The developmental and acute phases of insulin-induced laminitis involve minimal metalloproteinase activity

Metalloproteinases have been implicated in the pathogenesis of equine laminitis and other inflammatory conditions, through their role in the degradation and remodelling of the extracellular matrix environment. Matrix metalloproteinases (MMPs) and their inhibitors are present in normal equine lamellae, with increased secretion and activation of some metalloproteinases reported in horses with laminitis associated with systemic inflammation. It is unknown whether these enzymes are involved in insulin-induced laminitis, which occurs without overt systemic inflammation. In this study, gene expression of MMP-2, MMP-9, MT1-MMP, ADAMTS-4 and TIMP-3 was determined in the lamellar tissue of normal control horses (n = 4) and horses that developed laminitis after 48 h of induced hyperinsulinaemia (n = 4), using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Protein concentrations of MMP-2 and MMP-9 were also examined using gelatin zymography in horses subject to prolonged hyperinsulinaemia for 6 h (n = 4), 12 h (n = 4), 24 h (n = 4) and 48 h (n = 4), and in normal control horses (n = 4). The only change in gene expression observed was an upregulation of MMP-9 (p < 0.05) in horses that developed insulin-induced laminitis (48 h). Zymographical analysis showed an increase (p < 0.05) in pro MMP-9 during the acute phase of laminitis (48 h), whereas pro MMP-2 was present in similar concentration in the tissue of all horses. Thus, MMP-2, MT1-MMP, TIMP-3 and ADAMTS-4 do not appear to play a significant role in the pathogenesis of insulin-induced laminitis. The increased expression of MMP-9 may be associated with the infiltration of inflammatory leukocytes, or may be a direct result of hyperinsulinaemia. The exact role of MMP-9 in basement membrane degradation in laminitis is uncertain as it appears to be present largely in the inactive form.

Modeling train delays in urban networks

The reliability of urban passenger trains is a critical performance measure for passenger satisfaction and ultimately market share. A delay to one train in a peak period can have a severe effect on the schedule adherence of other trains. This paper presents an analytically based model to quantify the expected positive delay for individual passenger trains and track links in an urban rail network. The model specifically addresses direct delay to trains, knock-on delays to other trains, and delays at scheduled connections. A solution to the resultant system of equations is found using an iterative refinement algorithm. Model validation, which is carried out using a real-life suburban train network consisting of 157 trains, shows the model estimates to be on average within 8% of those obtained from a large scale simulation. Also discussed, is the application of the model to assess the consequences of increased scheduled slack time as well as investment strategies designed to reduce delay.

The use of amenities in high density neighbourhoods by older urban Australians residents

Like other major cities, Brisbane (Australia) has adopted policies to increase residential densities to meet the liveability goal of decreasing car dependence. This objective hinges on urban neighbourhoods being amenity-rich spaces, reducing the need for residents to leave their neighbourhood for everyday living. While older people are attracted to urban settings, there has been little empirical evidence linking liveability satisfaction with older people's use of urban neighbourhoods. Using a case study approach employing qualitative (diaries, in-depth interviews) and quantitative (Global Positioning Systems and Geographical Information Systems mapping) methods,this paper explores the effect of the neighbourhood environment and its influence on liveability for older urban people. Reliance on motor vehicles and issues with availability and access to local amenities inhibit local participation for older people. Highlighting these issues furthers our understanding of the landscape planning and design factors that make urban neighbourhoods more liveable for older residents.

Traffic-related fine and ultrafine particle exposures of professional drivers and illness : An opportunity to better link exposure science and epidemiology to address an occupational hazard?

Exposures to traffic-related air pollution (TRAP) can be particularly high in transport microenvironments (i.e. in and around vehicles) despite the short durations typically spent there. There is a mounting body of evidence that suggests that this is especially true for fine (b2.5 μm) and ultrafine (b100 nm, UF) particles. Professional drivers, who spend extended periods of time in transport microenvironments due to their job, may incur exposures markedly higher than already elevated non-occupational exposures. Numerous epidemiological studies have shown a raised incidence of adverse health outcomes among professional drivers, and exposure to TRAP has been suggested as one of the possible causal factors. Despite this, data describing the range and determinants of occupational exposures to fine and UF particles are largely conspicuous in their absence. Such information could strengthen attempts to define the aetiology of professional drivers' illnesses as it relates to traffic combustion-derived particles. In this article, we suggest that the drivers' occupational fine and UF particle exposures are an exemplar case where opportunities exist to better link exposure science and epidemiology in addressing questions of causality. The nature of the hazard is first introduced, followed by an overview of the health effects attributable to exposures typical of transport microenvironments. Basic determinants of exposure and reduction strategies are also described, and finally the state of knowledge is briefly summarised along with an outline of the main unanswered questions in the topic area.

Risk factors to predict the incidence of surgical adverse events following open or laparoscopic surgery for apparent early stage endometrial cancer: results from a randomised controlled trial

Aims: To identify risk factors for major Adverse Events (AEs) and to develop a nomogram to predict the probability of such AEs in individual patients who have surgery for apparent early stage endometrial cancer. Methods: We used data from 753 patients who were randomized to either total laparoscopic hysterectomy or total abdominal hysterectomy in the LACE trial. Serious adverse events that prolonged hospital stay or postoperative adverse events (using common terminology criteria 3+, CTCAE V3) were considered major AEs. We analyzed pre-surgical characteristics that were associated with the risk of developing major AEs by multivariate logistic regression. We identified a parsimonious model by backward stepwise logistic regression. The six most significant or clinically important variables were included in the nomogram to predict the risk of major AEs within 6 weeks of surgery and the nomogram was internally validated. Results: Overall, 132 (17.5%) patients had at least one major AE. An open surgical approach (laparotomy), higher Charlson’s medical co-morbidities score, moderately differentiated tumours on curettings, higher baseline ECOG score, higher body mass index and low haemoglobin levels were associated with AE and were used in the nomogram. The bootstrap corrected concordance index of the nomogram was 0.63 and it showed good calibration. Conclusions: Six pre-surgical factors independently predicted the risk of major AEs. This research might form the basis to develop risk reduction strategies to minimize the risk of AEs among patients undergoing surgery for apparent early stage endometrial cancer.

Effect of engine backpressure on the performance and emissions of a CI engine

This study investigated the effect of engine backpressure on the performance and emissions of a CI engine under different speed and load conditions. A 4-stroke single cylinder naturally aspirated direct injection (DI) diesel engine was used for the investigation with the backpressure of 0, 40, 60 and 80 mm of Hg at engine speed of 600, 950 and 1200 rpm. Two parameters were measured during the engine operation: one is engine performance (brake thermal efficiency and brake specific fuel consumption), and the other is the exhaust emissions (NOx, CO and odor). NOx and CO emission were measured by flue gas analyzer (IMR 1400). The engine backpressure produced by the flow regulating valve in the exhaust line was measured by Hg (mercury) manometer. The result showed that, the brake thermal efficiency and brake specific fuel consumption (bsfc) are almost unchanged with increasing backpressure up to 40 mm of Hg pressure for all engine speed and load conditions. The NOx emission became constant or a little decreased with increasing backpressure. The formation of CO was slightly higher with increase of load and back pressure at low engine speed condition. However, under high speed conditions, CO reduced significantly with increasing backpressure for all load conditions. The odor level was similar or a little higher with increasing backpressure for all engine speed and load conditions. Hence, backpressure up to a certain level is not detrimental for a CI engine.

Knee extensor strength differences in obese and healthy-weight 10-13 year olds

The purpose of this study was to investigate if obese children have reduced knee extensor (KE) strength and to explore the relationship between adiposity and KE strength. An observational case-control study was conducted in three Australian states, recruiting obese [n=107 (51 female, 56 male)] and healthy-weight [n=132 (56 female, 76 male)] 10–13 year old children. Body mass index, body composition (dual energy X-ray absorptiometry), isokinetic/isometric peak KE torques (dynamometry) and physical activity (accelerometry) were assessed. Results revealed that compared with their healthy-weight peers, obese children had higher absolute KE torques (P≤0.005), equivocal KE torques when allometrically normalized for fat-free mass (FFM) (P≥0.448) but lower relative KE torques when allometrically normalized for body mass (P≤0.008). Adjustments for maternal education, income and accelerometry had little impact on group differences, except for isometric KE torques relative to body mass which were no longer significantly lower in obese children (P≥0.013, not significant after controlling for multiple comparisons). Percent body fat was inversely related to KE torques relative to body mass (r= -0.22 to -0.35, P≤0.002), irrespective of maternal education, income or accelerometry. In conclusion, while obese children have higher absolute KE strength and FFM, they have less functional KE strength (relative to mass) available for weight-bearing activities than healthy-weight children. The finding that FFM-normalized KE torques did not differ suggests that the intrinsic contractile properties of the KE muscles are unaffected by obesity. Future research is needed to see if deficits in KE strength relative to mass translate into functional limitations in weight-bearing activities.

NOS1AP is associated with increased severity of PTSD and depression in untreated combat veterans

Background Post traumatic stress disorder (PTSD) and depressive disorder are over represented in combat veterans. Veterans with both disorders have an increased risk of suicide. The nitric oxide synthase 1 adaptor protein (NOS1AP) gene, which modulates stress-evoked N-methyl-D-aspartate (NMDA) activity, was investigated in combat veterans. Methods A comprehensive genetic analysis of NOS1AP and its association with PTSD was investigated in Vietnam combat veterans with PTSD (n=121) and a group of healthy control individuals (n=237). PTSD patients were assessed for symptom severity and level of depression using the Mississippi Scale for Combat-Related PTSD and the Beck Depression Inventory-II (BDI). Results The G allele of NOS1AP SNP rs386231 was significantly associated with PTSD (p = 0.002). Analysis of variance revealed significant differences in BDI-II and Mississippi scores between genotypes for rs386231 with the GG genotype associated with increased severity of depression (p = 0.002 F = 6.839) and higher Mississippi Scale for Combat-Related PTSD scores (p = 0.033). Haplotype analysis revealed that the C/G haplotype (rs451275/rs386231) was significantly associated with PTSD (p = 0.001). Limitations The sample sizes in our study were not sufficient to detect SNP associations with very small effects. In addition the study was limited by its cross sectional design. Conclusions This is the first study reporting that a variant of the NOS1AP gene is associated with PTSD. Our data also suggest that a genetic variant in NOS1AP may increase the susceptibility to severe depression in patients with PTSD and increased risk for suicide.

Development and validation of the consumer disillusionment toward marketing activity scale

This study examines disillusioned consumers. The theory proposes that this is a group learning to lower their expectations of firm integrity and who, to avoid being let down, ignore marketing activity directly from the firm. This kind of exchange orientation develops as a response to consistent failure in perceptions of firm integrity. The research includes six studies, including over 600 adult consumers, to outline the development and validation of a measure of consumer disillusionment toward marketing activity. Completing the process provides a valid and reliable four-item measure. In addition, the study includes the assessment of the nomological validity of the construct. The nomological validation includes using cue utilization theory to predict that disillusioned consumers favor advertising that provides evidence of verifiable integrity. The validation experiment uses print advertising containing high and low verifiable integrity stimuli. Results confirm the theory with disillusioned consumers focusing less on the firm as source of information. Further, these consumers respond more favorably than non-disillusioned consumers to third party endorsers who serve to verify the firm's attempts to show integrity.

The Development of Competency Standards for Specialist Critical Care Nurses

In defining the contemporary role of the specialist nurse it is necessary to challenge the concept of nursing as merely a combination of skills and knowledge. Nursing must be demonstrated and defined in the context of client care and include the broader notions of professional development and competence. This qualitative study sought to identify the competency standards for nurse specialists in critical care and to articulate the differences between entry-to-practice standards and the advanced practice of specialist nurses. Over 800 hours of specialist critical care nursing practice were observed and grouped into 'domains' or major themes of specialist practice using a constant comparison qualitative technique. These domains were further refined to describe attributes of the registered nurses which resulted in effective and/or superior performance (competency standards) and to provide examples of performance (performance criteria) which met the defined standard. Constant comparison of the emerging domains, competency standards and performance criteria to observations of specialist critical care practice, ensured the results provided a true reflection of the specialist nursing role. Data analysis resulted in 20 competency standards grouped into six domains: professional practice, reflective practice, enabling, clinical problem solving, teamwork, and leadership. Each of these domains is comprised of between two and seven competency standards. Each standard is further divided into component parts or 'elements' and the elements are illustrated with performance criteria. The competency standards are currently being used in several Australian critical care educational programmes and are the foundation for an emerging critical care credentialling process. They have been viewed with interest by a variety of non-critical care specialty groups and may form a common precursor from which further specialist nursing practice assessment will evolve.

Shear buckling characteristics of cold-formed steel channel beams

Cold-formed steel members are increasingly used as primary structural elements in the building industries around the world due to the availability of thin and high strength steels and advanced cold-forming technologies. Cold-formed lipped channel beams (LCB) are commonly used as flexural members such as floor joists and bearers. However, their shear capacities are determined based on conservative design rules. For the shear design of LCB web panels, their elastic shear buckling strength must be determined accurately including the potential post-buckling strength. Currently the elastic shear buckling coefficients of LCB web panels are determined by assuming conservatively that the web panels are simply supported at the junction between their flange and web elements. Hence finite element analyses were conducted to investigate the elastic shear buckling behavior of LCBs. An improved equation for the higher elastic shear buckling coefficient of LCBs was proposed based on finite element analysis results and included in the ultimate shear capacity equations of the North American cold-formed steel codes. Finite element analyses show that relatively short span LCBs without flange restraints are subjected to a new combined shear and flange distortion action due to the unbalanced shear flow. They also show that significant post-buckling strength is available for LCBs subjected to shear. New equations were also proposed in which post-buckling strength of LCBs was included.

Non-aqueous synthesis of hexagonal ZnO nanopyramids : gas sensing properties

Zinc oxide (ZnO) nanopyramids were synthesized by a one-pot route in a non-aqueous and surfactantfree environment. The synthesized metal oxide was characterized using SEM, XRD, and TEM to investigate the surface morphology and crystallographic phase of the nanostructures. It was observed that the ZnO nanopyramids were of uniform size and symmetrical, with a hexagonal base and height of ∼100 nm. Gas sensing characterization of the ZnO nanopyramids when deposited as thin-film onto conductometric transducers were performed towards NOx and C2H5OH vapor of different concentrations over a temperature range of 22–350 ◦C. It was observed that the sensors responded towards NO2 (10 ppm) and C2H5OH(250 ppm) analytes best at temperatures of 200 and 260 ◦C with a sensor response of 14.5 and 5.72, respectively. The sensors showed satisfactory sensitivity, repeatability as well as fast response and recovery towards both the oxidizing and the reducing analyte. The good performance was attributed to the low amount of organic impurities, large surface-to-volume ratio and high crystallinity of the solvothermally synthesized ZnO nanopyramids.