Estimating the Reach of a Manifold via its Convexity Defect Function.

The reach of a submanifold is a crucial regularity parameter for manifold learning and geometric inference from point clouds. This paper relates the reach of a submanifold to its convexity defect function. Using the stability properties of convexity defect functions, along with some new bounds and the recent submanifold estimator of Aamari and Levrard (Ann.

The Measurement of Food Insecurity in High-Income Countries: A Scoping Review.

The measurement of food insecurity is essential to monitor the prevalence, risk factors, consequences and effects of food insecurity and the interventions and policies implemented to tackle it. Yet, how best to apply it remains an unsettled issue due to the multifaceted and context-dependent nature of food insecurity. We report a scoping review of measures of food insecurity at the individual and household level in high-income countries with the final purpose of facilitating a catalogue of instruments to be used by both researchers and practitioners.

Principles of diagnostic sonography in iliopsoas tendon pathology: A case report.

This article describes the diagnostic value of musculoskeletal sonography in the management of tendon pathology and outlines a clinical example of its scope of utilization. Herein we describe the case of a 65-year-old man who sought rehabilitation services for left groin pain following a period of intense trekking and uphill walking. He presented with left hip flexor weakness and local tenderness over the left iliopsoas tendon with negative findings on neurological evaluation.

Capillary Rise of Nanostructured Microwicks.

Capillarity refers to the driving force to propel liquid through small gaps in the absence of external forces, and hence enhanced capillary force has been pursued for various applications. In this study, flower like ZnO nanostructures are successfully deposited to enhance capillarity of microwick structures that are specially designed to augment boiling heat transfer performance. Microreactor-assisted nanomaterial deposition, MAND, is employed with a flow cell to deposit the ZnO nanostructures on a large sized microwick (4.

Spanish adaptation and validation of the Child Food Security Survey Module (CFSSM-S).

Objective: The present study aimed to assess the: (i) internal structure of the Spanish Child Food Security Survey Module (CFSSM-S) with exploratory and confirmatory factor analysis (EFA and CFA); (ii) measurement invariance by gender, grade, weight status, socio-economic status (SES) and family affluence; and (iii) relationships with these external variables.

Design: A cross-sectional study was conducted. The CFSSM-S and other tools were employed to assess food insecurity, weight status, SES and family affluence, respectively.

Adhesive barnacle peptides exhibit a steric-driven design rule to enhance adhesion between asymmetric surfaces.

Barnacles exhibit superior underwater adhesion simply through sequencing of the 21 proteinogenic amino acids, without post processing or using special amino acids. Here, we measure and discuss the molecular interaction of two distinct and recurring short peptide sequences (Bp1 and Bp2) inspired from the surface binding 19kDa protein from the barnacle attachment interface. Using self-assembled monolayer (SAMs) of known physical and chemical properties on molecularly smooth gold substrates in 5mM NaCl at pH 7.

Academic program models for undergraduate biomedical engineering.

There is a proliferation of medical devices across the globe for the diagnosis and therapy of diseases. Biomedical engineering (BME) plays a significant role in healthcare and advancing medical technologies thus creating a substantial demand for biomedical engineers at undergraduate and graduate levels. There has been a surge in undergraduate programs due to increasing demands from the biomedical industries to cover many of their segments from bench to bedside.

Promoting interdisciplinary project-based learning to build the skill sets for research and development of medical devices in academia.

The worldwide need for rapid expansion and diversification of medical devices and the corresponding requirements in industry pose arduous challenges for educators to train undergraduate biomedical engineering (BME) students. Preparing BME students for working in the research and development (R&D) in medical device industry is not easily accomplished by adopting traditional pedagogical methods. Even with the inclusion of the design and development elements in capstone projects, medical device industry may be still experience a gap in fulfilling their needs in R&D.

Project-based learning with international collaboration for training biomedical engineers.

Training biomedical engineers while effectively keeping up with the fast paced scientific breakthroughs and the growth in technical innovations poses arduous challenges for educators. Traditional pedagogical methods are employed for coping with the increasing demands in biomedical engineering (BME) training and continuous improvements have been attempted with some success. Project-based learning (PBL) is an academic effort that challenges students by making them carry out interdisciplinary projects aimed at accomplishing a wide range of student learning outcomes.

Collaboration for cooperative work experience programs in biomedical engineering education.

Incorporating cooperative education modules as a segment of the undergraduate educational program is aimed to assist students in gaining real-life experience in the field of their choice. The cooperative work modules facilitate the students in exploring different realistic aspects of work processes in the field. The track records for cooperative learning modules are very positive.

Editorial comment on Malkin and Keane (2010).

Malkin and Keane (Med Biol Eng Comput, 2010) take an innovative approach to determine if unused, broken medical and laboratory equipment could be repaired by volunteers with limited resources. Their positive results led them to suggest that resource-poor countries might benefit from an on-the-job educational program for local high school graduates. The program would train biomedical technician assistants (BTAs) who would repair medical devices and instrumentation and return them to service.

Incorporating temporal information into level set functional for robust ventricular boundary detection from echocardiographic image sequence.

Echocardiographic images often suffer from dropouts that lead to loss of signals on the ventricular boundary and cause the level set curve used to detect the boundary leaking out from the gaps on the boundary. In this paper, a novel method that incorporates temporal information into the level set functional is proposed to solve the leakage problem encountered when detecting the heart wall boundary from the echocardiographic image sequence. The ventricular boundary is quantitatively partitioned and classified into strong and weak segments.

Incorporating temporal information into active contour method for detecting heart wall boundary from echocardiographic image sequence.

A new method which incorporates temporal information into the active contour function is proposed to solve the dropout and speckle noise problems encountered when detecting the inner heart wall boundary from echocardiographic image sequence. The ventricular boundary is considered to be composed of strong and weak segments. The weak segments are interfered by image degradations in ultrasound, and they are too weak to constrain the curve evolution.

Watershed-presegmented snake for boundary detection and tracking of left ventricle in echocardiographic images.

In this paper, an automated method of boundary detection of the left ventricle (LV) is proposed. The method uses a watershed transform and morphological operation to locate the region containing the LV, then performs snake deformation with a multiscale directional edge map for the detection of the endocardial boundary of the LV.

Characteristic wave detection in ECG signal using morphological transform.

Background: Detection of characteristic waves, such as QRS complex, P wave and T wave, is one of the essential tasks in the cardiovascular arrhythmia recognition from Electrocardiogram (ECG).

Methods: A multiscale morphological derivative (MMD) transform-based singularity detector, is developed for the detection of fiducial points in ECG signal, where these points are related to the characteristic waves such as the QRS complex, P wave and T wave. The MMD detector is constructed by substituting the conventional derivative with a multiscale morphological derivative.

Life-threatening ventricular arrhythmia recognition by nonlinear descriptor.

Background: Ventricular tachycardia (VT) and ventricular fibrillation (VF) are ventricular cardiac arrhythmia that could be catastrophic and life threatening. Correct and timely detection of VT or VF can save lives.

Methods: In this paper, a multiscale-based non-linear descriptor, the Hurst index, is proposed to characterize the ECG episode, so that VT and VF can be recognized as different from normal sinus rhythm (NSR) in the descriptor domain.

VLOD: high-fidelity walkthrough of large virtual environments.

We present visibility computation and data organization algorithms that enable high-fidelity walkthroughs of large 3D geometric data sets. A novel feature of our walkthrough system is that it performs work proportional only to the required detail in visible geometry at the rendering time. To accomplish this, we use a precomputation phase that efficiently generates per cell vLOD: the geometry visible from a view-region at the right level of detail.

Feature extraction for the analysis of colon status from the endoscopic images.

Background: Extracting features from the colonoscopic images is essential for getting the features, which characterizes the properties of the colon. The features are employed in the computer-assisted diagnosis of colonoscopic images to assist the physician in detecting the colon status.

Methods: Endoscopic images contain rich texture and color information.

Spectral polarization measurements by use of the grating division-of-amplitude photopolarimeter.

The grating division-of-amplitude photopolarimeter (G-DOAP) is an instrument that exploits the multiple-beam-splitting, polarizing, and dispersive properties of diffraction gratings for the time-resolved measurement of the complete state of polarization of collimated broadband incident light, as represented by the four Stokes parameters as a function of wavelength across the spectrum. It is a compact, high-speed sensor that has no moving parts and is simple to install and operate. These characteristics make the G-DOAP well suited for in situ spectroscopic ellipsometry (SE) applications for monitoring and controlling thin-film processes.

Cardiac arrhythmia classification using autoregressive modeling.

Background: Computer-assisted arrhythmia recognition is critical for the management of cardiac disorders. Various techniques have been utilized to classify arrhythmias. Generally, these techniques classify two or three arrhythmias or have significantly large processing times.

ECG signal conditioning by morphological filtering.

Clinically obtained electrocardiographic (ECG) signals are often contaminated with different types of noise and baseline drifting commonly occurs. In order to facilitate automated ECG analysis, signal conditioning is undoubtedly a necessity. In this paper, a modified morphological filtering (MMF) technique is used for signal conditioning in order to accomplish baseline correction and noise suppression with minimum signal distortion.

Detection and measurement of retinal vessels in fundus images using amplitude modified second-order Gaussian filter.

In this paper, the fitness of estimating vessel profiles with Gaussian function is evaluated and an amplitude-modified second-order Gaussian filter is proposed for the detection and measurement of vessels. Mathematical analysis is given and supported by a simulation and experiments to demonstrate that the vessel width can be measured in linear relationship with the "spreading factor" of the matched filter when the magnitude coefficient of the filter is suitably assigned. The absolute value of vessel diameter can be determined simply by using a precalibrated line, which is typically required since images are always system dependent.