bluuebunny/crossref_metadata_2025 huggingface dataset:
PRRT as an alternative method of treatment in patient with glucagonoma syndrome: A case report
Authors: Popławska-Kita A. , Szyszkowska A. , Brelska P. , Kowalczuk M. , Szostek A. , Popławski Ł. , Siewko K. , Szelachowska M. , Kamiński G. , Werel D. , Górska M.
Published: July 2017

Introduction: Glucagonoma is a rare pancreatic neuroendocrine tumor derived from alpha-cells of the islet of Langerhans. Due to oversecretion of glucagon it is associated with a characteristic paraneoplastic phenomenon, called glucagonoma syndrome, which consists of necrolytic migratory erythema (NME), weight loss, diabetes mellitus, diarrhea, normochromic normocytic anemia, deep vein thrombosis or pulmonary embolism and neuropsychiatric disturbances. Treatment modalities include surgical removal of tumor, somatostatin analogs and peptide receptor radionuclide therapy (PRRT).
Case report: We present a case of 61-year-old woman diagnosed with glucagonoma in April 2012. Initially, body-caudal pancreatomy and resection of regional lymph nodes were performed. Five months after surgery, a PET-CT scan detected pathological mass with expression of somatostatin receptors in pancreatic body and metastases to regional lymph nodes. What is more, since April 2014 the patient had complained about persistent pruritus of the entire body. At present, due to the nonsurgical pancreatic mass and metastases she is treated with somatostatin analogs and PRRT. During this therapy the pruritus had decreased and currently there is no sign of cutaneous disease. Moreover, reduction of tumor size was obtained.
Conclusions: PRRT may reduce tumor size and by reducing bothersome symptoms substantially improve the quality of life in patients with SSTR-positive tumors
Desfechos clínicos de pacientes submetidos à cirurgia cardíaca em um hospital do noroeste do Rio Grande do Sul
Authors: Santos Miquéias Bogado Kasctin dos , Silveira Camila Rieffel , Moraes Maria Antonieta Pereira de , Souza Emiliane Nogueira de
Published: July 2017

Objetivo: Analisar os desfechos clínicos dos pacientes submetidos à cirurgia cardíaca em um hospital de alta complexidade. Método: Estudo descritivo, longitudinal histórico, no qual foram analisados prontuários de pacientes submetidos à cirurgia cardíaca no período de um ano. Resultados: Entre os 137 prontuários analisados, a cirurgia de revascularização do miocárdio foi a mais prevalente 85(62%). A média de tempo de internação na unidade de terapia intensiva foi de 2,93±4,53 dias, e na unidade de internação clinica/cirúrgica foi de 3,77±3,53 dias. As drogas mais utilizadas foram as vasoativas. As intercorrências mais prevalentes, no período pós-operatório, foram a hipotensão arterial 50(36,6%), sangramento 17(12,4%) e hiperglicemia 10(7,3%).  O tempo médio de permanência do dreno de tórax foi de 51h43min, do uso de ventilação mecânica foi de 16h38min e do tubo orotraqueal foi de 16h48min. Conclusão: Os principais desfechos clínicos no pós-operatório de cirurgia cardíaca relacionam-se com a condição hemodinâmica do paciente.
Satisfação no trabalho de enfermeiros em um hospital universitário
Authors: Morais Marisa Pires de , Martins Júlia Trevisan , Galdino Maria José Quina , Robazzi Maria Lucia Do Carmo Cruz , Trevisan Gabriela Schmitt
Published: July 2017

Objetivo: identificar os fatores de satisfação no trabalho de enfermeiros em um hospital universitário. Método: pesquisa qualitativa, descritiva e exploratória realizada com 15 enfermeiros em um hospital universitário do norte do Paraná. A coleta de dados ocorreu no período de novembro de 2011 a maio de 2012, por entrevista semiestruturada e as falas foram submetidas à análise de conteúdo na modalidade temática. Resultados: emergiu uma categoria temática denominada de fatores de satisfação no trabalho do enfermeiro com sete subcategorias: a remuneração e incentivo pela instituição, a carga horária de trabalho, o trabalho em equipe, o reconhecimento pelo trabalho realizado, a autonomia e resolubilidade para prestar assistência, o cuidar do paciente e o trabalho em instituição pública. Conclusão: identificar os fatores de satisfação no trabalho do enfermeiro pode contribuir para a sua manutenção ou maximização com vistas a proporcionar uma melhorar qualidade de vida no trabalho.
A compreensão de professores de educação física acerca dos métodos de ensino e das propostas críticas em escolas campos de estágio
Authors: Bianco Montegutti Berti Mirelli
Published: July 2017

O objetivo geral desta pesquisa foi analisar quais os conhecimentos de professores de Educação Física, que atuam em escolas de Criciúma/SC, acerca dos métodos de ensino e das propostas pedagógicas críticas da Educação Física. Assim, efetivamos uma pesquisa de campo, tendo como instrumento de coleta de dados, um questionário. Participaram da pesquisa nove professores de Educação Física. Concluímos que a maioria desses professores compreende a importância e a finalidade dos métodos de ensino. Alguns professores, porém, confundem métodos de ensino compropostas pedagógicas da Educação Física. Ademais, seis desses professores dizem organizar suas aulas por meio da proposta crítico-superadora. Palavras chave: Métodos de ensino. Educação Física escolar. Propostas críticas.
As contribuições e implicações do PIBID na formação continuada em serviço de professores(as) supervisores(as)
Authors: Piccolo Becker Eriques , Valau Keller Raiara , Sawitzki Rosalvo Luís
Published: July 2017

Este trabalho analisa as contribuições e implicações do subprojeto PIBID Educação Física na Formação Continuada (FC) em serviço de Professores Supervisores (PS). Como metodologia, foi utilizada observações manifestadas semanalmente em reuniões desse subprojeto. Como resultados, percebemos a importância da participação dos PS no PIBID, pois ela traz muitas contribuições em conhecimentos e valores que enriquecem esse processo formativo, discutindo com os demais envolvidos no subprojeto possibilidades para melhorar a prática pedagógica docente. Concluímos que a FC em serviço é uma alternativa que pode contribuir para melhor compreender a prática pedagógica e o campo de atividade docente.
Experimental Studies on Seakeeping and Maneuverability of Ships in Adverse Weather Conditions
Authors: Sprenger Florian , Maron Adolfo , Delefortrie Guillaume , van Zwijnsvoorde Thibaut , Cura-Hochbaum Andres , Lengwinat Antonio , Papanikolaou Apostolos
Published: July 2017

The introduction of the energy efficiency design index (EEDI), which is applicable for various types of new-built ships after January 1,2013, raised concerns regarding the sufficiency of propulsion power and steering devices to maintain maneuverability in adverse conditions. This was the motivation for the initiation of the EU research project SHOPERA (Energy Efficient Safe SHip OPERAtion, 2013–2016, http://www.shopera.org). The aim of this article is the development of suitable methods, tools, and guidelines to effectively address the above concerns and to enable safe and green shipping. Within the framework of SHOPERA, a comprehensive experimental program of more than 1300 different model tests for three ship hulls of different geometry and hydrodynamic characteristics has been conducted by four leading European maritime experimental research institutes: MARINTEK, Norway; CEHIPAR, Spain; Technische Universität Berlin, Germany; and Flanders Hydraulics Research, Belgium. The tested hull types refer to two public domain designs, namely the KVLCC2 tanker and the Duisburg Test Case (DTC) container ship, as well as to a small RoPax ferry design, which is a proprietary hull design of a member of the SHOPERA consortium. The conducted tests were distributed among the four research institutes to benefit from the unique possibilities of each facility and to gain added value by establishing data sets for the same hull model and test type at different under keel clearances. This article presents the scope of the SHOPERA model test program for the two public domain hull models—the KVLCC2 and the DTC. The main particulars and loading conditions for the two vessels as well as the experimental setup is provided to support the interpretation of the experimental data that is presented. The focus lies on the added resistance and drift forces at zero and moderate forward speed, propulsion, and rudder force tests in waves and the assessment of maneuverability of ships in waves, as compared to calm water conditions.
Pro-death NMDA receptor signaling is promoted by the GluN2B C-terminus independently of Dapk1
Authors: McQueen Jamie , Ryan Tomás J , McKay Sean , Marwick Katie , Baxter Paul , Carpanini Sarah M , Wishart Thomas M , Gillingwater Thomas H , Manson Jean C , Wyllie David J A , Grant Seth G N , McColl Barry W , Komiyama Noboru H , Hardingham Giles E
Published: July 2017

Aberrant NMDA receptor (NMDAR) activity contributes to several neurological disorders, but direct antagonism is poorly tolerated therapeutically. The GluN2B cytoplasmic C-terminal domain (CTD) represents an alternative therapeutic target since it potentiates excitotoxic signaling. The key GluN2B CTD-centred event in excitotoxicity is proposed to involve its phosphorylation at Ser-1303 by Dapk1, that is blocked by a neuroprotective cell-permeable peptide mimetic of the region. Contrary to this model, we find that excitotoxicity can proceed without increased Ser-1303 phosphorylation, and is unaffected by Dapk1 deficiency in vitro or following ischemia in vivo. Pharmacological analysis of the aforementioned neuroprotective peptide revealed that it acts in a sequence-independent manner as an open-channel NMDAR antagonist at or near the Mg2+ site, due to its high net positive charge. Thus, GluN2B-driven excitotoxic signaling can proceed independently of Dapk1 or altered Ser-1303 phosphorylation.
Defining the biological basis of radiomic phenotypes in lung cancer
Authors: Grossmann Patrick , Stringfield Olya , El-Hachem Nehme , Bui Marilyn M , Rios Velazquez Emmanuel , Parmar Chintan , Leijenaar Ralph TH , Haibe-Kains Benjamin , Lambin Philippe , Gillies Robert J , Aerts Hugo JWL
Published: July 2017

Medical imaging can visualize characteristics of human cancer noninvasively. Radiomics is an emerging field that translates these medical images into quantitative data to enable phenotypic profiling of tumors. While radiomics has been associated with several clinical endpoints, the complex relationships of radiomics, clinical factors, and tumor biology are largely unknown. To this end, we analyzed two independent cohorts of respectively 262 North American and 89 European patients with lung cancer, and consistently identified previously undescribed associations between radiomic imaging features, molecular pathways, and clinical factors. In particular, we found a relationship between imaging features, immune response, inflammation, and survival, which was further validated by immunohistochemical staining. Moreover, a number of imaging features showed predictive value for specific pathways; for example, intra-tumor heterogeneity features predicted activity of RNA polymerase transcription (AUC = 0.62, p=0.03) and intensity dispersion was predictive of the autodegration pathway of a ubiquitin ligase (AUC = 0.69, p<10-4). Finally, we observed that prognostic biomarkers performed highest when combining radiomic, genetic, and clinical information (CI = 0.73, p<10-9) indicating complementary value of these data. In conclusion, we demonstrate that radiomic approaches permit noninvasive assessment of both molecular and clinical characteristics of tumors, and therefore have the potential to advance clinical decision-making by systematically analyzing standard-of-care medical images.
In vitro assessment of anti-proliferative effect induced by α-mangostin from Cratoxylum arborescens on HeLa cells
Authors: El habbash Aisha I. , Mohd Hashim Najihah , Ibrahim Mohamed Yousif , Yahayu Maizatulakmal , Omer Fatima Abd Elmutaal , Abd Rahman Mashitoh , Nordin Noraziah , Lian Gwendoline Ee Cheng
Published: July 2017

Natural medicinal products possess diverse chemical structures and have been an essential source for drug discovery. Therefore, in this study, α-mangostin (AM) is a plant-derived compound was investigated for the apoptotic effect on human cervical cancer cells (HeLa). The cytotoxic effects of AM on the viability of HeLa and human normal ovarian cell line (SV40) were evaluated by using MTT assay. Results showed that AM inhibited HeLa cells viability at concentration- and time-dependent manner with IC50 value of 24.53 ± 1.48 µM at 24 h. The apoptogenic effects of AM on HeLa were assessed using fluorescence microscopy analysis. The effect of AM on cell proliferation was also studied through clonogenic assay. ROS production evaluation, flow cytometry (cell cycle) analysis, caspases 3/7, 8, and 9 assessment and multiple cytotoxicity assays were conducted to determine the mechanism of cell apoptosis. This was associated with G2/M phase cell cycle arrest and elevation in ROS production. AM induced mitochondrial apoptosis which was confirmed based on the significant increase in the levels of caspases 3/7 and 9 in a dose-dependent manner. Furthermore, the MMP disruption and increased cell permeability, concurrent with cytochrome c release from the mitochondria to the cytosol provided evidence that AM can induce apoptosis via mitochondrial-dependent pathway. AM exerted a remarkable antitumor effect and induced characteristic apoptogenic morphological changes on HeLa cells, which indicates the occurrence of cell death. This study reveals that AM could be a potential antitumor compound on cervical cancer in vitro and can be considered for further cervical cancer preclinical and in vivo testing.
A laid-back trip through the Hennigian Forests
Authors: Mavrodiev Evgeny V. , Dell Christopher , Schroder Laura
Published: July 2017

Background

This paper is a comment on the idea of matrix-free Cladistics. Demonstration of this idea’s efficiency is a major goal of the study. Within the proposed framework, the ordinary (phenetic) matrix is necessary only as “source” of Hennigian trees, not as a primary subject of the analysis. Switching from the matrix-based thinking to the matrix-free Cladistic approach clearly reveals that optimizations of the character-state changes are related not to the real processes, but to the form of the data representation.

Methods

We focused our study on the binary data. We wrote the simple ruby-based script FORESTER version 1.0 that helps represent a binary matrix as an array of the rooted trees (as a “Hennigian forest”). The binary representations of the genomic (DNA) data have been made by script1001. The Average Consensus method as well as the standard Maximum Parsimony (MP) approach has been used to analyze the data.

Principle findings

The binary matrix may be easily re-written as a set of rooted trees (maximalrelationships). The latter might be analyzed by the Average Consensus method. Paradoxically, this method, if applied to the Hennigian forests,in principlecan help to identify cladesdespitethe absence of the direct evidence from the primary data. Our approach may handle the clock- or non clock-like matrices, as well as the hypothetical, molecular or morphological data.

Discussion

Our proposal clearly differs from the numerous phenetic alignment-free techniques of the construction of the phylogenetic trees. Dealing with the relations, not with the actual “data” also distinguishes our approach from all optimization-based methods, if the optimization is defined as a way to reconstruct the sequences of the character-state changes on a tree, either the standard alignment-based techniques or the “direct” alignment-free procedure. We are not viewing our recent framework as an alternative to the three-taxon statement analysis (3TA), but there are two major differences between our recent proposal and the 3TA, as originally designed and implemented: (1) the 3TA deals with the three-taxon statements or minimal relationships. According to the logic of 3TA, the set of the minimal trees must be established as a binary matrix and used as an input for the parsimony program. In this paper, we operate directly with maximal relationships written just as trees, not as binary matrices, while also using the Average Consensus method instead of the MP analysis. The solely ‘reversal’-based groups can always be found by our method without the separate scoring of the putative reversals before analyses.
Using electroretinograms and multi-model inference to identify spectral classes of photoreceptors and relative opsin expression levels
Authors: Lessios Nicolas
Published: July 2017

Understanding how individual photoreceptor cells factor in the spectral sensitivity of a visual system is essential to explain how they contribute to the visual ecology of the animal in question. Existing methods that model the absorption of visual pigments use templates which correspond closely to data from thin cross-sections of photoreceptor cells. However, few modeling approaches use a single framework to incorporate physical parameters of real photoreceptors, which can be fused, and can form vertical tiers. Akaike’s information criterion (AICc) was used here to select absorptance models of multiple classes of photoreceptor cells that maximize information, given visual system spectral sensitivity data obtained using extracellular electroretinograms and structural parameters obtained by histological methods. This framework was first used to select among alternative hypotheses of photoreceptor number. It identified spectral classes from a range of dark-adapted visual systems which have between one and four spectral photoreceptor classes. These were the velvet worm,Principapillatus hitoyensis, the branchiopod water flea,Daphnia magna, normal humans, and humans with enhanced S-cone syndrome, a condition in which S-cone frequency is increased due to mutations in a transcription factor that controls photoreceptor expression. Data from the Asian swallowtail,Papilio xuthus, which has at least five main spectral photoreceptor classes in its compound eyes, were included to illustrate potential effects of model over-simplification on multi-model inference. The multi-model framework was then used with parameters of spectral photoreceptor classes and the structural photoreceptor array kept constant. The goal was to map relative opsin expression to visual pigment concentration. It identified relative opsin expression differences for two populations of the bluefin killifish,Lucania goodei. The modeling approach presented here will be useful in selecting the most likely alternative hypotheses of opsin-based spectral photoreceptor classes, using relative opsin expression and extracellular electroretinography.
CARACTERIZAÇÃO DE RESÍDUOS DA SUINOCULTURA, DA INDÚSTRIA TÊXTIL E DE URINA HUMANA PARA APLICAÇÃO COMO FERTILIZANTE
Authors: Aguida Leandro Mazzuco de , Depiné Haline , Oliveira Daniela Aparecida , Kaufmann Vander , Pinheiro Adilson
Published: July 2017

O uso dos resíduos orgânicos na agricultura é uma opção viável do ponto de vista agrícola e econômico em razão da ciclagem de nutrientes. No entanto, questionamentos são efetuados em relação aos impactos ambientais que podem ser gerados. O presente trabalho teve como objetivo quantificar as espécies químicas dos resíduos da suinocultura, da indústria têxtil e da urina humana, na perspectiva de seu reuso como fertilizante na atividade agrícola. Para a determinação das concentrações das espécies químicas, utilizou-se o cromatógrafo de troca iônica aniônica e catiônica e o analisador de carbono orgânico total para as concentrações de carbono das amostras. Os resultados indicaram que os dejetos líquidos suínos (DLS) e a urina humana podem suprir a necessidade de potássio em solos cujo teor de potássio é considerado de valor médio, enquanto o lodo têxtil apresentou valor 9 vezes menor. Para solos com teor muito baixo a aplicação de DLS e urina humana podem ser de 100 m³ ha-1 ano-1, enquanto em solos com teor médio de potássio, o DLS e urina humana tem que ser reduzidos pela metade. No caso do fósforo, a urina humana supre a necessidade quando o teor deste elemento no solo for médio, enquanto no DLS, o valor observado é 20 vezes menor e no lodo têxtil 37 vezes menor. Para atender a necessidade de solos com teor muito baixo, a urina humana pode ser aplicada a 100 m³. ha-1 ano-1, porém o DLS e lodo têxtil não atenderiam esta necessidade.
A Case of Poorly Differentiated Adenocarcinoma with Signet Ring Cell Carcinoma of the Duodenal Bulb: A Case Report
Authors: Hirano Kosuke , Yamagata Yukinori , Tatsuoka Teppei , Kubota Yawara , Saito Kazuyuki , Koketsu Shinichiro , Okuyama Takashi , Sugamata Yoshitake , Fujii Akiko , Ban Shinichi , Tagaya Nobumi , Sameshima Shinichi , Noie Tamaki , Oya Masatoshi
Published: July 2017

Duodenal cancers are rare. Histopathologically, most duodenal cancers are adenocarcinoma. Signet ring cell carcinoma (SRCC) is a rare tumor more commonly found in the stomach than at other sites in the digestive tract. SRCC is extremely uncommon in the duodenum, with most of these tumors occurring in the ampulla. Until now, there are few case reports of duodenal cancers with SRCC. To accumulate case reports, we report a rare case of nonampullary duodenal bulb SRCC. A 74-year-old man was admitted to our hospital with melena. Esophagogastroduodenoscopy (EGD) showed a duodenal bulb ulcer. He was treated with a proton pump inhibitor. However, 1 month later, he was readmitted to our hospital with epigastric pain and nausea. A second EGD examination showed an ulcer at the duodenal bulb. Biopsies taken from the ulcer showed SRCC. Distal gastrectomy and duodenal bulb resection were performed. Histologic examination of the specimen showed a type 4 lesion located from the duodenal bulb to the pyloric antrum. The tumor was composed of poorly differentiated adenocarcinoma (por) with SRCC. The distal margin of the duodenal bulb was invaded with tumor. Therefore, pancreatoduodenectomy was performed. One year after the initial operation, he is alive and had no relapse. We described a rare case of por with SRCC of the duodenal bulb. It is important to bear in mind that an ulcer following an abnormal clinical course should be biopsied, and we have to select a suitable operation in cases of duodenal bulb cancer.
Link between Indian monsoon rainfall and physical erosion in the Himalayan system during the Holocene
Authors: Joussain Ronan , Liu Zhifei , Colin Christophe , Duchamp‐Alphonse Stéphanie , Yu Zhaojie , Moréno Eva , Fournier Léa , Zaragosi Sébastien , Dapoigny Arnaud , Meynadier Laure , Bassinot Franck
Published: July 2017

Mineralogical and geochemical analyses conducted on cores located on the active channel‐levee system of the northern Bengal Fan are used to establish changes in the weathering pattern and the sediment transport of the Himalayan system, and evaluate the effect of Indian summer monsoon rainfall during the Holocene. Our data indicate that during the Holocene, sediments from the northern Bengal Fan originate mainly from the G‐B river system without any significant changes in the relative contribution of these rivers. From 9.8 to around 6 ka, relatively low smectite/(illite+chlorite) ratios and relatively high K/Si* ratios indicate high physical denudation rates of the Himalayan highlands together with a rapid transfer of the detrital material to the Bengal Fan. The period between 9.2 and 7 ka is associated to lower values of K/Si* and corresponds to the maximum of Indian monsoon rainfall which indicates a more important chemical weathering material that rapidly transits by the G‐B river system without a long storage in the Indo‐Gangetic plain. From 6.0 ka to present day, higher smectite/(illite+chlorite) ratio and lower K/Si* ratio document a gradual increase of sediments originated from the Indo‐Gangetic plain, characterized by higher degree of chemical weathering. During the last 2.5 ka, the drastic increase in the smectite/(illite+chlorite) ratio could be associated to enhanced alteration of the plain soils due to anthropogenic activity. The comparison of mineralogical and geochemical data with previous reconstructions of the Indian monsoon dynamic indicates a rapid response of erosion and sediment transfer of the G‐B river system to changes of monsoon rainfall intensity.
Do cosmic ray air showers initiate lightning?: A statistical analysis of cosmic ray air showers and lightning mapping array data
Authors: Hare B. M. , Dwyer J. R. , Winner L. H. , Uman M. A. , Jordan D. M. , Kotovsky D. A. , Caicedo J. A. , Wilkes R. A. , Carvalho F. L. , Pilkey J. T. , Ngin T. K. , Gamerota W. R. , Rassoul H. K.
Published: July 2017

It has been argued in the technical literature, and widely reported in the popular press, that cosmic ray air showers (CRASs) can initiate lightning via a mechanism known as relativistic runaway electron avalanche (RREA), where large numbers of high‐energy and low‐energy electrons can, somehow, cause the local atmosphere in a thundercloud to transition to a conducting state. In response to this claim, other researchers have published simulations showing that the electron density produced by RREA is far too small to be able to affect the conductivity in the cloud sufficiently to initiate lightning. In this paper, we compare 74 days of cosmic ray air shower data collected in north central Florida during 2013–2015, the recorded CRASs having primary energies on the order of 1016 eV to 1018 eV and zenith angles less than 38°, with Lightning Mapping Array (LMA) data, and we show that there is no evidence that the detected cosmic ray air showers initiated lightning. Furthermore, we show that the average probability of any of our detected cosmic ray air showers to initiate a lightning flash can be no more than 5%. If all lightning flashes were initiated by cosmic ray air showers, then about 1.6% of detected CRASs would initiate lightning; therefore, we do not have enough data to exclude the possibility that lightning flashes could be initiated by cosmic ray air showers.
Effect of grain sorting on gravel bed river evolution subject to cycled hydrographs: Bed load sheets and breakdown of the hydrograph boundary layer
Authors: An Chenge , Fu Xudong , Wang Guangqian , Parker Gary
Published: July 2017

The evolution of gravel bed rivers under cycled hydrographs and constant sediment supply is studied in this paper. With the aid of numerical modeling and flume experiments, previous research has indicated that under such water and sediment supply conditions, a river can reach a mobile‐bed equilibrium characterized by a hydrograph boundary layer (HBL) located near the upstream end of the river. The HBL defines the spatial region within which riverbed topography and grain size respond to the hydrograph, and downstream of which these bed characteristics are invariant. However, neither the governing physical mechanisms nor the general applicability of the HBL is yet well understood. In this paper, we implement a 1‐D morphodynamic model for this problem. The model is first validated with data for both flume experiments and numerical simulations. It is then implemented at field scale with grain size distributions varying from uniform sediment to very poorly sorted sediment mixtures. Our results show that the idea of an HBL is applicable in the case of uniform sediment, but breaks down in the case of poorly sorted sediment mixtures. In such cases, persistent low‐amplitude bed load sheets emerge along the entire channel reach, in addition to HBL‐like upstream boundary effects. Bed load sheets can be described as surface texture or grain size sorting waves in consonance with low‐amplitude elevation variations, and are ascribed to nonlinear advection terms in the governing equations that vanish for uniform sediment, but become significant when sediment is very poorly sorted.
Temporal variations in air permeability and soil CO2 flux in volcanic ash soils (island of Vulcano, Italy)
Authors: Camarda Marco , Prano Vincenzo , Cappuzzo Santo , Gurrieri Sergio , Valenza Mariano
Published: July 2017

Air permeability is a major physical factor affecting the advective transport of a gas through the soil, and variations in this parameter can strongly influence the emission of endogenous gases from the soil to the atmosphere. In this paper, we illustrated a new and simple method for measuring in situ air permeability based on the measurement of air pressure inside a special probe inserted into the soil. The method was designed and developed primarily to study the relationship between air permeability and the soil CO2 flux in an active volcanic area. The method was used for continuous monitoring of the air permeability at two different locations on the island of Vulcano. At the same time, the values of the atmospheric pressure, temperature, rain, and volumetric water content of the soil were also acquired to investigate their effect on soil air permeability and soil CO2 flux. The results showed that during the monitoring period, soil air permeability exhibited minor variations at each site, while larger variations in the soil CO2 flux were recorded. The effect of soil air permeability on soil CO2 flux was negligible at both sites, whereas a strong dependence of soil CO2 flux on volumetric water content and on atmospheric pressure was found. Furthermore, the variation in air permeability recorded at both sites was much lower than that predicted using some well‐known predictive models, showing that the relationship among different soil transport parameters is more complex in real field conditions than would be expected by semiempirical models.
Electron density extrapolation above F2 peak by the linear Vary‐Chap model supporting new Global Navigation Satellite Systems‐LEO occultation missions
Authors: Hernández‐Pajares Manuel , Garcia‐Fernàndez Miquel , Rius Antonio , Notarpietro Riccardo , von Engeln Axel , Olivares‐Pulido Germán , Aragón‐Àngel Àngela , García‐Rigo Alberto
Published: July 2017

The new radio‐occultation (RO) instrument on board the future EUMETSAT Polar System‐Second Generation (EPS‐SG) satellites, flying at a height of 820 km, is primarily focusing on neutral atmospheric profiling. It will also provide an opportunity for RO ionospheric sounding, but only below impact heights of 500 km, in order to guarantee a full data gathering of the neutral part. This will leave a gap of 320 km, which impedes the application of the direct inversion techniques to retrieve the electron density profile. To overcome this challenge, we have looked for new ways (accurate and simple) of extrapolating the electron density (also applicable to other low‐Earth orbiting, LEO, missions like CHAMP): a new Vary‐Chap Extrapolation Technique (VCET). VCET is based on the scale height behavior, linearly dependent on the altitude above hmF2. This allows extrapolating the electron density profile for impact heights above its peak height (this is the case for EPS‐SG), up to the satellite orbital height. VCET has been assessed with more than 3700 complete electron density profiles obtained in four representative scenarios of the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) in the United States and the Formosa Satellite Mission 3 (FORMOSAT‐3) in Taiwan, in solar maximum and minimum conditions, and geomagnetically disturbed conditions, by applying an updated Improved Abel Transform Inversion technique to dual‐frequency GPS measurements. It is shown that VCET performs much better than other classical Chapman models, with 60% of occultations showing relative extrapolation errors below 20%, in contrast with conventional Chapman model extrapolation approaches with 10% or less of the profiles with relative error below 20%.
Sixteen year variation of horizontal phase velocity and propagation direction of mesospheric and thermospheric waves in airglow images at Shigaraki, Japan
Authors: Takeo D. , Shiokawa K. , Fujinami H. , Otsuka Y. , Matsuda T. S. , Ejiri M. K. , Nakamura T. , Yamamoto M.
Published: July 2017

We analyzed the horizontal phase velocity of gravity waves and medium‐scale traveling ionospheric disturbances (MSTIDs) by using the three‐dimensional fast Fourier transform method developed by Matsuda et al. (2014) for 557.7 nm (altitude: 90–100 km) and 630.0 nm (altitude: 200–300 km) airglow images obtained at Shigaraki MU Observatory (34.8°N, 136.1°E, dip angle: 49°) over ∼16 years from 16 March 1999 to 20 February 2015. The analysis of 557.7 nm airglow images shows clear seasonal variation of the propagation direction of gravity waves in the mesopause region. In spring, summer, fall, and winter, the peak directions are northeastward, northeastward, northwestward, and southwestward, respectively. The difference in east‐west propagation direction between summer and winter is probably caused by the wind filtering effect due to the zonal mesospheric jet. Comparison with tropospheric reanalysis data shows that the difference in north‐south propagation direction between summer and winter is caused by differences in the latitudinal location of wave sources due to convective activity in the troposphere relative to Shigaraki. The analysis of 630.0 nm airglow images shows that the propagation direction of MSTIDs is mainly southwestward with a minor northeastward component throughout the 16 years. A clear negative correlation is seen between the yearly power spectral density of MSTIDs and F10.7 solar flux. This negative correlation with solar activity may be explained by the linear growth rate of the Perkins instability and secondary wave generation of gravity waves in the thermosphere.
Peculiarities of VLF wave propagation in the Earth's magnetosphere in the presence of artificial large‐scale inhomogeneity
Authors: Pasmanik D. L. , Demekhov A. G.
Published: July 2017

We study specific features of VLF waves propagation in the Earth's ionosphere and magnetosphere in the presence of large‐scale field‐aligned plasma inhomogeneities (ducts). These inhomogeneities can, e.g., be formed during the ionosphere heating by high‐power HF facilities such as High Frequency Active Auroral Research Program and “Sura.” They can extend up to altitudes of several thousand kilometers along geomagnetic field lines and have transverse scales of about 1° determined by the heated region scale. We analyze ray trajectories of VLF waves with frequencies of 1 to 15 kHz starting from about 100 km altitude and use the plasma parameters obtained within the framework of the SAMI2 simulation model (Huba et al., 2000). This model employs MHD equations for thermal plasma and allows one to obtain the plasma parameters along the entire magnetic flux tube in a fixed meridional plane. By knowing the ray trajectories, we calculate and compare the amplitude variation along the ray paths for the cases of unperturbed and heated ionosphere. We show that the presence of a large‐scale density disturbance produced by the HF heating can lead to significant changes of wave propagation trajectories. In particular, efficient guiding of VLF waves in this region can take place, which in turn can result in the appearance of several wave focusing regions and a drastic local increase of the VLF wave amplitude in these regions (up to ∼10 times as compared to the case of unperturbed plasma). The number of focusing regions is determined by an extension of an artificial duct along the geomagnetic field.
Ionospheric electron heating associated with pulsating auroras: A Swarm survey and model simulation
Authors: Liang Jun , Yang B. , Donovan E. , Burchill J. , Knudsen D.
Published: July 2017

In this paper we report a study on the plasma signatures (electron temperature, plasma density, and field‐aligned current) of patchy pulsating auroras in the upper F region ionosphere using Swarm satellite data. Via a survey of 38 patch crossing events, we repeatedly identify a strong electron temperature enhancement associated with the pulsating aurora. On average, the electron temperature at Swarm satellite altitudes (~460 km) increases from ~2200 K at subauroral latitudes to a peak of ~3000 K within the pulsating auroral patch. This indicates that pulsating auroras may act as an important heating source for the nightside ionosphere. On the other hand, no well‐defined trend of plasma density variations associated with pulsating auroras is identified at Swarm altitudes. The field‐aligned currents within the pulsating aurora patch are mostly upward, with mean magnitudes on order of ~1 μA/m2. We then perform a numerical simulation to explore the potential mechanisms underlying the strong electron heating associated with the pulsating aurora. Via simulations we find that to account for the realistic electron temperature observation in a major portion of our events, pulsating auroras are likely accompanied by substantial magnetospheric heat fluxes around the order of ~1010 eV/cm2. We propose that such magnetospheric heat fluxes may be pertinent to one long‐hypothesized feature of pulsating auroras, namely, the coexistence of an enhanced low‐energy plasma population in magnetic flux tubes threading the pulsating aurora, in addition to the energetic electron precipitation. Via a Swarm survey we repeatedly find a strong electron temperature enhancement associated with the pulsating aurora The field‐aligned currents within pulsating auroras are moderately upward, with mean magnitudes on the order of ~1e−6 A/m2 To explain the observed electron heating, pulsating auroras are likely accompanied by magnetospheric heat fluxes around ~1E+10 eV/cm2/s.
Flux ropes in the Hermean magnetotail: Distribution, properties, and formation
Authors: Smith A. W. , Slavin J. A. , Jackman C. M. , Poh G.‐K. , Fear R. C.
Published: July 2017

An automated method was applied to identify magnetotail flux rope encounters in MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) magnetometer data. The method identified significant deflections of the north‐south component of the magnetic field coincident with enhancements in the total field or dawn‐dusk component. Two hundred forty‐eight flux ropes are identified that possess well‐defined minimum variance analysis (MVA) coordinate systems, with clear rotations of the field. Approximately 30% can be well approximated by the cylindrically symmetric, linearly force‐free model. Flux ropes are most common moving planetward, in the postmidnight sector. Observations are intermittent, with the majority (61%) of plasma sheet passages yielding no flux ropes; however, the peak rate of flux ropes during a reconnection episode is ∼5 min−1. Overall, the peak postmidnight rate is ∼0.25 min−1. Only 25% of flux ropes are observed in isolation. The radius of flux ropes is comparable to the ion inertial length within Mercury's magnetotail plasma sheet. No clear statistical separation is observed between tailward and planetward moving flux ropes, suggesting the near‐Mercury neutral line (NMNL) is highly variable. Flux ropes are more likely to be observed if the preceding lobe field is enhanced over background levels. A very weak correlation is observed between the flux rope core field and the preceding lobe field orientation; a stronger relationship is found with the orientation of the field within the plasma sheet. The core field strength measured is ∼6 times stronger than the local dawn‐dusk plasma sheet magnetic field.
Climatology of semidiurnal lunar and solar tides at middle and high latitudes: Interhemispheric comparison
Authors: Conte J. Federico , Chau Jorge L. , Stober Gunter , Pedatella Nicholas , Maute Astrid , Hoffmann Peter , Janches Diego , Fritts David , Murphy Damian J.
Published: July 2017

The semidiurnal lunar and solar tides obtained from meteor radar measurements spanning from 2009 to 2013 observed at Davis (69°S) and Rio Grande (54°S) are presented and compared to the Northern Hemisphere ones at Andenes (69°N) and Juliusruh (54°N). Mean tidal differences for both intrahemispheric and interhemispheric scenarios are analyzed. Tidal behavior is also compared against numerical simulations during 2009 and 2013 sudden stratospheric warming (SSW) time periods. Possible influences in the Southern Hemisphere from the local stratosphere are also investigated using Modern Era Retrospective analysis for Research and Applications, version 2 (MERRA 2) data sets. The main features of the mean zonal wind are similar in both hemispheres, i.e., stronger amplitudes over midlatitude locations, eastward winds during winter and westward below 90 km with eastward higher up during corresponding summer times. On the other hand, the semidiurnal solar tides observed in the Southern Hemisphere show clear differences when compared to the Northern Hemisphere and between middle‐ and high‐latitude locations at the same hemisphere. These differences are even larger for the semidiurnal lunar tide, which shows stronger amplitudes from October to March and March to October, over Davis and Rio Grande, respectively. Our results indicate that the lunar tides over the Southern Hemisphere midlatitudes are more prone to react to the Northern Hemisphere stratospheric polar vortex influences, in agreement with numerical simulations, particularly for the time of the 2013 SSW.
Characterizing the information content of cloud thermodynamic phase retrievals from the notional PACE OCI shortwave reflectance measurements
Authors: Coddington O. M. , Vukicevic T. , Schmidt K. S. , Platnick S.
Published: July 2017

We rigorously quantify the probability of liquid or ice thermodynamic phase using only shortwave spectral channels specific to the National Aeronautics and Space Administration's Moderate Resolution Imaging Spectroradiometer, Visible Infrared Imaging Radiometer Suite, and the notional future Plankton, Aerosol, Cloud, ocean Ecosystem imager. The results show that two shortwave‐infrared channels (2135 and 2250 nm) provide more information on cloud thermodynamic phase than either channel alone; in one case, the probability of ice phase retrieval increases from 65 to 82% by combining 2135 and 2250 nm channels. The analysis is performed with a nonlinear statistical estimation approach, the GEneralized Nonlinear Retrieval Analysis (GENRA). The GENRA technique has previously been used to quantify the retrieval of cloud optical properties from passive shortwave observations, for an assumed thermodynamic phase. Here we present the methodology needed to extend the utility of GENRA to a binary thermodynamic phase space (i.e., liquid or ice). We apply formal information content metrics to quantify our results; two of these (mutual and conditional information) have not previously been used in the field of cloud studies.
An influence of extreme southern hemisphere cold surges on the North Atlantic Subtropical High through a shallow atmospheric circulation
Authors: Bowerman A. R. , Fu R. , Yin L. , Fernando D. N. , Arias P. A. , Dickinson R. E.
Published: July 2017

Previous studies have attributed interhemisphere influences of the atmosphere to the latitudinal propagation of planetary waves crossing the equator, to the triggering of equatorial Kelvin waves, or to monsoonal circulation. Over the American‐Atlantic sector, such cross‐equatorial influences rarely occur during boreal summer due to unfavorable atmospheric conditions. We have observed that an alternative mechanism provides an interhemisphere influence. When episodes of extreme cold surges and upper tropospheric westerly winds occur concurrently over southern hemisphere Amazonia, cold surges from extratropical South America can penetrate deep into southern Amazonia. Although they do not appear to influence upper tropospheric circulation of the northern hemisphere, extremely strong southerly cross‐equatorial advection (>2σ standard deviations, or 2) of cold and dense air in the lower troposphere can reach as least 10°N. Such cold advection increases the northward cross‐equatorial pressure gradient in the lower to middle troposphere, thus shallow northerly return flow below 500 hPa. This return flow and the strong lower tropospheric southerly cross‐equatorial flow form an anomalous shallow meridional circulation spanning from southern Amazonia to the subtropical North Atlantic, with increased geopotential height anomalies exceeding +1σ to at least 18°N. It projects onto the southern edge of the North Atlantic Subtropical High (NASH), increasing its pressure and leading to equatorward expansion of NASH's southern boundary. These anomalies enhance the NASH, leading to its equatorward expansion. These extreme cold surges can potentially improving the predictability of weather patterns of the tropical and subtropical Atlantic, including the variability of the NASH's southern edge.
Evaluation of NASA Deep Blue/SOAR aerosol retrieval algorithms applied to AVHRR measurements
Authors: Sayer A. M. , Hsu N. C. , Lee J. , Carletta N. , Chen S.‐H. , Smirnov A.
Published: July 2017

The Deep Blue (DB) and Satellite Ocean Aerosol Retrieval (SOAR) algorithms have previously been applied to observations from sensors like the Moderate Resolution Imaging Spectroradiometers (MODIS) and Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS) to provide records of midvisible aerosol optical depth (AOD) and related quantities over land and ocean surfaces, respectively. Recently, DB and SOAR have also been applied to Advanced Very High Resolution Radiometer (AVHRR) observations from several platforms (NOAA11, NOAA14, and NOAA18), to demonstrate the potential for extending the DB and SOAR AOD records. This study provides an evaluation of the initial version (V001) of the resulting AVHRR‐based AOD data set, including validation against Aerosol Robotic Network (AERONET) and ship‐borne observations, and comparison against both other AVHRR AOD records and MODIS/SeaWiFS products at select long‐term AERONET sites. Although it is difficult to distil error characteristics into a simple expression, the results suggest that one standard deviation confidence intervals on retrieved AOD of ±(0.03 + 15%) over water and ±(0.05 + 25%) over land represent the typical level of uncertainty, with a tendency toward negative biases in high‐AOD conditions, caused by a combination of algorithmic assumptions and sensor calibration issues. Most of the available validation data are for NOAA18 AVHRR, although performance appears to be similar for the NOAA11 and NOAA14 sensors as well.
Laser‐Induced Localized Growth of Methylammonium Lead Halide Perovskite Nano‐ and Microcrystals on Substrates
Authors: Arciniegas Milena P. , Castelli Andrea , Piazza Simonluca , Dogan Sedat , Ceseracciu Luca , Krahne Roman , Duocastella Marti , Manna Liberato
Published: July 2017

Perovskite‐based optoelectronic devices have shown remarkable performances, especially in the field of photovoltaics. Still, a rapid solution‐processing approach able to produce localized stable perovskite crystals remains a general challenge, and is a key step toward the miniaturization of such materials in on‐chip components. This study presents the confined growth of methylammonium (MA) lead halide perovskite crystals that is thermally induced through localized laser irradiation. Importantly, such structures remain stable over time; that is, they neither dissolve back into the surrounding liquid nor detach from the substrate. This is attributed to a chemical reaction locally triggered by the induced heat on the substrate surface that is transferred to the perovskite precursors (liquid) layer, thus generating “on‐demand” MA ions from the N‐methylformamide solvent. By tuning the laser parameters, such as power density or irradiation time, variations in shape and size of the crystals, from microcrystals of ≈50 µm to nanocuboids of ≈500 nm, are observed. This study also demonstrates that with an optimized distance between the irradiated regions and by controlling the relative laser displacement speed, luminescent and photoconductive MAPbBr3 wires and microplates can be generated.