bluuebunny/crossref_metadata_2025 huggingface dataset:
Rhein Induces Oxidative Stress and Apoptosis in Mouse Blastocysts and Has Immunotoxic Effects during Embryonic Development
Authors: Huang Chien-Hsun , Chan Wen-Hsiung
Published: September 2017

Rhein, a glucoside chemical compound found in a traditional Chinese medicine derived from the roots of rhubarb, induces cell apoptosis and is considered to have high potential as an antitumor drug. Several previous studies showed that rhein can inhibit cell proliferation and trigger mitochondria-related or endoplasmic reticulum (ER) stress-dependent apoptotic processes. However, the side effects of rhein on pre- and post-implantation embryonic development remain unclear. Here, we show that rhein has cytotoxic effects on blastocyst-stage mouse embryos and induces oxidative stress and immunotoxicity in mouse fetuses. Blastocysts incubated with 5–20 μM rhein showed significant cell apoptosis, as well as decreases in their inner cell mass cell numbers and total cell numbers. An in vitro development assay showed that rhein affected the developmental potentials of both pre- and post-implantation embryos. Incubation of blastocysts with 5–20 μM rhein was associated with increased resorption of post-implantation embryos and decreased fetal weight in an embryo transfer assay. Importantly, in an in vivo model, intravenous injection of dams with rhein (1, 3, and 5 mg/kg body weight/day) for four days resulted in apoptosis of blastocyst-stage embryos, early embryonic developmental injury, and decreased fetal weight. Intravenous injection of dams with 5 mg/kg body weight/day rhein significantly increased the total reactive oxygen species (ROS) content of fetuses and the transcription levels of antioxidant proteins in fetal livers. Additional work showed that rhein induced apoptosis through ROS generation, and that prevention of apoptotic processes effectively rescued the rhein-induced injury effects on embryonic development. Finally, the transcription levels of the innate-immunity related genes, CXCL1, IL-1 β and IL-8, were down-regulated in the fetuses of dams that received intravenous injections of rhein. These results collectively show that rhein has the potential to induce embryonic cytotoxicity and induce oxidative stress and immunotoxicity during the development of mouse embryos.
Getting More Power from Your Flowers: Multi-Functional Flower Strips Enhance Pollinators and Pest Control Agents in Apple Orchards
Authors: Campbell Alistair , Wilby Andrew , Sutton Peter , Wäckers Felix
Published: September 2017

Flower strips are commonly recommended to boost biodiversity and multiple ecosystem services (e.g., pollination and pest control) on farmland. However, significant knowledge gaps remain regards the extent to which they deliver on these aims. Here, we tested the efficacy of flower strips that targeted different subsets of beneficial arthropods (pollinators and natural enemies) and their ecosystem services in cider apple orchards. Treatments included mixes that specifically targeted: (1) pollinators (‘concealed-nectar plants’); (2) natural enemies (‘open-nectar plants’); or (3) both groups concurrently (i.e., ‘multi-functional’ mix). Flower strips were established in alleyways of four orchards and compared to control alleyways (no flowers). Pollinator (e.g., bees) and natural enemy (e.g., parasitoid wasps, predatory flies and beetles) visitation to flower strips, alongside measures of pest control (aphid colony densities, sentinel prey predation), and fruit production, were monitored in orchards over two consecutive growing seasons. Targeted flower strips attracted either pollinators or natural enemies, whereas mixed flower strips attracted both groups in similar abundance to targeted mixes. Natural enemy densities on apple trees were higher in plots containing open-nectar plants compared to other treatments, but effects were stronger for non-aphidophagous taxa. Predation of sentinel prey was enhanced in all flowering plots compared to controls but pest aphid densities and fruit yield were unaffected by flower strips. We conclude that ‘multi-functional’ flower strips that contain flowering plant species with opposing floral traits can provide nectar and pollen for both pollinators and natural enemies, but further work is required to understand their potential for improving pest control services and yield in cider apple orchards.
Resistance Management for Asian Citrus Psyllid, Diaphorina citri Kuwayama, in Florida
Authors: Chen Xue , Stelinski Lukasz
Published: September 2017

The Asian citrus psyllid, Diaphorina citri Kuwayma, is one of the most important pests in citrus production. The objective of this study was to evaluate D. citri resistance management with three insecticide rotations and compare them with no rotation and an untreated check. The different insecticides (modes of action) tested were: dimethoate, imidacloprid, diflubenzuron, abamectin 3% + thiamethoxam 13.9%, and fenpropathrin. Eggs, nymph, and adult psyllids were counted weekly. Five insecticide applications were made in 2016. Insecticide susceptibility was determined by direct comparison with a laboratory susceptible population and field populations before and after all treatments were applied. Rankings of eggs, nymphs, and adults counted in treated plots were significantly lower than in the untreated control plots after each application. Initially, the resistance ratio (RR50) for each rotation model, as compared with laboratory susceptible strain and the field population before application, was less than 5.76 and 4.31, respectively. However, after five applications with dimethoate, the RR50 using the laboratory and pre-treatment field populations was 42.34 and 34.74, respectively. Our results indicate that effectively rotating modes of action can delay and/or prevent development of insecticide resistance in populations of D. citri.
Low Field NMR Determination of pKa Values for Hydrophilic Drugs for Students in Medicinal Chemistry
Authors: Zivkovic Aleksandra , Bandolik Jan , Skerhut Alexander , Coesfeld Christina , Raos Miomir , Zivkovic Nenad , Nikolic Vlastimir , Stark Holger
Published: September 2017

For an interdisciplinary approach on different topics of medicinal and analytical chemistry, we applied a known experimental pKa value determination method on the field of the bench top nuclear magnetic resonance (NMR) spectrometry of some known biologically active pyridine-based drugs, i.e., pyridoxine hydrochloride, isoniazid, and nicotine amide. The chemical shifts of the aromatic ring protons in the 1H NMR spectrum change depending on the protonation status. The data were analyzed on dependence of the chemical shifts by different pH (pD) environments and then the pKa values were calculated. The pKa values obtained were in agreement with the literature data for the compounds, searched by the students on web programs available at our university. The importance of the pKa values in protein-ligand interactions and distribution etc. of drugs was brought up to the students’ attention. In addition, by the use of a free web application for pKa values prediction, students calculated the predicted modeled pKa value. The experimental and in-silico approaches enhance the tool box for undergraduate students in medicinal chemistry.
Erratum for Blamey, N.J.F., et al. The Hydrothermal Fluid Evolution of Vein Sets at the Pipeline Gold Mine, Nevada. Minerals 2017, 7, 100; doi:10.3390/min7060100
Authors: Blamey Nigel , Campbell Andrew , Heizler Matt
Published: September 2017

The authors wish to make the following corrections to the main text in the published paper [1]:[...]
Lean Body Mass Harbors Sensing Mechanisms that Allow Safeguarding of Methionine Homeostasis
Authors: Ingenbleek Yves
Published: September 2017

Protein-depleted states generate allosteric inhibition of liver cystathionine β-synthase (CBS), which governs the first enzymatic step of the transsulfuration cascade, resulting in upstream accretion of homocysteine (Hcy) in body fluids. A similar Hcy increase may arise from normal hepatocytes undergoing experimentally-induced impairment of betaine-homocysteine methyltransferase (BHTM) activity or from components of lean body mass (LBM) submitted to any inflammatory disorder. LBM comprises a composite agglomeration of extrarenal tissues characterized by naturally occurring BHTM inactivity. As a result of cellular injury, LBM releases high concentrations of Hcy into the extracellular space, contrasting with the disruption of normal remethylation pathways. Hyperhomocysteinemia acts as a biomarker, reflecting the severity of insult and operating as an alarm signal. Elevated Hcy levels constitute a precursor pool recognized by a CBS coding region that reacts to meet increased methionine requirements in LBM tissues, using its enhanced production in hepatocytes. Preservation of methionine homeostasis benefits from its high metabolic priority and survival value.
Correction: Nicodemus-Johnson, J.; et al. Fruit and Juice Epigenetic Signatures Are Associated with Independent Immunoregulatory Pathways. Nutrients 2017, 9, 752
Authors: Nicodemus-Johnson Jessie , Sinnott Robert
Published: September 2017

We would like to submit the following correction to our recently published paper [1] due to the error in illustration of the abbreviation eFORGE. The details are as follows:[...]
Anglican Moral Theology and Ecumenical Dialogue
Authors: Sedgwick Peter
Published: September 2017

This article argues that there has been conflict in Roman Catholic moral theology since the 1960s. This has overshadowed, but not prevented, ecumenical dialogue between the Roman Catholic and Anglican Communions, especially in ethics. Theologians from the Anglican tradition can help both the debate in Roman Catholic moral theology and the ecumenical impasse. The article examines the contributions of Richard Hooker, Jeremy Taylor, and Kenneth Kirk from 1600–1920, in the area of fundamental moral theology.
Collaborative Landscape Planning: Co-Design of Ecosystem-Based Land Management Scenarios
Authors: Karrasch Leena , Maier Martin , Kleyer Michael , Klenke Thomas
Published: September 2017

Land management in coastal areas has to cope with impacts of climate change and sea level rise. In Germany, landscape plans assess and organize the spatial allocation of land use as an environmental contribution to general spatial planning. Collaborative planning processes are important to develop sustainable and ecosystem-based strategies to make coastal landscapes climate proof. However, there is little experience with collaborative processes in practical planning in Germany, and probably in other countries as well. This paper conducts an empirical case study in the low-lying coastal areas of northwest Germany. During a collaborative landscape planning process, four different ecosystem-based land management scenarios have been co-designed by regional experts and researchers. The participatory and iterative process included the development of scenario narratives to define planning goals, the use of land use elements and their relations to ecosystem services as planning entities in terms of indicators, the art-based illustrations of the different scenarios, and an evaluation and monitoring of the outcomes by regional experts. The decision-maker group decided on the so-called “actor-based” scenario, which contained freshwater retention areas (polders) to prevent potential uncontrolled flooding of the hinterland. This climate adaptation strategy has been implemented in the regional development plan of the county.
Shipment Consolidation Policy under Uncertainty of Customer Order for Sustainable Supply Chain Management
Authors: Kang Kyunghoon , Hong Ki-sung , Kim Ki Hong , Lee Chulung
Published: September 2017

With increasing concern over the environment, shipment consolidation has become one of a main initiative to reduce CO2 emissions and transportation cost among the logistics service providers. Increased delivery time caused by shipment consolidation may lead to customer’s order cancellation. Thus, order cancellation should be considered as a factor in order uncertainty to determine the optimal shipment consolidation policy. We develop mathematical models for quantity-based and time-based policies and obtain optimality properties for the models. Efficient algorithms using optimal properties are provided to compute the optimal parameters for ordering and shipment decisions. To compare the performances of the quantity-based policy with the time-based policy, extensive numerical experiments are conducted, and the total cost is compared.
Imidazolium-based ionic liquids used as additives in the nanolubrication of silicon surfaces
Authors: Amorim Patrícia M , Ferraria Ana M , Colaço Rogério , Branco Luís C , Saramago Benilde
Published: September 2017

In recent years, with the development of micro/nanoelectromechanical systems (MEMS/NEMS), the demand for efficient lubricants of silicon surfaces intensified. Although the use of ionic liquids (ILs) as additives to base oils in the lubrication of steel/steel or other types of metal/ metal tribological pairs has been investigated, the number of studies involving Si is very low. In this work, we tested imidazolium-based ILs as additives to the base oil polyethylene glycol (PEG) to lubricate Si surfaces. The friction coefficients were measured in a nanotribometer. The viscosity of the PEG + IL mixtures as well as their contact angles on the Si surface were measured. The topography and chemical composition of the substrates surfaces were determined with atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS), respectively. Due to the hygroscopic properties of PEG, the first step was to assess the effect of the presence of water. Then, a series of ILs based on the cations 1-ethyl-3-methylimidazolium [EMIM], 1-butyl-3-methylimidazolium [BMIM], 1-ethyl-3-vinylimidazolium [EVIM], 1-(2-hydroxyethyl)-3-methylimidazolium [C2OHMIM] and 1-allyl-3-methylimidazolium [AMIM] combined with the anions dicyanamide [DCA], trifluoromethanesulfonate [TfO], and ethylsulfate [EtSO4] were added to dry PEG. All additives (2 wt %) led to a decrease in friction coefficient as well as an increase in viscosity (with the exception of [AMIM][TfO]) and improved the Si wettability. The additives based on the anion [EtSO4] exhibited the most promising tribological behavior, which was attributed to the strong interaction with the Si surface ensuring the formation of a stable surface layer, which hinders the contact between the sliding surfaces.
Accounting for the Occlusion Effect with Insert Earphones
Authors: Neave-DiToro Dorothy , DeSantolo Amanda , Bergen Michael , Rubinstein Adrienne
Published: September 2017

Background:There are clinical implications associated with knowing when the occlusion effect (OE) must be accounted for during bone conduction (BC) testing because spurious results can occur when errors are made in this regard. The amount of OE produced when insert earphones
(IEs) are used varies in the literature; thus, further investigation is warranted.Purpose:The purpose of this project was to determine the OE during BC threshold measurements under the following occluding conditions used clinically: when using partial insertion (PI) versus full insertion
(FI) depth and when occluding one versus both ears.Research Design:A descriptive within-subjects design was used in this study.Study Sample:Twenty-two adults with mean four-frequency pure tone averages of 24 dB HL, aged 40‐83 yr, participated.Intervention:BC thresholds
were obtained at 250, 500, and 1000 Hz under seven conditions: (1) both ears unoccluded, (2) left ear occluded with PI, (3) right ear occluded with PI, (4) both ears occluded with PI, (5) left ear occluded with FI, (6) right ear occluded with FI, (7) both ears occluded with FI. For PI, one
half of the length of the IE was beyond the opening of the ear canal. For FI, the lateral edge of the foam insert was flush with the entrance to the ear canal.Data Collection and Analysis:Mean OEs were compared with previously published data. In addition, variability in the data was
examined using frequency distribution plots as well as cumulative frequency and percentile values.Results:Mean OEs of 5‐13 dB were present in all but the FI condition at 1000 Hz where the OE was <3 dB. Differences between PI and FI conditions were present at each frequency
measured, irrespective of whether one or both ears were occluded. The shifts in threshold were consistently more prevalent and greater for the PI than the FI conditions overall. Mean differences between the one-ear and both-ears conditions were not clinically significant. Clinically significant
variability in the data was noted, except when comparing the one-ear versus both-ears conditions.Conclusions:Occluding the ear during initial BC measurements may artificially improve the thresholds and create or exaggerate an air-bone gap. Thus, initial BC testing should be performed
unoccluded at 250, 500, and 1000 Hz. There is a need to account for the OE even when the IE is flush with the ear canal to avoid insufficient masking.
Financing Long-Term Services and Supports: Continuity and Change
Authors: Wiener Joshua M. , Knowles Mary E. , White Erin E.
Published: September 2017

This article provides an overview of financing for long-term services and supports (LTSS) in the United States, paying special attention to how it has changed and not changed over the last 30 years. Although LTSS expenditures have increased greatly (like the rest of health care), the broad outline of the financing system has remained remarkably constant. Medicaid—a means-tested program—continues to dominate LTSS financing, while private long-term care insurance plays a minor role. High out-of-pocket costs and spend-down to Medicaid because of those high costs continue to be hallmarks of the system. Although many major LTSS financing reform proposals were introduced over this period, none was enacted—except the Community Living Assistance Services and Supports Act, which was repealed before implementation because of concerns about adverse selection. The one major change during this time period has been the very large increase in Medicare spending for post-acute services, such as short-term skilled nursing facility and home health care. With the aging of the population, demand for LTSS is likely to increase, placing strain on the existing system.
Quasar Rain: The Broad Emission Line Region as Condensations in the Warm Accretion Disk Wind
Authors: Elvis Martin
Published: September 2017

The origin of the broad emission line region (BELR) in quasars and active galactic nuclei is still unclear. I propose that condensations form in the warm, radiation-pressure-driven, accretion disk wind of quasars creating the BEL clouds and uniting them with the other two manifestations of cool (∼104 K) gas in quasars, the low ionization phase of the warm absorbers (WAs) and the clouds causing X-ray eclipses. The cool clouds will condense quickly (days to years), before the WA outflows reach escape velocity (which takes months to centuries). Cool clouds form in equilibrium with the warm phase of the wind because the rapidly varying X-ray quasar continuum changes the force multiplier, causing pressure waves to move gas into stable locations in pressure–temperature space. The narrow range of two-phase equilibrium densities may explain the (luminosity)

scaling of the BELR size, while the scaling of cloud formation timescales could produce the Baldwin effect. These dense clouds have force multipliers of order unity and so cannot be accelerated to escape velocity. They fall back on a dynamical timescale (months to centuries), producing an inflow that rains down toward the central black hole. As they soon move at Mach ∼10–100 with respect to the WA outflow, these “raindrops” will be rapidly destroyed within months. This rain of clouds may produce the elliptical BELR orbits implied by velocity-resolved reverberation mapping in some objects and can explain the opening angle and destruction timescale of the narrow “cometary” tails of the clouds seen in X-ray eclipse observations. Some consequences and challenges of this “quasar rain” model are presented, along with several avenues for theoretical investigation.
First Detection of a Strong Magnetic Field on a Bursty Brown Dwarf: Puzzle Solved
Authors: Berdyugina S. V. , Harrington D. M. , Kuzmychov O. , Kuhn J. R. , Hallinan G. , Kowalski A. F. , Hawley S. L.
Published: September 2017

We report the first direct detection of a strong, 5 kG magnetic field on the surface of an active brown dwarf. LSR J1835+3259 is an M8.5 dwarf exhibiting transient radio and optical emission bursts modulated by fast rotation. We have detected the surface magnetic field as circularly polarized signatures in the 819 nm sodium lines when an active emission region faced the Earth. Modeling Stokes profiles of these lines reveals the effective temperature of 2800 K and log gravity acceleration of 4.5. These parameters place LSR J1835+3259 on evolutionary tracks as a young brown dwarf with the mass of

and age of 22 ± 4 Myr. Its magnetic field is at least 5.1 kG and covers at least 11% of the visible hemisphere. The active region topology recovered using line profile inversions comprises hot plasma loops with a vertical stratification of optical and radio emission sources. These loops rotate with the dwarf in and out of view causing periodic emission bursts. The magnetic field is detected at the base of the loops. This is the first time that we can quantitatively associate brown dwarf non-thermal bursts with a strong, 5 kG surface magnetic field and solve the puzzle of their driving mechanism. This is also the coolest known dwarf with such a strong surface magnetic field. The young age of LSR J1835+3259 implies that it may still maintain a disk, which may facilitate bursts via magnetospheric accretion, like in higher-mass T Tau-type stars. Our results pave a path toward magnetic studies of brown dwarfs and hot Jupiters.
On the Nature of Off-limb Flare Continuum Sources Detected by SDO/HMI
Authors: Heinzel P. , Kleint L. , Kašparová J. , Krucker S.
Published: September 2017

The Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory has provided unique observations of off-limb flare emission. White-light continuum enhancements were detected in the “continuum” channel of the Fe 6173 Å line during the impulsive phase of the observed flares. In this paper we aim to determine which radiation mechanism is responsible for such enhancement being seen above the limb, at chromospheric heights around or below 1000 km. Using a simple analytical approach, we compare two candidate mechanisms, the hydrogen recombination continuum (Paschen) and the Thomson continuum due to scattering of disk radiation on flare electrons. Both mechanisms depend on the electron density, which is typically enhanced during the impulsive phase of a flare as the result of collisional ionization (both thermal and also non-thermal due to electron beams). We conclude that for electron densities higher than 1012 cm−3, the Paschen recombination continuum significantly dominates the Thomson scattering continuum and there is some contribution from the hydrogen free–free emission. This is further supported by detailed radiation-hydrodynamical (RHD) simulations of the flare chromosphere heated by the electron beams. We use the RHD code FLARIX to compute the temporal evolution of the flare-heating in a semi-circular loop. The synthesized continuum structure above the limb resembles the off-limb flare structures detected by HMI, namely their height above the limb, as well as the radiation intensity. These results are consistent with recent findings related to hydrogen Balmer continuum enhancements, which were clearly detected in disk flares by the IRIS near-ultraviolet spectrometer.
A Theoretical Model of X-Ray Jets from Young Stellar Objects
Authors: Takasao Shinsuke , Suzuki Takeru K. , Shibata Kazunari
Published: September 2017

There is a subclass of X-ray jets from young stellar objects that are heated very close to the footpoint of the jets, particularly DG Tau jets. Previous models have attributed the strong heating to shocks in the jets. However, the mechanism that localizes the heating at the footpoint remains puzzling. We presented a different model of such X-ray jets, in which the disk atmosphere is magnetically heated. Our disk corona model is based on the so-called nanoflare model for the solar corona. We show that the magnetic heating near the disks can result in the formation of a hot corona with a temperature of ≳106 K, even if the average field strength in the disk is moderately weak, ≳1 G. We determine the density and the temperature at the jet base by considering the energy balance between the heating and cooling. We derive the scaling relations of the mass-loss rate and terminal velocity of jets. Our model is applied to the DG Tau jets. The observed temperature and estimated mass-loss rate are consistent with the prediction of our model in the case of a disk magnetic field strength of ∼20 G and a heating region of <0.1 au. The derived scaling relation of the temperature of X-ray jets could be a useful tool for estimating the magnetic field strength. We also find that the jet X-ray can have a significant impact on the ionization degree near the disk surface and the dead zone size.
3XMM J181923.7–170616: An X-Ray Binary with a 408 s Pulsar
Authors: Qiu Hao , Zhou Ping , Yu Wenfei , Li Xiangdong , Xu Xiaojie
Published: September 2017

We carry out a dedicated study of 3XMM J181923.7–170616 with an approximate pulsation period of 400 s using the XMM-Newton and Swift observations spanning across nine years. We have refined the period of the source to 407.904(7) s (at epoch MJD 57142) and constrained the 1σ upper limit on the period derivative

. The source radiates hard, persistent X-ray emission during the observation epochs, which is best described by an absorbed power-law model (Γ ∼ 0.2–0.8) plus faint Fe lines at 6.4 and 6.7 keV. The X-ray flux revealed a variation within a factor of 2, along with a spectral hardening as the flux increased. The pulse shape is sinusoid-like and the spectral properties of different phases do not present significant variation. The absorption

(

) is similar to the total Galactic hydrogen column density along the direction, indicating that it is a distant source. A search for the counterpart in optical and near-infrared surveys reveals a low-mass K-type giant, while the existence of a Galactic OB supergiant is excluded. A symbiotic X-ray binary (SyXB) is the favored nature of 3XMM J181923.7–170616 and can essentially explain the low luminosity of

, slow pulsation, hard X-ray spectrum, and possible K3 III companion. An alternative explanation of the source is a persistent Be X-ray binary (BeXB) with a companion star no earlier than B3-type.
An Upper Limit on the Milky Way Mass from the Orbit of the Sagittarius Dwarf Satellite
Authors: Dierickx Marion I. P. , Loeb Abraham
Published: September 2017

As one of the most massive Milky Way (MW) satellites, the Sagittarius dwarf galaxy played an important role in shaping the Galactic disk and stellar halo morphologies. The disruption of Sagittarius over several close-in passages has populated the halo of our Galaxy with large-scale tidal streams and offers a unique diagnostic tool for measuring its gravitational potential. Here, we test different progenitor mass models for the MW and Sagittarius by modeling the full infall of the satellite. We constrain the mass of the Galaxy based on the kinematics of the satellite remnant and multiple tidal streams of Sagittarius. Our semianalytic modeling of the orbital dynamics agrees with full N-body simulations, and favors low values for the MW mass,

. This conclusion eases the tension between ΛCDM and the observed parameters of the MW satellites.
3D Magnetohydrodynamic Models of Nonthermal Photon Emission in the Binary System γ2 Velorum
Authors: Reitberger K. , Kissmann R. , Reimer A. , Reimer O.
Published: September 2017

Recent reports claiming an association of the massive star binary system

Velorum (WR 11) with a high-energy γ-ray source observed by Fermi-LAT contrast the so far exclusive role of η Carinae as the hitherto only detected γ-ray emitter in the source class of particle-accelerating colliding-wind binary (CWB) systems. We offer support to this claim of association by providing dedicated model predictions for the nonthermal photon emission spectrum of

Velorum. We use 3D magnetohydrodynamic modeling (MHD) to investigate the structure and conditions of the wind-collision region (WCR) of

Velorum including the important effect of radiative braking in the stellar winds. A transport equation is then solved for the entire computational domain to study the propagation of relativistic electrons and protons. The resulting distributions of particles are subsequently used to compute nonthermal photon emission components. In agreement with observation in X-ray spectroscopy, our simulations yield a large shock-cone opening angle. We find the nonthermal γ-ray emission of

Velorum to be of hadronic origin owing to the strong radiation fields in the binary system, which inhibit the acceleration of electrons to energies sufficiently high for efficient inverse-Compton radiation. We also discuss the strong dependence of a hadronic γ-ray component on the energy-dependent diffusion used in the simulations. Of two mass-loss rates for the WR star found in literature, only the higher rate is able to accommodate the observed γ-ray spectrum with reasonable values for important simulation parameters such as the injection ratio of high-energy particles within the WCR.
Properties of the Intergalactic Magnetic Field Constrained by Gamma-Ray Observations of Gamma-Ray Bursts
Authors: Veres P. , Dermer C. D. , Dhuga K. S.
Published: September 2017

The magnetic field in intergalactic space gives important information about magnetogenesis in the early universe. The properties of this field can be probed by searching for radiation of secondary e
+
e
− pairs created by TeV photons that produce GeV range radiation by Compton-scattering cosmic microwave background photons. The arrival times of the GeV “echo” photons depend strongly on the magnetic field strength and coherence length. A Monte Carlo code that accurately treats pair creation is developed to simulate the spectrum and time-dependence of the echo radiation. The extrapolation of the spectrum of powerful gamma-ray bursts (GRBs) like GRB 130427A to TeV energies is used to demonstrate how the intergalactic magnetic field can be constrained if it falls in the 10−21–10−17 G range for a 1 Mpc coherence length.
No Neon, but Jets in the Remarkable Recurrent Nova M31N 2008-12a?—Hubble Space Telescope Spectroscopy of the 2015 Eruption
Authors: Darnley M. J. , Hounsell R. , Godon P. , Perley D. A. , Henze M. , Kuin N. P. M. , Williams B. F. , Williams S. C. , Bode M. F. , Harman D. J. , Hornoch K. , Link M. , Ness J.-U. , Ribeiro V. A. R. M. , Sion E. M. , Shafter A. W. , Shara M. M.
Published: September 2017

The 2008 discovery of an eruption of M31N 2008-12a began a journey on which the true nature of this remarkable recurrent nova continues to be revealed. M31N 2008-12a contains a white dwarf (WD) close to the Chandrasekhar limit, accreting at a high rate from its companion, and undergoes thermonuclear eruptions that are observed yearly and may even be twice as frequent. In this paper, we report on Hubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectroscopy taken within days of the predicted 2015 eruption, coupled with Keck spectroscopy of the 2013 eruption. Together, this spectroscopy permits the reddening to be constrained to

E
(
B
−
V
)
=
0.10
±
0.03

. The UV spectroscopy reveals evidence for highly ionized, structured, and high-velocity ejecta at early times. No evidence for neon is seen in these spectra, however, but it may be that little insight can be gained regarding the composition of the WD (CO versus ONe).
CARMA Survey toward Infrared-bright Nearby Galaxies (STING). IV. Spatially Resolved 13CO in Spiral Galaxies
Authors: Cao Yixian , Wong Tony , Xue Rui , Bolatto Alberto D. , Blitz Leo , Vogel Stuart N. , Leroy Adam K. , Rosolowsky Erik
Published: September 2017

We present a

mapping survey of 12 nearby galaxies from the CARMA STING sample. The line intensity ratio

is derived to study the variations in molecular gas properties. For 11 galaxies where it can be measured with high significance, the spatially resolved

on (sub)kiloparsec scales varies by up to a factor of 3–5 within a galaxy. Lower

values are usually found in regions with weaker

. We attribute this apparent trend to a bias against measuring large

values when

is weak. Limiting our analysis to the

-bright regions that are less biased, we do not find that

on (sub)kiloparsec scales correlate with galactocentric distance, velocity dispersion, or the star formation rate. The lack of correlation between star formation rate and

 indicates that the CO optical depth is not sensitive to stellar energy input, or that any such sensitivity is easily masked by other factors. Extending the analysis to all regions with

 emission by spectral stacking, we find that 5 out of 11 galaxies show higher stacked

 for galactocentric radii of

and

yr−1 kpc−2, which could result from a greater contribution from diffuse gas. Moreover, significant galaxy-to-galaxy variations are found in

, but the global

does not strongly depend on dust temperature, inclination, or metallicity of the galaxy.
Constraints from Dust Mass and Mass Accretion Rate Measurements on Angular Momentum Transport in Protoplanetary Disks
Authors: Mulders Gijs D. , Pascucci Ilaria , Manara Carlo F. , Testi Leonardo , Herczeg Gregory J. , Henning Thomas , Mohanty Subhanjoy , Lodato Giuseppe
Published: September 2017

In this paper, we investigate the relation between disk mass and mass accretion rate to constrain the mechanism of angular momentum transport in protoplanetary disks. We find a correlation between dust disk mass and mass accretion rate in Chamaeleon I with a slope that is close to linear, similar to the one recently identified in Lupus. We investigate the effect of stellar mass and find that the intrinsic scatter around the best-fit

–

and

–

relations is uncorrelated. We simulate synthetic observations of an ensemble of evolving disks using a Monte Carlo approach and find that disks with a constant α viscosity can fit the observed relations between dust mass, mass accretion rate, and stellar mass but overpredict the strength of the correlation between disk mass and mass accretion rate when using standard initial conditions. We find two possible solutions. In the first one, the observed scatter in

and

is not primordial, but arises from additional physical processes or uncertainties in estimating the disk gas mass. Most likely grain growth and radial drift affect the observable dust mass, while variability on large timescales affects the mass accretion rates. In the second scenario, the observed scatter is primordial, but disks have not evolved substantially at the age of Lupus and Chamaeleon I owing to a low viscosity or a large initial disk radius. More accurate estimates of the disk mass and gas disk sizes in a large sample of protoplanetary disks, through either direct observations of the gas or spatially resolved multiwavelength observations of the dust with ALMA, are needed to discriminate between both scenarios or to constrain alternative angular momentum transport mechanisms such as MHD disk winds.
Modeling a Propagating Sawtooth Flare Ribbon Structure as a Tearing Mode in the Presence of Velocity Shear
Authors: Parker Jacob , Longcope Dana
Published: September 2017

On 2014 April 18 (SOL2014-04-18T13:03), an M-class flare was observed by IRIS. The associated flare ribbon contained a quasi-periodic sawtooth pattern that was observed to propagate along the ribbon, perpendicular to the IRIS spectral slit, with a phase velocity of ∼15 km s−1. This motion resulted in periodicities in both intensity and Doppler velocity along the slit. These periodicities were reported by Brannon et al. to be approximately ±0.″5 in position and ±20 km s−1 in velocity and were measured to be ∼180° out of phase with one another. This quasi-periodic behavior has been attributed by others to bursty or patchy reconnection and slipping occurring during three-dimensional magnetic reconnection. Though able to account for periodicities in both intensity and Doppler velocity, these suggestions do not explicitly account for the phase velocity of the entire sawtooth structure or the relative phasing of the oscillations. Here we propose that the observations can be explained by a tearing mode (TM) instability occurring at a current sheet across which there is also a velocity shear. Using a linear model of this instability, we reproduce the relative phase of the oscillations, as well as the phase velocity of the sawtooth structure. We suggest a geometry and local plasma parameters for the April 18 flare that would support our hypothesis. Under this proposal, the combined spectral and spatial IRIS observations of this flare may provide the most compelling evidence to date of a TM occurring in the solar magnetic field.
Deep Chandra Survey of the Small Magellanic Cloud. II. Timing Analysis of X-Ray Pulsars
Authors: Hong JaeSub , Antoniou Vallia , Zezas Andreas , Haberl Frank , Sasaki Manami , Drake Jeremy J. , Plucinsky Paul P. , Laycock Silas
Published: September 2017

We report the timing analysis results of X-ray pulsars from a recent deep Chandra survey of the Small Magellanic Cloud (SMC). We analyzed a total exposure of 1.4 Ms from 31 observations over a 1.2 deg2 region in the SMC under a Chandra X-ray Visionary Program. Using the Lomb–Scargle and epoch-folding techniques, we detected periodic modulations from 20 pulsars and a new candidate pulsar. The survey also covered 11 other pulsars with no clear sign of periodic modulation. The 0.5–8 keV X-ray luminosity (L

X
) of the pulsars ranges from 1034 to 1037 erg s−1 at 60 kpc. All of the Chandra sources with L

X
 ≳ 4 × 1035 erg s−1 exhibit X-ray pulsations. The X-ray spectra of the SMC pulsars (and high-mass X-ray binaries) are in general harder than those of the SMC field population. All but SXP 8.02 can be fitted by an absorbed power-law model with a photon index of Γ ≲ 1.5. The X-ray spectrum of the known magnetar SXP 8.02 is better fitted with a two-temperature blackbody model. Newly measured pulsation periods of SXP 51.0, SXP 214, and SXP 701, are significantly different from the previous XMM-Newton and RXTE measurements. This survey provides a rich data set for energy-dependent pulse profile modeling. Six pulsars show an almost eclipse-like dip in the pulse profile. Phase-resolved spectral analysis reveals diverse spectral variations during pulsation cycles: e.g., for an absorbed power-law model, some exhibit an (anti)-correlation between absorption and X-ray flux, while others show more intrinsic spectral variation (i.e., changes in photon indices).
Short COI markers for freshwater macroinvertebrate metabarcoding
Authors: Vamos Ecaterina , Elbrecht Vasco , Leese Florian
Published: September 2017

Species diversity of metazoan bulk samples can be rapidly assessed using cytochrome c oxidase I (COI) metabarcoding. However, in some applications often only degraded DNA is available, e.g. from poorly conserved museum specimens, environmental DNA (eDNA) filtered from water or gut content analyses. Here universal primer sets targeting only a short COI fragment are advantageous, as they often can still amplify short DNA fragments. Using PrimerMiner, we optimised two universal primer sets targeting freshwater macroinvertebrates based on NCBI and BOLD reference sequences. The fwh1 and fwh2 primer sets targeting a 178 and 205 bp region were tested in vitro by sequencing previously used freshwater macroinvertebrate mock communities as well as three monitoring samples from Romanian streams of unknown composition. They were further evaluated in silico for their suitability to amplify other insect groups. The fwh1 primer sets showed the most consistent amplification in silico and in vitro, detecting 92% of the taxa present in the mock communities, and allowing clear differentiation between the three macroinvertebrate communities from the Romanian streams. In silico analysis indicates that the short primers are likely to perform well even for non-freshwater insects. Comparing the performance of the new fwh1 primer sets to a highly degenerate primer set targeting a longer fragment (BF2+BR2) revealed that detection efficiency is slightly lower for the new primer set. Nevertheless, the shorter new primer pairs might be useful for studies that have to rely on degraded or poorly conserved DNA and thus be of importance for biomonitoring, conservation biological or molecular ecological studies. Furthermore, our study highlights the need for in silico evaluation of primer sets in order to detect design errors in primers (fwhR2) and find optimal universal primer sets for the target taxa of interest.
Keep calm and don’t overreact . Le président Trump, le terrorisme et la menace existentielle
Authors: Andorra Alexandre
Published: September 2017

Élu président, Donald Trump doit répondre en plus de 140 caractères à des questions primordiales, notamment sur l’intensité de la menace terroriste. Selon lui, la mouvance radicale salafiste constitue la première menace existentielle contre les États-Unis. S’il maintenait cette posture, il tomberait dans les pièges tendus par le salafisme djihadiste. Malgré tout l’espace médiatique et politique qu’elle occupe, cette mouvance ne menace pas l’existence des États-Unis. Réelle mais limitée, elle correspond à une menace majeure – que D. Trump pourrait transformer, par un discours trop belliqueux, en menace existentielle. Complexe, cette menace exige une stratégie rationnelle, factuelle et réactive, exploitant tous les leviers de puissance et permettant à Washington de se concentrer sur les menaces véritablement existentielles.
Assessing average annual air temperature trends using the Mann–Kendall test in Kosovo
Authors: Gavrilov Milivoj B. , Marković Slobodan B. , Janc Natalija , Nikolić Milena , Valjarević Aleksandar , Komac Blaž , Zorn Matija , Punišić Milan , Bačević Nikola
Published: September 2017

The annual trends of surface mean monthly air temperature and monthly extreme temperatures were analyzed from ten meteorological stations in Kosovo. The data refer to observation periods between 1949 and 1999 for four stations, and observation periods between 1965 and 1999 for the remaining six stations. Trends were analyzed for nine time series. Positive trends were found in six series, and negative trends were found in three series. After an assessment of these trends using the Mann–Kendall test, positive trends were confirmed in four series, a negative trend was confirmed in one series, and in one series there was no trend, whereas trends were characterized as slightly positive in two time series and slightly negative in one series.
Changes in discharge regimes of rivers in Croatia
Authors: Čanjevac Ivan , Orešić Danijel
Published: September 2017

This paper presents the results of the first comprehensive national analysis of changes in discharge regimes of rivers in Croatia. Seven types of discharge regimes have been defined for rivers in Croatia. We analyzed the changes in discharge regimes of all types, comparing the standard period from 1961 to 1990 with the most recent period from 1990 to 2009. We found evidence of a redistribution of discharge throughout the year, an increase in autumn and winter discharges (especially for rivers dominantly fed by snowmelt), and a decrease in summer discharge values. Furthermore, we detected a change in the month of the appearance of mean discharge maxima and minima. In most cases, the changes can be explained by changes in the regime of climate elements (temperature, precipitation, and evapotranspiration). The results are consistent with those from upstream countries; that is, Slovenia, Austria, and Bosnia and Herzegovina.
Eastern European cities as command and control centres in a time of economic crisis
Authors: Raźniak Piotr , Dorocki Sławomir , Winiarczyk-Raźniak Anna
Published: September 2017

This article describes the command and control function of eastern European cities based on the financial performance of the largest corporations with headquarters in the region and the impact of selected sectors on this function. Research has shown that, despite the global economic crisis of 2008–2012, the revenue and net income of the companies studied have increased to some extent. Currently, the strongest “command and control cities” in eastern Europe are Warsaw and Prague. The sector that exerts the greatest influence on the regional command and control function in eastern Europe is the consumer business and transportation sector. The economic crisis has also produced a geographical pattern in eastern Europe that runs counter to current global trends: companies in the region currently tend to concentrate their headquarters in fewer cities, which is becoming common in other parts of the world. The article employs a standardization method based on the mean and standard deviation of financial values for each corporation studied.
Classification of regional and thematic approaches in school textbooks on the geography of Europe
Authors: Senegačnik Jurij
Published: September 2017

Regional and thematic approaches are two basic approaches in geography, and they are found in many combinations and variants in textbooks. An extensive analysis of textbook approaches showed that a detailed classification of these approaches does not currently exist. The main purpose of this study was to fill this gap with the first attempt at a detailed classification of all possible approaches in European textbooks devoted in part or in full to examining the geography of Europe. To this end, it was also necessary to review the terminology and redefine some concepts. The study is based on an analysis of 450 textbooks from twenty-eight European countries using the method of content analysis. It resulted in four classification schemes: a scheme for geography in textbooks in general, and schemes for three approaches used in exploring the regional geography of Europe. Any European textbook covering the geography of Europe can be classified using these schemes.
The enhancement of cultural landscapes in mountain environments: An artificial channel history (Torrent-Neuf, Canton Valais, Switzerland) and the role of trees as natural archives of water flow changes
Authors: Bollati Irene , Reynard Emmanuel , Cagnin Davide , Pelfini Manuela
Published: September 2017

Cultural landscapes represent one of the best examples of the interaction between human and natural environment and cultural trails are an effective way for their valorization. The Torrent-Neuf (Canton Valais, Switzerland) is a cultural trail realized in 2009 along one of the artificial channels used in the region since Medieval times to move water resources from tributary valleys to irrigated lands. Slope instability processes and high maintenance costs provoked the abandonment of the artificial channel in 1934. In 2005 water flow was restored in it. Dendrochronological analyses, carried out on trees growing along the artificial channel banks, allowed collecting information about natural and man-induced hydrological changes, contributing to increase the global value of the whole area.
Multi-criteria assessment of less favoured areas: A state level
Authors: Pažek Karmen , Irgolič Aleš , Turk Jernej , Borec Andreja , Prišenk Jernej , Kolenko Matej , Rozman Črtomir
Published: September 2017

The paper present a multi-criteria decision DEXi model for assessment of less favoured areas (LFAs). The tool enables easier assessment of farming in different areas of Slovene LFAs with respect to criteria of sustainability. Analysis of LFAs and final integration of the assessment of LFAs depend upon various criteria. In this paper we analyze individual LFAs and farming systems in these areas at the state level with respect to criteria of sustainability and farming potential.