In this work, we have designed, constructed, and evaluated simple, inexpensive open-source data acquisition systems based on various analog-to-digital converter modules (ADS 1115, MCP 3424, LTC 2400, with resolution from 16 to 24-bit) and a miniature Arduino Nano ™ microcontroller. The constructed data acquisition systems provide excellent performance and are comparable to a commercial, 24-bit device. We provide full schematics and corresponding source codes so that analytical chemists can easily construct any of the developed systems without extensive electronic or programming knowledge. The 24-bit LTC 2400 based device provided the best and comparable performance to a commercial, high-end 24-bit sigma to delta converter (ORCA 2800) at a fraction of cost (less than 50 USD compared to 870 USD for the commercial counterpart). The excellent performance was verified using a capillary electrophoresis system with contactless conductivity detection and separation of inorganic ions in clinical skin wipe and tap water samples.
- Keywords
- Arduino, Capillary electrophoresis, Data acquisition, Microscale separations, Open source hardware and software,
- MeSH
- Electric Conductivity MeSH
- Electrophoresis, Capillary * MeSH
- Ions MeSH
- Software * MeSH
- Water MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Ions MeSH
- Water MeSH
BACKGROUND: In-house built capillary electrophoresis (CE) systems represent a significant share of laboratory instrumentation. In most of these instruments, sample injection is effected manually with low to moderate precision and requires skilled operators. Although few automated samplers have been previously developed, typically only one sample at a time can be injected. If a series of samples is to be analyzed, manual intervention is required. In the present work, we developed and constructed a fully automated, open source, CE autosampler, able to handle up to 14 different samples that can be used as a modular component of any in-house built CE instrument. RESULTS: An inexpensive, 3D printed, open source, autosampler for CE was developed. The autosampler consists of two parts: an injection unit with carousel containing sample and electrolyte vials and a flushing unit, containing a miniature pressure/vacuum pump. The autosampler is operated by an Arduino Mega microcontroller and an Arduino code written in the laboratory. The injection sequence is entered through a keypad and LCD display by the user. The instrument can operate autonomously for extended periods of time. It was used for fully automated analysis and/or calibration of up to 14 samples with excellent injection repeatability reaching less than 2.7% RSD for peak areas. The sampler performance was tested with two independently built CE instruments, a CE system with contactless conductivity detection (C4D) and a CE system with laser induced fluorescence (LIF) detector. SIGNIFICANCE AND NOVELTY: A novel, 3D printed, Arduino-based autosampler for CE was developed. The autosampler allows autonomous hydrodynamic injection of up to 14 different samples with fully programmable injection sequence, including capillary flushing and high voltage and data acquisition control. It provides the missing instrumental sampling setup for laboratory made CE instruments. It can be simply constructed based on the open-source blueprints in any laboratory and be a useful and time-saving add-on to any modular CE instrument.
- Keywords
- Arduino, Autosampler, Capillary electrophoresis, Open source hardware and software,
- Publication type
- Journal Article MeSH
Temperature transducers are commonly used to monitor process parameters that are controlled by various types of industrial controllers. The purpose of this study is to design and model a simple microcontroller-based acoustic temperature transducer based on the variations of resonance conditions in a cylindrical resonance tube. The transducer's operation is based on the generation of an acoustic standing wave in the free resonance mode of generation within a cylindrical resonance tube which is converted into a train of pulses using Schmitt trigger circuit. The frequency of the generated standing wave (i.e., the train of pulses) is measured by the Arduino Uno microcontroller, where a digital pin is used to acquire pulses that are counted using a build-in software function in an Arduino IDE environment. Experimental results are performed for three sizes of diameters to investigate the effect of the diameter of resonance tube on the obtained results. The maximum nonlinearity error according to Full-Scale Deflection (FSD) is about 2.3 percent, and the relative error of the transducer is evaluated using experimental findings and the regression model. The circuit simplicity and design of the suggested transducer, as well as the linearity of its measurements, are notable.
- Keywords
- Arduino Uno, acoustic resonance, standing wave, temperature measurement,
- MeSH
- Acoustics * MeSH
- Transducers MeSH
- Temperature MeSH
- Vibration MeSH
- Sound * MeSH
- Publication type
- Journal Article MeSH
This article presents an open-source device illustrating the well-known magnetic levitation experiment. The uniqueness of this particular device lies in its exceptionally small dimensions, affordability and availability, which makes it a perfect design for take-home experiments for education but it can also serve as a referential design for testing various control algorithms in research. In addition, this paper provides a comprehensive hardware design for reproducibility along with the detailed derivation of the mathematical model, system identification and validation. Moreover, the introduced hardware comes with an easy-to-use open-source application programming interface in C/C++ for the Arduino IDE, Simulink and CircuitPython. REXYGEN, another environment similar to Simulink, had also been used to demonstrate the capabilities of the MagnetoShield.
- Keywords
- Arduino, control education, magnetic levitation, mechatronics, open hardware,
- Publication type
- Journal Article MeSH
The research presented here focuses on the development of a 3D printed wind tunnel and the relevant equipment to be used for calibrating bi-directional velocity probes (BDVP). BDVP are equipment to be used for measuring velocity flow by determining the pressure difference of hot gases generated during fires. The manufactured probes require calibration to determine the calibration factor. The calibration is usually performed in wind tunnels which can be difficult to access due to costs, complexity and the various pieces of equipment required. The aim of the current study is to develop and assemble an inexpensive and easy-to-build bench-scale wind tunnel, with a data-logging system and fan control functionalities for fast and effective calibration of BDVP. A 3D printer with a PET-G filament is used, able to produce parts for the wind tunnel system which are durable and easy to handle and assemble. The system additionally includes an Arduino-based measuring unit with a hot-wire anemometer and temperature correction: Rev. P. This takes precise measurements; continuously logging data on a computer through a USB interface and capable of saving data on an SD card. This design provides users with parameters of velocity flow up to 4 m/s with standard deviation of 1.2 % and turbulence intensity of 1 %. The main advantages of this wind tunnel are its simplicity to build and portability.
- Keywords
- 3D printing, Arduino, Bi-Directional Velocity Probe, Fire Engineering, Velocity, Wind Tunnel,
- Publication type
- Journal Article MeSH
In this paper, we present a novel polylactic-acid/flax-composite substrate and the implementation of a demonstrator: a microcontroller board based on commercial design. The substrate is developed for printed circuit board (PCB) applications. The pre-preg is biodegradable, reinforced, and flame-retarded. The novel material was developed to counter the increasing amount of e-waste and to improve the sustainability of the microelectronics sector. The motivation was to present a working circuit in commercial complexity that can be implemented on a rigid substrate made of natural, bio-based materials with a structure very similar to the widely used Flame Retardant Class 4 (FR4) substrate at an early technological readiness level (2-3). The circuit design is based on the Arduino Nano open-source microcontroller board design so that the demonstration could be programmable and easy to fit into education, IoT applications, and embedded designs. During the work, the design was optimized at the level of layout. The copper-clad pre-preg was then prepared and processed with subtractive printed wiring technology and through hole plating. The traditional surface mounting methodology was applied for assembly. The resulting yield of PCB production was around 50%. Signal analysis was successful with analogue data acquisition (voltage) and low-frequency (4 kHz) tests, indistinguishable from sample FR4 boards. Eventually, the samples were subjected to highly accelerated stress test (HAST). HAST tests revealed limitations compared to traditional FR4 printed circuit materials. After six cycles, the weight loss was around 30% in the case of PLA/Flax, and as three-point bending tests showed, the possible ultimate strength (25 MPa at a flexural state) was reduced by 80%. Finally, the sustainability aspect was assessed, where we found that ∼95 vol% and ∼90 wt% of the traditional substrate can be substituted, significantly easing the load of waste on the environment.
- Keywords
- Arduino Nano, PCB, PLA composite, biodegradable, commercial electronics, educational electronics, single-board microcontroller,
- Publication type
- Journal Article MeSH
PURPOSE: People chronically infected with hepatitis C virus (HCV) have diminished patient-reported outcomes (PROs). This study aimed to compare the impact of elbasvir/grazoprevir (EBR/GZR) treatment versus sofosbuvir with pegylated interferon and ribavirin (SOF/PR) on changes in PROs: 1) during the treatment period and 2) at posttreatment follow-up. PATIENTS AND METHODS: PRO data collected during the Phase III C-EDGE Head-2-Head (H2H) open-label study was analyzed. In this trial, patients infected with HCV were randomized 1:1 to receive either EBR/GZR or SOF/PR for 12 weeks. Patients self-administered the Short Form-36 version 2 (SF-36v2®) Health Survey Acute (1-week recall) Form and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) Scale at baseline, during treatment, and posttreatment. Between-group differences in mean change of PRO scores from baseline were estimated during the treatment period and also at the posttreatment follow-up. Effect sizes were calculated to evaluate if the detected change in mean PRO scores is clinically meaningful between groups. RESULTS: There were 255 patients (99.2% White, 54.1% female, 74.9% treatment naïve) included in the analysis. During the treatment period, significant declines in SF-36v2 scores were observed across all domains for the SOF/PR group. Compared to the SOF/PR group, the EBR/GZR group reported more improvement in scores across all SF-36v2 domain scores at the end of the treatment period. At treatment week 12, the between-group differences for 6 out of the 8 domain scores for these patients reflected at least moderate effects (effect sizes >0.5). No significant between-group differences in change in SF-36v2 scores from baseline were detected posttreatment. The decline in SF-36v2 scores observed during the treatment period for the SOF/PR group returned to near baseline scores or above posttreatment. Treatment with EBR/GZR did not impact fatigue scores, but treatment with SOF/PR led to increased fatigue scores during treatment which resolved by posttreatment follow-up week 12. CONCLUSION: This study demonstrated that HCV treatment with EBR/GZR resulted in a significantly better PRO profile as compared to SOF/PR. PROs are an important consideration as worsening PROs experienced during treatment may negatively influence adherence and ultimately contribute to an unfavorable clinical outcome. CLINICALTRIALSGOV IDENTIFIER: NCT02358044.
- Keywords
- direct-acting antivirals, fatigue, health-related quality of life, hepatitis, patient-reported outcomes,
- Publication type
- Journal Article MeSH
Environmental screening is essential due to the increased occurrence of harmful substances in the environment. Open Meter Duo (OMD) is an open-source field photo/fluorimeter that uses an RGB diode that imitates a color according to the selected wavelength and uses a UV LED from the security kit diode as an excitation light source. The prepared PCB shield with a 3D-printed aperture was connected to Arduino UNO R4 WiFi. This system was used for the fluorescent detection of cholinesterase activity with the indoxyl acetate method. Carbofuran-a toxic pesticide-and donepezil-a drug used to treat Alzheimer's disease-were tested as model inhibitors of cholinesterase activity. The limit of detection of indoxyl acetate was 11.6 μmol/L, and the IC50 values of the inhibitors were evaluated. This system is optimized for wireless use in field analysis with added cloud support and power source. The time of analysis was 5 min for the fluorimetric assay and 20 min for the optional photometric assay. The time of field operation was approximately 4 h of continuous measurement. This system is ready to be used as a cheap and easy control platform for portable use in drug control and point-of-care testing.
- Keywords
- 3D printing, Arduino, cholinesterase, fluorimetry, low cost, portable, remote sensing,
- MeSH
- Alzheimer Disease * MeSH
- Cholinesterase Inhibitors therapeutic use MeSH
- Cholinesterases therapeutic use MeSH
- Donepezil therapeutic use MeSH
- Fluorometry MeSH
- Humans MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Cholinesterase Inhibitors MeSH
- Cholinesterases MeSH
- Donepezil MeSH
BACKGROUND & AIMS: The literature regarding enteral nutrition and mortality in older frail people is limited and still conflicting. Moreover, the potential role of comprehensive geriatric assessment is poorly explored. We therefore aimed to investigate whether the Multidimensional Prognostic Index (MPI), an established tool that assesses measures of frailty and predicts mortality, may help physicians in identifying patients in whom ETF (enteral tube feeding) is effective in terms of reduced mortality. METHODS: Observational, longitudinal, multicenter study with one year of follow-up. Data regarding ETF were recorded through medical records. A standardized comprehensive geriatric assessment was used to calculate the MPI. Participants were divided in low (MPI-1), moderate (MPI-2) or severe (MPI-3) risk of mortality. Data regarding mortality were recorded through administrative information. RESULTS: 1064 patients were included, with 79 (13 in MPI 1-2 and 66 in MPI-3 class) receiving ETF. In multivariable analysis, patients receiving ETF experienced a higher risk of death (odds ratio, OR = 2.00; 95% confidence intervals, CI: 1.19-3.38). However, after stratifying for their MPI at admission, mortality was higher in MPI-3 class patients (OR = 2.03; 95%CI: 1.09-3.76), but not in MPI 1-2 class patients (OR = 1.51; 95%CI: 0.44-5.25). The use of propensity score confirmed these findings. CONCLUSIONS: ETF is associated with a higher risk of death. However, this is limited to more frail patients, suggesting the importance of the MPI in the prognostic evaluation of ETF.
- Keywords
- Enteral nutrition, Hospital, Multidimensional prognostic index, Prognosis,
- MeSH
- Enteral Nutrition * MeSH
- Inpatients * MeSH
- Humans MeSH
- Longitudinal Studies MeSH
- Mortality * MeSH
- Odds Ratio MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Australia MeSH
- Europe MeSH
MPI_AGE is a European Union co-funded research project aimed to use the Multidimensional Prognostic Index (MPI), a validated Comprehensive Geriatric Assessment (CGA)-based prognostic tool, to develop predictive rules that guide clinical and management decisions in older people in different European countries. A series of international studies performed in different settings have shown that the MPI is useful to predict mortality and risk of hospitalization in community-dwelling older subjects at population level. Furthermore, studies performed in older people who underwent a CGA before admission to a nursing home or receiving homecare services showed that the MPI successfully identified groups of persons who could benefit, in terms of reduced mortality, of specific therapies such as statins in diabetes mellitus and coronary artery disease, anticoagulants in atrial fibrillation and antidementia drugs in cognitive decline. A prospective trial carried out in nine hospitals in Europe and Australia demonstrated that the MPI was able to predict not only in-hospital and long-term mortality, but also institutionalization, re-hospitalization and receiving homecare services during the one-year follow-up after hospital discharge. The project also explored the association between MPI and mortality in hospitalized older patients in need of complex procedures such as transcatheter aortic valve implantation or enteral tube feeding. Evidence from these studies has prompted the MPI_AGE Investigators to formulate recommendations for healthcare providers, policy makers and the general population which may help to improve the cost-effectiveness of appropriate health care interventions for older patients.
- Keywords
- Comprehensive Geriatric Assessment, Frailty, MPI_AGE, Multidimensional Prognostic Index, Multimorbidity,
- MeSH
- Cost-Benefit Analysis MeSH
- Geriatric Assessment MeSH
- Hospitalization economics MeSH
- Frail Elderly * MeSH
- Humans MeSH
- Multimorbidity * MeSH
- Prognosis MeSH
- Prospective Studies MeSH
- Risk Factors MeSH
- Independent Living MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
