A Smart Walker for People with Both Visual and Mobility Impairment

In recent years, significant work has been done in technological enhancements for mobility aids (smart walkers). However, most of this work does not cover the millions of people who have both mobility and visual impairments. In this paper, we design and study four different configurations of smart walkers that are specifically targeted to the needs of this population. We investigated different sensing technologies (ultrasound-based, infrared depth cameras and RGB cameras with advanced computer vision processing), software configurations, and user interface modalities (haptic and audio signal based). Our experiments show that there are several engineering choices that can be used in the design of such assistive devices. Furthermore, we found that a holistic evaluation of the end-to-end performance of the systems is necessary, as the quality of the user interface often has a larger impact on the overall performance than increases in the sensing accuracy beyond a certain point.

Value of Information Based Data Retrieval in UWSNs

Sensor nodes in underwater sensor networks may acquire data at a higher rate than their ability to communicate over underwater acoustic channels. Autonomous underwater vehicles may mitigate this mismatch by offloading high volumes of data from the sensor nodes and ferrying them to the sink. Such a mode of data transfer results in high latency. Occasionally, these networks need to report high priority events such as catastrophes or intrusions. In such a scenario the expectation is to have a minimal end-to-end delay for event reporting. Considering this, underwater vehicles should schedule their visits to the sensor nodes in a manner that aids efficient reporting of high-priority events. We propose the use of the Value of Information metric in order to improve the reporting of events in an underwater sensor network. The proposed approach classifies the recorded data in terms of its value and priority. The classified data is transmitted using a combination of acoustic and optical channels. We perform experiments with a binary event model, i.e., we classify the events into high-priority and low-priority events. We explore a couple of different path planning strategies for the autonomous underwater vehicle. Our results show that scheduling visits to sensor nodes, based on algorithms that address the value of information, improves the timely reporting of high priority data and enables the accumulation of larger value of information.

A theorem proving approach for automatically synthesizing visualizations of flow cytometry data

Background

Polychromatic flow cytometry is a popular technique that has wide usage in the medical sciences, especially for studying phenotypic properties of cells. The high-dimensionality of data generated by flow cytometry usually makes it difficult to visualize. The naive solution of simply plotting two-dimensional graphs for every combination of observables becomes impractical as the number of dimensions increases. A natural solution is to project the data from the original high dimensional space to a lower dimensional space while approximately preserving the overall relationship between the data points. The expert can then easily visualize and analyze this low-dimensional embedding of the original dataset.

Results

This paper describes a new method, SANJAY, for visualizing high-dimensional flow cytometry datasets. This technique uses a decision procedure to automatically synthesize two-dimensional and three-dimensional projections of the original high-dimensional data while trying to minimize distortion. We compare SANJAY to the popular multidimensional scaling (MDS) approach for visualization of small data sets drawn from a representative set of benchmarks, and our experiments show that SANJAY produces distortions that are 1.44 to 4.15 times smaller than those caused due to MDS. Our experimental results show that SANJAY also outperforms the Random Projections technique in terms of the distortions in the projections.

Conclusions

We describe a new algorithmic technique that uses a symbolic decision procedure to automatically synthesize low-dimensional projections of flow cytometry data that typically have a high number of dimensions. Our algorithm is the first application, to our knowledge, of using automated theorem proving for automatically generating highly-accurate, low-dimensional visualizations of high-dimensional data.

Non-Diabetic renal disease in Diabetes Mellitus: clinical features and renal biopsy findings

AIM

Renal diseases in diabetes mellitus (DM) patients, include diabetic nephropathies (DN) and non-diabetic renal diseases (NDRD). The clinical differentiation among them is usually not so clear and effective. Aim of this study which examined renal biopsies in patients with type-2 DM was to identify the prevalence and the nature of NDRD.

MATERIALS AND METHODS

We recorded the clinical and laboratory finding alongside with the histopathological examination of the renal biopsies obtained from 71 type-2 DM patients who underwent renal biopsy in our center. Based on the renal biopsy findings patients were classified into two groups (DN and NDRD) and data was compared between the two groups.

RESULTS

There were 42 women and 29 men; aged 55 ± 12 years. In patients with DN (n: 34), diabetic retinopathy was more common [16 (47.1 %) vs. 6 (16.2 %) respectively, p =0.01], duration of DM was longer (108.8 ± 58.8 months vs 57.8 ± 55.9 months respectively, p <0.001) and the degree of proteinuria was more severe (6 ± 4.3 g/day vs. 4.5 ± 4.6 g/day respectively, p =0.04) compared to the patients with NDRD. Regression analysis revealed that diabetes duration >60 months, presence of diabetic retinopathy and proteinuria >3.5 g/day were independent predictors of DN with 79.4 % sensitivity and 86.5% specificity. Focal segmental glomerulosclerosis was the most frequent diagnosis in patients with NDRD.

CONCLUSIONS

The prevalence of NDRD is remarkably frequent in DM patients in whom nephrologists consider renal biopsy an appropriate measure. Short duration of DM, degree of proteinuria and absence of retinopathy were predictors of NDRD. Hippokratia 2015; 19 (2):148-152.

Evaluation of heart rate recovery in patients with primary nephrotic syndrome

BACKGROUND/AIM

Abnormal heart rate recovery after an exercise stress test is a strong predictor of cardiovascular death in healthy subjects and various patient groups. The aim of the present study was to investigate heart rate recovery (HRR), a cardiovascular risk factor, in patients with primary nephrotic syndrome (NS).

MATERIAL AND METHODS

Forty patients with primary NS (mean age 39.6 ± 9.3 years) and 42 healthy subjects (mean age 36.0 ± 7.9) were included in the study. HRR was calculated by subtracting the heart rates in the first, second, and third minutes of the recovery period from the maximum heart rate, reached during the exercise stress test.

RESULTS

The HRR in the first minute was significantly slower in the NS group compared with the control group (25.5 ± 10.1 and 32.4 ± 11.1, respectively; p =0.004). The HRR in the second and third minutes was also slower in the NS group, but the difference was not statistically significant. When a comparative analysis of HRR and the etiology of NS was carried out, no difference was found at any time point.

CONCLUSIONS

Impaired first minute HRR was identified in patients with NS. This suggests that primary NS patients should be monitored due to the potential increased risk of cardiovascular disease. Hippokratia 2015; 19 (2):109-113.

Zoledronic acid and atrial fibrillation in cancer patients with bone metastases

e20591

Background: Treatment with a bisphosphonate was linked with a significantly increased risk for atrial fibrillation (AF) in a few studies. Once-yearly infusions of intravenous zoledronic acid (ZA) was also significantly increased serious AF in postmenopausal women with osteoporosis. This study was conducted to determine the frequency of atrial fibrillation among cancer patients receiving the standard treatment of ZA. Methods: One hundred and twenty-four cancer patients who had bone metastasis receiving ZA were included in this study. All patients have been receiving 4 mg ZA at 4-week intervals; with each dose administered over 15 minutes. Patients who presented outpatient clinic for any reason (routine control, chemotherapy, ZA administration) a short survey completed and standard 12-lead ECG recordings were obtained. Results: One hundred and twenty-four cancer patients with documented bone metastases were evaluated. Mean age of the patients was 55 ± 13.0 years, 60% of the patients were female. Forty-one percent of the patients had breast cancer and 17% non-small cell lung cancer and the remainder had other solid tumors. Mean duration of ZA administration was 13.4 ± 15.0 months/patients. Mean total cumulative dose was 54 ± 15.0 mg per patients. 60 (48%) of the patients were treated with antracycline including regimens, and 37 (30%) were treated with mediastinal radiotherapy that might effect the heart. Twenty-three percent of the patients had hypertension, 10% diabetes mellitus, 7% currently smoker and 32% exsmoker, 3.7% myocardial infarction history, 1.9% congestive heart failure, and 1% valvular disease. On ECG evaluation; we observed sinus rhythm in 58%, sinus tachycardia in 15%, sinus bradicardia in 3.2%, ventricular exracystole in 5.7% of the patients. There were no AF. Conclusions: Although most of the patients were also having potentially cardiotoxic treatment, there was no increase in AF frequency in cancer patients who were treated with intravenous ZA. We believe that the risk of AF is small and may increase with age and comorbidity.

No significant financial relationships to disclose.

Evaluation of the computer-based training module for the Marine medic

This is a follow-up article (found in JBC Vol. 25, No. 4, 1998) discussing the evaluation of the Computer-based Training Module (CBT) presented to the trainers of the medical first responders of the health care division of the Marine medics at Camp Pendelton, California. Their specific comments are embodied in the text of the article. The suggestions provided were to expand the existing CBT Module to include enhanced features.

How a computer-based training module for the marine medic was developed

This article is a discussion of how a prototype Computer-based Training (CBT) program module was developed by a team of people representing different nationalities and from various professions including nursing, engineering, and medical graphics. Multimedia solutions that would facilitate the training of Marine corpsmen to perform their mission as first responder in combat incidents were examined. Three separate software models were evaluated. The prototype chosen was selected because of its simplicity, user-friendliness, and cost effectiveness.