Date palm pollen (DPP) plays a very important role in the fertilization process, since its viability and the pollination method influence on the quality, development, and yield of the fruit. In the present study, a broad review of its main characteristics, consumption, and DPP production are presented, as well as a description of its extraction methods and viability tests. The evolution of the pollination methods used in the date palm is also presented, from its natural pollination to the use of specialized mechanical and electrical devices, as well as the use of dry DPP and the current trend towards the use of DPP in liquid suspension. Likewise, the efficiency of the methods of natural pollination (wind); traditional (strands placement); dusting hand; dusting with manual, mechanical, or electric pollinator; and liquid pollination were evaluated from the fruit set percentage (FSP). Finally, starting from a scientometric analysis, the pollination methods were widely discussed, concluding that the dusting spraying of pollen suspension with liquid DPP is the pollination method that commonly presents the highest FSP, followed by dusting dry DPP with a motorized pollinator.

Solar collector technologies operate with better performance when the Sun beam direction is normal to the capturing surface, and for that to happen despite the relative movement of the Sun, solar tracking systems are used, therefore, there are rules and standards that need minimum accuracy for these tracking systems to be used in solar collectors’ evaluation. Obtaining accuracy is not an easy job, hence in this document the design, construction and characterization of a sensor based on a visual system that finds the relative azimuth error and height of the solar surface of interest, is presented. With these characteristics, the sensor can be used as a reference in control systems and their evaluation. The proposed sensor is based on a microcontroller with a real-time clock, inertial measurement sensors, geolocation and a vision sensor, that obtains the angle of incidence from the sunrays’ direction as well as the tilt and sensor position. The sensor’s characterization proved how a measurement of a focus error or a Sun position can be made, with an accuracy of 0.0426° and an uncertainty of 0.986%, which can be modified to reach an accuracy under 0.01°. The validation of this sensor was determined showing the focus error on one of the best commercial solar tracking systems, a Kipp & Zonen SOLYS 2. To conclude, the solar tracking sensor based on a vision system meets the Sun detection requirements and components that meet the accuracy conditions to be used in solar tracking systems and their evaluation or, as a tracking and orientation tool, on photovoltaic installations and solar collectors.

En la actualidad, las escuelas de niveles básicos, así como las universidades, tienen problemas para motivar a los estudiantes a aprender matemáticas.Con la intención de combatir el desinterés de los estudiantes por el aprendizaje de las matemáticas dentro de los primeros semestres de educación superior, se creó una metodología llamada Adventure School. Esta metodología emplea actividades lúdicas basadas en el sistema de juegos de rol y hace atractivo el proceso de aprendizaje hacia las matemáticas; además, fomenta la motivación, participación y creatividad estudiantil.En la metodología de Adventure School los estudiantes escogen una “profesión” y forman una especie de fraternidad llamada “clan” que les da un beneficio durante el curso académico. Posteriormente los estudiantes trabajan en equipo resolviendo situaciones ficticias, establecidas por el profesor, donde se involucran ciertos temas del área de matemáticas. Conforme los estudiantes avanzan en la resolución de las situaciones ficticias, los estudiantes obtienen “puntos de experiencia” que les sirven para incrementar el beneficio de su profesión (aplicación de sistema de recompensas basado en la teoría del juego) hasta que llegan al nivel legendario, y entonces, pueden anexar otra profesión a su personaje. Desde hace más de cinco años se ha implementado esta metodología, obteniendo una respuesta positiva por parte de los estudiantes, logrando incrementar la participación en equipos y la socialización entre los estudiantes.La metodología de Adventure School está diseñada para trabajar en al área de matemáticas, pero con algunos ajustes, puede ser adaptada con facilidad a cualquier otra área de conocimiento.

Self-powered photodetectors (SPDs) have great application potential in next-generation instruments that operate wirelessly and independently. Hence, there is a strong market demand for more efficient, easier, cheaper, and faster SPDs fabrication methods and tools. Specially, spray pyrolysis (SS) is an extensively used technique because of its simplicity, cost-effectiveness, and high deposition rate. Furthermore, in a SS system, parameters such as the chamber temperature, air pressure, substrate temperature, and nozzle-substrate distance must be precisely selected since they determine the deposited film quality. Otherwise, pressurized air blast spraying is a standard atomization method implemented in economical and multi-use micro airbrush guns that can be used in conjunction with a substrate heater to complete the SS process. In this study, a fabrication procedure, complemented with a micro airbrush gun as an easy, inexpensive, and efficient tool for film deposition was developed and implemented to obtain a single and a parallel connection of four SPDs based on cadmium chalcogenides (CC). A comprehensive analysis of the optical and electrical properties of the obtained devices confirms the functionality of the implemented fabrication procedure. All fabricated SPDs devices show responsivity and specific detectivity in the visible spectrum demonstrating their capability for self-powered photodetection applications.

The dependence of photon absorption by a low-dimensional cadmium-sulfide/cadmium-telluride (CdS/CdTe) heterostructured absorber on the thickness and number of CdTe active layers is investigated. The equation for the photon absorption coefficient ($α$) used is based on the partial momentum $k$-selection approach. Theoretical results show that absorption greater than $4×104cm−1$ is obtained when the thickness of the active layer reaches 50 Å. Similarly, with each additional CdTe active layer in the heterostructured absorber, a relative increase of $0.5×104cm−1$ in photon absorption is achieved. The relation between photoelectric quantum efficiency and photon absorption is determined by the number and thickness of the CdTe active layers in the heterostructured absorber. A quantum efficiency greater than 0.9 is obtained using 15 active layers with a thickness of 50 Å.

Type 2 diabetes (T2D) is a chronic systemic disease with a complex etiology, characterized by insulin resistance and mitochondrial dysfunction in various cell tissues. To explore this relationship, we conducted a secondary analysis of complete mtDNA sequences from 1261 T2D patients and 1105 control individuals. Our findings revealed significant associations between certain single-nucleotide polymorphisms (SNPs) and T2D. Notably, the variants m.1438A>G (rs2001030) (controls: 32 [27.6%], T2D: 84 [72.4%]; OR: 2.46; 95%CI: 1.64–3.78; p < 0.001), m.14766C>T (rs193302980) (controls: 498 [36.9%], T2D: 853 [63.1%]; OR: 2.57, 95%CI: 2.18–3.04, p < 0.001), and m.16519T>C (rs3937033) (controls: 363 [43.4%], T2D: 474 [56.6%]; OR: 1.24, 95%CI: 1.05–1.47, p = 0.012) were significantly associated with the likelihood of developing diabetes. The variant m.16189T>C (rs28693675), which has been previously documented in several studies across diverse populations, showed no association with T2D in our analysis (controls: 148 [13.39] T2D: 171 [13.56%]; OR: 1.03; 95%CI: 0.815–1.31; p = 0.83). These results provide evidence suggesting a link between specific mtDNA polymorphisms and T2D, possibly related to association rules, topological patterns, and three-dimensional conformations associated with regions where changes occur, rather than specific point mutations in the sequence.