50 research outputs found
Synthesis, structure, spectroscopic properties and cytotoxic effect of some thiosemicarbazone complexes of palladium
No full textMicrofluidic particle tracking technique towards white blood cell subtype counting and serum protein quantification
No full textMicrofluidic technologies have gained wide acceptance in the past decade as diagnostics tools in clinical setting world-wide. This is primarily due to the fact that microfluidic technologies enable rapid, quantitative assays from small amount of physiological sample in an easy-to-use, portable platform. In this work, we will describe a microfluidic technique that can be built upon to count white blood cell subtypes or serum protein from a drop of blood. Traditionally, researchers have counted white blood cell subtypes by capturing them. However, an elegant and more accurate way to do the same is by exploiting the transitory interactions between the antigen on the surface of the cell and a cognate antibody. Cells expressing the antigen of interest will take longer to traverse a microchannel which has been coated with a cognate antibody compared to the cells which don't express that antigen. To our knowledge, no microfluidic assay exists which can rapidly count cells using this principle. Towards this end, we have developed a repeatable experimental technique to control the transit time and the order of particles in a microchannel. To least affect the uniformity of transit time, we have also optimized the geometry of pillars in the microchannel on which antibodies are functionalized.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2018-08-01The student, Tanmay Ghonge, accepted the attached license on 2016-07-20 at 20:20.The student, Tanmay Ghonge, submitted this Thesis for approval on 2016-07-20 at 20:22.This Thesis was approved for publication on 2016-07-22 at 15:07.DSpace SAF Submission Ingestion Package generated from Vireo submission #10043 on 2016-11-10 at 12:21:02Made available in DSpace on 2016-11-10T18:27:09Z (GMT). No. of bitstreams: 2
GHONGE-THESIS-2016.pdf: 2007682 bytes, checksum: 2e84b6da47c9ce69ad66e0b45f92a31f (MD5)
LICENSE.txt: 4210 bytes, checksum: 80de1a9885d9f902620d9b6cd84a0e36 (MD5)
Previous issue date: 2016-07-22Embargo set by: Seth Robbins for item 95295
Lift date: 2018-11-10T18:28:02Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 95295 on 2018-11-11T10:15:11Z
Peak Trekking of Hierarchy Mountain for the Detection of Cerebral Aneurysm using Modified Hough Circle Transform
No full textThe Circle of Willis is in the junction of two carotid arteries and two vertebral arteries that supply the brain with nutrition. Junctions where these arteries come together may develop weak spots that can balloon out and fill with blood, creating aneurysms. These sac-like areas may leak or rupture, spilling blood into surrounding tissues which may cause artery spasm leading to potential stroke or even death. Clipping and coiling are two treatment options preferred by neurosurgeon which require proper detection of aneurysm. Medical practitioners are therefore emphasizing on the prior detection of cerebral aneurysm (CA) before rupture occurs leading to subarachnoid haemorrhage (SAH). This paper presents a novel method by application of Modified Hough Circle Transform & Peak Trekking (MHCT-PT) technique on the image extracted from Digital subtraction angiography (DSA). Experimental results have firmly substantiated that the proposed method is highly efficient in properly detecting the location, size and type of aneurysm
A case report of mucoepidermoid carcinoma of the lung in an adolescent
No full textMucoepidermoid carcinoma of the lung (MEC) is a tumor of low-malignant potential of bronchial gland origin. Low-grade MEC has a better prognosis than high-grade tumor, the later being similar to that of nonsmall cell lung carcinoma. We report a case of 14-year-old girl who presented with cough along with expectoration and dyspnea. Imaging studies revealed a mass involving the right upper lobe bronchus. Surgical resection was done and pathological examination revealed an intermediate-grade MEC with tumor-free margins. No adjuvant treatment was considered. The patient had no signs of tumor recurrence with 1-year follow-up
Point-of-care microfluidic assays for measuring expression level of antigen on blood cells
No full textElevated expression of a membrane protein CD64 on neutrophils is linked with the onset of sepsis, a life-threatening syndrome that contributes to millions of deaths annually worldwide. The survival rate of septic patients falls rapidly every hour the appropriate medication is delayed. Therefore, automated and periodic measurements of CD64 expression (nCD64) at the patient’s bedside could lead to timely medical intervention, thereby saving lives and billions of dollars. Gold standard assays for measuring nCD64, such as flow cytometry, require manual sample preparation and long incubation times. For point-of-care applications, however, an assay should be able to measure nCD64 with little to no sample preparation.
This dissertation addresses the need by investigating portable, point-of-care platforms for measuring nCD64 from whole blood without any off-chip sample preparation. Our first platform is an electrical biosensor that measures nCD64 by measuring the fraction of immunologically captured cells expressing CD64. It consists of a capture chamber, for immunologically capturing cells and microfluidic coulter counters at its entrance and exit. In our study, we found that the fraction of cells expressing CD64 correlates linearly with nCD64. For our study, we optimized the geometry of the capture chamber and the coulter counters from the first principles of fluid mechanics and electrostatics respectively. This biosensor can produce a readout of nCD64 starting from just 10 μL of blood in 10 mins. Although this technique does not require off-chip sample preparation, red blood cells have to be lysed on-chip so that white blood cells can be counted by the electrical counters.
Lysing red blood cells on-chip adds a step which requires multiple pumps running in parallel. Ideally, the technique should be able to measure nCD64 without red blood cell lysis. Towards that, we have developed an optical, microfluidic cell capture assay that works from whole blood. We demonstrate the proof-of-concept of this assay by measuring the density of biotin molecules on beads. We injected beads in a capture chamber that is functionalized with neutravidin. Beads that have a higher density of travel, on average, shorter distances in the chamber before they get captured compared to the beads with a lower density of biotin. We developed a statistical model to extract the probability of capture (ε) per interaction with a pillar from the spatial distribution of beads in the channel. ε is found to be linearly proportional to the surface density of biotin.
We expanded this optical technique to measure the nCD64 on neutrophils. One μL blood whole blood is injected in a microfluidic channel consisting of a capture chamber functionalized with anti-CD64 antibodies. As was the case with beads, the immunologically captured have a distinct spatial signature of capture depending on the CD64 expression level. Samples with higher CD64 expression travel, on average, a shorter distance in the channel. Using the same statistical model used to quantify biotin density on beads, we quantified CD64 expression on neutrophils. To make this technique easily translatable to a point-of-care device, we assembled a smartphone-imaging set-up to replace bulky microscopes. Our smartphone microscope can measure CD64 from whole blood without the need for any sample preparation in about 20 mins. We believe that deploying this technology in hospitals could save millions of lives worldwide.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2021-05-01The student, Tanmay Ghonge, accepted the attached license on 2019-02-19 at 21:50.The student, Tanmay Ghonge, submitted this Dissertation for approval on 2019-02-19 at 21:56.This Dissertation was approved for publication on 2019-02-28 at 09:39.DSpace SAF Submission Ingestion Package generated from Vireo submission #13396 on 2019-08-22 at 16:19:57Made available in DSpace on 2019-08-23T20:44:32Z (GMT). No. of bitstreams: 4
GHONGE-DISSERTATION-2019.pdf: 6173436 bytes, checksum: e019c78e550dfe824345201dcfadce00 (MD5)
Supplementary movie 1.mp4: 2673428 bytes, checksum: 817416641bad1a3ab3e06c0ebad7072d (MD5)
Supplementary movie 2.mp4: 1779519 bytes, checksum: 057a1fb688c9c39fe8441ab6723ca551 (MD5)
LICENSE.txt: 4210 bytes, checksum: 9bc36e1e230870dbc2ce23553dd18cc1 (MD5)
Previous issue date: 2019-02-28Embargo set by: Seth Robbins for item 112254
Lift date: 2021-08-23T20:44:50Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 112254
Lift date: 2021-08-23T20:46:41Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 112254
Lift date: 2021-08-23T20:47:38Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 112254
Lift date: 2021-08-23T20:48:32Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 112254 on 2021-08-24T09:15:20Z
Temporal Synchronization of Sensors
No full textAdvanced automotive vehicles are based on the real-time fusion of an increasing number of automotive sensors. For precise fusion of different sensors, measurements need to be synchronized both temporally and spatially. This thesis aims to design a hardware temporal synchronization block as part of the PRISTINE systolic array accelerator project for multi-sensor data fusion. In this process, we study and address several temporal sensor synchronization issues that are characteristic of the considered system as well as any other typical sensor fusion system. First and foremost, we handle the problem of estimating the actual time of sensor measurement by exploring well-known filtering techniques such as Kalman, mean and median filters. A suitable filter is selected for implementation based on the statistical characteristics of the observed sensor cycle times, the complexity of the filters and the quality of obtained estimates. Next, we address the issue of reconstructing incoming sensor data streams according to the estimated sensor measurement times while maintaining minimal latency and synchronization error by employing an adaptive stream buffering technique utilized in distributed multimedia systems. An analysis of the effects of the stream synchronization algorithm's parameters on buffering latency and synchronization error was presented. Finally, the above synchronization solution was efficiently implemented on hardware by making certain modifications and design decisions to the algorithm. A method to evaluate the whole temporal synchronization process is proposed and the obtained results on real sensor data are presented.PRYSTINEElectrical Engineering | Circuits and System
Peak Trekking of Hierarchy Mountain for the Detection of Cerebral Aneurysm using Modified Hough Circle Transform
No full textThe Circle of Willis is in the junction of two carotid arteries and two vertebral arteries that supply the brain with nutrition. Junctions where these arteries come together may develop weak spots that can balloon out and fill with blood, creating aneurysms. These sac-like areas may leak or rupture, spilling blood into surrounding tissues which may cause artery spasm leading to potential stroke or even death. Clipping and coiling are two treatment options preferred by neurosurgeon which require proper detection of aneurysm. Medical practitioners are therefore emphasizing on the prior detection of cerebral aneurysm (CA) before rupture occurs leading to subarachnoid haemorrhage (SAH). This paper presents a novel method by application of Modified Hough Circle Transform & Peak Trekking (MHCT-PT) technique on the image extracted from Digital subtraction angiography (DSA). Experimental results have firmly substantiated that the proposed method is highly efficient in properly detecting the location, size and type of aneurysm
Multi-disciplinary Optimization of Rotor Nacelle Assemblies for Offshore Wind Farms: An Agile Systems Engineering Approach
No full textThe models with different fidelities for the siloed application of niche wind farm disciplines - rotor aerodynamics, aeroelasticity or wake aerodynamics - are prevalent in literature. These models are often used sequentially while designing a wind farm that may lead to a sub-optimal design due to their agnosticism towards the inter-disciplinary influences. This paper demonstrates the multi-disciplinary optimization of rotor nacelle assemblies for offshore wind farms. The designs of three aspects of rotor nacelle assembly are addressed - rotor blade, power density and drive train configuration - that support the development of an open-source agile systems engineering framework and allow flexibility in their utility to various stakeholders of offshore wind farms.Electrical Engineering | Sustainable Energy Technolog
An Ultrasonically-Powered System for 1.06mm<sup>3</sup> Implantable Optogenetics and Drug Delivery Dust
No full textThis brief presents an ultrasonically powered micro-system for deep tissue optogenetic stimulation. The developed system is composed of a Base for Powering and Controlling (BPC) and an implantable Dust for optogenetics and drug delivery. The Dust consists of a piezoelectric crystal, a rectifier chip, and a micro-scale custom-designed light-emitting-diode (μ LED) integrated, miniaturized, and envisioned to be used for freely moving animal studies. The proposed Dust operates in frequencies up to 5 MHz, power levels in the 0-10 mW range, achieves start-up within 1.8~μ s at 2.9 MHz operating frequency at 14.4 mW/mm2 ultrasound power density, and 98.1% chip efficiency at 2 mW input power. With the BPC implemented and attached to ( 500~μ m )3 PZT4 crystals, set to 60 V at 2.8 MHz operating frequency at 3 mm distance in demineralized water, the dust delivered up to 6 mW to its load (μ LED for optogenetics), which translates to 0.11% total system efficiency.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Bio-Electronic
