Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre occidental Mexico

The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on standing dead trees (snags). This report is based on an 11 month field survey that aimed to locate oldgrowth remnants and to assess the status of the endemic birds. Old-growth is defined here as a forest that has never been logged mechanically. Old-growth forests were located by ground-truthing of areas predicted by various methods: analyses of topographical maps and satellite images, aerial surveys, interviews with forestry technicians and local inhabitants, and literature studies. None of the prediction methods gives unambiguous results on their own. Only by applying the whole set of techniques could a comprehensive inventory be obtained of old-growth sites. Of the original 93, 560 km² of pine-oak habitat in the Sierra Madre Occidental, 571 km² remained as old-growth in 1995. This is a reduction of 99.4 %. The forests on high mesas, where the largest and most accessible timber stood, have been reduced to 22 km² uncut forest. In logged forests pines greater than 30 cm girth have been extracted and snags have been cut for the production of paper pulp. Small settlements are everywhere. Information on the Imperial Woodpecker Campephilus imperialis was obtained through interviews with 62 elder inhabitants who had known the bird. The extinction peak of this species was between 1946 and 1965, when 60 % of the informants saw their last Imperial Woodpecker. Hunting by settlers and loggers, for fun and for medicinal purposes, quickly decimated populations. Recovery from the shooting became impossible through the ensuing logging of nearly all the pine-oak habitat. Mature pines and pine snags were removed, depriving the Imperial Woodpecker of foraging and nesting sites. Imperial Woodpeckers were often seen in groups. A typical group consisted of seven or eight birds. With an estimated average density of one Imperial Woodpecker per 13 km², the original pine-oak habitat in the whole range of the species may have carried only 8,000 individuals or 1060 groups. Interviews, and workings found in one old-growth area, indicate that very few Imperial Woodpeckers may have survived into the 1990s. Extinction of the species seems nevertheless inevitable since nowhere does any breeding habitat remain. Cutting of snags is the main threat to the Thick-billed Parrot Rhynchopsitta pachyrhyncha. This species only breeds at altitudes above 2300 m, but snags are scarce on the exploited mesa forests in the highest parts of the sierra. The breeding range runs from within 85 km of the US border in northern Chihuahua south to central western Durango, with an apparent gap in southern Chihuahua. Pine seeds for foraging are widely available in young recovering forest. Compared with historical records, encountered groups of wintering Thick-billed Parrots were small, few groups were seen, and the numbers of bathing and drinking parrots at a waterfall in northern Chihuahua were low. This indicates numbers have sharply declined in the course of the 20th century. The status of the Eared Trogon Euptilotis neoxenus is far less critical. Eared Trogons were observed at 55 locations, mainly in canyons. Nests were found in riparian corridors in canyons. Such corridors are hardly accessible to the logging industry. The ability, and probable preference, of the Eared Trogon to breed in canyons likely explains why it is still fairly common. The erroneous notion that the Eared Trogon is a local and rare species must stem from the paucity of field studies in the Sierra Madre Occidental, as well as the wariness of the bird. It is mostly to be detected by its vocalizations. Efforts are being made to ensure the total protection of three priority areas (figures 26 to 28). These areas encompass the main old-growth fragments in the Sierra Madre Occidental. They are also of major importance to the endemic fauna. Protection of snags is required for three breeding areas of the Thick-billed Parrot (figures 29 to 31). Ideally, exploitation of snags should be banned throughout the Sierra Madre Occidental

The Drosophila melanogaster Genetic Reference Panel

A major challenge of biology is understanding the relationship between molecular genetic variation and variation in quantitative traits, including fitness. This relationship determines our ability to predict phenotypes from genotypes and to understand how evolutionary forces shape variation within and between species. Previous efforts to dissect the genotype-phenotype map were based on incomplete genotypic information. Here, we describe the Drosophila melanogaster Genetic Reference Panel (DGRP), a community resource for analysis of population genomics and quantitative traits. The DGRP consists of fully sequenced inbred lines derived from a natural population. Population genomic analyses reveal reduced polymorphism in centromeric autosomal regions and the X chromosome, evidence for positive and negative selection, and rapid evolution of the X chromosome. Many variants in novel genes, most at low frequency, are associated with quantitative traits and explain a large fraction of the phenotypic variance. The DGRP facilitates genotype-phenotype mapping using the power of Drosophila genetics

Fiber optical improvements for a device used in laparoscopic hysterectomy surgery

Hysterectomy removes uterus from patients suffering different pathologies. One of the most common techniques for performing it is the laparoscopically- assisted vaginal hysterectomy (LAVH). In the final stage of the procedure, surgeons face the need to unambiguously identify the vaginal cuff before uterus removal. The aim of this research is to adapt a local source of illumination to a polymer cup-like device adapted to a stainless steel shaft that surgeons nowadays use to manipulate the uterus in LAVH. Our proposal consists in implementing a set of optical fiber illuminators along the border of the cup-like device to illuminate the exact vaginal cupola, using an external light source. We present experimental results concerning temperature increases in quasi adiabatic conditions in cow meat under different light intensity illumination. © 2006 American Institute of Physics

Reusable PdO/Al2O3-Nd2O3 photocatalysts in the UV photodegradation of phenol

The UV photodegradation of phenol in aqueous medium using PdO supported on binary Al2O3-Nd2O3 oxides as photocatalysts was studied. The PdO/Al2O3-Nd2O3 photocatalysts were prepared by the sol-gel method and characterized by N2 physisorption, XRD, Raman spectroscopy and UV-vis diffuse reflectance spectroscopy. Bare PdO/γ-Al2O3 was found active for the photodegradation of phenol in aqueous medium. However, the addition of Nd2O3 to the γ-Al2O3 improves the photocatalytic activity of PdO photocatalysts as well as the decrease of dissolved organic carbon in aqueous milieu. Highest photocatalytic activity of PdO photocatalysts was observed for 10wt% of Nd2O3 added to the γ-Al2O3 increasing the activity by a factor of two with respect to that of PdO/γ-Al2O3 after six hours of irradiation. The photocatalytic activity in the degradation of phenol by using the recovered PdO/Al-Nd photocatalysts is preserved after reaction. © 2013 Elsevier B.V