bluuebunny/crossref_metadata_2025 huggingface dataset:
Luminescent liquid crystals bearing an aggregation-induced emission active tetraphenylthiophene fluorophore
Authors: Guo Ling-Xiang , Xing Yi-Bo , Wang Meng , Sun Ying , Zhang Xue-Qin , Lin Bao-Ping , Yang Hong
Published: March 2019

In this work, six novel luminescent liquid crystal materials bearing an aggregation-induced emission active tetraphenylthiophene fluorophore are described.
Unprecedented 30 K hysteresis across switchable dielectric and magnetic properties in a bright luminescent organic–inorganic halide (CH6N3)2MnCl4
Authors: Sen Abhijit , Swain Diptikanta , Guru Row Tayur N. , Sundaresan A.
Published: March 2019

Highly luminescent hybrid (CH6N3)2MnCl4 featuring unique (Mn3Cl12)6− units in the crystal structure, exhibits a remarkable 30 K hysteresis across dielectric and magnetic switching.
One-step chemical treatment to design an ideal nanospacer structure for a highly sensitive and transparent pressure sensor
Authors: Woo Ho Kun , Kim Haneun , Jeon Sanghyun , Lee Woo Seok , Ahn Junhyuk , Bang Junsung , Kang Min Su , Oh Soong Ju
Published: March 2019

An ideal open meshed structure for a highly sensitive and transparent pressure sensor is simply fabricated by one-step chemical treatment.
ECRG4 acts as a tumor suppressor gene frequently hypermethylated in human breast cancer
Authors: Tang Gao-Yan , Tang Guo-Jun , Yin Lu , Chao Chen , Zhou Ren , Ren Guo-Ping , Chen Jia-Yu , Zhang Wei
Published: March 2019

Human breast cancer is a malignant form of tumor with a relatively high mortality rate. Although esophageal cancer-related gene 4 (ECRG4) is thought to be a possible potent tumor suppressor gene that acts to suppress breast cancer, its precise role in this disease is not understood. Herein, we assess the correlation between ECRG4 expression and DNA methylation, probing the potential epigenetic regulation of ECRG4 in breast cancer. We analyzed ECRG4 promoter methylation via methylation-specific PCR (MSPCR), bisulfite sequencing, and a promoter reporter assay in human breast cancer cell lines and samples. Gene expression was assessed by quantitative real-time PCR (qPCR), while protein levels were assessed by Western blotting. CCK8 assays were used to quantify cell growth; Esophageal cancer-related gene 4 wound healing assays were used to assess cellular migration, while flow cytometry was used to assess apoptosis and cell cycle progression. Apoptosome formation was validated via CO-IP and Western blotting. We found that human breast cancer samples exhibited increased methylation of the ECRG4 promoter and decreased ECRG4 expression. Remarkably, the down-regulation of ECRG4 was highly associated with promoter methylation, and its expression could be re-activated via 5-aza-2′-deoxycytidine treatment to induce demethylation. ECRG4 overexpression impaired breast cancer cell proliferation and migration, and led to G0/G1 cell cycle phase arrest. Moreover, ECRG4 induced the formation of the Cytc/Apaf-1/caspase-9 apoptosome and promoted breast cancer cell apoptosis. ECRG4 is silenced in human breast cancer cells and cell lines, likely owing to promoter hypermethylation. ECRG4 may act as a tumor suppressor, inhibiting proliferation and migration, inducing G0/G1 phase arrest and apoptosis via the mitochondrial apoptotic pathway.
DOA/MoM‐based ABF algorithm for SINR enhancement
Authors: Dawood Heba S. , Hussein Amr Hussein , Gemeay Entesar , Attia Mahmoud Ahmed
Published: March 2019

In this study, a new non‐iterative adaptive beamforming (ABF) algorithm for the signal‐to‐interference and noise ratio (SINR) enhancement is proposed. It is based on a combination between the direction of arrival (DOA) estimation and the method of moments (MoM). The proposed algorithm is denoted as DM/ABF which stands for DOA and MoM‐based ABF. The DOA is used to provide accurate estimates for the directions of the desired and interfering signals. On the basis of the estimated DOAs, a dedicated shaped pattern version of the ordinary pattern is created and applied as the desired input to the MoM algorithm. The MoM is used for shaped pattern synthesis to estimate the weights vector required to provide deep nulls toward the interfering signals and directs the main beam toward the desired signal. In this case, the weights vector does not update iteratively at each received signal sample as in case of least mean square (LMS) and recursive least squares (RLSs) algorithms, but it is updated only when the estimated DOAs of the desired and interfering signals are changed. Furthermore, a large number of close nulls can be produced without the need for additional antenna elements compared with other algorithms.
Pedestrian detection framework based on magnetic regional regression
Authors: Yao Li , Wang Bofan
Published: March 2019

In recent years, pedestrian detection has become one of the core issues in self‐driving car and automatic alert in video surveillance. However, the efficiency and accuracy are not ideal in multi‐pedestrian scenarios because of the occlusion by other pedestrian or non‐human objects. Here, the authors design a pedestrian‐detection framework based on region proposal network and convolutional neural network. Magnetic region regression strategy was proposed to reduce locating errors and false detection in the process of region regression. Meanwhile, semantic segmentation is integrated into authors’ framework to improve the accuracy of classification. Additionally, the authors used soft‐ non‐maximum suppression (NMS) to reduce the impact of NMS threshold on the model. Authors’ framework has average miss rate of 6.94% on Improved Caltech‐USA dataset. The experiments show that authors’ framework achieves significant advantages.
New strategy for CBIR by combining low‐level visual features with a colour descriptor
Authors: Unar Salahuddin , Wang Xingyuan , Wang Chunpeng , Wang Mingxu
Published: March 2019

In computer vision, the analysis of image contents plays a significant role to perform intelligent tasks such as object recognition and image retrieval. These contents can be low‐level visual features or colour information within an image. For content‐based image retrieval (CBIR), several methods have been proposed that focus on either low‐level visual features extraction or the colour information, and very few works can be seen that retrieve the images by fusing both types of contents. Consequently, this work addresses the problem of combining low‐level visual features with colour information that helps to improve the retrieval accuracy of CBIR. The proposed strategy extracts the low‐level visual salient features with features from accelerated segment test feature descriptor and quantises the salient keypoints into a feature vector. The colour information of the image is extracted and segmented with non‐linear L*a*b* colour space and quantised into a feature vector. The similarity for both the feature vectors including visual and colour features is computed and combined together. The top‐rank images are retrieved for the obtained feature vector using the distance metric. The experimental results on two standard benchmark datasets show the improved efficiency and 85% accuracy of the proposed strategy over state‐of‐the‐art methods.
Pietra index based processor for a heterogeneous Pareto background
Authors: Mehanaoui Ali , Laroussi Toufik , Mezache Amar
Published: March 2019

This study addresses the problem of automatic target detection in a heterogeneous Pareto background. To achieve this, the Pietra index based and constant false alarm rate processor (CFAR) is conceived. Specifically, assuming a non‐stationary Pareto background with the presence or not of any clutter edge or interfering targets, the Pietra index and the log geometric mean ratio statistic tests are concomitantly used to allow the proposed processor to switch dynamically to the appropriate detector; i.e. the geometric mean‐CFAR, the greatest of‐CFAR or the trimmed mean‐CFAR, where all of these detectors assume a priori unknown scale parameter. That is, according to the outcomes of the Window Selection Probability, the background level is systematically estimated through the preselected detector. The detection performances of the proposed processor are assessed, via Monte Carlo simulations, in multiple target and clutter edge situations.
Hydrothermal synthesis of 3D hierarchical flower‐like CuGaO2 with high surface area for dye‐sensitised solar cell
Authors: Ursu Daniel , Vajda Melinda , Miclau Marinela
Published: March 2019

CuGaO2 has been receiving much attention due to its potential as photocathode instead of NiO for p‐type dye sensitised solar cells (p ‐DSSCs). The improvement in the photovoltaic performance of such devices also depends on the increase of the efficient dye loading by significant enhanced specific surface areas. This work reports for the first time the fabrication of the three‐dimensional (3D) hierarchical flower‐like CuGaO2 nanostructures in a high uniformity by a facile one‐step hydrothermal synthesis. The growth mechanism and the effects of the reaction parameters (time and reducing agent) on the formation of the 3D hierarchical flower‐like CuGaO2 nanostructures were investigated in detailed. It is significantly to note that the prepared 3D hierarchical flower‐like CuGaO2 nanostructures exhibit the highest specific surface areas reported (60 m2/g with ethylene glycol). Due to the efficient dye loading by high specific surface areas, the performance of p ‐DSSCs based on delafossite CuGaO2 is enhanced. Thereby, based on the optical investigation, electrochemical impedance measurement and Mott–Schottky plots, the improved performance can be attributed to high loading of the dye molecules, the enhanced light‐scattering and the reduced interface recombination.
Precise radial velocities of giant stars
Authors: Reichert Katja , Reffert Sabine , Stock Stephan , Trifonov Trifon , Quirrenbach Andreas
Published: March 2019

Context. Radial-velocity variations of the K giant star Aldebaran (α Tau) were first reported in the early 1990s. After subsequent analyses, the radial-velocity variability with a period of ∼629 d has recently been interpreted as caused by a planet of several Jovian masses.

Aims. We want to further investigate the hypothesis of an extrasolar planet around Aldebaran.

Methods. We combine 165 new radial-velocity measurements from Lick Observatory with seven already published data sets comprising 373 radial-velocity measurements. We perform statistical analyses and investigate whether a Keplerian model properly fits the radial velocities. We also perform a dynamical stability analysis for a possible two-planet solution. Furthermore, the possibility of oscillatory convective modes as cause for the observed radial-velocity variability is discussed.

Results. As best Keplerian fit to the combined radial-velocity data we obtain an orbit for the hypothetical planet with a smaller period (P = 607 d) and a larger eccentricity (e = 0.33 ± 0.04) than the previously proposed one. However, the residual scatter around that fit is still large, with a standard deviation of 117 ms−1. In 2006/2007, the statistical power of the ∼620 d period showed a temporary but significant decrease. Plotting the growth of power in reverse chronological order reveals that a period around 620 d is clearly present in the newest data but not in the data taken before ∼2006. Furthermore, an apparent phase shift between radial-velocity data and orbital solution is observable at certain times. A two-planet Keplerian fit matches the data considerably better than a single-planet solution, but poses severe dynamical stability issues.

Conclusions. The radial-velocity data from Lick Observatory do not further support but in fact weaken the hypothesis of a substellar companion around Aldebaran. Oscillatory convective modes might be a plausible alternative explanation of the observed radial-velocity variations.
LMC S154: the first Magellanic symbiotic recurrent nova
Authors: Iłkiewicz Krystian , Mikołajewska Joanna , Miszalski Brent , Gromadzki Mariusz , Monard Berto , Amigo Pía
Published: March 2019

Classical nova outburst has been suggested for a number of extragalactic symbiotic stars, but in none of the systems has it been proven. In this work we study the nature of one of these systems, LMC S154. We gathered archival photometric observations in order to determine the timescales and nature of variability in this system. Additionally we carried out photometric and spectroscopic monitoring of the system and fitted synthetic spectra to the observations. Carbon abundance in the photosphere of the red giant is significantly higher than that derived for the nebula, which confirms pollution of the circumbinary material by the ejecta from nova outburst. The photometric and spectroscopic data show that the system reached quiescence in 2009, which means that for the first time all of the phases of a nova outburst were observed in an extragalactic symbiotic star. The data indicate that most probably there were three outbursts observed in LMC S154, which would make this system a member of a rare class of symbiotic recurrent novae. The recurrent nature of the system is supported by the discovery of coronal lines in the spectra, which are observed only in symbiotic stars with massive white dwarfs and with short-recurrence-time outbursts. Gathered evidence is sufficient to classify LMC S154 as the first bona fide extragalactic symbiotic nova, which is likely a recurrent nova. It is also the first nova with a carbon-rich donor.
Abundances of disk and bulge giants from high-resolution optical spectra
Authors: Lomaeva M. , Jönsson H. , Ryde N. , Schultheis M. , Thorsbro B.
Published: March 2019

Context. The formation and evolution of the Galactic bulge and the Milky Way is still a debated subject. Observations of the X-shaped bulge, cylindrical stellar motions, and the presumed existence of a fraction of young stars in the bulge have suggested that it formed through secular evolution of the disk and not through gas dissipation and/or mergers, as thought previously.

Aims. Our goal was to measure the abundances of six iron-peak elements (Sc, V, Cr, Mn, Co, and Ni) in the local thin and thick disks and in the bulge. These abundances can provide additional observational constraints for Galaxy formation and chemical evolution models, and help us to understand whether the bulge has emerged from the thick disk or not.

Methods. We use high-resolution optical spectra of 291 K giants in the local disk mostly obtained by the FIES at NOT (signal-to-noise ratio (S/N) of 80–100) and 45 K giants in the bulge obtained by the UVES/FLAMES at VLT (S/N of 10–80). The abundances are measured using Spectroscopy Made Easy (SME). Additionally, we apply non-local thermodynamic equilibrium corrections to the ratios [Mn/Fe] and [Co/Fe]. The thin and thick disks were separated according to their metallicity, [Ti/Fe], as well as proper motions and the radial velocities from Gaia DR2.

Results. The trend of [V/Fe] vs. [Fe/H] shows a separation between the disk components, being more enhanced in the thick disk. Similarly, the [Co/Fe] vs. [Fe/H] trend shows a hint of an enhancement in the local thick disk. The trends of V and Co in the bulge appear to be even more enhanced, although within the uncertainties. The decreasing value of [Sc/Fe] with increasing metallicity is observed in all the components, while our [Mn/Fe] value steadily increases with increasing metallicity in the local disk and the bulge instead. For Cr and Ni we find a flat trend following iron for the whole metallicity range in the disk and the bulge. The ratio of [Ni/Fe] appears slightly overabundant in the thick disk and the bulge compared to the thin disk, although the difference is minor.

Conclusions. The somewhat enhanced ratios of [V/Fe] and [Co/Fe] observed in the bulge suggest that the local thick disk and the bulge might have experienced different chemical enrichment and evolutionary paths. However, we are unable to predict the exact evolutionary path of the bulge solely based on these observations. Galactic chemical evolution models could, on the other hand, allow us to predict them using these results.
Gaia DR2 unravels incompleteness of nearby cluster population: new open clusters in the direction of Perseus
Authors: Cantat-Gaudin T. , Krone-Martins A. , Sedaghat N. , Farahi A. , de Souza R. S. , Skalidis R. , Malz A. I. , Macêdo S. , Moews B. , Jordi C. , Moitinho A. , Castro-Ginard A. , Ishida E. E. O. , Heneka C. , Boucaud A. , Trindade A. M. M.
Published: March 2019

Context. Open clusters (OCs) are popular tracers of the structure and evolutionary history of the Galactic disc. The OC population is often considered to be complete within 1.8 kpc of the Sun. The recent Gaia Data Release 2 (DR2) allows the latter claim to be challenged.

Aims. We perform a systematic search for new OCs in the direction of Perseus using precise and accurate astrometry from Gaia DR2.

Methods. We implemented a coarse-to-fine search method. First, we exploited spatial proximity using a fast density-aware partitioning of the sky via a k-d tree in the spatial domain of Galactic coordinates, (l, b). Secondly, we employed a Gaussian mixture model in the proper motion space to tag fields quickly around OC candidates. Thirdly, we applied an unsupervised membership assignment method, UPMASK, to scrutinise the candidates. We visually inspected colour-magnitude diagrams to validate the detected objects. Finally, we performed a diagnostic to quantify the significance of each identified over-density in proper motion and in parallax space.

Results. We report the discovery of 41 new stellar clusters. This represents an increment of at least 20% of the previously known OC population in this volume of the Milky Way. We also report on the clear identification of NGC 886, an object previously considered an asterism. This study challenges the previous claim of a near-complete sample of OCs up to 1.8 kpc. Our results reveal that this claim requires revision, and a complete census of nearby OCs is yet to be found.
Towards open and reproducible multi-instrument analysis in gamma-ray astronomy
Authors: Nigro C. , Deil C. , Zanin R. , Hassan T. , King J. , Ruiz J. E. , Saha L. , Terrier R. , Brügge K. , Nöthe M. , Bird R. , Lin T. T. Y. , Aleksić J. , Boisson C. , Contreras J. L. , Donath A. , Jouvin L. , Kelley-Hoskins N. , Khelifi B. , Kosack K. , Rico J. , Sinha A.
Published: March 2019

The analysis and combination of data from different gamma-ray instruments involves the use of collaboration proprietary software and case-by-case methods. The effort of defining a common data format for high-level data, namely event lists and instrument response functions (IRFs), has recently started for very-high-energy gamma-ray instruments, driven by the upcoming Cherenkov Telescope Array (CTA). In this work we implemented this prototypical data format for a small set of MAGIC, VERITAS, FACT, and H.E.S.S. Crab nebula observations, and we analyzed them with the open-source gammapy software package. By combining data from Fermi-LAT, and from four of the currently operating imaging atmospheric Cherenkov telescopes, we produced a joint maximum likelihood fit of the Crab nebula spectrum. Aspects of the statistical errors and the evaluation of systematic uncertainty are also commented upon, along with the release format of spectral measurements. The results presented in this work are obtained using open-access on-line assets that allow for a long-term reproducibility of the results.
Pluto’s ephemeris from ground-based stellar occultations (1988–2016)
Authors: Desmars J. , Meza E. , Sicardy B. , Assafin M. , Camargo J. I. B. , Braga-Ribas F. , Benedetti-Rossi G. , Dias-Oliveira A. , Morgado B. , Gomes-Júnior A. R. , Vieira-Martins R. , Behrend R. , Ortiz J. L. , Duffard R. , Morales N. , Santos Sanz P.
Published: March 2019

Context. From 1988 to 2016, several stellar occultations have been observed to characterise Pluto’s atmosphere and its evolution. From each stellar occultation, an accurate astrometric position of Pluto at the observation epoch is derived. These positions mainly depend on the position of the occulted star and the precision of the timing.

Aims. We present 19 Pluto’s astrometric positions derived from occultations from 1988 to 2016. Using Gaia DR2 for the positions of the occulted stars, the accuracy of these positions is estimated at 2−10 mas, depending on the observation circumstances. From these astrometric positions, we derive an updated ephemeris of Pluto’s system barycentre using the NIMA code.

Methods. The astrometric positions were derived by fitting the light curves of the occultation by a model of Pluto’s atmosphere. The fits provide the observed position of the centre for a reference star position. In most cases other publications provided the circumstances of the occultation such as the coordinates of the stations, timing, and impact parameter, i.e. the closest distance between the station and centre of the shadow. From these parameters, we used a procedure based on the Bessel method to derive an astrometric position.

Results. We derive accurate Pluto’s astrometric positions from 1988 to 2016. These positions are used to refine the orbit of Pluto’system barycentre providing an ephemeris, accurate to the milliarcsecond level, over the period 2000−2020, allowing for better predictions for future stellar occultations.
Long-term monitoring of the outgassing and composition of comet 67P/Churyumov-Gerasimenko with the Rosetta/MIRO instrument
Authors: Biver N. , Bockelée-Morvan D. , Hofstadter M. , Lellouch E. , Choukroun M. , Gulkis S. , Crovisier J. , Schloerb F. P. , Rezac L. , von Allmen P. , Lee S. , Leyrat C. , Ip W. H. , Hartogh P. , Encrenaz P. , Beaudin G. ,   the MIRO team
Published: March 2019

We present the analysis of ≈100 molecular maps of the coma of comet 67P/Churyumov-Gerasimenko that were obtained with the MIRO submillimeter radiotelescope on board the Rosetta spacecraft. From the spectral line mapping of H216O, H218O, H217O, CH3OH, NH3, and CO and some fixed nadir pointings, we retrieved the outgassing pattern and total production rates for these species. The analysis covers the period from July 2014, inbound to perihelion, to June 2016, outbound, and heliocentric distancesrh= 1.24–3.65 AU. A steep evolution of the outgassing rates with heliocentric distance is observed, typically inrh−16, with significant differences between molecules (e.g. steeper variation for H2O post-perihelion than for methanol). As a consequence, the abundances relative to water in the coma vary. The CH3OH and CO abundances increase after perihelion, while the NH3abundance peaks around perihelion and then decreases. Outgassing patterns have been modeled as 2D Gaussian jets. The width of these jets is maximum around the equinoxes when the bulk of the outgassing is located near the equator. From July 2014 to February 2015, the outgassing is mostly restricted to a narrower jet (full width at half-maximum ≈80°) originating from high northern latitudes, while around perihelion, most of the gaseous production comes from the southernmost regions ( − 80 ± 5° cometocentric latitude) and forms a 100°–130° (full width at half-maximum) wide fan. We find a peak production of water of 0.8 × 1028molec. s−1, 2.5 times lower than measured by the ROSINA experiment, and place an upper limit to a 50% additional production that could come from the sublimation of icy grains. We estimate the total loss of ices during this perihelion passage to be 4.18 ± 0.18 × 109kg. We derive a dust-to-gas ratio in the lost material of 0.7–2.3 (including all sources of errors) based on the nucleus mass loss of 10.5 ± 3.4 × 109kg estimated by the RSI experiment. We also obtain an estimate of the H218O/H217O ratio of 5.6 ± 0.8.
Extended stellar systems in the solar neighborhood
Authors: Fürnkranz Verena , Meingast Stefan , Alves João
Published: March 2019

We report the discovery of a kinematically cold group of stars, located in the immediate neighborhood of the well-known star cluster Coma Berenices (Mel 111). The new group identified in tangential velocity space as measured by Gaia contains at least 177 coeval members distributed in two subgroups, and appears as a flattened structure parallel to the plane, stretching for about 50 pc. More remarkably, the new group, which appears to have formed about 300 Myr later than Mel 111 in a different part of the Galaxy, will share essentially the same volume with the older cluster when the centers of both groups will be at their closest in 13 Myr. This will result in the mixing of two unrelated populations with different metallicities. The phase of cohabitation for these two groups is about 20–30 Myr, after which the two populations will drift apart. We estimate that temporal cohabitation of such populations is not a rare event in the disk of the Milky Way, and of the order of once per Galactic revolution. Our study also unveils the tidal tails of the Mel 111 cluster.
Comparative analysis of microRNA profiles between wild and cultured Haemaphysalis longicornis (Acari, Ixodidae) ticks
Authors: Luo Jin , Ren Qiaoyun , Chen Ze , Liu Wenge , Qu Zhiqiang , Xiao Ronghai , Chen Ronggui , Lin Hanliang , Wu Zegong , Luo Jianxun , Yin Hong , Wang Hui , Liu Guangyuan
Published: March 2019

The miRNA profiles of a Haemaphysalis longicornis wild-type (HLWS) and of a Haemaphysalis longicornis cultured population (HLCS) were sequenced using the Illumina Hiseq 4000 platform combined with bioinformatics analysis and real-time polymerase chain reaction (RT-PCR). A total of 15.63 and 15.48 million raw reads were acquired for HLWS and HLCS, respectively. The data identified 1517 and 1327 known conserved miRNAs, respectively, of which 342 were differentially expressed between the two libraries. Thirty-six novel candidate miRNAs were predicted. To explain the functions of these novel miRNAs, Gene Ontology (GO) analysis was performed. Target gene function prediction identified a significant set of genes related to salivary gland development, pathogen-host interaction and regulation of the defence response to pathogens expressed by wild H. longicornis ticks. Cellular component biogenesis, the immune system process, and responses to stimuli were represented at high percentages in the two tick libraries. GO enrichment analysis showed that the percentages of most predicted functions of the target genes of miRNA were similar, as were certain specific categories of functional enhancements, and that these genes had different numbers and specific functions (e.g., auxiliary transport protein and electron carrier functions). This study provides novel findings showing that miRNA regulation affects the expression of immune genes, indicating a considerable influence of environment-induced stressful stimulation on immune homeostasis. Differences in the living environments of ticks can lead to differences in miRNAs between ticks and provide a basis and a convenient means to screen for genes encoding immune factors in ticks.
Quelles spécificités pour les soudures dans le nucléaire ?
Authors: Carlier Louis , Leclerc Stéphane
Published: March 2019

En matière de sûreté nucléaire, la qualité des soudures est primordiale. Les nouvelles technologies utilisées ces dernières années ont augmenté le degré d’exigence dans ce domaine. Qu’est-ce qui différencie la notion de qualité d’une soudure « classique » de celle de l’industrie nucléaire ?
Cardiac Biomarkers: What Is and What Can Be
Authors: Jacob Rachel , Khan Mahmood
Published: March 2019

Cardiac biomarkers are of great importance in the timely, accurate diagnosis and management of acute coronary syndrome as well as the prognosis. Diagnosis in the golden period is of utmost importance to institute therapy at the earliest and possibly reverse the myocardial damage. Cardiac biomarkers are also a powerful tool for triaging. Among the many biomarkers, the earliest examined were the myocardial enzymes, several myocardial proteins, peptides, and many other molecules. The latest addition to the repertoire is the microRNAs, which are stable molecules detectable in circulation. About four groups are found to be involved in regulation of circulatory system, and some show promise as specific and early markers of acute coronary syndrome and cardiac dysfunction. As in other fields of medicine, personalized precise treatment may be possible with the use of microRNAs. However, as of now, a multipronged approach, involving different markers of which troponins are necessary, seems to be the best way forward.
Safeuristics! Do Heuristic Evaluation Violation Severity Ratings Correlate with Patient Safety Severity Ratings for a Native Electronic Health Record Mobile Application?
Authors: Kennedy Brandan , Kerns Ellen , Chan Y. , Chaparro Barbara , Fouquet Sarah
Published: March 2019

Objective Usability of electronic health records (EHRs) remains challenging, and poor EHR design has patient safety implications. Heuristic evaluation detects usability issues that can be classified by severity. The National Institute of Standards and Technology provides a safety scale for EHR usability. Our objectives were to investigate the relationship between heuristic severity ratings and safety scale ratings in an effort to analyze EHR safety.

Materials and Methods Heuristic evaluation was conducted on seven common mobile EHR tasks, revealing 58 heuristic violations and 28 unique usability issues. Each usability issue was independently scored for severity by trained hospitalists and a Human Factors researcher and for safety severity by two physician informaticists and two clinical safety professionals.

Results Results demonstrated a positive correlation between heuristic severity and safety severity ratings. Regression analysis demonstrated that 49% of safety risk variability by clinical safety professionals (r = 0.70; n = 28) and 42% of safety risk variability by clinical informatics specialists (r = 0.65; n = 28) was explained by usability severity scoring of problems outlined by heuristic evaluation. Higher severity ratings of the usability issues were associated with increased perceptions of patient safety risk.

Discussion This study demonstrated the use of heuristic evaluation as a technique to quickly identify usability problems in an EHR that could lead to safety issues. Detection of higher severity ratings could help prioritize failures in EHR design that more urgently require design changes. This approach is a cost-effective technique for improving usability while impacting patient safety.

Conclusion Results from this study demonstrate the efficacy of the heuristic evaluation technique to identify usability problems that impact safety of the EHR. Also, the use of interdisciplinary teams for evaluation should be considered for severity assessment.
Feasibility Investigation of Ipsilateral Reoperations by Thoracoscopy for Major Lung Resection
Authors: Sun Weiyan , Zhang Lei , Li Zeyao , Chen Donglai , Jiang Gening , Hu Jian , Chen Chang
Published: March 2019

Background Video-assisted thoracoscopic surgery (VATS) has become the preferred approach for minimizing harm from thoracic operations. There is no report, however, which has discussed the feasibility of VATS in ipsilateral reoperation of major lung resection.

Methods The present study included patients who had undergone ipsilateral reoperation of major lung resection by VATS from October 2009 to May 2017. Referring clinical data were recruited for analysis.

Results Fourteen patients were recruited in the present study, including nine patients who underwent lobectomy and five who underwent segmentectomy during the second operation. Different hila were found in 6 patients, and pleural adhesions appeared in 10 patients. The average intraoperative blood loss was 203.6 ± 121.7 mL, and the mean operating room time was 2.2 ± 0.5 hours. There were no intraoperative deaths, and only one patient required conversion to thoracotomy. The average drainage time was 5.9 ± 4.6, and the mean hospital stay was 6.7 ± 4.2 days.

Conclusion Though it is technically demanding to safely handle the changed hilum structure caused by the last operation, major lung resection by VATS is feasible for ipsilateral reoperation in appropriate candidates.
Lateral Radial Head Subluxation as a Complication Following Proximal Ulnar Osteotomy or Ostectomy in Eight Dogs
Authors: Williams Heather , Arthurs Gareth , Burton Neil , Kulendra Elvin , Radke Heidi , Parsons Kevin
Published: March 2019

Objectives The aim of this study was to report the complication of lateral radial head subluxation following proximal ulnar osteotomy (PUOO) or proximal ulnar ostectomy (PUOE) in eight dogs.

Materials and Methods Case records and diagnostic imaging of dogs developing lateral radial head subluxation following PUOO (n = 7) or PUOE (n = 2) were retrospectively reviewed. Information pertaining to clinical history, signalment, presenting condition, lameness grade, diagnostic imaging and initial surgery details, postoperative complications and their management were retrieved. Outcomes were established from subsequent clinical histories or telephone interviews with referring veterinarians. Comparison was made to a single-centre cohort without lateral radial head subluxation following PUOO or PUOE.

Results Eight dogs (median age: 9.5 months [range: 6 months–6 years], median weight 7.7 kg [range: 5–28 kg]) were included. Six dogs had a PUOO performed; five dogs had unilateral surgery and one had bilateral surgery. Two dogs had unilateral PUOE surgery. Median time to diagnosis of lateral radial head subluxation following surgery was 6.5 weeks (range: 2–20 weeks). Five of the eight dogs had surgical revision of lateral radial head subluxation. Resolution of lateral radial head subluxation was achieved in four dogs, with three achieving acceptable to good mobility. One dog had poor postoperative mobility. A fifth dog remained lame after revision surgery failure. Three dogs did not have revision surgery; two underwent limb amputation and one dog remained lame as revision surgery was declined.

Clinical Significance Lateral radial head subluxation is a potentially severe postoperative complication following PUOO or PUOE.
Age-Related Variances in Patients with Tibial Plateau Fractures
Authors: Oladeji Lasun O. , Worley John R. , Crist Brett D.
Published: March 2019

Tibial plateau fractures account for approximately 8% of fractures in the elderly population. Treatment strategies in the elderly are similar to those for younger patients; however, practitioners must account for the elevated comorbidity burden in this population. To date, few studies have analyzed age-based outcomes in patients with tibial plateau fractures. Therefore, the purpose of this study was to determine age-related variances in demographics, fracture characteristics, mechanism of injury, and complications. A 10-year retrospective review was conducted to identify patients who received treatment for a tibial plateau fracture. There were 351 patients (360 tibial plateau fractures) who were identified and subsequently stratified according to their age at the time of injury. Patients were classified as elderly if they were 65 years of age or older at the time of injury; all other patients were included in the control cohort. These two cohorts were analyzed using bivariate analysis to isolate for age-related variations with respect to risk factors, mechanism of injury, and complications. There were 351 patients (360 tibial plateau fractures) with a median follow-up of 1.84 ± 2.44 years who met inclusion criteria. There were a greater proportion of women in the elderly cohort as compared with the younger cohort (60.0 vs. 43.4%, p = 0.06). Elderly patients were significantly more likely to present with diabetes (33.3 vs. 16.1%, p = 0.01) or osteoporosis (14.3 vs. 1.6%, p = 0.001). Younger patients were significantly more likely to require further surgery to address ligament (12.6 vs. 0%, p = 0.008), meniscus (20.9 vs. 7.1%, p = 0.036), or cartilage pathology (13.6 vs. 0%, p = 0.005). There was no difference in the arthroplasty conversion rate (4.8% elderly vs. 7.9% control, p = 0.755). While elderly patients presented with a greater comorbidity burden, they had equivalent or better short-term outcomes when compared with their younger peers when treated with open reduction and internal fixation (ORIF). Despite the recent interest in primary total knee arthroplasty for elderly patients with tibial plateau fractures, the results of this study suggest that elderly patients may respond well when treated with ORIF following a tibial plateau fracture.
Posterior Reversible Encephalopathy Syndrome in an Adolescent with Acute Poststreptococcal Glomerulonephritis
Authors: Doğan Çağla Serpil , Aksoy Gülşah Kaya , Kutluk Muhammed Gültekin , Özkan Mehmet Burak
Published: March 2019

Posterior reversible encephalopathy syndrome (PRES) is a rare but severe complication of acute poststreptococcal glomerulonephritis (APSGN) in children. A 13-year old boy was diagnosed with APSGN based on clinical, laboratory, and renal biopsy findings. On the third hospital day, his blood pressure (BP) was 130/80 mm Hg on antihypertensive and diuretic treatment. He then developed confusion, blurry vision, and changes in speech and behavior. Over the next few hours, his BP increased to 160/90 to 170/90 mm Hg (99th percentile, 135/90 mm Hg). Magnetic resonance imaging of the brain revealed prominent hyperintensities in the right temporal, right temporo-occipital, and right parieto-occipital gray, and white matter on T2-weighted and fluid-attenuated inversion recovery images, compatible with PRES (posterior reversible encephalopathy syndrome). Electroencephalography showed generalized epileptiform activity. After treatment with anticonvulsant and additional antihypertensive medications, his clinical symptoms and neuroimaging findings were resolved. Posterior reversible encephalopathy syndrome should be considered in the differential diagnosis of patients with APSGN developing sudden neurological symptoms without severe increases in BP.
Label-free biosensing using a microring resonator integrated with poly-(dimethylsiloxane) microfluidic channels
Authors: Wu Shangquan , Guo Yingying , Wang Wanjun , Zhou Jie , Zhang Qingchuan
Published: March 2019

Microring resonators have shown promising potential for highly sensitive, label-free, real-time detection of biomolecules. Accurate quantitative detection of target molecules through use of photonic integrated circuits has been demonstrated for environmental monitoring and medical diagnostics. Here, we described the design, fabrication, and characterization of a highly sensitive, label-free microring optical resonator integrated with poly-(dimethylsiloxane) microfluidic channels, which consumes only 30 µl of sample solution. The resonance wavelength shifts resulting from the change in the effective refraction index can be measured in situ, and thus the binding events on the resonator surface, including antibody immobilization, blocking of the resonator surface, and the specific binding of antibody and antigen, can be recorded throughout the entire experimental process in real time. We measured the binding events for the detection of human immunoglobulin G. The system had a detection limit of 0.5 µg/ml, a value substantially (14 times) lower than that of a previously reported microring resonator. To verify the usefulness and adaptability of this technique, human epidermal growth factor receptor 2 was used for the detection. The microring optical resonator was able to monitor reactions between biological molecules in real time and thus can be used in quantitative detection and biological sensing with little sample consumption.
Flexible, strain gated logic transducer arrays enabled by initializing surface instability on elastic bilayers
Authors: Wang Cong , Xu Ben Bin , Terry Jonathan G. , Smith Stewart , Walton Anthony J. , Wang Steven , Lv Haibao , Li Yifan
Published: March 2019

Developing flexible sensors with a high strain sensing range could enable widespread downstream applications, by allowing intimate, mechanically conformable integration with soft biological tissues. By characterizing interconnected metal electrode arrays on super-flexible substrates, we have established a surface deformation control strategy of an array of strain transducers. The strain gated switches are capable of measuring various compressive strains (up to 60%) by bringing metal electrodes into self-contact via creasing elastic instability beyond a threshold substrate strain. The designed devices have been developed to explore the geometry design effect on the electrode-elastomer “stiff film on soft elastomer” surface deformation. The enabled transducer array yielded a stepwise strain-electrical resistance switching mechanism which opens up the potential of future interconnected sensor array type of super-compressible devices.
Interplay between random fluctuations and rate dependent phenomena at slow passage to limit-cycle oscillations in a bistable thermoacoustic system
Authors: Unni Vishnu R. , Gopalakrishnan E. A. , Syamkumar K. S. , Sujith R. I. , Surovyatkina Elena , Kurths Jürgen
Published: March 2019

We study the impact of noise on the rate dependent transitions in a noisy bistable oscillator using a thermoacoustic system as an example. As the parameter—the heater power—is increased in a quasi-steady manner, beyond a critical value, the thermoacoustic system undergoes a subcritical Hopf bifurcation and exhibits periodic oscillations. We observe that the transition to this oscillatory state is often delayed when the control parameter is varied as a function of time. However, the presence of inherent noise in the system introduces high variability in the characteristics of this critical transition. As a result, if the value of the system variable—the acoustic pressure—approaches the noise floor before the system crosses the unstable manifold, the effect of rate on the critical transition becomes irrelevant in determining the transition characteristics, and the system undergoes a noise-induced tipping to limit-cycle oscillations. The presence of noise-induced tipping makes it difficult to identify the stability regimes in such systems by using stability maps for the corresponding deterministic system.
Accuracy of tip-sample interaction measurements using dynamic atomic force microscopy techniques: Dependence on oscillation amplitude, interaction strength, and tip-sample distance
Authors: Dagdeviren Omur E. , Schwarz Udo D.
Published: March 2019

Atomic force microscopy (AFM) is a versatile surface characterization method that can map a sample’s topography with high spatial resolution while simultaneously interrogating its surface chemistry through the site-specific high-resolution quantification of the forces acting between the sample and the probe tip. Thanks to considerable advances in AFM measurement technology, such local measurements of chemical properties have gained much popularity in recent years. To this end, dynamic AFM methodologies are implemented where either the oscillation frequency or the oscillation amplitude and phase of the vibrating cantilever are recorded as a function of tip-sample distance and subsequently converted to reflect tip-sample forces or interaction potentials. Such conversion has, however, been shown to produce non-negligible errors when applying the most commonly used mathematical conversion procedures if oscillation amplitudes are of the order of the decay length of the interaction. Extending on these earlier findings, the computational study presented in this paper reveals that the degree of divergence from actual values may also critically depend on both the overall strength of tip-sample interaction and the distance at which the interaction is obtained. These systematic errors can, however, be effectively eliminated by using oscillation amplitudes that are sufficiently larger than the decay length of the interaction potential.
Forced synchronization of a multilayer heterogeneous network of chaotic maps in the chimera state mode
Authors: Rybalova E. V. , Vadivasova T. E. , Strelkova G. I. , Anishchenko V. S. , Zakharova A. S.
Published: March 2019

We study numerically forced synchronization of a heterogeneous multilayer network in the regime of a complex spatiotemporal pattern. Retranslating the master chimera structure in a driving layer along subsequent layers is considered, and the peculiarities of forced synchronization are studied depending on the nature and degree of heterogeneity of the network, as well as on the degree of asymmetry of the inter-layer coupling. We also analyze the possibility of synchronizing all the network layers with a given accuracy when the coupling parameters are varied.
Synthesis of Liquid Polyisoprene with High cis-1,4 Unit Content and Narrow Molecular Weight Distribution Using Neodymium Phosphate Catalyst
Authors: Liu Jie , Min Xin , Zhu Xiuzhong , Wang Zichao , Wang Tong , Fan Xiaodong
Published: March 2019

The polymerization of isoprene (Ip) initiated by a ternary catalytic system consisting of liquid Nd(P204)3 (Nd), Al(i-Bu)2H (Al), and CHCl3 (Cl) in cyclohexane was examined. The effects of order of addition and amount of Ip, Al, and Cl in the catalyst on the polymerization were evaluated. The molecular weight (Mn), molecular weight distribution (Mw/Mn), and microstructure of the polymer were characterized using size exclusion chromatography and multiangle light scattering, FT-IR, 1H NMR and 13C NMR analysis. The results indicate that the order of addition, i.e. Nd+Ip+Al+Cl and ratios of [Ip]/[Nd]=30, [Al]/[Nd]=20, and [Cl]/[Nd]=3 were essential for the optimized ternary catalyst system Nd(P204)3/Al(i-Bu)2H/CHCl3. The resulting liquid polyisoprene (LIR) has a high cis-1,4 unit content (>98%) and a narrow molecular weight distribution (Mw/Mn<1.2). The molecular weight of the polymer was precisely controlled.
Quantity and biodegradability of dissolved organic matter released from sequentially leached soils, as influenced by the extent of soil drying prior to rewetting
Authors: Vujinović Tihana , Clough Timothy J. , Curtin Denis , Meenken Esther D. , Lehto Niklas J. , Beare Michael H.
Published: March 2019

Soil rewetting can induce a flush of organic matter mineralisation, but the factors underpinning this mineralisation response are poorly understood. We investigated the effects of antecedent soil water content, before rewetting, on the quantity, quality and biodegradability of dissolved organic matter present in the leachate pore volumes from a soil under two different management histories: arable and grassland. Soils were collected at field capacity (FC) and dried to give four soil gravimetric water contents (θg): 22% (not dried, left at FC), 15%, 8% and <2% (air dry, AD). Soils were repacked to the same bulk density (1.1 g cm–3) and each core was sequentially leached, with four pore volumes collected. The total amount of dissolved organic carbon (DOC) leached increased (P < 0.001) only in the soils that had been air-dried before rewetting (3.8 and 5.3 mg g–1 soil C, for arable and grassland respectively), while among the other θg treatments differences were relatively small (1.6–2.4 mg g–1 soil C). The pre-rewetting θg treatment affected the DOC content of the pore volume leached (P < 0.001): in the grassland soil, the DOC of the AD treatment was consistently twice as high as the other θg treatments, but this trend was not as consistent in the arable soil. For all θg treatments and both soils, specific ultraviolet absorbance at 254 nm increased as leaching progressed. Biodegradability, expressed as cumulative CO2 produced per unit of DOC in leachates, was significantly lower in the first pore volume of all treatments in the grassland soil and increased with sequential leaching. In the arable soil, differences were small or insignificant across the pore volumes leached, but were large and inconsistent across the θg treatments. These findings improve our understanding of how antecedent soil water content affects the quantity and quality of dissolved organic matter released when soils are rewetted, and the potential for soil carbon losses.