bluuebunny/crossref_metadata_2025 huggingface dataset:
Kainic Acid Impairs the Memory Behavior of APP23 Mice by Increasing Brain Amyloid Load through a Tumor Necrosis Factor-α-Dependent Mechanism
Authors: Ruan Yang , Guo Shi-Jie , Wang Xu , Dong Dong , Shen Dong-Hui , Zhu Jie , Zheng Xiang-Yu
Published: May 2018

Kainic acid (KA) was recently identified as an epileptogenic and neuroexcitotoxic agent that is responsible for inducing learning and memory deficits in various neurodegenerative diseases, such as Alzheimer’s disease (AD). However, the mechanism by which KA acts upon AD remains unclear. To this end, we presently investigated the roles of KA in processing amyloid-β protein precursor (AβPP) and amyloid-β protein (Aβ) loads during the course of AD development and progression. Specifically, KA treatment clearly caused the upregulation of tumor necrosis factor α (TNF-α) via activation of the PI3-K/AKT, ERK1/2, and p65 pathways in glial cells. TNF-α secreted from glial cells was then found to be responsible for stimulating the expression of BACE-1 and PS1/2, which resulted in the production and deposition of Aβ in neurons. Finally, the accumulation and aggregation of Aβ lead to the cognitive decline of APP23 mice. These results indicate that KA accelerates the progression of AD by inducing the crosstalk between glial cells and neurons.
Revolutionizing Our Understanding of AGN Feedback and its Importance to Galaxy Evolution in the Era of the Next Generation Very Large Array
Authors: Nyland K. , Harwood J. J. , Mukherjee D. , Jagannathan P. , Rujopakarn W. , Emonts B. , Alatalo K. , Bicknell G. V. , Davis T. A. , Greene J. E. , Kimball A. , Lacy M. , Lonsdale Carol , Lonsdale Colin , Maksym W. P. , Molnár D. C. , Morabito L. , Murphy E. J. , Patil P. , Prandoni I. , Sargent M. , Vlahakis C.
Published: May 2018

Energetic feedback by active galactic nuclei (AGNs) plays an important evolutionary role in the regulation of star formation on galactic scales. However, the effects of this feedback as a function of redshift and galaxy properties such as mass, environment, and cold gas content remain poorly understood. The broad frequency coverage (1 to 116 GHz), high sensitivity (up to ten times higher than the Karl G. Jansky Very Large Array), and superb angular resolution (maximum baselines of at least a few hundred kilometers) of the proposed next-generation Very Large Array (ngVLA) are uniquely poised to revolutionize our understanding of AGNs and their role in galaxy evolution. Here, we provide an overview of the science related to AGN feedback that will be possible in the ngVLA era and present new continuum ngVLA imaging simulations of resolved radio jets spanning a wide range of intrinsic extents. We also consider key computational challenges and discuss exciting opportunities for multiwavelength synergy with other next-generation instruments, such as the Square Kilometer Array and the James Webb
Space Telescope. The unique combination of high-resolution, large collecting area, and wide frequency range will enable significant advancements in our understanding of the effects of jet-driven feedback on sub-galactic scales, particularly for sources with extents of a few parsec to a few kiloparsec, such as young and/or lower-power radio AGNs, AGNs hosted by low-mass galaxies, radio jets that are interacting strongly with the interstellar medium of the host galaxy, and AGNs at high redshift.
Bubbles in Titan’s Seas: Nucleation, Growth, and RADAR Signature
Authors: Cordier Daniel , Liger-Belair Gérard
Published: May 2018

In the polar regions of Titan, the main satellite of Saturn, hydrocarbon seas have been discovered by the Cassini–Huygens mission. RADAR observations have revealed surprising and transient bright areas over the Ligeia Mare surface. As suggested by recent research, bubbles could explain these strange features. However, the nucleation and growth of such bubbles, together with their RADAR reflectivity, have never been investigated. All of these aspects are critical to an actual observation. We have thus applied the classical nucleation theory to our context, and we developed a specific radiative transfer model that is appropriate for bubble streams in cryogenic liquids. According to our results, the sea bed appears to be the most plausible place for the generation of bubbles, leading to a signal comparable to observations. This conclusion is supported by thermodynamic arguments and by RADAR properties of a bubbly column. The latter are also valid in the case of bubble plumes, due to gas leaking from the sea floor.
On the Rate and on the Gravitational Wave Emission of Short and Long GRBs
Authors: Ruffini R. , Rodriguez J. , Muccino M. , Rueda J. A. , Aimuratov Y. , Almeida U. Barres de , Becerra L. , Bianco C. L. , Cherubini C. , Filippi S. , Gizzi D. , Kovacevic M. , Moradi R. , Oliveira F. G. , Pisani G. B. , Wang Y.
Published: May 2018

On the ground of the large number of gamma-ray bursts (GRBs) detected with cosmological redshift, we classified GRBs in seven subclasses, all with binary progenitors which emit gravitational waves (GWs). Each binary is composed of combinations of carbon–oxygen cores (COcore), neutron stars (NSs), black holes (BHs), and white dwarfs (WDs). The long bursts, traditionally assumed to originate from a BH with an ultrarelativistic jetted emission, not emitting GWs, have been subclassified as (I) X-ray flashes (XRFs), (II) binary-driven hypernovae (BdHNe), and (III) BH–supernovae (BH–SNe). They are framed within the induced gravitational collapse paradigm with a progenitor COcore–NS/BH binary. The SN explosion of the COcore triggers an accretion process onto the NS/BH. If the accretion does not lead the NS to its critical mass, an XRF occurs, while when the BH is present or formed by accretion, a BdHN occurs. When the binaries are not disrupted, XRFs lead to NS–NS and BdHNe lead to NS–BH. The short bursts, originating in NS–NS, are subclassified as (IV) short gamma-ray flashes (S-GRFs) and (V) short GRBs (S-GRBs), the latter when a BH is formed. There are (VI) ultrashort GRBs (U-GRBs) and (VII) gamma-ray flashes (GRFs) formed in NS–BH and NS–WD, respectively. We use the occurrence rate and GW emission of these subclasses to assess their detectability by Advanced LIGO-Virgo, eLISA, and resonant bars. We discuss the consequences of our results in view of the announcement of the LIGO/Virgo Collaboration of the source GW 170817 as being originated by an NS–NS.
Whip: Communicate and Test What to Expect from Data
Authors: Van Hoey Stijn , Desmet Peter
Published: May 2018

The ability to communicate and assess the quality and fitness for use of data is crucial to ensure maximum utility and re-use. Data consumers have certain requirements for the data they seek and need to be able to check if a data set conforms with these requirements. Data publishers aim to provide data with the highest possible quality and need to be able to identify potential errors that can be addressed with the available information at hand. The development and adoption of data publication guidelines is one approach to define and meet those requirements. However, the use of a guideline, the mapping decisions, and the requirements a dataset is expected to meet, are generally not communicated with the provided data. Moreover, these guidelines are typically intended for humans only.

In this talk, we will present 'whip': a proposed syntax for data specifications. With whip, one can define column-based constraints for tabular (tidy) data using a number of rules, e.g. how data is structured following Darwin Core, how a term uses controlled vocabulary values, or what the expected minimum and maximum values are. These rules are human- and machine-readable, which communicates the specifications, and allows to automatically validate those in pipelines for data publication and quality assessment, such as Kurator. Whip can be formatted as a (yaml) text file that can be provided with the published data, communicating the specifications a dataset is expected to meet. The scope of these specifications can be specific to a dataset, but can also be used to express expected data quality and fitness for use of a publisher, consumer or community, allowing bottom-up and top-down adoption. As such, these specifications are complementary to the core set of data quality tests as currently under development by the TDWG Biodiversity Data Quality Task 2 Group 2. Whip rules are currently generic, but more specific ones can be defined to address requirements for biodiversity information.
Digital Object Cloud for linking natural science collections information; The case of DiSSCo
Authors: Koureas Dimitrios , Addink Wouter , Hardisty Alex
Published: May 2018

DiSSCo(The Distributed System of Scientific Collections) is a Research Infrastructure (RI) aiming at providing unified physical (transnational), remote (loans) and virtual (digital) access to the approximately 1.5 billion biological and geological specimens in collections across Europe. DiSSCo represents the largest ever formal agreement between natural science museums (114 organisations across 21 European countries). With political and financial support across 14 European governments and a robust governance model DiSSCo will deliver, by 2025, a series of innovative end-user discovery, access, interpretation and analysis services for natural science collections data.

As part of DiSSCo's developing data model, we evaluate the application of Digital Objects (DOs), which can act as the centrepiece of its architecture. DOs have bit-sequences representing some content, are identified by globally unique persistent identifiers (PIDs) and are associated with different types of metadata. The PIDs can be used to refer to different types of information such as locations, checksums, types and other metadata to enable immediate operations. In the world of natural science collections, currently fragmented data classes (inter alia genes, traits, occurrences) that have derived from the study of physical specimens, can be re-united as parts in a virtual container (i.e., as components of a Digital Object). These typed DOs, when combined with software agents that scan the data offered by repositories, can act as complete digital surrogates of the physical specimens.

In this paper we:

investigate the architectural and technological applicability of DOs for large scale data RIs for bio- and geo-diversity,

identify benefits and challenges of a DO approach for the DiSSCo RI and

describe key specifications (incl. metadata profiles) for a specimen-based new DO type.
Which questions drive the Mapping and Assessment of Ecosystems and their Services under Action 5 of the EU Biodiversity Strategy?
Authors: Maes Joachim , Liekens Inge , Brown Claire
Published: May 2018

Action 5 of the European Union's Biodiversity Strategy to 2020 asks that Member States map and assess the state of ecosystems and their services in their national territory. Policymakers and stakeholders of these countries frequently ask why this work is necessary. This article shows that this question can be broken down into a number of specific questions which, in turn, bring specific requests for knowledge and guidance to the surface. This paper develops a typology of questions and identifies the following five categories: knowledge requests, policy support questions, questions on resources and responsibilities, application questions and technical and methodological guidance questions. Next, this typology of questions is framed in an adaptive policy cycle and coupled to a set of available solutions.
Le quotidien du psychanalyste
Authors: André Jacques
Published: May 2018

L’auteur propose une réflexion en appui sur sa pratique en cabinet sur ce qui fait le quotidien d’une cure analytique. Le quotidien du psychanalyste c’est en effet d’abord un lieu, le cabinet, et un cadre, le setting analytique. Ce quotidien c’est aussi deux figures inverses : la répétition et l’imprévu. La première menace l’analyse de l’interminable, le second promet au contraire l’ouverture sur l’inconnu et le changement.
Sur les rituels communs à toute institution psychiatrique
Authors: Kecskeméti Sophie
Published: May 2018

Après le passage en revue des caractéristiques générales de toute institution psychiatrique, l’auteure examine la façon dont celles-ci se cristallisent sous la forme d’un certain nombre de rituels, ainsi que leur fragilisation actuelle. Un exemple des rites d’une institution pour adolescents est donné, suivi de la narration d’un cas clinique. L’après-coup de ce cas permet de mettre en évidence l’effet thérapeutique à long terme des rites et des rituels qui font la vie quotidienne en institution, même lorsque les soins ont en partie échoué. La question des limites est discutée.
La dignité au quotidien ou portrait d’un soignant fatigué un après-midi pluvieux de novembre…
Authors: Fiat Éric
Published: May 2018

Si la dignité est de nos jours la valeur essentielle du soin, elle recouvre des significations si différentes qu’il est parfois difficile au soignant de savoir ce que veut dire « respecter la dignité de la personne malade ». L’auteur propose, en appui sur une réflexion philosophique, que deux sens essentiels de la dignité soient distingués : ­l’ontologique (une dignité qui ne peut se perdre) d’une part, la posturale (qui elle peut être menacée par la maladie, particulièrement psychique) d’autre part. Veiller au quotidien sur ces deux dignités est sans doute chose assez facile le jour où la rencontre du soignant et du soigné est celle d’une forme et d’une gratitude ; mais qu’en est-il le jour où cette rencontre est celle d’une fatigue et d’une agressive souffrance ? Mais si la fatigue est le démon mesquin de la quotidienneté, rend-elle totalement impossible le respect de la dignité des patients ? L’auteur fait le pari que non, en faisant l’éloge de l’habitude et de la douce répétition des jours…
Impasses de l’individualisme contemporain
Authors: Servant Benoît
Published: May 2018

La place donnée aujourd’hui à la nourriture et à la dignité dans les institutions de soins reflète pour l’auteur le déni contemporain de l’interdépendance et de la précarité humaines. De même, l’éloge du banal ne refléterait-il pas le déni de toute inégalité ? Et les problèmes soulevés dans la table ronde ne sont-ils pas dès lors à interpréter comme retour du dénié ?
Lean approach in knowledge work
Authors: Kropsu-Vehkapera Hanna , Isoherranen Ville
Published: May 2018

Purpose: Knowledge work productivity is a key area of improvement for many organisations. Lean approach is a sustainable way to achieve operational excellence and can be applied in many areas. The purpose of this novel study is to examine the potential of using lean approach for improving knowledge work practices.Design/methodology/approach: A systematic literature review has been carried out to study how lean approach is realised in knowledge work. The research is conceptual in nature and draws upon earlier research findings.Findings: This study shows that lean studies’ in knowledge work is an emerging research area. This study documents the methods and practices implemented in knowledge work to date, and presents a knowledge work continuum, which is an essential framework for effective lean approach deployment and to frame future research focus in knowledge work productivity.Research limitations/implications: This study structures the concept of knowledge work and outlines a concrete concept derived from earlier literature. The study summarises the literature on lean in knowledge work and highlights, which methods are used. More research is needed to understand how lean can be implemented in complex knowledge work environment and not only on the repetitive knowledge work. The limitations of this research are due to the limited availability of previous research.Practical implications: To analyse the nature of knowledge work, we implicate the areas where lean methods especially apply to improving knowledge work productivity. When applying lean in knowledge work context the focus should be using the people better and improving information flow.Originality/value: This study focuses on adapting lean methods into a knowledge work context and summarises earlier research done in this field. The study discusses the potential to improve knowledge work productivity by implementing lean methods and presents a unique knowledge work continuum to frame previous research and give focus for future research.
La adaptación de la fiscalidad aduanera a los intereses repobladores, comerciales y políticos. Andalucía, 1241-1550
Authors: González Arce José Damián
Published: May 2018

El presente trabajo tiene por objetivo analizar la política regia de exenciones y reducciones del almojarifazgo aduanero en las tierras andaluzas durante la baja Edad Media; que generalmente afectaban, además, a otros derechos de paso, como el portazgo, similar al demandarse también por la entrada y salida de las poblaciones, el diezmo y medio diezmo de lo morisco, en este caso sobre las importaciones y exportaciones con Granada, y otros marginales, como rodas, castillerías, peajes... La concesión de estas franquezas nos desvela cuáles eran los intereses económicos y políticos de los monarcas en cada período y coyuntura. Mientras que su reducción o supresión ponen de manifiesto los cambios habidos con el tiempo, que hicieron desaparecer o disminuir las causas de la despoblación, inseguridad fronteriza o atraso económico que habían motivado las exoneraciones. Para ello ha sido utilizada la documentación fiscal conservada en el Archivo General de Simancas, así como en los municipales de Sevilla, Córdoba, Carmona o Jerez. Finalmente, se concluye que tales ventajas sirvieron a un propósito repoblador y que solo las poblaciones más expuestas o estratégicas fueron capaces de mante nerlas más o menos intactas con el paso de los años, sobre todo cuando eran además puntos clave para el comercio exterior.
Genèse éditoriale de Dan Yack
Authors: Pidoux Sylvestre
Published: May 2018

En 1946, Blaise Cendrars réunit en un seul volume, intitulé Dan Yack, deux romans qu’il avait déjà publiés en 1929, Le Plan de l’Aiguille et Les Confessions de Dan Yack. Le statut de chacun des deux romans change de 1929 à 1946, lorsqu’ils deviennent deux parties d’un seul volume. Cette étude analyse les enjeux de ce geste éditorial. Elle interroge dans un premier temps les conditions d’identification des deux tomes de 1929 au seul volume de 1946 avant d’analyser la part prise par la communication publique des textes dans la genèse du volume de 1946.
L’espace du style : sur les trois versions d’Éperons (1973, 1976, 1978) de Jacques Derrida
Authors: Wiser Antonin
Published: May 2018

L’article se propose de lire les trois versions d’Éperons de Jacques Derrida, publiées respectivement en 1973, 1976 et 1978. En examinant le travail de réécriture parfois très fin auquel procéda le philosophe, on verra s’inscrire une distance qui redouble et déplace le propos de son texte. En elle s’ouvre un espace qu’on reconnaîtra comme celui du style – opération de découpe de ce stylet que Derrida emprunte à Nietzsche –, dont le lieu, si c’en est encore un, n’est autre que l’écart entre les différentes versions.
Measuring and profiling financial literacy in South Africa
Authors: Nanziri Elizabeth L. , Leibbrandt Murray
Published: May 2018

Background: Microeconomic theories of financial behaviour tend to assume that consumers possess financial skills necessary to undertake related financial decisions. Aim and setting: We investigated this assumption by exploring the distribution of financial literacy among South Africans. Method: In the absence of a standard measure, a financial literacy index was constructed for the country using data collected on attitudes (towards), access to and use of financial services over the period 2005–2009. In a multivariate regression analysis, we used the index to examine the extent to which differences in financial literacy correlate with demographic and economic characteristics. Results: The index revealed substantial variation in financial literacy by age, education, province and race. Overall, demographic characteristics contributed up to 10% of the financial literacy differences among individuals in South Africa. Conclusion: These results can be used to guide policy makers where to place more emphasis in terms of financial education for South Africans.
Preliminary Validity Evidence for a Milestones-Based Rating Scale for Chart-Stimulated Recall
Authors: Reddy Shalini T. , Tekian Ara , Durning Steven J. , Gupta Shanu , Endo Justin , Affinati Brenda , Park Yoon Soo
Published: May 2018

Background 

Minimally anchored Standard Rating Scales (SRSs), which are widely used in medical education, are hampered by suboptimal interrater reliability. Expert-derived frameworks, such as the Accreditation Council for Graduate Medical Education (ACGME) Milestones, may be helpful in defining level-specific anchors to use on rating scales.

Objective 

We examined validity evidence for a Milestones-Based Rating Scale (MBRS) for scoring chart-stimulated recall (CSR).

Methods 

Two 11-item scoring forms with either an MBRS or SRS were developed. Items and anchors for the MBRS were adapted from the ACGME Internal Medicine Milestones. Six CSR standardized videos were developed. Clinical faculty scored videos using either the MBRS or SRS and following a randomized crossover design. Reliability of the MBRS versus the SRS was compared using intraclass correlation.

Results 

Twenty-two faculty were recruited for instrument testing. Some participants did not complete scoring, leaving a response rate of 15 faculty (7 in the MBRS group and 8 in the SRS group). A total of 529 ratings (number of items × number of scores) using SRSs and 540 using MBRSs were available. Percent agreement was higher for MBRSs for only 2 of 11 items—use of consultants (92 versus 75, P = .019) and unique characteristics of patients (96 versus 79, P = .011)—and the overall score (89 versus 82, P < .001). Interrater agreement was 0.61 for MBRSs and 0.51 for SRSs.

Conclusions 

Adding milestones to our rating form resulted in significant, but not substantial, improvement in intraclass correlation coefficient. Improvement was inconsistent across items.
X + Y = Time for QI: Meaningful Engagement of Residents in Quality Improvement During the Ambulatory Block
Authors: Johnson Krista M. , Fiordellisi Wendy , Kuperman Ethan , Wickersham Alexis , Kuehn Carly , Kamath Aparna , Szot Joseph , Suneja Manish
Published: May 2018

Background 

Meaningful resident engagement in quality improvement (QI) remains challenging. Barriers include a lack of time and of faculty with QI expertise. We leveraged our internal medicine (IM) residency program's adoption of an “X” (inpatient rotations) plus “Y” (ambulatory block) schedule to implement a QI curriculum for all residents during their ambulatory block.

Objective 

We sought to engage residents in interprofessional QI, improve residents' QI confidence and knowledge and application to practice, and create opportunities for QI scholarship.

Methods 

In July 2015, the program provided dedicated time for QI in the ambulatory block. All categorical IM residents and 11 voluntary faculty mentors were divided into 10 teams based on clinic site and “Y” block schedule. Teams participated in resident-led, interprofessional ambulatory QI projects. Resident QI knowledge and confidence were assessed before the curriculum and 11 months after using the Quality Improvement Knowledge Application Tool–Revised (QIKAT-R) and surveys. QI project implementation and scholarship were tracked.

Results 

All categorical residents (N = 81) participated. Residents reported increased confidence in all QI skills, and they demonstrated increased knowledge, with mean QIKAT-R paired scores improving from 15.8 ± 4.6 to 19.1 ± 5.9 (n = 45 pairs, P < .001). A total of 9 of 10 teams implemented process changes, and 6 team project improvements have been sustained.

Conclusions 

This ongoing curriculum engaged IM and IM-psychiatry residents in QI during their ambulatory block using volunteer clinic faculty mentors. Residents demonstrated improved QI confidence and knowledge. The majority of resident projects were sustained and generated scholarship.
Urban source term estimation for mercury using a boundary-layer budget method
Authors: Denzler Basil , Bogdal Christian , Kern Cyrill , Tobler Anna , Huo Jing , Hungerbühler Konrad
Published: May 2018

Abstract. Mercury is a heavy metal of particular concern due to its adverse effects on the human health and the environment. Recognizing this problem, the UN Minamata Convention on Mercury was recently adopted, where signatory countries agreed to reduce anthropogenic mercury emissions. To evaluate the effectiveness of the convention, quantitative knowledge on mercury emissions is crucial. So far, bottom-up approaches have successfully been applied to quantify mercury emission – especially for point sources. Distributed sources make up for a large share of the emission, however, they are still poorly characterized. Here, we present a top-down approach to estimate mercury emissions based on atmospheric measurements in the city of Zurich, Switzerland. While monitoring the atmospheric mercury concentrations during inversion periods in Zurich, we were able to relate the concentration increase to the mercury emission strength of the city using a box model. By the means of this boundary-layer budget approach, we succeeded to narrow down the emissions of Zurich to range between 41 ± 8 kg/a (upper bound) and 24 ± 8 kg/a (lower bound). Thereby, we could quantify emissions from mixed, diffuse and point like sources and derive an annual mercury per capita emission of 0.06 to 0.10 g/a. The approach presented here has the potential to support authorities in setting up inventories and to validate emission estimations derived from the commonly applied bottom-up approaches. Furthermore, our method is applicable to other compounds and to a wide range of cities or other areas, where sources or as well sinks for mercury and other atmospheric pollutants are presumed.
Elucidating real-world vehicle emission factors from mobile
measurements over a large metropolitan region: a focus on isocyanic
acid, hydrogen cyanide, and black carbon
Authors: Wren Sumi N. , Liggio John , Han Yuemei , Hayden Katherine , Lu Gang , Mihele Cris M. , Mittermeier Richard L. , Stroud Craig , Wentzell Jeremy J. B. , Brook Jeffrey R.
Published: May 2018

Abstract. A mobile laboratory equipped with state-of-the-art gaseous and particulate instrumentation was deployed across the Greater Toronto Area during two seasons. A high-resolution time-of-flight mass spectrometer (HR-TOF-CIMS) measured isocyanic acid (HNCO) and hydrogen cyanide (HCN), and a high-sensitivity laser-induced incandescence (HS-LII) instrument measured black carbon (BC). Results indicate that on-road vehicles are a clear source of HNCO and HCN, and that their impact is more pronounced in the winter, when influences from biomass burning and secondary photochemistry are weakest. Plume-based and time-based algorithms were developed to calculate fleet-average vehicle emission factors (EF); the algorithms were found to yield comparable results, depending on the pollutant identity. With respect to literature EFs for benzene, toluene, C2 benzene (sum of m,p,o-xylenes and ethylbenzene), nitrogen oxides, particle number concentration (PN), and black carbon, the calculated EFs were characteristic of a relatively clean vehicle fleet dominated by light-duty vehicles. Our fleet-average EF for BC (median: 25 mg kgfuel−1, interquartile range: 10–76 mg kgfuel−1) suggests that overall vehicular emissions of BC have decreased over time. However, the distribution of EFs indicates that a small proportion of high-emitters continue to contribute disproportionately to total BC emissions. We report the first fleet-average EF for HNCO (median: 2.3 mg kgfuel−1, interquartile range: 1.4–4.2 mg kgfuel−1) and HCN (median: 0.52 mg kgfuel−1, interquartile range: 0.32–0.88 mg kgfuel−1). The distribution of the estimated EFs provides insight into the real-world variability of HNCO and HCN emissions, and constrains the wide range of literature EFs obtained from prior dynamometer studies. Our results demonstrate that although biomass burning is a dominant source of both air toxics on a national scale, vehicular emissions play an increasingly important role at a local scale, especially in heavily-trafficked urban areas. The impact of vehicle emissions on urban HNCO levels can be expected to be further enhanced if secondary HNCO formation from vehicle exhaust is considered.
Derivation of gravity wave intrinsic parameters and vertical wavelength using a single scanning OH(3-1) airglow spectrometer
Authors: Wüst Sabine , Offenwanger Thomas , Schmidt Carsten , Bittner Michael , Jacobi Christoph , Stober Gunter , Yee Jeng-Hwa , Mlynczak Martin G. , Russell III James M.
Published: May 2018

Abstract. For the first time, we present an approach to derive zonal, meridional, and
vertical wavelengths as well as periods of gravity waves based on only one
OH* spectrometer, addressing one vibrational-rotational transition.
Knowledge of these parameters is a precondition for the calculation of
further information, such as the wave group velocity vector. OH(3-1) spectrometer measurements allow the analysis of gravity wave
ground-based periods but spatial information cannot necessarily be deduced.
We use a scanning spectrometer and harmonic analysis to derive
horizontal wavelengths at the mesopause altitude above Oberpfaffenhofen
(48.09∘ N, 11.28∘ E), Germany for 22 nights in 2015.
Based on the approximation of the dispersion relation for gravity waves of
low and medium frequencies and additional horizontal wind information, we
calculate vertical wavelengths. The mesopause wind measurements nearest to
Oberpfaffenhofen are conducted at Collm (51.30∘ N,
13.02∘ E), Germany, ca. 380 km northeast of Oberpfaffenhofen, by a
meteor radar. In order to compare our results, vertical temperature profiles of
TIMED-SABER (thermosphere ionosphere mesosphere energetics dynamics,
sounding of the atmosphere using broadband emission radiometry) overpasses
are analysed with respect to the dominating vertical wavelength.
Comparison of total water vapour content in the Arctic derived from GNSS, AIRS, MODIS and SCIAMACHY
Authors: Alraddawi Dunya , Sarkissian Alain , Keckhut Philippe , Bock Olivier , Noël Stefan , Bekki Slimane , Irbah Abdenour , Meftah Mustapha , Claud Chantal
Published: May 2018

Abstract. Atmospheric water vapour plays a key role in the Arctic radiation budget,
hydrological cycle and hence climate, but its measurement with high accuracy
remains an important challenge. Total column water vapour (TCWV) datasets
derived from ground-based GNSS measurements are used to assess the quality of
different existing satellite TCWV datasets, namely from the Moderate
Resolution Imaging Spectroradiometer (MODIS), the Atmospheric Infrared
Sounder (AIRS) and the SCanning Imaging Absorption spectroMeter for
Atmospheric CHartographY (SCIAMACHY). The comparisons between GNSS and
satellite data are carried out for three reference Arctic observation sites
(Sodankylä, Ny-Ålesund and Thule) where long homogeneous GNSS time series of
more than a decade (2001–2014) are available. We select hourly GNSS data that
are coincident with overpasses of the different satellites over the three sites
and then average them into monthly means that are compared with monthly mean
satellite products for different seasons. The agreement between GNSS and
satellite time series is generally within 5 % at all sites for most
conditions. The weakest correlations are found during summer. Among all the
satellite data, AIRS shows the best agreement with GNSS time series, though
AIRS TCWV is often slightly too high in drier atmospheres (i.e. high-latitude
stations during autumn and winter). SCIAMACHY TCWV data are generally drier
than GNSS measurements at all the stations during the summer. This study
suggests that these biases are associated with cloud cover, especially at
Ny-Ålesund and Thule. The dry biases of MODIS and SCIAMACHY observations are
most pronounced at Sodankylä during the snow season (from October to March).
Regarding SCIAMACHY, this bias is possibly linked to the fact that the
SCIAMACHY TCWV retrieval does not take accurately into account the variations
in surface albedo, notably in the presence of snow with a nearby canopy as in
Sodankylä. The MODIS bias at Sodankylä is found to be correlated with cloud
cover fraction and is also expected to be affected by other atmospheric or
surface albedo changes linked for instance to the presence of forests or
anthropogenic emissions. Overall, the results point out that a better
estimation of seasonally dependent surface albedo and a better consideration
of vertically resolved cloud cover are recommended if biases in satellite
measurements are to be reduced in the polar regions.
A novel method for calculating ambient aerosol liquid water content based on measurements of a humidified nephelometer system
Authors: Kuang Ye , Zhao Chun Sheng , Zhao Gang , Tao Jiang Chuan , Xu Wanyun , Ma Nan , Bian Yu Xuan
Published: May 2018

Abstract. Water condensed on ambient aerosol particles plays significant
roles in atmospheric environment, atmospheric chemistry and climate. Before
now, no instruments were available for real-time monitoring of ambient
aerosol liquid water contents (ALWCs). In this paper, a novel method is
proposed to calculate ambient ALWC based on measurements of a
three-wavelength humidified nephelometer system, which measures aerosol light
scattering coefficients and backscattering coefficients at three wavelengths
under dry state and different relative humidity (RH) conditions, providing
measurements of light scattering enhancement factor f(RH). The proposed ALWC calculation method includes two steps: the first
step is the estimation of the dry state total volume concentration of ambient
aerosol particles, Va(dry), with a machine
learning method called random forest model based on measurements of the
“dry” nephelometer. The estimated Va(dry) agrees
well with the measured one. The second step is the estimation of the volume
growth factor Vg(RH) of ambient aerosol
particles due to water uptake, using f(RH) and the
Ångström exponent. The ALWC is calculated from the
estimated Va(dry) and Vg(RH). To validate the new method, the ambient ALWC calculated
from measurements of the humidified nephelometer system during the Gucheng
campaign was compared with ambient ALWC calculated from ISORROPIA
thermodynamic model using aerosol chemistry data. A good agreement was
achieved, with a slope and intercept of 1.14 and −8.6 µm3 cm−3 (r2 = 0.92), respectively. The
advantage of this new method is that the ambient ALWC can be obtained solely
based on measurements of a three-wavelength humidified nephelometer system,
facilitating the real-time monitoring of the ambient ALWC and promoting the
study of aerosol liquid water and its role in atmospheric chemistry,
secondary aerosol formation and climate change.
The Global Ozone Monitoring Experiment: Review of in-flight performance and new reprocessed 1995–2011 level 1 product
Authors: Coldewey-Egbers Melanie , Slijkhuis Sander , Aberle Bernd , Loyola Diego , Dehn Angelika
Published: May 2018

Abstract. The Global Ozone Monitoring Experiment (GOME) on-board the second European Remote Sensing satellite provided measurements of atmospheric constituents such as ozone or other trace gases for the 16 year period from 1995 to 2011. In this paper we present a detailed analysis of the long-term performance of the sensor and introduce the new homogenized and fully calibrated level 1 product which has been generated using the recently developed GOME Data Processor level-0-to-1b (GDP-L1) Version 5.1. By means of the various in-flight calibration parameters we monitor the behavior and stability of the instrument during the entire mission. Severe degradation of the optical components has led to a significant decrease in intensity in particular in channels 1 and 2 covering the spectral ranges of 240–316 nm and 311–405 nm, respectively. Thus, a soft correction based on using the sun as a stable calibration source is applied. Revision and optimization of other calibration algorithms such as the wavelength assignment, polarization correction, or dark current correction resulted in an improved and homogeneous level 1 product that can be regarded as the European satellite reference data for successor atmospheric composition sensors and that provides an excellent prerequisite for further exploitation of GOME measurements.
The Ionospheric response over the UK to major bombing raids during World War II
Authors: Scott Christopher J. , Major Patrick
Published: May 2018

Abstract. The Earth's ionosphere is subject to disturbance from above (via solar variability and space weather effects) and from below (such as tectonic activity, thunderstorms and sudden stratospheric warmings). Identifying the relative contribution of these effects remains challenging, despite recent advances in spacecraft monitoring near-Earth space. Man-made explosions provide a quantifiable proxy for natural terrestrial sources, enabling their impact on ionospheric variability to be studied. In this paper, the contribution of ground-based disturbances to ionospheric variability is investigated by considering the response of the ionospheric F2-layer over Slough, UK, to 152 major bombing raids over Europe during World War II, using a superposed epoch analysis. The median response of the F2 layer is a significant decrease in peak electron concentration (~ 0.3 MHz decrease in foF2). This response is consistent with wave energy heating the thermosphere, enhancing the (temperature dependant) loss rate of O+ ions. The analysis was repeated for a range of thresholds in both time of bombing before the (noon) ionospheric measurement and tonnage of bombs dropped per raid. It was found that significant (~ 2–3σ) deviations from the mean occurred for events occurring between approximately 3 and 7 hours ahead of the noon ionospheric measurements and for raids using a minimum of between 100 and 800 tonnes of high explosives. The most significant ionospheric response (2.99σ) occurred for 21 raids up to 5 hours before the ionospheric measurement, each with a minimum of 300 tonnes of explosives. To ensure that the observed ionospheric response cannot be attributable to space weather sources, the analysis was restricted to those events for which the geomagnetic Ap index was less than 48 (Kp
The role of diatom resting spores in pelagic–benthic coupling in the Southern Ocean
Authors: Rembauville Mathieu , Blain Stéphane , Manno Clara , Tarling Geraint , Thompson Anu , Wolff George , Salter Ian
Published: May 2018

Abstract. Natural iron fertilization downstream of Southern Ocean island plateaus
supports large phytoplankton blooms and promotes carbon export from the mixed
layer. In addition to sequestering atmospheric CO2, the biological
carbon pump also supplies organic matter (OM) to deep-ocean ecosystems.
Although the total flux of OM arriving at the seafloor sets the energy input
to the system, the chemical nature of OM is also of significance. However, a
quantitative framework linking ecological flux vectors to OM composition is
currently lacking. In the present study we report the lipid composition of
export fluxes collected by five moored sediment traps deployed in contrasting
productivity regimes of Southern Ocean island systems (Kerguelen, Crozet and
South Georgia) and compile them with quantitative data on diatom and faecal
pellet fluxes. At the three naturally iron-fertilized sites, the relative
contribution of labile lipids (mono- and polyunsaturated fatty acids,
unsaturated fatty alcohols) is 2–4 times higher than at low productivity
sites. There is a strong attenuation of labile components as a function of
depth, irrespective of productivity. The three island systems also display
regional characteristics in lipid export. An enrichment of zooplankton
dietary sterols, such as C27Δ5, at South Georgia is consistent
with high zooplankton and krill biomass in the region and the importance of
faecal pellets to particulate
organic carbon (POC) flux. There is a strong association of diatom resting
spore fluxes that dominate productive flux regimes with energy-rich
unsaturated fatty acids. At the Kerguelen Plateau we provide a statistical
framework to link seasonal variation in ecological flux vectors and lipid
composition over a complete annual cycle. Our analyses demonstrate that
ecological processes in the upper ocean, e.g. resting spore formation and
grazing, not only impact the magnitude and stoichiometry of the Southern
Ocean biological pump, but also regulate the composition of exported OM and
the nature of pelagic–benthic coupling.
Impacts of climate change and climate extremes on major crops productivity in China at a global warming of 1.5 and 2.0 °C
Authors: Chen Yi , Zhang Zhao , Tao Fulu
Published: May 2018

Abstract. A new temperature goal of “holding the increase in global average
temperature well below 2 ∘C above pre-industrial levels and pursuing
efforts to limit the temperature increase to 1.5 ∘C above
pre-industrial levels” has been established in the Paris Agreement, which
calls for an understanding of climate risk under 1.5 and 2.0 ∘C
warming scenarios. Here, we evaluated the effects of climate change on growth
and productivity of three major crops (i.e. maize, wheat, rice) in China
during 2106–2115 in warming scenarios of 1.5 and 2.0 ∘C using a
method of ensemble simulation with well-validated Model to capture the
Crop–Weather relationship over a Large Area
(MCWLA) family
crop models, their 10 sets of optimal crop model parameters and 70 climate
projections from four global climate models. We presented the spatial
patterns of changes in crop growth duration, crop yield, impacts of heat and
drought stress, as well as crop yield variability and the probability of crop
yield decrease. Results showed that climate change would have major negative
impacts on crop production, particularly for wheat in north China, rice in
south China and maize across the major cultivation areas, due to a decrease
in crop growth duration and an increase in extreme events. By contrast, with
moderate increases in temperature, solar radiation, precipitation and
atmospheric CO2 concentration, agricultural climate resources such as
light and thermal resources could be ameliorated, which would enhance canopy
photosynthesis and consequently biomass accumulations and yields. The
moderate climate change would slightly worsen the maize growth environment
but would result in a much more appropriate growth environment for wheat and
rice. As a result, wheat, rice and maize yields would change by +3.9
(+8.6), +4.1 (+9.4) and +0.2 % (−1.7 %), respectively, in a
warming scenario of 1.5 ∘C (2.0 ∘C). In general, the
warming scenarios would bring more opportunities than risks for crop
development and food security in China. Moreover, although the variability of
crop yield would increase from 1.5 ∘C warming to 2.0 ∘C
warming, the probability of a crop yield decrease would decrease. Our
findings highlight that the 2.0 ∘C warming scenario would be more
suitable for crop production in China, but more attention should be paid to
the expected increase in extreme event impacts.
A global compilation of coccolithophore calcification rates
Authors: Daniels Chris J. , Poulton Alex J. , Balch William M. , Marañón Emilio , Adey Tim , Bowler Bruce C. , Cermeño Pedro , Charalampopoulou Anastasia , Crawford David W. , Drapeau Dave , Feng Yuanyuan , Fernández Ana , Fernández Emilio , Fragoso Glaucia M. , González Natalia , Graziano Lisa M. , Heslop Rachel , Holligan Patrick M. , Hopkins Jason , Huete-Ortega María , Hutchins David A. , Lam Phoebe J. , Lipsen Michael S. , López-Sandoval Daffne C. , Loucaides Socratis , Marchetti Adrian , Mayers Kyle M. J. , Rees Andrew P. , Sobrino Cristina , Tynan Eithne , Tyrrell Toby
Published: May 2018

Abstract. The biological production of calcium carbonate (CaCO3), a process termed calcification, is a key term in the marine carbon cycle. A major planktonic group responsible for such pelagic CaCO3 production (CP) are the coccolithophores, single-celled haptophytes that inhabit the euphotic zone of the ocean. Satellite-based estimates of areal CP are limited to open-ocean waters, with current algorithms utilising the unique optical properties of the cosmopolitan bloom-forming species Emiliania huxleyi, whereas little understanding of the optical properties and environmental responses by species other than E. huxleyi are currently available to parameterise algorithms or models. To aid future areal estimations and validate future modelling efforts we have constructed a database of 2765 CP measurements, the majority of which were measured using 12 to 24 h incorporation of radioactive carbon (14C) into acid-labile inorganic carbon (CaCO3). We present data collated from over 30 studies covering the period from 1991 to 2015, sampling the Atlantic, Pacific, Indian, Arctic and Southern oceans. Globally, CP in surface waters (
Variability of sea salts in ice and firn cores from Fimbul Ice Shelf, Dronning Maud Land, Antarctica
Authors: Vega Carmen Paulina , Isaksson Elisabeth , Schlosser Elisabeth , Divine Dmitry , Martma Tõnu , Mulvaney Robert , Eichler Anja , Schwikowski-Gigar Margit
Published: May 2018

Abstract. Major ions were analysed in firn and ice cores located at Fimbul Ice Shelf (FIS), Dronning Maud Land – DML, Antarctica. FIS is the largest ice shelf in the Haakon VII Sea, with an extent of approximately 36 500 km2. Three shallow firn cores (about 20 m deep) were retrieved in different ice rises, Kupol Ciolkovskogo (KC), Kupol Moskovskij (KM), and Blåskimen Island (BI), while a 100 m long core (S100) was drilled near the FIS edge. These sites are distributed over the entire FIS area so that they provide a variety of elevation (50–400 m a.s.l.) and distance (3–42 km) to the sea. Sea-salt species (mainly Na+ and Cl−) generally dominate the precipitation chemistry in the study region. We associate a significant sixfold increase in median sea-salt concentrations, observed in the S100 core after the 1950s, to an enhanced exposure of the S100 site to primary sea-salt aerosol due to a shorter distance from the S100 site to the ice front, and to enhanced sea-salt aerosol production from blowing salty snow over sea ice, most likely related to the calving of Trolltunga occurred during the 1960s. This increase in sea-salt concentrations is synchronous with a shift in non-sea-salt sulfate (nssSO42−) toward negative values, suggesting a possible contribution of fractionated aerosol to the sea-salt load in the S100 core most likely originating from salty snow found on sea ice. In contrast, there is no evidence of a significant contribution of fractionated sea salt to the ice-rises sites, where the signal would be most likely masked by the large inputs of biogenic sulfate estimated for these sites. In summary, these results suggest that the S100 core contains a sea-salt record dominated by the proximity of the site to the ocean, and processes of sea ice formation in the neighbouring waters. In contrast, the ice-rises firn cores register a larger-scale signal of atmospheric flow conditions and a less efficient transport of sea-salt aerosols to these sites. These findings are a contribution to the understanding of the mechanisms behind sea-salt aerosol production, transport and deposition at coastal Antarctic sites, and the improvement of the current Antarctic sea ice reconstructions based on sea-salt chemical proxies obtained from ice cores.