The Effect of Traditional Practices in the Efficiency of Dairy Farms in Wisconsin

The US dairy sector is facing structural changes including a geographical shift in dairy production and a tendency towards the implementation of more intensive production systems. These changes might significantly affect farm efficiency, profitability and the long-term economic sustainability of the dairy sector, especially in more traditional dairy production areas. Consequently, the goal of this study was to examine the impact of practices commonly used by dairy farmers and the effect of intensification on the performance of the farms. We used a sample of 273 Wisconsin dairy farms to estimate a stochastic production frontier simultaneously with a technical inefficiency model. The empirical analysis showed that at a commercial level the administration of bovine somatotropin hormone to lactating cows increases milk production. In addition, we found that production exhibits constant returns to scale and that farm efficiency is positively related to farm intensification, the level of contribution of family labor in the farm activities, the use of a total mixed ration (TMR) feeding system and the milking frequency.Technical inefficiency, stochastic production frontier, intensification, Livestock Production/Industries, Productivity Analysis,

Friendly index sets of starlike graphs

For a graph G = (V, E) and a coloring (labeling) f : V(G) → Z2 let vf(i) = | f-1(i)|. The coloring f is said to be friendly if |vf(1) - v f(0)| ≤ 1. The coloring f : V( G) → Z2 induces an edge labeling f* : E( G) → Z2 defined by f* (xy) = f( x) + f(y) (mod 2). Let ef(i) = |f*-1( i)|. The friendly index set of the graph G, denoted by FI (G), is defined by FIG= ef1-ef 0:f isafriendly vertexlabelingof G. In this thesis the friendly index sets of certain classes of trees, called starlike graphs, will be determined

ReAFFIRM: Real-time Assessment of Flash Flood Impacts: a Regional high-resolution Method

Flash floods evolve rapidly in time, which poses particular challenges to emergency managers. One way to support decision-making is to complement models that estimate the flash flood hazard (e.g. discharge or return period) with tools that directly translate the hazard into the expected socio-economic impacts. This paper presents a method named ReAFFIRM that uses gridded rainfall estimates to assess in real time the flash flood hazard and translate it into the corresponding impacts. In contrast to other studies that mainly focus on in- dividual river catchments, the approach allows for monitoring entire regions at high resolution. The method consists of the following three components: (i) an already existing hazard module that processes the rainfall into values of exceeded return period in the drainage network, (ii) a flood map module that employs the flood maps created within the EU Floods Directive to convert the return periods into the expected flooded areas and flood depths, and (iii) an impact assessment module that combines the flood depths with several layers of socio- economic exposure and vulnerability. Impacts are estimated in three quantitative categories: population in the flooded area, economic losses, and affected critical infrastructures. The performance of ReAFFIRM is shown by applying it in the region of Catalonia (NE Spain) for three significant flash flood events. The results show that the method is capable of identifying areas where the flash floods caused the highest impacts, while some locations affected by less significant impacts were missed. In the locations where the flood extent corresponded to flood observations, the assessments of the population in the flooded area and affected critical infrastructures seemed to perform reasonably well, whereas the economic losses were systematically overestimated. The effects of different sources of uncertainty have been discussed: from the estimation of the hazard to its translation into impacts, which highly depends on the quality of the employed datasets, and in particular on the quality of the rainfall inputs and the comprehensiveness of the flood maps.Peer ReviewedPostprint (published version

Breaking of isospectrality of quasinormal modes in nonrotating loop quantum gravity black holes

We acknowledge D. Brizuela, R. Gambini, J. L. Jaramillo, J. Martos, J. Pullin, and C. Sopuerta for very useful comments. This work is supported by the Spanish Government through the Projects No. PID2020– 118159 GB-C43, No. PID2019–105943 GB-I00 (with FEDER contribution), and the “Operative Program FEDER2014-2020 Junta de Andalucía-Consejería de Economía y Conocimiento” under Project No. E-FQM- 262-UGR18 by Universidad de Granada. Daniel del-Corral is grateful for the support of Grant No. UI/BD/151491/ 2021 from the Portuguese Agency Fundao para a Cincia e a Tecnologia. This research was funded by Fundao para a Cincia e a Tecnologia Grant No. UIDB/MAT/00212/2020.We study the quasinormal frequencies of three effective geometries of nonrotating regular black holes derived from loop quantum gravity. Concretely, we consider the Ashtekar-Olmedo-Singh and two Gambini- Olmedo-Pullin prescriptions. We compute the quasinormal frequencies of axial and polar perturbations adopting a WKB method. We show that they differ from those of classical general relativity and, more importantly, that isospectrality is broken. Nevertheless, these deviations are tiny, even for microscopic black holes, and they decay following an inverse power law of the size of the mass of the black holes. For the sake of completeness, we also analyze scalar and vector perturbations, reaching similar conclusions.Spanish Government PID2020– 118159 GB-C43 PID2019–105943 GB-I00Operative Program FEDER2014-2020 Junta de Andalucía-Consejería de Economía y Conocimiento E-FQM- 262-UGR18 Universidad de GranadaUI/BD/151491/ 2021 Portuguese Agency Fundao para a Cincia e a TecnologiaFundao para a Cincia e a Tecnologia Grant No. UIDB/MAT/00212/202

A Dual Model of Relational Concept Representation

Relational concepts pervade daily life, as people are regularly required to comprehend, articulate, and reason about relational ideas and scenarios. Critically, these processes might be altered by how such concepts are represented. The dominant theories of relational learning have been built on the assumption that relational concepts are represented compositionally, based on the relationships among a concept’s components. However, these theories have typically neglected the possibility that a concept’s components can be consolidated or chunked into a unitized concept, producing a representation that is devoid of the concept’s component parts. The distinction between compositional and unitary representations of relational concepts is a natural consequence of structure-mapping theory, but its psychological implications have not been explored. This paper reports 7 studies that examine how people represent relational concepts and how such representations affect relational learning. The general take away from these studies is that people do indeed appear to be capable of representing relational concepts in two fundamentally different ways, unitarily and compositionally. Furthermore, unitary representations seem to lead to better relational learning than compositional representations, especially for inference-based tasks. However, the data suggest that there might be various factors that interact with how representation affects relational learning (e.g., individual differences in representation, type of task, type of comparison). The conclusion that follows from these studies is that unitary representations might incur less cognitive load than structural alignment of compositional representations, and thus may be the default for everyday relational reasoning