: Carozzi T. D. 
Published: May 2015

Abstract
I present an exact and explicit solution to the scalar (Stokes flux intensity) radio interferometer imaging equation on a spherical surface which is valid also for non-coplanar interferometer configurations. This imaging equation is comparable to w-term imaging algorithms, but by using a spherical rather than a Cartesian formulation this term has no special significance. The solution presented also allows direct identification of the scalar (spin 0 weighted) spherical harmonics on the sky. The method should be of interest for future multispacecraft interferometers, wide-field imaging with non-coplanar arrays, and cosmic microwave background spherical harmonic measurements using interferometers.
Two bright z &gt; 6 quasars from VST ATLAS and a new method of optical plus mid-infrared colour selection
Authors: Carnall A. C. , Shanks T. , Chehade B. , Fumagalli M. , Rauch M. , Irwin M. J. , Gonzalez-Solares E. , Findlay J. R. , Metcalfe N. 
Published: May 2015

Abstract
We present the discovery of two z &gt; 6 quasars, selected as i-band dropouts in the Very Large Telescope Survey Telescope ATLAS survey. Our first quasar has redshift, z = 6.31 ± 0.03, z-band magnitude, zAB = 19.63 ± 0.08 and rest frame 1450 Å absolute magnitude, M1450 = −27.8 ± 0.2, making it the joint second most luminous quasar known at z &gt; 6. The second quasar has z = 6.02 ± 0.03, zAB = 19.54 ± 0.08 and M1450 = −27.0 ± 0.1. We also recover a z = 5.86 quasar discovered by Venemans et al., in preparation. To select our quasars, we use a new 3D colour space, combining the atlas optical colours with mid-infrared data from the Wide-field Infrared Survey Explorer. We use iAB − zAB colour to exclude main-sequence stars, galaxies and lower redshift quasars, W1 − W2 to exclude L dwarfs and zAB − W2 to exclude T dwarfs. A restrictive set of colour cuts returns only our three high redshift quasars and no contaminants, albeit with a sample completeness of ∼50 per cent. We discuss how our 3D colour space can be used to reject the majority of contaminants from samples of bright 5.7 &lt; z &lt; 6.3 quasars, replacing follow-up near-infrared photometry, whilst retaining high completeness.
Violent intranight optical variability of the blazar S4 0954+65 during its unprecedented 2015 February outburst
Authors: Bachev Rumen 
Published: May 2015

Abstract
In this letter, we present results from intranight monitoring in three colours (BRI) of the blazar S4 0954+65 during its recent (2015 February) unprecedented high state. We find violent variations on very short time-scales, reaching magnitude change levels of 0.1–0.2 mag h−1. On some occasions, changes of ∼0.1 mag are observed even within ∼10 min. During the night of 2015 February 14, an exponential drop of ∼0.7 mag is detected for about 5 h. Cross-correlation between the light curves does not reveal any detectable wavelength-dependent time delays, larger than ∼5 min. Colour changes ‘bluer-when-brighter’ are observed on longer time-scales. Possible variability mechanisms to explain the observations are discussed and a preference to the geometrical one is given.
Financial development, economic growth and millennium development goals in South Africa
Authors: Akinboade Oludele Akinloye , Kinfack Emilie Chanceline 
Published: May 2015

Purpose– The purpose of this paper is to empirically report the findings on the relationship between financial sector development, economic growth and of millennium development goals (MDGs) for poverty reduction, education and health development in South Africa.Design/methodology/approach– The autoregressive distributed lag bounds testing technique was applied to two indicators of financial development, economic growth and four indicators of MDGs.Findings– Economic growth and MDGs jointly cause financial development. Similarly, economic growth and financial sector development jointly cause the attainment of MDGs. The attainment of MDGs such as increased per capita expenditure on food and education as well as economic growth jointly cause financial development.Practical implications– The findings highlight the complexity of the relationship between financial development, economic growth and MDGs. It is essential that the government of South Africa pursue a three track strategy of promoting financial sector development, economic growth and MDGs. The development of one strategy causes and is caused by the development of the other two.Originality/value– Relationships between financial development, economic growth and MDG targets are unsettled in the literature. This paper studies the link between the three variables in South Africa. Hence, the contribution of this study is to enrich the understanding of this important field in the context of an important African country.
Context matters: general practice and social work – the Birmingham story
Authors: Lotinga Alan 
Published: May 2015

Purpose
– The purpose of this paper is to describe the approach adopted to building relationships between health and social care in Birmingham.

Design/methodology/approach
– This is a practical case study, reflecting on personal experience of being directly involved in the situations and discussions described. It supplements a 2012 paper (Lotinga and Glasby, 2012) on the creation of Birmingham’s Health and Well-being Board.

Findings
– Local history and context is crucial in shaping the nature of local joint working initiatives – understanding where local services have come from and why they have made the choices they have is a crucial pre-requisite for understanding current and future opportunities.

Research limitations/implications
– This paper aims to place joint working between general practice and social work in a broader organisational, financial and policy setting – and placing local developments in this wider context is crucial for understanding barriers and opportunities locally.

Originality/value
– In the absence of a detailed evidence base, front-line practice is often far ahead of the current research evidence. This means that local case studies like this are crucial in terms of sharing learning with other areas of the country, with policy makers and with researchers. While many case studies of joint working are small in nature, Birmingham is the largest local authority in Europe – so this paper also contributes learning based on trying to develop joint working in very large, complex authorities.
Knowing me, knowing you
Authors: Mangan Catherine , Miller Robin , Ward Carol 
Published: May 2015

Purpose
– The purpose of this paper is to report on the findings of the first stage of a project seeking to improve interprofessional working between general practice and adult social care teams. It develops the current evidence base through findings from focus groups and reflects on the implications of the findings for interprofessional collaboration.

Design/methodology/approach
– The project involved running seven focus groups with general practice staff and adult social work teams to explore their perceptions and understanding of each other.

Findings
– The focus groups highlighted that the negative aspects of interprofessional working outweighed the positives. Negatives included perceptions of different value bases, a lack of knowledge about each others’ roles and responsibilities which resulted in resorting to stereotypes, poor interprofessional communication and a sense of an unspoken professional hierarchy with general practitioners (GPs) at the top leading preventing a culture of appropriate challenge.

Research limitations/implications
– The research has only been conducted with four GP practices and three social work teams that had expressed an interest in improving their interprofessional working. Therefore the findings may not be generalisable.

Practical implications
– The case study suggests that there is a lack of effective interprofessional working between social care teams and general practice. With the current health and social care agenda focused on integration, this suggests there should be a greater focus on this area.

Originality/value
– This paper illustrates that despite many years of policy makers promoting better integration, the quality of the interprofessional collaboration between social care teams and general practice remains poor.