PPAP: Perspective Projection Augment Platform with Pan–Tilt Actuation for Improved Spatial Perception

In this paper, we propose PPAP, an augmented reality platform with an actuated projector for dynamic user-perspective projection. In PPAP, a stationary camera is used jointly with a pan–tilt motorized projector-camera unit. With the servo control of the steerable pan–tilt system, the system is able to continuously orient itself to match the user’s view center of the projection-mapped surface. This provides users with greatly widened viewing angles in the augmented scene, when compared to the stationary projection. Through user studies, in which users judged the size and distance of a projected virtual object, we verified that the perspective projection with the actuated projector helps users better understand the spatial relationship of the virtual object in the augmented scene in terms of depth perception

Nano-Interstice Driven Powerless Blood Plasma Extraction in a Membrane Filter Integrated Microfluidic Device

Blood plasma is a source of biomarkers in blood and a simple, fast, and easy extraction method is highly required for point-of-care testing (POCT) applications. This paper proposes a membrane filter integrated microfluidic device to extract blood plasma from whole blood, without any external instrumentation. A commercially available membrane filter was integrated with a newly designed dual-cover microfluidic device to avoid leakage of the extracted plasma and remaining blood cells. Nano-interstices installed on both sides of the microfluidic channels actively draw the extracted plasma from the membrane. The developed device successfully supplied 20 μL of extracted plasma with a high extraction yield (~45%) in 16 min

Extracting information from free-text electronic patient records to identify practice-based evidence of the performance of coronary stents

<div><p>Background and objective</p><p>Percutaneous coronary intervention (PCI) using drug-eluting stents (DES) is an indispensable treatment for coronary artery disease. However, to evaluate the performance of various types of stents for PCI, numerous resources are required. We extracted clinical information from free-text records and, using practice-based evidence, compared the efficacy of various DES.</p><p>Materials and methods</p><p>We developed a text mining tool based on regular expression and applied it to PCI reports stored in the electronic health records (EHRs) of Ajou University Hospital from 2010–2014. The PCI data were extracted from EHRs with a sensitivity of 0.996, a specificity of 1.000, and an F-measure of 0.995 when compared with a sample of 200 reports. Using these data, we compared the performance of stents by Kaplan-Meier analysis and the Cox hazard proportional regression.</p><p>Results</p><p>In the self-validation analysis comparing the first-generation to the second-generation DES, the second-generation DES was superior to the first-generation DES (hazard ratio [HR]: 0.423, 95% confidence interval [CI]: 0.284–0.630) in terms of target vessel revascularization (TVR), showing similar findings to the established results of previous studies. Among the second-generation DES, the biodegradable-polymer DES tended to be superior, with a risk of TVR (HR: 0.568, 95% CI: 0.281–1.147) falling below than that for the durable-polymer DES approximately 1 year after the index procedure. The Endeavor stent had the highest TVR risk among the newer generation DES (HR: 2.576, 95% CI: 1.273–5.210).</p><p>Conclusions</p><p>In this study, we demonstrated how to construct a PCI data warehouse of PCI-related parameters obtained from free-text electronic records with high accuracy for use in the post surveillance of coronary stents in a time- and cost effective manner. Post surveillance of the practice based evidence in the PCI data warehouse indicated that the biodegradable-polymer DES might have a lower risk of TVR than the durable-polymer DES.</p></div

Secondary Metabolites from Vietnamese Marine Invertebrates with Activity against Trypanosoma brucei and T. cruzi

Marine-derived natural products from invertebrates comprise an extremely diverse and promising source of the compounds from a wide variety of structural classes. This study describes the discovery of five marine natural products with activity against Trypanosoma species by natural product library screening using whole cell in vitro assays. We investigated the anti-trypanosomal activity of the extracts from the soft corals and echinoderms living in Vietnamese seas. Of the samples screened, the methanolic extracts of several marine organisms exhibited potent activities against cultures of Trypanosoma brucei and T. cruzi (EC50 &lt; 5.0 μg/mL). Among the compounds isolated from these extracts, laevigatol B (1) from Lobophytum crassum and L. laevigatum, (24S)-ergost-4-ene-3-one (2) from Sinularia dissecta, astropectenol A (3) from Astropecten polyacanthus, and cholest-8-ene-3β,5α,6β,7α-tetraol (4) from Diadema savignyi showed inhibitory activity against T. brucei with EC50 values ranging from 1.57 ± 0.14 to 14.6 ± 1.36 μM, relative to the positive control, pentamidine (EC50 = 0.015 ± 0.003 μM). Laevigatol B (1) and 5α-cholest-8(14)-ene-3β,7α-diol (5) exhibited also significant inhibitory effects on T. cruzi. The cytotoxic activity of the pure compounds on mammalian cells was also assessed and found to be insignificant in all cases. This is the first report on the inhibitory effects of marine organisms collected in Vietnamese seas against Trypanosoma species responsible for neglected tropical diseases

Comparison of target vessel revascularization free survival between the first- and second-generation stents.

<p>Comparison of target vessel revascularization free survival between the first- and second-generation stents.</p

Machine learning application for classification of Alzheimer's disease stages using 18F-flortaucipir positron emission tomography

Abstract Background The progression of Alzheimer’s dementia (AD) can be classified into three stages: cognitive unimpairment (CU), mild cognitive impairment (MCI), and AD. The purpose of this study was to implement a machine learning (ML) framework for AD stage classification using the standard uptake value ratio (SUVR) extracted from 18F-flortaucipir positron emission tomography (PET) images. We demonstrate the utility of tau SUVR for AD stage classification. We used clinical variables (age, sex, education, mini-mental state examination scores) and SUVR extracted from PET images scanned at baseline. Four types of ML frameworks, such as logistic regression, support vector machine (SVM), extreme gradient boosting, and multilayer perceptron (MLP), were used and explained by Shapley Additive Explanations (SHAP) to classify the AD stage. Results Of a total of 199 participants, 74, 69, and 56 patients were in the CU, MCI, and AD groups, respectively; their mean age was 71.5 years, and 106 (53.3%) were men. In the classification between CU and AD, the effect of clinical and tau SUVR was high in all classification tasks and all models had a mean area under the receiver operating characteristic curve (AUC) > 0.96. In the classification between MCI and AD, the independent effect of tau SUVR in SVM had an AUC of 0.88 (p < 0.05), which was the highest compared to other models. In the classification between MCI and CU, the AUC of each classification model was higher with tau SUVR variables than with clinical variables independently, which yielded an AUC of 0.75(p < 0.05) in MLP, which was the highest. As an explanation by SHAP for the classification between MCI and CU, and AD and CU, the amygdala and entorhinal cortex greatly affected the classification results. In the classification between MCI and AD, the para-hippocampal and temporal cortex affected model performance. Especially entorhinal cortex and amygdala showed a higher effect on model performance than all clinical variables in the classification between MCI and CU. Conclusions The independent effect of tau deposition indicates that it is an effective biomarker in classifying CU and MCI into clinical stages using MLP. It is also very effective in classifying AD stages using SVM with clinical information that can be easily obtained at clinical screening