bluuebunny/crossref_metadata_2025 huggingface dataset:
Gender Gap in Academic Achievement in Brunei Tertiary Education: Qualitative Perspective
Authors: Metussin Halimaturradiah
Published: July 2017

This study explores the potential factors causing a gender gap in academic achievement in the higher learning institutions of Brunei using in-depth interviews. Given that the gender gap is a worldwide phenomenon and problem in many educational settings, this study investigates the reasons for its persistence and how it can be resolved in the Brunei context. The findings of the study indicate that: 1) there are gender similarities in practices of good academic performance at school; 2) teaching methods and school facilities and environment may affect students’ academic performance; 3) problems or challenges faced in academic performance or achievement at school; and 4) early entry to workplace. A mixed-methods research is recommended to gain additional insights into the problem and its solutions.
Adolescents and the Challenges in their Motivation
Authors: Çelçima Denis
Published: July 2017

The study has the main object the adolescents and their academic achievements. It aims the determining of the motivation importance (in achievement and the relationship that exist between the dimensions of the internal motivation and the external one. [This instrument is used by the authors: Robert J. Vallerand, Luc G. Pelletier, Marc R. Blais: Nathalie M. Birriere, Caroline B. Senecak; Evelyne F. Vallieres, 1989; 1992]. Self - esteem and also the role of public and private awareness, is established in adolescence, when still in the transitional period the free space facing violated in psychological impact, which require bold initiatives in the field of education.
Ecotourism in Nepal
Authors: KC Anup
Published: July 2017

Ecotourism gives priority to ecological resource integrity, environmental conservation, community development and economic development by maintaining low-impact and non-consumptive use of local resources. There are different forms of ecotourism developed worldwide as community based ecotourism, ecosystem ecotourism, cultural ecotourism, nature based ecosystem, protected area ecotourism and rural ecotourism. It focuses on meeting three concurrent goals of biodiversity conservation, poverty reduction and business viability using sustainable principles and practices. In sustainable ecotourism, local government officials, local communities, NGOs, private sector and management committee had a great role for tourism development and maintaining healthy cooperation and coordination. Ecotourism had more beneficial impacts compared to adverse impacts on the environment, society and culture. It emphasizes the protection of natural resources, biological diversity and sustainability of resource. It increases mobility of people, social stability and harmony; strengthen traditional culture, hospitality and folkway; and decreases political conflicts. Economic benefits from ecotourism include direct employment in hotels, lodges, tourist restaurants, and tourist chauff euring. It is an integral part of the master development strategy of a developing nation. In Nepal, ecotourism helps to enhance forest cover, flora, fauna, greenery, alternative energy sources, natural resource, biodiversity and other environmental benefits. It had helped in controlling antisocial activities, conserving religious and cultural heritage, maintaining peace and prosperity and increase in cooperation of people with religious beliefs and religious tolerance. It had a great role in poverty alleviation, rural development, agricultural transformation, community enrichment and social empowerment of women in Nepal. In the early stage of ecotourism development, it is difficult to have adequate private agencies and local people involved in delivering lodging, fooding, tour management and tourism activities during peak visitation season. There is need of training on nature guiding, cooking, sustainable use of tourism resources, proper handling of tourism demands, expertise in park management and finance management.THE GAZEJOURNAL OF TOURISM AND HOSPITALITYVol. 8 No.1 Year 2017, page: 1-19
Choice Set Formation Behavior in Selecting Travel Routes: Application of an Interactive Online Survey Platform
Authors: Shakeel Kiran , Rashidi Taha Hossein , Waller Travis S.
Published: July 2017

One of the major challenges associated with the analysis of route choice modeling is the formulation of the choice set of alternatives that may allow a relatively accurate prediction of demand for travel routes. The subset of route alternatives in the choice set should be relevant and feasible and include the attributes considered most by travelers when they choose a route. This research investigated the role and significance of route choice set formations with a focus on the perspectives of the modeler and of travelers. Revealed preference data were collected from Sydney, Australia, residents about their choice of route for their most recent commuting trip. The survey tool was programmed to use the Google Maps application programming interfaces to collect the route choice information, including the selected route and the set of routes that were considered. Three discrete choice models were used to investigate the traveler’s inclination toward certain attributes of routes, considering both car and public transit routes with the master choice set. The effect of possible bias generated because of the formation of route choice from the perspective of the modeler was also analyzed and presented with the results. The results show the intuitive signs of various attributes, with travel time being the significant factor for route choice. The difference between the choice sets considered by the traveler and by the modeler also suggests that those considered by the modeler possess enough variation to offer the possibility of better capturing important factors affecting route choice behavior.
Transportation Planning to Accommodate Needs of Wind Energy Projects
Authors: Astroza Sebastian , Patil Priyadarshan N. , Smith Katherine I. , Bhat Chandra R.
Published: July 2017

There is an upward trend in wind energy production in Texas and a growing need to transport wind turbine components in that state. This paper proposes a methodology and an associated operational planning tool that can be used to develop optimal route plans for the transportation of wind turbine components on Texas roadways. The paper also recommends transportation infrastructure maintenance and improvement strategies, as well as more general multisector infrastructure improvements that will be needed to respond to the predicted growth of wind energy over time. Specifically, researchers predicted the amount of energy that will be installed in Texas from 2015 to 2025 and used the new planning tool, along with detailed knowledge of the wind energy production industry and the related supply chain, to find optimal routes for wind turbine components (minimizing both potential for road damage and driver delay). A methodology in which the planning tool is used for the analysis of several what-if scenarios is also proposed. Although the planning tool and the associated methodology were developed for Texas, they can be generalized to any other state after the underlying databases are updated.
Large-Scale Application of a Combined Destination and Mode Choice Model Estimated with Mixed Stated and Revealed Preference Data
Authors: Heilig Michael , Mallig Nicolai , Hilgert Tim , Kagerbauer Martin , Vortisch Peter
Published: July 2017

The diffusion of new modes of transportation, such as carsharing and electric vehicles, makes it necessary to consider them along with traditional modes in travel demand modeling. However, there are two main challenges for transportation modelers. First, the new modes’ low share of usage leads to a lack of reliable revealed preference data for model estimation. Stated preference survey data are a promising and well-established approach to close this gap. Second, the state-of-the-art model approaches are sometimes stretched to their limits in large-scale applications. This research developed a combined destination and mode choice model to consider these new modes in the agent-based travel demand model mobiTopp. Mixed revealed and stated preference data were used, and new modes (carsharing, bikesharing, and electric bicycles) were added to the mode choice set. This paper presents both challenges of the modeling process, mainly caused by large-scale application, and the results of the new combined model, which are as good as those of the former sequential model although it also takes the new modes into consideration.
Sensitivity-Based Linear Approximation Method to Estimate Time-Dependent Origin–Destination Demand in Congested Networks
Authors: Shafiei Sajjad , Saberi Meead , Zockaie Ali , Sarvi Majid
Published: July 2017

This paper presents a bi-level optimization problem to estimate offline time-dependent origin–destination (time-dependent O-D) demand on the basis of link flows and historical O-D matrices. The upper-level problem aimed to minimize the summation of errors in both traffic counts and O-D demand. Conventionally, O-D flows are linearly mapped to link flows with the assignment matrix proportions obtained from the dynamic traffic assignment, which is typically formulated as the lower-level problem. However, the linear relationship may be invalid when congestion builds up in the network, and a nonlinear relation between O-D flows and link flows may result. The nonlinearity may lead to a converged solution that is far from the global optimum. An accurate solution should be able to relax the linear assumption and to consider the effect of other O-D flows on the links’ traffic volumes. In this study, a solution method that relied on the sensitivity of assignment proportions to O-D flows was proposed and applied; it required a number of further assignments. To overcome the extra computational requirement, a heuristic method to exclude the extra assignments and to improve the performance of the solution was proposed. The proposed algorithm was applied to multiple networks of varying sizes and congestion levels. The results demonstrated the efficiency of the proposed method for congested networks with less computation time.
Exploratory Analysis of the Activity Time-Use Frontier and Its Effect on Episodic Well-Being: Data from the Disability and Use of Time Survey
Authors: Ravulaparthy Srinath K. , Konduri Karthik C. , Goulias Konstadinos G.
Published: July 2017

The role of time (as a constrained resource) in terms of budgets and expenditures is of great importance in travel behavior analysis within the context of daily activity engagement choices, emotional well-being, and quality of life. This research investigated the behavioral links between activity time budgets and episodic well-being measures in a two-stage process, using data from the 2009 Disability and Use of Time Survey. First, with the use of the episodic-level data, time budgets were formulated with the use of a stochastic frontier modeling approach. The technical inefficiency measure that represented the degree to which an individual expended his or her time (or an upper bound of the time budget) in activity engagement was also derived. Second, with the use of this measure of technical inefficiency, the effects on reported individuals’ episodic well-being measures were further investigated. The indicators of well-being—happiness, calmness, frustration, sadness, worry, tiredness, and pain—were analyzed with a multivariate ordered probit modeling framework. The models were estimated by controlling for a broad array of covariates related to sociodemographics, activity, and travel characteristics, along with the social contexts of companionship and altruism and global well-being indicators. Empirical results suggested that individuals experienced varying levels of positive and negative emotions from their daily activity time-use patterns, in both efficient and inefficient episodes. Productive episodes (e.g., working and volunteering) with higher time budgets (or inefficiencies) increased the likelihood of individuals experiencing higher levels of negative emotions. The model findings also revealed that high-income households and individuals younger than 65 years old with inefficient time-use patterns exhibited lower levels of happiness and calmness.
Clinical Herpes Zoster in Antarctica as a Model for Spaceflight
Authors: Reyes David P. , Brinley Alaina A. , Blue Rebecca S. , Gruschkus Stephen K. , Allen Andrew T. , Parazynski Scott E.
Published: July 2017

INTRODUCTION: Antarctica is a useful analog for spaceflight, as both environments are remote, isolated, and with limited resources. While previous studies have demonstrated increased asymptomatic viral shedding in both the Antarctic and spaceflight environments, clinical manifestations
of reactivated viral disease have been less frequently identified. We sought to identify the incidence of clinical herpes zoster from viral reactivation in the Antarctic winter-over population.METHODS: Medical records from the 2014 winter season were reviewed for the incidence of
zoster in U.S. Antarctic personnel and then compared to the age-matched U.S. population.RESULTS: Five cases of clinical herpes zoster occurred in the Antarctic Station population of 204 persons, for an incidence of 33.3 per 1000 person-years vs. 3.2 per 1000 person-years in the
general population. Four cases were in persons under age 40, yielding an incidence of 106.7 per 1000 person-years in persons ages 30–39 compared to an incidence of 2.0 per 1000 person-years in the same U.S. age group.DISCUSSION: Immune suppression due to the stressful Antarctic
environment may have contributed to the increased incidence of herpes zoster in U.S. Antarctic personnel during the winter of 2014. Working and living in isolated, confined, and extreme environments can cause immune suppression, reactivating latent viruses and increasing viral shedding and
symptomatic disease. Such changes have been observed in other austere environments, including spaceflight, suggesting that clinical manifestations of viral reactivation may be seen in future spaceflight.Reyes DP, Brinley AA, Blue RS, Gruschkus SK, Allen AT, Parazynski SE. Clinical herpes zoster in Antarctica as a model for spaceflight. Aerosp Med Hum Perform. 2017; 88(8):784–788.
Human Performance Time Model of Spacecraft Control Panel Operation in Simulated Microgravity
Authors: Cao Shi , Zhang Yijing , Guo Yunhuan , Chen Shanguang
Published: July 2017

BACKGROUND: Human performance modeling plays an important role in the design and management of human spaceflight missions. Previous studies reported that manual control task time increased in microgravity conditions. The current study aimed to find a modeling method that can
quantify and predict the task time of spacecraft control panel operation in the simulated microgravity condition.METHODS: We proposed the application of a predetermined elemental task method together with an information processing time model to quantify both physical motion time
and cognitive time. The time increment due to microgravity was hypothesized to be proportional to physical motion time. The total task time in the microgravity condition could be calculated as the model time from the normal ground condition plus the predicted time increment. Human data were
collected from an experiment asking participants to perform six emergency operating procedure tasks in both normal ground and simulated microgravity conditions.RESULTS: The proposed method resulted in good fitness to human data in both conditions, as shown by both regression fitness
(R2 values = 0.99) and modeling error measures (root mean square error ≤ 3.3 s; mean absolute percentage error ≤ 16.1%).CONCLUSIONS: Although the method has its limitations, the current findings suggest that it has value in aerospace human factors and ergonomics
applications.Cao S, Zhang Y, Guo Y, Chen S. Human performance time model of spacecraft control panel operation in simulated microgravity. Aerosp Med Hum Perform. 2017; 88(8):743–751.
Flight Performance During Exposure to Acute Hypobaric Hypoxia
Authors: Steinman Yuval , van den Oord Marieke H. A. H. , Frings-Dresen Monique H. W. , Sluiter Judith K.
Published: July 2017

INTRODUCTION: The purpose of the present study was to examine the influence of hypobaric hypoxia (HH) on a pilot’s flight performance during exposure to simulated altitudes of 91, 3048, and 4572 m (300, 10,000, and 15,000 ft) and to monitor the pilot’s physiological
reactions.METHOD: In a single-blinded counter-balanced design, 12 male pilots were exposed to HH while flying in a flight simulator that had been placed in a hypobaric chamber. Flight performance of the pilots, pilot’s alertness level, Spo2, heart rate
(HR), minute ventilation (VE), and breathing frequency (BF) were measured.RESULTS: A significant difference was found in Flight Profile Accuracy (FPA) between the three altitudes. Post hoc analysis showed no significant difference in performance between 91 m and 3048
m. A trend was observed at 4572 m, suggesting a decrease in flight performance at that altitude. Significantly lower alertness levels were observed at the start of the flight at 4572 m compared to 91 m, and at the end of the flight at 4572 m compared to the start at that altitude. Spo2
and BF decreased, and HR increased significantly with altitude.DISCUSSION: The present study did not provide decisive evidence for a decrease in flight performance during exposure to simulated altitudes of 3048 and 4572 m. However, large interindividual variation in pilots’
flight performance combined with a gradual decrease in alertness levels observed in the present study puts into question the ability of pilots to safely fly an aircraft while exposed to these altitudes without supplemental oxygen.Steinman Y, van den Oord MHAH, Frings-Dresen MHW, Sluiter
JK. Flight performance during exposure to acute hypobaric hypoxia. Aerosp Med Hum Perform. 2017; 88(8):760–767.
Sustained Accelerated Idioventricular Rhythm in a Centrifuge-Simulated Suborbital Spaceflight
Authors: Suresh Rahul , Blue Rebecca S. , Mathers Charles , Castleberry Tarah L. , Vanderploeg James M.
Published: July 2017

INTRODUCTION: Hypergravitational exposures during human centrifugation are known to provoke dysrhythmias, including sinus dysrhythmias/tachycardias, premature atrial/ventricular contractions, and even atrial fibrillations or flutter patterns. However, events are generally short-lived
and resolve rapidly after cessation of acceleration. This case report describes a prolonged ectopic ventricular rhythm in response to high G exposure.CASE REPORT: A previously healthy 30-yr-old man voluntarily participated in centrifuge trials as a part of a larger study, experiencing
a total of 7 centrifuge runs over 48 h. Day 1 consisted of two +Gz runs (peak +3.5 Gz, run 2) and two +Gx runs (peak +6.0 Gx, run 4). Day 2 consisted of three runs approximating suborbital spaceflight profiles (combined +Gx and +Gz).
Hemodynamic data collected included blood pressure, heart rate, and continuous three-lead electrocardiogram. Following the final acceleration exposure of the last Day 2 run (peak +4.5 Gx and +4.0 Gz combined, resultant +6.0 G), during a period of idle resting centrifuge
activity (resultant vector +1.4 G), the subject demonstrated a marked change in his three-lead electrocardiogram from normal sinus rhythm to a wide-complex ectopic ventricular rhythm at a rate of 91–95 bpm, consistent with an accelerated idioventricular rhythm (AIVR). This rhythm was
sustained for 2 m, 24 s before reversion to normal sinus. The subject reported no adverse symptoms during this time.DISCUSSION: While prolonged, the dysrhythmia was asymptomatic and self-limited. AIVR is likely a physiological response to acceleration and can be managed conservatively.
Vigilance is needed to ensure that AIVR is correctly distinguished from other, malignant rhythms to avoid inappropriate treatment and negative operational impacts.Suresh R, Blue RS, Mathers C, Castleberry TL, Vanderploeg JM. Sustained accelerated idioventricular rhythm in a centrifuge-simulated suborbital spaceflight. Aerosp Med Hum Perform. 2017; 88(8):789–793.
The Compatibility of South African Anti-Dumping Laws with WTO Disciplines
Authors: Khanderia Saloni
Published: July 2017

This article evaluates the compatibility of South African laws on anti-dumping with the WTO disciplines set forth in the Anti-Dumping Agreement. It analyses the provisions of the International Trade Administration Act 2002 and the Anti-Dumping Regulations 2005 to examine whether South Africa has been adhering to its WTO obligations. The South African law on this subject is largely incompatible with its WTO counterpart in matters of, inter alia, the calculation of the constructed export price, the determination of material injury and a causal relationship, the imposition of provisional and definitive anti-dumping duties and the procedure for review. This has in turn resulted in strained relationships between South Africa and the other members of the international community in regard to the procedures adopted during anti-dumping investigations.
The African Court with a Criminal Jurisdiction and the ICC: A Case for Overlapping Jurisdiction?
Authors: Abebe Zekarias Beshah
Published: July 2017

One of the issues that the current proliferation of international courts and jurisdictions raised in the international legal order is overlapping jurisdiction. On 27 June 2014, the Assembly of the African Union adopted a protocol on the Amendments to the Protocol on the Statute of the African Court of Justice and Human Rights which extends the jurisdiction of the court to cover international crimes. The decision of the AU to clothe the African court with a criminal jurisdiction has brought, once again, the issue of overlapping jurisdiction to the surface. This article is an attempt to answer the questions: to what extent does the criminal jurisdiction of the African court overlap with the jurisdiction of the ICC, and is the issue of overlapping jurisdiction a common occurrence or an imminent concern? Taking the crimes under the jurisdiction of the courts and the fact that large numbers of African states are state parties to the ICC into consideration, many tend to argue that overlapping jurisdiction is inevitable and is likely to cause friction for the primacy of jurisdiction. However, this article argues that a close scrutiny of the substantive and territorial jurisdiction of the ICC and the African Court suggests that the issue of overlapping jurisdiction is both rare and of remote concern.
Chronic Disease Registries – Trends and Challenges
Authors: Fored Michael , Schüz Joachim
Published: July 2017

Background: This accompanying editorial is an introduction to the focus theme of “chronic disease registries - trends and challenges”.

Methods: A call for papers was announced on the website of Methods of Information in Medicine in April 2016 with submission deadline in September 2016. A peer review process was established to select the papers for the focus theme, managed by two guest editors.

Results: Three papers were selected to be included in the focus theme. Topics range from contributions to patient care through implementation of clinical decision support functionality in clinical registries; analysing similar-purposed acute coronary syndrome registries of two countries and their registry-to- SNOMED CT maps; and data extraction for speciality population registries from electronic health record data rather than manual abstraction.

Conclusions: The focus theme gives insight into new developments related to disease registration. This applies to technical challenges such as data linkage and data as well as data structure abstraction, but also the utilisation for clinical decision making.
Sustainable synthesis of 3-substituted phthalides via a catalytic one-pot cascade strategy from 2-formylbenzoic acid with β-keto acids in glycerol
Authors: Jia Lina , Han Fuzhong
Published: July 2017

Background: Phthalides are privileged constituents of numerous pharmaceuticals, natural products and agrochemicals and exhibit several biological and therapeutic activities. Therefore, the development of new, facile, and sustainable strategies for the construction of these moieties is highly desired.

Results: A broad substrate scope for β-keto acids was found to be strongly compatible with this catalytic process, affording a wide variety of 3-substituted phthalides in good to excellent yields.

Conclusion: A concise and efficient synthesis strategy of 3-substituted phthalides from 2-formylbenzoic acid and β-keto acids via a catalytic one-pot cascade reaction in glycerol has been accomplished.
Comparing the Diagnostic Criteria of Metabolic Syndrome in Schoolchildren: Cross-sectional Study
Authors: Cirino Ingred Pereira , Silva Leylla Lays Alves e , Oliveira Karollayny De Macêdo , Melo Júnior Eugênio Barbosa de , Oliveira Edina Araújo Rodrigues , Lima Luisa Helena de Oliveira
Published: July 2017

Title: Comparing the diagnostic criteria of metabolic syndrome in schoolchildren: a cross-sectional study.

Introduction: The Metabolic Syndrome has been highlighted by being the result of the meeting of several cardiovascular risk factors. However, there is still no consensus for the determination of MS in children and adolescents, since the diagnostic criteria and its cut-off points considered at risk are not established and, depending on the criteria used, the prevalence of MS found in the literature may vary.

Objective: To compare the diagnostic criteria for metabolic syndrome in adolescents in the private school system.

Method: This is a cross-sectional study of 325 adolescents from private schools in the urban area of a city in northeastern Brazil. The analysis was performed through the descriptive statistics, and the verification of the agreement between the results was given by the calculation of the Kappa index. The study was approved by the Ethics Committee (opinion 352.372).

Results: In only 7 adolescents, the diagnosis was like the three definitions of metabolic syndrome. Regarding the number of components of metabolic syndrome, a large percentage of adolescents presented 02 or more altered parameters. Regarding the comparison of the diagnostic criteria, the criteria established by De Ferranti presented a higher positive proportion for the syndrome.

Conclusion: There were differences between the proportions obtained through the three diagnostic criteria, which may impair the diagnosis of the metabolic syndrome in adolescents.
Evaluating the Dynamical Stability of Outer Solar System Objects in the Presence of Planet Nine
Authors: Becker Juliette C. , Adams Fred C. , Khain Tali , Hamilton Stephanie J. , Gerdes David
Published: July 2017

We evaluate the dynamical stability of a selection of outer solar system objects in the presence of the proposed new solar system member Planet Nine. We use a Monte Carlo suite of numerical N-body integrations to construct a variety of orbital elements of the new planet and evaluate the dynamical stability of eight trans-Neptunian objects (TNOs) in the presence of Planet Nine. These simulations show that some combinations of orbital elements (

) result in Planet Nine acting as a stabilizing influence on the TNOs, which can otherwise be destabilized by interactions with Neptune. These simulations also suggest that some TNOs transition between several different mean-motion resonances during their lifetimes while still retaining approximate apsidal antialignment with Planet Nine. This behavior suggests that remaining in one particular orbit is not a requirement for orbital stability. As one product of our simulations, we present an a posteriori probability distribution for the semimajor axis and eccentricity of the proposed Planet Nine based on TNO stability. This result thus provides additional evidence that supports the existence of this proposed planet. We also predict that TNOs can be grouped into multiple populations of objects that interact with Planet Nine in different ways: one population may contain objects like Sedna and 2012 VP113, which do not migrate significantly in semimajor axis in the presence of Planet Nine and tend to stay in the same resonance; another population may contain objects like 2007 TG422 and 2013 RF98, which may both migrate and transition between different resonances.
Absence of a Metallicity Effect for Ultra-short-period Planets*
Authors: Winn Joshua N. , Sanchis-Ojeda Roberto , Rogers Leslie , Petigura Erik A. , Howard Andrew W. , Isaacson Howard , Marcy Geoffrey W. , Schlaufman Kevin C. , Cargile Phillip , Hebb Leslie
Published: July 2017

Ultra-short-period (USP) planets are a newly recognized class of planets with periods shorter than one day and radii smaller than about 2 R
⊕. It has been proposed that USP planets are the solid cores of hot Jupiters that have lost their gaseous envelopes due to photo-evaporation or Roche lobe overflow. We test this hypothesis by asking whether USP planets are associated with metal-rich stars, as has long been observed for hot Jupiters. We find the metallicity distributions of USP-planet and hot-Jupiter hosts to be significantly different (p = 3 × 10−4) based on Keck spectroscopy of Kepler stars. Evidently, the sample of USP planets is not dominated by the evaporated cores of hot Jupiters. The metallicity distribution of stars with USP planets is indistinguishable from that of stars with short-period planets with sizes between 2 and 4 R
⊕. Thus, it remains possible that the USP planets are the solid cores of formerly gaseous planets that are smaller than Neptune.
Feedback by AGN Jets and Wide-angle Winds on a Galactic Scale
Authors: Dugan Zachary , Gaibler Volker , Silk Joseph
Published: July 2017

To investigate the differences in mechanical feedback from radio-loud and radio-quiet active galactic nuclei on the host galaxy, we perform 3D AMR hydrodynamic simulations of wide-angle, radio-quiet winds with different inclinations on a single, massive, gas-rich disk galaxy at a redshift of 2–3. We compare our results to hydrodynamic simulations of the same galaxy but with a jet. The jet has an inclination of 0° (perpendicular to the galactic plane), and the winds have inclinations of 0°, 45°, and 90°. We analyze the impact on the host’s gas, star formation, and circumgalactic medium. We find that jet feedback is energy-driven and wind feedback is momentum-driven. In all the simulations, the jet or wind creates a cavity mostly devoid of dense gas in the nuclear region where star formation is then quenched, but we find strong positive feedback in all the simulations at radii greater than 3 kpc. All four simulations have similar SFRs and stellar velocities with large radial and vertical components. However, the wind at an inclination of 90° creates the highest density regions through ram pressure and generates the highest rates of star formation due to its ongoing strong interaction with the dense gas of the galactic plane. With increased wind inclination, we find greater asymmetry in gas distribution and resulting star formation. Our model generates an expanding ring of triggered star formation with typical velocities of the order of 1/3 of the circular velocity, superimposed on the older stellar population. This should result in a potentially detectable blue asymmetry in stellar absorption features at kiloparsec scales.
Search for Exoplanets around Northern Circumpolar Stars. II. The Detection of Radial Velocity Variations in M Giant Stars HD 36384, HD 52030, and HD 208742
Authors: Lee Byeong-Cheol , Jeong Gwanghui , Park Myeong-Gu , Han Inwoo , Mkrtichian David E. , Hatzes Artie P. , Gu Shenghong , Bai Jinming , Lee Sang-Min , Oh Hyeong-Il , Kim Kang-Min
Published: July 2017

We present the detection of long-period RV variations in HD 36384, HD 52030, and HD 208742 by using the high-resolution, fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) for the precise radial velocity (RV) survey of about 200 northern circumpolar stars. Analyses of RV data, chromospheric activity indicators, and bisector variations spanning about five years suggest that the RV variations are compatible with planet or brown dwarf companions in Keplerian motion. However, HD 36384 shows photometric variations with a period very close to that of RV variations as well as amplitude variations in the weighted wavelet Z-transform (WWZ) analysis, which argues that the RV variations in HD 36384 are from the stellar pulsations. Assuming that the companion hypothesis is correct, HD 52030 hosts a companion with minimum mass 13.3 M
Jup orbiting in 484 days at a distance of 1.2 au. HD 208742 hosts a companion of 14.0 M
Jup at 1.5 au with a period of 602 days. All stars are located at the asymptotic giant branch (AGB) stage on the H–R diagram after undergoing the helium flash and leaving the giant clump.With stellar radii of 53.0 R
⊙ and 57.2 R
⊙ for HD 52030 and HD 208742, respectively, these stars may be the largest yet, in terms of stellar radius, found to host substellar companions. However, given possible RV amplitude variations and the fact that these are highly evolved stars, the planet hypothesis is not yet certain.
Variability in GRMHD Simulations of Sgr
: Implications for EHT Closure Phase Observations
Authors: Medeiros Lia , Chan Chi-kwan , Özel Feryal , Psaltis Dimitrios , Kim Junhan , Marrone Daniel P. , Sa̧dowski Aleksander
Published: July 2017

Closure phases along different baseline triangles carry a large amount of information regarding the structures of the images of black holes in interferometric observations with the Event Horizon Telescope. We use long time span, high cadence, GRMHD+radiative transfer models of Sgr A* to investigate the expected variability of closure phases in such observations. We find that, in general, closure phases along small baseline triangles show little variability, except in the cases when one of the triangle vertices crosses one of the small regions of low visibility amplitude. The closure phase variability increases with the size of the baseline triangle, as larger baselines probe the small-scale structures of the images, which are highly variable. On average, the funnel-dominated MAD models show less closure phase variability than the disk-dominated SANE models, even in the large baseline triangles, because the images from the latter are more sensitive to the turbulence in the accretion flow. Our results suggest that image reconstruction techniques need to explicitly take into account the closure phase variability, especially if the quality and quantity of data allow for a detailed characterization of the nature of variability. This also implies that, if image reconstruction techniques that rely on the assumption of a static image are utilized, regions of the u–v space that show a high level of variability will need to be identified and excised.
Formation of Globular Clusters with Internal Abundance Spreads in r-Process Elements: Strong Evidence for Prolonged Star Formation
Authors: Bekki Kenji , Tsujimoto Takuji
Published: July 2017

Several globular clusters (GCs) in the Galaxy are observed to show internal abundance spreads in r-process elements (e.g., Eu). We propose a new scenario that explains the origin of these GCs (e.g., M5 and M15). In this scenario, stars with no/little abundance variations first form from a massive molecular cloud (MC). After all of the remaining gas of the MC is expelled by numerous supernovae, gas ejected from asymptotic giant branch stars can be accumulated in the central region of the GC to form a high-density intracluster medium (ICM). Merging of neutron stars then occurs to eject r-process elements, which can be efficiently trapped in and subsequently mixed with the ICM. New stars formed from the ICM can have r-process abundances that are quite different from those of earlier generations of stars within the GC. This scenario can explain both (i) why r-process elements can be trapped within GCs and (ii) why GCs with internal abundance spreads in r-process elements do not show [Fe/H] spreads. Our model shows (i) that a large fraction of Eu-rich stars can be seen in Na-enhanced stellar populations of GCs, as observed in M15, and (ii) why most of the Galactic GCs do not exhibit such internal abundance spreads. Our model demonstrates that the observed internal spreads of r-process elements in GCs provide strong evidence for prolonged star formation (∼108 yr).
A Space-based Observational Strategy for Characterizing the First Stars and Galaxies Using the Redshifted 21 cm Global Spectrum
Authors: Burns Jack O. , Bradley Richard , Tauscher Keith , Furlanetto Steven , Mirocha Jordan , Monsalve Raul , Rapetti David , Purcell William , Newell David , Draper David , MacDowall Robert , Bowman Judd , Nhan Bang , Wollack Edward J. , Fialkov Anastasia , Jones Dayton , Kasper Justin C. , Loeb Abraham , Datta Abhirup , Pritchard Jonathan , Switzer Eric , Bicay Michael
Published: July 2017

The redshifted 21 cm monopole is expected to be a powerful probe of the epoch of the first stars and galaxies (

). The global 21 cm signal is sensitive to the thermal and ionization state of hydrogen gas and thus provides a tracer of sources of energetic photons—primarily hot stars and accreting black holes—which ionize and heat the high redshift intergalactic medium (IGM). This paper presents a strategy for observations of the global spectrum with a realizable instrument placed in a low-altitude lunar orbit, performing night-time 40–120 MHz spectral observations, while on the farside to avoid terrestrial radio frequency interference, ionospheric corruption, and solar radio emissions. The frequency structure, uniformity over large scales, and unpolarized state of the redshifted 21 cm spectrum are distinct from the spectrally featureless, spatially varying, and polarized emission from the bright foregrounds. This allows a clean separation between the primordial signal and foregrounds. For signal extraction, we model the foreground, instrument, and 21 cm spectrum with eigenmodes calculated via Singular Value Decomposition analyses. Using a Markov Chain Monte Carlo algorithm to explore the parameter space defined by the coefficients associated with these modes, we illustrate how the spectrum can be measured and how astrophysical parameters (e.g., IGM properties, first star characteristics) can be constrained in the presence of foregrounds using the Dark Ages Radio Explorer (DARE).
Physics of Galactic Metals: Evolutionary Effects due to Production, Distribution, Feedback, and Interaction with Black Holes
Authors: Choi Ena , Ostriker Jeremiah P. , Naab Thorsten , Somerville Rachel S. , Hirschmann Michaela , Núñez Alejandro , Hu Chia-Yu , Oser Ludwig
Published: July 2017

We ask how the inclusion of various physical heating processes due to the metal content of gas affects the evolution of central massive galaxies and compute a suite of cosmological hydrodynamical simulations that follow these systems and their supermassive black holes. We use a smoothed particle hydrodynamics code with a pressure-entropy formulation and a more accurate treatment of the metal production, turbulent diffusion, and cooling rate based on individual element abundances. The feedback models include (1) active galactic nucleus (AGN) feedback via high-velocity broad absorption line winds and Compton/photoionization heating; (2) stellar feedback from multiple processes, including powerful winds from supernovae, stellar winds from young massive stars, and AGB stars, as well as radiative heating within Str

mgren spheres; and (3) additional heating effects due to the presence of metals, including grain photoelectric heating and metallicity-dependent X-ray heating by nearby accreting black holes and from the cosmic X-ray background. With a suite of zoom-in simulations of 30 halos with

, we show that energy and momentum budgeted from all feedback effects generate realistic galaxy properties. We explore the detailed role of each feedback model with three additional sets of simulations with varying input physics. We show that the metal-induced heating reduces the fraction of accreted stellar material but overall has a relatively minor effect on the massive central galaxies. The inclusion of AGN feedback significantly improves the ability of our simulations to yield realistic gas and stellar properties of massive galaxies with a reasonable accreted star fraction from other galaxies.
An Imperfectly Passive Nature: Bright Submillimeter Emission from Dust-obscured Star Formation in the z = 3.717 “Passive” System, ZF 20115
Authors: Simpson J. M. , Smail Ian , Wang Wei-Hao , Riechers D. , Dunlop J. S. , Ao Y. , Bourne N. , Bunker A. , Chapman S. C. , Chen Chian-Chou , Dannerbauer H. , Geach J. E. , Goto T. , Harrison C. M. , Hwang H. S. , Ivison R. J. , Kodama Tadayuki , Lee C.-H. , Lee H.-M. , Lee M. , Lim C.-F. , Michałowski M. J. , Rosario D. J. , Shim H. , Shu X. W. , Swinbank A. M. , Tee W.-L. , Toba Y. , Valiante E. , Wang Junxian , Zheng X. Z.
Published: July 2017

The identification of high-redshift, massive galaxies with old stellar populations may pose challenges to some models of galaxy formation. However, to securely classify a galaxy as quiescent, it is necessary to exclude significant ongoing star formation, something that can be challenging to achieve at high redshifts. In this Letter, we analyze deep ALMA/870 μm and SCUBA-2/450 μm imaging of the claimed “post-starburst” galaxy ZF 20115 at z = 3.717 that exhibits a strong Balmer break and absorption lines. The rest-frame far-infrared imaging identifies a luminous starburst 0.″4 ± 0.″1 (∼3 kpc in projection) from the position of the ultraviolet/optical emission and is consistent with lying at the redshift of ZF 20115. The star-forming component, with an obscured star formation rate of

, is undetected in the rest-frame ultraviolet but contributes significantly to the lower angular resolution photometry at rest-frame wavelengths ≳3500 Å. This contribution from the obscured starburst, especially in the Spitzer/IRAC wavebands, significantly complicates the determination of a reliable stellar mass for the ZF 20015 system, and we conclude that this source does not pose a challenge to current models of galaxy formation. The multi-wavelength observations of ZF 20115 unveil a complex system with an intricate and spatially varying star formation history. ZF 20115 demonstrates that understanding high-redshift obscured starbursts will only be possible with multi-wavelength studies that include high-resolution observations, available with the James Webb Space Telescope, at mid-infrared wavelengths.
Diagnosing the Kinematics of the Tori in Active Galactic Nuclei with the Velocity-resolved Reverberation Mapping of the Narrow Iron Kα Line
Authors: Liu 刘 Yuan 元 , Li 李小 Xiaobo 波
Published: July 2017

The properties of the dusty tori in active galactic nuclei (AGNs) have been investigated in detail, mainly focusing on the geometry and components; however, the kinematics of the torus are still not clear. The narrow iron Kα line at 6.4 keV is thought to be produced by the X-ray reflection from the torus. Thus, the velocity-resolved reverberation mapping of it is able to constrain the kinematics of the torus. Such effort is limited by the spectral resolution of current charged coupled device (CCD) detectors and should be possible with the microcalorimeter on the next generation X-ray satellite. In this paper, we first construct the response functions of the torus under a uniform inflow, a Keplerian rotation, and a uniform outflow. Then the energy-dependent light curve of the narrow iron Kα line is simulated according to the performance of the X-ray Integral Field Unit in Athena. Finally, the energy-dependent cross-correlation function is calculated to reveal the kinematic signal. According to our results, 100 observations with 5 ks exposure of each are sufficient to distinguish the above three velocity fields. Although the real geometry and velocity field of the torus could be more complex than we assumed, the present result proves the feasibility of the velocity-resolved reverberation mapping of the narrow iron Kα line. The combination of the dynamics of the torus with those of the broad-line region and the host galaxy is instructive for the understanding of the feeding and feedback process of AGNs.
Mesure des attitudes à l’égard de l’Unité locale pour l’inclusion scolaire
Authors: Desombre Caroline , Brasselet Célénie , Anegmar Souad , Durand-Delvigne Annick
Published: July 2017

Cette étude vise à analyser les attitudes d’élèves de cycles 2 et 3 envers les élèves de l’ULIS-école (Unité locale pour l’inclusion scolaire – école). Pour ce faire, nous avons interrogé 156 élèves âgés de six à neuf ans. Ils devaient livrer leurs attitudes – c’est-à-dire leurs croyances, les sentiments éprouvés et leurs intentions comportementales – envers l’inclusion dans leur classe d’un élève présenté, suivant les conditions, soit comme un élève de l’ULIS de leur école soit comme un élève tout-venant d’une autre école. Nos résultats montrent que, quelle que soit la condition, les attitudes sur les dimensions cognitive, conative et affective envers les élèves de l’ULIS ne sont pas négatives et que les croyances stéréotypées ne semblent pas encore présentes à ces âges. Les résultats sont discutés au regard du dispositif de l’ULIS et de son apport pour les élèves – qu’ils soient handicapés ou non.
Approche didactique de pratiques de débat philosophique en classes d’école primaire : relèvent-elles d’une discipline scolaire ?
Authors: Berton Bettina
Published: July 2017

La construction sociale des pratiques de débat philosophique, qui se développent en France depuis une quinzaine d’années à l’école primaire, est examinée, ici, dans une perspective didactique : ces pratiques s’enracinent-elles dans une discipline scolaire, existante ou renouvelée ou qui serait à constituer ? Relèvent-elles plutôt d’une construction non disciplinaire ? Un corpus de onze transcriptions de séances de classe, réparties sur les trois cycles, est étudié. Les résultats, obtenus à l’issue de l’examen des variations autour d’une dimension philosophique en jeu, des thèmes et des tâches identifiables en situation d’interactions langagières entre enseignants et élèves, permettent de conclure, à titre provisoire, à des constructions majoritairement non disciplinaires du genre et des contenus.
L’espoir et l’effroi. Les entreprises agricoles face au changement climatique (XVII e -XIX e siècle)
Authors: Locher Fabien , Fressoz Jean-Baptiste
Published: July 2017

Du XVII e au XIX e siècle, les sociétés européennes ont fait de la perspective d’un changement climatique, possiblement causé par l’action humaine, un grand motif d’espoir (améliorer le climat) ou de crainte (subir sa dégradation). Cette histoire longue des réflexions et des actions motivées par la notion d’un agir climatique humain recoupe en plusieurs sens celle des entreprises, de la production et du travail. C’est notamment vrai en matière agricole. L’idée d’amélioration climatique a servi, à l’époque moderne, à promouvoir un certain modèle (agraire) de colonisation de l’Amérique du Nord, et à y attirer de la main-d’œuvre. Au XIX e siècle, les interrogations sur l’impact d’une dégradation climatique sur les cultures viticoles ont suscité la mise au point d’un outil, le diagnostic par les dates de vendanges, aujourd’hui central en climatologie historique. La création de sociétés capitalistes de « mise en valeur » et d’aménagement de la France a enfin pu, dès les décennies 1820 et 1830, être menée au nom d’objectifs explicites de restauration du climat et de la nature françaises.