Fecundity of Litopenaeus setiferus, Farfantepenaeus aztecus and F. duorarum, in the Southwestern Gulf of Mexico

Fecundity of white shrimp, Litopenaeus setiferus, brown shrimp, Farfantepenaeus aztecus, and pink shrimp F. duorarum and relationships to gonad weights and total and carapace length were estimated. Ovigerous females were collected in the southern Gulf of Mexico in February, May, August and November 1993. Fecundity was estimated by means of a gravimetric method. The equations relating fecundity to total weight and fecundity to gonad weight were linear in the 3 species. However, an exponential relationship was found between fecundity and carapace length in L. setiferus and F. aztecus. Of the relationships examined, gonad weight was considered a more precise indicator of fecundity. Fecundity estimates ranged from 70,647 to 558,270 eggs for 0.203 and 5.639 g gonad weight of L. setiferus, from 23,298 to 494,292 eggs for 0.061 to 2.561 g gonad weight in F. aztecus and from 138,618 to 225,543 eggs for 0.120 to 0.998 g gonad weight in F. duorarum

Evaluation of Porin Interaction with Adenine Nucleotide Translocase and Cyclophilin-D Proteins after Brain Ischemia and Reperfusion

Objective (s) Porin is a mitochondrial outer membrane channel, which usually functions as the pathway for the movement of various substances in and out of the mitochondria and is considered to be a component of the permeability transition (PT) pore complex that plays a role in the PT. We addressed the hypothesis that porin interacts with other mitochondrial proteins after ischemic injury.Materials and MethodsFor this purpose, we used in vivo 4-vessel occlusion model of rat brain and porin purification method by hydroxyapatite column. After SDS gel electrophoresis and silver nitrate staining, Western blotting was done for porin, adenine nucleotide translocase and cyclophilin-D proteins.Results Porin was purified from mitochondrial mixture in ischemic brain and control groups. Investigation of interaction of adenine nucleotide transposes (ANT) and cyclophilin-D with porin by Western blotting showed no proteins co-purified with porin from injured tissues.Conclusion The present study implies that there may not be interaction between porin, and ANT or cyclophilin-D, and if there is any, it is not maintained during the purification procedure

Basal ganglia, drug addiction and the neuroscience of maladaptive habits

The mammalian brain has developed memory systems mediating rigid, yet evolutionarily adaptive patterns of responding to invariant environmental stimuli and internal demands. Such memory systems promote the recall of specific response templates and the execution of inflexible actions to liberate buffering capacity for performing conscious, explicit cognitive processing. The dopamine-innervated neostriatum is central to the ability to learn such consistent associations between stimuli and actions implicitly. Controlled by their outcome when initially learned, actions succumb through iteration to the influence of triggering stimuli and progressively detach themselves from the pleasurable results originally produced, thereby becoming pervasive habits. This might be the case for drug-seeking and drug-taking behaviours, actions learned in part through dopamine-dependent drug-induced reinforcement when the drug is first experienced. With extended drug use, however, drugseeking actions might become conditioned to, and triggered by, specific exteroceptive stimuli and/or affective states, gradually becoming irrepressible forms of responding. We will review neuroanatomical, neuropharmacological and behavioural evidence suggesting that the basal ganglia play a prominent role in the shaping of drug addiction, here regarded as a pathological modification of otherwise adaptive habit learning systems mediated by the basal ganglia.peer-reviewe

Teaching-Learning Anglophone Cultures at the University of Pedagogical Sciences of Holguín and at the ELC of Shantou University: A Comparative Study

This paper presents a comparative study of the teaching-learning process of Anglophone cultures through the English as a foreign language programs of Shantou University, Guangdong, China, and Universidad de Ciencias Pedagógicas “José de la Luz y Caballero”, Holguín, Cuba. As criteria for the comparison, the authors have selected the objectives, teaching methods, and resources of the two institutions. The comparative analysis allowed for the determination of the main trends common to both universities: the teaching of language as a means to an end, the active participation of faculties in the elaboration of teaching materials and textbooks for the specific courses they teach, the validity of research work aimed at improving the teaching resources for the EFL courses offered at both universities, the use of the communicative approach as a general method for the teaching-learning process, and the development of co-curricular activities to enhance the teaching-learning of cultural elements. The analysis also allowed for a reflection on how the distinct departmental/institutional structures of the two schools may lead to some significant differences in terms of educational focus. Finally, the analysis provoked questions concerning the balance between culture teaching-learning and intercultural communication training

On a Simple General Principle of Brain Organization

A possible framework to characterize nervous system dynamics and its organization in conscious and unconscious states is introduced, derived from a high level perspective on the coordinated activity of brain cell ensembles. Some questions are best addressable in a global framework and here we build on past observations about the structure of configurations of brain networks in conscious and unconscious states and about neurophysiological results. Aiming to bind some results together into some sort of coherence with a central theme, the scenario that emerges underscores the crucial importance of the creation and dissipation of energy gradients in brain cellular ensembles resulting in maximization of the configurations in the functional connectivity among those networks that favor conscious awareness and healthy conditions. These considerations are then applied to indicate approaches that can be used to improve neuropathological syndromes.Fil: Perez Velazquez, Jose L.. Ronnin Institute; Estados UnidosFil: Mateos, Diego Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Matemática Aplicada del Litoral. Universidad Nacional del Litoral. Instituto de Matemática Aplicada del Litoral; ArgentinaFil: Guevara Erra, Ramon. Laboratoire Psychologie de la Perception, Cnrs; Franci

Afectación del sistema cardiovascular en la infección por SARS-CoV-2

Introduction: COVID-19 is an emerging disease with global incidence, which exhibits a greater number of complications in patients with comorbidities, mainly in those with a history of cardiovascular disease.Objective: to describe the implications of COVID-19 in the cardiovascular system.Method: A review of the literature was conducted in the MEDLINE, SciELO, JAMA and Elsevier databases, recovering 35 articles, which were taken as the basis for the present review. The combination of terms using search formulas was used to retrieve articles.Development: COVID-19 can be variable in correspondence with the presentation form and accompanying symptoms, as well as the recipient's immune response. SARS-CoV-2 binds to cells through the viral spike structural protein that binds to the angiotensin-converting enzyme 2 receptor from viral receptors; therefore, hypertensive patients or those with other cardiovascular conditions have a higher risk of developing severe forms of COVID-19. Among the cardiovascular diseases associated with infection by a coronavirus, myocarditis, arrhythmias, acute myocardial infarction and heart failure stand out.Conclusions: the main cardiovascular implications in patients with COVID-19 are arrhythmia, thromboembolic disease, myocarditis, heart failure of acute onset and myocardial infarction, which condition a more serious picture of the disease. The inflammatory response, hemodynamic changes secondary to the viral process, as well as hypoxemia, constitute mechanisms of negative impact on cardiovascular health, leading to the development of acute cardiac injury.Introducción: la COVID-19 es una enfermedad emergente con incidencia global, que exhibe mayor número de complicaciones en pacientes con comorbilidades, principalmente en aquellos con antecedentes de enfermedades cardiovasculares.Objetivo: describir las implicaciones de la COVID-19 en el sistema cardiovascular.Método: Se realizó una revisión de la literatura en las bases de datos MEDLINE, SciELO, JAMA y Elsevier, recuperándose 35 artículos, los cuales se tomaron de base para la presente revisión. Se empleó la combinación de términos mediante fórmulas de búsqueda para recuperar los artículos.Desarrollo: la COVID-19 puede ser variable en correspondencia con la forma de presentación y síntomas acompañantes, así como la respuesta inmunitaria del receptor. El SARS-CoV-2  se une a las células a través de la proteína estructural viral de espiga que se une al receptor de la enzima convertidora de angiotensina 2 a partir de receptores virales; por ello, los pacientes hipertensos o  con  otras  afecciones cardiovasculares tienen un mayor riesgo de desarrollar formas severas de COVID-19.  Dentro de las afectaciones cardiovasculares asociados a la infección por un coronavirus destacan la miocarditis, arritmias, infarto agudo de miocardio e insuficiencia cardíaca.Conclusiones: Las principales implicaciones cardiovasculares en los pacientes con COVID-19 son arritmia, enfermedad tromboembólica, miocarditis, insuficiencia cardiaca de inicio agudo e infarto de miocardio, las cuales condicionan un cuadro más grave de la enfermedad. La respuesta inflamatoria, los cambios hemodinámicos secundarios al proceso viral, así como la hipoxemia, constituyen mecanismos de repercusión negativa sobre la salud cardiovascular, llevando al desarrollo de lesión cardiaca aguda.

Mining in Mexico: forms of accumulation and environmental effects

A la acumulación originaria fue la primera negación de la propiedad individual basada en el trabajo, dando paso a la propiedad privada de los medios de producción y la posibilidad de apropiarse del trabajo de los campesinos que fueron despojados de sus bienes. A partir de la disolución de la propiedad colectiva de la tierra, y de otros bienes comunes.La actividad minera en México ha sido muy importante, por el valor de los recursos minerales. Se emplean formas de acumulación que se han instrumentado para la generación de riqueza a costa de la segregación como efecto ambiental. Este artículo aborda los modelos de acumulación para poder comprender cómo se maneja la actividad minera en México, implementando un modelo extractivo exportador que admite la imposición de una lógica de saqueo, contaminación y recolonización sobre los recursos naturales y las formas de vida. En los estudios de minería, la acumulación de capital es respaldado por estrategias como el despojo que permiten la implementación de diferentes procesos de extracción, lo que ha provocado a lo largo de la historia efectos ambientales. Esta última etapa denominada por desposesión, abordada por David Harvey, genera efectos sociales. El objetivo es abordar los modelos de acumulación, las características, los mecanismos de despojo, las leyes y los reglamentos que facilitan la inversión minera en el país. La metodología empleada para esta investigación es a través del materialismo histórico donde algunas de las categorías teóricas centrales son las relaciones y fuerzas de producción, la explotación y la lucha de clases que trae como resultado una forma de vida.Universidad autónoma del Estado de México Consejo Nacional de Ciencia y Tecnología (Beca Nacional

Detection of satellite remnants in the Galactic Halo with Gaia III. Detection limits for Ultra Faint Dwarf Galaxies

We present a method to identify Ultra Faint Dwarf Galaxy (UFDG) candidates in the halo of the Milky Way using the future Gaia catalogue and we explore its detection limits and completeness. The method is based on the Wavelet Transform and searches for over-densities in the combined space of sky coordinates and proper motions, using kinematics in the search for the first time. We test the method with a Gaia mock catalogue that has the Gaia Universe Model Snapshot (GUMS) as a background, and use a library of around 30 000 UFDGs simulated as Plummer spheres with a single stellar population. For the UFDGs we use a wide range of structural and orbital parameters that go beyond the range spanned by real systems, where some UFDGs may remain undetected. We characterize the detection limits as function of the number of observable stars by Gaia in the UFDGs with respect to that of the background and their apparent sizes in the sky and proper motion planes. We find that the addition of proper motions in the search improves considerably the detections compared to a photometric survey at the same magnitude limit. Our experiments suggest that Gaia will be able to detect UFDGs that are similar to some of the known UFDGs even if the limit of Gaia is around 2 magnitudes brighter than that of SDSS, with the advantage of having a full-sky catalogue. We also see that Gaia could even find some UFDGs that have lower surface brightness than the SDSS limit.Comment: Accepted for publication in MNRA