bluuebunny/crossref_metadata_2025 huggingface dataset:
Adsorption of Copper(II) on Dithizone-Immobilized Coal Fly Ash
Authors: Putri Violla Bestari Ayu Sabrina , Siswanta Dwi , Mudasir Mudasir
Published: April 2020

The adsorption of Cu (II) ions onto selective adsorbent of coal fly ash from Sugar Factory Madukismo, Yogyakarta, Indonesia modified with dithizone has been investigated in batch mode. Some parameters influencing immobilization of dithizone and adsorption of Cu (II) were optimized including an effect of pH, contact time and initial concentration of Cu (II) ions. The FT-IR and XRD analytical results show that the surface of coal fly ash can be modified by immobilization of selective organic ligand towards Cu (II) ions. The optimum conditions for adsorption of Cu (II) are achieved at pH 5, the optimum mass of DICFA and ACFA for copper adsorption were 0.2 g. Kinetics adsorption for copper ions follows pseudo-second-order kinetics with optimum adsorption contact time 60 min for DICFA and ACFA. Isotherms adsorption for Cu ion follow the Langmuir isotherms with chemisorption process and optimum concentration of Cu ion adsorption of 70 mg.L-1 for DICFA and ACFA.
Isothermal Vapor-Liquid Equilibrium Measurement of Isobutanol + Isooctane/N-Heptane Binary Mixtures at Temperatures Range of 303.15-323.15 K
Authors: Nurmawati Ardika , Tetrisyanda Rizky , Wibawa Gede
Published: April 2020

The addition of alcohol as an oxygenated compound in gasoline blends may increase the vapor pressure of gasoline mixture. As a result, the study of vapor-liquid equilibrium for gasoline component and alcohol is necessary. In this study, the vapor-liquid equilibrium of isobutanol – isooctane/n-heptane blends were obtained experimentally at temperatures in the range 303.15 to 323.15 K using modified simple quasi-static ebulliometer. The apparatus was validated by comparing the vapor pressure of pure isobutanol, isooctane, and n-heptane with the published data and giving average absolute deviation (AAD) between experimental and calculated ones with magnitude less than 1.0%. The addition of isobutanol with the mole fraction range from 0.2 to 0.6 would increase the vapor pressure of the isooctane and n-heptane up to 12% and 14% respectively. The vapor pressure of binary mixtures was correlated with the Wilson, Non-random two-liquid (NRTL), and Universal quasi-chemical (UNIQUAC) equations with AAD 1.6%, 1.5%, and 1.7%, respectively for isobutanol + isooctane system and 1.8%, 1.7%, and 2.0%, respectively for isobutanol + n-heptane system. The systems studied show positive deviation from Raoult’s Law.
Synthesis Strategy of Hierarchical Alumiosilicates from Low Grade Indonesian Kaolin with Adjusted Activity in Acetalization Reaction
Authors: Hartati Hartati , Tjahjandarie Tjitjik Srie , Purwaningsih Aning , Murti Susana , Ikhtiarsih Nastiti Mustika Rizki , Mardho Dea Zaqiatul , Saputri Nastiti Heru , Lamanele Christina Natalia , Firda Putri Bintang Dea
Published: April 2020

Synthesis strategy of hierarchical aluminosilicates was carried out by varying the starting material, type of a basic solution, and the hydrothermal condition. Aluminosilicate was synthesized using pre-treated low-quality kaolin by three kinds of basic solution, such as sodium hydroxide, sodium fluoride, and tetrapropyl ammonium hydroxide. The hydrothermal condition was carried out by gradual temperature and constant temperature. The desired mole ratio of Si/Al achieved by dealumination or by addition of silica. Products were characterized by X-ray diffraction, FTIR spectrometry, and nitrogen physisorption. Cation exchange was carried out on the product to obtain an acid catalyst. The acidity test of the catalyst was carried out by FTIR-pyridine spectrometry. The catalyst activity test was carried out to the acetalization reaction of 3,4-dimethoxybenzaldehyde with propylene glycol. The results showed that the catalyst synthesized with the basic solution of tetrapropyl ammonium hydroxide had the highest acid site number and the highest conversion of 3,4-dimethoxybenzaldehyde to acetal.
Immobilization of Salicylic Acid on Ni-Zn Layered Hydroxide Salts
Authors: Amnillah Muhammad Robith Tahta , Suyanta Suyanta , Santosa Sri Juari
Published: April 2020

Ni-Zn Layered hydroxide salt (Ni-Zn LHS) has been synthesized from equimolar Ni(NO3)2 and Zn(NO3)2 by co-precipitation method using NaOH. The formation of layered assembly is confirmed in X-ray diffractogram, i.e. by the appearance of peaks at 2θ: 9.60°, 19.40°, 33.48°, and 59.76° which corresponds to diffraction plane (001), (003), (020), and (040), respectively. The synthesized Ni-Zn LHSs possessed the point of zero charge (pHpzc) at pH 8 and nitrate as the interlamellar ion. The incorporation of salicylic acid into LHS can extend the property of LHS as a reductive adsorbent in the application of metal recovery. The immobilization of salicylic acid on the Ni-Zn-LHS was successfully done and indicated the strong pH-dependent property. The immobilization of salicylic acid on Ni-Zn LHSs was optimum at pH 7 and followed better the Langmuir than Freundlich isotherm models with immobilization capacity 64.93 mg/g. After the immobilization of salicylic acid, the basal spacing of Ni-Zn LHSs did not enlarge indicating that the immobilized salicylic acid was on the outer layer without entering the interlayer and this immobilized salicylic acid was stable at medium pH range 3 to 9.
Dysprosium (Dy) Separation from Yttrium Concentrate in Nitric Acid Solution Using Aliquat 336 Solvent
Authors: Basuki Kris Tri , Arifudin Ridwan , Pusparini Wahyu Rachmi , Saputra Andri
Published: April 2020

Similarity of chemical and physical properties between rare-earth elements (REEs) and Dy is the main concern in order to get Dy with high purity, which it is necessary to do separation by extraction process. The purpose of this research is to obtain the optimum condition of operation (stirring time and rate, concentration of nitric acid, feed, and solvent) and determine the distribution constant, separation factor, and extraction efficiency of Dy using Aliquat 336. This research was conducted by varying stirring time (10, 15, 20, 30, 40 minutes), stirring rate (100, 150, 200, 250, 300 rpm), nitric acid concentration (2, 3, 4, 5, 6 N), feed concentration (25,000; 50,000; 100,000; 150,000; 200,000 ppm) and solvent concentration (10, 20, 30, 40, 50 % v/v). The optimum result is achieved when operation is carried out at stirring 100 rpm about 15 minutes in nitric acid 3 N with 100,000 ppm of feed concentration using 30% solvent concentration (v/v) which extract more Dy element than Yttrium (Y) and Godolinium (Gd). The highest distribution constant of Dy is 0.427, separation factor of Dy-Y is 6.831, separation factor of Dy-Gd is 1.799, and extraction efficiency of Dy is 31.604%.
Effect of Simultaneous Saccharification and Fermentation (SSF) Time on Ethanol Production from Spent Medium of Oyster Mushroom (Pleurotus ostreatus)
Authors: Irawati Denny , Pradipta Naresvara Nircela , Umar Mohamad Aulia
Published: April 2020

Bioethanol is considered as the most promising prospective renewable energy source. One of the most potential lignocellulose material for bioethanol feedstock is spent media (SM) of edible mushroom. Pleurotus ostreatus is more selective to degrade lignin than holocellulose component, therefore the SM is very compatible as a bioethanol feedstock. This study was observed the influence of variation of cultivation time of oyster mushroom (P.ostreatus) into the SM chemical content and its ethanol production yield by using simultaneous saccharification and fermentation method. The results showed that the difference of cultivation time did not show the significant result on SM chemical content, except the hot water soluble extractive content. The highest hot water soluble extractive content was found in SM with 110 days of cultivation time (27.68%). The highest hydrolysis rate was found at 90 days of cultivation time (15.65%) and 48 and 72 hours saccharification time (14.77% and 14.78%). The highest reducing sugar content was found at 110 days of cultivation time (4.89 g/L). The highest ethanol content was found in SM with a combination of 90 days cultivation time and 48 hours saccharification time (1.696 g/L). The 90 days cultivation time was enough to produce SM that can be used as raw material for bio-ethanol production.
A craniopharyngioma in a seven-year-old dog
Authors: Eckersley G. N. , Geel Judith K. , Kriek N. P.J.
Published: April 2020

A seven-year-old male Border Collie was presented with a history of lethargy, episodic circling, incoordination and polydypsia. Physical examination revealed depression, obesity and bradycardia. A neurological examination indicated the possible presence of a space-occupying lesion in the brain. Results of the clinical investigation revealed hyposthenuria, sinus bradycardia and increased concentration of protein in the cerebrospinal fluid. A computerised axial tomography scan revealed a mass in the region of the hypophysis. The dog was euthanased and a post mortem examination confirmed the presence of a craniopharyngioma.
Effect of monensin and its metabolites in broiler litter on sheep consuming the broiler litter
Authors: Van Ryssen J. B.J.
Published: April 2020

Two trials were conducted to determine the effect of monensin in broiler litter on sheep receiving the broiler litter in their diets. Broiler litter from chickens fed monensin as a coccidiostat, and from chickens receiving no coccidiostat, was included at a level of 30% in 2 sheep diets. In a further 2 treatments, monensin (15 mg kg-1) was added to each of the 2 diets to give a 2x2 factorial experimental design. In the first trial, copper (20 mg kg-1 feed) was added to the diets. These lambs were fed individually at a slightly restricted level of intake. No differences between treatments were observed in feed intake, average daily gain or efficiency of feed utilisation or in the concentrations of zinc, iron and manganese in the liver, glutathione peroxidase in erythrocytes and creatine kinase concentrations in the. plasma. Hepatic copper content and copper retention in the livers of the sheep receiving the added monensin were signficantly higher (P 0,05 and 0,01 respectively) than in those not receiving added monensin. The aspartate transaminase and alkaline phosphatase concentrations in the plasma of these sheep were also higher (P 0,05) than in those not consuming added monensin. In the second trial, the lambs were group-fed according to treatment and received the diets on an ad lib basis. The mean intakes of the groups receiving the diets with the added monensin, were lower than the intakes by the other groups. It was concluded that the monensin metabolites in broiler litter had no measurable effect on any of the parameters of monensin activity investigated in sheep, when such litter was included in sheep diets.
The seasonal activity of adult ixodid ticks on Angora goats in the south western Orange Free State
Authors: Fourie L. J. , Horak I. G.
Published: April 2020

Adult ixodid ticks were collected at 2-weekly intervals for a period of 23 consecutive months from 15 to 20 Angora goats on a farm in the south western Orange Free State. A total of 6 ixodid tick species were recovered. Rhipicephalus punctatus was the most abundant and prevalent tick, It was present from spring to late summer. Ixodes rubicundus was the next most abundant tick and was present mainly from March or April to July with peak numbers present in April or May. The onset of this tick's activity appeared to be stimulated by low atmospheric temperatures.
Interaction of Plastics with Marine Species
Authors: Ozturk Rafet Cagri , Altinok Ilhan
Published: April 2020

The plastic litter in the seas and oceans has become one of the major threats for environment and a wide range of marine species worldwide. Microplastics are the most common litters in the marine environment corresponding to 60-80% of the total litter in the world’s seas. The risk factor of plastics is inversely associated with the size of the plastic. In the present study, we reviewed the state of knowledge regarding the impact of plastic pollution on marine environment and marine species, assessing the ingestion incidences, elimination of plastics, interactions of plastics with other pollutants, and effects on photosynthesis. Records of marine species ingesting plastic have increased and begin to attract considerable attention. Metadata generated from the review of related papers in the present study was used to evaluate the current knowledge on the plastic ingestion by different marine species. The retrieved data from reviewed articles revealed that the ingestion of plastic by marine animals have been documented in more than 560 species including fish, crustaceans, mammals, sea turtles, bivalves, gastropods even in sea stars and limpets. The size of ingested plastics varied from species to species generally depending on the feeding behavior. Microplastics showed the highest number of bibliographic citations in the plastic ingestion studies. They are mostly ingested by planktivorous and filter feeder species. Meso, macro, and occasionally megaplastics are reported in marine mammals and sea turtles since they often confuse plastic for their prey. The sensitivity and size of the detected plastics may vary based on the analytical plastic detection methods.
Aplicación de la transformada de Hilbert-Huang en el análisis de señales de comunicación satelital
Authors: Villanueva J. , Bueno M. , Simón J. , Molinas M. , Flores J. , Méndez P. E.
Published: April 2020

En los enlaces de comunicación entre satélites y estaciones terrenas, la señal transmitida está expuesta a perturbaciones y ruido de diferentes tipos que dificultan la recepción y recuperación de la información. Por está razón, diferentes métodos son utilizados para procesar la señal recibida y eliminar dichas perturbaciones, y así recuperar la información. Diferentes técnicas de análisis de señales se han utilizado para lograr lo anteriormente descrito pero los resultados no son completamente satisfactorios. La Transformada de Hilbert Huang ha venido aplicándose cada vez más en diferentes áreas y las señales satelitales no son la excepción. En este trabajo, se realiza el análisis mediante la Transformada de Hilbert Huang de una señal de comunicación satelital que presenta ruido gausiano; el propósito es eliminar las perturbaciones del ruido y poder recuperar la señal transmitida. La estrategia propuesta es comparada con la Transformada Rápida de Fourier la cual normalmente es usada para estas aplicaciones. Algunos resultados con señales simuladas y reales son mostradas para validar la metodología.
Sintonización del controlador en cascada PI-STA para aplicaciones de filtros activos de potencia
Authors: Terán R. , Pérez J. , Beristáin J. , Cárdenas V.
Published: April 2020

Típicamente el esquema de control de un filtro activo de potencia corresponde a un controlador en cascada, el cual consta de un lazo externo para la regulación del voltaje de cd y un lazo interno para el seguimiento de una corriente de referencia. Cada uno de estos lazos de control está asociado a un controlador que permite converger rápidamente a su respectiva referencia. Este trabajo emplea un controlador PI en el lazo externo y el algoritmo Super-Twisting (STA) en el lazo interno, los cuales conforman al controlador en cascada denotado como PI-STA. Este artículo presenta una metodología para sintonizar los controladores PI y STA, donde el primero se sintoniza a partir de la respuesta al escalón, mientras el STA se sintoniza a partir de considerar la similitud de su estructura con respecto a la de un PI, facilitando así la obtención de las ganancias del STA. Para validar la metodología de sintonización, se presentan resultados en simulación y experimentales.
Uma pesquisa em movimento: crianças, terra, minhocas e... mãos à horta
Authors: Pérez Carmen Lúcia Vidal
Published: April 2020

Afirmamos um modo de pesquisar com as crianças fundado na ‘epistemologia da escuta’ - uma atitude investigativa que envolve o estar à escuta, atenta as complexas relações entre o ouvir e o entender. Buscamos ouvir as crianças em outros registros, atentas ao seu dizer singular que coloca os sentidos instalados em ‘estado de borda’ e tecem encontros inventivos na Creche UFF - locus da presente investigação. Narramos a experiência de construção da horta da Creche UFF, coletivamente vivida com crianças de 2 (dois) a 6 (seis) anos e estudantes de graduação do Curso de Pedagogia-UFF. A pesquisa tem como foco os acontecimentos vividos pelas crianças e, os processos pedagógicos inventados na construção da Horta da Creche. Os resultados obtidos nos permitem compreender o ato de conhecer como experiência intensa que mobiliza emoções e desejos. Afirmamos a curiosidade espontânea da criança como potencializadora de novos conhecimentos pelo exercício da ‘curiosidade epistemológica’ e defendemos uma educação infantil dialógica e democrática.
Trends and emissions of six perfluorocarbons in the Northern Hemisphere and Southern Hemisphere
Authors: Droste Elise S. , Adcock Karina E. , Ashfold Matthew J. , Chou Charles , Fleming Zoë , Fraser Paul J. , Gooch Lauren J. , Hind Andrew J. , Langenfelds Ray L. , Leedham Elvidge Emma C. , Mohd Hanif Norfazrin , O'Doherty Simon , Oram David E. , Ou-Yang Chang-Feng , Panagi Marios , Reeves Claire E. , Sturges William T. , Laube Johannes C.
Published: April 2020

Abstract. Perfluorocarbons (PFCs) are potent greenhouse gases with global warming potentials up to several thousand times greater than CO2 on a 100-year time horizon. The lack of any significant sinks for PFCs means that they have long atmospheric lifetimes of the order of thousands of years. Anthropogenic production is thought to be the only source for most PFCs. Here we report an update on the global atmospheric abundances of the following PFCs, most of which have for the first time been analytically separated according to their isomers: c-octafluorobutane (c-C4F8), n-decafluorobutane (n-C4F10), n-dodecafluoropentane (n-C5F12), n-tetradecafluorohexane (n-C6F14), and n-hexadecafluoroheptane (n-C7F16). Additionally, we report the first data set on the atmospheric mixing ratios of perfluoro-2-methylpentane (i-C6F14). The existence and significance of PFC isomers have not been reported before, due to the analytical challenges of separating them. The time series spans a period from 1978 to the present. Several data sets are used to investigate temporal and spatial trends of these PFCs: time series of air samples collected at Cape Grim, Australia, from 1978 to the start of 2018; a time series of air samples collected between July 2015 and April 2017 at Tacolneston, UK; and intensive campaign-based sampling collections from Taiwan. Although the remote “background” Southern Hemispheric Cape Grim time series indicates that recent growth rates of most of these PFCs are lower than in the 1990s, we continue to see significantly increasing mixing ratios that are between 6 % and 27 % higher by the end of 2017 compared to abundances measured in 2010. Air samples from Tacolneston show a positive offset in PFC mixing ratios compared to the Southern Hemisphere baseline. The highest mixing ratios and variability are seen in air samples from Taiwan, which is therefore likely situated much closer to PFC sources, confirming predominantly Northern Hemispheric emissions for most PFCs. Even though these PFCs occur in the atmosphere at levels of parts per trillion molar or less, their total cumulative global emissions translate into 833 million metric tonnes of CO2 equivalent by the end of 2017, 23 % of which has been emitted since 2010. Almost two-thirds of the CO2 equivalent emissions within the last decade are attributable to c-C4F8, which currently also has the highest emission rates that continue to grow. Sources of all PFCs covered in this work remain poorly constrained and reported emissions in global databases do not account for the abundances found in the atmosphere.
Understanding Processes that Control Dust Spatial Distributions with Global Climate Models and Satellite Observations
Authors: Wu Mingxuan , Liu Xiaohong , Yu Hongbin , Wang Hailong , Shi Yang , Yang Kang , Darmenov Anton , Wu Chenglai , Wang Zhien , Luo Tao , Feng Yan , Ke Ziming
Published: April 2020

Abstract. Dust aerosol is important in modulating the climate system at local and global scales, yet its spatiotemporal distributions simulated by global climate models (GCMs) are highly uncertain. In this study, we evaluate the spatiotemporal variations of dust extinction profiles and dust optical depth (DOD) simulated by the Community Earth System Model version 1 (CESM1) and version 2 (CESM2), the Energy Exascale Earth System Model version 1 (E3SMv1), and the Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2) against satellite retrievals from Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), Moderate Resolution Imaging Spectroradiometer (MODIS), and Multi-angle Imaging SpectroRadiometer (MISR). We find that CESM1, CESM2, and E3SMv1 underestimate dust transport to remote regions. E3SMv1 performs better than CESM1 and CESM2 in simulating dust transport and the northern hemispheric DOD due to its higher mass fraction of fine dust. CESM2 performs the worst in the northern hemisphere due to its lower dust emission than in the other two models but has a better dust simulation over the Southern Ocean due to the overestimation of dust emission in the southern hemisphere. DOD from MERRA-2 agrees well with CALIOP DOD in remote regions due to its higher mass fraction of fine dust and the assimilation of aerosol optical depth. The large disagreements in the dust extinction profiles and DOD among CALIOP, MODIS, and MISR retrievals make the model evaluation of dust spatial distributions challenging. Our study indicates the importance of representing dust emission, dry/wet deposition, and size distribution in GCMs in correctly simulating dust spatiotemporal distributions.
Effects of global ship emissions on European air pollution levels
Authors: Jonson Jan Eiof , Gauss Michael , Schulz Michael , Jalkanen Jukka-Pekka , Fagerli Hilde
Published: April 2020

Abstract. Ship emissions constitute a large, and so far poorly regulated, source of air pollution. Emissions are mainly clustered along major ship routes, both in open seas and close to densely populated shorelines. Major air pollutants emitted include sulfur dioxide, NOx and particles. Sulfur dioxide and NOx are both major contributors to the formation of secondary fine particles (PM2.5) and to acidification and eutrophication. In addition, NOx is a major precursor for ground-level ozone. This study is based on global and regional model calculations. The model runs are made with meteorology and emission data representative for year 2017, after the tightening of the SECA (Sulphur Emission Control Area) regulations in 2015, but before the global sulfur cap entering into force in 2020. We have also made model runs reducing sulfur emissions by 80 % corresponding to the 2020 requirements. This study is based on model sensitivity studies perturbing emissions from different sea areas: the Northern European SECA in the North Sea and the Baltic Sea, the Mediterranean Sea and the Black Sea, the Atlantic Ocean close to Europe, shipping in the rest of the world and finally all global ship emissions together. Sensitivity studies have also been made setting lower bounds on the effects of ship plumes on ozone formation. The results from the global and regional calculations are similar. Both global and regional scale calculations show that for PM2.5 and depositions of oxidised nitrogen and sulfur, the effects of ship emissions are much larger when emissions occur close to the shore than at open seas. In many coastal countries calculations show that shipping is responsible for 10 % or more of the controllable PM2.5 concentrations and depositions of oxidised nitrogen and sulphur. For ozone the lifetime in the atmosphere is much longer than for PM2.5, and the potential for ozone formation is much larger in otherwise pristine environments. We find considerable contributions from open sea shipping. As a result the largest contributions to ozone in several regions and countries are from rest of the world shipping.
Timing of drought in the growing season and strong legacy effects determine the annual productivity of temperate grasses in a changing climate
Authors: Hahn Claudia , Ernst-Hasler Sara , Lüscher Andreas , Kahmen Ansgar
Published: April 2020

Abstract. The frequency of extreme weather events, such as droughts, is assumed to increase leading to alterations of ecosystem productivity and thus the terrestrial carbon cycle. Although grasslands typically show reduced productivity in response to drought, their effects have been shown to vary quite dramatically. Here we tested in a two-year field experiment, if the resistance and the resilience of grasses towards drought varies throughout a growing season and if the timing of drought, thus, influences drought-induced reductions in annual net primary production (NPP) of grasses. For the experiment we grew six temperate and perennial C3 grass species in a field as monocultures. The grasses were cut six times during the growing season and subject to 10-week drought treatments that occurred either in the spring, the summer or the fall. Across all species, drought-induced losses of productivity were smaller (−20 % to −51 %) than in summer and fall (−77 % to −87 %). This suggests a higher resistance to drought in spring when the productivity of the grasses is the highest and plants are in their reproductive stage. After the release of drought, we found no prolonged suppression of growth. In contrast, post-drought growth rates of formerly drought-stressed swards outperformed the growth rates of the control swards. In 2014, the overcompensation after drought release was similar in all seasons, but differed in 2015. The strong overcompensation of growth after drought release resulted in relatively small overall drought-induced losses of annual ANPP that ranged between −4 % to −14 % and were not affected by the timing of the drought event. Our results show that (i) the resistance of growth rates in grasses to drought varies across the season and is positively correlated with growth rates in the control, (ii) that positive legacy effects of drought indicate a high resilience of temperate grasses to drought, and (iii) that the high resilience can compensate immediate drought effects on total annual biomass production to a large extent.
Reconstructing the Evolution of Ice Sheets, Sea Level and Atmospheric CO2 During the Past 3.6 Million Years
Authors: Berends Constantijn J. , de Boer Bas , van de Wal Roderik S. W.
Published: April 2020

Abstract. Understanding the evolution of, and the interactions between, ice sheets and the global climate over geological time is important for being able to constrain earth system sensitivity. However, direct observational evidence of past CO2 concentrations only exists for the past 800 000 years. Records of benthic δ18O date back millions of years, but contain signals from both land ice volume and ocean temperature. In recent years, inverse forward modelling has been developed as a method to disentangle these two signals, resulting in mutually consistent reconstructions of ice volume, temperature and CO2. We use this approach to force a hybrid ice-sheet – climate model with a benthic δ18O stack, reconstructing the evolution of the ice sheets, global mean sea level and atmospheric CO2 during the late Pliocene and the Pleistocene, from 3.6 million years (Myr) ago to the present day. During the warmer-than-present climates of the Late Pliocene, reconstructed CO2 varies widely, from 320–440 ppmv for warm periods such as Marine Isotope Stage (MIS) KM5c, to 235–250 ppmv for the MIS M2 glacial excursion. Sea level is relatively stable during this period, with a high stand of 6–14 m, and a drop of 12–26 m during MIS M2. Both CO2 and sea level are within the wide ranges of values covered by available proxy data for this period. Our results for the Pleistocene agree well with the ice-core CO2 record, as well as with different available sea-level proxy data. During the early Pleistocene, 2.6–1.2 Myr ago, we simulate 40 kyr glacial cycles, with interglacial CO2 decreasing from 280–300 ppmv at the beginning of the Pleistocene, to 250–280 ppmv just before the Mid-Pleistocene Transition (MPT). Peak glacial CO2 decreases from 220–250 ppmv to 205–225 ppmv during this period. After the MPT, when the glacial cycles change from 40 kyr to 80/120 kyr cyclicity, the glacial-interglacial contrast increases, with interglacial CO2 varying between 250–320 ppmv, and peak glacial values decreasing to 170–210 ppmv.
ARIOS: An acidification ocean database for the Iberian Upwelling Ecosystem
(1976–2018)
Authors: Padin Xosé Antonio , Velo Antón , Pérez Fiz F.
Published: April 2020

Abstract. A data product of 17,653 discrete samples from 3,357 oceanographic stations combining measurements of pH, alkalinity and other biogeochemical parameters off the North-western Iberian Peninsula from June 1976 to September 2018 is presented in this study. The oceanography cruises funded by 24 projects were primarily carried out in the Ría de Vigo coastal inlet, but also in an area ranging from the Bay of Biscay to the Portuguese coast. The robust seasonal cycles and long-term trends were only calculated along a longitudinal section, gathering data from the coastal and oceanic zone of the Iberian Upwelling System. The pH in the surface waters of these separated regions, which were highly variable due to intense photosynthesis and the remineralization of organic matter, showed an interannual acidification ranging from −0.0016 yr−1 to −0.0032 yr−1 that grew towards the coastline. This result is obtained despite the buffering capacity increasing in the coastal waters further inland as shown by the increase in alkalinity by 1.1±0.7 μmol kg−1 yr−1 and 2.6±1.0 μmol kg−1 yr−1 in the inner and outer Ría de Vigo respectively, driven by interannual changes in the surface salinity of 0.0193±0.0056 psu yr−1 and 0.0426±0.016 psu yr−1 respectively. The loss of the vertical salinity gradient in the long-term trend in the inner ria was consistent with other significant biogeochemical changes such as a lower oxygen concentration and fertilization of the surface waters. These findings seem to be related to a growing footprint of sediment remineralization of organic matter in the surface layer of a more homogeneous water column. Data are available at: https://doi.org/10.20350/digitalCSIC/12498 (Pérez et al., 2020).
HR3DHG version 1: modeling the spatiotemporal dynamics of mercury in the Augusta Bay (southern Italy)
Authors: Denaro Giovanni , Salvagio Manta Daniela , Borri Alessandro , Bonsignore Maria , Valenti Davide , Quinci Enza , Cucco Andrea , Spagnolo Bernardo , Sprovieri Mario , De Gaetano Andrea
Published: April 2020

Abstract. The biogeochemical dynamics of Hg, and specifically of its three
species Hg0, HgII, and MeHg (elemental, inorganic, and
organic, respectively), in the marine coastal area of Augusta Bay
(southern Italy) have been explored by the high-resolution 3D Hg
(HR3DHG) model, namely an advection–diffusion–reaction model for
dissolved mercury in the seawater compartment coupled with a
diffusion–reaction model for dissolved mercury in the pore water of
sediments in which the desorption process for the sediment total mercury is taken into account. The spatiotemporal variability of the mercury concentration in both seawater ([HgD])
and the first layers of bottom sediments ([HgDsed] and
[HgTsed]), as well as the Hg fluxes at the boundaries of the 3D
model domain, have been theoretically reproduced, showing acceptable agreement with the experimental data collected in
multiple field observations during six different oceanographic
cruises. Also, the spatiotemporal dynamics of the total mercury concentration in seawater have been obtained by using both model results and field observations. The mass balance of the total Hg species in seawater has been calculated for the Augusta Harbour, improving previous estimations. The HR3DHG model could be used as an effective tool to predict the spatiotemporal distributions of dissolved and total mercury concentrations, while contributing to better assessing hazards for the environment and therefore for human health in highly polluted areas.
Non-stationary analysis of water level extremes in Latvian waters, Baltic Sea, during 1961–2018
Authors: Kudryavtseva Nadezhda , Soomere Tarmo , Männikus Rain
Published: April 2020

Abstract. Analysis and prediction of water level extremes in the eastern Baltic Sea is a difficult task because of the contribution of various drivers to the water level, the presence of outliers in time series and possibly non-stationarity of the extremes owing to the changes in the atmospheric forcing. Non-stationary modelling of extremes was performed to the block maxima of water level derived from the time series at six locations in the Gulf of Riga and one location in the Baltic proper, Baltic Sea, during 1961–2018. Several parameters of the Generalised Extreme Value distribution of the measured water maxima both in the Baltic proper and in the interior of the Gulf of Riga exhibit statistically significant changes over these years. The most considerable changes occur to the shape parameter ξ. All stations in the interior of the Gulf of Riga experienced a regime shift: a drastic abrupt drop of the shape parameter from ξ ≈ 0.03 ± 0.02 to ξ ≈ −0.36 ± 0.04 around 1986 followed by an increase of a similar magnitude around 1990. This means a sudden switch from a Fréchet distribution to a three-parameter Weibull distribution and back. The water level extremes at Liepaja in the Baltic proper and Kolka at the entrance to the Gulf of Riga reveal significant linear trends in the location and scale parameters. This pattern indicates a different course of the water level extremes in the Baltic proper and the interior of the Gulf of Riga. The described changes may lead to greatly different projections for long-term behaviour of water level extremes and their return periods based on data from different intervals.
Satellite observations of unprecedented phytoplankton blooms in the Maud Rise polynya, Southern Ocean
Authors: Jena Babula , Pillai Anilkumar N.
Published: April 2020

Abstract. The appearance of phytoplankton blooms within sea ice cover is of high importance considering the upper ocean primary production that
controls the biological pump, with implications for atmospheric CO2
and global climate. Satellite-derived chlorophyll a concentration showed
unprecedented phytoplankton blooms in the Maud Rise polynya, Southern Ocean,
with chlorophyll a reaching up to 4.67 mg m−3 during 2017.
Multi-satellite data indicated that the bloom appeared for the first time since
the entire mission records started in 1978. An Argo float located in the
polynya edge provided evidence of bloom conditions in austral spring 2017
(chlorophyll a up to 5.47 mg m−3) compared to the preceding years with
prevailing low chlorophyll a. The occurrence of bloom was associated with the
supply of nutrients into the upper ocean through Ekman upwelling (driven
by wind stress curl and cyclonic ocean eddies) and improved light conditions of
up to 61.9 einstein m−2 d−1. The net primary production from the
Aqua Moderate Resolution Imaging Spectroradiometer chlorophyll-based
algorithm showed that the Maud Rise polynya was as productive as the
Antarctic coastal polynyas, with carbon fixation rates reaching up to
415.08 mg C m−2 d−1. The study demonstrates how the
phytoplankton in the Southern Ocean (specifically over the shallow
bathymetric region) would likely respond in the future under warming
climate conditions and continued melting of Antarctic sea ice.
Repertorios interpretativos de un manual de intervención en la infancia temprana en Chile
Authors: Calquin Donoso Claudia , Guerra Arrau Rodrigo , Escobar Villalobos Katherine , Martinez Riquelme Javier
Published: April 2020

Si bien los estudios de gubernamentalidad se han erigido como una alternativa teórica y metodológica relevante para estudiar las políticas sociales, son pocos los trabajos que se han dedicado a estudiar las políticas específicas en la infancia. Como una forma de aportar a la investigación sobre la relación entre gubernamentalidad e infancia, se presentan los resultados de una investigación dirigida a conocer los repertorios interpretativos de un manual de atención psicosocial en el sistema de protección de la infancia en Chile. La metodología consistió en un análisis discursivo del cuerpo del manual basado en la perspectiva de los repertorios interpretativos. Se identificaron cuatro repertorios: 1) cimientos de lo social: la relación como actor; 2) el Estado como agente de racionalidad y salvación nacional; 3) la operación del manual: el Estado como coach, y finalmente 4) la figura de la madre: del sujeto en riesgo al sujeto de riesgo. Se concluye que la producción discursiva de la infancia opera por medio de prácticas discursivas cuya función es su despolitización, bajo grillas interpretativas de corte naturalístico que opacan las relaciones de poder, económicas y de saber que cruzan la pobreza infantil y las tensiones entre el saber científico y el saber empírico de las madres.
El papel de las mujeres en los acuerdos de paz en Colombia: la agenda internacional
Authors: Garrido Ortolá Anabel
Published: April 2020

Los acuerdos de paz en Colombia se han conformado como un referente internacional al poner fin a cincuenta y nueve años de conflicto armado en el país e incorporar nuevos instrumentos jurídicos que establece el marco sobre Mujer, Paz y Seguridad de Naciones Unidas. Así pues, esta transformación sobre las narrativas de la securitización está mediada por los relatos de las organizaciones de mujeres, que, junto con la Resolución 1325 del Consejo de Seguridad, han promovido su mayor participación en los procesos de negociación, así como la incorporación de un enfoque de género en los acuerdos de paz, logrando así romper con un espacio inicialmente masculinizado. A partir del examen de los distintos acuerdos de paz acontecidos en Colombia y las dinámicas de género que los atraviesan, el artículo evidencia cómo se ha logrado un cambio en las narrativas de género establecido en el discurso hegemónico, y cómo, en consecuencia, las mujeres se convierten en sujetos políticos necesarios para la consecución de la paz en Colombia.
La sostenibilidad de la vivienda: razones para incentivar su desarrollo en España
Authors: Lambea Rueda Ana , Grau Ruiz María Amparo , Pastor Albaladejo Gema
Published: April 2020

En el marco de los Objetivos de Desarrollo Sostenible de la Agenda 2030 (en particular en el Objetivo número 11 sobre Ciudades y Comunidades Sostenibles) se aprobó la Directiva 2018/844 UE de 30 de mayo, modificando las anteriores 2010/31 de eficiencia energética de edificios y 2012/27 de eficiencia energética, para lograr "un parque inmobiliario descarbonizado y altamente eficiente (…) para transformar los edificios existentes en edificios de consumo de energía casi nulo... con una renovación a una tasa media anual del 3% (...) aplicando las Directrices de la OMS sobre la calidad de aire interior… y apoyando medidas de fomento de financiación inteligente para edificios inteligentes de la Comisión Europea". La Directiva anuncia una mejora de la transparencia de los certificados de eficiencia energética, garantizando el establecimiento y la aplicación uniformes de todos los parámetros de cálculo necesarios, tanto por lo que respecta a la certificación como a los requisitos mínimos de eficiencia energética, y propone un sistema de control posterior automatizado y electrónico. En el marco del proyecto del Plan nacional de I+D+i CertificaRSE5, se han analizado la certificación, las eco-etiquetas y el apoyo necesario con recursos financieros públicos para impulsar el futuro del sector. Para obtener esta información, se ha optado por diseñar y aplicar una técnica de investigación cuantitativa. En concreto, se ha realizado una encuesta a los grupos de interés del sector de la edificación y rehabilitación, por su experiencia con el manejo de certificaciones y su impacto real en la sostenibilidad. Se ha invitado a los encuestados a valorar la introducción de nuevos incentivos en los impuestos aplicables al sector de construcción y rehabilitación de viviendas, ajustados al retorno en sostenibilidad que generan, con el propósito de mejorar la normativa y la comunicación de todos los agentes involucrados con la sociedad. La finalidad de esta encuesta ha sido valorar la adecuación del marco normativo y financiero a la hora de atender las necesidades existentes, por lo que se han tenido en cuenta diferentes dimensiones analíticas: la sostenibilidad en el sector, la certificación, los recursos económicos y financieros, la normativa aplicada y la comunicación con agentes del sector y con la sociedad.
Determinantes de la calidad de la información divulgada vía Web por las pequeñas y medianas cooperativas de Canarias
Authors: González Aponcio Zenona
Published: April 2020

El avance experimentado por las tecnologías de información, y en concreto el desarrollo de las tecnologías de Internet, ha tenido su máximo exponente en el despliegue progresivo de servicios y aplicaciones para las empresas, provocando que las pymes reaccionen ante la transformación digital de los negocios para adaptarse a las nuevas exigencias. Dentro de este grupo de empresas hay cooperativas que se enfrentan con mercados que requieren concepciones personalizadas y flexibles del producto o servicio. Ante estas exigencias, las cooperativas han de conectar con el entorno para captar las necesidades de clientes y socios, y obtener información que ayude a satisfacerlos. Para ello, resulta fundamental dotarse de sitios Web corporativos que generen información y conocimiento de apoyo al proceso de toma de decisiones y anticiparse a los cambios. El objetivo de este trabajo es conocer cuáles son los indicadores que explican la calidad de la información que divulgan las pequeñas y medianas cooperativas de Canarias a través del sitio Web corporativo. Para lograrlo, se basa en el modelo de Delone y McLean (2002 y 2003) adaptado a los sitios Web de 24 cooperativas que se identifican utilizando la base de datos SABI y cuyos datos se analizan aplicando el Modelo de Rasch (1980). Los resultados se corresponden con el total de cooperativas que tienen sitio Web activo y revelan que la calidad de la información que comparten las cooperativas mediante el sitio se basa más en información sobre los productos e información útil que en información para los socios y clientes, y algunos indicadores están condicionados por la provincia donde se localizan y el período en que se crean. Por consiguiente, conviene que las cooperativas no sólo valoren el mantener un sitio Web corporativo para compartir información completa, actualizada, relevante y exacta, sino también para comunicarse y realizar transacciones con los socios y los clientes que satisfagan sus necesidades y expectativas. Las conclusiones obtenidas demuestran que, en general, las pequeñas y medianas cooperativas seleccionadas usan sitios Web estáticos y estructurados sin que hayan evolucionado hacia portales empresariales, y que desaprovechan la información que pueden recoger del sitio para predecir e interpretar comportamientos de socios y clientes, así como para ofrecer productos y servicios ajustados a sus preferencias.
Tertiary Anatomy and Physiology, A Barrier for Student Success
Authors: Vitali Julian , Blackmore Conner , Mortazavi Siavash , Anderton Ryan
Published: April 2020

Anatomy and physiology courses are a foundation for numerous degrees, but experience some of the highest failure rates of all undergraduate health science programs (Higgins-Opitz & Tufts, 2014). While interventions have been developed in an attempt to remediate this concerning phenomenon, there is a paucity of evidence to determine the reason anatomy and physiology courses pose such an obstacle to students, and whether there are reliable early determinants for student success in these courses. This review will discuss why this obstacle exists, and the factors that contribute to success and failure in undergraduate anatomy and physiology courses.
An Emerging Credit Risk Framework
Authors: Vlachostergios Eleftherios
Published: April 2020

The main result of this paper is the establishment of an analytic formula for the estimation capital requirements of an individual loan.

The derived formula, may be considered as a direct analogue to the Basel risk-weight functions for credit risk, first presented in Basel II framework, with the additional advantage of utilizing a lifetime horizon, thus being suitable for IFRS9/GAAP purposes. Essentially, it bridges the gap between Basel and IFRS9 frameworks as:

The 1-year horizon incorporated in the Basel PD is extended up to maturity, following the IFRS9 rationale;

The notion of unexpected losses, already supplied by Basel Framework, is added to the IFRS9 logic in an analytic fashion.

Going one step further, the generalization of the risk variables used in the formula, as Kumaraswamy identically distributed variables, allows for the benchmarking of the total loss of a credit portfolio, with the single knowledge of its current non-performing loans percentage.

This conclusion is successfully verified against EBA stress test results for the period 2018-2020.
Rapid TB diagnostic service and community action to FIND.TREAT.ALL#EndTB, Maputo, Mozambique, 2013–2018
Authors: Burny R. , Manhiça I. , de Abreu A. Pedro Magaia , De Castro S. Lobo , Manhique J. , Fiebig L. , Valverde E.
Published: April 2020

Finding and treating all tuberculosis (TB) patients is crucial for ending TB. We investigated whether rapid diagnostic turnaround time (TAT) and patient tracking could increase TB treatment initiation in Maputo, Mozambique. Among 3329 TB patients newly diagnosed by the University Eduardo
Mondlane-Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling/Anti-Personnel Landmines Detection Product Development (APOPO) Laboratory between 2013 and 2018, on average 61% were verifiably linked to care. This proportion increased from 54% (first half 2013) to 79% (second half 2018) after
introducing a 24-hour TAT in 2015 and patient tracking conducted by a community-based partner, Associação Kenguelekezé, in 2017. Rapid, well-connected TB diagnostic services can reduce pre-treatment loss to follow-up and support the joint initiative of WHO, Stop TB and
Global Fund to ‘FIND.TREAT.ALL.#EndTB’.
Improving sputum collection processes to increase tuberculosis case finding among HIV-positive persons in Botswana
Authors: Mathebula U. , Emerson C. , Agizew T. , Pals S. , Boyd R. , Mathoma A. , Basotli J. , Rankgoane-Pono G. , Serumola C. , Date A. , Auld A. F. , Finlay A.
Published: April 2020

Setting: Twenty-two human immunodeficiency virus (HIV) clinics in Botswana.Objective: To compare sputum collection rates, sputum quality and volume, and tuberculosis (TB) diagnosis rates before and after field efforts to improve sputum collection among individuals
newly diagnosed with HIV with TB symptoms.Design: Newly diagnosed individuals living with HIV attending 22 HIV clinics in Botswana were screened for TB from August 2012 to March 2014. Starting in May 2013, a field intervention composed of the introduction of a tracking log for presumed
TB patients, and patient instructions and sputum induction to improve sputum collection rates was implemented.Results: Prior to the intervention, sputum collection rates were 44.1% (384/870). Subsequently, sputum collection increased to 58.3% (579/993) (P < 0.001). Sputum
quality and volume also improved. Although rates of TB diagnosis increased from 9.7% (84/870) to 12.5% (120/993), this difference was not significant (P = 0.143).Conclusion: Sputum collection rates among presumptive TB cases, as well as sputum quality and volume improved
after implementation of the field intervention. To improve sputum collection rates, efforts at the program level should be ongoing.
Review of the book "Fatherhood and its views", edited by Fr. Janusz Mastalski, priest Grzegorz Godawa, Katarzyna Kutek-Sładek, Łukasz Ryszka, Kraków 2018, p. 232
Authors: Ahapau Andrei
Published: April 2020

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Pre-school and early-school education. Selected problems, edited by K. Pujer, Wrocław 2016, pp. 144, ISBN: 978-83-65374-10-3
Authors: Ahapau Andrei
Published: April 2020

Review