bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulation of Immune Responses by Exosomes Derived from Antigen-Presenting Cells
Authors: Shenoda Botros B. , Ajit Seena K.
Published: September 2016

Exosome-mediated signaling is important in mediating the inflammatory response. To exert their biological or pathophysiological functions in the recipient cells, exosomes deliver a diverse array of biomacromolecules including long and short coding and non-coding RNAs, proteins, and lipids. Exosomes secreted by antigen-presenting cells can confer therapeutic benefits by attenuating or stimulating the immune response. Exosomes play a crucial role in carrying and presenting functional major histocompatibility peptide complexes to modulate antigen-specific T cell responses. Exosomes from Dendritic Cells (DCs) can activate T and B cells and have been explored for their immunostimulatory properties in cancer therapy. The immunosuppressive properties of exosomes derived from macrophages and DCs can reduce inflammation in animal models for several inflammatory disorders. This review focuses on the protective role of exosomes in attenuating inflammation or augmenting immune response, emphasizing studies on exosomes derived from DCs and macrophages.
Article Commentary: Archival Collections are Important in the Study of the Biology, Diversity, and Evolution of Arboviruses
Authors: Pyke Alyssa T. , Warrilow David
Published: September 2016

Historically, classifications of arboviruses were based on serological techniques. Hence, collections of arbovirus isolates have been central to this process by providing the antigenic reagents for these methods. However, with increasing concern about biosafety and security, the introduction of molecular biology techniques has led to greater emphasis on the storage of nucleic acid sequence data over the maintenance of archival material. In this commentary, we provide examples of where archival collections provide an important source of genetic material to assist in confirming the authenticity of reference strains and vaccine stocks, to clarify taxonomic relationships particularly when isolates of the same virus species have been collected across a wide expanse of time and space, for future phenotypic analysis, to determine the historical diversity of strains, and to understand the mechanisms leading to changes in genome structure and virus evolution.
The phase transition in random regular exact cover
Authors: Moore Cristopher
Published: September 2016

A

k

-uniform,

d

-regular instance of EXACT COVER is a family of

m

sets

F_{n,d,k} = \{ S_j \subseteq \{1,\ldots,n\} \}

, where each subset has size

k

and each

1 \le i \le n

is contained in

d

of the

S_j

. It is satisfiable if there is a subset

T \subseteq \{1,\ldots,n\}

such that

|T \cap S_j|=1

for all

j

. Alternately, we can consider it a

d

-regular instance of POSITIVE 1-IN-

k

SAT, i.e., a Boolean formula with

m

clauses and

n

variables where each clause contains

k

variables and demands that exactly one of them is true. We determine the satisfiability threshold for random instances of this type with

k > 2

. Letting

d^\star = \frac{\ln k}{(k-1)(- \ln (1-1/k))} + 1 \, ,

we show that

F_{n,d,k}

is satisfiable with high probability if

d < d^\star

and unsatisfiable with high probability if

d > d^\star

. We do this with a simple application of the first and second moment methods, boosting the probability of satisfiability below

d^\star

to

1-o(1)

using the small subgraph conditioning method.
Validation and update of OMI Total Column Water Vapor product
Authors: Wang Huiqun , Gonzalez Abad Gonzalo , Liu Xiong , Chance Kelly
Published: September 2016

Abstract. The collection 3 Ozone Monitoring Instrument (OMI) Total Column Water Vapor (TCWV) data generated by the Smithsonian Astrophysical Observatory's (SAO) algorithm version 1.0 and archived at the Aura Validation Data Center (AVDC) are compared with NCAR's ground-based GPS data, AERONET's sun-photometer data, and Remote Sensing System's (RSS) SSMIS data. Results show that the OMI data track the seasonal and interannual variability of TCWV for a wide range of climate regimes. During the period from 2005 to 2009, the mean OMI−GPS over land is −0.3 mm and the mean OMI−AERONET over land is 0 mm. For July 2005, the mean OMI−SSMIS over the ocean is −4.3 mm. The better agreement over land than over the ocean is corroborated by the smaller fitting residuals over land and suggests that liquid water is a key factor for the fitting quality over the ocean in the version 1.0 retrieval algorithm. We find that the influence of liquid water is reduced using a shorter optimized retrieval window of 427.7–465 nm. As a result, the TCWV retrieved with the new algorithm increases significantly over the ocean and only slightly over land. We have also made several updates to the air mass factor (AMF) calculation. The updated version 2.1 retrieval algorithm improves the land/ocean consistency and the overall quality of the OMI TCWV data set. The version 2.1 OMI data largely eliminate the low bias of the version 1.0 OMI data over the ocean and are 1.5 mm higher than RSS's “clear” sky SSMIS data in July 2005. Over the ocean, the mean of version 2.1 OMI−GlobVapour is 1 mm for July 2005 and 0 mm for January 2005. Over land, the version 2.1 OMI data are about 1 mm higher than GlobVapour when TCWV  <  15 mm and about 1 mm lower when TCWV  >  15 mm.
Sea-ice indicators of polar bear habitat
Authors: Stern Harry L. , Laidre Kristin L.
Published: September 2016

Abstract. Nineteen subpopulations of polar bears (Ursus maritimus) are found throughout the circumpolar Arctic, and in all regions they depend on sea ice as a platform for traveling, hunting, and breeding. Therefore polar bear phenology – the cycle of biological events – is linked to the timing of sea-ice retreat in spring and advance in fall. We analyzed the dates of sea-ice retreat and advance in all 19 polar bear subpopulation regions from 1979 to 2014, using daily sea-ice concentration data from satellite passive microwave instruments. We define the dates of sea-ice retreat and advance in a region as the dates when the area of sea ice drops below a certain threshold (retreat) on its way to the summer minimum or rises above the threshold (advance) on its way to the winter maximum. The threshold is chosen to be halfway between the historical (1979–2014) mean September and mean March sea-ice areas. In all 19 regions there is a trend toward earlier sea-ice retreat and later sea-ice advance. Trends generally range from −3 to −9 days decade−1 in spring and from +3 to +9 days decade−1 in fall, with larger trends in the Barents Sea and central Arctic Basin. The trends are not sensitive to the threshold. We also calculated the number of days per year that the sea-ice area exceeded the threshold (termed ice-covered days) and the average sea-ice concentration from 1 June through 31 October. The number of ice-covered days is declining in all regions at the rate of −7 to −19 days decade−1, with larger trends in the Barents Sea and central Arctic Basin. The June–October sea-ice concentration is declining in all regions at rates ranging from −1 to −9 percent decade−1. These sea-ice metrics (or indicators of habitat change) were designed to be useful for management agencies and for comparative purposes among subpopulations. We recommend that the National Climate Assessment include the timing of sea-ice retreat and advance in future reports.
Giant Endometrioma of the Ovary: A Case Report
Authors: Mishra Tushar Subhadarshan , Singh Sweta , Jena Saubhagya Kumar , Mishra Pritinanda , Mishra Lipsa
Published: September 2016

Endometriosis is a common gynaecological condition, affecting between 6%-10% of women in the reproductive age group. Ovarian endometrioma is seen in approximately 17%-44% of women with endometriosis. While the ovaries remain the commonest site of endometriosis, the size of ovarian endometriomas is typically not large, usually ranging from 1-6 cm. Huge ovarian endometriomas are extremely rare, with only a few case reports being described. We report a case of giant ovarian endometrioma in a 38-year-old multiparous woman, and discuss the challenges in diagnosis and management.
CHIRONOMIDS AND THEIR BUCCAL DEFORMITIES FOUND IN MAGDALENA RIVER CATCHMENT (COLOMBIA) AND THE DELICACY OF SPATIAL SCALES IN THE TROPICS
Authors: Riss H.W. , Nazarova L.B. , Ospina T. R.
Published: September 2016

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New combinations of Afrotropical Chironomini (Diptera: Chironomidae)
Authors: Ekrem Torbjørn , Stur Elisabeth
Published: September 2016

During our work on the Chironomidae chapter of the forthcoming Manual of Afrotropical Diptera we examined type material of the four Chironomini species Chironomus (Endochironomus) hamatus, Chironomus (E.) pruinosus, Chironomus (E.) woodi and Chironomus (Cryptochironomus) inflexus described by Paul Freeman. We provide photos of the types and associated material and argue for the following generic placements: Chironomus (Benthalia) hamatus comb.n., Kiefferulus pruinosus comb. n., Synendotendipes woodi comb. n. and Cladopelma inflexum.
Análise da influência da taxa de aprendizado e do fator de desconto sobre o desempenho dos algoritmos Q-learning e SARSA: aplicação do aprendizado por reforço na navegação autônoma
Authors: Ottoni André Luiz Carvalho , Nepomuceno Erivelton Geraldo , Oliveira Marcos Santos de , Cordeiro Lara Toledo , Lamperti Rubisson Duarte
Published: September 2016

Nos algoritmos de aprendizado por reforço, a taxa de aprendizado (alpha) e o fator de desconto (gamma) podem ser definidos entre qualquer valor no intervalo entre 0 e 1. Assim, adotando os conceitos de regressão logística, é proposta uma metodologia estatística para a análise da influência da variação de \alpha e \gamma nos algoritmos Q-learning e SARSA. Como estudo de caso, o aprendizado por reforço foi aplicado em experimentos de navegação autônoma. A análise de resultados mostrou que simples variações em \alpha e \gamma podem interferir diretamente no desempenho do aprendizado por reforço.
Editorial
Authors: Hölbig Carlos Amaral
Published: September 2016

Apresentação do décimo sexto número da Revista Brasileira de Computação Aplicada por parte do editor da revista.
Developing a Model for Promoting Professional Ethics of Faculty Members at the Islamic Azad University in the Dimension of Education
Authors: Taheri Leila Mir , Maleki Hamid
Published: September 2016

The current research aimed to develop a model for promoting professional ethics of faculty members of the Islamic Azad University. For this, the most important components and areas of professional ethics were identified; also, relationship between professional ethics and some demographic characteristics, including gender, age and educational major were addressed. To meet this goal, a sample of education practitioners, faculty members and doctoral students was selected via a purposive sampling method for the qualitative part of the research. Also, via studying documents and interviews conducted with the academic practitioners and doctoral students, professional ethics related components were identified, and accordingly, an inventory consisting of 81 items was prepared and was administered to 600 faculty members of Azad University. Factorial analysis results indicated that the individual area consisted of 4 components, which explained 78/53% of its variance in total; organizational area consisted of 3 components which explained 68/96% of its variance and one factor was obtained within the environmental area that explained 86/82% of its variance. Results of structural equations modeling suggested that the recommended conceptual model enjoyed some acceptable goodness of fit with data. Findings pertaining to the validation of the model, including five parts (philosophy and objectives, theoretical basics, perception framework, administrative stages and evaluation system) illustrated that the model enjoys good validity from the views of experts.
Design and Implementation of Pulse Width Modulation Driving System for Voice Coil Motor
Authors: Liu Rilong , Liu Renxin
Published: September 2016

According to the performance requirements of the control system for voice coil motor, a pulse width modulation driving system is designed and implemented based on an integrated power device and a field programmable gate array. LMD18200 is used as the motor driver to design the unit of switch type power driving. With APA300 as the digital controller, the modular design of the digital controller realizes with the Verilog hardware describing language, so it has a good flexibility and portability. The experimental results show that the current loop can rapidly keep track of current changes under the working condition of the voice coil motor power driver. Therefore, the servo system of voice coil motor is compared with the practical requirement.
Size-dependent changeover in magnetization reversal mode of self-assembled one-dimensional chains of spherical Fe3O4 nanoparticles
Authors: Samardak Alexander S. , Davydenko Alexander V. , Ognev Alexey V. , Jeon Yoo Sang , Choi Young Soo , Kim Young Keun
Published: September 2016

Understanding the ferromagnetic behavior of coupled magnetic nanoparticles (NPs) in a chain structure, called a “nanochain (NC)”, will open up new routes for its practical use. Here, we report the magnetization reversal modes in isolated magnetite (Fe3O4) NPs with diameters of 100 and 200 nm, as well as those of one-dimensional (1D) self-assembled NCs consisting of these NPs. NCs consisting of 100-nm diameter NPs switched through a transverse domain wall-like motion. Meanwhile, in 200-nm diameter NPs and NCs, we observed 3D magnetic vortex states that were more energetically favorable than single domain or multidomain states.
Degradation of encapsulants for photovoltaic modules made of ethylene vinyl acetate studied by positron annihilation lifetime spectroscopy
Authors: Hagihara Hideaki , Kunioka Masao , Suda Hiroyuki , Hara Yukiko , Masuda Atsushi
Published: September 2016

The structure of ethylene vinyl acetate (EVA) encapsulants of crystalline-Si photovoltaic modules after the damp heat (DH) test was evaluated by positron annihilation lifetime spectroscopy (PALS). A reduction in free-volume hole size, which indicates the progress of deacetylation, was observed after the DH test. The difference in lifetime (Δτ) between the initial and DH-tested samples clearly increased after the DH test for 3000 h. The increase in Δτ was correlated with the acetic acid concentration in the EVA estimated by ion chromatography. The depth profile analysis by slow positron beam PALS revealed that Δτ in the near-surface region of the Si-cell side was significantly larger than that of the cover-glass side. This result indicates that deacetylation near the Si cell/EVA interface is accelerated.
Assessoria Aberta com Viés Social: Um Estudo de Caso no Centro de Referência de Assistência Social
Authors: Ramos Suéllen , Kotzko Ana Maria , Gonçalves Eloyse , Nonato Junior Raimundo
Published: September 2016

O presente estudo teve por objetivo realizar uma análise sobre o Centro de Referência de Assistência Social (CRAS). O estudo transcorre a estrutura organizacional do CRAS e a política de assistência social na forma de proteção social básica, articulando como meio de mediação, da gestão-sociedade às assessorias abertas. Utilizou-se o método dialético para reconhecer a realidade e transpô-la como conhecimento de forma exploratória e descritiva, no contexto da abordagem qualitativa, empregando-se as técnicas de tipo de pesquisa bibliográfica, documental e entrevista. Os resultados obtidos apontam para três principais categorias: serviços, gestão do CRAS e gestão das assessorias abertas. Os diálogos entre a gestão social e o Secretariado Executivo se apresenta interdisciplinar de forma a preencher as lacunas que emergem ao se revelar a problemática existente no Centro de Referência de Assistência Social sob a perspectiva de que a sua gestão pode ser analisada através das assessorias abertas, com o objetivo de mostrar a articulação gestão-sociedade do CRAS sob a óptica dos conhecimentos transversais na área das assessorias.
O Secretário Executivo Bilíngue como Agente Facilitador em Negociações do Mercosul
Authors: Nascimento Helton Ferreira , Da Silva Karla Janaina Alexandre
Published: September 2016

O presente trabalho se volta ao fenômeno da globalização e sua contribuição para a formação de blocos econômicos, como o Mercado Comum do Sul (MERCOSUL). Nesse contexto, ressalta-se a importância da língua espanhola para as negociações comerciais do Brasil com os demais países membros, como o objetivo enfatizar a participação do profissional de Secretariado Executivo Bilíngue (SEB) e sua possibilidade de atuação nesse contexto. A metodologia de pesquisa utilizada é a dedutivo-explicativa, procurando identificar quais foram os fatores determinantes na sua elaboração, sendo embasada a partir de livros e sites relacionados ao tema, caracterizada ainda como bibliográfica. Tais aspectos possibilitaram a construção da reflexão de que com as mudanças na economia mundial e a criação de blocos como o MERCOSUL, as empresas que atuam no Brasil necessitam de profissionais que atendam as exigências desse mercado. Por isso, o profissional de SEB está apto para atuar como agente facilitador em negociações do MERCOSUL.
Urban lifecycle management: A research program for smart government of smart cities
Authors: Rochet Claude , Correa Juan David Pinzón
Published: September 2016

At date, there is no standardized definition of what a smart city is, in spite many apply to propose a definition that fit with their offer, subsuming the whole of the city in one of its functions (smart grid, smart mobility…). Considering the smart cities as an ecosystem, that is to say a city that has systemic auto poeitic properties that are more than the sum of its parts, we develop an approach of modeling the smartness of the city. To understand how the city may behave as a sustainable ecosystem, we need a framework to design the interactions of the city subsystems. First we define a smart city as an ecosystem that is more than the sum of its parts, where sustainability is maintained through the interactions of urban functions. Second, we present a methodology to sustain the development over time of this ecosystem: Urban Lifecycle Management. Third, we define the tasks to be carried out by an integrator of the functions that constitute the smart city, we assume public administration has to play this role. Fourth, we present what should be a smart government for the smart city and the new capabilities to be developed.
Gestão Sustentável do Turismo: Proposição de Protocolo de Práticas e Processos de Implementação de Responsabilidade Social Corporativa para os meios de hospedagem da Grande Florianópolis
Authors: Welzel Evelize , Brazil Julia Lorenzatto
Published: September 2016

O objetivo deste estudo é mapear padrões e normas de turismo sustentável e contrapô-las às boas práticas de RSC definidas no Framework de RSC, de modo a propor um protocolo de práticas e instrumentos para desenvolvimento e implementação de estratégias socialmente responsáveis para o segmento de meios de hospedagem na região da Grande Florianópolis. Destarte, contextualizou-se a relevância da RSC para o segmento ora estudado. A seguir, apresenta-se os pilares constitutivos da RSC e discute-se seu processo de implementação estratégica na esfera organizacional. Complementarmente, aborda-se o papel da RSC diante dos desafios da gestão sustentável do segmento estudado. Trata-se, portanto, de um trabalho essencialmente teórico, que procura responder ‘quais são as atividades de RSC que podem ser caracterizadas como `melhores práticas’ e os instrumentos de RSC para introdução, em termos estratégicos, na estrutura organizacional do segmento de meios de hospedagem?’. Para tanto, identificou-se duas certificações relacionadas ao turismo sustentável, o Green Globe e a NIH-54:2004. Em seguida, realizou-se uma análise equiparativa, tendo como sustentação principal o Framework de RSC. Resultante dessa análise emerge o protocolo de práticas e instrumentos para desenvolvimento e implementação de estratégias socialmente responsáveis para o segmento estudado. Destaca-se que a pesquisa contribuiu na ampliação do Framework de RSC, de 30 para 48 statements concernentes às práticas, bem como de 26 para 35 statements relativos às fases gerais de implementação de RSC, totalizando, respectivamente, um acréscimo de 18 e 9 statements ao modelo.
Mitigation of methane emissions in cities: How new measurements and partnerships can contribute to emissions reduction strategies
Authors: Hopkins Francesca M. , Ehleringer James R. , Bush Susan E. , Duren Riley M. , Miller Charles E. , Lai Chun‐Ta , Hsu Ying‐Kuang , Carranza Valerie , Randerson James T.
Published: September 2016

Cities generate 70% of anthropogenic greenhouse gas emissions, a fraction that is growing with global urbanization. While cities play an important role in climate change mitigation, there has been little focus on reducing urban methane (CH4) emissions. Here, we develop a conceptual framework for CH4 mitigation in cities by describing emission processes, the role of measurements, and a need for new institutional partnerships. Urban CH4 emissions are likely to grow with expanding use of natural gas and organic waste disposal systems in growing population centers; however, we currently lack the ability to quantify this increase. We also lack systematic knowledge of the relative contribution of these distinct source sectors on emissions. We present new observations from four North American cities to demonstrate that CH4 emissions vary in magnitude and sector from city to city and hence require different mitigation strategies. Detections of fugitive emissions from these systems suggest that current mitigation approaches are absent or ineffective. These findings illustrate that tackling urban CH4 emissions will require research efforts to identify mitigation targets, develop and implement new mitigation strategies, and monitor atmospheric CH4 levels to ensure the success of mitigation efforts. This research will require a variety of techniques to achieve these objectives and should be deployed in cities globally. We suggest that metropolitan scale partnerships may effectively coordinate systematic measurements and actions focused on emission reduction goals.
Lithium isotopic systematics of submarine vent fluids from arc and back‐arc hydrothermal systems in the western Pacific
Authors: Araoka Daisuke , Nishio Yoshiro , Gamo Toshitaka , Yamaoka Kyoko , Kawahata Hodaka
Published: September 2016

The Li concentration and isotopic composition (δ7Li) in submarine vent fluids are important for oceanic Li budget and potentially useful for investigating hydrothermal systems deep under the seafloor because hydrothermal vent fluids are highly enriched in Li relative to seawater. Although Li isotopic geochemistry has been studied at mid‐ocean‐ridge (MOR) hydrothermal sites, in arc and back‐arc settings Li isotopic composition has not been systematically investigated. Here we determined the δ7Li and 87Sr/86Sr values of 11 end‐member fluids from 5 arc and back‐arc hydrothermal systems in the western Pacific and examined Li behavior during high‐temperature water‐rock interactions in different geological settings. In sediment‐starved hydrothermal systems (Manus Basin, Izu‐Bonin Arc, Mariana Trough, and North Fiji Basin), the Li concentrations (0.23–1.30 mmol/kg) and δ7Li values (+4.3‰ to +7.2‰) of the end‐member fluids are explained mainly by dissolution‐precipitation model during high‐temperature seawater‐rock interactions at steady state. Low Li concentrations are attributable to temperature‐related apportioning of Li in rock into the fluid phase and phase separation process. Small variation in Li among MOR sites is probably caused by low‐temperature alteration process by diffusive hydrothermal fluids under the seafloor. In contrast, the highest Li concentrations (3.40–5.98 mmol/kg) and lowest δ7Li values (+1.6‰ to +2.4‰) of end‐member fluids from the Okinawa Trough demonstrate that the Li is predominantly derived from marine sediments. The variation of Li in sediment‐hosted sites can be explained by the differences in degree of hydrothermal fluid‐sediment interactions associated with the thickness of the marine sediment overlying these hydrothermal sites.
Dependence of seismic coupling on normal fault style along the Northern Mid‐Atlantic Ridge
Authors: Olive Jean‐Arthur , Escartín Javier
Published: September 2016

While normal faults are essential in shaping the seafloor formed at slow spreading mid‐ocean ridges, information on their behavior on short (seismic cycle) time scales is limited. Here we combine catalogs of hydro‐acoustically and teleseismically recorded earthquakes to characterize the state of seismic coupling along the Northern Mid‐Atlantic Ridge (MAR) between 12°N and 35°N. Along this portion of the MAR axis, tectonic extension is either taken up by steep conjugate faults that outline well‐defined ridge‐parallel abyssal hills, or dominantly by a large‐offset detachment fault on one side of the axis. We investigate variations in seismicity and seismic moment release rates across 30 ridge sections that can be clearly characterized either as abyssal hill or detachment bearing. We find that detachment‐bearing sections are associated with significantly greater seismicity and moment release rates than abyssal hill‐bearing sections but show variability that may reflect the along‐axis extent of individual detachment faults. Overall, the measured seismic moment release rates fail to account for the long‐term fault slip rates. This apparent seismic deficit could indicate a mixed‐mode of fault slip where earthquakes only account for ∼10–30% of offset buildup at abyssal hill faults, while the rest is accommodated by some form of transient aseismic creep. We find this seismic coupling fraction to be significantly greater (∼40–60%) at individual detachment systems, which is somewhat at odds with the common inference that detachment faults can sustain long‐lived localized strain because they are weak. We therefore propose alternative interpretations for seismic coupling based on dynamic friction theory.
High atmospheric demand for water can limit forest carbon uptake and transpiration as severely as dry soil
Authors: Sulman Benjamin N. , Roman D. Tyler , Yi Koong , Wang Lixin , Phillips Richard P. , Novick Kimberly A.
Published: September 2016

When stressed by low soil water content (SWC) or high vapor pressure deficit (VPD), plants close stomata, reducing transpiration and photosynthesis. However, it has historically been difficult to disentangle the magnitudes of VPD compared to SWC limitations on ecosystem‐scale fluxes. We used a 13 year record of eddy covariance measurements from a forest in south central Indiana, USA, to quantify how transpiration and photosynthesis respond to fluctuations in VPD versus SWC. High VPD and low SWC both explained reductions in photosynthesis relative to its long‐term mean, as well as reductions in transpiration relative to potential transpiration estimated with the Penman‐Monteith equation. Flux responses to typical fluctuations in SWC and VPD had similar magnitudes. Integrated over the year, VPD fluctuations accounted for significant reductions of GPP in both nondrought and drought years. Our results suggest that increasing VPD under climatic warming could reduce forest CO2 uptake regardless of changes in SWC.
An initial assessment of SMAP soil moisture retrievals using high‐resolution model simulations and in situ observations
Authors: Pan Ming , Cai Xitian , Chaney Nathaniel W. , Entekhabi Dara , Wood Eric F.
Published: September 2016

At the end of its first year of operation, we compare soil moisture retrievals from the Soil Moisture Active Passive (SMAP) mission to simulations from a land surface model with meteorological forcing downscaled from observations/reanalysis and in situ observations from sparse monitoring networks within continental United States (CONUS). The radar failure limits the duration of comparisons for the active and combined products (~3 months). Nevertheless, the passive product compares very well against in situ observations over CONUS. On average, SMAP compares to the in situ data even better than the land surface model and provides significant added value on top of the model and thus good potential for data assimilation. At large scale, SMAP is in good agreement with the model in most of CONUS with less‐than‐expected degradation over mountainous areas. Lower correlation between SMAP and the model is seen in the forested east CONUS and significantly lower over the Canadian boreal forests.
The effect of atmospheric sulfate reductions on diffuse radiation and photosynthesis in the United States during 1995–2013
Authors: Keppel‐Aleks G. , Washenfelder R. A.
Published: September 2016

Aerosol optical depth (AOD) has been shown to influence the global carbon sink by increasing the fraction of diffuse light, which increases photosynthesis over a greater fraction of the vegetated canopy. Between 1995 and 2013, U.S. SO2 emissions declined by over 70%, coinciding with observed AOD reductions of 3.0 ± 0.6% yr−1 over the eastern U.S. In the Community Earth System Model (CESM), these trends cause diffuse light to decrease regionally by almost 0.6% yr−1, leading to declines in gross primary production (GPP) of 0.07% yr−1. Integrated over the analysis period and domain, this represents 0.5 Pg C of omitted GPP. A separate upscaling calculation that used published relationships between GPP and diffuse light agreed with the CESM model results within 20%. The agreement between simulated and data‐constrained upscaling results strongly suggests that anthropogenic sulfate trends have a small impact on carbon uptake in temperate forests due to scattered light.
Comparisons of observed and modeled elastic responses to hydrological loading in the Amazon basin
Authors: Moreira D. M. , Calmant S. , Perosanz F. , Xavier L. , Rotunno Filho O. C. , Seyler F. , Monteiro A. C.
Published: September 2016

In large hydrological basins, water mass loading can produce significant crustal deformation. We compare the monthly vertical component of 18 GPS sites located in the Amazon basin, with the deflection models derived from Gravity Recovery and Climate Experiment (GRACE) observations on the one hand and derived from HYDL, a global hydrological model, on the other hand. The GPS data set includes the largest deflections by hydrological loading ever recorded at two stations located in the center of the basin. The main result of the study is that the GRACE solution produced by GRGS (Groupe de Recherche en Géodesie Spatiale, Toulouse, France) produces the best agreement with the Global Navigation Satellite Systems series with a correlation coefficient up to 0.9 in the center of the basin, although 70% at best of the RMS variation in the GPS series is accounted for.
Relocation of long‐period (LP) seismic events reveals en echelon fractures in the upper edifice of Turrialba volcano, Costa Rica
Authors: Zecevic Megan , De Barros Louis , Eyre Thomas S. , Lokmer Ivan , Bean Christopher J.
Published: September 2016

Swarms of long‐period (LP) events were recorded on Turrialba volcano, Costa Rica, during a seismic field experiment in 2009. Families of LP events were previously identified and located using a joint inversion for source location and mechanism; however, the spatial resolution of the obtained locations was not sufficient for imaging the structures on which they occur. Using a waveform similarity‐based location method, we take advantage of the joint location‐mechanism inversion by relocating events around the obtained familial location. The location method is successfully tested on a synthetic data set and is then applied to the Turrialba LP data set. The relocated events are jointly interpreted with their source mechanisms and reveal an en echelon structure within the upper edifice of the volcano. This can be interpreted as a response of a shearing band with high fluid pressure inducing tensile fractures at unconsolidated rock layer interfaces within the upper edifice of the volcano.
Slab segmentation controls the interplate slip motion in the SW Hellenic subduction: New insight from the 2008Mw 6.8 Methoni interplate earthquake
Authors: Sachpazi M. , Laigle M. , Charalampakis M. , Sakellariou D. , Flueh E. , Sokos E. , Daskalaki E. , Galvé A. , Petrou P. , Hirn A.
Published: September 2016

We present an integrated approach of the seismic structure and activity along the offshore SW Hellenic subduction from combined observations of marine and land seismic stations. Our imaging of the slab top topography from teleseismic receiver function analysis at ocean bottom seismometers supports a trenchward continuation of the along‐dip slab faults beneath the Peloponnesus. We further show that their morphostructural control accounts for the backstepping of the thrust contact of the Mediterranean Ridge accretionary wedge over the upper plate. Local seismic activity offshore SW Peloponnesus constrained by ocean bottom seismometer observations reveals a correlation with specific features of the forearc: the Matapan Troughs. We study theMw 6.8 14.02.2008 interplate earthquake offshore SW Peloponnesus and show that its nucleation, rupture zone, and aftershocks sequence are confined to one slab panel between two adjacent along‐dip faults and are thus controlled by not only the offshore slab top segmentation but also the upper plate sea‐bottom morphology.
Constraining central Neo‐Tethys Ocean reconstructions with mantle convection models
Authors: Nerlich Rainer , Colli Lorenzo , Ghelichkhan Siavash , Schuberth Bernhard , Bunge Hans‐Peter
Published: September 2016

A striking feature of the Indian Ocean is a distinct geoid low south of India, pointing to a regionally anomalous mantle density structure. Equally prominent are rapid plate convergence rate variations between India and SE Asia, particularly in Late Cretaceous/Paleocene times. Both observations are linked to the central Neo‐Tethys Ocean subduction history, for which competing scenarios have been proposed. Here we evaluate three alternative reconstructions by assimilating their associated time‐dependent velocity fields in global high‐resolution geodynamic Earth models, allowing us to predict the resulting seismic mantle heterogeneity and geoid signal. Our analysis reveals that a geoid low similar to the one observed develops naturally when a long‐lived back‐arc basin south of Eurasia's paleomargin is assumed. A quantitative comparison to seismic tomography further supports this model. In contrast, reconstructions assuming a single northward dipping subduction zone along Eurasia's margin or models incorporating a temporary southward dipping intraoceanic subduction zone cannot sufficiently reproduce geoid and seismic observations.
On the atmospheric response experiment to a Blue Arctic Ocean
Authors: Nakamura Tetsu , Yamazaki Koji , Honda Meiji , Ukita Jinro , Jaiser Ralf , Handorf Dörthe , Dethloff Klaus
Published: September 2016

We demonstrated atmospheric responses to a reduction in Arctic sea ice via simulations in which Arctic sea ice decreased stepwise from the present‐day range to an ice‐free range. In all cases, the tropospheric response exhibited a negative Arctic Oscillation (AO)‐like pattern. An intensification of the climatological planetary‐scale wave due to the present‐day sea ice reduction on the Atlantic side of the Arctic Ocean induced stratospheric polar vortex weakening and the subsequent negative AO. Conversely, strong Arctic warming due to ice‐free conditions across the entire Arctic Ocean induced a weakening of the tropospheric westerlies corresponding to a negative AO without troposphere‐stratosphere coupling, for which the planetary‐scale wave response to a surface heat source extending to the Pacific side of the Arctic Ocean was responsible. Because the resultant negative AO‐like response was accompanied by secondary circulation in the meridional plane, atmospheric heat transport into the Arctic increased, accelerating the Arctic amplification.
Early growth dynamical implications for the steerability of stratospheric solar radiation management via sulfur aerosol particles
Authors: Benduhn François , Schallock Jennifer , Lawrence Mark G.
Published: September 2016

Aerosol growth dynamics may have implications for the steerability of stratospheric solar radiation management via sulfur particles. This paper derives a set of critical initial growth conditions that are analyzed as a function of two key parameters: the initial concentration of the injected sulfuric acid and its dilution rate with the surrounding air. Based upon this analysis, early aerosol growth dynamical regimes may be defined and classified in terms of their likelihood to serve as candidates for the controlled generation of a radiatively effective aerosol. Our results indicate that the regime that fulfills all critical conditions would require that airplane turbines be used to provide sufficient turbulence. The regime's parameter space is narrow and related to steep gradients, thus pointing to potential fine tuning requirements. More research, development, and testing would be required to refine our findings and determine their global‐scale implications.
Evidence for shallow megathrust slip across the Unalaska seismic gap during the great 1957 Andreanof Islands earthquake, eastern Aleutian Islands, Alaska
Authors: Nicolsky D. J. , Freymueller J. T. , Witter R. C. , Suleimani E. N. , Koehler R. D.
Published: September 2016

We reassess the slip distribution of the 1957 Andreanof Islands earthquake in the eastern part of the aftershock zone where published slip models infer little or no slip. Eyewitness reports, tide gauge data, and geological evidence for 9–23 m tsunami runups imply seafloor deformation offshore Unalaska Island in 1957, in contrast with previous studies that labeled the area a seismic gap. Here we simulate tsunami dynamics for a suite of deformation models that vary in depth and amount of megathrust slip. Tsunami simulations show that a shallow (5–15 km deep) rupture with ~20 m of slip most closely reproduces the 1957 Dutch Harbor marigram and nearby >18 m runup at Sedanka Island marked by stranded drift logs. Slip models >20 km deep predict waves that arrive too soon. Our results imply that shallow slip on the megathrust in 1957 extended east into an area that presently creeps.
SMAP observes flooding from land to sea: The Texas event of 2015
Authors: Fournier S. , Reager J. T. , Lee T. , Vazquez‐Cuervo J. , David C. H. , Gierach M. M.
Published: September 2016

Floods can have damaging impacts on both land and sea, yet studies of flooding events tend to focus on only one side of the land/sea continuum. Here we present the first two‐sided analysis, focusing on the May 2015 severe flooding in Texas. Our investigation benefits from simultaneous measurements of land surface soil moisture and sea surface salinity from NASA's recent Soil Moisture Active Passive (SMAP) mission as well as ancillary data. We report the comprehensive chronology of the flooding: above average rainfall preceding the flood caused soils to saturate; record rainfall then generated record river discharge; and subsequently, an unusual freshwater plume associated with anomalous ocean currents formed in the north central Gulf of Mexico. Together with the Mississippi River plume, a rare “horseshoe” pattern was created that may have significant biogeochemical implications. Such integrated land/sea analysis of flood evolution can improve impact assessments of future extreme flooding events.
Bursty bulk flows at different magnetospheric activity levels: Dependence on IMF conditions
Authors: Zhang L. Q. , Baumjohann W. , Wang C. , Dai L. , Tang B. B
Published: September 2016

Based on concurrent observations of the ACE and Geotail satellites from 1998 to 2005, we statistically analyzed and compared the earthward bursty bulk flows (BBFs) with local positive Bz under different interplanetary magnetic field (IMF) conditions. Four different magnetospheric activity levels (MALs), including quiet times and substorm growth/expansion/recovery phases, are considered. The properties of the BBFs, including their ion temperature (T), Vx component, x component of the energy flux density (Qx), and the solar wind dawn‐dusk electric field Ey (observed at ~1 AU), are analyzed. Main observations include the following: (1) BBF tends to have less penetration distance for northward IMF (NW‐IMF) than for southward IMF (SW‐IMF). Inward of 15 RE the BBFs for SW‐IMF are dominant. Few BBFs for NW‐IMF occur within 15 RE. (2) The occurrence probabilities of the BBFs at each MAL depend highly on the orientations of the IMF. During quiet times, the BBFs for NW‐IMF are dominant. Reversely, during the growth and expansion phases of a substorm, the BBFs for SW‐IMF are dominant. (3) The strengths of the BBF have significant evolution with substorm development. For SW‐IMF condition, the strengths of the BBFs are the lowest for quiet times. The strength of the BBFs tends to increase during the growth phase and reaches to the strongest value during the expansion phase, then, decays during the recovery phase. For NW‐IMF condition, the strengths of the BBFs evolve with the substorm development in a similar way as for SW‐IMF condition. (4) For SW‐IMF, the solar wind Ey evolves with the substorm development in a similar way to the strength of the BBFs. However, no clear evolution is found for NW‐IMF. (5) The strengths of the BBF Qx and solar wind Ey are closely related. Both tend to be stronger for growth phase than for quite time, reach the strongest for expansion phase, then decay for recovery phase. It appears that to trigger a substorm, the strength of the BBFs should achieve energy thresholds with values different for NW‐IMF and SW‐IMF.
Variations of ionospheric plasma at different altitudes before the 2005 Sumatra Indonesia Ms 7.2 earthquake
Authors: Liu Jing , Zhang Xuemin , Novikov Victor , Shen Xuhui
Published: September 2016

In recent years, many researchers pay more attention to abnormities before earthquake, and in this study, seismo‐ionospheric synchronous disturbances at different altitudes by GPS and satellite observations were first studied around one Sumatra Indonesia Ms 7.2 earthquake that occurred on 5 July 2005. By using the same temporal and spatial methods, data of GPS‐total electron content (TEC) from Jet Propulsion Laboratory, electron density (Ne) from Detection of Electro‐Magnetic Emissions Transmitted from Earthquake Regions, and ion density (Ni) from Defense Meteorological Satellite Program were deeply analyzed. The ionospheric plasma disturbances in GPS‐TEC and increasement of Ne at 710 km were found on 4 July, and plasma density at the three altitudes has all increased on 7 July after the earthquake. All the disturbances were not just above the epicenter. TEC perturbations have happened at the east of the epicenter for the two days, and electron density enhancement at 710 km has moved to west of the TEC perturbations at the same time on 4 July, which may be caused by E × B drift. The moving direction of upgoing plasma was simulated using SAMI2 model. The results have shown that the plasma will move to higher altitude along the geomagnetic force line, which could exactly account for the plasma density enhancement in the northern direction of the geomagnetic south latitude earthquake.
Remote forcing of subsurface currents and temperatures near the northern limit of the California Current System
Authors: Engida Zelalem , Monahan Adam , Ianson Debby , Thomson Richard E.
Published: September 2016

Local and remote wind forcing of upwelling along continental shelves of coastal upwelling regions play key roles in driving biogeochemical fluxes, including vertical net fluxes of carbon and nutrients. These fluxes are responsible for high primary productivity, which in turn supports a lucrative fishery in these regions. However, the relative contributions of local versus remote wind forcing are not well quantified or understood. We present results of coherence analyses between currents at a single mooring site (48.5°N, 126°W) in the northern portion of the California Current System (CalCS) from 1989 to 2008 and coincident time series of North America Regional Reanalysis (NARR) 10 m wind stress within the CalCS (36–54°N, 120–132°W). The two‐decade‐long current records from the three shallowest depths (35, 100, and 175 m) show a remote response to winds from south as far as 36°N. In contrast, only temperatures at the deepest depth (400 m) show strong coherences with remote winds. Weaker local wind influence is observed in both the currents and 400 m temperatures but is mostly due to the large spatial coherence within the wind field itself. Lack of coherence between distal winds and the 400 m currents suggests that the temperature variations at that depth are driven by vertical motion resulting from poleward travelling coastal trapped waves (CTWs). Understanding the effects of remote forcing in coastal upwelling regions is necessary for determining the occurrence and timing of extreme conditions in coastal oceans, and their subsequent impact on marine ecosystems.
Improving the simulation of landfast ice by combining tensile strength and a parameterization for grounded ridges
Authors: Lemieux Jean‐François , Dupont Frédéric , Blain Philippe , Roy François , Smith Gregory C. , Flato Gregory M.
Published: September 2016

In some coastal regions of the Arctic Ocean, grounded ice ridges contribute to stabilizing and maintaining a landfast ice cover. Recently, a grounding scheme representing this effect on sea ice dynamics was introduced and tested in a viscous‐plastic sea ice model. This grounding scheme, based on a basal stress parameterization, improves the simulation of landfast ice in many regions such as in the East Siberian Sea, the Laptev Sea, and along the coast of Alaska. Nevertheless, in some regions like the Kara Sea, the area of landfast ice is systematically underestimated. This indicates that another mechanism such as ice arching is at play for maintaining the ice cover fast. To address this problem, the combination of the basal stress parameterization and tensile strength is investigated using a 0.25° Pan‐Arctic CICE‐NEMO configuration. Both uniaxial and isotropic tensile strengths notably improve the simulation of landfast ice in the Kara Sea but also in the Laptev Sea. However, the simulated landfast ice season for the Kara Sea is too short compared to observations. This is especially obvious for the onset of the landfast ice season which systematically occurs later in the model and with a slower build up. This suggests that improvements to the sea ice thermodynamics could reduce these discrepancies with the data.