Playa del Carmen, Mexico

Technological Institute of Chetumal

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Playa del Carmen, Mexico
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Sabido-Itza M.M.,Technological Institute of Chetumal | Aguilar-Perera A.,Autonomous University of Yucatán | Medina-Quej A.,Technological Institute of Chetumal
Acta Ichthyologica et Piscatoria | Year: 2016

Background. Biological invasions are often listed among the main threats to the ecosystem and are considered drivers of biodiversity loss. The Indo-Pacific lionfish, Pterois volitans (Linnaeus, 1758) (hereafter lionfish), invaded the Atlantic Ocean where it threatens the stability of the marine ecosystem. It would be crucial to know its biological characteristics to understand how environmental parameters could affect its growth. It is also important to continue the earlier efforts of management and control. In this study, we described the L-W and L-L relations and the relative condition factor of lionfish in two natural protected areas in the southern coast of Quintana Roo, Mexico. Materials and methods. Lionfish were captured during 2012 and 2013 from the Reserva de la Biosfera Banco Chinchorro (RBBC) and the Parque Nacional Arrecifes de Xcalak (PNAX). The length-weight relation was calculated based on the equation W = aTLb. The relative condition factor was calculated through the relative weight. Results. A total of 817 lionfish were caught in the frames of this study. In this number, there were 449 individuals from the RBBC (282.1 ± 62.1 mm TL) and 368 from the PNAX (249.2 ± 77.6 mm TL). The L-W relation for lionfish from the RBBC was W = 0.0041 TL3.258 and that for the PNAX was W = 0.0049 TL3.191. There was a significant difference between these relations (ANCOVA, F = 3.91; P = 0.0481). The growth type was positive allometric. The L-L relation was significant. The relative condition factor differed between areas only in 2013, but a high value was determined in 2012. Conclusions. The L-W relations were different between locations (RBBC and PNAX) but no between years. The relative condition factor showed high values (>100) for both locations which may imply that lionfish is in good shape, in the studied location, due to environmental factors providing good food supply and because of the lack of predators. These results may be useful as a baseline to document the population dynamics of lionfish in the region. © 2016, Scientific Society of Szczecin. All rights reserved.


Charruau P.,National Autonomous University of Mexico | Perez-Flores J.,Africam Safari Zoo | Perez-Juarez J.G.,Africam Safari Zoo | Cedeao-Vazquez J.R.,Technological Institute of Chetumal | Rosas-Carmona R.,Technological Institute of Chetumal
Diseases of Aquatic Organisms | Year: 2012

Bacterial cultures and chemical analyses were performed from cloacal and oral swabs taken from 43 American crocodiles Crocodylus acutus and 28 Morelet's crocodiles C. moreletii captured in Quintana Roo State, Mexico. We recovered 47 bacterial species (28 genera and 14 families) from all samples with 51.1% of these belonging to the family Enterobacteriaceae. Fourteen species (29.8%) were detected in both crocodile species and 18 (38.3%) and 15 (31.9%) species were only detected in American and Morelet's crocodiles, respectively. We recovered 35 bacterial species from all oral samples, of which 9 (25.8%) were detected in both crocodile species. From all cloacal samples, we recovered 21 bacterial species, of which 8 (38.1%) were detected in both crocodile species. The most commonly isolated bacteria in cloacal samples were Aeromonas hydrophila and Escherichia coli, whereas in oral samples the most common bacteria were A. hydrophila and Arcanobacterium pyogenes. The bacteria isolated represent a potential threat to crocodile health during conditions of stress and a threat to human health through crocodile bites, crocodile meat consumption or carrying out activities in crocodile habitat. We especially warn about the presence of Salmonella arizonae and S. typhi, which cause enteritis and septicemia in crocodiles and salmonellosis and typhoid fever in humans. The risk of bacterial contamination from crocodiles to humans could increase in the future because of the accelerated destruction of crocodile habitat, which could lead to an augmentation of human-crocodile interactions. Information on bacterial diversity reported here could help in the choice of antibacterial products in case of infections that are of crocodile origin. © Inter-Research 2012.


Conde-Vela V.M.,Technological Institute of Chetumal | Conde-Vela V.M.,Colegio de Mexico
Zootaxa | Year: 2013

The nereidid polychaete genus Namalycastis Hartman, 1959 has been recorded almost exclusively in non-marine environments. This genus includes species having four pairs of tentacular cirri, and its species mainly differ by the relative size of dorsal cirri in posterior chaetigers. Namalycastis occulta n. sp. is described based upon non-mature and mature specimens collected in the intertidal from Chetumal Bay, Quintana Roo, Mexico. Its distinctive features are the lack of notopodial spinigers, eyes, and teeth in the mandibles. Namalycastis borealis Glasby was found in Tamalcab Island, Chetumal Bay and it is the first record for Mexico. Analyses of the intraspecific variability, a key to the known species in the Grand Caribbean region, and commentaries about some taxonomic topics are also included. Copyright © 2013 Magnolia Press.


Queen conch is a gastropod inhabiting the Caribbean Sea, it represents the second largest fishery after the spiny lobster, but it has been extensively captured in the area. In order to know its population status in Chinchorro Bank, we determined conch density changes and its effects on reproductive activities, between July and November 2009. For this, data on conch density, morphology and reproductive activities were obtained from 15 sites within three fishing zones, and compared with previously collected data (1990, 1992, 1994, and 1997). Data showed that adult density decreased with time, from 10 700ind./ha in 1990, to 198ind./h in 2009. Neither egg masses nor spawns were found and mating was only observed once in July 2009. In July, adult (lip>4mm) density in the Southern zone was 23ind./ha whereas in the Northern zone and Central zone densities were 15 and 9ind./ha respectively. In November, density was somewhat higher: Southern zone 96ind./ha; Central zone 39ind./ha and Northern zone had 38ind./ha. In July, mean shell length was 170.80±46.28mm, with a higher median abundance at 180-189mm. In November, higher frequency was 187.63±45.14mm, maximum at 210-219mm interval. For the last 10 years period, mean adult conch densities have diminished in each zone, which might be the main cause of decreased reproductive activities of the conch at Banco Chinchorro. It is therefore an immediate need to analyse the management plan for this species in this Reserve and perhaps to promote a re-population of queen conch and culture activities.


Chavez-Ramirez A.U.,CIDETEQ | Vallejo-Becerra V.,Centro Universitario Cerro Of Las Campanas | Cruz J.C.,Technological Institute of Chetumal | Ornelas R.,Tozzi Renewable Energy SpA | And 3 more authors.
International Journal of Hydrogen Energy | Year: 2013

World fossil fuel reserve is expected to be exhausted in coming few decades. Therefore, the decentralization of energy production requires the design and integration of different energy sources and conversion technologies to meet the power demand for single remote housing applications in a sustainable way under various weather conditions. This work focuses on the integration of photovoltaic (PV) system, micro-wind turbine (WT), Polymeric Exchange Membrane Fuel Cell (PEM-FC) stack and PEM water electrolyzer (PEM-WE), for a sustained power generation system (2.5 kW). The main contribution of this work is the hybridization of alternate energy sources with the hydrogen conversion systems using mid-term and short-term storage models based in artificial intelligence techniques built from experimental data (measurements obtained from the site of interest), this models allow to obtain better accuracy in performance prediction (PVMSE = 8.4%, PEM-FCMSE = 2.4%, PEM-WEMSE = 1.96%, GSRMSE = 7.9%, WTMSE = 14%) with a practical design and dynamic under intelligent control strategies to build an autonomous system. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


Chavez-Ramirez A.U.,CIDETEQ | Cruz J.C.,CIDETEQ | Cruz J.C.,Technological Institute of Chetumal | Espinosa-Lumbreras R.,Autonomous University of Zacatecas | And 3 more authors.
International Journal of Hydrogen Energy | Year: 2013

The Mexican territory has a large potential for renewable energy development, such as geothermal, hydro, biofuels, wind and solar. Thus, a 2.5 kW hybrid power system (solar, wind and hydrogen) was designed and installed to meet the power demand for a stand-alone application at the University of Zacatecas. The hybrid unit integrates three power energy sources -a photovoltaic system (PV), a micro-wind turbine (WT), a prototype of a unitized regenerative fuel cell (URFC) and energy storage devices (batteries)- in addition to their interaction methodology. The main contribution of this work is the URFC integration to a hybrid power system for the production of H2 (water electrolyzer mode) and energy (fuel cell mode). These three energy technologies were connected in parallel, synchronized to the energy storage system and finally coupled to a power conversion module. To achieve the best performance and energy management, an energy management and control strategy was developed to the properly operation of the power plant. A meteorological station that has wireless sensors for the temperature, the humidity, the solar radiation and the wind speed provides the necessary information (in real time) to the monitor and control software, which computes and executes the short and mid-term decisions about the energy management and the data storage for future analysis. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


Balan-Dzul V.,Technological Institute of Chetumal | de Jesus-Navarrete A.,Colegio de Mexico
Revista de Biologia Marina y Oceanografia | Year: 2011

The milk conch Strombus costatus has rarely been studied at population and fisheries level in the Caribbean and Gulf of Mexico. To determine density and population structure of S. costatus at Banco Chinchorro, samplings was conducted using the method of distance during two seasons: summer (October 2008 and July 2009) and winter (November 2008 and February 2009), in order to evaluate the degree of aggregation we use the ratio variance/mean. With the size frequencies, growth parameters were obtained using FISAT II. 157 conchs were recorded, which showed an aggregate distribution. The highest density occurred in the winter season; 172 ind há-1 in the southern zone in November 2008, whereas in the central zone density was 77 ind há-1 in February 2009 and finally 51 ind há-1 in the northern zone in February 2009. The size structure varied between 80-165 mm siphonal length. The highest relative frequency value (FR) was detected in the south ranging between 111-115 mm LS. The infinite maximum length was L∞ = 193.5, and a growth constant K = 0.38 with t0 = -0.51 was calculated. The rate of natural mortality was M = 1.062. The reported densities are higher than those reported in other Caribbean areas; however, the population of S. costatus could not support commercial exploitation at Banco Chinchorro. Densities of S. costatus have not changed over time, so milk conch is not displacing queen conch, which is subject to fisheries.


Barbosa R.,University of Quintana Roo | Sanchez V.M.,University of Quintana Roo | Escobar B.,Research Center Cientifica Of Yucatan | Cruz J.C.,Technological Institute of Chetumal | Toral-Cruz H.,University of Quintana Roo
International Journal of Hydrogen Energy | Year: 2015

Nowadays, society and the economy largely depend on wireless communications because they allow freedom of human activities from spatial and temporal restrictions. To add mobility to this communication technology type, portable communication networks can be implemented to achieve this aim as well as to provide ubiquitous coverage in emergency circumstances. In accordance with the above-mentioned points, we study a photovoltaic-hydrogen system (PVS-H2) for a portable emergency communication system (PECS), which operates in a mobile ad-hoc mesh network. As a case study, a theoretical application on the effects of two hurricanes per year in Cancun, Mexico using real weather data and random dates is presented. A power system was sized to cope with hypothetical emergency communication scenarios. The results show that the PVS-H2 can operate during two hurricanes with an efficacy of 79.14% and a standard deviation of 0.96%. According to the results, the analysis strategy can determine the best configuration to avoid oversizing or undersizing with a small standard deviation. The obtained sizing result ensures that the PVS-H2 supplies adequate energy for the PECS. © 2015 Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


Arias-Gonzalez J.E.,CINVESTAV | Acosta-Gonzalez G.,CINVESTAV | Membrillo N.,CINVESTAV | Garza-Perez J.R.,National Autonomous University of Mexico | Castro-Perez J.M.,Technological Institute of Chetumal
Biodiversity and Conservation | Year: 2012

The assessment of biodiversity in coral reefs requires the application of geographic information systems (GIS), remote sensing and analytical tools in order to make cost-effective spatially explicit predictions of biodiversity over large geographic areas. Here we present a spatially explicit prediction for coral reef fish diversity index, as well as habitat classification according to reef fish diversity index values in Chinchorro Bank Biosphere Reserve, one of the most important plain/atoll type reef systems in the Caribbean. We have used extensive ecological data on depth, fish and habitat characteristics to perform such prediction. Fish species assemblages and different biotic variables of benthic organisms were characterized using visual censuses and video-transects, respectively at 119 sampling stations. The information was integrated in a GIS, along with satellite imagery (LANSDAT 7 ETM+) and a digital bathymetric model. From the recorded data and a hierarchical classification procedure, we obtained nine different classes of habitats. We used a generalized regression analysis and spatial prediction methodology to create predictive maps (GIS layers) of the different reef benthic components, and a second modeling run produced predictive maps of coral reef fish diversity index. Predictive accuracy of the diversity index map presented a good correlation coefficient (r = 0.87), with maximum diversity index values en reefscapes composed of aggregation of coral colonies with seagrass beds. The implementation of our application was successful for the prediction of fish diversity hot spots and surrogate habitats. © 2011 Springer Science+Business Media B.V.


Lugo S.,Autonomous University of Nuevo León | Pena Y.,Autonomous University of Nuevo León | Calixto-Rodriguez M.,National Autonomous University of Mexico | Lopez-Mata C.,Technological Institute of Chetumal | And 3 more authors.
Applied Surface Science | Year: 2012

AgInS2 thin films were obtained by the annealing of chemical bath deposited In2S3-Ag2S layers at 400 °C in N2 for 1 h. According to the XRD and EDX results the chalcopyrite structure of AgInS2 has been obtained. These films have an optical band gap, Eg, of 1.86 eV and an electrical conductivity value of 1.2 × 10-3 (Ω cm)-1. © 2012 Elsevier B.V.

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