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Background: The addition of calcium to resuscitation fluids is a common practice in horses, but studies evaluating the effects of calcium supplementation are limited. In healthy horses, decreases in heart rate and changes in serum electrolyte concentrations have been reported. Hypothesis: Calcium gluconate administration at a rate of 0.4 mg/kg/min to eliminated endurance horses with metabolic problems will affect heart rate, gastrointestinal sounds, and serum electrolyte concentrations. Animals: Endurance horses eliminated from the Tevis Cup 100‐mile (160 km) endurance ride for metabolic problems and requiring IV fluid therapy were eligible. Methods: Sixteen horses were randomly assigned to receive 0.4 mg/kg/min of calcium (23% calcium gluconate solution) over 1 hour diluted in 10 L of a non‐calcium containing isotonic crystalloid (CAL group) or 10 L of a non‐calcium containing isotonic crystalloid (CON group). Staff members administering the fluids were blinded to treatment group. Blood samples were collected and physical examinations performed before and after treatment. Heart rates were recorded every 15 min during fluid administration. Data were compared using 2‐way analysis of variance (ANOVA) with repeated measures for continuous variables and Fisher's exact test for categorical variables. Results: Calcium was associated with lower heart rates 45 min after starting the infusion (P =.002). Gastrointestinal sounds were less likely to improve in the calcium group compared with the control group (P =.005). An increase in plasma phosphorus concentration (P =.03) was associated with calcium administration. Conclusions: Intravenous calcium supplementation to endurance horses eliminated from competition after development of metabolic problems may decrease heart rate but impairs improvement in gastrointestinal sounds. [ABSTRACT FROM AUTHOR]

Summary: An adult Quarter Horse gelding (Case 1) was evaluated for tachypnoea and acute dysphagia. A 20‐year‐old Quarter Horse gelding (Case 2) was evaluated for respiratory stertor and severe, acute swelling of the head in the submandibular region. A physical examination, complete blood count, blood chemistry, upper airway endoscopy, and peripheral blood Anaplasma phagocytophilum polymerase chain reaction were completed for both horses. Both horses tested positive for A. phagocytophilum. The upper airway endoscopy for Case 1 revealed a feed contaminated pharynx, absent swallowing reflex, and left laryngeal hemiplagia. The upper airway endoscopy for Case 2 revealed severe diffuse pharyngeal swelling occluding the airway. Due to increased respiratory effort in Case 2, a tracheotomy was performed. In both horses, treatment consisted of intravenous oxytetracycline 6.6 mg/kg bwt i.v. q. 24 h for 2–3 days followed by minocycline 4 mg/kg bwt per os q. 12 h for 10–14 days. Both horses made full recoveries. [ABSTRACT FROM AUTHOR]

Background: Trauma from dog attacks has been associated with mortality rates as high as 23% in some species. However, the prognosis and clinical features of this type of injury have not been described in equids. Hypotheses/Objectives: To describe survival rate, signalment, clinical features, and biochemical results in equids presented for emergency care after presumed dog attacks. We hypothesized there would be differences between survivors and nonsurvivors. Animals A total of 28 equids presented for presumed dog attacks from 3 referral centers. Methods: A retrospective study was performed using data from 3 hospitals between 2008 and 2016. Survival was defined as survival at 14 days postdischarge. Variables were compared between survivors and nonsurvivors using a t test, Mann‐Whitney U test, or Fisher's exact test as appropriate. Results: Overall mortality rate was 21%. Ponies and miniature horses represented 16/28 (57%) of the animals in the study. Full‐sized equids had a lower risk of nonsurvival as compared to smaller patients (odds ratio = 0.02; 95% confidence intervals = 0.00‐0.27; P <.005). Animals with lower body temperatures had increased risk for nonsurvival (P =.0004). Increased admission blood lactate concentrations (P =.003) and decreased serum total protein concentrations (P =.006) were associated with nonsurvival. Conclusions: The mortality rate in equids attacked by dogs was similar to what is reported for other veterinary species. Smaller equids and those with increased admission blood lactate concentration, lower body temperature, and lower total serum protein concentrations were less likely to survive. [ABSTRACT FROM AUTHOR]

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We conducted a survey and semi-structured qualitative interviews to investigate current anaesthetic practice for arteriovenous fistula formation surgery in the UK. Responses were received from 39 out of 59 vascular centres where arteriovenous access surgery is performed, a response rate of 66%. Thirty-five centres reported routine use of brachial plexus blocks, but variation in anaesthetic skill-mix and practice were observed. Interviews were conducted with 19 clinicians from 10 NHS Trusts including anaesthetists, vascular access and renal nurses, surgeons and nephrologists. Thematic analysis identified five key findings: (1) current anaesthetic practice showed that centres could be classified as 'regional anaesthesia dominant' or 'local anaesthesia/mixed'; (2) decision making around mode of anaesthesia highlighted the key role of surgeons as frontline decision makers across both centre types; (3) perceived barriers and facilitators of regional block use included clinicians' beliefs and preferences, resource considerations and patients' treatment preferences; (4) anaesthetists' preference for supraclavicular blocks emerged, alongside acknowledgement of varied practice; (5) there was widespread support for a future randomised controlled trial, although clinician equipoise issues and logistical/resource-related concerns were viewed as potential challenges. The use of regional anaesthesia for arteriovenous fistula formation in the UK is varied and influenced by a multitude of factors. Despite the availability of anaesthetists capable of performing regional blocks, there are other limiting factors that influence the routine use of this technique. The study also highlighted the perceived need for a large multicentre, randomised controlled trial to provide an evidence base to inform current practice. [ABSTRACT FROM AUTHOR]

The Drummond Basin of central Queensland preserves a large-volume succession of little studied, predominantly fluviatile, coarse-grained sedimentary rocks of mid-Mississippian age. The stratigraphy of the basin has been subdivided into three sedimentary cycles. The Cycle 1/Cycle 2 boundary records a distinct, but poorly understood change in provenance from a volcanic-dominated succession related to initial basin rifting (Cycle 1) to a quartz-rich, craton-derived succession (Cycle 2). Cycle 3 has been thought to mark a resumption of intrabasinal volcanism and related sedimentation. The purpose of this study was to enhance the understanding of the basin-wide siliciclastic sedimentation of Cycles 2 and 3, and causes for the changes in sediment provenance. This objective was achieved by constraining large-scale spatial and temporal depositional trends and investigating sediment transport pathways into and through the basin. Petrographic, QFL, paleocurrent and conglomerate clast analyses were undertaken. The observations presented here have several implications relevant to understanding the stratigraphy of the Drummond Basin and regional tectonic events at this time. Cycle 3 is revised here primarily to be a continuation of Cycle 2-style basement-derived sedimentation, rather than recording a resumption of volcanism in the area, as per prevailing models. Quartz-rich sedimentation in the Drummond Basin was, therefore, more long-lived than previously envisaged, and once established, was not significantly disrupted by volcanism. Cycle 2 formation thicknesses appear highly variable across the basin. This is unlikely to be a result of pre-existing rift-related topography as suggested in previous models. The thickness variations are more likely related to sediment bypassing and post-depositional deformation in the area. The distinctive coarse-grained, relatively quartz-rich sedimentation of Cycles 2 and 3 is unusual in its volume and extent. The sediment was transported into the basin from its southern/southwestern margin, implying long-distance transport and extrabasinal sediment supply. While the specific source terrain(s) remain unknown, one plausible tectonic driver was far-field influence of the intraplate Alice Springs Orogeny. [ABSTRACT FROM AUTHOR]

Summary: Background: Emerging experimental evidence suggests that air pollution may contribute to development of obesity and diabetes, but studies of children are limited. Objectives: We hypothesized that pollution effects would be magnified after bariatric surgery for treatment of obesity, reducing benefits of surgery. Methods: In 75 obese adolescents, excess weight loss (EWL), high‐density lipoprotein (HDL) cholesterol, triglycerides, alkaline phosphatase (ALP) and hemoglobin A1c (HbA1c) were measured prospectively at baseline and following laparoscopic adjustable gastric banding (LAGB). Residential distances to major roads and the average two‐year follow‐up exposure to particulate matter <2.5 μm (PM2.5), nitrogen dioxide (NO2) and ozone were estimated. Associations of exposure with change in outcome and with attained outcome two years post‐surgery were examined. Results: Major‐roadway proximity was associated with reduced EWL and less improvement in lipid profile and ALP after surgery. NO2 was associated with less improvement in HbA1c and lower attained HDL levels and change in triglycerides over two years post‐surgery. PM2.5 was associated with reduced EWL and reduced beneficial change or attained levels for all outcomes except HbA1c. Conclusions: Near‐roadway, PM2.5 and NO2 exposures at levels common in developed countries were associated with reduced EWL and metabolic benefits of LAGB. This novel approach provides a model for investigating metabolic effects of other exposures. [ABSTRACT FROM AUTHOR]

The Texas Orocline is a prominent orogenic curvature that developed during the early Permian in the southern New England Orogen. Outliers preserving lower Permian sedimentary successions (Bondonga, Silver Spur, Pikedale, Terrica, Alum Rock and Ashford beds) approximately outline the oroclinal structure, but the tectonic processes responsible for the development of these basinal successions, and their relationships to the Texas Orocline, are unclear. Here we address this shortcoming by providing new U–Pb detrital and primary zircon ages from these successions, as well as detailed stratigraphic and structural data from the largest exposed succession (Bondonga beds). Field observations and U–Pb geochronological data suggest that the lower Permian successions in the Texas Orocline are remnants of a single, formerly larger basin that was deposited afterca302 Ma. Time constraints for formation of this basin are correlative with constraints from the lower Permian Nambucca Block, which was likely deposited in response to regional back-arc extension during and/or after the development of the Texas Orocline. The conclusion that the lower Permian sedimentary basins in the Texas Orocline belong to this back-arc extensional system supports the suggestion that oroclinal bending in the New England Orogen was primarily controlled by trench retreat and associated overriding-plate extension. [ABSTRACT FROM AUTHOR]

Reasons for performing study: Colic is a common reason for elimination from equine endurance competitions and has recently been identified as the leading cause of mortality in this group of horses. Hydration and electrolyte derangements are often severe, but are probably related to endurance exercise and not necessarily the episode of colic. Better understanding of the causes of colic and the expected outcome is needed to guide treatment decisions in endurance horses. Objectives: To describe the history, case details, clinical examination, laboratory, treatment and outcomes for horses presenting to equine referral centres for treatment of colic associated with endurance competition and to identify variables associated with prolonged hospitalisation. Methods: Thirty-six horses from 2 equine referral centres were included in the analysis. In addition to descriptive statistics, Cox proportional hazards models were used to evaluate factors associated with length of hospitalisation. Results: A diagnosis of open or ileus was made in the majority of horses (56%). Salmonellosis and enteritis ( Salmonella negative) were also recognised (16%). Exploratory abdominal surgery was performed in 5 of the horses. Only one of 36 horses did not survive to discharge. Previous eliminations from competition (negative association) and total i.v. fluids within the first 24 h (positive association) of admission were both associated with length of hospitalisation. Conclusions: Endurance horses with colic typically respond to medical treatment but in some cases hospitalisation may be prolonged. The role of Salmonella infections in endurance horses with colic requires further research. Potential relevance: Despite potentially severe clinical and laboratory derangements, equine practitioners should make owners aware that the prognosis for competing endurance horses with colic is good when treated appropriately. [ABSTRACT FROM AUTHOR]

Objective To describe the clinical and laboratory changes associated with the use of IV0.9% sodium chloride and a commercially available acetated fluid ( CAF) to treat endurance horses requiring emergency medical treatment. Design Randomized, controlled clinical trial from 2007 to 2010. Setting Emergency treatment centers of the Western States 100-mile (220 km) endurance ride. Animals Twelve horses requiring emergency medical treatment in the form of IVfluids completed the study. Interventions Horses were assigned to either the 0.9% sodium chloride group (6 horses) or CAF group (6 horses) and received a total of 20 L of fluid. Clinical, hematologic, and electrolyte data were collected prior to and during fluid therapy. Measurements and Main Results As compared to results prior to fluid therapy, horses treated with 0.9% sodium chloride had a decrease in heart rate ( P < 0.01), PCV ( P < 0.001), total plasma protein (TPP) ( P < 0.001), and the sodium-chloride difference ( P < 0.05). These horses also had an increase in plasma chloride ( P < 0.01) and sodium ( P < 0.01) concentrations. Horses treated with CAF showed a decrease in PCV ( P < 0.01) and TPP ( P < 0.001). Conclusions These findings should aid in the design a larger clinical trial to provide further clarification on the effects of type of fluid therapy on clinical and biochemical parameters in endurance horses. The use of 0.9% sodium chloride may not be ideal for the emergency management of endurance horses as it was associated with an increase in plasma chloride concentration. [ABSTRACT FROM AUTHOR]

Introduction Changes in arterial pressure due to respiratory phases have been used to predict fluid responsiveness in a number of species and pulse pressure variation ( PPV) and systolic pressure variation ( SPV) are commonly used. The relationship between PPV and SPV has not been described in horses. Objectives To describe and compare PPV and SPV values of horses under general anesthesia. Methods Twenty-six horses undergoing general anesthesia and receiving mechanical ventilation were enrolled in the study. Recordings of maximal and minimal values of pulse pressure and systolic pressure were calculated every 15 minutes throughout surgery. Results Initial PPV was 15.6% (7.9, 33.8) and decreased over the first 30 minutes to 10.7 ± 7.2% ( P = 0.03). Initial SPV was 10.3 ± 2.6% and decreased over the first 30 minutes to 7.3 ± 3.3% ( P = 0.004). PPV and SPV had a correlation coefficient of 0.52 ( P < 0.0001) and a 95% limits of agreement from −7.1% to 14.4%. Conclusion PPV and SPV measurements in horses do not have strong agreement. [ABSTRACT FROM AUTHOR]

Objective– To describe the clinical and clinicopathologic abnormalities in endurance horses eliminated from competition and requiring emergency medical treatment. Design– Retrospective study over a 2-year period (2005–2006). Ten horses that successfully completed the ride in 2006 were included for comparison. Setting– Temporary equine emergency field hospital. Animals– All horses ( n=30) that were removed from endurance competition and treated for a metabolic abnormality were studied. Interventions– Horses were treated with IV fluids and analgesics. Monitoring included lab work (PCV, total protein, and electrolytes) and serial physical examinations. Statistical analysis included descriptive statistics and parametric and nonparametric comparisons (ANOVA, Friedman's test, and Kruskal-Wallis) where appropriate. Measurements and Main Results– The clinical diagnoses identified included colic, esophageal obstruction, poor cardiovascular recovery, myopathy, and synchronous diaphragmatic flutter. As a group, these sick horses had lower plasma chloride and potassium and higher total plasma protein concentrations as compared with 10 healthy horses that successfully completed the ride ( P<0.05, <0.01, and <0.05 for chloride, potassium, and total protein, respectively). Horses with colic had a lower PCV as compared with horses with poor recovery and those with synchronous diaphragmatic flutter ( P<0.05). All horses, including colics, were treated medically and discharged to owners. Conclusions– Based on the results of this study, the prognosis for horses requiring emergency veterinary treatment after being removed from endurance competition (for metabolic reasons) appears to be good if horses are withdrawn from competition under the same criteria outlined in this study. Biochemical abnormalities tend to be mild and do not necessarily aid in delineating sick horses from successfully completing horses. None of the horses with gastrointestinal disease required abdominal surgery. [ABSTRACT FROM AUTHOR]

The sources and fluxes of sediment to the Great Barrier Reef lagoon from north-eastern Australian rivers have been the subject of much concern and study, with the large catchments of the Burdekin and Fitzroy Rivers thought to be the key sources at present. Here, the utility of newly developed magnetic ‘fingerprinting’ methods for identifying sediment provenance, both onshore and offshore, and in association with individual large flood events, is investigated. Within the Burdekin catchment, sediments are mobilized from different subcatchments by runoff generated by intense, localized rainfall events. Magnetic measurements were made on untreated and acid-treated samples of river channel sediments within the Burdekin River subcatchments and from the estuarine and inner shelf depocentres of Burdekin River sediments. The acid treatment removes all discrete magnetic particles and coatings, and leaves magnetic inclusions (protected within host silicate grains) as the basis of the measured magnetic signature of a sample. The magnetic properties of the acid-treated samples display statistically distinct sediment provenance groupings. Sand samples from the Upper Burdekin River appear magnetically distinct from samples from tributaries of the Burdekin (e.g. Hann Creek, Fanning River) and also from nearby coastal rivers, including the Haughton. Suspended sand samples from a Burdekin flood event in 2000 appear to have a different source compared with those from floods in 1998 and 1999. Comparisons of the terrestrial, acid-treated sand fractions with the same, acid-treated, sand-size fractions from transects taken offshore suggest that the surface sediments in Upstart Bay and Bowling Green Bay have different sources. Some of these sources are as yet unidentified but may represent the unsampled, lower-discharge south-western Burdekin subcatchments, and/or along-shore drift of sand from the south, perhaps even from the Fitzroy River, over millennial timescales of cyclone pumping. The magnetic inclusion method precludes any obfuscation or confounding of sediment source, which might arise from hydraulic sorting and/or post-depositional magnetic diagenesis or authigenesis. [ABSTRACT FROM AUTHOR]

AIMS: This paper draws together the personal thoughts and critical reflections of key people involved in the establishment of a 'virtual' practice development unit of clinical nurse specialists in the south of England. BACKGROUND: This practice development unit is 'virtual' in that it is not constrained by physical or specialty boundaries. It became the first group of Trust-wide clinical nurse specialists to be accredited in the UK as a practice development unit in 2004. DESIGN AND METHODS: The local university was asked to facilitate the accreditation process via 11 two-hour audio-recorded learning sessions. Critical reflections from practice development unit members, leaders and university staff were written 12 months after successful accreditation, and the framework of their content analysed. FINDINGS AND DISCUSSION: Practice development was seen as a way for the clinical nurse specialists to realize their potential for improving patient care by transforming care practice in a collaborative, interprofessional and evolutionary manner. The practice development unit provided a means for these nurses to analyse their role and function within the Trust. Roberts' identity development model for nursing serves as a useful theoretical underpinning for the reflections contained in this paper. CONCLUSIONS: These narratives provide another example of nurses making the effort to shape and contribute to patient care through organizational redesign. This group of nurses began to realize that the structure of the practice development unit process provided them with the means to analyse their role and function within the organization and, as they reflected on this structure, their behaviour began to change. RELEVANCE TO CLINICAL PRACTICE: Evidence from these reflections supports the view that practice development unit participants have secured a positive and professional identity and are, therefore, better able to improve the patient experience. [ABSTRACT FROM AUTHOR]

Aim. The context of this study is a group of clinical nurse specialists from across a Trust seeking accreditation as a practice development unit. The university was asked to facilitate the accreditation process via 11 2-hour learning sessions (including a one-hour focus group). During initial discussions between the university and practice development unit, the overarching research question for this study was set as: 'what are the main roles and responsibilities of clinical nurse specialists?' Background. Although there is no known study of a practice development unit based beyond a ward or speciality, the central tenet of the practice development unit literature is that units must demonstrate their worth if they are to survive and harness senior management support in doing so. Design and methods. Data gleaned from the transcribed audio tape-recordings of the learning sessions were studied at least three times to ensure transcription accuracy and produce detailed charts. Ethical approval was granted by the appropriate Local Research Ethics Committee and written informed consent obtained from clinical nurse specialists. The study lasted 30 months and ended in October 2004. Results. The four crucial statements that give meaning to specialist practice are: quality care giver; expert; information giver and initiator of change. Further analysis reveals the area of corporate and political practice as being missing from this and other lists of clinical nurse specialist attributes found in the literature. Clinical nurse specialists characterize their relationship with the Trust in terms of dichotomy - differing agendas and perceptions of value. Conclusions. The specialist role requires professional development in the areas of corporate and political acumen and professional business management. Relevance to clinical practice. While the findings of this study relate to one Trust and a group of 16 clinical nurse specialists, with careful application they may be transferable to other settings and groups of senior nurses. [ABSTRACT FROM AUTHOR]

Objective: To report the use of a hemoglobin-based oxygen carrier (HBOC) solution in the treatment of parasite-induced anemia in a Barbados sheep and to review the literature related to this disease. Case summary: A 3-month old Barbados sheep was found recumbent, anorexic, and pale. History, laboratory work, and physical examination findings were consistent with inadequate tissue oxygenation because of severe anemia from gastrointestinal parasites. The sheep was treated with 10 mL/kg of an HBOC solution and showed immediate improvement in clinical and laboratory data. The sheep was discharged and had a complete recovery. New information provided: The use of HBOC solutions in sheep has been previously confined to acute hemorrhage in a research setting. This report describes the effects of HBOC administration in an anemic animal displaying signs of inadequate oxygen delivery. [ABSTRACT FROM AUTHOR]

Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis of zircons confirm o Late Devonian to Early Carboniferous age (ca 360-350 Ma) for silicic volcanic rocks of the Compwyn Volcanics and Yarrol terrane of the northern New England Fold Belt (Queensland). These rocks ore coeval with silicic volcanism recorded elsewhere in the fold belt of this time (Connors Arch, Drummond Basin). The new U-Pb zircon ages, in combination with those from previous studies, show that silicic magmatism was both widespread across the northern New England Fold Belt (>250 000 km² and &les;500 km inboard of plate margin) and protracted, occurring over o period of -15 million years. Zircon inheritance is commonplace in the Late Devonian - Early Carboniferous volcanics, reflecting anatectic melting and considerable reworking of continental crust, Inherited zircon components range from ca 370 to co 2050 Ma, with Middle Devonian (385-370 Ma) zircons being common to almost ail dated units. Precambrian zircon components record either Precambrian crystalline crust or sedimentary accumulations that were present above or within the zone of magma formation. This contrasts with a lock of significant zircon inheritance in younger Permo-Carboniferous igneous rocks intruded through, and emplaced on top of, the Devonian-Carboniferous successions. The inheritance data and location of these volcanic rocks of the eastern margins of the northern New England fold Belt, coupled with Sr-Nd, Pb isotopic data and depleted mantle model ages for Late Palaeozoic and Mesozoic magmatism, imply that Precambrian mafic and felsic crustal materials (potentially as old as 2050 Ma), or of fhe very least Lower Palaeozoie rocks derived from the reworking of Precambrian racks, comprise basemen to the eastern parts of the foid belf. This crustal basement architecture may be a relief from the Late Proterozoic breakup of the Rodinian supercontinent. [ABSTRACT FROM AUTHOR]

To describe and compare admission colloid osmotic pressure (COP) measurement using both direct and indirect methods in neonatal foals under intensive care, and to evaluate for associations between COP and clinical/clinicopathologic parameters. Prospective study. Intensive care unit at a veterinary medical teaching hospital. Twenty-six critically ill neonatal foals were studied. A control group consisted of 9 clinically healthy neonatal foals. Clinicopathologic data were collected at the time of admission. COP was measured directly using a colloid osmometer. Indirect COP was calculated using equations by both Landis–Pappenheimer (L–P) and Thomas and Brown. Measured admission COP values were 17.1±4.3 and 17.7±2.4 mmHg in critically ill and control foals, respectively, and these values were not significantly different. Critically ill foals with blood lactate concentrations >3 mmol/L had lower COP values than those with lactate ≤3 mmol/L. There was close agreement between indirect COP values calculated using the L–P equation and direct COP values measured in control foals (mean error=0.0±1.3 mmHg; R2=0.87). However, indirect values were not as predictive of direct COP in critically ill foals (mean error=0.8±3.8 mmHg; R2=0.64). As COP values increased, the indirect method tended to overestimate COP, whereas at lower values it slightly underestimated COP. While the L–P equation was a close approximation of direct COP in healthy foals, direct measurements of oncotic pressure cannot be replaced for monitoring of critically ill foals. Critically ill foals with higher lactate concentrations had lower COP values, suggesting a possible relationship between COP and lactate. [ABSTRACT FROM AUTHOR]

Examines the types of physical non-linearities that exist in aircraft flight control systems. Analysis of non-linear stability; Amplitude limits; Rate limits; Jump resonance; Non-linear gearing/shaping.

Upper Devonian to Lower Carboniferous strata of the Campwyn Volcanics of east central Queensland preserve a substantial sequence of first-cycle volcaniclastic sedimentary and coeval volcanic rocks that record prolonged volcanic activity along the northern New England Fold Belt. The style and scale of volcanism varied with time, producing an Upper Devonian sequence of mafic volcano-sedimentary rocks overlain by a rhyolitic ignimbrite-dominated sequence that passes upward into a Lower Carboniferous limestone-bearing sedimentary sequence. We define two facies associations for the Campwyn Volcanics. A lower facies association is dominated by mafic volcanic-derived sedimentary breccias with subordinate primary mafic volcanic rocks comprising predominantly hyaloclastite and peperite. Sedimentary breccias record episodic and high energy, subaqueous depositional events with clastic material sourced from a mafic lava-dominated terrain. Some breccias contain a high proportion of attenuated dense, glassy mafic juvenile clasts, suggesting a syn-eruptive origin. The lower facies association coarsens upwards from a lithic sand-dominated sequence through a thick interval of pebble- to boulder-grade polymict volcaniclastic breccias, culminating in facies that demonstrate subaerial exposure. The silicic upper facies association marks a significant change in eruptive style, magma composition and the nature of eruptive sources, as well as the widespread development of subaerial depositional conditions. Crystal-rich, high-grade, low- to high-silica rhyolite ignimbrites dominate the base of this facies association. Biostratigraphic age controls indicate that the ignimbrite-bearing sequences are Famennian to lower-mid Tournaisian in age. The ignimbrites represent extra-caldera facies with individual units up to 40 m thick and mostly lacking coarse lithic breccias. Thick deposits of pyroclastic material interbedded with fine-grained siliceous sandstone and mudstone (locally... [ABSTRACT FROM AUTHOR]

Abstract. Strophingia ericae (Curtis) (Homoptera: Psylloidea) takes one or two years to complete its life cycle. In both cases eggs hatch over a prolonged period from midsummer, possibly extending into the following spring at high altitude, and instars overlap in time. Instar III is the predominant overwintering stage in the lowland, annual cycle, whereas in the upland, biennial cycle most first-year nymphs overwinter in instars I and II and most second-year nymphs in instar V. When moved to the laboratory, instars IV and V from a predominantly annual population showed accelerated development in response to elevated temperatures and to long days in both mid-winter and early spring. In the biennial life cycle, short autumn days retard instar V development but the response to photoperiod disappears by the end of winter. Exposure to LD 18 : 6 h retarded development of early instars in the annual population, resulting in an accumulation in instar III. The proportion of overwintering instars I and II rises with increase in altitude and moult to instar III becomes progressively delayed. Nymphs that reach instar III under long daylengths in the year following hatching are channelled towards the biennial cycle. Exposure of a predominantly biennial population to 15 °C and LD 18 : 6 h after midsummer, thus avoiding autumn conditions, promoted the rapid development of overwintered nymphs, switching the cycle from biennial to annual. [ABSTRACT FROM AUTHOR]

The Upper Devonian to Lower Carboniferous volcanosedimentary rocks of the Yarrol terrane of the northern New England Fold Belt have previously been ascribed to a forearc basin setting. New data presented here, however, suggest that the Yarrol terrane developed as a backarc basin during the Middle to early Late Devonian. Based on field studies, we recognise four regionally applicable stratigraphic units: (i) a basal, ?Middle to Upper Devonian submarine mafic volcanic suite (Monal volcanic facies association); (ii) the lower Frasnian Lochenbar beds that locally unconformably overlie the Monal volcanic facies association; (iii) the Three Moon Conglomerate (Upper Devonian - Lower Carboniferous); and (iv) the Lower Carboniferous Rockhampton Group characterised by the presence of oolitic limestone. Stratigraphic and compositional differences suggest the Monal volcanic facies association post-dates Middle Devonian silicic-dominated magmatism that was coeval with gold-copper mineralisation at Mt Morgan. The Lochenbar beds, Three Moon Conglomerate and Rockhampton Group represent a near-continuous sedimentary record of volcanism that changed in composition and style from mafic effusive (Late Devonian) to silicic explosive volcanism (Early Carboniferous). Palaeocurrent data from the Three Moon Conglomerate and Rockhampton Group indicate dispersal of sediment to the west and northwest, and are inconsistent with derivation from a volcanic-arc source situated to the west (Connors-Auburn Arch). Geochemical data show that the Monal volcanic facies association ranges from tholeiitic subalkaline basalts to calc-alkaline basaltic andesite. Trace and rare-earth element abundances are distinctly MORB-like (e.g. light rare earth element depletion), with only moderate enrichment of the large-ion lithophile elements in some units, and negative Nb anomalies, suggesting a subduction-related signature. Basalts of the Monal volcanic facies association are best described as transition... [ABSTRACT FROM AUTHOR]

The Westphalian (Upper Carboniferous) Coal Measures of the Durham coalfield in NE England were deposited in lower and upper delta plain environments. Distributory channels crossed the plain and were separated by shallow, interdistributary lakes and bays. Detailed observation of three-dimensional (3-D) opencast (surface) mine expousures, in collaboration with subsurface borehole analysis, has revealed the existence of five varieties of channel deposits and two associated overbank facies within the Durham Coal Measures. Major distributory channels were the major avenues of sediment transport across the Coal Measures plain, were variably sinous, mostly 1-2km wide and deposited belts of sand mostly up to 5 km wide. Proximal, major crevasse splay channels formed by the breaching of major channel banks during flood events, were straight, sand-filled and up to 400 m wide. Minor distributory channels formed by the sustained operation of such crevasses, varied from straight to highly sinous, and deposited 'shoestring' sand/mud belts up to a few hundred metres wide. Minor crevasse channels, generally straight and up to 50 m wide, were formed down-palaeocurrent extensions of minor distributaries which supplied interdistributary minor delta subsystems, were generally straight and up to 200 m wide. Of the two types of channel overbank (leave) deposits recognized, one comprising thinly interbedded fine-grained sandstone/claystone, is mostly, though not exclusively, associated with major distributary channels. The other, consisting of 'massive' siltstones with regularly spaced, thin claystone bands, is uniquely developed at the margins of minor distributary channels. The lower part of the Westphalian A succession in the northern Pennines records a change in the depositional environment upwards from a lower to upper delta plain. Through this transition, major channel deposits show evidence of having evolved from being of dominantly low sinuosity to being more variable in... [ABSTRACT FROM AUTHOR]

The early metabolism of cell-derived cholesterol was followed during the interaction of normolipaemic native plasma with cultured cell monolayers labelled to high specific activity with 3H-cholesterol. Kinetic analysis indicated that initial processing involved several prebeta-migrating high-density lipoprotein (HDL) species. A small prebeta species, the initial acceptor, was first converted to a lipoprotein whose composition predicts a discoidal structure. The free cholesterol content of this war then esterified by lecithin: cholesterol acyltransferase, and its cholesterol converted to the alpha mobility of spheroidal mature HDL the binding of apolipoprotein A-II. These studies follow the genesis of HDL in plasma from peripheral cell membrane cholesterol. [ABSTRACT FROM PUBLISHER]

A 3.5-year-old miniature horse gelding was evaluated for signs of colic and decreased faecal production. Initial clinical pathology showed severe hypoproteinaemia with an albumin concentration <10 g/l. Abdominal ultrasound identified multiple loops of small intestine with significantly increased wall thickness. Diagnosis of equine proliferative enteropathy was based on clinical and laboratory findings, as well as a positive faecal polymerase chain reaction and positive antibody titre (>1:240) to Lawsonia intracellularis. Treatment with intravenous oxytetracylcine and additional supportive care gradually resolved the clinical and laboratory abnormalities. [ABSTRACT FROM AUTHOR]

The characteristics, history, clinical signs, treatment and outcome of nine horses with abscesses caused by Actinomyces species were reviewed. DNA sequencing was used to determine the species of one of the isolates. The horses were one to 11 years of age, and the abscesses were most commonly located in the submandibular and retropharyngeal regions. The bacterium was usually cultured as the sole isolate and the horses were most often affected in the autumn. Most of the abscesses were treated with antimicrobials and drainage, but some of them recurred. The horses with submandibular abscesses had residual scar tissue that in some cases did not resolve. [ABSTRACT FROM AUTHOR]

The primary classes of drugs used for pain control in horses include the non-steroidal anti-inflammatory drugs (NSAIDS), the alpha-2 agonists, and the opiates, but each of these drug classes has significant adverse effects. Ketamine hydrochloride is a non-competitive antagonist at N-methyl D-aspartate (NMDA) receptors in the spinal cord and has been used in both dogs and humans to provide analgesia. The purpose of this study was to identify a safe administration rate for a continuous infusion of ketamine to awake horses and describe the clinical effects of this infusion. Six horses were administered a continuous infusion of ketamine hydrochloride at a low dose (0.4 mg/kg/hr) and high dose (0.8 mg/kg/hr). Each infusion took place over 6 hours and the horses were monitored during infusion as well as for the 6 hours post-infusion. The following parameters were evaluated: heart rate, blood pressure, respiratory rate, activity level, and analgesic thresholds. Both the low dose and high dose rates were tolerated well by all horses with no signs of excitation or discomfort. Post-infusion heart rate and mean arterial blood pressure were significantly decreased as compared to pre-infusion values (p=0.02 and p=0.02, respectively) A significant increase in analgesic threshold was not identified. Subanesthetic infusions of ketamine to awake horses appear to be well tolerated and cause only mild changes in clinical parameters. Further research is needed to evaluate the analgesic potential of these infusions. [ABSTRACT FROM AUTHOR]