Search

El pabellón del Reino de Murcia en la Exposición Iberoamericana de Sevilla representó de manera conjunta a las provincias de Murcia y Albacete, ligadas históricamente. Las propuestas para el edificio, que sirvió de espacio expositivo, se centraron en mostrar un diseño arquitectónico que reuniera aspectos constructivos, decorativos y culturales propios del pasado histórico de la zona. En este trabajo se documenta la participación e historia del proyecto murciano-albacetense y se analizan los diseños realizados para el pabellón hasta la definitiva construcción del edificio.

Urban Heat Islands are a major environmental and public health concern, causing temperature increase in urban areas. This study used satellite imagery and machine learning to analyze the spatial and temporal patterns of land surface temperature distribution in the Metropolitan Area of Merida (MAM), Mexico, from 2001 to 2021. The results show that land surface temperature has increased in the MAM over the study period, while the urban footprint has expanded. The study also found a high correlation (r> 0.8) between changes in land surface temperature and land cover classes (urbanization/deforestation). If the current urbanization trend continues, the difference between the land surface temperature of the MAM and its surroundings is expected to reach 3.12 °C ± 1.11 °C by the year 2030. Hence, the findings of this study suggest that the Urban Heat Island effect is a growing problem in the MAM and highlight the importance of satellite imagery and machine learning for monitoring and developing mitigation strategies.

This research proposes implementing a system to recognize the static signs of the Mexican Sign Language (MSL) dactylological alphabet using the MediaPipe frame and Convolutional Neural Network (CNN) models to correctly interpret the letters that represent the manual signals coming from a camera. The development of these types of studies allows the implementation of technological advances in artificial intelligence and computer vision in teaching Mexican Sign Language (MSL). The best CNN model achieved an accuracy of 83.63% over the sets of 336 test images. In addition, considering samples of each letter, the following results are obtained: an accuracy of 84.57%, a sensitivity of 83.33%, and a specificity of 99.17%. The advantage of this system is that it could be implemented on low-consumption equipment, carrying out the classification in real-time, contributing to the accessibility of its use.

Background. As body weight (BW) is rarely determined on fasted animals in most production systems, the need to develop accurate mathematical models for adjusting BW has been identified. Objective. To evaluate models for estimating shrunk body weight (SBW) and empty body weight (EBW) in Black Belly growing ewe lambs raised in tropical conditions. Methodology. Data of sixty Black Belly ewe lambs, between four to eight months of age with a mean BW of 26.55± 3.92 kg (± SD) were used. The SBW was estimated based on the BW without fasting (fed) and the EBW based on SBW through three models: 1. Linear; 2.-Linear without intercept and 3.- Exponential. The predictive capacity of the models was evaluated by cross-validation. Results. The correlation coefficients between BW and SBW and SB and EBW were high (r = 0.94;

This paper presents an intelligent system for the dynamic estimation of sheep body weight (BW). The methodology used to estimate body weight is based on measuring seven biometric parameters: height at withers, rump height, body length, body diagonal length, total body length, semicircumference of the abdomen, and semicircumference of the girth. A biometric parameter acquisition system was developed using a Kinect as a sensor. The results were contrasted with measurements obtained manually with a flexometer. The comparison gives an average root mean square error (RMSE) of 9.91 and a mean R2 of 0.81. Subsequently, the parameters were used as input in a back-propagation artificial neural network. Performance tests were performed with different combinations to make the best choice of architecture. In this way, an intelligent body weight estimation system was obtained from biometric parameters, with a 5.8% RMSE in the weight estimations for the best architecture. This approach represents an innovative, feasible, and economical alternative to contribute to decision-making in livestock production systems.

Weight prediction in live animals remains challenging. Several studies have been carried out trying to predict the body weight in livestock through morphometric measurements, the Schaeffer's model is one of them. However, the fit of those studies in small ruminants is not well covered. Therefore, a novel model to predict the weight of Pelibuey sheep through morphometric measurements and the Gray Wolf Optimizer algorithm is presented. The model involves calculating the volume of the specimen through a truncated cone and leaving density as an estimation parameter of the algorithm. Also, two alternative models were made where the original Schaeffer's model was optimized. The modified models from the original Schaeffer's formula showed improvements up to 22.61% in R-squared and decreases up to 33.48% in RMSE. However, the truncated cone model had the best estimates, with an RMSE of 2.57, R-squared of 89.02%, and the lowest AIC. This represented a 25.13% improvement in R-squared and a 38.31% reduction in the RMSE. The model is expected to improve its efficiency if the cattle sample is larger, and it is also intended to be implemented in animals of other proportions.

This study aims to use advanced machine learning techniques supported by Principal Component Analysis (PCA) to estimate body weight (BW) in buffalos raised in southeastern Mexico and compare their performance. The first stage of the current study consists of body measurements and the process of determining the most informative variables using PCA, a dimension reduction method. This process reduces the data size by eliminating the complex structure of the model and provides a faster and more effective learning process. As a second stage, two separate prediction models were developed with Gradient Boosting and Random Forest algorithms, using the principal components obtained from the data set reduced by PCA. The performances of both models were compared using R2, RMSE and MAE metrics, and showed that the Gradient Boosting model achieved a better prediction performance with a higher R2 value and lower error rates than the Random Forest model. In conclusion, PCA-supported modeling applications can provide more reliable results, and the Gradient Boosting algorithm is superior to Random Forest in this context. The current study demonstrates the potential use of machine learning approaches in estimating body weight in water buffalos, and will support sustainable animal husbandry by contributing to decision making processes in the field of animal science.

Background: Assessment of animal growth based on live weight (LW) in traditional sheep production systems is limited by the high cost of purchase and maintenance of livestock scales. Objective: To develop and evaluate equations for LW prediction using heart girth (HG) in growing Pelibuey sheep. Methods: A dataset (n=415) of clinically healthy male Pelibuey sheep from two months to one year of age, with an average LW of 25.96 ± 10.25 kg and HG of 68.31 ± 10.53 cm, were used. Three equations were evaluated: LW (kg) = −37.70 + 0.93 × HG (Eq. 1); LW (kg) = −1.74 + 0.19 × HG + 0.008 × HG2 (Eq. 2); and LW (kg) = 0.003 × HG2.68 (Eq. 3). Results: The correlation coefficient between LW and HG was r = 0.94 (p0.05). On the other hand, for Eqs. 1 and 3 the intercept was different from zero and the slope was different from one (p

Background. The empty body weight (EBW) represents exactly the animal mass and is used as a base to calculate most of the nutrient requirements in most feeding systems. Objective. To evaluate models for estimating EBW in growing hair sheep in a feedlot system under tropical conditions. Methodology. One hundred fifteen male growing hair sheep lambs (Pelibuey, Black Belly, and Katahdin) between four to ten months of age with a mean shrunk body weight (SBW) of 34.50 ± 7.40 kg (± SD) were used. The relationship between SBW and EBW was assessed by means of three models: Eq. 1. Linear with intercept; Eq. 2.- Linear without intercept and Eq. 3.- Allometric. The predictive ability of models was evaluated by cross-validation. Results. The correlation coefficient among SBW and EBW was high (r = 0.98). The regression equations had high determination coefficients (r2) of 0.97. Based on the evaluations Eq.1 had the performance compared with other models. The following final model was fitted to estimate the EBW as a function of SBW of growing castrated male hair sheep: EBW (kg): -2.39 (± 0.53***) + 0.95(± 0.02***) × SBW (kg). Implications. These results contribute to the development of mathematical models for more accurate weight adjustments in growing hair sheep in a feedlot system under tropical conditions. Conclusion. The equation developed and evaluated in the present study revealed that the linear relationship between SBW and EBW can be used to predict EBW in hair sheep, for that the use of this model can be safely applied to male hair sheep. In addition, it was found that the relation BW/EBW was on average 1.18 for males.

Background. In terms of animal management, the measurement of body weight (BW) is important in the design of nutrition and health programs. Objective. The objective of the present study was to evaluate the relationship between body volume (BV) and BW in Pelibuey ewe lambs and ewes. Methodology. For the model development, the BW and body volume (BV) were recorded in 406 Pelibuey ewe lambs and ewes ranging from two months to one years in age. All animals were clinically healthy, with a BW = 37.62 ± 10.63 kg. The BV was calculated using the heart girt (HG) and the body length (BL). BV was calculated according to the mathematical formulas for calculating the volume of a cylinder, considering biometric measurements in the calculation. The relationship between BV and BW was assessed by linear (Eq. 1), quadratic (Eq. 2) and allometric equation (Eq. 3). The goodness of fit of the regression models was assessed by the Akaike information criterion (AIC), Bayesian information criterion (BIC), coefficient of determination (R2), mean square error (MSE) and root mean square error (RMSE). Results. The correlation coefficient (r) between BW and BV was 0.89 (P < 0.001). The quadratic model had the higher value of coefficient of determination (R2= 0.81, and the lower MSE (4.17), RMSE (2.04), AIC (1163.64) and BIC (1175.66) values. The predictive ability of the three live weight prediction models was evaluated using k-folds validation (k = 10). Implications. The quadratic model had the higher coefficient of determination and lowest values were found for the mean square error (MSE) and mean absolute error (MAE). This model is practical and predicts with high accuracy the BW of the animals. Conclusion. Based on the evaluation approaches used in the present study and the close relationship between BW and BV in Pelibuey ewe lambs and adult ewes, the quadratic model was the mathematical model that had the best performance according to the goodness-of-fit evaluation.

The Body Weight (BW) of sheep is an important indicator for producers. Genetic management, nutrition, and health activities can benefit from weight monitoring. This article presents a polynomial model with an adjustable degree for estimating the weight of sheep from the biometric parameters of the animal. Computer vision tools were used to measure these parameters, obtaining a margin of error of less than 5%. A polynomial model is proposed after the parameters were obtained, where a coefficient and an unknown exponent go with each biometric variable. Two metaheuristic algorithms determine the values of these constants. The first is the most extended algorithm, the Genetic Algorithm (GA). Subsequently, the Cuckoo Search Algorithm (CSA) has a similar performance to the GA, which indicates that the value obtained by the GA is not a local optimum due to the poor parameter selection in the GA. The results show a Root-Mean-Squared Error (RMSE) of 7.68% for the GA and an RMSE of 7.55% for the CSA, proving the feasibility of the mathematical model for estimating the weight from biometric parameters. The proposed mathematical model, as well as the estimation of the biometric parameters can be easily adapted to an embedded microsystem.

*El autor desea extender un agradecimiento a la Dirección General de Asuntos del Personal Académico de la UNAM, por su apoyo al proceso de investigación mediante el Proyecto IN400920 PAPIIT: Imágenes y poder en América Latina. La Revolución cubana como modelo de construcción épica. El objetivo de este texto es realizar el acercamiento a una captura fotográfica que se hizo a Fidel Castro el 8 de enero de 1959 en el Cuartel Columbia. Ese día, el dirigente revolucionario llegó a La Habana, después de que había transcurrido una semana de la salida del dictador Fulgencio Batista (el 1° de enero del mismo año). Luego de bajar de la afamada Sierra Maestra el líder guerrillero inició una travesía terrestre a lo largo de toda la isla, desde Santiago de Cuba hasta la capital. Se remarca la fecha de ese 8 de enero, dado que el 14 de septiembre del mismo año también se desarrolló otro destacado acto. En esta segunda fecha, Castro formalizaría la conversión del edificio militar en centro educativo, que sería denominado como Ciudad Escolar Libertad. Además, se habla puntualmente del Cuartel Columbia, dado que ese mismo día también se capturaron muchas otras fotografías sobresalientes, como sucedió durante el discurso que emitió el propio Fidel en el Palacio Presidencial. Como premisa hipotética se sostiene que en dicha fotografía se encierra un potencial histórico y visual que poco se ha atendido, y que tal circunstancia de descuido impide ampliar el conocimiento histórico que algunos vestigios iconográficos ofrecen –como el de esa imagen que en este texto se analizará detenidamente– para una mejor comprensión de la realidad cubana, y también latinoamericana.

The objective of this study was to determine post-mortem measurements for predicting carcass traits in growing rabbits. A total of 50 clinically healthy New Zealand White × Californian male rabbits with a body weight (BW) of 1351 ± 347 g between 60 to 80 days of age were used. Body weight was recorded 12 h before slaughtering. Data recorded at slaughtering included carcass weights (HCW). After cooling at 4 °C for 24 h, carcasses were weighed (CCW) and then were carefully split longitudinally with a band saw to obtain left and right halves. In the right half carcass, the following measurements were recorded using a tape measure: dorsal length (DL), thoracic depth (TD), thigh length (TL), carcass length (CL), lumbar circumference (LC). The compactness index (CCI) was calculated as the CCW divided by the CL. Thereafter, the right half carcass was weighed and manually deboned to record weights of muscle (TCM), and bone (TCB). The CCI explained of 93% of variation for TCM (R2 = 0.93 and a CV = 9.30%). In addition, the DL was the best predictor (p < 0.001) for TCB (R2 = 0.60 and a CV = 18.9%). Our results indicated that the use of carcass measurements could accurately and precisely (R2 = ≥ 0.60 and ≤0.95) be used as alternatives to predict the carcass tissues composition in growing rabbits.

El objetivo de este texto es analizar algunos vestigios visuales, tales como lo son las tarjetas postales vinculadas al tema de las plantaciones circuncaribeñas del banano, atendiendo de manera particular el caso costarricense. Luego de realizar una lectura iconológica, presentar el tipo de discurso que de ellas emana, sosteniendo como tesis que, a través de las imágenes en las que se destaca el adelanto tecnológico mediante la iconografía de barcos y ferrocarriles, se construye un imaginario de prosperidad y bonanza, que sería la propuesta/el objetivo de las compañías bananeras, instaladas en una extensa región bañada por el Mar Caribe, entre finales del siglo XIX y principios del siglo XX.

Este libro, anunciado como una biografía evidentemente de uno de sus parientes, como se aprecia en el mismo apellido del personaje central y del autor, es decir, Price, se convierte a través de sus páginas en una escritura que poco a poco, paso a paso, va atrapando al lector interesado en la historia del Circuncaribe, aquella región que, bañada por el Mar Caribe en la parte insular y continental, comparte entre sí una trayectoria histórica y político-social de siglos.

Martín Casillas desarrolló buena parte de su trayectoria artística en Nueva España. Sin embargo, su obra se ha asociado casi en exclusividad a su intervención como maestro mayor de la catedral de Guadalajara a partir de finales del siglo XVI. El presente artículo destaca nuevas noticias que amplían su producción arquitectónica, lo que ha permitido realizar una serie de apreciaciones.

Nationalism seems a persistent ideology in academia as much as in politics; despite the fact that it has been shown that nationalism is deeply unjust for minorities. A case for national identity is often invoked to supplement liberalism regarding the inner difficulties that liberal theories have to explain their membership, assure stability and produce endorsement. So it seems that national identity may also be required for justice. While this controversy continues, I argue that a different approach is available. We can define a conception of legitimacy independently from a conception of justice, and then ask what legitimacy requires from our national allegiances. If everything goes well, much of the controversy from justice disappears as we find that the case for cultural nationalism may be illegitimate for liberal democracies.

Many conservatives endorse a defence of closed borders grounded in basic liberal rights such as the basic right of association. Some conservatives also endorse libertarian principles of legitimacy. It is not clear though that this sort of defence of closed borders is somehow coherent with these libertarian ideals. I argue that conservative libertarians of this kind must reject this defence of closed borders because either it collapses into a form of statism incoherent with libertarian principles of legitimacy, or into an ideal precept without appeal regarding reality in the here and now that could only be applied to changing the very nature of the societies we know. As a result, at least conservative libertarians need to find a different source of justification for closed borders.

The debate about justice in immigration seems somehow stagnated given that it seems justice requires both further exclusion and more porous borders. In the face of this, I propose to take a step back and to realize that the general problem of borders—to determine what kind of borders liberal democracies ought to have—gives rise to two particular problems: first, to justify exclusive control over the administration of borders (the problem of legitimacy of borders) and, second, to specify how this control ought to be exercised (the problem of justice of borders). The literature has explored the second but ignored the first. Therefore, I propose a different approach to the ethics of immigration by focusing on concerns of legitimacy in a three-step framework: first, identifying the kind of authority or power that immigration controls exercise; second, redefining borders as international and domestic institutions that issue that kind of power; and finally, considering supranational institutions that redistribute the right to exclude among legitimate borders.

Dentro del estudio de la producción escrita sobre la guerra de independencia en Cuba, ya sea de la efectuada entre 1868 y 1878, o la del período 1895-1898, existen dos grandes vertientes. Por un lado está la interpretación que los españoles dieron al fenómeno y, por otra parte, aquella que refleja el punto de vista hispanoamericano sobre la lucha independentista. Se trata de visiones encontradas que intentaron imponerse como las poseedoras de la razón, siempre con la finalidad de apoyar aquellos proyectos políticos con los cuales los autores se sintieron identificados. Ubicado en el panorama formado por las obras representativas del grupo hispanoamericano, encontré el caso de una obra que me llamó la atención por la intencionalidad que marcaba desde su título mismo. Me refiero a Cuba. Justificación de su guerra de independencia. Su autor, Rafael María Merchán, es uno de los intelectuales cubanos más importantes de la segunda mitad del Siglo XIX, lo cual es un elemento importante para incorporarlo dentro de un trabajo cuyo objetivo es explicar la influencia de la independencia de Cuba en los intelectuales españoles e hispanoamericanos. La obra mencionada me resultó atractiva particularmente porque no se trataba de un texto que escondiera la finalidad política de su trabajo intelectual. Además, durante la búsqueda de datos sobre el escritor, me encontré que junto a su trayectoria como intelectual había una destacada trayectoria como político, sobresaliendo allí su vínculo con la lucha independentista de 1868. El conjunto de estos factores me motivó a elaborar esta presentación dedicada a Merchán y su historiografía independentista.

During the first half of the twentieth century, the United Fruit Company (UFCo.), a multinational corporation founded in 1899 in order to exploit the agricultural wealth of the Caribbean, was responsible for considerable amounts of propaganda, newspaper ads, postcards, books, etc. These were linked to the commercial and tourism activities of the United States in Caribbean countries. The goal of UFCo was to influence the imperial vision of the Central American and Caribbean area from an iconographic point of view. In that world of images, postcards were very important as artifacts in which a visual discourse imposed an ideal of social imagination that was stimulated by the banana company. One of the artists who participated in this process was Gomes Casseres, a photographer who left his name printed on several postcards that have been found and have been subjected to iconological examination. This paper will analyze such cultural artifacts and will show that these images responded to the idea of Caribbean geography that "mamita yunai" constructed and which imposed itself from afar as the "reality" of Costa Rica.