bluuebunny/crossref_metadata_2025 huggingface dataset:
A reanalysis of one decade of the mass balance series on
Hintereisferner, Ötztal Alps, Austria: a detailed view into annual
geodetic and glaciological observations
Authors: Klug Christoph , Bollmann Erik , Galos Stephan P. , Nicholson Lindsey , Prinz Rainer , Rieg Lorenzo , Sailer Rudolf , Stötter Johann , Kaser Georg
Published: August 2017

Abstract. This study presents a reanalysis of the glaciologically obtained 2001–11 annual glacier mass balances record at Hintereisferner, Ötztal Alps, Austria. The reanalysis is accomplished through a comparison with geodetically derived mass changes, using annual high-resolution airborne laser scanning (ALS). The grid based adjustments for the method-inherent differences are discussed along with associated uncertainties and discrepancies of the two forms of mass balance measurements. A statistical comparison of the two datasets shows no significant difference for seven annual as well as the cumulative mass changes over the ten years record. Yet, the statistical view hides significant differences in the mass balance years 2002/03 (glaciological minus geodetic records = +0.92 m w.e.), 2005/06 (+0.60 m w.e.) and 2006/07 (−0.45 m w.e.). The validity of the results is critically assessed and concludes that exceptional atmospheric circumstances can render the usual glaciological observational network inadequate. Furthermore, we consider that ALS data reliably reproduce the annual mass balance and can be seen as calibration tools of or, under certain circumstances, even as a substitute for the glaciological method.
Sociolinguistic Perceptions of Tú, Usted and Vos in the Highlands of Ecuador
Authors: Toapanta Jesus
Published: August 2017

The Spanish pronouns ‘Tú’, ‘Usted’ and ‘Vos’ all translate into the English second person singular ‘You’. However, this does not mean that they convey the same meaning. In Ecuador, for example, the pronoun Usted is normally used to signal formality, distance, and not familiarity; and, Tú and Vos are often used to signal friendship, closeness, and informality. In addition, these pronouns adopt different meanings depending on where in Ecuador the interaction takes place. For example, in a reciprocal relationship between classmates, Vos implies friendship and closeness in the city of Cuenca, but in the city of Quito Vos implies lack of respect. In this sense, this study examines how college students perceive the usage of these pronouns at home, at the university, and at the workplace. This paper analyses samples taken from three cities in the highlands—Quito, Cuenca, and Loja—and describes how these pronouns are being used at these locations in Ecuador. The results reveal this very peculiar variation and show the different meanings and tendencies of these pronouns.
Clinical judgment in medication administration among nursing students
Authors: Konieczny Leona
Published: August 2017

Nursing education includes the area of pharmacological therapies. Nursing educators may benefit from having students think like a nurse related to medication administration. The increased use of prescription medication and the complexities of medication administration present the need for clinical judgment. Simulation is used as an educational strategy to provide the opportunity for students to practice safe interventions which require the use of judgment to notice changes and interpret and intervene correctly. The comparison of low-fidelity and high-fidelity simulation experience in a study sample (n = 126) is examined for the effect on clinical judgment. The Lasater Clinical Judgment Rubric (LCJR) is used to score students after the simulation related to medication administration. Two of the items in the LCJR, noticing deviations (p = .35) and self analysis (p = .32), are positively affected by the level of fidelity of the simulation. A diverse, nontraditional student study sample demonstrated consistency in LCJR scoring. The outcome of increased clinical judgment may improve safety and nursing care in medication administration among nursing students.
Prevalence of mobility disabilities in nursing home residents and the association with age, BMI, fall risk and social participation
Authors: Fehling Patrick , Dassen Theo
Published: August 2017

Background and aim: Physical mobility is often described as a basic prerequisite for independence, self-determination, and social participation. Older people, particularly those in long-term care facilities, are more often affected by the loss of their mobility. However, the prevalence of the mobility disabilities of nursing home residents and their association with demographic and care-specific/medical factors have so far been studied less. This prevalence study should investigate a possible association of mobility disability with age, BMI, multimorbidity, fall risk, and social participation.Methods: The prevalence study covered the data of residents in 30 German residential care facilities (RCFs). Trained staff nurses used a standardised instrument to collect data about the age, obesity, medical diagnoses, the fall risk, the level of mobility disability, and the need for supporting the social participation of the residents.Results: The representative sample included 2,066 nursing home residents, of whom 81.5% required support in their mobility. The level of a mobility disability or the need for a support in matters of mobility by others was not associated either with age, with the BMI, or with the fall risk of the participants. The groups with higher mobility disability included the more multimorbid participants with more difficult medical diagnoses, and these had a higher need for support in their social participation.Conclusions: It may be that professional care must reflect the premature link between older and obese patients with mobility disability. In addition to nursing diagnoses, medical diagnoses should necessarily be integrated into the nursing assessment. The association between the level of mobility disability and the fall risk, which is often mentioned in the literature, should be critically reflected. Nursing home residents should be informed that there is a possible association between their mobility disability and their social participation.
Three-year assessment of one pre-licensure cohort of baccalaureate nursing students’ attitude, comfort and knowledge of genomics
Authors: Sharoff Leighsa
Published: August 2017

Objective: Descriptive three-year comparison of one pre-licensure cohort of baccalaureate nursing students’ genomic knowledge, attitude and comfort level.Methods: Two analyses were of interest, utilizing the same survey instrument, Genetics/Genomics Literacy Assessment (GGLA): 1) Comparison of pre vs. post intervention on the sophomore (2nd year) class and 2) Retention of the information through junior (3rd year) and senior year (4th year). Two analyses were of interest: 1) Comparison of pre-class vs. post-class assessment on sophomore [2nd year] students and 2) Retention of the information through junior [3rd year] and senior year [4th year].Results: For the total score variable [retention of genomic knowledge over time] data was sophomore vs junior vs senior means of 7.1 vs. 6.9 vs. 8.7, p < .001 showing maintenance from sophomore (post-class assessment) to junior year with an increase in the senior year score for the cohort of students.  Comparison of pre-class vs post-class on the sophomore class resulted in statistically significant differences demonstrating higher knowledge after class.  Enhancement of confidence, perceptions and attitude regarding genomics was evident with comparison of pre-class vs. post-class and overtime after taking foundational course. Overall, data showed that students felt that nurse educators need more confidence in teaching and explaining as well as in patient advocacy.Conclusions: Promoting knowledge and practice integration of universal genomic health requires healthcare professionals, educators and students be knowledgeable and cognizant of their participation to advance client health outcomes.
Teaching professionalism to Saudi nursing students using guided reflection on clinical vignettes
Authors: Ahmad Eman R. , Qahtani Nourah Hasan Al , Nafee Hoda , Al-Eraky Mohamed
Published: August 2017

Background and objective: Professionalism has to be explicitly taught in clinical rotations, yet little is reported about approaches for teaching professionalism in undergraduate nursing education. This study aims to educate undergraduate nursing students on professionalism using guided reflection on clinical vignettes.Methods: Real-life vignettes were designed to describe common professionalism dilemmas in Obstetrics and Gynecological Nursing curriculum. Teachers used a set of seven questions to trigger discussions and guide reflection on each vignette.  During the session, observation notes were taken by peers on teachers’ performance, students interaction and group dynamics during the sessions. After the session, students fill in a survey to report their feedback on the sessions.Results: A total of 91 third-year nursing students participated in the study felt as if they are professional nurses who manage real cases, with feedback from teachers. Students – in groups – were able to indicate stakeholders in each dilemma and advocate their decision. They enjoyed the sessions the highest mean (4.48 ± 0.93) and felt more prepared to encounter similar situations in their future clinical practice.Conclusions: Interactive sessions of guided reflections on professionalism dilemmas enabled students to reflect as individuals and in groups, to respect the scope of practice and acknowledge perspectives of different stakeholders. Apart from students’ feedback, teachers acknowledged essential competencies that have to be addressed while dealing with professionalism dilemmas. A couple of strategies were recommended for teaching professionalism in nursing education using guided reflection. Nursing students need to learn about: emotional intelligence, risk estimation, and strategies for interference in cases of conflict with colleagues, patients and their relatives, doctors in charge, and the fetus, if applicable, in Obstetrics. Guided reflection sessions on clinical dilemmas were found effective to teach professionalism in nursing students in Obstetrics and Gynecological nursing clinical experience.
Democracia e educação na constituição federal, na ldb e no pne: a participação da comunidade na escola
Authors: Silva Nilson Robson Guedes
Published: August 2017

Com o objetivo de ressaltar a importância da participação da comunidade na instituição educacional, enquanto um dos dispositivos que contribui com a democracia na educação, o texto apresenta, em seu início, uma discussão que envolve o significado da educação democrática em diferentes períodos históricos do Brasil, apontando os avanços obtidos a partir do que foi disposto sobre o tema nas normas legais. Nessa discussão, é contextualizada a presença dessa temática na Constituição Federal de 1988, na Lei de Diretrizes e Bases da Educação Nacional de 1996 e no Plano Nacional de Educação de 2014. Após, é debatida a participação da comunidade na gestão escolar, tendo como base referencial uma discussão que envolve diferentes tipos e níveis da participação. Observa-se que a comunidade pode participar da gestão escolar de variadas formas: desde aquelas instituídas pelo Estado (criação de órgãos colegiados, previsão de horário de trabalho coletivo e de planejamentos periódicos, e outros) até às formas instituintes, que são criadas no próprio cotidiano escolar. Na sequência, é colocado em pauta o sentido da participação, ou seja, o que a motiva, buscando-se encerrar provisoriamente o texto com fundamentos que demonstrem a necessidade da comunidade escolar conquistar outros espaços e níveis de participação. Nesse entendimento, a participação pode ter o seu início a partir dos mecanismos instituídos pelo Estado, mas pode ser ampliada com o aprofundamento de seu nível inicial e com a instituição de outras formas de envolvimento da comunidade com a gestão.
21st Century Professional Skill Training Programs for Faculty Members—A Comparative Study between Virginia Tec University, American University & King Saud University
Authors: Al-Majed Asma , Al-Kathiri Fatima , Al-Ajmi Sara , Al-Hamlan Suad
Published: August 2017

The 21st century faculty member is expected to teach, engage the learner, absorb new discoveries and rely on different knowledge in the execution of duties. This calls for up-to-date skills for instruction, assessment, and identification of opportunities by faculty members to promote learning. This paper investigates the prospects of promoting training programs for faculty members in Saudi universities by presenting a comparison of qualitative data between the efforts of two major American universities, the American University and Virginia Tec University, and the efforts of King Saud University. This comparison tries to display how these universities endeavor to meet the current teaching and learning needs. The results are not surprising; the two American universities are coming up with skills training programs that are deemed to be appropriate, including: conferences and workshops, faculty member orientations, consulting, instructional support, online training, discussion forums, family-led discussions, junior faculty training, and summer training programs. They appear to have successfully instituted the 21st century focused skills training programs. Consequently, faculty members from these universities are able to provide students with the knowledge needed to navigate the current challenges. In contrast, King Saud University may have not instituted the programs effectively. Unfortunately, it has not prioritized 21st century professional skill training programs that would make faculty members fit well in the changed learning environments. However, there is a chance for fully implementing new programs that suit the current challenges and needs for faculty members in Saudi universities. Therefore, the paper provides some recommendations for trainers as well as program developers on the light of these results.
Inhibitory action of Vernonia amygdalina extract (VAE) on the corrosion of carbon steel in acidic medium
Authors: Olawale Olamide , Adediran Adesoji Adeolu , Talabi Segun Isaac , Nwokocha Geraldine Chika , Ameh Alewo Opuada
Published: August 2017

This study investigates the inhibition potential of Vernonia amygdalina stem extract (VAE) on the corrosion of mild carbon steel immersed in 1 M HCl solution containing various concentrations of the inhibitor. The corrosion rate and inhibition efficiency were evaluated using mass loss and adsorption techniques. The results revealed that VAE efficiently inhibits the corrosion rate of mild carbon steel immersed in the acidic medium. The concentration of 0.6 g/L provides the highest inhibition efficiency of 78.1 %. The adsorption process was consistent with the physisorption mechanism and obeyed the Langmuir isotherm. The functional groups responsible for inhibition were identified using Fourier Transform Infrared (FTIR) spectra. The surface morphology of the corroded samples examined with Scanning Electron Microscope (SEM) revealed the presence of protective oxide layer. Inhibition efficiency was found depended on the presence of oxalate, phytate, tannins, saponins and flavonoids in the VAE. It has been concluded that VAE is safe, cheap and efficient corrosion inhibitor for mild carbon steel.
A (trans)formação do ethos feminino no discurso publicitário: o caso da marca Volkswagen
Authors: Quincoses Cândice , De Souza Ronivaldo Moreira , Balek Deise
Published: August 2017

O trabalho investiga o ethos feminino no discurso publicitário verificando suas influencias na construção de tendências e comportamentos da sociedade. Tendo em mente que o discurso publicitário se apropria de toda a conjuntura sociopolítica e cultural para construir seus argumentos, esta pesquisa primeiramente toma como base as reflexões de Beauvoir, Bourdieu e Moscovici, para compreensão das distinções de gênero e do papel social da mulher. Em seguida, retoma as noções de ethos e estereótipos da Análise do Discurso da Escola Francesa para verificar como estas noções que habitam o imaginário social se materializam no discurso publicitário. O corpus da pesquisa é composto por três campanhas da Volkswagen – duas durante a ditadura e outra veiculada no Dia Internacional da Mulher em 2010. A análise constatou que mesmo havendo uma mudança do discurso na propaganda mais recente, a figura masculina ainda é colocada como referência e a (trans)formação do ethos feminino acontece através de novas formações discursivas, ideológicas e novos estereótipos atribuídos a ela.
Com tato em tela: afetos e artefatos maquínicos
Authors: Rocha Patricia
Published: August 2017

O presente artigo busca refletir sobre as relações afetivas mediadas pela tecnologia na contemporaneidade. Em um período ditado pela sobreposição de códigos de relacionamentos produzidos durante o processo de mediação tecnológica, o mapa signico para o rastreamento das manifestações ditas de afeto provavelmente advenha da chamada força bruta indicial da emoção presentificada nessas comunicações.
Um outro olhar sobre a comunicação pública: a constituição discursiva de sujeitos políticos no âmbito das organizações
Authors: Marques Ângela , Mafra Rennan , Sá Martino Luis Mauro
Published: August 2017

Este texto evidencia que a abordagem da comunicação pública legitimada na configuração de uma esfera pública movida pela ação comunicativa, e fundamentada em um tipo específico de troca argumentativa reflexiva e recíproca, apresenta fragilidades e pontos polêmicos já identificados nos trabalhos de Habermas, filósofo que desenvolveu a noção. Compreendermos a comunicação pública como processo que não se restringe às negociações entre organizações, instituições, setores públicos e sociedade civil, mas que abrange também tensões, conflitos, embates e dissenso que atravessam as interações que constituem discursivamente sujeitos políticos nos cenários organizacionais. Nesse sentido, mais do que configurar cenários dialógicos voltados ao entendimento mútuo, a comunicação pública se constitui, nos contextos das organizações, como âmbito do dissenso, de conflitos morais que alimentam o gesto de expressão dos falseamentos e das ideologias, das hostilidades e assimetrias, das situações de assédio e de desrespeito.
Canal Futura e os grupos comunitários: uma análise das interações midiatizadas
Authors: Zucolo Rosana Cabral
Published: August 2017

Este artigo discorre sobre a experiência de interação entre o Canal Futura e entidades de ação comunitária que fazem parte de seu campo de articulação e mobilização no social. Analisa as processualidades desencadeadas em torno da implementação do Projeto Maleta Futura: ação que integra as estratégias do canal para a distribuição de seus conteúdos e os de seus parceiros, junto aos grupos sociais de atuação comunitária - no caso, a TV OVO (Oficina de Vídeo Oeste) e o Grupo Ecológico Guardiões da Vida, duas ONGs sediadas nas cidades de Santa Maria e Passo Fundo, no Rio Grande do Sul. O Canal Futura integra as Organizações Globo como um projeto social da Fundação Roberto Marinho, e se caracteriza por uma experimentalidade que permite situá-lo nos espaços de transição da televisão na contemporaneidade. Ao analisar tais processualidades, verifica-se que as diferentes estratégias e operações provocaram afetações de parte a parte, gerando circuitos comunicacionais não previstos e colocando em circulação novos códigos no quadro das interações comunicativas estabelecidas entre os agentes participantes no cotidiano das práticas sociais e midiáticas. Tal análise é parte da pesquisa de doutoramento que examinou a construção de um dispositivo interacional indicativo de uma experiência singular inserida no cenário complexo das dinâmicas relacionais entre mídia e sociedade, e capaz de fornecer elementos para a problematização dos fenômenos comunicacionais decorrentes do processo de midiatização.
Origens do realismo na teoria estética marxista do entreguerras
Authors: Cordeiro Marcos Rogério , Siffert Alysson Quirino
Published: August 2017

Resumo: O objetivo deste artigo é apontar como percursos intelectuais distintos, na primeira metade do século XX, levaram importantes nomes da teoria estética a um método marxista comum, incorporado às discussões literárias no período entreguerras. Nesse sentido, busca-se demonstrar como o período formativo mais idealista do círculo de Bakhtin e dos formalistas russos, bem como o de György Lukács e de Walter Benjamin, não impediram que suas obras culminassem numa noção mais dialética e historicizada sobre o conceito estético de realismo. Assim, buscaremos enfatizar que a ideia de uma condensação não mecânica da realidade na forma artística é a baliza central de todos esses autores, e é o que, em última instância, mais unifica que aparta suas distintas teorias.

 

Palavras-chave: Realismo, Marxismo, Bakhtin, Lukács, Benjamin. 
Realismo e (des)subjetivação: as várias faces da fome em três momentos da literatura brasileira.
Authors: Machado Valéria A S
Published: August 2017

Este texto discute como e por quais vias se processa a construção subjetiva em três romances da literatura brasileira: A fome, de Rodolfo Teófilo; Vidas secas, de Graciliano Ramos e Homens e caranguejos, de Josué de Castro. Usualmente classificados de realistas, os romances, produzidos em épocas e contextos distintos, têm em comum o tratamento da temática da fome. Considerando os textos analisados como construções em que os conceitos de real e realidade são entendidos diferentemente, optou-se por aproximar o conceito de realismo ao de formação discursiva (Cf. Foucault, 1995), esta compreendida como um saber constituído de discursos sobre algo, envolvendo sujeitos que ocupam posições diferentes de acordo com o tempo e o espaço de onde enunciam. O conceito de formação discursiva também se alinha ao de subjetivação na medida em que, como seres de linguagem, os sujeitos constituem a si e as coisas no momento em que falam, construindo sentidos nas e pelas relações que os envolve. Nessa perspectiva, propõe-se entender a realidade e o próprio realismo em suas fronteiras móveis, já que aí estão em jogo discursos, sujeitos, tempos e espaços.
Mapeamento de estudo em psicofísica da música e percepção: processos de aquisição da linguagem visual
Authors: Koga Fabiana Oliveira , Chacon Miguel Claudio Moriel
Published: August 2017

A Psicofísica da música é considerada uma importante área de estudo relacionada à maneira pela qual os seres humanos recepcionam o evento sonoro e o interpretam. Utilizando medidas matemáticas e concepções da Audiometria e Psicofísica, a Psicofísica da música visa mensurar o quanto um indivíduo é capaz de perceber mudanças nos estímulos sonoros, ou simplesmente ser capaz de julgar a qualidade, mudança, localização ou identidade de um som. Diante disso, optou-se por buscar na literatura trabalhos que utilizaram o método psicofísico aplicado a sons musicais. Mais que isso, objetivou-se também, buscar trabalhos que abordassem a percepção, de modo geral, mas com enfoque nas representações musicais internalizadas. Para isso utilizou-se o procedimento metodológico de revisão sistemática da literatura. Os dados foram analisados qualitativamente estabelecendo o uso de frequência na organização deles. Concluiu-se que poucos trabalhos fazem uso da Psicofísica e da percepção em termos de estímulos sonoros. Também, são poucas as áreas do conhecimento dedicadas a esse tipo de estudo. Diante dos dados encontrados, inferiu-se que, caso as áreas como, por exemplo, da Educação Musical ou da Educação fizessem uso dos conceitos psicofísicos e da percepção, muitas estratégias e recursos pedagógicos e didáticos poderiam ser beneficiados.
Análise de um infográfico à luz da Teoria da Mesclagem Conceptual e da Semiótica Plástica greimasiana: a interdisciplinaridade a serviço da compreensão de um texto sincrético
Authors: Dos Santos Aline Nardes
Published: August 2017

Este trabalho tem por objetivo aproximar o aparato teórico da Teoria da Mesclagem Conceptual (FAUCONNIER; TURNER, 2002) às categorias de análise da Semiótica Plástica ou Visual (GREIMAS, 2004), de modo a compreender a construção de significados em um infográfico, cujo tema é a dificuldade de acesso ao aborto legal por mulheres pobres no contexto estadunidense. Por infográfico, entende-se um gênero sincrético que conjunge informações visuais e escritas, organizadas de modo a consolidar uma unidade de comunicação autônoma (CARVALHO; ARAGÃO, 2012). De modo geral, a análise empregada é qualitativa, compreendendo identificação das mesclagens conceptuais emergentes e verificação dos elementos visuais do infográfico que se relacionam a essas mesclagens a partir das categorias topológica, eidética e cromática.  Como os resultados indicam, foi possível enriquecer a descrição das mesclagens conceptuais a partir do emprego das categorias plásticas greimasianas, visto que a própria mesclagem que estrutura o infográfico dá-se por meio da conjunção entre texto e imagem.
Spatial and temporal distribution of manatees (trichechus manatus) reintroduced in the northeastern coast of Brazil
Authors: Lima Régis Pinto de , Alvite Carolina Mattosinho de Carvalho , Reid James P. , Bombassaro Junior Agostinho
Published: August 2017

Many West Indian manatees (Trichechus manatus) that strand along the northeast Brazilian coast are calves, which are often rescued and carried to the Peixe-Boi Project rehabilitation facilities in Itamaracá, Pernambuco State where they are prepared to reintroduction. During the ten years period of October 1994 to December 2004, thirteen captive manatees were radio tagged, released and tracked in three main northeast coastal areas as part of the Brazilian Manatee Reintroduction Program. All individuals were monitored locally with VHF transmitters, during brief periods, four were also tracked remotely with satellite-monitored radio tags. Five manatees (39.5%) had long-term tracks over 14 months or 420 days (Total= 10166 days; Maximum=2663 days; Mean=2031 days; SD=1572 days) that met criteria for inclusion in analyses of spatial and seasonal movement patterns. Manatees were tracked from Praia do Forte, Bahia (12.538ºS/38.474ºW) to Macau, Rio Grande do Norte (5.084ºS/36.682ºW), covering around 1200 km and six states along the northeast coast. Three manatees occupied large home ranges, with each containing a few sites of high fidelity where they spent considerable time, while two used restrict home range having only one site with high fidelity. Others two manatees not showed movements along coast and occupied a restrict area like their fidelity site. Two manatees with short tracking histories showed visible weight loss soon after release and were re-captured after having moved long distances, including offshore movements into deep waters. The high rate of survival for released manatees, their adaptation to areas within the former range of wild manatees, and birth of a calf to a released captive manatee are indicators of the success of the Brazilian Manatee Reintroduction Program.
Mapping the mouse Allelome reveals tissue-specific regulation of allelic expression
Authors: Andergassen Daniel , Dotter Christoph P , Wenzel Daniel , Sigl Verena , Bammer Philipp C , Muckenhuber Markus , Mayer Daniela , Kulinski Tomasz M , Theussl Hans-Christian , Penninger Josef M , Bock Christoph , Barlow Denise P , Pauler Florian M , Hudson Quanah J
Published: August 2017

To determine the dynamics of allelic-specific expression during mouse development, we analyzed RNA-seq data from 23 F1 tissues from different developmental stages, including 19 female tissues allowing X chromosome inactivation (XCI) escapers to also be detected. We demonstrate that allelic expression arising from genetic or epigenetic differences is highly tissue-specific. We find that tissue-specific strain-biased gene expression may be regulated by tissue-specific enhancers or by post-transcriptional differences in stability between the alleles. We also find that escape from X-inactivation is tissue-specific, with leg muscle showing an unexpectedly high rate of XCI escapers. By surveying a range of tissues during development, and performing extensive validation, we are able to provide a high confidence list of mouse imprinted genes including 18 novel genes. This shows that cluster size varies dynamically during development and can be substantially larger than previously thought, with the Igf2r cluster extending over 10 Mb in placenta.
The importance of remembering
Authors: Marder Eve
Published: August 2017

Creativity in science requires the ability to recall information and data, and will suffer if we rely too much on technology to remember things for us.
Planting of neonicotinoid-coated corn raises honey bee mortality and sets back colony development
Authors: Samson-Robert Olivier , Labrie Geneviève , Chagnon Madeleine , Fournier Valérie
Published: August 2017

Worldwide occurrences of honey bee colony losses have raised concerns about bee health and the sustainability of pollination-dependent crops. While multiple causal factors have been identified, seed coating with insecticides of the neonicotinoid family has been the focus of much discussion and research. Nonetheless, few studies have investigated the impacts of these insecticides under field conditions or in commercial beekeeping operations. Given that corn-seed coating constitutes the largest single use of neonicotinoid, our study compared honey bee mortality from commercial apiaries located in two different agricultural settings, i.e. corn-dominated areas and corn-free environments, during the corn planting season. Data was collected in 2012 and 2013 from 26 bee yards. Dead honey bees from five hives in each apiary were counted and collected, and samples were analyzed using a multi-residue LC-MS/MS method. Long-term effects on colony development were simulated based on a honey bee population dynamic model. Mortality survey showed that colonies located in a corn-dominated area had daily mortality counts 3.51 times those of colonies from corn crop-free sites. Chemical analyses revealed that honey bees were exposed to various agricultural pesticides during the corn planting season, but were primarily subjected to neonicotinoid compounds (54% of analysed samples contained clothianidin, and 31% contained both clothianidin and thiamethoxam). Performance development simulations performed on hive populations’ show that increased mortality during the corn planting season sets back colony development and bears contributions to collapse risk but, most of all, reduces the effectiveness and value of colonies for pollination services. Our results also have implications for the numerous large-scale and worldwide-cultivated crops that currently rely on pre-emptive use of neonicotinoid seed treatments.
Assessment of sediment metal contamination in the Mar Menor coastal lagoon (SE Spain): Metal distribution, toxicity, bioaccumulation and benthic community structure
Authors: Marín-Guirao L , Cesar A , Marín A , Vita R
Published: August 2017

The Mar Menor coastal lagoon is one of the largest of the Mediterranean Sea. Ancient mining activities in the mountains near its southern basin have resulted in metal contamination in the sediment. The metal bioavailability of these sediments was determined through laboratory toxicity bioassays using three Mediterranean sea urchin species and two amphipod species, and by means of field bioaccumulation measurements involving the seagrass Cymodocea nodosa. The effect of sediment metal contamination on benthic communities was assessed through benthic infaunal analyses, applying classical descriptive parameters and multivariate techniques. The sediments affected by the mining activities presented high levels of toxicity and metals were also accumulated in the seagrass tissues, pointing to metal bioavailability. Although the classical benthic indices were not clear indicators of disturbance, the multivariate techniques applied provided more consistent conclusions.
Year‐round optical properties and source characterization of Arctic organic carbon aerosols on the North Slope Alaska
Authors: Barrett T. E. , Sheesley R. J.
Published: August 2017

Long‐term data on organic aerosol concentration and optical properties are needed in the Arctic to improve characterization of radiative forcing by atmospheric aerosols. This study presents the seasonal trends (summer 2012 to summer 2013) of organic carbon (OC) and water‐soluble organic carbon (WSOC) along with optical properties of light‐absorbing OC from a yearlong sampling campaign in Utqiaġvik, AK. Ambient OC concentrations for the year range from 0.008 ± 0.002 μg m−3 to 0.95 ± 0.06 μg m−3 with peaks in late summer, early fall, and late winter. On average, WSOC accounted for 57 ± 11% of the total OC burden throughout the sampling campaign, which is consistent with previous WSOC values. In order to understand the potential radiative impacts of light‐absorbing OC, the light absorption properties of WSOC were determined. Seasonal averaging revealed that the highest average mass absorption efficiency value of 1.54 ± 0.75 m2 g−1 was in the fall, with an annual range of 0.70 ± 0.44 to 1.54 ± 0.75 m2 g−1. To quantify the contributions of fossil and contemporary carbon sources to OC, radiocarbon abundance measurements were performed. For OC, fossil contributions were the greatest for select samples in the fall at 61.4 ± 9.8%, with contemporary contributions dominating OC in the spring and summer (68.9 ± 9.8% and 64.8 ± 9.8%, respectively). Back trajectories identified five major source regions to Utqiaġvik throughout the year, with a marine influence from the Arctic Ocean potentially present in all seasons. All these results point to impact from primary and secondary sources of OC in the Arctic.
Examining N cycling in the northern South China Sea from N isotopic signals in nitrate and particulate phases
Authors: Yang Jin‐Yu Terence , Kao Shuh‐Ji , Dai Minhan , Yan Xiuli , Lin Hui‐Ling
Published: August 2017

Nitrogen sources and dynamics, one of the key issues in marine biogeochemical cycles, remain poorly constrained in marginal seas. Here we examine the nitrogen cycle in the northern South China Sea (SCS) by combining data from previous reports with a new data set of N isotopic compositions (δ15N) of nitrate, zooplankton, and sinking particles. Average δ15N in subsurface nitrate is 4.8 ± 0.3‰, similar to that of sinking particles (δ15Nsink of 4.4‰) through the euphotic zone (EZ) collected by floating traps and to documented mean (4.6‰) for long‐term mooring traps at 200 m. This along with oft‐observed shallow nitracline (<100 m) suggests that subsurface nitrate is the primary source of new N to support export production. Moreover, δ15Nsink at the bottom of the EZ resembles those of suspended particles (4.2 ± 1.0‰) and zooplankton (5.4 ± 1.0‰) inside the EZ. High similarity in δ15N among various types of particles including zooplankton in different size fractions in the EZ implies rapid N turnover in the ecosystem. In deep waters at 2000–3000 m, however, additional particulate N fluxes are found due to lateral transport, which contain 15N‐depleted particles, resulting in a downward decreasing trend of δ15Nsink. Incorporation of lighter N by bacteria and selective export of picoplankton are proposed as alternative mechanisms contributing to low δ15Nsink in the deep waters. The significant δ15Nsink change in the deep water column makes the SCS different from most other marginal seas; thus, caution should be made when using sedimentary δ15N to reconstruct paleonitrogen processes.
Geochemical and geophysical constrains on the dynamic topography of the Southern African Plateau
Authors: Jones Alan G. , Afonso Juan Carlos , Fullea Javier
Published: August 2017

The deep mantle African Superswell is considered to contribute to the topographic uplift of the Southern African Plateau, but dynamic support estimates vary wildly depending on the approach and data used. One reason for these large disparities is that the role of lithospheric structure, key in modulating deep dynamic contributions to elevation, is commonly ignored or oversimplified in convection studies. We use multiple high‐quality geophysical data coupled with xenolith‐based geochemical constraints to compute the isostatic lithospheric contribution to the elevation of the Plateau, facilitating isolation of the current dynamic component from the total observed elevation. We employ a multiobservable stochastic algorithm to invert geoid anomaly, surface‐wave dispersion data, magnetotelluric data, and surface heat flow to predict elevation in a fully thermodynamically and internally‐consistent manner. We find that a compositionally layered 230 ± 7 km thick lithosphere is required to simultaneously fit all four data types, in agreement with abundant independent xenolith evidence. Our stochastic modeling indicates a lithospheric contribution to elevation of the order of 670 m, which implies dynamic support arising from the convecting sublithospheric mantle of ∼650 m. Our results have important implications for the understanding of lithospheric‐deep mantle feedback mechanisms and for calibrating dynamic topography estimates from global convection studies.
Electronic environments of ferrous iron in rhyolitic and basaltic glasses at high pressure
Authors: Solomatova Natalia V. , Jackson Jennifer M. , Sturhahn Wolfgang , Rossman George R. , Roskosz Mathieu
Published: August 2017

The physical properties of silicate melts within Earth's mantle affect the chemical and thermal evolution of its interior. Chemistry and coordination environments affect such properties. We have measured the hyperfine parameters of iron‐bearing rhyolitic and basaltic glasses up to ~120 GPa and ~100 GPa, respectively, in a neon pressure medium using time domain synchrotron Mössbauer spectroscopy. The spectra for rhyolitic and basaltic glasses are well explained by three high‐spin Fe2+‐like sites with distinct quadrupole splittings. Absence of detectable ferric iron was confirmed with optical absorption spectroscopy. The sites with relatively high and intermediate quadrupole splittings are likely a result of fivefold and sixfold coordination environments of ferrous iron that transition to higher coordination with increasing pressure. The ferrous site with a relatively low quadrupole splitting and isomer shift at low pressures may be related to a fourfold or a second fivefold ferrous iron site, which transitions to higher coordination in basaltic glass, but likely remains in low coordination in rhyolitic glass. These results indicate that iron experiences changes in its coordination environment with increasing pressure without undergoing a high‐spin to low‐spin transition. We compare our results to the hyperfine parameters of silicate glasses of different compositions. With the assumption that coordination environments in silicate glasses may serve as a good indicator for those in a melt, this study suggests that ferrous iron in chemically complex silicate melts likely exists in a high‐spin state throughout most of Earth's mantle.
Gravity wave spectra in the lower stratosphere diagnosed from project loon balloon trajectories
Authors: Schoeberl M. R. , Jensen E. , Podglajen A. , Coy L. , Lodha C. , Candido S. , Carver R.
Published: August 2017

Project Loon has been launching superpressure balloons since January 2013 to provide worldwide Internet coverage. These balloons typically fly between 18 and 21 km and provide measurements of winds and pressure fluctuations in the lower stratosphere. We divide 1560 Loon flights into 3405 two‐day segments for gravity wave analysis. We derive the kinetic energy spectrum from the horizontal balloon motion and estimate the temperature perturbation spectrum (proportional to the potential energy spectrum) from the pressure variations. We fit the temperature (and kinetic energy) data to the functional form T′2 = T′o2[ω/ωο)α, where ω is the wave frequency, ωο is daily frequency, T′o is the base temperature amplitude, and α is the spectral slope. Both the kinetic energy and temperature spectra show −1.9 ± 0.2 power‐law dependence in the intrinsic frequency window 3–50 cycles/day. The temperature spectrum slope is weakly anticorrelated with the base temperature amplitude. We also find that the wave base temperature distribution is highly skewed. The tropical modal temperature is 0.77 K. The highest amplitude waves occur over the mountainous regions, the tropics, and the high southern latitudes. Temperature amplitudes show little height variation over our 18–21 km domain. Our results are consistent with other limited superpressure balloon analyses. The modal temperature is higher than the temperature currently used in high‐frequency gravity wave parameterizations.
Effects of chemical composition and mixing state on size‐resolved hygroscopicity and cloud condensation nuclei activity of submicron aerosols at a suburban site in northern Japan in summer
Authors: Müller Astrid , Miyazaki Yuzo , Aggarwal Shankar G. , Kitamori Yasuyuki , Boreddy Suresh K. R. , Kawamura Kimitaka
Published: August 2017

Ambient hygroscopic properties, numbers of size‐segregated cloud condensation nuclei (CCN) at different supersaturations (0.1%–0.8%), and the chemical composition of submicron particles were simultaneously measured at a suburban site in northern Japan in summer. Two distinct periods with different growth factors (GF), CCN activation diameters, and chemical compositions were observed. The data suggest that internally mixed sulfate aerosols dominated the accumulation size mode in relatively aged aerosols during the first period, whereas particles observed during the latter periods showed external mixing dominated by organics, which was linked to low hygroscopicity and CCN activity. In particular, the higher loading of water‐soluble organic matter (WSOM; ~60% of OM by mass) with increased WSOM/sulfate ratios corresponded to a low hygroscopicity parameter derived from the CCN measurement (κCCN = 0.15 ± 0.02) at a dry diameter (Ddry) of 146 nm. The results suggest that WSOM, likely dominated by the influence of biogenic sources, contributed to reducing the hygroscopicity and CCN activation at this particle size. Temporal variations in the number concentrations for low GF mode at Ddry = 49.6 nm were similar to those in the elemental carbon (EC) concentration, suggesting that EC contributed to reducing hygroscopicity at this smaller size. Our results suggest that chemical composition and mixing state are important factors controlling the hygroscopicity and CCN activation of submicron particles. These results provide useful data sets of size‐resolved subsaturated and supersaturated hygroscopicity and highlight the importance of the abundance of OM relative to sulfate in predicting the effects on climate change.
Optical power and energy radiated by return strokes in rocket‐triggered lightning
Authors: Quick Mason G. , Krider E. Philip
Published: August 2017

The broadband optical radiation covering the visible and near‐infrared (VNIR) spectral regions (0.4–1.0 μm) has been measured from 70 negative return strokes (RS) in rocket‐triggered lightning; 17 events were recorded in 2011, and 53 were recorded in 2012. The radiometers were calibrated, and all measurements were time‐correlated with currents measured at the channel base. The risetime and peak of an irradiance waveform are determined primarily by the RS current and by the geometrical growth and total length of channel that is in the field of view of the sensor. Following an initial peak, the irradiance decays faster than the current until there is a plateau or secondary maximum 20 to 40 μs (median of 22 μs) after the peak current, a time when the current itself is steadily decreasing. Estimates of the space‐ and time‐average optical power per unit length (ℓo) that is emitted at the source during onset of RS have been computed using the measured slopes of 70 irradiance waveforms together with an assumption that the initial speed of propagation is 1.2 × 108 m/s. The values range from 0.25 to 9.5 MW/m, with a mean and standard deviation of 2.4 ± 1.7 MW/m, and they are in good agreement with prior estimates of ℓo that were made by Quick and Krider (2013) for the subsequent return strokes in natural lightning that reilluminate a preexisting channel. The values of ℓo also agree with numerical estimates of the VNIR power per unit length that were computed by Paxton et al. (1986). Estimates of the peak optical power per unit length (ℓR) that is radiated at the source have been derived from the peaks of 53 irradiance waveforms, and the values range from 0.4 to 11 MW/m with a mean and standard deviation of 4.2 ± 2.5 MW/m. Both ℓo and ℓR are approximately proportional to the square of the peak current at the channel base. Estimates of the total optical energy per unit length, Jo, that is radiated in the VNIR have been computed by integrating the irradiance waveforms over 2 ms. The values of Jo have a mean and standard deviation of 150 ± 140 J/m, and they are proportional to the total charge that is transported to ground in that interval.
Field‐Effect Transistors Using Thin Flakes of Misfit Layer Compound (LaS)1.20CrS2
Authors: Shimazu Yoshihiro , Takanashi Masaya , Kurihara Daiki , Fujisawa Yutaro , Arai Kensuke , Iwabuchi Tatsuya , Suzuki Kazuya
Published: August 2017

Misfit layer compounds consist of two sublattices that are incommensurately modulated. These sublattices have the structures of cubic monochalcogenide and transition‐metal dichalcogenide monolayers. In this work, a semiconducting misfit layer compound (LaS)1.20CrS2 is synthesized by chemical vapor transport. In absence of intervening LaS layers, a CrS2 layer does not exist in a stable state. Using thin flakes of (LaS)1.20CrS2 obtained by mechanical exfoliation, field‐effect transistors are fabricated. The devices show n‐type transport characteristics. An on/off ratio of ≈250 (at 120 K) and mobility of 0.3 cm2 V−1 s−1 (at room temperature) are observed. Temperature dependence of the conductance obeys thermal activation with the activation energy nearly linearly dependent on the gate voltage. This gate‐voltage dependence suggests that the density of trap states is considerably larger than that of MoS2 thin flakes.
Silver‐Catalyzed [3+2] Cycloaddition of Azomethine Ylides with Isocyanides for Imidazole Synthesis
Authors: Hu Zhongyan , Dong Jinhuan , Xu Xianxiu
Published: August 2017

A silver‐catalyzed aerobic oxidative [3+2] cycloaddition of azomethine ylides with aryl or heteroaryl isocyanides has been developed. The reaction represents a novel protocol for the efficient and practical synthesis of 1,2‐diarylimidazoles bearing a broad range of substituents in good to excellent yields under mild conditions. The practicability of this cycloaddition was shown by a gram‐scale synthesis and a double cycloaddition for the construction of highly conjugated polyarylimidazole systems.

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Single Crystalline Metal Films as Substrates for Graphene Growth
Authors: Zeller Patrick , Weinl Michael , Speck Florian , Ostler Markus , Henß Ann‐Kathrin , Seyller Thomas , Schreck Matthias , Wintterlin Joost
Published: August 2017

Single crystalline metal films deposited on YSZ‐buffered Si(111) wafers were investigated with respect to their suitability as substrates for epitaxial graphene. Graphene was grown by CVD of ethylene on Ru(0001), Ir(111), and Ni(111) films in UHV. For analysis a variety of surface science methods were used. By an initial annealing step the surface quality of the films was strongly improved. The temperature treatments of the metal films caused a pattern of slip lines, formed by thermal stress in the films, which, however, did not affect the graphene quality and even prevented wrinkle formation. Graphene was successfully grown on all three types of metal films in a quality comparable to graphene grown on bulk single crystals of the same metals. In the case of the Ni(111) films the originally obtained domain structure of rotational graphene phases could be transformed into a single domain by annealing. This healing process is based on the control of the equilibrium between graphene and dissolved carbon in the film. For the system graphene/Ni(111) the metal, after graphene growth, could be removed from underneath the epitaxial graphene layer by a pure gas phase reaction, using the reaction of CO with Ni to give gaseous Ni(CO)4.