Virtual Animals as Diegetic Attention Guidance Mechanisms in 360-Degree Experiences.

360-degree experiences such as cinematic virtual reality and 360-degree videos are becoming increasingly popular. In most examples, viewers can freely explore the content by changing their orientation. However, in some cases, this increased freedom may lead to viewers missing important events within such experiences. Thus, a recent research thrust has focused on studying mechanisms for guiding viewers' attention while maintaining their sense of presence and fostering a positive user experience. One approach is the utilization of diegetic mechanisms, characterized by an internal consistency with respect to the narrative and the environment, for attention guidance. While such mechanisms are highly attractive, their uses and potential implementations are still not well understood. Additionally, acknowledging the user in 360-degree experiences has been linked to a higher sense of presence and connection. However, less is known when acknowledging behaviors are carried out by attention guiding mechanisms. To close these gaps, we conducted a within-subjects user study with five conditions of no guide and virtual arrows, birds, dogs, and dogs that acknowledge the user and the environment. Through our mixed-methods analysis, we found that the diegetic virtual animals resulted in a more positive user experience, all of which were at least as effective as the non-diegetic arrow in guiding users towards target events. The acknowledging dog received the most positive responses from our participants in terms of preference and user experience and significantly improved their sense of presence compared to the non-diegetic arrow. Lastly, three themes emerged from a qualitative analysis of our participants' feedback, indicating the importance of the guide's blending in, its acknowledging behavior, and participants' positive associations as the main factors for our participants' preferences.

A workforce in jeopardy: identifying the challenges of ensuring a sustainable advanced HIV nursing workforce.

BACKGROUND: HIV services in England face substantial challenges arising from financial pressures and changes to commissioning. A sustainable HIV specialist nursing workforce will be vital to enable them to respond to those challenges. AIMS: This paper examines the current workforce situation in HIV services across the country. METHODS: This mixed-method study involved semi-structured interviews with 19 key stakeholders and with 44 nurses/physicians from 21 purposively selected HIV services across England. Data were interpreted using a framework analysis approach. RESULTS: 'Building a career in HIV nursing' identified problems associated with retention and recruitment. Changes in commissioning are disrupting common career routes from sexual health to HIV nursing, and a perceived lack of a clear career pathway was seen as a barrier to recruitment. 'Developing a specialist workforce' explored the professional development of the current workforce, which was hampered by poor access to funding or study time for advanced study and the absence of an HIV-specific advanced nursing qualification. CONCLUSIONS: The HIV nursing workforce, which provides an increasing proportion of HIV care, is facing serious recruitment and retention challenges. A strategic approach to workforce development and training is essential to overcome systemic barriers and secure the next generation of skilled practitioners.

How does specialist nursing contribute to HIV service delivery across England?

This study aimed to examine what specialist nursing contributes to HIV service delivery across England and how it could be optimised. A three part multi-method qualitative study was undertaken, involving (1) interviews with 19 stakeholders representing professional or service user groups; (2) interviews with nurse/physician pairs from 21 HIV services; and (3) case studies involving site visits to five services. A framework analysis approach was used to manage and analyse the data. There was substantial variability in specialist nursing roles and the extent of role development. Most hospital-based HIV nurses (13/19) were running nurse-led clinics, primarily for stable patients with almost half (6/13) also managing more complex patients. Role development was supported by non-medical prescribing, a robust governance framework and appropriate workload allocation. The availability and organisation of community HIV nursing provision determined how services supported vulnerable patients to keep them engaged in care. Four service models were identified. The study showed that there is scope for providing a greater proportion of routine care through nurse-led clinics. HIV community nursing can influence health outcomes for vulnerable patients, but provision is variable. With limited financial resources, services may need to decide how to deploy their specialist nurses for best effect.

Sudden death, aortic rupture in horses, literature review, case studies reported and risk factors / Morte súbita por ruptura da aorta em cavalos, literatura, estudos de casos relatados e fatores de risco

Sudden deaths of horses in multiple equestrian disciplines have been attributed to acute and chronic respiratory and cardiovascular diseases. The aim of this study was to perform a review of aortic rupture in horses analyzing, case studies and assessing risk factors. The literature has reported a total of 137 cases of aortic rupture in horses for 28 years (1986-2014), with approximately five horses dying of aortic rupture per year. Histopathologically, there are observed discrete macroscopic degenerative changes in the intima layer only in the aorta. The histological evaluation in the beginning portion of the aorta of the heart evidenced degenerative changes with loss of continuity and distribution of elastic fibers. Risk factors for the rupture of the aorta are: spontaneous rupture associated with hypertension, preexisting vascular injury (aneurysm), dilated or hypertrophic cardiomyopathy, copper levels in the endothelium, genetic factors such as inbreeding, toxicology or pharmacological factors. Aortic rupture shows similarity with pulmonary hemorrhage induced by exercise especially under the locomotors induced trauma theory of exercise that can induce pulmonary hemorrhage. In conclusion, degenerative changes to discrete elastic fiber of the intima of the aorta in the emergence of the heart seem to predispose the aorta wall rupture at the time of maximum blood pressure during exercise and the consequent collapse and athletic horses death...

As mortes súbitas de cavalos em várias provas equestres têm sido atribuídas a doenças respiratórias e cardiovasculares agudas e crônicas. O objetivo deste estudo foi efetuar uma revisão de literatura da ruptura da aorta em cavalos analisando estudos de caso e estabelecendo os possíveis fatores de risco. Na revisão da literatura no período de 28 anos (1986-2014) foram localizados 137 casos de ruptura da aorta em cavalos com aproximadamente cinco cavalos morrendo por essa causa por ano. Histologicamente, são observadas alterações macroscópicas discretas degenerativas na camada íntima da aorta. A avaliação histológica na porção inicial da aorta do coração evidencia alterações degenerativas com perda de continuidade e distribuição das fibras elásticas. Fatores de risco para a ruptura da aorta dos cavalos são: ruptura espontânea associada com hipertensão, lesão vascular pré-existente (aneurisma), cardiomiopatia dilatada ou hipertrófica, níveis de cobre no endotélio, fatores genéticos, tais como a consanguinidade na criação, toxicologia e aspectos farmacológicos. A ruptura aórtica mostra semelhança com hemorragia pulmonar induzida pelo exercício. Em conclusão, alterações degenerativas discretas das fibras elásticas da íntima da aorta parecem predispor a ruptura da parede da aorta, no momento da pressão máxima de sangue durante o exercício determinando o consequente colapso e morte do cavalo atleta...

People with learning disabilities are hit hard by funding cutbacks.

Thank you for publishing Ken Mack's letter (March 5) drawing attention to the suffering and distress caused by welfare reforms and cutbacks, and how people with disabilities and their families are being hit particularly hard.

Scopolamine in racing horses: trace identifications associated with dietary or environmental exposure.

Scopolamine (L-hyoscine) identifications, often in small-number clusters, have been reported worldwide in performance horses over the last 30 years. Scopolamine is an Association of Racing Commissioners International (ARCI) class 3, penalty class B, substance with potential to affect performance. As such, scopolamine identification(s) in race or performance horses can result in significant penalties for the connections of the horse(s). Reviewed here is the worldwide distribution of scopolamine containing plants (primarily Datura spp.), with estimates of their potential toxicity to horses through dietary and/or environmental exposure. Also reviewed are the basic pharmacology of scopolamine and its precursor, urinary concentrations following feedstuff exposure, and the probable pharmacological/forensic significance of such findings. Based on an overview of the world literature on scopolamine, the expected characteristics of inadvertent environmental exposure are also presented with a view to making clear the potential of scopolamine identifications, with or without atropine, as a direct and expected outcome of both the worldwide distribution of scopolamine-containing plants and the sensitivity of modern equine drug testing. It is of particular interest that only 2/30 reported post-event equine identifications of scopolamine have been associated with atropine, suggesting that failure to identify atropine is not a biomarker of pharmaceutical administration of scopolamine. Available quantitative information associated with scopolamine identifications is consistent with the 75 ng/mL regulatory threshold for scopolamine currently used in Louisiana racing in the USA and the 30 ng/mL reporting threshold in effect in European racing.

The contribution of the HIV specialist nurse to HIV care: a scoping review.

AIMS AND OBJECTIVES: To systematically identify and critically examine the evidence of the contribution of the HIV nurse specialist to provision of HIV care in the UK and other developed countries. BACKGROUND: The HIV clinical nurse specialist role has evolved over the past two decades in response to changes in two areas of HIV care: first, changes in the treatment and care of those with HIV and second, changes and development in advanced nursing practice. The challenges facing HIV care require the development of innovative services including a greater contribution of HIV specialist nurses. A review of current evidence is required to inform developments. DESIGN: A review. METHODS: A broad search strategy was used to search electronic databases. Grey literature was accessed through a variety of approaches. Preference was given to UK literature with inclusion of international publications from other developed countries where relevant. RESULTS: Fourteen articles were included. Four themes were identified: the diversity of the clinical role; a knowledge and skills framework for HIV nursing practice; the education and training role of the HIV nurse specialist; and the effectiveness of the HIV nurse specialist. The findings mainly focus on the clinical aspects of the role with little evidence concerning other aspects. There is limited evidence to indicate clinical effectiveness. CONCLUSIONS: HIV care is facing substantial challenges, and there is a clear need to develop effective and efficient services, including expanding the contribution of HIV nurse specialists. Such developments need to occur within a framework that optimises nursing contribution and measures their impact on HIV care. This review provides a baseline to inform such developments. RELEVANCE TO CLINICAL PRACTICE: This review of the literature details current understanding of the role of HIV specialist nurses and the contribution that they make to HIV care.

A clinician's guide to factors affecting withdrawal times for equine therapeutic medications.

Equine forensic science can now detect concentrations down to 25 femtograms/mL (parts per quadrillion, ppq) or less in blood and urine. As such, horsemen are increasingly at risk of inadvertent 'positives' due to therapeutic medication 'overages' or trace identifications of dietary or environmental substances. Reviewed here are the factors which determine detection times and 'withdrawal times' for substances administered to horses. Withdrawal times are affected by many factors, including dose, formulation, route and frequency of administration, bioavailability, plasma half-life, sensitivity of the analytical process, the testing matrix (plasma, urine, or other), and the environmental presence and/or persistence of administered substances. Of these factors only dose is known precisely. For any given administration, horse-to-horse differences in the volumes of distribution, systemic clearance, and terminal plasma elimination half-life of substances are major and totally uncontrollable factors driving horse-to-horse variability in withdrawal times. A further complication is that chemically stable medications administered to horses and eliminated in the urine inevitably become part of the environment of the horse. The presence of these substances in the equine environment is increasingly giving rise to trace identifications long after nominal administration of these substances has ceased. Because of the unknown and uncontrollable horse-to-horse variability in medication pharmacokinetics, any therapeutic medication administration to a horse by definition includes the possibility of an inadvertent medication overage. As such, the caveat that there are no guarantees in life most assuredly applies to advisories concerning equine therapeutic medication withdrawal times.

New therapeutic approaches for equine protozoal myeloencephalitis: pharmacokinetics of diclazuril sodium salts in horses.

Diclazuril is a triazine-based antiprotozoal agent which may have clinical application in the treatment of equine protozoal myeloencephalomyelitis (EPM). In this study, the use of the sodium salt diclazuril to increase the apparent bioavailability of diclazuril for the treatment and prophylaxis of EPM and various other Apicomplexan mediated diseases is described. In this study, diclazuril sodium salt was synthesized and administered to horses as diclazuril sodium salt formulations. The absorption, distribution, and clearance of diclazuril sodium salt in the horse are described. Diclazuril was rapidly absorbed, with peak plasma concentrations occurring at 8-24 hours following an oral mucosal administration of diclazuril sodium salt. The mean oral bioavailability of diclazuril as Clinacox was 9.5% relative to oral mucosal administration of diclazuril sodium salt. Additionally, diclazuril in DMSO administered orally was 50% less bioavailable than diclazuril sodium salt following an oral mucosal administration. It was also shown that diclazuril sodium salt has the potential to be used as a feed additive for the treatment and prophylaxis of EPM and various other Apicomplexan mediated diseases.

The detection and biotransformation of guanabenz in horses: a preliminary report.

Guanabenz (2,6-dichlorobenzylidene-amino-guanidine) is a centrally acting antihypertensive drug whose mechanism of action is via alpha2 adrenoceptors or, more likely, imidazoline receptors. Guanabenz is marketed as an antihypertensive agent in human medicine (Wytensin tablets, Wyeth Pharmaceuticals). Guanabenz has reportedly been administered to racing horses and is classified by the Association of Racing Commissioners International as a class 3 foreign substance. As such, its identification in a postrace sample may result in significant sanctions against the trainer of the horse. The present study examined liquid chromatographic/tandem quadrupole mass spectrometric (LC-MS/MS) detection of guanabenz in serum samples from horses treated with guanabenz by rapid i.v. injection at 0.04 and 0.2 mg/kg. Using a method adapted from previous work with clenbuterol, the parent compound was detected in serum with an apparent limit of detection of approximately 0.03 ng/ml and the limit of quantitation was 0.2 ng/ml. Serum concentrations of guanabenz peaked at approximately 100 ng/ml after the 0.2 mg/kg dose, and the parent compound was detected for up to 8 hours after the 0.04 mg/kg dose. Urine samples tested after administration of guanabenz at these dosages yielded evidence of at least one glucuronide metabolite, with the glucuronide ring apparently linked to a ring hydroxyl group or a guanidinium hydroxylamine. The LC-MS/MS results presented here form the basis of a confirmatory test for guanabenz in racing horses.

The toxicokinetics of cyanide and mandelonitrile in the horse and their relevance to the mare reproductive loss syndrome.

The epidemiological association between black cherry trees and mare reproductive loss syndrome has focused attention on cyanide and environmental cyanogens. This article describes the toxicokinetics of cyanide in horses and the relationships between blood cyanide concentrations and potentially adverse responses to cyanide. To identify safe and humane blood concentration limits for cyanide experiments, mares were infused with increasing doses (1-12 mg/min) of sodium cyanide for 1 h. Infusion at 12 mg/min produced clinical signs of cyanide toxicity at 38 min; these signs included increased heart rate, weakness, lack of coordination, loss of muscle tone, and respiratory and behavioral distress. Peak blood cyanide concentrations were about 2500 ng/mL; the clinical and biochemical signs of distress reversed when infusion stopped. Four horses were infused with 1 mg/min of sodium cyanide for 1 h to evaluate the distribution and elimination kinetics of cyanide. Blood cyanide concentrations peaked at 1160 ng/mL and then declined rapidly, suggesting a two-compartment, open model. The distribution (alpha) phase half-life was 0.74 h, the terminal (beta phase) half-life was 16.16 h. The mean residence time was 12.4 h, the steady-state volume of distribution was 2.21 L/kg, and the mean systemic clearance was 0.182 L/h/kg. Partitioning studies showed that blood cyanide was about 98.5% associated with the red cell fraction. No clinical signs of cyanide intoxication or distress were observed during these infusion experiments. Mandelonitrile was next administered orally at 3 mg/kg to four horses. Cyanide was rapidly available from the orally administered mandelonitrile and the C max blood concentration of 1857 ng/mL was observed at 3 min after dosing; thereafter, blood cyanide again declined rapidly, reaching 100 ng/mL by 4 h postadministration. The mean oral bioavailability of cyanide from mandelonitrile was 57% +/- 6.5 (SEM), and its apparent terminal half-life was 13 h +/- 3 (SEM). No clinical signs of cyanide intoxication or distress were observed during these experiments. These data show that during acute exposure to higher doses of cyanide (~600 mg/horse; 2500 ng/mL of cyanide in blood), redistribution of cyanide rapidly terminated the acute toxic responses. Similarly, mandelonitrile rapidly delivered its cyanide content, and acute cyanide intoxications following mandelonitrile administration can also be terminated by redistribution. Rapid termination of cyanide intoxication by redistribution is consistent with and explains many of the clinical and biochemical characteristics of acute, high-dose cyanide toxicity. On the other hand, at lower concentrations (<100 ng/mL in blood), metabolic transformation of cyanide is likely the dominant mechanism of termination of action. This process is slow, with terminal half-lives ranging from 12-16 hours. The large volume of distribution and the long terminal-phase-elimination half-life of cyanide suggest different mechanisms for toxicities and termination of toxicities associated with low-level exposure to cyanide. If environmental exposure to cyanide is a factor in the cause of MRLS, then it is likely in the more subtle effects of low concentrations of cyanide on specific metabolic processes that the associations will be found.

A simple and highly sensitive spectrophotometric method for the determination of cyanide in equine blood.

An epidemiological association among black cherry trees (Prunus serotina), eastern tent caterpillars (Malacosoma americana), and the spring 2001 episode of mare reproductive loss syndrome in central Kentucky focused attention on the potential role of environmental cyanogens in the causes of this syndrome. To evaluate the role of cyanide (CN (-)) in this syndrome, a simple, rapid, and highly sensitive method for determination of low parts per billion concentrations of CN (-) in equine blood and other biological fluids was developed. The analytical method is an adaptation of methods commonly in use and involves the evolution and trapping of gaseous hydrogen cyanide followed by spectrophotometric determination by autoanalyzer. The limit of quantitation of this method is 2 ng/mL in equine blood, and the standard curve shows a linear relationship between CN (-) concentration and absorbance (r >. 99). The method throughput is high, up to 100 samples per day. Normal blood CN (-) concentrations in horses at pasture in Kentucky in October 2001 ranged from 3-18 ng/mL, whereas hay-fed horses showed blood CN (-) levels of 2-7 ng/mL in January 2002. Blood samples from a small number of cattle at pasture showed broadly similar blood CN (-) concentrations. Intravenous administration of sodium cyanide and oral administration of mandelonitrile and amygdalin yielded readily detectable increases in blood CN (-) concentrations. This method is sufficiently sensitive and specific to allow the determination of normal blood CN (-) levels in horses, as well as the seasonal and pasture-dependent variations. The method should also be suitable for investigation of the toxicokinetics and disposition of subacutely toxic doses of CN (-) and its precursor cyanogens in the horse as well as in other species.

The mare reproductive loss syndrome and the eastern tent caterpillar: a toxicokinetic/statistical analysis with clinical, epidemiologic, and mechanistic implications.

During 2001, central Kentucky experienced acute transient epidemics of early and late fetal losses, pericarditis, and unilateral endophthalmitis, collectively referred to as mare reproductive loss syndrome (MRLS). A toxicokinetic/statistical analysis of experimental and field MRLS data was conducted using accelerated failure time (AFT) analysis of abortions following administration of Eastern tent caterpillars (ETCs; 100 or 50 g/day or 100 g of irradiated caterpillars/day) to late-term pregnant mares. In addition, 2001 late-term fetal loss field data were used in the analysis. Experimental data were fitted by AFT analysis at a high (P <.0001) significance. Times to first abortion ("lag time") and abortion rates were dose dependent. Lag times decreased and abortion rates increased exponentially with dose. Calculated dose x response data curves allow interpretation of abortion data in terms of "intubated ETC equivalents." Analysis suggested that field exposure to ETCs in 2001 in central Kentucky commenced on approximately April 27, was initially equivalent to approximately 5 g of intubated ETCs/day, and increased to approximately 30 g/day at the outbreak peak. This analysis accounts for many aspects of the epidemiology, clinical presentations, and manifestations of MRLS. It allows quantitative interpretation of experimental and field MRLS data and has implications for the basic mechanisms underlying MRLS. The results support suggestions that MRLS is caused by exposure to or ingestion of ETCs. The results also show that high levels of ETC exposure produce intense, focused outbreaks of MRLS, closely linked in time and place to dispersing ETCs, as occurred in central Kentucky in 2001. With less intense exposure, lag time is longer and abortions tend to spread out over time and may occur out of phase with ETC exposure, obscuring both diagnosis of this syndrome and the role of the caterpillars.

Detection, quantification, and pharmacokinetics of furosemide and its effects on urinary specific gravity following IV administration to horses.

Furosemide is a potent loop diuretic used for the prevention of exercise-induced pulmonary hemorrhage in horses. This drug may interfere with the detection of other substances by reducing urinary concentrations, so its use is strictly regulated. The regulation of furosemide in many racing jurisdictions is based on paired limits of urinary SG (<1.010) and serum furosemide concentrations (>100 ng/ml). To validate this regulatory mechanism, a liquid chromatography/mass spectrometry/mass spectrometry method employing a solid-phase extraction procedure and furosemide-d5 as an internal standard was developed. The method was used to determine the pharmacokinetic parameters of furosemide in equine serum samples and its effects on urinary SG after IV administration (250 mg) to 10 horses. Pharmacokinetic analysis showed that serum concentrations of furosemide were well described by a two-compartmental open model. Based on results in this study, it is very unlikely for horses to have serum furosemide concentrations greater than 100 ng/ml or urine SG less than 1.010 at 4 hours after administration (250 mg IV). However, it should be remembered that urine SG is a highly variable measurement in horses, and even without furosemide administration, some horses might naturally have urine SG values less than 1.010.

Detection, quantification, metabolism, and behavioral effects of selegiline in horses.

Selegiline ([R]-[-]N,alpha-dimethyl-N-2- propynylphenethylamine or l-deprenyl), an irreversible inhibitor of monoamine oxidase, is a classic antidyskinetic and antiparkinsonian agent widely used in human medicine both as monotherapy and as an adjunct to levodopa therapy. Selegiline is classified by the Association of Racing Commissioners International (ARCI) as a class 2 agent, and is considered to have high abuse potential in racing horses. A highly sensitive LC/MS/MS quantitative analytical method has been developed for selegiline and its potential metabolites amphetamine and methamphetamine using commercially available deuterated analogs of these compounds as internal standards. After administering 40 mg of selegiline orally to two horses, relatively low (<60 ng/ml) concentrations of parent selegiline, amphetamine, and methamphetamine were recovered in urine samples. However, relatively high urinary concentrations of another selegiline metabolite were found, tentatively identified as N- desmethylselegiline. This metabolite was synthesized and found to be indistinguishable from the new metabolite recovered from horse urine, thereby confirming the chemical identity of the equine metabolite. Additionally, analysis of urine samples from four horses dosed with 50 mg of selegiline confirmed that N-desmethylselegiline is the major urinary metabolite of selegiline in horses. In related behavior studies, p.o. and i.v. administration of 30 mg of selegiline produced no significant changes in either locomotor activities or heart rates.

Apparent ELISA detection times for albuterol after administration with the torpex equine inhaler device.

Single doses of one, three, and six actuations (120 micro g albuterol/actuation) and multiple daily doses (six actuations per dose four times daily) for 5 days of aerosol albuterol sulfate were sequentially administered to each of six horses using an equine inhaler device (Torpex, 3M Animal Care Products, St. Paul, MN [corrected] and Boehringer Ingleheim Vetmedica, Inc., St. Joseph, MO [corrected]). A 2-week washout period was allowed between each dose. ELISA testing revealed no evidence of albuterol in urine at 24 hours after any single-dose administration. Results indicated that 48 hours or longer should be allowed for albuterol to be cleared from urine after single doses. When given at the maximum recommended rate of six actuations per dose four times a day for 5 days, urine samples tested by ELISA showed no evidence of albuterol at 48 hours after the final dose. Testing of nasal swabs by ELISA demonstrated the presence of albuterol for 8 hours after each single dose, and some horses might have detectable levels of albuterol in nasal swabs for several days following administration of multiple doses. As a guideline for withdrawal time, 72 hours or longer should be allowed after administration of aerosol albuterol sulfate to horses before participation in equestrian competitions that are regulated for detection of certain performance-enhancing substances. However, these recommendations were based on a small sample of horses and the specific ELISA test used and interpreted as described. Factors specific to individual horses may influence these detection times.