bluuebunny/crossref_metadata_2025 huggingface dataset:
Diminishing high‐frequency directivity due to a source effect: Empirical evidence from small earthquakes in the Abruzzo region, Italy
Authors: Pacor F. , Gallovič F. , Puglia R. , Luzi L. , D'Amico M.
Published: May 2016

The aim of this study is to investigate the directivity effects of ~250 aftershocks (magnitudes 3–5.5) of the Mw 6.1 2009 L'Aquila earthquake (central Italy). To this end, we estimate the apparent source spectra at each station removing path and site effects inferred by standard Generalized Inversion Technique. Then, we evaluate the residuals between the apparent source spectra and the event mean source spectrum at selected frequencies. We investigate azimuthal and frequency dependence of the residuals for 40 events with the best station coverage. For most of events with the strongest directivity effect (Mw 3.4–4.0), we observe a remarkable decrease of the directivity amplification at high frequencies, which has not yet been documented for such relatively small‐magnitude events. Since there is negligible distance dependence, we ascribe this observation to a source phenomenon such as significant small‐scale rupture propagation complexity.
Magnetospheric Multiscale observations of large‐amplitude, parallel, electrostatic waves associated with magnetic reconnection at the magnetopause
Authors: Ergun R. E. , Holmes J. C. , Goodrich K. A. , Wilder F. D. , Stawarz J. E , Eriksson S. , Newman D. L. , Schwartz S. J. , Goldman M. V. , Sturner A. P. , Malaspina D. M. , Usanova M. E. , Torbert R. B. , Argall M. , Lindqvist P.‐A. , Khotyaintsev Y. , Burch J. L. , Strangeway R. J. , Russell C. T. , Pollock C. J. , Giles B. L. , Dorelli J. J. C. , Avanov L. , Hesse M. , Chen L. J. , Lavraud B. , Le Contel O. , Retino A. , Phan T. D. , Eastwood J. P. , Oieroset M. , Drake J. , Shay M. A. , Cassak P. A. , Nakamura R. , Zhou M. , Ashour‐Abdalla M. , André M.
Published: May 2016

We report observations from the Magnetospheric Multiscale satellites of large‐amplitude, parallel, electrostatic waves associated with magnetic reconnection at the Earth's magnetopause. The observed waves have parallel electric fields (E||) with amplitudes on the order of 100 mV/m and display nonlinear characteristics that suggest a possible net E||. These waves are observed within the ion diffusion region and adjacent to (within several electron skin depths) the electron diffusion region. They are in or near the magnetosphere side current layer. Simulation results support that the strong electrostatic linear and nonlinear wave activities appear to be driven by a two stream instability, which is a consequence of mixing cold (<10 eV) plasma in the magnetosphere with warm (~100 eV) plasma from the magnetosheath on a freshly reconnected magnetic field line. The frequent observation of these waves suggests that cold plasma is often present near the magnetopause.
Observation of high‐frequency electrostatic waves in the vicinity of the reconnection ion diffusion region by the spacecraft of the Magnetospheric Multiscale (MMS) mission
Authors: Zhou M. , Ashour‐Abdalla M. , Berchem J. , Walker R. J. , Liang H. , El‐Alaoui M. , Goldstein M. L. , Lindqvist P.‐A. , Marklund G. , Khotyaintsev Y. V. , Ergun R. E. , Wilder F. D. , Russell C. T. , Strangeway R. J. , Zhao C. , Paterson W. R. , Giles B. L. , Pollock C. J. , Torbert R. B. , Burch J. L. , Dorelli J. C. , Gershman D. J. , Avanov L. A. , Lavraud B. , Chandler M. O.
Published: May 2016

We report Magnetospheric Multiscale observations of high‐frequency electrostatic waves in the vicinity of the reconnection ion diffusion region on the dayside magnetopause. The ion diffusion region is identified during two magnetopause crossings by the Hall electromagnetic fields, the slippage of ions with respect to the magnetic field, and magnetic energy dissipation. In addition to electron beam modes that have been previously detected at the separatrix on the magnetospheric side of the magnetopause, we report, for the first time, the existence of electron cyclotron harmonic waves at the magnetosheath separatrix. Broadband waves between the electron cyclotron and electron plasma frequencies, which were probably generated by electron beams, were found within the magnetopause current sheet. Contributions by these high‐frequency waves to the magnetic energy dissipation were negligible in the diffusion regions as compared to those of lower‐frequency waves.
Validation of the laboratory measurements at seismic frequencies using the Kramers‐Kronig relationship
Authors: Mikhaltsevitch Vassily , Lebedev Maxim , Gurevich Boris
Published: May 2016

We present a simple procedure concerning the application of the Kramers‐Kronig relation for the validation of the laboratory measurements of the extensional attenuation and Young's modulus carried out on the solid specimens at seismic frequencies. The local approximation of the Kramers‐Kronig relationship was applied to verify the seismic‐frequency measurements conducted on four specimens: a viscoelastic polymethyl‐methacrylate (PMMA) sample, and two water‐ and one glycerol‐saturated sandstone samples. The experimental tests were performed at various axial (PMMA sample) and confining (sandstone samples) pressures. The measurements conducted on the PMMA sample and saturated sandstones revealed prominent extensional attenuation and significant dispersion of the Young's modulus. Our analysis shows that the quantitative relationship between the extensional attenuation and the Young's modulus is consistent with the causality principle presented by the Kramers‐Kronig relationship. No particular physical models implying any constraints on the physical properties of the samples are required for this validation.
Tropical cyclone effects on the equatorial ionosphere: First result from the Indian sector
Authors: Guha Anirban , Paul Bapan , Chakraborty Monti , De Barin Kumar
Published: May 2016

Ionospheric response to the effects of tropical cyclone (TC) “Mahasen” in 2013 and Hudhud in 2014 is studied on the equatorial ionosphere over the Indian sector for the first time using Global Positioning System‐derived total electron content (TEC) data. We observed an anomalous decrease of 3.8 TEC unit (1 TECU = 1016 el m−2) in vertical TEC (VTEC) value from the monthly mean for TC Mahasen and 2.1 TECU for TC Hudhud on the day of the landfall. We have also observed similar VTEC depletion of 1.5, 1.9, and 2.1 TECU for three different receivers on the landfall day for TC Vongfong over Japan. This anomalous decrease is observed over a wide zone around the trajectory of the cyclone during the active cyclonic storm stage. This observed anomaly might be the result of combined effect of TC‐inspired gravity waves, ejection of neutral particles from the terminator of a TC, and lightning electric fields which redistribute the chemical constituents of the ionosphere by increasing the number of neutral particles at different ionospheric heights, thus decreasing the TEC over the satellite‐receiver path.
Sensitivity of earthquake source inversions to atmospheric noise and corrections of InSAR data
Authors: Scott Chelsea Phipps , Lohman Rowena Benfer
Published: May 2016

Tropospheric phase delays pose a major challenge to InSAR (interferometric synthetic aperture radar)‐based studies of tectonic deformation. One approach to the mitigation of effects from tropospheric noise is the application of elevation‐dependent corrections based on empirical fits between elevation and interferometric phase. We quantify the effects of corrections with a range of complexity on inferred earthquake source parameters using synthetic interferograms with known atmospheric characteristics. We infer statistical properties of the stratified component of the atmosphere using pressure, temperature, and water vapor data from the North America Regional Reanalysis model over our region of interest in the Basin and Range province of the western United States. The statistics of the simulated atmospheric turbulence are estimated from InSAR and Global Positioning System data. We demonstrate potentially significant improvements in the precision of earthquake magnitude, depth, and dip estimates for several synthetic earthquake focal mechanisms following a correction for spatially variable atmospheric characteristics, relative to cases where the correction is based on a uniform delay versus elevation relationship or where no correction is applied. We apply our approach to the 1992 M5.6 Little Skull Mountain, Nevada, earthquake and demonstrate that the earthquake source parameter error bounds decrease in size after applying the atmospheric corrections. Our approach for evaluating the impact of atmospheric noise on inferred fault parameters is easily adaptable to other regions and source mechanisms.
Optical Coherence
Authors: Visser Taco D.
Published: May 2016

The coherence properties of an optical source determine how the emitted field propagates, scatters, and behaves on focusing. Because the state of coherence can be actively controlled, this provides an additional tool for field shaping. We show that the observation that two sources with an identical spectrum can produce fields whose spectra are different can be explained by realizing that this field property is in fact a secondary quantity. The primary or fundamental property from which the spectrum is derived is the coherence function of the source. The propagation of this function is governed by wave equations. By calculating the propagated correlation function, the local spectrum can be determined. We illustrate how the manipulation of spatial coherence can give rise to novel physical effects in focusing and scattering.
Genetic counseling and testing for Huntington's disease: A historical review
Authors: Nance Martha A.
Published: May 2016

This manuscript describes the ways in which genetic counseling has evolved since John Pearson and Sheldon Reed first promoted “a genetic education” in the 1950s as a voluntary, non‐directive clinical tool for permitting individual decision making. It reviews how the emergence of Huntington's disease (HD) registries and patient support organizations, genetic testing, and the discovery of a disease‐causing CAG repeat expansion changed the contours of genetic counseling for families with HD. It also reviews the guidelines, outcomes, ethical and laboratory challenges, and uptake of predictive, prenatal, and preimplantation testing, and it casts a vision for how clinicians can better make use of genetic counseling to reach a broader pool of families that may be affected by HD and to ensure that genetic counseling is associated with the best levels of care. © 2016 Wiley Periodicals, Inc.
The ANK3 gene and facial affect processing: An ERP study
Authors: Zhao Wan , Zhang Qiumei , Yu Ping , Zhang Zhifang , Chen Xiongying , Gu Huang , Zhai Jinguo , Chen Min , Du Boqi , Deng Xiaoxiang , Ji Feng , Wang Chuanyue , Xiang Yu‐Tao , Li Dawei , Wu Hongjie , Dong Qi , Luo Yuejia , Li Jun , Chen Chuansheng
Published: May 2016

ANK3 is one of the most promising candidate genes for bipolar disorder (BD). A polymorphism (rs10994336) within the ANK3 gene has been associated with BD in at least three genome‐wide association studies of BD [McGuffin et al., 2003; Kieseppä, 2004; Edvardsen et al., 2008]. Because facial affect processing is disrupted in patients with BD, the current study aimed to explore whether the BD risk alleles are associated with the N170, an early event‐related potential (ERP) component related to facial affect processing. We collected data from two independent samples of healthy individuals (Ns = 83 and 82, respectively) to test the association between rs10994336 and an early event‐related potential (ERP) component (N170) that is sensitive to facial affect processing. Repeated‐measures analysis of covariance in both samples consistently revealed significant main effects of rs10994336 genotype (Sample I: F (1, 72) = 7.24, P = 0.009; Sample II: F (1, 69) = 11.81, P = 0.001), but no significant interaction of genotype × electrodes (Ps > 0.05) or genotype × emotional conditions (Ps > 0.05). These results suggested that rs10994336 was linked to early ERP component reflecting facial structural encoding during facial affect processing. These results shed new light on the brain mechanism of this risk SNP and associated disorders such as BD. © 2016 Wiley Periodicals, Inc.
Peripheral blood eosinophilia correlates with hyperplastic nasal polyp growth
Authors: Drake Virginia E. , Rafaels Nicholas , Kim Jean
Published: May 2016

Background

Eosinophils are thought to play a significant role in nasal polyposis, but the exact mechanism by which they contribute to polyposis remains unclear. Therefore, we proposed to test the hypothesis that peripheral blood eosinophilia (PBE) is a surrogate and biomarker for polyp load. To do this, we examined whether PBE levels correlate with nasal polyp load in a longitudinal manner.

Methods

We retrospectively analyzed the fluctuation of PBE and nasal polyp load in each patient (n = 61) assessed preoperatively, 1–2 months postoperatively, and 3–12 months postoperatively. Nasal polyp load was assessed using computed tomography (CT) scan preoperatively and nasal endoscopy postoperatively. Correlation coefficients were analyzed using parametric statistics.

Results

There was a positive correlation between initial preoperative baseline PBE and CT scan staging of polyp load (r = 0.35, p < 0.01). When patients were analyzed longitudinally, we found that the change in PBE correlated with the change in nasal endoscopy scores obtained at or near the same timepoint (r = 0.82, p < 2.0 × 10−10). When nasal polyp load increased with time, we observed a stepwise increase in eosinophil counts (r = 0.37, p < 0.02).

Conclusions

PBE correlates with nasal polyp load. PBE levels may be used along with nasal endoscopy to prospectively follow nasal polyp load postoperatively in chronic rhinosinusitis patients with hyperplastic nasal polyposis who have eosinophilia, asthma, and/or aspirin‐exacerbated respiratory disease.
Emergent transcatheter arterial embolization for norovirus‐associated life‐threatening ulcer bleeding to achieve successful hemostasis in 2‐year‐old boy
Authors: Matsuoka Wakato , Kaku Noriyuki , Hirata Yuichiro , Lee Sooyoung , Akahoshi Tomohiko , Sugimori Hiroshi , Hayashida Makoto , Souzaki Ryota , Fujita Norihiro , Asayama Yoshiki , Taguchi Tomoaki , Takada Hidetoshi , Maehara Yoshihiko
Published: May 2016

Case

We report a 2‐year‐old boy with duodenal ulcer with active bleeding that occurred as a result of norovirus gastroenteritis. On admission, the patient presented with shock accompanied with vomiting and melena. Abdominal contrast enhanced computed tomography scan showed signs of duodenal bleeding.

Outcome

He was successfully treated with emergent transcatheter arterial embolization. After the treatment, endoscopic examination revealed duodenal ulcer and the stool norovirus antigen test was found to be positive. The patient recovered completely without any sequelae.

Conclusion

Life‐threatening duodenal ulcer bleeding in children can be caused by viral gastroenteritis. When endoscopic therapy is unsuccessful or difficult, in cases of small children, angiographic intervention can be a safe alternative treatment option of gastrointestinal bleeding.
Experimental measurement of flow distribution in a parallel mini‐channel fluidic network using PIV technique
Authors: Boutin Guillaume , Wei Min , Fan Yilin , Luo Lingai
Published: May 2016

Fluid flow distribution among parallel channels usually plays an important role on the global performance improvement of tubular process equipment, but remains difficult to be properly measured by experimental methods. This paper presents a systematic study on the measurement of flow distribution in a multi‐channel fluidic network using Particle Image Velocimetry (PIV) technique. For the precise measurement of flow‐rate in each individual channel, standard 2 dimensions, 2 components PIV technique is used to obtain velocity vectors on multiple sampling planes parallel to the flow direction, so as to reconstruct accurate velocity profiles on the cross‐sectional surface. Such procedure is repeated for every micro‐ (mini‐) channel to obtain the actual flow distribution properties in the fluidic network.

Pre‐test results on a double‐channel device indicate that the maximum possible deviation of PIV measurements is 13.1% with respect to those of a flange flowmeter, implying that the PIV technique is relatively accurate and reliable. PIV results on the flow distribution in a 15‐channel fluidic network are then compared with Computational Fluid Dynamics simulation results under the same working conditions. A quite good agreement could be observed. Moreover, the locations and sizes of vortices in the distributor have a significant influence on the flow distribution. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.
Biocompatible scaffolds composed of chemically crosslinked chitosan and gelatin for tissue engineering
Authors: Cañas Ana Isabel , Delgado Jean Paul , Gartner Carmiña
Published: May 2016

Chitosan‐based scaffolds are widely studied in tissue regeneration because of their biocompatibility and biodegradability. Scaffolds are obtained by different techniques and can be modified with other polymers allowing controlling their properties. This article discusses the assembling of three‐dimensional chitosan porous scaffolds blended with gelatin. Gelatin was used to enhance cells attachment due to the presence of cell adhesion motifs, while improving mechanical strength. 2,5‐dimethoxy‐2,5‐dihydrofurane (DHF) was used as the crosslinking agent, because it allowed to control the reaction kinetics through temperature, time and DHF concentration. The results indicate that scaffolds morphology, pore sizes and distribution, compressive moduli and biodegradation in vitro with lysozyme, can be customized with variations of gelatin content and crosslinking degree. Scaffolds were neither cytotoxic nor genotoxic for human keratinocytes, exhibiting cell–substrate interactions. Our findings demonstrated that chitosan–gelatin scaffolds crosslinked with DHF, as a new crosslinking agent, are suitable in tissue engineering applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43814.
9,10‐Dibromo‐N‐aryl‐9,10‐dihydro‐9,10‐[3,4]epipyrroloanthracene‐12,14‐diones: Synthesis and Investigation of Their Effects on Carbonic Anhydrase Isozymes I, II, IX, and XII
Authors: Göksu Haydar , Topal Meryem , Keskin Ali , Gültekin Mehmet S. , Çelik Murat , Gülçin İlhami , Tanc Muhammet , Supuran Claudiu T.
Published: May 2016

N‐substituted maleimides were synthesized from maleic anhydride and primary amines. 1,4‐Dibromo‐dibenzo[e,h]bicyclo‐[2,2,2]octane‐2,3‐dicarboximide derivatives (4a–f) were prepared by the [4+2] cycloaddition reaction of dibromoanthracenes with the N‐substituted maleimide derivatives. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the new derivatives were assayed against the human (h) isozymes hCA I, II, IX, and XII. All tested bicyclo dicarboximide derivatives exhibited excellent inhibitory effects in the nanomolar range, with Ki values in the range of 117.73–232.87 nM against hCA I and of 69.74–111.51 nM against hCA II, whereas they were low micromolar inhibitors against hCA IX and XII.
Facile Co‐Assembly of a Dipeptide‐Based Organogel toward Efficient Triplet–Triplet Annihilation Photonic Upconversion
Authors: Liu Xingcen , Fei Jinbo , Zhu Pengli , Li Junbai
Published: May 2016

By one‐step molecular co‐assembly, a diphenylalanine‐based photonic upconversion organogel was constructed within 20 seconds. Impressively, such an assembled system exhibits green‐to‐blue triplet–triplet annihilation upconversion with a relative quantum yield of 12 % even under ambient conditions
Robust Minimum Variance Lower Bound Estimation by Uncertainty Modeling Using Interval Type‐2 Fuzzy set
Authors: Alipouri Yousef , Poshtan Javad
Published: May 2016

The Minimum Variance Lower Bound (MVLB) represents the best achievable controller capability in a variance sense. Estimation of the MVLB for nonlinear systems confronts some difficulties. If one simply ignores these nonlinearities, there is the danger of over‐estimating the performance of the control loop in rejecting uncertainties. Assuming that almost all models have uncertainties, in this paper, the MVLB has been estimated considering three types of uncertainties: structural, parametric, and algorithmic. To achieve accurate estimation of the MVLB an interval type‐2 fuzzy set has been utilized. This paper utilizes a strategy for modeling of symmetric interval type‐2 fuzzy sets using their uncertainty degrees. Then, based on this uncertainty measure, one method to construct interval type‐2 fuzzy set models using the uncertain interval data is introduced. Finally, simulation studies demonstrate the effectiveness of the proposed control scheme.
Determining the association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and genomic DNA methylation level: A meta‐analysis
Authors: Wang Li , Shangguan Shaofang , Chang Shaoyan , Yu Xin , Wang Zhen , Lu Xiaolin , Wu Lihua , Zhang Ting
Published: May 2016

Background

The methylenetetrahydrofolate reductase (MTHFR) polymorphism is a risk factor for neural tube defects. C677T and A1298C MTHFR polymorphisms produce an enzyme with reduced folate‐related one carbon metabolism, and this has been associated with aberrant methylation modifications in DNA and protein.

Methods

A meta‐analysis was conducted to assess the association between MTHFR C677T/A1298C genotypes and global genomic methylation.

Results

Eleven studies met the inclusion criteria. Of these, 10 were performed on C677T MTHFR genotypes and 6 were performed on A1298C MTHFR genotypes. Our results did not indicate any correlation between global methylation and MTHFR A1298C, C677T polymorphisms.

Conclusion

The results of our study provide evidence to assess the global methylation modification alterations of MTHFR polymorphisms among individuals. However, our data did not found any conceivable proof supporting the hypothesis that common variant of MTHFR A1298C, C677T contributes to methylation modification. Birth Defects Research (Part A) 106:667–674, 2016. © 2016 Wiley Periodicals, Inc.
Comparative dosimetry for children and rodents exposed to extremely low‐frequency magnetic fields
Authors: Gong Yijian , Capstick Myles , Dasenbrock Clemens , Fedrowitz Maren , Cobaleda Cesar , Sánchez‐García Isidro , Kuster Niels
Published: May 2016

We describe a method to correlate E‐fields induced by exposure to extremely low frequency magnetic fields in laboratory mice and rats during in vivo experiments to those induced in children. Four different approaches of mapping relative dose rates between humans and rodents are herein proposed and analyzed. Based on these mapping methods and volume averaging guidelines published by the International Commission on Non‐Ionizing Radiation Protection (ICNRP) in 2010, maximum and median induced field values for whole body and for tissues of children and rodents were evaluated and compared. Median induced electric fields in children younger than 10 years old are in the range 5.9–8.5 V/m per T (±0.4 dB). Maximum induced electric fields, generally in the skin, are between 48 V/m and 228 V/m per T (±4 dB). To achieve induced electric fields of comparable magnitude in rodents, external magnetic field must be increased by a factor of 4.0 (±2.6 dB) for rats and 7.4 (±1.8 dB) for mice. Meanwhile, to achieve comparable magnetic field dose in rodents, ratio is close to one. These induced field dose rates for children and rodents can be used to quantifiably compare experimental data from in vivo studies with data on exposure of children from epidemiological studies, such as for leukemia. Bioelectromagnetics. 37:310–322, 2016. © 2016 Wiley Periodicals, Inc.
P53 and the defenses against genome instability caused by transposons and repetitive elements
Authors: Levine Arnold J. , Ting David T. , Greenbaum Benjamin D.
Published: May 2016

The recent publication by Wylie et al. is reviewed, demonstrating that the p53 protein regulates the movement of transposons. While this work presents genetic evidence for a piRNA‐mediated p53 interaction with transposons inDrosophilaand zebrafish, it is herein placed in the context of a decade or so of additional work that demonstrated a role for p53 in regulating transposons and other repetitive elements. The line of thought in those studies began with the observation that transposons damage DNA and p53 regulates DNA damage. The presence of transposon movement can increase the rate of evolution in the germ line and alter genes involved in signal transduction pathways. Transposition can also play an important role in cancers where the p53 gene function is often mutated. This is particularly interesting as recent work has shown that de‐repression of repetitive elements in cancer has important consequences for the immune system and tumor microenvironment.
YAP and TAZ in epithelial stem cells: A sensor for cell polarity, mechanical forces and tissue damage
Authors: Elbediwy Ahmed , Vincent‐Mistiaen Zoé I. , Thompson Barry J.
Published: May 2016

The YAP/TAZ family of transcriptional co‐activators drives cell proliferation in epithelial tissues and cancers. Yet, how YAP and TAZ are physiologically regulated remains unclear. Here we review recent reports that YAP and TAZ act primarily as sensors of epithelial cell polarity, being inhibited when cells differentiate an apical membrane domain, and being activated when cells contact the extracellular matrix via their basal membrane domain. Apical signalling occurs via the canonical Crumbs/CRB‐Hippo/MST‐Warts/LATS kinase cascade to phosphorylate and inhibit YAP/TAZ. Basal signalling occurs via Integrins and Src family kinases to phosphorylate and activate YAP/TAZ. Thus, YAP/TAZ is localised to the nucleus in basal stem/progenitor cells and cytoplasm in differentiated squamous cells or columnar cells. In addition, other signals such as mechanical forces, tissue damage and possibly receptor tyrosine kinases (RTKs) can influence MST‐LATS or Src family kinase activity to modulate YAP/TAZ activity.
Statin use after intracerebral hemorrhage: a 10‐year nationwide cohort study
Authors: Tai Shu‐Yu , Lin Feng‐Cheng , Lee Chung‐Yin , Chang Chai‐Jan , Wu Ming‐Tsang , Chien Chen‐Yu
Published: May 2016

Introduction

Although statin therapy is beneficial to patients with ischemic stroke, statin use, and intracerebral hemorrhage (ICH) remain a concern. ICH survivors commonly have comorbid cardiovascular risk factors that would otherwise warrant cholesterol‐lowering medication, thus emphasizing the importance of assessing the characteristics of statin therapy in this population.

Methods

We performed a cohort study by using 10 years of data collected from the National Health Insurance Research Database in Taiwan. We enrolled 726 patients admitted for newly diagnosed ICH from January 1, 2001 to December 31, 2010. The patients were categorized into high‐ (92), moderate‐ (545), and low‐intensity (89) statin groups, and into hydrophilic (295) and lipophilic (431) statin groups. The composite outcomes included all‐cause mortality, recurrent ICH, ischemic stroke, transient ischemic attack, and acute coronary events.

Results

The patients in the low‐intensity group did not differ significantly from the patients in the high‐intensity group in risk of all‐cause mortality (adjusted hazard ratio [aHR] = 0.65, 95% confidence interval [CI] = 0.28–1.55) and recurrent ICH (aHR = 0.66, 95% CI = 0.30–1.44). In contrast, the patients in the hydrophilic group had a significantly lower risk of recurrent ICH than did those in the lipophilic group (aHR = 0.69, 95% CI = 0.48–0.99). We determined no significant differences in other composite endpoints between hydrophilic and lipophilic statin use.

Conclusion

Hydrophilic statin therapy is associated with a reduced risk of recurrent ICH in post‐ICH patients. The intensity of statin use had no significant effect on recurrent ICH or other components of the composite outcome. Additional studies are required to clarify the biological mechanisms underlying these observations.
Mechanisms of Enhanced Catalysis in Enzyme–DNA Nanostructures Revealed through Molecular Simulations and Experimental Analysis
Authors: Gao Yingning , Roberts Christopher C. , Toop Aaron , Chang Chia‐en A. , Wheeldon Ian
Published: May 2016

Understanding and controlling the molecular interactions between enzyme substrates and DNA nanostructures has important implications in the advancement of enzyme–DNA technologies as solutions in biocatalysis. Such hybrid nanostructures can be used to create enzyme systems with enhanced catalysis by controlling the local chemical and physical environments and the spatial organization of enzymes. Here we have used molecular simulations with corresponding experiments to describe a mechanism of enhanced catalysis due to locally increased substrate concentrations. With a series of DNA nanostructures conjugated to horseradish peroxidase, we show that binding interactions between substrates and the DNA structures can increase local substrate concentrations. Increased local substrate concentrations in HRP(DNA) nanostructures resulted in 2.9‐ and 2.4‐fold decreases in the apparent Michaelis constants of tetramethylbenzidine and 4‐aminophenol, substrates of HRP with tunable binding interactions to DNA nanostructures with dissociation constants in the micromolar range. Molecular simulations and kinetic analysis also revealed that increased local substrate concentrations enhanced the rates of substrate association. Identification of the mechanism of increased local concentration of substrates in close proximity to enzymes and their active sites adds to our understanding of nanostructured biocatalysis from which we can develop guidelines for enhancing catalysis in rationally designed systems.
Low‐temperature Fischer‐Tropsch synthesis using plasma‐synthesized nanometric Co/C and Fe/C catalysts
Authors: Aluha James , Braidy Nadi , Dalai Ajay , Abatzoglou Nicolas
Published: May 2016

In this study, two analogous nanometric catalysts consisting of carbon‐supported cobalt or iron (Co/C and Fe/C) were synthesized by plasma and tested for Fischer‐Tropsch synthesis (FTS) in a continuously‐stirred tank slurry reactor (CSTSR). Being pyrophoric in nature, these new materials were reduced in situ at 673 K (400 °C) for 24 h using pure H2 gas. The FTS reaction was conducted at 493 K (220 °C), 2000 kPa pressure, and gas hourly space velocity (GHSV) of 3600 mL ·  for 24 h, using a feed stream of 0.6 L/L (60 vol %) H2 and 0.3 L/L (30 vol %) CO, with 0.1 L/L (10 vol %) Ar for mass balance determination. Devoid of promoters and under similar reaction conditions, the Co/C catalyst showed higher CO conversion (42 %) than the Fe/C (25 %), benchmarked against the commercial Fe‐NanoCat® (32 %). Co/C was more selective toward gasoline production, while Fe/C was more selective toward the diesel fraction. From transmission electron microscopy (TEM) analysis, no significant change in the mean particle size (∼12 nm) was observed in the plasma‐synthesized catalysts before and after FTS reaction, implying that the catalysts did not sinter. Additionally, there were no internal mass transport limitations in these catalysts, making them favourable for FTS. Besides metallic species, X‐ray diffraction (XRD) analysis indicated the presence of carbides in fresh catalysts (Fe3C in Fe/C and Co3C in Co/C). Magnetite (Fe3O4) was the most prevalent phase in the used Fe‐NanoCat® sample, a phase that was below the detection limits of XRD in the used plasma‐synthesized Fe/C sample.
Association Between Very Low Levels of High‐Density Lipoprotein Cholesterol and Long‐term Outcomes of Patients With Acute Coronary Syndrome Treated Without Revascularization: Insights From the TRILOGY ACS Trial
Authors: Hagström Emil , Roe Matthew T. , Hafley Gail , Neely Megan L. , Sidhu Mandeep S. , Winters Kenneth J. , Prabhakaran Dorairaj , White Harvey D. , Armstrong Paul W. , Fox Keith A.A. , Ohman E. Magnus , Boden William E. ,   for the TRILOGY ACS Investigators
Published: May 2016

Background

Low levels of high‐density lipoprotein cholesterol (HDL‐C; <40 mg/dL) are associated with increased risk of cardiovascular events, but it is unclear whether lower thresholds (<30 mg/dL) are associated with increased hazard.

Hypothesis

Very low levels of HDL‐C may provide prognostic information in acute coronary syndrome (ACS) patients treated medically without revascularization.

Methods

We examined data from 9064/9326 ACS patients enrolled in the TRILOGY ACS trial. Participants were randomized to clopidogrel or prasugrel plus aspirin. Study treatments continued for 6 to 30 months. Relationships between baseline HDL‐C and the composite of cardiovascular death, myocardial infarction (MI), or stroke, and individual endpoints of death (cardiovascular and all‐cause), MI, and stroke, adjusted for baseline characteristics through 30 months, were analyzed. The HDL‐C was evaluated as a dichotomous variable—very low (<30 mg/dL) vs higher (≥30 mg/dL)—and continuously.

Results

Median baseline HDL‐C was 42 mg/dL (interquartile range, 34–49 mg/dL) with little variation over time. Frequency of the composite endpoint was similar for very low vs higher baseline HDL‐C, with no risk difference between groups (hazard ratio [HR]: 1.13, 95% confidence interval [CI]: 0.95‐1.34). Similar findings were seen for MI and stroke. However, risks for cardiovascular (HR: 1.42, 95% CI: 1.13‐1.78) and all‐cause death (HR: 1.36, 95% CI: 1.11‐1.67) were higher in patients with very low baseline HDL‐C.

Conclusions

Medically managed ACS patients with very low baseline HDL‐C levels have higher risk of long‐term cardiovascular and all‐cause death but similar risks for nonfatal ischemic outcomes vs patients with higher baseline HDL‐C.
Monitoring of Daily Body Weight and Intrathoracic Impedance in Heart Failure Patients With a High Risk of Volume Overload Decompensation
Authors: Gudmundsson Kristjan , Lyngå Patrik , Rosenqvist Mårten , Braunschweig Frieder
Published: May 2016

Background

Decompensation is frequent in heart failure (HF) patients and predicts poor prognosis.

Hypothesis

Volume‐overload events in HF patients are preceded by changes in intrathoracic impedance (Z) and body weight (BW); monitoring these parameters may be useful to predict decompensation.

Methods

Forty‐three HF patients (LVEF 25% ± 12%) with a recent HF event and an implantable cardioverter‐defibrillator providing daily Z were equipped with telemonitoring scales submitting daily BW. Changes in BW and Z 30 days prior to major (HF hospitalization) and minor (ambulatory adjustment of diuretics) were analyzed.

Results

During median of 427 days follow‐up 25 major and 41 minor events occurred. Z decreased by −4.8 (95% confidence interval [CI]: CI −6.7 to −3.0) and −4.3 (95% CI: −5.5 to −3.2) within 30 days prior to major and minor events respectively (P < 0.001). BW increased before major events by 2.3 kg (95% CI: 1.0 to 3.5, P < 0.01) and minor events 1 kg (95% CI: 0.5 to 1.4, P < 0.001). Sensitivity of Z for major/minor HF events was 83.3% (95% CI: 71.7 to 91.0) and for BW 43.9% (95% CI: 31.9 to 56.7). The unexplained detection rate per patient‐year was 1.6 (interquartile range [IQR], 0–3.1) for Z and 4.8 (IQR 1.6–11.1) for BW. Combined Z and BW sensitivity was 42.4% (95% CI: 30.6 to 55.2) and unexplained detection rate was 0.8 (IQR, 0–1.5) per patient‐year.

Conclusions

Decompensation is marked by a decrease in Z and increase in BW the preceding 30 days. Monitoring of Z predicts HF decompensations with better sensitivity and lower unexplained detection rate than BW.
In Hypertrophic Cardiomyopathy, the Spatial Peaks QRS‐T Angle Identifies Those With Sustained Ventricular Arrhythmias
Authors: Cortez Daniel , Graw Sharon , Mestroni Luisa
Published: May 2016

Background

The spatial peaks QRS‐T (SPQRS‐T) angle differentiates hypertrophic cardiomyopathy (HCM) patients from controls. Increased angle confers arrhythmia risk in other populations.

Hypothesis

We predict that the SPQRS‐T angle will identify HCM patients with sustained ventricular arrhythmias (VAs) and those with New York Heart Association class III/IV heart failure.

Methods

Corrected QT interval, QRS duration, and SPQRS‐T angle were assessed in HCM patients with VAs (>30 seconds) and those without VAs.

Results

One hundred HCM patients (mean age, 32.7 ± 17.2 years) were assessed. Twenty patients had VAs. The corrected QT interval identified VA (P = 0.018) and at 460 ms gave positive and negative predictive values of 28.6% and 83.3%, respectively, and an odds ratio of 2.0 (95% confidence interval: 0.7‐5.6). The SPQRS‐T angle differentiated VA from no VA (P < 0.001) and at 124.1 degrees gave positive and negative predictive values and an odds ratio of 36.7%, 96.1%, and 14.2 (95% confidence interval: 3.1‐65.6), respectively.

Conclusions

The SPQRS‐T angle best differentiated patients with VAs.
Association of Physical Fitness With the Risk of Atrial Fibrillation: A Systematic Review and Meta‐Analysis
Authors: Zhu Wengen , Shen Yang , Zhou Qiongqiong , Xu Zhenyan , Huang Lin , Chen Qi , Hong Kui
Published: May 2016

Several studies have investigated the role of physical fitness in atrial fibrillation (AF), but the results remain controversial. We aimed to estimate the association between physical fitness and risk of AF. We comprehensively retrieved data from the Cochrane Library, PubMed, and Embase databases until February 29, 2016, for studies evaluating the association of physical fitness with the risk of AF. Data were abstracted from included studies, and effect estimates were pooled using a random‐effects model. Six studies with a total of 205 094 participants and 15 919 AF cases fulfilled the inclusion criteria. When physical fitness was assessed as a continuous variable, per incremental increase of physical fitness was associated with a 9% reduced risk of AF (risk ratio [RR]: 0.91, 95% confidence interval [CI]: 0.84‐1.00, P = 0.05). When physical fitness was assessed as a categorical variable, the risk of AF was significantly reduced (RR: 0.51, 95% CI: 0.28‐0.91, P = 0.02) in individuals with the highest level of physical fitness compared with those with the lowest level. The intermediate vs the lowest level of physical fitness was associated with a 28% reduced risk of AF (RR: 0.72, 95% CI: 0.56‐0.93, P = 0.01). The sensitivity analysis indicated that these results were stable. Notably, there was evidence of statistical heterogeneity across studies; therefore, we should interpret the results cautiously. In conclusion, published literature supports that a higher level of physical fitness is associated with a lower risk of AF. Further studies should be performed to confirm these findings.
The value of a transformation zone component in anal cytology to detect HSIL
Authors: Roberts Jennifer M. , Jin Fengyi , Thurloe Julia K. , Ekman Deborah , Adams Marjorie K. , McDonald Ross L. , Biro Clare , Poynten I. Mary , Grulich Andrew E. , Farnsworth Annabelle ,   on behalf of The Study of the Prevention of Anal Cancer (SPANC) Study Team
Published: May 2016

BACKGROUND

In a cytology‐based screening program intended to prevent anal cancer, the anal transformation zone (TZ) should be adequately sampled because it is the site most susceptible to the development of the cancer precursor, high‐grade squamous intraepithelial lesion (HSIL). An adequate TZ component is defined as comprising at least 10 rectal columnar or squamous metaplastic cells. In the current study, the authors examined whether the presence of a TZ component in anal cytology correlated with the detection of histological HSIL.

METHODS

In a natural history study of anal human papillomavirus infection in homosexual men, all participants underwent liquid‐based cytology and high‐resolution anoscopy (HRA) with or without biopsy at each visit. True‐negative cytology (negative cytology with non‐HSIL biopsy or negative HRA), false‐negative cytology (negative cytology with HSIL biopsy), and true‐positive cytology (abnormal cytology with HSIL biopsy) were compared with regard to the presence or absence of a TZ component.

RESULTS

Of 617 participants, baseline results included 155 true‐positive results, 191 true‐negative results, and 31 false‐negative results. The absence of an adequate TZ component was found to be significantly higher for false‐negative (32.3%) than for either true‐positive (11.0%; P = .0034) or true‐negative (13.1%; P = .0089) results.

CONCLUSIONS

Significantly more false‐negative cases lacked a TZ component compared with either true‐positive or true‐negative cases. TZ cells may be an important indicator of sample quality for anal cytology because, unlike cervical sampling, the anal canal is not visualized during cytology sampling. Cancer Cytopathol 2016;124:596‐601. © 2016 American Cancer Society.
Quantitative phase imaging to improve the diagnostic accuracy of urine cytology
Authors: Pham Hoa V. , Pantanowitz Liron , Liu Yang
Published: May 2016

BACKGROUND

A definitive diagnosis of urothelial carcinoma in urine cytology is often challenging and subjective. Many urine cytology samples receive an indeterminate diagnosis. Ancillary techniques such as fluorescence in situ hybridization (FISH) have been used to improve the diagnostic sensitivity, but FISH is not approved as a routine screening test, and the complex fluorescent staining protocol also limits its widespread clinical use. Quantitative phase imaging (QPI) is an emerging technology allowing accurate measurements of the single‐cell dry mass. This study was undertaken to explore the ability of QPI to improve the diagnostic accuracy of urine cytology for malignancy.

METHODS

QPI was performed on unstained, ThinPrep‐prepared urine cytology slides from 28 patients with 4 categories of cytological diagnoses (negative, atypical, suspicious, and positive for malignancy). The nuclear/cell dry mass, the entropy, and the nucleus‐to‐cell mass ratio were calculated for several hundred cells for each patient, and they were then correlated with the follow‐up diagnoses.

RESULTS

The nuclear mass and nuclear mass entropy of urothelial cells showed significant differences between negative and positive groups. These data showed a progressive increase from patients with negative diagnosis, to patients with atypical/suspicious and positive cytologic diagnosis. Most importantly, among the patients in the atypical and suspicious diagnosis, the nuclear mass and its entropy were significantly higher for those patients with a follow‐up diagnosis of malignancy than those patients without a subsequent follow‐up diagnosis of malignancy.

CONCLUSIONS

QPI shows potential for improving the diagnostic accuracy of urine cytology, especially for indeterminate cases, and should be further evaluated as an ancillary test for urine cytology. Cancer Cytopathol 2016;124:641–50. © 2016 American Cancer Society.
Day‐ahead price forecasting based on hybrid prediction model
Authors: Olamaee Javad , Mohammadi Mohsen , Noruzi Alireza , Hosseini Seyed Mohammad Hassan
Published: May 2016

Short‐Term Price Forecast is a key issue for operation of both regulated power systems and electricity markets. Energy price forecast is the key information for generating companies to prepare their bids in the electricity markets. However, this forecasting problem is complex due to nonlinear, nonstationary, and time variant behavior of electricity price time series. So, in this article, the forecast model includes wavelet transform, autoregressive integrated moving average, and radial basis function neural networks (RBFN) is presented. Also, an intelligent algorithm is applied to optimize the RBFN structure, which adapts it to the specified training set, reduce computational complexity and avoids over fitting. Effectiveness of the proposed method is applied for price forecasting of electricity market of mainland Spain and its results are compared with the results of several other price forecast methods. These comparisons confirm the validity of the developed approach. © 2016 Wiley Periodicals, Inc. Complexity 21: 156–164, 2016
Analyzing Quantum Correlations Made Simple
Authors: Dornheim T. , Thomsen H. , Ludwig P. , Filinov A. , Bonitz M.
Published: May 2016

The understanding of correlations in degenerate nonideal many‐particle systems is complex and theoretically challenging. Using the recently proposed permutation blocking path integral Monte Carlo (PB‐PIMC) scheme, which allows for an exact treatment of many‐body correlations, we study the influence of quantum statistics in a confined few‐particle Coulomb (quantum dot) system. As a versatile tool to gain insight into the internal structure of correlated many‐body systems, the application of triple correlation functions is extended to quantum systems. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Monte Carlo Simulation of Partially Ionized Hydrogen Plasmas
Authors: Cordes C. , Bornath Th. , Redmer R.
Published: May 2016

A Monte Carlo code has been developed for the interaction of initially neutral systems with intense ultra‐short laser pulses. Photoionization creates immediately a partially ionized, non‐equilibrium plasma for which the relevant scattering processes are included. In this way the absorption of the laser energy in the plasma and the evolution of the non‐equilibrium electron distribution function during the laser pulse is described. Furthermore, the relaxation into an equilibrium state can be studied for longer time scales. As an example we consider the interaction of a cold liquid hydrogen jet with intense, ultra‐short free electron laser pulses in the extreme ultraviolet spectral range. The corresponding spectrum of the Thomson self‐scattering is calculated using the non‐equilibrium electron distribution functions extracted from the Monte Carlo simulations. We compare with benchmarking experiments performed at the free electron laser facility FLASH. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Linking metacommunity paradigms to spatial coexistence mechanisms
Authors: Shoemaker Lauren G. , Melbourne Brett A.
Published: May 2016

Four metacommunity paradigms—usually called neutral, species sorting, mass effects, and patch dynamics, respectively—are widely used for empirical and theoretical studies of spatial community dynamics. The paradigm framework highlights key ecological mechanisms operating in metacommunities, such as dispersal limitation, competition‐colonization tradeoffs, or species equivalencies. However, differences in coexistence mechanisms between the paradigms and in situations with combined influences of multiple paradigms are not well understood. Here, we create a common model for competitive metacommunities, with unique parameterizations for each metacommunity paradigm and for scenarios with multiple paradigms operating simultaneously. We derive analytical expressions for the strength of Chesson's spatial coexistence mechanisms and quantify these for each paradigm via simulation. For our model, fitness–density covariance, a concentration effect measuring the importance of intraspecific aggregation of individuals, is the dominant coexistence mechanism in all three niche‐based metacommunity paradigms. Increased dispersal between patches erodes intraspecific aggregation, leading to lower coexistence strength in the mass effects paradigm compared to species sorting. Our analysis demonstrates the potential importance of aggregation of individuals (fitness–density covariance) over co‐variation in abiotic environments and competition between species (the storage effect), as fitness–density covariance can be stronger than the storage effect and is the sole stabilizing mechanism in the patch dynamics paradigm. As expected, stable coexistence does not occur in the neutral paradigm, which requires species to be equal and emphasizes the role of stochasticity. We show that stochasticity also plays an important role in niche‐structured metacommunities by altering coexistence strength. We conclude that Chesson's spatial coexistence mechanisms provide a flexible framework for comparing metacommunities of varying complexity.