100 research outputs found
Face recognition-based real-time system for surveillance
The ability to automatically recognize human faces based on dynamic facial images is important in security, surveillance and the health/independent living domains. Specific applications include access control to secure environments, identification of individuals at a particular place and intruder detection. This research proposes a real-time system for surveillance using cameras. The process is broken into two steps: (1) face detection and (2) face recognition to identify particular persons. For the first step, the system tracks and selects the faces of the detected persons. An efficient recognition algorithm is then used to recognize detected faces with a known database. The proposed approach exploits the Viola-Jones method for face detection, the Kanade-Lucas-Tomasi algorithm as a feature tracker and Principal Component Analysis (PCA) for face recognition. This system can be implemented at different restricted areas, such as at the office or house of a suspicious person or at the entrance of a sensitive installation. The system works almost perfectly under reasonable lighting conditions and image depths
Piezoelectric characteristics of CMOS compatible AIN SAW resonators
In this work, we predict the surface acoustic wave characteristics by 2D COMSOL finite element modeling. The dispersion of simulated acoustic mode shapes, acoustic phase velocity and coupling coefficient were performed on a CMOS-compatible 1.4 GHz SAW resonator. C-axis oriented Aluminium Nitride (AIN) was chosen as the piezoelectric material due to its compatibility with CMOS technology and higher phase velocity. The influences of AIN thickness on electromechanical coupling coefficient and phase velocity are discussed. High acoustic velocities (v∼5220 m/s) and coupling factors (k2∼0.19%) can be observed for SAW resonator with khAIN∼ 3.9. The measurement results are found to be consistent with FEM results with deviation less than 6% for resonance frequency and phase velocity
Metrewave Galactic Plane with the uGMRT (MeGaPluG) Survey: Lessons from the Pilot Study
Context. The advent of wide-band receiver systems on interferometer arrays
enables one to undertake high-sensitivity and high-resolution radio continuum
surveys of the Galactic plane in a reasonable amount of telescope time.
However, to date, there are only a few such studies of the first quadrant of
the Milky Way that have been carried out at frequencies below 1 GHz. The Giant
Metrewave Radio Telescope (GMRT) has recently upgraded its receivers with
wide-band capabilities (now called the uGMRT) and provides a good opportunity
to conduct high resolution surveys, while also being sensitive to the extended
structures.
Aims. We wish to assess the feasibility of conducting a large-scale snapshot
survey, the Metrewave Galactic Plane with the uGMRT Survey (MeGaPluG), to
simultaneously map extended sources and compact objects at an angular
resolution lower than and a point source sensitivity of 0.15 mJy/beam.
Methods. We performed an unbiased survey of a small portion of the Galactic
plane, covering the W43/W44 regions ( and )
in two frequency bands: 300500 MHz and 550750 MHz. The 200 MHz wide-band
receivers on the uGMRT are employed to observe the target field in several
pointings, spending nearly 14 minutes on each pointing in two separate scans.
We developed an automated pipeline for the calibration, and a semi-automated
self-calibration procedure is used to image each pointing using multi-scale
CLEAN and outlier fields.
Results. We produced continuum mosaics of the surveyed region at a final
common resolution of in the two bands that have central frequencies of
400 MHz and 650 MHz, with a point source sensitivity better than 5 mJy/beam. We
plan to cover a larger footprint of the Galactic plane in the near future based
on the lessons learnt from this study. (Abridged)Comment: To be published in A&A. 13 pages, 10 figure
Determination of phenanthrene and fluoranthene in rice samples by activated carbon-based dispersive solid phase micro-extraction coupled with gas chromatography-flame ionization detector analysis
A simple dispersive solid phase micro-extraction (DSPME) based on activated carbon (AC) was performed for the determination and separation of carcinogenic polycyclic aromatic hydrocarbons (PAHs), namely phenanthrene and fluoranthene, in selected white, brown and parboiled rice samples. The extraction was coupled with gas chromatography-flame ionization detector (GC-FID) for analysis. Under the optimized conditions [amount of adsorbent (5 mg), sample volume (40 mL), type (dichloromethane), and volume of desorption solvent (300 μL)], calibration curves were found to be linear for the concentration between 10 and 1000 μg kg-1 with coefficient of determination (R2) from 0.9938 to 0.9955. The limit of detection (LOD) and limit of quantification (LOQ) were in the range of 0.11 - 0.15 μg kg-1 and 0.33 - 0.46 μg kg-1, respectively. Relative standard deviation (RSD) was less than 8.02% and 5.48% for intra-day (n = 5) and inter-day (n = 5) for the present method, respectively. High pre-concentration factor (2587 - 2866) and satisfactory recoveries (90.23 - 115.63%) were also achieved. The proposed method was found to be simple, rapid and reliable for the monitoring of PAHs in rice samples
Current State of the Science: Health Effects and Indoor Environmental Quality
Our understanding of the relationship between human health and the indoor environment continues to evolve. Previous research on health and indoor environments has tended to concentrate on discrete pollutant sources and exposures and on specific disease processes. Recently, efforts have been made to characterize more fully the complex interactions between the health of occupants and the interior spaces they inhabit. In this article we review recent advances in source characterization, exposure assessment, health effects associated with indoor exposures, and intervention research related to indoor environments. Advances in source characterization include a better understanding of how chemicals are transported and processed within spaces and the role that other factors such as lighting and building design may play in determining health. Efforts are under way to improve our ability to measure exposures, but this remains a challenge, particularly for biological agents. Researchers are also examining the effects of multiple exposures as well as the effects of exposures on vulnerable populations such as children and the elderly. In addition, a number of investigators are also studying the effects of modifying building design, materials, and operations on occupant health. Identification of research priorities should include input from building designers, operators, and the public health community
The costs, resource use, and cost-effectiveness of Clinical Nurse Specialist (CNSs) led interventions for patients with palliative care needs: a systematic review of international evidence
Background: Patients with palliative care (PC) needs do not access specialist palliative care services according to their necessities. Clinical Nurse Specialists (CNS) working across a variety of fields are playing an increasingly important role in the care of such patients, but there is limited knowledge of the extent to which their interventions are cost-effective.
Objectives: To present results from a systematic review of the international evidence on the costs, resource use and cost effectiveness of CNS led interventions for patients palliative care needs, defined as seriously ill patients and those with advanced disease or frailty who are unlikely to be cured, recover, or stabilize.
Design: Systematic review following PRISMA methodology.
Data sources: Medline, Embase, Cinahl and Cochrane library up to 2015. Studies focusing on the outcomes of CNS interventions for patients with PC needs, and including at least one economic outcome, were considered. The quality of studies was assessed using tools from the Joanna-Briggs-Institute.
Results: A total of 79 papers were included: 37 RCTs, 22 quasi-experimental studies, 7 service evaluations and other studies, and 13 economic analyses. The studies included a wide variety of interventions including clinical, support and education, as well as care coordination activities. The quality of the studies varied greatly.
Conclusions: CNSs interventions may be effective in reducing specific resource use such as hospitalizations /re-hospitalizations/admissions, length of stay, and health care costs. There is mixed evidence regarding their cost-effectiveness. Future studies should ensure that clinical nurse specialists’ roles and activities are clearly described and evaluated
Synthesis of Boron-Doped Zinc Oxide Nanosheets by Using Phyllanthus Emblica Leaf Extract: A Sustainable Environmental Applications
The use of Phyllanthus emblica (gooseberry) leaf extract to synthesize Boron-doped zinc oxide nanosheets (B-doped ZnO-NSs) is deliberated in this article. Scanning electron microscopy (SEM) shows a network of synthesized nanosheets randomly aligned side by side in a B-doped ZnO (15 wt% B) sample. The thickness of B-doped ZnO-NSs is in the range of 20–80 nm. B-doped ZnO-NSs were tested against both gram-positive and gram-negative bacterial strains including Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, and Escherichia coli. Against gram-negative bacterium (K. pneumonia and E. coli), B-doped ZnO displays enhanced antibacterial activity with 26 and 24 mm of inhibition zone, respectively. The mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), mean free path (MFP), half-value layer (HVL), and tenth value layer (TVL) of B-doped ZnO were investigated as aspects linked to radiation shielding. These observations were carried out by using a PTW® electron detector and VARIAN® irradiation with 6 MeV electrons. The results of these experiments can be used to learn more about the radiation shielding properties of B-doped ZnO nanostructures
Assessment of left ventricular function by three-dimensional echocardiography.
Accurate determination of LV volume, ejection fraction and segmental wall
motion abnormalities is important for clinical decision-making and
follow-up assessment. Currently, echocardiography is the most common used
method to obtain this information. Three-dimensional echocardiography has
shown to be an accurate and reproducible method for LV quantitation,
mainly by avoiding the use of geometric assumptions. In this review, we
describe various methods to acquire a 3D-dataset for LV volume and wall
motion analysis, including their advantages and limitations. We provide an
overview of studies comparing LV volume and function measurement by
various gated and real-time methods of acquisition compared to magnetic
resonance imaging. New technical improvements, such as automated
endocardial border detection and contrast enhancement, will make accurate
on-line assessment with little operator interaction possible in the near
future
Assessment of normal tricuspid valve anatomy in adults by real-time three-dimensional echocardiography
Background: The tricuspid valve (TV) is a complex structure. Unlike the aortic and mitral valve it is not possible to visualize all TV leaflets simultaneously in one cross-sectional view by standard two-dimensional echocardiography (2DE) either transthoracic or transesophageal due to the position of TV in the far field. Aim: Quantitative and qualitative assessment of the normal TV using real-time 3-dimensional echocardiography (RT3DE). Methods: RT3DE was performed for 100 normal adults (mean age 30 ± 9 years, 65% males). RT3DE visualization was evaluated by 4-point score (1: not visualized, 2: inadequate, 3: sufficient, and 4: excellent). Measurements included TV annulus diameters (TAD), TV area (TVA), and commissural width. Results: In 90% of patients with good 2DE image quality, it was possible to analyse TV anatomy by RT3DE. A detailed anatomical structure including unique description and measurement of tricuspid annulus shape and size, TV leaflets shape, and mobility, and TV commissural width were obtained in majority of patients. Identification of each TV leaflet as seen in the routine 2DE views was obtained. Conclusion: RT3DE of the TVis feasible in a large number of patients. RT3DE may add to functional 2DE data in description of TV anatomy and providing highly reproducible and actual reality (anatomical and functional) measurements
Predicting clinically unrecognized coronary artery disease: use of two- dimensional echocardiography
<p>Abstract</p> <p>Background</p> <p>2-D Echo is often performed in patients without history of coronary artery disease (CAD). We sought to determine echo features predictive of CAD.</p> <p>Methods</p> <p>2-D Echo of 328 patients without known CAD performed within one year prior to stress myocardial SPECT and angiography were reviewed. Echo features examined were left ventricular and atrial enlargement, LV hypertrophy, wall motion abnormality (WMA), LV ejection fraction (EF) < 50%, mitral annular calcification (MAC) and aortic sclerosis/stenosis (AS). High risk myocardial perfusion abnormality (MPA) was defined as >15% LV perfusion defect or multivessel distribution. Severe coronary artery stenosis (CAS) was defined as left main, 3 VD or 2VD involving proximal LAD.</p> <p>Results</p> <p>The mean age was 62 ± 13 years, 59% men, 29% diabetic (DM) and 148 (45%) had > 2 risk factors. Pharmacologic stress was performed in 109 patients (33%). MPA was present in 200 pts (60%) of which, 137 were high risk. CAS was present in 166 pts (51%), 75 were severe. Of 87 patients with WMA, 83% had MPA and 78% had CAS. Multivariate analysis identified age >65, male, inability to exercise, DM, WMA, MAC and AS as independent predictors of MPA and CAS. Independent predictors of high risk MPA and severe CAS were age, DM, inability to exercise and WMA.</p> <p>2-D echo findings offered incremental value over clinical information in predicting CAD by angiography. (Chi square: 360 vs. 320 p = 0.02).</p> <p>Conclusion</p> <p>2-D Echo was valuable in predicting presence of physiological and anatomical CAD in addition to clinical information.</p
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