Graph-Controlled Insertion-Deletion Systems

In this article, we consider the operations of insertion and deletion working in a graph-controlled manner. We show that like in the case of context-free productions, the computational power is strictly increased when using a control graph: computational completeness can be obtained by systems with insertion or deletion rules involving at most two symbols in a contextual or in a context-free manner and with the control graph having only four nodes.Comment: In Proceedings DCFS 2010, arXiv:1008.127

Biological nitrogen removal over nitritation/denitritation using phenol as carbon source

A laboratory scale activated sludge sequencing batch reactor was operated in order to obtain total removal of influent ammonia (200; 300 and 500 mg NH3-N.L-1) with sustained nitrite accumulation at the end of the aerobic stages with phenol (1,000 mg C6H5OH.L-1) as the carbon source for denitrifying microorganisms during the anoxic stages. Ammonia removal above 95% and ratios of (NO2--N / (NO2--N + NO3--N)) ranging from 89 to 99% were obtained by controlling the dissolved oxygen concentration (1.0 mg O2.L-1) and the pH value of 8.3 during the aerobic stages. Phenol proved to be an adequate source of carbon for nitrogen removal via nitrite with continuous feeding throughout part of the anoxic stage. Nitrite concentrations greater than 70.0 mg NO2--N.L-1 inhibited the biological denitritation process.FAPESP (The State of São Paulo Research Foundation

Temporal variation and size class distribution in a herpetological assemblage from Córdoba, Argentina

Desde el punto de vista de la conservación, conocer la abundancia, la diversidad, y los patrones de actividad de un ensamble herpetológico son medulares para comprender la dinámica de la comunidad y el modo de cómo es utilizado el hábitat. En este proyecto propusimos cuatro hipótesis nulas: 1) La frecuencia de captura de cada una de las especies será similar en los dos años relevados. 2) La frecuencia de capturas de cada especie es similar durante los meses estudiados. 3) La actividad de cada especie es similar a la actividad del resto del ensamble. 4) Las proporciones de cada grupo etario de cada especie se mantienen constantes en el tiempo. Durante este estudio fueron colectadas diecinueve especies, diez especies de Amphibia distribuidas en cuatro familias y nueve especies de Squamata distribuidas en siete familias. En hábitats relativamente complicados que poseen una estructura vegetal compleja y presentan patrones de actividad herpetológica irregular, el uso de trampas de caída resulta uno de los pocos métodos eficientes para la evaluación de la actividad de animales terrestres. El uso de trampas de caída es un método efectivo para realizar inventarios herpetológicos pero los resultados deben ser tratados con precaución porque este método captura algunas especies más fácilmente que otras. Los principales resultados obtenidos por este estudio fueron: La hipótesis 1 fue rechazada, para todas las especies exceptuando a Mabuya dorsivittata, que mostró frecuencias de actividad similares en ambos años, la hipótesis 2 también fue rechazada porque todas las especies mostraron significativas diferencias de actividad temporal. Las especies más variables fueron Odontophrynus americanus y Bufo fernandezae; la más constante Pantodactylus schreibersi. La tercera hipótesis fue rechazada para todas las especies salvo Elachistocleis bicolor que presentó un patrón de actividad similar al ensamble. La hipótesis 4 fue rechazada, los grupos etarios de cada especie cambió temporalmente debido al reclutamiento y el período de reclutamiento varió en y entre especies. Durante el primer período el índice de diversidad mayor se registró en abril 1999 (5.46), durante el segundo período de estudio el mayor índice de diversidad se registró en enero 2000. Este estudio muestra la importancia de los estudios temporalmente extensos y enfatiza la importancia de comprender la variación temporal de la fenología, diversidad y patrones de actividad de los ensambles herpetológicos.From a conservationist perspective, knowledge of the abundance, diversity, and activity patterns of a herpetological assemblage is essential to understand community dynamics and habitat utilization. We proposed four null hypotheses regarding the dynamics of an assemblage of amphibians and reptiles from Argentina: 1) The capture frequency of each species studied is similar during the two years; 2) The capture frequency of each species is similar in every month of each period; 3) The activity of each species is similar to that of every other species and 4) The proportion of each size class for each species is similar throughout the year. During the study, nineteen species were collected: ten species of Amphibia belonging to four families, and nine species of Squamata, distributed among seven families. In relatively complex habitats, with dense vegetation and very irregular herpetological activity, the pitfall method is one of the few efficient ways to evaluate terrestrial animal activity. Pitfall traps are an effective method to perform herpetological inventories, but results must be reported with caution because traps capture some species more easily than others. The main results of this study were: Hypothesis 1 was rejected for all species except Mabuya dosivittata, which showed similar frequencies during both years. Hypothesis 2 was rejected, as all species showed significant seasonal differences. The most variable species were Bufo fernandezae and Odontophrynus americanus; the most constant was Pantodactylus schreibersi. Hypothesis 3 was rejected for all species; except Elachistochleis bicolor that showed a similar activity pattern as the assemblage. Hypothesis 4 was rejected, size groups of each species showed temporal variation due to recruitment and recruitment period varied in and between species. During the first period, the highest diversity index was registered in April 1999 (5.46). During the second year the highest diversity index recorded (6.85) was in January 2000. This study shows the importance of long-term studies for conservation purposes. It also emphasizes the importance of understanding variation of the phenologies of individual species and the variation of activity and diversity within assemblages between years.Asociación Herpetológica Argentina (AHA

Neuroscience Near-Peer-Led Flipped Classroom Improves Student Confidence With Clinical Application of Content and Test-Taking Skills

Introduction The ability to apply knowledge gained in neuroscience coursework to a clinical scenario is found to be difficult by many medical students. Neuroscience is both important for future clinical practice and an area frequently tested on USMLE Step 1 examinations. Methods Second-year medical students created a peer-led flipped classroom to help first-year students practice applying medical neuroscience course information to clinical situations and demonstrate how that information might be tested in board-style questions. The second-year students designed a series of board-style questions that included explanations for both the correct and incorrect answers. We divided the first-year students (n = 80) into small groups during the flipped classroom sessions, where they were led by second-year medical students in discussion about the questions and clinical situations. Results Students reported agreement that the session addressed gaps in their knowledge and provided them with useful critical thinking skills for approaching board-style questions (83% and 81% agreed or strongly agreed, respectively). Discussion The flipped classroom improved student confidence in both applying neuroscience concepts to clinical scenarios and to board-style vignette questions

Multiscale Bone Remodelling with Spatial P Systems

Many biological phenomena are inherently multiscale, i.e. they are characterized by interactions involving different spatial and temporal scales simultaneously. Though several approaches have been proposed to provide "multilayer" models, only Complex Automata, derived from Cellular Automata, naturally embed spatial information and realize multiscaling with well-established inter-scale integration schemas. Spatial P systems, a variant of P systems in which a more geometric concept of space has been added, have several characteristics in common with Cellular Automata. We propose such a formalism as a basis to rephrase the Complex Automata multiscaling approach and, in this perspective, provide a 2-scale Spatial P system describing bone remodelling. The proposed model not only results to be highly faithful and expressive in a multiscale scenario, but also highlights the need of a deep and formal expressiveness study involving Complex Automata, Spatial P systems and other promising multiscale approaches, such as our shape-based one already resulted to be highly faithful.Comment: In Proceedings MeCBIC 2010, arXiv:1011.005

BIOLOGICAL NITROGEN REMOVAL OVER NITRITATION/DENITRITATION USING PHENOL AS CARBON SOURCE

Abstract -A laboratory scale activated sludge sequencing batch reactor was operated in order to obtain total removal of influent ammonia (200; 300 and 500 mg NH 3 -N.

Histone deacetylases as new therapy targets for platinum-resistant epithelial ovarian cancer

Introduction: In developed countries, ovarian cancer is the fourth most common cancer in women. Due to the nonspecific symptomatology associated with the disease many patients with ovarian cancer are diagnosed late, which leads to significantly poorer prognosis. Apart from surgery and radiotherapy, a substantial number of ovarian cancer patients will undergo chemotherapy and platinum based agents are the mainstream first-line therapy for this disease. Despite the initial efficacy of these therapies, many women relapse; therefore, strategies for second-line therapies are required. Regulation of DNA transcription is crucial for tumour progression, metastasis and chemoresistance which offers potential for novel drug targets. Methods: We have reviewed the existing literature on the role of histone deacetylases, nuclear enzymes regulating gene transcription. Results and conclusion: Analysis of available data suggests that a signifant proportion of drug resistance stems from abberant gene expression, therefore HDAC inhibitors are amongst the most promising therapeutic targets for cancer treatment. Together with genetic testing, they may have a potential to serve as base for patient-adapted therapies