255 research outputs found
Computer experiments to determine whether over- or under-counting necessarily affects the determination of difference in cell number between experimental groups
Cataloged from PDF version of article.Computer cell counting experiments were performed in order to examine the consequences of over- or under-counting. The
three-dimensional reaggregate culture laboratory environment for cell counting was used as a model for computer simulation. The
laboratory environment for aggregate and cell sizes, numbers and spatial placement in gelatin blocks was mimicked in the
computer setup. However, in the computer, cell counting was set to be either ideally unbiased, or deliberately biased in regard to
over- or under-counting so as to compare eventual results when using the various cell counting methods. It was found that there
was no effect of the cell counting methods used in determining whether there was a significant difference in cell number between
two experimental groups. In addition, it was found that under the conditions of these simulations, the optical disector method
behaved similarly, on the average, as the ideal method of counting cell centers and in both of those cases, the average ratio
between actual cell number in a flask and estimated number was close to 1.00. © 2001 Elsevier Science B.V. All rights reserved
Impact of Lighting Arrangements and Illuminances on Different Impressions of a Room
Cataloged from PDF version of article.This study explores whether different lighting arrangements (general lighting, wall washing and cove lighting) and different illuminances (500 and 320 lux) could affect the perception of the same space. An experimental study was conducted to investigate how the qualitative aspects of space (the impressions of a space) could be enhanced with lighting. Hundred participants were first asked to choose the most suitable lighting arrangement for each impression (clarity, spaciousness, relaxation, privacy, pleasantness and order) under the 500 lux illuminance. In the second stage, they were asked to compare the two illuminances (500 and 320 lux) for the lighting arrangement they selected in the first stage. There was a statistically significant relation between impressions and lighting arrangements, also between impressions and lighting levels. Thus, different lighting arrangements and lighting levels could be used to enhance the clarity, spaciousness, relaxation, privacy, pleasantness and order of a room. The results of this study found most suitable lighting arrangements with their illuminances for each impression, which is reported in the paper
Agricultural Academy
Abstract KAYMAK, H. C., I. GUVENC and A. GUROL, 2010. Elemental analysis of different radish (Raphanus sativus L.) Cultivars by using wavelength-dispersive X-ray fluorescence spectrometry (WDXRF). Bulg. J. Agric. Sci., The aim of this work is to study the applicability of a quantitative WDXRF (Wavelength-Dispersive X-ray Fluorescence) method, for determination of minerals in radish specimens. In this study, we have quantitatively and semi-quantitatively analysed the four different radish (Raphanus sativus L.) cultivars (cvs. 'Siyah', 'Beyaz', 'Antep' and 'Iri-Kirimizi'). We have found that major elements; namely N and K; a few minor elements; Na, Mg, P, S, and Ca, and a lot of trace elements; Mn, Fe, Cu, Zn, Al, Ti, Cr, Br, Rb, Sr, Sn, Ba and La. The obtained trace element concentrations range from 0.01 to 3.24 mg per 100 g. This rapid method has been found to be a reliable technique for analyzing the mineral content in radish. At the end of this work, it was clearly said that Wavelengthdispersive X-ray fluorescence spectrometry (WDXRF) could be used for the analysis of mineral contents of radish and other vegetables
Sector Expansion and Elliptical Modeling of Blue-Gray Ovoids for Basal Cell Carcinoma Discrimination in Dermoscopy Images
Background: Blue-gray ovoids (B-GOs), a critical dermoscopic structure for basal cell carcinoma (BCC), offer an opportunity for automatic detection of BCC. Due to variation in size and color, B-GOs can be easily mistaken for similar structures in benign lesions. Analysis of these structures could afford accurate characterization and automatic recognition of B-GOs, furthering the goal of automatic BCC detection. This study utilizes a novel segmentation method to discriminate B-GOs from their benign mimics.
Methods: Contact dermoscopy images of 68 confirmed BCCs with B-GOs were obtained. Another set of 131 contact dermoscopic images of benign lesions possessing B-GO mimics provided a benign competitive set. A total of 22 B-GO features were analyzed for all structures: 21 color features and one size feature. Regarding segmentation, this study utilized a novel sector-based, non-recursive segmentation method to expand the masks applied to the B-GOs and mimicking structures. Results: Logistic regression analysis determined that blue chromaticity was the best feature for discriminating true B-GOs in BCC from benign, mimicking structures. Discrimination of malignant structures was optimal when the final B-GO border was approximated by a best-fit ellipse. Using this optimal configuration, logistic regression analysis discriminated the expanded and fitted malignant structures from similar benign structures with a classification rate as high as 96.5%.
Conclusions: Experimental results show that color features allow accurate expansion and localization of structures from seed areas. Modeling these structures as ellipses allows high discrimination of B-GOs in BCCs from similar structures in benign images
Robotic Wireless Sensor Networks
In this chapter, we present a literature survey of an emerging, cutting-edge,
and multi-disciplinary field of research at the intersection of Robotics and
Wireless Sensor Networks (WSN) which we refer to as Robotic Wireless Sensor
Networks (RWSN). We define a RWSN as an autonomous networked multi-robot system
that aims to achieve certain sensing goals while meeting and maintaining
certain communication performance requirements, through cooperative control,
learning and adaptation. While both of the component areas, i.e., Robotics and
WSN, are very well-known and well-explored, there exist a whole set of new
opportunities and research directions at the intersection of these two fields
which are relatively or even completely unexplored. One such example would be
the use of a set of robotic routers to set up a temporary communication path
between a sender and a receiver that uses the controlled mobility to the
advantage of packet routing. We find that there exist only a limited number of
articles to be directly categorized as RWSN related works whereas there exist a
range of articles in the robotics and the WSN literature that are also relevant
to this new field of research. To connect the dots, we first identify the core
problems and research trends related to RWSN such as connectivity,
localization, routing, and robust flow of information. Next, we classify the
existing research on RWSN as well as the relevant state-of-the-arts from
robotics and WSN community according to the problems and trends identified in
the first step. Lastly, we analyze what is missing in the existing literature,
and identify topics that require more research attention in the future
Interference management for moving networks in ultra-dense urban scenarios
The number of users relying on broadband wireless connectivity while riding public transportation vehicles is increasing significantly. One of the promising solutions is to deploy moving base stations on public transportation vehicles to form moving networks (MNs) that serve these vehicular users inside the vehicles. In this study, we investigated the benefits and challenges in deploying MNs in ultra-dense urban scenarios. We identified that the key challenge limiting the performance of MNs in ultra-dense urban scenarios is inter-cell interference, which is exacerbated by the urban canyon effects. To address this challenge, we evaluated different inter-cell interference coordination and multi-antenna interference suppression techniques for MNs. We showed that in using MNs together with effective interference management approaches, the quality of service for users in vehicles can be significantly improved, with negligible impacts on the performance of regular outdoor users
The Redox State of Transglutaminase 2 Controls Arterial Remodeling
While inward remodeling of small arteries in response to low blood flow, hypertension, and chronic vasoconstriction depends on type 2 transglutaminase (TG2), the mechanisms of action have remained unresolved. We studied the regulation of TG2 activity, its (sub) cellular localization, substrates, and its specific mode of action during small artery inward remodeling. We found that inward remodeling of isolated mouse mesenteric arteries by exogenous TG2 required the presence of a reducing agent. The effect of TG2 depended on its cross-linking activity, as indicated by the lack of effect of mutant TG2. The cell-permeable reducing agent DTT, but not the cell-impermeable reducing agent TCEP, induced translocation of endogenous TG2 and high membrane-bound transglutaminase activity. This coincided with inward remodeling, characterized by a stiffening of the artery. The remodeling could be inhibited by a TG2 inhibitor and by the nitric oxide donor, SNAP. Using a pull-down assay and mass spectrometry, 21 proteins were identified as TG2 cross-linking substrates, including fibronectin, collagen and nidogen. Inward remodeling induced by low blood flow was associated with the upregulation of several anti-oxidant proteins, notably glutathione-S-transferase, and selenoprotein P. In conclusion, these results show that a reduced state induces smooth muscle membrane-bound TG2 activity. Inward remodeling results from the cross-linking of vicinal matrix proteins, causing a stiffening of the arterial wall
Quantitative PCR of ear discharge from Indigenous Australian children with acute otitis media with perforation supports a role for Alloiococcus otitidis as a secondary pathogen
Otitis media is endemic in remote Indigenous communities of Australia’s Northern Territory. Alloiococcus otitidis is an outer ear commensal and putative middle ear pathogen that has not previously been described in acute otitis media (AOM) in this population. The aims of this study were to determine the presence, antibiotic susceptibility and bacterial load of A. otitidis in nasopharyngeal and ear discharge swabs collected from Indigenous Australian children with AOM with perforation.Financial support for this study was provided by the Channel 7 Children’s Research Foundation; The Trust Foundation; and the National Health and Medical Research Council (Australia)
Taxonomy of fundamental concepts of localization in cyber-physical and sensor networks
Localization is a fundamental task in Cyber-Physical Systems (CPS), where data is tightly coupled with the environment and the location where it is generated. The research literature on localization has reached a critical mass, and several surveys have also emerged. This review paper contributes on the state-of-the-art with the proposal of a new and holistic taxonomy of the fundamental concepts of localization in CPS, based on a comprehensive analysis of previous research works and surveys. The main objective is to pave the way towards a deep understanding of the main localization techniques, and unify their descriptions. Furthermore, this review paper provides a complete overview on the most relevant localization and geolocation techniques. Also, we present the most important metrics for measuring the accuracy of localization approaches, which is meant to be the gap between the real location and its estimate. Finally, we present open issues and research challenges pertaining to localization. We believe that this review paper will represent an important and complete reference of localization techniques in CPS for researchers and practitioners and will provide them with an added value as compared to previous surveys
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