scholarly journals Microfluidic-Based Oxygen (O2) Sensors for On-Chip Monitoring of Cell, Tissue and Organ Metabolism

Biosensors ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 6
Author(s):  
Mostafa Azimzadeh ◽  
Patricia Khashayar ◽  
Meitham Amereh ◽  
Nishat Tasnim ◽  
Mina Hoorfar ◽  
...  
Keyword(s):  
Electrochemical Sensors ◽  
Cell Metabolism ◽  
Portable Devices ◽  
Comprehensive Overview ◽  
Important Indicator ◽  
Advantages And Disadvantages ◽  
Cell Tissue ◽  
On Chip ◽  
Transducer Type ◽  
O2 Sensing

Oxygen (O2) quantification is essential for assessing cell metabolism, and its consumption in cell culture is an important indicator of cell viability. Recent advances in microfluidics have made O2 sensing a crucial feature for organ-on-chip (OOC) devices for various biomedical applications. OOC O2 sensors can be categorized, based on their transducer type, into two main groups, optical and electrochemical. In this review, we provide an overview of on-chip O2 sensors integrated with the OOC devices and evaluate their advantages and disadvantages. Recent innovations in optical O2 sensors integrated with OOCs are discussed in four main categories: (i) basic luminescence-based sensors; (ii) microparticle-based sensors; (iii) nano-enabled sensors; and (iv) commercial probes and portable devices. Furthermore, we discuss recent advancements in electrochemical sensors in five main categories: (i) novel configurations in Clark-type sensors; (ii) novel materials (e.g., polymers, O2 scavenging and passivation materials); (iii) nano-enabled electrochemical sensors; (iv) novel designs and fabrication techniques; and (v) commercial and portable electrochemical readouts. Together, this review provides a comprehensive overview of the current advances in the design, fabrication and application of optical and electrochemical O2 sensors.

Efficient Instruction and Data Caching for High Performance Embedded Processors

1970 ◽  
pp. 9
Author(s):  
A. Ferrerón Labari ◽  
D. Suárez Gracia ◽  
V. Viñals Yúfera
Keyword(s):  
Embedded Systems ◽  
Power Consumption ◽  
Low Power ◽  
Interconnection Networks ◽  
High Performance ◽  
Critical Issue ◽  
Content Management ◽  
Structure Design ◽  
Portable Devices ◽  
On Chip

In the last years, embedded systems have evolved so that they offer capabilities we could only find before in high performance systems. Portable devices already have multiprocessors on-chip (such as PowerPC 476FP or ARM Cortex A9 MP), usually multi-threaded, and a powerful multi-level cache memory hierarchy on-chip. As most of these systems are battery-powered, the power consumption becomes a critical issue. Achieving high performance and low power consumption is a high complexity challenge where some proposals have been already made. Suarez et al. proposed a new cache hierarchy on-chip, the LP-NUCA (Low Power NUCA), which is able to reduce the access latency taking advantage of NUCA (Non-Uniform Cache Architectures) properties. The key points are decoupling the functionality, and utilizing three specialized networks on-chip. This structure has been proved to be efficient for data hierarchies, achieving a good performance and reducing the energy consumption. On the other hand, instruction caches have different requirements and characteristics than data caches, contradicting the low-power embedded systems requirements, especially in SMT (simultaneous multi-threading) environments. We want to study the benefits of utilizing small tiled caches for the instruction hierarchy, so we propose a new design, ID-LP-NUCAs. Thus, we need to re-evaluate completely our previous design in terms of structure design, interconnection networks (including topologies, flow control and routing), content management (with special interest in hardware/software content allocation policies), and structure sharing. In CMP environments (chip multiprocessors) with parallel workloads, coherence plays an important role, and must be taken into consideration.

A Review of Drug Side Effect Identification Methods

2020 ◽  
Vol 26 (26) ◽  
pp. 3096-3104 ◽  
Author(s):  
Shuai Deng ◽  
Yige Sun ◽  
Tianyi Zhao ◽  
Yang Hu ◽  
Tianyi Zang
Keyword(s):  
Side Effects ◽  
Future Research ◽  
Drug Side Effects ◽  
Important Indicator ◽  
Advantages And Disadvantages ◽  
Key Points ◽  
Network Methods ◽  
Future Research Directions ◽  
The One ◽  
Approved Drugs

Drug side effects have become an important indicator for evaluating the safety of drugs. There are two main factors in the frequent occurrence of drug safety problems; on the one hand, the clinical understanding of drug side effects is insufficient, leading to frequent adverse drug reactions, while on the other hand, due to the long-term period and complexity of clinical trials, side effects of approved drugs on the market cannot be reported in a timely manner. Therefore, many researchers have focused on developing methods to identify drug side effects. In this review, we summarize the methods of identifying drug side effects and common databases in this field. We classified methods of identifying side effects into four categories: biological experimental, machine learning, text mining and network methods. We point out the key points of each kind of method. In addition, we also explain the advantages and disadvantages of each method. Finally, we propose future research directions.

scholarly journals State-of-the-Art Software-Based Remote Attestation: Opportunities and Open Issues for Internet of Things

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1598
Author(s):  
Sigurd Frej Joel Jørgensen Ankergård ◽  
Edlira Dushku ◽  
Nicola Dragoni
Keyword(s):  
Internet Of Things ◽  
Smart Cities ◽  
Cyber Attacks ◽  
Resource Constrained ◽  
Remote Attestation ◽  
Comprehensive Overview ◽  
Research Issues ◽  
Advantages And Disadvantages ◽  
Iot Devices ◽  
Specialized Hardware

The Internet of Things (IoT) ecosystem comprises billions of heterogeneous Internet-connected devices which are revolutionizing many domains, such as healthcare, transportation, smart cities, to mention only a few. Along with the unprecedented new opportunities, the IoT revolution is creating an enormous attack surface for potential sophisticated cyber attacks. In this context, Remote Attestation (RA) has gained wide interest as an important security technique to remotely detect adversarial presence and assure the legitimate state of an IoT device. While many RA approaches proposed in the literature make different assumptions regarding the architecture of IoT devices and adversary capabilities, most typical RA schemes rely on minimal Root of Trust by leveraging hardware that guarantees code and memory isolation. However, the presence of a specialized hardware is not always a realistic assumption, for instance, in the context of legacy IoT devices and resource-constrained IoT devices. In this paper, we survey and analyze existing software-based RA schemes (i.e., RA schemes not relying on specialized hardware components) through the lens of IoT. In particular, we provide a comprehensive overview of their design characteristics and security capabilities, analyzing their advantages and disadvantages. Finally, we discuss the opportunities that these RA schemes bring in attesting legacy and resource-constrained IoT devices, along with open research issues.

Overview of existing in vitro BBB models: advantages and disadvantages, current state and future prospects

2021 ◽  
Vol 10 (3) ◽  
pp. 109-120
Author(s):  
A. I. Mosiagina ◽  
A. V. Morgun ◽  
A. B. Salmina
Keyword(s):  
Neurovascular Unit ◽  
Clinical Trial Data ◽  
Advantages And Disadvantages ◽  
The Central Nervous System ◽  
Complex Relationships ◽  
On Chip ◽  
Induced Pluripotent ◽  
Level Of Understanding

There is growing research focusing on endothelial cells as separate units of the blood-brain barrier (BBB), and on the complex relationships between different types of cells within a neurovascular unit. To conduct this type of studies, researches use vastly different in vitro BBB models. The main objective of such models is to study the BBB permeability for different molecules, and to advance the current level of understanding the mechanisms of disease and to develop methods of targeted therapy for the central nervous system. The analysis of the existing Abstract in vitro BBB models and their advantages/disadvantages was conducted using the clinical trial data obtained in Russian/foreign countries. In this review, the authors highlight the most relevant assessment parameters and propose a unified classification of in vitro BBB models. According to the performed analysis, there is a tendency to move from 2D BBB models based on semipermeable inserts to 3D BBB spheroid and microfluidic organ-on-chip models. Moreover, the use of human induced pluripotent stem cells instead of animal primary cells will make it possible to reliably scale the results obtained in vitro to conditions in vivo.

scholarly journals Internet of medical things – integrated, ultrasound-based respiration monitoring system for incubators

2020 ◽  
Author(s):  
◽  
Tareq Abdulqader
Keyword(s):  
Real Time ◽  
Respiration Rate ◽  
Surface Measurement ◽  
Time Interval ◽  
Portable Devices ◽  
Important Indicator ◽  
The Us ◽  
Respiratory Signal ◽  
Central Apnoea ◽  
Respiration Signal

The study's aim was to develop a non-contact, ultrasound (US) based respiration rate and respiratory signal monitor suitable for babies in incubators. Respiration rate indicates average number of breaths per minute and is higher in young children than adults. It is an important indicator of health deterioration in critically ill patients. The current incubators do not have an integrated respiration monitor due to complexities in its adaptation. Monitoring respiratory signal assists in diagnosing respiration rated problems such as central Apnoea that can affect infants. US sensors are suitable for integration into incubators as US is a harmless and cost-effective technology. US beam is focused on the chest or abdomen. Chest or abdomen movements, caused by respiration process, result in variations in their distance to the US transceiver located at a distance of about 0.5 m. These variations are recorded by measuring the time of flight from transmitting the signal and its reflection from the monitored surface. Measurement of this delay over a time interval enables a respiration signal to be produced from which respiration rate and pauses in breathing are determined. To assess the accuracy of the developed device, a platform with a moving surface was devised. The magnitude and frequency of its surface movement were accurately controlled by its signal generator. The US sensor was mounted above this surface at a distance of 0.5 m. This US signal was wirelessly transmitted to a microprocessor board to digitise. The recorded signal that simulated a respiratory signal was subsequently stored and displayed on a computer or an LCD screen. The results showed that US could be used to measure respiration rate accurately. To cater for possible movement of the infant in the incubator, four US sensors were adapted. These monitored the movements from different angles. An algorithm to interpret the output from the four US sensors was devised and evaluated. The algorithm interpreted which US sensor best detected the chest movements. An IoMT system was devised that incorporated NodeMcu to capture signals from the US sensor. The detected data were transmitted to the ThingSpeak channel and processed in real-time by ThingSpeak’s add-on Matlab© feature. The data were processed on the cloud and then the results were displayed in real-time on a computer screen. The respiration rate and respiration signal could be observed remotely on portable devices e.g. mobile phones and tablets. These features allow caretakers to have access to the data at any time and be alerted to respiratory complications. A method to interpret the recorded US signals to determine respiration patterns, e.g. intermittent pauses, were implemented by utilising Matlab© and ThingSpeak Server. The method successfully detected respiratory pauses by identifying lack of chest movements. The approach can be useful in diagnosing central apnoea. In central apnoea, respiratory pauses are accompanied by cessation of chest or abdominal movements. The devised system will require clinical trials and integration into an incubator by conforming to the medical devices directives. The study demonstrated the integration of IoMT-US for measuring respiration rate and respiratory signal. The US produced respiration rate readings compared well with the actual signal generator's settings of the platform that simulated chest movements.

scholarly journals THE USE OF COPPER INDICATOR ELECTRODES IN VOLTAMMETRIC ANALYSIS

2016 ◽  
Vol 11 (5) ◽  
pp. 26-41 ◽  
Author(s):  
L. Yu. Martynov ◽  
O. A. Naumova ◽  
N. K. Zaytsev ◽  
I. Yu. Lovchinovsky
Keyword(s):  
Electrochemical Sensors ◽  
Chemical Properties ◽  
Electrochemical Analysis ◽  
Voltammetric Analysis ◽  
Advantages And Disadvantages ◽  
Copper Electrodes ◽  
Inorganic Substances ◽  
Physico Chemical ◽  
Recent Trends ◽  
Solid Electrodes

The review describes the application of solid electrodes based on copper for voltammetric analysis of major classes of organic and inorganic substances over the last fifty years. Despite the fact that there are many reviews of individual solid electrodes this review offers the first comprehensive report on all forms of copper electrodes. The advantages and disadvantages of copper electrodes in comparison with electrodes made of other metals are discussed. Varieties of copper electrodes, their basic physico-chemical properties and some specific characteristics of their surface are described. The electrochemical behavior of copper in aqueous solutions and electrocatalytic mechanisms of transformations of matter on its surface are reported. Examples of the use of electrochemical copper sensors for flow-injection analysis and liquid chromatography are given. Recent trends of the use of copper micro- and nanostructured electrodes in electrochemical analysis are reviewed. The prospects of using copper as a material for the creation of new electrochemical sensors are shown.

Microsense

2016 ◽  
Vol 7 (3) ◽  
pp. 38-55
Author(s):  
Srinivasa K.G. ◽  
Ganesh Hegde ◽  
Kushagra Mishra ◽  
Mohammad Nabeel Siddiqui ◽  
Abhishek Kumar ◽  
...  
Keyword(s):  
Real Time ◽  
Nodal Point ◽  
System On Chip ◽  
Streaming Data ◽  
Portable Devices ◽  
Time Data ◽  
Unified Framework ◽  
Real Time Data ◽  
Varied Degree ◽  
On Chip

With the advancement of portable devices and sensors, there has been a need to build a universal framework, which can serve as a nodal point to aggregate data from different kinds of devices and sensors. We propose a unified framework that will provide a robust set of guidelines for sensors with varied degree of complexities connected to common set of System-on-Chip (SoC). These will help to monitor, control and visualize real time data coming from different type of sensors connected to these SoCs. We have defined a set of APIs, which will help the sensors to register with the server. These APIs will be the standard to which the sensors will comply while streaming data when connected to the client platforms.

scholarly journals Microfluidic and Micromachined/MEMS Devices for Separation, Discrimination and Detection of Airborne Particles for Pollution Monitoring

Micromachines ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 483 ◽  
Author(s):  
Daniel Puiu Poenar
Keyword(s):  
Optical Scattering ◽  
Pollution Monitoring ◽  
Detection Methods ◽  
Mems Devices ◽  
Micro Electro Mechanical Systems ◽  
Lab On Chip ◽  
Inorganic Particles ◽  
Advantages And Disadvantages ◽  
Air Quality Assessment ◽  
On Chip

Most of the microfluidics-related literature describes devices handling liquids, with only a small part dealing with gas-based applications, and a much smaller number of papers are devoted to the separation and/or detection of airborne inorganic particles. This review is dedicated to this rather less known field which has become increasingly important in the last years due to the growing attention devoted to pollution monitoring and air quality assessment. After a brief introduction summarizing the main particulate matter (PM) classes and the need for their study, the paper reviews miniaturized devices and/or systems for separation, detection and quantitative assessment of PM concentration in air with portable and easy-to-use platforms. The PM separation methods are described first, followed by the key detection methods, namely optical (scattering) and electrical. The most important miniaturized reported realizations are analyzed, with special attention given to microfluidic and micromachined or micro-electro-mechanical systems (MEMS) chip-based implementations due to their inherent capability of being integrated in lab-on-chip (LOC) type of smart microsystems with increased functionalities that can be portable and are easy to use. The operating principles and (when available) key performance parameters of such devices are presented and compared, also highlighting their advantages and disadvantages. Finally, the most relevant conclusions are discussed in the last section.

scholarly journals 3D In Vitro Human Organ Mimicry Devices for Drug Discovery, Development, and Assessment

2020 ◽  
Vol 2020 ◽  
pp. 1-41
Author(s):  
Aida Rodriguez-Garcia ◽  
Jacqueline Oliva-Ramirez ◽  
Claudia Bautista-Flores ◽  
Samira Hosseini
Keyword(s):  
Drug Discovery ◽  
Essential Role ◽  
Future Perspectives ◽  
Human Organ ◽  
Comprehensive Review ◽  
Advantages And Disadvantages ◽  
The Past ◽  
Animal Trials ◽  
On Chip

The past few decades have shown significant advancement as complex in vitro humanized systems have substituted animal trials and 2D in vitro studies. 3D humanized platforms mimic the organs of interest with their stimulations (physical, electrical, chemical, and mechanical). Organ-on-chip devices, including in vitro modelling of 3D organoids, 3D microfabrication, and 3D bioprinted platforms, play an essential role in drug discovery, testing, and assessment. In this article, a thorough review is provided of the latest advancements in the area of organ-on-chip devices targeting liver, kidney, lung, gut, heart, skin, and brain mimicry devices for drug discovery, development, and/or assessment. The current strategies, fabrication methods, and the specific application of each device, as well as the advantages and disadvantages, are presented for each reported platform. This comprehensive review also provides some insights on the challenges and future perspectives for the further advancement of each organ-on-chip device.

scholarly journals Machine Learning Applied to Diagnosis of Human Diseases: A Systematic Review

2020 ◽  
Vol 10 (15) ◽  
pp. 5135
Author(s):  
Nuria Caballé-Cervigón ◽  
José L. Castillo-Sequera ◽  
Juan A. Gómez-Pulido ◽  
José M. Gómez-Pulido ◽  
María L. Polo-Luque
Keyword(s):  
Machine Learning ◽  
Systematic Review ◽  
English Language ◽  
Data Extraction ◽  
Real Life ◽  
Human Diseases ◽  
Machine Learning Techniques ◽  
Comprehensive Overview ◽  
Advantages And Disadvantages ◽  
Journal Citation Reports

Human healthcare is one of the most important topics for society. It tries to find the correct effective and robust disease detection as soon as possible to patients receipt the appropriate cares. Because this detection is often a difficult task, it becomes necessary medicine field searches support from other fields such as statistics and computer science. These disciplines are facing the challenge of exploring new techniques, going beyond the traditional ones. The large number of techniques that are emerging makes it necessary to provide a comprehensive overview that avoids very particular aspects. To this end, we propose a systematic review dealing with the Machine Learning applied to the diagnosis of human diseases. This review focuses on modern techniques related to the development of Machine Learning applied to diagnosis of human diseases in the medical field, in order to discover interesting patterns, making non-trivial predictions and useful in decision-making. In this way, this work can help researchers to discover and, if necessary, determine the applicability of the machine learning techniques in their particular specialties. We provide some examples of the algorithms used in medicine, analysing some trends that are focused on the goal searched, the algorithm used, and the area of applications. We detail the advantages and disadvantages of each technique to help choose the most appropriate in each real-life situation, as several authors have reported. The authors searched Scopus, Journal Citation Reports (JCR), Google Scholar, and MedLine databases from the last decades (from 1980s approximately) up to the present, with English language restrictions, for studies according to the objectives mentioned above. Based on a protocol for data extraction defined and evaluated by all authors using PRISMA methodology, 141 papers were included in this advanced review.

Sign in / Sign up

Export Citation Format

Share Document