bluuebunny/crossref_metadata_2025 huggingface dataset:
Hierarchical fiducial marker design for pose estimation in large‐scale scenarios
Authors: Wang Hao , Shi Zongying , Lu Geng , Zhong Yisheng
Published: March 2018

In this paper, a hierarchical fiducial marker, called HArCo, is designed to guarantee a smooth pose estimation for large‐scale applications. HArCo markers have a visually identifiable structure on multiple scales, so they can be used for consistent pose estimation across a range of altitudes. Experimental results are presented to validate the performance of the proposed methodologies; oscillating platform landing experiments were conducted to show the ability of HArCo to be used in real landing tasks on the deck of a ship.
The AutoSOAR autonomous soaring aircraft, part 1: Autonomy algorithms
Authors: Depenbusch Nathan T. , Bird John J. , Langelaan Jack W.
Published: March 2018

Autonomous soaring has the potential to greatly improve both the range and endurance of small robotic aircraft. This paper describes an autonomous soaring system that generates a dynamic map of lift sources (thermals) in the environment and uses this map for online flight planning and decision making. Components of the autonomy algorithm include thermal mapping, explore/exploit decision making, navigation, optimal airspeed computation, thermal centering control, and energy state estimation. A finite state machine manages the aircraft behavior during flight and determines when changing behavior is appropriate. A complete system to enable autonomous soaring is described with special attention paid to practical considerations encountered during flight testing. A companion paper describes the hardware implementation of this system and the results of a flight test campaign conducted at Aberdeen Proving Ground in September 2015.
Necklace‐Like Silicon Carbide and Carbon Nanocomposites Formed by Steady Joule Heating
Authors: Xie Hua , Fu Kun , Yang Chunpeng , Yao Yonggang , Rao Jiancun , Zhou Yubing , Liu Boyang , Kirsch Dylan , Hu Liangbing
Published: March 2018

Silicon carbide (SiC)/carbon nanocomposites exhibit outstanding physical properties as well as chemical stability and can be utilized in a variety of potential applications. To synthesize SiC/C nanocomposites requires high specific surface area, moderate agglomeration, and good interfacial interaction with the substrate. However, the synthesis of these desired SiC/C nanocomposites requires amelioration in two critical aspects—improving the bond strength between C and SiC and dispersing SiC homogenously to avoid agglomeration. In this work, a Joule heating method is used to synthesize SiC/C necklace‐like nanocomposite fibers from electrospun C/Si nanofibers. A controlled current is induced to heat the C/Si nanofibers to ≈2000 K, promoting the in situ reaction between Si nanoparticles and carbon fibers to create SiC nanoparticles. SiC nanoparticles are uniformly formed in the composites with high specific surface area and strong bonding with the carbon nanofibers. The synthesis of SiC demonstrates feasibility toward in situ fabrication of unagglomerated carbide nanoparticles on a carbon‐based nanofiber with desirable interconnection bond strength.
Quantifying Seining Detection Probability for Fishes of Great Plains Sand‐Bed Rivers
Authors: Mollenhauer Robert , Logue Daniel , Brewer Shannon K.
Published: March 2018

Species detection error (i.e., imperfect and variable detection probability) is an essential consideration when investigators map distributions and interpret habitat associations. When fish detection error that is due to highly variable instream environments needs to be addressed, sand‐bed streams of the Great Plains represent a unique challenge. We quantified seining detection probability for diminutive Great Plains fishes across a range of sampling conditions in two sand‐bed rivers in Oklahoma. Imperfect detection resulted in underestimates of species occurrence using naïve estimates, particularly for less common fishes. Seining detection probability also varied among fishes and across sampling conditions. We observed a quadratic relationship between water depth and detection probability, in which the exact nature of the relationship was species‐specific and dependent on water clarity. Similarly, the direction of the relationship between water clarity and detection probability was species‐specific and dependent on differences in water depth. The relationship between water temperature and detection probability was also species dependent, where both the magnitude and direction of the relationship varied among fishes. We showed how ignoring detection error confounded an underlying relationship between species occurrence and water depth. Despite imperfect and heterogeneous detection, our results support that determining species absence can be accomplished with two to six spatially replicated seine hauls per 200‐m reach under average sampling conditions; however, required effort would be higher under certain conditions. Detection probability was low for the Arkansas River Shiner Notropis girardi, which is federally listed as threatened, and more than 10 seine hauls per 200‐m reach would be required to assess presence across sampling conditions. Our model allows scientists to estimate sampling effort to confidently assess species occurrence, which maximizes the use of available resources. Increased implementation of approaches that consider detection error promote ecological advancements and conservation and management decisions that are better informed.
Student Engagement with Community
Authors: Knight‐McKenna Mary , Felten Peter , Darby Alexa
Published: March 2018

Student engagement in the local community comes with both risks and rewards. This chapter explains the cognitive, behavioral, and affective outcomes of student learning in the community, along with noting the importance of preparation and reflection.
Re: Predicting delivery of a small‐for‐gestational‐age infant and adverse perinatal outcome in women with suspected pre‐eclampsia. M. Griffin, P. T. Seed, S. Duckworth, R. North, J. Myers, L. Mackillop, N. Simpson, J. Waugh, D. Anumba, L. C. Kenny, C. W. G. Redman, A. H. Shennan and L. C. Chappell. Ultrasound Obstet Gynecol 2018; 51: 387–395.
Authors: Kingdom J. C.
Published: March 2018

Linked Comment: Ultrasound Obstet Gynecol 2018; 51: 387–395
Structural transformation and implications for future job quality
Authors: Mourelo Elva Lopez , Kühn Stefan , Milasi Santo , Yoon Sheena , Viegelahn Christian
Published: March 2018

This Chapter investigates the long‐term trends in the reallocation of employment across sectors, and assesses their implications for overall working conditions and employment arrangements. Results show that differences in working conditions are sizeable across sectors, so that employment shifts across sectors have the potential to change the quality of employment. However, improvements along this dimension hinge on the assumption that transitioning workers are able to find jobs with better working conditions, which is by no means guaranteed.
Sterically Tuned P‐Phosphanylamino Phosphaalkenes (Me3Si)2C=PN(R)PPh2 and (iPrMe2Si)2C=PN(R)PPh2
Authors: Bîrzoi Roxana M. , Lungu Daniela , Jones Peter G. , Bartsch Rainer , du Mont Wolf‐W.
Published: March 2018

Deprotonation of the aminophosphanes Ph2PN(H)R 1a–1h [R = tBu (1a), 1‐adamantyl (1b), iPr (1c), CPh3 (1d), Ph (1e), 2,4,6‐Me3C6H2 (Mes) (1f), 2,4,6‐tBu3C6H2 (Mes*) (1g), 2,6‐iPr2C6H3 (DIPP) (1h)], followed by reactions of the phosphanylamide salts Li[Ph2PNR] 2a, 2b, 2g, and 2h with the P‐chlorophosphaalkene (Me3Si)2C=PCl, and of 2a–2g with (iPrMe2Si)2C=PCl, gave the isolable P‐phosphanylamino phosphaalkenes (Me3Si)2C=PN(R)PPh2 3a, 3b, 3g, and (iPrMe2Si)2C=PN(R)PPh2 4a–4g. 31P NMR spectra, supported by X‐ray structure determinations, reveal that in compounds 2a, 2b, 3a, and 3b, with bulky N‐alkyl groups the Si2C=P–N–P skeleton is non‐planar (orthogonal conformation), whereas 3g, 3h, and 4g with bulky N‐aryl groups exhibit planar conformations of the Si2C=P–N–P skeleton. Solid 3g and 4g exhibit cisoid orientation of the planar C=P–N–C units (planar I) but in solid 3h the transoid rotamer is present (planar II). From 3g, 4d, and 4g mixtures of rotamers were detected in solution by pairs of 31P NMR patterns (3h: line broadening).
Complex Langevin simulation of a random matrix model at nonzero chemical potential
Authors: Bloch J. , Glesaaen J. , Verbaarschot J. J. M. , Zafeiropoulos S.
Published: March 2018

Abstract

In this paper we test the complex Langevin algorithm for numerical simulations of a random matrix model of QCD with a first order phase transition to a phase of finite baryon density. We observe that a naive implementation of the algorithm leads to phase quenched results, which were also derived analytically in this article. We test several fixes for the convergence issues of the algorithm, in particular the method of gauge cooling, the shifted representation, the deformation technique and reweighted complex Langevin, but only the latter method reproduces the correct analytical results in the region where the quark mass is inside the domain of the eigenvalues. In order to shed more light on the issues of the methods we also apply them to a similar random matrix model with a milder sign problem and no phase transition, and in that case gauge cooling solves the convergence problems as was shown before in the literature.
Maximally supersymmetric AdS solutions and their moduli spaces
Authors: Lüst Severin , Rüter Philipp , Louis Jan
Published: March 2018

Abstract

We study maximally supersymmetric AdSDsolutions of gauged supergravities in dimensionsD≥ 4. We show that such solutions can only exist if the gauge group after spontaneous symmetry breaking is a product of two reductive groupsHR×Hmat, whereHRis uniquely determined by the dimensionDand the number of supersymmetries$$ \mathcal{N} $$NwhileHmatis unconstrained. This resembles the structure of the global symmetry groups of the holographically dual SCFTs, whereHRis interpreted as the R-symmetry andHmatas the flavor symmetry. Moreover, we discuss possible supersymmetry preserving continuous deformations, which correspond to the conformal manifolds of the dual SCFTs. Under the assumption that the scalar manifold of the supergravity is a symmetric space we derive general group theoretical conditions on these moduli. Using these results we determine the AdS solutions of all gauged supergravities with more than 16 real supercharges. We find that almost all of them do not have supersymmetry preserving deformations with the only exception being the maximal supergravity in five dimensions with a moduli space given by SU(1,1)/U(1). Furthermore, we determine the AdS solutions of four-dimensional$$ \mathcal{N} $$N= 3 supergravities and show that they similarly do not admit supersymmetric moduli.
A Morally Permissible Moral Mistake? Reinterpreting a Thought Experiment as Proof of Concept
Authors: Emmerich Nathan , Gordjin Bert
Published: March 2018

This paper takes the philosophical notion of suberogatory acts or morally permissible moral mistakes and, via a reinterpretation of a thought experiment from the medical ethics literature, offers an initial demonstration of their relevance to the field of medical ethics. That is, at least in regards to this case, we demonstrate that the concept of morally permissible moral mistakes has a bearing on medical decision-making. We therefore suggest that these concepts may have broader importance for the discourse on medical ethics and should receive fuller consideration by those working the field. The focus of the discussion we present is on a particular thought experiment originally presented by Sulmasy and Sugarman. Their case formed the basis of an exchange about the moral equivalence of withdrawing and withholding life-saving treatment. The analysis Sulmasy and Sugarman set out is significant because, contrary to common bioethical opinion, it implies that the difference between withdrawing and withholding life-saving treatment holds, rather than lacks, moral significance. Following a brief discussion of rejoinders to Sulmasy and Sugarman’s article, we present a constructive reinterpretation of the thought experiment, one that draws on the idea of suberogatory acts or “morally permissible moral mistakes.” Our analysis, or so we suggest, accounts for the differing moral intuitions that the case prompts. However, it also calls into question the degree to which this thought experiment can be thought of as illustrating the moral (non)equivalence of withdrawing and withholding life-saving treatment. Rather, we conclude that it primarily illuminates something about the ethical parameters of healthcare when family members, particularly parents, are involved in decision-making.
Does Advertising Content Matter? Impacts of Healthy Eating and Anti-Obesity Advertising on Willingness to Pay by Consumer Body Mass Index
Authors: Wang Ruitong , Liaukonyte Jura , Kaiser Harry M.
Published: March 2018

This study examines the impacts of two types of advertising content—healthy eating and anti-obesity advertising—on the demand for healthy and unhealthy food and beverage items. We show that differentiating consumers by weight is crucial in fully understanding the effects of advertising content on food and beverage demand. We find that among overweight individuals, anti-obesity advertisements are more effective than healthy eating advertisements at reducing the demand for unhealthy items and increasing the demand for healthy items. Furthermore, the magnitude of this effect increases with BMI. We discuss possible explanations and policy implications based on our results.
Bubble dynamics in microchannels: inertial and capillary migration forces
Authors: Rivero-Rodriguez Javier , Scheid Benoit
Published: March 2018

This work focuses on the dynamics of a train of unconfined bubbles flowing in a microchannel. We investigate the transverse position of the train of bubbles, its velocity and the associated pressure drop when flowing in a microchannel, depending on the internal forces due to viscosity, inertia and capillarity. Despite the small scales of the system, the inertial migration force plays a crucial role in determining the transverse equilibrium position of the bubbles. Besides inertia and viscosity, other effects may also affect the transverse migration of bubbles, such as the Marangoni surface stresses and the surface deformability. We look at the influence of surfactants in the limit of infinite Marangoni effect, which yields a rigid bubble interface. The resulting migration force may balance external body forces, if present, such as buoyancy, centrifugal or magnetic ones. This balance not only determines the transverse position of the bubbles but, consequently, the surrounding flow structure, which can be determinant for any mass/heat transfer process involved. Finally, we look at the influence of the bubble deformation on the equilibrium position and compare it with the inertial migration force at the centred position, explaining the stable or unstable character of this position accordingly. A systematic study of the influence of the parameters, such as the bubble size, uniform body force, Reynolds and capillary numbers, has been carried out using numerical simulations based on the finite element method, solving the full steady Navier–Stokes equations and their asymptotic counterparts for the limits of small Reynolds and/or capillary numbers.
Taxonomic status of some species of Aspidostomatidae (Bryozoa, Cheilostomata) from the Oligocene and Miocene of Patagonia (Argentina)
Authors: Pérez Leandro M. , López-Gappa Juan , Griffin Miguel
Published: March 2018

The bryozoan genusAspidostomaHincks, 1881 has been regarded as the only representative of the Aspidostomatidae Jullien, 1888 in Argentina to date. Its type species,Aspidostoma giganteum(Busk, 1854), is presently distributed in the Magellanic Region (Argentina and Chile) and has been recorded in Oligocene and Miocene fossil deposits of Santa Cruz and Chubut, respectively. New material from San Julián (late Oligocene), Monte León (early Miocene), Chenque (early to middle Miocene), and Puerto Madryn (late Miocene) formations suggests, however, thatA. giganteumis not represented in the fossil record. Material from Puerto Madryn Formation previously regarded asA. giganteumis here recognized asAspidostoma roveretoinew species.Aspidostoma ortmanniCanu, 1904 is revalidated for the species from the San Julián Formation.Aspidostoma armatumnew species andAspidostoma tehuelchenew species are introduced for material from the Monte León and Chenque formations, respectively.Aspidostoma incrustansCanu, 1908, from the early Miocene, is redescribed.MelychocellaGordon and Taylor, 1999, which differs fromAspidostomain having vicarious avicularia and lacking a median ridge and a quadrangular process proximal to the opesia-orifice, is so far represented by three Paleogene species from the Chatham Islands (Southwest Pacific). The material from Monte León allowed us to transferAspidostoma flammulumCanu, 1908 toMelychocella, resulting in the new combinationMelychocella flammula(Canu, 1908).Melychocella biperforatanew species is described from the lower Miocene Monte León and Chenque formations. The presence ofMelychocellain the Neogene of Patagonia extends its geographic distribution and its temporal range.

UUID:http://zoobank.org/d84df2d8-cab2-4e74-82b8-7c67d938a58f
ON THE HYPERSTABILITY OF A PEXIDERISED -QUADRATIC FUNCTIONAL EQUATION ON SEMIGROUPS
Authors: EL-FASSI IZ-IDDINE , BRZDĘK JANUSZ
Published: March 2018

Motivated by the notion of Ulam stability, we investigate some inequalities connected with the functional equation $$\begin{eqnarray}f(xy)+f(x\unicode[STIX]{x1D70E}(y))=2f(x)+h(y),\quad x,y\in G,\end{eqnarray}$$ for functions $f$ and $h$ mapping a semigroup $(G,\cdot )$ into a commutative semigroup $(E,+)$, where the map $\unicode[STIX]{x1D70E}:G\rightarrow G$ is an endomorphism of $G$ with $\unicode[STIX]{x1D70E}(\unicode[STIX]{x1D70E}(x))=x$ for all $x\in G$. We derive from these results some characterisations of inner product spaces. We also obtain a description of solutions to the equation and hyperstability results for the $\unicode[STIX]{x1D70E}$-quadratic and $\unicode[STIX]{x1D70E}$-Drygas equations.
A REMARK ON THE TRACIAL ROKHLIN PROPERTY
Authors: ZHANG YUAN HANG
Published: March 2018

To explore the difficulties of classifying actions with the tracial Rokhlin property using K-theoretic data, we construct two $\mathbb{Z}_{2}$ actions $\unicode[STIX]{x1D6FC}_{1},\unicode[STIX]{x1D6FC}_{2}$ on a simple unital AF algebra $A$ such that $\unicode[STIX]{x1D6FC}_{1}$ has the tracial Rokhlin property and $\unicode[STIX]{x1D6FC}_{2}$ does not, while $(\unicode[STIX]{x1D6FC}_{1})_{\ast }=(\unicode[STIX]{x1D6FC}_{2})_{\ast }$, where $(\unicode[STIX]{x1D6FC}_{i})_{\ast }$ is the induced map by $\unicode[STIX]{x1D6FC}_{i}$ acting on $K_{0}(A)$ for $i=1,2$.
Apes, skulls and drums: using images to make ethnographic knowledge in imperial Germany
Authors: PETROU MARISSA H.
Published: March 2018

In this paper, I discuss the development and use of images employed by the Dresden Royal Museum for Zoology, Anthropology and Ethnography to resolve debates about how to use visual representation as a means of making ethnographic knowledge. Through experimentation with techniques of visual representation, the founding director, A.B. Meyer (1840–1911), proposed a historical, non-essentialist approach to understanding racial and cultural difference. Director Meyer's approach was inspired by the new knowledge he had gained through field research in Asia-Pacific as well as new forms of imaging that made highly detailed representations of objects possible. Through a combination of various techniques, he developed new visual methods that emphasized intimate familiarity with variations within any one ethnic group, from skull shape to material ornamentation, as integral to the new disciplines of physical and cultural anthropology. It is well known that photographs were a favoured form of visual documentation among the anthropological and ethnographic sciences at thefin de siècle. However, in the scholarly journals of the Dresden museum, photographs, drawings, tables and etchings were frequently displayed alongside one another. Meyer sought to train the reader's eye through organized arrangements that represented objects from multiple angles and at various levels of magnification. Focusing on chimpanzees, skulls and kettledrums from Asia-Pacific, I track the development of new modes of making and reading images, from zoology and physical anthropology to ethnography, to demonstrate how the museum visually historicized humankind.
Utopian biologies
Authors: Endersby Jim
Published: March 2018

In 1924, the British biologist J.B.S. Haldane acknowledged that anyone who tried to predict where science was taking us was obliged to mention H.G. Wells, since ‘[t]he very mention of the future suggests him’. Nevertheless, Haldane complained that Wells was ‘a generation behind the time’, having been raised when flying and radiotelegraphy were genuinely scientific questions, but they were now mere ‘commercial problems’, Haldane asserted, and ‘I believe that the centre of scientific interest lies in biology’. Haldane's conviction that biology was the key to the future was widely shared, and lies in the background of both these books. Helen Curry examines the early history of the dream of engineering new kinds of plants, using first X-rays, then colchicine (a chemical mutagen), and then the new sources of intense radioactivity that were created by the early nuclear reactors. By contrast, Ewa Luczak is interested in the influence of eugenics on American literature, focusing particularly on Jack London, Charlotte Perkins Gilman and George Schuyler. What unites these books (and the diverse topics they address) is new ways of imagining the future, specifically a future based in biology.
Patient experience of nasal obstruction and its clinical assessment
Authors: Nip L , Tan M , Whitcroft K L , Gupta R , Leung T S , Andrews P
Published: March 2018

Background:

The correlation between objective and subjective nasal obstruction is poor, and dissatisfaction rates after surgery for nasal obstruction are high. Accordingly, novel assessment techniques may be required. This survey aimed to determine patient experience and preferences for the measurement of nasal obstruction.

Method:

Prospective survey of rhinology patients.

Results:

Of 72 questionnaires distributed, 60 were completed (response rate of 83 per cent). Obstruction duration (more than one year) (χ2 = 13.5, p = 0.00024), but not obstruction severity, affected willingness to spend more time being assessed. Questionnaires (48 per cent) and nasal inspiratory peak flow measurement (53 per cent) are the most commonly used assessment techniques. Forty-nine per cent of participants found their assessment unhelpful in understanding their obstruction. Eighty-two per cent agreed or strongly agreed that a visual and numerical aid would help them understand their blockage.

Conclusion:

Many patients are dissatisfied with current assessment techniques; a novel device with visual or numerical results may help. Obstruction duration determines willingness to undergo longer assessment.
The Marketization of Citizenship in an Age of Restrictionism
Authors: Shachar Ayelet
Published: March 2018

In today's age of restrictionism, a growing number of countries are closing their gates of admission to most categories of would-be immigrants with one important exception. Governments increasingly seek to lure and attract “high value” migrants, especially those with access to large sums of capital. These individuals are offered golden visa programs that lead to fast-tracked naturalization in exchange for a hefty investment, in some cases without inhabiting or even setting foot in the passport-issuing country to which they now officially belong. In the U.S. context, the contrast between the “Dreamers” and “Parachuters” helps to draw out this distinction between civic ties and credit lines as competing bases for membership acquisition. Drawing attention to these seldom-discussed citizenship-for-sale practices, this essay highlights their global surge and critically evaluates the legal, normative, and distributional quandaries they raise. I further argue that purchased membership goods cannot replicate or substitute the meaningful links to a political community that make citizenship valuable and worth upholding in the first place.
China and the Future International Order(s)
Authors: Tang Shiping
Published: March 2018

In this essay I survey the key themes within China's discourse on international order, especially how China views its position and role in shaping the existing and future order. I go on to explore the possible implications of China's thinking and actions toward the existing international order. I conclude that overall, China sees no need for and hence does not seek fundamental transformation, but rather piecemeal modification of the existing order. In fact, China has been quite content with the existing order that supports globalization, despite occasional rhetoric indicating otherwise. In the near future, China will likely invest heavily in two key issue areas: (1) regionalism in East Asia and Central Asia; and (2) interregional cooperation and coordination. Perhaps unsurprisingly, China's ambitious “One Belt and One Road” initiative seeks to integrate these two issue areas.
Semi-analytical study of the Voinovs problem
Authors: KARABUT E. A. , PETROV A. G. , ZHURAVLEVA E. N.
Published: March 2018

A problem from the class of unsteady plane flows of an ideal fluid with a free boundary is considered. A conformal mapping of the exterior of a unit circle onto the region occupied by the fluid is sought. The solution is constructed in the form of power series in time or Laurent series which are analytically continued with the use of Padé approximants and change of variables of a certain special type. The free boundary shape and the pressure and velocity distributions are found. Singularities of the solution are studied.
An extended account of contract monitoring strategies as patterns of communication
Authors: SWORDS CAMERON , SABRY AMR , TOBIN-HOCHSTADT SAM
Published: March 2018

Contract systems have come to play a vital role in many aspects of software engineering. This has resulted in a wide variety of approaches to enforcing contracts—ranging from the straightforward pre-condition and post-condition checking of Eiffel to lazy, optional, and parallel enforcement strategies. Each of these approaches has its merits, but each has required ground-up development of an entire contract monitoring system. We present a unified approach to understanding this variety, while also opening the door to as-yet-undiscovered strategies. By observing that contracts are fundamentally about communication between a program and a monitor, we reframe contract checking as communication between concurrent processes. This brings out the underlying relations between widely studied enforcement strategies, including strict and lazy enforcement as well as concurrent approaches, including new contracts and strategies. We show how each of these can be embedded into a core calculus, and demonstrate a proof (via simulation) of correctness for one such encoding. Finally, we show that our approach suggests new monitoring approaches and contracts not previously expressible.
Are Schemas Passed on? A Study on the Association Between Early Maladaptive Schemas in Parents and Their Offspring and the Putative Translating Mechanisms
Authors: Sundag Johanna , Zens Christine , Ascone Leonie , Thome Susanne , Lincoln Tania M.
Published: March 2018

Background:According to Young's schema theory, Early Maladaptive Schemas (EMSs) arise due to the violation of core emotional needs during childhood. It seems likely that parents have difficulties in satisfying their children's emotional needs if they have high levels of EMSs themselves.Aims:This study investigated whether the extent of EMSs in parents is associated with the extent of EMSs in their offspring. Moreover, we tested for two putative mechanisms that account for this association: parental coping styles and parenting behaviour.Methods:Sixty dyads of parents (mother or father) and their adult children (N= 120), recruited from the general population, completed the Young Schema Questionnaire. The parents rated their schema coping styles and the children retrospectively rated the parenting of the participating parent.Results:As expected, parents' EMSs were significantly associated with EMSs in their offspring. This association was accounted for by the parental coping styleOvercompensationand the adverse parenting that the child remembered. The parental coping styleAvoidancedid not account for the association.Conclusions:This study provides preliminary evidence for the notion that EMSs are passed on from one generation to the next via parental coping and parenting. Our findings thus support the assumption of schema theory that EMSs are connected to the family environment in terms of adverse parenting. If further confirmed, this has relevant implications for family-based interventions.
The Affordable Care Act as retiree health insurance: implications for retirement and Social Security claiming
Authors: GUSTMAN ALAN L. , STEINMEIER THOMAS L. , TABATABAI NAHID
Published: March 2018

This paper investigates the effects of the Affordable Care Act (ACA) on retirement. The first part of the paper is a difference-in-difference analysis of changes in retirement (and retirement expectations) before and after adoption of the ACA. We find no statistically significant evidence that ACA increased the propensity to retire or changed retirement expectations. The second part of the analysis is based on a structural retirement model. For those age 50 at the time ACA was introduced, the overall reduction in full-time work over the age span 54–65 is simulated to be about 0.1 percentage points. Data are from the Health and Retirement Study.
Explaining State Violence in the Guatemalan Civil War: Rebel Threat and Counterinsurgency
Authors: Kubota Yuichi
Published: March 2018

Literature on the Guatemalan Civil War has debated whether or not state violence was triggered by rebel activities. Did the government respond to each insurrection caused by the rebels, or did it blindly target regions where antigovernment antipathy and movements had historically prevailed? Because state violence was extensive during the civil war period, the dynamism of the war could have been the reason for its occurrence. Relying on the threat-response model of state violence, this article argues that human rights violations occurred when the government perceived a rebel threat that would have seriously degraded its capability in future counterinsurgencies. The article employs propensity score matching to address the problem of confounding in empirical analysis, and reveals that rebel attacks, particularly those targeting security apparatus and resulting in human injury, increased the likelihood of state violence in the Guatemalan Civil War.
Remarks of Gaia DR1 magnitude using ground-based optical monitoring of QSOs
Authors: Damljanović Goran , Taris François , Andrei Alexandre
Published: March 2018

Since September 2016, the first release (DR1) of the Gaia catalogue was appeared. The optical Gaia positions of sources will be linked to the ICRF (VLBI radio positions of mostly quasars, QSOs). For high accurate link we need to investigate variations of optical flux of QSOs via their magnitude variations using data of ground-based telescopes. To do that, from 2013 we observed 47 QSOs and other sources; nine optical telescopes were used for that monitoring. To increase the total number of objects for the link, after a first set of 70 objects (Bourda et al. 2008), Bourda et al. (2011) established a second set of 47 objects. It is necessary to investigate the photometry and morphology of these objects. We collected ground-based data of QSOs (B, V and R mag) and compared with G mag of Gaia DR1; some results are presented here.
GIER: A Danish computer from 1961 with a role in the modern revolution of astronomy - II
Authors: Høg Erik
Published: March 2018

A Danish computer, GIER, from 1961 played a vital role in the development of a new method for astrometric measurement. This method, photon counting astrometry, ultimately led to two satellites with a significant role in the modern revolution of astronomy. A GIER was installed at the Hamburg Observatory in 1964 where it was used to implement the entirely new method for the measurement of stellar positions by means of a meridian circle, at that time the fundamental instrument of astrometry. An expedition to Perth in Western Australia with the instrument and the computer was a success. This method was also implemented in space in the first ever astrometric satellite Hipparcos launched by ESA in 1989. The Hipparcos results published in 1997 revolutionized astrometry with an impact in all branches of astronomy from the solar system and stellar structure to cosmic distances and the dynamics of the Milky Way. In turn, the results paved the way for a successor, the one million times more powerful Gaia astrometry satellite launched by ESA in 2013. Preparations for a Gaia successor in twenty years are making progress.
GaiaNIR – A future all-sky astrometry mission
Authors: Hobbs David , Høg Erik
Published: March 2018

With the launch of Gaia in December 2013, Europe entered a new era of space astrometry following in the footsteps of the very successful Hipparcos mission. A weakness of Gaia is that it only operates at optical wavelengths. However, much of the Galactic centre and the spiral arm regions are obscured by interstellar extinction. An obvious improvement on Gaia is to include the Near-Infra-Red (NIR) which requires the use of new types of detectors. Additionally, to scan the entire sky and measure global absolute parallaxes the spacecraft must have a constant rotation resulting in a moving image that must be compensated for by, for example, operating the detectors in Time Delayed Integration (TDI) mode. If these technical issues can be solved a new Gaia-like mission separated by a 20 year interval would give; 1) NIR all-sky astrometry and photometry to penetrate the obscured regions and to observe intrinsically red objects with almost diffraction limited resolution; 2) improved proper motions with fourteen times smaller errors than from Gaia alone opening up new science cases, such as long period exoplanets and accurate halo measurements; 3) allow the slowly degrading accuracy of the Gaia reference frame, which will be the basis for future astronomical measurements, to be reset.
OB stars towards NGC 6357 and NGC 6334
Authors: Russeil Delphine
Published: March 2018

The star forming regions NGC6334 and NGC6357 are amid the most active star-forming complexes of our Galaxy where massive star formation is occuring. Both complexes gather several HII regions but they exhibit different aspects: NGC6334 is characterised by a dense molecular ridge where recent massive star formation is obvious while NGC6357 is dominated by the action of the stellar cluster Pismis 24 which have shaped a large cavity. To understand and compare the formation of massive stars in these two regions requires to precise the distance and characterise the proper motions of the O to B3 stellar population in these regions.
A new method for orbit determination on the Gaia SB1s
Authors: Xiaoli Wang
Published: March 2018

An iterative method to determine the self-consistent orbital solutions of single-lined spectroscopic binaries (SB1s) along with compatible physical properties of component stars via a simultaneous fit including both the Hipparcos Intermediate Astrometric Data (HIAD) and radial velocity data is introduced in this work. For the method, a stellar evolutionary model is used to distribute the total mass and luminosity to the primary and the secondary and update the ratio of the semimajor axes of the photocenter to the primary orbits. Once the Gaia Intermediate Astrometric Data (GIAD) are released, the method can be applied to study the Gaia SB1s and give self-consistent orbital solutions and compatible physical properties of component stars.
Astrometry with A-Track Using Gaia DR1 Catalogue
Authors: Kılıç Yücel , Erece Orhan , Kaplan Murat
Published: March 2018

In this work, we built all sky index files from Gaia DR1 catalogue for the high-precision astrometric field solution and the precise WCS coordinates of the moving objects. For this, we used build-astrometry-index program as a part of astrometry.net code suit. Additionally, we added astrometry.net's WCS solution tool to our previously developed software which is a fast and robust pipeline for detecting moving objects such as asteroids and comets in sequential FITS images, called A-Track. Moreover, MPC module was added to A-Track. This module is linked to an asteroid database to name the found objects and prepare the MPC file to report the results. After these innovations, we tested a new version of the A-Track code on photometrical data taken by the SI-1100 CCD with 1-meter telescope at TÜBİTAK National Observatory, Antalya. The pipeline can be used to analyse large data archives or daily sequential data. The code is hosted on GitHub under the GNU GPL v3 license.
Mathematical Assessment of Physical and Chemical Processes from the Middle B to the Early F Type Main Sequence Stars
Authors: Yüce Kutluay , Adelman Saul J.
Published: March 2018

The middle B to the early F Main Sequence stars have some of the most quiet stellar atmospheres. In this part of the HR diagram we find stars with atmospheres in radiative equilibrium. They lack the convective circulations of the middle F and cooler stars and the massive stellar winds of hotter stars. When stars of different mass evolve off the Main Sequence in this part of the HR Diagram their evolutionary paths do not cross initially. Thus stars with the same effective temperature and surface gravity have the same luminosity and mass. By comparing their elemental abundances, we might be able to identify physical processes which cause any differences in their abundances. Here we begin with stars whose effective temperatures and surface gravities are similar, and which have been analyzed by us using spectra obtained from the Dominion Astrophysical Observatory (DAO). Improvements in our knowledge of the energy distributions of stars (for example via GAIA measurements) should lead to improved estimates of stellar effective temperatures and surface gravities.
Mapping young stellar populations towards Orion with Gaia DR1
Authors: Zari Eleonora , Brown Anthony G. A.
Published: March 2018

OB associations are prime sites for the study of star formation processes and of the interaction between young massive stars with the interstellar medium. Furthermore, the kinematics and structure of the nearest OB associations provide detailed insight into the properties and origin of the Gould Belt. In this context, the Orion complex has been extensively studied. However, the spatial distribution of the stellar population is still uncertain: in particular, the distances and ages of the various sub-groups composing the Orion OB association, and their connection to the surrounding interstellar medium, are not well determined. We used the first Gaia data release to characterize the stellar population in Orion, with the goal to obtain new distance and age estimates of the numerous stellar groups composing the Orion OB association. We found evidence of the existence of a young and rich population spread over the entire region, loosely clustered around some known groups. This newly discovered population of young stars provides a fresh view of the star formation history of the Orion region.
Preliminary Results of Low Dispersion Asteroid Spectroscopy Survey at NAO Rozhen
Authors: Bebekovska Elena Vchkova , Borisov Galin , Donchev Zahary , Apostolovska Gordana
Published: March 2018

We are presenting the first results of low dispersion spectroscopic observation of asteroids at Bulgarian National Astronomical Observatory Rozhen. Asteroids with unclassified spectra and brighter than 15 magnitude have been chosen. Besides just presenting the asteroid reflectance, classification according to Bus S. J. et al. (2012) has been done. The asteroid spectra of 590 Tomyris, 703 Noemi, 1596 Itzigsohn and 1826 Miller are presented together with standard spectra corresponding to the three best matches given by the public software tool M4AST (Popescu M. et al. (2012)). Our aim is to participate in the coordinated program of asteroids spectroscopy complementary to the observations of Gaia.
Hypervelocity star candidates in Gaia DR1/TGAS
Authors: Marchetti T. , Rossi E. M. , Kordopatis G. , Brown A. G. A. , Rimoldi A. , Starkenburg E. , Youakim K. , Ashley R.
Published: March 2018

Hypervelocity stars (HVSs) are characterized by a total velocity in excess of the Galactic escape speed, and with trajectories consistent with coming from the Galactic Centre. We apply a novel data mining routine, an artificial neural network, to discover HVSs in the TGAS subset of the first data release of the Gaia satellite, using only the astrometry of the stars. We find 80 stars with a predicted probability >90% of being HVSs, and we retrieved radial velocities for 47 of those. We discover 14 objects with a total velocity in the Galactic rest frame >400 km s−1, and 5 of these have a probability >50% of being unbound from the Milky Way. Tracing back orbits in different Galactic potentials, we discover 1 HVS candidate, 5 bound HVS candidates, and 5 runaway star candidates with remarkably high velocities, between 400 and 780 km s−1. We wait for future Gaia releases to confirm the goodness of our sample and to increase the number of HVS candidates.
Can we detect Galactic spiral arms? 3D dust distribution in the Milky Way
Authors: Rezaei Kh. Sara , Bailer-Jones Coryn A. L. , Fouesneau Morgan , Hanson Richard
Published: March 2018

We present a model to map the 3D distribution of dust in the Milky Way. Although dust is just a tiny fraction of what comprises the Galaxy, it plays an important role in various processes. In recent years various maps of dust extinction have been produced, but we still lack a good knowledge of the dust distribution. Our presented approach leverages line-of-sight extinctions towards stars in the Galaxy at measured distances. Since extinction is proportional to the integral of the dust density towards a given star, it is possible to reconstruct the 3D distribution of dust by combining many lines-of-sight in a model accounting for the spatial correlation of the dust. Such a technique can be used to infer the most probable 3D distribution of dust in the Galaxy even in regions which have not been observed. This contribution provides one of the first maps which does not show the “fingers of God” effect. Furthermore, we show that expected high precision measurements of distances and extinctions offer the possibility of mapping the spiral arms in the Galaxy.
Astrometry for New Reductions: The ANR method
Authors: Robert Vincent , Le Poncin-Lafitte Christophe
Published: March 2018

Accurate positional measurements of planets and satellites are used to improve our knowledge of their orbits and dynamics, and to infer the accuracy of the planet and satellite ephemerides. With the arrival of the Gaia-DR1 reference star catalog and its complete release afterward, the methods for ground-based astrometry become outdated in terms of their formal accuracy compared to the catalog's which is used. Systematic and zonal errors of the reference stars are eliminated, and the astrometric process now dominates in the error budget.

We present a set of algorithms for computing the apparent directions of planets, satellites and stars on any date to micro-arcsecond precision. The expressions are consistent with the ICRS reference system, and define the transformation between theoretical reference data, and ground-based astrometric observables.
Using ground based data as a precursor for Gaia in getting proper motions of satellites
Authors: Fritz Tobias K. , Linden Sean T. , Zivick Paul , Kallivayalil Nitya , Bovy Jo
Published: March 2018

We present our effort to measure the proper motions of satellites in the halo of the Milky Way with mainly ground based telescopes as a precursor on what is possible with Gaia. For our first study, we used wide field optical data from the LBT combined with a first epoch of SDSS observations, on the globular cluster Palomar 5 (Pal 5). Since Pal 5 is associated with a tidal stream it is very useful to constrain the shape of the potential of the Milky Way. The motion and other properties of the Pal 5 system constrain the inner halo of the Milky Way to be rather spherical. Further, we combined adaptive optics and HST to get an absolute proper motion of the globular cluster Pyxis. Using the proper motion and the line-of-sight velocity we find that the orbit of Pyxis is rather eccentric with its apocenter at more than 100 kpc and its pericenter at about 30 kpc. The dynamics excludes an association with the ATLAS stream, the Magellanic clouds, and all satellites of the Milky Way at least down to the mass of Leo II. However, the properties of Pyxis, like metallicity and age, point to an origin from a dwarf of at least the mass of Leo II. We therefore propose that Pyxis originated from an unknown relatively massive dwarf galaxy, which is likely today fully disrupted. Assuming that Pyxis is bound to the Milky Way we derive a 68% lower limit on the mass of the Milky Way of 9.5 × 1011 M⊙.
Galactic Surveys in the Gaia Era
Authors: Wyse Rosemary F. G.
Published: March 2018

The final astrometric data from the Gaia mission will transform our view of the stellar content of the Galaxy, particularly when complemented with spectroscopic surveys providing stellar parameters, line-of-sight kinematics and elemental abundances. Analyses with Gaia DR1 are already demonstrating the insight gained and the promise of what is to come with future Gaia releases. I present a brief overview of results and puzzles from recent Galactic Archaeology surveys for context, focusing on the Galactic discs.
Gaia: from proposal to GDR1
Authors: Gilmore Gerard
Published: March 2018

In this concluding article I recall the early history of the Gaia mission, showing that the original science case and expectations of wide community interest in Gaia data have been met. The quarter-century long partnership involving some 1,000 scientists, engineers and managers in industry and academia is delivering a large, high-quality and unique data set which will underpin astrophysics across many sub-fields for years to come.
Exploring the Solar System using stellar occultations
Authors: Sicardy Bruno
Published: March 2018

Stellar occultations by solar system objects allow kilometric accuracy, permit the detection of tenuous atmospheres (at nbar level), and the discovery of rings. The main limitation was the prediction accuracy, typically 40 mas, corresponding to about 1,000 km projected at the body. This lead to large time dedicated to astrometry, tedious logistical issues, and more often than not, mere miss of the event. The Gaia catalog, with sub-mas accuracy, hugely improves both the star positions, resulting in achievable accuracies of about 1 mas for the shadow track on Earth. This permits much more carefully planned campaigns, with success rate approaching 100%, weather permitting. Scientific perspectives are presented, e.g. central flashes caused by Plutos atmosphere revealing hazes and winds near its surface, grazing occultations showing topographic features, occultations by Chariklos rings unveiling dynamical features such as proper mode “breathing”.