Supercritical fuel injection system

a fuel injection system for gas turbines is described including a pair of high pressure pumps. The pumps provide fuel and a carrier fluid such as air at pressures above the critical pressure of the fuel. A supercritical mixing chamber mixes the fuel and carrier fluid and the mixture is sprayed into a combustion chamber. The use of fuel and a carrier fluid at supercritical pressures promotes rapid mixing of the fuel in the combustion chamber so as to reduce the formation of pollutants and promote cleaner burning

Gulf War Syndrome: A role for organophosphate induced plasticity of locus coeruleus neurons

Gulf War syndrome is a chronic multi-symptom illness that has affected about a quarter of the deployed veterans of the 1991 Gulf War. Exposure to prolonged low-level organophosphate insecticides and other toxic chemicals is now thought to be responsible. Chlorpyrifos was one commonly used insecticide. The metabolite of chlorpyrifos, chlorpyrifos oxon, is a potent irreversible inhibitor of acetylcholinesterase, much like the nerve agent Sarin. To date, the target brain region(s) most susceptible to the neuroactive effects of chlorpyrifos oxon have yet to be identified. To address this we tested ability of chlorpyrifos oxon to influence neuronal excitability and induce lasting changes in the locus coeruleus, a brain region implicated in anxiety, substance use, attention and emotional response to stress. Here we used an ex vivo rodent model to identify a dramatic effect of chlorpyrifos oxon on locus coeruleus noradrenergic neuronal activity. Prolonged exposure to chlorpyrifos oxon caused acute inhibition and a lasting rebound excitatory state expressed after days of exposure and subsequent withdrawal. Our findings indicate that the locus coeruleus is a brain region vulnerable to chlorpyrifos oxon-induced neuroplastic changes possibly leading to the neurological symptoms affecting veterans of the Gulf War

Cardiac Memory-induced T-wave Inversions

Introduction: Cardiac memory refers to T-wave inversions that result when normal ventricular activation resumes following a period of abnormal ventricular activation.Case Report: We present a case of a 29-year-old man with a pacemaker who presented with new, deep symmetric T-wave inversions caused by cardiac memory.Discussion: Abnormal ventricular activation is most commonly induced by ventricular pacing but can also occur in the setting of transient left bundle branch blocks, ventricular tachycardia, and intermittent ventricular pre-excitation.Conclusion: Recognition of this phenomenon may help to reduce unnecessary admissions, cardiac testing, and cardiac catheterizations

mGluR5 knockout mice exhibit normal conditioned place-preference to cocaine

Metabotropic glutamate receptor 5 (mGluR5) null mutant (-/-) mice have been reported to totally lack the reinforcing or locomotor stimulating effects of cocaine. We tested mGluR5 -/- and +/+ mice for their locomotor and conditioned place- preference response to cocaine. Unlike the previous finding, here we show that compared to mGluR5 +/+ mice, -/- mice exhibit no difference in the locomotor response to low to moderate doses of cocaine (10 or 20 mg/kg). A high dose of cocaine (40 mg/kg) resulted in a blunted rather than absent locomotor response. We tested mGluR5 -/- and +/+ mice for conditioned place-preference to cocaine and found no group differences at a conditioning dose of 10 mg/kg, suggesting normal conditioned rewarding properties of cocaine. These results differ substantially from Chiamulera et al. (2001) and replicates Olsen et al., (2010), who found normal cocaine place-preference in mGluR5 -/- mice at 5 mg/kg. Our results indicate mGluR5 receptors exert a modulatory rather than necessary role in cocaine-induced locomotor stimulation and exert no effect on the conditioned rewarding effects of cocaine

The joy of vacuuming? How the user experience affects vacuum cleaner longevity

An apparent reduction in the average lifetime of vacuum cleaners is explored in this paper in relation to their perceived usability and increasingly frequent product replacement. Motivations for product disposal combine perceived and real product failure with a perceived or real improved product offer. From an historical perspective, vacuum cleaners typify this pattern, continually offering a ‘cheaper and improved’ product. Vacuum cleaner manufacturers reinvigorate the sense of satisfaction and revulsion associated with extracting dirt from our homes through new performance focused product development. For example, increased motor power, filtration, bag-less machines and clear bin compartments have all acted as sales drivers, whilst cost effective materials and offshore and more efficient manufacturing have reduced purchase prices. The latter, cost-driven, processes can create machines that are more likely to be functionally and aesthetically damaged in use, reinforcing the trend for faster replacement. The market appears likely to continue to focus on improved user experience, with growth in market share for lighter weight cordless battery powered machines posing the risk of an increased environmental burden. Drawing from qualitative and quantitative research undertaken for a study for Defra, we explore the user’s relationship to the product, investigating the frustrations and joys of vacuum cleaner use and ownership. The findings illustrate that the revulsion and attraction of cleaning, as well as the tedium and satisfaction fostered by the product, have direct implications for vacuum cleaner longevity

What is broken? Expected lifetime, perception of brokenness and attitude towards maintenance and repair

This paper addresses the discrepancy between the expected and actual lifetimes of vacuum cleaners considering perceived ‘brokenness’ as a driver for replacement. Among electrical products, vacuum cleaners have a high rate of domestic ownership in the UK. They also embody large quantities of greenhouse gases which could be reduced by increasing their longevity and resource efficiency (Schreiber et al., 2012). A focus on energy efficiency has only shown limited or even negative results, therefore to meet recent European Union regulations on durability requirements a focus on product longevity is needed. Around one half of new vacuum cleaner purchasers replace one less than 5 years old, below the expected lifespan, with perceived breakage, poor performance and unreliability as the major reasons for replacement. Their relative simplicity could allow vacuum cleaners to last for significantly longer. The nature of the common causes of failure is known, including stretched cords or blockages, and WRAP has developed guidelines for product improvements. However, many working or repairable machines are disposed of because they are perceived to be ‘irremediably’ broken

The use of honey in healing a recalcitrant wound following surgical treatment of hidradenitis suppurativa

Ancient civilizations used honey to heal wounds. Despite the rediscovery of honey by modern physicians1 its use in conventional medicine, unlike in complementary medicine, remains limited. Much anecdotal evidence, some clinical observations, some animal models and some randomised controlled trials support the efficacy of honey in managing wounds2,3 , but few detailed descriptions of the use of honey in healing difficult surgical wounds have previously been published

Biocompatibility of a lab-on-a-pill sensor in artificial gastrointestinal environments

n this paper, we present a radiotelemetry sensor, designed as a lab-in-a-pill, which incorporates a two-channel microfabricated sensor platform for real-time measurements of temperature and pH. These two parameters have potential application for use in remote biological sensing (for example they may be used as markers that reflect the physiological environment or as indicators for disease, within the gastrointestinal tract). We have investigated the effects of biofouling on these sensors, by exploring their response time and sensitivity in a model in vitro gastrointestinal system. The artificial gastric and intestinal solutions used represent a model both for fasting, as well as for the ingestion of food and subsequent digestion to gastrointestinal chyme. The results showed a decrease in pH sensitivity after exposure of the sensors for 3 h. The response time also increased from an initial measurement time of 10 s in pure GI juice, to ca. 25 s following the ingestion of food and 80 s in simulated chyme. These in vitro results indicate that changes in viscosity in our model gastrointestinal system had a pronounced effect on the unmodified sensor