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1.
Chin Med ; 19(1): 85, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877519

RESUMO

BACKGROUND: Liguzinediol (Lig) has emerged as a promising candidate for mitigating Doxorubicin (DOX)-induced cardiotoxicity, a significant limitation in the clinical application of this widely used antineoplastic drug known for its efficacy. This study aimed to explore the effects and potential mechanisms underlying Lig's protective role against DOX-induced cardiotoxicity. METHODS: C57BL/6 mice were treated with DOX. Cardiac function changes were observed by echocardiography. Cardiac structure changes were observed by HE and Masson staining. Immunofluorescence was applied to visualize the cardiomyocyte apoptosis. Western blotting was used to detect the expression levels of AMP-activated protein kinase (AMPK), sirtuin 3 (SIRT3), Caspase-3 and gasdermin E N-terminal fragment (GSDME-N). These experiments confirmed that Lig had an ameliorative effect on DOX-induced cardiotoxicity in mice. RESULTS: The results demonstrated that Lig effectively countered myocardial oxidative stress by modulating intracellular levels of reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD). Lig reduced levels of creatine kinase (CK) and lactate dehydrogenase (LDH), while ameliorating histopathological changes and improving electrocardiogram profiles in vivo. Furthermore, the study revealed that Lig activated the AMPK/SIRT3 pathway, thereby enhancing mitochondrial function and attenuating myocardial cell apoptosis. In experiments with H9C2 cells treated with DOX, co-administration of the AMPK inhibitor compound C (CC) led to a significant increase in intracellular ROS levels. Lig intervention reversed these effects, along with the downregulation of GSDME-N, interleukin-1ß (IL-1ß), and interleukin-6 (IL-6), suggesting a potential role of Lig in mitigating Caspase-3/GSDME-mediated pyroptosis. CONCLUSION: The findings of this study suggest that Lig effectively alleviates DOX-induced cardiotoxicity through the activation of the AMPK/SIRT3 pathway, thereby presenting itself as a natural product with therapeutic potential for preventing DOX-associated cardiotoxicity. This novel approach may pave the way for the development of alternative strategies in the clinical management of DOX-induced cardiac complications.

2.
Small ; : e2400466, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38676346

RESUMO

The efficient removal of droplets on solid surfaces holds significant importance in the field of fog collection, condensation heat transfer, and so on. However, on current typical surfaces, droplets are characterized by a passive and single removal mode, contingent on the traction force (e.g., capillary force, Laplace pressure, etc.) generated by the surface's physics and chemistry design, posing challenges for enhancing the efficiency of droplet removal. In this paper, an effective active strategy based on different removal modes is demonstrated on magnetic responsive polydimethylsiloxane (PDMS) superhydrophobic microplates (RM-MPSM). By regulating the parameters of microplates and droplet volume, different effective departure modes (top jumping and side departure) can be induced to facilitate the removal of droplets. Moreover, the removal volume of droplets through the side departure mode exhibits a significant reduction compared to that observed in the top jumping mode. The exceptional removal ability of RM-MPSM demonstrates adaptability to diverse functional applications: efficient fog collection, removal of condensation droplets and micro-particles. The efficient modes of droplet removal demonstrated in this work hold significant implications for broadening its application in many fields, such as droplet collection, heat transfer, and anti-icing.

3.
J Colloid Interface Sci ; 662: 563-571, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38367574

RESUMO

Efficient removal of droplets from solid surfaces is significant in various fields, including fog collection and condensation heat transfer. However, droplets removal on common surfaces with static structures often occurs passively, which limits the possibility of increasing removal efficiency and lacks intelligent controllability. In this paper, an active strategy based on extrusion ejection is proposed and demonstrated on the magnetic responsive polydimethylsiloxane (PDMS) superhydrophobic microplates (MPSM). The MPSM can reversibly transit between the upright and tilted state as the external magnetic field is alternately applied and removed. Under the magnetic field, the direction and trajectories of droplets departure can be intelligently controlled, demonstrating excellent controllability. More importantly, compared with the static structure where the droplet must reach a certain size before departure, droplets can be ejected at smaller sizes as the MPSM is tilted. These advantages are of great significance in many fields, such as a highly efficient fog harvesting system. This strategy of extrusion ejection based on dynamic surface structure control reported in this work may provide fresh ideas for efficient droplet manipulation.

4.
Front Cardiovasc Med ; 10: 1183787, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745096

RESUMO

Pregnancy predisposes to arrhythmias in females due to physiological changes in the cardiovascular system, enhanced activity of the sympathetic nervous system (SNS), and changes in the endocrine system, regardless of whether there exist cardiovascular diseases before the pregnancy. Tachyarrhythmias may present for the first time or worsen persistently during pregnancy, potentially leading to maternal heart failure and sudden death, as well as some adverse fetal outcomes such as growth restriction, distress, premature birth, and stillbirth. Radiofrequency ablation (RFA) is one of the most important therapeutic methods for tachyarrhythmias. According to the 2019 European Society of Cardiology (ESC) guidelines, RFA in pregnant women should preferably be performed without x-rays. Since the 2000s, 3D mapping technique has rapidly developed, laying the foundation for cardiac electrophysiology examination free from x-rays. Ventricular arrhythmia originating from the left coronary cusp (LCC) is not common in clinic. RFA is challenging in the treatment of this type of disease due to the anatomical feature that the opening of the left main coronary artery is localized in the LCC.

5.
ACS Omega ; 8(34): 31365-31372, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37663457

RESUMO

In seasonally frozen regions, the bearing capacity of soil decreases and gradually deteriorates after undergoing freeze-thaw cycles. To resolve this problem, based on the idea of frost-resistant filling materials, a filling scheme of expanded polystyrene (EPS) particles lightweight soil in cold regions was proposed. Unconfined compressive strength, direct shear, and micro-SEM tests were carried out to study the physical and mechanical properties of EPS particles lightweight soil under freeze-thaw cycles. The results indicate that the EPS particle lightweight soil has good frost resistance and can be used as frost-resistant filling material in cold regions. Under freeze-thaw cycles, EPS particle lightweight soil maintains good integrity; EPS particles can effectively reduce the frost heave rate, mass loss rate, and compressive strength loss rate of lightweight soil. The compressive strength depends on the EPS and cement contents: it decreases with an increase in the EPS content and increases with an increase in the cement content. The strength loss rate decreases with an increase in both. When the content of EPS is larger (more than 2%), the soil cement bound with EPS particles is limited, and the performance of lightweight soil decreases. The shear strength and cohesion decrease with an increase in freeze-thaw cycles and EPS content, and the internal friction angle follows no obvious rule with regard to the increase in freeze-thaw cycles but decreases with an increase in the EPS content. Based on the experimental results, an empirical formula for the compressive strength of EPS particle lightweight soil under freeze-thaw cycles was proposed. This study can provide a reference for the engineering design and application and provide new ideas for resolving freeze-thaw problems in construction engineering in cold regions.

6.
J Cardiothorac Surg ; 18(1): 242, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37559141

RESUMO

BACKGROUND: The choice of anastomosis technique after esophagectomy is closely associated with the postoperative complications. Whether circular stapled or linear stapled anastomosis is the optimal technique has not been established. Therefore, we conducted this meta-analysis to show the latest and most comprehensive published assessment of circular stapled anastomosis in comparison with linear stapled anastomosis in postoperative complications. METHODS: Databases (PubMed, Embase, Web of science, Cochrane Library) were searched for all randomized controlled trials and comparative studies comparing circular stapled anastomosis with linear stapled anastomosis after esophagectomy. The odd ratio and mean difference with 95% confidence interval were calculated. We used the Higgins I² statistics to assess the statistical heterogeneity between studies. Review manager (version 5.4) software was used in this analysis. RESULTS: Sixteen studies with 2322 patients were included in our study. The study demonstrated that the use of linear stapled technique after esophagectomy could reduce the risk of both anastomotic leakage (P = 0.0003) and stricture (P < 0.00001) compared with circular stapled technique. Stratification by anastomotic site showed that no matter what kind of anastomotic site (cervical or thoracic anastomosis) was used, linear stapled anastomosis could effectively reduce the anastomotic stricture in comparison with circular stapled anastomosis. Moreover, linear stapled anastomosis could decrease the risk of thoracic anastomotic leakage. There were no significant differences between circle stapled anastomosis and linear stapled anastomosis in reflux esophagitis (P = 0.17), pneumonia (P = 0.91), operation time (P = 0.41) and hospital stay (P = 0.38). CONCLUSIONS: The study suggested that linear stapled anastomosis could be considered to be an optimal treatment associated with a reduced risk of anastomotic leakage and stricture in comparison with circular stapled anastomosis.


Assuntos
Neoplasias Esofágicas , Esofagectomia , Humanos , Esofagectomia/efeitos adversos , Esofagectomia/métodos , Fístula Anastomótica/prevenção & controle , Fístula Anastomótica/etiologia , Técnicas de Sutura/efeitos adversos , Grampeamento Cirúrgico , Constrição Patológica/cirurgia , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/complicações , Resultado do Tratamento , Anastomose Cirúrgica/métodos , Complicações Pós-Operatórias/etiologia
7.
Microsyst Nanoeng ; 9: 48, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37077933

RESUMO

High-precision microelectromechanical system (MEMS) gyroscopes are significant in many applications. Bias instability (BI) is an important parameter that indicates the performance of a MEMS gyroscope and is affected by the 1/f noise of the MEMS resonator and readout circuit. Since the bandgap reference (BGR) is an important block in the readout circuit, reducing its 1/f noise is key to improving a gyroscope's BI. In a traditional BGR, the error amplifier is applied to provide a virtual short-circuit point, but it introduces the main low-frequency noise sources. This paper proposes an ultralow 1/f noise BGR by removing the error amplifier and applying an optimized circuit topology. In addition, a simplified but accurate noise model of the proposed BGR is obtained to optimize the BGR's output noise performance. To verify this design, the proposed BGR has been implemented in a 180 nm CMOS process with a chip area of 545 × 423 µm. The experimental results show that the BGR's output integrated noise from 0.1 to 10 Hz is 0.82 µV and the thermal noise is 35 nV/√Hz. Furthermore, bias stability tests of the MEMS gyroscope fabricated in our laboratory with the proposed BGR and some commercial BGRs are carried out. Statistical results show that reducing the BGR's 1/f noise can nearly linearly improve the gyroscope's BI.

8.
Mater Horiz ; 10(7): 2464-2475, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37039134

RESUMO

Complex and controlled reversible actuation inevitably relies on changing thermal fields (direct or indirect) for semi-crystalline reversible shape memory networks. Unfortunately, the non-tunability of thermal signals often brings potential limitations to actuators' applications. In practice, a wide response temperature range (T-range) formed by Thigh and Tlow in the remarkable reversible actuation is an obvious fact. Herein, we demonstrate the tunability of the transition temperatures while stably maintaining excellent actuation abilities. We further verified that the narrow T-range (24 °C) that had not been reported could present more than 17% reversible strain. Special parameter optimization provides opportunities for potential non-implantable biomedical applications. Therefore, based on target 2W-SMP, a vehicle concept with the drug release and vehicle recovery ability was proposed, proving our approach's feasibility.

9.
Fa Yi Xue Za Zhi ; 38(4): 526-532, 2022 Aug 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36426699

RESUMO

The oral cavity is the second largest microbial bank in humans after the intestinal canal, colonizing a large number of microorganisms including viruses, bacteria, archaea, fungi and protozoa. The great number of microbial cells, good DNA stability, and individual has a unique microbial community, these characteristics make the human microbiome expected to become a new biomarker for forensic individual identification. This article describes the characteristics of human oral microorganisms and microbial molecular markers in detail, analyzes the potential application value of microorganisms in forensic individual identification, and reviews the research progress of human oral microorganisms in forensic individual identification.


Assuntos
Microbiota , Humanos , Medicina Legal
11.
Kidney360 ; 3(6): 1047-1056, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35845326

RESUMO

Background: Recent investigations have shown that, on average, patients hospitalized with coronavirus disease 2019 (COVID-19) have a poorer postdischarge prognosis than those hospitalized without COVID-19, but this effect remains unclear among patients with end-stage kidney disease (ESKD) who are on dialysis. Methods: Leveraging a national ESKD patient claims database administered by the US Centers for Medicare and Medicaid Services, we conducted a retrospective cohort study that characterized the effects of in-hospital COVID-19 on all-cause unplanned readmission and death within 30 days of discharge for patients on dialysis. Included in this study were 436,745 live acute-care hospital discharges of 222,154 Medicare beneficiaries on dialysis from 7871 Medicare-certified dialysis facilities between January 1 and October 31, 2020. Adjusting for patient demographics, clinical characteristics, and prevalent comorbidities, we fit facility-stratified Cox cause-specific hazard models with two interval-specific (1-7 and 8-30 days after hospital discharge) effects of in-hospital COVID-19 and effects of prehospitalization COVID-19. Results: The hazard ratios due to in-hospital COVID-19 over the first 7 days after discharge were 95% CI, 1.53 to 1.65 for readmission and 95% CI, 1.38 to 1.70 for death, both with P<0.001. For the remaining 23 days, the hazard ratios were 95% CI, 0.89 to 0.96 and 95% CI, 0.86 to 1.07, with P<0.001 and P=0.50, respectively. Effects of prehospitalization COVID-19 were mostly nonsignificant. Conclusions: In-hospital COVID-19 had an adverse effect on both postdischarge readmission and death over the first week. With the surviving patients having COVID-19 substantially selected from those hospitalized, in-hospital COVID-19 was associated with lower rates of readmission and death starting from the second week.


Assuntos
COVID-19 , Falência Renal Crônica , Assistência ao Convalescente , Idoso , COVID-19/epidemiologia , Humanos , Falência Renal Crônica/epidemiologia , Medicare , Alta do Paciente , Diálise Renal , Estudos Retrospectivos , Estados Unidos/epidemiologia
12.
Front Microbiol ; 13: 777882, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369525

RESUMO

The human microbiome has emerged as a new potential biomarker for forensic investigations with the development of high-throughput sequencing and bioinformatic analysis during the last decade. The oral cavity has many different microbial habitats, with each habit colonized by specific and individualized microbiota. As saliva and buccal mucosa are common biological evidence in forensic science, understanding the differences of microbial communities between the two is important for forensic original identification. Moreover, the oral microbiota is individualized, whereas there are few studies on the application of forensic personal identification that need to be supplemented. In this study, Streptococcus was the most abundant genus, with an average relative abundance of 49.61% in the buccal mucosa, while in the saliva, Streptococcus, Veillonella, and Neisseria had similar proportions (20%, 15%, 16%) and were the dominant genera. The α and ß diversity displayed a significant distinctness between the saliva and buccal mucosal groups. The community assembly mechanism stated that the deterministic process played a more significant effect in shaping the salivary bacterial community assembly than buccal mucosa, which explained the microbial differences. Of the test samples, 93.3% can be correctly classified with the random forest model based on the microbial differences. Targeting the low-abundance bacteria at the species level, 52% of experimental participants could be discriminated by using the observed unique bacterial species. In conclusion, the salivary bacterial community composition differed from that of the buccal mucosa and showed high richness and diversity. With the random forest model, the microbiota of saliva and buccal mucosa can be classified, which can be used in identifying the source of oral biological trace. Furthermore, each individual has a unique bacterial community pattern, and the presence or absence of unique bacteria and differences in the composition of the core oral microbiota are the key points for forensic personal discrimination that supplement the study of oral microbial application to forensic personal discrimination. Whether for original identification or personal discrimination, the oral microbiome has great potential for application.

13.
Microb Cell Fact ; 21(1): 46, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35331204

RESUMO

BACKGROUND: Human gut microbiota is individually unique that hints the microbiota in fecal traces left in the crime scene could act as a potential biomarker for forensic personal identification. Next-generation DNA sequencing and bioinformatic analysis of fecal samples are revolutionizing our insights into gut microbial communities. While the formation of the gut microbiota is known to be multifactorial, it is unclear whether these characteristics can be applied to forensic applications. Therefore, the gut microbiota of healthy adults with different traits was investigated in this study. RESULTS: Based on the STAMP analysis of each study group, the difference in gut microbiota composition of male and female subjects was observed. The male group was characterized by taxa in the phylum Proteobacteria, while the female group was described by Synergistetes phylum. The gut bacterial community assembly mechanism was mainly affected by the deterministic process. In addition, gut microbiota composition showed meaningful discrimination in each of the BMI groups. At the phylum level, in male subjects, increased representative phyla were Patescibacteria (p < 0.05) in the underweight group and Bacteroidetes (p < 0.05) in the normal-weight group, while in the female group, the significantly different phyla were Bacteroidetes, Firmicutes, and Actinobacteria. At the genus level, 44 unique genera were found to be significantly distinct across BMI study groups. By Fisher's Linear Discriminant Analysis, ninety-four point four percent (94.4%) of original BMI grouped subjects were correctly classified. The linear regression analysis model showed an accuracy of seventy-four percent (74%) in predicting body type. CONCLUSION: In conclusion, subjects with different individual characters have specific gut microbiota, and can be discriminated by bioinformatics methods, suggesting it is promising to apply gut microbiota to forensic personal identification.


Assuntos
Microbioma Gastrointestinal , Microbiota , Adulto , Bactérias/genética , Fezes/microbiologia , Feminino , Firmicutes , Microbioma Gastrointestinal/genética , Humanos , Masculino
14.
Langenbecks Arch Surg ; 407(4): 1517-1524, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35306600

RESUMO

PURPOSE: Pancreatic surgery is a complex operation that has been associated with severe intraoperative and postoperative complications, especially in patients with previous abdominal surgery (PAS). Our study aimed to assess the impact of PAS on pancreatic surgery. METHODS: A total of 1430 patients who underwent pancreatic surgery were included in this retrospective study and classified into the following 3 groups: previous upper abdominal surgery (PUAS) (n = 135); previous lower abdominal surgery (PLAS) (n = 161), and no history of abdominal surgery (non-PAS) (n = 1134). Using propensity score matching (PSM), patients were matched to one another at a 1:1:1 ratio with balanced baseline characteristics. Intraoperative factors, surgical complications, hospital costs, and postoperative hospitalization were collected and compared. RESULTS: A longer operative duration was observed in the PUAS group compared to the non-PAS group (187.54 vs. 150.50 min, p = 0.016). The intraoperative blood loss in the PUAS group was significantly higher (193.68 vs. 150.51 and 156.81 mL, p < 0.05), while the intraoperative plasma transfusion volume was higher in PLAS patients than in non-PAS patients (183.8 vs. 102.7 mL, p = 0.008). Intra-abdominal adhesions in PUAS patients were most severe, and non-PAS patients exhibited significantly lower intra-abdominal adhesion grading (p < 0.001). No significant differences were observed in postoperative complications, postoperative histopathology, postoperative hospitalization, or hospital cost. CONCLUSION: PAS has no significant influences on surgical outcomes, and pancreatic surgery is relatively safe in this patient population. A patient history of PAS may prolong operation duration and increase intraoperative blood loss but has no impact on postoperative complications and does not increase the economic burden.


Assuntos
Laparoscopia , Transfusão de Componentes Sanguíneos , Perda Sanguínea Cirúrgica , Humanos , Plasma , Complicações Pós-Operatórias/epidemiologia , Pontuação de Propensão , Estudos Retrospectivos , Resultado do Tratamento
15.
Forensic Sci Int ; 324: 110849, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34030000

RESUMO

With the widespread use of STR in identification of individuals, paternity testing, as well as population genetics, many commercially robust and validated STR multiplex kits were developed. The AGCU Expressmarker 30 Kit is a new autosomal STR system that contains 29 autosomal STR loci (D3S1358, vWA, D1S1656, CSF1PO, D8S1132, D19S253, D3S3045, D8S1179, D21S11, D16S539, TPOX, D6S477, Penta D, D2S441, D5S818, TH01, FGA, D15S659, D22S1045, D19S433, D13S317, D7S820, D6S1043, D10S1435, D10S1248, D2S1338, D18S51, D12S391, and Penta E), one insertion/deletion polymorphic marker on the Y chromosome (Y indel), and the amelogenin locus. A series of validation studies were performed in this context according to the guidelines of "Validation Guidelines for Forensic DNA Analysis Methods". The sensitivity study showed that a full profile was observed with template DNA as low as 40 pg. In the stability study, all STR profiles were obtained at concentrations of humic acid up to 800 ng/µL, hematin up to 250 µM, and tannic acid up to 200 ng/µL. The mixture study demonstrated that all of the minor alleles could be called at ratios from 1:1-29:1 when the total DNA was 2 ng. In the population study, the total discrimination power for three population (Sichuan-Han, Gansu-Hui, and Guangxi-Zhuang) were above 0.9999999999999999999999999999999992, 0.999999999999999999999999999999998 and 0.999999999999999999999999999999994 as well as the cumulative probability of paternity exclusion were 0.999999999999953, 0.999999999999178, and 0.999999999999611 respectively. These results demonstrated that the AGCU Expressmarker 30 Kit is a useful tool for analyzing both forensic casework and database samples.


Assuntos
Impressões Digitais de DNA/instrumentação , Genética Forense/instrumentação , Repetições de Microssatélites , Animais , Etnicidade/genética , Humanos , Reação em Cadeia da Polimerase , Especificidade da Espécie
16.
ACS Omega ; 5(33): 21067-21075, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32875243

RESUMO

In this work, to make out the aryl-fusion effect on the photophysical properties of boron-pyridyl-imino-isoindoline dyes, compounds 1-5 were theoretically studied through analyses of their geometric and electronic structures, optical properties, transport abilities, and radiative (k r) and non-radiative decay rate (k nr) constants. The highest occupied molecular orbitals of aryl-fused compounds 2-5 are higher owing to the extended conjugation. Interestingly, aryl fusion in pyridyl increases the lowest unoccupied molecular orbital (LUMO) level, while isoindoline decreases the LUMO level; thus, 4 and 5 with aryl fusion both in pyridyl and isoindoline exhibit a similar LUMO to 1. Compounds 4 and 5 show relatively low ionization potentials and high electron affinities, suggesting a better ability to inject holes and electrons. Importantly, the aryl fusion is conducive to the decrease of k IC. The designed compound 5 exhibits a red-shifted emission maximum, low λh, and low k IC, which endow it with great potential for applications in organic electronics. Our investigation provides an in-depth understanding of the aryl-fusion effect on boron-pyridyl-imino-isoindoline dyes at molecular levels and demonstrates that it is achievable.

17.
Micromachines (Basel) ; 11(1)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936635

RESUMO

This paper presents a novel multi-objective parameter optimization method based on the genetic algorithm (GA) and adaptive moment estimation (Adam) algorithm for the design of a closed-loop control system for the sense mode of a Microelectromechanical systems (MEMS) gyroscope. The proposed method can improve the immunity of the control system to fabrication tolerances and external noise. The design procedure starts by deriving a parameterized model of the closed-loop of the sense mode. The loop parameters are then optimized by the GA. Finally, the ensemble of optimized loop parameters is tested by Monte Carlo analysis to obtain a robust optimal solution. Simultaneously, the Adam-least mean square (LMS) demodulator, which is appropriate for the demodulation of very noisy signals, is also presented. Compared with the traditional method, the time consumption of the design process is reduced significantly. The digital control system is implemented by the print circuit board based on embedded Field Programmable Gate Array (FPGA). The experimental results show that the optimized control loop has achieved a better performance, the system bandwidth in open-loop and optimal closed-loop control system is about 23 Hz and 101 Hz, respectively. Compared to a non-optimized closed-loop system, the bias instability reduced from 0.0015°/s to 7.52 × 10-4°/s, the scale factor increased from 17.7 mV/(°/s) to 23 mV/(°/s) and the non-linearity of the scale factor reduced from 0.008452% to 0.006156%.

19.
Micromachines (Basel) ; 10(12)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783623

RESUMO

This paper presents a bias drift self-calibration method for micro-electromechanical systems (MEMS) gyroscopes based on noise-suppressed mode reversal without the modeling of bias drift signal. At first, the bias drift cancellation is accomplished by periodic switching between operation mode of two collinear gyroscopes and subtracting the bias error which is estimated by the rate outputs from a consecutive period interval; then a novel filtering algorithm based on improved complete ensemble empirical mode decomposition (improved complete ensemble empirical mode decomposition with adaptive noise-CEEMDAN) is applied to eliminate the noise in the calibrated signal. A set of intrinsic mode functions (IMFs) is obtained by the decomposition of the calibrated signal using improved CEEMDAN method, and the threshold denoising method is utilized; finally, the de-noised IMFs are reconstructed into the desired signal. To verify the proposed method, the hardware circuit with an embedded field-programmable gate array (FPGA) was implemented and applied in bias drift calibration for the two MEMS gyroscopes manufactured in our laboratory. The experimental results indicate that the proposed method is feasible, and it achieved a better performance than the typical mode reversal. The bias instability of the two gyroscopes decreased from 0.0066 ° / s and 0.0055 ° / s to 0.0011 ° / s ; and, benefiting from the threshold denoising based on improved CEEMDAN, the angle random walks decreased from 1.18 × 10 - 4 ° / s 1 / 2 and 2.04 × 10 - 4 ° / s 1 / 2 to 2.19 × 10 - 5 ° / s 1 / 2 , respectively.

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