Controlling mosquitoes through innovative and collaborative wetland management practices in the Pacific Northwest

Wetlands Ecology and Management - When developing a plan to restore or modify a wetland within the Pacific Northwest of the United States (PNW), land managers must consider all of the potential...     

Retinoic acid signalling specifies intermediate character in the developing telencephalon

The organisation of the telencephalon into its major structures depends on its early regionalisation along the dorsoventral axis. Previous studies have provided evidence that sonic hedgehog (SHH) is required for the generation of telencephalic cells of ventral character, and that sequential WNT and fibroblast growth factor (FGF) signalling specifies cells of dorsal telencephalic character. However, the signalling mechanisms that specify telencephalic cells of an intermediate character remain to be defined. We provide evidence here that retinoic acid has a crucial role in specifying telencephalic progenitor cells of intermediate character.     

Ultrasonographic monitoring of fetal development in unrestrained bonobos (Pan paniscus) at the Milwaukee County Zoo

The bonobo, Pan paniscus, is one of the most endangered primate species. In the context of the Bonobo Species Survival Plan^®, the Milwaukee County Zoo established a successful breeding group. Although the bonobo serves as a model species for human evolution, no prenatal growth curves are available. To develop growth graphs, the animals at the Milwaukee County Zoo were trained by positive reinforcement to allow for ultrasound exams without restraint. With this method, the well being of mother and fetus were maintained and ultrasound exams could be performed frequently. The ovulation date of the four animals in the study was determined exactly so that gestational age was known for each examination. Measurements of biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) were used to create growth curves. Prenatal growth of P. paniscus was compared with the data of humans and the common chimpanzee, P. troglodytes. With respect to cranial structures, such as BPD and HC, humans have significant acceleration of growth compared with P. paniscus and P. troglodytes. In P. paniscus, growth of AC was similar to HC throughout pregnancy, whereas in humans AC only reaches the level of HC close to term. Growth rate of FL was similar in humans and the two Pan species until near day 180 post‐ovulation. After that, the Pan species FL growth slowed compared with human FL. The newly developed fetal growth curves of P. paniscus will assist in monitoring prenatal development and predicting birth dates of this highly endangered species. Zoo Biol 30:241–253, 2011. © 2010 Wiley‐Liss, Inc.     

Optimal climate for large trees at high elevations drives patterns of biomass in remote forests of Papua New Guinea

Our ability to model global carbon fluxes depends on understanding how terrestrial carbon stocks respond to varying environmental conditions. Tropical forests contain the bulk of the biosphere's carbon. However, there is a lack of consensus as to how gradients in environmental conditions affect tropical forest carbon. Papua New Guinea (PNG) lies within one of the largest areas of contiguous tropical forest and is characterized by environmental gradients driven by altitude; yet, the region has been grossly understudied. Here, we present the first field assessment of aboveground biomass (AGB) across three main forest types of PNG using 193 plots stratified across 3,100‐m elevation gradient. Unexpectedly, AGB had no direct relationship to rainfall, temperature, soil, or topography. Instead, natural disturbances explained most variation in AGB. While large trees (diameter at breast height > 50 cm) drove altitudinal patterns of AGB, resulting in a major peak in AGB (2,200–3,100 m) and some of the most carbon‐rich forests at these altitudes anywhere. Large trees were correlated to a set of climatic variables following a hump‐shaped curve. The set of “optimal” climatic conditions found in montane cloud forests is similar to that of maritime temperate areas that harbor the largest trees in the world: high ratio of precipitation to evapotranspiration (2.8), moderate mean annual temperature (13.7°C), and low intra‐annual temperature range (7.5°C). At extreme altitudes (2,800–3,100 m), where tree diversity elsewhere is usually low and large trees are generally rare or absent, specimens from 18 families had girths >70 cm diameter and maximum heights 20–41 m. These findings indicate that simple AGB‐climate‐edaphic models may not be suitable for estimating carbon storage in forests where optimal climate niches exist. Our study, conducted in a very remote area, suggests that tropical montane forests may contain greater AGB than previously thought and the importance of securing their future under a changing climate is therefore enhanced.     

Characterizing Latino anglers' environmental risk perceptions,sport fish consumption,and advisory awareness

Sport fish advisories for the Great Lakes states suggest limiting consumption of fish taken from the lakes and their tributaries because of chemical contamination. It appears, however, that minority anglers are less aware of the advisories and also consume greater amounts of sport fish than white anglers. We conducted focus groups in western New York with Latino anglers and partners of anglers to explore these patterns. Analysis revealed that older anglers believed local waters were of good quality and that it was safe to consume fish taken from them. They based their evaluation of both water and fish primarily on visual inspection. In contrast, younger Latinos believed that area waters were highly polluted because of dumping of waste from local industries. They fished away from urban areas in an effort to find cleaner, more swiftly moving waters. They considered consuming sport fish from urban areas highly risky, given their occasional illness experiences following meals of what they thought were polluted fish. For all Latino anglers, however, state-sponsored advisories were minimally effective because of their limited distribution and complex wording. Results point to differences in lay and scientific models of pollution and a need to bridge this gap in future risk-communication strategies.     

Hyperoxia and self- or neutrophil-generated O2 metabolites inactivate xanthine oxidase

Xanthine oxidase (XO) and xanthine dehydrogenase (XD) activities decreased in lungs isolated from rats and cultured lung endothelial cells that had been exposed to hyperoxia. Purified XO activity also decreased after addition of a variety of chemically generated O2 metabolite species (superoxide anion, hydrogen peroxide, hydroxyl radical, or hypochlorous acid), hypoxanthine, or stimulated neutrophils in vitro. XO inactivation by chemically, self-, or neutrophil-generated O2 metabolites was decreased by simultaneous addition of various O2 metabolite scavengers but not their inactive analogues. Since XO appears to contribute to a variety of biological processes and diseases, hyperoxia- or O2 metabolite-mediated decreases in XO activity may be an important cellular control mechanism.     

Methods of semen collection in an ambulatory greater one-horned rhinoceros (rhinoceros unicornis)

Illegal poaching and reduced habitats have led to the endangered status of rhinoceroses. Collection of semen for preservation and future artificial insemination would therefore increase the reproductive potential of the rhinoceros. Although various collection methods have been attemped with individual rhinos, comparison between methods on a single animal have not been reported. This report details the application of six semen collection techniques on an unsedated and unrestrained greater one-horned rhino. The methods included different types of penile and/or rectal stimulation. Artificial vaginas and an inflatible probe for electroejaculation were specially constructed for semen collection. Of the various methods employed, penile massage consistently resulted in sperm-poor seminal fluid, but when preceded by either rectal massage or electroejaculation, seminal fluid with high sperm concentration was obtained.