Continuous and Discontinuous Phase Transitions in the evolution of a polygenic trait under stabilizing selective pressure

The presence of phenomena analogous to phase transition in Statistical Mechanics, has been suggested in the evolution of a polygenic trait under stabilizing selection, mutation and genetic drift. By using numerical simulations of a model system, we analyze the evolution of a population of $N$ diploid hermaphrodites in random mating regime. The population evolves under the effect of drift, selective pressure in form of viability on an additive polygenic trait, and mutation. The analysis allows to determine a phase diagram in the plane of mutation rate and strength of selection. The involved pattern of phase transitions is characterized by a line of critical points for weak selective pressure (smaller than a threshold), whereas discontinuous phase transitions, characterized by metastable hysteresis, are observed for strong selective pressure. A finite size scaling analysis suggests the analogy between our system and the mean field Ising model for selective pressure approaching the threshold from weaker values. In this framework, the mutation rate, which allows the system to explore the accessible microscopic states, is the parameter controlling the transition from large heterozygosity (disordered phase) to small heterozygosity (ordered one).Comment: 8 pages, 7 figures, 1 tabl

Insidious onset of Pisa syndrome after rasagiline therapy in a patient with Parkinson’s disease

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Continuous monitoring of cerebral oxygen saturation in elderly patients undergoing major abdominal surgery minimizes brain exposure to potential hypoxia

to develop cerebral desaturation because of the reduced physiologic reserve that accompanies aging. To evaluate whether monitoring cerebral oxygen saturation (rSO2) minimizes intraoperative cerebral desaturation, we prospectively monitored rSO2 in 122 elderly patients undergoing major abdominal surgery with general anesthesia. Patients were randomly allocated to an intervention group (the monitor was visible and rSO2 was maintained at 75% of preinduction values; n 56) or a control group (the monitor was blinded and anesthesia was managed routinely; n 66). Cerebral desaturation (rSO2 reduction 75% of baseline) was observed in 11 patients of the treatment group (20%) and 15 patients of the control group (23%) (P 0.82). Mean (95% confidence intervals) values of mean rSO2 were higher (66% [64%–68%]) and the area under the curve below 75% of baseline (AUCrSO2275% of baseline) was lower (0.4 min% [0.1– 0.8 min%]) in patients of the treatment group than in patients of the control group (61% [59%–63%] and 80 min% [2–144 min%], respectively; P 0.002 and P 0.017). When considering only patients developing intraoperative cerebral desaturation, a lower Mini Mental State Elimination (MMSE) score was observed at the seventh postoperative day in the control group (26 [25–30]) than in the treatment group (28 [26 –30]) (P 0.02), with a significant correlation between the AUCrSO2 75% of baseline and postoperative decrease in MMSE score from preoperative values (r20.25, P0.01). Patients of the control group with intraoperative cerebral desaturation also experienced a longer time to postanesthesia care unit (PACU) discharge (47 min [13–56 min]) and longer hospital stay (24 days [7–53] days) compared with patients of the treatment group (25 min [15–35 min] and 10 days [7–23 days], respectively; P 0.01 and P 0.007). Using rSO2 monitoring to manage anesthesia in elderly patients undergoing major abdominal surgery reduces the potential exposure of the brain to hypoxia; this might be associated with decreased effects on cognitive function and shorter PACU and hospital stay

Aves del departamento del Valle del Cauca, Colombia

The avifauna of the department of Valle del Cauca, Colombia, has been one of the best studied biological groups in Colombia since the late 19th century. As a result of these information compilations, estimates of species richness range between 818 and 1025 species. We collected information on bird records from different sources and obtained a list of 989 confirmed bird species for the department and 13 species that were listed as potentially present. We found eight introduced species that have no published records or are anecdotal in Colombia. Future expeditions or investigations should focus on filling the information gaps on birds in the Garrapatas river canyon, the area south of Buenaventura and the Central mountain range.La avifauna del departamento del Valle del Cauca, Colombia, ha sido uno de los grupos biológicos mejor estudiados en Colombia desde finales del siglo XIX. Producto de estos ejercicios de compilación de información, los estimados de la riqueza de especies varían entre 818 y 1025 especies. Recopilamos información de registros de aves de diferentes fuentes y obtuvimos un listado de 989 especies de aves confirmadas para el departamento y 13 especies que fueron catalogadas como potencialmente presentes. Documentamos ocho especies introducidas que no tienen registros publicados o son anecdóticos en Colombia. Futuras expediciones o investigaciones deberían enfocarse en llenar los vacíos de información de aves que se concentran en el cañón del río Garrapatas, y el área al sur de Buenaventura y la cordillera Central

VST project: mechanical design optimization

The VLT Survey Telescope (VST) is a cooperative program between the European Southern Observatory (ESO) and the INAF Capodimonte Astronomical Observatory (OAC), Naples, for the study, design, and realization of a 2.6-m wide-field optical imaging telescope to be operated at the Paranal Observatory, Chile. The VST has been specifically designed to carry out stand-alone observations in the UV to I spectral range and to supply target databases for the ESO Very Large Telescope (VLT). The telescope design, manufacturing and integration are responsibility of TWG and have been carried out on the base of a model of optimized design not only for mechanics but for all telescope subsystems. The paper is an overview on the telescope mechanical design and optimization

IL TRATTAMENTO DELLE DISLIPIDEMIE NELLA PREVENZIONE PRIMARIA DELLE MALATTIE CARDIOVASCOLARI: LE INDICAZIONI PER LA PRATICA CLINICA

Le dislipidemie rappresentano uno dei più importanti fattori causali della arteriosclerosi e delle sue complicanze d’organo, come l’infarto del miocardico, l’ictus e la vasculopatia periferica. Il loro appropriato trattamento rappresenta la base degli interventi di prevenzione primaria delle malattie cardiovascolari su base ischemica. In generale, per dislipidemia si intende una condizione clinica nella quale sono presenti alterazioni qualitative e/o quantitative dei lipidi e delle lipoproteine plasmatiche

Sardinia Array Demonstrator: Instrument Overview and Status

In the framework of the Square Kilometer Array (SKA) project, the Italian Institute for Astrophysics (INAF) has addressed several efforts in the design and prototyping of aperture arrays for low-frequency radio astronomical research. The Sardinia Array Demonstrator (SAD) is a national project aimed to develop know-how in this area and to test different architectural technologies and calibration algorithms. SAD consists of 128 prototypical dual-polarized Vivaldi antennas designed to operate at radio frequencies below 650 MHz. The antennas will be deployed at the Sardinia Radio Telescope’s site with a versatile approach able to provide two different array configurations: (i) all antennas grouped in one large station or (ii) spread among a core plus few satellite stations. This paper provides an overview of the SAD project from an instrumental point of view, and illustrates its status after 2 years from its start