Biomedical Applications of TiO\u3csub\u3e2\u3c/sub\u3e Nanostructures: Recent Advances

Titanium dioxide (TiO2) nanostructures are one of the most plentiful compounds that have emerged in various fields of technology such as medicine, energy and biosensing. Various TiO2 nanostructures (nanotubes [NTs] and nanowires) have been employed in photoelectrochemical (PEC) biosensing applications, greatly enhancing the detection of targets. TiO2 nanostructures, used as reinforced material or coatings for the bare surface of titanium implants, are excellent additive materials to compensate titanium implants deficiencies—like poor surface interaction with surrounding tissues—by providing nanoporous surfaces and hierarchical structures. These nanostructures can also be loaded by diversified drugs—like osteoporosis drugs, anticancer and antibiotics—and used as local drug delivery systems. Furthermore, TiO2 nanostructures and their derivatives are new emerging antimicrobial agents to overcome human pathogenic microorganisms. However, like all other nanomaterials, toxicity and biocompatibility of TiO2 nanostructures must be considered. This review highlights recent advances, along with the properties and numerous applications of TiO2-based nanostructure compounds in nano biosensing, medical implants, drug delivery and antibacterial fields. Moreover, in the present study, some recent advances accomplished on the pharmaceutical applications of TiO2 nanostructures, as well as its toxicity and biocompatibility, are presented

A review on low-cost sensors compatible with open-source platforms used for life-cycle monitoring of civil structures

Lately, the need for adopting sensors in buildings and infrastructures for monitoring and inspection of the health state of those structures is increasing. This demand is due to the increasing age of the structural stock worldwide. Consequently, more economical ways of Structural Health Monitoring applications are getting huge attention. This paper presents and evaluates several low-cost electronics compatible with open-source digital technologies for static and dynamic Structural System Identification applications. Firstly, an open-source microcontroller (Arduino), the main programable logic controller, and a Raspberry pi, a small single-board computer, are introduced. Secondly, various economic sensors with diverse measurement applications, such as ultrasonic and laser ranging, acceleration, temperature, and humidity, are discussed. Thirdly, multiple experiments in different controlled ambients are applied to assess and compare their tolerances as well as advantages and disadvantages of their use, among their price. Some problems with the Arduino codes and sensor positions emerged during the installation of the sensors and the data collection process. Finally, to attain an effective manner of using these low-cost electronics, this article offers answers to the issues faced.The authors are indebted to the Spanish Ministry of Economy and Competitiveness for the funding provided through the research project BIA2017-86811-C2-1-R directed by José Turmo.This project was funded with FEDER funds. Authors are also indebted to the Secre-taria d’ Universitats i Recerca de la Generalitat de Catalunya for the funding provided through Agaur (2017 SGR 1481). It is also to be noted that funding for this research has been provided for MR. Seyedmilad Komarizadehasl by Agencia Estatal de Investigación del Ministerio de Ciencia Innovación y Universidades grant and the Fondo Social Europeo grant (PRE2018-083238).Postprint (published version

A novel low-cost inclinometer sensor based on fusion technology for structural health monitoring applications

The fundamental purpose of structural health monitoring (SHM) is to examine the accuracy of the structural health state and predict its future strength. Lately, researchers have been paying close attention to the structural damage detection process employing inclinometers. However, this technique can only be used with unique structures with a sizable Structural Health Monitoring (SHM) budget due to the high cost of inclinometers. Therefore, the use of low-cost sensors by implementing various techniques to improve their accuracy compared to high-cost precision sensors has attracted much attention for structural assessment. This paper introduces a novel, low-cost inclinometer that measures inclination by fusion technology combining gyroscopes and accelerometers. The microcontroller technology used in this gadget is an open-source Internet of Things (IoT) based platform, allowing for wireless data streaming and free commercial software for data collecting. Not only are the coding and placement issues of these sensors thoroughly explained, but detailed answers to the problems mentioned above are also provided, as well as an efficient way to assemble and prepare the sensors.Postprint (published version

Low-cost technologies used in corrosion monitoring

Globally, corrosion is the costliest cause of the deterioration of metallic and concrete structures, leading to significant financial losses and unexpected loss of life. Therefore, corrosion monitoring is vital to the assessment of structures’ residual performance and for the identification of pathologies in early stages for the predictive maintenance of facilities. However, the high price tag on available corrosion monitoring systems leads to their exclusive use for structural health monitoring applications, especially for atmospheric corrosion detection in civil structures. In this paper a systematic literature review is provided on the state-of-the-art electrochemical methods and physical methods used so far for corrosion monitoring compatible with low-cost sensors and data acquisition devices for metallic and concrete structures. In addition, special attention is paid to the use of these devices for corrosion monitoring and detection for in situ applications in different industries. This analysis demonstrates the possible applications of low-cost sensors in the corrosion monitoring sector. In addition, this study provides scholars with preferred techniques and the most common microcontrollers, such as Arduino, to overcome the corrosion monitoring difficulties in the construction industry.The authors are indebted to the projects PID2021‐126405OB‐C31 and PID2021‐126405OB‐C32 funded by FEDER funds—A Way to Make Europe and Spanish Ministry of Economy and Com‐petitiveness MICIN/AEI/10.13039/501100011033/, project PID2019‐106555RB‐I00 and project IDEAS 2.14 from Ports 4.0. It should also be noted that funding for this research was provided for Seyed‐milad Komarizadehasl by the European Social Fund and the Spanish Agencia Estatal de Investi‐gación del Ministerio de Ciencia Innovación y Universidades, grant (PRE2018‐083238).Peer ReviewedPostprint (published version

A novel wireless low-cost inclinometer made from combining the measurements of multiple MEMS gyroscopes and accelerometers

Structural damage detection using inclinometers is getting wide attention from researchers. However, the high price of inclinometers limits this system to unique structures with a relatively high structural health monitoring (SHM) budget. This paper presents a novel low-cost inclinometer, the low-cost adaptable reliable angle-meter (LARA), which combines five gyroscopes and five accelerometers to measure inclination. LARA incorporates Internet of Things (IoT)-based microcontroller technology enabling wireless data streaming and free commercial software for data acquisition. This paper investigates the accuracy, resolution, Allan variance and standard deviation of LARA produced with a different number of combined circuits, including an accelerometer and a gyroscope. To validate the accuracy and resolution of the developed device, its results are compared with those obtained by numerical slope calculations and a commercial inclinometer (HI-INC) in laboratory conditions. The results of a load test experiment on a simple beam model show the high accuracy of LARA (0.003 degrees). The affordability and high accuracy of LARA make it applicable for structural damage detection on bridges using inclinometers.The authors are indebted to the Spanish Ministry of Economy and Competitiveness for the funding provided through the research project BIA2017-86811-C2-1-R directed by José Turmo and BIA2017-86811-C2-2-R. All these projects are funded with FEDER funds. The authors are also indebted to the Secretaria d’ Universitats i Recerca de la Generalitat de Catalunya, Catalunya, Spain for the funding provided through Agaur (2017 SGR 1482). It is also to be noted that funding for this research has been provided for Seyedmilad Komarizadehasl by Spanish Agencia Estatal de Investigación del Ministerio de Ciencia Innovación y Universidades grant and the Fondo Social Europeo grant (PRE2018-083238).Peer ReviewedPostprint (published version

Periodic Limb Movements of Sleep: A Survey on Polysomnographic Characteristics of Patients with Obstructive Sleep Apnea

Background and Objective: Periodic limb movements of sleep (PLMS) and obstructive sleep apnea (OSA) are two common sleep disorders that frequently co-occur in one subject. In this study, we evaluated the polysomnographic (PSG) features of patients with OSA with and without PLMS. Materials and Methods: Patients with OSA diagnosed by PSG who referred to our sleep clinic over 2 years were studied for PLMS during a standard diagnostic sleep study. PSG features including apnea-hypopnea index (AHI), oxygen desaturation index (ODI), and sleep quality were evaluated and compared between patients with OSA with and without PLMS. Results: We evaluated 122 patients with OSA, of whom 17 had comorbid PLMS. Mean sleep quality was significantly lower in patients with PLMS compared to those without PLMS (P < 0.05). There was no significant difference in terms of mean age, gender, arousal index (AI), ODI, and apnea/hypopnea between the two groups. Conclusion: Patients with OSA with PLMS comorbidity have remarkably lower sleep quality and this finding is independent of the severity of arousals or respiratory events. Proper evaluation, diagnosis, and treatment of PLMS comorbidity in patients with OSA might improve treatment response.  

Microwave electrodynamics of the high-Tc superconductor Tl2Ba2CuO6+delta

The microwave surface resistance, Rs(w,T), and the magnetic penetration depth, ⋋(T), of a rectangular Tl₂Ba₂CuO₆+δ (Tl-2201) single crystal measured along its different crystallographic axes are reported. The measurements of the surface resistance as a function of frequency were made using a precise broadband bolometric technique, and a loop-gap resonator was employed to measure the temperature dependence of the magnetic penetration depth. Disentangling the in- and out-of-plane components of both microwave properties was accomplished by comparing the measurement results obtained for different orientations of the sample with respect to the applied magnetic field, allowing us to report, for the first time, the c-axis components of ∆⋋(T), and Rs(w,T). In particular, our results show a quadratic temperature dependence of ∆⋋c(T) in Tl-2201 which is similar to that in other anisotropic cuprates such as BSCCO, and YBCO. Furthermore, in the case of the surface resistance, a sign change in the curvature of Rc s(w) is observed. The origin of this behavior is not yet understood. The ab-plane components of both microwave properties behave similarly to those reported on other dopings of this material. The measurements of Rs(w,T) and ∆⋋(T) allow us to determine the complex conductivity of this material. Having Tc of 43 K, the sample studied here is in the middle of the overdoped side of the superconducting dome, where very few studies have been made. This particular sample possesses relatively low quasiparticle scattering rates making the interpretation of the measurement results more straightforward. The reliability of the results, current limitations, and further potential progress are also discussed.Science, Faculty ofPhysics and Astronomy, Department ofGraduat

Ultracold nitric oxide molecular plasma : characteristic response to time-varying electric fields

Not long after metastable xenon was photoionized in a magneto-optical trap, groups in Europe and North America found that similar states of ionized gas evolved spontaneously from state-selected Rydberg gases of high principal quantum number. Studies of atomic xenon and molecular nitric oxide entrained in a supersonically cooled molecular beam subsequently showed much the same final state evolved from a sequence of prompt Penning ionization and electron impact avalanche to plasma, well-described by coupled rate-equation simulations. However, measured over longer times, the molecular ultracold plasma (UCP) was found to exhibit an anomalous combination of very long lifetime and very low apparent electron temperature. In this thesis I summarize early developments in the study of UCP formed by atomic and molecular Rydberg gases, and then I detail observations as they combine to characterize properties of the nitric oxide molecular UCP that appear to call for an explanation beyond the realm of conventional plasma physics. I also explain how I leveraged a radio frequency electric field to understand the causes of classically-unexplainable behavior of our molecular system.Science, Faculty ofChemistry, Department ofGraduat

Interrogating T cell activation from molecular to cellular scales via an integrated imaging strategy

TCR signalling involves a complex network of molecular mechanisms that evolve in both time and space to elicit diverse cell outcomes. This plastic network gives rise to heterogeneity in T cell responses such that equivalent stimulatory inputs may elicit different cell reactions. This heterogeneity raises the question; how do T cells make decisions in response to stimulation? Heterogeneity in T cell stimulation-response is often recorded at the cellular scale, yet it reflects decision-making mechanisms emerging from the molecular scale, beginning with T cell receptor (TCR) signalling. Understanding T cell decision-making therefore demands concurrent assessment of molecular- and cellular-scale features in the same individual cells, allowing heterogeneity in cell responses to illuminate dependencies across scales. Here, we developed an integrated imaging and data analysis strategy to relate cellular-scale T cell responses to the nanoscale organisation of TCR signalling molecules in the same individual cells. We characterised cellular-scale activation by quantifying i) live-cell calcium signalling followed by ii) fixed diffraction-limited imaging of TCR expression and phosphorylation in the same single cells. iii) Super-resolution dSTORM imaging of the same individual cells then recorded TCR and pTCR nanoscale spatial organisation. Building a data analysis platform to connect multivariate data from these three imaging modalities enabled statistical analyses within / between spatial and temporal scales central to T cell decision-making.We delineated mathematically independent definitions of T cell and TCR cluster activation via multiparameter statistical analyses. These unmasked low rates of T cell response in activating conditions (~20%) and low rates of TCR cluster activation (~5.5%), even in responding cells. This emphasised the value of applying robust cell and cluster activity definitions to contrast explicit T cell responses - rather than performing generalised comparisons between “activating / resting” experimental conditions. Only this approach permitted detection of activated TCR cluster-enrichment in responding cells, revealing that increased cluster numbers correspond with cell activation while expected changes in activated TCR cluster properties (size, density) do not. Significantly, this unexpected disparity implies that T cell activation follows distinct rules from TCR cluster activation, underscoring the importance of the integrated multiscale assessment of T cell decision-making developed herein

Developing and validation of an inclinometer sensor based on fusion of a magnetometer, an accelerometer and a gyroscope sensor for SHM applications

Structural Health Monitoring (SHM) programs play a critical role in civil engineering, par-ticularly for evaluating safety conditions and forecasting the strength of large structures such as bridges. Therefore, employing low-cost sensors with implementing different techniques to improve their accuracy compared to high-cost accurate sensors has attracted much attention for structural assessments. In fact, with adequate code and the proper mode to utilize their features and potentials, there is a probability of acquiring valuable data from these low-cost sensors, which can provide helpful insight for the SHM systems. Hence, this study proposes the use of a low-cost circuit for angular measurements based on the fusion of an acceler-ometer, a gyroscope, and a magnetometer sensor with an Arduino board. In this study, firstly, an introduction through Arduino due and the used sensor is presented. Then angular data acquisition problems, as well as their respective solutions, are presented.The authors are indebted to the Spanish Ministry of Economy and Competitiveness for the funding pro-vided through the research project BIA2017-86811-C2-1-R directed by José Turmo and BIA2017-86811-C2-2-R, directed by Jose Antonio Lozano-Galant. All these projects are funded with FEDER funds. Authors are also indebted to the Secretaria d’ Universitats i Recerca de la Generalitat de Catalunya for the fund-ing provided through Agaur (2017 SGR 1481). It is also to be noted that funding for this research has been provided for MR. SEYEDMILAD KOMARIZADE-HASL by Agencia Estatal de Investigación del Minis-terio de Ciencia Innovación y Universidades grant and the Fondo Social Europeo grant (PRE2018-083238).Postprint (published version