bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resilience of electricity grids against transmission line overloads under wind power injection at different nodes
Authors: Schiel Christoph , Lind Pedro G. , Maass Philipp 
Published: September 2017

AbstractA steadily increasing fraction of renewable energy sources for electricity production requires a better understanding of how stochastic power generation affects the stability of electricity grids. Here, we assess the resilience of an IEEE test grid against single transmission line overloads under wind power injection based on the dc power flow equations and a quasi-static grid response to wind fluctuations. Thereby we focus on the mutual influence of wind power generation at different nodes. We find that overload probabilities vary strongly between different pairs of nodes and become highly affected by spatial correlations of wind fluctuations. An unexpected behaviour is uncovered: for a large number of node pairs, increasing wind power injection at one node can increase the power threshold at the other node with respect to line overloads in the grid. We find that this seemingly paradoxical behaviour is related to the topological distance of the overloaded line from the shortest path connecting the wind nodes. In the considered test grid, it occurs for all node pairs, where the overloaded line belongs to the shortest path.
Adaptive pixel-super-resolved lensfree in-line digital holography for wide-field on-chip microscopy
Authors: Zhang Jialin , Sun Jiasong , Chen Qian , Li Jiaji , Zuo Chao 
Published: September 2017

AbstractHigh-resolution wide field-of-view (FOV) microscopic imaging plays an essential role in various fields of biomedicine, engineering, and physical sciences. As an alternative to conventional lens-based scanning techniques, lensfree holography provides a new way to effectively bypass the intrinsical trade-off between the spatial resolution and FOV of conventional microscopes. Unfortunately, due to the limited sensor pixel-size, unpredictable disturbance during image acquisition, and sub-optimum solution to the phase retrieval problem, typical lensfree microscopes only produce compromised imaging quality in terms of lateral resolution and signal-to-noise ratio (SNR). Here, we propose an adaptive pixel-super-resolved lensfree imaging (APLI) method which can solve, or at least partially alleviate these limitations. Our approach addresses the pixel aliasing problem by Z-scanning only, without resorting to subpixel shifting or beam-angle manipulation. Automatic positional error correction algorithm and adaptive relaxation strategy are introduced to enhance the robustness and SNR of reconstruction significantly. Based on APLI, we perform full-FOV reconstruction of a USAF resolution target (~29.85 mm2) and achieve half-pitch lateral resolution of 770 nm, surpassing 2.17 times of the theoretical Nyquist–Shannon sampling resolution limit imposed by the sensor pixel-size (1.67µm). Full-FOV imaging result of a typical dicot root is also provided to demonstrate its promising potential applications in biologic imaging.
Outcomes of adjuvant epithelial growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment for EGFR-mutant non-small-cell lung cancer: a propensity-score analysis
Authors: Zhao Shufen , Ma Ge , Guo Jing , Ding Aiping , Wang Shasha , Yu Guohong , Chen Lei , Yuan Yonggang , Xiao Wenjing 
Published: September 2017

AbstractSmall molecule tyrosine kinase inhibitors (TKIs) have transformed the management of advanced non-small-cell lung cancer (NSCLC) harboring activating epithelial growth factor receptor (EGFR) mutations, while the efficacy of TKIs in the adjuvant setting remains unclear. We collected the data of 209 EGFR-mutant NSCLC patients receiving complete resection from 2010 to 2013. Study end points were disease-free survival (DFS) and overall survival (OS). Among the eligible patients, 41 (19.6%) received EGFR TKIs in the adjuvant treatment. The 3-year DFS of adjuvant EGFR TKIs treatment group (70.5%, 95% CI, 54.6–86.4%) was significantly superior that control group (50.2%, 95% CI, 40–60.4%; log-rank P = 0.014). TKIs treatment (HR, 0.51; 95% CI, 0.29–0.97; P = 0.04) was significantly associated with improved DFS in multivariate Cox analysis. No significant difference was observed in 3-year OS between two groups (73.1% [58.0–88.2%] vs 61.8% [52.2–71.4%], log-rank P = 0.21). Propensity-score matching further confirmed that adjuvant TKIs treatment extended the DFS (log-rank P = 0.024), but did not improve OS (log-rank P = 0.40). Our analysis revealed that adjuvant EGFR TKIs treatment was beneficial for early-stage NSCLC patients harboring activating EGFR mutations after complete resection.
Incoherent digital holograms acquired by interferenceless coded aperture correlation holography system without refractive lenses
Authors: Kumar Manoj , Vijayakumar A. , Rosen Joseph 
Published: September 2017

AbstractWe present a lensless, interferenceless incoherent digital holography technique based on the principle of coded aperture correlation holography. The acquired digital hologram by this technique contains a three-dimensional image of some observed scene. Light diffracted by a point object (pinhole) is modulated using a random-like coded phase mask (CPM) and the intensity pattern is recorded and composed as a point spread hologram (PSH). A library of PSHs is created using the same CPM by moving the pinhole to all possible axial locations. Intensity diffracted through the same CPM from an object placed within the axial limits of the PSH library is recorded by a digital camera. The recorded intensity this time is composed as the object hologram. The image of the object at any axial plane is reconstructed by cross-correlating the object hologram with the corresponding component of the PSH library. The reconstruction noise attached to the image is suppressed by various methods. The reconstruction results of multiplane and thick objects by this technique are compared with regular lens-based imaging.
Phylogenetic implications of nuclear rRNA IGS variation in Stipa L. (Poaceae)
Authors: Krawczyk Katarzyna , Nobis Marcin , Nowak Arkadiusz , Szczecińska Monika , Sawicki Jakub 
Published: September 2017

AbstractThe article takes up the problem of deficiency of molecular marker, which could illustrate molecular variability as well as phylogenetic relation within the genus of Stipa L. (Poaceae). Researches made so far hadn’t delivered sufficient information about relationships between particular taxa from the genus of Stipa. In the present study, we analyzed variability and phylogenetic informativeness of nuclear ribosomal DNA in six species from the genus against five other species from Poaceae including a division of this region into functional elements and domains. Our results showed that the intergenic spacer region, and especially its part adjacent to 26 S nrDNA, is a molecular marker giving a real chance for a phylogeny reconstruction of Stipa. The region seems to be the most phylogenetically informative for Stipa from all the chloroplast and nuclear markers tested so far. Comparative analysis of nrDNA repeat units from Stipa to other representatives of Poaceae showed that their structure does not deviate from the general scheme. However, the rate of evolution within the inter-repeats in the IGS region is extremely high and therefore it predestines the region for phylogenetic analyses of Stipa at genus level or in shallower taxonomic scale.
A Magnetometer Based on a Spin Wave Interferometer
Authors: Balynsky M. , Gutierrez D. , Chiang H. , Kozhevnikov A. , Dudko G. , Filimonov Y. , Balandin A. A. , Khitun A. 
Published: September 2017

AbstractWe describe a magnetic field sensor based on a spin wave interferometer. Its sensing element consists of a magnetic cross junction with four micro-antennas fabricated at the edges. Two of these antennas are used for spin wave excitation while two other antennas are used for detection of the inductive voltage produced by the interfering spin waves. Two waves propagating in the orthogonal arms of the cross may accumulate significantly different phase shifts depending on the magnitude and direction of the external magnetic field. This phenomenon is utilized for magnetic field sensing. The sensitivity attains its maximum under the destructive interference condition, where a small change in the external magnetic field results in a drastic increase of the inductive voltage, as well as in the change of the output phase. We report experimental data obtained for a micrometer scale Y3Fe2(FeO4)3 cross structure. The change of the inductive voltage near the destructive interference point exceeds 40 dB per 1 Oe. The phase of the output signal exhibits a π-phase shift within 1 Oe. The data are collected at room temperature. Taking into account the low thermal noise in ferrite structures, we estimate that the maximum sensitivity of the spin wave magnetometer may exceed attotesla.
Inhomogeneous phases in coupled electron-hole bilayer graphene sheets: Charge Density Waves and Coupled Wigner Crystals
Authors: Zarenia M. , Neilson D. , Peeters F. M. 
Published: September 2017

AbstractRecently proposed accurate correlation energies are used to determine the phase diagram of strongly coupled electron-hole graphene bilayers. The control parameters of the phase diagram are the charge carrier density and the insulating barrier thickness separating the bilayers. In addition to the electron-hole superfluid phase we find two new inhomogeneous ground states, a one dimensional charge density wave phase and a coupled electron-hole Wigner crystal. The elementary crystal structure of bilayer graphene plays no role in generating these new quantum phases, which are completely determined by the electrons and holes interacting through the Coulomb interaction. The experimental parameters for the new phases lie within attainable ranges and therefore coupled electron-hole bilayer graphene presents itself as an experimental system where novel emergent many-body phases can be realized.
Phosphorylation of Suppressor of Hairless impedes its DNA-binding activity
Authors: Nagel Anja C. , Auer Jasmin S. , Schulz Adriana , Pfannstiel Jens , Yuan Zhenyu , Collins Courtney E. , Kovall Rhett A. , Preiss Anette 
Published: September 2017

AbstractNotch signalling activity governs cellular differentiation in higher metazoa, where Notch signals are transduced by the transcription factor CSL, called Suppressor of Hairless [Su(H)] in Drosophila. Su(H) operates as molecular switch on Notch target genes: within activator complexes, including intracellular Notch, or within repressor complexes, including the antagonist Hairless. Mass spectrometry identified phosphorylation on Serine 269 in Su(H), potentially serving as a point of cross-regulation by other signalling pathways. To address the biological significance, we generated phospho-deficient [Su(H)S269A] and phospho-mimetic [Su(H)S269D] variants: the latter displayed reduced transcriptional activity despite unaltered protein interactions with co-activators and -repressors. Based on the Su(H) structure, Ser269 phosphorylation may interfere with DNA-binding, which we confirmed by electro-mobility shift assay and isothermal titration calorimetry. Overexpression of Su(H)S269D during fly development demonstrated reduced transcriptional regulatory activity, similar to the previously reported DNA-binding defective mutant Su(H)R266H. As both are able to bind Hairless and Notch proteins, Su(H)S269D and Su(H)R266H provoked dominant negative effects upon overexpression. Our data imply that Ser269 phosphorylation impacts Notch signalling activity by inhibiting DNA-binding of Su(H), potentially affecting both activation and repression. Ser269 is highly conserved in vertebrate CSL homologues, opening the possibility of a general and novel mechanism of modulating Notch signalling activity.
South Atlantic paleobathymetry since early Cretaceous
Authors: Pérez-Díaz Lucía , Eagles Graeme 
Published: September 2017

AbstractWe present early Cretaceous to present paleobathymetric reconstructions and quantitative uncertainty estimates for the South Atlantic, offering a strong basis for studies of paleocirculation, paleoclimate and paleobiogeography. Circulation in an initially salty and anoxic ocean, restricted by the topography of the Falkland Plateau, Rio Grande Ridge and Walvis Rise, favoured deposition of thick evaporites in shallow water of the Brazilian-Angolan margins. This ceased as seafloor spreading propagated northwards, opening an equatorial gateway to shallow and intermediate circulation. This gateway, together with subsiding volcano-tectonic barriers would have played a key role in Late Cretaceous climate changes. Later deepening and widening of the South Atlantic, together with gateway opening at Drake Passage would lead, by mid-Miocene (∼15 Ma) to the establishment of modern-style thermohaline circulation.
Bacteriological diagnosis of childhood TB: a prospective observational study
Authors: Brent Andrew J. , Mugo Daisy , Musyimi Robert , Mutiso Agnes , Morpeth Susan C. , Levin Michael , Scott J. Anthony G. 
Published: September 2017

AbstractChildhood TB diagnosis is challenging. Studies in adults suggest Microscopic Observation Drug Susceptibility (MODS) culture or the Xpert MTB/RIF assay might be used to expand bacteriological diagnosis. However data from children are more limited. We prospectively compared MODS and Xpert MTB/RIF with standard microscopy and culture using the BD MGIT 960 system among 1442 Kenyan children with suspected TB. 97 specimens from 54 children were TB culture-positive: 91 (94%) by MGIT and 74 (76%) by MODS (p = 0.002). 72 (74%) culture-positive and 7 culture-negative specimens were Xpert MTB/RIF positive. Xpert MTB/RIF specificity was 100% (99.7–100%) among 1164 specimens from 892 children in whom TB was excluded, strongly suggesting all Xpert MTB/RIF positives are true positives. The sensitivity of MGIT, MODS and Xpert MTB/RIF was 88%, 71% and 76%, respectively, among all 104 true positive (culture and/or Xpert MTB/RIF positive) specimens. MGIT, MODS and Xpert MTB/RIF on the initial specimen identified 40/51 (78%), 33/51 (65%) and 33/51 (65%) culture-confirmed pulmonary TB cases, respectively; Xpert MTB/RIF detected 5 additional culture-negative cases. The high sensitivity and very high specificity of the Xpert MTB/RIF assay supports its inclusion in the reference standard for bacteriological diagnosis of childhood TB in research and clinical practice.
Development of chloroplast genome resources for peanut (Arachis hypogaea L.) and other species of Arachis
Authors: Yin Dongmei , Wang Yun , Zhang Xingguo , Ma Xingli , He Xiaoyan , Zhang Jianhang 
Published: September 2017

AbsractPeanut (Arachis hypogaea L.) is an important oilseed and cash crop worldwide. WildArachisspp. are potental sources of novel genes for the genetic improvement of cultivated peanut. Understanding the genetic relationships with cultivated peanut is important for the efficient use of wild species in breeding programmes. However, for this genus, only a few genetic resources have been explored so far. In this study, new chloroplast genomic resources have been developed for the genusArachisbased on whole chloroplast genomes from seven species that were sequenced using next-generation sequencing technologies. The chloroplast genomes ranged in length from 156,275 to 156,395 bp, and their gene contents, gene orders, and GC contents were similar to those for other Fabaceae species. Comparative analyses among the seven chloroplast genomes revealed 643 variable sites that included 212 singletons and 431 parsimony-informative sites. We also identified 101 SSR loci and 85 indel mutation events. Thirty-seven SSR loci were found to be polymorphic byin silicocomparative analyses. Eleven highly divergent DNA regions, suitable for phylogenetic and species identification, were detected in the seven chloroplast genomes. A molecular phylogeny based on the complete chloroplast genome sequences provided the best resolution of the sevenArachisspecies.
Validating a therapy-oriented complication grading system in lumbar spine surgery: a prospective population-based study
Authors: Bellut David , Burkhardt Jan-Karl , Schultze Dania , Ginsberg Howard J , Regli Luca , Sarnthein Johannes 
Published: September 2017

AbstractThe aim of the present study was to validate a therapy-oriented complication grading system in a well-defined neurosurgical patient population in which complications may entrain neurological deficits, which are severe but not treated. The prospective patient registry of the Department of Neurosurgery, University of Zurich provides extensive population-based data. In this study we focused on complications after lumbar spine surgeries and rated their severity by Clavien-Dindo grade (CDG). Analyzing 138 consecutive surgeries we noted 44 complications. As to treatment, CDG correlated with the length of hospital stay and treatment cost. As to patient outcome, CDG correlated with performance and outcome (McCormick). The present study demonstrates the correlation between outcome scales and the CDG. While the high correlation of CDG with costs seems self-evident, the present study shows this correlation for the first time. Furthermore, the study validates the CDG for a surgical subspecialty. As a further advantage, CDG registers any deviation from the normal postoperative course and allows comparison between surgical specialties.
The ClpXP protease is dispensable for degradation of unfolded proteins in Staphylococcus aureus
Authors: Stahlhut Steen G. , Alqarzaee Abdulelah A. , Jensen Camilla , Fisker Niclas S. , Pereira Ana R. , Pinho Mariana G. , Thomas Vinai Chittezham , Frees Dorte 
Published: September 2017

AbstractIn living cells intracellular proteolysis is crucial for protein homeostasis, and ClpP proteases are conserved between eubacteria and the organelles of eukaryotic cells. In Staphylococcus aureus, ClpP associates to the substrate specificity factors, ClpX and ClpC forming two ClpP proteases, ClpXP and ClpCP. To address how individual ClpP proteases impact cell physiology, we constructed a S. aureus mutant expressing ClpX with an I265E substitution in the ClpP recognition tripeptide of ClpX. This mutant cannot degrade established ClpXP substrates confirming that the introduced amino acid substitution abolishes ClpXP activity. Phenotypic characterization of this mutant showed that ClpXP activity controls cell size and is required for growth at low temperature. Cells expressing the ClpXI265E variant, in contrast to cells lacking ClpP, are not sensitive to heat-stress and do not accumulate protein aggregates showing that ClpXP is dispensable for degradation of unfolded proteins in S. aureus. Consistent with this finding, transcriptomic profiling revealed strong induction of genes responding to protein folding stress in cells devoid of ClpP, but not in cells lacking only ClpXP. In the latter cells, highly upregulated loci include the urease operon, the pyrimidine biosynthesis operon, the betA-betB operon, and the pathogenicity island, SaPI5, while virulence genes were dramatically down-regulated.
Rapid alignment of nanotomography data using joint iterative reconstruction and reprojection
Authors: Gürsoy Doğa , Hong Young P. , He Kuan , Hujsak Karl , Yoo Seunghwan , Chen Si , Li Yue , Ge Mingyuan , Miller Lisa M. , Chu Yong S. , De Andrade Vincent , He Kai , Cossairt Oliver , Katsaggelos Aggelos K. , Jacobsen Chris 
Published: September 2017

AbstractAs x-ray and electron tomography is pushed further into the nanoscale, the limitations of rotation stages become more apparent, leading to challenges in the alignment of the acquired projection images. Here we present an approach for rapid post-acquisition alignment of these projections to obtain high quality three-dimensional images. Our approach is based on a joint estimation of alignment errors, and the object, using an iterative refinement procedure. With simulated data where we know the alignment error of each projection image, our approach shows a residual alignment error that is a factor of a thousand smaller, and it reaches the same error level in the reconstructed image in less than half the number of iterations. We then show its application to experimental data in x-ray and electron nanotomography.
What Does the Future Hold for Scientific Journals? Visual Abstracts and Other Tools for Communicating Research
Authors: Nikolian Vahagn , Ibrahim Andrew 
Published: September 2017

AbstractJournals fill several important roles within academic medicine, including building knowledge, validating quality of methods, and communicating research. This section provides an overview of these roles and highlights innovative approaches journals have taken to enhance dissemination of research. As journals move away from print formats and embrace web-based content, design-centered thinking will allow for engagement of a larger audience. Examples of recent efforts in this realm are provided, as well as simplified strategies for developing visual abstracts to improve dissemination via social media. Finally, we hone in on principles of learning and education which have driven these advances in multimedia-based communication in scientific research.
Bleeding and Thrombotic Complications in the Use of Extracorporeal Membrane Oxygenation
Authors: Thomas James , Kostousov Vadim , Teruya Jun 
Published: September 2017

AbstractExtracorporeal membrane oxygenation (ECMO) has been used for >40 years to support lung and heart failure; however, bleeding and thrombosis remain serious complications. The known etiologies of bleeding include heparin effect or overdose, coagulopathy, thrombocytopenia, platelet dysfunction, acquired von Willebrand syndrome, and hyperfibrinolysis. Bleeding sites may include cannula insertion sites, recent surgical incisions, vascular access sites, lung, gastrointestinal tract, mouth, nose, thoracic cavity, abdominal cavity, and brain. Massive bleeding in the brain, the most feared bleeding complication, can be rapidly fatal because it occurs in a rigid closed space, is difficult to drain, and cannot be stopped with direct pressure to the bleeding site. Pulmonary hemorrhage may cause irreversible lung damage. Management should be swift and precise to prevent fatal bleeding. In contrast, etiologies of thrombosis include high fibrinogen and factor VIII levels, heparin resistance, and platelet activation. Achieving the optimal anticoagulation balance to prevent bleeding and thrombosis in ECMO patients is extremely complex. Experts in hemostasis should be a part of an institutional ECMO team and continuously available for immediate management.