8,112 research outputs found

    Virtual audio reproduced in a headrest

    No full text
    When virtual audio reproduction is simultaneously required in many seats, such as in aircraft or cinemas, it may be convenient to use loudspeakers mounted inside each seat's headrest. In this preliminary study, the feasibility of virtual audio reproduction in the headrest of a single seat is explored using an inversion technique to compensate for crosstalk and the synthesis of head related transfer functions. Although large changes in the magnitude of the signals reproduced at the listener's ears are observed as the listener moves their head within the headrest, informal listening tests indicate that the reproduced acoustic images are surprisingly stable in about an eighth of an arc either side of the loudspeaker positions. Not surprisingly, frontal images are more difficult to reproduce with headrest loudspeakers

    Renal fibrosis in feline chronic kidney disease: known mediators and mechanisms of injury

    Get PDF
    Chronic kidney disease (CKD) is a common medical condition of ageing cats. In most cases the underlying aetiology is unknown, but the most frequently reported pathological diagnosis is renal tubulointerstitial fibrosis. Renal fibrosis, characterised by extensive accumulation of extra-cellular matrix within the interstitium, is thought to be the final common pathway for all kidney diseases and is the pathological lesion best correlated with function in both humans and cats. As a convergent pathway, renal fibrosis provides an ideal target for the treatment of CKD and knowledge of the underlying fibrotic process is essential for the future development of novel therapies. There are many mediators and mechanisms of renal fibrosis reported in the literature, of which only a few have been investigated in the cat. This article reviews the process of renal fibrosis and discusses the most commonly cited mediators and mechanisms of progressive renal injury, with particular focus on the potential significance to feline CKD

    Effect of praziquantel treatment of Schistosoma mansoni during pregnancy on immune responses to schistosome antigens among the offspring: results of a randomised, placebo-controlled trial.

    Get PDF
    BACKGROUND: Offspring of women with schistosomiasis may exhibit immune responsiveness to schistosomes due to in utero sensitisation or trans-placental transfer of antibodies. Praziquantel treatment during pregnancy boosts maternal immune responses to schistosome antigens and reduces worm burden. Effects of praziquantel treatment during pregnancy on responses among offspring are unknown. METHODS: In a trial of anthelminthic treatment during pregnancy in Uganda (ISRCTN32849447; http://www.controlled-trials.com/ISRCTN32849447/elliott), offspring of women with Schistosoma mansoni were examined for cytokine and antibody responses to schistosome worm (SWA) and egg (SEA) antigen, in cord blood and at age one year. Relationships to maternal responses and pre-treatment infection intensities were examined, and responses were compared between the offspring of women who did, or did not receive praziquantel treatment during pregnancy. RESULTS: Of 388 S. mansoni-infected women studied, samples were obtained at age one year from 215 of their infants. Stool examination for S. mansoni eggs was negative for all infants. Cord and infant samples were characterised by very low cytokine production in response to schistosome antigens with the exception of cord IL-10 responses, which were substantial. Cord and infant cytokine responses showed no association with maternal responses. As expected, cord blood levels of immunoglobulin (Ig) G to SWA and SEA were high and correlated with maternal antibodies. However, by age one year IgG levels had waned and were hardly detectable. Praziquantel treatment during pregnancy showed no effect on cytokine responses or antibodies levels to SWA or SEA either in cord blood or at age one year, except for IgG1 to SWA, which was elevated in infants of treated mothers, reflecting maternal levels. There was some evidence that maternal infection intensity was positively associated with cord blood IL-5 and IL-13 responses to SWA, and IL-5 responses to SEA, and that this association was modified by treatment with praziquantel. CONCLUSIONS: Despite strong effects on maternal infection intensity and maternal immune responses, praziquantel treatment of infected women during pregnancy had no effect on anti-schistosome immune responses among offspring by age one year. Whether the treatment will impact upon the offspring's responses on exposure to primary schistosome infection remains to be elucidated. TRIAL REGISTRATION: ISRCTN: ISRCTN32849447

    Attenuation of FJ44 Turbofan Engine Noise with a Foam-Metal Liner Installed Over-the-Rotor

    Get PDF
    A Williams International FJ44-3A 3000-lb thrust class turbofan engine was used as a demonstrator for a Foam-Metal Liner (FML) installed in close proximity to the fan. Two FML designs were tested and compared to the hardwall baseline. Traditional single degree-of-freedom liner designs were also evaluated to provide a comparison. Farfield acoustic levels and limited engine performance results are presented in this paper. The results show that the FML achieved up to 5 dB Acoustic Power Level (PWL) overall attenuation in the forward quadrant, equivalent to the traditional liner design. An earlier report presented the test set-up and conditions

    UK quality statements on end of life care in dementia: a systematic review of research evidence

    Get PDF
    BACKGROUND: Globally, the number of people who die with dementia is increasing. The importance of a palliative approach in the care of people with dementia is recognised and there are national polices to enhance current care. In the UK implementation of these polices is promoted by the National Institute for Health and Care Excellence (NICE) Dementia Quality Standards (QS). Since publication of the QS new care interventions have been developed. AIM: To explore critically the current international research evidence on effect available to inform NICE Dementia QS relevant to end of life (EOL) care. DESIGN: We used systematic review methods to seek the research evidence for three statements within the Dementia QS. These are those that recommend: (1) a case management approach, (2) discussing and consideration of making a statement about future care (SFC) and (3) a palliative care assessment (PCA). We included evaluative studies of relevant interventions that used a comparative design, such as trials and cohort studies, and measured EOL care outcomes for persons dying with moderate to severe dementia. Our primary outcome of interest was whether the intervention led to a measurable impact on wellbeing for the person with dementia and their family. We assessed included studies for quality using a scale by Higginson and colleagues (2002) for assessment of quality of studies in palliative care, and two authors undertook key review processes. Data sources included Cinahl, Embase, and PsychINFO from 2001 to August 2014. Our search strategy included free text and medical subject headings relevant to population and recommended care. RESULTS: We found seven studies evaluating a care intervention; four assessed SFC, three PCA. None assessed case management. Studies were of weak design; all used retrospective data and relied on others for precise record keeping and for accurate recall of events. There was limited overlap in outcome measurements. Overall reported benefits were mixed. CONCLUSIONS: Quality statements relevant to EOL care are useful to advance practice however they have a limited evidence base. High quality empirical work is needed to establish that the recommendations in these statements are best practice

    T. brucei cathepsin-L increases arrhythmogenic sarcoplasmic reticulum-mediated calcium release in rat cardiomyocytes

    Get PDF
    Aims: African trypanosomiasis, caused by Trypanosoma brucei species, leads to both neurological and cardiac dysfunction and can be fatal if untreated. While the neurological-related pathogenesis is well studied, the cardiac pathogenesis remains unknown. The current study exposed isolated ventricular cardiomyocytes and adult rat hearts to T. brucei to test whether trypanosomes can alter cardiac function independent of a systemic inflammatory/immune response. Methods and results: Using confocal imaging, T. brucei and T. brucei culture media (supernatant) caused an increased frequency of arrhythmogenic spontaneous diastolic sarcoplasmic reticulum (SR)-mediated Ca2+ release (Ca2+ waves) in isolated adult rat ventricular cardiomyocytes. Studies utilising inhibitors, recombinant protein and RNAi all demonstrated that this altered SR function was due to T. brucei cathepsin-L (TbCatL). Separate experiments revealed that TbCatL induced a 10–15% increase of SERCA activity but reduced SR Ca2+ content, suggesting a concomitant increased SR-mediated Ca2+ leak. This conclusion was supported by data demonstrating that TbCatL increased Ca2+ wave frequency. These effects were abolished by autocamtide-2-related inhibitory peptide, highlighting a role for CaMKII in the TbCatL action on SR function. Isolated Langendorff perfused whole heart experiments confirmed that supernatant caused an increased number of arrhythmic events. Conclusion: These data demonstrate for the first time that African trypanosomes alter cardiac function independent of a systemic immune response, via a mechanism involving extracellular cathepsin-L-mediated changes in SR function

    An Evaluability Assessment of the West Virginia Physical Activity Plan, 2015: Lessons Learned for Other State Physical Activity Plans

    Get PDF
    Background The US National Physical Activity Plan (NPAP) was released in 2009 as a national strategic plan to increase physical activity (PA). The NPAP emphasized implementing state and local PA pro- grams. Dissemination of information about NPAP has been lim- ited, however. Community Context West Virginia is a predominantly rural state with high rates of chronic diseases associated with physical inactivity. In 2015 an evaluability assessment (EA) of the West Virginia Physical Activ- ity Plan (WVPAP) was conducted, and community stakeholders were invited to participate in updating the plan. Methods A good EA seeks stakeholder input, assists in identifying program areas that need improvement, and ensures that a full evaluation will produce useful information. Data for this EA were collected via national stakeholder interviews, document reviews, discussions among workgroups consisting of state and local stakehold- ers, and surveys to determine how well the WVPAP had been im- plemented. Outcome The EA highlighted the need for WVPAP leaders to 1) establish a specific entity to implement local PA plans, 2) create sector-spe- cific logic models to simplify the WVPAP for local stakeholders, 3) evaluate the PA plan’s implementation frequently from the out- set, 4) use quick and efficient engagement techniques with stake- holders when working with them to select strategies, tactics, and measurable outcomes, and 5) understand the elements necessary to implement, manage, and evaluate a good PA plan. Interpretation An EA process is recommended for other leaders of PA plans. Our project highlights the stakeholders’ desire to simplify the WVPAP so that it can be set up as a locally driven process that engages communities in implementation

    Muscular Strength and Body Composition Comparison Between the Charlotte-Mecklenburg Fire and Police Departments

    Get PDF
    Firefighters and police have different physical job requirements and selection processes. Firefighters have on-duty exercise time and police do not. This could affect body composition and strength. The purpose of this investigation was to compare body composition and bench press strength between firefighters and police officers in the Charlotte-Mecklenburg departments. Current 2006 fitness records were analyzed to compare firefighters and police (N = 2330). Variables included: gender, age, body mass, percent body-fat, fat mass, lean mass, bench press strength, bench press/lean mass, bench press/body mass, and percent that were obese. Significant (p ≤ 0.05) differences were found between male firefighters and police in age (37.7 vs. 36.9 yrs), body mass (91.5 vs. 93.2 kg), percent body-fat (17.8% vs.18.5%), fat mass (16.9 vs. 18.0 kg), bench press strength (93.4 vs. 96.3 kg), bench press/body mass (1.03 vs.1.05) and percent that were obese (10% vs.17%), respectively. Significant differences between female firefighters and police were found in age (42.4 vs. 37.4 yrs), body mass (77.5 vs. 71.8 kg), lean mass (54.4 vs. 51.2 kg), bench press strength (52.3 vs. 43.9 kg), bench press/lean mass (0.99 vs. 0.86) and bench press/body mass (0.69 vs. 0.62), respectively. Male police were younger, weighed more, had higher percent body fat, higher percent of obesity, and had greater upper body strength than firefighters. Female police were younger, weighed less, had less lean mass and less upper body strength than their firefighter counterparts. Contributing factors might include pre-employment selection, recruit training, in-service physical fitness testing, and counseling provided by departments

    Spatial and Temporal Distribution of Imidacloprid Within the Crown of Eastern Hemlock

    Get PDF
    Systemic imidacloprid is the most widely used insecticide to control the hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), an exotic pest of eastern hemlock, Tsuga canadensis (L.) Carriére in the United States. This study was conducted to 1) determine the effect of treatment timing (spring vs. fall) and application method (trunk injection vs. soil injection) on the spatial and temporal distribution of imidacloprid within the crown of A. tsugae-free eastern hemlock using a competitive enzyme-linked immunosorbent assay (ELISA), 2) compare ELISA to gas chromatography-mass spectrometry (GC/MS) for the detection of imidacloprid in xylem fluid, and 3) determine the concentration of imidacloprid in leaf tissue using high performance liquid chromatography with tandem mass spectrometric (LC/MS/MS) detection methods. Xylem fluid concentrations of imidacloprid were found to be significantly higher for spring applications than for fall applications and for trunk injections than soil injections in the first year posttreatment. A total of 69% of samples analyzed by ELISA gave 1.8 times higher concentrations of imidacloprid than those found by GC/MS, leading to evidence of a matrix effect and overestimation of imidacloprid in xylem fluid by ELISA. A comparison of the presence of imidacloprid with xylem fluid and in leaf tissue on the same branch showed significant differences, suggesting that imidacloprid moved intermittently within the crown of eastern hemlock

    Reactions of organoboranes with carbanions bearing three potential leaving groups: unusual processes, products and mechanisms

    Get PDF
    Known reagents that transfer three alkyl groups of a trialkylborane intramolecularly to a single carbon atom lack features to influence stereochemistry. We have investigated four reagents of type LiCCl2X, where X might be amenable to variation. All behaved differently. With X=OR (R=cyclohexyl, menthyl), the reagent decomposed, leading to only low yields of triple migration products. With X=S(O)Ph, a single migration occurred, followed by isomerisation to boron enolate-like species that hydrolysed to α-chloroalkyl phenyl sulfoxides or reacted with aldehydes to aldol-like products. With X=SO2Ph, the major product was the corresponding α,α-dichloroalkyl phenyl sulfone, apparently formed through a redox reaction. With X=S(O)(NMe)Ph, products of three intramolecular alkyl migrations were obtained with unhindered trialkylboranes. Attempts have been made to gain understanding of the sulfoxide process by investigating proportions of aldol-like products, using X-ray crystallography and ab initio calculations
    • …
    corecore