bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid and noncontact photoacoustic tomography imaging system using an interferometer with high-speed phase modulation technique
Authors: Liu Jun , Tang Zhilie , Wu Yongbo , Wang Yi
Published: April 2015

We designed, fabricated, and tested a rapid and noncontact photoacoustic tomography (PAT) imaging system using a low-coherence interferometer with high-speed phase modulation technique. Such a rapid and noncontact probing system can greatly decrease the time of imaging. The proposed PAT imaging system is experimentally verified by capturing images of a simulated tissue sample and the blood vessels within the ear flap of a mouse (pinna) in vivo. The axial and lateral resolutions of the system are evaluated at 45 and ∼15 μm, respectively. The imaging depth of the system is 1 mm in a special phantom. Our results show that the proposed system opens a promising way to realize noncontact, real-time PAT.
Characteristics and mechanism study of cerium oxide based random access memories
Authors: Hsieh Cheng-Chih , Roy Anupam , Rai Amritesh , Chang Yao-Feng , Banerjee Sanjay K.
Published: April 2015

In this work, low operating voltage and high resistance ratio of different resistance states of binary transition metal oxide based resistive random access memories (RRAMs) are demonstrated. Binary transition metal oxides with high dielectric constant have been explored for RRAM application for years. However, CeOx is considered as a relatively new material to other dielectrics. Since research on CeOx based RRAM is still at preliminary stage, fundamental characteristics of RRAM such as scalability and mechanism studies need to be done before moving further. Here, we show very high operation window and low switching voltage of CeOx RRAMs and also compare electrical performance of Al/CeOx/Au system between different thin film deposition methods and discuss characteristics and resistive switching mechanism.
Crossover between weak anti-localization and weak localization by Co doping and annealing in gapless PbPdO2 and spin gapless Co-doped PbPdO2
Authors: Choo S. M. , Lee K. J. , Park S. M. , Yoon J. B. , Park G. S. , You C.-Y. , Jung M. H.
Published: April 2015

The magnetotransport properties of Pb(Pd,Co)O2 and PbPdO2 thin films were investigated. In magnetoconductance curves, we observed a crossover between weak anti-localization (WAL) and weak localization (WL) depending on the annealing and Co doping in PbPdO2 thin films. For the Pb(Pd,Co)O2 case showing WAL signals, the ex-situ annealing weakens the Pd-O hybridization by stabilizing Co3+ states and generating Pd1+ states, instead of Pd2+, so that the spin-orbit coupling (SOC) strength is significantly reduced. It causes the dominant magnetotransport mechanism change from WAL to WL. This annealing effect is compared with the PbPdO2 case, which possesses WL signals. The annealing process stabilizes the oxygen states and enhances the Pd-O hybridization, and consequently the SOC strength is enhanced. Our experimental results are well explained by the Hikami-Larkin-Nagaoka theory in terms of two important physical parameters; SOC strength-related α and inelastic scattering length lϕ.
Nanocrystalline Si/SiO2 core-shell network with intense white light emission fabricated by hot-wire chemical vapor deposition
Authors: Matsumoto Y. , Dutt A. , Santana-Rodríguez G. , Santoyo-Salazar J. , Aceves-Mijares M.
Published: April 2015

We report the fabrication of a stable Si/SiO2 core-shell network using hot-wire chemical vapor deposition on a silicon substrate at a relatively low substrate temperature of 200 °C. Structural investigations using transmission electron microscopy and X-ray diffraction confirm the presence of nanocrystalline silicon and silicon dioxide quantum dots in the form of a core-shell network embedded in the amorphous SiOx matrix, while selected area electron diffraction confirms the formation of a core-shell structure. The core-shell structure exhibits a bright white emission that can be seen with the unaided eye at room temperature without any post-annealing treatments, and the observed photoemission does not alter in color or intensity after prolonged laser exposure. Additional measurements are performed while varying the laser power and optical gain is found in the as-deposited material. Intense stable white luminescence is observed and shows the prospective for various optical and biological applications in the future.
Multiple semiclassical states for coupled Schrödinger-Poisson equations with critical exponential growth
Authors: Liu Zhisu , Guo Shangjiang , Fang Yanqin
Published: April 2015

In this paper, we study the multiplicity of positive solutions for a class of Schrödinger-Poisson systems. Working in a variational setting, we prove the existence and multiplicity of positive solutions for the system when the Plank’s constant is small and the potential satisfies some suitable conditions. We show that the number of positive solutions depends on the profile of the potential and that each solution concentrates around its corresponding global minimum point of the potential in the semi-classical limit. We also study the exponential decay.
The temperature-dependent diffusion coefficient of helium in zirconium carbide studied with first-principles calculations
Authors: Yang Xiao-Yong , Lu Yong , Zhang Ping
Published: April 2015

The temperature-dependent diffusion coefficient of interstitial helium in zirconium carbide (ZrC) matrix is calculated based on the transition state theory. The microscopic parameters in the activation energy and prefactor are obtained from first-principles total energy and phonon frequency calculations including the all atoms. The obtained activation energy is 0.78 eV, consistent with experimental value. Besides, we evaluated the influence of C and Zr vacancies as the perturbation on helium diffusion, and found the C vacancy seems to confine the mobility of helium and the Zr vacancy promotes helium diffusion in some extent. These results provide a good reference to understand the behavior of helium in ZrC matrix.
Charge-mediated influence of the antibody variable domain on FcRn-dependent pharmacokinetics
Authors: Schoch Angela , Kettenberger Hubert , Mundigl Olaf , Winter Gerhard , Engert Julia , Heinrich Julia , Emrich Thomas
Published: April 2015

Significance

Therapeutic antibodies of the immunoglobulin G (IgG) isotype show a pharmacokinetic (PK) profile that is strongly mediated by the interaction with the neonatal Fc receptor (FcRn). Therefore, modulating the FcRn–IgG interaction allows altering PK characteristics of therapeutic antibodies. So far, engineering the crystallizable fragment (Fc) is known to affect PK, and, although the influence of the antigen binding fragment (Fab) on FcRn interactions has been reported, the underlying mechanism remains unknown. Here, we demonstrate that the charge distribution in the distal variable fragment (Fv) of IgGs is involved in excessive binding to the FcRn, thereby reducing FcRn-dependent terminal half-lives in vivo. These findings contribute to a better understanding of the FcRn–IgG interaction.
Operationalizing the social-ecological systems framework to assess sustainability
Authors: Leslie Heather M. , Basurto Xavier , Nenadovic Mateja , Sievanen Leila , Cavanaugh Kyle C. , Cota-Nieto Juan José , Erisman Brad E. , Finkbeiner Elena , Hinojosa-Arango Gustavo , Moreno-Báez Marcia , Nagavarapu Sriniketh , Reddy Sheila M. W. , Sánchez-Rodríguez Alexandra , Siegel Katherine , Ulibarria-Valenzuela José Juan , Weaver Amy Hudson , Aburto-Oropeza Octavio
Published: April 2015

Significance

Meeting human needs while sustaining ecosystems and the benefits they provide is a global challenge. Coastal marine systems present a particularly important case, given that >50% of the world’s population lives within 100 km of the coast and fisheries are the primary source of protein for >1 billion people worldwide. Our integrative analysis here yields an understanding of the sustainability of coupled social-ecological systems that is quite distinct from that provided by either the biophysical or the social sciences alone and that illustrates the feasibility and value of operationalizing the social-ecological systems framework for comparative analyses of coupled systems, particularly in data-poor and developing nation settings.
Functional connectivity arises from a slow rhythmic mechanism
Authors: Li Jingfeng M. , Bentley William J. , Snyder Lawrence H.
Published: April 2015

Significance

Functional connectivity MRI has revolutionized our understanding of brain architecture. Correlated changes in oxygen levels reveal networks of regions. These networks, each linked to particular functions, are conserved across individuals and species. Normal development, learning, and mental disorders are associated with subtle network changes, providing insight into how brains work. Remarkably, the basis of functional connectivity remains unknown. Although some studies have reported data consistent with an oscillatory process, the leading hypothesis involves emergent, arrhythmic dynamics of complex and distributed networks (the “criticality” hypothesis). By using a new electrode-based technique, we show that functional connectivity is not related to criticality, but instead to specific and potentially localizable oscillatory processes. This finding provides a tool to identify the mechanisms underlying functional connectivity.
Predator lipids induce paralytic shellfish toxins in bloom-forming algae
Authors: Selander Erik , Kubanek Julia , Hamberg Mats , Andersson Mats X. , Cervin Gunnar , Pavia Henrik
Published: April 2015

Significance

We report the chemical basis for a critical question in ocean science: how do single-celled algae, which are responsible for almost half of Earth's photosynthesis, sense their environment to respond appropriately to the lethal threat of predation? The increasing frequency of toxic algal blooms, with worldwide consequences to human health, fisheries, and marine ecosystem functioning, has garnered much attention in recent years, but it has remained unclear how algal toxicity is regulated. With the current paper, we show that substantial (20×) induction of toxicity occurs when one species of algae is exposed to a family of previously unknown chemical cues from predatory zooplankton (copepods). The copepodamides represent the first discovery, to our knowledge, of chemical cues mediating interactions between marine zooplankton and their prey.
Reconciling reported and unreported HFC emissions with atmospheric observations
Authors: Lunt Mark F. , Rigby Matthew , Ganesan Anita L. , Manning Alistair J. , Prinn Ronald G. , O’Doherty Simon , Mühle Jens , Harth Christina M. , Salameh Peter K. , Arnold Tim , Weiss Ray F. , Saito Takuya , Yokouchi Yoko , Krummel Paul B. , Steele L. Paul , Fraser Paul J. , Li Shanlan , Park Sunyoung , Reimann Stefan , Vollmer Martin K. , Lunder Chris , Hermansen Ove , Schmidbauer Norbert , Maione Michela , Arduini Jgor , Young Dickon , Simmonds Peter G.
Published: April 2015

Significance

Hydrofluorocarbons (HFCs) are among the atmosphere’s fastest growing, and most potent, greenhouse gases. Proposals have been made to phase down their use over the coming decades. Such initiatives may largely be informed by existing emissions inventories, which, we show, are the subject of significant uncertainty. In this work, we use atmospheric models and measurements to examine the accuracy of these inventories for five major HFCs. We show that, when aggregated together, reported emissions of these HFCs from developed countries are consistent with the atmospheric measurements, and almost half of global emissions now originate from nonreporting countries. However, the agreement between our results and the inventory breaks down for individual HFC emissions, suggesting inaccuracies in the reporting methods for individual compounds.
Cas9-mediated targeting of viral RNA in eukaryotic cells
Authors: Price Aryn A. , Sampson Timothy R. , Ratner Hannah K. , Grakoui Arash , Weiss David S.
Published: April 2015

Significance

The clustered, regularly interspaced, short palindromic repeats associated endonuclease, Cas9, has quickly become a revolutionary tool in genome engineering. Utilizing small guiding RNAs, Cas9 can be targeted to specific DNA sequences of interest, where it catalyzes DNA cleavage. We now demonstrate that Cas9 from the Gram-negative bacterium
Francisella novicida
(FnCas9) can be reprogrammed to target a specific RNA substrate, the genome of the +ssRNA virus, hepatitis C virus, in eukaryotic cells. Further, this targeting results in inhibition of viral protein production. Overall, programmable Cas9-mediated viral RNA targeting likely represents one of myriad potential applications of FnCas9 in RNA targeting in eukaryotic cells.
Genetic differences and aberrant methylation in the apelin system predict the risk of high-altitude pulmonary edema
Authors: Mishra Aastha , Kohli Samantha , Dua Sanchi , Thinlas Tashi , Mohammad Ghulam , Pasha M. A. Qadar
Published: April 2015

Significance

Exposure to a high-altitude (HA) hypobaric hypoxia environment produces physiological changes. Among these, the changes in the apelin signaling system are significant because this system regulates vascular and oxygen homeostasis. This study demonstrates that the HA environment stimulates the apelin system to distinguish genetic variants and the methylation profile of CpG islands that may impair or improve pulmonary vascular function, thereby resulting in HA pulmonary edema (HAPE) in patients or adaptation in healthy controls. Of the several variants of this system,
apelin
rs3761581
G
and rs2235312
T
, individually and in combination, and a greater methylation of a CpG island in the 5′ UTR, associated with low levels of apelin-13 and nitrite in HAPE, whereas a reverse trend was observed in the control groups.
Synaptic abnormalities and cytoplasmic glutamate receptor aggregates in contactin associated protein-like 2
/Caspr2
knockout neurons
Authors: Varea Olga , Martin-de-Saavedra Maria Dolores , Kopeikina Katherine J. , Schürmann Britta , Fleming Hunter J. , Fawcett-Patel Jessica M. , Bach Anthony , Jang Seil , Peles Elior , Kim Eunjoon , Penzes Peter
Published: April 2015

Significance

In this paper, we characterize, for the first time to our knowledge, synaptic phenotypes in contactin associated protein-like 2 (
Cntnap2
) knockout neurons and reveal a novel role for CNTNAP2 in the correct trafficking of AMPA-type glutamate receptors. In addition, we report that cellular phenotypes emerge late in postnatal development, suggesting a mechanism for the apparent late emergence of some
CNTNAP2
-associated disorders. Taken together, our findings may provide insight into the mechanism underlying pathogenesis of
CNTNAP2
-associated neuropsychiatric disorders.
Contribution of air conditioning adoption to future energy use under global warming
Authors: Davis Lucas W. , Gertler Paul J.
Published: April 2015

Significance

The use of air conditioning is poised to increase dramatically over the next several decades as global temperatures go up and incomes rise around the world. In this paper, we use high-quality microdata from Mexico to characterize empirically the relationship between temperature, income, and air conditioning. We describe both how electricity consumption increases with temperature given current levels of air conditioning, and how climate and income drive air conditioning adoption decisions. We then combine these estimates with predicted end-of-century temperature changes to forecast future energy consumption. Overall, our results point to air conditioning impacts being considerably larger than previously believed.
Diabetes-associated dysregulation of
O
-GlcNAcylation in rat cardiac mitochondria
Authors: Banerjee Partha S. , Ma Junfeng , Hart Gerald W.
Published: April 2015

Significance

Mitochondrial dysfunction contributes significantly to glucose toxicity in diabetes. Increased
O
-GlcNAcylation is emerging as a major molecular cause of glucose toxicity via many mechanisms. The studies herein provide a direct molecular link between hyperglycemia and mitochondrial dysfunction. We show that mitochondrial
O
-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) expression levels and localizations are strikingly different between normal and diabetic rat hearts. We also discover how UDP-GlcNAc enters the mitochondrial space. Finally our data demonstrate that OGT and OGA play significant roles in ATP production, mitochondrial membrane potential, and oxygen consumption. These studies are of general interest not only with respect to nutrient regulation of mitochondrial function, but also are important to elucidate mechanisms of diabetic complications.
Solution structure of the PsIAA4 oligomerization domain reveals interaction modes for transcription factors in early auxin response
Authors: Dinesh Dhurvas Chandrasekaran , Kovermann Michael , Gopalswamy Mohanraj , Hellmuth Antje , Calderón Villalobos Luz Irina A. , Lilie Hauke , Balbach Jochen , Abel Steffen
Published: April 2015

Significance

Indole-3-acetic acid (IAA or auxin) is indispensable during the entire plant life cycle and regulates diverse processes and transitions via hierarchical gene expression. The hormone triggers rapid destruction of AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) repressors that control AUXIN RESPONSE FACTOR (ARF) activators in auxin-regulated gene transcription. AUX/IAA and ARF proteins interact physically via their C-terminal Phox and Bem1p (PB1) domain, which is shared between both families. This work reports the solution structure of a wild-type AUX/IAA PB1 domain and identifies amino acid residues that engage in directional interaction of monomers, largely via hydrogen bonds between conserved basic and acidic surface patches. Our study provides a framework for unraveling molecular determinants that confer specificity to complex interactions between AUX/IAA and ARF transcription factors.
Functional reconstitution ofDrosophila melanogasterNMJ glutamate receptors
Authors: Han Tae Hee , Dharkar Poorva , Mayer Mark L. , Serpe Mihaela
Published: April 2015

Significance

We report the first functional reconstitution of neuromuscular (NMJ) glutamate receptors from the fruit flyDrosophila. The identification of these receptors enabled tremendous insight into the mechanisms of synapse assembly and development. However, analysis of animals with mutant receptors is complicated by compound phenotypes; studies on isolated receptors are necessary to identify the structural elements and auxiliary proteins important for receptor assembly, surface delivery, and function. We show that Neto is an essential component required for the function ofDrosophilaNMJ receptors expressed inXenopusoocytes, and use this system to examine subunit dependence and function. We find thatDrosophilaNMJ receptors have ligand-binding properties and structural features strikingly different from vertebrate glutamate receptors.
Microscopic identification of the order parameter governing liquid–liquid transition in a molecular liquid
Authors: Murata Ken-ichiro , Tanaka Hajime
Published: April 2015

Significance

Liquid–liquid transition (LLT) in single-component liquids is one of the most mysterious phenomena in condensed matter. To understand this phase transition, it is essential to elucidate the order parameter governing it. We have succeeded in accessing the structural order parameter governing LLT by simultaneously measuring small- and wide-angle X-ray scattering during the process of LLT. We identify the order parameter to be the number density of locally favored structures, whose size is a few nanometers. This suggests that the order parameter is scalar and nonconserved. This finding sheds new light on the physical nature of this unconventional transition from one liquid to another.
Assortative mating without assortative preference
Authors: Xie Yu , Cheng Siwei , Zhou Xiang
Published: April 2015

Significance

Assortative mating, the tendency of men and women who marry to have similar social characteristics, is a commonly observed phenomenon in human societies. This study shows that assortative mating could result from structural causes independent of human agents’ preference, because unmarried persons who newly enter marriage are systematically different from those who married earlier. Thus, assortative mating could result from selection, not by rational choice, but by the dynamics of social structures.
MurJ and a novel lipid II flippase are required for cell wall biogenesis inBacillus subtilis
Authors: Meeske Alexander J. , Sham Lok-To , Kimsey Harvey , Koo Byoung-Mo , Gross Carol A. , Bernhardt Thomas G. , Rudner David Z.
Published: April 2015

Significance

The bacterial envelope is composed of a diverse set of polysaccharides. Virtually all of these polymers are synthesized from lipid-linked precursors that are flipped across the cytoplasmic membrane by ATP-binding cassette transporters or multidrug/oligosaccharidyl-lipid/polysaccharide (MOP) exporter superfamily members. Transport of the cell wall precursor lipid II requires the MOP family member MurJ inEscherichia coli. Here, we provide evidence for a novel lipid II flippase inBacillus subtiliscalled alternate to MurJ (Amj), which bears no similarity to either family of transporters.amjis up-regulated in the absence ofB. subtilisMurJ (MurJBs) via an envelope stress-response pathway, suggesting this novel flippase may serve as a defense mechanism against naturally occurring MurJ antagonists.
Topology, structures, and energy landscapes of human chromosomes
Authors: Zhang Bin , Wolynes Peter G.
Published: April 2015

Significance

Various cell types emerge from their nearly identical genetic content for a multicellular organism, in part, via the regulation of the function of the genome—the DNA molecules inside the cell. Similar to the way catalytic activity is lost when proteins denature, the function of the genome is tightly coupled to its 3D organization. A theoretical framework for picturing the structure and dynamics of the genome will therefore greatly advance our understanding of cell biology. We present an energy landscape model of the chromosome that reproduces a diverse set of experimental measurements. The model enables quantitative predictions of chromosome structure and topology and provides mechanistic insight into the role of 3D genome organization in gene regulation and cell differentiation.
Characterizing the in vivo role of trehalose inSaccharomyces cerevisiaeusing theAGT1transporter
Authors: Gibney Patrick A. , Schieler Ariel , Chen Jonathan C. , Rabinowitz Joshua D. , Botstein David
Published: April 2015

Significance

Trehalose is an important molecule for industrial and medical applications. These applications include use as a food additive to increase sweetness and promote freeze-dry preservation. Trehalose is also included in antibody preparations for stabilization during freezing or desiccation. Further, trehalose biosynthesis is required for virulence of fungal pathogens, and, because animal cells do not synthesize trehalose, trehalose biosynthesis is an attractive antifungal target. Despite all of its uses, the direct physiological roles of trehalose remain unclear. Here, we describe the development and characterization of a system in the model yeastSaccharomyces cerevisiaeto directly assess the physiological roles of trehalose. We find that many of the roles traditionally ascribed to trehalose are not the result of trehalose accumulation per se.
Transatlantic Networks in the Correspondence of Two Exiled Spanish Musicians, Julián Bautista and Adolfo Salazar
Authors: Moreda Rodríguez Eva
Published: April 2015

Studies of the Spanish Republican exile, both musicological and otherwise, have often worked under the assumption that the exiles were disconnected from Francoist Spain and were thus unable to contribute in any way to the musical life of their home country. This article re-examines these assumptions by analysing a hitherto unexplored corpus of correspondence between two exiled musicians, Julián Bautista and Adolfo Salazar, and other musicians who had stayed in Francoist Spain. Such correspondence suggests that the exiles could, and indeed did, contribute to Spanish musical life under Francoism in a variety of ways.
Thomas Adès and the Spectres of Brahms
Authors: Venn Edward
Published: April 2015

The appearance of a ghost in Alfred Brendel's poem ‘Brahms II’, set by Thomas Adès for baritone and orchestra in 2001, is not the first time Brahms the composer has been discussed with reference to the supernatural. In order to provide a hermeneutic interpretation of Adès's Brahms, op. 21, and an explanation of why Brahms continues to haunt composers of the twentieth and twenty-first centuries, this article draws on Derrida's notion of hauntology, exploring notions of the uncanny, late Brahms and Schoenberg's ‘Brahms the Progressive’.
Right Ventricular Remodeling in Idiopathic and Scleroderma‐Associated Pulmonary Arterial Hypertension: Two Distinct Phenotypes
Authors: Kelemen Benjamin W. , Mathai Stephen C. , Tedford Ryan J. , Damico Rachel L. , Corona‐Villalobos Cecilia , Kolb Todd M. , Chaisson Neal F. , Harris Traci Housten , Zimmerman Stefan L. , Kamel Ihab R. , Kass David A. , Hassoun Paul M.
Published: April 2015

Patients with scleroderma (SSc)–associated pulmonary arterial hypertension (PAH) have worse survival than patients with idiopathic PAH (IPAH). We hypothesized that the right ventricle (RV) adapts differently in SSc‐PAH versus IPAH. We used cardiac magnetic resonance imaging (cMRI) and hemodynamic characteristics to assess the relationship between RV morphology and RV load in patients with SSc‐PAH and IPAH. In 53 patients with PAH (35 with SSc‐PAH and 18 with IPAH) diagnosed by right heart catheterization (RHC), we examined cMRIs obtained within 48 hours of RHC and compared RV morphology between groups. Regression analysis was used to assess the association between diagnosis (IPAH vs. SSc‐PAH) and RV measurements after adjusting for age, sex, race, body mass index (BMI), left ventricular (LV) mass, and RV load. There were no significant differences in unadjusted comparisons of cMRI measurements between the two groups. Univariable regression showed RV mass index (RVMI) was linearly associated with measures of RV load in both the overall cohort and within each group. Multivariable linear regression models revealed a significant interaction between disease type and RVMI adjusting for pulmonary vascular resistance (PVR), age, sex, race, BMI, and LV mass. This model showed a decreased slope in the relationship between RVMI and PVR in the SSc‐PAH group compared with the IPAH group. RVMI varies linearly with measures of RV load. After adjusting for multiple potential confounders, patients with SSc‐PAH demonstrated significantly less RV hypertrophy with increasing PVR than patients with IPAH. This difference in adaptive hypertrophy may in part explain previously observed decreased contractility and poorer survival in SSc‐PAH.
Case Series of 5 Patients with End‐Stage Renal Disease with Reversible Dyspnea, Heart Failure, and Pulmonary Hypertension Related to Arteriovenous Dialysis Access
Authors: Raza Farhan , Alkhouli Mohamad , Rogers Frances , Vaidya Anjali , Forfia Paul
Published: April 2015

Patients with end‐stage renal disease (ESRD) with arteriovenous dialysis access (AVDA) can develop symptoms of heart failure and pulmonary hypertension (PH). We report on 5 patients with ESRD and AVDA who presented with shortness of breath, heart failure, and PH. All patients had partial or complete closure of AVDA and were reevaluated after AVDA revision. All 5 subjects had clinical and echocardiographic evidence of heart failure, hypertensive heart disease, left ventricular diastolic dysfunction, and PH at baseline. After complete closure (n = 4) or partial banding (n = 1) of AVDA, mean New York Heart Association class improved from 3.4 ± 0.4 to 1.8 ± 0.4 (P = 0.016). Mean 6‐minute walk distance improved from 236 ± 115 to 366 ± 51 m (P = 0.021). Serial echocardiography revealed a decrease in the right ventricle: left ventricle ratio from 1.12 ± 0.17 to 0.8 ± 0.06 (P = 0.005) and improved diastolic dysfunction parameters. On right heart catheterization before definitive AVDA revision, acute manual fistula or graft occlusion led to an average decrease in cardiac output of 1.1 L/min with no other changes in hemodynamics: 9.88 ± 2.2 to 8.71 ± 2.2 L/min (P = 0.059). However, the average decrease in cardiac output after definitive revision of the AVDA (mean, 90 days) was 4.0 L/min with marked improvements in biventricular filling pressures and pulmonary artery pressure. In patients with ESRD and AVDA presenting with heart failure and PH, revision or closure of AVDA can markedly improve dyspnea as well as the clinical, echocardiographic, and hemodynamic manifestations of heart failure and PH.
Multidimensional stochastic differential equations with distributional drift
Authors: Flandoli Franco , Issoglio Elena , Russo Francesco
Published: April 2015

This paper investigates a time-dependent multidimensional stochastic differential equation with drift being a distribution in a suitable class of Sobolev spaces with negative derivation order. This is done through a careful analysis of the corresponding Kolmogorov equation whose coefficient is a distribution.
Redox-regulated dynamic interplay between Cox19 and the copper-binding protein Cox11 in the intermembrane space of mitochondria facilitates biogenesis of cytochromecoxidase
Authors: Bode Manuela , Woellhaf Michael W. , Bohnert Maria , Laan Martin van der , Sommer Frederik , Jung Martin , Zimmermann Richard , Schroda Michael , Herrmann Johannes M.
Published: April 2015

Members of the twin Cx9C protein family constitute the largest group of proteins in the intermembrane space (IMS) of mitochondria. Despite their conserved nature and their essential role in the biogenesis of the respiratory chain, the molecular function of twin Cx9C proteins is largely unknown. We performed a SILAC-based quantitative proteomic analysis to identify interaction partners of the conserved twin Cx9C protein Cox19. We found that Cox19 interacts in a dynamic manner with Cox11, a copper transfer protein that facilitates metalation of the Cu(B) center of subunit 1 of cytochrome c oxidase. The interaction with Cox11 is critical for the stable accumulation of Cox19 in mitochondria. Cox19 consists of a helical hairpin structure that forms a hydrophobic surface characterized by two highly conserved tyrosine-leucine dipeptides. These residues are essential for Cox19 function and its specific binding to a cysteine-containing sequence in Cox11. Our observations suggest that an oxidative modification of this cysteine residue of Cox11 stimulates Cox19 binding, pointing to a redox-regulated interplay of Cox19 and Cox11 that is critical for copper transfer in the IMS and thus for biogenesis of cytochrome c oxidase.
Structural basis for the catalytic mechanism of homoserine dehydrogenase
Authors: Navratna Vikas , Reddy Govardhan , Gopal Balasubramanian
Published: April 2015

Homoserine dehydrogenase (HSD) is an oxidoreductase in the aspartic acid pathway. This enzyme coordinates a critical branch point of the metabolic pathway that leads to the synthesis of bacterial cell-wall components such as L-lysine andm-DAP in addition to other amino acids such as L-threonine, L-methionine and L-isoleucine. Here, a structural rationale for the hydride-transfer step in the reaction mechanism of HSD is reported. The structure ofStaphylococcus aureusHSD was determined at different pH conditions to understand the basis for the enhanced enzymatic activity at basic pH. An analysis of the crystal structure revealed that Lys105, which is located at the interface of the catalytic and cofactor-binding sites, could mediate the hydride-transfer step of the reaction mechanism. The role of Lys105 was subsequently confirmed by mutational analysis. Put together, these studies reveal the role of conserved water molecules and a lysine residue in hydride transfer between the substrate and the cofactor.
The solvent component of macromolecular crystals
Authors: Weichenberger Christian X. , Afonine Pavel V. , Kantardjieff Katherine , Rupp Bernhard
Published: April 2015

The mother liquor from which a biomolecular crystal is grown will contain water, buffer molecules, native ligands and cofactors, crystallization precipitants and additives, various metal ions, and often small-molecule ligands or inhibitors. On average, about half the volume of a biomolecular crystal consists of this mother liquor, whose components form the disordered bulk solvent. Its scattering contributions can be exploited in initial phasing and must be included in crystal structure refinement as a bulk-solvent model. Concomitantly, distinct electron density originating from ordered solvent components must be correctly identified and represented as part of the atomic crystal structure model. Herein, are reviewed (i) probabilistic bulk-solvent content estimates, (ii) the use of bulk-solvent density modification in phase improvement, (iii) bulk-solvent models and refinement of bulk-solvent contributions and (iv) modelling and validation of ordered solvent constituents. A brief summary is provided of current tools for bulk-solvent analysis and refinement, as well as of modelling, refinement and analysis of ordered solvent components, including small-molecule ligands.
Corrigenda for four articles
Authors: Li Qiang
Published: April 2015

The acknowledgement text is corrected in four articles: Li, Wang & Ye [Acta Cryst.(2014), C70, 992–997], Li & Wang [Acta Cryst.(2014), C70, 1054–1056], Li [Acta Cryst.(2015), C71, 65–68] and Li, Wang & Zhou [Acta Cryst.(2015), C71, 93–96].
L-Argininium phosphite – a new candidate for NLO materials
Authors: Ghazaryan Vahram V. , Zakharov Boris A. , Petrosyan Aram M. , Boldyreva Elena V.
Published: April 2015

In order to investigate the possibility of salt formation in the L-Arg–H3PO3–H2O system, single crystals of L-argininium phosphite, C6H15N4O2+·H2PO3−, were prepared by evaporation of an aqueous solution containing equimolar quantities of L-arginine and phosphorous acid. The asymmetric unit contains one L-argininium(+) cation and one phosphite [HPO2(OH)]−anion. The phosphite anions form chains parallel to [010] by O—H...O hydrogen bonding, with an O...O distance of 2.630 (3) Å. The protonated amine and guanidyl groups of the L-argininium(+) cations form N—H...O hydrogen bonds with the carboxylate groups and anions. The IR and Raman spectra are discussed in relation to the crystal structure. The salt displays nonlinear optical (NLO) properties. Another salt was obtained from a solution with a 1:2 molar ratio of components, but was characterized by vibrational spectra only.
Schedule preferences, congruence and employee outcomes in unionized shift workers
Authors: Wittmer Jenell L.S. , Shepard Agnieszka K , Martin James E.
Published: April 2015

Purpose

– Employees working nonstandard schedules outside the daytime hours of the Monday-Friday work week are increasing. Using Social Exchange Theory (SET), the purpose of this paper is to hypothesize relationships between scheduling preferences, attitudes, and retention indicators.

Design/methodology/approach

– Survey data were collected from 343 US Postal Service mail processors (day, evening, or night shift; all shifts working weekends) from three cities. Multivariate analysis of covariance and multiple linear regression were used to test hypotheses related to participants’ perceptions of scheduling preferences and attitudes.

Findings

– The authors found that preferences and attitudes toward shift worked had stronger relationships with each other and employee retention indicators for the night and evening shifts than the day shift, and these same relationships were stronger for the day shift when focussing on days of the week worked.

Research limitations/implications

– Although limited by generalizability concerns, this study provides a distinctive application of SET to work schedules and offers a unique perspective on how working nonstandard days and nonstandard times, individually, impact the employment relationship.

Practical implications

– Better work schedule management, with increased flexibility and control, may be one way of reducing negative employee reactions to nonstandard schedules.

Originality/value

– This study goes beyond the typical examinations of standard vs nonstandard shifts, to study multiple nonstandard shifts and examines the relationships of these schedules on employee retention variables, focussing on both shift and weekend work.
The impact of banks’ entrepreneurial orientation on strategic control systems
Authors: Callaway Stephen K. , Jagani Sandeep B.
Published: April 2015

Purpose

– An organization’s entrepreneurial orientation will relate directly to its efficiency strategies, market development strategies (growth), and its product development strategies (innovation). A firm will develop appropriate strategic control systems according to these chosen strategies. In order to be competitive and balance efficiency, growth and innovation strategies, the purpose of this paper is to discuss the most appropriate strategic controls to implement these strategies.

Design/methodology/approach

– The eight variables under study were measured using 22 psychometric survey items obtained from responses of 101 FDIC-registered banks.

Findings

– The results show a more entrepreneurial orientation is associated with an efficiency strategy, a market development strategy, and a product development strategy. The efficiency strategy was not associated with formal controls, contrary to expectations. A market development strategy was associated with formal rules, but was not found to be associated with formal targets. Finally, product development strategies was associated with all four strategic control archetypes.

Research limitations/implications

– The limitation of this study is that, it only examined banking institutions, and did not consider long-term financial performance implications. This paper supports and extends current research pertaining to company key success factors. Success requires effectively balancing cost reduction objectives, growth objectives, and innovation objectives, in order to achieve sustainable competitive advantage. A more entrepreneurial orientation necessitates a focus on innovation, traditional growth patterns, as well as cost cutting.

Originality/value

– This paper demonstrates that an organization’s entrepreneurial orientation will relate directly to its efficiency, growth, and innovation strategies. Also, it finds the most effective strategic controls to implement these strategies.
How do you warn them if they speak only Spanish? Challenges for organizations in communicating risk to Colonias residents in Texas, USA
Authors: Arlikatti Sudha , A. Taibah Hassan , A. Andrew Simon
Published: April 2015

Purpose

– The purpose of this paper is to examine the information channels used by public and nonprofit organizations to communicate disaster risk information toColoniasresidents in Hidalgo County, Texas. It seeks to find creative and proactive solutions for organizations to improve risk education to these constituents.

Design/methodology/approach

– Initially a snowball sampling technique was used to conduct six face-to-face interviews. This was followed by an online survey sent to 64 reputational referrals, of which 23 completed the survey, generating a response rate of 34 percent. A comparative analysis between public and nonprofit organizations and the Fischer's exact test were employed to analyze the data.

Findings

– Channel preferences for providing risk information varied with public organizations using the television (TV) and the nonprofit organizations using bilingual staff for outreach. The television, radio, public events, and bilingual staff were considered to be the most effective while social media (Facebook, Twitter, and city web sites) was not considered at all by both groups. Lack of funding and staffing problems were identified as the primary challenges.

Research limitations/implications

– One limitation is that the paper focusses on organizations serving Spanish speakers in the TexasColonias. Future research needs to investigate how other localities at border sites where culturally and linguistically diverse groups might reside, receive and understand risk information. The role of cross-national organizations in creating internationally coordinated plans for disaster communication should also be explored.

Originality/value

– It highlights the challenges faced by organizations in communicating risk, especially in border communities where culturally and linguistically diverse groups reside.
Bridging the concepts of resilience, fragility and stabilisation
Authors: Manyena Siambabala Bernard , Gordon Stuart
Published: April 2015

Purpose

– The fragile states and stabilisation concepts appear to resonate with the concept of community resilience. Yet, there is barely a framework that integrates the three concepts. The authors posit that despite the increasing interest in community resilience in fragile states, there is much less clarity of resilience, fragility and stabilisation connections. The paper aims to discuss these issues.

Design/methodology/approach

– This paper is based on the literature review of the concepts of community resilience, fragility and stabilisation.

Findings

– The findings restate that the state fragility results from the breakdown of the social contract between the state and its citizens. Whilst both resilience and stabilisation are desirable constructs in reducing fragility, they should be broadly underpinned by agency not only to enhance preventive, anticipatory, absorptive and adaptive actions but also lead to social transformative capacity where agency is embedded for communities to exercise some sort of power to foster change.

Originality/value

– This paper has encourages debate on resilience, fragility and stabilisation connections by suggesting framework for “doing” resilience-informed stabilisation programmes in fragile states. The framework, which may not necessarily be approached in a linear fashion, has three major components: identifying existing resilience factors, enhancing and sustaining these and delivering resilient communities. However, there is need to test the utility of the framework in practice.
Contextualising typologies of environmentally induced population movement
Authors: Stojanov Robert , Kelman Ilan , Shen Shawn , Duží Barbora , Upadhyay Himani , Vikhrov Dmytro , Lingaraj G.J. , Mishra Arabinda
Published: April 2015

Purpose

– The purpose of this paper is to show how typologies for environmentally induced population movement need to be understood in a contextualised manner in order to be useful.

Design/methodology/approach

– This study interrogates some academic discourses concerning environmentally induced population movement. By analysing key environmental factors said to contribute to population movement, in addition to considering time factors, this study uses the case of Tuvalu to demonstrate overlapping categories and the importance of contextualisation.

Findings

– Current typologies provide a basis for considering a wide variety of motives for environmentally induced population movement, in relation to different drivers, motivations, time scales, and space scales. Yet contextualisation is required for policy and practice relevance.

Research limitations/implications

– All typologies have limitations. Any typology should be taken as a possible tool to apply in a particular context, or to support decision making, rather than presenting a typology as universal or as an absolute without dispute.

Practical implications

– Rather than disputes over typologies and definitions, bringing together different views without reconciling them, but recognising the merits and limitations of each, can provide a basis for assisting people making migration decisions.

Originality/value

– None of the typologies currently available applies to all contexts of environmentally induced population movement – nor should any single typology necessarily achieve that. Instead, it is important to thrive on the differences and to contextualise a typology for use.
Assessment of disaster risk management in Mexico
Authors: Saldana-Zorrilla Sergio  O.
Published: April 2015

Purpose

– The purpose of this paper is to provide a set of policy suggestions for integrating risk management and increasing risk reduction measures and planning.

Design/methodology/approach

– It bases on a brief description of the disaster risk management programs in Mexico, a review of their recent available assessments as well as it makes a brief economic analysis of their performance to conclude with some policy suggestions.

Findings

– Despite its novel design, the still low penetration of governmental instruments for disaster risk reduction in Mexico has led to high society’s reliance on post-disaster measures. It has encouraged moral risk among potential victims. Even when crop insurance has increased coverage over the past decade, disaster prevention instruments are still underused. Accessing to prevention funding requires project proposals from national and sub-national governments based on concrete risk assessments. However, the prevailing lack of institutional capacity to elaborate proposals from sub-national governments seems to explain it at a large extent. The paper provides a set of suggestions on this regard.

Originality/value

– There is no recent integral assessment of disaster risk in Mexico. Although there is a recent OECD review of the National Civil Protection System, its analysis leaves out the catastrophic agricultural insurance, critical part of comprehensive risk management of a country. On the other hand, there are recent evaluations of programs public for disaster risk management, but these consist of only individual program evaluations, lacking integrative and comparative analysis. Thus, this paper provides a comprehensive view of government risk management and concludes with a series of policy recommendations.
Developing the eventful city in Sibiu, Romania
Authors: Richards Greg , Rotariu Ilie
Published: April 2015

Purpose

– Cities are increasingly using events as an instrument for economic and social change and cultural and urban regeneration. Major events help cities to distinguish themselves, and attracting event-related tourism generates income and jobs and increases atmosphere and “liveliness”. Many cities have therefore positioned themselves as “eventful cities” or “festival cities” by adopting event-led strategies. The paper aims to discuss these issues.

Design/methodology/approach

– The effects of the 2007 European Capital of Culture (ECoC) in Sibiu, Romania were evaluated through a decade of longitudinal research including surveys and depth interviews with local residents, stakeholders and tourists to monitor the sustainability of event-related regeneration strategies.

Findings

– The impacts identified include increased cultural activity, tourism growth, image improvements and increased pride among residents. These impacts have been facilitated by a local growth coalition, and the increased linkage of the city to flows of investment, skills and talent through EU membership. The city has taken some important steps to becoming an “eventful city”, in which events are utilised to sustainably increase the quality of life. However, the momentum of eventfulness developed in 2007 has been difficult to maintain, and there are difficulties in separating the effect of event-related activities from wider cultural, social and economic development factors.

Originality/value

– The research indicates that the Sibiu ECoC in 2007 and the programme of cultural development leading up to it had substantial impacts on the city both in the short and longer term. The ECoC certainly met most of its short-term aims, as there was a significant economic boost from tourism and an improvement in the external image of the city.