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1.
Diagnostics (Basel) ; 14(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38928646

RESUMO

A pre-transfusion crossmatch test is crucial for ensuring safe blood transfusions by identifying the compatibility between donor and recipient blood samples. Conventional tube methods for crossmatching have limitations, including subjectivity in result interpretation and the potential for human error. In this study, we evaluated the diagnostic performance of a new crossmatch test using Microscanner C3, which can overcome these shortcomings. The crossmatch test results using the method were obtained in 323 clinical samples. The sensitivity, specificity, positive predictive value, negative predictive value, and concordance rate of the crossmatch test using Microscanner C3 were 98.20%, 100.00%, 100.00%, 98.11%, and 99.07%, respectively. The diagnostic performance of the new system offers a promising alternative to conventional tube methods for pre-transfusion crossmatch testing. Microscanner C3 could also increase the automation, standardization, and accuracy of crossmatch tests. The crossmatch test using Microscanner C3 is thought to increase the efficiency and reliability in identifying blood samples suitable for transfusion, thereby improving patient safety and optimizing the use of blood products in clinical settings.

2.
Diagnostics (Basel) ; 14(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38201382

RESUMO

Counting CD4+ T lymphocytes using flow cytometry is a standard method for monitoring patients with HIV infections. Simpler and cheaper alternatives to flow cytometry are in high demand because getting access to flow cytometers is difficult or impossible in resource-limited settings. We evaluated the performance of the Microscanner Plus, a simple and automated image-based cell counter, in determining CD4 counts against a flow cytometer. CD4 count results of the Microscanner Plus and flow cytometer were compared using samples from 47 HIV-infected patients and 87 healthy individuals. All CV% for precision and reproducibility tests were less than 10%. The Microscanner Plus's lowest detectable CD4 count was determined to be 15.27 cells/µL of whole blood samples. The correlation coefficient (R) between Microscanner Plus and flow cytometry for CD4 counting in 134 clinical samples was very high, at 0.9906 (p < 0.0001). The automated Microscanner Plus showed acceptable analytical performance for counting CD4+ T lymphocytes and may be particularly useful for monitoring HIV patients in resource-limited settings.

3.
Micromachines (Basel) ; 13(4)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35457927

RESUMO

Piezoelectric micromirrors with aluminum nitride (AlN) and aluminum scandium nitride (Al0.68Sc0.32N) are presented and compared regarding their static deflection. Two chip designs with 2 × 3 mm2 (Design 1) and 4 × 6 mm2 (Design 2) footprint with 600 nm AlN or 2000 nm Al0.68Sc0.32N as piezoelectric transducer material are investigated. The chip with Design 1 and Al0.68Sc0.32N has a resonance frequency of 1.8 kHz and a static scan angle of 38.4° at 400 V DC was measured. Design 2 has its resonance at 2.1 kHz. The maximum static scan angle is 55.6° at 220 V DC, which is the maximum deflection measurable with the experimental setup. The static deflection per electric field is increased by a factor of 10, due to the optimization of the design and the research and development of high-performance piezoelectric transducer materials with large piezoelectric coefficient and high electrical breakthrough voltage.

4.
Sensors (Basel) ; 20(22)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218078

RESUMO

A 2D scanning micromirror with piezoelectric thin film aluminum nitride (AlN), separately used as actuator and sensor material, is presented. For endoscopic applications, such as fluorescence microscopy, the devices have a mirror plate diameter of 0.7 mm with a 4 mm2 chip footprint. After an initial design optimization procedure, two micromirror designs were realized. Different spring parameters for x- and y-tilt were chosen to generate spiral (Design 1) or Lissajous (Design 2) scan patterns. An additional layout, with integrated tilt angle sensors, was introduced (Design 1-S) to enable a closed-loop control. The micromirror devices were monolithically fabricated in 150 mm silicon-on-insulator (SOI) technology. Si (111) was used as the device silicon layer to support a high C-axis oriented growth of AlN. The fabricated micromirror devices were characterized in terms of their scanning and sensor characteristics in air. A scan angle of 91.2° was reached for Design 1 at 13 834 Hz and 50 V. For Design 2 a scan angle of 92.4° at 12 060 Hz, and 123.9° at 13 145 Hz, was reached at 50 V for the x- and y-axis, respectively. The desired 2D scan patterns were successfully generated. A sensor angle sensitivity of 1.9 pC/° was achieved.

5.
Res Vet Sci ; 133: 226-231, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33032109

RESUMO

As bone healing is altered after external radiation therapy, its evaluation is mandatory and lacks in clinical practice. The aim of the pilot study was to validate micro computed tomography (microCT) as a simple and reliable technique for assessing irradiated bone healing in the rabbit's mandible and compare with histologic findings. Nineteen rabbits (female New Zealand white) were used. The radiation protocol consisted of 5 sessions delivering 8.5 Gy each. MicroCT was performed at D0, D7, D14, D28 and D42 for the control group and D0, D28 and D42 for the irradiated group. A modified Perry's score was determined on histologic samples, and comparison between microCT and histological findings was performed. The main differences between irradiated and non-irradiated rabbits were observed at Day 28 and 42. There was a strong correlation between imaging and histologic findings. Radiation decreases bone quality and bone mineral density. As the correlation was strong between microCT and histologic findings, micro imaging could be considered as a simple and reliable technique to assess bone healing after radiation therapy and allows an easy comparison between samples, without invasive procedures. Great attention should be kept on the parameters and on the region of interest. The development of in-vivo microCT enlarges the perspectives of microCT use in experimental studies, avoiding invasive procedures, and preserving animal lives and well-being, and furthermore lead to clinical applications.


Assuntos
Doenças Ósseas/veterinária , Mandíbula/efeitos da radiação , Cicatrização , Microtomografia por Raio-X , Animais , Densidade Óssea/efeitos da radiação , Feminino , Mandíbula/cirurgia , Projetos Piloto , Coelhos , Radioterapia/veterinária , Microtomografia por Raio-X/métodos
6.
Micromachines (Basel) ; 10(4)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934767

RESUMO

This paper describes an input shaping method based on an experimental transfer function to effectively obtain a desired scan output for an electrostatic microscanner driven in a quasistatic mode. This method features possible driving extended to a higher frequency, whereas the conventional control needs dynamic modeling and is still ineffective in mitigating harmonics, sub-resonances, and/or higher modes. The performance of the input shaping was experimentally evaluated in terms of the usable scan range (USR), and its application limits were examined with respect to the optical scan angle and frequency. The experimental results showed that the usable scan range is as wide as 96% for a total optical scan angle (total OSA) of up to 9° when the criterion for scan line error is 1.5%. The usable scan ranges were degraded for larger total optical scan angles because of the nonlinear electrostatic torque with respect to the driving voltage. The usable scan range was 90% or higher for most frequencies up to 160 Hz and was drastically decreased for the higher driving frequency because fewer harmonics are included in the input shaping process. Conclusively, the proposed method was experimentally confirmed to show good performance in view of its simplicity and its operable range, quantitatively compared with that of the conventional control.

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