bluuebunny/crossref_metadata_2025 huggingface dataset:
Coordinating of thermal and dielectric properties for cyanate ester composites filled with silica‐coated sulfonated graphene oxide hybrids
Authors: Ni Rongfeng , Chen Qian , Ding Xifeng
Published: June 2017

The cyanate ester (CE) resin is widely used for electrical and electronics packaging due to its excellent dielectric properties, high heat resistance and low water absorption. However, the low thermal conductivity limits its application in highly integrated circuits. In this work, cyanate ester (CE) based composites filled with silicon dioxide (SiO2) coated sulfonated graphene oxide (SGO) were successfully prepared by sol‐gel process to coordinate its thermal conductivity and dielectric properties. The obtained composites showed enhanced thermal conductivity and maintained good insulating properties. It was found that the thermal conductivity of the composites increased with the loading of SiO2@SGO hybrids and reached a maximum of 0.71 W·m−1·K−1 with 25 wt% fillers, 3.4 times higher than the baseline CE resin. This increase is attributed to the presence of SiO2@SGO, which improved the phonon transmission channel in CE resin, and the surface modification on SGO also reduced interfacial thermal resistance between SiO2@SGO and CE resin. The thermal stability of the composites has been improved from about 300°C to 390°C. Furthermore, the prepared SiO2@SGO/CE composites exhibited excellent dielectric performance for electronics packaging applications. POLYM. COMPOS., 39:E1565–E1573, 2018. © 2017 Society of Plastics Engineers
Pyrophosphate‐Imprinted Magnetic Mesoporous Silica Microspheres for Recognition, Enrichment and MS Detection of Phosphopeptides
Authors: Lv Nan , Zhang Jilin , Li Guangming , Wang Xun , Ni Jiazuan
Published: June 2017

Protein phosphorylation is one of the most important post‐translational modifications involved in the regulation of various cellular processes. Selective capture of phosphopeptides from complex biological samples is essential prior to mass spectrometry (MS) analysis of protein phosphorylation. Herein, pyrophosphate‐imprinted magnetic affinity microspheres composed of a magnetic Fe3O4 core and pyrophosphate‐imprinted mesoporous silica shell have been facilely synthesized through the combination of a surfactant‐templated sol–gel process and a dual‐template docking oriented molecular imprinting process. They have a relatively large specific surface area (142.1 m2 g−1) and superparamagnetism with a saturation magnetization (Ms) value (66.54 emu g−1). In virtue of their selective affinity with molecular recognition, porous structure and strong magnetism, they can realize the rapid and effective purification of phosphopeptides from real biosamples for MS analysis. These results reveal that this work will be beneficial for future applications in the fast magnetic isolation and specific identification of phosphorylated biomolecules.
ESP‐Promoted Suzuki‐Miyaura Cross‐Coupling and Peptide Bond Formation Reactions in Water at Room Temperature
Authors: Konwar Manashjyoti , Boruah Preeti Rekha , Saikia Prakash J. , Khupse Nageshewar D. , Sarma Diganta
Published: June 2017

A potential green protocol for C−C and C−N bond formation reactions in aqueous medium promoted by basic waste biomass has been developed. The protocol involves the use of Egg Shell Powder (ESP) in water as a green heterogeneous reaction media which is basic in nature and offers a mild, resourceful and inexpensive alternative to the conventional protocols for palladium catalyzed C−C (Suzuki‐Miyaura) and C−N (Peptide coupling) bond formation reactions. The reactions proceeded in basic ESP medium in air at short reaction time at room temperature under ‘external base/external promoter/ligand/organic solvent’ free conditions.
Genome‐scale metabolic models applied to human health and disease
Authors: Cook Daniel J , Nielsen Jens
Published: June 2017

Advances in genome sequencing, high throughput measurement of gene and protein expression levels, data accessibility, and computational power have allowed genome‐scale metabolic models (GEMs) to become a useful tool for understanding metabolic alterations associated with many different diseases. Despite the proven utility of GEMs, researchers confront multiple challenges in the use of GEMs, their application to human health and disease, and their construction and simulation in an organ‐specific and disease‐specific manner. Several approaches that researchers are taking to address these challenges include using proteomic and transcriptomic‐informed methods to build GEMs for individual organs, diseases, and patients and using constraints on model behavior during simulation to match observed metabolic fluxes. We review the challenges facing researchers in the use of GEMs, review the approaches used to address these challenges, and describe advances that are on the horizon and could lead to a better understanding of human metabolism. WIREs Syst Biol Med 2017, 9:e1393. doi: 10.1002/wsbm.1393

This article is categorized under:

Analytical and Computational Methods > Computational Methods

Biological Mechanisms > Metabolism

Models of Systems Properties and Processes > Organ, Tissue, and Physiological Models
Kuwait bone marrow transplantation activities
Authors: Al Shemmari Salem H. , Ameen Reem
Published: June 2017

Kuwait is located in the Arabian Gulf and has a population of 3.5 million. The stem cell transplantation program started in 2000. Autologous peripheral blood stem cell transplantation started first, as it was easier technically to establish. In 2011, the allogeneic program started with focus on acute leukemia and hemoglobinopathies. The success of both programs required teamwork and support of health planners. The Kuwait National Bone Marrow Registry was established in 2012. The issue of donor availability and drug shortage remain the two main obstacles for expanding the bone marrow transplantation program.
Consumption of antibiotics by children in Greece
Authors: Maltezou Helena C. , Dedoukou Xanthi , Asimaki Hara , Kontou Ioanna , Ioannidou Loukia , Mitromara Konstantina , Theodoridou Kalliopi , Katerelos Panos , Theodoridou Maria
Published: June 2017

Background:

Greece is among the European countries with the highest consumption of antibiotics.

Objectives:

To study the rates and characteristics of consumption of antibiotics in the community by children in Greece.

Methods:

Questionnaire-based study of parents of hospitalized children.

Results:

A total of 549 children were studied; 247 (45%) received at least one course of antibiotics the previous year (mean number of antibiotic courses the past year: 1.9), including 427 (91.8%) following examination by a pediatrician, 6 (1.3%) following phone consultation, 2 (0.4%) following suggestion by a pharmacist and 2 (0.4%) as self-medication. Prevalent reasons for antibiotic consumption were acute otitis media (AOM) (27.3%), pharyngotonsillitiss (25.4%), and bronchitis (17.8%). Amoxicillin-clavulanate was the prevalent antibiotic for pharyngotonsillitis, urinary tract infection (UTI) and skin infection (30.5%, 35.7% and 36.4% of cases, respectively), amoxicillin for AOM and pneumonia (32.3% and 36.4% of cases, respectively), and clarithromycin for bronchitis (27.7%). We found 84.3%, 81.9%, 64.3%, 63.7%, and 50% of parents reporting treatment consisted with the national guidelines for AOM, pneumonia, UTI, skin infection, and pharyngotonsillitis, respectively. In the multivariate analysis, an age of 1–5 years and asthma were significantly associated with a higher probability for antibiotic consumption.

Conclusions:

Antibiotic consumption of children in Greece is mainly driven by pediatricians. Continuing medical education is expected to further improve antibiotic prescription practices by pediatricians.
∊-constraint heat transfer search (∊-HTS) algorithm for solving multi-objective engineering design problems
Authors: Tawhid Mohamed A. , Savsani Vimal
Published: June 2017

In this paper, an effective ∊-constraint heat transfer search (∊-HTS) algorithm for the multi-objective engineering design problems is presented. This algorithm is developed to solve multi-objective optimization problems by evaluating a set of single objective sub-problems. The effectiveness of the proposed algorithm is checked by implementing it on multi-objective benchmark problems that have various characteristics of Pareto front such as discrete, convex, and non-convex. This algorithm is also tested for several distinctive multi-objective engineering design problems, such as four bar truss problem, gear train problem, multi-plate disc brake design, speed reducer problem, welded beam design, and spring design problem. Moreover, the numerical experimentation shows that the proposed algorithm generates the solution to represent true Pareto front.

Highlights A novel multi-objective optimization (MOO) algorithm is proposed. Proposed algorithm is presented to obtain the Pareto-optimal solutions. The multi-objective optimization algorithm compared with other work in the literature. Test performance of proposed algorithm on MOO benchmark/design engineering problems.
Access, Education and Policy Awareness: Predictors of Influenza Vaccine Acceptance Among VHA Healthcare Workers
Authors: Eaton Jennifer Lipkowitz , Mohr David C. , McPhaul Kathleen M. , Kaslow Richard A. , Martinello Richard A.
Published: June 2017

OBJECTIVE

To identify predictors of influenza vaccine acceptance among VHA healthcare workers (HCWs), with emphasis on modifiable factors related to promotion campaigns.

DESIGN

Survey.

SETTING

National single-payer healthcare system with 140 hospitals and 321,000 HCWs.

PARTICIPANTS

National voluntary sample of HCWs in the Veterans Health Administration (VHA) system.

METHODS

We invited a random sample of 5% of all VHA HCWs to participate. An 18-item intranet-based survey inquired about occupation, vaccination status, employer policy, and local campaign efforts.

RESULTS

The response rate was 17.4%. Of 2,502 initial respondents, 2,406 (96.2%) provided usable data. This sample includes respondents from all 140 VA hospitals. Self-reported influenza vaccination rates were highest among physicians (95.6%) and licensed independent providers (88.3%). Nonclinical staff (80.7%) reported vaccine uptake similar to other certified but nonlicensed providers (81.2%). The strongest predictor of vaccine acceptance among VHA HCWs was individual awareness of organizational policy. Vaccine acceptance was also higher among HCWs who reported more options for access to vaccination and among those in facilities with more education activities.

CONCLUSIONS

Influenza vaccine acceptance varied significantly by employee awareness of employer policy and on-site access to vaccine. Employer-sponsored activities to increase access continue to show positive returns across occupations. Local influenza campaign efforts to educate HCWs may have reached saturation in this target group. These results suggest that focused communications to increase HCW awareness and understanding of employer policy can drive further increase in influenza vaccination acceptance.

Infect Control Hosp Epidemiol 2017;38:970–975
President Obama's War Powers Legacy
Authors: Bradley Curtis A.
Published: June 2017

The five essays in this Agora, written by Jack Goldsmith and myself, Ashley Deeks, Ryan Goodman, Rebecca Ingber, and Michael Ramsey, consider the legal legacy of the Obama administration concerning the use of military force, with respect to both domestic law and international law. Prominent developments during the Obama administration relating to war powers include the administration's defense in habeas litigation of its authority to detain members of Al Qaeda and associated groups in military custody; its increased use of targeted killing outside of active combat areas, in part through frequent missile attacks carried out by drones; its use of military force in 2011 against the regime of Libyan leader Muammar Qaddafi, pursuant to a United Nations Security Council resolution; its deliberations in 2013 about the use of military force against Syria in response to the use of chemical weapons by the regime of Syrian President Bashar al-Assad; and its initiation of a long-term conflict against the Islamic State in 2014. This Agora touches on these and other developments and offers a range of perspectives.
RELATIVE PERFORMANCE OF BORON, SULPHUR AND ZINC COATINGS ONTO PRILLED UREA FOR INCREASING PRODUCTIVITY AND NITROGEN USE EFFICIENCY IN MAIZE
Authors: POONIYA VIJAY , SHIVAY YASHBIR SINGH , PAL MADAN , BANSAL RADHIKA
Published: June 2017

Deficiencies of micro (Zn, B) and secondary (S) nutrients are well-documented in soil as well as in cereal crops, leading to decreased crop yields and low nutritional quality of food. We evaluated the effects of coated urea on maize yield, N and Zn uptake, and input cost relationships. Field experiments were conducted on maize to test boron-coated (BCU), sulphur-coated (SCU) and zinc-coated urea (ZnCU) during 2013 and 2014. On the basis of 2 years’ average data, the highest grain yield was achieved with 0.5% BCU, 5% SCU and 2.5% ZnCU as zinc sulphate hepta hydrate. These treatments increased yields by 5.4, 12.8 and 9.9% over prilled urea (PU), respectively. Application of 0.5% BCU (supplying 1.4 kg B ha−1), 5% SCU (supplying 14.1 kg S ha−1) and 2.5% ZnCU (supplying 7.05 kg Zn ha−1) registered the highest N concentrations and uptake in grain and stover. Total N uptake (grain + stover) was increased by 7.6, 16.7 and 17.1% with BCU, SCU and ZnCU treatments over PU. As compared to PU, Zn concentration in maize grain was significantly higher and total Zn uptake (grain + stover) increased by 32.4% with 2.5% ZnCU. Coated urea materials also enhanced the partial factor productivity (PFPN), agronomic efficiency (AEN), recovery efficiency (REN) and harvest index (HIN) over those of PU. From the economic viewpoint this study suggests that coating of urea with 0.3% boron, 5% sulphur or 2% zinc gives maximum net returns and benefit-cost ratio. Our data indicate that coating of B, Zn and S onto urea increases maize yield, profitability and nitrogen use efficiency in the western Indo-Gangetic plains of India.
The impact of traumatic stress on Pavlovian biases
Authors: Ousdal O. T. , Huys Q. J. , Milde A. M. , Craven A. R. , Ersland L. , Endestad T. , Melinder A. , Hugdahl K. , Dolan R. J.
Published: June 2017

Background

Disturbances in Pavlovian valuation systems are reported to follow traumatic stress exposure. However, motivated decisions are also guided by instrumental mechanisms, but to date the effect of traumatic stress on these instrumental systems remain poorly investigated. Here, we examine whether a single episode of severe traumatic stress influences flexible instrumental decisions through an impact on a Pavlovian system.

Methods

Twenty-six survivors of the 2011 Norwegian terror attack and 30 matched control subjects performed an instrumental learning task in which Pavlovian and instrumental associations promoted congruent or conflicting responses. We used reinforcement learning models to infer how traumatic stress affected learning and decision-making. Based on the importance of dorsal anterior cingulate cortex (dACC) for cognitive control, we also investigated if individual concentrations of Glx (=glutamate + glutamine) in dACC predicted the Pavlovian bias of choice.

Results

Survivors of traumatic stress expressed a greater Pavlovian interference with instrumental action selection and had significantly lower levels of Glx in the dACC. Across subjects, the degree of Pavlovian interference was negatively associated with dACC Glx concentrations.

Conclusions

Experiencing traumatic stress appears to render instrumental decisions less flexible by increasing the susceptibility to Pavlovian influences. An observed association between prefrontal glutamatergic levels and this Pavlovian bias provides novel insight into the neurochemical basis of decision-making, and suggests a mechanism by which traumatic stress can impair flexible instrumental behaviours.
HOSPITAL-BASED HEALTH TECHNOLOGY ASSESSMENT IN BRAZIL: AN OVERVIEW OF THE INITIAL EXPERIENCES
Authors: Pereira Claudia Cristina de Aguiar , Rabello Renata dos Santos , Elias Flávia Tavares Silva
Published: June 2017

Objectives: Hospital-based health technology assessment (HTA) has become increasingly important in Brazil due to its strategic importance to promote adoption, incorporation, dissemination, and disinvestment of technologies. A strategy to foster hospital-based HTA was implemented in 2009 by creating hospital-based HTA nuclei (NATS) at university hospitals and other strategic hospitals.

Methods: Between 2011 and 2012, we interviewed board members in twenty-three NATS located in all geographic regions of Brazil to assess their general characteristics, scientific output, and challenges.

Results: Of the total, 65 percent of the NATS belonged to teaching institutions, with 44 percent associated with federal universities. The bulk of their output was in the form of mini-HTA reports. Centers in the Southeast and South of Brazil had the highest production compared with other regions. Lack of expertise and low levels of advanced training were identified as limiting factors in the majority of centers.

Conclusions: The experience of the initial twenty-three NATS could be considered positive and has led to the creation of new ones around Brazil. Regional disparities in workload, production, and technical training should be targeted by new policies toward hospital-based HTA in Brazil. The limits and possibilities for intensifying the strategy relate to continuous investment in priority studies, which simultaneously, allow professionals who work in hospitals to receive continued education and produce relevant HTA work in a timely manner.
Fifty Years of Collecting: The Sale of Ancient Maya Antiquities at Sotheby’s
Authors: Tremain Cara Grace
Published: June 2017

Pre-Columbian antiquities, particularly those from the Maya region, are highly sought after on the international art market. Large auction houses such as Sotheby’s have dedicated pre-Columbian departments and annual auctions, for which sales catalogues are created. These catalogues offer insight into market trends and allow the volume of antiquities being bought and sold to be monitored. The following study records the public sale of Maya antiquities at Sotheby’s over a period slightly exceeding 50 years from 1963 to 2016. More than 3,500 artifacts were offered for sale during this period, of which more than 80 percent did not have associated provenance information. The data suggests that the volume of Maya antiquities offered for sale at Sotheby’s public auctions have been steadily decreasing since the 1980s, but their relative value has increased. Quantitative studies of auction sales such as this one can be useful in monitoring the market for illegal antiquities and forgeries.
The use of nesiritide in patients with critical cardiac disease
Authors: Bronicki Ronald A. , Domico Michele , Checchia Paul A. , Kennedy Curtis E. , Akcan-Arikan Ayse
Published: June 2017

Objective

We evaluated the use of nesiritide in children with critical CHD, pulmonary congestion, and inadequate urine output despite undergoing conventional diuretic therapy.

Design

We conducted a retrospective analysis of 11 patients with critical CHD, comprising 18 infusions, each of which occurred during separate hospitalisations. Haemodynamic parameters were assessed, and the stage of acute kidney injury was determined before and throughout the duration of therapy using a standardised definition of acute kidney injury – The Kidney Disease: Improving Global Outcomes criteria.

Patients

Children with critical CHD, pulmonary congestion, and inadequate urinary output despite undergoing diuretic therapy were included.

Measurements and main results

The use of nesiritide was associated with a significant decrease in the maximum and minimum heart rate values and with a trend towards a significant decrease in maximum systolic blood pressure and maximum and minimum central venous pressures. Urine output increased but was not significant. Serum creatinine levels decreased significantly during the course of therapy (−0.26 mg/dl [−0.50, 0.0], p=0.02), and the number of patients who experienced a decrease in the stage of acute kidney injury of 2 or more – where a change in the stage of acute kidney disease of 2 or more was possible, that is, baseline stage >1 – was highly significant (five of 12 patients, 42%, p<0.001).

Conclusions

Nesiritide had a favourable impact on haemodynamics, and its use was not associated with deterioration of renal function in patients with critical CHD.
GIMME A BREAK! IDENTIFICATION AND ESTIMATION OF THE MACROECONOMIC EFFECTS OF MONETARY POLICY SHOCKS IN THE UNITED STATES
Authors: Bacchiocchi Emanuele , Castelnuovo Efrem , Fanelli Luca
Published: June 2017

We employ a non-recursive identification scheme to identify the effects of a monetary policy shock in a Structural Vector Autoregressive (SVAR) model for the US post-WWII quarterly data. The identification of the shock is achieved via heteroskedasticity, and different on-impact macroeconomic responses are allowed for (but not imposed) in each volatility regime. We show that the impulse responses obtained with the suggested non-recursive identification scheme are quite similar to those conditional on a recursive VAR estimated with pre-1984 data. In contrast, recursive vs. non-recursive identification schemes return different short-run responses of output and investment during the Great Moderation. Robustness checks dealing with a different definition of investment, an alternative break-point, and federal funds futures rates as an indicator of the monetary policy stance are documented and discussed.
“WE MUST PERFORM EXPERIMENTS ON SOME LIVING BODY”: ANTIVIVISECTION AND AMERICAN MEDICINE, 1850–1915
Authors: Hausmann Stephen R.
Published: June 2017

This article examines the American Anti-Vivisection Society (AAVS) and its campaign in the late nineteenth and early twentieth centuries to end the practice of live scientific experimentation on animals. In attempting to enact state and federal-level legislative reform, the AAVS ran up against the American Medical Association (AMA), who claimed vivisection was critical to furthering medical advances and who sought to defend their profession's recently won respectability. This article argues that the very public campaign by the AAVS toward political reform pushed the AMA, and medicine more broadly, into the political sphere. The debate over the morality of vivisection at the beginning of the last century was thus critical to creating the politically powerful AMA of the twenty-first century.
The search for isolated BH candidates based on kinematics of pulsars - their former companions in disrupted binaries
Authors: Chmyreva E. , Beskin G. , Dyachenko V. , Karpov S.
Published: June 2017

We propose searching for isolated stellar-mass black hole (BH) candidates based on the fact that more than 50% of radio pulsars have originated in binary systems, where the other component could have evolved into a BH prior to the second supernova event of the system, which caused its disruption. We selected isolated, relatively young radio pulsars with known parallaxes and proper motions and traced their trajectories back to their presumed birth locations. These locations were then analyzed for possible BH candidates based on the available positional, photometric, and spectral data. We present the first results for 2 pulsars, J0139+5814 and J0922+0638. Seven BH candidates were selected for further analysis.
Star Formation Close to Sgr A* and Beyond the Nuclear Cluster
Authors: Yusef-Zadeh Farhad , Wardle Mark
Published: June 2017

Two modes of star formation are involved to explain the origin of young stars near Sgr A*. One is a disk-based mode, which explains the disk of stars orbiting Sgr A*. The other is the standard cloud-based mode observed in the Galactic disk. We discuss each of these modes of star formation and apply these ideas to the inner few parsecs of Sgr A*. In particular, we focus on the latter mode in more detail. We also discuss how the tidal force exerted by the nuclear cluster makes the Roche density approaching zero and contributes to the collapse of molecular clouds located tens of parsecs away from Sgr A*.
Two optical emission components with different variability in V404 Cygni
Authors: Tachibana Yutaro , Yoshii Taketoshi , Kawai Nobuyuki
Published: June 2017

V404 Cygni went into an outburst again on June 15, 2015 after 26 years of quietness. Soon after the notifications, we started intense optical observation campaign of this source. The spectral index between RC and IC-band was stable over the outburst, whereas that between g′ and RC-band varied violently. With the time domain analysis of the multi-color optical light curves, we successfully decomposed optical variations into three components: highly-variable component (HVC), little-variable component (LVC). The loci of the LVC in the color-color diagram is consistent with that of a single temperature blackbody radiation or a multi-color blackbody radiation from a standard accretion disk, while those of the HVC trace that of power-law spectra.
A Statistical Method for Detecting Gravitational Recoils of Supermassive Black Holes in Active Galactic Nuclei
Authors: Raffai P. , Bécsy B. , Haiman Z. , Frei Z.
Published: June 2017

We propose an observational test for gravitationally recoiling supermassive black holes in active galactic nuclei, based on a positive correlation between the velocities of black holes relative to their host galaxies, |Δv|, and their obscuring dust column densities, Σdust, both measured along the line of sight. Our findings using a set of toy models implemented to a Monte Carlo simulation imply that models of the galactic centre and of recoil dynamics can be tested by future observations of the potential Σdust–|Δv| correlation. We have also found that the fraction of obscured quasars decreases with |Δv|, for which the predicted trend can be compared to the observed fraction of type II quasars, and can further test combinations of models we may implement.
Spatial Distribution of the Gamma-ray Bursts and the Cosmological Principle
Authors: Mészáros Attila
Published: June 2017

The Cosmological Principle claims that in the large scale average the visible parts of the universe are isotropic and homogeneous. In year 1998 the author, together with his two colleagues, discovered that the BATSE’s short gamma-ray bursts are not distributed isotropically on the sky. This first discovery was followed by other ones confirming both the existence of anisotropies in the angular distribution of bursts and the existence of huge Gpc structures in the spatial distribution. All this means that these anisotropies should reject the Cosmological Principle, because the large scale averaging hardly can be provided. This was claimed in year 2009. The aim of this contribution is to survey these publications since 1998 till today.
Untriggered search for rapid optical transients with Mini-MegaTORTORA wide-field monitoring system
Authors: Karpov S. , Beskin G. , Biryukov A. , Bondar S. , Ivanov E. , Katkova E. , Orekhova N. , Perkov A. , Sasyuk V.
Published: June 2017

Here we report ongoing efforts for an untriggered search of rapid optical transients of various astrophysical and non-astrophysical origins on time scales down to fractions of a second with Mini-MegaTORTORA. Mini-MegaTORTORA is a novel 9-channel wide-field optical monitoring system in operation since 2014 at Special Astrophysical Observatory on Russian Caucasus.
Observational View of Magnetic Fields in Active Galactic Nuclei Jets
Authors: Hovatta Talvikki
Published: June 2017

According to the currently favored picture, relativistic jets in active galactic nuclei (AGN) are launched in the vicinity of the black hole by magnetic fields extracting energy from the spinning black hole or the accretion disk. In the past decades, various models from shocks to magnetic reconnection have been proposed as the energy dissipation mechanism in the jets. This paper presents a short review on how linear polarization observations can be used to constrain the magnetic field structure in the jets of AGN, and how the observations can be used to constrain the various emission models.
Explosive nucleosynthesis in tidal disruption events of massive white dwarfs, and their debris
Authors: Tanikawa Ataru , Sato Yushi , Nomoto Ken’ichi , Maeda Keiichi , Nakasato Naohito , Hachisu Izumi
Published: June 2017

We perform SPH simulations coupled with nuclear reactions to follow tidal disruption events (TDEs) of white dwarfs (WDs) by intermediate mass black holes (IMBHs). We consider an oxygen-neon-magnesium (ONeMg) WD with 1.2M⊙ as well as a helium (He) WD with 0.3M⊙, and a carbon-oxygen (CO) WD with 0.6M⊙. Our WD models have different numbers of SPH particles, N, up to a few 10 million. We find that nucleosynthesis does not converge against N even for N > 107. For all the WDs, the amount of radioactive nuclei, such as 56Ni, decreases with increasing N. Nuclear reactions might be extinguished for infinitely large N. Our results show that these kinds of TDEs, if solely powered by radioactive decays, are much dimmer optical transients similar to Type Ia supernovae as previously suggested.
Simulation of AGN feedback and its impact on galaxies
Authors: Bourne Martin A.
Published: June 2017

Feedback released during the growth of supermassive black holes is expected to play a key role in shaping black hole-host galaxy co-evolution. Powerful, accretion disc driven winds have been invoked to explain both observed scaling relations (e.g., M − σ) and large-scale outflows with mass outflow rates of ~ 100 − 1000 M⊙ yr−1 and momentum rates of up to ~ 30 LAGN/c. Critically, how these winds couple to the host galaxy depends on if they are momentum or energy conserving. I outline observational signatures that could distinguish between these regimes and discuss their roles in establishing galaxy properties. Furthermore, I discuss high-resolution simulations exploring feedback in a multi-phase medium, highlighting how structural properties of galaxies can impact feedback efficiency. Finally, feedback, in the form of collimated jets, is expected to regulate cooling in galaxy clusters. I discuss new simulations of jet feedback using the moving-mesh code AREPO and outline the scope of our new study.
Tidal Disruption Events and stellar-mass black holes in OGLE and Gaia surveys
Authors: Wyrzykowski Łukasz , Hamanowicz A. , Rybicki K. A.
Published: June 2017

Tidal Disruption Events (TDE) allow to probe the super massive black holes (SMBH) in the cores of galaxies and could be a source of black hole mass growth. We present the search for candidates for TDEs conducted within OGLE and Gaia surveys. Our preliminary results indicate that TDEs can occur in cores of galaxies exhibiting different levels of activity, from quiescent, through weak-AGNs to highly active QSOs. We also present how Gaia can help study the mass distribution of Milky Way single black holes via microlensing.
The Extremes of AGN Variability
Authors: Komossa S. , Grupe D. , Schartel N. , Gallo L. , Gomez J. L. , Kollatschny W. , Kriss G. , Leighly K. , Longinotti A. L. , Parker M. , Santos-Lleo M. , Wilkins D. , Zetzl M.
Published: June 2017

We present results from our ongoing monitoring programs aimed at identifying and understanding Active Galactic Nuclei (AGN) in extreme flux and spectral states. Observations of AGN in extreme states can reveal the nature of the inner accretion flow, the physics of matter under strong gravity, and they provide insight on the properties of ionized absorbers and outflows launched near supermassive black holes (SMBHs). We present new results from our long-term monitoring of IC 3599, WPVS007, and Mrk 335, multi-wavelength follow-ups of the newly identified changing-look AGN HE 1136–2304, and UV–X-ray follow-ups of the binary SMBH candidate OJ 287 after its 2015 optical maximum, now in a new optical-X-ray–high-state.
Observational Progress in Identifying and Characterizing Tidal Disruption Flares
Authors: Cenko S. Bradley
Published: June 2017

I present an overview of observational efforts across the electromagnetic spectrum to identify and study tidal disruption flares (TDFs), when a star wanders too close to a super-massive black hole and is torn apart by tidal forces. In particular I will focus on four unexpected surprises that challenge the most basic analytic picture of these events: 1) large inferred radii for the optical/UV-emitting material; 2) the ubiquity of outflows, detected at radio, X-ray, and UV wavelengths, ranging from speeds of 100 km/s to near the speed of light; 3) the peculiar atomic abundances observed in the UV and optical spectra of these objects; and, 4) the preference for these events to occur in post-starburst galaxies.
Gamma-Ray Bursts Polarization
Authors: Götz Diego , Covino Stefano
Published: June 2017

We review the current observational and theoretical status of the polarization measurements of Gamma-ray Bursts at all wavelengths. Gamma-Ray Bursts are thought to be produced by an ultra-relativistic jet, possibly powered by a black hole. One of the most important open point is the composition of the jet: the energy may be carried out from the central source either as kinetic energy (of baryons and/or pairs), or in electromagnetic form (Poynting flux). The polarization properties are expected to help disentangling main energy carrier. The prompt emission and afterglow polarization are also a powerful diagnostic of the jet geometry.
Extremely Bright GRB160625B with Short-Soft Precursor and long-hard extended emission: Hints for long-term evolution of the GRB Ejecta
Authors: Zhong Shu-Qing , Lü Jing , Lü Hou-Jun , Zhang Hai-Ming , Huang Xiao-Li , Liang En-Wei
Published: June 2017

In this paper, we focus on studying the high energy emission of GRB 160625B. The lightcurve of prompt emission is composed of three episodes: short-soft precursor, hard main burst, and possible long extended emission. The spectra of first and third episode can be fitted by a multi-color blackbody and cutoff power-law model, respectively. However, the spectrum of second episode was contributed by both multi-color blackbody and cutoff power-law. One can estimate the Lorenz factor of jet of first two episodes by invoking photosphere model as Γ0 ~ 175 and 1694, respectively. It suggests that the ejecta of this case evolved from photosphere dominated initially to internal shock later. On the other hand, the optical emission is very bright during the second episode, which is likely a prompt optical emission. Finally, a more shallower normal decay segment appeared, which is consistent with standard external shock model.
How Does Wind Push Water?
Authors: Underwood Emily
Published: June 2017

A new 3-D model shows how wind affects hydrodynamic mixing in a northern Italian lake.
Unexpected genomic features in widespread intracellular bacteria: evidence for motility of marine chlamydiae
Authors: Collingro Astrid , Köstlbacher Stephan , Mussmann Marc , Stepanauskas Ramunas , Hallam Steven J , Horn Matthias
Published: June 2017

Chlamydiae are obligate intracellular bacteria comprising important human pathogens and symbionts of protists. Molecular evidence indicates a tremendous diversity of chlamydiae particularly in marine environments, yet our current knowledge is based mainly on terrestrial representatives. Here we provide first insights into the biology of marine chlamydiae representing three divergent clades. Our analysis of single-cell amplified genomes revealed hallmarks of the chlamydial lifestyle, supporting the ancient origin of their characteristic developmental cycle and major virulence mechanisms. Surprisingly, these chlamydial genomes encode a complete flagellar apparatus, a previously unreported feature. We show that flagella are an ancient trait that was subject to differential gene loss among extant chlamydiae. Together with a chemotaxis system, these marine chlamydiae are likely motile, with flagella potentially playing a role during host cell infection. This study broadens our view on chlamydial biology and indicates a largely underestimated potential to adapt to different hosts and environments.
Recurrent mutation of IGF signalling genes and distinct patterns of genomic rearrangement in osteosarcoma
Authors: Behjati Sam , Tarpey Patrick S. , Haase Kerstin , Ye Hongtao , Young Matthew D. , Alexandrov Ludmil B. , Farndon Sarah J. , Collord Grace , Wedge David C. , Martincorena Inigo , Cooke Susanna L. , Davies Helen , Mifsud William , Lidgren Mathias , Martin Sancha , Latimer Calli , Maddison Mark , Butler Adam P. , Teague Jon W. , Pillay Nischalan , Shlien Adam , McDermott Ultan , Futreal P. Andrew , Baumhoer Daniel , Zaikova Olga , Bjerkehagen Bodil , Myklebost Ola , Amary M. Fernanda , Tirabosco Roberto , Van Loo Peter , Stratton Michael R. , Flanagan Adrienne M. , Campbell Peter J.
Published: June 2017

Osteosarcoma is a primary malignancy of bone that affects children and adults. Here, we present the largest sequencing study of osteosarcoma to date, comprising 112 childhood and adult tumours encompassing all major histological subtypes. A key finding of our study is the identification of mutations in insulin-like growth factor (IGF) signalling genes in 8/112 (7%) of cases. We validate this observation using fluorescence in situ hybridization (FISH) in an additional 87 osteosarcomas, with IGF1 receptor (IGF1R) amplification observed in 14% of tumours. These findings may inform patient selection in future trials of IGF1R inhibitors in osteosarcoma. Analysing patterns of mutation, we identify distinct rearrangement profiles including a process characterized by chromothripsis and amplification. This process operates recurrently at discrete genomic regions and generates driver mutations. It may represent an age-independent mutational mechanism that contributes to the development of osteosarcoma in children and adults alike.
Symmetry-based indicators of band topology in the 230 space groups
Authors: Po Hoi Chun , Vishwanath Ashvin , Watanabe Haruki
Published: June 2017

The interplay between symmetry and topology leads to a rich variety of electronic topological phases, protecting states such as the topological insulators and Dirac semimetals. Previous results, like the Fu-Kane parity criterion for inversion-symmetric topological insulators, demonstrate that symmetry labels can sometimes unambiguously indicate underlying band topology. Here we develop a systematic approach to expose all such symmetry-based indicators of band topology in all the 230 space groups. This is achieved by first developing an efficient way to represent band structures in terms of elementary basis states, and then isolating the topological ones by removing the subset of atomic insulators, defined by the existence of localized symmetric Wannier functions. Aside from encompassing all earlier results on such indicators, including in particular the notion of filling-enforced quantum band insulators, our theory identifies symmetry settings with previously hidden forms of band topology, and can be applied to the search for topological materials.
Atomic and electronic basis for the serrations of refractory high-entropy alloys
Authors: Wang William Yi , Shang Shun Li , Wang Yi , Han Fengbo , Darling Kristopher A. , Wu Yidong , Xie Xie , Senkov Oleg N. , Li Jinshan , Hui Xi Dong , Dahmen Karin A. , Liaw Peter K. , Kecskes Laszlo J. , Liu Zi-Kui
Published: June 2017

Refractory high-entropy alloys present attractive mechanical properties, i.e., high yield strength and fracture toughness, making them potential candidates for structural applications. Understandings of atomic and electronic interactions are important to reveal the origins for the formation of high-entropy alloys and their structure−dominated mechanical properties, thus enabling the development of a predictive approach for rapidly designing advanced materials. Here, we report the atomic and electronic basis for the valence−electron-concentration-categorized principles and the observed serration behavior in high-entropy alloys and high-entropy metallic glass, including MoNbTaW, MoNbVW, MoTaVW, HfNbTiZr, and Vitreloy-1 MG (Zr41Ti14Cu12.5Ni10Be22.5). We find that the yield strengths of high-entropy alloys and high-entropy metallic glass are a power-law function of the electron-work function, which is dominated by local atomic arrangements. Further, a reliance on the bonding-charge density provides a groundbreaking insight into the nature of loosely bonded spots in materials. The presence of strongly bonded clusters and weakly bonded glue atoms imply a serrated deformation of high-entropy alloys, resulting in intermittent avalanches of defects movement.
Metabolite profiling in identifying metabolic biomarkers in older people with late-onset type 2 diabetes mellitus
Authors: Tam Zhi Yang , Ng Sean Pin , Tan Ling Qiao , Lin Chih-Hsien , Rothenbacher Dietrich , Klenk Jochen , Boehm Bernhard Otto ,   SPC Team, Kiat Kelvin Goh Kau , Suwanchaikasem Pipob , Tipthara Pornpimol , Yi Yang Song ,   ActiFE Study Group, Becker T. , Stingl J. , Koenig W. , Riepe M. , Peter R. , Geiger H. , Ludolph A. , Arnim C. v. , Nagel G. , Weinmayr G. , Rapp K. , Denkinger M. D. , Dallmeier D. , Steinacker J. M. , Laszlo R.
Published: June 2017

Regulation of blood glucose requires precise coordination between different endocrine systems and multiple organs. Type 2 diabetes mellitus (T2D) arises from a dysregulated response to elevated glucose levels in the circulation. Globally, the prevalence of T2D has increased dramatically in all age groups. T2D in older adults is associated with higher mortality and reduced functional status, leading to higher rate of institutionalization. Despite the potential healthcare challenges associated with the presence of T2D in the elderly, the pathogenesis and phenotype of late-onset T2D is not well studied. Here we applied untargeted metabolite profiling of urine samples from people with and without late-onset T2D using ultra-performance liquid-chromatography mass-spectrometry (UPLC-MS) to identify urinary biomarkers for late-onset T2D in the elderly. Statistical modeling of measurements and thorough validation of structural assignment using liquid chromatography tandem mass-spectrometry (LC-MS/MS) have led to the identification of metabolite biomarkers associated with late-onset T2D. Lower levels of phenylalanine, acetylhistidine, and cyclic adenosine monophosphate (cAMP) were found in urine samples of T2D subjects validated with commercial standards. Elevated levels of 5′-methylthioadenosine (MTA), which previously has only been implicated in animal model of diabetes, was found in urine of older people with T2D.
A Simple and Rapid Turn On ESIPT Fluorescent Probe for Colorimetric and Ratiometric Detection of Biothiols in Living Cells
Authors: Wang Yi , Zhu Meiqing , Jiang Erkang , Hua Rimao , Na Risong , Li Qing X.
Published: June 2017

Biothiols, such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH), play a key role in an extensive range of physiological processes and biological functions. Therefore, the selective and sensitive detection of intracellular thiols is important for revealing cellular function. In this study, ethyl 2-(4-(acryloyloxy)-3-formylphenyl)-4-methylthiazole-5-carboxylate (NL-AC) was designed and synthesized as a colorimetric and ratiometric fluorescent probe that can be utilized to rapidly, sensitively and selectively detect biothiols in physiological media. The fluorescence intensity of this probe using the three target biothiols at a concentration of 20 equiv. of the probe increased by approximately 6~10-fold in comparison to that without the biothiols in aqueous solution. The limits of detection (LOD) for Cys, Hcy and GSH were 0.156, 0.185, and 1.838 μM, respectively. In addition, both 1H-NMR and MS analyses suggested the mechanism of fluorescence sensing to be excited-state intramolecular proton transfer (ESIPT). The novel colorimetric and ratiometric probe is structurally simple and offers detection within 20 min. Furthermore, this probe can be successfully applied in bioimaging. The results indicate high application potential in analytical chemistry and diagnostics.
Lower school performance in late chronotypes: underlying factors and mechanisms
Authors: Zerbini Giulia , van der Vinne Vincent , Otto Lana K. M. , Kantermann Thomas , Krijnen Wim P. , Roenneberg Till , Merrow Martha
Published: June 2017

Success at school determines future career opportunities. We described a time-of-day specific disparity in school performance between early and late chronotypes. Several studies showed that students with a late chronotype and short sleep duration obtain lower grades, suggesting that early school starting times handicap their performance. How chronotype, sleep duration, and time of day impact school performance is not clear. At a Dutch high school, we collected 40,890 grades obtained in a variety of school subjects over an entire school year. We found that the strength of the effect of chronotype on grades was similar to that of absenteeism, and that late chronotypes were more often absent. The difference in grades between the earliest 20% and the latest 20% of chronotypes corresponds to a drop from the 55th to 43rd percentile of grades. In academic subjects using mainly fluid cognition (scientific subjects), the correlation with grades and chronotype was significant while subjects relying on crystallised intelligence (humanistic/linguistic) showed no correlation with chronotype. Based on these and previous results, we can expand our earlier findings concerning exam times: students with a late chronotype are at a disadvantage in exams on scientific subjects, and when they are examined early in the day.
Challenge of Liquid Stressed Protective Materials and Environmental Persistence of Ebola Virus
Authors: Nikiforuk Aidan M. , Cutts Todd A. , Theriault Steven S. , Cook Bradley W. M.
Published: June 2017

After the largest Ebola virus outbreak in history, experts have attempted to answer how the Zaire ebolavirus species emerged in West Africa and caused chains of human-to-human transmission. The widespread and untimely infection of Health Care Workers (HCW) in the affected countries accelerated spread of the virus within the community. Among the reasons attributed to this trend, it must be considered that HCW were exposed to the virus in their occupational environment. The contribution of environmental conditions to the spread of Ebola in West Africa was examined by investigating the effect of temperature/humidity on the virus’s environmental persistence and by modeling if saturation (liquid stress) allows for penetration of Ebola virus through personal protective equipment (PPE). Ebola-Makona virus persisted on PPE and materials found in outbreak settings for less than 72 hours at 27 °C and 80% relative humidity (RH). A difference in virus penetration was observed between dry (5%, 1/21 tests) and saturated (33%, 7/21 tests) samples of PPE. Infectious virus particles penetrated through saturated coupons of Tyvek Micro Clean, Tychem QC, whole surgical masks and N95 respirators. These findings suggest inclusion of saturation or similar liquid stress simulation in protective equipment testing standards.