133,796 research outputs found
Technical Note: Year, season, and parity effect on weaning performance of the Carmagnola Grey Rabbit breed
No full textTo evaluate the main environmental factors in the productivity of Carmagnola Grey rabbits, an endangered breed indigenous to northern Italy, data collected over 8 years were analysed. Production data on the pure closed nucleus herd of the University of Turin were used. Effects of parity, season and age of weaning on the number of rabbits born alive and weaned, litter weight and individual average weight at weaning were studied. The following average performance rates over the 8 years period were determined: 8.1 live born and 7.2 weaned kits per litter and a litter weight at weaning of 7287 g or 1024 g individual weaning weight. Year and season both had a significant effect (P < 0.001) on all the traits studied as well as weaning age (P < 0.001).Lazzaroni, C.; Biagini, D.; Redaelli, V.; Luzi, F. (2012). Technical Note: Year, season, and parity effect on weaning performance of the Carmagnola Grey Rabbit breed. World Rabbit Science. 20(1):57-60. https://doi.org/10.4995/wrs.2012.1031SWORD576020
Quod raro alias, praetorianus urbanusque miles in aciem deducti. Some considerations on the participation of the praetorian and urban cohorts in the civil wars of 69 A.D.: critical evaluation of the literary sources and the expedition against Narbonne Gaul (Part I)
No full textDuring the year of the four emperors the Praetorian Guard and the Urban cohorts played an important role in the military events of the civil wars. the paper examines some problems related to the involvement of these military corps in the military campaigns of AD 69. the literary sources often describe the Praetorians and the Urbaniniciani as passionate and violent, like the other milites of the Roman army, and moreover as second-rate and undisciplined soldiers; a careful analysis assesses if these descriptions are truthful or depend on the use of literary topoi and if the soldiers of urban troops were really inferior warriors to the legionaries serving on the frontier. Secondly, the paper examines accurately one of the conflicts in which the urban troops took part: the maritime expedition that Otho launched to attack Narbonense Gaul. the analysis of the literary and epigraphic documentation, thanks to new updated interpretations of the sources, fosters the acquisition of new and more precise historical information in order to reconstruct this military campaign
Quod raro alias, praetorianus urbanusque miles in aciem deducti. Unsolved problems and new interpretations on the movements and the composition of the urban troops during the civil wars of AD 69 (Part II)
No full textDuring the Year of the four emperors the Praetorian Guard and the Urban cohorts played an important role in the military events of the civil wars. The paper examines some problems related to the involvement of these military corps in the military campaigns of AD 69: the number of soldiers and cohorts participating in the different war scenarios, the movements and the fate of Otho’s Praetorians compared with Vitellius’ newly formed Praetorian cohorts. Moreover, in light to new interpretations of the sources, it analyzes the history and the composition of the four Urban cohorts created by Vitellius: in particular, I discuss the thesis according to which Vitellius mixed in legionaries formerly serving on the Rhine frontier and the old Otho’s urbaniciani within these new Urban cohorts
Caratterizzazione di due calcestruzzi UHPFRC commerciali: valutazione di proprietà meccaniche e di durabilità
No full textThis note presents the results of a research aimed at assessing and comparing the properties of two commercial Ultra-High-Performance Fiber Reinforced Concretes (UHPRFC) made with the same amount of steel fibers (2.5% vol.). Besides the basic properties at hardened state, such as compressive strength and elastic modulus, durability-related parameters are measured, such as electrical resistivity, resistance to carbonation and chloride penetration, water absorption rate and water absorption. Microstructure is also studied by means of optical and electron microscopy. The results show that, although fibers may locally increase the presence of interfacial voids in the cement paste and decrease the electrical resistivity of UHPFRC, both products exhibited an overall excellent behavior if compared to ordinary concrete
Carbonation-Induced Corrosion of Reinforced Concrete: Preliminary Results on the Collegi Universitari in Urbino
No full textInfluence of steel fibers on durability properties of UHPFRC
No full textUltra-high-performance fiber-reinforced concrete (UHPFRC) is a high-strength cementitious material whose composition can be designed to achieve given properties in the fresh and hardened state. Thanks to the low water/binder ratio (around 0.2) and to the presence of mineral additions, it is characterized by a low porosity which is often taken as a guarantee of intrinsic - almost unlimited - durability. However, the number of researches on the long-term behavior of this type of material is relatively limited, in particular with respect to the corrosion behavior of steel and to the role of steel fibers on concrete durability. This note presents the results of a research aimed at studying the influence of fibers on durability properties. Besides tests for the characterization at fresh and hardened state, durability-related parameters such as electrical resistivity, resistance to chloride penetration, absorption rate and water absorption are investigated. The results show that higher amount of fibers increased the porosity of fibers-concrete interfacial zone and therefore large fibers content negatively influences the parameters related to durability. However, the investigated parameters indicate higher performances with respect to ordinary concretes even in UHPFRC with large fiber content, except for electrical resistivity
A priori estimates and large population limits for some nonsymmetric Nash systems with semimonotonicity
No full textWe address the problem of regularity of solutions (Formula presented.) to a family of semilinear parabolic systems of (Formula presented.) equations, which describe closed-loop equilibria of some (Formula presented.) -player differential games with Lagrangian having quadratic behaviour in the velocity variable, running costs (Formula presented.) and final costs (Formula presented.). By global (semi)monotonicity assumptions on the data (Formula presented.) and (Formula presented.), and assuming that derivatives of (Formula presented.) in directions (Formula presented.) are of order (Formula presented.) for (Formula presented.), we prove that derivatives of (Formula presented.) enjoy the same property. The estimates are uniform in the number of players (Formula presented.). Such a behaviour of the derivatives of (Formula presented.) arise in the theory of Mean Field Games, though here we do not make any symmetry assumption on the data. Then, by the estimates obtained we address the convergence problem (Formula presented.) in a ‘heterogeneous’ Mean Field framework, where players all observe the empirical measure of the whole population, but may react differently from one another. We also discuss some results on the joint (Formula presented.) and vanishing viscosity limit
Corrosion of reinforcement in UHPFRC ::a preliminary study including the effect of cracking
No full textUltra-High Performance Fibre-Reinforced Concrete (UHPFRC) is characterized by high compressive strength, strain-hardening behaviour in tension and very low porosity. After cracking, crack opening is controlled by the fibres. Therefore, UHPFRC is generally considered as a very durable material and is frequently used in combination with reinforcement for elements exposed to severe environmental conditions. However, scientific evidence on the long-term behaviour of reinforcement embedded in UHPFRC is limited, especially if the simultaneous presence of cracks and chemical attack is considered. This contribution presents the results of a preliminary study carried out to characterize the corrosion behaviour of reinforcement in UHPFRC. Mechanical and durability-related properties of a commercial UHPFRC were determined. Accelerated and long-term corrosion tests were initiated on cracked and uncracked prisms reinforced with carbon or stainless steel rebars.Il calcestruzzo fibrorinforzato ad altissime presta-zioni (UHPFRC) è caratterizzato da un’elevata resistenza a compressione, un comportamento a trazione incrudente e una bassa po-rosità. Inoltre, la presenza di fibre limita l’apertura delle fessure in post-fessurazione. Per queste ragioni, il calcestruzzo UHPFRC è generalmente considerato un materiale durevole ed è spesso impiegato in combinazione con armature di rinforzo per la realizzazione di elementi esposti a condizioni ambientali aggressive. Tuttavia, in letteratura sono relativamente limitati gli studi sul comportamen-to alla corrosione delle armature in UHPFRC, in particolare considerando la contemporanea presenza di fessure e agenti aggressivi come i cloruri. La memoria presenta uno studio preliminare atto alla caratterizzazione del comportamento alla corrosione delle ar-mature in UHPFRC. Si determinano le proprietà meccaniche e alcuni parametri correlati alla durabilità di un UHPFRC commercia-le, insieme allo studio del comportamento alla corrosione di armature in provini armati con acciaio al carbonio o con acciaio inossi-dabile, anche in seguito a fessurazione del calcestruzzo
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