Pre-slaughter factors linked to variation in responses to carbon dioxide gas stunning in pig abattoirs.

The stunning process is an important component of slaughter with implications for animal welfare due to the potential distress and pain in the case of a sub-effective or lengthy stun. This study examined the factors correlated with variation in responses to carbon dioxide (CO2) stunning of pigs in five Australian commercial abattoirs. A total of 1 769 pigs (199-492 focal pigs per abattoir) were individually followed from lairage to post-stunning. A standardised observation protocol was used based on a literature review of the pre-slaughter factors that may influence the reaction to CO2 stunning, such as animal background, lairage conditions, handling, stunning system and conditions. Pigs lost posture 22.5 ±â€¯0.2 s after commencement of descent of the gondola into the CO2 chamber. Latency to loss of posture was associated with farm of origin and time of day, which could be linked to various factors. Pigs that crawled or attempted to escape while in the gondola within the CO2 chamber took longer to lose posture. Crawl and escape attempts differed between abattoirs (0.6-46.2% of the pigs observed) as well as mounting other pigs (1.0-24.3%). Greater amounts of forceful contacts during handling in the race were related to more mounting in the gondola, but to less pigs crawling or attempting to escape. Mounting in the gondola was more frequent for pigs from lairage pens of mixed sexes, followed by pens of entire males and finally pens of females. Males were also twice as likely to show crawl and escape attempts than females. Gasping in the gondola was relatively frequent (63.1-81.8%) and was associated with higher activity in the lairage pen and higher skin injuries. Convulsions (60.1-69.6%) were generally observed after loss of posture. The type of CO2 system (group-wise vs single-file loading) had no significant effect on behaviour in the gondola. Nevertheless, pigs slaughtered in abattoirs with group-wise loading systems and automatic gates had lower cortisol concentrations post-stunning, which may be linked to minimal handling by stockpeople, other factors related to the systems, or differences in timing of when blood samples were taken. In conclusion, substantial variation in the reaction of pigs to CO2 stunning was observed between and within abattoirs using a uniform protocol for data collection. This variation in outcomes between abattoirs and stunning systems and the relationships between handling and behavioural outcomes indicates that improvements can be made to reduce aversive responses to CO2 stunning. In particular, avoiding mixing pigs of different sexes in lairage and aversive handling in the race may reduce aversive response to CO2 stunning.

Invasive pneumococcal disease in New Zealand 1998-2005: capsular serotypes and antimicrobial resistance.

Isolates from 3903 cases of invasive pneumococcal disease (IPD) were referred to the national reference laboratory over the 8 years, 1998-2005, as part of the laboratory-based surveillance of this disease in New Zealand. All isolates were serotyped and their antimicrobial susceptibility was tested. The incidence of IPD was highest in young children, with an average annual incidence of 100.8/100,000 in infants aged <2 years. There were changes in the prevalence of several of the serotypes during the 8-year period. Overall the seven serotypes included in the 7-valent pneumococcal conjugate vaccine, 4, 6B, 9V, 14, 18C, 19F and 23F, were the most common serotypes and accounted for 80.9% of the disease in infants aged <2 years. There was no overall change in penicillin resistance or non-susceptibility during the 8 years, and rates were 7.1% and 17.1%, respectively, in 2005. In contrast, cefotaxime and erythromycin resistance increased to reach 3.1% and 12.2%, respectively, by 2005.

A needs assessment of surgical residents as teachers.

OBJECTIVE: To determine the needs of surgical residents as teachers of clinical clerks. DESIGN: A needs assessment survey. SETTING: Department of Surgery, University of Toronto. PARTICIPANTS: Clinical clerks and surgical residents and staff surgeons. METHODS: Three stakeholder groups were defined: staff surgeons, surgical residents and clinical clerks. Focus-group sessions using the nominal group technique identified key issues from the perspectives of clerks and residents. Resulting information was used to develop needs assessment surveys, which were administered to 170 clinical clerks and 190 surgical residents. Faculty viewpoints were assessed with semi-structured interviews. Triangulation of these 3 data sources provided a balanced approach to identifying the needs of surgical residents as teachers. RESULTS: Response rates were 64% for clinical clerks and 66% for surgical residents. Five staff surgeons were interviewed. Consensus was noted among the stakeholder groups regarding the importance of staff surgeon role modelling and feedback, resident attitude, time management, knowledge of clerks' formal learning objectives, and appropriate times and locations for teaching. Discrepancies included a significant difference in opinion regarding the residents' capacity to address clerks' individual learning needs and to foster good team relationships. Residents indicated that they did not receive regular feedback regarding their teaching and that staff did not place an emphasis on their teaching role. CONCLUSIONS: This study has, from a multi-source perspective, assessed the needs of surgical residents as teachers. These needs include enhancing residents' education regarding how and what to teach medical students on a surgical rotation, and a need for staff surgeons to increase feedback to residents regarding their teaching.

Pharmaceutical transition to non-CFC pressurized metered dose inhalers.

The production of ozone-depleting chlorofluorocarbons (CFCs) was discontinued on 1 January 1996 for all uses deemed non-essential under the Montreal Protocol. However, the use of CFCs as propellants in pressurized metered dose inhalers (pMDIs) was classed as essential, providing an exemption from the agreement. Following extensive research, the hydrofluoroalkanes (HFA) 134a and 227 were identified as the only suitable replacements for CFC propellants in pMDIs. The drug delivery of pMDIs formulated with HFA 134a as a propellant and containing either salbutamol (100 microg per actuation) or fluticasone propionate (125 and 250 microg per actuation) have been assessed for dose uniformity and particle size distribution. All of the HFA 134a pMDIs delivered doses throughout the life of the canisters that were reproducible and within specified regulatory requirements. Each of the products provided an emitted dose which was within +/- 25% of the mean value indicating accurate and consistent dosing (93, 112 and 221 microg per metered dose for the salbutamol 100 microg and fluticasone propionate 125 and 250 microg HFA 134a pMDIs, respectively). These findings were unaffected by changing the storage orientation of the pMDI or by using the device in a manner designed to simulate typical patient use. The particle size distributions of HFA 134a pMDI doses did not differ significantly from those of the corresponding CFC pMDIs. As a result of the similar pharmaceutical performance, it is unnecessary to change the label claim dose of active drug when making the transition from a CFC to an HFA 134a pMDI for salbutamol (Ventolin) and fluticasone propionate (Flixotide). A seamless transition to non-CFC pMDIs will help to maintain the confidence of patients and healthcare professionals in asthma therapy.

Does PBL Matter? Relations Between Instructional Context, Learning Strategies, and Learning Outcomes.

Purpose: To compare learning strategies used in Problem based learning (PBL) and lectures, and the relations between learning strategies and learning outcomes to determine how different learning strategies associated with PBL and lectures contribute to aspects of clinical competence. Design: The 52-item learning strategies questionnaire was given to preclinical medical students during lecture and PBL sessions in first and third year from 1994 to 1998. Response patterns were compared across the two contexts and factor structures investigated. Regression analyses examined relations between learning strategies and outcomes. Main Outcome Measures/Results: Comparison of responses on the 326 complete pairs of lecture and PBL questionnaires indicated differences at the 0.05 level on 44 of the 52 items. The mean differences were greater than 0.5 (on a 5 point scale) at the 0.001 level for 20 items. Of these, five strategies were used more often in PBL and 15 in lectures. Comparisons of learning strategy use across years showed significant changes with time in both instructional contexts. Principal component analysis revealed a stable factor structure with 4 factors distinctly associated with PBL and 4 factors with the lecture learning context. The remaining 6 factors were mixed and independent of context. Exploratory regression analysis revealed that learning outcomes in examinations were influenced by learning strategies. Multiple choice performance was positively predicted by learning associated with lecture class notes and negatively by group work, whereas the OSCE (objective structured clinical exam) performance was positively predicted by class participation in PBL, self-directed note making and lecture class notes. Conclusion: We have developed a learning strategies questionnaire that shows that students' learning strategies are influenced by instructional context, and patterns of learning strategy use change over time. There is tentative evidence that the students' learning strategies influence learning outcomes.

A critical comparison of the dose delivery characteristics of four alternative inhalation devices delivering salbutamol: pressurized metered dose inhaler, Diskus inhaler, Diskhaler inhaler, and Turbuhaler inhaler.

Salbutamol is a short-acting beta 2 agonist which is effective as a rescue therapy in the treatment of asthma. This study uses in vitro test methods to compare the capability of four alternative devices to deliver an accurate and precise dose of salbutamol. It is demonstrated that the conventional metered dose inhaler (MDI) achieves excellent accuracy and precision in dose delivery. Additionally, it is the most efficient inhaler in terms of generating in-vitro a fine particle fraction from the dose. A spacer device has been shown to further enhance the dosing characteristics. When tested over a wide range of inspiratory air flow rates, the Diskus (GlaxoWellcome, Hertfordshire, UK) has comparable accuracy and precision to the MDI tested at 60 L/min, and it offers an advantage over two alternative dry powder inhalers (DPIs), delivering a more consistent dose across the range of flow rates tested and being more efficient at generating a fine particle fraction than either Turbuhaler (Astra, Lund, Sweden) or Diskhaler (GlaxoWellcome) at both 28 and 60 L/min inspiratory flow rates. Diskus, Diskhaler, Ventolin, Volumatic, and Rotadisk are trademarks of the GlaxoWellcome Group of companies. The Accuhaler is the alternative to the Diskus in those countries where the Diskus trademark is not available. Inspiryl and Turbuhaler are trademarks of the Astra Group of companies.

A demographic study of polydipsia in an institution for the intellectually disabled.

OBJECTIVE: To measure the prevalence of primary polydipsia in an Ontario institution for residents with developmental disabilities and to explore the associations of polydipsia with age, sex and level of mental retardation. METHOD: All 798 residents were screened for polydipsia using a behavioural questionnaire completed by caregivers. RESULTS: Thirty-three cases were detected: the prevalence among the mobile resident population (n = 660) was 5%. We found no association of polydipsia with age, sex, or level of mental retardation. CONCLUSIONS: Physicians should be aware of polydipsia because it is common among residents with moderate, severe, and profound mental disability. Unless screened for specifically, polydipsia may go unrecognized and may place the residents with mental handicap at risk for serious acute and chronic complications.

Screening patients with mental retardation for polydipsia.

OBJECTIVES: To determine whether caregiver responses to a screening question are a reliable method of identifying polydipsia (excessive water drinking) in institutionalized residents with mental retardation. To review the etiology, acute and chronic clinical manifestations, and care of polydipsia and water intoxication. METHOD: This paper presents an assessment of interrater reliability for a screening question for polydipsia using responses of primary caregivers of preidentified polydipsia cases (n = 32) and matched controls (n = 33) in a large Canadian institution for developmentally handicapped adults. A chart review of all cases of identified water intoxication is also provided. The behavioural outcomes of preventive measures for water intoxication are described. RESULTS: The screening instrument was reliable, having a kappa (interrater reliability) of 0.73. Several case descriptions illustrate typical presentations of water intoxication in this population. CONCLUSIONS: Polydipsia is reliably identified by caregiver responses to a screening question. It should be screened for regularly to ensure appropriate care to prevent important acute and chronic complications.

Analysis of remote reflection spectroscopy to monitor plant health.

Remote non-contact reflection spectroscopy is examined as a method for detecting stress in Controlled Ecological Life Support System CELSS type crops. Lettuce (Lactuca [correction of Latuca] Sativa L. cv. Waldmans Green) and wheat (Triticum Aestivum L. cv. Yecora Rojo) were grown hydroponically. Copper and zinc treatments provided toxic conditions. Nitrogen, phosphorous, and potassium treatments were used for deficiency conditions. Water stress was also induced in test plants. Reflectance spectra were obtained in the visible and near infrared (400nm to 2600nm) wavebands. Numerous effects of stress conditions can be observed in the collected spectra and this technique appears to have promise as a remote monitor of plant health, but significant research remains to be conducted to realize the promise.

Responses of albino and hooded rats to various illumination choices in a six-chambered alleyway.

To determine preferred illumination when multiple choices were simultaneously available, 10 different levels of illuminance (including darkness) were grouped into three overlapping ranges, each composed of six different choices. Subjects were permitted to move freely among six chambers in an enclosed alleyway for 48 continuous hours. Entries and duration in each of the chambers served as the dependent variables. Five groups of seven animals each were tested. Hooded rats preferred darkness, 0.01 ft-c (0.11 lx) and 20 ft-c (215.2 lx) about equally; each albino group preferred the dimmest available illuminated choice, viz., 0.01 ft-c (0.11 lx), 0.1 ft-c (1.08 lx), and 1.0 ft-c (10.76 lx); control rats distributed their time equally among all chambers. Activity of all groups reflected a typical circadian rhythm. These relative preferences for illumination contrast with absolute preference previously reported and perhaps reflect methodological differences.

The significance of laryngeal edema following radiotherapy of carcinoma of the vocal cord.

Laryngeal edema persisting for more than three months following radiotherapy developed in 38 of 247 (15.4%) patients irradiated for carcinoma of the vocal cord. In 17 (44.7%) of these patients, the laryngeal edema was associated with persistent or recurrent disease, although only 25.4% of the patients with uncontrolled disease had laryngeal edema. The incidence of laryngeal edema was 13.1% for T1 disease, 23.8% for T2, and 21.4% for T3 and T4 disease. It increased significantly with increase of minimum tumor dose greater than or equal to 7000 rads or with NSD greater than 1900 ret, being 46.2% with minimum tumor dose greater than or equal to 7000 rad and 13.7% with minimum tumor dose less than 7000 rad and 43% with NSD greater than 1900 ret and 17% with NSD less than or equal to 1900 ret. It also increased with increase of field size, being 13.4% with field sizes less than 6.0 x 6.0 cm2, and 24.4% with field sizes greater than or equal to 6.0 x 6.0 cm2. When laryngeal edema is progressive and unresponsive to conservative measures, multiple biopsies should be performed to establish the presence of persistent or recurrent disease before salvage surgery is attempted. However, if it is mild, stable, no visible recurrence develops, and especially if it is limited to the arytenoids, no biopsy should be attempted because of the risk of inducing laryngeal necrosis.

Analysis of the anti-coccidial drug, halofuginone, in chicken tissue and chicken feed using high-performance liquid chromatography.

Methods are described for the analysis of the anti-coccidial drug, halofuginone, in chicken tissue at concentrations as low as 1 ppb (0.001 ppm) and in chicken feed at a concentration of 3 ppm, using high-performance liquid chromatography. The tissue analysis involves: enzymatic release of the halofuginone followed by ethyl acetate extraction under basic conditions, partition into ammonium acetate buffer, concentration using Sep-pakTM C18 cartridge. The feed analysis involves: ethyl acetate extraction under basic conditions, partition into hydrochloric acid, concentration using XAD-2 column chromatography. Both methods use high-performance liquid chromatography with ultraviolet detection for the final analysis. Precision and accuracy data for both methods are given.

Treatment of carcinoma of the vocal cord. A review of 20 years experience.

At the University of California, San Francisco, 323 patients were treated for carcinoma of the vocal cord between January 1956 and December 1975. Patients with early T1 or T2 lesions were treated with radiotherapy or conservative surgery. Patients with T3 or T4 lesions were treated with total laryngectomy, radiation alone, or combined therapy. Of the 247 patients treated with definitive radiotherapy, initial control of the primary lesion was achieved in 100% of T1S, 80% of T1, 52% of T2, and 50% of T3 and T4 lesions. Surgical salvage of radiation failures was 86%, giving ultimate control rates in this group of 100% for T1S, 97% for T1, 91% for T2 and 64% for T3 and T4. Involvement of the anterior commissure did not significantly affect local control or survival rates of the irradiated patients. Voice quality was satisfactory in 95% of controlled patients. Surgery alone was used as the primary treatment modality in 63 patients, with ultimate local control achieved in 75% of T1S, 83% of T1, 85% of T2, 81% of T3 and T4 lesions. Planned combined therapy was successful in 9/13 patients in whom it was used. The overall 3 and 5 year actuarial survival rates were 84% and 77% respectively corresponding determinate survival rates were 90% and 86%.

The distribution excretion and biotransformation of p-dichloro[14C]benzene in rats after repeated inhalation, oral and subcutaneous doses.

1. Following repeated daily whole-body exposure (3 h/day) of rats to atmospheres containing p-dichloro[14C]benzene (10000p.p.m.), or administration of oral or subcutaenous doses (250 mg/kg/day), 24-h tissue concn. of 14C were similar and did not increase after six days dosing, but tended to decrease. 2. After repeated daily atmospheric exposures or oral doses, highest concn. of 14C occurred in fat, kidneys, liver and lungs. Concn. declined rapidly to near or below limits of detection (less than 0.2 p.p.m.) in plasma and tissues at 5 days. After similar subcutaneous doses, tissue concn. declined more slowly. 3. During five days after repeated dosing, most excreted 14C (91-97%) was in the urine. Little was excreted in faeces or expired air. Excretion was more prolonged following subcutaneous administration. After single doses to bile duct-cannulated animals, 46-63% of the excreted 14C was in the bile during 24 h. 4. The pattern of metabolites in urine and bile was similar after each route of administration although there were quantitative differences. Urine extracts contained two major 14C-components, namely a sulphate and a glucuronide of 2,5-dichlorophenol, representing 46-54% and 31-34% of the urinary 14C respectively. Two minor components were identified by mass spectrometry as a dihydroxydichlorobenzene and a mercapturic acid of p-dichlorobenzene. 5. The glucuronide of 2,5-dichlorphenol was the major 14C component in bile (30-42%).

Analysis of the anti-coccidial drug, halofunginone, in chicken feed using gas-liquid chromatography and high-performance liquid chromatography.

Methods are described for the analysis of the anti-coccidial drug, halofuginone, at concentrations of 3 ppm in chicken feed, using gas-liquid chromatography and high-performance liquid chromatography. Both methods are based on ethyl acetate extraction, partition into hydrochloric acid and purification and concentration using XAD-2 column chromatography. The precision and accuracy of both methods is given.

Ecophysiological studies of Sonoran Desert plants : IV. Seasonal photosynthetic capacities of Acacia greggii and Cercidium microphyllum.

The gas exchange and water relations of two Sonoran Desert plants were measured throughout a 12 month period. Seasonal photosynthesis patterns of both species followed the seasonal variation in soil and plant water potential. Acacia greggii, a winter deciduous shrub, appears to be fall active since the day-long mean photosynthesis rate was maximum, i.e., 16 mg CO2 dm-2 h-1, at this time. Cercidium microphyllum, a drought deciduous and chlorophyllous-stemmed tree, also appears to be mainly fall active. For this species the day-long mean photosynthesis rate was not in excess of 14 mg CO2 dm-2 h-1. Both species initiate leaf production in the spring and neither experiences severe plant water stress. Seasonal minima of dawn plant water potential were-44 and-32 bars for the shrub and tree species, respectively. The two species differ slightly in their tolerance of heat and water stress, since foliated plants of Acacia greggii maintain summer gross photosynthesis.All of the aboveground organs for plants of C. microphyllum are capable of exogenous 14CO2 assimilation. This species appears to be unique in the magnitude of the photosynthetic production contributed by stems. Seasonal production by stems, leaves and flowers/fruits averaged 72, 24 and 4% of the total carbon gain per tree, respectively. Aboveground gross primary production was over 4.5-fold greater than aboveground net primary production. This difference between these two production estimates is likely due to the very small foliar biomass maintained throughout the year and the energy expenditure required to maintain the metabolically active cells of the chlorophyllous stems.

Ecophysiological studies of Sonoran Desert plants : III. The daily course of photosynthesis for Acacia greggii and Cercidium microphyllum.

The gas exchange and water relations of two Sonoran Desert plants are compared during contrasting periods of water and heat stress. Photosynthesis of Acacia greggii, a winter deciduous shrub, and Cercidium microphyllum, a chlorophyllous stemmed tree, show a moderate correlation with dawn plant water potential. For both species a relationship between stomatal conductance and dawn plant water potential was not apparent, although A. greggii demonstrated a greater overall stomatal conductance. This affected a greater daytime decrease in plant water potential at all levels of water stress and suggests A. greggii is less sensitive to water stress. Our results suggest the lower limit for gross photosynthesis occurs when dawn plant water potentials are less than -44 and -31 bars for the shrub and tree species, respectively. During periods of extreme water and heat stress the photosynthetic capacity of both species is regulated more by mesophyll than stomatal conductance. However, partial stomatal closure causes plant water potential to increase during the day and exceed dawn values. During periods of minimal water and heat stress the daily course of photosynthesis parallels the change in stomatal conductance and irradiance. Maximum gross photosynthesis rates are nearly three-fold higher than the rates observed during periods of stress, with those of A. greggii generally greater than the rates observed in plants of C. microphyllum.