Diesel oil volatilization processes affected by selected porous media.

Volatilization plays an important role in attenuating petroleum products in contaminated soils. The objective of this study was to evaluate the influence of wind speed, vessel diameter and mean grain size of porous media on diesel oil volatilization. Experiments were conducted to investigate the volatilization behavior of diesel oil from porous media by weighing contaminated samples pre- and post-volatilization. Three selected field porous media materials were evaluated: Silty Clay Loam, Fine Sand, and Coarse Sand along with six individual sand fractions of the Coarse Sand. Results indicate that increasing wind speed accelerates the diesel oil volatilization process, especially for wind speeds below 2.10ms(-1). The low-carbon components of diesel oil volatilize more rapidly, with the effects of wind speed more pronounced on C10 to C15 volatilization than on C16 and higher. The volatilization rate coefficient of diesel oil increases with decreasing mean grain size of porous media, and with increasing vessel diameter. A power function expressed the relationship with mean grain size. All processes (wind speed, vessel diameter, and mean grain size) were included in an equation which explained over 92% of the measured diesel oil volatilization rate coefficient variations for the experiments. Diesel oil volatilization appears to be boundary-layer regulated to some extent.

First detection of Chlamydia psittaci from a wild native passerine bird in New Zealand.

AIMS: To undertake disease surveillance for Chlamydia psittaci in native birds as part of a pilot study to examine pathogen diversity on Hauturu-o-Toi/Little Barrier Island. To retrospectively review the Massey University post-mortem database to determine previous cases of avian chlamydiosis in New Zealand. METHODS: Mistnetting of forest birds was conducted across an elevational gradient on Hauturu-o-Toi/Little Barrier Island. Minitip culture swabs were used to collect cloacal samples from native birds. These swabs were screened for Chlamydia family DNA using two PCR methods. Positive results were sequenced. A retrospective review of the Massey University post-mortem database of all avian cases from 1990 to 2011 was conducted. RESULTS: Ten native birds including four bellbirds (Anthornis melanura), three rifleman (Acanthisitta chloris), two hihi (Notiomyces cincta), and one whitehead (Mohoua albicilla) were sampled and one otherwise healthy female hihi was positive by both PCR screening methods for Chlamydophila. Sequencing confirmed 99-100% genetic similarity to C. psittaci. A retrospective review of the Massey University post-mortem database revealed no previous diagnoses of avian chlamydiosis in wild native New Zealand birds although it has been detected in captive parrots, and wild and captive exotic pigeons. CONCLUSIONS: This is the first report of the detection of C. psittaci from a wild native bird in New Zealand. The bird was a Passeriforme from an endangered species that was captured free-living on Little Barrier Island. The incidence of avian chlamydiosis in native birds in New Zealand appears to be very low, based on the retrospective review of the post-mortem database. CLINICAL RELEVANCE: It is unlikely that avian chlamydiosis is a significant problem for hihi population health. The detection of this organism has greater significance for other more susceptible species on Little Barrier Island and for human health, particularly for conservation workers involved in wildlife translocations. It further suggests that passerine birds may be a reservoir for C. psittaci in New Zealand ecosystems.

Aldicarb and carbofuran transport in a Hapludalf influenced by differential antecedent soil water content and irrigation delay.

Pesticide use in agroecosystems can adversely impact groundwater quality via chemical leaching through soils. Few studies have investigated the effects of antecedent soil water content (SWC) and timing of initial irrigation (TII) after chemical application on pesticide transport and degradation. The objectives of this study were to investigate the effects of antecedent soil water content (wet vs dry) and timing of initial irrigation (0h Delay vs 24h Delay) on aldicarb [(EZ)-2-methyl-2-(methylthio)propionaldehyde O-methylcarbamoyloxime] and carbofuran [2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate] transport and degradation parameters at a field site with Menfro silt loam (fine-silty, mixed, superactive, mesic Typic Hapludalf) soils. Aldicarb and carbofuran were applied to plots near field capacity (wet) or near permanent wilting point (dry). Half of the dry and wet plots received irrigation water immediately after chemical application and the remaining plots were irrigated after a 24h Delay. The transport and degradation parameters were estimated using the method of moments. Statistical significance determined for SWC included averages across TII levels, and significance determined for TII included averages across SWC levels. For the dry treatment, aldicarb was detected 0.10 m deeper (P<0.01) on two of the four sampling dates and carbofuran was detected at least 0.10 m deeper (P<0.05) on all of the sampling dates compared to the wet treatment. Pore water velocity was found to be higher (P<0.10) in the dry vs wet treatments on three of four dates for aldicarb and two of four dates for carbofuran. Retardation coefficients for both pesticides showed similar evidence of reduced values for the dry vs wet treatments. These results indicate deeper pesticide movement in the initially dry treatment. For aldicarb and carbofuran, estimated values of the degradation rate were approximately 40-49% lower in the initially dry plots compared to the initially wet plots, respectively. When the initial irrigation was delayed for 24h, irrespective of antecedent moisture conditions, a 30% reduction in aldicarb degradation occurred. This study illustrates the deeper transport of pesticides and their increased persistence when applied to initially dry soils.

Atrazine and alachlor transport in claypan soils as influenced by differential antecedent soil water content.

Increased attention to ground water contamination has encouraged an interest in mechanisms of solute transport through soils. Few studies have investigated the effect of the initial soil water content on the transport and degradation of herbicides for claypan soils. We investigated the effect of claypan soils at initial field capacity vs. permanent wilting level on atrazine and alachlor transport. The soil studied was Mexico silt loam (fine, smectitic, mesic Aeric Vertic Epiaqualf) with a subsoil clay content, primarily montmorillonite, of >40%. Strontium bromide, atrazine, and alachlor were applied to plots; half were at field capacity (Wet treatment), and half were near the permanent wilting point (Dry treatment). Soil cores were removed at selected depths and times, and cores were analyzed for bromide and herbicide concentrations. Bromide, atrazine, and alachlor were detected at the 0.90-m depth in dry plots within 15 d after experiment initiation. Bromide was detected 0.15 m deeper (P < 0.05) in the Dry compared with the Wet treatment at 1, 7, and 60 d after application and >0.30 m deeper (P < 0.01) in the Dry treatment at 15 and 30 d after application; similar treatment results were found for atrazine and alachlor, although on fewer dates with significant differences. The mobility order of the applied chemicals was bromide > atrazine > alachlor. The atrazine apparent half-life was significantly longer in the Dry plots compared with the Wet plots. The retardation factor determined from the relative velocity of each herbicide to that of bromide was higher for alachlor than for atrazine. This study identifies the impact that shrinkage cracks have for different moisture conditions on preferential transport of herbicides in claypan soils.

Performance of grass barriers and filter strips under interrill and concentrated flow.

Effectiveness of grass barriers and vegetative filter strips (FS) for reducing transport of sediment and nutrients in runoff may depend on runoff flow conditions. We assessed the performance of (1) switchgrass (Panicum virgatum L.) barriers (0.7 m) planted above fescue (Festuca arundinacea Schreb.) filter strips under interrill (B-FS) and concentrated flow (CF-B-FS), and (2) fescue alone under interrill (FS) and concentrated flow (CF-FS) for reducing runoff, sediment, nitrogen (N), and phosphorus (P) loss from fallow plots on a Mexico silt loam. We compared exclusively the performance of barriers and filter strips separately under interrill and concentrated flow. Runoff and sediment were sampled at 1 m above and at 0.7, 4, and 8 m below the downslope edge of the sediment source area. Filter strips under interrill flow reduced 80% and those under concentrated flow reduced 72% of sediment at 0.7 m (P < 0.01). With the addition of supplemental runoff simulating runoff from a larger sediment source area, FS reduced 80%, but CF-FS reduced only 60% of sediment. The FS reduced organic N and NO(3)-N by an additional 50% (P < 0.01) more than CF-FS at 0.7 m. Although the effectiveness of both treatments increased with increasing width, CF-FS removed less sediment than FS alone at 8 m (P < 0.04). In contrast, barriers above filter strips under interrill and concentrated flow were equally effective at 8 m; decreasing runoff by 34%, sediment by 99%, and nutrients by 70%. Thus, barriers combined with FS can be an effective alternative to FS alone for sites where concentrated flows may occur.

A provisional database for the silicon content of foods in the United Kingdom.

Si may play an important role in bone formation and connective tissue metabolism. Although biological interest in this element has recently increased, limited literature exists on the Si content of foods. To further our knowledge and understanding of the relationship between dietary Si and human health, a reliable food composition database, relevant for the UK population, is required. A total of 207 foods and beverages, commonly consumed in the UK, were analysed for Si content. Composite samples were analysed using inductively coupled plasma-optical emission spectrometry following microwave-assisted digestion with nitric acid and H(2)O(2). The highest concentrations of Si were found in cereals and cereal products, especially less refined cereals and oat-based products. Fruit and vegetables were highly variable sources of Si with substantial amounts present in Kenyan beans, French beans, runner beans, spinach, dried fruit, bananas and red lentils, but undetectable amounts in tomatoes, oranges and onions. Of the beverages, beer, a macerated whole-grain cereal product, contained the greatest level of Si, whilst drinking water was a variable source with some mineral waters relatively high in Si. The present study provides a provisional database for the Si content of UK foods, which will allow the estimation of dietary intakes of Si in the UK population and investigation into the role of dietary Si in human health.

Acute liver failure as the initial manifestation of acute leukaemia.

BACKGROUND/AIMS: Haematological malignancies seldom cause clinically significant liver disease. Acute liver failure as the initial manifestation of acute leukaemia is very rare and carries a very poor prognosis. METHODS/RESULTS: Three cases of acute liver failure secondary to acute leukaemia are described. Each case presented initially as acute liver failure of uncertain cause. Specific treatment for the leukaemia was instituted; however, all three patients died as a consequence of the liver failure. We describe the clinical course and relevant investigations of these patients and discuss possible mechanisms of acute liver failure in this setting. CONCLUSION: Acute leukaemia presenting as acute liver failure has a very poor prognosis. Although a rare cause of acute liver failure, it should be considered in any patient presenting with acute liver failure with prodromal symptoms and a raised peripheral white cell count, lactate dehydrogenase and uric acid.

Effects of pyriproxyfen spray, powder, and oral bait treatments on the relative abundance of nontarget arthropods of black-tailed prairie dog (Rodentia: Sciuridae) towns.

Separate black-tailed prairie dog, Cynomys ludovicianus (Ord), towns on the Rocky Mountain Arsenal National Wildlife Refuge, Colorado, were treated with technical pyriproxyfen (Nylar) spray, powder, and oral bait. The treatments were applied to reduce relative abundance of the plague vector Oropsylla hirsuta (Baker). Because pyriproxyfen is a juvenile hormone analog, we were also concerned with the effects of the treatments on nontarget arthropods, which is the focus of this study. Pitfall traps and sweep net sampling were used to measure relative abundance of arthropod populations pre- and posttreatment. Nontarget arthropod sampling produced a large number of statistical comparisons that indicated significant declines (P < 0.05) in relative arthropod abundance. Many of the significant declines were probably because of natural fluctuations in arthropod populations rather than treatment effects. Because arthropod populations appeared to fluctuate randomly, we only made inferences about highly significant (P < 0.001) declines. In doing so, we hoped to abate some of the confusion created by the natural fluctuation in arthropod abundance and increase our chance of correctly attributing a population reduction to a treatment effect. Only Homoptera at the pyriproxyfen powder site exhibited highly significant reductions that appeared to be attributed to the treatments. Pyriproxyfen spray treatments did not significantly reduce relative arthropod abundance.

Malignant acanthosis nigricans: potential role of chemotherapy.

Acanthosis nigricans is an uncommon skin condition characterized by hyperkeratosis and skin hyperpigmentation. Most causes are benign, but it may also be associated with gastrointestinal and other malignancies. When associated with malignant disease, the skin pathology may be more severe and treatment often unsuccessful. We describe a 66-year-old man with acanthosis nigricans associated with carcinoma of the stomach, with distressing generalized cutaneous, perioral and perineal disease, whose skin condition resolved completely with combination chemotherapy. In patients with malignant acanthosis, chemotherapy may relieve many of the distressing cutaneous symptoms. A close liaison between gastroenterologists, dermatologists and oncologists is required.

Plague in a complex of white-tailed prairie dogs and associated small mammals in Wyoming.

Fleas were collected from white-tailed prairie dogs (Cynomys leucurus) and other small mammals trapped on six grids during a field study near Meeteetse (Wyoming, USA) in 1989 and 1990 to investigate the dynamics of plague in this rodent population. Fleas were identified and tested for Yersinia pestis by mouse inoculation. Yersinia pestis-positive fleas were found on prairie dogs and in their burrows. Flea species on prairie dogs changed from spring to late summer. White-tailed prairie dog numbers were significantly lower in the presence of Y. pestis-positive fleas; however, affected populations generally recovered 1 to 2 yr following absence of detectable plague. Grids where recovery occurred had a high proportion of juvenile male prairie dogs. Eighteen flea species were identified on small mammals, six of which were infected with Y. pestis. Some flea species were associated with a particular small mammal species, while others were found on a broad range of host species. Flea species most important in the potential interchange of Y. pestis between associated small mammals and white-tailed prairie dogs were Oropsylla tuberculata cynomuris, Oropsylla idahoensis, and Oropsylla labis. Plague cycled through the white-tailed prairie dog complex in an unpredictable manner. Each summer the complex was a mixture of colonies variously impacted by plague: some were declining, some were unaffected by plague, and others were recovering from plague population declines. These data provide insight into the dynamics of plague in white-tailed prairie dog complexes, but predicting movement of plague is not yet possible and the role of associated mammals in maintenance of plague is not understood.

The Acoustic Neuroma Association.

The Acoustic Neuroma Association (ANA) was established in 1981 in an effort to improve patients' treatment experiences and subsequent recovery by providing realistic and accurate patient information and by offering opportunities for positive interaction with other acoustic tumor patients. A history of the organization is given along with a description of publications and other ways the ANA can be a useful resource for patients and physicians. The ANA's growth since its founding demonstrates its usefulness to patients and physicians.

Use of octreotide in the treatment of mesenteric angina.

The case of a 57-yr-old man with a medical history of generalized atherosclerotic disease and newly diagnosed intestinal ischemia is presented. Because the patient was a poor surgical and anesthetic risk, medical treatment in the form of octreotide was administered with remarkable symptomatic relief. This is the first published report of the use of octreotide in treating mesenteric angina.

Effect of macromolecules from oviductal conditioned medium on bovine sperm motion and capacitation.

The effect of macromolecules from oviductal conditioned medium (CM) on sperm motility and capacitation was studied. Sperm pooled from three bulls was incubated in either luteal isthmic CM, luteal ampullary CM, estrual isthmic CM, estrual ampullary CM, or control medium (no CM) for 4 h. Sperm capacitation and motility were assessed at 10 min and 4 h. Estrual isthmic CM capacitated significantly more spermatozoa at 4 h than estrual ampullary CM or control medium. CM also affected lateral head movement (ALH) and beat cross-frequency (BCF) of sperm. In a second experiment, the glycosaminoglycan (GAG) content of the different types of oviductal CM was quantified. Estrual isthmic CM contained more GAG than estrual ampullary CM. Among luteal samples, no difference in GAG concentration between the isthmic and ampullary CM was found. Heat treatment (100 degrees C) of oviductal CM before coincubation with sperm significantly reduced, but did not eliminate, the capacitating ability. Because heat treatment denatures proteins and decreases the capacitating ability of certain GAG, we concluded that the capacitating effect of estrual isthmic CM may be associated with proteins, GAG, and proteoglycans in the CM. Isthmic secretions may play a major role during in vivo sperm capacitation, given that bovine spermatozoa may reside in the oviduct isthmus for up to 18 h before fertilization.

Cholesterol, phospholipid and phospholipase activity of ampullary and isthmic fluid from the bovine oviduct.

Cholesterol and phospholipid concentrations and phospholipase activity were measured in fluid from cannulae collected from the bovine oviductal isthmus and ampulla at different stages of the oestrous cycle. The cholesterol concentration and cholesterol normalized by protein were significantly (P = 0.03) greater in isthmic oviductal fluid (224.3 +/- 42.7 micrograms ml-1 over all stages) than in ampullary oviductal fluid (164.5 +/- 11.3 micrograms ml-1), and maximal concentrations (284.5 +/- 25.5 micrograms ml-1) were found during the luteal stage (serum progesterone concentration > or = 1.5 ng ml-1). The concentrations of the phospholipids sphingomyelin and lysophosphatidylcholine increased at different stages of the cycle and in different regions. In the ampulla, the concentration of sphingomyelin was significantly (P < 0.05) greater in oviductal fluid collected during the luteal phase (12.1 +/- 2.7% of total phospholipids) than in fluid collected near oestrus and ovulation (7.5 +/- 1.5% and 6.9 +/- 1%, respectively). The concentration of lysophosphatidylcholine was greater (P < 0.01) in ampullary (19.2 +/- 1.6% of total phospholipids) than in isthmic oviductal fluid (9.9 +/- 1.1%) collected near ovulation. The ratio of cholesterol to total phospholipid was highest in oviductal fluid collected from the isthmus during all stages (2.3 micrograms ml-1:% total phospholipid), while the minimal ratio was found in ampullary fluid collected near ovulation (1.5). Phospholipase activity was higher (P = 0.03) in isthmic oviductal fluid (20.4 +/- 3.2% product formed) than in ampullary oviductal fluid (14.6 +/- 1.4%); the lowest activity (12.6 +/- 1.7% product formed) was in fluid collected during the phase of the oestrous cycle immediately before ovulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of bovine oviductal estrus-associated protein on the ability of sperm to capacitate and fertilize oocytes.

At estrus, an oviduct-specific, estrus-associated glycoprotein (EAP) of molecular weight 85-95,000, is secreted by the oviductal epithelium and found in cannula-derived bovine oviductal fluid (ODF). The objectives of these studies were to determine if bovine sperm were capacitated by EAP in vitro, whether this effect differed for EAP derived from ODF versus conditioned medium from oviduct ampullar explants, and to determine if sperm capacitated in vitro with EAP-fertilized bovine eggs. Sperm were incubated for up to 6 hours with partially purified EAP derived from ODF and assessed for capacitation by their ability to undergo the acrosome reaction following exposure to lysophosphatidylcholine. At 4 hours of incubation, the number of capacitated sperm in treatments containing 50% ODF or EAP plus bovine serum albumin (BSA) was similar, and it was significantly greater than the number of capacitated sperm in treatments containing antibodies to EAP. Using purified EAP derived from ampullar explant-conditioned medium, twice the number of sperm were capacitated after 4 hours with EAP from conditioned medium or with ODF than with treatments containing anti-EAP. The fertilizing ability of sperm incubated with EAP was significantly greater than that for sperm incubated without EAP or with anti-EAP. We conclude that bovine EAP, derived from both ODF and in vitro cultures, promotes sperm fertilizing ability.

Identification of a high-affinity glycine betaine transport system in Staphylococcus aureus.

Staphylococcus aureus accumulates proline and glycine betaine when cells are grown at low water activity. In the present study, we have identified a high-affinity glycine betaine transport system in this bacterium. Optimal activity for this transport system was measured in the presence of high NaCl concentrations, but transport activity was not stimulated by high concentrations of other solutes.

Cation concentrations in fluid from the oviduct ampulla and isthmus of cows during the estrous cycle.

To detect variations in oviduct fluid cation concentrations, Ca++, Mg++, K+, and Na+ were determined for daily samples of blood serum and bovine oviduct fluid collected from indwelling isthmic and ampullary catheters. Isthmic oviduct fluid Ca++ concentration was significantly greater than that in ampullary fluid, particularly around estrus and ovulation. Maximum Ca++ concentrations found in isthmic oviduct fluid at estrus (2.57 +/- .22 mM) and at ovulation (2.50 +/- .29 mM) were similar to those of medium used for in vitro capacitation of bovine sperm. Concentrations of Mg++ in oviduct fluid differed significantly by estrous cycle stage, but not by oviduct region, and were consistently lower than those detected in serum. No relationships were found for K+ or Na+ with respect to region or stage, but K+ was generally higher in oviduct fluid than in serum. The concentration of K+ averaged over stage and region (4.46 +/- .13 mM) and the K+:Na+ ratio (.032 +/- .002) were similar to those reported in bovine in vitro capacitating and fertilizing media. Concentrations of Ca++ and Na+ from peritoneal fluid from nonstaged cows were similar to those of oviduct fluid or serum. The Mg++ concentration was greater, and K+ concentration was less, in peritoneal than in oviduct fluid.