The Family Gomphotheriidae in South America : evidence of molars at northern chilean Patagonia

The Family Gomphotheriidae in South America: evidence of molars at northern chilean Patagonia. We present statistical studies made with ten molars M3 and m3 of south-central Chile, we compared material of gomphotheres Stegomastodon platensis, Stegomastodon waringi and Cuvieronius hyodon of South America. Also we analyze three fragments defense of the Chilean sites of Monte Verde, Mulpulmo and Nochaco. In the statistical analysis it is clear that the molars are very variable in shape, also in size and have a great dispersion, however in bivariate diagrams the molars of Chile were grouped with the molars large (genus Stegomastodon). The discriminant analysis indicates that five m3 are associated with Stegomastodon platensis and two with Cuvieronius hyodon, two M3 are associated with Stegomastodon platensis and one with Stegomastodon waringi. We discuss the sympatric between species S. platensis and C. hyodon in southern Chile.Damos a conocer los estudios estadísticos hechos con diez molares M3 y m3 del centro-sur de Chile, comparados con material de gonfoterios Stegomastodon platensis, Stegomastodon waringi y Cuvieronius hyodon de América del Sur. Además se analizan tres fragmentos de defensa provenientes de los sitios chilenos de Monte Verde, Mulpulmo y Nochaco. En el análisis estadístico es claro que los molares son muy variables en forma, así como en tamaño y presentan una gran dispersión, sin embargo en los diagramas bivariantes la mayoría de los molares de Chile se agrupan con los molares de talla grande (del género Stegomastodon). Los análisis discriminantes indican que de los siete m3, cinco se asocian a Stegomastodon platensis y dos a Cuvieronius hyodon. De los tres M3, dos se asocian con la especie Stegomastodon platensis y uno con Stegomastodon waringi. Se discute la probable simpatría de las especies S. platensis y C. hyodon en el sur de Chile.Esta contribución científica ha sido parcialmente financiada por el proyecto FONDECYT 1100555(2010-2012) y el proyecto FNDR de la Región de Los Lagos 2308-56-LE07 (2007-2008), y CGL2010-19116/BOS de la DGCYT de España (MTA).Peer reviewe

Sites for Gamma-ray Astronomy in Argentina

We have searched for possible sites in Argentina for the installation of large air Cherenkov telescope arrays and water Cherenkov systems. At present seven candidates are identified at altitudes from 2500 to 4500 m. The highest sites are located at the Northwest of the country, in La Puna. Sites at 2500 and 3100 m are located in the West at El Leoncito Observatory, with excellent infrastructure. A description of these candidate sites is presented with emphasis on infrastructure and climatology.Comment: Submitted to Proceedings of "4th Heidelberg International Symposium on High Energy Gamma-Ray Astronomy 2008

A New Kind of Quinonic-Antibiotic Useful Against Multidrug-Resistant S. aureus and E. faecium Infections

Indexación: Scopus.A rapid emergence of resistant bacteria is occurring worldwide, endangering the efficacy of antibiotics and reducing the therapeutic arsenal available for treatment of infectious diseases. In the present study, we developed a new class of compounds with antibacterial activity obtained by a simple, two step synthesis and screened the products for in vitro antibacterial activity against ATCC® strains using the broth microdilution method. The compounds exhibited minimum inhibitory concentrations (MIC) of 1⁻32 μg/mL against Gram-positive ATCC® strains. The structure⁻activity relationship indicated that the thiophenol ring is essential for antibacterial activity and the substituents on the thiophenol ring module, for antibacterial activity. The most promising compounds detected by screening were tested against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VREF) clinical isolates. We found remarkable activity against VREF for compounds 7 and 16, were the MIC50/90 were 2/4 µg/mL and 4/4 µg/mL, respectively, while for vancomycin the MIC50/90 was 256/512 µg/mL. Neither compound affected cell viability in any of the mammalian cell lines at any of the concentrations tested. These in vitro data show that compounds 7 and 16 have an interesting potential to be developed as new antibacterial drugs against infections caused by VREF.https://www.mdpi.com/1420-3049/23/7/177

Striatal responsiveness to reward under threat-of-shock and working memory load: A preliminary study.

Reward and stress are important determinants of motivated behaviors. Striatal regions play a crucial role in both motivation and hedonic processes. So far, little is known on how cognitive effort interacts with stress to modulate reward processes. This study examines how cognitive effort (load) interacts with an unpredictable acute stressor (threat-of-shock) to modulate motivational and hedonic processes in healthy adults. A reward task, involving stress with unpredictable mild electric shocks, was conducted in 23 healthy adults aged 20-37 (mean age: 24.7 ± 0.9; 14 females) during functional magnetic resonance imaging (fMRI). Manipulation included the use of (a) monetary reward for reinforcement, (b) threat-of-shock as the stressor, and (c) a spatial working memory task with two levels of difficulty (low and high load) for cognitive load. Reward-related activation was investigated in a priori three regions of interest, the nucleus accumbens (NAcc), caudate nucleus, and putamen. During anticipation, threat-of-shock or cognitive load did not affect striatal responsiveness to reward. Anticipated reward increased activation in the ventral and dorsal striatum. During feedback delivery, both threat-of-shock and cognitive effort modulated striatal activation. Higher working memory load blunted NAcc responsiveness to reward delivery, while stress strengthened caudate nucleus reactivity regardless reinforcement or load. These findings provide initial evidence that both stress and cognitive load modulate striatal responsiveness during feedback delivery but not during anticipation in healthy adults. Of clinical importance, sustained stress exposure might go along with dysregulated arousal, increasing therefore the risk for the development of maladaptive incentive-triggered motivation. This study brings new insight that might help to build a framework to understand common stress-related disorders, given that these psychiatric disorders involve disturbances of the reward system, cognitive deficits, and abnormal stress reactivity

Estudio de Seeing en la Zona del Cerro Champaquí (I)

Resumen: Se reportan los resultados del estudio más reciente de seeing que hemos realizado en la zona del Cerro Champaquí (2800 m) en el cordón de las Sierras Grandes en la Provincia de Córdoba. Se describe además, el dispositivo DIMM de alta frecuencia construido para este trabajo. Este instrumento se empleó en otros muestreos de seeing realizados en las provincias de San Juan y San Luis como parte de un proyecto de búsqueda de sitios con muy baja turbulencia atmosférica y adecuados para observaciones con óptica activa y adaptable en el rango infrarrojo cercano, iniciado en 2006. Dos de estos sitios han sido monitoreados un total de 46 noches distribuidas en seis meses del periodo 2011-2012. Los resultados indican que se darían condiciones de seeing estable, inferior al segundo de arco por prolongados períodos de tiempo, en al menos un sitio del cordón montañoso del SO de Córdoba y NE de San Luis.Abstract: Abstract. We report the results of the most recent seeing feasibility study performed in the region of Cerro Champaquí (2800 m) at the mountain range of Sierras Grandes at the Province of Córdoba. We also describe the high frequency DIMM device built for this and other seeing samplings obtained at the provinces of San Juan, San Luis and Córdoba. This work is part of a long term project started in 2006, in search of sites of very low turbulence and suited for near infrared telescopes with active and adaptive optics. Two of the sites have been monitored during a total of 46 nights distributed in six months of the period 2011-2012. The preliminary results suggest the existence of ‘sub-arcsecond’ seeing conditions during extended periods of time in at least one location in the mountain range in the SW of Córdoba and NE of San Luis provinces.www.astronomiaargentina.orgpublishedVersionFil: Díaz, Rubén Joaquín. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina.Fil: Díaz, Rubén Joaquín. Conicet, Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Argentina.Meteorología y Ciencias Atmosférica

Polycystic ovary syndrome

The document attached has been archived with permission from the editor of the Medical Journal of Australia. An external link to the publisher’s copy is included.Polycystic ovary syndrome (PCOS) affects 5-20% of women of reproductive age worldwide. The condition is characterized by hyperandrogenism, ovulatory dysfunction and polycystic ovarian morphology (PCOM) - with excessive androgen production by the ovaries being a key feature of PCOS. Metabolic dysfunction characterized by insulin resistance and compensatory hyperinsulinaemia is evident in the vast majority of affected individuals. PCOS increases the risk for type 2 diabetes mellitus, gestational diabetes and other pregnancy-related complications, venous thromboembolism, cerebrovascular and cardiovascular events and endometrial cancer. PCOS is a diagnosis of exclusion, based primarily on the presence of hyperandrogenism, ovulatory dysfunction and PCOM. Treatment should be tailored to the complaints and needs of the patient and involves targeting metabolic abnormalities through lifestyle changes, medication and potentially surgery for the prevention and management of excess weight, androgen suppression and/or blockade, endometrial protection, reproductive therapy and the detection and treatment of psychological features. This Primer summarizes the current state of knowledge regarding the epidemiology, mechanisms and pathophysiology, diagnosis, screening and prevention, management and future investigational directions of the disorder.Robert J Norman, Ruijin Wu and Marcin T Stankiewic