bluuebunny/crossref_metadata_2025 huggingface dataset:
Fine particulate matter (PM2.5) trends in China, 2013–2018: contributions from meteorology
Authors: Zhai Shixian , Jacob Daniel J. , Wang Xuan , Shen Lu , Li Ke , Zhang Yuzhong , Gui Ke , Zhao Tianliang , Liao Hong
Published: May 2019

Abstract. Fine particulate matter (PM2.5) is a severe air pollution problem in China. Observations of PM2.5 have been available since 2013 from a large network operated by the China National Environmental Monitoring Center (CNEMC). The data show a general 30–50 % decrease of annual mean PM2.5 across China over the 2013–2018 period, averaging 5.2 μg m−3 a−1. Trends in the five megacity cluster regions targeted by the government for air quality control are 9.3 ± 1.8 μg m−3 a−1 (±95 % confidence interval) for Beijing-Tianjin-Hebei, 6.1 ± 1.1 μg m−3 a−1 for Yangtze River Delta, 2.7 ± 0.8 μg m−3 a−1 for Pearl River Delta, 6.7 ± 1.3 μg m−3 a−1 for Sichuan Basin, and 6.5 ± 2.5 μg m−3 a−1 for Fenwei Plain (Xi'an). Concurrent 2013–2018 observations of sulfur dioxide (SO2) and CO show that the declines in PM2.5 are qualitatively consistent with drastic controls of emissions from coal combustion. However, there is also a large meteorologically driven interannual variability of PM2.5 that complicates trend attribution. We used a stepwise multiple linear regression (MLR) model to quantify this meteorological contribution to the PM2.5 trends across China. The MLR model correlates the 10-day PM2.5 anomalies to wind speed, precipitation, relative humidity, temperature, and 850 hPa meridional wind velocity (V850). We find that meteorology made a minor but significant contribution to the observed 2013–2018 PM2.5 trends across China and that removing this influence reduces the uncertainty on the emission-driven trends. The mean PM2.5 decrease across China is 4.6 μg m−3 a−1 in the meteorology-corrected data, 12 % weaker than in the original data. The residual trends in the five megacity clusters attributable to changes in anthropogenic emission are 8.0 ± 1.1 μg m−3 a−1 for Beijing-Tianjin-Hebei (14 % weaker than the observed trend), 6.3 ± 0.9 μg m−3 a−1 for Yangtze River Delta (3 % stronger), 2.2 ± 0.5 μg m−3 a−1 for Pearl River Delta (19 % weaker), 4.9 ± 0.9 μg m−3 a−1 for Sichuan Basin (27 % weaker), and 4.9 ± 1.9 μg m−3 a−1 for Fenwei Plain (Xi'an; 25 % weaker). 2015–2017 observations of flattening PM2.5 in the Pearl River Delta, and increase in the Fenwei Plain, can be attributed to meteorology rather than to relaxation of emission controls.
Planetary boundary layer evolution over the Amazon rain forest in episodes of deep moist convection at ATTO
Authors: Oliveira Maurício I. , Acevedo Otávio C. , Sörgel Matthias , Nascimento Ernani L. , Manzi Antonio O. , Oliveira Pablo E. S. , Brondani Daiane V. , Tsokankunku Anywhere , Andreae Meinrat O.
Published: May 2019

Abstract. In this study, high-frequency, multi-level measurements performed from late October to mid-November of 2015 at a 80-m tall tower of the Amazon Tall Tower Observatory (ATTO) project in central Amazonas State, Brazil, were used to diagnose the evolution of thermodynamic and kinematic variables as well as scalar fluxes during the passage of outflows generated by deep moist convection (DMC). Outflow associated with DMC activity over or near the tall tower was identified through the analysis of storm echoes in base reflectivity data from S-band weather radar at Manaus, combined with the detection of gust fronts and cold pools utilizing tower data. Four outflow events were selected, three of which took place during the early evening transition or nighttime hours and one during the early afternoon. Results show that the magnitude of the drop in virtual potential temperature and changes in wind velocity during outflow passages vary according to the type, organization, and life cycle of the convective storm. Overall, the nocturnal events highlighted the passage of well-defined gust fronts with moderate decrease in virtual potential temperature and increase in wind speed. The early afternoon event lacked a sharp gust front and only a gradual drop in virtual potential temperature was observed, probably because of weak or undeveloped outflow. Sensible heat flux (H) experienced an increase at the time of gust front arrival, which was possibly due to sinking of colder air. This was followed by a prolonged period of negative H, associated with enhanced nocturnal negative H in the storms' wake. In turn, increased latent heat flux (LE) was observed following the gust front, owing to drier air coming from the outflow; however, malfunctioning of the moisture sensors during rain precluded a better assessment of this variable. Substantial enhancements of Turbulent Kinetic Energy (TKE) were observed during and after gust front passage, with values comparable to those measured in grass fire experiments, evidencing the highly turbulent character of convective outflows. The early afternoon event displayed slight decreases in the aforementioned quantities in the passage of the outflow. Finally, a conceptual model of the time evolution of H in nocturnal convective outflows observed at the tower site is presented.
Global inorganic nitrate production mechanisms: Comparison of a global model with nitrate isotope observations
Authors: Alexander Becky , Sherwen Tomás , Holmes Christopher D. , Fisher Jenny A. , Chen Qianjie , Evans Mat J. , Kasibhatla Prasad
Published: May 2019

Abstract. The formation of inorganic nitrate is the main sink for nitrogen oxides (NOx = NO + NO2). Due to the importance of NOx for the formation of tropospheric oxidants such as the hydroxyl radical (OH) and ozone, understanding the mechanisms and rates of nitrate formation is paramount for our ability to predict the atmospheric lifetimes of most reduced trace gases in the atmosphere. The oxygen isotopic composition of nitrate (Δ17O(nitrate)) is determined by the relative importance of NOx sinks, and thus can provide an observational constraint for NOx chemistry. Until recently, the ability to utilize Δ17O(nitrate) observations for this purpose was hindered by our lack of knowledge about the oxygen isotopic composition of ozone (Δ17O(O3)). Recent and spatially widespread observations of Δ17O(O3) have greatly reduced this uncertainty, and allow for an updated comparison of modeled and observed Δ17O(nitrate) and a reassessment of modeled nitrate formation pathways. Model updates based on recent laboratory studies of heterogeneous reactions renders dinitrogen pentoxide (N2O5) hydrolysis as important as NO2 + OH (both 41 %) for global inorganic nitrate production near the surface. All other nitrate production mechanisms represent less than 6 % of global nitrate production near the surface, but can be dominant locally. Updated reaction rates for aerosol uptake of NO2 result in significant reduction of nitrate and nitrous acid (HONO) formed through this pathway in the model, and render NO2 hydrolysis a negligible pathway for nitrate formation globally. Although photolysis of aerosol nitrate may have implications for NOx, HONO and oxidant abundances, it does not significantly impact the relative importance of nitrate formation pathways. Modeled Δ17O(nitrate) (28.6 ± 4.5 ‰) compares well with the average of a global compilation of observations (27.6 ± 5.0 ‰), giving confidence in the model's representation of the relative importance of ozone versus HOx (= OH + HO2 + RO2) in NOx cycling and nitrate formation.
A neural network radiative transfer model approach applied to
TROPOMI’s aerosol height algorithm
Authors: Nanda Swadhin , de Graaf Martin , Veefkind J. Pepijn , ter Linden Mark , Sneep Maarten , de Haan Johan , Levelt Pieternel F.
Published: May 2019

Abstract. To retrieve aerosol properties from satellite measurements of the oxygen A-band in the near infrared, a line-by-line radiative transfer model implementation requires a large number of calculations. These calculations severely restrict a retrieval algorithm's operational capability as it can take several minutes to retrieve aerosol layer height for a single ground pixel. This paper proposes a forward modeling approach using artificial neural networks to speed up the retrieval algorithm. The forward model outputs are trained into a set of neural network models to completely replace line-by-line calculations in the operational processor. Results of comparing the forward model to the neural network alternative show encouraging results with good agreements between the two when applied to retrieval scenarios using both synthetic and real measured spectra from TROPOMI (TROPOspheric Monitoring Instrument) on board the ESA Sentinel-5 Precursor mission. With an enhancement of the computational speed by three orders of magnitude, TROPOMI's operational aerosol layer height processor is now able to retrieve aerosol layer heights well within operational capacity.
Multi-scheme chemical ionization inlet (MION) for fast switching of reagent ion chemistry in atmospheric pressure chemical ionization mass spectrometry (CIMS) applications
Authors: Rissanen Matti P. , Mikkilä Jyri , Iyer Siddharth , Hakala Jani
Published: May 2019

Abstract. A novel chemical ionization inlet (Multi-scheme chemical IONization inlet, MION, Karsa Ltd, Helsinki, Finland) capable of fast switching between multiple reagent ion schemes is presented and its performance is demonstrated by measuring several known oxidation products from much studied cyclohexene and α-pinene ozonolysis systems, by applying consecutive bromide (Br−) and nitrate (NO3−) chemical ionization. Experiments were performed in flow tube reactors under atmospheric pressure and room temperature (22 °C) utilizing atmospheric pressure interface time-of-flight mass spectrometer (APi-ToF-MS, Tofwerk Ltd, Thun, Switzerland) as the detector. The application of complementary ion modes in probing the same steady-state reaction mixture enabled a far more complete picture of the detailed autoxidation process; the HO2 radical and the least oxidized reaction products were retrieved with Br− ionization, whereas the highest oxidized reaction products were detected in the NO3− mode, directly informing on the first steps and on the ultimate end-point of oxidation, respectively. While chemical ionization inlets with multiple reagent ion capabilities have been reported previously, an application in which the charging of the sample occurs at atmospheric pressure with practically no sample pretreatment, and with the potential to switch the reagent ion scheme within a second time-scale, has not been introduced previously. Also, the ability of bromide ionization to detect highly-oxygenated organic molecules (HOM) from atmospheric autoxidation reactions has not been demonstrated prior to this investigation.
An experimental 2DVAR retrieval using AMSR2
Authors: Duncan David Ian , Eriksson Patrick , Pfreundschuh Simon
Published: May 2019

Abstract. A two-dimensional variational retrieval (2DVAR) is presented for a passive microwave imager. The overlapping antenna patterns of all frequencies from the Advanced Microwave Scanning Radiometer-2 (AMSR2) are explicitly simulated to attempt retrieval of near surface wind speed and surface skin temperature at finer spatial scales than individual antenna beams. This is achieved, with the effective spatial resolution of retrieved parameters shown by analysis of 2DVAR averaging kernels. Sea surface temperature retrievals achieve about 30 km resolution, with wind speed retrievals at about 10 km resolution. It is argued that multi-dimensional optimal estimation permits greater use of total information content from microwave sensors than other methods, with no compromises on target resolution needed; instead, various targets are retrieved at the highest possible spatial resolution, driven by the channels' sensitivities. All AMSR2 channels can be simulated within near their published noise characteristics for observed clear-sky scenes, though calibration and emissivity model errors are key challenges. This experimental retrieval shows the feasibility of 2DVAR for cloud-free retrievals, and opens the possibility of standalone 3DVAR retrievals of water vapour and hydrometeor fields from microwave imagers in the future. The results have implications for future satellite missions and sensor design, as spatial oversampling can somewhat mitigate the need for larger antennas in the push for higher spatial resolution.
On modelling the kinematics and evolutionary properties of pressure pulse driven impulsive solar jets
Authors: Singh Balveer , Sharma Kushagra , Srivastava Abhishek K.
Published: May 2019

Abstract. In this paper, we describe the kinematical and evolutionary properties of the impulsive solar jets using numerical simulation by Godunov-type PLUTO code. These type of chromospheric jets are originated by the pressure pulse, which mimics the after effects of the localized heating in the lower solar atmosphere. These jets may responsible for the transporting of mass and energy in the localized upper atmosphere (i.e., corona). The automated detection of height-time profiles for the jets originated by imposing the different pressure pulses exhibit the asymmetric near parabolic profiles. This infers that the upward motion of the jet occurs under the influence of pressure perturbation. However, its downward motion is not only governed by the gravitational free fall but also due to the complex plasma motions near its base due to the counter propagating pulses. Maximum height and life-time of the jets w.r.t. strength of the pressure pulse show a linear increasing trend. This suggests that if the extent of the heating and thus pressure perturbations will be higher then more longer chromospheric jets can be triggered from the same location in the chromosphere. Although, we present the kinematics and evolutionary properties of the a isolated jets, but usually such jet triggering sites with pressure perturbations exhibits the formation of the multiple jets along with the significant brightening at their base. In conclusions, our model mimics the properties and evolution of the impulsive jets (e.g., macrospicules, network jets, isolated repeated cool jets, confined and small surges etc).
Cushion bogs are stronger carbon dioxide net sinks than
moss-dominated bogs as revealed by eddy covariance measurements
on Tierra del Fuego, Argentina
Authors: Holl David , Pancotto Verónica , Heger Adrian , Camargo Sergio Jose , Kutzbach Lars
Published: May 2019

Abstract. The near-pristine bog ecosystems of Tierra del Fuego in southernmost Patagonia have so far not been studied in terms of their current carbon dioxide (CO2) sink strength. CO2 flux data from southern hemisphere peatlands is scarce in general. In this study, we present CO2 net ecosystem exchange (NEE) fluxes from two Fuegian bog ecosystems with contrasting vegetation communities. One site is located in a glaciogenic valley and developed as a peat moss-dominated raised bog, the other site is a vascular plant-dominated cushion bog located at the coast of the Beagle Channel. We measured NEE fluxes with two identical eddy covariance (EC) setups at both sites for more than two years. With the EC method, we were able to observe NEE fluxes on ecosystem level and at high temporal resolution. Using a mechanistic modeling approach, we estimated daily NEE models to gap-fill and partition the half-hourly net CO2 fluxes into components related to photosynthetic uptake (gross primary production, GPP) and to total ecosystem respiration (TER). We found a larger relative variability of annual NEE sums between both years at the moss-dominated site. A warm and dry first year led to comparably high TER sums. Photosynthesis was also promoted by warmer conditions but less strong than TER with respect to absolute and relative GPP changes. The annual NEE-C uptake was more than three times smaller in the warm year. Close to the sea at the cushion bog site, the mean temperature difference between both observed years was less pronounced, and TER stayed on similar levels. A higher amount of available radiation in the second observed year led to an increase of GPP (5 %) and NEE (35 %) carbon (C) uptake. The average annual NEE-C uptake of the cushion bog (−122 ± 76 g m−2 a−1, n = 2) was more than four times larger than the average uptake of the moss-dominated bog (−27 ± 28 g m−2 a−1, n = 2).
6200 years of human activities and environmental change in the northern central Alps
Authors: von Scheffer Clemens , Lange Annika , De Vleeschouwer François , Schrautzer Joachim , Unkel Ingmar
Published: May 2019

Abstract. In this study, we combine erosion and anthropogenic proxies (Ti, Pb) from calibrated portable XRF with pollen and radiocarbon chronologies in peat from mires of the Kleinwalser Valley (Kleinwalsertal, Vorarlberg, Austria) to reconstruct palaeoenvironmental change and human impact in the northern central Alps. Favoured by a wetter climate, two analysed mires formed 6200 years ago in a densely forested valley. Landscape opening suggests that the first anthropogenic impact emerged around 5700 to 5300 cal BP. Contemporaneously, lead enrichment factors (Pb EFs) indicate metallurgical activities, predating the earliest archaeological evidence in the region. Pollen and erosion proxies show that large-scale deforestation and land use by agro-pastoralists took place from the mid- to late Bronze Age (3500 to 2800 cal BP). This period was directly followed by a prominent peak in Pb EF, pointing to metallurgical activities again. After 200 cal CE, a rising human impact was interrupted by climatic deteriorations in the first half of the 6th century CE, probably linked to the Late Antique Little Ice Age. The use of the characteristic Pb EF pattern of modern pollution as a time marker allows us to draw conclusions about the last centuries. These saw the influence of the Walser people, arriving in the valley after 1300 cal CE. Later, the beginning of tourism is reflected in increased erosion signals after 1950 cal CE. Our study demonstrates that prehistoric humans were intensively shaping the Kleinwalser Valley's landscape, well before the arrival of the Walser people. It also demonstrates the importance of palaeoenvironmental multiproxy studies to fill knowledge gaps where archaeological evidence is lacking.
A Universal and Multi-dimensional Model for Analytical Data on
Geological Samples
Authors: He Yutong , Tian Di , Wang Hongxia , Yao Li , Chen Pengfei
Published: May 2019

Abstract. To promote the sharing and reutilization of geoanalytical data, various geoanalytical databases have been established over the last 30 years. Data models, which form the core of a database, are themselves the subjects of intensive studies. Data models determine the contents stored in the databases and applications of the databases. However, most geoanalytical data models have been designed for specific geological applications, which has led to strong heterogeneity between databases. It is therefore difficult for researchers to communicate and integrate geoanalytical data between databases. In particular, every time a new database is constructed, the time-consuming process of redesigning a data model significantly increases the development cycle. This study introduces a new data model that is universally applicable and highly efficient. The data model is applied to various geoanalytical methods and corresponding applications, and comprehensive analytical data contents together with associated background metadata are summarized and catalogued. Universal data attributes are then designed based on these metadata, which means that the model can be used for any geoanalytical database. Additionally, a multi-dimensional data mode is adopted, providing geological researchers with the ability to analyze geoanalytical data from six or more dimensions with high efficiency. Part of the model is implemented with the typical database system-MySQL and comprehensive comparison experiments with existing geoanalytical data model are presented. The result unambiguously proves that the data model developed in this paper exceeds existing models in efficiency.
Evaluations of an ocean bottom electro-magnetometer and preliminary results offshore NE Taiwan
Authors: Lin Ching-Ren , Chiang Chih-Wen , Huang Kuei-Yi , Hsiao Yu-Hung , Chen Po-Chi , Chang Hsu-Kuang , Jang Jia-Pu , Chang Kun-Hui , Lin Feng-Sheng , Lin Saulwood , Kuo Ban-Yuan
Published: May 2019

Abstract. The first stage of field experiments involving the design and construction of a low-power consumption ocean bottom electro-magnetometer (OBEM) has been completed. To improve the performance of the OBEM, we rigorously evaluated each of its units, e.g., the data loggers, acoustic parts, internal wirings, and magnetic and electric sensors, to eliminate unwanted events such as unrecovered or incomplete data. The evaluations of the procedure included the following. Data logger: digitizer sensitivity, linearity, and errors Acoustic transceiver: “ENABLE,” “DISABLE,” “RANGE,” “RELEASE1,” “RELEASE2,” and “OPTION1” functions Magnetic sensor: sensitivity of the fluxgate and orthogonality Electrical receiver: potential voltage, impedance, and frequency responses Power consumption: the maximum operating current of two sets of batteries Deployment and recovery procedures on deck We confirmed the optimal performance of the OBEM after repeatedly testing the procedures. The first offshore deployment of the OBEM together with ocean bottom seismographs (OBSs) was performed in NE Taiwan, where the water depth is approximately 1,400 m. The total intensity of the magnetic field (TMF) measured by the OBEM varied in the range of 44,100–44,150 nT, which corresponded to the proton magnetometer measurements. The daily variations of the magnetic field were recorded using the two horizontal components of the OBEM magnetic sensor. We found that the inclinations and magnetic data of the OBEM varied with two observed earthquakes when compared to the OBS data. The potential fields of the OBEM were slightly, but not obviously, affected by the earthquakes.
Method for testing the calibration of acceleration and pressure gauges installed at the ocean bottom
Authors: Nosov Mikhail , Karpov Viacheslav , Kolesov Sergey , Sementsov Kirill , Matsumoto Hiroyuki , Kaneda Yoshiyuki
Published: May 2019

Abstract. A method is proposed for testing pressure gauges and z-accelerometers, installed in ocean-bottom observatories. The method is based on the linear relationship between variations of the ocean-bottom pressure and the z-acceleration, observed during seismic movements of the bottom within the frequency band of "forced oscillations". Calculation of the boundaries of this frequency band is based on the ocean depth at the observatory site making use of explicit formulae. In the case of correct calibration of the gauges calculation of the ratios of power spectra of bottom pressure variations and the z-accleration within the band of "forced oscillations" yields constant values equal to the square ratio of the total mean pressure and the gravity acceleration. The conditions for application of the proposed method are formulated.
A network of magnetometers for multi-scale urban science and informatics
Authors: Bowen Trevor A. , Zhivun Elena , Wickenbrock Arne , Dumont Vincent , Bale Stuart D. , Pankow Christopher , Dobler Gregory , Wurtele Jonathan S. , Budker Dmitry
Published: May 2019

Abstract. The magnetic signature of an urban environment is investigated using a
geographically distributed network of fluxgate magnetometers deployed in and
around Berkeley, California. The system hardware and software are described
and initial operations of the network are reported. The sensors measure
vector magnetic fields at a 3960 Hz sample rate and are sensitive to
0.1 nT/Hz. Data from individual stations are
synchronized to ±120 µs using global positioning system (GPS) and computer system clocks
and automatically uploaded to a central server. We present the initial
observations of the network and preliminary efforts to correlate
sensors. A wavelet analysis is used to study observations of the urban
magnetic field over a wide range of temporal scales. The Bay Area Rapid
Transit (BART) is identified as the dominant signal in our observations,
exhibiting aspects of both broadband noise and coherent periodic features.
Significant differences are observed in both day–night and weekend–weekday
signatures. A superposed epoch analysis is used to study and extract the BART
signal.
A stochastic rupture earthquake code based on the fiber bundle model (TREMOL v0.1): application to Mexican subduction earthquakes
Authors: Monterrubio-Velasco Marisol , Rodríguez-Pérez Quetzalcóatl , Zúñiga Ramón , Scholz Doreen , Aguilar-Meléndez Armando , de la Puente Josep
Published: May 2019

Abstract. In general terms, earthquakes are the result of brittle
failure within the heterogeneous crust of the Earth. However, the rupture
process of a heterogeneous material is a complex physical problem that is
difficult to model deterministically due to numerous parameters and
physical conditions, which are largely unknown. Considering the variability
within the parameterization, it is necessary to analyze earthquakes by means
of different approaches. Computational physics may offer alternative ways to
study brittle rock failure by generating synthetic seismic data based on
physical and statistical models and through the use of only few free parameters.
The fiber bundle model (FBM) is a stochastic discrete model of material
failure, which is able to describe complex rupture processes in heterogeneous
materials. In this article, we present a computer code called
the stochasTic Rupture Earthquake MOdeL, TREMOL. This code is based on
the principle of the FBM to investigate the rupture process of asperities on
the earthquake rupture surface. In order to validate TREMOL, we carried out a
parametric study to identify the best parameter configuration while
minimizing computational efforts. As test cases, we applied the final
configuration to 10 Mexican subduction zone earthquakes in order to compare
the synthetic results by TREMOL with seismological observations. According to
our results, TREMOL is able to model the rupture of an asperity that is
essentially defined by two basic dimensions: (1) the size of the fault plane
and (2) the size of the maximum asperity within the fault plane. Based on
these data and few additional parameters, TREMOL is able to generate numerous
earthquakes as well as a maximum magnitude for different scenarios within a
reasonable error range. The simulated earthquake magnitudes are of the same
order as the real earthquakes. Thus, TREMOL can be used to analyze the
behavior of a single asperity or a group of asperities since TREMOL considers
the maximum magnitude occurring on a fault plane as a function of the size of
the asperity. TREMOL is a simple and flexible model that allows its users
to investigate the role of the initial stress configuration and the
dimensions and material properties of seismic asperities. Although various
assumptions and simplifications are included in the model, we show that
TREMOL can be a powerful tool to deliver promising new insights into
earthquake rupture processes.
Historical modelling of changes in Lake Erken thermal conditions
Authors: Moras Simone , Ayala Ana I. , Pierson Don C.
Published: May 2019

Abstract. The thermal structure of lakes is strictly related to climate and to the variability of thermal and mixing dynamics. In this study, a physical hydrodynamic model (GOTM) was used to reconstruct daily time-step water temperature of Lake Erken (Sweden) over the period 1961–2017, using seven climatic parameters as forcing data: wind speed (WS), air temperature (Air T), atmospheric pressure (Air P), relative humidity (RH), cloud cover (CC), precipitation (DP) and shortwave radiation (SWR). The model was calibrated against real water temperature data collected during the study interval, and the calibrated model revealed a good match between modelled and observed temperature (RMSE = 1.112 °C). From the long-term simulations of water temperature, this study focused on detecting possible trends in water temperature over the entire study interval 1961–2017 and in the sub-intervals 1961–1987 and 1988–2017. The analysis of the simulated temperature showed that epilimnetic temperature has increased on average by +0.43 °C/decade and +0.809 °C/decade in spring and autumn in the sub-interval 1988–2017. Summer epilimnetic temperature has increased by +0.348 °C/decade over the entire interval 1961–2017. Hypolimnetic temperature has increased significantly in the sub-interval 1988–2016 by +0.827 °C/decade in autumn. Whole-lake temperature showed a significant increasing trend in the sub-interval 1988–2017 during spring (+0.378 °C/decade) and in autumn (+0.809 °C/decade). Moreover, this study showed that changes in the phenology of thermal stratification, have occurred over the 57-years period of study. Since 1961 the stability of stratification (Schmidt Stability) has increased by 5.535 J m−2/decade. The duration of thermal stratification has increased by 7.083 days/decade, correspondent with an earlier onset of stratification of ~ 16 days and to a delay of stratification termination of ~ 26 days. The average thermocline depth during stratification became shallower by ~ 1.242 m, and surface-bottom temperature difference increased over time by +0.249 °C/decade. The creation of daily-time step water temperature dataset not only provided evidence of changes in Erken thermal structure over the last decades, but it is also a valuable resource of information that can help in future research on the ecology of Lake Erken. The use of readily available meteorological data to reconstruct Lake Erken's past water temperature is shown to be a useful method to evaluate long-term changes in lake thermal structure, and it is a method that can be extended to other lakes.
Estimation of geostrophic current in the Red Sea based on sea level anomalies derived from extended satellite altimetry data
Authors: Taqi Ahmed Mohammed , Al-Subhi Abdullah Mohammed , Alsaafani Mohammed Ali , Abdulla Cheriyeri Poyil
Published: May 2019

Abstract. Geostrophic current data near the coast of the Red Sea have large gaps.
Hence, the sea level anomaly (SLA) data from Jason-2 have been reprocessed and
extended towards the coast of the Red Sea and merged with AVISO data at the
offshore region. This processing has been applied to build a gridded dataset
to achieve the best results for the SLA and geostrophic current. The results
obtained from the new extended data at the coast are more consistent with the
observed data (conductivity–temperature–depth, CTD) and hence geostrophic current calculation. The patterns
of SLA distribution and geostrophic currents are divided into two seasons:
winter (October–May) and summer (June–September). The geostrophic currents
in summer are flowing southward over the Red Sea except for narrow
northward flow along the east coast. In winter, currents flow to the north
for the entire Red Sea except for a small southward flow near the central
eastern and western coast. This flow is modified by the presence of cyclonic
and anticyclonic eddies, which are more concentrated in the central and
northern Red Sea. The results show anticyclonic eddies (AEs) on the eastern
side of the Red Sea and cyclonic eddies (CEs) on the western side during
winter. In summer, cyclonic eddies are more dominant for the entire Red Sea.
The result shows a change in some eddies from anticyclonic during winter to
cyclonic during summer in the north between 26.3 and 27.5∘ N.
Furthermore, the life span of cyclonic eddies is longer than that of
anticyclonic eddies.
Dimas de Miguel y la jerga luliana de la universalidad
Authors: Blanco Mourelle Noel
Published: May 2019

En este trabajo examino la figura de Dimas de Miguel y, en particular, de su opúsculo Breve y compendioso compendio de la arte de Raymundo Llull como parte de un debate en torno a la noción de universalidad. Dimas de Miguel perteneció al círculo intelectual que rodeó a Juan de Herrera y que se asoció al rey Felipe II en las últimas décadas de su vida. Este círculo conservó los aspectos misioneros originales del lulismo, pero se concentró en la faceta del arte luliano que prometía una lógica alrededor de la cual todas las disciplinas académicas podían organizarse. Me centraré en tres puntos de análisis de esta universalidad: los catálogos como mapas del legado de la obra luliana en distintas bibliotecas; el establecimiento de un vocabulario de la universalidad en el mencionado tratado de Dimas; y, por último, en la argumentación de esta universalidad en oposición a sus detractores académicos y eclesiásticos.
Cautivos del corso español. El trato a los prisioneros durante el siglo XVIII
Authors: Moya Sordo Vera
Published: May 2019

Cautivos del corso español. El trato a los prisioneros durante el siglo XVIII
Emerging Technologies and the Accounting Profession: Trends and Topics for Practitioners to Consider
Authors: Stein Smith Sean
Published: May 2019

Emerging technology and technology tools such as blockchain, artificial intelligence, robotic process automation, and automation at large continue to drive change and disruption throughout the broader financial services landscape. While numerous articles, webcasts, and books have been put together analyzing these different topics and the implications they might have on different areas of the professional landscape, this article proposes a different approach. Instead of focusing on definitions, terminology, or assessing potential impacts at a higher level or through a broad scope of possible applications, this research examines certain specific trends and aspects of these technologies and the impacts they will generate on the profession. Definitions and work terminology will, of course, be a part of this research, but that does not form the core of this piece. Rather, and written with both a practitioner and academic audience in mind, certain emerging topics such and applications built on top of blockchain technology, as well as implementation issues connected to other emerging issues, are the core of this piece.
The Impact of HR Analytics on the Training and Development Strategy - Private Sector Case Study in Lebanon
Authors: Barbar Kamel , Choughri Radwan , Soubjaki Moetaz
Published: May 2019

This study investigated the impact of HR analytics on the training and development strategy of private organizations in Lebanon. It sought to test four hypotheses namely: There is a significant relationship between HR analytics use in large businesses and the development of employee skills; there is a significant relationship between HR analytics use in older businesses and the development of employee skills; there is a significant relationship between HR analytics use in large businesses and the retention of employees; and there is a significant relationship between HR analytics use in older businesses and the retention of employee. HR analytics has a significant influence on the development of employee skills and HR analytics has a significant influence on the development of HR training strategy. The study relied on a quantitative correlational research method with the help of an online questionnaire as the data collection instrument. A total of 302 respondents from the private sector in Lebanon returned valid responses to the questionnaire. The results validated each of the four hypotheses. They revealed that HR professionals rely on HR analytics to formulate employee development strategies. Data from HR analytics is used to predict potential outcomes of important HR and organization strategy decisions. In conclusion, the findings from this study imply that businesses should integrate HR professionals and HR analytics into the process of decision making and development strategy formulation.
The security of critical infrastructure in the concept of the Territorial Defence Force of the Republic of Poland
Authors: Maciejczyk-Cień Piotr
Published: May 2019

Nowadays, humanity has become dependent on the devices and systems which form part of everyday life. This relation was made clear by the terrorist attacks in New York, Madrid and London. The attacks resulted not only in human casualties and damage to infrastructure, but also made people aware of the close relations between the damage and the effective operation of the rescuers. This gave rise to the need to face the problem of protecting the infrastructure which is important for the security of the state and its citizens. At the same time, the issue of threats to critical infrastructure has started to emerge more and more in the literature devoted to internal security and stopped being associated solely with military concepts. In Poland, the notion of ‘critical infrastructure’ first started to appear in government documents and literature in 2007 after the introduction of the Crisis Management Act. The legislator specifies in the document the conceptual range of critical infrastructure which is closely related to the functioning of facilities, devices, and installations relevant for the security of the state and citizens. The following systems were regarded as critical infrastructures: the energy and fuel, communications and ICT, transport, rescue, financial, food and water supply, and healthcare systems, and also the one related to chemical and radioactive substances. This paper is an attempt at characterising the defence of critical infrastructure in Poland and the possibilities of preventing threats to important state security systems in the context of the establishment of the Territorial Defence Force.
Security culture and security anthropology
Authors: Trzciński Łukasz , Piwowarski Juliusz
Published: May 2019

The topic of the article is the relationship between security culture and anthropology of securi-ty. The authors recall the most important definitions of security culture and anthropology of security, both of which belong to the discipline of security sciences, and conclude that culture, including its special sphere called security culture, is a human creation that strongly affects people, so it would be difficult to explore it scientifically without anthropological knowledge and tools. The authors give an account of the development of security sciences research in Poland, and point out that its subdiscipline called security anthropology is not fully formed yet, its theoretical and methodological identity still being underway; however, it develops dynamically. In forming this new subdiscipline of security sciences, apart from applying mul-tidisciplinary research, it is also necessary to consider different types of anthropology, above all biological, cultural and philosophical anthropology. The authors signalize the potential di-rections of research within the field and conclude that a methodological framework of securi-ty anthropology should be worked out, in a form that is most important and legible at the cur-rent stage of the development of science.
Regulierung von Internetkommunikationsdiensten
Authors: Bulowski Stefan
Published: May 2019

Internet-based communications services enable interpersonal communication via the Internet. Among them are Internet telephony services (voice over IP, e.g. Skype), instant messaging services (e.g. WhatsApp) and e-mails. Many of these services have been popular since the 1990s, but it is still not clear how they are legally classified and which rules they have to adhere to.
This thesis examines whether they fall within the scope of telecommunications law and how they should be regulated. It analyses sector-specific antitrust law, consumer protection law, public safety law and privacy law. Another aspect are problems caused by rapid technological change. Therefore, the work concludes by comparing the German and European legal situation with the legal framework in the United States in terms of each law’s ability to respond.
Dlg1 activates beta-catenin signaling to regulate retinal angiogenesis and the blood-retina and blood-brain barriers
Authors: Cho Chris , Wang Yanshu , Smallwood Philip M , Williams John , Nathans Jeremy
Published: May 2019

Beta-catenin (i.e., canonical Wnt) signaling controls CNS angiogenesis and the blood-brain and blood-retina barriers. To explore the role of the Discs large/membrane-associated guanylate kinase (Dlg/MAGUK) family of scaffolding proteins in beta-catenin signaling, we studied vascular endothelial cell (EC)-specific knockout of Dlg1/SAP97. EC-specific loss of Dlg1 produces a retinal vascular phenotype that closely matches the phenotype associated with reduced beta-catenin signaling, synergizes with genetically-directed reductions in beta-catenin signaling components, and can be rescued by stabilizing beta-catenin in ECs. In reporter cells with CRISPR/Cas9-mediated inactivation of Dlg1, transfection of Dlg1 enhances beta-catenin signaling ~4 fold. Surprisingly, Frizzled4, which contains a C-terminal PDZ-binding motif that can bind to Dlg1 PDZ domains, appears to function independently of Dlg1 in vivo. These data expand the repertoire of Dlg/MAGUK family functions to include a role in beta-catenin signaling, and they suggest that proteins other than Frizzled receptors interact with Dlg1 to enhance beta-catenin signaling.
Electrical properties of relaxed p-GaN/p-AlGaN superlattices and their application in ultraviolet-B light-emitting devices
Authors: Sato Kosuke , Yasue Shinji , Ogino Yuya , Iwaya Motoaki , Takeuchi Tetsuya , Kamiyama Satoshi , Akasaki Isamu
Published: May 2019

The relaxation ratio of p-GaN/p-AlGaN superlattices was controlled by using different AlGaN underlying layers and the effects of relaxation on the electrical properties were investigated. High hole concentrations over 1 × 1018 cm−3 at room temperature and low activation energies below 120 meV were obtained regardless of the relaxation ratio. Using a p-GaN/p-Al0.5Ga0.5N superlattice, current injection at 1 A corresponding to 33.3 kA cm−2 was achieved without a significant drop in output power in an ultraviolet-B light-emitting diode including undoped AlGaN waveguide layers.
Modulation of stress response and productive performance of Litopenaeus vannamei through diet
Authors: Martínez-Antonio Eliza M. , Racotta Ilie S. , Ruvalcaba-Márquez Juan C. , Magallón-Barajas Francisco
Published: May 2019

The high tolerance of Litopenaeus vannamei to a wide range of salinity (1–50 psu) makes this species an excellent candidate for culture under low salinity, decreasing shrimp epidemics and water pollution in some coastal areas. However, salinity levels outside the optimal range could impose several physiological constraints that would in turn affect growth and survival, particularly in the presence of additional stressors (e.g. high densities, handling practices, and hypoxia). Despite shrimp susceptibility to individual stressors has been widely addressed, information regarding response to chronic and acute stressors combined and its relation to diet is scarce. Thus, the aim of our study was to determine the effect of diet on the susceptibility to chronic (low salinity) and acute (hypoxia and escape response) stressors in terms of culture performance and physiological indicators. We evaluated overall performance during culture of L. vannamei at low salinity (6 psu), fed with an experimental diet with low protein and high carbohydrate content (26% protein and 6% fish meal plus probiotic mixture) and compared to a commercial formula with high protein and low carbohydrate content (40% crude protein and 20% fish meal without probiotic mixture). At the end of the rearing experiment, shrimp were exposed to two types of acute stress, hypoxia and escape. Biochemical (hemocyanin, total proteins, glucose, and lactate) and bioenergetic (adenylic energy charge and arginine phosphate levels) variables were measured to assess chronic stress response (salinity) and acute stress response (hypoxia or escape). The experimental diet resulted in higher muscle energy status that was not affected by low salinity, although lipid levels were lower under this condition. This diet partially counteracted the low performance at low salinity and promoted greater protein efficiency. Hypoxia induced strong hyperglycemic and lactate increase as response, whereas escape response was characterized by a depletion of arginine phosphate levels, with a stronger decrease in shrimp fed experimental diet, due to the high initial level of this reserve. Some data (glucose levels in hemolymph and lipids in hepatopancreas) suggest that shrimp under chronic stress conditions (low salinity and high densities) present a low ability to respond to subsequent acute stressors such as hypoxia or escape. This work indicates that diet can increase the energy status of shrimp, enabling them to overcome potential multifactorial stressors, which are common in farming systems.
oprD Genes Detected in Pseudomonas aeruginosa Isolates from a Teaching Hospital but Lost in a Carbapenem-Resistant Strain
Authors: Nmema Eucharia E. , Osuagwu Chioma S. , Anaele Eunice N.
Published: May 2019

Aims: The aims of the study were to evaluate the multidrug resistance profile and mechanisms of carbapenem resistance in Pseudomonas aeruginosa clinical isolates using phenotypic and genotypic methods.

Study Design: A descriptive laboratory based study.

Place and Duration of Study: Microbiology Laboratory, Ondo State University of Science and Technology, Okitipupa, and Biotechnology Laboratory, Ladoke Akintola University of Technology, Osogbo, Nigeria, between June 2017 and November 2018.

Methodology: Ten P. aeruginosa isolates were recovered from patients at Lagos University Teaching Hospital, and susceptibilities to imipenem (10 µg), meropenem (10 µg) and a panel of antibiotics were performed by the disk diffusion method. Genotypic methods including Polymerase Chain Reactions (PCR) and agarose gel electrophoresis were carried out according to established protocols. oprD and blaIMP gene primers were used for the PCR amplification.

Results: Fifty percent (50%) of the isolates showed multiple drug resistance. Four isolates (40%) were carbapenem resistant (CR). oprD gene was detectedin 90% (9/10) of the isolates. 75% (3/4) of CR strains were among the strains showing oprD gene. 25% (1/4) CR strain (PA1421) was oprD negative. Loss or mutation of oprD gene seems to be the mechanism of carbapenem resistance in strain PA1421.

Conclusion: Loss or mutation of oprD gene was identified in this study as a mechanism of carbapenem resistance. oprD gene encodes the outer membrane protein (OprD) porin in P. aeruginosa whose deficiency confers resistance to carbapenems, especially imipenem. Surveillance of the antimicrobial susceptibility patterns of P. aeruginosa is of critical importance in understanding new and emerging resistance trends, reviewing antibiotic policies and informing therapeutic options.