bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple, Primary Brain Tumors with Diverse Origins and Different Localizations: Case Series and Review of the Literature
Authors: Tunthanathip Thara , Kanjanapradit Kanet , Ratanalert Sanguansin , Phuenpathom Nakornchai , Oearsakul Thakul , Kaewborisutsakul Anukoon
Published: August 2018

Background: Multiple, primary brain tumors with different histological types occurring in the same patient are extremely rare. Several hypotheses have been proposed, and the pathophysiology of coexisting tumors has long been debated; however, due to low incidence, standard practices for this scenario are still inconclusive. Case Description: The authors describe 6 cases of coexisting tumors. By conducting a literature research focused on the computed tomography (CT) era and patients without prior radiation or phakomatosis. Sixty-five such reported cases were identified. In addition, the authors summarize their experience in 6 patients including histopathological features, chronological presentations, outcomes, mortality, and management from their series as well as from previous cases from the reported literature. Conclusion: The coexistence of multiple, primary brain tumors is an interesting condition. Surgical management remains the major treatment; malignant histology has a poor prognostic factor.
Assessment of Sleep Quality among Medical Doctors in a Tertiary Hospital in a Semi-Rural Setting
Authors: Aliyu Ibrahim , Mohammed Ismail Inuwa , Lawal Taslim O. , Gudaji Mustapha , Garba Nuhu , Monsudi Kehinde Fasasi , Michael Godpower Chinedu , Peter Igoche David
Published: August 2018

Introduction: Sleep is an integral part of human physiology; therefore, disorders of sleep may result in significant derangement in human functionality. Sleep medicine has received little attention in Nigeria. Against this backdrop, this survey seeks to evaluate the quality of sleep among doctors. Methodology: This was a cross-sectional descriptive study involving 59 doctors working with Federal Medical Centre Birnin Kebbi, Kebbi State, Nigeria; it was done between August 2017 and December 2017. Purposive sampling method was adopted. The Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS) were adopted. The questionnaire was self-administered. Results: There were 34 (57.6%) males and 25 (42.4%) females. Their age ranged from 20 to 66 years, with a mean of 34.39 ± 8.00. The Epworth score ranged from 8 to 29, with a mean of 16.1 ± 4.4, while the PSQI score ranged from 5 to 19, with a mean of 9.5 ± 2.7. The mean work hour per week was 90.3 ± 36.2 h, and majority of the respondents worked for >80 h and or >24 h consecutively in the preceding week, and most had high ESS scores; however, this observation was not statistically significant (Fisher's exact test = 4.0904, P = 0.213). All respondents were poor sleepers and majority sleep for <7 h in the night. Respondents had worked for 5 years and less; house officers and medical offers had more tendencies for daytime sleepiness. Conclusion: All respondents were poor sleepers and also had prolonged work hours per week; there was also heightened daytime sleepiness.
Characterising Sobolev inequalities by controlled coarse homology and applications for hyperbolic spaces
Authors: Koivisto Juhani
Published: August 2018

We give a Sobolev inequality characterisation for the vanishing of the fundamental class in the controlled coarse homology of Nowak and Špakula for quasiconvex uniform spaces that support a local weak (1, 1)-Poincaré inequality. Among the applications, we consider visual Gromov hyperbolic spaces.
Lower bounds for codimension-1 measure in metric manifolds
Authors: Kinneberg Kyle
Published: August 2018

We establish Euclidean-type lower bounds for the codimen\-sion-1 Hausdorff measure of sets that separate points in doubling and linearly locally contractible metric manifolds. This gives a quantitative topological isoperimetric inequality in the setting of metric manifolds, in the sense that lower bounds for the codimension-1 measure of a set depend not on some notion of filling or volume but rather on in-radii of complementary components. As a consequence, we show that balls in a closed, connected, doubling, and linearly locally contractible metric

n

-manifold

(M,d)

with radius

0 < r \leq \mathrm {diam}(M)

have

n

-dimensional Hausdorff measure at least

c \cdot r^n

, where

c>0

depends only on

n

and on the doubling and linear local contractibility constants.
A Nash–Kuiper theorem for $C^{1,\frac{1}{5}-\delta}$ immersions of surfaces in 3 dimensions
Authors: De Lellis Camillo , Inauen Dominik , Székelyhidi Jr. László
Published: August 2018

We prove that, given a

C^2

Riemannian metric

g

on the 2-dimensional disk

D_2

, any short

C^1

immersion of

(D_2,g)

into

\mathbb R^3

can be uniformly approximated with

C^{1,\alpha}

isometric immersions for any

\alpha < \frac{1}{5}

. This statement improves previous results by Yu. F. Borisov and of a joint paper of the first and third author with S. Conti.
Connectivity of Julia sets of Newton maps: a unified approach
Authors: Barański Krzysztof , Fagella Núria , Jarque Xavier , Karpińska Bogusława
Published: August 2018

In this paper we present a unified proof of the fact that the Julia set of Newton’s method applied to a holomorphic function on the complex plane (a polynomial of degree larger than 1 or a transcendental entire function) is connected. The result was recently completed by the authors’ previous work, as a consequence of a more general theorem whose proof spreads among many papers, which consider separately a number of particular cases for rational and transcendental maps, and use a variety of techniques. In this note we present a unified, direct and reasonably self-contained proof which works in all situations alike.
Boundedness of spectral multipliers for Schrödinger operators on open sets
Authors: Iwabuchi Tsukasa , Matsuyama Tokio , Taniguchi Koichi
Published: August 2018

Let

H_V

be a self-adjoint extension of the Schrödinger operator

-\Delta+V(x)

with the Dirichlet boundary condition on an arbitrary open set

\Omega

of

\mathbb R^d

, where

d \ge 1

and the negative part of potential

V

belongs to the Kato class on

\Omega

. The purpose of this paper is to prove

L^p

-

L^q

-estimates and gradient estimates for an operator

\varphi(H_V)

, where

\varphi

is an arbitrary rapidly decreasing function on

\mathbb{R}

, and

\varphi(H_V)

is defined via the spectral theorem.
Structure of tangencies to distributions via the implicit function theorem
Authors: Delladio Silvano
Published: August 2018

We investigate the structure and the dimension of the tangency set to a

C^1

smooth distribution of

n

-dimensional vector subspaces of

\mathbb R^{n+m}

, by an argument based on the implicit function theorem.
Ортогональные по Соболеву полиномы, порожденные полиномами Якоби и Лежандра, и специальные ряды со свойством прилипания их частичных сумм
Authors: Sharapudinov Idris Idrisovich
Published: August 2018

Для произвольного натурального $r$ рассмотрены полиномы $p^{\alpha,\beta}_{r,k}(x)$, $k=0,1,…$, ортонормированные относительно скалярного произведения типа Соболева вида
$$
\langle f,g\rangle =\sum_{\nu=0}^{r-1}f^{(\nu)}(-1)g^{(\nu)}(-1)+
\int_{-1}^{1}f^{(r)}(t)g^{(r)}(t)(1-t)^\alpha(1+t)^\beta dt
$$
и изучены их свойства. Введены в рассмотрение ряды Фурье по полиномам $p_{r,k}(x)=p^{0,0}_{r,k}(x)$ и некоторые их обобщения, частичные суммы которых сохраняют некоторые важные свойства частичных сумм ряда Фурье по полиномам $p_{r,k}(x)$, в том числе и свойство $r$-кратного совпадения (прилипания) частичных сумм ряда Фурье по полиномам $p_{r,k}(x)$ в точках $-1$ и $1$ между собой и с исходной функцией $f(x)$. Основное внимание уделено исследованию вопросов приближения гладких и аналитических функций частичными суммами упомянутых обобщений, представляющих собой специальные ряды по ультрасферическим полиномам Якоби со свойством прилипания их частичных сумм в точках $-1$ и $1$.
Библиография: 31 название.
Тропический предел логарифмических точек перегиба
Authors: Mikhalkin Grigory Borisovich , Renaudineau Arthur
Published: August 2018

Описывается поведение логарифмических точек перегиба плоских кривых (т.е. точек перегиба по отношению к параллелизации на $(\mathbb{C}^\times)^2$, заданной покоординатным умножением) при переходе к тропическому пределу. В предположении гладкости предельной тропической кривой показано, что логарифмические точки перегиба попарно стремятся к серединам конечных ребер тропической плоской кривой.
Библиография: 11 названий.
LACK OF PREDICTION OF MEFLOQUINE AND MEFLOQUINE-ARTESUNATE TREATMENT OUTCOME BY MUTATIONS IN THE PLASMODIUM FALCIPARUM MULTIDRUG RESISTANCE 1 (PFMDR1) GENE FOR PLASMODIUM FALCIPARUM MALARIA IN PERU
Authors: PILLAI DYLAN R. , HIJAR GISELY , MONTOYA YSABEL , MARQUIÑO WILMER , RUEBUSH TRENTON K. , WONGSRICHANALAI CHANSUDA , KAIN KEVIN C.
Published: August 2018

We assessed whether mutations in the Plasmodium falciparum multidrug-resistance gene 1 (pfmdr1) (C1034S, D1042N, and Y1246D) would predict treatment outcome during a 28-day in vivo treatment trial in the Peruvian Amazon. Mefloquine (MQ) was compared with mefloquine-artesunate (MQ-AS) in a randomized, multi-clinic protocol for the first time in the Americas. Of 115 patients enrolled in the in vivo arm, 97 patients were eligible for molecular analysis. All 97 patients remained parasite-free during 28 days of follow-up (MQ, n = 46; MQ-AS, n = 51), indicating 100% clinical efficacy of the MQ and MQ-AS treatment regimens. The reported MQ-sensitive alleles (C1034, D1042, and Y1246) were present in 48.5% (n = 47) of the cases, whereas 49 isolates (50.5%) contained the D1246 mutation reported to confer MQ resistance in vitro. However, neither this mutation nor a double mutation (S1034, D1246; n = 16) was predictive of MQ treatment outcome.
SHORT REPORT: ECHINOCOCCUS GRANULOSUS FROM XINJIANG, PR CHINA: cDNAS ENCODING THE EG95 VACCINE ANTIGEN ARE EXPRESSED IN DIFFERENT LIFE CYCLE STAGES AND ARE CONSERVED IN THE ONCOSPHERE
Authors: ZHANG WENBAO , LI JUN , YOU HONG , ZHANG ZHUANGZHI , TURSON GULINUL , LOUKAS ALEX , MCMANUS DONALD P.
Published: August 2018

The EG95-based vaccine protects sheep from infection with the dog tapeworm Echinococcus granulosus. The EG95 encoding gene is a member of a multigene family, several members of which are expressed in the oncosphere, believed to be the target of immunity induced by the vaccine. E. granulosus exhibits extensive intraspecific (strain) variation, and variability of the eg95 gene in different isolates of E. granulosus may directly impact the effectiveness of the EG95-based vaccine. We analyzed the eg95 gene from E. granulosus collected in Xinjiang, in northwest China, where hydatid disease is hyperendemic. The gene is expressed in oncospheres, protoscoleces, and immature and mature adult worms, and the eg95 gene family was shown to comprise two basic sequence types. Very limited sequence variation was evident in the EG95 protein from oncospheres. This high degree of sequence conservation predicts that the vaccine will continue to be effective in China and elsewhere.
CASE REPORT: OPHTHALMOMYIASIS EXTERNA IN DALLAS COUNTY, TEXAS
Authors: SIGAUKE ELLEN , BEEBE WALTER E. , GANDER RITA M. , CAVUOTI DOMINICK , SOUTHERN PAUL M.
Published: August 2018

Ophthalmomyiasis externa is an uncommon condition in North America. If not recognized and managed accordingly, it can be complicated by the potentially fatal condition ophthalmomyiasis interna. Ophthalmomyiasis externa is mainly caused by the sheep bot fly Oestrus ovis; thus, it is more common in farming communities. We report a case of ophthalmomyiasis externa in a young woman from Dallas County, Texas, who had no known history of contact with farm animals.
INCREASED APOPTOSIS AND EXPRESSION OF TUMOR NECROSIS FACTOR-α CAUSED BY INFECTION OF CULTURED HUMAN MONOCYTES WITH DENGUE VIRUS
Authors: ESPINA LUZ M. , VALERO NEREIDA J. , HERNÁNDEZ JANETH M. , MOSQUERA JESÚS A.
Published: August 2018

Dengue (DEN) virus is responsible for one of the most significant viral diseases in tropical countries. Monocytes/macrophages (Mo/Mϕ) are the major target cells for DEN virus. To determine the effects of the interaction between DEN virus and Mo/Mϕ, human monocyte cultures were infected with DEN virus type 2. Apoptosis and production of tumor necrosis factor-α (TNF-α) and nitric oxide were measured in control and infected cultures. Virus was taken up by phagocytosis, but no membrane-coated pits at the virus attachment sites were observed. Increased number of apoptotic cells and increased production of TNF-α were observed in infected monocyte cultures. No increase in production of nitric oxide was observed. These results may be related to early primary viral infection, in which virus could induce apoptosis in monocytes, but monocytes may contribute to host defense mechanisms against virus by viral phagocytosis, phagocytosis of infected apoptotic cells, and the release of proinflammatory cytokines.
Multi-Dimensional Thermal Properties of Insulated Heat Shield Material Systems
Authors:   Materials, Processes and Parts Council
Published: August 2018

This test method measures the system material properties of an insulated formed heat shield under in-vehicle conditions. While the material properties of the individual components can often be determined via existing test methods, the system properties of the entire composite is typically much harder to ascertain (especially for multi-layer shields). System material properties include thermal conductivity in the lateral or in-plane (x) direction, thermal conductivity through the thickness or perpendicular (y), surface emissivity on the top and bottom sides of the shield and specific heat of the shield material.
Mercury distribution in the upper troposphere and lowermost stratosphere according to measurements by the IAGOS-CARIBIC observatory: 2014–2016
Authors: Slemr Franz , Weigelt Andreas , Ebinghaus Ralf , Bieser Johannes , Brenninkmeijer Carl A. M. , Rauthe-Schöch Armin , Hermann Markus , Martinsson Bengt G. , van Velthoven Peter , Bönisch Harald , Neumaier Marco , Zahn Andreas , Ziereis Helmut
Published: August 2018

Abstract. Mercury was measured onboard the IAGOS-CARIBIC passenger aircraft from May 2005 until February 2016 during near monthly sequences of mostly four intercontinental flights from Germany to destinations in North and South America, Africa and South and East Asia. Most of these mercury data were obtained using an internal default signal integration procedure of the Tekran instrument but since April 2014 more precise and accurate data were obtained using post-flight manual integration of the instrument raw signal. In this paper we use the latter data.Increased upper tropospheric total mercury (TM) concentrations due to large scale biomass burning were observed in the upper troposphere (UT) at the equator and southern latitudes during the flights to Latin America and South Africa in boreal autumn (SON) and boreal winter (DJF). TM concentrations in the lowermost stratosphere (LMS) decrease with altitude above the thermal tropopause but the gradient is less steep than reported before. Seasonal variation of the vertical TM distribution in the UT and LMS is similar to that of other trace gases with surface sources and stratospheric sinks. Speciation experiments suggest comparable TM and gaseous elementary mercury (GEM) concentrations at and below the tropopause leaving little space for Hg2+ (TM − GEM) being the dominating component of TM here. In the stratosphere significant GEM concentrations were found to exist up to 4 km altitude above the thermal tropopause. Correlations with N2O as a reference tracer suggest stratospheric lifetimes of 72±37 and 74±27 years for TM and GEM, respectively, comparable to the stratospheric lifetime of COS. This coincidence, combined with pieces of evidence from us and other researchers, corroborates the hypothesis that Hg2+ formed by oxidation in the stratosphere attaches to sulfate particles formed mainly by oxidation of COS and is removed with them from the stratosphere by air mass exchange, gravitational sedimentation and cloud scavenging processes.
Historical black carbon deposition in the Canadian High Arctic: a >250-year long ice-core record from Devon Island
Authors: Zdanowicz Christian M. , Proemse Bernadette C. , Edwards Ross , Feiteng Wang , Hogan Chad M. , Kinnard Christophe , Fisher David
Published: August 2018

Abstract. Black carbon aerosol (BC), which is emitted from natural and anthropogenic sources (e.g., wildfires, coal burning), can contribute to magnify climate warming at high latitudes by darkening snow- and ice-covered surfaces, and subsequently lowering their albedo. Therefore, modeling the atmospheric transport and deposition of BC to the Arctic is important, and historical archives of BC accumulation in polar ice can help to validate such modeling efforts. Here we present a > 250-year ice-core record of refractory BC (rBC) deposition on Devon ice cap, Canada, spanning the years from 1735 to 1992. This is the first such record ever developed from the Canadian Arctic. The estimated mean deposition flux of rBC on Devon ice cap for 1963–1990 is 0.2 mg m−2 a−1, which is at the low end of estimates from Greenland ice cores obtained using the same analytical method ( ∼ 0.1–4 mg m−2 a−1). The Devon ice cap rBC record also differs from the Greenland records in that it shows only a modest increase in rBC deposition during the 20th century. In the Greenland records a pronounced rise in rBC is observed from the 1880s to the 1910s, which is largely attributed to midlatitude coal burning emissions. The deposition of contaminants such as sulfate and lead increased on Devon ice cap in the 20th century but no concomitant rise in rBC is recorded in the ice. Part of the difference with Greenland could be due to local factors such as melt–freeze cycles on Devon ice cap that may limit the detection sensitivity of rBC analyses in melt-impacted core samples, and wind scouring of winter snow at the coring site. Air back-trajectory analyses also suggest that Devon ice cap receives BC from more distant North American and Eurasian sources than Greenland, and aerosol mixing and removal during long-range transport over the Arctic Ocean likely masks some of the specific BC source–receptor relationships. Findings from this study suggest that there could be a large variability in BC aerosol deposition across the Arctic region arising from different transport patterns. This variability needs to be accounted for when estimating the large-scale albedo lowering effect of BC deposition on Arctic snow/ice.
Towards a satellite – in situ hybrid estimate for organic aerosol abundance
Authors: Liao Jin , Hanisco Thomas F. , Wolfe Glenn M. , St. Clair Jason , Jimenez Jose L. , Campuzano-Jost Pedro , Nault Benjamin A. , Fried Alan , Marais Eloise A. , Gonzalez Abad Gonzalo , Chance Kelly , Jethva Hiren T. , Ryerson Thomas B. , Warneke Carsten , Wisthaler Armin
Published: August 2018

Abstract. Organic aerosol (OA) is one of the main components of the global particulate burden and intimately links natural and anthropogenic emissions with air quality and climate. It is challenging to accurately represent OA in global models. Direct quantification of global OA abundance is not possible with current remote sensing technology; however, it may be possible to exploit correlations of OA with remotely observable quantities to infer OA spatiotemporal variability. In particular, formaldehyde (HCHO) and OA share common sources via both primary emissions and secondary production from oxidation of volatile organic compounds (VOCs). We examine OA-HCHO correlations using data from summer-time airborne campaigns investigating biogenic (NASA SEAC4RS and DC3), biomass burning (NASA SEAC4RS) and anthropogenic conditions (NOAA CalNex and NASA KORUS-AQ). In situ OA correlates well with HCHO (r = 0.59–0.97) but the slope and intercept of this relationship vary with chemical regime. For biogenic and anthropogenic regions, the OA-vs-HCHO slope is higher in low NOx conditions, where HCHO yields are lower and aerosol yields are likely higher. The OA-vs-HCHO slope of wild fires is more than 9 times higher than that associated with biogenic and anthropogenic sources. An estimate of near-surface OA is derived by combining observed in situ relationships with HCHO column retrievals from NASA’s Ozone Monitoring Instrument (OMI). We evaluate this OA estimate against OA observations from the US EPA IMPROVE network and simulated OA from the GEOS-Chem global chemical transport model. The OA estimate compares well with IMPROVE data obtained over summer months (e.g. slope = 0.62, r = 0.56 for August 2013), comparable to intensively validated GEOS-Chem performance (e.g. slope = 0.57, r = 0.56) and superior to the correlation with satellite-derived total aerosol extinction (r = 0.41). Improving the detection limit of satellite HCHO and expanding in situ airborne HCHO and OA coverage in future missions will improve the quality and spatiotemporal coverage of this OA estimate, potentially enabling constraints on the global OA distribution.
Evaluation of random forests and Prophet for daily streamflow forecasting
Authors: Papacharalampous Georgia A. , Tyralis Hristos
Published: August 2018

Abstract. We assess the performance of random forests and Prophet in
forecasting daily streamflow up to seven days ahead in a river in the US.
Both the assessed forecasting methods use past streamflow observations, while
random forests additionally use past precipitation information. For
benchmarking purposes we also implement a naïve method based on the
previous streamflow observation, as well as a multiple linear regression
model utilizing the same information as random forests. Our aim is to
illustrate important points about the forecasting methods when implemented
for the examined problem. Therefore, the assessment is made in detail at a
sufficient number of starting points and for several forecast horizons. The
results suggest that random forests perform better in general terms, while
Prophet outperforms the naïve method for forecast horizons longer than
three days. Finally, random forests forecast the abrupt streamflow
fluctuations more satisfactorily than the three other methods.
The influence of humidity on the performance of a low-cost air particle mass sensor and the effect of atmospheric fog
Authors: Jayaratne Rohan , Liu Xiaoting , Thai Phong , Dunbabin Matthew , Morawska Lidia
Published: August 2018

Abstract. While low-cost particle sensors are increasingly being
used in numerous applications, most of them have no heater or dryer at the
inlet to remove water from the sample before measurement. Deliquescent
growth of particles and the formation of fog droplets in the atmosphere can
lead to significant increases in particle number concentration (PNC) and
mass concentrations reported by such sensors. We carried out a detailed
study using a Plantower PMS1003 low-cost particle sensor, both in the
laboratory and under actual ambient field conditions, to investigate its
response to increasing humidity and the presence of fog in the air. We found
significant increases in particle number and mass concentrations at relative
humidity above about 75 %. During a period of fog, the total PNC increased
by 28 %, while the PNC larger than 2.5 µm increased by over 50 %.
The PM10 concentration reported by the PMS1003 was 46 % greater than
that on the standard monitor with a charcoal dryer at the inlet. While there
is a causal link between particle pollution and adverse health effects, the
presence of water on the particles is not harmful to humans. Therefore, air
quality standards for particles are specifically limited to solid particles
and standard particle monitoring instruments are fitted with a heater or
dryer at the inlet to remove all liquid material from the sample before the
concentrations are measured. This study shows that it is important to
understand that the results provided by low-cost particle sensors, such as
the PMS1003, cannot be used to ascertain if air quality standards are being
met.
Retrieving horizontally resolved wind fields using multi-static meteor radar observations
Authors: Stober Gunter , Chau Jorge L. , Vierinen Juha , Jacobi Christoph , Wilhelm Sven
Published: August 2018

Abstract. Recently, the MMARIA (Multi-static, Multi-frequency Agile Radar for
Investigations of the Atmosphere) concept of a multi-static VHF meteor radar
network to derive horizontally resolved wind fields in the mesosphere–lower
thermosphere was introduced. Here we present preliminary results of the
MMARIA network above Eastern Germany using two transmitters located at
Juliusruh and Collm, and five receiving links: two monostatic and three
multi-static. The observations are complemented during a one-week campaign,
with a couple of addition continuous-wave coded transmitters, making a total
of seven multi-static links. In order to access the kinematic properties of
non-homogenous wind fields, we developed a wind retrieval algorithm that
applies regularization to determine the non-linear wind field in the altitude
range of 82–98 km. The potential of such observations and the new retrieval
to investigate gravity waves with horizontal scales between 50–200 km is
presented and discussed. In particular, it is demonstrated that horizonal
wavelength spectra of gravity waves can be obtained from the new data set.
Radiometric correction of observations from
microwave humidity sounders
Authors: Moradi Isaac , Beauchamp Jim , Ferraro Ralph
Published: August 2018

Abstract. Advanced Microwave Sounding Unit (AMSU-B) and Microwave Humidity Sounder (MHS) are total power microwave radiometers operating at frequencies near the water vapor absorption line at 183 GHz. The measurements of these instruments are crucial for deriving a variety of climate and hydrological products such as water vapor, precipitation, and ice cloud parameters. However these measurements are subject to several errors that can be classified into radiometric and geometric errors. The aim of this study is to quantify and correct the radiometric errors in these observations through intercalibration. Since bias in the calibration of microwave instruments changes with scene temperature, a two-point intercalibration correction scheme was developed based on averages of measurements over the tropical oceans and night-time polar regions. The intercalibration coefficients were calculated on a monthly basis using measurements averaged over each specified region and each orbit, then interpolated to estimate the daily coefficients. Since AMSU-B and MHS channels operate at different frequencies and polarizations, the measurements from the two instruments were not interalibrated. Because of the negligible diurnal cycle of both temperature and humidity fields over the tropical oceans, the satellites with most stable time series of brightness temperatures over the tropical oceans (NOAA-17 for AMSU-B and NOAA-18 for MHS) were selected as the reference satellites and other similar instruments were intercalibrated with respect to the reference instrument. The results show that Channels 1, 3, 4, and 5 of AMSU-B onboard NOAA-16 and Channels 1 and 4 of AMSU-B onboard NOAA-15 show a large drift over the period of operation. The MHS measurements from instruments onboard NOAA-18, NOAA-19, and MetOp-A are generally consistent with each other. Because of the lack of reference measurements, radiometric correction of microwave instruments remain a challenge as the intercalibration of these instruments largely depend on the stability of the reference instrument.
Mesoscale contribution to the long-range offshore transport of organic carbon from the Canary Upwelling System to the open North Atlantic
Authors: Lovecchio Elisa , Gruber Nicolas , Münnich Matthias
Published: August 2018

Abstract. Several studies in upwelling regions have suggested that mesoscale structures, such as eddies and filaments, contribute substantially to the long-range transport of the organic carbon from the nearshore region of production to the offshore region of remineralization. Yet a comprehensive analysis of this mesoscale flux and of its impact across the Canary Upwelling System (CanUS) has not been provided. Here, we fill this gap using simulations with the Regional Oceanic Modeling System (ROMS) coupled to a Nutrient, Phytoplankton, Zooplankton and Detritus (NPZD) ecosystem model. We run climatological simulations on an Atlantic telescopic grid with an eddy-resolving resolution in the CanUS. Using both a Reynolds flux decomposition and structure-identification algorithms, we quantify and characterize the organic carbon fluxes driven by filaments and eddies within the upper 100 m and put them in relationship to the total offshore transport. Our analysis reveals that both coastal filaments and eddies enhance the offshore flux of organic carbon, but that their contribution is very different. Upwelling filaments, with their high speeds and high concentrations, transport the organic carbon offshore in a very intense, but coastally confined manner, contributing nearly 80 % to the total flux of organic carbon at 100 km offshore. The filament contribution tapers off quickly to near zero values at 1000 km off the coast, leading to a strong offshore flux divergence that is the main lateral source of organic carbon in the coastal waters up to 1000 km offshore. Some of this divergence is also due to the filaments inducing a substantial vertical subduction of the organic carbon below 100 m. Owing to the temporal persistence and spatial recurrence of filaments, the filament transport largely constitutes a time-mean flux, while the time-varying component, i.e., the turbulent flux, is comparatively small. At distances beyond 500 km from the coast, eddies dominate the mesoscale offshore transport. Although their contribution represents only 20 % of the total offshore flux and its divergence, eddies, especially cyclones, transport organic carbon offshore to distances as great as 2000 km from the coast. The eddy transport largely represents a turbulent flux, but striations in this transport highlight the existence of typical formation spots and recurrent offshore propagation pathways. While they propagate slowly, eddies are an important organic carbon reservoir for the open waters, as they contain, on average, a third of the organic carbon in this region, two thirds of which is found in cyclones. Our analysis confirms the importance of mesoscale processes for the offshore organic carbon transport and the fueling of the heterotrophic activity in the eastern subtropical North Atlantic, and highlights the need to consider the mesoscale flux in order to fully resolve the three-dimensionality of the marine organic carbon cycle.
Causes of simulated long-term changes in phytoplankton biomass in the Baltic proper: a wavelet analysis
Authors: Hieronymus Jenny , Eilola Kari , Hieronymus Magnus , Meier H. E. Markus , Saraiva Sofia , Karlson Bengt
Published: August 2018

Abstract. The co-variation of key variables with simulated phytoplankton biomass in the
Baltic proper has been examined using wavelet analysis and results of a
long-term simulation for 1850–2008 with a high-resolution coupled
physical–biogeochemical circulation model for the Baltic Sea. By focusing on
inter-annual variations, it is possible to track effects acting on decadal
timescales such as temperature increase due to climate change as well as
changes in nutrient input. The strongest inter-annual coherence indicates
that variations in phytoplankton biomass are determined by changes in
concentrations of the limiting nutrient. However, after 1950 high nutrient
concentrations created a less-nutrient-limited regime, and the coherence was
reduced. Furthermore, the inter-annual coherence of mixed-layer nitrate with
riverine input of nitrate is much larger than the coherence between mixed-layer
phosphate and phosphate loads. This indicates a greater relative
importance of the vertical flux of phosphate from the deep layer into the
mixed layer. In addition, shifts in nutrient patterns give rise to changes in
phytoplankton nutrient limitation. The modelled pattern shifts from purely
phosphate limited to a seasonally varying regime. The results further
indicate some effect of inter-annual temperature increase on cyanobacteria
and flagellates. Changes in mixed-layer depth affect mainly diatoms due to
their high sinking velocity, while inter-annual coherence between irradiance
and phytoplankton biomass is not found.
Portable multi- and many-core performance for finite-difference or finite-element codes – application to the free-surface component of NEMO (NEMOLite2D 1.0)
Authors: Porter Andrew R. , Appleyard Jeremy , Ashworth Mike , Ford Rupert W. , Holt Jason , Liu Hedong , Riley Graham D.
Published: August 2018

Abstract. We present an approach which we call PSyKAl that is designed to achieve
portable performance for parallel finite-difference, finite-volume, and finite-element
earth-system models.
In PSyKAl the code related to the underlying science is
formally separated from code related to parallelization and single-core
optimizations. This separation of concerns allows scientists to code their
science independently of the underlying hardware architecture and for
optimization specialists to be able to tailor the code for a particular
machine, independently of the science code. We have taken the free-surface
part of the NEMO ocean model and created a new shallow-water model named
NEMOLite2D. In doing this we have a code which is of a manageable size and
yet which incorporates elements of full ocean models (input/output, boundary
conditions, etc.). We have then manually constructed a PSyKAl version of this
code and investigated the transformations that must be applied to the
middle, PSy, layer in order to achieve good performance, both serial and
parallel. We have produced versions of the PSy layer parallelized with both
OpenMP and OpenACC; in both cases we were able to leave the natural-science
parts of the code unchanged while achieving good performance on both
multi-core CPUs and GPUs. In quantifying whether or not the obtained
performance is “good” we also consider the limitations of the basic roofline
model and improve on it by generating kernel-specific CPU ceilings.
Global joint assimilation of GRACE and SMOS for improved estimation of root-zone soil moisture and vegetation response
Authors: Tian Siyuan , Renzullo Luigi J. , van Dijk Albert I. J. M. , Tregoning Paul , Walker Jeffrey P.
Published: August 2018

Abstract. The lack of direct measurement of root-zone soil moisture poses a challenge to the large-scale prediction of ecosystem response to variation in soil water. Microwave remote sensing capability is limited to measuring moisture content in the uppermost few centimetres of soil. In contrast, GRACE (Gravity Recovery and Climate Experiment) mission detected the variability in storage within the total water column, which is often dominated by groundwater variation. However, not all vegetation communities can access groundwater. In this study, satellite-derived water content from GRACE and SMOS were jointly assimilated into an ecohydrological model to better predict the impact of changes in root-zone soil moisture on vegetation vigour. Overall, the accuracy of root-zone soil moisture prediction though the joint assimilation of surface soil moisture and total water storage retrievals showed improved consistency with ground-based soil moisture measurements and satellite-observed greenness when compared to open-loop estimates (i.e. without assimilation). For example, the correlation between modelled and in-situ measurements of root-zone moisture increased by 0.1 on average over grasslands and croplands. Improved correlations were found between vegetation greenness and soil water storage derived from the joint assimilation with an increase up to 0.47 over grassland compared to open-loop estimates. Joint assimilation results show a more severe deficit in soil water in eastern Australia, western North America and eastern Brazil over the period of 2010 to 2015 than the open-loop, consistent with the satellite-observed vegetation greenness. The assimilation of satellite-observed water content contributes to more accurate knowledge of soil water availability, providing new insights for monitoring hidden water stress and vegetation response.
Exploring the merging of the global land evaporation WACMOS-ET products based on local tower measurements
Authors: Jiménez Carlos , Martens Brecht , Miralles Diego M. , Fisher Joshua B. , Beck Hylke E. , Fernández-Prieto Diego
Published: August 2018

Abstract. An inverse error variance weighting of the anomalies of three terrestrial evaporation (ET) products from the WACMOS-ET project based on FLUXNET sites is presented. The three ET models were run daily and at a resolution of 25 km for 2002–2007, and based on common input data when possible. The local weights, derived based on the variance of the difference between the tower ET anomalies and the modelled ET anomalies, were made dynamic by estimating them using a 61-day running window centred on each day. These were then extrapolated from the tower locations to the global landscape by regressing them on the main model inputs and derived ET using a neural network. Over the stations, the weighted scheme usefully decreased the random error component, and the weighted ET correlated better with the tower data than a simple average. The global extrapolation produced weights displaying strong seasonal and geographical patterns, which translated into spatiotemporal differences between the ET weighted and simple average ET products. However, the uncertainty of the weights after the extrapolation remained large. Out-sample prediction tests showed that the tower data set, mostly located at temperate regions, had limitations with respect to the representation of different biome and climate conditions. Therefore, even if the local weighting was successful, the extrapolation to a global scale remains problematic, showing a limited added value over the simple average. Overall, this study suggests that merging tower observations and ET products at the timescales and spatial scales of this study is complicated by the tower spatial representativeness, the products' coarse spatial resolution, the nature of the error in both towers and gridded data sets, and how all these factors impact the weights extrapolation from the tower locations to the global landscape.
Estimating network related risks: A methodology and an application in the transport sector
Authors: Hackl Jürgen , Lam Juan Carlos , Heitzler Magnus , Adey Bryan T. , Hurni Lorenz
Published: August 2018

Abstract. Networks such as
transportation, water, and power are critical lifelines for society. Managers
plan and execute interventions to guarantee the operational state of their
networks under various circumstances, including after the occurrence of
(natural) hazard events. Creating an intervention program demands knowing the
probable direct and indirect consequences (i.e., risk) of the various hazard
events that could occur in order to be able to mitigate their effects. This paper
introduces a methodology to support network managers in the quantification of
the risk related to their networks. The methodology is centered on the
integration of the spatial and temporal attributes of the events that need to
be modeled to estimate the risk. Furthermore, the methodology supports the
inclusion of the uncertainty of these events and the propagation of these
uncertainties throughout the risk modeling. The methodology is implemented
through a modular simulation engine that supports the updating and swapping
of models according to the needs of network managers. This work demonstrates
the usefulness of the methodology and simulation engine through an
application to estimate the potential impact of floods and mudflows on a road
network located in Switzerland. The application includes the modeling of
(i) multiple time-varying hazard events; (ii) their physical and functional
effects on network objects (i.e., bridges and road sections); (iii) the
functional interrelationships of the affected objects; (iv) the resulting
probable consequences in terms of expected costs of restoration, cost of
traffic changes, and duration of network disruption; and (v) the restoration
of the network.
Landsliding near Enguri dam (Caucasus, Georgia) and possible seismotectonic effects
Authors: Tibaldi Alessandro , Oppizzi Paolo , Gierke John , Oommen Thomas , Tsereteli Nino , Odilavadze Davit
Published: August 2018

Abstract. The Enguri dam and water reservoir, nested in southwestern Caucasus (Republic of Georgia), are surrounded by steep mountain slopes. At a distance of 2.5 km from the dam, a mountain ridge along the reservoir is affected by active deformations with a double vergence. The western slope, directly facing the reservoir, has deformations that involve a subaerial area of 1.2 km2. The head scarp interests the main Jvari–Khaishi–Mestia road with offset of man-made features that indicate slip rates of 2–9 cm/y. Static, pseudostatic and Newmark numerical analyses, based on field and seismological data, suggest different unstable rock volumes basing on the environment conditions. An important effect of variation of water table is showed, as well as the possible destabilization of the landslide following seismic shaking compatible with the expected local Peak Ground Acceleration. This worst scenario corresponds to an unstable volume in the order of up to 48 ± 12 * 106 m3. The opposite, eastern slope of the same mountain ridge is also affected by wide deformation involving an area of 0.37 km2. Here, field data indicate 2–5 cm/y of short-term and long-term slip rates. Ground Penetrating Radar surveys of the head scarps confirm that these slip planes are steep and extend downward. All these evidences are interpreted as resulting from two similar landslides, whose possible causes are discussed, comprising seismic triggering, mountain rapid uplift, river erosion and lake variations.
Overflow of cold water across the Iceland–Faroe Ridge through the Western Valley
Authors: Hansen Bogi , Larsen Karin Margretha Húsgarð , Olsen Steffen Malskær , Quadfasel Detlef , Jochumsen Kerstin , Østerhus Svein
Published: August 2018

Abstract. The Iceland–Faroe Ridge (IFR) is considered to be the
third most important passage for dense overflow water from the Nordic Seas
feeding into the lower limb of the Atlantic Meridional Overturning
Circulation with a volume transport on the order of 1 Sv (106 m3 s−1).
The Western Valley, which is the northernmost deep passage across
the IFR, has been presumed to supply a strong and persistent overflow
(WV-overflow), contributing a large fraction of the total overflow across
the IFR. However, prolonged measurements of this transport are so far
missing. In order to quantify the flow by direct measurements, three
instrumental packages were deployed close to the sill of the Western Valley
for 278 days (2016–2017) including an acoustic Doppler current profiler at
the expected location of the overflow core. The average volume transport of
WV-overflow during this field experiment was found to be (0.02±0.05)
Sv. Aided by the observations and a two-layer hydraulic model, we argue that
the reason for this low value is the inflow of warm Atlantic water to the
Norwegian Sea in the upper layers suppressing the deep overflow. The link
between deep and surface flows explains an observed relationship between
overflow and sea level slope as measured by satellite altimetry. This
relationship, combined with historical hydrographic measurements, allows us
to conclude that the volume transport of WV-overflow most likely has been
less than 0.1 Sv on average since the beginning of regular satellite
altimetry in 1993. Our new direct measurements do not allow us to present an
updated estimate of the total overflow across the IFR, but they indicate
that it may well be considerably less than 1 Sv.
What are the prospects for seasonal prediction of the marine environment of the North-west European Shelf?
Authors: Tinker Jonathan , Krijnen Justin , Wood Richard , Barciela Rosa , Dye Stephen R.
Published: August 2018

Abstract. Sustainable management and utilisation of the North-west European Shelf (NWS) seas
could benefit from reliable forecasts of the marine environment on
monthly to seasonal timescales. Recent advances in global seasonal forecast
systems and regional marine reanalyses for the NWS allow us to investigate
the potential for seasonal forecasts of the state of the NWS. We identify three possible approaches to address this issue: (A) basing NWS
seasonal forecasts directly on output from the Met Office's GloSea5 global
seasonal forecast system; (B) developing empirical downscaling relationships
between large-scale climate drivers predicted by GloSea5 and the state of
the NWS; and (C) dynamically downscaling GloSea5 using a regional model. We
show that the GloSea5 system can be inadequate for simulating the NWS
directly (approach A). We explore empirical relationships between the winter
North Atlantic Oscillation (NAO) and NWS variables estimated using a
regional reanalysis (approach B). We find some statistically significant
relationships and present a skillful prototype seasonal forecast for English
Channel sea surface temperature. We find large-scale relationships between inter-annual variability in the
boundary conditions and inter-annual variability modelled on the shelf,
suggesting that dynamic downscaling may be possible (approach C). We also
show that for some variables there are opposing mechanisms correlated with the
NAO, for which dynamic downscaling may improve on the skill possible with
empirical forecasts. We conclude that there is potential for the development
of reliable seasonal forecasts for the NWS and consider the research
priorities for their development.
Could the mesoscale eddies be reproduced and predicted in the northern south China sea: case studies
Authors: Xu Dazhi , Zhuang Wei , Yan Youfang
Published: August 2018

Abstract. Great progress has been made in understanding the mesoscale eddies and their role on the large-scale structure and circulation of the oceans. However, many questions still remain to be resolved, especially with regard to the reproductivity and predictability of mesoscale eddies. In this study, the reproductivity and predictability of mesoscale eddies in the Northern SCS (NSCS), a region with strong eddy activity, are investigated with a focus on two typical anticyclonic eddies (AE1 and AE2) based on a HYCOM-EnOI Assimilated System. The comparisons of assimilated results and observations suggest that generation, evolution and propagation paths of AE1 and AE2 can be well reproduced and forecasted when their amplitude > 8 cm, although their forcing mechanisms are quite different. However, when their intensities are less than 8 cm, the generation and decay of these two mesoscale eddies cannot be well reproduced and predicted by the system. This result suggests, in addition to dynamical mechanisms, the spatial resolution of assimilation observation data and numerical models must be taken into account in reproducing and predicting mesoscale eddies in the NSCS.