bluuebunny/crossref_metadata_2025 huggingface dataset:
A competência oral em inglês do trabalhador como estratégia de endomarketing: um estudo de caso em midscale hotéis em Florianópolis/SC
Authors: Silva Marimar da , Ramos Luciana de Jesus
Published: April 2021

A indústria hoteleira é um setor voltado à prestação de serviços desenvolvidos por pessoas mediados pela linguagem. Assim entendida, a competência comunicativa de seus trabalhadores passa a ser um elemento imprescindível para assegurar a competitividade dessa indústria. No entanto, pesquisas sobre essa temática no Brasil vêm indicando fragilidades em idiomas. Nesse sentido, este estudo, de natureza qualitativo-interpretativa, busca diagnosticar a competência oral em inglês do trabalhador do setor de recepção de midscale hotéis em Florianópolis/SC. Para a geração dos dados, foram aplicados questionários em português e entrevistas em inglês com os participantes. A análise dos dados revelou que o nível de competência oral em inglês declarado pelos participantes no questionário difere do identificado na entrevista, sugerindo necessidade de investimento no idioma, visando equilibrar as estratégias de marketing externo e interno no contexto estudado. Sugere-se que seja ampliado o escopo do presente estudo para corroborar ou refutar os resultados aqui relatados.
Mapeamento dos estudos sobre políticas linguísticas e internacionalização no Brasil: uma selfie
Authors: Guimarães Renata Mourão , Pereira Lauro Sérgio Machado
Published: April 2021

Este estudo mapeou e discutiu trabalhos que tratam da internacionalização da educação na sua interface com políticas linguísticas, de Programas de Pós-Graduação em Letras e Linguística no Brasil, entre 2009 a 2019. Trata-se de pesquisa bibliográfica, no Catálogo de Teses e Dissertações da Capes (BTD) e na Biblioteca Digital Brasileira de Teses e Dissertações (BDTD). A partir das teses e dissertações investigadas, é possível perceber: a) interesse crescente da área por essas temáticas, afirmando o caráter inter/transdisciplinar dos estudos de linguagem e a relevância das línguas na internacionalização; b) predomínio de pesquisas no eixo Sul-Sudeste; c) foco em programas de governo; d) estudos em contexto de ensino de inglês e francês. Assim, apontamos necessidade de estudos em contexto de outras línguas e enfoques, e de pesquisas que discutam alternativas para estratégias tradicionais de internacionalização e para o rompimento de práticas hegemônicas e excludentes de linguagem.
Um panorama da internacionalização da educação superior na área do ensino de línguas adicionais e da pesquisa no Brasil
Authors: Silva Kleber Aparecido da , Xavier Rosely Perez
Published: April 2021

Nos dias atuais, quando as práticas sociais são dinâmicas e fluidas, a comunicação acontece de maneira complexa por intermédio das línguas e de uma diversidade de recursos semióticos e multimodais. Em face disso, a internacionalização para o ensino e para a pesquisa nas áreas de línguas se destaca moldando as trocas interacionais e interculturais. Neste contexto, o presente artigo, de (re)leitura crítica de literatura, aborda o conceito de internacionalização do/no ensino superior e o relaciona com o ensino e a pesquisa  na área de línguas. O objetivo é evidenciar o panorama das ações de internacionalização no contexto brasileiro como preâmbulo necessário para apresentar os vários artigos que compõem este dossiê.
"É preciso ver?": práticas de ensino inclusivas na Educação Física escolar
Authors: Rafael Leandro Soares Assunção , Fernandes Gyna de Ávila
Published: April 2021

O presente trabalho se caracteriza como um relato de experiência proveniente da imersão docente de Residentes do Programa Residência Pedagógica (RP) -UFMG. Tem como objetivo apresentar a organização de um projeto de ensino, nomeado “É preciso ver?”, e suas estratégias de inclusão para uma turma de 9º ano de Ensino Fundamental de uma escola pública da rede municipal da Prefeitura de Belo Horizonte. Inicialmente se apresenta o contexto em que se deu a elaboração do projeto. Depois, o percurso metodológico e de planejamento do projeto de ensino. Por fim, se reflete e relata três ações inclusivas, a saber: a) estratégia diagnóstica; b) estratégia de ensino; e c) estratégia avaliativa. Essas, lançam luzes às possibilidades de práticas inclusivas na Educação Física escolar construída por meio de uma demanda de ensino proposta aos Residentes no fim do programa.
Elementos gímnicos presentes nas brincadeiras no parque de uma instituição escolar infantil: uma abordagem com foco nos padrões básicos de movimento
Authors: Nobre Juliana Nogueira Pontes , Silva Ana Flávia da , Lopes Priscila , Niquini Cláudia Mara
Published: April 2021

A pesquisa teve como objetivo identificar a presença de elementos gímnicos nas brincadeiras de crianças em um parque construído com material alternativo (pneus) no contexto de uma instituição educativa de Educação Infantil no Município de Diamantina-MG, amparado no referencial dos Padrões Básicos de Movimento (PBMs) elencados por Russel (2010). Com caráter descritivo, utilizou-se como técnica de coleta das informações a observação sistemática, realizadas durante horários destinados ao livre brincar, com presença do professor regente. Neste sentido, a pesquisa contou com fotos, filmagens e anotações realizadas em diário de campo, possibilitando interpretar e categorizar os movimentos infantis na abordagem dos PBMs. Os resultados apontam que estes padrões permeiam o universo infantil através das brincadeiras e experimentações corporais, nas quais precisam ser estimuladas e vivenciadas pelas crianças no sentido de se proporcionar a ampliação dos saberes corporais.
CITOCINAS E MORBIDADE CARDÍACA NA DOENÇA DE CHAGAS
Authors: Bigolin Laura De Lima , De Moura Gabriela Vasconcelos , Contini Vítor Pereira , Leusin Vandré Bernardo , Wrague Kéven Martins
Published: April 2021

INTRODUÇÃO: A Organização Mundial de Saúde (OMS) estima que cerca de 8 milhões de pessoas no mundo apresentam a doença de chagas, sendo que dessas cerca de 20 a 40% desenvolvem algum dano cardíaco. A cardiomiopatia chagásica crônica (CCC) é uma cardiomiopatia inflamatória dilatada que apresenta um prognóstico negativo devido a elevada expressão de citocinas inflamatórias. A morbimortalidade na doença de chagas segue elevada devido a negligência, pois 20% dos infectados não têm acesso ao diagnóstico e tratamento da doença devido a estigmas e sintomatologia silenciosa, o que facilita o surgimento das sequelas. OBJETIVO: Analisar prevalência de citocinas plasmáticas e sua influência na morbimortalidade de pacientes com cardiomiopatia chagásica comparada a grupo controle indeterminado MÉTODOS: Foram coletadas informações no banco de dados PubMed e LILCAS, incluindo artigos originais em inglês e português, indexados pelos descritores DECs/MeSH: “Cardiomiopatia”, “Chagas”, “Citocinas”. Ao total, foram considerados 7 artigos, após aplicar o critério de exclusão de estudos clínicos com pequena amostra e publicados há mais de 15 anos, apenas 3 foram selecionados para essa revisão bibliográfica. RESULTADOS: Obteve-se após comparação de dados de exames plasmáticos que pacientes do grupo indeterminado apresentaram maior expressão de interleucina 10 (IL-10) comparada aos pacientes com CCC, associada com melhor funcionalidade cardíaca após avaliação da fração de ejeção e valores de diâmetro diastólico do ventrículo esquerdo. Já os pacientes com CCC tiveram expressão mais elevada de interferon gama (IFN-γ) e fator de necrose tumoral alfa (TNF-α), além de prevalência de linfócitos T Th1 no infiltrado inflamatório, que evidencia o dano tecidual e intensa fibrose, gerando alteração no ritmo cardíaco, insuficiência cardíaca congestiva e eventos tromboembólicos. CONCLUSÃO: As citocinas inflamatórias tem influência direta na gênese do infiltrado inflamatório e dano tecidual miocárdico na doença chagásica crônica gerando alterações na dilatação ventricular e uma série de desfechos de alta mortalidade quando comparado a demais de etiologia não inflamatória. Isso se caracteriza como um problema de negligência de políticas públicas de saúde, pois existe forma de prevenção da doença e tratamentos que evitem sua cronicidade.
ANGIOEDEMA HEREDITÁRIO: PRÁTICAS IATROGÊNICAS
Authors: De Souza Júlia Diniz , Da Nóbrega Citânia Cordeiro , De Oliveira Nefertite Augusta Guimarães , Mandu Samara Rayssa Da Silva
Published: April 2021

INTRODUÇÃO: O angioedema hereditário (AEH) é uma doença autossômica dominante, caracterizada por episódios frequentes de edema subcutâneo e/ou submucoso. No Brasil, embora a prevalência do AEH seja baixa, quando não diagnosticada corretamente a mortalidade pode ser superior a 30%. A patologia atualmente ainda é de pouco conhecimento médico, por vezes, o diagnóstico é tardio, provocando práticas iatrogênicas que podem resultar no óbito. OBJETIVOS: Analisar as publicações científicas sobre as intervenções iatrogênicas causadas no AEH. MATERIAL E MÉTODOS: Foi elaborada uma revisão bibliográfica, no mês de março de 2021. Para a obtenção dos artigos científicos, foram realizadas pesquisas sobre o tema, na Biblioteca Virtual em Saúde (BVS) e base de dados LILACS e MEDLINE, os artigos encontrados estão no período compreendido entre 2016 à 2021. Foram utilizados os descritores, “angioedema hereditário”, “erro médico” e “iatrogenia”. RESULTADOS: De acordo com os estudos, foi possível analisar que os erros no AEH são frequentes, causados principalmente pela falta de conhecimento acerca da patologia, mas também devido a possível confusão no diagnóstico, visto que a clínica da doença é similar a reações alérgicas, intoxicações e abdome agudo. Segundo os autores, as iatrogenias mais comuns causadas no AEH são, a laparotomia exploratória, que pode causar complicações cirúrgicas nos pacientes, a apendicectomia, e também as grandes investigações laboratoriais, estas podem acabar atrasando o diagnóstico verdadeiro, no caso de um edema de glote, quando não diagnosticado e tratado previamente o paciente pode evoluir ao óbito. As intervenções iatrogênicas poderiam ter sido evitadas com diagnóstico correto e precoce, através da história, quadro clínico e dosagem dos níveis séricos de C4, C1-INH funcional e quantitativo. CONCLUSÃO: O presente estudo analisou que as práticas iatrogênicas são recorrentes no angioedema hereditário, principalmente, porque a falta de conhecimento acerca da doença causa confusão na hora do diagnóstico e pode levar o paciente ao óbito. A compreensão acerca do assunto pode mudar cenários e por isso é necessário que tenham mais estudos sobre o tema, para que os profissionais conheçam a doença e assim evitem as intervenções iatrogênicas.
ASPECTOS IMUNOLÓGICOS DA ALERGIA À PROTEÍNA DO LEITE DE VACA MEDIADA POR IGE
Authors: Silva Nicoly Ferreira , Filha Adriano Antônio Dos Anjos Lima , Andrade Ana Carolina Medeiros , De Souza Júlia Diniz , De Sá Maria Do Socorro Viana Silva
Published: April 2021

Introdução: A alergia à proteína do leite de vaca (APLV) é uma hipersensibilidade alimentar documentada, majoritariamente, como tipo I (IgE mediada) pela classificação de Gell e Coombs que aborda reações mediadas pelo sistema imune inato e pelo adaptativo. No Brasil, estudos demonstram que crianças com sintomas gastroenterológicos e suspeita de APLV têm prevalência de 5,4% e incidência de 2,2%, sendo essa a alergia alimentar mais comum abaixo de quatro anos de idade. Objetivo: Analisar publicações que abordam os aspectos imunológicos da hipersensibilidade ao leite de vaca mediada por IgE. Material e metodologia: Trata-se de uma revisão bibliográfica, realizada em março de 2021. Para a obtenção dos artigos científicos foi feito um cruzamento de informações advindas das bases de dados Pubmed, Uptodate, LILACS e MEDLINE. Adotou-se os seguintes critérios inclusivos: artigos de revisão sistemática e que foram publicados nos últimos 5 anos (2016-2021). Resultados: As reações alérgicas agudas comumente são respostas imunológicas IgE mediadas - relacionadas a um ou mais alérgenos presentes na composição proteica do leite bovino - sendo mais toleradas a partir dos três anos de idade. Entre os alérgenos, têm-se subtipos da caseína (alfa, beta e kappa), que compõe cerca de 80% do material proteico, e do soro do leite destacando os subtipos BLG (beta-lactoglobulina) e ALA (alfa-lactalbumina). Essas reações variam de sintomas leves a anafilaxia e acontecem até duas horas após exposição ao alérgeno a partir do lançamento de mediadores inflamatórios nos tecidos celulares - sendo a pele o local mais comumente acometido, além de recorrentes manifestações gastrointestinais. Conclusão: Uma vez que não há um único teste ou uma exata combinação de exames capazes de diagnosticar o quadro de APLV, apesar do destaque atribuído ao Teste de Provocação Oral (TPO), é necessária uma avaliação individualizada do paciente com sintomas para essa condição clínica. Deve-se realizar um planejamento nutricional que substitua os lacticínios e apenas reinseri-los na dieta em um momento oportuno, levando em consideração que essa condição tende a ser mais tolerada na idade escolar. Além disso, é essencial a orientação para o uso de epinefrina auto injetável, de modo a evitar reações anafiláticas graves.
Las maras salvadoreñas
Authors: Martel Trigueros Roxana
Published: April 2021

Este ensayo reflexiona en este nuevo rostro generador de miedo, entre la ciudadanía salvadoreña, el cual es producto de una presencia sistemática en el discurso político institucional, difundido a través de los medios de comunicación masiva, que, además, se ha transnacionalizado. Las maras se han convertido en tema de debates académicos, pero sobre todo en la “anomalía” que los gobiernos de la región centroamericana, de México y de Estados Unidos pretenden penalizar o, en términos de Foucault, disciplinar. Pero para comprender mejor la complejidad de este fenómeno, este ensayo busca vincular la realidad de las pandillas con los acontecimientos históricos del país, porque, de esta manera, los procesos para construir una cultura autoritaria, anclada en el miedo, se presentan de forma hilvanada. El fenómeno no es nuevo como objeto de estudio, pero es urgente discutir nuevas formas para abordarlo. Las pandillas, denominadas maras, no son expresión de una violencia ahistórica ni son extrañas al tipo de sociedad. Son jóvenes y adultos, mujeres y hombres, niños y niñas, con rostros que, aun cuando se intente negar, pertenecen a esos espacios denominados “nación”.

ECA Estudios Centroamericanos, Vol. 61, No. 696, 2006: 957-979.
Analysis of motivational factors, possible deterrents and actualities about blood donation in Zimbabwe
Authors: Vincent Kampira , Maxwell Mashasha , Esther Chigidi
Published: April 2021

Background: Blood is a body fluid responsible for transportation of nutrients, oxygen and metabolic waste. It is a non-pharmaceutical product obtained through voluntary donations. Blood transfusion is very important in the health system of any nation. Patients who are in need of blood donation expect the availability of adequate blood to satisfy their demands. Nevertheless, this is not so, mainly in third world countries like Zimbabwe where less than 6 people donate blood per 1000 populace. We need to deeply understand motivators, possible deterrents and available blood donor knowledge in order to have adequate regular voluntary non-remunerated blood donors.

Methods: A cross sectional study of donors incorporating purposive sampling technique was used and a sample size of 465 was used. A self-administered questionnaire was used where donors were rating importance of: factors that motivate or deter their interest to donate blood and rate their blood donation knowledge. Statistical methods were used for reliability and correlation tests.

Results: Most of the 465 participants were 1st time donors262(56.3%) and 203(43.7%) had some donation history. All donors endorsed that there exist factors that motivate them to donate blood which included the desire to help someone in need 386 (83%), good attitude of staff 419 (90%), reminders to donate381 (82%) and donor incentives 409 (88%) with their corresponding response rate. Six out of the nine suggested deterrents were endorsed as significant deterrents to blood donation. The corresponding support rate for each deterrent are absence of incentives 529(82%), poor attitude of staff 363(78%), myths and beliefs, 330(71%), feeling bad after donation, 251(54%) and the belief that blood will be sold 330(71%). Most people did not know the minimum age to donate blood as only 54 (11.61%) and only 168(36.13%) knew the correct interval between donations which should be 4 months. Only 171(36.77%) knew that blood expire.

Conclusion: Our findings suggest that more donor drives needs to be taken educating people on blood donation, motivating donors to donate whenever there is blood shortage. Young donors are more attracted to concrete items as incentives and females donate more than males. Attitude of staff can motivate or demotivate donors to continue with this altruism gesture.
Translation based on cultural aspect: a study regarding how translating text different traditional in two countries
Authors: Filladsen Jorden
Published: April 2021

The gap between language and culture in turn leaves a problem of untranslatability. There will be linguistic and cultural aspects that are not distracted by BT. In order to intelligently translate cultural nuances, translators must have knowledge of BS and BT culture. For example, states that proverbs in Malay language poetry may portray universal thinking. However, these proverbs are often packaged in a unique metaphorical depiction of language in Malay. Translated text that does not meet the explicit aspect can be ascertained that it is difficult to understand or cannot be understood at all. The aspect of intelligence relates to how easy/difficult it is for readers to understand the information contained in target language. In other words, the sharpness aspect correlates with the readability of a translated text.
Translation affects literary and cultural systems: how to observe the features of translation?
Authors: Plyth Parl S.
Published: April 2021

In the field of translation studies, it has been researched how good translation should be done, how translation affects other literary and cultural systems, how translation is carried out to produce the desired response, who influences translation, how translation can be said to be a tool for mastering marginalized groups, and Finally, how to observe the translation features of the translated text database. The flow of this development leads to a conclusion that research in the early days started from the essence of translation and shifted and branched to things that were not closely related to the essence of translation, e.g. postcolonial studies in the field of translation. However, some try to come back with a new tool (corpus study). From the point of view of the language industry, there is an irresistible trend. The first trend is that the industry now views translation as a means to achieve communication goals (business, politics, culture, etc.). The second trend is better computer technology and the increasingly widespread use of cloud computing. As a result, this development, supported by economic globalization, has forced many changes in professions related to the language industry.
Identification and validation of key miRNAs and miRNA–mRNA regulatory network associated with uterine involution in postpartum Kazakh sheep
Authors: Yang Heng , Fu Lin , Luo Qifeng , Li Licai , Zheng Fangling , Wen Jiayu , Li Chenjing , Luo Xingxiu , Zhao Zongsheng , Xu Huihao
Published: April 2021

Abstract. MicroRNAs (miRNAs) are widely expressed in different mammalian tissues and
exert their biological effects through corresponding target genes. miRNA
target genes can be rapidly and efficiently identified and screened by
combining bioinformatics prediction and experimental validation. To
investigate the possible molecular regulatory mechanisms involving miRNAs
during uterine involution in postpartum ewes, we used Illumina HiSeq
sequencing technology to screen for the number and characteristics of miRNAs
in faster uterine involution and normal uterine involution group. A total of
118 differentially expressed miRNAs, including 33 known miRNAs and 85 new
miRNAs, were identified in the hypothalamic library, whereas 54 miRNAs,
including 5 known miRNAs and 49 new miRNAs, were identified in the uterine
library. Screening with four types of gene prediction software revealed 73
target genes associated with uterine involution, and subsequently, GO
annotation and KEGG pathway analysis were performed. The results showed
that, in the hypothalamic–uterine axis, uterine involution in postpartum
ewes might primarily involve two miRNA-target gene pairs, namely,
miRNA-200a–PTEN and miRNA-133–FGFR1, which can participate in GnRH signal
transduction in the upstream hypothalamus and in the remodeling process at
the downstream uterus, through the PI3K–AKT signaling pathway to influence
the recovery of the morphology and functions of the uterus during the
postpartum period in sheep. Therefore, identification of differentially
expressed miRNAs in this study fills a gap in the research related to miRNAs
in uterine involution in postpartum ewes and provides an important reference
point for a comprehensive understanding of the molecular mechanisms
underlying the regulation of postpartum uterine involution in female
livestock.
Impacts of tropical cyclones on the thermodynamic conditions in the tropical tropopause layer observed by A-train satellites
Authors: Feng Jing , Huang Yi
Published: April 2021

Abstract. The tropical tropopause layer (TTL) is the transition layer between the troposphere and the stratosphere. Tropical cyclones may impact the TTL by perturbing the vertical distributions of cloud, temperature, and water vapor, although this impact is poorly quantified due to the lack of collocated data. To address this problem, we implement a synergistic retrieval approach to obtain the thermodynamic profiles and ice water content above thick high-level clouds using the A-Train satellite measurements that pass over the tropical cyclones. This study detects the signature of cyclone impact on the distribution patterns of cloud, water vapor, temperature, and radiation by compositing these thermodynamic fields with respect to cyclone center locations. It is found that tropical cyclone events considerably increase the occurrence of TTL clouds, in the form of cirrus clouds above a clear troposphere. The amount of TTL cloud ice, however, is found to be mostly contributed by overshooting deep convections that penetrate the bottom of TTL. Using the synergistic retrieval method, we find a vertically oscillating pattern of temperature anomalies above tropical cyclones, with warming beneath the cloud top (around 16 km) and cooling above. The atmospheric column above 16 km is generally hydrated by overshooting convections, although dehydration is detected above non-overshooting TTL clouds. Above overshooting deep convections, the column-integrated water vapor is found to be on average 40 % higher than the climatology. Moreover, the TTL above tropical cyclones is cooled due to longwave radiative cooling. The radiative heating rates above cyclones are well differentiated by the brightness temperature of a satellite infrared channel in the window band. Using radiative calculations, it is found that TTL hydration is usually associated with radiative cooling of the TTL, which inhibits the diabatic ascent of moist air. The radiative balance of the TTL under the impact of the cyclone, therefore, is not in favor of maintaining the moist anomalies in the TTL or transporting water vertically to the stratosphere.
Aerosol reductions outweigh circulation changes for future improvements in Beijing haze
Authors: Guo Liang , Wilcox Laura J. , Bollasina Massimo , Turnock Steven T. , Lund Marianne T. , Zhang Lixia
Published: April 2021

Abstract. Despite local emission reductions, severe haze events remain a serious issue in Beijing. Previous studies have suggested that both greenhouse gas increases and aerosol decreases are likely to increase the frequency of weather patterns conducive to haze events. However, the combined effect of atmospheric circulation changes and aerosol and precursor emission changes on Beijing haze remains unclear. We use the Shared Socioeconomic Pathways (SSPs) to explore the effects of aerosol and greenhouse gas emission changes on both haze weather and Beijing haze itself. We confirm that the occurrence of haze weather patterns is likely to increase in future under all SSPs, and show that even though aerosol reductions play a small role, greenhouse gas increases are the main driver, especially during the second half of the 21st century. However, the severity of the haze events decreases on decadal timescales by as much as 70 % by 2100. The main influence on the haze itself is the reductions in local aerosol emissions, which outweigh the effects of changes in atmospheric circulation patterns. This demonstrates that aerosol reductions are beneficial, despite their influence on the circulation.
Mass spectral characterization of secondary organic aerosol from urban lifestyle sources emissions
Authors: Zhu Wenfei , Guo Song , Hu Min , Zhang Zirui , Wang Hui , Yu Ying , Chen Zheng , Shen Ruizhe , Tan Rui , Song Kai , Liu Kefan , Tang Rongzhi , Liu Yi , Lou Shengrong , Li Yuanju , Zhang Wenbin , Zhang Zhou , Shuai Shijin , Xu Hongming , Li Shuangde , Chen Yunfa , Canonaco Francesco , Prévôt Andre S. H.
Published: April 2021

Abstract. In the present work, we conducted experiments of secondary organic aerosol (SOA) formation from urban lifestyle sources (cooking and vehicle) to characterize the mass spectral features of primary organic aerosol (POA) and SOA using an high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Our results showed that the cooking styles have greater impact on aged COA mass spectra than oxidation condition. However, the oxidation conditions affect the aged HOA spectra more significantly than vehicle operation conditions. In our study, we use mass spectra similarity analysis and positive matrix factorization (PMF) analysis to establish the POA and SOA mass spectra of these two typical lifestyle sources. These mass spectra are used as source constraints in a multilinear engine (ME-2) model to apportion the OA sources in the atmosphere. Comparing with the traditional ambient PMF results, the improved ME-2 model can better quantify the contribution of POA and SOA from life-style sources. Our work, for the first time, establishes the vehicle and cooking SOA source profiles, and can be further used in the OA source apportionment in the ambient atmosphere.
Non-equilibrium interplay between gas–particle partitioning and multiphase chemical reactions of semi-volatile compounds: mechanistic insights and practical implications for atmospheric modeling of polycyclic aromatic hydrocarbons
Authors: Wilson Jake , Pöschl Ulrich , Shiraiwa Manabu , Berkemeier Thomas
Published: April 2021

Abstract. Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic air pollutants. The dispersion of PAHs in the atmosphere is influenced by gas–particle partitioning and chemical loss. These processes are closely interlinked and may occur at vastly differing timescales, which complicates their mathematical description in chemical transport models. Here, we use a kinetic model that explicitly resolves mass transport and chemical reactions in the gas and particle phases to describe and explore the dynamic and non-equilibrium interplay of gas–particle partitioning and chemical losses of PAHs on soot particles. We define the equilibration timescale τeq of gas–particle partitioning as the e-folding time for relaxation of the system to the partitioning equilibrium. We find this metric to span from seconds to hours depending on temperature, particle surface area, and the type of PAH. The equilibration time can be approximated using a time-independent equation, τeq≈1kdes+kads, which depends on the desorption rate coefficient kdes and adsorption rate coefficient kads, both of which can be calculated from experimentally accessible parameters. The model reveals two regimes in which different physical processes control the equilibration timescale: a desorption-controlled and an adsorption-controlled regime. In a case study with the PAH pyrene, we illustrate how chemical loss can perturb the equilibrium particulate fraction at typical atmospheric concentrations of O3 and OH. For the surface reaction with O3, the perturbation is significant and increases with the gas-phase concentration of O3. Conversely, perturbations are smaller for reaction with the OH radical, which reacts with pyrene on both the surface of particles and in the gas phase. Global and regional chemical transport models typically approximate gas–particle partitioning with instantaneous-equilibration approaches. We highlight scenarios in which these approximations deviate from the explicitly coupled treatment of gas–particle partitioning and chemistry presented in this study. We find that the discrepancy between solutions depends on the operator-splitting time step and the choice of time step can help to minimize the discrepancy. The findings and techniques presented in this work not only are relevant for PAHs but can also be applied to other semi-volatile substances that undergo chemical reactions and mass transport between the gas and particle phase.
PARAFOG v2.0: a near real-time decision tool to support nowcasting fog formation events at local scales
Authors: Ribaud Jean-François , Haeffelin Martial , Dupont Jean-Charles , Drouin Marc-Antoine , Toledo Felipe , Kotthaus Simone
Published: April 2021

Abstract. An improved version of the near-real time decision tool PARAFOG (PFG2) is presented to retrieve pre-fog alert levels and to discriminate between radiation (RAD) and stratus lowering (STL) fog situations. PFG2 has two distinct modules to monitor the physical processes involved in RAD and STL fog formation and is evaluated at European sites. The modules are based on innovative fuzzy logic algorithms to retrieve fog alert levels (low, moderate, high) specific to RAD/STL conditions, minutes to hours prior to fog onset. The PFG2-RAD module assesses also the thickness of the fog. Both the PFG2-RAD and PFG2-STL modules rely on the combination of visibility observations and automatic lidar and ceilometer (ALC) measurements. The overall performance of the PFG2-RAD and -STL modules is evaluated based on 9 years of measurements at the SIRTA observatory near Paris and up to two fog seasons at the Paris-Roissy, Vienna, Munich and Zurich airports. At all sites, pre-fog alert levels retrieved by PFG2 are found to be consistent with the local weather analysis. The advanced PFG2 algorithm performs with a hit rate of about 100 % for both considered fog types, and presents a false alarm ratio on the order of 10 % (30 %) for RAD (STL) fog situations. Finally, the first high alerts that result in a subsequent fog event are found to occur for periods of time ranging from −120 minutes to fog onset, with first high alerts occurring earlier for RAD than STL cases.
Effects of black carbon morphology on brown carbon absorption estimation: from numerical aspects
Authors: Luo Jie , Zhang Yongming , Zhang Qixing
Published: April 2021

Abstract. In this work, we developed a numerical method to investigate the effects of black carbon (BC) morphology on the estimation of brown carbon (BrC) absorption using the absorption Ångström exponent (AAE) methods. Pseudo measurements of the total absorption were generated based on several morphologically mixed BC models, then the BrC absorption was inferred based on different BC AAE methods. By investigating the estimated BrC absorption at different parameters, we have demonstrated under what conditions the AAE methods can provide good or bad estimations. As recent studies have shown that both externally and internally mixed BC still exhibits a relatively small fractal dimension value, the AAE = 1 method is still a reasonable method to estimate the BrC absorption as the AAE of fluffy BC does not deviate significantly from 1. However, the deviation between the “true” and the estimated BrC mass absorption cross section (MAC) should also be carefully considered as sometimes the MAC deviation estimated using the AAE = 1 method can reach a value that is comparable to the true BrC MAC for internally mixed particles. The Mie AAE method can just provide relatively reasonable estimations for small particles, and the BrC absorption deviations estimated using the Mie AAE methods are rather substantial for large particles. If the BC core still exhibits a fluffy structure, the deviation between the true and the estimated BrC MAC can reach 4.8 and 5.8 m2/g for large externally and internally mixed particles, respectively. Even for a compact BC core, the BrC MAC deviation estimated using the Mie AAE method can reach approximately 2.8 m2/g when the BC size is large. By comparing the AAE of spherical BC and detailed BC models, we found that the AAE does not deviate significantly from 1 if BC presents a fluffy fractal structure, while it varies considerably with particle size if BC exhibits a spherical structure, and the AAE value of spherical BC can vary from a negative value to approximately 1.4. The precalculated wavelength dependence of AAE (WDA) method does not necessarily improve the estimations. In many cases, the WDA method even provides a worse estimation than the BC AAE =1 and Mie AAE methods. Our results showed that the WDA does not deviate significantly from 0 if the BC core presents a fluffy structure, while the WDA of spherical BC can vary significantly as the particle size changes. The deviation between the true and the estimated BrC MAC using the WDA method can reach approximately 9 m2/g for externally mixed particles, which is far more than BrC MAC itself. As recent studies have shown that BC commonly exhibits a fluffy structure but not a spherical structure, the estimation of BrC absorption based on the AAE method should carefully consider the effects of BC morphologies.
Fluxes from soil moisture measurements (FluSM v1.0): a data-driven water balance framework for permeable pavements
Authors: Schaffitel Axel , Schuetz Tobias , Weiler Markus
Published: April 2021

Abstract. Water fluxes at the soil–atmosphere interface are a key piece of
information for studying the terrestrial water cycle. However, measuring and
modeling water fluxes in the vadose zone poses great challenges. While
direct measurements require costly lysimeters, common soil hydrologic models
rely on a correct parametrization, a correct representation of the involved
processes, and the selection of correct initial and boundary conditions.
In contrast to lysimeter measurements, soil moisture measurements are
relatively cheap and easy to perform. Using such measurements, data-driven
approaches offer the possibility to derive water fluxes directly. Here we
present FluSM (fluxes from soil
moisture measurements), which is a simple, parsimonious and robust
data-driven water balancing framework. FluSM requires only a single input
parameter (the infiltration rate) and is especially valuable for cases where
the application of Richards-based models is critical. Since permeable
pavements (PPs) present such a case, we apply FluSM on a recently published
soil moisture data set to obtain the water balance of 15 different PPs over a
period of 2 years. Consistent with findings from previous studies, our
results show that vertical drainage dominates the water balance of PPs,
while surface runoff plays only a minor role. An additional uncertainty
analysis demonstrates the ability of the FluSM-approach for water balance
studies, since input and parameter uncertainties only have a small effect on
the characteristics of the derived water balances. Due to the lack of data
on the hydrologic behavior of PPs under field conditions, our results are of
special interest for urban hydrology.
Air Control Toolbox (ACT_v1.0): a machine learning flexible surrogate model to explore mitigation scenarios in air quality forecasts
Authors: Colette Augustin , Rouïl Laurence , Meleux Frédérik , Lemaire Vincent , Raux Blandine
Published: April 2021

Abstract. We introduce the first toolbox that allows exploring the benefit of air pollution mitigation scenarios in the every-day air quality forecasts through a web interface. Chemistry-transport models (CTMs) are required to forecast air pollution episodes and assess the benefit that shall be expected from mitigation strategies. However, their complexity prohibits offering a high level of flexibility. The Air Control Toolbox relies on machine learning methods to cope with this limitation. It consists of a surrogate model trained on a limited set of sensitivity scenarios to allow exploring any combination of mitigation measures. As such we take the best of the physical and chemical complexity of CTMs, operated on high performance computers for the everyday forecast, but we approximate a simplified response function that can be operated through a website to emulate the main sensitivities of the atmospheric system for a given day and location. The numerical experimental plan to design the structure of the surrogate model is detailed by increasing level of complexity. The selected structure of the surrogate is a quadrivariate polynomial of first order for residential heating emissions, and second order for agriculture, industry and traffic emissions with three interaction terms. It is fitted to 12 sensitivity CTM simulations, at each grid point and every day for PM10, PM2.5, O3 (both as daily mean and daily maximum) and NO2. The validation study demonstrates that we can keep relative errors below 2 % at 95 % of the grid points and days for all pollutants. Various applications of the toolbox are presented for air quality episode analysis, source apportionment, and chemical regime analysis.
FORest Canopy Atmosphere Transfer (FORCAsT) 2.0: model updates and evaluation with observations at a mixed forest site
Authors: Wei Dandan , Alwe Hariprasad D. , Millet Dylan B. , Bottorff Brandon , Lew Michelle , Stevens Philip S. , Shutter Joshua D. , Cox Joshua L. , Keutsch Frank N. , Shi Qianwen , Kavassalis Sarah C. , Murphy Jennifer G. , Vasquez Krystal T. , Allen Hannah M. , Praske Eric , Crounse John D. , Wennberg Paul O. , Shepson Paul B. , Bui Alexander A. T. , Wallace Henry W. , Griffin Robert J. , May Nathaniel W. , Connor Megan , Slade Jonathan H. , Pratt Kerri A. , Wood Ezra C. , Rollings Mathew , Deming Benjamin L. , Anderson Daniel C. , Steiner Allison L.
Published: April 2021

Abstract. The FORCAsT (FORest Canopy Atmosphere Transfer) model version 1.0 is updated to FORCAsT 2.0 by implementing five major changes, including (1) a change to the operator splitting, separating chemistry from emission and dry deposition, which reduces the run time of the gas-phase chemistry by 70 % and produces a more realistic in-canopy profile for isoprene; (2) a modification of the eddy diffusivity parameterization to produce greater and more realistic vertical mixing in the boundary layer, which ameliorates the unrealistic simulated end-of-day peaks in isoprene under well-mixed conditions and improves daytime air temperature; (3) updates to dry deposition velocities with available measurements; (4) implementation of the Reduced Caltech isoprene mechanism (RCIM) to reflect the current knowledge of isoprene oxidation; and (5) extension of the aerosol module to include isoprene-derived aerosol (iSOA) formation. Along with the operator splitting, modified vertical mixing and dry deposition, RCIM improves the estimation of first generation isoprene oxidation products (methyl vinyl ketone and methacrolein) and some second generation products (such as isoprene epoxydiols). Inclusion of isoprene in the aerosol module in FORCAsT 2.0 leads to a 7 % mass yield of iSOA. The most important iSOA precursors are IEPOX and tetrafunctionals, which together account for > 86 % of total iSOA. The iSOA formed from organic nitrates are more important in the canopy, accounting for 11 % of the total iSOA. The tetrafunctionals compose up to 23 % of the total iSOA formation, highlighting the importance of the fate (i.e. dry deposition and gas-phase chemistry) of later-generation isoprene oxidation products in estimating iSOA formation.
Inundation prediction in tropical wetlands from JULES-CaMa-Flood global land surface simulations
Authors: Marthews Toby Richard , Dadson Simon J. , Clark Douglas B. , Blyth Eleanor M. , Hayman Garry , Yamazaki Dai , Becher Olivia R. E. , Martínez-de la Torre Alberto , Prigent Catherine , Jiménez Carlos
Published: April 2021

Abstract. Wetlands play a key role in hydrological and biogeochemical cycles and provide multiple ecosystem services to society. However, reliable data on the extent of global inundated areas and the magnitude of their contribution to local hydrological dynamics remain surprisingly uncertain. Global hydrological models and Land Surface Models (LSMs) include only the most major inundation sources and mechanisms, therefore quantifying the uncertainties in available data sources remains a challenge. We address these problems by taking a leading global data product on inundation extents (GIEMS) and matching against predictions from a sophisticated global hydrodynamic model (CaMa-Flood) that uses runoff data generated from the JULES land surface model. The ability of the model to reproduce patterns and dynamics showed by the observational product is assessed in a number of case studies across the tropics (including the Sudd, Pantanal, Congo and Amazon), which show that it performs well in large wetland regions, with a good match between corresponding seasonal cycles. However, at finer spatial scale, water inputs (e.g. groundwater inflow to wetland) may become underestimated in comparison to water outputs (e.g. infiltration and evaporation from wetland); or the opposite may occur, depending on the wetland concerned. Additionally, some wetlands display a clear spatial displacement between observed and simulated inundation as a result of over- or under-estimation of overbank flooding upstream. This study provides timely data that can contribute to our current ability to make critical predictions of inundation events at both regional and global levels.
On the selection of precipitation products for the regionalisation of hydrological model parameters
Authors: Baez-Villanueva Oscar M. , Zambrano-Bigiarini Mauricio , Mendoza Pablo A. , McNamara Ian , Beck Hylke E. , Thurner Joschka , Nauditt Alexandra , Ribbe Lars , Thinh Nguyen Xuan
Published: April 2021

Abstract. Over the past years, novel parameter regionalisation techniques have been developed to predict streamflow in data-scarce regions. In this paper, we examined how the choice of gridded daily precipitation (P) products affects individual catchment calibration and verification, as well as the relative performance of three well-known regionalisation techniques (spatial proximity, feature similarity, and parameter regression) over 100 near-natural catchments with diverse hydrological regimes across Chile. We configured and calibrated a conceptual semi-distributed HBV-like hydrological model for each catchment, using four P products (ERA5, MSWEPv2.8, RF-MEPv2, and CR2MET), and two objective functions. The three regionalisation techniques were applied and evaluated for each combination of P product and objective function, using a leave-one-out cross-validation procedure. Despite differences in the spatio-temporal distribution of P quantities, all P products provided good performance during calibration (median KGE's > 0.77), two independent verification periods (median KGE's > 0.70 and 0.61, for near normal and dry conditions, respectively), and regionalisation results (with median KGE's for the best method ranging from 0.56 to 0.63). Our results suggest that model calibration is able to compensate, to some extent, differences between forcing datasets, and that the spatial resolution of P products does not substantially affect the regionalisation performance. Overall, feature similarity provided the best results, followed closely by spatial proximity, while parameter regression performed the worst, thus reinforcing the importance of transferring complete parameter sets to ungauged catchments. Our results suggest that: i) merging P products and ground-based measurements does not necessarily translate into an improved hydrological modelling performance; ii) a P product that provides the best individual model performance during calibration and verification does not necessarily provide the best performance in terms of parameter regionalisation; and iii) the hydrological regime affects the performance of regionalisation methods, with rain-dominated catchments with a snow component performing the best over Chile for spatial proximity and feature similarity.
Interfacial supercooling and the precipitation of hydrohalite in frozen NaCl solutions as seen by X-ray absorption spectroscopy
Authors: Bartels-Rausch Thorsten , Kong Xiangrui , Orlando Fabrizio , Artiglia Luca , Waldner Astrid , Huthwelker Thomas , Ammann Markus
Published: April 2021

Abstract. Laboratory experiments are presented on the phase change
at the surface of sodium chloride–water mixtures at temperatures between
259 and 241 K. Chloride is a ubiquitous component of polar coastal surface
snow. The chloride embedded in snow is involved in reactions that modify the
chemical composition of snow as well as ultimately impact the budget of
trace gases and the oxidative capacity of the overlying atmosphere.
Multiphase reactions at the snow–air interface have been of particular
interest in atmospheric science. Undoubtedly, chemical reactions proceed
faster in liquids than in solids; but it is currently unclear when such
phase changes occur at the interface of snow with air. In the experiments
reported here, a high selectivity to the upper few nanometres of the frozen
solution–air interface is achieved by using electron yield near-edge
X-ray absorption fine-structure (NEXAFS) spectroscopy. We find that sodium
chloride at the interface of frozen solutions, which mimic sea-salt deposits
in snow, remains as supercooled liquid down to 241 K. At this temperature,
hydrohalite exclusively precipitates and anhydrous sodium chloride is not
detected. In this work, we present the first NEXAFS spectrum of hydrohalite.
The hydrohalite is found to be stable while increasing the temperature
towards the eutectic temperature of 252 K. Taken together, this study
reveals no differences in the phase changes of sodium chloride at the
interface as compared to the bulk. That sodium chloride remains liquid at
the interface upon cooling down to 241 K, which spans the most common
temperature range in Arctic marine environments, has consequences for
interfacial chemistry involving chlorine as well as for any other reactant
for which the sodium chloride provides a liquid reservoir at the interface
of environmental snow. Implications for the role of surface snow in
atmospheric chemistry are discussed.