Body Orientation Affects the Perceived Size of Objects.

Here, we investigate how body orientation relative to gravity affects the perceived size of visual targets. When in virtual reality, participants judged the size of a visual target projected at simulated distances of between 2 and 10 m and compared it to a physical reference length held in their hands while they were standing or lying prone or supine. Participants needed to make the visual size of the target 5.4% larger when supine and 10.1% larger when prone, compared to when they were in an upright position to perceive that it matched the physical reference length. Needing to make the target larger when lying compared to when standing suggests some not mutually exclusive possibilities. It may be that while tilted participants perceived the targets as smaller than when they were upright. It may be that participants perceived the targets as being closer while tilted compared to when upright. It may also be that participants perceived the physical reference length as longer while tilted. Misperceiving objects as larger and/or closer when lying may provide a survival benefit while in such a vulnerable position.

The effect of training on the perceived approach angle in visual vertical heading judgements in a virtual environment.

Past studies have found poorer performance on vertical heading judgement accuracy compared to horizontal heading judgement accuracy. In everyday life, precise vertical heading judgements are used less often than horizontal heading judgements as we cannot usually control our vertical direction. However, pilots judging a landing approach need to consistently discriminate vertical heading angles to land safely. This study addresses the impact of training on participants' ability to judge their touchdown point relative to a target in a virtual environment with a clearly defined ground plane and horizon. Thirty-one participants completed a touchdown point estimation task twice, using three angles of descent (3°, 6° and 9°). In between the two testing tasks, half of the participants completed a flight simulator landing training task which provided feedback on their vertical heading performance; while, the other half completed a two-dimensional puzzle game as a control. Overall, participants were more precise in their responses in the second testing compared to the first (from a SD of ± 0.91° to ± 0.67°), but only the experimental group showed improvement in accuracy (from a mean error of - 2.1° to - 0.6°). Our results suggest that with training, vertical heading judgments can be as accurate as horizontal heading judgments. This study is the first to show the effectiveness of training in vertical heading judgement in naïve individuals. The results are applicable in the field of aviation, informing possible strategies for pilot training.

Price dispersion of generic medications.

Generic pharmaceuticals should have very little price dispersion. Economics' Law of One Price suggests that identical goods, in the absence of trade frictions and under conditions of free competition and price flexibility, should sell for the same price, and the FDA ensures that generics are identical. In this study, we examine whether generic pharmaceuticals indeed have the low price dispersion that theory predicts, and if not, whether the dispersion seen for pharmaceuticals used to treat neuropsychiatric conditions is substantially higher than that of other drugs. Such a difference may offer an explanation for the price dispersion seen: namely, a strategy that takes advantage of buyers' cognitive constraints and impaired ability to comparison shop. We thus assembled a list of generic pharmaceuticals and their prices using www.GoodRx.com, based on a convenience sample of the 5 most popular drugs for 10 common medical conditions listed there. Three neuropsychiatric diagnoses were used: Alzheimer's disease, depression and schizophrenia. Seven other diagnoses served as controls: asthma; diabetes mellitus-type II; high cholesterol; hypertension; osteoarthritis; osteoporosis; and urinary tract infection. For each drug, we identified the highest and lowest prices and calculated the mean, median and coefficient of variation (CV). We further calculated the ratios of the highest price to the median price and of the highest to lowest price. We found that the mean price CV was 43%. For neuropsychiatric drugs and controls, it was 61% and 35%, respectively. The mean high-to-median ratio was3.7 for neuropsychiatric drugs and 1.9 for controls. The mean high-to-low ratio was 5.9 for neuropsychiatric drugs and 2.8 for controls. In short, generic medications have high price dispersion, despite public availability of prices. Although our study did not examine why this price dispersion is present, the especially large high-to-low price ratio for neuropsychiatric medications suggests a strategy that exploits vulnerable patients.

Enhancing pharmaceutical crystallization in a flow crystallizer with ultrasound: Anti-solvent crystallization.

Continuous crystallization is a fast growing application domain in the pharmaceutical industry. Application of ultrasound has been proven to have positive effects like reduction in induction time and Metastable Zone Width (MSZW) in both batch and flow systems. Further understanding of flow-based sonocrystallization is required to achieve industrial level scale up. This work investigates the sonocrystallization of pharmaceutical compounds in a tubular flow crystallizer. Acetyl Salicylic Acid (ASA-Aspirin) is used as a model compound with ethanol and water as solvent and anti-solvent, respectively. Experiments were conducted in silent and sonicated conditions to study the MSZW. Ultrasound made it possible to achieve crystallization within the crystallizer which was not possible in silent conditions, under the tested conditions. Continuous crystallization was achieved at as low as 48 wt% of anti-solvent and crystallization was already seen at a supersaturation of 1.02. In some experiments, temperature rise with ultrasound caused the crystals to re-dissolve within the channels. Better crystallization - no re-dissolution - was achieved by using low ultrasonic power without any loss in the yield. Particle sizes of product crystals were in the range of 4-46 µm. In conclusion, ultrasound was highly effective in enabling anti-solvent crystallization of a pharmaceutical compound in a tubular flow crystallizer.

Implementation of a prioritized scoring tool to improve time to pharmacist intervention.

PURPOSE: The implementation of a prioritized scoring tool to improve time to pharmacist intervention is described. SUMMARY: At the Ohio State University Wexner Medical Center, pharmacists are accepted providers of therapeutic drug monitoring of vancomycin and aminoglycosides. At the onset of this initiative and despite the implementation of an integrated electronic medical record (EMR), management of pharmacokinetically monitored medications was conducted using a paper monitoring form. The potential for transcription errors during this process provided an opportunity for improvement. For these reasons, the department of pharmacy focused its initial efforts for a patient scoring system on the pharmacokinetics scoring module. Adjustment of associated medications based on pharmacokinetic values was a core function of pharmacists of the institution and was expected to be conducted without fail. Vancomycin was used as the index surrogate pharmacokinetically monitored medication within the module for testing and validation because of the clear expectations and standardized resources available to pharmacists to complete the task. The pharmacokinetics scoring module was designed specifically for the function of dosing management, searching throughout the EMR and concisely displaying the information a pharmacist needs to make a clinical decision. Importantly, integration of the scoring module reduced the time to intervention from hours to minutes. The median time to intervention was reduced to within a clinical working shift (8 hours) with the scoring module versus 24 hours or longer with the paper monitoring system. CONCLUSION: The implementation of an internally developed pharmacokinetics scoring module built into the EMR substantially reduced the time to clinical intervention for pharmacokinetic monitoring of vancomycin drug levels.

Modifications to a commercially available linear mass spectrometer for mass-resolved microscopy with the pixel imaging mass spectrometry (PImMS) camera.

RATIONALE: Imaging mass spectrometry is a powerful analytical technique capable of accessing a large volume of spatially resolved, chemical data from two-dimensional samples. Probing the entire surface of a sample simultaneously requires a detector with high spatial and temporal resolutions, and the ability to observe events relating to different mass-to-charge ratios. METHODS: A commercially available time-of-flight mass spectrometer, designed for matrix-assisted laser desorption/ionization (MALDI) analysis, was combined with the novel pixel imaging mass spectrometry (PImMS) camera in order to perform multi-mass, microscope-mode imaging experiments. A number of minor modifications were made to the spectrometer hardware and ion optics so that spatial imaging was achieved for a number of small molecules. RESULTS: It was shown that a peak width of Δm50 % < 1 m/z unit across the range 200 ≤ m/z ≤ 800 can be obtained while also achieving an optimum spatial resolution of 25 µm. It was further shown that these data were obtained simultaneously for all analytes present without the need to scan the experimental parameters. CONCLUSIONS: This work demonstrates the capability of multi-mass, microscope-mode imaging to reduce the acquisition time of spatially distributed analytes such as multi-arrays or biological tissue sections. It also shows that such an instrument can be commissioned by effecting relatively minor modifications to a conventional commercial machine.

The application of the fast, multi-hit, pixel imaging mass spectrometry sensor to spatial imaging mass spectrometry.

Imaging mass spectrometry is a powerful technique that allows chemical information to be correlated to a spatial coordinate on a sample. By using stigmatic ion microscopy, in conjunction with fast cameras, multiple ion masses can be imaged within a single experimental cycle. This means that fewer laser shots and acquisition cycles are required to obtain a full data set, and samples suffer less degradation as overall collection time is reduced. We present the first spatial imaging mass spectrometry results obtained with a new time-stamping detector, named the pixel imaging mass spectrometry (PImMS) sensor. The sensor is capable of storing multiple time stamps in each pixel for each time-of-flight cycle, which gives it multi-mass imaging capabilities within each pixel. A standard velocity-map ion imaging apparatus was modified to allow for microscope mode spatial imaging of a large sample area (approximately 5 × 5 mm(2)). A variety of samples were imaged using PImMS and a conventional camera to determine the specifications and possible applications of the spectrometer and the PImMS camera.

Drag enhancement of aqueous electrolyte solutions in turbulent pipe flow.

Detailed experimental results are presented for both laminar and turbulent flow of aqueous solutions in pipes of different diameters. Nonelectrolytes, such as sugar solutions followed the normal Moody pressure loss curves. Drag enhancement was demonstrated for turbulent flow of aqueous electrolyte solutions but not for laminar flow. The increased pressure drop for turbulent electrolyte flow was attributed to an electroviscous effect and a theory was developed to explain the drag enhancement. The increased pressure drop for the turbulent region of flow was shown to depend on the Debye length in the laminar sublayer on the pipe wall. Reasonable predictions of the increasing drag were obtained for both 1:1 and 2:1 electrolyte solutions.

Self-built supercritical CO2 anti-solvent unit design, construction and operation using carbamazepine.

The purpose of this study was to design and build a supercritical CO(2) anti-solvent (SAS) unit and use it to produce microparticles of the class II drug carbamazepine. The operation conditions of the constructed unit affected the carbamazepine yield. Optimal conditions were: organic solution flow rate of 0.15 mL/min, CO(2) flow rate of 7.5 mL/min, pressure of 4,200 psi, over 3,000 s and at 33 degrees C. The drug solid-state characteristics, morphology and size distribution were examined before and after processing using X-ray powder diffraction and differential scanning calorimetry, scanning electron microscopy and laser diffraction particle size analysis, respectively. The in vitro dissolution of the treated particles was investigated and compared to that of untreated particles. Results revealed a change in the crystalline structure of carbamazepine with different polymorphs co-existing under various operation conditions. Scanning electron micrographs showed a change in the crystalline habit from the prismatic into bundled whiskers, fibers and filaments. The volume weighted diameter was reduced from 209 to 29 mum. Furthermore, the SAS CO(2) process yielded particles with significantly improved in vitro dissolution. Further research is needed to optimize the operation conditions of the self-built unit to maximize the production yield and produce a uniform polymorphic form of carbamazepine.

Multidisciplinary strategies for the management of heart failure patients at high risk for admission: a systematic review of randomized trials.

OBJECTIVES: The aim of this study was to determine whether multidisciplinary strategies improve outcomes for heart failure (HF) patients. BACKGROUND: Because the prognosis of HF remains poor despite pharmacotherapy, there is increasing interest in alternative models of care delivery for these patients. METHODS: Randomized trials of multidisciplinary management programs in HF were identified by searching electronic databases and bibliographies and via contact with experts. RESULTS: Twenty-nine trials (5,039 patients) were identified but were not pooled, because of considerable heterogeneity. A priori, we divided the interventions into homogeneous groups that were suitable for pooling. Strategies that incorporated follow-up by a specialized multidisciplinary team (either in a clinic or a non-clinic setting) reduced mortality (risk ratio [RR] 0.75, 95% confidence interval [CI] 0.59 to 0.96), HF hospitalizations (RR 0.74, 95% CI 0.63 to 0.87), and all-cause hospitalizations (RR 0.81, 95% CI 0.71 to 0.92). Programs that focused on enhancing patient self-care activities reduced HF hospitalizations (RR 0.66, 95% CI 0.52 to 0.83) and all-cause hospitalizations (RR 0.73, 95% CI 0.57 to 0.93) but had no effect on mortality (RR 1.14, 95% CI 0.67 to 1.94). Strategies that employed telephone contact and advised patients to attend their primary care physician in the event of deterioration reduced HF hospitalizations (RR 0.75, 95% CI 0.57 to 0.99) but not mortality (RR 0.91, 95% CI 0.67 to 1.29) or all-cause hospitalizations (RR 0.98, 95% CI 0.80 to 1.20). In 15 of 18 trials that evaluated cost, multidisciplinary strategies were cost-saving. CONCLUSIONS: Multidisciplinary strategies for the management of patients with HF reduce HF hospitalizations. Those programs that involve specialized follow-up by a multidisciplinary team also reduce mortality and all-cause hospitalizations.

The current cost of heart failure to the National Health Service in the UK.

We have recently shown that heart failure admission rates continue to increase in the UK -- particularly in older age groups. As hospital activity represents the major cost component of health care expenditure related to heart failure, this study evaluated the current cost of this syndrome to the National Health Service (NHS) in the UK. We applied contemporary estimates of health care activity associated with heart failure to the whole UK population on an age and sex-specific basis to calculate its cost to the NHS for the year 1995. Direct components of health care included in these estimates were hospital admissions associated with a principal diagnosis of heart failure, associated outpatient consultations, general practice consultations and prescribed drug therapy. We also calculated the cost of nursing-home care following a primary heart failure admission and the cost of hospitalisations associated with a secondary diagnosis of heart failure. Adjusting for probable increases in hospital activity and the progressive ageing of the UK population, we have also projected the cost of heart failure to the NHS for the year 2000. We estimated that there were 988000 individuals requiring treatment for heart failure in the UK during 1995. The 'direct' cost of health care for these patients was estimated to be pound 716 million, or 1.83% of total NHS expenditure. Hospitalisations and drug prescriptions accounted for 69 and 18% of this expenditure, respectively. The additional costs associated with long-term nursing home care and secondary heart failure admissions accounted for a further pound 751 million (2.0% of total NHS expenditure). By the year 2000, we estimated that the combined total direct cost of heart failure would have risen to pound 905 million -- equivalent to 1.91% of total NHS expenditure. Using well-validated sets of data, these findings re-confirm the importance of heart failure as a major public health problem in the UK. The annual direct cost of heart failure to the NHS in 2000 is likely to be of the order of 1.9% of total expenditure -- the predominant cost component being hospitalisation.

An adhesion assay using minimal shear force to remove nonadherent cells.

A new 96-well microtiter plate based adhesion assay was developed to measure weak cell adhesion. This assay is distinct from other adhesion assays by the procedure in which the nonadherent cells are removed. In most conventional adhesion assays, nonadherent cells are removed by aspiration followed by repeated washes. However, the shear force generated by such washing also detaches weakly adherent cells. In the minimal shear force adhesion assay (MSFA) described here, the removal of nonadherent cells is carried out by applying a gentle shear force in a fluid environment. In this procedure, adherent cells are not subjected to harsh and variable washing forces and are not exposed to surface tension caused by the removal of washing fluid between successive washes. Using the lymphoid cell lines XC1.5/51 and MPC11, the number of adherent cells determined by this new adhesion assay is three times higher than the conventional adhesion assay. This MSFA assay is simple, consistent, and easy to perform. With modifications for applying a defined shear force, this assay can be adopted to compare cell adhesion strength to various substrata.