The received signal strength (RSS) based Wi-Fi fingerprint technique is not only a cost-effective means for indoor positioning but also provides reliable positioning accuracy in the indoor settings. ...Thus, such positioning technique has drawn many researchers<inline-formula> <tex-math notation="LaTeX">' </tex-math></inline-formula> attention to address its several limitations like degraded positioning accuracy due to continuous changes in surrounding environment, high positioning overhead , storage overhead etc. To address these issues, we propose a novel weighted fusion based efficient clustering strategy ( WF-ECS ) for fingerprint positioning system in this paper. Our proposed technique WF-ECS computes a weighted average of the group of reference points (RPs) having similar RSS patterns and thus, creates a more perfect match between fused positional co-ordinates and RSS patterns considered for merging to a single entry. Extensive experimentation have been carried out to evaluate and compare the performances of our proposed system WF-ECS with the contemporary fingerprint positioning systems including our prior work using the simulation test bed, the dataset collected from our departmental building and also the benchmark dataset . The experimental results depict that our newly proposed technique WF-ECS can outperform the contemporary techniques in terms of positioning accuracy and positioning overhead while reducing the storage overhead in real indoor settings.
Highly fluorescent crystalline carbon nanoparticles (CNPs) have been synthesized by one step microwave irradiation of sucrose with phosphoric acid at 100 W for 3 min 40 s. This method is very simple, ...rapid and economical and hence can be used for large scale applications. The average particle sizes are 3 to 10 nm and they emit bright green fluorescence under the irradiation of UV-light. Therefore, the particles can be used as a unique material for bioimaging as well as drug delivery. To further increase the fluorescence property of the synthetic carbon nanoparticles we simply functionalized them by using different organic dyes, such as fluorescein, rhodamine B and α-naphthylamine; the maximum fluorescence intensity was observed for the particles functionalized with fluorescein. It is very interesting to note that all of those compounds show maximum fluorescence intensity at 225 nm excitation wavelength and for any excitation wavelength the peak positions are exactly same the position as that of CNPs itself, which is completely different from the individual precursors (dyes). All of the above compounds, including CNPs, have also been successfully introduced into the erythrocyte enriched fraction of healthy human blood cells with minimum cytotoxicity.
In the domain of speech recognition many methods have been proposed over time like Gaussian mixture models (GMM), GMM with universal background model (GMM-UBM framework), joint factor analysis, etc. ...i-Vector subspace modeling is one of the recent methods that has become the state of the art technique in this domain. This method largely provides the benefit of modeling both the intra-domain and inter-domain variabilities into the same low dimensional space. In this survey, we present a comprehensive collection of research work related to i-vectors since its inception. Some recent trends of using i-vectors in combination with other approaches are also discussed. The application of i-vectors in various fields of speech recognition, viz speaker, language, accent recognition, etc. is also presented. This paper should serve as a good starting point for anyone interested in working with i-vectors for speech processing in general. We then conclude the paper with a brief discussion on the future of i-vectors.
The development of point-of-care bioassays for sensitive screening of protein-based cancer biomarkers would improve the opportunity for early stage diagnosis. A strategy for a fluorescence resonance ...energy transfer (FRET)-based bioassay has been investigated that makes use of modified cellulose paper for the detection of an epithelial cell adhesion molecule (EpCAM), which is a transmembrane glycoprotein that is overexpressed in several tumors of epithelial origin. The paper matrix was a substrate for immobilized aptamer-linked quantum dots (QDs-Apt) and Cy3 labeled complementary DNA (cDNA), which served as a donor and an acceptor, respectively. Competitive binding of EpCAM displaced the cDNA, resulting in the reduction of FRET. The paper-based bioassay was able to detect EpCAM in buffer solution as well as in 10% bovine serum solution using a reaction time of no more than 60 minutes. The dynamic range was 1-100 nM in buffer with a precision better than 4%, and the limit of detection was 250 pM in buffer and 600 pM in 10% serum.
Cancer immunotherapy has shown remarkable results in various cancer types through a range of immunotherapeutic approaches, including chimeric antigen receptor-T cell (CAR-T) therapy, immune ...checkpoint blockade (ICB), and therapeutic vaccines. Despite the enormous potential of cancer immunotherapy, its application in various clinical settings has been limited by immune evasion and immune suppressive mechanisms occurring locally or systemically, low durable response rates, and severe side effects. In the last decades, the rapid advancement of nanotechnology has been aiming at the development of novel synthetic nanocarriers enabling precise and enhanced delivery of immunotherapeutics, while improving drug stability and effectiveness. Magnetic nanostructured formulations are particularly intriguing because of their easy surface functionalization, low cost, and robust manufacturing procedures, together with their suitability for the implementation of magnetically-guided and heat-based therapeutic strategies. Here, we summarize and discuss the unique features of magnetic-based nanostructures, which can be opportunely designed to potentiate classic immunotherapies, such as therapeutic vaccines, ICB, adoptive cell therapy (ACT), and in situ vaccination. Finally, we focus on how multifunctional magnetic delivery systems can facilitate the anti-tumour therapies relying on multiple immunotherapies and/or other therapeutic modalities. Combinatorial magnetic-based therapies are indeed offering the possibility to overcome current challenges in cancer immunotherapy.
Although calcium phosphate based nanomaterials are widely used in various biomedical application, the synthesis of high quality examples of such nanomaterials with controlled size and shape is ...challenging. Here, we report a single-phase approach for the length-controlled synthesis of calcium phosphate nanorods and nanowires of 2–5 nm diameter and 10–1000 nm length. The synthetic method involves the injection of tetrabutylammonium phosphate into an oleic acid solution of calcium oleate at 200–330 °C and controlling the nucleation–growth kinetics of calcium phosphate by temperature, molar ratio of calcium to phosphate, reaction time, and solvent. Nanorods are formed at a calcium to phosphate molar ratio of 2:1, and with increasing temperature, more anisotropic nanowires are formed. As the reaction progresses at a certain growth condition, the length of the nanorods and nanowires increases with time and attains a maximum, and then the length distribution becomes broad. Thus, the best-quality nanomaterials are obtained by selecting the reaction temperature and then quenching the reaction at right time. These hydrophobic nanorods and nanowires are highly soluble, can be processed like conventional high-quality hydrophobic nanoparticles, and can be transformed into water-soluble functional nanoparticles via ligand-exchange or polymer-coating approaches. To demonstrate the application potential, we have transformed synthesized hydrophobic nanorods into water-soluble nanorods via polymer coating and used them as carriers for the cellular delivery of protein. These nanorods and nanowires can be viewed as potential cellular delivery carriers.
Smartphone sensor-based pedestrian dead reckoning (PDR) systems provide a viable solution to the problem of localization in an infrastructure-less area. Step detection (SD) and step length estimation ...(SLE), being two fundamental operations of the PDR based localization technique, have drawn many researchers' attention in the recent time. Most of the existing SD and SLE methods proposed over the years, however, provide either server- or cloud-based solution that consume additional network bandwidth and suffer from increased transmission delay. Moreover, nonavailability of the inertial sensors like gyroscope, magnetometers etc. at every smartphone makes majority of the existing SLE methods less applicable to such devices. To address the above-said issues, in this paper we focus on devising an improved SLE method that would detect the pedestrian's steps and subsequently estimate the step length in real-time by processing the accelerometer data at the device itself. Our proposed method transforms the measured acceleration values along the Earth coordinate system and also applies sliding window meaning to mitigate the negative effects of the smartphone's orientation and gravitational bias on the accuracy of SD and SLE. The performances of our proposed method are evaluated in terms of accuracy for ten different users by taking the device in two different postures (handheld and trouser pocket) under two different walking modes (normal and fast) to demonstrate its efficacy. Moreover, our proposed method obtains more than 80% average accuracy for SD and also obtains more than 75% accuracy (median) for SLE for all participants under four different scenarios considered here.
Specularity segmentation in colonoscopy images is a crucial pre-processing step for efficient computational diagnosis. The presence of these specular highlights could mislead the detectors that are ...intended towards precise identification of biomarkers. Conventional methods adopted so far do not provide satisfactory results, especially in the overexposed regions. The potential of deep learning methods is still unexplored in the related problem domain. Our work aims at providing a solution for more accurate highlights segmentation to assist surgeons. In this paper, we propose a novel deep learning based approach that performs segmentation following a multi-resolution analysis. This is achieved by introducing discrete wavelet transform (DWT) into the proposed model. We replace the standard pooling layers with DWTs, which helps preserve information and circumvent the effect of overexposed regions. All analytical experiments are performed using a publicly available benchmark dataset, and an F1-score (%) of 83.10 ± 0.14 is obtained on the test set. The experimental results show that this technique outperforms state-of-the-art methods and performs significantly better in overexposed regions. The proposed model also performed superior to some deep learning models (but applied in different domains) when tested with our problem specifications. Our method provides segmentation outcomes that are closer to the actual segmentation done by experts. This ensures improved pre-processed colonoscopy images that aid in better diagnosis of colorectal cancer.
Here we report a surface modification approach for fluorescent silicon nanoparticle that transforms hydrophobic nanoparticle into water-soluble nanoparticle of high colloidal stability. The approach ...involves ring-opening polymerization of glycidol at the hydroxyl-terminated nanoparticle surface that results in a hyperbranched polyglycerol grafted silicon nanoparticle (Si-HPG). The resultant Si-HPG has 25 nm hydrodynamic diameter, low surface charge, and broad emission in the range of 450–700 nm with a fluorescence quantum yield of 6–9%. The Si-HPG has been transformed into cyclic RGD peptide functionalized nanoprobe using the conventional bioconjugation chemistry and used for specific targeting to αvβ3 integrin overexpressed cervical cancer cells and glioblastoma cells. Result shows that a silicon nanoparticle-based red fluorescent nanoprobe can be developed for in vitro/in vivo bioimaging applications.
With the advancement of image editing tools in today's world, the manipulation of images like cropping, cloning, resizing, etc., becomes an easy proposition and on the other end, checking or ...determining whether an image has been manipulated or not, becomes a great challenge. Copy-move forgery in images is the most popular tampering method in which a portion of an image is copied and pasted in some other location of the same image. The detection of copy-move forgery has become a prominent research area. This study presents a detailed review and critical discussions with pros and cons of each of copy-move forgery detection techniques from 2007 to 2017. This study also addresses the variation in databases, issues, challenges, future directions and references in this domain.
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