bluuebunny/crossref_metadata_2025 huggingface dataset:
Radiative leptonic decay B → γℓνℓ with subleading power corrections
Authors: Beneke M. , Braun V. M. , Ji Yao , Wei Yan-Bing
Published: July 2018

Abstract

We reconsider the QCD predictions for the radiative decayB→ γℓνℓwith an energetic photon in the final state by taking into account the 1/Eγ,1/mbpower-suppressed hard-collinear and soft corrections from higher-twistB-meson light-cone distribution amplitudes (LCDAs). The soft contribution is estimated through a dispersion relation and light-cone QCD sum rules. The analysis of theoretical uncertainties and the dependence of the decay form factors on the leading-twist LCDAϕ+(ω) shows that the latter dominates. The radiative leptonic decay is therefore well suited to constrain the parameters ofϕ+(ω), including the first inverse moment, 1/λB, from the expected high-statistics data of the BELLE II experiment.
Surface-displayed porcine reproductive and respiratory syndrome virus from cell culture onto gram-positive enhancer matrix particles
Authors: Li Lan , Qiao Xuwen , Chen Jin , Zhang Yuanpeng , Zheng Qisheng , Hou Jibo
Published: July 2018

Vaccine immunization is now one of the most effective ways to control porcine reproductive and respiratory syndrome virus (PRRSV) infection. Impurity is one of the main factors affecting vaccine safety and efficacy. Here we present a novel innovative PRRSV purification approach based on surface display technology. First, a bifunctional protein PA-GRFT (protein anchor-griffithsin), the crucial factor in the purification process, was successfully produced in Escherichia coli yielding 80 mg/L of broth culture. Then PRRSV purification was performed by incubation of PA-GRFT with PRRSV and gram-positive enhancer matrix (GEM) particles, followed by centrifugation to collect virions loaded onto GEM particles. Our results showed that most of the bulk impurities had been removed, and PA-GRFT could capture PRRSV onto GEM particles. Our lactic acid bacteria-based purification method, which is promising as ease of operation, low cost and easy to scale-up, may represent a candidate method for the large-scale purification of this virus for vaccine production.
Long‐term complications of glycogen storage disease type Ia in the canine model treated with gene replacement therapy
Authors: Brooks Elizabeth D. , Landau Dustin J. , Everitt Jeffrey I. , Brown Talmage T. , Grady Kylie M. , Waskowicz Lauren , Bass Cameron R. , D'Angelo John , Asfaw Yohannes G. , Williams Kyha , Kishnani Priya S. , Koeberl Dwight D.
Published: July 2018

Background

Glycogen storage disease type Ia (GSD Ia) in dogs closely resembles human GSD Ia. Untreated patients with GSD Ia develop complications associated with glucose‐6‐phosphatase (G6Pase) deficiency. Survival of human patients on intensive nutritional management has improved; however, long‐term complications persist including renal failure, nephrolithiasis, hepatocellular adenomas (HCA), and a high risk for hepatocellular carcinoma (HCC). Affected dogs fail to thrive with dietary therapy alone. Treatment with gene replacement therapy using adeno‐associated viral vectors (AAV) expressing G6Pase has greatly prolonged life and prevented hypoglycemia in affected dogs. However, long‐term complications have not been described to date.

Methods

Five GSD Ia‐affected dogs treated with AAV‐G6Pase were evaluated. Dogs were euthanized due to reaching humane endpoints related to liver and/or kidney involvement, at 4 to 8 years of life. Necropsies were performed and tissues were analyzed.

Results

Four dogs had liver tumors consistent with HCA and HCC. Three dogs developed renal failure, but all dogs exhibited progressive kidney disease histologically. Urolithiasis was detected in two dogs; uroliths were composed of calcium oxalate and calcium phosphate. One affected and one carrier dog had polycystic ovarian disease. Bone mineral density was not significantly affected.

Conclusions

Here, we show that the canine GSD Ia model demonstrates similar long‐term complications as GSD Ia patients in spite of gene replacement therapy. Further development of gene therapy is needed to develop a more effective treatment to prevent long‐term complications of GSD Ia.
Minimotifs dysfunction is pervasive in neurodegenerative disorders
Authors: Sharma Surbhi , Young Richard J. , Chen Jingchun , Chen Xiangning , Oh Edwin C. , Schiller Martin R.
Published: July 2018

Minimotifs are modular contiguous peptide sequences in proteins that are important for posttranslational modifications, binding to other molecules, and trafficking to specific subcellular compartments. Some molecular functions of proteins in cellular pathways can be predicted from minimotif consensus sequences identified through experimentation. While a role for minimotifs in regulating signal transduction and gene regulation during disease pathogenesis (such as infectious diseases and cancer) is established, the therapeutic use of minimotif mimetic drugs is limited. In this review, we discuss a general theme identifying a pervasive role of minimotifs in the pathomechanism of neurodegenerative diseases. Beyond their longstanding history in the genetics of familial neurodegeneration, minimotifs are also major players in neurotoxic protein aggregation, aberrant protein trafficking, and epigenetic regulation. Generalizing the importance of minimotifs in neurodegenerative diseases offers a new perspective for the future study of neurodegenerative mechanisms and the investigation of new therapeutics.
The Contexts of Electoral Accountability: Electoral Integrity Performance Voting in 23 Democracies
Authors: Fumarola Andrea
Published: July 2018

Electoral accountability is typically identified with retrospective economic voting even though it is widely recognized that explaining electors’ assignment of responsibility also implies considering issues other than the economy. Recently, scholars have also stressed the role of election quality in contributing to democratic legitimacy of elected authorities. In this perspective, electoral integrity as a valence issue would influence voters’ behaviour, structuring attitudes about accountability in substantial ways. This effect would also be moderated by individual- and country-level factors. I test these assumptions in 23 countries worldwide using a multilevel analysis of data from the sixth wave of the World Values Survey. Results indicate that the strength of the link between perceptions of electoral integrity and vote for the incumbent seems to be affected by individual characteristics such as partisanship, while it is also moderated by specific contextual characteristics such as government clarity of responsibility and pluralism of the media.
La Mesure des Étoiles Doubles Visuelles
Authors: Couteau Paul
Published: July 2018

La dÉcouverte des Étoiles doubles visuelles a ÉtÉ une des consÉquences logiques du developpement de I'astromÉtrie Équatoriale. L'Étude de ces objets est fonction du temps et de l'abondance des dÉcouvertes qui dÉpend, elle aussi, du temps. II en rÉsulte que nos connaissances dans ce domaine croissent en progression arithmÉtique, au lieu de suivre une progression gÉomÉtrique comme la plupart des spÉcialites astrophysiques qui dÉpendent davantage de mÉthodes que du temps.
Discovery and Measurement of Double Stars by Lunar Occultations
Authors: Edward Nather R. , Evans David S.
Published: July 2018

When a star is occulted by the dark limb of the Moon its apparent intensity drops to zero very quickly. MacMahon (1909) proposed that the time of disappearance would measure the diameter of the star, but Eddington (1909) demonstrated that diffraction effects at the lunar limb would lengthen the apparent time of disappearance to about 20 msec, and suggested that these effects would greatly limit the usefulness of the technique.
Some Results of the Spectroscopic Study of Four Close Binary Systems of Early Spectral Types
Authors: Galkina T. S.
Published: July 2018

It is necessary to have quantitative estimates of the intensity of lines (both absorption and emission) to obtain the physical parameters of the atmosphere of components.

Some years ago at the Crimean observatory we began the spectroscopic investigation of close binary systems of the early spectral type with components WR, Of, O, B to try and obtain more quantitative information from the study of the spectra of the components.
Les Erreurs Affectant Les Periodes, Les Demi-Grands Axes et les Masses Totales des Couples Visuels Orbitaux
Authors: Dommanget J.
Published: July 2018

Soit Δt, Fintervalle de temps couvert par les observations ayant permis le calcul des éléments orbitaux d'une étoile double visuelle. Soient P, sa période et a", son demigrand axe.
Systematic Errors in the Photographic Positions of Double Stars at the Sproul Observatory
Authors: Lee Lippincott Sarah
Published: July 2018

The long range program of the Sproul Observatory initiated in 1937 by Peter van de Kamp has been primarily devoted to a detailed astrometric study of the positions of nearby stars from photographs taken with the 24-in. refractor. The accumulation of plates over a long time interval provides the opportunity for finding perturbations of small amplitude leading to the discovery of unseen companions.
High-intensity pulsed ion beam composition and the energy spectrum using the time-of-flight method
Authors: Pushkarev A. I. , Isakova Y. I. , Prima A. I.
Published: July 2018

The paper describes a technique for operative control of the high-intensity pulsed ion beam parameters. The time-of-flight diagnostics uses one high-speed Faraday cup sensor with magnetic cut-off of low-energy electrons. The technique makes it possible to determine the composition of the beam (the type of ions and the degree of ionization), the absolute values of the current density of ions and the energy spectrum for each type of ions with an error of <±10%. The technique was tested at different pulsed ion accelerators and ion diodes both with self-magnetic insulation (accelerating voltage of 200–250 kV, ion current density of 20–300 A/cm2) and external magnetic insulation of the electrons (400–500 kV, 200 A/cm2). The article presents a comparative analysis of two types of Faraday cups with magnetic cut-off of the electrons and with electric bias.
Massive decline of the world’s largest king penguin colony at Ile aux Cochons, Crozet
Authors: Weimerskirch Henri , Le Bouard Fabrice , Ryan Peter G. , Bost C.A.
Published: July 2018

King penguins (Aptenodytes patagonicusMiller) are major consumers in the Southern Ocean. The colony at Ile aux Cochons, Iles Crozet, in the southern Indian Ocean was known in the 1980s as the largest king penguin colony and the second largest penguin colony in the world. However, there have not been any recent estimates of this colony. Aerial photographs taken from a helicopter, and satellite images were used to report on changes in the colony and population sizes over the past 50 years. The colony has declined by 88% over the past 35 years, fromc.500 000 pairs to 60 000 pairs. The possible causes of this decline were explored but no plausible explanation for such an unprecedented decrease in penguin populations was found. The study highlights the use of satellite imagery as a non-invasive technique for population monitoring, and stresses the need for further research on the causes of this alarming trend in this colony.
Structural Conditions for Interdisciplinarity
Authors: Engwall Lars
Published: July 2018

Analysing structural conditions for interdisciplinarity, this paper focuses on the characteristics of four factors in the organization of the sciences: disciplines, institutions, rewards and funding. It is argued that interdisciplinarity is less likely to involve disciplines that are strongly integrated, i.e. where task uncertainty is low and the dependence among researchers is high. Likewise, it is claimed that interdisciplinarity is likely to be hampered by strong departmental organization structures. Interdisciplinarity is also considered to become less likely as quality control is specifically discipline oriented and also when funding is concentrated and in the hands of scientific elites. In contrast, interdisciplinary research may be found in research environments with weakly integrated disciplines in institutions with weak or no departmental structures, and where disciplinary reward systems are weak in systems with a variety of funding.
Offspring sex ratio and reproductive tactics of Leptocybe invasa (Hymenoptera: Eulophidae): testing the effect of environmental characteristics
Authors: Zheng Xia-Lin , Lin Kai , Huang Zong-You , Li Jun , Yang Zhen-De , Yang Xiu-Hao , Lu Wen
Published: July 2018

Environmental characteristics (for example, temperature, photoperiod) as seasonal cues can affect the offspring sex ratio and reproductive tactics of many hymenopteran insects.Leptocybe invasaFisher & La Salle is the most critical invasive insect pest ofEucalyptusspp. in the world and displays thelytokous reproduction. In the current study, we studied the effects of temperature and photoperiod on offspring sex ratio and reproductive tactics inL. invasa. Results show that sex ratio (female: male) ofL. invasawas under 15, 25 and 35 °C with both L 12: D 12 and L 16: D 8, and cold and thermal acclimation were 74.5:1, 71.0:1, 59.0:0, 17.3:1, 53.0:0, 64.0:0, 47.0:1 and 56.0:0, respectively, which was highly significantly female biased and with no significant difference due to temperature or photoperiod. Offspring virgin females oviposited and induced the bump-shaped galls on plants under the same conditions as described above. Constant temperature, photoperiod and their interaction, and cold and thermal acclimation had no significant effect on the infestation rates ofEucalyptusbranches induced by offspring virgin females. Thus, temperature, photoperiod and cold and thermal acclimation did not influence female-biased sex ratio and tactics with thelytokous reproduction of offspring females inL. invasa.
Vom Paintball gezeichnet
Authors: Sandner Daniel , Bundi Beat , Müller Dominik , Müller Markus K. , Kistler Andreas D.
Published: July 2018

Zusammenfassung. Wir berichten über einen 29-jährigen Patienten, der via Ambulanz mit starken Bauchschmerzen auf der Notfallstation vorgestellt wurde. Nach initial unauffälliger Anamnese und Labor eröffnete erst die erneute Anamnese den Weg zur Diagnose: Ein Paintball-Geschoss hatte Folgen hinterlassen. Der Patient erlitt eine zweizeitige Milzruptur Grad III, die sich erst zwei Wochen nach dem Trauma manifestierte. Es erfolgte eine erfolgreiche organerhaltende, nicht-operative Therapie.
Perspektiven für das Elektroenzephalogramm in der Psychiatrie
Authors: Kirsten Alexandra , Linder Stefan , Olbrich Sebastian
Published: July 2018

Zusammenfassung. Das Elektroenzephalogramm (EEG) bietet eine non-invasive und kostengünstige Methode zur elektrophysiologischen Erfassung neuronaler Aktivität. Die im EEG nachweisbaren Pathologien erlauben mit hoher Sensitivität, aber begrenzter Spezifität einen Rückschluss auf einen abnormen Funktionszustand des Gehirns. Psychiatrische Hauptindikationen des EEGs stellen eine atypische klinische Präsentation eines neuropsychiatrischen Syndroms, die untypische Reaktion auf eine Medikation und die Basisdiagnostik vor Beginn einiger Medikamente bzw. Stimulationsverfahren dar. In der aktuellen Forschung hat das EEG nicht nur im Hinblick auf Diagnostik, sondern vor allem auf die Vorhersage des Behandlungserfolges verschiedener therapeutischer Ansätze Aufmerksamkeit auf sich gezogen. Der folgende Artikel behandelt unter anderem Elektrophysiologische Grundlagen des EEGs, EEG-gestützte Differenzialdiagnostik verschiedener Krankheitsbilder und neue Forschungsansätze in Diagnostik und Therapieplanung.
Der Einfluss von Protein auf die Prävention von Fragilitätsfrakturen bei älteren Erwachsenen
Authors: Lanz Patricia , Bischoff-Ferrari Heike A.
Published: July 2018

Zusammenfassung. Mit diesem Übersichtsartikel soll die Proteinzufuhr bei älteren Menschen mit einem Risiko für Fragilitätsfrakturen als ein modifizierbarer Faktor zur Frakturprävention diskutiert werden. Proteine sind Bausteine der Knochenmatrix und der Muskulatur. Diese Doppelfunktion passt zum Konzept der Prävention von Fragilitätsfrakturen bei älteren Menschen, die sowohl auf eine Reduktion des Knochenabbaus als auch auf die Sturzprävention abzielt. Bei älteren Menschen könnte eine proteinreiche Ernährung, neben den etablierten Empfehlungen zur ausreichenden Vitamin-D- und Kalzium-Zufuhr, eine weitere einfache und effiziente Massnahme zur Förderung der Knochen- und Muskelgesundheit darstellen.
Solar Particle Event Dose Forecasting Using Regression Techniques
Authors: Lovelace Alan Mitchel , Rashid Al Maqsudur , de Wet Wouter C. , Townsend Lawrence W. , Wesley Hines J. , Moussa Hanna
Published: July 2018

Doses from solar particle events can be a serious threat to the wellbeing of crews traveling through space. Therefore, methods for predicting the time such events will take place, methods for forecasting the dose buildup over time, and methods for forecasting the potential total dose from such events are needed to enable crews to take actions to mitigate the effects by entering a shielded area designed for their protection. This work focuses on forecasting the total dose expected for an event, based upon doses obtained very early in the event, using the kernel regression method. The model uses tables of calculated doses for historical solar particle events augmented with hypothetical events similar to the actual ones for training purposes. Reasonably accurate predictions of the total dose expected for an event can be made within the first hour after event onset. Predictive accuracies generally increase as the event progresses in time. The only inputs required are doses and times since event onset as provided by dosimetry devices. One hundred thirteen actual events with total doses between 1 and 1,000 cGy were tested using the model. At 1 hr into the event, total dose predictions were within ±30% of the actual total doses for 91 events (81%) and within ±15% for 54 of them (48%). Within the first 4 hr following event onset, total dose predictions were within ±30% for 98 events (87%) and within ±15% for 66 of them (58%). A software package implementing the model has been provided to the Space Radiation Analysis Group at NASA Johnson Space for incorporation into their operational procedures for analyzing possible threats to space crews from solar particle events.
Simulated Interannual Teleconnection Between the Summer North Atlantic Oscillation and Summer Precipitation in Eastern China During the Last Millennium
Authors: Peng Youbing
Published: July 2018

The interannual teleconnections between the summer North Atlantic Oscillation and summer precipitation in eastern China over the last millennium are investigated in a 1,000‐year simulation by the global climate model Community Climate System Model version 2.0.1. The model was able to roughly produce the general features of the teleconnection influences in eastern China, with negative (positive) precipitation anomalies north of 30°N and positive (negative) precipitation anomalies south of 30°N, associated with the positive (negative) phase of the North Atlantic Oscillation. The composite analysis reveals that the influence of the North Atlantic Oscillation on precipitation in summer in eastern China is chiefly via the “North Atlantic‐Eurasian teleconnection pattern,” which extends from the subtropical North Atlantic to East Asia.
Stress Concentrations in Weak Snowpack Layers and Conditions for Slab Avalanche Release
Authors: Gaume J. , Chambon G. , Herwijnen A. van , Schweizer J.
Published: July 2018

Dry‐snow slab avalanches release due to the formation of a crack in a weak layer buried below cohesive snow slabs, followed by rapid crack propagation. The onset of rapid crack propagation occurs if stresses at the crack tip in the weak layer overcome its strength. In this study, we use the finite element method to evaluate the maximum shear stress τmax induced by a preexisting crack in a weak snow layer allowing for the bending of the overlaying slab. It is shown that τmax increases with increasing crack length, slab thickness, slab density, weak layer elastic modulus, and slope angle. In contrast, τmax decreases with increasing elastic modulus of the slab. Assuming a realistic failure envelope, we computed the critical crack length ac for the onset of crack propagation. The model allows for remote triggering from flat (or low angle) terrain. Yet it shows that the critical crack length decreases with increasing slope angle.
An Empirical Dayglow Model for the Lyman‐Birge‐Hopfield‐Long Band Derived From the Polar Ultraviolet Imager Data
Authors: Wang Lingmin , Luan Xiaoli , Lei Jiuhou , Dou Xiankang
Published: July 2018

The Lyman‐Birge‐Hopfield‐long band dayglow emissions near 1,700 Å, which were observed by the ultraviolet imager on board Polar satellite, are characterized as a cosine‐like function of the solar zenith angle. These emissions are mainly excited by the solar extreme ultraviolet produced photoelectrons acting on the nitrogen molecules. The amplitude and phase factors are used to quantify the cosine‐like function and subsequently develop a dayglow model. In this study, a model is developed by considering broader dayglow emission areas outside the auroral oval, as the dayglow intensities in the dayside can exceed the auroral brightness, especially in summer. Also, this model is constructed by considering the seasonal variations of the two factors. It is demonstrated that, besides the strong solar cycle and universal time dependencies, the amplitude factors of the cosine‐like function show prominent seasonal variations, which are associated with the solar zenith angle changes. The amplitude factors are the largest in summer and smallest in winter. In addition, the dayglow phase factors show nearly constant values within each season, but throughout the year, they are higher in summer and equinoctial months and lower in winter. The dayglow model can benefit the investigation of global auroral patterns for all seasons.
Shaped 3D microcarriers for adherent cell culture and analysis
Authors: Wu Chueh-Yu , Stoecklein Daniel , Kommajosula Aditya , Lin Jonathan , Owsley Keegan , Ganapathysubramanian Baskar , Di Carlo Dino
Published: July 2018

Standard tissue culture of adherent cells is known to poorly replicate physiology and often entails suspending cells in solution for analysis and sorting, which modulates protein expression and eliminates intercellular connections. To allow adherent culture and processing in flow, we present 3D-shaped hydrogel cell microcarriers, which are designed with a recessed nook in a first dimension to provide a tunable shear-stress shelter for cell growth, and a dumbbell shape in an orthogonal direction to allow for self-alignment in a confined flow, important for processing in flow and imaging flow cytometry. We designed a method to rapidly design, using the genetic algorithm, and manufacture the microcarriers at scale using a transient liquid molding optofluidic approach. The ability to precisely engineer the microcarriers solves fundamental challenges with shear-stress-induced cell damage during liquid-handling, and is poised to enable adherent cell culture, in-flow analysis, and sorting in a single format.
Genetic correlation network prediction of forest soil microbial functional organization
Authors: Ma Bin , Zhao Kankan , Lv Xiaofei , Su Weiqin , Dai Zhongmin , Gilbert Jack A , Brookes Philip C , Faust Karoline , Xu Jianming
Published: July 2018

Soil ecological functions are largely determined by the activities of soil microorganisms, which, in turn, are regulated by relevant interactions between genes and their corresponding pathways. Therefore, the genetic network can theoretically elucidate the functional organization that supports complex microbial community functions, although this has not been previously attempted. We generated a genetic correlation network based on 5421 genes derived from metagenomes of forest soils, identifying 7191 positive and 123 negative correlation relationships. This network consisted of 27 clusters enriched with sets of genes within specific functions, represented with corresponding cluster hubs. The clusters revealed a hierarchical architecture, reflecting the functional organization in the soil metagenomes. Positive correlations mapped functional associations, whereas negative correlations often mapped regulatory processes. The potential functions of uncharacterized genes were predicted based on the functions of located clusters. The global genetic correlation network highlights the functional organization in soil metagenomes and provides a resource for predicting gene functions. We anticipate that the genetic correlation network may be exploited to comprehensively decipher soil microbial community functions.
Manic Fringe deficiency imposes Jagged1 addiction to intestinal tumor cells
Authors: López-Arribillaga Erika , Rodilla Verónica , Colomer Carlota , Vert Anna , Shelton Amy , Cheng Jason H. , Yan Bing , Gonzalez-Perez Abel , Junttila Melissa R. , Iglesias Mar , Torres Ferran , Albanell Joan , Villanueva Alberto , Bigas Anna , Siebel Christian W. , Espinosa LLuís
Published: July 2018

Delta ligands regulate Notch signaling in normal intestinal stem cells, while Jagged1 activates Notch in intestinal adenomas carrying active β-catenin. We used the ApcMin/+ mouse model, tumor spheroid cultures, and patient-derived orthoxenografts to address this divergent ligand-dependent Notch function and its implication in disease. We found that intestinal-specific Jag1 deletion or antibody targeting Jag1 prevents tumor initiation in mice. Addiction to Jag1 is concomitant with the absence of Manic Fringe (MFNG) in adenoma cells, and its ectopic expression reverts Jag1 dependence. In 239 human colorectal cancer patient samples, MFNG imposes a negative correlation between Jag1 and Notch, being high Jag1 in the absence of MFNG predictive of poor prognosis. Jag1 antibody treatment reduces patient-derived tumor orthoxenograft growth without affecting normal intestinal mucosa. Our data provide an explanation to Jag1 dependence in cancer, and reveal that Jag1–Notch1 interference provides therapeutic benefit in a subset of colorectal cancer and FAP syndrome patients.
New insights into the design of conjugated polymers for intramolecular singlet fission
Authors: Hu Jiahua , Xu Ke , Shen Lei , Wu Qin , He Guiying , Wang Jie-Yu , Pei Jian , Xia Jianlong , Sfeir Matthew Y.
Published: July 2018

Singlet fission (SF), a multiple exciton generation process that generates two triplet excitons after the absorption of one photon, can potentially enable more efficient solar cell designs by harvesting energy normally lost as heat. While low-bandgap conjugated polymers are highly promising candidates for efficient SF-based solar cells, few polymer materials capable of SF have been reported because the SF process in polymer chains is poorly understood. Using transient spectroscopy, we demonstrate a new, highly efficient (triplet yield of 160–200%) isoindigo-based donor–acceptor polymer and show that the triplet pairs are directly emissive and exhibit a time-dependent energy evolution. Importantly, aggregation in poor solvents and in films significantly lowers the singlet energy, suppressing triplet formation because the energy conservation criterion is no longer met. These results suggest a new design rule for developing intramolecular SF capable low-bandgap conjugated polymers, whereby inter-chain interactions must be carefully engineered.
Fast Maximum Likelihood Estimation via Equilibrium Expectation for Large Network Data
Authors: Byshkin Maksym , Stivala Alex , Mira Antonietta , Robins Garry , Lomi Alessandro
Published: July 2018

A major line of contemporary research on complex networks is based on the development of statistical models that specify the local motifs associated with macro-structural properties observed in actual networks. This statistical approach becomes increasingly problematic as network size increases. In the context of current research on efficient estimation of models for large network data sets, we propose a fast algorithm for maximum likelihood estimation (MLE) that affords a significant increase in the size of networks amenable to direct empirical analysis. The algorithm we propose in this paper relies on properties of Markov chains at equilibrium, and for this reason it is called equilibrium expectation (EE). We demonstrate the performance of the EE algorithm in the context of exponential random graph models (ERGMs) a family of statistical models commonly used in empirical research based on network data observed at a single period in time. Thus far, the lack of efficient computational strategies has limited the empirical scope of ERGMs to relatively small networks with a few thousand nodes. The approach we propose allows a dramatic increase in the size of networks that may be analyzed using ERGMs. This is illustrated in an analysis of several biological networks and one social network with 104,103 nodes.
High Dose Vitamin D supplementation alters faecal microbiome and predisposes mice to more severe colitis
Authors: Ghaly Simon , Kaakoush Nadeem O. , Lloyd Frances , McGonigle Terence , Mok Danny , Baird Angela , Klopcic Borut , Gordon Lavinia , Gorman Shelley , Forest Cynthia , Bouillon Roger , Lawrance Ian C. , Hart Prue H.
Published: July 2018

Vitamin D has been suggested as a possible adjunctive treatment to ameliorate disease severity in human inflammatory bowel disease. In this study, the effects of diets containing high (D++, 10,000 IU/kg), moderate (D+, 2,280 IU/kg) or no vitamin D (D−) on the severity of dextran sodium sulphate (DSS) colitis in female C57Bl/6 mice were investigated. The group on high dose vitamin D (D++) developed the most severe colitis as measured by blinded endoscopic (p < 0.001) and histologic (p < 0.05) assessment, weight loss (p < 0.001), drop in serum albumin (p = 0.05) and increased expression of colonic TNF-α (p < 0.05). Microbiota analysis of faecal DNA showed that the microbial composition of D++ control mice was more similar to that of DSS mice. Serum 25(OH)D3 levels reduced by 63% in the D++ group and 23% in the D+ group after 6 days of DSS treatment. Thus, high dose vitamin D supplementation is associated with a shift to a more inflammatory faecal microbiome and increased susceptibility to colitis, with a fall in circulating vitamin D occurring as a secondary event in response to the inflammatory process.
Novel application of In Vivo Micro-Optical Coherence Tomography to assess Cornea scarring in an Animal Model
Authors: Ang Marcus , Devarajan Kavya , Das Suchandrima , Yam Gary H. F. , Htoon Hla Mynt , Chen Si , Liu Xinyu , Liu Linbo , Girard Michael , Mehta Jodhbir S.
Published: July 2018

This pilot study uses a micro-optical coherence tomography (micro-OCT) system with ~1 μm axial resolution specifically to image the cornea and corneal scars in vivo. We used an established murine corneal scar model by irregular phototherapeutic keratectomy in ten C57BL/6 mice, with serial imaging using the micro-OCT and compared to anterior segment (AS-OCT) (RTvue, Optovue, Fremont, CA) before and after scar induction. Main outcome was agreement between the AS-OCT and micro-OCT using Bland-Altman plots (95% limits of agreement, LoA).We analysed 10 control eyes and 10 eyes with corneal scars and found that there was good agreement between AS-OCT and micro-OCT (P > 0.05) LOA: lower limit −14 µm (95% CI: −19 to −8.8 µm) upper limit 23 µm (95% CI: 18 to 28.5 µm) in terms of central corneal thickness. There was also good agreement between AS-OCT and micro-OCT in terms of corneal scar measurements (P > 0.5; correlation coefficient >0.99) LOA lower limit −2.1 µm (95% CI: −2.8 to −1.5 µm); upper limit 1.8 µm (95% CI: 1.1 to 2.4 µm). Our pilot study suggests that this novel in vivo micro-OCT imaging technique was able to measure central corneal thickness and scar thickness in agreement with current AS-OCT techniques.
A convex 3D deconvolution algorithm for low photon count fluorescence imaging
Authors: Ikoma Hayato , Broxton Michael , Kudo Takamasa , Wetzstein Gordon
Published: July 2018

Deconvolution is widely used to improve the contrast and clarity of a 3D focal stack collected using a fluorescence microscope. But despite being extensively studied, deconvolution algorithms can introduce reconstruction artifacts when their underlying noise models or priors are violated, such as when imaging biological specimens at extremely low light levels. In this paper we propose a deconvolution method specifically designed for 3D fluorescence imaging of biological samples in the low-light regime. Our method utilizes a mixed Poisson-Gaussian model of photon shot noise and camera read noise, which are both present in low light imaging. We formulate a convex loss function and solve the resulting optimization problem using the alternating direction method of multipliers algorithm. Among several possible regularization strategies, we show that a Hessian-based regularizer is most effective for describing locally smooth features present in biological specimens. Our algorithm also estimates noise parameters on-the-fly, thereby eliminating a manual calibration step required by most deconvolution software. We demonstrate our algorithm on simulated images and experimentally-captured images with peak intensities of tens of photoelectrons per voxel. We also demonstrate its performance for live cell imaging, showing its applicability as a tool for biological research.
Modelling extreme desiccation tolerance in a marine tardigrade
Authors: Sørensen-Hygum Thomas L. , Stuart Robyn M. , Jørgensen Aslak , Møbjerg Nadja
Published: July 2018

It has recently been argued that the enigmatic tardigrades (water bears) will endure until the sun dies, surviving any astrophysical calamities in Earth’s oceans. Yet, our knowledge of stress tolerance among marine tardigrade species is very limited and most investigations revolve around species living in moist habitats on land. Here, we investigate desiccation tolerance in the cosmopolitan marine tidal tardigrade, Echiniscoides sigismundi, providing the first thorough analysis on recovery upon desiccation from seawater. We test the influence on survival of desiccation surface, time spent desiccated (up to 1 year) and initial water volume. We propose analysis methods for survival estimates, which can be used as a future platform for evaluating and analysing recovery rates in organisms subjected to extreme stress. Our data reveal that marine tidal tardigrades tolerate extremely rapid and extended periods of desiccation from seawater supporting the argument that these animals are among the toughest organisms on Earth.
The transcriptional factor ZEB1 represses Syndecan 1 expression in prostate cancer
Authors: Farfán Nancy , Ocarez Nallatt , Castellón Enrique A. , Mejía Nilo , de Herreros Antonio García , Contreras Héctor R.
Published: July 2018

Syndecan 1 (SDC-1) is a cell surface proteoglycan with a significant role in cell adhesion, maintaining epithelial integrity. SDC1 expression is inversely related to aggressiveness in prostate cancer (PCa). During epithelial to mesenchymal transition (EMT), loss of epithelial markers is mediated by transcriptional repressors such as SNAIL, SLUG, or ZEB1/2 that bind to E-box promoter sequences of specific genes. The effect of these repressors on SDC-1 expression remains unknown. Here, we demonstrated that SNAIL, SLUG and ZEB1 expressions are increased in advanced PCa, contrarily to SDC-1. SNAIL, SLUG and ZEB1 also showed an inversion to SDC-1 in prostate cell lines. ZEB1, but not SNAIL or SLUG, represses SDC-1 as demonstrated by experiments of ectopic expression in epithelial prostate cell lines. Inversely, expression of ZEB1 shRNA in PCa cell line increased SDC-1 expression. The effect of ZEB1 is transcriptional since ectopic expression of this gene represses SDC-1 promoter activity and ZEB1 binds to the SDC-1 promoter as detected by ChIP assays. An epigenetic mark associated to transcription repression H3K27me3 was bound to the same sites that ZEB1. In conclusion, this study identifies ZEB1 as a key repressor of SDC-1 during PCa progression and point to ZEB1 as a potentially diagnostic marker for PCa.
The reciprocal interplay between TNFα and the circadian clock impacts on cell proliferation and migration in Hodgkin lymphoma cells
Authors: Abreu Mónica , Basti Alireza , Genov Nikolai , Mazzoccoli Gianluigi , Relógio Angela
Published: July 2018

A bidirectional interaction between the circadian network and effector mechanisms of immunity brings on a proper working of both systems. In the present study, we used Hodgkin lymphoma (HL) as an experimental model for a type of cancer involving cells of the immune system. We identified this cancer type among haematological malignancies has having a strong differential expression of core-clock elements. Taking advantage of bioinformatics analyses and experimental procedures carried out in III- and IV-stage HL cells, and lymphoblastoid B cells, we explored this interplay and bear out diverse interacting partners of both systems. In particular, we assembled a wide-ranging network of clock-immune-related genes and pinpointed TNF as a crucial intermediary player. A robust circadian clock hallmarked III-stage lymphoma cells, differently from IV-stage HL cells, which do not harbour a properly functioning clockwork. TNF and circadian gene modulation impacted on clock genes expression and triggered phenotypic changes in lymphoma cells, suggesting a crucial involvement of core-clock elements and TNF in the physiopathological mechanisms hastening malignancy. Our results move forward our understanding of the putative role of the core-clock and TNF in the pathobiology of Hodgkin lymphoma, and highlight their influence in cellular proliferation and migration in lymphatic cancers.
Tissue-specific Network Analysis of Genetic Variants Associated with Coronary Artery Disease
Authors: Miao Xiao , Chen Xinlin , Xie Zhijun , Lin Honghuang
Published: July 2018

Coronary artery disease (CAD) is a leading cause of death worldwide. Recent genome-wide association studies have identified more than one hundred susceptibility loci associated with CAD. However, the underlying mechanism of these genetic loci to CAD susceptibility is still largely unknown. We performed a tissue-specific network analysis of CAD using the summary statistics from one of the largest genome-wide association studies. Variant-level associations were summarized into gene-level associations, and a CAD-related interaction network was built using experimentally validated gene interactions and gene coexpression in coronary artery. The network contained 102 genes, of which 53 were significantly associated with CAD. Pathway enrichment analysis revealed that many genes in the network were involved in the regulation of peripheral arteries. In summary, we performed a tissue-specific network analysis and found abnormalities in the peripheral arteries might be an important pathway underlying the pathogenesis of CAD. Future functional characterization might further validate our findings and identify potential therapeutic targets for CAD.
Development of a versatile analytical protocol for the comprehensive determination of the elemental composition of smartphone compartments on the example of printed circuit boards
Authors: Bookhagen B. , Obermaier W. , Opper C. , Koeberl C. , Hofmann T. , Prohaska T. , Irrgeher J.
Published: July 2018

A comprehensive method for the determination of metals in electronic devices was developed and tested on smartphones.
An ethyl cyanoacetate based turn-on fluorescent probe for hydrazine and its bio-imaging and environmental applications
Authors: Li Zihong , Ren Mingguang , Wang Li , Lin Weiying
Published: July 2018

A new probe N-N2H4 was synthesized with ethyl cyanoacetate as the recognition site for detecting hydrazine (N2H4). The probe is expected to be employed to detect N2H4 in biosamples and environmental pollution.
Extremely stable europium-organic framework for luminescent sensing of Cr2O72− and Fe3+ in aqueous systems
Authors: Gai Yan-Li , Guo Qin , Zhao Xue-Yan , Chen Yan , Liu Shan , Zhang Yuan , Zhuo Chun-Xue , Yao Cui , Xiong Ke-Cai
Published: July 2018

A novel Eu-MOF which is extremely stable in an aqueous system over a wide pH range is reported as a dual functional Cr2O72− and Fe3+ sensor in aqueous environments.
A dual response fluorescent sensor for HNO and S2−ions using a Cu(ii) complex based probe assisted by detailed DFT studies
Authors: Dutta Ananya , Alam Rabiul , Islam Abu Saleh Musha , Dutta Arpan , Ali Mahammad
Published: July 2018

A Cu(ii) based sensor for selective detection of HNO and S2−with detailed DFT studies is reported here.
A silver catalyzed domino reaction of N-cyanamide alkenes and 1,3-dicarbonyls for the synthesis of quinazolinones
Authors: Xu Gang , Tong Chaodi , Cui Sunliang , Dai Liyan
Published: July 2018

A silver catalyzed domino reaction of N-cyanamide alkenes and 1,3-dicarbonyls has been developed for the facile synthesis of quinazolinones.
Copper-catalyzed generation of flavone selenide and thioether derivatives using KSeCN and KSCN via C–H functionalization
Authors: Zhu Jie , Xu Baojun , Yu Jingjing , Ren Yaokun , Wang Jin , Xie Ping , Pittman Charles U. , Zhou Aihua
Published: July 2018

Two simple Cu-catalyzed methods using KSeCN and KSCN to construct C–Se and C–S bonds on flavone skeletal structures via C–H functionalization are developed.
Proton coupled electron transfer from Co3O4 nanoparticles to photogenerated Ru(bpy)33+: base catalysis and buffer effect
Authors: Volpato Giulia Alice , Bonetto Alessandro , Marcomini Antonio , Mialane Pierre , Bonchio Marcella , Natali Mirco , Sartorel Andrea
Published: July 2018

Flash photolysis studies indicate general base catalysis by borate in photoinduced proton-coupled electron transfer from Co3O4 nanoparticles to Ru(iii)(bpy)33+.
Formation of three-dimensional colloidal crystals in a nematic liquid crystal
Authors: Wang Yiwei , Zhang Pingwen , Chen Jeff Z. Y.
Published: July 2018

The overall three-dimensional crystal structures, formed by spherical colloids and liquid crystal molecules in the voids, are influenced by the size and the position of colloidal particles.
A one building block approach for defect-enhanced conjugated microporous polymers: defect utilization for recyclable and catalytic biomass conversion
Authors: Cho Kyoungil , Lee Sang Moon , Kim Hae Jin , Ko Yoon-Joo , Son Seung Uk
Published: July 2018

A one building block approach for conjugated microporous polymers resulted in enhanced defects which were utilized for the development of solid acid catalysts.
Localized cancer treatment by radio-frequency hyperthermia using magnetic nanoparticles immobilized on graphene oxide: from novel synthesis to in vitro studies
Authors: Kumar Ravi , Chauhan Anjali , Jha Sushil K. , Kuanr Bijoy Kumar
Published: July 2018

Innovative, theranostic hybrid nanocomposite of graphene oxide and iron oxide for radio-frequency hyperthermia therapy.
Near-infrared light triggered drug release from mesoporous silica nanoparticles
Authors: Zhao Tiancong , Chen Liang , Li Qin , Li Xiaomin
Published: July 2018

Stimuli triggered drug delivery systems enable controlled release of drugs at the optimal space and time, thus achieving optimal therapeutic effects.
Hierarchically porous carbons with controlled structures for efficient microwave absorption
Authors: Wu Zhengchen , Hu Wei , Huang Ting , Lan Ping , Tian Ke , Xie Feifie , Li Lei
Published: July 2018

The influence of hierarchically porous structures on their microwave absorption performance is investigated thoroughly.
Influence of growth kinetics on Sn incorporation in direct band gap Ge1−xSnx nanowires
Authors: Doherty Jessica , Biswas Subhajit , Saladukha Dzianis , Ramasse Quentin , Bhattacharya Tara Shankar , Singha Achintya , Ochalski Tomasz J. , Holmes Justin D.
Published: July 2018

An investigation of the influence of growth kinetics on Sn incorporation in Ge1−xSnx nanowires.
Modelling mid-infrared molecular emission lines from T Tauri stars
Authors: Woitke P. , Min M. , Thi W.-F. , Roberts C. , Carmona A. , Kamp I. , Ménard F. , Pinte C.
Published: July 2018

We introduce a new modelling framework including the Fast Line Tracer (FLITS) to simulate infrared line emission spectra from protoplanetary discs. This paper focusses on the mid-IR spectral region between 9.7 and 40 μm for T Tauri stars. The generated spectra contain several tens of thousands of molecular emission lines of H2O, OH, CO, CO2, HCN, C2H2, H2, and a few other molecules, as well as the forbidden atomic emission lines of S I, S II, S III, Si II, Fe II, Ne II, Ne III, Ar II, and Ar III. In contrast to previously published works, we do not treat the abundances of the molecules nor the temperature in the disc as free parameters, but use the complex results of detailed 2D PRODIMO disc models concerning gas and dust temperature structure, and molecular concentrations. FLITS computes the line emission spectra by ray tracing in an efficient, fast, and reliable way. The results are broadly consistent with R = 600 Spitzer/IRS observational data of T Tauri stars concerning line strengths, colour, and line ratios. In order to achieve that agreement, however, we need to assume either a high gas/dust mass ratio of order 1000, or the presence of illuminated disc walls at distances of a few au, for example, due to disc–planet interactions. These walls are irradiated and heated by the star which causes the molecules to emit strongly in the mid-IR. The molecules in the walls cannot be photodissociated easily by UV because of the large densities in the walls favouring their re-formation. Most observable molecular emission lines are found to be optically thick. An abundance analysis is hence not straightforward, and the results of simple slab models concerning molecular column densities can be misleading. We find that the difference between gas and dust temperatures in the disc surface is important for the line formation. The mid-IR emission features of different molecules probe the gas temperature at different depths in the disc, along the following sequence: OH (highest)–CO–H2O and CO2–HCN–C2H2 (deepest), just where these molecules start to become abundant. We briefly discuss the effects of C/O ratio and choice of chemical rate network on these results. Our analysis offers new ways to infer the chemical and temperature structure of T Tauri discs from future James Webb Space Telescope (JWST)/MIRI observations, and to possibly detect secondary illuminated disc walls based on their specific mid-IR molecular signature.
Detection of 25 new rotating radio transients at 111 MHz
Authors: Tyul’bashev S. A. , Tyul’bashev V. S. , Malofeev V. M.
Published: July 2018

Nearly all fast rotating radio transients (RRAT) that are pulsars with rare pulses have previously been detected using decimeter wavelengths. We present here 34 transients detected at meter wavelengths in our daily monitoring at declinations −9° ≤ δ ≤ +42°. Twenty-five transients are new RRATs. We confirm the detection of 7 RRATs based on our early observations. One of the 34 detected transients was determined to be a new pulsar, J1326+3346. At the same time, of the 35 RRATs detected at the decimeter wavelengths in the studied area, only one was detected by us, J1848+1518. The periods of 6 RRATs were found from the arrival time of single pulses. Three quarters of all RRATs were observed more than once, and the total number of RRATs in the area we studied has doubled.