Prompt photon yield and v2v_2 coefficient from gluon fusion induced by magnetic field in heavy-ion collision

We compute the production of prompt photons and the $v_2$ harmonic coefficient in relativistic heavy-ion collisions induced by gluon fusion in the presence of an intense magnetic field, during the early stages of the reaction. The calculations take into account several parameters which are relevant to the description of the experimental transverse momentum distribution, and elliptic flow for RHIC and LHC energies. The main imput is the strength of the magnetic field which varies in magnitude from 1 to 3 times the pion mass squared, and allows the gluon fusion that otherwise is forbidden in the absence of the field. The high gluon occupation number and the value of the saturation scale also play an important role in our calculation, as well as a flow velocity and geometrical factors. Our results support the idea that the origin of at least some of the photon excess observed in heavy-ion experiments may arise from magnetic field induced processes, and gives a good description of the experimental data.Comment: 6 pages, 2 figures, conference paper from ISMD 201

Freshwater Crustaceans Decadpos: An Important Resource of Guatemala

Guatemala is a mega diversity country because it has several ecosystems and the physiography has a high diversity. However, the local population uses this biodiversity as a natural resource of food mainly. The country had three main drainage slopes for their rivers and aquatic reservoirs with several basins (the Gulf of Mexico, the Caribbean Sea, and the Pacific Sea). In these slopes, crayfish, freshwater prawns, and crabs compose the aquatic biological resources. Several fieldtrips were performed around these slopes in order to identify the species which were used as natural aquatic resources and verify if the diversity supports the food needs of the local population. Our findings were that the country has at least four crayfish species of genus Procambarus spp., those living in the high and middle altitude areas. Five freshwater prawn species with abbreviated larval development of genus Macrobrachium, that is, Macrobrachium cemai were also found. The bigger species of Macrobrachium was also identified on the three slopes as Macrobrachium americanum, Macrobrachium tenellum, Macrobrachium occidentale, and Macrobrachium digueti on the Pacific slope, while on the Gulf of Mexico and the Caribbean Sea, Macrobrachium carcinus, Macrobrachium acanthurus, Macrobrachium heterochirus, Macrobrachium olfersii, and Macrobrachium hobbsi were recorded, and therefore, the nonnative species Macrobrachium rosenbergii; with respect to other shrimps, Palaemon pandaliformis, Palaemonetes octaviae, and atyids as Atya scabra and Potimirim glabra were found. According to the freshwater crabs, the Pseudothelphusidae family is the best to represent in comparison with Trichodactylidae where only one population was recorded. Also, we register the uses of these species around the main markets in the country and we found two main ways: the first one is for the bigger species of freshwater prawns and crabs that are offered very expensive in kilogram and are almost offered in restaurants as exclusive dishes. The second one is more for the local consumption, and many families of fishery species that include crayfishes, freshwater prawns with abbreviated larval development, and smaller crabs, and so on, are sometimes found in the markets, with the prices being cheaper and can be bought only by the local people. Our findings show that Guatemala has an enormous potential in the crustaceans decapods for use as natural aquatic resources as protein sources at low cost, especially for the families with low economical level

The Habitat Types of Freshwater Prawns (Palaemonidae: <em>Macrobrachium</em>) with Abbreviated Larval Development in Mesoamerica (Mexico, Guatemala and Belize)

The freshwater prawns of genus Macrobrachium with abbreviated larval development have been reported from a diversity of freshwater habitats (caves, springs and primary streams from so-long basins). Here we analysed 360 sites around the Mesoamerican region (Mexico, Guatemala and Belize). At each site, we measured temperature, salinity oxygen dissolved, pH, altitude and water flow velocity values. We documented the riparian vegetation and occurrence and abundance of Macrobrachium populations. All these values were analysed by multi-dimensional scaling and principal components analysis in order to identify key features of the environmental data that determine the habitat types and habitat diversity. The results show that there are Macrobrachium populations in 70 sites inhabiting two main habitats: Lotic and Lentic; and each one have fours subhabitat types. All are defined by altitude range and water velocity that involve the temperature and oxygen variables. In some specific areas, the karstic values on salinity and pH defined some groups. Within the lentic habitats, we identified the following subhabitats: (1) temperate streams, (2) neutral streams, (3) high dissolved oxygen, (4) multifactorial; and for lotic habitats, we identified: (5) water high carbonate, (6) moderate dissolved oxygen, (7) low dissolved oxygen, and (8) high altitude streams. All these subhabitats are located on the drainage basin to the Atlantic Sea, including places from 50 to 850 meters above sea levels and have specifically ranges from temperature, water velocity, pH and salinity for some cases. Also, the geological analysis from the basins where the Macrobrachium inhabit is located showed that the geological faults align with these habitat subdivisions. In this chapter, we discuss the environmental heterogeneity, morphological plasticity and their relationship to physiographic regions across the species ranges

Tropical Subterranean Ecosystems in Mexico, Guatemala and Belize: A Review of Aquatic Biodiversity and Their Ecological Aspects

The subterranean ecosystems in tropical areas of Mexico, North of Guatemala & Belize are very abundant because the karstic soil that allow these formations are the main composition in the Yucatán Peninsula and several mountains systems in these countries; also, they have a strong relationship with tropical forest adjacent where the main energy into the caves have an alloctonous origin. In these three countries there are three different cave conditions: a) freshwater semi-dry caves, b) flooded freshwater systems and c) anchialine systems. Mainly crustaceans and freshwater fishes are the major representative group in the aquatic diversity in these systems because the anchialine members are restricted to Yucatán Peninsula and Islands adjacent. Around 5000 entries to subterranean world there are among these countries, where the Yucatan Peninsula is the area with major caves or cenotes in comparison with southern of Mexico, North of Guatemala and Belize. Into these systems are possible found crustaceans and fishes from different families. The objective of this paper is present a review of these systems according with each karstic areas and show the current map including the location of each systems; as well their subterranean aquatic biodiversity and, finally discuss the relationships among these different areas using their biological aquatic richness in consideration with ecological subterranean conditions

Obtención de biodiesel a partir de grasa residual de pollo

Revista Ciencias E Ingeniería al Día No.1 Vol.7 (2012). Pág. 62 - 67En este artículo se presenta un estudio sobre la obtención de biodiesel mediante la transesterificación de residuos grasos de desecho de pollo por medio de una catálisis alcalina variando el tipo de alcohol usado en el proceso. El rendimiento en el proceso de extracción de la grasa de desecho del pollo es del 70.5%, además, al evaluar las características del biodiesel obtenido y el rendimiento de las reacciones de transesterificación, se pudo concluir respecto al rendimiento de la reacción que fue mayor utilizando metanol, con el cual se obtuvo un rendimiento del 96% en comparación con un 65% con el etanol, por lo que se plantea como una alternativa viable desde el punto de vista técnico, permitiendo la valorización de estos desechos orgánicos

Potential Neuroprotective Effect of the Endocannabinoid System on Parkinson’s Disease

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by alterations in motor capacity resulting from a decrease in the neurotransmitter dopamine due to the selective death of dopaminergic neurons of the nigrostriatal pathway. Unfortunately, conventional pharmacological treatments fail to halt disease progression; therefore, new therapeutic strategies are needed, and currently, some are being investigated. The endocannabinoid system (ECS), highly expressed in the basal ganglia (BG) circuit, undergoes alterations in response to dopaminergic depletion, potentially contributing to motor symptoms and the etiopathogenesis of PD. Substantial evidence supports the neuroprotective role of the ECS through various mechanisms, including anti-inflammatory, antioxidative, and antiapoptotic effects. Therefore, the ECS emerges as a promising target for PD treatment. This review provides a comprehensive summary of current clinical and preclinical evidence concerning ECS alterations in PD, along with potential pharmacological targets that may exert the protection of dopaminergic neurons

Promp photon yield and υ2 coefficent from gluon fusion induced by magnetic field in heavy-ion collisions

We compute the production of prompt photons and the υ2 harmonic coefficient in relativistic heavy-ion collisions induced by gluon fusion in the presence of an intense magnetic field, during the early stages of the reaction. The calculations take into account several parameters which are relevant to the description of the experimental transverse momentum distribution, and elliptic flow for RHIC and LHC energies. The main imput is the strenght of the magnetic field which varies in magnitude from 1 to 3 times the pion mass squared, and allows the gluon fusion that otherwise is forbidden in the absence of the field. The high gluon occupation number and the value of the saturation scale also play an important role in our calculation, as well as a flow velocity and geometrical factors. Our results support the idea that the origin of at least some of the photon excess observed in heavy-ion experiments may arise from magnetic field induced processes, and gives a good description of the experimental data

Effect of Ivabradine on Endothelial Function in Diastolic and Right Heart Failure Patients

Background. Ivabradine is an If ion current inhibitor that has proved to reduce mortality in patients with systolic heart failure by slowing heart rate without decreasing myocardial contractility. Photoplethysmography is a simple, low-cost optical technique that can evaluate vascular function and detect changes in blood flow, pulse, and swelling of tissular microvascular space. Objective. To evaluate the effect of ivabradine on endothelial function by photoplethysmography in diastolic and right heart failure patients. Methodology. 15 patients were included (mean age of 78.1 ± 9.2 years) with optimally treated diastolic and right heart failure. They underwent photoplethysmography before and after induced ischemia to evaluate the wave blood flow on the finger, using the maximum amplitude time/total time (MAT/TT) index. Two measurements were made before and after oral Ivabradine (mean 12.5 mg a day during 6 months of followup). Results. In the study group, the MAT/TT index was 29.1 ± 2.2 versus 24.3 ± 3.2 () in basal recording and 30.4 ± 2.1 versus 23.3 ± 2.9 (), before versus after ischemia and before versus after Ivabradine intervention, respectively. Conclusions. Ivabradine administration improves endothelial function (shear stress) in diastolic and right heart failure patients