bluuebunny/crossref_metadata_2025 huggingface dataset:
Bridging the Pathway From the Masters to a Doctoral Program in Higher Education Through Portfolio Learning Assessment
Authors: Baran Mette L. , Jones Janice E.
Published: April 2018

Cardinal Stritch University (CSU) is private Franciscan institution of higher education located in Milwaukee, WI. The university has successfully offered Ph.D. and Ed.D. programs in Leadership for the Advancement of Learning and Service for 20 years. Eight years ago, an additional program was added, namely the Leadership for the Advancement of Learning and Service in Higher Education. Today about 40% of students enrolled are electing this option. A pathway program to this degree will be offered starting in the fall of 2017 with a new Master of Science in Higher Education Student Affairs Leadership. It is proposed that graduates of this program will be able to opt out of up to three doctoral level courses totaling 11 credits if they decide to complete a portfolio learning that demonstrates the accomplishment of program objectives including students' own perceptions of their academic experiences and learning. This is an incentive to matriculate as many of the SAL graduates into the Doctoral Leadership program in higher education saving students resources.
How Prior Learning Assessment Fits Into Today's Education Landscape
Authors: Huggins Susan
Published: April 2018

As defined by the American Council on Education (ACE), prior learning is learning gained outside the college classroom in a variety of settings and through formal and non-formal means, including workplace training, military training and service, independent study, professional certifications, civic activities, or volunteer service. These learning experiences may be equivalent to college-level skills and knowledge and warrant academic credit. Although this definition was coined many years ago, the definition and purpose of prior learning assessment are more pertinent given the changing educational landscape. Today, the proliferation of online and digital learning has opened endless opportunities for learners. With a few clicks on any device, learners can find an immediate solution to their knowledge gap. This increased learning that is occurring outside the walls of formal education increases the need on the assessment process; hence, the growing emphasis on prior learning assessment.
Inclusivity Instead of Exclusivity
Authors: Baker Rose , Passmore David L. , Mulligan Brian Martin
Published: April 2018

Higher education has been perceived as exclusive to those who have the means to purchase the coursework. Many students globally have been alienated from advancing their education, not because of a lack of access, but due to financial barriers. Online education has already transformed the delivery and accessibility of courses for traditional credit toward degrees. MOOCs have been proposed to help bring education to global audiences at little or no cost, creating an inclusive environment for education and skill development. MOOC offerings by colleges provide a method that is disrupting the ways to receive academic credit. Using third-partner vendors to certify knowledge in a similar manner to assessment processes for advanced placement, credit for work experience, and prior learning, MOOC completion is being accepted for college credit. This chapter reviews the extant model, programs, and available outcomes for the MOOC credit acceptance process.
Fostering Effective Learning Community in the Online Classroom
Authors: Dereshiwsky Mary I.
Published: April 2018

Online learning communities are an important aspect of successful virtual learning experiences. They bring opportunities for peer collaboration and sharing of ideas in a globally based classroom unrestricted by time and space. At the same time, online learning community participants may face some challenges of effective communication and collaboration as compared to traditional face-to-face learning environments. The author discusses issues, concerns, and potential solutions with regard to online learning communities in the areas of discussion participation, group work on assignments, faculty concerns, and miscellaneous issues such as technology access. Maximizing the potential of online learning communities will facilitate higher-order learning in the technologically mediated twenty-first century classroom.
A Methodology to Design and Evaluate Agents
Authors: Tamayo-Moreno Silvia , Pérez-Marín Diana
Published: April 2018

Pedagogic conversational agents are computer applications that interact with the students in natural language. They usually focus the dialogue on a certain topic under study. In this chapter, the authors propose the possibility of designing and evaluating agents according to a generic methodology. In particular, the methodology called MEDIE was applied to a study language agent. The main benefit of the study language agent called Lingu is that it is able to generate an infinite number of sentences, and it automatically generates the morphological and syntactical analysis from a given grammar. That way, students can practice with all the sentences they need, receive immediate feedback with automatic evaluation at their own rhythm, and the level of difficulty can be adapted to their particular competence of analysis. To be able to extend Lingu to different schools and needs, MEDIE has been applied as described in this chapter.
Use of Facebook in Primary Teacher Training
Authors: Gómez-Hurtado Inmaculada
Published: April 2018

This chapter presents a study carried out to describe and determine the relevance of the Facebook network as a tool for development of the teaching-learning processes in the teacher-training classroom, and knowledge of the same for use in a research model. This study is based on an analysis of the latest research on the use of social networks in higher education to describe an experiment performed in a group of future primary teachers at a Spanish university in which Facebook was used as a resource to improve the teaching-learning processes. The outcomes point towards a positive evaluation of Facebook as a resource for the creation of collaborative learning communities, improving teaching-learning processes, knowledge construction and social learning, the classroom climate, tutoring among peers and with faculty, foreign-language practice, and digital competence. Among the initial conclusions, the authors highlight the need to demonstrate tools like Facebook to student teachers to ensure their appropriate professional and personal development.
Analysis of Design Alternatives of End-of-Life Products Under Fractional Yields
Authors: Joshi Aditi D. , Gupta Surendra M.
Published: April 2018

In this chapter, an advanced remanufacturing-to-order and disassembly-to-order (ARTODTO) system is considered to evaluate various design alternatives of end-of-life (EOL) products to meet products, components, and materials demands. There are uncertainties about the quantity, quality, and variety of returned EOL products, and these uncertainties lead to fractional disassembly yields. Since the main input to the system is EOL products, their quantities to be acquired is important, and should be determined such that they satisfy all the demands. The designs are evaluated based on four criteria: total profit, procurement cost, purchase cost, and disposal cost using goal programming (GP). A numerical example using EOL dryers is considered to illustrate the implementation of the proposed model.
Sustainable Brand Personality Traits for Business-to-Business Markets
Authors: Avar Fatmanur , Göçer Aysu
Published: April 2018

The impact of globalization and technological advancements on businesses is increasing, making innovation and differentiation essential for survival in competitive markets. Branding is a useful tool for business differentiation, which can be achieved by a strong brand personality. Sustainability, as a strategy integrated with branding, offers the opportunity to gain competitive advantage. Associating sustainability practices with brand personality and integrating them into the brand is important, especially for business-to-business (B2B) brands. However, research on B2B branding is still scarce. Drawing on the tenets of social identity theory, this chapter explains brand personality traits from a sustainability perspective for B2B brands. Based on a series of qualitative and quantitative studies, brand personality traits are identified for B2B markets concerning the environmental, social, and economic pillars of sustainability. This analysis will support B2B managers aiming to promote an image of sustainability for their brands in an increasingly competitive industrial market.
Testing the Unemployment Hysteresis for G-20 Countries
Authors: Yilanci Veli , Sasmaz Mahmut Unsal
Published: April 2018

In this chapter, the authors analyze the validity of unemployment hysteresis for G-20 countries, namely Australia, Brazil, Canada, France, Germany, Indonesia, Italy, Japan, Korea, Mexico, Russia, South Africa, Turkey, United Kingdom, and USA for the 1960–2014 period. For this purpose, they examine the stationarity of the unemployment rates by using ADF unit root test and Fourier ADF (FADF) unit root tests. FADF unit root test is a recently introduced test whose power is not affected by the number, location, and form of the breaks. The results of the tests show that the unemployment hysteresis is valid for some of the countries.
UAPPI
Authors: Rizzo Antonio , Montefoschi Francesco , Caporali Maurizio , Burresi Giovanni
Published: April 2018

This chapter describes the opportunities offered by an extension of MIT App Inventor 2 named UDOO App Inventor (UAPPI). UAPPI aims to facilitate learning in programming the behavior of objects in the physical world (e.g., internet of things). In addition, UAPPI offers the opportunity to experiment with the emerging field of interactive machine learning. Two case studies devoted to different user groups are described to illustrate these opportunities. In the first, dedicated to middle school students, a door is made interactive; in the second, aimed at interaction designers, a light source is controlled by the blink of the eyes and the smile intensity.
From Natural Language to Programming Language
Authors: Liu Xiao , Wu Dinghao
Published: April 2018

Programming remains a dark art for beginners or even professional programmers. Experience indicates that one of the first barriers for learning a new programming language is the rigid and unnatural syntax and semantics. After analysis of research on the language features used by non-programmers in describing problem solving, the authors propose a new program synthesis framework, dialog-based programming, which interprets natural language descriptions into computer programs without forcing the input formats. In this chapter, they describe three case studies that demonstrate the functionalities of this program synthesis framework and show how natural language alleviates challenges for novice programmers to conduct software development, scripting, and verification.
New Classification of Security Requirements for Quantitative Risk Assessment
Authors: Rjaibi Neila , Latifa Ben Arfa Rabai
Published: April 2018

Objective assessment metrics are continuously recommended and a financial analysis of the risk is required in order to justify the security improvements. It is, thus, critically important to validate the security applications as trustworthy and to generalize this research work to other systems. The chapter addresses firstly the problem of quantifying the security of large scale systems, originally the level of e-learning systems. The risk analysis model considers the variability between the system's stakeholders, the requirements, the components and the security attacks. But, in case of large systems, other security challenges are crucially important to be considered. Indeed, our risk analysis model is strengthened to include the development of new requirements classification.
"Eu não sei desenhar": Questionando dons e outras habilidades supostamente excepcionais presentes no ensino de Arte
Authors: Baliscei João Paulo , Lacerda Eva , Teruya Teresa Kazuko
Published: April 2018

As vivências nas disciplinas de Estágio Curricular motivaram-nos a refletir sobre o ensino da técnica de desenho na escola. Nesse artigo, temos por objetivo investigar as maneiras como o ensino de desenho é abordado nos espaços escolares. O problema que orientou essa investigação foi: como as concepções de senso comum que associam as habilidades artísticas a dons ou talentos influenciam o ensino de Artes na Educação Básica? Para discutirmos sobre essa pergunta, elaboramos uma pesquisa de delineamento bibliográfico, na qual investigamos o desenho como prática recorrente nas ações pedagógicas. Em nossas considerações finais, inferimos que a habilidade de desenhar não é advinda de um dom, mas pode ser desenvolvida. Observamos também que as associações do desenho como habilidade inata limitam a criação infantil e reverberam pensamentos simplistas sobre o ensino de Arte.
En Route Critical Care Transfer From a Role 2 to a Role 3 Medical Treatment Facility in Afghanistan
Authors: Staudt Amanda M. , Savell Shelia C. , Biever Kimberly A. , Trevino Jennifer D. , Valdez-Delgado Krystal K. , Suresh Mithun , Gurney Jennifer M. , Shackelford Stacy A. , Maddry Joseph K. , Mann-Salinas Elizabeth A.
Published: April 2018

BACKGROUND

En route care is the transfer of patients requiring combat casualty care within the US military evacuation system. No reports have been published about en route care of patients during transfer from a forward surgical facility (role 2) to a combat support hospital (role 3) for comprehensive care.

OBJECTIVE

To describe patients transferred from a role 2 to a role 3 US military treatment facility in Afghanistan.

METHODS

A retrospective review of data from the Joint Trauma System Role 2 Database was conducted. Patient characteristics were described by en route care medical attendants.

RESULTS

More than one-fourth of patients were intubated at transfer (26.9%), although at transfer fewer than 10% of patients had a base deficit of more than 5 (3.5%), a pH of less than 7.3 (5.2%), an international normalized ratio of more than 2 (0.8%), or temporary abdominal or chest closure (7.4%). The en route care medical attendant was most often a nurse (35.5%), followed by technicians (14.1%) and physicians (10.0%). Most patients (75.3%) were transported by medical evacuation (on rotary-wing aircraft).

CONCLUSION

This is the first comprehensive review of patients transported from a forward surgical facility to a more robust combat support hospital in Afghanistan. Understanding the epidemiology of these patients will inform provider training and the appropriate skill mix for the transfer of postsurgical patients within a combat setting.
Critical Care Performance in a Simulated Military Aircraft Cabin Environment
Authors: McNeill Margaret M.
Published: April 2018

BACKGROUND

Critical Care Air Transport Teams care for 5% to 10% of injured patients who are transported on military aircraft to definitive treatment facilities. Little is known about how the aeromedical evacuation environment affects care.

OBJECTIVES

To determine the effects of 2 stressors of flight, altitude-induced hypoxia and aircraft noise, and to examine the contributions of fatigue and clinical experience on cognitive and physiological performance of the Critical Care Air Transport Team.

METHODS

This repeated measures 2 × 2 × 4 factorial study included 60 military nurses. The participants completed a simulated patient care scenario under aircraft cabin noise and altitude conditions. Differences in cognitive and physiological performance were analyzed using repeated measures analysis of variance. A multiple regression model was developed to determine the independent contributions of fatigue and clinical experience.

RESULTS

Critical care scores (P = .02) and errors and omissions (P = .047) were negatively affected by noise. Noise was associated with increased respiratory rate (P = .02). Critical care scores (P < .001) and errors and omissions (P = .002) worsened with altitude-induced hypoxemia. Heart rate and respiratory rate increased with altitude-induced hypoxemia; oxygen saturation decreased (P < .001 for all 3 variables).

CONCLUSION

In a simulated military aircraft environment, the care of critically ill patients was significantly affected by noise and altitude-induced hypoxemia. The participants did not report much fatigue and experience did not play a role, contrary to most findings in the literature.
Factors That Affect Pain Management in Aeromedical Evacuation: An Ethnographic Approach
Authors: Hatzfeld Jennifer , Serres Jennifer , Dukes Susan
Published: April 2018

BACKGROUND

Pain management is a challenge in the transport setting, but actual factors that influence pain have not been assessed systematically.

OBJECTIVE

To describe the environmental factors and social context that affect pain management in military aeromedical evacuation.

METHODS

Field notes were taken throughout flight, including observational measures of pain, environmental factors, and interactions between the patient and crew. Data collection was completed on 8 missions and 16 patients; common themes were identified that should be considered in the management of pain in aeromedical evacuation.

RESULTS

Communication was a key problem primarily to aircraft noise, the reluctance of patients to speak with crew members while they were wearing headsets, and limited time to assess for pain and provide patient education. Seating and litters appeared to be uncomfortable for ambulatory and litter patients, and preparatory guidance on pain management did not address the stressors of flight or transportation phases. Another compounding factor was the psychological distress, particularly among those leaving a combat zone before the anticipated end of a deployment. Throughout the flight, the military culture of independence, stoicism, and camaraderie also was clearly evident.

CONCLUSIONS

Barriers to communication, comfort, and patient education are well known to transport nurses, but it is important to understand the overall effect they have on the management of pain. Developing solutions to address these factors should be a priority to ensure pain is adequately managed throughout transport.
Resuscitative Endovascular Balloon Occlusion of the Aorta: A Bridge to Flight Survival
Authors: Goforth Carl , Bradley Matthew , Pineda Benilani , See Suzanne , Pasley Jason
Published: April 2018

Trauma endures as the leading cause of death worldwide, and most deaths occur in the first 24 hours after initial injury as a result of hemorrhage. Historically, about 90% of battlefield deaths occur before the injured person arrives at a theater hospital, and most are due to noncompressible hemorrhage of the torso. Resuscitative endovascular balloon occlusion of the aorta is an evolving technique to quickly place a balloon into the thoracic or abdominal aorta to efficiently block blood flow to distal circulation. Maneuvers, such as resuscitative endovascular balloon occlusion of the aorta, to control endovascular hemorrhage offer a potential intervention to control noncompressible hemorrhage. This technique can be performed percutaneously or open in prehospital environments to restore hemodynamic functions and serve as a survival bridge until the patient is delivered to a treatment facility for definitive surgical hemostasis. This article describes the indications, complications, and application of resuscitative endovascular balloon occlusion of the aorta to military and civilian aeromedical transport.
Pressure Injury Development in Patients Treated by Critical Care Air Transport Teams: A Case-Control Study
Authors: Dukes Susan F. , Maupin Genny M. , Thomas Marilyn E. , Mortimer Darcy L.
Published: April 2018

BACKGROUND

The US Air Force transports critically ill patients from all over the world, with transport times commonly ranging from 6 to 11 hours. Few outcome measures have been tracked for these patients. Traditional methods to prevent pressure injuries in civilian hospitals are often not feasible in the military transport environment.

OBJECTIVES

The incidence rate and risk factors are described of en route–related pressure injuries for patients overseen by the Critical Care Air Transport Team.

METHODS

This retrospective, case-control, medical records review investigated risk factors for pressure injury in patients who developed a pressure injury after their transport flight compared with those with no documented pressure injuries.

RESULTS

The pressure injury rate was 4.9%. Between 2008 and 2012, 141 patients in whom pressure injuries developed and who had received care by the team were matched with 141 patients cared for by the team but did not have pressure injury. According to regression analysis, body mass index and 2 or more Critical Care Air Transport Team transports per patient were associated with pressure injury development.

CONCLUSION

Although the pressure injury rate of 4.9% in this cohort of patients is consistent with that reported by civilian critical care units, the rate must be interpreted with caution, because civilian study data frequently represent the entire intensive care unit length of stay. Targeted interventions for patients with increased body mass index and 2 or more critical care air transports per patient may help decrease the development of pressure injury in these patients.
Blocking IL-2 Signal In Vivo with an IL-2 Antagonist Reduces Tumor Growth through the Control of Regulatory T Cells
Authors: Carmenate Tania , Ortíz Yaquelín , Enamorado Michel , García-Martínez Karina , Avellanet Janet , Moreno Ernesto , Graça Luis , León Kalet
Published: April 2018

IL-2 is critical for peripheral tolerance mediated by regulatory T (Treg) cells, which represent an obstacle for effective cancer immunotherapy. Although IL-2 is important for effector (E) T cell function, it has been hypothesized that therapies blocking IL-2 signals weaken Treg cell activity, promoting immune responses. This hypothesis has been partially tested using anti–IL-2 or anti–IL-2R Abs with antitumor effects that cannot be exclusively attributed to lack of IL-2 signaling in vivo. In this work, we pursued an alternative strategy to block IL-2 signaling in vivo, taking advantage of the trimeric structure of the IL-2R. We designed an IL-2 mutant that conserves the capacity to bind to the αβ-chains of the IL-2R but not to the γc-chain, thus having a reduced signaling capacity. We show our IL-2 mutein inhibits IL-2 Treg cell–dependent differentiation and expansion. Moreover, treatment with IL-2 mutein reduces Treg cell numbers and impairs tumor growth in mice. A mathematical model was used to better understand the effect of the mutein on Treg and E T cells, suggesting suitable strategies to improve its design. Our results show that it is enough to transiently inhibit IL-2 signaling to bias E and Treg cell balance in vivo toward immunity.
Tuning T Cell Signaling Sensitivity Alters the Behavior of CD4+ T Cells during an Immune Response
Authors: Milam Ashley A. Viehmann , Bartleson Juliet M. , Donermeyer David L. , Horvath Stephen , Durai Vivek , Raju Saravanan , Yu Haiyang , Redmann Veronika , Zinselmeyer Bernd , White J. Michael , Murphy Kenneth M. , Allen Paul M.
Published: April 2018

Intricate processes in the thymus and periphery help curb the development and activation of autoreactive T cells. The subtle signals that govern these processes are an area of great interest, but tuning TCR sensitivity for the purpose of affecting T cell behavior remains technically challenging. Previously, our laboratory described the derivation of two TCR-transgenic CD4 T cell mouse lines, LLO56 and LLO118, which recognize the same cognate Listeria epitope with the same affinity. Despite the similarity of the two TCRs, LLO56 cells respond poorly in a primary infection whereas LLO118 cells respond robustly. Phenotypic examination of both lines revealed a substantial difference in their surface of expression of CD5, which serves as a dependable readout of the self-reactivity of a cell. We hypothesized that the increased interaction with self by the CD5-high LLO56 was mediated through TCR signaling, and was involved in the characteristic weak primary response of LLO56 to infection. To explore this issue, we generated an inducible knock-in mouse expressing the self-sensitizing voltage-gated sodium channel Scn5a. Overexpression of Scn5a in peripheral T cells via the CD4-Cre promoter resulted in increased TCR-proximal signaling. Further, Scn5a-expressing LLO118 cells, after transfer into BL6 recipient mice, displayed an impaired response during infection relative to wild-type LLO118 cells. In this way, we were able to demonstrate that tuning of TCR sensitivity to self can be used to alter in vivo immune responses. Overall, these studies highlight the critical relationship between TCR–self-pMHC interaction and an immune response to infection.
The Core of an Extended Affine Lie Superalgebra (A Characterization)
Authors: Aramian Rasul , Yousofzadeh Malihe
Published: April 2018

We characterize a class of root graded Lie superalgebras containing a locally finite basic classical simple Lie superalgebra. As a by-product, we characterize the core and the core modulo the center of an extended affine Lie superalgebra whose root system is of finite type

X \neq A(m,n), B(m,n), BC(m,n),C(m,n).
Eigenfunction of the Laplacian as a Degenerate Case of a Function with its Fourier Transform Supported in an Annulus
Authors: Sarkar Rudra P.
Published: April 2018

The aim of this paper is to reach a characterization of the eigenfunction of the Laplace–Beltrami operator as a degenerate case of the inverse Paley–Wiener theorem (for functions whose Fourier transform is supported on a compact annulus) on the rank-1 Riemannian symmetric spaces of noncompact type. The most distinguished prototypes of these spaces are the hyperbolic spaces.
The Fourier Algebra of a Rigid $C^*$-Tensor Category
Authors: Arano Yuki , de Laat Tim , Wahl Jonas
Published: April 2018

Completely positive and completely bounded mutlipliers on rigid

C^*

-tensor categories were introduced by Popa and Vaes. Using these notions, we define and study the Fourier–Stieltjes algebra, the Fourier algebra and the algebra of completely bounded multipliers of a rigid

C^*

-tensor category. The rich structure that these algebras have in the setting of locally compact groups is still present in the setting of rigid

C^*

-tensor categories. We also prove that Leptin’s characterization of amenability still holds in this setting, and we collect some natural observations on property (T).
Experimental Considerations for Modeling Galvanic Corrosion in Aluminum and Its Alloys
Authors: Haque Z. , Clark B.A. , Lillard R.S.
Published: April 2018

In this paper, experimental data are compared for an aluminum/copper galvanic system with model predictions from a commercially available software package. The experimental data consisted of optical profilometry measurements of damage accumulation in a bimetallic Al-Cu strip as a function of immersion time in a chloride environment. Model predictions of corrosion rate were accomplished with software that used a solution of the Laplace equation to determine the potential distribution for a mesh of the system. Current density and, ultimately, corrosion rates were determined with this model by correlating the potential at a mesh point with a current density from the experimental potentiodynamic polarization curves for the materials. Although this is a proven method for systems where the anode material is under activation control, this methodology presents a problem for the case of pitting corrosion, such as Al and its alloys in chloride solution. In the case of pitting corrosion, the surface average current density from the polarization curve (i.e., the couple current density) is not equal to the current density at the base of the pit resulting in a model prediction that underestimates the corrosion rate. To overcome this shortcoming, an alternate method for determining the polarization curve for Al is offered from artificial pit electrodes (pencil electrodes) and model predictions using that method are presented.
Novel Chromium-Free Technologies for the Prevention of Wet Stack Corrosion on Hot Dipped Metallic Coatings: A Review
Authors: Jurak Thomas , Jamali Sina , Zhao Yue , Williams Joe , Saxena Abhishek , Hodges Jason
Published: April 2018

Advances in novel corrosion prevention technologies, including organic-inorganic hybrid sol-gel coatings, ultra violet radiation curable coatings, rare earth metal corrosion inhibitors, and other additions for the fabrication of smart coatings, and their potential application to hot dipped metallic coated steel strip products have been reviewed. Rather than exploring the prevention of atmospheric corrosion as in similar publications in the field, the authors have instead placed emphasis on the feasibility of the technologies for protection against “wet stack corrosion,” also known as wet storage staining. Such corrosion of hot dipped metallic coatings is a common problem in industry, but one rarely explored in academia.
Measurements of aerosol and CCN properties in the Mackenzie River delta (Canadian Arctic) during spring–summer transition in May 2014
Authors: Herenz Paul , Wex Heike , Henning Silvia , Kristensen Thomas Bjerring , Rubach Florian , Roth Anja , Borrmann Stephan , Bozem Heiko , Schulz Hannes , Stratmann Frank
Published: April 2018

Abstract. Within the framework of the RACEPAC (Radiation–Aerosol–Cloud Experiment in
the Arctic Circle) project, the Arctic aerosol, arriving at a ground-based
station in Tuktoyaktuk (Mackenzie River delta area, Canada), was
characterized during a period of 3 weeks in May 2014. Basic meteorological
parameters and particle number size distributions (PNSDs) were observed and
two distinct types of air masses were found. One type were typical Arctic
haze air masses, termed accumulation-type air masses, characterized by a
monomodal PNSD with a pronounced accumulation mode at sizes above
100 nm. These air masses were observed during a period when back
trajectories indicate an air mass origin in the north-east of Canada. The
other air mass type is characterized by a bimodal PNSD with a clear minimum
around 90 nm and with an Aitken mode consisting of freshly formed
aerosol particles. Back trajectories indicate that these air masses, termed
Aitken-type air masses, originated from the North Pacific. In addition, the
application of the PSCF receptor model shows that air masses with their
origin in active fire areas in central Canada and Siberia, in areas of
industrial anthropogenic pollution (Norilsk and Prudhoe Bay Oil Field) and
the north-west Pacific have
enhanced total particle number concentrations (NCN). Generally,
NCN ranged from 20 to 500 cm−3, while cloud
condensation nuclei (CCN) number concentrations were found to cover a range
from less than 10 up to 250 cm−3 for a supersaturation (SS)
between 0.1 and 0.7 %. The hygroscopicity parameter κ of the
CCN was determined to be 0.23 on average and variations in κ were
largely attributed to measurement uncertainties. Furthermore, simultaneous
PNSD measurements at the ground station and on the Polar 6 research
aircraft were performed. We found a good agreement of ground-based PNSDs
with those measured between 200 and 1200 m. During two of the four
overflights, particle number concentrations at 3000 m were found to
be up to 20 times higher than those measured below 2000 m;
for one of these two flights, PNSDs measured above 2000 m showed a
different shape than those measured at lower altitudes. This is indicative of
long-range transport from lower latitudes into the Arctic that can advect
aerosol from different regions in different heights.
Modelling carbonaceous aerosol from residential solid fuel burning with different assumptions for emissions
Authors: Ots Riinu , Heal Mathew R. , Young Dominique E. , Williams Leah R. , Allan James D. , Nemitz Eiko , Di Marco Chiara , Detournay Anais , Xu Lu , Ng Nga L. , Coe Hugh , Herndon Scott C. , Mackenzie Ian A. , Green David C. , Kuenen Jeroen J. P. , Reis Stefan , Vieno Massimo
Published: April 2018

Abstract. Evidence is accumulating that emissions of primary particulate matter (PM) from residential wood and coal combustion in the UK may be underestimated and/or spatially misclassified. In this study, different assumptions for the spatial distribution and total emission of PM from solid fuel (wood and coal) burning in the UK were tested using an atmospheric chemical transport model. Modelled concentrations of the PM components were compared with measurements from aerosol mass spectrometers at four sites in central and Greater London (ClearfLo campaign, 2012), as well as with measurements from the UK black carbon network.The two main alternative emission scenarios modelled were Base4x and combRedist. For Base4x, officially reported PM2.5 from the residential and other non-industrial combustion source sector were increased by a factor of four. For the combRedist experiment, half of the baseline emissions from this same source were redistributed by residential population density to simulate the effect of allocating some emissions to the smoke control areas (that are assumed in the national inventory to have no emissions from this source). The Base4x scenario yielded better daily and hourly correlations with measurements than the combRedist scenario for year-long comparisons of the solid fuel organic aerosol (SFOA) component at the two London sites. However, the latter scenario better captured mean measured concentrations across all four sites. A third experiment, Redist – all emissions redistributed linearly to population density, is also presented as an indicator of the maximum concentrations an assumption like this could yield.The modelled elemental carbon (EC) concentrations derived from the combRedist experiments also compared well with seasonal average concentrations of black carbon observed across the network of UK sites. Together, the two model scenario simulations of SFOA and EC suggest both that residential solid fuel emissions may be higher than inventory estimates and that the spatial distribution of residential solid fuel burning emissions, particularly in smoke control areas, needs re-evaluation. The model results also suggest the assumed temporal profiles for residential emissions may require review to place greater emphasis on evening (including discretionary) solid fuel burning.
Nucleation of nitric acid hydrates in polar stratospheric clouds by meteoric material
Authors: James Alexander D. , Brooke James S. A. , Mangan Thomas P. , Whale Thomas F. , Plane John M. C. , Murray Benjamin J.
Published: April 2018

Abstract. Heterogeneous nucleation of crystalline nitric acid hydrates in
polar stratospheric clouds (PSCs) enhances ozone depletion. However, the
identity and mode of action of the particles responsible for nucleation
remains unknown. It has been suggested that meteoric material may trigger
nucleation of nitric acid trihydrate (NAT, or other nitric acid phases), but
this has never been quantitatively demonstrated in the laboratory. Meteoric
material is present in two forms in the stratosphere: smoke that results
from the ablation and re-condensation of vapours, and fragments that result
from the break-up of meteoroids entering the atmosphere. Here we show that
analogues of both materials have a capacity to nucleate nitric acid hydrates.
In combination with estimates from a global model of the amount of meteoric
smoke and fragments in the polar stratosphere we show that meteoric material
probably accounts for NAT observations in early season polar stratospheric
clouds in the absence of water ice.
Separating the role of direct radiative heating and photolysis in modulating the atmospheric response to the 11-year solar cycle forcing
Authors: Bednarz Ewa M. , Maycock Amanda C. , Braesicke Peter , Telford Paul J. , Abraham N. Luke , Pyle John A.
Published: April 2018

Abstract. The atmospheric response to the 11-year solar cycle forcing is separated into the contributions from changes in direct radiative heating and photolysis rates using specially designed sensitivity simulations with the UM-UKCA chemistry-climate model. We find that contributions from changes in direct heating and photolysis rates are important for determining the shortwave heating, temperature and ozone responses to the solar cycle forcing. The combined effects of the processes are found to be largely additive in the tropics but non-additive in the high latitudes, in particular in the Southern Hemisphere (SH) during the dynamically active season. We find marked differences in the changes in magnitude and vertical structure of shortwave heating rates gradients across the SH in austral winter, thereby highlighting a potential sensitivity of the polar dynamical response to the altitude of the anomalous radiative tendencies. In addition, our results indicate that, in contrast to the original mechanism proposed in the literature, the solar-induced changes in the horizontal shortwave heating rate gradients not only in autumn/early winter, but throughout the dynamically active season are important for modulating the dynamical response. In spring, these gradients are strongly influenced by the shortwave heating anomalies at higher southern latitudes, which are closely linked to the concurrent changes in ozone. Our results suggest that solar-induced changes in ozone, both in the tropics/mid-latitudes and the polar regions, are important for modulating the SH dynamical response to the 11-year solar cycle. In addition, the markedly non-additive character of the SH polar vortex response simulated in austral spring highlights the need for consistent model implementation of the solar cycle forcing in both the radiative heating and photolysis schemes.
Description and applications of a mobile system performing on-road
aerosol remote sensing and in situ measurements
Authors: Popovici Ioana Elisabeta , Goloub Philippe , Podvin Thierry , Blarel Luc , Loisil Rodrigue , Unga Florin , Mortier Augustin , Deroo Christine , Victori Stéphane , Ducos Fabrice , Torres Benjamin , Delegove Cyril , Choël Marie , Pujol-Söhne Nathalie , Pietras Christophe
Published: April 2018

Abstract. The majority of ground-based aerosols observations are limited to fixed locations, narrowing the knowledge on their spatial variability. In order to overcome this issue, a compact Mobile Aerosol Monitoring System (MAMS) was developed to explore the aerosol vertical and spatial variability. This mobile laboratory is equipped with a micropulse lidar, a sun-photometer and an aerosol spectrometer. It is distinguished by other transportable platforms through its ability to perform on-road measurements and its unique feature lies in the sun-photometer capable to track the sun during motion. The system presents a great flexibility, being able to respond quickly in case of sudden aerosol events such as pollution episodes, dust, fire or volcano outbreaks. On-road mapping of aerosol physical parameters such as attenuated aerosol backscatter, aerosol optical depth, particle number and mass concentration and size distribution is achieved through the MAMS. The performance of remote sensing instruments on-board has been evaluated through intercomparison with instruments in reference networks (i.e. AERONET and EARLINET), showing that the system is capable of providing high quality data. This also illustrates the application of such system for instrument intercomparison field campaigns. Applications of the mobile system have been exemplified through two case studies in northern France. MODIS AOD data was compared to ground-based mobile sun-photometer data. A good correlation was observed with R2 of 0.76, showing the usefulness of the mobile system for validation of satellite-derived products. The performance of BSC-DREAM8b dust model has been tested by comparison of results from simulations to the lidar-sun-photometer derived extinction coefficient and mass concentration profiles. The comparison indicated that observations and model are in good agreement in describing the vertical variability of dust layers. Moreover, on-road measurements of PM10 were compared with modelled PM10 concentrations and with ATMO Hauts-de-France and AIRPARIF air quality in situ measurements, presenting an excellent agreement in horizontal spatial representativity of PM10. This proves a possible application of mobile platforms for evaluating the chemistry-models performances.
WIRA-C: A compact 142-GHz-radiometer for continuous middle-atmospheric wind measurements
Authors: Hagen Jonas , Murk Axel , Rüfenacht Rolf , Khaykin Sergey , Hauchecorne Alain , Kämpfer Niklaus
Published: April 2018

Abstract. Ground-based microwave wind radiometry provides a method to measure horizontal wind speeds at altitudes between 35 and 75 km as it has been shown by various previous studies. No other method is capable of continuously delivering wind measurements in this altitude region. In this paper, we present the WIRA-C (WInd Radiometer for Campaigns) instrument that observes the 142.17504 GHz rotational transition line of ozone with a high spectral resolution using a low noise single side band heterodyne receiver. Because the emitting molecules are drifting with the wind, the line is Doppler shifted. Together with the pressure broadening effect, this allows the retrieval of altitude resolved wind profiles. The novel WIRA-C instrument represents the newest development in microwave wind radiometry. The main improvements include the compact structure, lower noise and an advanced retrieval setup. This paper describes the instrument and the data processing with a focus on the retrieval that takes into account a three-dimensional atmosphere and has never been used in ground-based radiometry before. The retrieval yields profiles of horizontal wind speeds with a 12 hour time resolution and a vertical resolution of 10 km for zonal and 10 to 15 km for meridional wind speeds. We give an error estimate that accounts for the thermal noise on the measured spectra and additionally estimate systematic errors using Monte Carlo methods. WIRA-C has been continuously measuring horizontal wind speeds since one year at the Maïdo observatory on La Réunion Island (21.4° S, 55.9° E). We present the time series of this campaign and compare our measurements to model data from the European Centre for Medium-range Weather Forecasts (ECMWF) and coincident measurements of the co-located Rayleigh-Mie Doppler wind lidar. We find a good agreement between our measurements and the ECMWF operational analysis for the time series, where many features are present in both datasets. The wind profiles of the coincident WIRA-C and lidar observations are consistent and agree within their respective uncertainties for the lidar measurements with long integration times.
Simulation study for the Stratospheric Inferred Winds (SIW)
sub-millimeter limb sounder
Authors: Baron Philippe , Murtagh Donal , Eriksson Patrick , Mendrok Jana , Ochiai Satoshi , Pérot Kristell , Sagawa Hideo , Suzuki Makoto
Published: April 2018

Abstract. Stratospheric Inferred Winds (SIW) is a Swedish mini sub-millimeter limb sounder selected for the 2nd InnoSat platform launch planned near 2022. It is intended to fill the altitude gap between 30–70 km in atmospheric wind measurements and also aims at pursuing the limb observations of temperature and key atmospheric constituents between 10–90 km when current satellite missions are probably stopped. Line-of-sight winds are retrieved from the Doppler shift of the emission lines introduced by 5 the wind field. Observations will be performed with two antennas pointing toward the limb with perpendicular directions to reconstruct the 2-D horizontal wind vector. Each antenna has a vertical field of view of 5 km. The chosen spectral band near 655 GHz contains a dense group of strong O3 lines suitable for exploiting the small wind information in stratospheric spectra. Using both sidebands of the heterodyne receiver, a large number of chemical species will be measured including O3-isopotologues, H2O, HDO, HCl, ClO, N2O, HNO3, NO, NO2, HCN, CH3CN and HO2. This paper presents the simulation study for assessing the measurement performances. The line-of-sight winds are retrieved between 30–90 km with the best sensitivity between 35–70 km where the precision (1-sigma) is 5–10 m s−1 for a single scan. Similar performances can be obtained during day and night conditions except in the lower mesosphere where the photo-dissociation of O3 in day-time reduces the sensitivity by 50 % near 70 km. Profiles of O3, H2O and temperature are retrieved with a high precision up to 50 km (
Abyssal plain hills and internal wave turbulence
Authors: van Haren Hans
Published: April 2018

Abstract. A 400-m long array with 201 high-resolution NIOZ temperature sensors was deployed above a northeast-equatorial Pacific hilly abyssal plain for 2.5 months. The sensors sampled at 1 Hz, the lowest was at 7 m above the bottom "mab". The aim was to study internal waves and turbulent overturning away from large-scale ocean topography. Topography consisted of moderate, a few 100 m elevated hills, providing a mean bottom slope of one-third of that found at the Mid-Atlantic Ridge (on 2 km horizontal scales). In contrast with observations over large-scale topography like guyots, ridges and continental slopes, the present data showed a well-defined near-homogeneous "bottom-boundary layer" extending between
North Atlantic subpolar gyre along predetermined ship tracks since 1993: a
monthly dataset of surface temperature, salinity, and density
Authors: Reverdin Gilles , Valdimarsson Hedinn , Alory Gael , Diverres Denis , Bringas Francis , Goni Gustavo , Heilmann Lars , Chafik Leon , Szekely Tanguy , Friedman Andrew R.
Published: April 2018

Abstract. We present a binned product of sea surface temperature, sea surface salinity and sea surface density data in the North Atlantic subpolar gyre for the 1993–2017 that resolves seasonal variability along specific ship routes (doi:10.6096/SSS-BIN-NASG). The characteristics of this product are described and validated through comparisons to other monthly products. Data presented in this work was collected in regions crossed by two predetermined ship transects, between Denmark and western Greenland (AX01) and between Iceland, Newfoundland, and the northeastern USA (AX02). The analysis and the strong correlation between successive seasons indicate that in large parts of the subpolar gyre, the binning approach is robust and resolves the seasonal time scales, in particular after 1997 and in regions away from the continental shelf. Prior to 2002, there was no winter sampling over the west Greenland shelf. Variability in sea surface salinity increases towards Newfoundland south of 54° N, as well as in the western Iceland Basin along 59° N. Variability in sea surface temperature presents less spatial structure with an increase westward and towards Newfoundland. The contribution of temperature variability to density dominates in the eastern part of the gyre, whereas the contribution of salinity variability dominates in the southwestern part along AX02.