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Copyright of BIOAGRO is the property of Revista BIOAGRO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this work was to make a proposal for potential land use and the projection of climate change scenarios in the Papaloapan basin, using the multi-criteria and multi-objective analysis technique to generate potential capabilities in the basin. From the greatest aptitude, the scenarios were generated using the methodology for Maximum Entropy. The hydrological region was delimited through cartographic material and climatic information was obtained from meteorological stations, geographic information and databases were collected from official secondary sources, the information was processed in the ArcGIS version 10.2.2 program, to obtain the geodatabases and geospatial matrices that served as cartographic input for the multicriteria analysis. Based on the geospatial matrices and vector data, raster data were generated, which were used in the modeling with geo-statistical algorithms and potential zones were identified from a structured language. The result of the modeling regarding the suitability of the soil generated two classes with six levels of suitability: land for basic crops and for the cultivation of species of industrial importance and two climate change scenarios, current and future. [ABSTRACT FROM AUTHOR]

Prospectivity maps are based on probability models of occurrence of mineral deposits. It is the basis for the metallogenic prognosis and the delimitation of perspective areas. Different geological surveys have covered the northeastern region of Mexico, mining exploration works, and regional metallogenic studies and more than 160 deposits and manifestations of fluorite are currently reported. However, the methods that allow the manipulation, analysis and integration of the exploration guides used in the predictive cartography of mining potential have not been used. In this context, there is a need to start predictive mapping work in Mexico, which helps to minimize the costs of mineral exploration by optimizing areas potentially favourable to the occurrence of mineral deposits and discarding those areas without economic interest. The geological, structural, geochemical and geophysical information available is adequate to the application of prospectivity mapping supported by geographic information systems and based on the structuring of the primary data, the weighted overlap and the integration and analysis of the data through Boolean logic and maximum entropy models. Results indicate that the mineral potential mapping offers a good predictor because the areas with high prospectivity are correctly delimited as the most favourable for the occurrence of fluorite deposits. The structural density is the parameter that most influences with 28.8% of contribution to the mineral potentiality model. [ABSTRACT FROM AUTHOR]

The high biodiversity along with a great variety of ecosystems turn Andes Mountain one of the regions of greater environmental diversity of the world, where are the most extreme ranges of types of landscapes, climate and forest formations of the Earth, an area suitable for studying the possible effects of climate change on the spatial distribution of forest formations. For this it is essential to understand the effects of climate change in the area, where climate observations indicate different climate scenarios in the future, for a current time period and for the period 2040-2069, with variations in temperatures and precipitation. The distribution of forests through predictive modelling is analyzed using MaxEnt's maximum entropy method. The results indicate that most of the forest formations in the Andean forests analysed are expected to face significant problems in the near future, as a result of the loss of climate suitability in the current area of distribution and the geographic change of potentially suitable areas in the future as reflected in the results. [ABSTRACT FROM AUTHOR]

Copyright of Avances is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wild specimens of Vanilla planifolia represent a vital part of this resource primary gene pool, and some plants have only been reported in Oaxaca, Mexico. For this reason, we studied its geographical distribution within the state, to locate and describe the ecological characteristics of the areas where they have been found, in order to identify potential areas of establishment. The method comprised four stages: 1) the creation of a database with herbarium records, 2) the construction of the potential distribution based on historical herbarium records for the species, using the model of maximum entropy (MaxEnt) and 22 bioclimatic variables as predictors; 3) an in situ systematic search of individuals, based on herbarium records and areas of potential distribution in 24 municipalities, to determine the habitat current situation and distribution; 4) the description of the environmental factors of potential ecological niches generated by MaxEnt. A review of herbarium collections revealed a total of 18 records of V. planifolia between 1939 and 1998. The systematic search located 28 plants distributed in 12 sites in 95 364 Km2. The most important variables that determined the model of vanilla potential distribution were: precipitation in the rainy season (61.9 %), soil moisture regime (23.4 %) and precipitation during the four months of highest rainfall (8.1 %). The species potential habitat was found to be distributed in four zones: wet tropics of the Gulf of Mexico, humid temperate, humid tropical, and humid temperate in the Pacific. Precipitation oscillated within the annual ranges of 2 500 to 4 000 mm, with summer rains, and winter precipitation as 5 to 10 % of the total. The moisture regime and predominating climate were udic type I (330 to 365 days of moisture) and hot humid (Am/A(C) m). The plants were located at altitudes of 200 to 1 190 masl, on rough hillsides that generally make up the foothills of mountain systems, with altitudes of 1 300 to 2 500 masl. In natural conditions, distribution of the species is not limited to high evergreen forests, since it was also found in mountain mesophyll and tropical evergreen forests. The location of new specimens of V. planifolia in its wild condition reduces the potential distribution area by 66 %. This area is fragmented into three geographically separated areas. Habitat reduction was due to the increased number of located plants that define the environmental conditions into a more accurate level. Conservation actions can thus be designed and implemented, focusing on more specific areas within the state of Oaxaca, Mexico. [ABSTRACT FROM AUTHOR]

The Cactaceae family is distinguished by its morphology and anatomy that allows it to withstand prolonged periods of drought and high solar radiation. For some of its species there is a lack of basic information regarding distribution, status and fundamental niche. This is the case of Coryphantha chihuahuensis, reported in the Chihuahua state in the Chihuahuan Desert region. The aim of this study was to determine the fundamental niche of Coryphantha chihuahuensis in the state of Chihuahua, displaying possible and suitable areas in which the species could develop. During fieldwork 20 georeferenced sites with species occurrence were recorded. The species fundamental niche was determined using three models with different combinations of variables (bioclimatic variables, altitude, soil, land use and vegetation). The algorithm used was MaxEnt (maximum entropy). The results indicate that the model with the lowest error was the model that contained all variables, with an effectiveness value of 99% and a standard deviation of 0.001. The model places the fundamental niche of the species in the center and south of the state, with a probability of occurrence of 70 to 100% at the center; while the lowest values were south-central and northeast of the state with the probability of presence of 30 to 50%. The obtained model used to determine the fundamental niche for C. Chihuahua is timely as it shows probable and appropriate areas for the species. This will help in the protection, conservation and recovery of the species. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is the second most prevalent neurodegenerative clinical condition after Alzheimer's disease and for the global health system it is essential to identify early signs; however, nowadays it is still a new field of study that needs further development. It has been shown that about 90% of Parkinson's disease patients also develop deficiencies in her voice, showing symptoms such as monotone speech, low-intensity tone, isolated breaks, inaccurate pronunciation of consonants and prosody problems. Although such problems are identified, only 3% to 4% are treated as a voice problem. In the field of research, time-frequency analysis has proven to be a powerful tool in the processing of acoustic signals, more specifically, the voice processing. With the aim of having clean representations of the spectrum to help with the removal of characteristics and mitigate other resulting problems when using estimated classical methods, it was decided to study the behavior of maximum entropy method, which is currently used in oceanography and astronomy in the study of voice signals. For these experiments, a database of patients with Parkinson's disease was used. Fifty records of pathological voices and the same amount of healthy voices were studied. Voiced and voiceless segments derived from the word "PA-TA-KA" produced by those patients were analyzed. Energies were estimated from both the Fourier transform and the maximum entropy method. In order to evaluate the performance of the classical methods and the method of maximum entropy, a K-nn classifier was used and success rates were found in around 60% taking into account the maximum entropy method in both syllables and phonemes. [ABSTRACT FROM AUTHOR]

Copyright of Agro Productividad is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Economía Aplicada is the property of Revista de Economia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The method of the Principle of Maximum Entropy (POME) applied to the estimation of parameters of the extreme value type I distribution, (EVI) is analyzed. The POME method has been compared with others of widespread use, like the methods of moments (MOM), maximum likelihood (ML) and probability weighted moments (PWM), with both real flood data and through distributional sampling experiments. The POME method was another good option for estimating the parameters of the EVI distribution, but not as good as those provided by the methods of PWM, ML and MOM. It was also detected that the POME method has a better performance when the sample size is bigger than 50 values of maximum annual floods. [ABSTRACT FROM AUTHOR]