University of Alcalá

About: University of Alcalá is a education organization based out in Alcalá de Henares, Spain. It is known for research contribution in the topics: Population & Receptor. The organization has 10795 authors who have published 20718 publications receiving 410089 citations. The organization is also known as: University of Alcala & University of Alcala de Henares.

The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project

Abstract: The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

Evidence for CO shock excitation in NGC 6240 from Herschel Spire spectroscopy

Abstract: We present Herschel SPIRE FTS spectroscopy of the nearby luminous infrared galaxy NGC 6240. In total 20 lines are detected, including CO J = 4-3 through J = 13-12, 6 H2O rotational lines, and [C I] and [N II] fine-structure lines. The CO to continuum luminosity ratio is 10 times higher in NGC 6240 than Mrk 231. Although the CO ladders of NGC 6240 and Mrk 231 are very similar, UV and/or X-ray irradiation are unlikely to be responsible for the excitation of the gas in NGC 6240. We applied both C and J shock models to the H-2 v = 1-0 S(1) and v = 2-1 S(1) lines and the CO rotational ladder. The CO ladder is best reproduced by a model with shock velocity v(s) = 10 km s(-1) and a pre-shock density n(H) = 5 x 10(4) cm(-3). We find that the solution best fitting the H-2 lines is degenerate. The shock velocities and number densities range between v(s) = 17-47 km s(-1) and n(H) = 10(7)-5x10(4) cm(-3), respectively. The H-2 lines thus need a much more powerful shock than the CO lines. We deduce that most of the gas is currently moderately stirred up by slow (10 km s(-1)) shocks while only a small fraction (less than or similar to 1%) of the interstellar medium is exposed to the high-velocity shocks. This implies that the gas is rapidly losing its highly turbulent motions. We argue that a high CO line-to-continuum ratio is a key diagnostic for the presence of shocks.

Physiological androgen insensitivity of the fetal, neonatal, and early infantile testis is explained by the ontogeny of the androgen receptor expression in Sertoli cells.

Abstract: Context: Although gonadotropins and testosterone are high in the fetal/early postnatal periods, Sertoli cells remain immature and spermatogenesis does not progress. We hypothesized that Sertoli cells do not respond to testosterone because they do not express the androgen receptor. Objective: The objective of the study was to describe the precise ontogeny of androgen receptor expression in the human testis from fetal life through adulthood. Design: This was an immunohistochemical study on testicular biopsies from fetal, neonatal, prepubertal, pubertal, and adult human testes. Main Outcome Measures: Quantification of androgen receptor expression in Sertoli cells was measured. Evaluation of androgen receptor expression in peritubular and interstitial cells as well as anti-Mullerian hormone and inhibin-α was also performed. Results: Androgen receptor expression was first observed in the nuclei of few Sertoli cells at the age of 5 months. Labeling was weak in 2–15% of Sertoli cells until 4 yr of age and progre...

Mapping and inventory of forest fires from digital processing of tm data

Abstract: The application of space‐borne sensors to forest fire mapping and inventory was evaluated. Digital image processing of Thematic Mapper data was used to study a big forest fire on the Mediterranean coast of Spain. The results showed that image processing techniques cannot discriminate perfectly the area affected by the fire. The main problem was spectral overlapping between burned and unburned vegetation especially caused by the sparseness of shrub and confusion with other cover types such as urban/rural villages. Most of these problems can be solved by using visual analysis for masking the affected area, although this strategy is not completely reliable on studies of small forest fires. An inventory of the damaged area was performed in three levels: total area affected by the fire, area by previous vegetation species, and identification of levels of damaged on the burned vegetation.