288 research outputs found
Can pervasive sensing address current challenges in global healthcare?
Important challenges facing global healthcare include the increase in the number of people affected by escalating healthcare costs, chronic and infectious diseases, the need for better and more affordable elderly care and expanding urbanisation combined with air and water pollution. Recent advances in pervasive sensing technologies have led to miniaturised sensor networks that can be worn or integrated within the living environment without affecting a person's daily patterns. These sensors promise to change healthcare from snapshot measurements of physiological parameters to continuous monitoring enabling clinicians to provide guidance on a daily basis. This article surveys several of the solutions provided by these sensor platforms from elderly care to neonatal monitoring and environmental mapping. Some of the opportunities available and the challenges facing the adoption of such technologies in large-scale epidemiological studies are also discussed
Weak Boundary Conditions for Lagrangian Shock Hydrodynamics: A High-Order Finite Element Implementation on Curved Boundaries
We propose a new Nitsche-type approach for weak enforcement of normal
velocity boundary conditions for a Lagrangian discretization of the
compressible shock-hydrodynamics equations using high-order finite elements on
curved boundaries. Specifically, the variational formulation is appropriately
modified to enforce free-slip wall boundary conditions, without perturbing the
structure of the function spaces used to represent the solution, with a
considerable simplification with respect to traditional approaches. Total
energy is conserved and the resulting mass matrices are constant in time. The
robustness and accuracy of the proposed method are validated with an extensive
set of tests involving nontrivial curved boundaries
Pulse oximetry optical sensor using oxygen-bound haemoglobin
In this paper we report a unique approach to measuring oxygen saturation levels by utilising the wavelength of the haemoglobin instead of the conventional absorption difference. Two experiments are set up to measure the wavelength of the haemoglobin bound to oxygen at different oxygen saturation levels with the help of a spectrometer. We report a unique low cost and robust wavelength monitoring SpO2 sensor that measures the SpO2 by using the colour of the blood and not the absorption difference of oxyhaemoglobin and deoxyhaemoglobin. With use of a spectrometer, we show that the wavelength of the oxygen-bound haemoglobin has a relation to the oxygen saturation level. The proposed device is designed and experimentally implemented with a colour sensor to measure the SpO2 level of the blood
Evidence for Two Modes of Synergistic Induction of Apoptosis by Mapatumumab and Oxaliplatin in Combination with Hyperthermia in Human Colon Cancer Cells
Colorectal cancer is the third leading cause of cancer-related mortality in the world-- the main cause of death from colorectal cancer is hepatic metastases, which can be treated with isolated hepatic perfusion (IHP). Searching for the most clinically relevant approaches for treating colorectal metastatic disease by isolated hepatic perfusion (IHP), we developed the application of oxaliplatin concomitantly with hyperthermia and humanized death receptor 4 (DR4) antibody mapatumumab (Mapa), and investigated the molecular mechanisms of this multimodality treatment in human colon cancer cell lines CX-1 and HCT116 as well as human colon cancer stem cells Tu-12, Tu-21 and Tu-22. We showed here, in this study, that the synergistic effect of the multimodality treatment-induced apoptosis was caspase dependent and activated death signaling via both the extrinsic apoptotic pathway and the intrinsic pathway. Death signaling was activated by c-Jun N-terminal kinase (JNK) signaling which led to Bcl-xL phosphorylation at serine 62, decreasing the anti-apoptotic activity of Bcl-xL, which contributed to the intrinsic pathway. The downregulation of cellular FLICE inhibitory protein long isoform (c-FLIPL) in the extrinsic pathway was accomplished through ubiquitination at lysine residue (K) 195 and protein synthesis inhibition. Overexpression of c-FLIPL mutant (K195R) and Bcl-xL mutant (S62A) completely abrogated the synergistic effect. The successful outcome of this study supports the application of multimodality strategy to patients with colorectal hepatic metastases who fail to respond to standard chemoradiotherapy that predominantly targets the mitochondrial apoptotic pathway. © 2013 Song et al
Improved Adaptive Group Testing Algorithms with Applications to Multiple Access Channels and Dead Sensor Diagnosis
We study group-testing algorithms for resolving broadcast conflicts on a
multiple access channel (MAC) and for identifying the dead sensors in a mobile
ad hoc wireless network. In group-testing algorithms, we are asked to identify
all the defective items in a set of items when we can test arbitrary subsets of
items. In the standard group-testing problem, the result of a test is
binary--the tested subset either contains defective items or not. In the more
generalized versions we study in this paper, the result of each test is
non-binary. For example, it may indicate whether the number of defective items
contained in the tested subset is zero, one, or at least two. We give adaptive
algorithms that are provably more efficient than previous group testing
algorithms. We also show how our algorithms can be applied to solve conflict
resolution on a MAC and dead sensor diagnosis. Dead sensor diagnosis poses an
interesting challenge compared to MAC resolution, because dead sensors are not
locally detectable, nor are they themselves active participants.Comment: Expanded version of a paper appearing in ACM Symposium on Parallelism
in Algorithms and Architectures (SPAA), and preliminary version of paper
appearing in Journal of Combinatorial Optimizatio
Computationally efficient 3D analytical magnet loss prediction in surface mounted permanent magnet machines
This study proposes a computationally efficient analytical method, for accurate prediction of three-dimensional (3D) eddy current loss in the rotor magnets of surface mounted permanent magnet (SPM) machines considering slotting effect. Subdomain model incorporating stator tooth tips is employed to generate the information on radial and tangential time-derivatives of 2D magnetic field (eddy current sources) within the magnet. The distribution of the eddy current sources in 3D is established for the magnets by applying the eddy current boundary conditions and the Coulomb gauge imposed on the current vector potential. The 3D eddy current distributions in magnets are derived analytically by employing the method of variable separation and the total eddy current loss in the magnets are subsequently established. The method is validated by 3D time-stepped finite element analysis for 18-slot, 8-pole and 12-slot, 8-pole permanent magnet machines. The eddy current loss variations in the rotor magnets with axial and circumferential number of segmentations are studied. The reduction of magnet eddy current loss is investigated with respect to harmonic wavelength of the source components to suggest a suitable segmentation for the rotor magnets in SPM machines
Transanal total mesorectal excision: a pure NOTES approach for selected patients
Background: The concept of natural orifice transluminal endoscopic surgery (NOTES) has stimulated the development of various “incisionless” procedures. One of the most popular is the transanal approach for rectal lesions. The aims of this study were to report how we standardized NOTES technique for transanal mesorectal excision without abdominal assistance, discuss the difficulties and surgical outcomes of this technique and report its feasibility in a small group of selected patients. Methods: Three consecutive female patients underwent transanal NOTES rectal resection without transabdominal laparoscopic assistance for rectal lesions. Functional results were assessed with the Fecal Incontinence Quality of Life scale and the Wexner score. Results: The technical steps are described in details and complemented with a video. All procedures were completed without transabdominal laparoscopic help. The mesorectal plane was entirely dissected without any disruption, and distal and circumferential margins were tumor-free. No major complications were observed. Functional results show a significant impairment after surgery with improvement at 6 months to levels near those of the preoperative period. Conclusions: The performance and publication of NOTES procedures are subject to much discussion. Despite the small number of patients, this procedure appears feasible and can be accomplished maintaining fecal continence and respecting oncologic principles
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