The Use of Surfactants as Possible Enhancers in Bioremediation of Creosote Contaminated Soil     

Atagana  H. I.  Haynes  R. J.  Wallis  F. M. 《Water, air, and soil pollution》2003,142(1-4):137-149

A study on five nonionic surfactants (Arkopal-N-060, Arkopal-N-080, Arkopal-N-100, Hosaf-541-KS and Tween-80)commercially available in South Africa was carried out todetermine their effect on the desorption and degradation ofcreosote in a soil contaminated with 250 000 mg kg^-1creosote with a view to developing a cost effective methodologyfor treating creosote contaminated soils. The surfactants werestudied in concentrations of 0.01, 0.1, 0.35, 0.5 and 1.0% (v/v) in liquid cultures. Results from the studies showedthat all the surfactants studied were able to enhance thedesorption and degradation of creosote to different extents. Theenhancement ranged from as little as <10% in 0.1% surfactant toas high as 45% in 0.5% surfactant. The effect on degradation ofcreosote was more obvious (30–65%) in the different surfactantsat different concentrations. Arkopal-N-060 was observed to be themost effective in the desorption and degradation of creosote. Theeffect of Hosaf-541-KS on the degradation of creosote was foundto be comparable with those of Arkopal-N-060, however, itsdesorption capabilities were much lower than those of Arkopa-N-060.The concentration of the surfactant was found to play asignificant role in desorption of creosote. It was observed thatsurfactant concentrations of 0.35 and 0.5% were the mosteffective in the desorption of creosote. Above and below theseconcentrations, the effect of the surfactants was observed todecrease. All surfactants studied were not found to inhibitmicrobial growth at the concentrations studied.  相似文献   

Temperature and Thermal Emissivity of the Surface of Neptune's Satellite Triton     

Nelson RM  Smythe WD  Wallis BD  Horn LJ  Lane AL  Mayo MJ 《Science (New York, N.Y.)》1990,250(4979):429-431

Analysis of the preliminary results from the Voyager mission to the Neptune system has provided the scientific community with several methods by which the temperature of Neptune's satellite Triton may be determined. If the 37.5 K surface temperature reported by several Voyager investigations is correct, then the photometry reported by the imaging experiment on Voyager requires that Triton's surface have a remarkably low emissivity. Such a low emissivity is not required in order to explain the photometry from the photopolarimeter experiment on Voyager. A low emissivity would be inconsistent with Triton having a rough surface at the approximately 100-microm scale as might be expected given the active renewal processes which appear to dominate Triton's surface.  相似文献   

Thermal antinociceptive pharmacodynamics of 0.1 mg kg⁻¹ hydromorphone administered intramuscularly in cats and effect of concurrent butorphanol administration     

BDX  Lascelles †  SA Robertson‡  PM Taylor§  J Hauptman¶ 《Veterinary anaesthesia and analgesia》2003,30(2):107-108

Hydromorphone (HY) has not been objectively assessed as an analgesic in cats. It has been suggested that butorphanol (B) can have a synergistic action with pure μ‐agonists. The aim of this study was to assess the antinociceptive activity of a single dose of HY, and to examine the effect of concurrent B administration on the thermal threshold (TT). Thermal thresholds were measured following IM administration of HY, B, a combination of B and HY (HY‐B), or saline (S). Six cats (four spayed females, two castrated males, 4.75–6.8 kg) were used. Each cat received HY (0.1 mg kg^?1), B (0.4 mg kg^?1), HY (0.1 mg kg^?1), and B (0.4 mg kg^?1) (HY‐B), or S (0.05 mL kg^?1) in a randomized, blinded, cross‐over study design. Each cat received each treatment, with at least 12 days interval between the treatments. All injections were IM randomized to left or right quadriceps using a 24 SWG needle. Twenty‐four hours prior to each study, the thorax of each of the cats was shaved. On the day of the study, TT was measured using a thorax‐mounted thermal threshold‐testing device specifically developed for cats. Skin temperature was recorded before each test and then the heater was activated. When the cat responded by flinching, turning, or jumping, the stimulus was terminated and the threshold temperature was recorded. Three baseline thresholds were recorded over 1 hour before IM injection of test drug. Thermal threshold cut‐off was 55.5 °C. TT was measured at 5 and 15 minutes, every 15 to 360 minutes, every 30 minutes to 8 hours, every hour to 12 hours, and at 24 hours post‐injection. Threshold data were analyzed using an anova with a repeat factor of time. Behavioral adverse effects (dysphoria) were associated with B administration, but not with HY or HY‐B administration (these produced calm euphoria). The control group was stable over time (p = 0.22) (mean threshold 40.15 °C). Overall, there was no period effect, no significant effect of administering B, but a significant effect (raised TT) of administering HY or HY‐B. If the mean value of one of the experimental groups differed from the control group (40.075 °C) by more than 2.355 °C (>42.425 °C), that mean was significantly different from control at p < 0.05 (Bonferroni's t‐tests). This occurred between 15 and 165 minutes for B, from 15 to 345 minutes for HY, and between 15 and 540 minutes for HY‐B. In this model, HY provided up to 5.75 hours of antinociception at 0.1 mg kg^?1, and concurrent administration of butorphanol (0.4 mg kg^?1) decreased the intensity of antinociception over the first 2 hours, but extended the duration of significant antinociception to about 9 hours.  相似文献   

Simondsia paradoxa: newly recorded nematode parasite from feral pigs in Australia     

DM SPRATT  PM PAVLOV 《Australian veterinary journal》1996,74(5):394-395

  相似文献   

Threonine requirements of broiler chickens: an experimental validation of a model using growth responses and carcase analysis.     

G R Barkley  I R Wallis 《British poultry science》2001,42(5):616-624

1. This paper describes the experimental testing of a model derived from an analysis of published data on the threonine requirements of broiler chickens. The model, published in a separate paper, showed that the age of the bird and dietary crude protein were highly significant determinants of threonine requirements. 2. We tested this model by measuring the threonine requirements of male broilers aged 7 to 21 d and 21 to 42 d fed on wheat-peanut meal diets containing graded concentrations of threonine. The growth of those birds given adequate threonine was compared with that of others fed a typical wheat-soyabean diet to measure the relative value of peanut meal as a protein concentrate. Finally, we measured the dry matter, nitrogen and fat concentrations in the carcase using near infrared reflectance spectroscopy (NIRS) to test the hypothesis that birds given diets deficient in an amino acid produce carcases with more fat. 3. Increasing the threonine concentration of the diet from 5.7 to 7.2 g/kg improved the growth and feed conversion ratio (FCR) of broilers. However, a further increase in dietary threonine to 7.7 g/kg had an adverse effect. The determined threonine requirement agreed with our prediction model. 4. From 7 to 21 d birds given the diet containing 7.2 g/kg threonine ate more, weighed more, had an improved FCR and, in absolute terms, had carcases with more dry matter, fat and protein than did birds given the wheat-soyabean diet. However, after correction for treatment differences in body mass there were no differences in the carcase parameters. Likewise, there were no differences in any measurements between birds given these two diets between 21 and 42 d.  相似文献   

Origin of the equine middle latency auditory evoked potential     

CB Johnson  JR Washbourne  PM Taylor 《Veterinary anaesthesia and analgesia》1995,22(1):15-18

Recordings of the middle latency of the auditory evoked potential (MLAEP) were made in eight conscious ponies. These traces were compared to those made under halothane anaesthesia with and without paralysis of the skeletal muscles. Recordings were also made from percutaneous electrodes placed along the neck with the same stimulus used for the auditory evoked potentials. The results of these experiments were used to deduce the origin of latencies in the auditory evoked potential occurring between 10 and 25 ms after the stimulus. The MLAEP was found to contain two positive peaks between the latencies of 10 and 25 ms. The first of these two peaks was not abolished by halothane anaesthesia or muscle paralysis. The second of these two peaks was abolished by halothane anaesthesia in all but one animal. In this animal the second peak was abolished by muscle paralysis. No peaks of corresponding latency were recorded from the percutaneous electrodes except from one electrode position at the caudal neck in one pony. The first peak of the middle latency auditory evoked potential seen in conscious ponies appeared to be of central nervous orign. The second peak appeared to be of muscular origin, possibly from the external auditory muscles. The second peak may be analogous to the post-auricular waveform described in man.  相似文献   

Epidemiology and financial impact of fowl cholera in turkeys: a retrospective analysis   总被引：2，自引：0，他引：2  

T E Carpenter  K P Snipes  D Wallis  R McCapes 《Avian diseases》1988,32(1):16-23

A retrospective study of the epidemiology and financial impact of fowl cholera (FC) in California meat turkeys during 1984 was performed. Data were collected from 64 flocks--23 FC-outbreak flocks and 41 controls (non-outbreak)--raised in the Central Valley of the state. Mean flock age at the time of the FC outbreak was 11.3 weeks. Flocks that reported a colibacillosis outbreak had increased odds (P = 0.11) of also having an FC outbreak. (This association may or may not indicate a cause-effect relationship.) There was no significant difference between FC-outbreak and control flocks in number of diseases reported, age at onset, or duration of diseases or syndromes except age at onset of roundheart disease. The relative mortality rates were 52% higher in FC-outbreak toms and 26% higher in FC-outbreak hens than in their controls. Medication costs were nearly tripled, and the relative condemnation rate was 60% higher in FC-outbreak flocks than in control flocks. The average costs of FC were nearly $0.40 per bird, or $18,750 per flock, in an outbreak flock of 50,000 birds, and $0.12 per bird, or $6000 per flock, in non-outbreak flocks vaccinated against FC.  相似文献   

The evaluation of a complement fixation test for the diagnosis of porcine enzootic pneumonia     

A S Wallis  G W Thompson 《The Veterinary record》1969,85(21):573-577

  相似文献   

Salmonella pathogenesis and immunity: we need effective multivalent vaccines     

Wallis TS 《Veterinary journal (London, England : 1997)》2001,161(2):104-106

  相似文献   

Effects of Spacing on Flower and Bulb Yield in the Narcissus     

A. R. Rees  J. K. A. Bleasdale  L. W. Wallis 《The Journal of Horticultural Science and Biotechnology》2013,88(2):113-120

A study was made of the effects of plant density, plant arrangement and row orientation on the yield of bulbs and flowers from small offsets of narcissus var. King Alfred left in the ground for 2 years. Over the density range of 2–14 plants per sq. ft., flower number increased from 2 to 12 per sq. ft. and stem length increased from 29 to 35 cm. Total bulb yield per unit area increased with density from 171 to 696 gm. per sq. ft.; the weights in each of four commercial bulb grades also increased. When the ratio of the between-row distance to the within-row distance was increased, bulb yield declined in E-W rows, but not in the N-S rows.  相似文献