314 research outputs found
Improving Indoor Localization Using Mobile UWB Sensor and Deep Neural Networks
Accurate localization in indoor environments with ultra-wideband (UWB) technology has long attracted much attention. However, due to the presence of multipath components or non-line of sight (NLOS) propagation of the radio signals, it has been converted to a critical challenge. Existing solutions use many fixed anchors in the indoor environment. Particularly, large areas require many anchor points and in the case of unexpected events that lead to the destruction of existing infrastructures, the fixed anchor points cannot be used. In this paper, a novel localization framework based on the transmitting signal from a mobile UWB sensor on the outside of the building and its received signal regarding the modified Saleh Valenzuela (SV) channel model is presented. After preprocessing the received signals, two new procedures to reduce the ranging error caused by multipath components are proposed. In the first procedure, two machine learning algorithms including multi-layer perceptron (MLP) and support vector machine (SVM) using the extracted features from the received UWB signal time and power vectors are implemented. Moreover, in the second procedure, two deep learning algorithms including MLP and convolutional neural networks (CNNs) using the received UWB signal time and power vectors are implemented to improve the performance of the indoor localization system. The simulation results show that the architecture designed for the convolutional neural network based on the hybrid dataset (the combination of the dataset related to received UWB signal time and power vectors) provides a mean absolute error (MAE) of about 3 cm
Some new existence results for boundary value problems involving ψ-Caputo fractional derivative
This paper concerns the boundary value problem for a fractional differential equation involving a generalized Caputo fractional derivative in b−metric spaces. The used fractional operator is given by the kernel k(t, s) = ψ(t) − ψ(s) and the derivative operator 1/ψʹ(t) d/dt . Some existence results are obtained based on fixed point theorem of α-φ−Graghty contraction type mapping. In the end, we provide some illustrative examples to justify the acquired results.Publisher's Versio
Glutaraldehyde-crosslinking for improved copper absorption selectivity and chemical stability of polyethyleneimine coatings
Nano-thin coatings of glutaraldehyde (GA)-crosslinked polyethyleneimine (PEI) are extremely selective and effective in binding copper from seawater. Here it was demonstrated that GA-PEI performs significantly different from PEI. The copper-selectivity of self-assembled PEI coatings on silicon substrates was greatly improved by GA-crosslinking. After submersion in artificial seawater containing 200 ppb copper and equimolar amounts of 11 competing ions only copper and trace amounts of Zn were detected in the GA-crosslinked coatings, while for non-crosslinked PEI there was about 30% Zn present relative to copper. The coatings were demonstrated to be highly stable under acidic conditions and retained their copper-binding selectivity after repeated cycles of binding and acid-mediated elution. After self-assembly of the GA-crosslinked coating on mesoporous diatomaceous earth particles, significant amounts of copper could be extracted from 200 ppb in artificial seawater and eluted under acidic pH
Structure, Wettability, Corrosion and Biocompatibility of Nitinol Treated by Alkaline Hydrothermal and Hydrophobic Functionalization for Cardiovascular Applications
The main objective of this study is to hydrophobize nitinol (Ni-Ti alloy) for cardiovascular applications. For this purpose, medical nitinol samples were subjected to sodium hydroxide hydrothermal treatments at various temperatures, followed by hexadecyltrimethoxysilane (HDTMS) functionalization. Then, the structure, wettability, corrosion, cytocompatibility and cell adhesion of the prepared samples were evaluated. According to the results, porous blade-shaped layers of sodium titanate were formed on the substrate surface as a result of the alkaline treatment. These nano-rough features offered considerable hydrophobicity after HDTMS processing, where a maximum water contact angle of about 140° was obtained for the sample treated at 120 °C, followed by the HDTMS coating. In contrast to the individual application of the alkaline treatments, the subsequent HDTMS processing improved corrosion resistance in the simulated body fluid. Although all the samples presented appropriate cytocompatibility with respect to human umbilical vein endothelial cells, the cells did not show an adhesion tendency to the hydrophobic surfaces. It is concluded that alkaline hydrothermal and HDTMS processed nitinol can be considered for cardiovascular applications demanding hydrophobic surfaces
Fruit set and seed traits affected by N-phenyl-phetalamic acid in four grapevine (Vitis vinifera L.) cultivars
Grapes are an important horticultural crop that is popularly consumed in a variety of different forms; the fruit is eaten in at its immature stage, as ripe fruit and dried as raisins and vine leaves are also consumed. Therefore any research on ways to improve production of Iranian grapes in terms of quality and quantity is valuable. The main purpose of this study was to test the use of Phenyl Phetalamic Acid (PPA) to improve fruit set and quality. The experiment was designed as a factorial for four grapevine cultivars; 'Razeghi', 'Askari', 'Sefidaly' and 'Rishbaba' and three concentrations of PPA (0, 500, 1000 mg∙L-1). Treatments were arranged in a completely randomized design with three replications. The experiment was done in the Kashmar vineyard (Khorasan Razavi province) during 2010 spring. PPA treatment was applied by foliar spraying at the stage of 50 % anthesis. Results showed that PPA levels had a significant effect on evaluated cluster traits (weight, length and number) and berry (number, weight, length and diameter). Fruit set index (number of berries per cluster) was 263.11 for 'Sefidaly' followed by 113, 109.89 and 76.11 for 'Askari', 'Razeghi' and 'Rishbaba', respectively. 'Askari' and 'Razeghi' cultivars showed similar and insignificant reactions but their difference was significant compared to 'Rishbaba'. The effect was significant for interactions of traits for cluster, berry and seed except for number of berries per cluster. Based on these results, cluster characters were significantly and positively affected by PPA treatment at the concentration of 1000 mg∙L-1. This concentration increased fruit set by 26.2 % compared to the control in all cultivars except for Askari. The PPA concentration 500 mg∙L-1, observed as the most effective treatment for improved berry characters, provided its non-significant difference with 1000 mg∙L-1. Seed number per berry decreased significantly in 'Askari' and 'Rishbaba' at 500 mg∙L-1, which was considered positive in terms of quality. In summary, results determined that PPA had a positive effect on fruit as an auxin synergist. These improved berry characteristics are hypothesized to occur through a decrease in the dominance of apical buds that would allow more metabolites to be directed to development of fruit clusters, although further research is required.
A microfluidic approach to rapid sperm recovery from heterogeneous cell suspensions
The isolation of sperm cells from background cell populations and debris is an essential step in all assisted reproductive technologies. Conventional techniques for sperm recovery from testicular sperm extractions stagnate at the sample processing stage, where it can take several hours to identify viable sperm from a background of collateral cells such as white bloods cells (WBCs), red blood cells (RBCs), epithelial cells (ECs) and in some cases cancer cells. Manual identification of sperm from contaminating cells and debris is a tedious and time-consuming operation that can be suitably addressed through inertial microfluidics. Microfluidics has proven an effective technology for high-quality sperm selection based on motility. However, motility-based selection methods cannot cater for viable, non-motile sperm often present in testicular or epididymal sperm extractions and aspirations. This study demonstrates the use of a 3D printed inertial microfluidic device for the separation of sperm cells from a mixed suspension of WBCs, RBCs, ECs, and leukemic cancer cells. This technology presents a 36-fold time improvement for the recovery of sperm cells (> 96%) by separating sperm, RBCS, WBCs, ECs and cancer cells into tight bands in less than 5 min. Furthermore, microfluidic processing of sperm has no impact on sperm parameters; vitality, motility, morphology, or DNA fragmentation of sperm. Applying inertial microfluidics for non-motile sperm recovery can greatly improve the current processing procedure of testicular sperm extractions, simplifying the fertility outcomes for severe forms of male infertility that warrant the surgery
Analysis of Cases inWhich a Biopsy Specimen Is Positive and an Excised Lesion Is Negative for Nonmelanoma Skin Cancer
Nonmelanoma skin cancers (NMSCs), including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), are the most common types of cancer with the fastest-growing treatment costs in the United States.1 Standard treatment requires biopsy for histologic confirmation, followed by excision. Oftentimes, no residual carcinoma is detected, implying spontaneous clearance at rates reported to vary from 24% to 76%.2- 5 These types of lesions have been investigated by others2- 5 and are not fully understood. Our study aims to determine the lesion and patient characteristics that would most strongly predict a histologically negative result for an excised lesion after a biopsy specimen had positive margins
Gender, health and the 2030 agenda for sustainable development
Gender refers to the social relationships between males and females in terms of their roles, behaviours, activities, attributes
and opportunities, and which are based on different levels of power. Gender interacts with, but is distinct from, the binary categories of
biological sex. In this paper we consider how gender interacts with the 2030 agenda for sustainable development, including sustainable
development goal (SDG) 3 and its targets for health and well-being, and the impact on health equity. We propose a conceptual framework
for understanding the interactions between gender (SDG 5) and health (SDG 3) and 13 other SDGs, which influence health outcomes. We
explore the empirical evidence for these interactions in relation to three domains of gender and health: gender as a social determinant of
health; gender as a driver of health behaviours; and the gendered response of health systems. The paper highlights the complex relationship
between health and gender, and how these domains interact with the broad 2030 agenda. Across all three domains (social determinants,
health behaviours and health system), we find evidence of the links between gender, health and other SDGs. For example, education
(SDG 4) has a measurable impact on health outcomes of women and children, while decent work (SDG 8) affects the rates of occupationrelated
morbidity and mortality, for both men and women. We propose concerted and collaborative actions across the interlinked SDGs
to deliver health equity, health and well-being for all, as well as to enhance gender equality and women’s empowerment. These proposals
are summarized in an agenda for action
Gamma irradiation of ocular melanoma and lymphoma cells in the presence of gold nanoparticles: in vitro study
The aim of this work was to determine whether conjugation of cultivated choroidal melanoma and Burkitt's lymphoma cells with gold nanoparticles (GNPs) is beneficial for these series of ocular cancer patients. GNPs are radiosensitizers and can sensitize tumors to radiotherapy.This application has been examined in several tumor types, but not in choroidal melanoma. This study shows the results of in vitro study on the choroidal melanoma and also Burkitt's lymphoma cells in the presence of GNPs during continuous gamma irradiation. Cytotoxicity of GNPs were assessed for five different concentrations then cultured melanoma and Burkitt's lymphoma cells were irradiated with a Gamma source in the presence and absence of NPs. Incubation of melanoma cells with GNP concentrations below 100 μg/ml, accompanied by gamma irradiation, increased cell death (P value = 0.016). In the absence of irradiation, GNPs at these concentrations did not affect cultured melanoma cell metabolism. Reduced cell viability resulted from a significant increase in absorbed energy by the tumor. Moreover, GNP concentrations higher than 200 μg/ml induced cytotoxicity in melanoma cells. Cytotoxicity assay in GNPs-loaded Burkitt's lymphoma cells showed a slight decrease in cell viability at 50 μg/ml and clear cytotoxicity at concentrations higher than 100 μg/ml (P value = 0.035). Concentration and proper injection doses of GNPs in sensitive tissues such as the human eye are important variables yet to be determined.This is the first report of choroidal melanoma dosimetry performed in the presence of GNPs and provides valuable insights into future therapeutic approaches. Further in vitro study with more different sizes and concentrations is needed to determine the optimum size and concentration before any clinical research in this regard. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine
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