Generalized Hyperbolicity and Shadowing in LpL^p spaces

It is rather well-known that hyperbolic operators have the shadowing property. In the setting of finite dimensional Banach spaces, having the shadowing property is equivalent to being hyperbolic. In 2018, Bernardes et al. constructed an operator with the shadowing property which is not hyperbolic, settling an open question. In the process, they introduced a class of operators which has come to be known as generalized hyperbolic operators. This class of operators seems to be an important bridge between hyperbolicity and the shadowing property. In this article, we show that for a large natural class of operators on $L^p(X)$ the notion of generalized hyperbolicity and the shadowing property coincide. We do this by giving sufficient and necessary conditions for a certain class of operators to have the shadowing property. We also introduce computational tools which allow construction of operators with and without the shadowing property. Utilizing these tools, we show how some natural probability distributions, such as the Laplace distribution and the Cauchy distribution, lead to operators with and without the shadowing property on $L^p(X)$

Shift-like Operators on Lp(X)L^p(X)

In this article we develop a general technique which takes a known characterization of a property for weighted backward shifts and lifts it up to a characterization of that property for a large class of operators on $L^p(X)$. We call these operators ``shift-like''. The properties of interest include chaotic properties such as Li-Yorke chaos, hypercyclicity, frequent hypercyclicity as well as properties related to hyperbolic dynamics such as shadowing, expansivity and generalized hyperbolicity. Shift-like operators appear naturally as composition operators on $L^p(X)$ when the underlying space is a dissipative measure system. In the process of proving the main theorem, we provide some results concerning when a property is shared by a linear dynamical system and its factors.Comment: arXiv admin note: text overlap with arXiv:2009.1152

Linear Dynamics Induced by Odometers

Weighted shifts are an important concrete class of operators in linear dynamics. In particular, they are an essential tool in distinguishing variety dynamical properties. Recently, a systematic study of dynamical properties of composition operators on $L^p$ spaces has been initiated. This class of operators includes weighted shifts and also allows flexibility in construction of other concrete examples. In this article, we study one such concrete class of operators, namely composition operators induced by measures on odometers. In particular, we study measures on odometers which induce mixing and transitive linear operators on $L^p$ spaces.Comment: 15 pages, keywords: linear dynamics, composition operators, topological mixing, topological transitivity, odometer

Ovariectomy impairs socio-cognitive functions in dogs

Recent studies have underlined the effect of ovariectomy on the spatial cognition of female dogs, with ovariectomized dogs showing a clear preference for an egocentric rather than an allocentric navigation strategy whereas intact females did not show preferences. Intact females had better performances than gonadectomized females in solving a learning task in a maze. Ovariectomy also affects socio-cognitive abilities, reducing the dog's level of attention on the owner. We tested dogs (Canis lupus familiaris) in the object choice task paradigm to assess whether an ovariectomy could impair females' ability to follow human signals. Forty pet dogs (18 intact females (IF) and 22 gonadectomized females (GF)) were tested in the object choice task paradigm using the human proximal pointing gesture. For the analysis, the frequency of correct, wrong and no-choices was collected; moreover, the latency of the correct choices was also considered. The IF group followed the pointing gestures more often than the GF group and with a lower latency, whereas a significantly higher no-choice frequency was recorded for the GF group. These results show a detrimental effect of ovariectomy on dogs' socio-cognitive skills related to the responsiveness to human pointing gestures

The scent of emotions: A systematic review of human intra- and interspecific chemical communication of emotions.

The sense of olfaction has been considered of minor importance in human communication. In recent years, evidence has emerged that humans might be influenced by unconscious messages sent through chemosignals in body odors. Data concerning the ability of humans to recognize fear, maybe related to the evolutionary role of these emotions in the fight-or-flight reactions, are well known. To further understand the role of emotional chemosignals in mediating communication in humans and its influence on animal behaviors, we conducted a systematic literature review. Chemosignals derived from axillary odors collected under a variety of emotional stimuli and sad tears in humans affect receivers' social interactions, danger detection and risk-taking behavior, social aspects of eating, and performance under stressing conditions. In addition, beyond the fight-or-flight response, even the body odors of happiness can be perceived by others. Furthermore, human chemosignals can influence behaviors and stressful responses in animals, particularly dogs and horses, which may partially explain their special relationship with humans. Our review highlights the importance of chemosignaling in human intra- and interspecific interactions and suggests the need for further investigations, both in physiological conditions and in patients with psychiatric or neurodegenerative disorders

Higher forage:concentrate ratio and space availability may favor positive behaviors in dairy cows

A novel livestock management system (LMS) for dairy cows mainly based on a high forage:concentrate ratio, no silage, and large outdoor paddocks, has been introduced in Italy during the last five years. It was proved that such system, further than improving the quality of milk, benefits the health status of cows. The goal of the present research was to compare the behavioral responses of a group of animals kept with the LMS and outdoor paddocks of 200 m2, and cows reared in a traditional semi-intensive manner and outdoor paddocks of 100 m2. The study was carried out on Italian Friesian cows analyzing the feeding and social behaviors and the locomotor activity. The statistical analysis of locomotor activity showed that the HFC group spent lower time lying down and standing and higher time walking; they also showed a longer rumination time and spent less time drinking. Furthermore, the HFC group displayed longer allogrooming and social rubbing times. Results suggest that the novel LMS could be the basis for an improvement of the cows' welfare

Effects of Sorghum silage in lactating buffalo cow diet: Biochemical profile, milk yield, and quality

The influence of replacing silage with sorghum silage in the diet of dairy buffalo cows on metabolic status and on milk yield, chemical characteristics, and fatty acid profile was studied. Forty dairy buffalo cows were included in the trial and divided into two homogeneous groups (SS, sorghum silage and CS, corn silage). Blood was collected at the end of the trial (120 days), individual milk yield was registered daily. Samples of milk were monthly collected and analyzed for fat, protein, and lactose. Moreover, fatty acid profiles of silages and milk were determined. Buffalo cows fed sorghum silage showed an average milk yield higher than group CS (kg/d 10.120 vs. 9.270; p < 0.05), probably due to the lower lignin content of sorghum silage (31.0 g/kg dry matter (DM)) compared to corn silage (47.0 g/kg DM) and, by consequence, to the higher digestibility of SS diet. The percentage of linoleic acid was significantly higher in milk of group CS (C18:2: 1.27 vs. 2.05%; p < 0.01) due to the higher content of these acids in corn than in sorghum silage. The omega 6/omega 3 ratio was significantly lower in milk from buffalo cows fed sorghum than those fed corn silage (7.8 vs. 12.9; p < 0.01). Serum biochemistry showed no negative effects of the corn replacing with sorghum

Effects of Linseed Supplementation on Milk Production, Composition, Odd-and Branched-Chain Fatty Acids, and on Serum Biochemistry in Cilentana Grazing Goats

The purpose of this study was to investigate the effects of linseed supplementation on milk yield and quality, serum biochemistry and, in particular, to evaluate its possible effects on the production of odd-and branched-chain fatty acids (OBCFA) in the milk of Cilentana grazing goats. Twelve pregnant Cilentana dairy goats were divided into two groups (CTR, control, and LIN, linseed supplementation group). After kidding, the goats had free access to the pasture and both groups received a supplement of 400 g/head of concentrate, but the one administered to the LIN group was characterized by the addition of linseed (in a ratio of 20% as fed) to the ingredients. During the trial, milk samples were taken from April to August in order to evaluate milk production, composition, and fatty acid profile. In addition, blood samples were taken for evaluating the effects of linseed supplementation on goats’ health status. The health status of the goats was not influenced by the linseed supplementation, as confirmed by blood analyses. Concerning the effects on milk, the supplementation positively affected (p < 0.001) milk production and fat percentage and the fatty acid profile was markedly influenced by the lipid supplementation. In particular, milk from the LIN group was characterized by significantly lower concentrations of saturated fatty acids (FA; p < 0.001) and higher proportions of monounsaturated FA, polyunsaturated FA, and conjugated linoleic acids (CLAs) than milk from the CTR group (p < 0.001). In contrast, the OBCFA were negatively influenced by the linseed supplementation (p < 0.0001). Further studies are needed to test the effects of different fat sources and other nutrients on the diets

Effects of ecotrofin™ on milk yield, milk quality and serum biochemistry in lactating goats

A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400&nbsp;g/day of corn meal, and the treated group was supplemented with 20&nbsp;g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30&nbsp;days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega-6:omega-3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, p&nbsp;&lt;&nbsp;0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed

Dietary supplementation with a phytocomplex affects blood parameters and milk yield and quality in grazing goats

A phytocomplex composed by Schizochytrium limacinum, a species of marine alga, Galega officinalis, an herbaceous plant of the Faboideae subfamily, and linseeds, was administered to lactating grazing goats in order to evaluate its effects on milk yield and quality, and to investigate possible effects on goat health status. The hypothesis was that, by using a phytocomplex including plants known to exert an improvement of milk yield and milk quality, a synergism should be possible in order to obtain such effects using low doses, thus avoiding adverse effects. Milk fat was significantly (p&lt;0.05) higher in treated group (4.02 vs. 3.61 %), in particular, levels of MUFA (24.55 vs 22.56 %), total n3 (1.34 vs 1.19 %) and total CLAs (0.52 vs. 0.40 %), were increased while n6/n3 (1.71 vs. 2.21 %) ratio was decreased. Concerning biochemical parameters, a significant (p&lt;0.05) decrease of creatinine (0.73 vs. 0.84 mg/dl) was observed in treated animals, but the levels fell within the normal range for this species. Thus, the addition of the proposed phytocomplex to the diet of grazing goats may be successfully used to improve milk fatty acids profile without negative effects on animal health