Is there an expiration effect in the bitcoin market?

This paper studies the monthly expiration effect in the bitcoin markets. The emergence of trading in bitcoin futures in regulated markets is an ideal occasion to test this effect on an asset with singular characteristics. Our results with intraday data show that around the time of maturity there are significant changes in the trading volume, volatility and return of bitcoin, an asset that is traded in many exchanges simultaneously. Therefore, there is a clear expiration effect related to bitcoin futures. The closer to the expiration time (shortly beforehand or afterwards), the more intense these effects are. However, in spite of these general results, the expiration effect is not homogeneous across exchanges and depends on the characteristics of the futures contract in question. Robustness tests are also applied to confirm the results. The increasing participation of institutional investors is consistent with our findings, particularly in relation to the expiration effects of cash-settled futures, as these contracts are more appealing for sophisticated investors who could be interested in arbitrage or speculative processes.Grant PID2019-104304GB-I00 funded by MCIN/AEI /10.13039/501100011033 https://doi.org/10.13039/501100011033 ; Grant RTI2018-093483-B-I00 funded by MCIN/AEI /10.13039/501100011033 https://doi.org/10.13039/501100011033 and by ERDF A way of making Europe; Grant S11_20R: Cembe funded by the Government of Aragon and ERDF

Evidence of jaagsiekte sheep retrovirus-induced pulmonary adenocarcinoma in Ouled Djellal breed sheep in Algeria

We report the occurrence of lung cancer in a six months old lamb of Ouled Djellal breed from Algeria. The main clinical sign was a considerable amount of whitish foamy fluid discharge from the nostrils when the animal head was lowered and the rear end was lifted. The postmortem examination revealed the presence of enlarged, heavy and edematous lungs with diffuse or foci areas, reddish or white-gray in color. The gross and histological lesions of the lungs were compatible with pulmonary adenocarcinoma. Lung adenocarcinoma in sheep is caused by jaagsiekte sheep retrovirus (JSRV) and originated from differentiated alveolar type II cells and non-ciliated bronchiolar epithelial Clara cells. We evidenced the expression of the oncogenic JSRV by immunostaining of lung slides with specific antibodies against the JSRV envelope. The viral proteins were expressed only in the tumor cells from the affected areas. As already described in other countries, JSRV-induced lung adenocarcinoma is present in the sheep population in Algeria. (C) 2020 Urmia University. All rights reserved

Cartography of Landscape Dynamics in Central Spain

Depto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasTRUEMinisterio de Educación y Ciencia (MEC)pu

Electrochemical regeneration of a graphite adsorbent loaded with Acid Violet 17 in a spouted bed reactor

A novel spouted bed reactor is evaluated for water treatment by an adsorption and electrochemical regeneration process. The adsorbent is a bisulphate graphite intercalation compound with low specific surface area but high electrical conductivity, suitable for adsorption of contaminants and simultaneous electrochemical regeneration within a single unit. The effects of current density and liquid flow rate on Acid Violet 17 removal were investigated. The hydrodynamic behavior of the liquid spouted bed reactor was characterized by a flow regime map. A four-parameter model has been developed to describe the adsorption and electrochemical regeneration process in the liquid spouted bed reactor. It was found that the experimental data of dye removal agrees well with the modelled simulations

Breves apuntes sobre algunos objetos prehistóricos de la provincia de Santander ; estudio y traducciones al inglés, francés y portugués

Vol I : Breves apuntes sobre algunos objetos prehistóricos de la provincia de Santander ; Vol II : Breves apuntes sobre algunos objetos prehistóricos de la provincia de Santander : traducciones al inglés, francés y portugués.Las h. de lám. pleg. representan pinturas y objetos prehistórico

The Response of Badland Materials from Spain with Different Mineralogical Content on Seasonal Changes

Badlands are areas with limited vegetation, reduced or no human activity, and a great variety of geomorphic processes [1]. Badland materials have a different responsetothe same environmental conditions, because of differences in their mineralogical and physico-chemical characteristics. Many studies show that smectite-poorsediments are more resistant to different weathering treatments of freezing, thawing, wetting, and drying,than smectite-rich materials [2,3].In this paper, three unweathered samples of badlands from Spain were analyzed with the aim of monitoring, but also comparing physico-chemical changes caused by simulations of changes in climatic conditions. Selectedsediment samples havedifferent compositions. Besides quartz and calcite, the first sampleis composed of smectite and gypsum (3 UW), the second of smectite (4 UW), while the third sample is composed of neither smectite nor gypsum (5 UW). The experiment setup was designed in the way that each sample had three sub-samples, a sample for simulation of rain, snow, and a control sample (Figure 1). Sample_rain was treated with a rain intensity of ~850 ml/h for 10 minutes (~140 ml), while sample_snow was treated with crushed ice (~150 g). After precipitation simulations snow were put samples were placed in a climate chamber at - 3 °C together with a control sample. This was repeated for 15 cycles. Every cycle was documented with photographs. The leached solution was collected and its volume, pH, electrical conductivity (EC), and ion concentrations were measured. The second part of the experiment was based on exposing the samples after wetting to higher temperatures, 50 ° C. It was done in 8 cycles. FESEM and BET analyzes were performed for each sample before and after the experiments.The 3 UW samples had significantly different leachate pH and EC, while the leachate volume was similar for all samples during the experiment. Sulphate ions were leached in the highest concentrations during the whole experiment from the sample with both smectite and gypsum present. The sample with smectite has shown the highest disintegration of the structure, especially after the simulation of snow. The sample with smectite and gypsum has shown a lower degree of degradation than sample 3 UW due to the content of gypsum which increases the weathering resistance of the material. Sample 5 UW has shown the lowest degradation of the structure along with the weathering cycles. This study has proven that both mineralogical and physico-chemical properties of sediments are important for predicting their response to variable climate factors

Distribution area of Juniperus oxycedrus L. in Central Spain (Madrid)

The Iberian populations of Juniperus oxycedrus L. subsp. oxycedrus have been studied by several authors who consider their condition as unfavourable. In the Madrid Region, current status, dynamic and distribution area are unknown even when their populations, specifically those who form arborescent shrubs, are included in the type 5210 (Habitat Directive 92/43/EEC). These formations are developed in austere Mediterranean mountain typical of agro ecosystems of high value that have interesting dynamics of recolonization, especially in those areas where agricultural and livestock systems have suffered a setback. This study aims to understand the distribution of juniper in the region of Madrid as the first step to identify and assess the dynamic changes in recent decades. To update the cartography of this species the available information has been checked and completed with photointerpretation and fieldwork. Based on this cartography and the information relating to the physical and biotic variables four types of juniper were differentiated by multivariate methods. On the other hand, two types of dynamics were recognized and it was studied in depth the genesis of changes produced in these forests in the last decades