Non-equilibrium Phase Transitions: Activated Random Walks at Criticality

In this paper we present rigorous results on the critical behavior of the Activated Random Walk model. We conjecture that on a general class of graphs, including Z d , and under general initial conditions, the system at the critical point does not reach an absorbing state. We prove this for the case where the sleep rate λ is infinite. Moreover, for the one-dimensional asymmetric system, we identify the scaling limit of the flow through the origin at criticality. The case λ < +∞ remains largely open, with the exception of the one-dimensional totally-asymmetric case, for which it is known that there is no fixation at criticality.Fil: Cabezas, M.. Conselho Nacional de Desenvolvimiento Cientf y Tec. Associacao Instituto Nacional de Matemática Pura E Aplicada; BrasilFil: Trivellato Rolla, Leonardo. Conselho Nacional de Desenvolvimiento Cientf y Tec. Associacao Instituto Nacional de Matemática Pura E Aplicada; Brasil. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sidoravicius, V.. Conselho Nacional de Desenvolvimiento Cientf y Tec. Associacao Instituto Nacional de Matemática Pura E Aplicada; Brasi

Increasing Downlink Cellular Throughput with Limited Network MIMO Coordination

Single-user, multiuser, and network MIMO performance is evaluated for downlink cellular networks with 12 antennas per site, sectorization, universal frequency reuse, scheduled packet-data, and a dense population of stationary users. Compared to a single-user MIMO baseline system with 3 sectors per site, network MIMO coordination is found to increase throughput by a factor of 1.8 with intra-site coordination among antennas belonging to the same cell site. Intra-site coordination performs almost as well as a highly sectorized system with 12 sectors per site. Increasing the coordination cluster size from 1 to 7 sites increases the throughput gain factor to 2.5

Stochastic perturbations of convex billiards

We consider a strictly convex billiard table with C 2 boundary, with the dynamics subjected to random perturbations. Each time the billiard ball hits the boundary its reflection angle has a random perturbation. The perturbation distribution corresponds to the physical situation where either the scale of the surface irregularities is smaller than but comparable to the diameter of the reflected object, or the billiard ball is not perfectly rigid. We prove that for a large class of such perturbations the resulting Markov chain is uniformly ergodic, although this is not true in general.Fil: Markarian, R.. Universidad de la Republica. Facultad de Ingeniería; UruguayFil: Trivellato Rolla, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santalo". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santalo"; ArgentinaFil: Sidoravicius, V.. Jardim Botânico; BrasilFil: Tal, F. A.. Universidade de Sao Paulo; BrasilFil: Vares, M. E.. Universidade Federal do Rio de Janeiro; Brasi

Analisi territoriale delle percezioni dei possibili impatti dell'estrazione di idrocarburi sui prodotti con Indicazione Geografica

La Commissione Europea da sempre riconosce il grande valore dei prodotti alimentari tipici e tradizionali, importanti per la definizio- ne del patrimonio culturale e dell\u2019identit\ue0 di un territorio. Il sistema europeo delle Indicazioni Geografiche (IG) conferisce inoltre a questi prodotti il valore di propriet\ue0 intellettuali. Nonostante l\u2019Italia sia il Paese europeo pi\uf9 ricco di prodotti IG, nelle aree di produzione sono presenti attivit\ue0 antropiche potenzialmente impattanti per l\u2019am- biente, la sicurezza alimentare e la salute. In questa ricerca vengono presentati i risultati di un\u2019indagine, condotta in Basilicata e Veneto, sull\u2019eventuale cambio delle scelte di acquisto di prodotti IG in aree in cui vi sono attivit\ue0 di estrazione o lavorazione di idrocarburi. Le analisi GIS realizzate hanno permesso, inoltre, di mettere in relazione alcune aree di produzione di prodotti IG con la dimensione spaziale delle percezioni sul rischio per la sicurezza alimentare rilevate duran- te l\u2019indagine. I risultati della ricerca evidenziano la necessit\ue0 di poli- tiche e normative, a livello nazionale ed europeo, che definiscano per le attivit\ue0 pi\uf9 impattanti adeguate distanze di sicurezza dalle aree di produzione, tenendo conto anche delle percezioni dei consumatori

Lower urinary tract symptoms and mental health during COVID-19 pandemic

Objective: Coronaviruses (CoVs) are a group of RNA viruses involved in several human diseases affecting respiratory, enteric, hepatic, and neurological systems. COVID-19 was identified in 2020 and was named SARS-CoV-2. To limit worldwide contagion, many countries instituted a lockdown, which conducted to disruption of routine life. In fact, pandemic was associated with several stresses among population, such as loss of employment, deaths of family members, friends, or colleagues, financial insecurity, and isolation. This led to long-lasting psychosocial effects as anxiety and depression, increasing the prevalence of stress and traumarelated disorders in the population. The aim of this study was to investigate the correlation between lower urinary tracts symptoms (LUTS) and stress/depressive symptoms during COVID-19 pandemic. Materials and methods: An anonymous cross-sectional webbased survey (comprehending anthropometric data, education level, occupation status, smoking and alcohol habits, current therapies, quarantine and COVID-19 infection status) was conducted from March to May 2020 in Italy. LUTS were examined through National Institute of Health-Chronic Prostatitis Symptom Index (NIH-CPSI) and Genitourinary Pain Index (GUPI). Hamilton Depression Rating Scale (HDRS) was utilized to evaluate depressive and anxiety symptoms. Non-parametric Kruskal-Wallis H Test was used for statistical analysis. Results: A total of 356 out of 461 subjects fully completed the survey, with a response rate of 77.2%. Data showed that subjects involved in economic difficulties, quarantine measures or with increased HDRS reported a significative statistic worsened urinary symptoms (H(3) = 11.731, p = 0.008), quality of life, (H(3) = 10.301, p = 0.016), total NIH-CPSI/GUPI score (H(3) = 42.150, p = 0.000), and quality of life (H(3) = 48.638, p = 0.000). Conclusions: COVID-19 pandemic provoked several alterations in everyday life. Although general lockdown, quarantine and social distancing have been necessary to prevent virus spreading, this had long term effects on all population in terms of mental and physical health. NIH-CPSI and GUPI scores increased linearly with stress and anxiety levels measured at HDRS, confirming worse LUTS in subjects who suffered anxiety and stress from COVID-19 pandemic

Crossing Eurasia: trans-regional Afghan trading networks in China and beyond

An expanding body of literature in the field of Central Asian studies has brought attention to the problems of considering the region's complex dynamics through the lens of its nation-states. Comparatively less attention has been paid to the role played by trans-regional circulations in connecting parts of Central Asia to the wider world. This paper situates ethnographic work on trans-regional networks of Afghan traders in China, Central Asia, Russia, Ukraine and the UK in relation to the literature on trans-regional connections and circulation societies. Ethnographically it demonstrates the multi-polar nature of these trans-regional networks, and the importance of trading nodes, especially the Chinese city of Yiwu, to their formation and ongoing vitality

The Role of Testosterone in the Elderly: What Do We Know?

Testosterone is the most important hormone in male health. Aging is characterized by testosterone deficiency due to decreasing testosterone levels associated with low testicular production, genetic factors, adiposity, and illness. Low testosterone levels in men are associated with sexual dysfunction (low sexual desire, erectile dysfunction), reduced skeletal muscle mass and strength, decreased bone mineral density, increased cardiovascular risk and alterations of the glycometabolic profile. Testosterone replacement therapy (TRT) shows several therapeutic effects while maintaining a good safety profile in hypogonadal men. TRT restores normal levels of serum testosterone in men, increasing libido and energy level and producing beneficial effects on bone density, strength and muscle as well as yielding cardioprotective effects. Nevertheless, TRT could be contraindicated in men with untreated prostate cancer, although poor findings are reported in the literature. In addition, different potential side effects, such as polycythemia, cardiac events and obstructive sleep apnea, should be monitored. The aim of our review is to provide an updated background regarding the pros and cons of TRT, evaluating its role and its clinical applicability in different domains

The POLIPO Security Framework

Systems of systems are dynamic coalitions of distributed, autonomous and heterogeneous systems that collaborate to achieve a common goal. While offering several advantages in terms of scalability and flexibility, the systems of systems paradigm has a significant impact on systems interoperability and on the security requirements of the collaborating systems. In this chapter we introduce POLIPO, a security framework that protects the information exchanged among the systems in a system of systems, while preserving systems’ autonomy and interoperability. Information is protected from unauthorized access and improper modification by combining context-aware access control with trust management. Autonomy and interoperability are enabled by the use of ontology-based services. More precisely, each authority may refer to different ontologies to define the semantics of the terms used in the security policy of the system it governs and to describe domain knowledge and context information. A semantic alignment technique is then employed to map concepts from different ontologies and align the systems’ vocabularies. We demonstrate the applicability of our solution with a prototype implementation of the framework for a scenario in the maritime safety and security domain