bluuebunny/crossref_metadata_2025 huggingface dataset:
Culture, connaissance et réduction des risques de catastrophe : liens critiques pour une transformation sociétale durable
Authors: Weichselgartner Juergen , Norton John , Chantry Guillaume , Brévière Emilie , Pigeon Patrick , Guézo Bernard
Published: January 2017

Les politiques et les pratiques concernant la réduction des risques de catastrophe dépendent largement des spécificités socio-culturelles et des connaissances qu’en ont les individus. Bien que la culture et le savoir soient des facteurs essentiels pour réduire ces risques, ils sont rarement traités ensemble de façon systématique et approfondie, que ce soit dans les études ou les programmes d’actions. Nous soutenons qu’une exploitation plus approfondie des résultats de la recherche sur les systèmes de la culture et de la connaissance est de nature à améliorer considérablement l’efficacité des mesures décidées pour l’atténuation des catastrophes. Cet article aborde comment la culture et la connaissance contribuent à la réduction des risques de catastrophe et en décrit des défis majeurs. Il présente également une approche conceptuelle qui permet de saisir les différents niveaux qualitatifs de la compréhension : les faits, les données, l’information, la connaissance et la sagesse. Tout au long de l’article, nous mobilisons des exemples empruntés au Viet Nam afin d’illustrer des cas courants de pratiques culturelles, économiques et populaires qui prévalent sur les logiques institutionnelles en matière de réduction des risques de catastrophe. Ces pratiques révèlent les éléments qui provoquent la fragmentation du savoir. Orienter les objets de recherche vers des questions de connaissance culturelle et sociale conduirait à mieux saisir les processus structuraux qui favorisent la vulnérabilité face aux catastrophes, ainsi que les processus socio-culturels qui construisent notre compréhension des risques de catastrophe.
Influence des pressions anthropiques sur la structure des populations de Pentadesma butyracea au Bénin
Authors: Dicko Aliou , Biaou Samadori Sorotori Honoré , Natta Armand Kuyema , Aboudou Salami Gado Choukouratou , Kouagou M’Mouyohoum
Published: January 2017

La présente étude examine l’influence des pressions anthropiques sur les caractéristiques structurales des populations de Pentadesma butyracea Sabine (Clusiaceae), une espèce ligneuse vulnérable et à but multiple. Au total 116 placeaux de 500 m² ont été installés de façon aléatoire, dont 68 dans la zone soudanienne et 48 dans la zone soudano-guinéenne, pour réaliser les mesures dendrométriques et inventaires floristiques. Les populations de P. butyracea ont été catégorisées suivant les pressions anthropiques auxquelles elles sont sujettes à l’aide d’une Analyse factorielle des correspondances (AFC). Trois groupes ont été discriminés : le groupe1 (populations de Penessoulou et de Kandi) est caractérisé par une forte pression due aux feux de végétation et aux activités agricoles ; le groupe 2 (populations de Manigri et de Ségbana) est caractérisé par des coupes fréquentes de bois, l’écorçage régulier de P. butyracea, l’élagage de P. butyracea et la pâture des animaux dans les galeries ; et le groupe 3 (populations de Natitingou, Toucountouna et Tchaourou) est caractérisé par un fort niveau de ramassage des fruits de P. butyracea et d’extraction de sable dans les galeries. La répartition par classes de diamètre donne des structures en cloche avec une dissymétrie gauche ou droite selon les types de pressions auxquelles les populations discriminées sont soumises. Pour une conservation des populations de P. butyracea, les forêts galeries très dégradées doivent faire l’objet de reboisement et des mesures de protection doivent être mises en œuvre dans les populations peu dégradées.
Mechanisms of Impaired Neutrophil Migration by MicroRNAs in Myelodysplastic Syndromes
Authors: Cao Meiwan , Shikama Yayoi , Kimura Hideo , Noji Hideyoshi , Ikeda Kazuhiko , Ono Tomoyuki , Ogawa Kazuei , Takeishi Yasuchika , Kimura Junko
Published: January 2017

In myelodysplastic syndromes (MDS), functional defects of neutrophils result in high mortality because of infections; however, the molecular basis remains unclear. We recently found that miR-34a and miR-155 were significantly increased in MDS neutrophils. To clarify the effects of the aberrant microRNA expression on neutrophil functions, we introduced miR-34a, miR-155, or control microRNA into neutrophil-like differentiated HL60 cells. Ectopically introduced miR-34a and miR-155 significantly attenuated migration toward chemoattractants fMLF and IL-8, but enhanced degranulation. To clarify the mechanisms for inhibition of migration, we studied the effects of miR-34a and miR-155 on the migration-regulating Rho family members, Cdc42 and Rac1. The introduced miR-34a and miR-155 decreased the fMLF-induced active form of Cdc42 to 29.0 ± 15.9 and 39.7 ± 4.8% of that in the control cells, respectively, although Cdc42 protein levels were not altered. miR-34a decreased a Cdc42-specific guanine nucleotide exchange factor (GEF), dedicator of cytokinesis (DOCK) 8, whereas miR-155 reduced another Cdc42-specific GEF, FYVE, RhoGEF, and PH domain-containing (FGD) 4. The knockdown of DOCK8 and FGD4 by small interfering RNA suppressed Cdc42 activation and fMLF/IL-8–induced migration. miR-155, but not miR-34a, decreased Rac1 protein, and introduction of Rac1 small interfering RNA attenuated Rac1 activation and migration. Neutrophils from patients showed significant attenuation in migration compared with healthy cells, and protein levels of DOCK8, FGD4, and Rac1 were well correlated with migration toward fMLF (r = 0.642, 0.686, and 0.436, respectively) and IL-8 (r = 0.778, 0.659, and 0.606, respectively). Our results indicated that reduction of DOCK8, FGD4, and Rac1 contributes to impaired neutrophil migration in MDS.
Amino Acid Catabolism in Multiple Sclerosis Affects Immune Homeostasis
Authors: Negrotto Laura , Correale Jorge
Published: January 2017

Amino acid catabolism has been implicated in immunoregulatory mechanisms present in several diseases, including autoimmune disorders. Our aims were to assess expression and activity of enzymes involved in Trp and Arg catabolism, as well as to investigate amino acid catabolism effects on the immune system of multiple sclerosis (MS) patients. To this end, 40 MS patients, 30 healthy control subjects, and 30 patients with other inflammatory neurological diseases were studied. Expression and activity of enzymes involved in Trp and Arg catabolism (IDO1, IDO2, Trp 2,3-dioxygenase [TDO], arginase [ARG] 1, ARG2, inducible NO synthetase) were evaluated in PBMCs. Expression of general control nonrepressed 2 serine/threonine kinase and mammalian target of rapamycin (both molecules involved in sensing amino acid levels) was assessed in response to different stimuli modulating amino acid catabolism, as were cytokine secretion levels and regulatory T cell numbers. The results demonstrate that expression and activity of IDO1 and ARG1 were significantly reduced in MS patients compared with healthy control subjects and other inflammatory neurological diseases. PBMCs from MS patients stimulated with a TLR-9 agonist showed reduced expression of general control nonrepressed 2 serine/threonine kinase and increased expression of mammalian target of rapamycin, suggesting reduced amino acid catabolism in MS patients. Functionally, this reduction resulted in a decrease in regulatory T cells, with an increase in myelin basic protein–specific T cell proliferation and secretion of proinflammatory cytokines. In contrast, induction of IDO1 using CTLA-4 or a TLR-3 ligand dampened proinflammatory responses. Overall, these results highlight the importance of amino acid catabolism in the modulation of the immunological responses in MS patients. Molecules involved in these pathways warrant further exploration as potential new therapeutic targets in MS.
MLKL Activation Triggers NLRP3-Mediated Processing and Release of IL-1β Independently of Gasdermin-D
Authors: Gutierrez Kimberley D. , Davis Michael A. , Daniels Brian P. , Olsen Tayla M. , Ralli-Jain Pooja , Tait Stephen W. G. , Gale Michael , Oberst Andrew
Published: January 2017

Necroptosis is a form of programmed cell death defined by activation of the kinase receptor interacting protein kinase 3 and its downstream effector, the pseudokinase mixed lineage kinase domain-like (MLKL). Activated MLKL translocates to the cell membrane and disrupts it, leading to loss of cellular ion homeostasis. In this study, we use a system in which this event can be specifically triggered by a small-molecule ligand to show that MLKL activation is sufficient to induce the processing and release of bioactive IL-1β. MLKL activation triggers potassium efflux and assembly of the NLRP3 inflammasome, which is required for the processing and activity of IL-1β released during necroptosis. Notably, MLKL activation also causes cell membrane disruption, which allows efficient release of IL-1β independently of the recently described pyroptotic effector gasdermin-D. Taken together, our findings indicate that MLKL is an endogenous activator of the NLRP3 inflammasome, and that MLKL activation provides a mechanism for concurrent processing and release of IL-1β independently of gasdermin-D.
Regional impacts of tourism-led growth on poverty and income inequality
Authors: Mahadevan Renuka , Amir Hidayat , Nugroho Anda
Published: January 2017

This study finds that an increase in Indonesia’s domestic and foreign tourism led to a reduction in poverty and an increase in income inequality in both rural and urban regions. The important finding that greater reductions in poverty were accompanied by greater increases in income inequality highlights the difficulty in addressing this trade-off from a tourism boost. Accompanying policies, such as investment to raise labour productivity in tourism-related sectors of hotels and restaurants, led to greater poverty reduction than a cash transfer policy. The cash transfer policy, on the other hand, reduced urban poverty but did not increase urban income inequality, unlike in the rural areas. Thus, there is no ‘one size fits all’ policy to address poverty and income inequality in rural and urban areas, and whether or not policies need to be targeted differently for touristic and non-touristic urban/rural regions is an area for future research.
Understanding the impact of Turkish TV series on inbound tourists
Authors: Kantarci Kemal , Başaran Murat Alper , Özyurt Paşa Mustafa
Published: January 2017

Turkey has earned outstanding success in exporting TV series. It is believed that one of the most important results of exporting TV series is to have impact on the increment of the travel demand to Turkey, which is known as film-induced tourism effect. This field emerging recently deals with investigating the impact of TV series and movies on tourism demand. In this article, using Chow analysis whether to influence or not the citizens of Saudis and Bulgarians as visitors to Turkey is examined. It is concluded that while for Saudis, tourism demand to Turkey increases considerably after the broadcast of TV series, the same situation cannot be drawn for Bulgarians.
The euro crisis, fiscal devaluation, and impacts on the tourism sector in the Spanish economy
Authors: Sastre Francesc , Rey-Maquieira Javier , Arbulú Italo
Published: January 2017

The current account imbalances between northern and southern euro area countries from 1998 to 2007 have been considered one of the key problems in the euro crisis. Cumulated over 12 years, the sustained differentials of high inflations in south countries led to a cumulative price differential relative to the north countries and contributed to the deterioration in competitiveness. In addition, south countries cannot use nominal currency devaluation, as it used to do before. Because of the high costs of internal devaluation, the policy option of a tax combination can replicate the effects attained under nominal exchange rate devaluation. In this article, we analyze the impacts of a fiscal devaluation on the tourism sector in the case of Spanish economy.
Capital Structure Theory: An Overview
Authors: Abeywardhana D.K.Y
Published: January 2017

Capital structure is still a puzzle among finance scholars. Purpose of this study is to review various capital structure theories that have been proposed in the finance literature to provide clarification for the firms’ capital structure decision. Starting from the capital structure irrelevance theory of Modigliani and Miller (1958) this review examine the several theories that have been put forward to explain the capital structure.Three major theories emerged over the years following the assumption of the perfect capital market of capital structure irrelevance model. Trade off theory assumes that firms have one optimal debt ratio and firm trade off the benefit and cost of debt and equity financing. Pecking order theory (Myers, 1984, Myers and Majluf, 1984) assumes that firms follow a financing hierarchy whereby minimize the problem of information asymmetry. But neither of these two theories provide a complete description why some firms prefer debt and others prefer equity finance under different circumstances.Another theory of capital structure has introduced recently by, Baker and Wurgler (2002), market timing theory, which  explains the current capital structure as the cumulative outcome of past attempts to time the equity market. Market timing issuing behaviour has been well established empirically by others already, but Baker and Wurgler (2002) show that the influence of market timing on capital structure is regular and continuous. So the predictions of these theories sometimes acted in a contradictory manner and Myers (1984) 32 years old question “How do firms choose their capital structure?” still remains.
The Demographics’ Effects on Organizational Culture, Organizational Citizenship Behavior and Job Satisfaction: Evidence from Egypt and Mexico
Authors: Badawy Tarek A. El , Trujillo-Reyes Juana Cecilia , Magdy Mariam M.
Published: January 2017

The aim of this study was to examine the effect of several demographic variables on organizational culture, organizational citizenship behavior and job satisfaction. This comparative study extracted two samples from Egypt (127 participants) and Mexico (116 participants). Participants answered a 7-point Likert scale questionnaire and SPSS software was used to analyze the data.  Results showed no demographic effect on the three constructs. From Egypt, differences were only observed in on the managerial level regarding the market organizational culture. Results also showed significant results from Mexico on the managerial level and job satisfaction, organizational citizenship behavior, and clan and adhocracy organizational cultures. Further implications and future research directions are provided.
Stimulus relevance modulates contrast adaptation in visual cortex
Authors: Keller Andreas J , Houlton Rachael , Kampa Björn M , Lesica Nicholas A , Mrsic-Flogel Thomas D , Keller Georg B , Helmchen Fritjof
Published: January 2017

A general principle of sensory processing is that neurons adapt to sustained stimuli by reducing their response over time. Most of our knowledge on adaptation in single cells is based on experiments in anesthetized animals. How responses adapt in awake animals, when stimuli may be behaviorally relevant or not, remains unclear. Here we show that contrast adaptation in mouse primary visual cortex depends on the behavioral relevance of the stimulus. Cells that adapted to contrast under anesthesia maintained or even increased their activity in awake naïve mice. When engaged in a visually guided task, contrast adaptation re-occurred for stimuli that were irrelevant for solving the task. However, contrast adaptation was reversed when stimuli acquired behavioral relevance. Regulation of cortical adaptation by task demand may allow dynamic control of sensory-evoked signal flow in the neocortex.
Sylvia Plath's “Mirror” and Forough Farrokhzad’s “The Bird May Die” Comparative Analysis from a Mystical Perspective
Authors: Mohammad pour Mohsen , Valizade Hossein
Published: January 2017

Sylvia Plath’s mirror and Forough Farrokhzad’s the bird may die are two of the best known poems in the aspect of femininity, fighting for feminine rights and equality. The two poets though living distances apart, respectively in America and Iran, had the same poetic perspectives. These poems can be viewed in the aspect of mysticism and mystical state. The term mysticism defined by William James and Frederick Crossfield Happold, is a state of mind experiencing the finding of the hidden truth and the true self. Many have said that the poem mirror dictates the feministic aspect of Sylvia Plath's life, and how women are visualized or valued by men, or that the poem demonstrates the aging of Plath into a wise and old woman. In this paper however we aim to introduce another perspective in which claims Sylvia Plath's mirror seeks mysticism and finding the true self. The narrator in the poem, first a mirror and then a lake, thinks its reflections out loud. This paper also aims to relate this matter to Forough Farrokhzad's poem the bird may die, a poem believed by critics to state the sufferings from social injustice of her time, though now seen through mystical spectacles. In the poem Farrokhzad declares her sorrow of darkness, and seeks an invitation to the birds’ feast. Furthermore, this paper briefly introduces the troubled life of the two poets demonstrating the similarities of their situation and circumstances, and the effect of these difficulties on their poetry. On this paper first mysticism, it’s definition and theoretical studies by William James and Frederick Crossfield Happold are introduced, followed by a brief biography of Sylvia Plath and Forough Farrokhzad, stating the difficulties and problems they encountered, and then the mystical analysis of the two poems, analyzing each line for elements, metaphors, and symbolic features through a mystical point of view, are indicated accordingly. The bird, mirror, lake, night, water, fish, moon, and sun are all signs and symbols the poets used to demonstrate seeking mysticism, reality, and finding the true self, and also the obstacles which prevents them to do so. These two poems were the latest works of the poets, before they committed suicide.
The PufX quinone channel enables the light‐harvesting 1 antenna to bind more carotenoids for light collection and photoprotection
Authors: Olsen John D. , Martin Elizabeth C. , Hunter C. Neil
Published: January 2017

Photosynthesis in some phototrophic bacteria requires the PufX component of the reaction centre–light‐harvesting 1–PufX (RC‐LH1‐PufX) complex, which creates a pore for quinone/quinol (Q/QH2) exchange across the LH1 barrier surrounding the RC. However, photosynthetic bacteria such as Thermochromatium (T.) tepidum do not require PufX because there are fewer carotenoid binding sites, which creates multiple pores in the LH1 ring for Q/QH2 exchange. We show that an αTrp‐24→Phe alteration of the Rhodobacter (Rba.) sphaeroides LH1 antenna impairs carotenoid binding and allows photosynthetic growth in the absence of PufX. We propose that acquisition of PufX and confining Q/QH2 traffic to a pore adjacent to the RC QB site is an evolutionary upgrade that allows increased LH1 carotenoid content for enhanced light absorption and photoprotection.
Direct measurement of Vorticella contraction force by micropipette deflection
Authors: France Danielle , Tejada Jonathan , Matsudaira Paul
Published: January 2017

The ciliated protozoan Vorticella convallaria is noted for its exceptionally fast adenosine triphosphate‐independent cellular contraction, but direct measurements of contractile force have proven difficult given the length scale, speed, and forces involved. We used high‐speed video microscopy to image live Vorticella stalled in midcontraction by deflection of an attached micropipette. Stall forces correlate with both distance contracted and the resting stalk length. Estimated isometric forces range from 95 to 177 nanonewtons (nN), or 1.12 nN·μm−1 of the stalk. Maximum velocity and work are also proportional to distance contracted. These parameters constrain proposed biochemical/physical models of the contractile mechanism.
How can satellite imagery be used for mineral exploration in thick vegetation areas?
Authors: Hede Arie Naftali Hawu , Koike Katsuaki , Kashiwaya Koki , Sakurai Shigeki , Yamada Ryoichi , Singer Donald A.
Published: January 2017

The Hokuroku district, northern Japan, is globally recognized for rich ore deposits (kuroko and vein types), which have been thoroughly explored under thick vegetation cover. This situation is ideal to evaluate the effects of ore deposits on vegetation anomalies through geobotanical remote sensing. Here we present novel methods to detect vegetation anomalies caused by ore deposits and verify their usefulness by comparing the anomalies with a deposit potential map produced from multiple geological data. We use the reflectance spectra of Landsat ETM+ images acquired in summer and autumn to calculate a vegetation index for plant physiological activity. A key variable to detect the anomalies is a variation of vegetation index with time at each pixel. Difference in variation is enlarged by a sequence of image enhancement methods for the detection. We find that the vegetation anomalies, defined by the large ratios, correspond well to the high potential zones of ore deposits and known major deposits. Consequently, our methods can extend the applicability of remote sensing‐based mineral exploration to the areas covered by thick vegetation, in addition to traditional arid and semiarid areas.
Classification of geochemical data based on multivariate statistical analyses: Complementary roles of cluster, principal component, and independent component analyses
Authors: Iwamori Hikaru , Yoshida Kenta , Nakamura Hitomi , Kuwatani Tatsu , Hamada Morihisa , Haraguchi Satoru , Ueki Kenta
Published: January 2017

Identifying the data structure including trends and groups/clusters in geochemical problems is essential to discuss the origin of sources and processes from the observed variability of data. An increasing number and high dimensionality of recent geochemical data require efficient and accurate multivariate statistical analysis methods. In this paper, we show the relationship and complementary roles of k‐means cluster analysis (KCA), principal component analysis (PCA), and independent component analysis (ICA) to capture the true data structure. When the data are preprocessed by primary standardization (i.e., with the zero mean and normalized by the standard deviation), KCA and PCA provide essentially the same results, although the former returns the solution in a discretized space. When the data are preprocessed by whitening (i.e., normalized by eigenvalues along the principal components), KCA and ICA may identify a set of independent trends and groups, irrespective of the amplitude (power) of variance. As an example, basalt isotopic compositions have been analyzed with KCA on the whitened data, demonstrating clear rock type/tectonic occurrence/mantle end‐member discrimination. Therefore, the combination of these methods, particularly KCA on whitened data, is useful to capture and discuss the data structure of various geochemical systems, for which an Excel program is provided.
Upper mantle seismic anisotropy beneath the Northern Transantarctic Mountains, Antarctica from PKS, SKS, and SKKS splitting analysis
Authors: Graw Jordan H. , Hansen Samantha E.
Published: January 2017

Using data from the new Transantarctic Mountains Northern Network, this study aims to constrain azimuthal anisotropy beneath a previously unexplored portion of the Transantarctic Mountains (TAMs) to assess both past and present deformational processes occurring in this region. Shear‐wave splitting parameters have been measured for PKS, SKS, and SKKS phases using the eigenvalue method within the SplitLab software package. Results show two distinct geographic regions of anisotropy within our study area: one behind the TAMs front, with an average fast axis direction of 42 ± 3° and an average delay time of 0.9 ± 0.04 s, and the other within the TAMs near the Ross Sea coastline, with an average fast axis oriented at 51 ± 5° and an average delay time of 1.5 ± 0.08 s. Behind the TAMs front, our results are best explained by a single anisotropic layer that is estimated to be 81–135 km thick, thereby constraining the anisotropic signature within the East Antarctic lithosphere. We interpret the anisotropy behind the TAMs front as relict fabric associated with tectonic episodes occurring early in Antarctica's geologic history. For the coastal stations, our results are best explained by a single anisotropic layer estimated to be 135–225 km thick. This places the anisotropic source within the viscous asthenosphere, which correlates with low seismic velocities along the edge of the West Antarctic Rift System. We interpret the coastal anisotropic signature as resulting from active mantle flow associated with rift‐related decompression melting and Cenozoic extension.
An evaluation of benthic foraminiferal U/Ca and U/Mn proxies for deep ocean carbonate chemistry and redox conditions
Authors: Chen Pujiao , Yu Jimin , Jin Zhangdong
Published: January 2017

The deep ocean is thought to have played a crucial role in modulating atmospheric CO2 changes, and thus reconstructions of deep ocean conditions can place important constraints on the past global carbon cycle. Some previous studies suggested that foraminiferal U/Ca could be used to infer seawater carbonate chemistry changes, but others showed complications from diagenesis and temperature. A recent downcore study suggested that foraminiferal U/Mn may be used for sedimentary redox‐conditions, but no core‐top work has been done to investigate factors affecting U/Mn. We investigate controlling factors on U/Ca and U/Mn in two benthic foraminiferal species from 120 global core‐tops and three Atlantic sediment cores. Our core‐top data reveal no significant correlation between core‐top benthic U/Ca and carbonate system parameters. The lack of an influence of deep‐water [
] on U/Ca is further supported by our downcore results. Together, our data highlight complications to use benthic U/Ca for deep‐water carbonate chemistry reconstructions. Although no correlation is found between core‐top U/Mn and hydrographic data, high‐resolution U/Mn and U/Ca in core TNO57‐21 show similar patterns to authigenic U (aU) and vary in tandem with atmospheric CO2 on millennial timescales. Changes in U/Mn, U/Ca and aU in TNO57‐21 may reflect postdepositional diagenesis linked to sedimentary oxygen, which is controlled by subantarctic surface productivity and ventilation of deep South Atlantic in the past. We suggest that benthic U/Mn and U/Ca may be used as auxiliary indicators for past sedimentary redox‐conditions and along with other proxies could reflect deep‐water oxygenation.
Common climatic signal from glaciers in the European Alps over the last 50 years
Authors: Vincent C. , Fischer A. , Mayer C. , Bauder A. , Galos S. P. , Funk M. , Thibert E. , Six D. , Braun L. , Huss M.
Published: January 2017

Conventional glacier‐wide mass balances are commonly used to study the effect of climate forcing on glacier melt. Unfortunately, the glacier‐wide mass balances are also influenced by the glacier's dynamic response. Investigations on the effects of climate forcing on glaciers can be largely improved by analyzing point mass balances. Using a statistical model, we have found that 52% of the year‐to‐year deviations in the point mass balances of six glaciers distributed across the entire European Alps can be attributed to a common variability. Point mass balance changes reveal remarkable regional consistencies reaching 80% for glaciers less than 10 km apart. Compared to the steady state conditions of the 1962–1982 period, the surface mass balance changes are −0.85 m water equivalent (w.e.) a−1 for 1983–2002 and −1.63 m w.e. a−1 for 2003–2013. This indicates a clear and regionally consistent acceleration of mass loss over recent decades over the entire European Alps.
Mesospheric temperatures estimated from the meteor radar observations at Mohe, China
Authors: Liu Libo , Liu Huixin , Le Huijun , Chen Yiding , Sun Yang‐Yi , Ning Baiqi , Hu Lianhuan , Wan Weixing , Li Na , Xiong Jiangang
Published: January 2017

In this work, we report the estimation of mesospheric temperatures at 90 km height from the observations of the VHF all‐sky meteor radar operated at Mohe (53.5°N, 122.3°E), China, since August 2011. The kinetic temperature profiles retrieved from the observations of Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) on board the Thermosphere, Ionosphere, Mesosphere, Energetics, and Dynamics satellite are processed to provide the temperature (TSABER) and temperature gradient (dT/dh) at 90 km height. Based on the SABER temperature profile data an empirical dT/dh model is developed for the Mohe latitude. First, we derive the temperatures from the meteor decay times (Tmeteor) and the Mohe dT/dh model gives prior information of temperature gradients. Second, the full width at half maximum (FWHM) of the meteor height profiles is calculated and further used to deduce the temperatures (TFWHM) based on the strong linear relationship between FWHM and TSABER. The temperatures at 90 km deduced from the decay times (Tmeteor) and from the meteor height distributions (TFWHM) at Mohe are validated/calibrated with TSABER. The temperatures present a considerable annual variation, being maximum in winter and minimum in summer. Harmonic analyses reveal that the temperatures have an annual variation consistent with TSABER. Our work suggests that FWHM has a good performance in routine estimation of the temperatures. It should be pointed out that the slope of FWHM as a function of TSABER is 10.1 at Mohe, which is different from that of 15.71 at King Sejong (62.2°S, 58.8°E) station.
High‐resolution photography of clouds from the surface: Retrieval of optical depth of thin clouds down to centimeter scales
Authors: Schwartz Stephen E. , Huang Dong , Vladutescu Daniela Viviana
Published: January 2017

This paper describes the approach and presents initial results, for a period of several minutes in north central Oklahoma, of an examination of clouds by high‐resolution digital photography from the surface looking vertically upward. A commercially available camera having 35 mm equivalent focal length up to 1200 mm (nominal resolution as fine as 6 µrad, which corresponds to 9 mm for cloud height 1.5 km) is used to obtain a measure of zenith radiance of a 30 m × 30 m domain as a two‐dimensional image consisting of 3456 × 3456 pixels (12 million pixels). Downwelling zenith radiance varies substantially within single images and between successive images obtained at 4 s intervals. Variation in zenith radiance found on scales down to about 10 cm is attributed to variation in cloud optical depth (COD). Attention here is directed primarily to optically thin clouds; COD less than about 2. A radiation transfer model used to relate downwelling zenith radiance to COD and to relate the counts in the camera image to zenith radiance permits determination of COD on a pixel‐by‐pixel basis. COD for thin clouds determined in this way exhibits considerable variation, for example, an order of magnitude within 15 m, a factor of 2 within 4 m, and 25% (0.12 to 0.15) over 14 cm. This approach, which examines cloud structure on scales 3 to 5 orders of magnitude finer than satellite products, opens new avenues for examination of cloud structure and evolution.
Evaluating hillslope and riparian contributions to dissolved nitrogen (N) export from a boreal forest catchment
Authors: Blackburn M. , Ledesma José L. J. , Näsholm Torgny , Laudon Hjalmar , Sponseller Ryan A.
Published: January 2017

Catchment science has long held that the chemistry of small streams reflects the landscapes they drain. However, understanding the contribution of different landscape units to stream chemistry remains a challenge which frequently limits our understanding of export dynamics. For limiting nutrients such as nitrogen (N), an implicit assumption is that the most spatially extensive landscape units (e.g., uplands) act as the primary sources to surface waters, while near‐stream zones function more often as sinks. These assumptions, based largely on studies in high‐gradient systems or in regions with elevated inputs of anthropogenic N, may not apply to low‐gradient, nutrient‐poor, and peat‐rich catchments characteristic of many northern ecosystems. We quantified patterns of N mobilization along a hillslope transect in a northern boreal catchment to assess the extent to which organic matter‐rich riparian soils regulate the flux of N to streams. Contrary to the prevailing view of riparian functioning, we found that near‐stream, organic soils supported concentrations and fluxes of ammonium (NH4+) and dissolved organic nitrogen that were much higher than the contributing upslope forest soils. These results suggest that stream N chemistry is connected to N mobilization and mineralization within the riparian zone rather than the wider landscape. Results further suggest that water table fluctuation in near‐surface riparian soils may promote elevated rates of net N mineralization in these landscapes.
Estimating belowground carbon stocks in peatlands of the Ecuadorian páramo using ground‐penetrating radar (GPR)
Authors: Comas Xavier , Terry Neil , Hribljan John A. , Lilleskov Erik A. , Suarez Esteban , Chimner Rodney A. , Kolka Randy K.
Published: January 2017

The páramo ecoregion of Ecuador contains extensive peatlands that are known to contain carbon (C) dense soils capable of long‐term C storage. Although high‐altitude mountain peatlands are typically small when compared to low‐altitude peatlands, they are abundant across the Andean landscape and are likely a key component in regional C cycling. Since efforts to quantify peatland distribution and C stocks across the tropical Andes have been limited due to the difficulty in sampling remote areas with very deep peat, there is a large knowledge gap in our quantification of the current C pools in the Andean mountains, which limits our ability to predict and monitor change from high rates of land use and climate change. In this paper we tested if ground‐penetrating radar (GPR), combined with manual coring and C analysis, could be used for estimating C stocks in peatlands of the Ecuadorian páramo. Our results indicated that GPR was successful in quantifying peat depths and carbon stocks. Detection of volcanic horizons like tephra layers allowed further refinement of variability of C stocks within the peat column, while providing information on the lateral extent of tephras at high (centimeter‐scale) resolution that may prove very useful for the correlation of time‐stratigraphic markers between sediments in alpine peatlands. In conclusion, this paper provides a methodological basis for quantifying C stocks in high‐altitude peatlands and to infer changes in the physical properties of soils that could be used as proxies for C content or paleoclimate reconstructions.
A single‐station empirical model for TEC over the Antarctic Peninsula using GPS‐TEC data
Authors: Feng Jiandi , Wang Zhengtao , Jiang Weiping , Zhao Zhenzhen , Zhang Bingbing
Published: January 2017

Compared with regional or global total electron content (TEC) empirical models, single‐station TEC empirical models may exhibit higher accuracy in describing TEC spatial and temporal variations for a single station. In this paper, a new single‐station empirical total electron content (TEC) model, called SSM‐month, for the O'Higgins Station in the Antarctic Peninsula is proposed by using Global Positioning System (GPS)‐TEC data from 01 January 2004 to 30 June 2015. The diurnal variation of TEC in the O'Higgins Station may have changing features in different months, sometimes even in opposite forms, because of ionospheric phenomena, such as the Mid‐latitude Summer Nighttime Anomaly (MSNA). To avoid the influence of different diurnal variations, the concept of monthly modeling is proposed in this study. The SSM‐month model, which is established by month (including 12 submodels that correspond to the 12 months), can effectively describe the diurnal variation of TEC in different months. Each submodel of the SSM‐month model exhibits good agreement with GPS‐TEC input data. Overall, the SSM‐month model fits the input data with a bias of 0.03 TECU (total electron content unit, 1 TECU = 1016 el m−2) and a standard deviation of 2.78 TECU. This model, which benefits from the modeling method, can effectively describe the MSNA phenomenon without implementing any modeling correction. TEC data derived from Center for Orbit Determination in Europe global ionosphere maps (CODE GIMs), International Reference Ionosphere 2012 (IRI2012), and NeQuick are compared with the SSM‐month model in the years of 2001 and 2015–2016. Result shows that the SSM‐month model exhibits good consistency with CODE GIMs, which is better than that of IRI2012 and NeQuick, in the O'Higgins Station on the test days.
Observability of ionospheric space‐time structure with ISR: A simulation study
Authors: Swoboda John , Semeter Joshua , Zettergren Matthew , Erickson Philip J.
Published: January 2017

The sources of error from electronically steerable array (ESA) incoherent scatter radar (ISR) systems are investigated both theoretically and with use of an open‐source ISR simulator, developed by the authors, called Simulator for ISR (SimISR). The main sources of error incorporated in the simulator include statistical uncertainty, which arises due to nature of the measurement mechanism and the inherent space‐time ambiguity from the sensor. SimISR can take a field of plasma parameters, parameterized by time and space, and create simulated ISR data at the scattered electric field (i.e., complex receiver voltage) level, subsequently processing these data to show possible reconstructions of the original parameter field. To demonstrate general utility, we show a number of simulation examples, with two cases using data from a self‐consistent multifluid transport model. Results highlight the significant influence of the forward model of the ISR process and the resulting statistical uncertainty on plasma parameter measurements and the core experiment design trade‐offs that must be made when planning observations. These conclusions further underscore the utility of this class of measurement simulator as a design tool for more optimal experiment design efforts using flexible ESA class ISR systems.
Historical space weather monitoring of prolonged aurora activities in Japan and in China
Authors: Kataoka Ryuho , Isobe Hiroaki , Hayakawa Hisashi , Tamazawa Harufumi , Kawamura Akito Davis , Miyahara Hiroko , Iwahashi Kiyomi , Yamamoto Kazuaki , Takei Masako , Terashima Tsuneyo , Suzuki Hidehiko , Fujiwara Yasunori , Nakamura Takuji
Published: January 2017

Great magnetic storms are recorded as aurora sightings in historical documents. The earliest known example of “prolonged” aurora sightings, with aurora persistent for two or more nights within a 7 day interval at low latitudes, in Japan was documented on 21–23 February 1204 in Meigetsuki, when a big sunspot was also recorded in China. We have searched for prolonged events over the 600 year interval since 620 in Japan based on the catalogue of Kanda [] and over the 700 year interval since 581 in China based on the catalogues of Tamazawa et al. (2017) and Hayakawa et al. (2015). Before the Meigetsuki event, a significant fraction of the 200 possible aurora sightings in Sòng dynasty (960–1279) of China was detected at least twice within a 7 day interval and sometimes recurred with approximately the solar rotation period of 27 days. The majority of prolonged aurora activity events occurred around the maximum phase of solar cycles rather than around the minimum, as estimated from the 14C analysis of tree rings. They were not reported during the Oort Minimum (1010–1050). We hypothesize that the prolonged aurora sightings are associated with great magnetic storms resulting from multiple coronal mass ejections from the same active region. The historical documents therefore provide useful information to support estimation of great magnetic storm frequency, which are often associated with power outages and other societal concerns.
Characterizing the spatial correlation of daily streamflows
Authors: Betterle A. , Schirmer M. , Botter G.
Published: January 2017

In this study we propose an analytical framework to estimate the spatial correlation of daily flows at two arbitrary locations within a given hydrologic district or river basin. The method builds on the description of the coupled streamflow dynamics at the outlet of two catchments, which are represented as correlated shot noises forced by Poisson rainfall. Novel analytical expressions for the spatial correlation of discharge are derived using a limited number of parameters that encapsulate effective precipitation regime and catchment drainage rates. The method is suited to describe how heterogeneity of climate and landscape features impact the spatial and temporal variability of flow regimes along river systems. The analysis suggests that frequency and intensity of synchronous effective rainfall events in the relevant contributing catchments are the main driver of the spatial correlation of daily discharge, unless the drainage rates of the two catchments differ by almost one order of magnitude. The method also portrays how the topological arrangement of the two outlets along the river network influences the underlying streamflow correlation and shows how nested catchments tend to maximize the spatial correlation of flow regimes. To demonstrate the potential of the tool, the model is tested on a set of 16 catchments belonging to a 120,000 km2region of the United States. The application evidences satisfactory performance in reproducing the observed spatial correlation of daily streamflows among the study sites (RMSE < 0.1). The approach provides a clue for the characterization of water availability in space at seasonal time scale, with implications for water resources assessment, risk prevention, and ecological studies.
Released for Public Comment: Space Weather Benchmarks and Operations‐to‐Research Plan
Authors: Jonas Seth , Murtagh William , Bonadonna Michael
Published: January 2017

The National Oceanic and Atmospheric Administration, on behalf of the National Science and Technology Council, published two notices in the Federal Register seeking public comment on draft products from the National Space Weather Action Plan: Space weather benchmarks and an operations‐to‐research plan.
Clustered assembly of Au nanoparticles from spherical diblock copolymer micelles encapsulating Au nanoparticle
Authors: Kim Jang Hwan , Zakia Maulida , Kim Joo Hyun , Park Seong Soo , Yoon Jinhwan , Huh PilHo , Yoo Seong II
Published: January 2017

Superstructures composed of diblock copolymer micelles and inorganic nanoparticles are quite interesting because the specific arrangement of inorganic nanoparticles within the micellar structure can reveal interesting opportunities in many field of science. In this perspective, we report a simple method to produce clustered assembly of Au nanoparticles in the micelles in attempt to induce plasmonic coupling among multiple Au nanoparticles in the assembled structures. Here, we utilized polystyrene‐block‐poly(acrylic acid), PS‐PAA, micelles containing single Au nanoparticle in the core (Au@PS‐PAA micelles) as building materials to initiate next‐level assembling process. In particular, the addition of HCl to the solution of Au@PS‐PAA micelles affected the overall equilibrium condition as well as kinetic process in the micellar solution. As a result, individual Au@PS‐PAA micelles could be merged together to form more large micelles with inclusion of multiple nanoparticles in the core, the process of which was accompanied with plasmonic coupling of Au nanoparticles. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44693.
Hydrogels based on copolymers of 2‐hydroxyethylmethacrylate and 2‐hydroxyethylacrylate as a delivery system for proteins: Interactions with lysozyme
Authors: Hackl Ellen V. , Khutoryanskiy Vitaliy V. , Ermolina Irina
Published: January 2017

Hydrogels have attracted considerable attention due to numerous applications, in particular as contact lenses and carriers for sustained drug delivery. The aim of the present work is to characterize the interactions of copolymer hydrogels consisted of 2‐hydroxyethylmethacrylate (HEMA) and 2‐hydroxyethylacrylate (HEA) with a small protein (lysozyme) and to assess the potential applications of these hydrogels as a drug delivery system for sustained release of protein‐based therapeutics. Physicochemical properties of protein‐loaded hydrogels, as well as lysozymein vitroloading and release and the conformation of the protein released from hydrogels were studied. The effect of copolymer composition on the protein deposition on hydrogels and protein aggregation in the presence of hydrogels was also assessed. The results show that introduction of HEA into the copolymeric hydrogels enhances their suitability as a delivery system for proteins. Copolymerisation of HEMA and HEA allows controlling the physicochemical properties of hydrogels and the protein release rate. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2017,134, 44768.
Poly(lactic acid)/poly(vinyl pyrrolidone) membranes produced by solution blow spinning: Structure, thermal, spectroscopic, and microbial barrier properties
Authors: Bonan Roberta F. , Bonan Paulo R. F. , Batista André U. D. , Perez Danyel E. C. , Castellano Lúcio R. C. , Oliveira Juliano E. , Medeiros Eliton S.
Published: January 2017

Submicrometric and nanometric poly(lactic acid)/poly(vinyl pyrrolidone) (PLA/PVP) fibrous membranes containing 0, 5, 10, 15, and 20 wt % PVP, with or without 20 wt % Copaiba oil (Copaifera sp.), were produced by solution blow spinning (SBS), using polymer injection rate of 120 μL min−1, gas pressure of 2.4 kPa, working distance of 20 cm, and collector rotation of 200 rpm. The morphological, thermal, and spectroscopic properties of these membranes were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetry (TG), and Fourier transform infrared spectroscopy (FTIR). A method for the evaluation of membrane microbial barrier properties based on resazurin colorimetric method was proposed. Results showed that the addition of both PVP and Copaiba oil produced thicker fibers; otherwise, there was no effect on morphology. Thermal analyses (TG and DSC) indicated the immiscible nature of polymer blends produced, also confirmed by the spectroscopic studies. Antimicrobial barrier properties were related to the antimicrobial effect of Copaiba oil, combined with it hydrophobic nature. The hydrophilic nature of PVP favored degradation of fiber mats, impairing barrier property when higher concentrations of PVP were added. Results indicate that produced spun mats can potentially be used in applications such as wound dressing. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44802.