Bare-handed 3D drawing in augmented reality

Head-mounted augmented reality (AR) enables embodied in situ drawing in three dimensions (3D).We explore 3D drawing interactions based on uninstrumented, unencumbered (bare) hands that preserve the user’s ability to freely navigate and interact with the physical environment. We derive three alternative interaction techniques supporting bare-handed drawing in AR from the literature and by analysing several envisaged use cases. The three interaction techniques are evaluated in a controlled user study examining three distinct drawing tasks: planar drawing, path description, and 3D object reconstruction. The results indicate that continuous freehand drawing supports faster line creation than the control point-based alternatives, although with reduced accuracy. User preferences for the different techniques are mixed and vary considerably between the different tasks, highlighting the value of diverse and flexible interactions. The combined effectiveness of these three drawing techniques is illustrated in an example application of 3D AR drawing

Intoxicación de equinos por Senecio pp en el noroeste argentino

La toxicidad de varias especies del género Senecio es bien conocida a nivel mundial. En Argentina se han descrito casos en bovinos pero los registros son escasos. En este trabajo se describen cuadros de seneciosis equina en dos predios rurales del noroeste argentino (Salta). Se mencionan los hallazgos clínicos y patológicos, caracterizados por fibrosis hepática, megalocitosis, hiperplasia biliar y colestasis. En individuos afectados se observó pérdida de peso, depresión, ataxia y dificultad para deambular. En las áreas de pastoreo se identificó la presencia de Senecio rudbeckiaefolius, S. madagascariensis y S. hieronymi. Se identificaron y cuantificaron alcaloides pirrolizidínicos en estas tres especies, mediante cromatografía gaseosa acoplada a espectrometría de masa. Se determinó la presencia de senecionina, integerrimina, usaramina, jacozina, jacobina, senecivernina, platyphyllina y neoplatyphyllina. Los resultados obtenidos confirman la intoxicación de equinos por Senecio en Argentina y ponen de manifiesto los primeros hallazgos de alcaloides pirrolizidínicos en tres especies de Senecio endémicas para el noroeste del país

Role of lipid apheresis in changing times

During the last decades, LDL-apheresis was established as an extracorporeal treatment option for patients with severe heterozygous or homozygous familial hypercholesterolemia (FH) that is resistant to conventional treatment strategies such as diet, drugs, and changes in lifestyle. Nearly half a century ago, the first LDL-apheresis treatment was performed by plasma exchange in a child with homozygous FH

Lipid apheresis techniques: current status in Germany

For long-term lipid apheresis therapy, several different technical systems have been developed which enable effective reduction of LDL cholesterol and other atherogenic lipoproteins, such as Lp(a), with sufficient selectivity and good clinical tolerance. Suitable techniques include whole blood adsorption with polyacrylamide and dextran sulfate cellulose, while primary plasma separation is used for cascade filtration, heparin-induced precipitation, immunoadsorption, silicate gel adsorption, and dextran sulfate cellulose (both techniques)

Joint Assessment of Structural, Perfusion, and Diffusion MRI in Alzheimer's Disease and Frontotemporal Dementia

Most MRI studies of Alzheimer's disease (AD) and frontotemporal dementia (FTD) have assessed structural, perfusion and diffusion abnormalities separately while ignoring the relationships across imaging modalities. This paper aimed to assess brain gray (GM) and white matter (WM) abnormalities jointly to elucidate differences in abnormal MRI patterns between the diseases. Twenty AD, 20 FTD patients, and 21 healthy control subjects were imaged using a 4 Tesla MRI. GM loss and GM hypoperfusion were measured using high-resolution T1 and arterial spin labeling MRI (ASL-MRI). WM degradation was measured with diffusion tensor imaging (DTI). Using a new analytical approach, the study found greater WM degenerations in FTD than AD at mild abnormality levels. Furthermore, the GM loss and WM degeneration exceeded the reduced perfusion in FTD whereas, in AD, structural and functional damages were similar. Joint assessments of multimodal MRI have potential value to provide new imaging markers for improved differential diagnoses between FTD and AD

A novel approach to modeling tissue-level activity of cortisol levels according to the theory of Endobiogeny, applied to chronic heart failure

Background: Chronic heart failure (CHF) is an inflammatory disorder in which cortisol plays an important role. Despite this, cortisol is not routinely quantitatively measured for a number of reasons. It is considered non-specific. Accuracy and validity remain in question. It is not considered convenient or cost effective. Finally, tissue level effects of cortisol do not correlate linearly to quantitative levels. If the functional, tissue level effectiveness of cortisol could be modeled, its evaluation in CHF patient may become relevant. Endobiogeny is a global systems theory that claims to be able to model complex physiology through biomarkers, offering context-rich interpretations of data for meaningful clinical applicability. Cortisol is known to alter circulating levels of elements from a complete blood count (CBC). By relating these biomarkers in a qualitative fashion, the theory of Endobiogeny posits that these elements can be contextualized to reflect the tissue level activity of cortisol, referred to as the cortisol index (CI). The algorithm derived from the theory is called the Biology of Functions (BoF). Aim: The aim of this study was to determine if the cortisol index is accurate in reflecting a greater expression of cortisol activity in ambulatory CHF patients versus controls subjects. Methods: A retrospective observational case control study was performed in 93 patients with New York Heart Association class II-III heart failure patients and 104 individuals with no cardiovascular pathology as a control group. Results from a CBC were entered into BOF modeling software, from which the cortisol index is derived. Results: The Cortisol index (3-7) was significantly elevated in CHF vs. control patients (12.8±0.91 vs. 8.48±0.74, p< 001), as were individual CBC elements used to form the index. Conclusions: The cortisol index, derived from the theory of Endobiogeny showed results consistent with CHF pathophysiology. The cortisol index was able to model the effective tissue level activity of cortisol in CHF patients using only a CBC, without measuring serum cortisol. Future studies should compare the cortisol index to standard inflammatory markers in CHF patients to further correlate the validity of the index to other known effects of cortisol

Therapeutic apheresis in peripheral and retinal circulatory disorders

In microcirculation disorders, the therapeutic apheresis seems to have two different effects. The first, achieved after only a few sessions, is acute, consisting of drastic reduction of blood viscosity and obtained with the use of low-density lipoprotein (LDL) apheresis, rheopheresis, or fibrinogen apheresis. The second effect is long term, or chronic, and needs to be evaluated after a long course of treatment. The mechanisms underlying the chronic effect are still objects of debate and take into account the pleiotropic effects of apheresis. However, it is likely that the acute effect of apheresis mainly influences the functional components of the vascular damage, and so the derived rheological benefit might last only for a short period. The chronic effect, on the contrary, by acting on the morphological alterations of the vascular walls, requires the apheresis treatment to be prolonged for a longer period or even cycles of treatment to be programmed

Accrual and Recruitment Practices at Clinical and Translational Science Award (CTSA) Institutions: A Call for Expectations, Expertise, and Evaluation

To respond to increased public and programmatic demand to address underenrollment of clinical translational research studies, the authors examine participant recruitment practices at Clinical and Translational Science Award sites (CTSAs) and make recommendations for performance metrics and accountability

Perfusion by Arterial Spin Labelling following Single Dose Tadalafil in Small Vessel Disease (PASTIS): study protocol for a randomized controlled trial

Background Cerebral small vessel disease is a common cause of vascular cognitive impairment in older people, with no licensed treatment. Cerebral blood flow is reduced in small vessel disease. Tadalafil is a widely prescribed phosphodiesterase-5 inhibitor that increases blood flow in other vascular territories. The aim of this trial is to test the hypothesis that tadalafil increases cerebral blood flow in older people with small vessel disease. Methods/design Perfusion by Arterial Spin labelling following Single dose Tadalafil In Small vessel disease (PASTIS) is a phase II randomised double-blind crossover trial. In two visits, 7-30 days apart, participants undergo arterial spin labelling to measure cerebral blood flow and a battery of cognitive tests, pre- and post-dosing with oral tadalafil (20 mg) or placebo. Sample size: 54 participants are required to detect a 15% increase in cerebral blood flow in subcortical white matter (p < 0.05, 90% power). Primary outcomes are cerebral blood flow in subcortical white matter and deep grey nuclei. Secondary outcomes are cortical grey matter cerebral blood flow and performance on cognitive tests (reaction time, information processing speed, digit span forwards and backwards, semantic fluency). Discussion Recruitment started on 4th September 2015 and 36 participants have completed to date (19th April 2017). No serious adverse events have occurred. All participants have been recruited from one centre, St George’s University Hospitals NHS Foundation Trust. Trial registration European Union Clinical Trials Register: EudraCT number 2015-001235-20. Registered on 13 May 2015