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The simulation of the complex flow in a wind turbine wake is a challenging problem. To date, much of the research has been inhibited by both the time and computational costs associated with turbulence modelling. Additionally, the majority of numerical investigations focus on turbine performance and therefore neglect the near wake of a Horizontal Axis Wind Turbine (HAWT) entirely. This investigation focuses on experimentally and numerically quantifying the near wake structure of a model HAWT. The Shear Stress Transport (SST) k − ω , Elliptical-Blending Reynolds Stress Model (EB-RSM) and the Reynolds Stress Transport (RST) turbulence models were used to model a turbine wake in the current study, with the results verified against experimental hot-wire data. Near wake velocity and turbulence characteristics were investigated to determine if low-order models can accurately predict the magnitude and distribution of velocity and turbulence values in the near wake of a model HAWT. The HAWT model was operated at two TSR values of 2.54 and 3.87. All models predicted velocity deficit values to within 2–4% and 4–7% of experimental results for TSR values of 2.54 and 3.87 respectively. Results showed that all models were able to accurately predict the mean velocity deficit generated in the near wake. All models were able to predict the fluctuating u and v velocity components in the near wake to the correct order of magnitude with the fluctuating velocity components having an inverse Laplace distribution in the wake. However, all models under-estimated the magnitude of these velocity values with predictions as low as −43% of experimental results.

A review of wind turbine aerodynamics research is presented. The review is limited to Horizontal Axis Wind Turbine (HAWT) investigations. The focus is on recent near wake experiments, wake predictions by commercial CFD codes and current FSI and structural modelling attempts. For the near wake, the review considers experiments carried out in controlled conditions whereby the incoming freestream is perpendicular to the rotor plane. Additional anomalies such as wind shear, gusts and yaw transition are not considered. The survey of 3D commercial codes is also focused on HAWT models in parallel flow conditions. Finally, the structural models reviewed are divided into two separate categories: 1) blade deflection and performance under aerodynamic loads, and 2) the vibrational response of blades under aerodynamic loading. The aim is to highlight common trends within near wake experiments and investigate both CFD and FE modelling strategies – to identify current limitations and future opportunities within the sector.

l-lysine (Lys) is an essential amino acid that is added to foods and dietary supplements. Lys may interact with mineral nutrients and affect their metabolism. This study examined the effect of dietary Lys supplementation on the bioavailability of copper (Cu) and iron (Fe). Weanling male Sprague-Dawley rats were fed one of five diets (20% casein) for 4 weeks containing normal Cu and Fe (control) or low Cu or Fe without (LCu, LFe) or with (LCu+Lys, LFe+Lys) addition of 1.5% Lys. Final body weights, body weight gains and food consumption of the rats did not differ (P≥0.05) among diet groups. Rats fed the low Cu or Fe diets showed changes in nutritional biomarkers compared to control rats, demonstrating reduced Cu and Fe status, respectively. Hematological parameters, serum ceruloplasmin activity and Cu and Fe concentrations in serum, liver, kidney and intestinal mucosa were unaffected (P≥0.05) by Lys supplementation. These results indicate that in the context of an adequate protein diet, Lys supplementation at a relatively high level does not affect Cu or Fe bioavailability in rats.

ObjectivesTo assess the health burden of breast hypertrophy and the comparative effectiveness of breast reduction surgery in improving health-related quality of life.DesignProspective cohort study.SettingA major public tertiary care hospital in Australia.ParticipantsWomen with symptomatic breast hypertrophy who underwent breast reduction surgery were followed for 12 months. A comparison control cohort comprised women with breast hypertrophy who did not undergo surgery.InterventionsBilateral breast reduction surgery for women in the surgical cohort.Main outcome measuresThe primary outcome measure was health-related quality of life measured preoperatively and at 3, 6 and 12 months postoperatively using the Short Form-36 (SF-36) questionnaire. Secondary outcome measures included post-surgical complications.Results209 patients in the surgical cohort completed questionnaires before and after surgery. 124 patients in the control hypertrophy cohort completed baseline and 12-month follow-up questionnaires. At baseline, both groups had significantly lower scores compared with population norms across all scales (pConclusionBreast reduction significantly improved quality of life in women with breast hypertrophy. This increase was most pronounced within 3 months of surgery and sustained at 12-month follow-up. This improvement in quality of life is comparable to other widely accepted surgical procedures. Furthermore, women benefit from surgery regardless of factors including body mass index and resection weight.

The creation of an arteriovenous fistula offers a unique example of vascular remodelling and adaption. Yet, the specific factors which elicit remodelling events which determine successful maturation or failure have not been unambiguously determined. Computational fluid dynamic (CFD) simulations are increasingly been employed to investigate the interaction between local hemodynamics and remodelling and can potentially be used to assist in clinical risk assessment of maturation or failure. However, these simulations are inextricably linked to their prescribed boundary conditions and are reliant on in vivo measurements of flow and pressure to ensure their validity. The study compares in vivo measurements of the pressure distribution across arteriovenous fistulae against a representative numerical model. The results of the study indicate relative agreement (error ≈ 8-10%) between the in vivo and CFD prediction of the mean pressure drop across the AVFs. The large pressure drop across the AVFs coincided with a palpable thrill (perivascular vibration) in vivo and fluctuations were observed in the numerical pressure drop signal due to flow instabilities arising at the anastomosis. This study provides a benchmark of the pressure distribution within an AVF and validates that CFD solutions are capable of replicating the abnormal physiological flow conditions induced by fistula creation.

A strong correlation between the localization of atherosclerotic lesions with abnormal wall shear stress (WSS) has long been recognized at the distal anastomosis of a peripheral bypass where disturbed flow occurs. Identification of a WSS variable that significantly contributes to disease formation at this site has been elusive to date, as endothelial cell (EC) response to the abnormal hemodynamics at this anastomotic junction has yet to be quantitatively characterized. In vitro experiments were performed exposing human aortic ECs to pulsatile flow variables appropriate to a distal bypass graft junction using a novel in vitro device. Computational fluid dynamics was employed to detail the hemodynamic variables of this flow chamber. These variables were then correlated to EC proliferation which was used as an indicator of intimal hyperplasia (IH) development. Under pulsatile flow, maximum absolute temporal WSS gradient was found to be the parameter that most significantly correlated to EC proliferation (p = 0.0001, r = 0.8947). This metric can be utilized as an indicator to detect arterial segments prone to the initiation and localization of IH, it may also be used to help optimize the surgical construction of coronary artery bypass, peripheral bypass and arteriovenous anastomotic junctions to improve patient outcomes.

Sodium (Na) and potassium (K) are essential nutrients. Like people in many Western societies, Canadians consume too much Na and not enough K, both of which contribute to hypertension. We analysed the Na and K content of 154 food composites, broadly representative of the foods most commonly consumed in Canada, from the Canadian Total Diet Study collection of 2007. Foods were prepared as if for home consumption before compositing. No salt was added during food preparation. Samples prepared by aqueous extraction were analysed by atomic emission (Na) or atomic absorption spectrometry (K). Processed foods and soups contained large amounts of Na per reference amount (serving) of the food, with 17 samples containing over 1/3 of the Adequate Intake (AI) for adults, or >500 mg Na/serving. Fluid milk, unprocessed meats and several fruits and vegetables contained large amounts of K per reference amount, with 11 samples containing over 10% of the AI for adults, or >470 mg K/serving. Na:K molar ratios were typically either high or low, with few values near unity. Thus, with few exceptions, foods high in Na were lower in K, and vice versa. Through judicious food selection it may be possible for consumers to decrease Na intake while increasing K, with associated health benefits. Such choices would be consistent with common nutrition advice to decrease consumption of processed foods, while increasing intakes of fresh fruits and vegetables.

The records of 30 patients who had suffered from vertebral osteomyelitis were reviewed. They conformed to a constant pattern, though varying in terms of: (i) the severity of the disease, due to host-organism interrelationship; and (ii) age distribution. Causative organisms could not always be identified, though all lesions settled with conservative measures of rest and antibiotics. A high proportion of the patients who were followed up for more than one year were back at work. The anatomical distribution of the lesions can be explained by our knowledge of the vascular supply to the vertebral bodies.

Introduction Non-maturation and post-maturation venous stenosis are the primary causes of failure within arteriovenous fistulae (AVFs). Although the exact mechanisms triggering failure remain unclear, abnormal hemodynamic profiles are thought to mediate vascular remodelling and can adversely impact on fistula patency. Aim The review aims to clarify the role of shear stress on outward remodelling during maturation and evaluate the evidence supporting theories related to the localisation and development of intimal hyperplasia within AVFs. Methods A systematic review of studies comparing remodelling data with hemodynamic data obtained from computational fluid dynamics of AVFs during and after maturation was conducted. Results Outward remodelling occurred to reduce or normalise the level of shear stress over time in fistulae with a large radius of curvature (curved) whereas shear stress was found to augment over time in fistulae with a small radius of curvature (straight) coinciding with minimal to no increases in lumen area. Although this review highlighted that there is a growing body of evidence suggesting low and oscillating shear stress may stimulate the initiation and development of intimal medial thickening within AVFs. Further lines of evidence are needed to support the disturbed flow theory and outward remodelling findings before surgical configurations and treatment strategies are optimised to conform to them. This review highlighted that variation between the time of analysis, classification of IH, resolution of simulations, data processing techniques and omission of various shear stress metrics prevented forming pooling of data amongst studies. Conclusion Standardised measurements and data processing techniques are needed to comprehensively evaluate the relationship between shear stress and intimal medial thickening. Advances in image acquisition and flow quantifications coupled with the increasing prevalence of longitudinal studies commencing from fistula creation offer viable techniques and strategies to robustly evaluate the relationship between shear stress and remodelling during maturation and thereafter.

High powered laser diodes are used in many applications that require stable optical output, such as materials processing, medical and military applications, and solid-state laser pumping [1,2]. Due to the low electrical to optical efficiencies of 25-35%, significant waste heat is generated which increases the junction temperature and alters the wavelength of the emitted beam. The industry standard for rejecting this waste heat is single-phase, copper microchannel cooler (MCC) using high-purity de-ionized water (DIW) coolant. However, the high-purity DIW coolant is pumped through the copper MCCs in presence of leakage current at high velocity, which causes erosion-corrosion damage to the micron sized heat transfer surface areas, and reduces the thermal performance of the cooler. Since the corrosion of copper is highly dependent on the pH and dissolved oxygen (DO) content of the DIW coolant, strict control on water conditioning system is employed. This strict control scheme leads to additional equipment, costs and reliability concerns. Extension of the cooler lifetime by protecting the MCCs against erosion-corrosion can be achieved by applying a uniform, pin-hole free and conformal coating to the internal features of the MCCs. However, many coating and plating techniques, such as nickel and gold plating, cannot meet these requirements. Thus, a vapor phase deposition technique that uniformly applies a nanometer thin, conformal, inert, hard, coating to the high-aspect ratio internal features of the MCC was developed to protect the copper MCC against erosioncorrosion in high powered laser diode applications. Corrosion rate measurements of baseline uncoated and coated copper samples exhibited a one to two order of magnitude reduction in corrosion rate when exposed to DIW with a pH of 6.0 – 9.0 and a DO concentration ranging from 0.5 ppm to 10.0 ppm. This study shows that the strict controls required to maintain the pH and DO can be severely relaxed by applying the coating resulting in reduced operational costs and increased reliability. Furthermore, evaluations of the coating thickness deposited throughout the microchannel region of the MCC demonstrate the uniform and conformal application of the coating in the high aspect ratio features. Lastly, thermal and hydraulic performance evaluations of coated MCCs revealed that the application does not impede the thermal or hydraulic performance of the MCC, thereby enabling lifetime extension without adding pumping po wer requirements.

Hypercholesterolemia diets are associated with oxidative stress that may contribute to hypercholesterolemia by adversely affecting enzymatically-generated oxysterols involved in cholesterol homeostasis. An experiment was conducted to examine whether the cholesterol-lowering effects of the antioxidants selenium and α-tocopherol were related to hepatic oxysterol concentrations. Four groups of male Syrian hamsters (n = 7-8) were fed high cholesterol and saturated fat (0.46% cholesterol, 14.3% fat) hypercholesterolemic semi-purified diets: 1) Control; 2) Control + α-tocopherol (67 IU all-racemic-α-tocopheryl-acetate/kg diet); 3) Control + selenium (3.4 mg selenate/kg diet); and 4) Control + α-tocopherol + selenium. Antioxidant supplementation was associated with lowered plasma cholesterol concentrations, decreased tissue lipid peroxidation and higher hepatic oxysterol concentrations. A second experiment examined the effect of graded selenium doses (0.15, 0.85, 1.7 and 3.4 mg selenate/kg diet) on mRNA expression of the oxysterol-generating enzyme, hepatic 27-hydroxylase (CYP27A1, EC 1.14.13.15), in hamsters (n = 8-9) fed the hypercholesterolemic diets. Supplementation of selenium at 3.4 mg selenate/kg diet was not associated with increased hepatic 27-hydroxylase mRNA. In conclusion, the cholesterol lowering effects of selenium and α-tocopherol were associated with increased hepatic enzymatically generated oxysterol concentrations, which appears to be mediated via improved antioxidant status rather than increased enzymatic production.

Microscale fluid dynamics has played a significant role in the development of many applications in the medical diagnostic sector and in recent years many devices have implemented advances in this field. Capillary driven assays are commonly used in diagnostic areas, such as, cardiac risk, fertility, drug abuse and infectious diseases1. Typically a platform is used where bodily fluids or samples are taken, filtered and by means of small microchannels, transported and mixed with a variety of antibodies2. In order to perform correctly, these antibodies need to bind to the proteins in the fluid. It is therefore essential that the exposure of the proteins to the antibodies is maximized. To achieve this, capillary dimensions can be altered to obtain the required flow rates and exposure times3. This paper focuses on controlling these parameters. In this paper, a study was conducted in which the flows in four straight rectangular microchannels of varying cross sectional areas were assessed. The four microchannels were fabricated from an epoxy material. The microchannel widths varied from 100μm to 1000μm with each channel having a dept of 200μm. The four microchannels had aspect ratios of 0.5, 1, 2 and 10. The microchannels were sealed using a heat sealing hydrophilic tape. Fluid velocity rates were measured experimentally using an X-Stream XS-4 high speed camera at 500 frames per second. Preliminary contact angle results between water and the epoxy material gave a contact angle of 81.5 degrees +/− 6 degrees. Computational models of the four microchannels were performed using a Volume Of Fluid (VOF) model in Fluent 6.2.16, a commercially available CFD code. The computational models had four boundary types: pressure inlet, pressure outlet, epoxy wall and hydrophilic tape wall. The inlet boundary has an initial pressure applied to it, capillary pressure between the water and air interface in the microchannel. It was found that as the dimensions of the microchannels increased, the governing equations were less accurate in predicting the experimental fluid velocity in the microchannels.

Objectives Abacavir (ABC) selects for four mutations (K65R, L74V, Y115F and M184V) in HIV-1 reverse transcriptase (RT), both in vitro and during monotherapy in vivo. The aim of this analysis was to compare the selection of these and other nucleoside reverse transcriptase inhibitor (NRTI)-associated mutations by ABC-containing therapies in the presence and absence of concurrent lamivudine (3TC) and/or zidovudine (ZDV) and to assess the effect of these mutations on phenotypic susceptibility to the NRTIs. Design This study was a retrospective analysis of the patterns of NRTI-associated mutations selected following virological failure in six multicentre trials conducted during the development of ABC. Methods Virological failure was defined as confirmed vRNA above 400 HIV-1 RNA copies/mL. RT genotype and phenotype were determined using standard methods. Results K65R was selected infrequently by ABC-containing regimens in the absence of ZDV (13 of 127 patients), while L74V/I was selected more frequently (51 of 127 patients). Selection of both K65R and L74V/I was significantly reduced by co-administration of ZDV with ABC (one of 86 and two of 86 patients, respectively). Y115F was uncommon in the absence (seven of 127 patients) or presence (four of 86 patients) of ZDV. M184V was the most frequently selected mutation by ABC alone (24 of 70 patients) and by ABC plus 3TC (48 of 70 patients). Thymidine analogue mutations were associated with ZDV use. The K65R mutation conferred the broadest phenotypic cross-resistance of the mutations studied. Conclusions The resistance pathway selected upon virological failure of ABC-containing regimens is significantly altered by concurrent ZDV use, but not by concurrent 3TC use. These data may have important implications for the efficacy of subsequent lines of NRTI therapies.

The final chapter of H. G. Wells's novel, Tono-Bungay (1909) has given rise to surprisingly wide differences of opinion among commentators. Geoffrey West, an early admirer of the novel, thought that 'in the last chapter, one of the most splendid passages Wells has ever written, is focused the whole spirit of the book';1 more recently J. R. Hammond referred to the chapter's 'series of brilliant images' and considered it 'one of the most carefully written ... in the whole corpus of [Wells's] fiction'.2 At the opposite extreme from these views is Mark Schorer's familiar dismissal of TonoBungay in his essay 'Technique as Discovery' (1948) and his condemnation of the final chapter as a 'significant failure' because it is merely 'a kind of meditative rhapsody which denies every value that the book has been aiming towards'.3 Even more severe than Schorer's criticism was Walter Allen's opinion that the chapter was 'one of Wells's shoddiest and most careless pieces of writing' in a generally muddled novel.4 In this final chapter George Ponderevo brings his story full circle by once more depicting himself in the act of writing it, and then expands on his new career of ship-designer by describing the seatrials of an experimental destroyer, the X2. This brief episode ends the novel. In addition to the stylistic and structural aspects of the chapter, the sudden appearance of the X2 has also puzzled critics. Although there are brief references to this vessel earlier in the novel, the X2 seems something of an after-thought, mainly because George gives no account of how he came to his new occupation of designing warships. Moreover, George himself seems uncertain what 'the value of a thing at once so essential and so immaterial' might be.5

Summary: Polydactylous squamous cell carcinoma (SCC) is rare and has been associated with human papillomavirus (HPV). Our recent case was HPV negative and provides greater evidence for chemical irritants being an alternative cause of subungual SCC. Our patient had spent a number of years with her hands in direct contact with undiluted cleaning chemicals including one containing ethanolamine. Ethanolamine has been shown to have carcinogen sensitizing role. Although HPV has a strong association with subungual SCCs, the accumulation and concentration of noxious substances around and under the nails must also be considered as a potential cause.

A scheme for obtaining strain maps from a set of MRI scans of the heart is presented. Using a technique known as the Spatial Modulation of Magnetization a set of MRI scans are generated with tag-lines distributed over the walls of the heart. As the heart moves, these tag-lines will move accordingly. Active contours or snakes are then used to extract the tag-lines from each MRI image, and the motion of the tag-lines determined. Laplacian smoothing splines are then used to estimate the displacement of points between the tag-lines. The strain experienced through out the heart is then a simple function of the associated displacement. Regional strain analysis is of vital importance in diagnosing different forms of heart disease, such as myocardial infarction or ``heart attack''. The method presented in this paper makes the analysis of cardiac strain feasible.

To assess the comparative effectiveness of relaxation instructions and frontalis electromyographic (EMG) biofeedback in the treatment of muscle-contraction (tension) headaches, 21 volunteers were assigned to either a relaxation training group, a biofeedback group or a no-treatment control group. Each group met for six 1/2-hr sessions. The EMG biofeedback and the relaxation instructions resulted in significant decreases in reported headache activity. Both procedures were significantly more effective than the control procedure, but did not differ significantly from each other in effectiveness. The effectiveness of the two experimental procedures was maintained at follow-up. Frontalis EMG levels were higher during sessions in which a headache was reported than in sessions when no headache was reported. The importance of individual differences is emphasized.