bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oscillations in large mammal populations: are they related to predation or rainfall?
Authors: Ogutu Joseph O. , Owen‐Smith Norman 
Published: January 2006

AbstractCyclic population dynamics is relatively common among populations of small mammals in high latitudes but is not yet established among African savanna ungulates. However, oscillations may be expected in large mammal populations subject to quasi‐periodic oscillations in regional rainfall. We evaluated evidence for environmentally entrained oscillations in a large‐mammal predator–prey system in Kruger National Park (KNP), South Africa, where rainfall exhibits quasi‐periodic oscillations. The evaluation is based on analysis of comparative changes in the abundance of twelve ungulate species throughout South Africa's KNP using population counts over the period 1965–1996. We present evidence suggesting that (i) twelve ungulate populations display cyclic variability with half‐periods ranging between 10 and 18 years, (ii) this variability was associated with lagged rainfall between 3 and 10 years back in the past for different ungulate species, and (iii) the ungulate species respond in contrasting ways to rainfall, with some reaching highest abundance during periods of low rainfall and others under conditions of high rainfall. These findings are not consistent with the response pattern we would expect if the population oscillations were driven directly by the rainfall influence on food availability. Instead they seem to be an outcome of predator–prey interactions, which are entrained by the effect of rainfall on habitat conditions affecting the relative susceptibility of the different ungulate species to predation.
The suitability of the degradation gradient method in arid Namibia
Authors: Getzin Stephan 
Published: January 2006

AbstractThe Degradation Gradient Method (DGM) is a sophisticated technique for the assessment of range condition. It applies multivariate analyses of herbaceous species data to detect subtle degrees of overgrazing. The suitability of this multivariate method was tested in the central Highland Savanna of Namibia by comparing its results against a univariate analysis of herbaceous data in a simple but robust Range‐Unit Model. Despite aridity and topographical heterogeneity, the DGM performed unexpectedly well under these conditions. The relative instability of this dry savanna system favoured the applicability of the DGM by promoting a clear grazing gradient. Using species density data only resulted in an incorrect outcome of the multivariate analysis. The sensitivity of the DGM could be improved by combining density and cover data.
Estimating the density of kudu (Tragelaphus strepsiceros) in subtropical thicket using line transect surveys of dung and DISTANCE software
Authors: Ellis Amanda M. , Bernard Richard T. F. 
Published: January 2006

AbstractMany ecotourism reserves in the Eastern Cape Province of South Africa have introduced large carnivores which prey on ungulates such as kudu. Kudu occupy thick vegetation and helicopter‐based counts are not appropriate. In this study we tested line transect counts of faecal pellets in conjunction with DISTANCE analysis as a method for assessing the abundance of kudu. Transects were undertaken in three regions of two game reserves and the results compared with helicopter based game counts (for two regions) and a known kudu population in the third region (an enclosed breeding centre). Estimates of kudu abundance were two to three times greater than the helicopter counts, but within the known number of kudu in the breeding centre. The increased accuracy in the breeding centre was probably because the transects covered a greater percentage of the available habitat (0.07%) than in the reserves (approximately 0.007%). We suggest that DISTANCE software and line transects counts of pellet groups can be used for kudu and probably for other ungulates in thicket‐type vegetations. Accuracy will depend on the percentage of the available habitat that is surveyed and on the accuracy of the defecation and decay rates.
Landscape heterogeneity and the use of space by elephants in the Kruger National Park, South Africa
Authors: Grainger Matthew , van Aarde Rudi , Whyte Ian 
Published: January 2006

AbstractLandscape heterogeneity may influence ranging behaviour of mammals. Here we relate the home range size of elephants living in the Kruger National Park to the number of patches, proportion of each patch, spatial arrangement of patches, patch shape, and contrast between neighbouring patches. Home range sizes decreased exponentially with an increase in the number of patches per 100 km2 and the home range sizes of bulls were in general more strongly related to measures of heterogeneity. This may reflect differences in perception of heterogeneity between the sexes.
A telemetry‐based study of bushbuck (Tragelaphus scriptus) home range in Valley Bushveld
Authors: Coates Gregory D. , Downs Colleen T. 
Published: January 2006

AbstractWith the aid of radio‐telemetry, bushbuck home range was investigated to determine total home range size, home range utilization and home range overlap for the summer season. Estimates of total home range size for males using minimum convex polygons (MCPs) and fixed kernels (FKs) were 33.9 and 32.1 ha, respectively. Estimates of total home range size for females using MCPs and FKs were 12.0 and 13.5 ha, respectively. A significant difference between total home range sizes for male and female was found but there was no significant difference for age (adult and subadult). Female bushbuck home range size was compared to that expected from the published allometric relationship for the scaling of home range area on body mass, where the study animals appeared to have home ranges of half of that predicted. Bushbuck typically utilized one core area within their home ranges in which 50% of their time was spent in approximately 17.0% and 11.7% of their total home range for males and females, respectively. A substantial overlap in total home range and core areas between animals was found.
Ecological impact of tobacco farming in miombo woodlands of Urambo District, Tanzania
Authors: Mangora Mwita M. 
Published: January 2006

AbstractThis paper examines the ecological threat of tobacco farming in Urambo District, the leading producer of flue‐cured tobacco in Tanzania with other major producers being Tabora, Iringa and Chunya Districts. Structured interviews were conducted in four villages while 39 Modified‐Whittacker plots were laid in tobacco fallow lands for inventory of woody species to ascertain ecological performance and the impact of tobacco on species diversity, richness and standing stock functions. There was higher than expected species richness with a total of 115 tree and shrub species identified. Tobacco farming showed no significant negative effect on the floristic composition and stem density. However, the significantly reduced biomass and change in vegetation structure illustrate the potential loss in ecological function of the woodlands. Land clearing for tobacco planting account to an annual deforestation of 3.5% while on average a farmer requires 23 m3 of stacked wood only for curing per season which adds another 3% of deforestation. Shifting cultivation is no longer sustainable given the shortened fallow periods of 4 years. Improved barn structures, alternative sources of fuel like coal, tree planting, mixed cropping and cash crops that are environment friendly are recommended for ecological restoration.
Minimum local anaesthetic dose (MLAD) of intrathecal levobupivacaine and ropivacaine for Caesarean section*
Authors: Parpaglioni R. , Frigo M. G. , Lemma A. , Sebastiani M. , Barbati G. , Celleno D. 
Published: January 2006

SummaryWe determined the minimum local anaesthetic dose (MLAD) of spinal levobupivacaine and ropivacaine for Caesarean section. Ninety women were randomly allocated to two groups and received 3 ml of study solution by a combined spinal/epidural technique. The initial dose was 12 mg for levobupivacaine and 17 mg for ropivacaine groups. To be considered effective, a test solution had to achieve a visual analogue pain score (VAPS) of 30 mm or less at skin incision, uterine incision, birth, peritoneal closure, and at the end of surgery. Effective or ineffective responses determined, respectively, a 0.3 mg decrease or increase of the same drug for the next patient in the same group, using up–down sequential allocation. The MLAD of levobupivacaine was 10.58 mg (CI 95%: 10.08–11.09) and the MLAD of ropivacaine 14.22 mg (CI 95%: 13.67–14.77), using the Dixon and Massey formula. The potency ratio between spinal levobupivacaine and spinal ropivacaine was 1.34.
Study of a combined percutaneous local anaesthetic and the TDS® system for venepuncture
Authors: Tucker A. T. , Chik Z. , Michaels L. , Kirby K. , Seed M. P. , Johnston A. , Alam C. A. S. 
Published: January 2006

SummaryTransdermal Delivery System (TDS®) is a liquid formulation which can be applied to the skin via a metered pump spray to deliver drug across skin. This placebo controlled, double blind trial compared anaesthetic properties of two TDS® systems (TDS®α and TDS®β) with placebo. The active and placebo treatments were applied to the dorsum of the hands, bilaterally and simultaneously for 5 min on 100 healthy volunteers. Following cannulation, pain perception was measured using the verbal rating score (VRS) and visual analogue score (VAS). Lidocaine plasma levels were assessed at 0 and 2 h. The VRS and VAS results show that TDS®β significantly decreased pain score compared to placebo (p < 0.02). Blood lidocaine at 2 h post application was also higher for TDS®β than for TDS®α, suggesting that a 5 min application of TDS®β was effective in delivering local anaesthetic and accelerating the onset of skin anaesthesia prior to venous cannulation in adults.
The effect of gel lubrication on cuff leakage of double lumen tubes during thoracic surgery*
Authors: Sanjay P. S. , Miller S. A. , Corry P. R. , Russell G. N. , Pennefather S. H. 
Published: January 2006

SummaryHigh‐volume, low‐pressure tracheal cuffs of disposable double lumen tubes may offer limited protection to the dependent lung if fluid leaks through folds in the inflated cuffs. This study was undertaken to determine the incidence of fluid leakage past the tracheal cuff and whether gel lubrication reduces the incidence. Fifty‐five patients were randomly assigned to receive a double lumen tube with or without gel lubrication. The dependent lung was intubated. With the patient in the lateral position, methylthionium chloride was administered above the tracheal cuff via a pre‐attached catheter. Fibreoptic bronchoscopy was performed to determine if dye had passed the tracheal cuff. Three patients were excluded. Dye leakage was seen in 12/27 and 3/25 patients in the unlubricated and lubricated group, respectively (p = 0.014). Gel lubrication significantly reduces fluid leakage past the tracheal cuff of a double lumen tube and should be considered for all thoracic surgical patients requiring one‐lung ventilation.
A comparison of the Soft Seal™ disposable and the Classic re‐usable laryngeal mask airway*
Authors: Shafik M. T. , Bahlman B. U. , Hall J. E. , Ali M. S. 
Published: January 2006

SummaryMany new supraglottic airway devices have been recently introduced, their development motivated by the need for a single‐use equivalent to the original re‐usable laryngeal mask airway. We performed a randomised cross‐over study in spontaneously breathing patients comparing the re‐usable Laryngeal Mask Airway‐Classic (LMA™) and the disposable Soft Seal Laryngeal Mask in sizes 3, 4 and 5. Sixty patients had an LMA and a disposable laryngeal mask placed in random order. The primary outcome was first attempt insertion success rate. Ease of insertion was similar in both groups and there was no difference in first attempt success rates (96% with LMA and 92% with disposable laryngeal mask). The disposable laryngeal mask required significantly less air to inflate the cuff to produce a seal (10 [10–25] ml with disposable laryngeal mask and 15 [10–30] ml with laryngeal mask) and the cuff pressure produced was significantly lower (35 [20–80] cmH2O with disposable laryngeal mask and 75 [20–120] cmH2O with LMA). Data are median and range. We conclude that the disposable laryngeal mask is an acceptable alternative to the re‐usable LMA.
Liver enzyme induction and inhibition: implications for anaesthesia
Authors: Sweeney B. P. , Bromilow J. 
Published: January 2006

SummaryRecent breakthroughs in molecular biology have enabled a reclassification of drug metabolising enzymes based on their amino acid sequence. This has led to a better understanding of drug metabolism and drug interactions. The majority of these drug metabolising enzymes may be either induced or inhibited by drugs or by extraneous substances including foodstuffs, cigarette smoke and environmental pollutants. Virtually all drugs used in anaesthesia are metabolised by either hepatic phase 1 or phase II enzymes. This review considers the classification of drug metabolising enzymes, explains the mechanisms of enzyme induction and inhibition, and also considers how the action of drugs commonly used by anaesthetists, including opioids and neuromuscular blocking drugs, may be altered by this mechanism.
Postoperative pain, nausea and vomiting following paediatric day‐case tonsillectomy
Authors: Ewah B. N. , Robb P. J. , Raw M. 
Published: January 2006

SummaryMore than 30% of all surgical activity for children in England and Wales is accounted for by routine ENT operations. There is known to be a high incidence of postoperative pain, nausea and vomiting following paediatric tonsillectomy with or without adenoidectomy. This prospective study examined the incidence of these complications in 100 children admitted for routine, elective day‐case tonsillectomy, with or without adenoidectomy. The children were anaesthetised in accordance with our standard paediatric day‐case protocol. The incidence of vomiting on the day of surgery was significantly less in the group anaesthetised in accordance with the protocol, compared to those in previously published studies. Postoperative pain was well controlled, with 88% of the children having minimal pain on the day of surgery, and reporting a pain score of 0–2. Modifying the anaesthetic care to a protocol designed to reduce postoperative pain, nausea and vomiting achieved measurable improvements in the recovery of this group following surgery. It has enabled us to evolve from a 100% inpatient stay for these operations to 98% day‐case discharge rate, with minimal post anaesthetic or surgical morbidity. We describe the protocol and discuss the implications of implementing such a protocol for children undergoing these common operations.
Haemodynamic effects of the prone position: a comparison of propofol total intravenous and inhalation anaesthesia
Authors: Sudheer P. S. , Logan S. W. , Ateleanu B. , Hall J. E. 
Published: January 2006

SummaryThe haemodynamic changes of the prone position were investigated in 40 ASA I–II patients undergoing lumbar spine surgery. Patients were randomly assigned, following propofol intravenous induction, to receive maintenance of anaesthesia using either isoflurane 1–1.2% in air or target controlled propofol 3 μg.ml−1 infusion. Measurements of non‐invasive blood pressure, heart rate and cardiac output were made in the supine position. The patient was then turned prone onto a Montreal pattern mattress and measurements repeated. Cardiac output measurements were made using a non‐invasive cardiac output monitor. We found a significant reduction in cardiac index in both groups and a significantly greater change with propofol compared to isoflurane on turning supine to prone (CI change 0.4 vs 0.7 l.min−1.m−2 p = 0.001 and SVRI change 89 vs 177 dyne.s−1.cm−5, p = 0.041). We conclude that turning healthy patients prone produces a clinically significant reduction in cardiac output, the change being greater during maintenance of anaesthesia using propofol compared to isoflurane.
A comparison of two single dilator percutaneous tracheostomy sets: the Blue Rhino™ and the Ultraperc™
Authors: Patel P. B. , Ferguson C. , Patel A. 
Published: January 2006

SummaryThe single tapered dilator kit is the most commonly used percutaneous tracheostomy set in the UK. The Cook Blue Rhino™ and the Portex Ultraperc™ were compared in the laboratory on mannequin and porcine airway models. The following data were collected: the subjective ease of dilating the trachea and inserting the tracheostomy tube; the time taken and the anterior–posterior compression during dilatation and tube insertion; the incidence and extent of posterior tracheal wall damage. During dilatation, the Blue Rhino™ caused less mean percentage anterior–posterior compression (34.8% vs. 51.5%, p = 0.0014). There was no difference in subjective ease or time for dilatation in either mannequin or porcine airway models. During insertion of the tracheostomy tube, the Ultraperc™ was subjectively easier in the porcine airway model (p = 0.001); had a shorter median insertion time in both the mannequin (3 s vs. 7.2 s, p = 0.0006) and the porcine airway model (4.3 s vs. 8.5 s, p = 0.0005); the mean percentage anterior–posterior compression caused was less in the mannequin (51.5% vs. 76%, p = 0.0008). The overall incidence of posterior wall damage was 65% with 25% having deep lacerations. There was no difference in the incidence of damage between the two sets. The Ultraperc™ therefore has advantages during tracheostomy tube insertion that are statistically and clinically significant. The advantages are probably due to the presence of the tracheostomy tube introducer.
Ruptured splenic artery aneurysm in pregnancy presenting in a manner similar to pulmonary embolus
Authors: Richardson A. J. , Bahlool S. , Knight J. 
Published: January 2006

SummaryWe report a patient, 33 weeks pregnant with twins, who sustained a ruptured splenic artery aneurysm. This presented with left sided chest pain, breathlessness, low oxygen saturations and electrocardiogram (ECG) changes supportive of a diagnosis of massive pulmonary embolus. The diagnosis of splenic artery rupture was made at emergency Caesarean section performed for fetal distress.
Visualisation of needle position using ultrasonography
Authors: Chapman G. A. , Johnson D. , Bodenham A. R. 
Published: January 2006

SummaryAnaesthetists and intensivists spend a considerable proportion of their working time inserting needles and catheters into patients. In order to access deeper structures like central veins and nerves, they have traditionally relied on surface markings to guide the needle into the correct position. However, patients may present challenges due to anatomical abnormalities and size. Irrespective of the skill of the operator, there is the ever‐present risk of needle misplacement with the potential of damage to structures like arteries, nerve bundles and pleura. Repeated attempts, even if ultimately successful, cause patient suffering and probably increase the risk of infection and other long term complications.Portable and affordable, high‐resolution ultrasound scanners, has accelerated the interest in the use of ultrasound guidance for interventional procedures. Ultrasound guidance offers several advantages including a greater likelihood of success, fewer complications and less time spent on the procedure. Even if the target structure is identified correctly there is still the challenge to place the needle or other devices in the optimum site. The smaller and deeper the target, the greater the challenge and potential usefulness of ultrasound guidance.As a result of limited training in the use of ultrasound we believe that many clinicians fail to use it to its full potential. A lack of understanding, with regard to imaging the location of the needle tip remains a major obstacle. Needle visualisation and related topics form the basis for this review.
Learnability and discriminability of melodic medical equipment alarms*
Authors: Sanderson P. M. , Wee A. , Lacherez P. 
Published: January 2006

SummaryMelodic alarms proposed in the IEC 60601‐1‐8 standard for medical electrical equipment were tested for learnability and discriminability. Thirty‐three non‐anaesthetist participants learned the alarms over two sessions of practice, with or without mnemonics suggested in the standard. Fewer than 30% of participants could identify the alarms with 100% accuracy at the end of practice. Confusions persisted between pairs of alarms, especially if mnemonics were used during learning (p = 0.011). Participants responded faster (p < 0.00001) and more accurately (p = 0.002) to medium priority alarms than to high priority alarms, even though they rated the high priority alarms as sounding more urgent (p < 0.00001). Participants with at least 1 year of formal musical training identified the alarms more accurately (p = 0.0002) than musically untrained participants, and found the task easier overall (p < 0.00001). More intensive studies of the IEC 60601‐1‐8 alarms are needed for their effectiveness to be determined.
Pre‐operative detection of valvular heart disease by anaesthetists
Authors: Van Klei W. A. , Kalkman C. J. , Tolsma M. , Rutten C. L. G. , Moons K. G. M. 
Published: January 2006

SummaryWe prospectively estimated the prevalence of heart murmurs in 2522 consecutive adult non‐cardiac surgery patients during pre‐operative evaluation. Factors that contribute to the detection of a heart murmur were identified, and echocardiography was used to evaluate to what extent a murmur reflected presence of valvular heart disease. A cardiac murmur was detected in 106 patients (prevalence 4.2%, 95% CI: 3.5–5.1%). Multivariable logistic regression analyses showed that age and general physical impression were independently associated with detecting a murmur (p‐values < 0.01). In 83 (79%) of the patients with a murmur, an echocardiographic diagnosis was available: 39% had aortic valve abnormalities, 24% had mitral valve regurgitation, 7% had other valvular heart disease and 30% did not have any abnormality. Thus, 58 of the 83 patients had valvular heart disease (positive predictive value using routine cardiac auscultation for diagnosing VHD: 70%, 95% CI: 59–79%). Murmurs in patients younger than 40 years never reflected valvular heart disease. Pre‐operative cardiac auscultation seems only reasonable in patients aged 40 years or older. Subsequent echocardiography in these selected patients is necessary.