Fluoride adsorption by a saline sodic soil irrigated with a high F water

Summary Langmuir isotherm data for F adsorption were obtained from 1:10 soil:water extracts of soil samples from a lysimeter study. A sodic silt loam surface soil with a saline sodic subsoil was irrigated with a high sodium chloride, high fluoride (0.38 mMF) geothermal well water. A previous study showed that fluorite (CaF₂) was precipitated from solution in the upper portion of this profile while another mechanism removed F solution in the lower part of the profile to below 0.02 mMF. The Langmuir isotherm data indi cate that one kind of surfaces or sites remove fluoride from solution over the 0 to 1.1 to 1.2 mMF range. The adsorption capacity for this F removal is about 4.4 to 5.8 mmol F/kg of soil and the equilibrium constant is between 0.54 to 1.001/mmol F. Once these surfaces or sites were saturated, a second kind of sites removed F from solution, and had an adsorption capacity of 9.2 to 11.4 mmol/kg and an equilibrium constant of 0.16 to 0.271/mmol. Both data sets fit the Langmuir equation. At some point before or after this second set of sites or surfaces was saturated, the fluorite ion activity product was exceeded and fluoride was then removed from solution via fluorite precipitation. The two adsorption mechanisms lowered the soil solution F concentration sufficiently to prevent ground water contamination, but once the adsorption sites were saturated, fluorite precipitation does not decrease F concentration sufficiently to meet drinking water standards.Contribution from USDA-ARS, Snake River Conservation Research Center, Kimberly, ID 83341, USA     

Open reduction of sacral fractures using transarticular implants at the articular facets of L7-S1: 8 consecutive canine patients (1995-1999)

OBJECTIVE: To describe and evaluate facet stabilization as an aid for open reduction and fixation of sacral fractures. STUDY DESIGN: A clinical case series. STUDY POPULATION: Eight consecutive client-owned dogs with sacral fractures. METHODS: A combination of a standard lateral approach to the ilium and a dorsal approach to the articular facets of L7-S1 was performed. The articular facets were reduced and stabilized with a Kirschner wire or a combination of a Kirschner wire and a cortical screw. Primary stabilization of the sacrum was then accomplished using a cortical screw inserted from the lateral aspect of the ilium, through the sacral fracture into the body of the sacrum. Accuracy of reduction, position of the implants, percent screw depth/sacral width, pelvic canal diameter ratio, and complications were assessed using radiographs and physical examination. RESULTS: Mean sacral fracture reduction was 91% immediately after surgery, and was 87% when measured at follow-up examinations. Mean screw depth/sacral width was 66%. Mean pelvic canal diameter ratio was 1.12 postoperatively and 1.03 at the 4- to 6-week reevaluation. Six of the 8 dogs were using the leg well 10 to 12 days after surgery; none had clinically detectable neurologic deficits. The long-term (mean, 2.7 years) outcome for these dogs was good (normal to grade I lameness). CONCLUSION: Fixation of the L7-S1 facet joints facilitates repair of sacral fractures.     

Successful treatment of mandibular squamous cell carcinoma in a Malayan sun bear (Helarctos malayanus).

An adult, female Malayan sun bear (Helarctos malayanus) was diagnosed with squamous cell carcinoma of the rostral mandible. Initial treatment included bilateral mandibulectomy rostral to the lingual frenulum followed by intra- and perilesional cisplatin injections. Recovery after the procedure was uneventful and the Malayan sun bear adapted well to a shortened mandible. Histopathology indicated incomplete surgical excision of the tumor; therefore, radiation therapy was instituted weekly for four treatments at 2 Gy in parallel opposed fields (total 4 Gy each treatment) with one additional cisplatin treatment. Two years after initial presentation, the animal showed no recurrence of neoplasia.     

Clostridium septicum myositis in a western lowland gorilla (Gorilla gorilla gorilla).

A 10-yr-old male gorilla (Gorilla gorilla gorilla) with a history of conspecific bite wounds was evaluated for acute onset of depression, anorexia, and right hemiparesis. The animal was immobilized for diagnostic examination and treatment for suspected toxic shock from a necrotizing, emphysematous wound infection, but was euthanized due to complications during recovery. Gross and histopathologic examination revealed acute necrotizing myositis, fasciitis, cellulitis, and emphysema in the affected wound area, with large numbers of large Gram-positive rods among necrotic muscle fibers. Severe pulmonary edema with airways containing fibrin, acute hemorrhage in multiple body sites, thrombosis in blood vessels in the skeletal muscle, liver, and lung, and lymph node hyperplasia with lymphoid necrosis and hemorrhage. Immunohistochemical fluorescent antibody staining of muscle from the wound site was positive for     

Parasites of free-ranging small canids and felids in the Bolivian Chaco.

Parasite surveys of free-ranging wildlife provide important information for monitoring population health. Between March 2001 and March 2003, we sampled 10 ocelots (Leopardus pardalis), eight Geoffroy's cats (Oncifelis geoffroyi), a jaguarundi (Herpailurus yaguarondi), five pampas foxes (Pseudalopex gymnocercus), and three crab-eating foxes (Cerdocyon thous) at three sites in the Bolivian Chaco. The objective of the study was to survey the parasite fauna of these carnivores and compare prevalence of parasites among the sites. The parasite community of these carnivores was diverse, with representatives from eight genera of nematodes, two families of cestodes, two protozoan species, and six arthropod species. Fecal parasites identified from 12 of the 13 felids and five of the six canids examined included Aelurostrongylus abstrusus, Ancylostoma tubaeforme, Uncinaria sp., Crenosoma sp., Toxocara cati, Spirurida, Capillaria aerophila, Spirometra sp., Taeniidae, and Cystoisospora sp. Four tick species, Amblyomma parvum, A. tigrinum, A. ovale, and A. cajennense, and two flea species, Pulex irritans and Delostichus phyllotis, were identified. Two crab-eating foxes had serologic evidence of heartworm disease (HWD). Antibodies against Toxoplasma gondii were found in 15 of 26 animals. Although HWD was found only in canids inside the national park, parasite prevalence did not appear to differ among sites, and no evidence was found of parasite spillover from domestic to wild carnivores.     

China's role in the global forest sector: how will the US recovery and a diminished Chinese demand influence global wood markets?

Over the last decade, while the size of China's economy more than doubled, China has simultaneously become a major producer and exporter of forest products. Although China's domestic supply of wood is significantly constrained both by a limited natural supply and by conservation-oriented policies, the country is increasingly regarded as the world's “wood workshop.” Furthermore, China is the largest driver of demand for the trade in tropical logs and is becoming a significant driver of demand for trade in coniferous logs. In this paper, we describe a spatial equilibrium model adapted to study forest sector markets and policies that affect them. We present the model and the result of two alternative future scenarios. The first scenario analyzes the impact on global forest products markets of a US recovery in wood markets. The second scenario examines the effect on global forest products markets of decelerating growth in Chinese demand for wood products. Through these two scenarios, the modeling output sheds light on the role China's wood products markets have on resource supply and trade around the world. The trade model shows substantial potential changes in global prices, production, and trade activity associated with the recovery in domestic demand in the USA.     

Improved discrimination of self-incompatibility S-RNase alleles in cherry and high throughput genotyping by automated sizing of first intron polymerase chain reaction products

A novel polymerase chain reaction (PCR) approach to determine and confirm the self‐incompatibility (S) genotype of cherries is reported. The method involves PCR amplification with a new pair of consensus primers that immediately flank the first intron of cherry S‐RNases, one of which is fluorescently labelled. Fluorescent amplification products range from 234 to c. 460 bp and can be sized accurately on an automated sequencer. Thirteen S alleles reported in sweet cherry can be distinguished, except for S₂ and S₇, which have an amplification product of exactly the same size. S₁₃, which is also amplified, gives a microsatellite‐like trace which shows minor intra‐allelic length variation. This method gives fast and accurate results and should be especially useful for medium/high‐throughput genotyping of wild and cultivated cherries.     

Modified Pollard transects for assessing tropical butterfly abundance and diversity

This paper introduces and discusses the consistency and effectiveness of an inexpensive modification of Pollard transects for assessing the diversity and abundance of tropical butterfly communities in two national parks in Rio de Janeiro, Brazil. To measure butterfly abundance, students walked simultaneous timed transects at the interface of forest and cleared areas. They either counted the number of individuals observed or tabulated the number of specimens collected with nets. After a short training period, the number of butterflies observed or collected on simultaneous transects was statistically indistinguishable among student groups, and there was a significant positive correlation between observation counts and collected number of individuals. As a measure of species richness, the number of butterfly species sampled on each simultaneous transect was tabulated and did not differ statistically. To measure diversity, alpha of the logseries model was calculated for each collected sample, and statistical fit to a logseries model was determined. Although virtually all daily samples and the year's accumulated sample at one park fit the logseries model, about 35% of the daily samples and the entire year's sample did not fit at the other park. Despite these differences between the two parks, values for alpha from daily samples at both parks varied similarly (from 15 to 50 in almost all cases), and values from the entire year's samples were statistically indistinguishable. The repeatability of results among novices, such as students, suggests that timed transects have great promise for furthering our understanding of butterfly community demographics.     

Acoustic stimulation as a tool in African wild dog conservation

A 9-year study of the African wild dog, Lycaon pictus, was conducted in Hwange National Park, Zimbabwe, primarily in Colophospermum mopane woodland and Combretum thicket. A protocol using both playbacks and human simulations of long distance calls was developed to facilitate radio-collaring operations and data collection. Wild dogs were known to be in the area prior to each trial (n=32). Dogs approached calling stations in 84% of trials from distances up to 2-km. When dogs hooed (n=18; eight packs and one group), they approached the stimulus in all but one trial. Mean time to approach was ca. 13.9±2.6 min. (n =11 trials, range 1-56 min). Findings demonstrate that playbacks are an effective conservation tool particularly where road networks are limited and/or thick habitat restrict off-road driving. Potential application lies in park boundary areas where snaring occurs and in translocations from areas of high wild dog/human conflict to refuges. In dense habitat or less traveled areas, this technique, in conjunction with other methods, may prove useful in population surveys.