Correlated response in early embryonic development in rabbits selected for litter size variability

[EN] A divergent selection experiment for litter size variability was carried out in rabbits. The litter size variability was estimated as the phenotypic variance of litter size within female. The aim of this study was to assess the effect of selecting for litter size variability on early embryonic development and survival after 7 generations of divergent selection (high and low variability lines). A total of 30 non-lactating multiparous does per line were used. The ovulation rate and early embryonic development were analysed using Bayesian methodology. Ovulation rate was not affected by the selection process. At 28 h of gestation, embryonic development and survival were similar in both lines. At 48 h of gestation, the majority of embryos in the high line were in the early morulae stage. The high line had a higher proportion of early morulae (79.54 vs. 53.43%; P=0.94) and a lower proportion of compacted morulae (20.46 vs. 46.57%; P=0.93%) than the low line. At 72 h of gestation, the high line had 1.59 fewer embryos than the more homogeneous line (P=0.85), due to reduced embryonic survival (0.60 vs. 0.74; P=0.93). The high line continued to show a higher proportion of early morulae (21.01 vs. 3.69%; P=0.93) and a lower proportion of compacted morulae and blastocysts (78.99 vs. 96.31%; P=0.94) than the low line at 72 h of gestation, indicative of reduced embryonic development. In conclusion, selection for homogeneity in litter size had a positive impact on embryonic traits.This study was financed by the Spanish Ministry of Economy and Competitiveness (MINECO) (Grant no. AGL2011-29831-C03-02 and AGL2014-55921-C2-2-P). Eddy W. Calle was supported by a research grant within the Babel project from the Erasmus Mundus programme.Calle, EW.; García, ML.; Blasco, A.; Argente, M. (2017). Correlated response in early embryonic development in rabbits selected for litter size variability. World Rabbit Science. 25(4):323-327. https://doi.org/10.4995/wrs.2017.6340SWORD32332725

Degradation of Organics in a Glow Discharge Under Martian Conditions

The primary objective of this project is to understand the consequences of glow electrical discharges on the chemistry and biology of Mars. The possibility was raised some time ago that the absence of organic material and carbonaceous matter in the Martian soil samples studied by the VikinG Landers might be due in part to an intrinsic atmospheric mechanism such as glow discharge. The high probability for dust interactions during Martian dust storms and dust devils, combined with the cold, dry climate of Mars most likely results in airborne dust that is highly charged. Such high electrostatic potentials generated during dust storms on Earth are not permitted in the low-pressure CO2 environment on Mars; therefore electrostatic energy released in the form of glow discharges is a highly likely phenomenon. Since glow discharge methods are used for cleaning and sterilizing surfaces throughout industry, the idea that dust in the Martian atmosphere undergoes a cleaning action many times over geologic time scales appears to be a plausible one

Correlated response in litter size components in rabbits selected for litter size variability

[EN] A divergent selection experiment for the environmental variability of litter size (Ve) over seven generations was carried out in rabbits at the University Miguel Hernandez of Elche. The Ve was estimated as the phenotypic variance within the female, after correcting for year-season and parity-lactation status. The aim of this study was to analyse the correlated responses to selection in litter size components. The ovulation rate (OR) and number of implanted embryos (IE) in females were measured by laparoscopy at 12 day of the second gestation. At the end of the second gestation, the total number of kits born was measured (TB). Embryonic (ES), foetal (FS) and prenatal (PS) survival were computed as IE/OR, TB/IE and TB/OR, respectively. A total of 405 laparoscopies were performed. Data were analysed using Bayesian methodology. The correlated response to selection for litter size environmental variability in terms of the litter size components was estimated as either genetic trends, estimated by computing the average estimated breeding values for each generation and each line, or the phenotypic differences between lines. The OR was similar in both lines. However, after seven generations of selection, the homogenous line showed more IE (1.09 embryos for genetic means and 1.23 embryos for phenotypic means) and higher ES than the heterogeneous one (0.07 for genetic means and 0.08 for phenotypic means). The probability of the phenotypic differences between lines being higher than zero (p) was 1.00 and .99, respectively. A higher uterine overcrowding of embryos in the homogeneous line did not penalize FS; as a result, this line continued to show a greater TB (1.01 kits for genetic means and 1.30 kits for phenotypic means, p=.99, in the seventh generation). In conclusion, a decrease in litter size variability showed a favourable effect on ES and led to a higher litter size at birth.Spanish Ministry of Economy and Competitiveness (MINECO), Grant/Award Number: AGL2011-29831-C03-02, AGL2014-55921-C2-2-P; Babel project from the Erasmus Mundus programmeArgente, MJ.; Calle, EW.; Garcia, ML.; Blasco Mateu, A. (2017). Correlated response in litter size components in rabbits selected for litter size variability. Journal of Animal Breeding and Genetics. 134(6):505-511. https://doi.org/10.1111/jbg.12283S505511134

Contextualización de la Agricultura y el Patrimonio a miras de Identificar y Caracterizar Productos de Interés Patrimonial/Contextualization of Agriculture and Heritage in order to Identify and Characterize Products of Patrimonial Interest

El Gobierno Provincial de Chimborazo contó con un proceso enriquecedor y participativo de alrededor de tres años que devino en la construcción de una Agenda De Competitividad, la misma que marca una línea de proyección para el fomento productivo de la Provincia de Chimborazo. Dentro de una lectura de estrategias agrícolas, se precisaron un conjunto de productos con una profunda relación social, pero que presentan serias debilidades en términos de productividad y posibilidades de mercado, como por ejemplo diversas variedades tubérculos andinos, o ciertas gramíneas, empero no por ello hay que extralimitar estos cultivos frente al desarrollo, al contrario, en función de la sostenibilidad son una prioridad de rescatar, mantener y valorizar. El objetivo de este trabajo es realizar una contextualización y conceptualización de manera preliminar con la finalidad de identificar y caracterizar los productos agrícolas de importancia patrimonial para la provincia de Chimborazo. Como parte del proceso de la Agenda de Competitividad de la Provincia de Chimborazo surgió la necesidad de establecer una investigación que amplié información de base para generar sustentos y criterios que permitan establecer estrategias apropiadas y oportunas, teniendo corresponsabilidad con el esfuerzo de la colectividad chimboracense, especialmente del sector rural, en la apropiación de sus condiciones y la búsqueda de la identidad productiva para la provincia. The Government of Province of Chimborazo had an enriching and participatory process of about three years that resulted in the construction of a Competitiveness Agenda to mark a line of projection for productive development. Within a reading of agricultural strategies, a set of products with a deep social relationship was required, but which present serious weaknesses in terms of productivity and market possibilities, for example, such as diverse varieties of Andean tubers, or certain gramineous, but not for this, we must overreach these crops against development, instead, depending on sustainability they are a priority to rescue, maintain and value. The objective of this work is to make a contextualization and conceptualization in a preliminary way in order to identify and characterize agricultural products of heritage importance for the province of Chimborazo. As part of process from Competitiveness Agenda of Province of Chimborazo, the need arose to establish an investigation that broadened base information to generate support and criteria for establishing appropriate and timely strategies, co-responsibility with the effort of the Chimboracense community, especially the rural sector, in the appropriation of their conditions and the search for productive identity for the province. Palabras clave: Gestión social, Sostenibilidad, Línea de tiempo, Salvaguardia, Sistematización. Keywords: Social management, Sustainability, Timeline, Safeguard, Systematization

Paper Session I-C - Comparison of Surface Resistivity and Triboelectric Charge Generation Characteristics of Materials

Electrostatic discharge can be a significant threat to electronic components, equipment and personnel, especially when working around flammable materials. The development of ways to predict the susceptibility of materials to generate significant charge is important for the safety of these personnel and equipment. The classification of materials as conductors or insulators is based on the surface resistivity of the materials. Though surface resistivity is an important piece of information when choosing electrostatically safe materials, this classification system does not provide any information as to the probability of the materials to generate charge when placed in contact with other materials (triboelectric charging). Without that information, the probability for hazardous electrostatic discharge to occur is not known. In this paper we show that there is no significant correlation between surface resistivity and triboelectric charge generation and emphasize the need for a test method to predict the susceptibility of materials for triboelectric charge generation in order to better evaluate a material’s propensity to cause an electrostatic discharge

Paper Session II-B - Performance Status of the Mars Environmental Compatibility Assessment Electrometer

The Mars Environmental Compatibility Assessment electrometer is an instrument intended to fly on a future Mars lander mission. The electrometer was designed primarily to investigate (1) the electrostatic interaction between the Martian soil and five different types of insulators attached to the electrometer, which are to be rubbed over the Martian soil. The MECA Electrometer is also capable of measuring (2) the presence of charged particles in the Martian atmosphere, (3) the local electric field strength, and (4) the local temperature. We have tested and evaluated the measurement capabilities of the MECA Electrometer under simulated Martian surface conditions using facilities located in the Electromagnetic Physics Testbed at KSC. The results of the study have demonstrated that rubbing an insulator over the Martian soil simulant does triboelectrically charge up the insulator\u27s surface. However, the charge buildup on an insulator was found to be as low as 1% of the current maximum range of the electrometer when it is rubbed through Martian soil. This indicates that the overall gain of the MECA Electrometer could be increased by a factor of 50, if measurements at the 50% level of full-range sensitivity are desired. The ion gauge, which detects the presence of charged particles, was also evaluated over the pressure range 13 - 533 mbar, and results will be presented

Monitoring Active Sites for Hydrogen Evolution Reaction at Model Carbon Surfaces

Carbon is ubiquitous as an electrode material in electrochemical energy conversion devices. If used as support material, the evolution of H2 is undesired on carbon. However, recently carbon-based materials are of high interest as economic and eco-conscious alternative to noble metal catalysts. The targeted design of improved carbon electrode materials requires atomic scale insight into the structure of the sites that catalyse H2 evolution. This work demonstrates that electrochemical scanning tunnelling microscopy under reaction conditions (n-EC-STM) can monitor active sites of highly oriented pyrolytic graphite for the hydrogen evolution reaction. With down to atomic resolution, the most active sites in acidic medium are pinpointed near edge sites and defects, whereas the basal planes remain inactive. Density functional theory calculations support these findings and reveal that only specific defects on graphite are active. Motivated by these results, the extensive usage of n-EC-STM on doped carbon-based materials is encouraged to locate their active sites and guide the synthesis of enhanced electrocatalysts.The authors thank Prof. Plamen Atanassov (University of California, Irvine, USA) and Dr. Jun Maruyama (Osaka Research Institute of Industrial Science and Technology, Japan) for fruitful discussion regarding some experimental results. RMK, RWH and ASB acknowledge the financial support from the German Research Foundation (DFG), in the framework of the projects BA 5795/4-1 and BA 5795/3-1, and under Germany's Excellence Strategy–EXC 2089/1–390776260, cluster of excellence ‘e-conversion’. ASB acknowledges the funding from the European Union's Horizon 2020 research and innovation programme under grant agreement HERMES No. 952184. FCV acknowledges financial support from Spanish MICIUN through RTI2018-095460-B-I00 and María de Maeztu (MDM-2017-0767) grants and a Ramón y Cajal research contract (RYC-2015-18996), and also from Generalitat de Catalunya (grants 2017SGR13 and XRQTC). The use of supercomputing facilities at SURFsara was sponsored by NWO Physical Sciences, with financial support from NWO

Paper Session I-A - Electrostatic Charging of Polymers by Particle Impact at Martian Atmospheric Pressurs

Studies of the electrostatic interaction between micrometer-sized particles and polymer surfaces are of great interest to NASA’s planetary exploration program. The unmanned landing missions to Mars planned for this decade as well as the possible manned missions that might take place during the second decade of this century require a better understanding of the electrostatic response of the materials used in landing crafts and equipment when exposed to wind-blown dust or to surface dust and sand particles. We report on preliminary experiments designed to measure the electrostatic charge developed on three polymer surfaces as they are impacted by Mars simulant particles less than 5 micrometers in diameter moving at 20 m/s. Experiments were performed in a CO2 atmosphere at 10 mbars of pressure using a particle delivery method that propels the particles without contact. The polymer surfaces, commonly used in space applications, were chosen so that they span the triboelectric series

Causality bounds for neutron-proton scattering

We consider the constraints of causality and unitarity for the low-energy interactions of protons and neutrons. We derive a general theorem that non-vanishing partial-wave mixing cannot be reproduced with zero-range interactions without violating causality or unitarity. We define and calculate interaction length scales which we call the causal range and the Cauchy-Schwarz range for all spin channels up to J = 3. For some channels we find that these length scales are as large as 5 fm. We investigate the origin of these large lengths and discuss their significance for the choice of momentum cutoff scales in effective field theory and universality in many-body Fermi systems.Comment: 36 pages, 10 figures, 7 tables, version to appear in Eur. Phys. J.

The Prediction of Long-Term Coating Performance from Short-Term Electrochemical Data

The pace of coatings development is limited by the time required to assess their corrosion protection properties. This study takes a step f orward from Part I in that it correlates the corrosion performance of organic coatings assessed by a series of short-term electrochemical measurement with 18-month beachside exposure results of duplicate pan els. A series of 19 coating systems on A36 steel substrates were test ed in a completely blind study using the damage tolerance test (DTT). In the DTT, a through-film pinhole defect is created, and the electro chemical characteristics of the defect are then monitored over the ne xt 4 to 7 days while immersed in 0.SM NaCl. The open circuit potentia l, anodic potentiostatic polarization tests and electrochemical imped ance spectroscopy were used to study the corrosion behavior of the co ating systems. The beachside exposure tests were conducted at the Ken nedy Space Center according to ASTM D610-01. It was found that for 79 % of the coatings systems examined, the 18 month beachside exposure r esults could be predicted by two independent laboratory tests obtained within 7 days