131 research outputs found
Procedimento per la generazione e l'analisi di segnali di elettrochemiluminescenza e relativo sistema
La presente invenzione si riferisce a un procedimento per la generazione e l‟analisi di segnali di elettrochemiluminescenza, che comprende le operazioni di generare uno stimolo in una cella elettrochimica comprendente un elettrodo di lavoro comprendente nanotubi di carbonio in contatto con una soluzione da misurare, cui è applicato detto stimolo, e rilevare e analizzare un segnale di elettrochemiluminescenza rappresentativo di radiazione di elettrochemiluminescenza emessa da detta soluzione in risposta a detto stimol
A “Plant-Wearable System” for Its Health Monitoring by Intra- and Interplant Communication
A step forward in smart agriculture is moving to direct monitoring plants and crops instead of their environment. Understanding plant status is crucial in improving food production and reducing the usage of water and chemicals in agriculture. Here, we propose a “plant-wearable,” low-cost, and low-power method to measure in-vivo green plant stem frequency as the indicator for plant watering stress status. Our method is based on measuring the frequency of a digital signal obtained with a relaxation oscillator where the plant is a part of the feedback loop. The frequency was correlated with the soil water potential, used as a critical indicator of plant water stress, and an 85% correlation was found. In this way, the measuring system matches all the requirements of smart agriculture and Internet of Things (IoT): ultra-low-cost, low-complexity, ultra-low-power, and small sizes, introducing the concept of wearability in plant monitoring. The proposed solution exploits the plant and the soil as a communication channel: the signal carrying the plant watering stress status information is transmitted to a receiving system connected to a different plant. The system's current consumption is lower than 50 μμ A during the transmission in the plant and 40 mA for wireless communication. During inactivity periods, the total current consumption is lower than 15 μμ A. Another important aspect is that the system has to be energy autonomous. Our proposal is based on energy harvesting solutions from multiple sources: solar cells and plant microbial fuel cells. This way, the system is batteryless, thanks to supercapacitors as a storage element. The system can be deployed in the fields and used to monitor plants directly in their environment
Electrical Impedance-Based Characterization of Hepatic Tissue with Early-Stage Fibrosis
Liver fibrosis is a key pathological precondition for hepatocellular carcinoma in which
the severity is confidently correlated with liver cancer. Liver fibrosis, characterized by gradual cell
loss and excessive extracellular matrix deposition, can be reverted if detected at the early stage.
The gold standard for staging and diagnosis of liver fibrosis is undoubtedly biopsy. However,
this technique needs careful sample preparation and expert analysis. In the present work, an ex
vivo, minimally destructive, label-free characterization of liver biopsies is presented. Through a
custom-made experimental setup, liver biopsies of bile-duct-ligated and sham-operated mice were
measured at 8, 15, and 21 days after the procedure. Changes in impedance were observed with the
progression of fibrosis, and through data fitting, tissue biopsies were approximated to an equivalent
RC circuit model. The model was validated by means of 3D hepatic cell culture measurement, in
which the capacitive part of impedance was proportionally associated with cell number and the
resistive one was proportionally associated with the extracellular matrix. While the sham-operated
samples presented a decrease in resistance with time, the bile-duct-ligated ones exhibited an increase
in this parameter with the evolution of fibrosis. Moreover, since the largest difference in resistance
between healthy and fibrotic tissue, of around 2 kW, was found at 8 days, this method presents great
potential for the study of fibrotic tissue at early stages. Our data point out the great potential of
exploiting the proposed needle setup in clinical applications
In-vivo monitoring for electrical expression of plant living parameters by an impedance lab system
We present a complete in-lab system to monitor the plant and its surrounding environment. The plant impedance is directly measured in a continuous manner, while, simultaneously surrounding environment parameters known to affect plant status, are monitored. This is done combining a new in-vivo direct measurement of the plant together with an embedded system using available sensor technology and a designated interface for continuous data acquisition. Furthermore, the next versions this system can be deployed as a field monitoring device, with simple adaptations
Live Demonstration: Wireless Device for Clinical Pulse Wave Velocity Evaluations
This Live Demonstration presents a low-cost wireless
integrated device for clinically evaluating Pulse Wave Velocity
(PWV). The system comprises two pen-shaped probes with
a high-precision MEMS force sensor on their tips and a
base/charging station. The two probes are placed on the femoral
and carotid arterial sites and send the pulse wave signals to
the base/charging station via Bluetooth. A PC GUI displays the
signals and calculates in real-time the PVW value. The visitors
can see a real PWV measurement on a dedicated test subject or
experience, in the first person, the arterial pulse assessment on
their carotid after proper probe sterilization
One-Dimensional ZnO/Gold Junction for Simultaneous and Versatile Multisensing Measurements
The sensing capabilities of zinc oxide nano/micro-structures have been widely investigated and these structures are frequently used in the fabrication of cutting-edge sensors. However, to date, little attention has been paid to the multi-sensing abilities of this material. In this work, we present an efficient multisensor based on a single zinc oxide microwire/gold junction. The device is able to detect in real time three different stimuli, UV-VIS light, temperature and pH variations. This is thanks to three properties of zinc oxide its photoconductive response, pyroelectricity and surface functionalization with amino-propyl groups, respectively. The three stimuli can be detected either simultaneously or in a sequence/random order. A specific mathematical tool was also developed, together with a design of experiments (DoE), to predict the performances of the sensor. Our micro-device allows reliable and versatile real-time measurements of UV-VIS light, temperature and pH variations. Therefore, it shows great potential for use in the field of sensing for living cell cultures
- …