Nonradial entire solutions for Liouville systems

We consider the following system of Liouville equations: $$\left\{\begin{array}{ll}-\Delta u_1=2e^{u_1}+\mu e^{u_2}&\text{in }\mathbb R^2\\-\Delta u_2=\mu e^{u_1}+2e^{u_2}&\text{in }\mathbb R^2\\\int_{\mathbb R^2}e^{u_1}<+\infty,\int_{\mathbb R^2}e^{u_2}<+\infty\end{array}\right.$$ We show existence of at least $n-\left[\frac{n}3\right]$ global branches of nonradial solutions bifurcating from $u_1(x)=u_2(x)=U(x)=\log\frac{64}{(2+\mu)\left(8+|x|^2\right)^2}$ at the values $\mu=-2\frac{n^2+n-2}{n^2+n+2}$ for any $n\in\mathbb N$.Comment: 18 pages, accepted on Journal of Differential Equation

Le strategie di trading basate sull’effetto momentum

Starting from the second half of the Seventies, several researches made in the financial markets doubt the existence of the efficient market hypothesis. In particular, large analyses on this item document evidence in the stock prices of patterns that allow us to obtain extra return. Among these “anomalies”, classified into various categories, basing on the different subject of the research, it is emphasized the existence of the short-term “momentum” effect (Jegadeesh and Titman, 1993), from which we can draw out the trading strategy suggesting us to buy the “winner” securities and to sell the “loser” ones. The basic idea of this strategy is that stock performances persist in the short-term, so the winners will go on winning and vice versa. The portfolios that in the previous period have achieved high performances will persist after their formation period and will overperform portfolios that in the previous periods have obtained lower results. Momentum trading strategies are particularly profitable not only in the USA, but also in European markets (Rouwenhorst, 1988); on the opposite, the effect is very weak in the Asian market, especially in the Japanese one (Chui, Titman and Wei, 2000). At the present time, researches carried out on this item are focused on the sources of the momentum profits. The argument is particularly argued because, being the traditional finance not able to explain the profits of the strategy, several researchers look to the behavioural models. These ones, even if sharing the same subject of the research (that is, everyone of them has the purpose to explain the way in which information are reflected in stock prices, causing a positive correlation in the short term), are however different because of the kind of psychological phenomenon at the origin of it. That is, if it is determined by an over or an underreaction to the event by the investors. So, researchers build different hypothesis about the heuristic mistakes that affect the investors’ behaviour (Daniel, Hirshleifer and Subrahmanyam, 1998; Barberis, Shleifer and Vishny, 1998; Hong and Stein, 1999)

Mouse model of panic disorder: Vulnerability to early environmental instability is strain-dependent.

AbstractEarly life experiences and genetic background shape phenotypic variation. Several mouse models based on early treatments have evaluated short‐ and long‐term phenotypic alterations and explored their molecular mechanisms. The instability of maternal cues was used to model human separation anxiety in outbred mice, one of the etiopathogenetic factors that predict panic disorder (PD). Application of the repeated cross‐fostering (RCF) protocol to inbred strains (C57 and DBA) allowed us to measure differential responses to the same experimental manipulation. Ultrasounds emitted during isolation indicated that after RCF, pups from both strains lose their ability to be comforted by nest cues, but the frequency modulation of separation calls increased in RCF‐C57 and decreased in RCF‐DBA mice. No strain‐specific difference in olfactory ability explained these responses in RCF‐exposed mice. Rather, disruption of the infant‐mother bond may differentially affect separation calls in the two strains. Moreover, the RCF‐associated increased respiratory response to hypercapnia–an endophenotype of human PD documented among mice outbred strains–was replicated in the C57 strain only. We suggest that RCF‐induced instability of the early environment affects emotionality and respiratory physiology differentially, depending on pups' genetic background. These strain‐specific responses provide a lead to understand differential vulnerability to emotional disorders

Reliability and Heterogeneity of Real Estate Indexes and their Impact on the Predictability of Returns.

This paper addresses the issue of data quality in the real estate market. In many countries, the returns indices for direct markets are provided by several sources differing in terms of the methodology adopted and index weights. These differences produce a lack of informative standardization, which could negatively affect the ability of market participants to make predictions. By focusing on the Italian real estate market, the aim of the paper is therefore twofold: to investigate the reliability of property data sources, and to assess the impact for financial intermediaries involved in real estate investments. Our results show a significant level of divergence between the data, and considerable implications for those financial institutions dealing with them. These findings conflict with the requirements of an efficient (or at least sub-efficient) market

Emotional impact in β-thalassaemia major children following cognitive-behavioural family therapy and quality of life of caregiving mothers

Cognitive-Behavioural Family Therapy (CBFT) can be an effective psychological approach for children with beta-thalassaemia major, increasing compliance to treatment, lessening the emotional burden of disease, and improving the quality of life of caregivers

Tribological Behaviour of Ceramic Hip Replacements

Since 1960, when the first hip prosthesis was introduced, up to now, several implant typologies have been proposed trying to meet the increasing clinical demands of more and more active and young patients. A substantial evolution of implant design has been occurring, both in terms of materials and geometry, basically driven by their tribological performances. Indeed, the main concern of hip implants consists in the release of wear debris, which can lead to implant loosening and failure. Thus, many studies on wear and lubrication of hip prostheses have been published in the last 15 years, mainly focused on experimental researches but also on numerical/modeling approaches. The aim of this work is to review the history of hip implants from a tribological point of view with a focus on ceramic-on-ceramic replacements, which represent the most advanced solution in terms of wear strength and chemical inertness. The main drawbacks of these implants, as the brittleness and the squeaking, are discussed and novel solutions examined

Permissive role for mGlu1 metabotropic glutamate receptors in excitotoxic retinal degeneration

Neuroprotection is an unmet need in eye disorders characterized by retinal ganglion cell (RGC) death, such as prematurity-induced retinal degeneration, glaucoma, and age-related macular degeneration. In all these disorders excitotoxicity is a prominent component of neuronal damage, but clinical data discourage the development of NMDA receptor antagonists as neuroprotectants. Here, we show that activation of mGlu1 metabotropic glutamate receptors largely contributes to excitotoxic degeneration of RGCs. Mice at postnatal day 9 were challenged with a toxic dose of monosodium glutamate (MSG, 3g/kg), which caused the death of >70% of Brn-3a+ RGCs. Systemic administration of the mGlu1 receptor negative allosteric modulator (NAM), JNJ16259685 (2.5mg/kg, s.c.), was largely protective against MSG-induced RGC death. This treatment did not cause changes in motor behavior in the pups. We also injected MSG to crv4 mice, which lack mGlu1 receptors because of a recessive mutation of the gene encoding the mGlu1 receptor. MSG did not cause retinal degeneration in crv4 mice, whereas it retained its toxic activity in their wild-type littermates. These findings demonstrate that mGlu1 receptors play a key role in excitotoxic degeneration of RGCs, and encourage the study of mGlu1 receptor NAMs in models of retinal neurodegeneration