bluuebunny/crossref_metadata_2025 huggingface dataset:
Visual Localization across Seasons Using Sequence Matching Based on Multi-Feature Combination
Authors: Qiao Yongliang , Cappelle Cindy , Ruichek Yassine
Published: October 2017

Visual localization is widely used in autonomous navigation system and Advanced Driver Assistance Systems (ADAS). However, visual-based localization in seasonal changing situations is one of the most challenging topics in computer vision and the intelligent vehicle community. The difficulty of this task is related to the strong appearance changes that occur in scenes due to weather or season changes. In this paper, a place recognition based visual localization method is proposed, which realizes the localization by identifying previously visited places using the sequence matching method. It operates by matching query image sequences to an image database acquired previously (video acquired during traveling period). In this method, in order to improve matching accuracy, multi-feature is constructed by combining a global GIST descriptor and local binary feature CSLBP (Center-symmetric local binary patterns) to represent image sequence. Then, similarity measurement according to Chi-square distance is used for effective sequences matching. For experimental evaluation, the relationship between image sequence length and sequences matching performance is studied. To show its effectiveness, the proposed method is tested and evaluated in four seasons outdoor environments. The results have shown improved precision–recall performance against the state-of-the-art SeqSLAM algorithm.
Caregivers’ Use of Child Passenger Safety Resources and Quality of Future Child Restraint System Installations
Authors: Mirman Jessica H. , Seifert Sara J. , Metzger Kristi , Durbin Dennis R. , Arbogast Kristy B. , Zonfrillo Mark R.
Published: October 2017

Objectives: Child Restraint System (CRS) misuse is common. We characterized caregivers’ use of child passenger safety informational and instructional resources and determined whether there were differences in the quality of CRS installations associated with prior exposure to specific resources as evaluated in a standardized CRS installation environment. Methods: Caregivers completed self-report surveys and installed a forward-facing CRS in a controlled environment. Installations were evaluated for security (tightness) and accuracy (no errors) by a child passenger safety technician (CPST). Results: CRS manuals were the most common way caregivers learned to install a CRS. Primary care providers (PCP)s were the most frequently endorsed source of CRS safety information. There was no strong pattern of associations between prior exposure to resources and installation quality (security or accuracy), although some evidence supports protective effects of learning from CPSTs; 13% (19 out of 151) installations were secure and 57% (86 out of 151) installations were accurate. Conclusions: A focus on developing effective and lasting behavioral interventions is needed.
Hydrogen Sulfide Releasing 2-Mercaptoacrylic Acid-Based Derivative Possesses Cytoprotective Activity in a Small Intestine of Rats with Medication-Induced Enteropathy
Authors: Sklyarova Yulia , Fomenko Iryna , Lozynska Iryna , Lozynskyi Andrii , Lesyk Roman , Sklyarov Alexandr
Published: October 2017

Small intestinal injury is known to be one of the most commonly appearing pathologies, resulting in the use of medications such as: nonsteroidal anti-inflammatory drugs (NSAIDs), antitumor drugs and angiotensin-converting enzyme (ACE) inhibitors. The principal objective of this study is to evaluate the action of a novel mercaptoacrylic acid derivative able to release H2S on parameters of NO-synthase system and oxidative stress. Inducing enteropathy, three types of medications were used: indomethacin, an NSAID (35 mg/kg); methotrexate, an antitumor drug (10 mg/kg); and enalapril, an ACE inhibitor (2 mg/kg/day). 2-[(4-chlorophenyl-carbamoyl)-methyl]-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-acrylic acid (2C3DHTA) was introduced based on the background of medication-induced enteropathy (10 mg/kg/day). The survey showed that malondialdehyde (MDA) concentration, myeloperoxidase (MPO) activity, superoxide dismutase (SOD), catalase, and NO-synthases (NOS) were determined in the small intestinal mucosa. The increase in inducible NO-synthase (iNOS) activity was due to indomethacin and methotrexate administration. Constitutive NO-synthase (cNOS) activity was decreased by an ACE-inhibitor. The cytoprotective effect was demonstrated by 2C3DHTA, which returned iNOS activity to its control level and increased cNOS activity. The enterotoxic action of studied medication was accompanied by the development of oxidative stress manifested, activity of MPO was increased. MPO activity and manifestations of oxidative stress were decreased by 2C3DHTA. Effects of 2C3DHTA can be explained by the action of H2S, released from this compound in the gastrointestinal (GI) system.
Effect of a Hexagonal Barbell on the Mechanical Demand of Deadlift Performance
Authors: Lake Jason , Duncan Freddie , Jackson Matt , Naworynsky David
Published: October 2017

This study compared typical mechanical variables of interest obtained directly from barbell motion during deadlift performance with a conventional (CBD) and a hexagonal barbell (HBD). Eleven men, proficient with both deadlift variations, volunteered to participate in the study (age: 20.3 ± 0.6 years; height: 175.5 ± 8.5 m; mass: 88.7 ± 19.0 kg; CBD 1RM: 183 ± 22 kg; HBD 1RM: 194 ± 20 kg). During the first session, CBD and HBD 1RM was assessed; during the second session, they performed 3 sets of 1 CBD repetition with 90% 1RM; and in session three, they repeated this process with the HBD. Barbell displacement was recorded at 1000 Hz and mechanical parameters derived from this. Significantly heavier loads were lifted during HBD (6%, p = 0.003). There were no significant differences between barbell displacement (p = 0.216). However, HBD was performed significantly faster (15%, p = 0.012), HBD load was accelerated for significantly longer (36%, p = 0.004), and significantly larger mean forces underpinned this (6%, p < 0.001), with more work having been performed (7%, p < 0.001) at greater power outputs (28%, p < 0.001). The results of this study showed that heavier HBD loads can be lifted through the same range of motion faster, and that this load is accelerated for significantly longer. The strategies used to achieve these differences could have a significant effect on training outcomes.
A Synthesis of Studies on Land Use and Land Cover Dynamics during 1930–2015 in Bangladesh
Authors: Rai Raju , Zhang Yili , Paudel Basanta , Li Shicheng , Khanal Narendra
Published: October 2017

Land use and land cover (LULC) is dynamic and changes in it have important environmental and socio-economic consequences. The pathways and pace of change vary with space and time and are related to the interaction between human activities and biophysical conditions in an area. This study provides a systematic review of the changing status, patterns, and compositions of LULC in Bangladesh on national, regional, and local scales over the past 85 years. The primary LULC classes in Bangladesh are agricultural land, urban and built-up area, forest and vegetation, water bodies, and wetlands. Most of the country is covered with agricultural land, followed by urban areas; the latter has been expanding rapidly in the area surrounding the capital city, Dhaka, especially the southern capital area. Forest cover is mostly concentrated in southeast Bangladesh, the Chittagong district, and the mangrove forests are predominantly located in the southwest, with the Gangetic delta. High population growth, rapid urbanization, and infrastructure development have been directly associated with changing patterns of land use across the country. In recent decades, urban areas and water bodies have been increasing, to the detriment of both forests and agricultural land. Most of the studies reviewed here describe a general trend involving agricultural and forested land being transformed into urban areas.
Using DEMATEL and Intuitionistic Fuzzy Sets to Identify Critical Factors Influencing the Recycling Rate of End-Of-Life Vehicles in China
Authors: Gan Junwei , Luo Li
Published: October 2017

At present, the recycling rate of End-of-life vehicles (ELVs) in China is far lower than the heavily motorized countries, resulting in severe environmental pollution, waste of resource and hidden traffic troubles, which has a negative impact on China’s economic and social sustainable development. With the arrival of the peak season of generating ELVs in China, it is urgent and important to improve the recycling rate of ELVs. The recycling rate of ELVs is influenced by multiple factors together. The existing research about the identification of influence factors of ELV recycling rate fewer considers the interaction effect among different factors. To fill the gap, firstly the influence factors are analyzed from standpoints of economy, policy, recycling network and others. Then a hybrid model based on DEMATEL (decision making trial and evaluation laboratory) and intuitionistic fuzzy sets is employed to examine the cause–effect relationships among factors. In the study, the vagueness of decision makers’ judgment and linguistic inaccuracy is dealt with effectively by intuitionistic fuzzy sets. The research results reveal “fiscal subsidy”, “government’s restrictive policies to reuse ELVs parts”, “coordination of the industry agencies”, “participation of automobile manufacturer” and “supervision of the government” are most significant criteria influencing the recycling rate of ELVs in China. A sensitivity analysis is conducted to verify the robustness of results. Lastly, according to the critical influencing factors identified, some pertinent suggestions to the government, ELV recycling enterprise, owner and vehicle manufacturer are put forward. In addition, the future research directions are proposed.
Carbohydrates Components of Some Italian Local Landraces: Garlic (Allium sativum L.)
Authors: Lisciani Silvia , Gambelli Loretta , Durazzo Alessandra , Marconi Stefania , Camilli Emanuela , Rossetti Cecilia , Gabrielli Paolo , Aguzzi Altero , Temperini Olindo , Marletta Luisa
Published: October 2017

Garlic is one of the most widespread and ancient medicinal plants. Its health benefits are due to its chemical components, and among these is carbohydrate, whose characteristics have been so far little investigated. The aim of this study is to typify the various components of carbohydrate (starch, individual sugars, fructans, and total dietary fibre) in four commonly consumed “Italian local landraces”: Bianco Piacentino, Rosso di Castelliri, Rosso di Sulmona, Rosso di Proceno, which are grown in two different geographical areas—Viterbo and Alvito—under the same agronomic conditions. This study will also evaluate how genotype and the cultivation area can affect the profile of the carbohydrate components of these landrace strains. Regarding unavailable carbohydrates, all of the varieties showed appreciable contents of fructans, the most representative component, which ranged from 45.8 to 54.4 g/100 g d.w. In contrast, total dietary fibre values varied from 9.1 to 13.1 g/100 g d.w. in Rosso di Castelliri and Bianco Piacentino, respectively, which are both grown in Viterbo. As for starch, only some traces were found, while the amount of total sugars ranged between 2.12 and 3.27 g/100 g d.w., with higher levels of sucrose. Our findings could provide important information that may be adopted to enhance and promote the quality of some local Italian garlic landraces through highlighting the influence that the cultivar and the environmental conditions can have on carbohydrates components.
A Co-Word Analysis of Organizational Constraints for Maintaining Sustainability
Authors: Guo Daoyan , Chen Hong , Long Ruyin , Lu Hui , Long Qianyi
Published: October 2017

A good understanding of organizational constraints is vital to facilitate organizational development as the sustainable development of organizations can be constrained by the organization itself. In this study, bibliometric methods were adopted to investigate the research status and trends of organizational constraints. The findings showed that there were 1138 articles and reviews, and 52 high-frequency keywords related to organizational constraints during the period 1980–2016. The research cores were “constraints”, “learning”, “institution”, and “behavior” in the co-occurrence network, and “constraints” played the most significant role. The 52 high-frequency keywords were classified into six clusters: “change and decision-making”, “supply chain and sustainability”, “human system and performance”, “culture and relations”, “entrepreneur and resource”, and “learning and innovation”. Furthermore, the indicators of organizational development (e.g., innovation, supply chain, decision-making, performance, sustainability, and employee behavior) were found to be significantly related to the organizational constraints. Based on these findings, future trends were proposed to maintain the sustainability of organizations. This study investigated the state of the art in terms of organizational constraints and provided valuable references for maintaining the sustainable development of organizations.
Effect of Clostridium perfringens β-Toxin on Platelets
Authors: Thiel Anne , Mogel Helga , Bruggisser Julia , Baumann Arnaud , Wyder Marianne , Stoffel Michael , Summerfield Artur , Posthaus Horst
Published: October 2017

Clostridium perfringens β-toxin (CPB) is the major virulence factor of C. perfringens type C causing a hemorrhagic enteritis in animals and humans. In experimentally infected pigs, endothelial binding of CPB was shown to be associated with early vascular lesions and hemorrhage but without obvious thrombosis of affected vessels, suggesting altered hemostasis in the early phase of the disease. The objective of the present study was to investigate the effect of CPB on platelets, with respect to primary hemostasis. Our results demonstrate that CPB binds to porcine and human platelets and forms oligomers resulting in a time- and dose-dependent cell death. Platelets showed rapid ultrastructural changes, significantly decreased aggregation and could no longer be activated by thrombin. This indicates that CPB affects the physiological function of platelets and counteracts primary hemostasis. Our results add platelets to the list of target cells of CPB and extend the current hypothesis of its role in the pathogenesis of C. perfringens type C enteritis.
Identifying people with a learning disability: an advanced search for general practice
Authors: Russell Amy M , Bryant Louise , House Allan
Published: October 2017

Background

People with learning disabilities (LD) have poor physical and mental health when compared with the general population. They are also likely to find it more difficult than others to describe their symptoms adequately. It is therefore harder for healthcare workers to identify the health needs of those with learning disabilities, with the danger of some problems being left unrecognised. Practice registers record only a proportion of those who are eligible, making it difficult to target improvements in their health care.

Aim

To test a Read Code search supporting the identification of people with a mild-to-moderate learning disability who are not currently on the learning disability register.

Design and setting

An observational study in primary care in West Yorkshire.

Method

Read Code searches were created to identify individuals with a learning disability not on the LD register; they were field tested and further refined before testing in general practice.

Results

Diagnostic codes identified small numbers of individuals who should have been on the LD register. Functional and service use codes often created large numbers of false-positive results. The specific descriptive codes ‘Learning difficulties’ and ‘Referral to learning disability team’ needed follow-up review, and then identified some individuals with LD who were not on the register.

Conclusion

The Read Code search supported practices to populate their registers and was quick to run and review, making it a viable choice to support register revalidation. However, it did not find large numbers of people eligible for the LD register who were previously unidentified by their practice, suggesting that additional complementary methods are required to support practices to validate their registers.
GPs’ experiences of children with anxiety disorders in primary care: a qualitative study
Authors: O’Brien Doireann , Harvey Kate , Young Bridget , Reardon Tessa , Creswell Cathy
Published: October 2017

Background

Anxiety disorders have a median age of onset of 11 years and are the most common emotional disorders in childhood; however, a significant proportion of those affected do not access professional support. In the UK, GPs are often the first medical professional that families see so are in a prime position to support children with anxiety disorders; however, currently there is little research available on GPs’ perspectives on and experiences of supporting children with these disorders.

Aim

To explore the experiences of GPs in relation to identification, management, and access to specialist services for children (<12 years) with anxiety disorders.

Design and setting

Twenty semi-structured interviews were conducted with GPs in primary care throughout England.

Method

GPs reflected a diverse group in relation to the ethnic and socioeconomic profile of registered patients, GP age, sex, professional status, previous engagement with research, and practice size and location. Purposive sampling was used to recruit GPs until theoretical saturation was reached. Data were analysed using a constant comparative method of thematic analysis.

Results

Data from 20 semi-structured interviews were organised into three themes: decision making, responsibility, and emotional response, with an overarching theme of GPs feeling ill equipped. These themes were retrospectively analysed to illustrate their role at different stages in the primary care process (identification, management, and access to specialist services).

Conclusion

GPs feel ill equipped to manage and support childhood anxiety disorders, demonstrating a need for medical training to include greater emphasis on children’s mental health, as well as potential for greater collaboration between primary and specialist services.
Patient-driven N-of-1 in Parkinson’s Disease
Authors: Riggare Sara , Unruh Kenton , Sturr Jasmine , Domingos Josefa , Stamford Jonathan , Svenningsson Per , Hägglund Maria
Published: October 2017

Background: New insights and knowledge in biomedical science often come from observation and experimentation. Methods traditionally used include self-experimentation, case reports, randomised controlled trials, and N-of-1 studies. Technological advances have lead to an increasing number of individuals and patients engaging in self-tracking. We use the term patient-driven N-of-1 for self-tracking performed with the explicit intention to disseminate the results by academic publishing.

Objectives: The aim of the study was to: 1) explore the potential role for patient-driven N-of-1 studies as a tool for improving self-management in Parkinson’s disease (PD) using the example of managing levodopa-induced dyskinesia (LID) with nicotine, and 2) based on this example; identify some specific challenges of patient-driven N-of-1 studies.

Methods: We used a placebo controlled patient-driven N-of-1 study with nicotine administered via e-cigarette to treat LID. The first author initiated and conducted the experiment on herself and noted her observations. The evaluations of the potential of N-of-1 for improving self-management of PD as well as the effects of nicotine on dyskinesia were based on the perception of the subject. During the planning and undertaking of the experiment, notes were made to identify challenges specific to patient-driven N-of-1 studies.

Results: The subject was able to distinguish a decrease of her LID from nicotine but no effect from placebo. The main challenges of patient-driven N-of-1 studies were identified to be associated with planning of the study, recruiting a suitable research team, making sure the data collection is optimal, analysis of data, and publication of results.

Conclusions: Our study indicates that nicotine administered via e-cigarette may have an effect on levodopa-induced dyskinesia in individual patients with PD. The main contribution is however highlighting the work done by patients on a daily basis for understanding their conditions and conducting self-tracking experiments. More work is needed to further develop methods around patient-driven N-of-1 studies for PD.
Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies
Authors: Mlostoń Grzegorz , Heimgartner Heinz
Published: October 2017

The scope of applications of dialkyl dicyanofumarates and maleates as highly functionalized electron-deficient dipolarophiles, dienophiles and Michael acceptors is summarized. The importance for the studies on reaction mechanisms of cycloadditions is demonstrated. Multistep reactions with 1,2-diamines and β-aminoalcohols leading to diverse five- and six-membered heterocycles are discussed. Applications of dialkyl dicyanofumarates as oxidizing agents in the syntheses of disulfides and diselenides are described. The reactions with metallocenes leading to charge-transfer complexes with magnetic properties are also presented.
Awareness, prevalence of hair smoothing products that contain formaldehyde and determinants of their harmful effects among women in Saudi Arabia
Authors: Hameed Yara Nasser , Elgharabway Rehab M , Ahmed Amira Saber
Published: October 2017

Individuals who use hair smoothing products at home or in a salon work environment are at risk of exposure to various chemical compounds. Formaldehyde mixed with keratin as a hair straightening product is in common use by women in Saudi Arabia. The high temperatures used during blow-drying can release gas fumes that have several implications to include irritation of the skin, eyes and respiratory complications. Furthermore, formaldehyde is classified as a known human carcinogen. The aim of this study is to assess the source of keratin hair treatment among women, demonstrate the symptoms related to formaldehyde exposure during keratin hair treatment process and determine the practices that can increase the exposure to formaldehyde and to evaluate the level of formaldehyde in the keratin hair treatment products. A national cross-sectional survey was first conducted during March-April 2017 on Saudi Arabian children and women aged between the age of 12 and 50 years old. A standardized, fully confidential questionnaire was provided to participating members. A total of 330 filled questionnaires were obtained within the study location. Moreover, 30 hair salons that used keratin-based products were visited in 3 different cities in Al Qassim province to check the location of keratin hair treatment, ventilation procedures and take samples of hair products that were later analyzed. Most commonly reported symptom was irritation of the eyes reported by 135 people. Other symptoms described include irritation of throat, burning sensation of the nose, headache and nausea. Argan e Ojon was one of the most famous product tested in this study with formaldehyde levels above 0.2% threshold (0.35%). It is worrying thatArgan e Ojon does not comply with GSO 1943 and SASO 1953 standards. A majority of salons demonstrated poor ventilation measures and failed to isolate their clients from the general public and salon workers. With the evident complications, more should be done to make people aware of the formaldehyde risks and prevent salons from using these products.
Insights from Synthetic Star-forming Regions. III. Calibration of Measurement and Techniques of Star Formation Rates
Authors: Koepferl Christine M. , Robitaille Thomas P. , Dale James E.
Published: October 2017

Through an extensive set of realistic synthetic observations (produced in Paper I), we assess in this part of the paper series (Paper III) how the choice of observational techniques affects the measurement of star formation rates (SFRs) in star-forming regions. We test the accuracy of commonly used techniques and construct new methods to extract the SFR, so that these findings can be applied to measure the SFR in real regions throughout the Milky Way. We investigate diffuse infrared SFR tracers such as those using 24 μm, 70 μm and total infrared emission, which have been previously calibrated for global galaxy scales. We set up a toy model of a galaxy and show that the infrared emission is consistent with the intrinsic SFR using extra-galactic calibrated laws (although the consistency does not prove their reliability). For local scales, we show that these techniques produce completely unreliable results for single star-forming regions, which are governed by different characteristic timescales. We show how calibration of these techniques can be improved for single star-forming regions by adjusting the characteristic timescale and the scaling factor and give suggestions of new calibrations of the diffuse star formation tracers. We show that star-forming regions that are dominated by high-mass stellar feedback experience a rapid drop in infrared emission once high-mass stellar feedback is turned on, which implies different characteristic timescales. Moreover, we explore the measured SFRs calculated directly from the observed young stellar population. We find that the measured point sources follow the evolutionary pace of star formation more directly than diffuse star formation tracers.
New Low-mass Eclipsing Binary Systems in Praesepe Discovered by K2
Authors: Gillen Edward , Hillenbrand Lynne A. , David Trevor J. , Aigrain Suzanne , Rebull Luisa , Stauffer John , Cody Ann Marie , Queloz Didier
Published: October 2017

We present the discovery and characterization of four low-mass (

M
<
0.6

M

⊙

) eclipsing binary (EB) systems in the sub-Gyr old Praesepe open cluster using Kepler/K2 time series photometry and Keck/HIRES spectroscopy. We present a new Gaussian process EB model, GP–EBOP, as well as a method of simultaneously determining effective temperatures and distances for EBs. Three of the reported systems (AD 3814, AD 2615 and AD 1508) are detached and double-lined, and precise solutions are presented for the first two. We determine masses and radii to 1%–3% precision for AD 3814 and to 5%–6% for AD 2615. Together with effective temperatures determined to ∼50 K precision, we test the PARSEC v1.2 and BHAC15 stellar evolution models. Our EB parameters are more consistent with the PARSEC models, primarily because the BHAC15 temperature scale is hotter than our data over the mid-M-dwarf mass range probed. Both ADs 3814 and 2615, which have orbital periods of 6.0 and 11.6 days, are circularized but not synchronized. This suggests that either synchronization proceeds more slowly in fully convective stars than the theory of equilibrium tides predicts, or magnetic braking is currently playing a more important role than tidal forces in the spin evolution of these binaries. The fourth system (AD 3116) comprises a brown dwarf transiting a mid-M-dwarf, which is the first such system discovered in a sub-Gyr open cluster. Finally, these new discoveries increase the number of characterized EBs in sub-Gyr open clusters by 20% (40%) below

M
<
1.5

M
⊙ (

M
<
0.6

M
⊙).
The Canada–France Imaging Survey: First Results from the u-Band Component
Authors: Ibata Rodrigo A. , McConnachie Alan , Cuillandre Jean-Charles , Fantin Nicholas , Haywood Misha , Martin Nicolas F. , Bergeron Pierre , Beckmann Volker , Bernard Edouard , Bonifacio Piercarlo , Caffau Elisabetta , Carlberg Raymond , Côté Patrick , Cabanac Rémi , Chapman Scott , Duc Pierre-Alain , Durret Florence , Famaey Benoît , Fabbro Sébastien , Gwyn Stephen , Hammer Francois , Hill Vanessa , Hudson Michael J. , Lançon Ariane , Lewis Geraint , Malhan Khyati , Matteo Paola di , McCracken Henry , Mei Simona , Mellier Yannick , Navarro Julio , Pires Sandrine , Pritchet Chris , Reylé Celine , Richer Harvey , Robin Annie C. , Jannsen Rubén Sánchez , Sawicki Marcin , Scott Douglas , Scottez Vivien , Spekkens Kristine , Starkenburg Else , Thomas Guillaume , Venn Kim
Published: October 2017

The Canada–France Imaging Survey (CFIS) will map the northern high Galactic latitude sky in the u-band (“CFIS-u,” 10,000

) and in the r-band (“CFIS-r,” 5000

), enabling a host of stand-alone science investigations, and providing some of the ground-based data necessary for photometric redshift determination for the Euclid mission. In this first contribution, we present the u-band component of the survey, describe the observational strategy, and discuss some first highlight results, based on approximately one-third of the final area. We show that the Galactic anticenter structure is distributed continuously along the line of sight, out to beyond

, and possesses a metallicity distribution that is essentially identical to that of the outer disk sampled by APOGEE. This suggests that it is probably a buckled disk of old metal-rich stars, rather than a stream or a flare. We also discuss the future potential for CFIS-u in discovering star-forming dwarf galaxies around the Local Group, the characterization of the white dwarf and blue straggler population of the Milky Way, as well as its sensitivity to low surface brightness structures in external galaxies.
The FluxCompensator: Making Radiative Transfer Models of Hydrodynamical Simulations Directly Comparable to Real Observations
Authors: Koepferl Christine M. , Robitaille Thomas P.
Published: October 2017

When modeling astronomical objects throughout the universe, it is important to correctly treat the limitations of the data, for instance finite resolution and sensitivity. In order to simulate these effects, and to make radiative transfer models directly comparable to real observations, we have developed an open-source Python package called the FluxCompensator that enables the post-processing of the output of 3D Monte Carlo radiative transfer codes, such as Hyperion. With the FluxCompensator, realistic synthetic observations can be generated by modeling the effects of convolution with arbitrary point-spread functions, transmission curves, finite pixel resolution, noise, and reddening. Pipelines can be applied to compute synthetic observations that simulate observatories, such as the Spitzer Space Telescope or the Herschel Space Observatory. Additionally, this tool can read in existing observations (e.g., FITS format) and use the same settings for the synthetic observations. In this paper, we describe the package as well as present examples of such synthetic observations.
Optical and UV Spectra of the Remnant of SN 1885 (S And) in M31*
Authors: Fesen Robert A. , Weil Kathryn E. , Hamilton Andrew J. S. , Höflich Peter A.
Published: October 2017

We present multi-slit, 1D and 2D optical and UV spectra of the remnant of supernova 1885 (SN 1885; S And) taken using the Hubble Space Telescope’s Imaging Spectrograph (HST/STIS). These spectra of this probable subluminous Type Ia remnant, seen in silhouette against the central bulge of the Andromeda galaxy (M31), show strong and broad absorptions from neutral and singly ionized species of calcium, magnesium, and iron but with strikingly different distributions. Calcium H and K absorption indicates spherically distributed Ca-rich ejecta, densest in a lumpy shell expanding at 2000–6000 km s−1. Equally broad but weaker Ca i 4227 Å absorption is seen to extend out to velocities of ∼13,000 km s−1. Magnesium-rich ejecta in the remnant are detected for the first time through Mg i 2852 Å and Mg ii 2796, 2803 Å absorptions concentrated in a shell with expansion velocities from

to at least 10,000 km s−1. Fe i 3720 Å absorption is detected as two discrete blueshifted and redshifted absorptions suggestive of an Fe i shell with expansion velocities of ±2000–8000 km s−1. Weak Fe ii resonance absorptions in the wavelength region 2300–2700 Å are consistent with prior HST UV images showing Fe ii–rich ejecta confined to a small number of optically thick plumes. The presence of such iron plumes extending out from the remnant’s core plus layered shells of calcium and magnesium point to a delayed-detonation explosion. The spectra also suggest a roughly spherical explosion, contrary to that expected by a merger or collision of two white dwarfs. We conclude that SN 1885 likely was an off-center, delayed-detonation explosion leading to a subluminous SN Ia similar to SN 1986G.
A Compressed Sensing-based Image Reconstruction Algorithm for Solar Flare X-Ray Observations
Authors: Felix Simon , Bolzern Roman , Battaglia Marina
Published: October 2017

One way of imaging X-ray emission from solar flares is to measure Fourier components of the spatial X-ray source distribution. We present a new compressed sensing-based algorithm named VIS_CS, which reconstructs the spatial distribution from such Fourier components. We demonstrate the application of the algorithm on synthetic and observed solar flare X-ray data from the Reuven Ramaty High Energy Solar Spectroscopic Imager satellite and compare its performance with existing algorithms. VIS_CS produces competitive results with accurate photometry and morphology, without requiring any algorithm- and X-ray-source-specific parameter tuning. Its robustness and performance make this algorithm ideally suited for the generation of quicklook images or large image cubes without user intervention, such as for imaging spectroscopy analysis.
The Small-scale Structure of Photospheric Convection Retrieved by a Deconvolution Technique Applied to Hinode/SP Data
Authors: Oba T. , Riethmüller T. L. , Solanki S. K. , Iida Y. , Quintero Noda C. , Shimizu T.
Published: October 2017

Solar granules are bright patterns surrounded by dark channels, called intergranular lanes, in the solar photosphere and are a manifestation of overshooting convection. Observational studies generally find stronger upflows in granules and weaker downflows in intergranular lanes. This trend is, however, inconsistent with the results of numerical simulations in which downflows are stronger than upflows through the joint action of gravitational acceleration/deceleration and pressure gradients. One cause of this discrepancy is the image degradation caused by optical distortion and light diffraction and scattering that takes place in an imaging instrument. We apply a deconvolution technique to Hinode/SP data in an attempt to recover the original solar scene. Our results show a significant enhancement in both the convective upflows and downflows but particularly for the latter. After deconvolution, the up- and downflows reach maximum amplitudes of −3.0 km s−1 and +3.0 km s−1 at an average geometrical height of roughly 50 km, respectively. We found that the velocity distributions after deconvolution match those derived from numerical simulations. After deconvolution, the net LOS velocity averaged over the whole field of view lies close to zero as expected in a rough sense from mass balance.
Insights from Synthetic Star-forming Regions. I. Reliable Mock Observations from SPH Simulations
Authors: Koepferl Christine M. , Robitaille Thomas P. , Dale James E. , Biscani Francesco
Published: October 2017

Through synthetic observations of a hydrodynamical simulation of an evolving star-forming region, we assess how the choice of observational techniques affects the measurements of properties that trace star formation. Testing and calibrating observational measurements requires synthetic observations that are as realistic as possible. In this part of the series (Paper I), we explore different techniques for mapping the distributions of densities and temperatures from the particle-based simulations onto a Voronoi mesh suitable for radiative transfer and consequently explore their accuracy. We further test different ways to set up the radiative transfer in order to produce realistic synthetic observations. We give a detailed description of all methods and ultimately recommend techniques. We have found that the flux around 20 μm is strongly overestimated when blindly coupling the dust radiative transfer temperature with the hydrodynamical gas temperature. We find that when instead assuming a constant background dust temperature in addition to the radiative transfer heating, the recovered flux is consistent with actual observations. We present around 5800 realistic synthetic observations for Spitzer and Herschel bands, at different evolutionary time-steps, distances, and orientations. In the upcoming papers of this series (Papers II, III, and IV), we will test and calibrate measurements of the star formation rate, gas mass, and the star formation efficiency using our realistic synthetic observations.
Tidal Dissipation in WASP-12
Authors: Weinberg Nevin N. , Sun Meng , Arras Phil , Essick Reed
Published: October 2017

WASP-12 is a hot Jupiter system with an orbital period of P = 1.1 days, making it one of the shortest-period giant planets known. Recent transit timing observations by Maciejewski et al. and Patra et al. found a decreasing period with

 = 3.2 Myr. This has been interpreted as evidence of either orbital decay due to tidal dissipation or a long-term oscillation of the apparent period due to apsidal precession. Here, we consider the possibility that it is orbital decay. We show that the parameters of the host star are consistent with either a M
* ≃ 1.3 M
⊙ main sequence star or a M
* ≃ 1.2 M
⊙ subgiant. We find that if the star is on the main sequence, the tidal dissipation is too inefficient to explain the observed

. However, if it is a subgiant, the tidal dissipation is significantly enhanced due to nonlinear wave-breaking of the dynamical tide near the star’s center. The subgiant models have a tidal quality factor

and an orbital decay rate that agrees well with the observed

. It would also explain why the planet survived for ≃3 Gyr while the star was on the main sequence and yet is now inspiraling on a 3 Myr timescale. Although this suggests that we are witnessing the last ∼0.1% of the planet’s life, the probability of such a detection is a few percent given the observed sample of ≃30 hot Jupiters in P < 3-day orbits around M
* > 1.2 M
⊙ hosts.
Meticulous Plasma Isolation is Essential to Avoid False Low-Level Viraemia in Roche Cobas HIV-1 Viral Load Assays
Authors: Mortier Virginie , Vancoillie Leen , Dauwe Kenny , Staelens Delfien , Demecheleer Els , Schauvliege Marlies , Dinakis Sylvie , Van Maerken Tom , Dessilly Géraldine , Ruelle Jean , Verhofstede Chris
Published: October 2017

Background

Pre-analytical sample processing is often overlooked as a potential cause of inaccurate assay results. Here we demonstrate how plasma, extracted from standard EDTA-containing blood collection tubes, may contain traces of blood cells consequently resulting in a false low-level HIV-1 viral load when using Roche Cobas HIV-1 assays.

Methods

The presence of human DNA in Roche Cobas 4800 RNA extracts and in RNA extracts from the Abbott HIV-1 RealTime assay was assessed by quantifying the human albumin gene by means of quantitative PCR. RNA was extracted from plasma samples before and after an additional centrifugation and tested for viral load and DNA contamination. The relation between total DNA content and viral load was defined.

Results

Elevated concentrations of genomic DNA were detected in 28 out of 100 Cobas 4800 extracts and were significantly more frequent in samples processed outside of the AIDS Reference Laboratory. An association between genomic DNA presence and spurious low-level viraemia results was demonstrated. Supplementary centrifugation of plasma before RNA extraction eliminated the contamination and the false viraemia.

Conclusions

Plasma isolated from standard EDTA-containing blood collection tubes may contain traces of HIV DNA leading to false viral load results above the clinical cutoff. Supplementary centrifugation of plasma before viral load analysis may eliminate the occurrence of this spurious low-level viraemia.
Species conservation profile of the rare and endemic trapdoor spider Calathotarsus simoni (Araneae, Migidae) from Central Argentina
Authors: Ferretti Nelson , Pompozzi Gabriel , Cardoso Pedro
Published: October 2017

Calathotarsus simoni Schiapelli & Gerschman 1975 is the only species of Migidae in Argentina. It is a rare and endemic spider only found in relict grassland of mountain systems in the province of Buenos Aires. This species is a habitat specialist spider occupying specific areas with certain microclimatic conditions on hilly and rocky grassland areas at about 500-1500 meters above sea level.

The observed extent of occurrence (EOO) is 7207 km2 and the area of occupancy (AOO) is 16 km2. Two locations are identified based on the threat event related to the invasion of the species habitat by alien woody plants. In addition, intensive cattle production and agriculture also constitute relevant threats to the species.
Quand les résistants deviennent des parties prenantes : une approche du changement organisationnel comme processus d’apprentissage
Authors: Boyer Pierre-Yves
Published: October 2017

Dans le cadre d’un changement organisationnel radical, la période de crise peut mener à l’émergence de résistances. La littérature décrit ces résistances comme majoritairement problématiques sans pour autant réussir à identifier clairement des solutions pour y remédier. Cependant, d’autres courants de recherche, dans lesquels se positionne cette étude, considèrent que certains comportements de résistance peuvent transformer significativement l’organisation avec le temps en l’amenant à faire émerger des solutions alternatives. Ainsi, en appui sur une étude qualitative inductive nous proposons un nouveau modèle d’apprentissage organisationnel, dont les résistances au changement deviennent l’une des étapes. Nos résultats aboutissent à la définition de quatre types de salariés résistants : Emergents, Nouveaux rebelles, Suiveurs et Oubliés. L’approche cognitive de la gouvernance du changement organisationnel nous conduit à proposer d’intégrer les résistants au changement comme de véritables parties prenantes.
Installation of Manifolds - A Success Story
Authors: Costa Lilson Terra , de Lima Ubirajara Alvarenga
Published: October 2017

The oil industry has faced growing demand for subsea facilities to enable the development of ultra deepwater oil fields. The use of manifold is an alternative widely considered in subsea arrangements. In order to apply this alternative, it is necessary to follow a chain of project that demands special care since its manufacture, installation, commissioning, productive life and possible demobilization, being able to culminate with the removal of equipment from the location. These equipments, sometimes weighing a few hundred tons, require special attention during planning the installation. Thus, this paper proposes to present the challenges faced in the planning and installation of subsea equipments in deepwater, the evolution of the manifold installation techniques at Petrobras, as well as present the main installation methods currently used in Pre-Salt fields and new techniques in development for the installation of large subsea equipments.
Professional nurses’ lived experiences regarding the performance management system in the Mopani district
Authors: Mboweni Sheillah H. , Makhado Lufuno
Published: October 2017

Background: The purpose of the performance management system (PMS) is planning, monitoring, evaluation and development of employees to meet the organisational goals and objectives and transform of service delivery to excellence of the organisation. However, public services are deteriorating and implementation of PMS stimulated different views among professional nurses (PNs) in the Mopani district clinics, which warrants exploration and documentation of the findings.Objective: The objective of this study was to explore and describe the PNs’ perceptions towards PMS.Methods: A qualitative, phenomenological research was conducted to explore and describe the nurses’ lived experiences regarding PMS. A purposive sampling method was used. Data collection was done using focus group interviews. Three focus group discussion sessions were conducted, inclusive of six to nine participants in each session.Results: Twenty-two PNs were interviewed. The findings revealed the following themes: PNs’ uncertainty regarding the implementation of PMS, poor implementation of PMS and its process, lack of knowledge and understanding of PMS implementation and its process, and negative attitudes towards the implementation of PMS.Conclusion: PNs perceived PMS negatively. There is a need to improve leadership and management behaviour by enhancing productivity, job satisfaction and organisational commitment. Constructive feedback, training and capacity development, including standardisation and stabilisation of performance instrument, might improve the process.
Men’s reproductive health knowledge in Mankweng District, Limpopo Province
Authors: Rasesemola Richard M. , Ramukumba Tendani S. , Masala-Chokwe Majapi , Nkosi Zerish Z.
Published: October 2017

Background: Gender roles influence men’s attitudes towards reproductive health, and society might assume that reproductive health issues, fertility and family planning are women’s responsibilities. Moreover, literature shows that men have insufficient knowledge about reproductive health matters and some misconceptions about modern contraceptive practices.Objectives: The aim of the study was to describe reproductive health knowledge of men in Mankweng District and was conducted in 2015.Methods: A descriptive research study was conducted by using quantitative approach. Data were collected by means of questionnaires. Cluster random multistage sampling was used to select villages in Mankweng District and convenient sampling was used to identify participants who met the inclusion criteria to participate on the study.Results: A total of 200 questionnaires were distributed and returned; 197 (98.5%) of the returned questionnaires were eligible for analysis. The findings indicated that the majority of participants, 74% (n = 145), considered their partners to be unclean during menstruation, and 84.77% (n = 167) of participants did not know how to perform self-testicular examination. More than half of the participants, 55.83% (n = 67), were not in favour of vasectomy and had strong opinions about it; some of those who reportedly knew what a vasectomy involves had some misconceptions.Conclusion: The findings showed that despite participants’ reported knowledge about some reproductive health matters their perceptions were unfavourable towards them. Despite men’s sufficient knowledge about sexually transmitted infections (STIs) and ways to protect themselves against STIs men had limited knowledge about other male and female reproductive health matters.