Empresarios y gobierno en el desarrollo regional del estado de Zacatecas

Este trabajo analiza el desenvolvimiento del empresario en el estado de Zacatecas, México y los factores que han incidido en su desarrollo. Se pone particular atención en el papel del gobierno en cuanto a la orientación de sus esfuerzos como promotor e impulsor de la actividad empresarial partiendo de un enfoque evolucionista, se muestra que la pobre actividad empresarial en la entidad responde a un contexto económico deprimido, históricamente aunado a un mal diseño de la política pública de los gobiernos estatales, que se orienta a favorecer el crecimiento económico basado en la industrialización misma que se pretende lograr a partir de la atracción de inversión foránea. Los resultados del trabajo indican que el gobierno poco favorece el desarrollo de empresarios y la creación de empresas locales. El modelo económico que se impulsa, se sustenta en la creación de infraestructura para la rentabilización de la inversión privada y en donar terreno para loa construcción de la planta, capacitación de los trabajadores y apoyar con los costos de parte de la infraestructura de la planta. Se le apuesta al crecimiento a partir de inversión foránea, sin una propuesta explícita clara de una política para impulsar la creación de empresas y empresarios locales. Más bien se aprecia que se parte del supuesto que las empresas grandes generan mayor impacto que las pequeñas a través de la generación de empleos y de los indicadores macro de la entidad. En la práctica, el efecto de la política económica emprendida por el gobierno, lleva a la destrucción de las pequeñas de origen local

Support for real-time applications on mobile devices

RESUMEN: Los dispositivos móviles como teléfonos o tabletas inteligentes han experimentado en los últimos años mejoras muy significativas tanto a nivel de hardware como de software. En la actualidad esta clase de dispositivos ofrecen potentes sistemas operativos enfocados principalmente a las necesidades del gran público. Entre los distintos sistemas operativos disponibles el más extendido es Android. Sin embargo, a diferencia de lo que ha ocurrido con los sistemas embebidos tradicionales, no se han llevado a cabo grandes desarrollos que permitan usar sistemas como Android en entornos donde las aplicaciones utilizadas necesiten cumplir requisitos temporales. Por este motivo, en esta tesis se ha propuesto una solución portable que se aprovecha de las arquitecturas multinúcleo de los dispositivos móviles actuales para aislar núcleos del procesador, y así ejecutar en dichos núcleos aplicaciones de tiempo real con pocas interferencias que puedan afectar a su respuesta temporal. Además, en la solución presentada las aplicaciones de tiempo real pueden coexistir y compartir datos con otras aplicaciones del sistema sin requisitos temporales gracias a los protocolos de sincronización no bloqueantes desarrollados en esta tesis.ABSTRACT: In recent years, mobile devices such as smartphones or tablets have experienced very significant improvements, both in terms of hardware and software. Nowadays, this class of devices offers powerful operating systems mainly focused on the needs of the general public. Among the different operating systems available, Android is the most widespread. However, unlike what has happened with traditional embedded systems, no major developments have been made to allow the use of systems such as Android in environments where applications normally need to meet a series of timing requirements. For this reason, in this thesis a novel solution has been proposed that takes advantage of the multicore architectures of current mobile devices to isolate processor cores. By applying this solution, it is possible to run real-time applications on the isolated cores with little interference on their response times. Furthermore, in the solution presented, real-time applications can coexist and share data with other system applications without timing requirements thanks to the non-blocking synchronization protocols developed in this thesis

Non-Blocking Synchronization Between Real-Time and Non-Real-Time Applications

Real-time systems where applications with timing requirements coexist with applications without timing constraints are increasingly common. Furthermore, the processors used in desktops, smart phones or embedded devices are mostly multi-core, allowing the execution of applications in parallel. This article presents a set of non-blocking synchronization mechanisms to share data between real-time and non-real-time applications executing in different cores of a shared memory multi-core system. Four typical producer/consumer scenarios have been explored; a) shared data object with real-time reader, b) shared data object with real-time writer, c) shared queue with real-time writer, and d) shared queue with real-time reader. For these scenarios we have developed different non-blocking protocols where the execution of the real-time application is always prioritized over the execution of the non-real-time part. In this way, the real-time applications never have to repeat their operations and, consequently, their execution times are bounded. Furthermore, to reduce the overhead caused by the copies of the information used in the non-blocking algorithms, we have imposed the limitation of a single real-time reader or a single real-time writerinthealgorithmsdeveloped.Finally,we have evaluated the response times of the developed protocols on a multi-core device with the Android operating system.This work was supported in part by the Spanish Government and FEDER funds (AEI/FEDER, UE) under Grant TIN2017-86520-C3-3-R (PRECON-I4)

Continuous Positive Airway Pressure Treatment in Patients with Alzheimer's Disease: A Systematic Review

Background: Epidemiological studies have suggested a pathophysiological relationship between obstructive sleep apnea syndrome (OSAS) and Alzheimer's disease (AD). The aim of this study is to evaluate the treatment of obstructive sleep apnea with continuous positive airway pressure (CPAP) in AD and its relationship with neurocognitive function improvement. Methods: Systematic review conducted following PRISMA's statements. Relevant studies were searched in MEDLINE, PEDro, SCOPUS, PsycINFO, Web of Science, CINAHL and SportDicus. Original studies in which CPAP treatment was developel in AD patients have been included. Results: 5 studies, 3 RCTs (Randomized controlled trials) and 2 pilot studies. In all RCTs the CPAP intervention was six weeks; 3 weeks of therapeutic CPAP vs. 3 weeks placebo CPAP (pCPAP) followed by 3 weeks tCPAP in patients with AD and OSA. The two pilot studies conducted a follow-up in which the impact on cognitive impairment was measured. Conclusions: CPAP treatment in AD patients decreases excessive daytime sleepiness and improves sleep quality. There are indications that cognitive deterioration function measured with the Mini Mental Scale decreases or evolves to a lesser extent in Alzheimer's patients treated with CPAP. Caregivers observe stabilization in disease progression with integration of CPAP. More research is needed on the topic presented

Gas exchange and water relations of young apricot plants under drought conditions

Potted 1.5-year-old apricot plants (Prunus armeniaca L.), growing under polycarbonate glasshouse conditions with a cooling system, were subjected to two successive water stress/recovery periods until pre-dawn leaf water potential (Ypd) reached values between -2.0 and -2.5 MPa, during summer 1996. Control plants were irrigated daily to maintain the soil matric potential at c. -20 kPa. Water stress limited plant growth and induced a significant reduction in leaf area, caused by mature leaf abscission. The parallel behaviour of leaf turgor potential and epinasty in stressed plants indicated that these movements are turgor-dependent. Osmotic adjustments of 0.27 and 0.60 MPa were observed at the end of the first and second stress period, respectively. Relative apoplastic water content (RWCa) values were high, ranging from 27 to 42%, and were not affected by water stress. The rapid decrease in leaf conductance (gl) from the beginning of the stress periods, together with the delay in stomatal reopening after rewatering the plants, indicated that stomatal behaviour was not a simple passive response to water deficits. Net photosynthesis decreased only at the end of both stress periods and recovered quickly. These observations indicate that leaf productivity may be affected only slightly by short-term water stress. The results indicate that drought resistance in apricot is based mainly on avoidance mechanisms, such as stomatal control, epinasty and limitation of transpiration by reducing leaf area. However, some tolerance characteristics, including osmotic adjustment, high RWCa and low leaf osmotic potential at turgor loss point (Ytlp) values were observed.The authors are grateful to J. Soto-Montesinos, M.D. Velasco, M. García and E. Nicolás for their assistance. The study was supported by CICYT (AMB95- 0071) and Consejería de Medio Ambiente, Agricultura y Agua de Murcia grants to the authors

Los productores y la producción agrícola de temporal en la región Río Grande-Sombrerete Zacatecas

El trabajo trata sobre las causas de los problemas de la agricultura de temporal en la región Sombrerete-Río Grande, Zacatecas, manifiestas en cambios de las características de los agricultores y los procesos productivos de la región. Se sostiene que los cambios son resultado de la profundización de la crisis agrícola generada por la apertura comercial, la reducción del apoyo gubernamental y un pobre nivel productivo, derivado de las condiciones climáticas que limitan la incorporación tecnológica. La información utilizada en el trabajo proviene tanto del INEGI, como de entrevistas a productores de las comunidades en cuestión. El trabajo se organiza en apartados. El primero, una introducción, en el que se hace la presentación del trabajo; un segundo (El campesino y la agricultura en la apertura), en el que se presenta la teoría que enmarca el análisis empírico que se presenta posteriormente; un tercer apartado (Modelo económico, TLCAN y producción agrícola en México), en el que se refieren los efectos de la apertura y el modelo económico adoptado en México a partir de los años ochenta, en el sector agropecuario mexicano; un cuarto apartado, en el que se presenta a Zacatecas en su aspecto económico, ubicando el sector agropecuario como uno que pierde terreno en su aportación (proporcional) a la economía y al empleo; un quinto apartado (Estructura de la producción agrícola en Sombrerete y Río Grande) en el que se refiere a los hallazgos respecto de los cambios en la producción y en la forma en que los productores están haciendo frente a los efectos de la apertura y a la nueva política económica; y, finalmente un apartado de conclusiones

Lifting velocity predicts the maximum number of repetitions to failure with comparable accuracy during the Smith machine and free-weight prone bench pull exercises

This study compared the accuracy of the fastest mean velocity from set (MVfastest) to predict the maximum number of repetitions to failure (RTF) between 2 variants of prone bench pull (PBP) exercise (Smith machine and free-weight) and 3 methods (generalized, individualized multiplepoint, and individualized 2-point). Twenty-three resistance-trained males randomly performed 2 sessions during Smith machine PBP and 2 sessions during free-weight PBP in different weeks. The first weekly session determined the RTF-MVfastest relationships and subjects completed single sets of repetitions to failure against 60-70-80-90%1RM. The second weekly session explored the accuracy of RTFs prediction under fatigue conditions and subjects completed 2 sets of 65%1RM and 2 sets of 85%1RM with 2 min of rest. The MVfastest associated with RTFs from 1 to 15 were greater for Smith machine compared to free-weight PBP (F ≥ 42.9; P < 0.001) and for multiplepoint compared to 2-point method (F ≥ 4.6; P ≤ 0.043). The errors when predicting RTFs did not differ between methods and PBP variants, whereas all RTF-MVfastest relationships overestimated the RTF under fatigue conditions. These results suggest that RTF–MVfastest relationships present similar accuracy during Smith machine and free-weight PBP exercises and it should be constructed under similar training conditions.The Biomedicine Doctoral Studies of the University of Granada, SpainSpanish Ministry of University under a predoctoral grant (FPU19/01137)Spanish Ministry of Science and Innovation [PID2019- 110074GBI00/SRA/10.13039/501100011033)