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Geographical distribution of forest species is closely regulated by environmental conditions, particularly temperature and precipitation. Climate change predicted by general circulation models is expected to modify the distribution of many species' distribution, especially those adapted to extreme environmental conditions, leading to large-scale migrations or local extinctions. The aim of this research was to determine the potential impact of climatic change on Pinus hartwegii geographic distribution and the niche breadth of its populations. Ecological niche models were used by generated with four different algorithms based on 19 bioclimatic variables in addition to altitude. Climatic niche breadth was delimited by the dispersion of species occurrence records within the intervals of the bioclimatic variables. We modelled future distribution based on three general circulation models, MIROC-ESM-CHEM, CCSM4 and HadGEM2-ES, using two representative concentration pathways (RCP) 2.6 and 8.5, for two-time horizons 2050 and 2070. Niche breadth analysis showed narrow ranges of suitability, indicating a strong relationship between the presence of P. hartwegii with the temperature of the warmest quarter and precipitation of the coldest quarter. In addition, the suitability area of P. hartwegii is predicted to be reduced up to 70% by 2070; the populations of the extreme northern and southern latitudes will be reduced in greater proportion than those of central Mexico. This suggest that environmental suitability area of P. hartwegii are reduced by the effect of the increase in environmental temperature. Therefore, it is necessary to monitor extreme populations of this species in the long term in order to establish efficient conservation strategies and well adaptive management facing climate change.

Introducción: La complejidad del ecotono del límite superior del bosque de Pinus hartwegii puede funcionar como una barrera para la migración altitudinal. Objetivos: La estructura del bosque de P. hartwegii se caracterizó a través del ecotono de su límite superior en el Nevado de Toluca; además, se determinaron los posibles cambios en los límites altitudinales en los últimos 25 años. Materiales y métodos: Se determinaron la densidad arbórea, altura y diámetro normal de cada árbol, y la regeneración natural del bosque. Los límites altitudinales se determinaron mediante el método de la ventana móvil en imágenes de satélite de 1989 y 2014. Resultados y discusión: La densidad del arbolado se redujo entre 8 y 70 % en el gradiente altitudinal. Los límites altitudinales (3,980-4,130 m) no presentaron diferencias significativas ( P = 0.07) entre los años evaluados. El ecotono es de forma difusa, regulado por limitaciones al crecimiento. Esto implica que el bosque modificará su distribución altitudinal en función de los cambios ambientales, de acuerdo con su amplitud ecológica y la rapidez con que puedan establecerse nuevos individuos a mayores altitudes. Conclusión: Es importante establecer monitoreos, a largo plazo, para saber si la especie es realmente capaz de migrar altitudinalmente como resultado del incremento de temperatura ambiental.

Las sociedades progresan: la actual, en un mundo que comandan la globalización y la informática, es una sociedad postmoderna. En ella, se han modificado las formas de transmitir y relacionar socialmente la cultura; se han desarrollado nuevos seres humanos, individuos postmodernos con características muy particulares: ellos son nuestros alumnos. ¿Cómo optimizamos la tríada del aprendizaje (alumno-docente-conocimientos)? No basta saber los contenidos y ser un especialista en la materia; es indispensable ser conscientes del entorno actual para analizar y comprender las características de nuestros alumnos, también denominados “hijos de la globalización” o “nativos digitales”. Solo así conoceremos, asimismo, nuestra propia realidad como individuos y docentes. El presente ensayo procura analizar las características de nuestros alumnos y reflexionar sobre nuestro papel como docentes en un entorno complejo y cambiante.

Introduction: Endometrial cancer (EC) is the second most common gynecologic malignancy worldwide in the peri and postmenopausal period. Most often for the endometrioid variety. In early clinical stages long-term survival is greater than 80%, while in advanced stages it is less than 50%. In our country there is not a standard management between institutions. GICOM collaborative group under the auspice of different institutions have made the following consensus in order to make recommendations for the management of patients with this type of neoplasm., Material and Methods: The following recommendations were made by independent professionals in the field of Gynecologic Oncology, questions and statements were based on a comprehensive and systematic review of literature. It took place in the context of a meeting of four days in which a debate was held. These statements are the conclusions reached by agreement of the participant members., Results: Screening should be performed women at high risk (diabetics, family history of inherited colon cancer, Lynch S. type II). Endometrial thickness in postmenopausal patients is best evaluated by transvaginal US, a thickness greater than or equal to 5 mm must be evaluated. Women taking tamoxifen should be monitored using this method. Abnormal bleeding in the usual main symptom, all post menopausal women with vaginal bleeding should be evaluated. Diagnosis is made by histerescopy-guided biopsy. Magnetic resonance is the best image method as preoperative evaluation. Frozen section evaluates histologic grade, myometrial invasion, cervical and adnexal involvement. Total abdominal hysterectomy, bilateral salpingo oophorectomy, pelvic and para-aortic lymphadenectomy should be performed except in endometrial histology grades 1 and 2, less than 50% invasion of the myometrium without evidence of disease out of the uterus. Omentectomy should be done in histologies other than endometriod. Surgery should be always performed by a Gynecologic Oncologist or Surgical Oncologist, laparoscopy is an alternative, especially in patients with hypertension and diabetes for being less morbid. Adjuvant treatment after surgery includes radiation therapy to the pelvis, brachytherapy, and chemotherapy. Patients with Stages III and IV should have surgery with intention to achieve optimal cytoreduction because of the impact on survival (51 m vs. 14 m), the treatment of recurrence can be with surgery depending on the pattern of relapse, systemic chemotherapy or hormonal therapy. Follow-up of patients is basically clinical in a regular basis., Conclusions: Screening programme is only for high risk patients. Multidisciplinary treatment impacts on survival and local control of the disease, including surgery, radiation therapy and chemotherapy, hormonal treatment is reserved to selected cases of recurrence. This is the first attempt of a Mexican Collaborative Group in Gynecology to give recommendations is a special type of neoplasm.