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Continued growth of tourism has led to concerns about direct and indirect impacts on the ecology of coral reefs and ultimate sustainability of these environments under such pressure. This research assessed impacts of reef walking by tourists on a relatively pristine reef flat community associated with an ‘ecoresort’ on the Great Barrier Reef, Australia. Heavily walked areas had lower abundances of live hard coral but greater amounts of dead coral and sediment. Abundances of macroalgae were not affected between sites. Coral-associated butterflyfish were less abundant and less diverse in more trampled sites. A manipulative experiment showed handling holothurians on reef walks had lasting negative impacts. This is the first study to show potential impacts of such handling on holothurians. Ecological impacts of reef walking are weighed against sociocultural benefits of a first hand experience in nature. [ABSTRACT FROM AUTHOR]

This paper uses a sensitivity analysis to quantify the dominant train properties (mass and spacing of wheels and bogies) that contribute to ground-borne vibration generation, with the aim of reducing the complexity of train–track numerical models. This research is significant because ground-borne vibration from railways is a growing problem, particularly in urban areas. Despite this fact, attempting to predict vibration levels is complex because there are many variables that contribute to the overall dynamic response. Therefore, a deterministic approach is commonly used, that ignores many of these variables. Thus, this paper identifies the variables that can be ignored, while highlighting those that are highly influential on vibration generation. For this purpose, a previously validated 2.5D finite elements-boundary elements approach is used to simulate dynamic train–track interaction. It is computed many times for a variety of modelling variables to investigate the effect of each on the ground-borne vibration levels in the far field. It is found that increases in unsprung mass of the train causes a large increase in vibration levels. Furthermore, changes in wheel/bogie spacing and semi-sprung mass are found to have a minimal effect on vibration generation. [ABSTRACT FROM PUBLISHER]

This paper presents a high precision train speed calculation technique based on ground vibration information. This versatile method can calculate speeds for trams, intercity locomotives and high speed trains on any track/embankment arrangement. Additionally, it has high accuracy for sensors located up to 100 m from the track, thus allowing semi-remote, non-invasive monitoring of train velocities. The calculation method combines three separate speed calculation techniques to provide estimates for arbitrary train speeds, even for sensors placed at large track offsets. The first estimation technique involves the use of cepstral analysis to isolate key harmonics for use with speed calculation. The second method is similar; however, the combination of a running rms and a previously developed “dominant frequency method” are used. The third method uses an analytical vibration frequency prediction model in combination with regression analysis to calculate train speed. All three methods are combined into one calculation procedure, resulting in high accuracy estimates. To show the robustness and ability of the new method to calculate a wide range of train speeds, it is used to predict tram, intercity and high speed rail train passage velocities generated from a previously validated vibration prediction numerical model. More importantly, it is used to predict train speeds during field trials performed on operational railway lines in Belgium and in UK. The new method is shown to offer high performance for several train types and track setups (including abutment and tunnel cases). [ABSTRACT FROM PUBLISHER]

Objectives To evaluate vena contracta and other echocardiographic measures of myxomatous mitral valve disease (MMVD) severity in a multivariable analysis of survival in dogs. Animals 70 dogs diagnosed with MMVD from stored echocardiographic images that met study inclusion criteria. Methods Left heart dimensions were measured as well as mitral regurgitant jet area/left atrial area (JAR), early mitral filling velocity (E vel ), extent of mitral valve prolapse in right and left views (Prol R , Prol L ), Prol indexed to aortic diameter (Prol R :Ao, Prol L :Ao), presence of a flail leaflet (Flail R , Flail L ), and mitral regurgitation vena contracta diameter (VC R , VC L ) indexed to aortic diameter (VC R :Ao, VC L :Ao). Follow-up from referring veterinarians was obtained by questionnaire or telephone to determine survival times. Inter- and intra-observer agreement was evaluated with Bland–Altman plots and weighted Kappa analysis. Survival was analyzed using Kaplan–Meier curves, logrank tests and Cox's proportional hazards. Results Logrank analysis showed VC L :Ao, VC R :Ao, Flail L, Prol R :Ao, Prol L :Ao, left ventricular internal dimension in diastole indexed to aortic diameter (LVIDD:Ao) >2.87, left atrium to aorta ratio (LA/Ao) >1.6, and E vel >1.4 m/s were predictors of cardiac mortality. In a multivariable analysis, the independent predictors of cardiac mortality were E vel >1.4 m/s [hazard ratio (HR) 5.0, 95% confidence interval (CI) 2.5–10.3], Flail L (HR 3.1, 95% CI 1.3–7.9), and Prol R :Ao (HR 2.8, 95% CI 1.3–6.3). Conclusions Echocardiographic measures of mitral regurgitation severity and mitral valve pathology provide valuable prognostic information independent of chamber enlargement in dogs with MMVD. [ABSTRACT FROM AUTHOR]

Objectives To compare red cell distribution width (RDW) between dogs with different causes of pulmonary hypertension (PH) and a control dog population to determine whether RDW was correlated with severity of PH as measured by echocardiography. A further aim was to determine the prognostic significance of increased RDW for dogs with PH. Animals Forty-four client-owned dogs with PH and 79 control dogs presented to a single tertiary referral institution. Methods Signalment, clinical pathological and echocardiographic data were obtained retrospectively from the medical records of dogs with PH, and RDW measured on a Cell-Dyn 3500 was compared between dogs with pre- and post-capillary PH and a control population. Referring veterinary surgeons were contacted for follow-up information and Kaplan–Meier analysis was conducted to investigate differences in survival time between affected dogs with different RDW values. Results The RDW was significantly greater in dogs with pre-capillary PH compared to control dogs. There was no difference in median survival times between dogs with PH divided according to RDW values. The RDW was positively correlated with mean corpuscular volume and haematocrit in dogs with PH, but did not correlate with echocardiographic variables. Conclusions An association was found between dogs with PH and increased RDW; however there was considerable overlap in values between control dogs and dogs with PH. The RDW was not associated with survival in this study. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: A mutation identified in the myosin binding protein C3 gene (MYBPC3 R820W) has been associated with hypertrophic cardiomyopathy (HCM) in Ragdoll cats. Ragdolls with HCM are reported to have a poor prognosis and homozygous cats seem particularly likely to develop severe HCM, although the outcome in Ragdolls tested for the MYBPC3 mutation has not been reported. We aimed to determine the influence of genotype on survival in Ragdoll cats using a questionnaire, and hypothesized that homozygous Ragdolls had shorter lifespans and were more likely to suffer cardiac death than heterozygous or wild-type (WT) cats. Animals: 251 client owned Ragdoll cats. Methods: A questionnaire for breeders/owners of MYBPC3 genotyped Ragdolls included items related to genotype, age, sex, current status (alive/dead), and date and circumstances of death. Death was categorized as cardiac or non-cardiac. Survival was analyzed using Kaplan–Meier curves and log rank tests. Results: Completed questionnaires were received for 236 cats (156 WT, 68 heterozygous, 12 homozygous). Median survival time for homozygous cats was 5.65 years (95%CI 0.4–10.9 years) compared to heterozygous (>16.7 years) or WT (>15.2 years). Homozygous cats were more likely to die from cardiac death (p = 0.004 vs. WT; p = 0.003 vs. heterozygous) and had significantly shorter time to cardiac death (vs. WT p < 0.001; vs. heterozygous p < 0.001). Conclusions: Ragdoll cats homozygous for the MYBPC3 R820W mutation have a shorter survival time than WT or heterozygous cats. This suggests a mode of inheritance that follows an incomplete dominance pattern. [Copyright &y& Elsevier]

Abstract: Objectives: To evaluate whether the addition of a protease inhibitor (PI) to feline plasma improves the temporal stability of N-terminal pro-B-type natriuretic peptide (NT-proBNP). Animals, materials and methods: Forty-four EDTA blood samples were collected from 42 cats with cardiac disease or hyperthyroidism. Samples were separated within 15 min of collection and the plasma stored at −80 °C. Samples were thawed and each separated into 2 aliquots, one of which was mixed with PI. Each was subdivided into 5 aliquots, which remained at room temperature (RT) for zero, 24, 48, 96 or 120 h before being returned to storage at −80 °C. NT-proBNP was measured using a commercially-available ELISA. Results: There was no difference in NT-proBNP measurements between plain and PI samples at time zero (P = 0.836) or 24 h (P = 0.293). At subsequent time-points NT-proBNP was higher in the PI than the plain samples (P < 0.05). An overall effect of time at RT was detected for plain (P < 0.001) and PI samples (P < 0.001). Conclusions: The addition of PI to feline plasma significantly reduces, but does not eliminate, degradation of NT-proBNP at RT. This degradation occurs over a time course comparable to postal transportation of samples for laboratory analysis and may alter the clinical interpretation of results. [Copyright &y& Elsevier]

Objectives: To determine whether serum N-terminal B-type natriuretic peptide (NT-proBNP) concentration in normal dogs, and dogs with heart disease, is affected by freezing, or by sample ageing when stored at room temperature. Animals, materials and methods: Thirty six dogs with heart disease and ten normal dogs. Serum NT-proBNP was measured within 60min of sample collection. Serum was also frozen at −20°C and NT-proBNP measurement was repeated at 1, 24, 48, 72 and 96h after thawing. Results: Median NT-proBNP increased significantly after freezing (p <0.005) and then progressively decreased at all time points after thawing (p <0.005). Conclusions: Serum NT-proBNP concentration increases with freezing, and then rapidly decreases over time when stored at room temperature. Concentrations were sufficiently increased after freezing and decreased after 24h at room temperature to affect interpretation. The authors recommend that serum for NT-proBNP assay should be frozen within 1h of sampling and submitted frozen in cold packs. [Copyright &y& Elsevier]

Abstract: Objective : To determine if serum cardiac troponin I (cTnI) concentrations can distinguish cardiac from non-cardiac causes of respiratory distress (RD) in cats. Animals, materials and methods : 53 cats. cTnI concentrations were measured in 30 cats with non-cardiac respiratory distress (RD-NC) and compared to 23 cats with RD due to congestive heart failure (RD+CHF). Results : The RD+CHF group had higher median cTnI concentration (0.94ng/ml interquartile range IQR 0.54–4.00, range <0.20 – 90.14) than the RD-NC group (<0.2ng/ml IQR <0.2–0.33, range <0.20–41.1, p <0.001). The area under the curve (AUC) was 0.842 (95% CI 0.728–0.955) for the receiver operator curve (ROC) analysis of the accuracy of cTnI concentrations to discriminate RD+CHF from RD-NC cats. A cut-off of ≥0.81ng/ml discriminated RD+CHF from RD-NC cats with a sensitivity and specificity of 65.2% and 90.0% respectively. However considerable overlap in cTnI concentrations between the 2 groups was identified. Conclusions : Serum cTnI concentrations were different in RD+CHF compared to RD-NC cats. However the overlap in cTnI concentrations between the 2 groups reduced the clinical efficacy of the assay which therefore should not be used as a stand-alone test but in combination with other diagnostics such as echocardiography and radiography. [Copyright &y& Elsevier]

Classification of pleural effusion (PE) is central to diagnosis. Traditional veterinary classification has distinguished between transudates, modified transudates and exudates. In human medicine PEs are divided into only two categories: transudates and exudates. The aim of this study was to evaluate, in 20 cats presented with PE, paired samples of serum and pleural fluid for the following parameters: Light''s criteria (pleural fluid lactate dehydrogenase concentration (LDHp), pleural fluid/serum LDH ratio, pleural fluid/serum total protein ratio (TPr)), pleural fluid total protein, pleural fluid cholesterol concentration, pleural fluid/serum cholesterol ratio (CHOLr), serum-effusion cholesterol gradient (serum cholesterol minus PE cholesterol concentration (CHOLg)), PE total nucleated cells count (TNCCp) and pleural fluid glucose (GLUp). LDHp and TPr were found most reliable when distinguishing between transudates and exudates, with sensitivity of 100% and 91% and specificity of 100%, respectively. When conflict between the clinical picture and laboratory results exists, calculation of CHOLr, CHOLg and TNCCp measurement may help in the classification of the effusion. Measurement of serum albumin (in the case of a transudate) may provide additional information regarding the pathogenesis of the effusion. [Copyright &y& Elsevier]

The article focuses on a study on the risk of prostate cancer in men due to the widespread use of prostate-specific antigen (PSA) testing in Northern Ireland. It discusses the results of the study which provide data to inform men who have a low baseline PSA of their risk of prostate cancer and prostate cancer-specific mortality if they do not undergo early investigation. It stresses the need for men to be aware of the harm cancer may cause them.

Abstract: Acquired tricuspid valve stenosis (TVS) is a rare complication of endocardial lead placement in humans that has not been described in the veterinary literature. We describe a 6.5-year-old Border terrier that was presented with right-sided congestive heart failure 5.5 years after placement of a transvenous pacemaker. Severe TVS was confirmed by cardiac ultrasonography and appeared to be secondary to excessive endocardial pacemaker lead within the right atrium. Repositioning of the lead proved impossible and subsequent postmortem examination demonstrated fusion of the tricuspid valve (TV) leaflets around the endocardial lead with associated narrowing of the tricuspid valve orifice. In addition, the loop of the endocardial lead was anchored by thick fibrous tissue to the right atrial wall. This case report suggests that if sufficient endocardial lead is left inside the heart, in dogs undergoing transvenous pacemaker therapy, the redundant lead can become adherent to the tricuspid valve apparatus and cause valvular stenosis. [Copyright &y& Elsevier]

The article reports on the various modeling approaches that can be applied to different kinds of multiphase separation vessels used in the chemical process industries. It provides a brief introduction to multiphase modeling with computational fluid dynamics (CFD) and visual dynamic modeling (VDM). The article also describes how CFD and VDM can be applied to the analysis of separator systems.

Abstract: This case illustrates an unusual presentation of atrial fibrillation in a 10-year-old male neutered Maine coon. At the time of diagnosis of the arrhythmia the size of the left atrium determined by echocardiography was within normal limits and no structural or functional heart or other systemic disease was identified. Traditionally it has been suggested that the atria must be of a sufficient size in order to sustain atrial fibrillation (multiple wavelet theory) and therefore only cats with significant cardiac disease can attain sufficiently large atria to sustain this arrhythmia. To the author''s knowledge this is the first detailed case report of sustained atrial fibrillation in a cat with a normal sized left atrium and no obvious structural heart disease seen on cardiac ultrasound. [Copyright &y& Elsevier]

The dynamic response of a railway bridge can be affected by the properties of its foundations, particularly if founded on soft soils. Thus, this work aims to establish a coupled dynamic model to investigate the vibration of train-track-bridge systems considering piled foundations embedded in soft soil. Firstly, to construct the simulation framework, the finite element and multi-body methods are used to model the dynamic behavior of a train-track-bridge interaction (TTBI) system and a pier-cap-pile-soil interaction system. The equilibrium of the two sub-systems is maintained through the bridge's bearing force and a multi-time-step integration strategy is introduced to improve computational efficiency. The proposed model is validated by comparing it to the results from commercial finite element software ABAQUS. Then results are computed using the proposed model and the conventional TTBI model without piles. It is concluded that when considering the piled foundations, the low-frequency vibration of the TTBI system is dominant. Moreover, the vibration energy in the track and bridge below 7 Hz is larger compared with the conventional TTBI model. The influence of train speed on the vibration characteristics of the pile and soil is analyzed. It is found that higher train speeds cause increased pile and soil accelerations at the frequencies associated with the train axle spacing. The novelty of the analysis is providing a new insight into the coupled vibration properties of TTBI systems considering the participation of piled foundations in soft soil. • A dynamic model is established to investigate the coupled vibration of train-bridge interaction considering piled foundation in soft soil. • The vibration transmission of train-bridge-pile-soil interaction is analyzed and quantified. • The power flow is used to depict the train-induced vibration level of structures subjected to the piles embedded in soft soil. [ABSTRACT FROM AUTHOR]

The article reviews several information resources on teaching business and economics, including "Business Case Studies - Applied GCSE Business," by Margaret Hancock and John Evans-Pritchard from Causeway Press, "Business and Management," by Paul Hoang from IBID Press, and the eBusiness Course Companion software from eHarris Learning.

A personal narrative is presented which explores the author's experience of preparing for the offering of the Manufacturing and Product Design (MPD) Diploma in Great Britain.

Objectives To investigate the effect of various genetic and environmental modifiers on left ventricular (LV) wall thickness in a cohort of cats genotyped for the myosin binding protein C3 mutation (MYBPC3). Animals Sixty-four Ragdoll cats. Methods All cats were screened for HCM with echocardiography and genotyping for the HCM-associated MYBPC3:R820W mutation. Cats were also genotyped for previously identified variant polymorphisms of the angiotensin-converting enzyme (ACE) and cardiac beta-adrenergic receptor (ADRB1) genes. Plasma N-terminal pro-B-type natriuretic peptide and cardiac troponin I were also measured. Associations were evaluated between genotype (MYBPC3 negative/positive, and ACE and ADRB1 negative/heterozygous/homozygous), patient factors (body weight, age and sex) and echocardiographic measurements of LV wall thickness. Results Male cats had greater maximum wall thickness (LV max ; 5.8 mm, IQR 5.1–6.4 mm) than females (4.7 mm, IQR 4.4–5.3 mm, p = 0.002). Body weight positively correlated with LV max ( ρ = 0.604, p < 0.001). The MYBPC3:R820W-positive cats had a greater LV max (5.44 mm, IQR 4.83–6.28 mm) than the negative cats (4.76 mm, IQR 4.36–5.32 mm, p = 0.001). Also, the ACE polymorphism genotype was associated with LV max : the homozygous cats (5.37 mm, IQR 5.14–6.4 mm) had greater LV max than the heterozygous cats (4.73 mm, IQR 4.41–5.55 mm, p = 0.014). Only the MYBPC3 genotype and body weight were independently associated with wall thickness in multivariable analysis. Conclusions This study provides evidence that the MYBPC3:R820W mutation is independently associated with LV wall thickness in Ragdoll cats. Body weight is also independently associated with maximum LV wall thickness, but is not currently accounted for in HCM screening. In addition, other genetic modifiers may be associated with variation in LV wall thickness in Ragdolls. [ABSTRACT FROM AUTHOR]