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1.
Plast Reconstr Surg Glob Open ; 12(4): e5702, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38596591

RESUMEN

Virtual surgical planning (VSP) and three-dimensional (3D) printing can increase precision and reduce surgical time in craniofacial reconstruction. However, the elevated cost and manufacturing time of outsourced workflows is increasing the development of in-house solutions. One of the main challenges in in-house workflows is to create cutting guides that hold plate position information. This is due to the fact that hospitals usually lack the infrastructure required to design and 3D print custom-made plates. Including plate-positioning information in resection guides is especially relevant in complex reconstructions and when tumor extension limits plate placement before resection. Current in-house workflows revolve around the idea of 3D scanning the bent plate's shape and to fuse it with the VSP. The goal of this article is to share our technique to transfer plate position information to resection guides. Our protocol uses a 3D model of the reconstruction as an intermediate step to transfer the plate position of a bent stock reconstruction plate to cutting guides. Two patients who required mandibular reconstruction with fibula flap are presented to illustrate the technique. This workflow requires a 3D-printed model of the desired outcome, cutting guides, and a stock plate. Results were satisfactory in terms of cutting location and angulation, plate adaptation and condylar position. This technique allows for a simple, safe, cheap, and quick alternative to add reconstruction plate information to cutting guides.

2.
AJOG Glob Rep ; 4(1): 100325, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38586615

RESUMEN

BACKGROUND: Fetal cardiology has shown a rapid development in the past decades. Fetal echocardiography is not only used for the detection of structural anomalies but also to assess fetal cardiac function. Assessment of the fetal cardiac function is performed mostly in the second and third trimesters. The study of fetal cardiac function at the end of first trimester has not been investigated properly, and there is a lack of reference values at early gestational weeks. OBJECTIVE: This study aimed to assess if the measurement of time-related parameters of cardiac function in the left ventricle of the fetal heart is feasible and reproducible at the end of the first trimester. If possible, we provide nomograms of these parameters from 11 to 13+6 gestational weeks. STUDY DESIGN: We conducted a prospective observational study from March to September 2022. The study was carried out in 2 hospitals (Hospital Universitari Dexeus, Barcelona, and Hospital VITAHS 9 Octubre, Valencia, Spain). The scans were performed by 3 specialists in fetal medicine. The exclusion criteria were fetal cardiac rhythm abnormalities, abnormal nuchal translucency, abnormal ductus venosus, fetal malformations, stillbirth, estimated fetal weight <10 percentile, diabetes, and gestational hypertensive disorders. The cardiac function parameters studied in the left ventricle were isovolumetric contraction time, isovolumetric relaxation time, ejection time, filling time, cycle time, myocardial performance index, ejection time fraction, and filling time fraction. We study the feasibility and intra- and interobserver reproducibility of these parameters using the interclass correlation coefficient. Nomograms were created and the percentiles of the values of the different parameters were calculated. RESULTS: A total of 409 cases were recruited but only 296 could be included in the statistical analysis once the exclusion criteria were applied. The intraobserver reproducibility study was excellent (interclass correlation coefficient >0.900), and the interobserver reproducibility study was good (interclass correlation coefficient >0.700). The data regression analysis showed that cycle time, filling time, isovolumetric contraction time, and filling time fraction increased with gestational age, whereas ejection time fraction decreased with gestational age and myocardial performance index (mean, 0.43±0.08), isovolumetric relaxation time (mean, 0.04±0.01), and ejection time (mean, 0.16±0.01) remained constant from 11 to 13 weeks. CONCLUSION: The study of fetal cardiac function is feasible and reproducible at 11 to 13+6 gestational weeks. Nomograms of the studied parameters are provided.

3.
Hum Reprod ; 39(5): 1098-1104, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38498835

RESUMEN

STUDY QUESTION: Is there any difference in ovarian response and embryo ploidy following progesterone-primed ovarian stimulation (PPOS) using micronized progesterone or GnRH antagonist protocol? SUMMARY ANSWER: Pituitary downregulation with micronized progesterone as PPOS results in higher number of oocytes retrieved and a comparable number of euploid blastocysts to a GnRH antagonist protocol. WHAT IS KNOWN ALREADY: Although the GnRH antagonist is considered by most the gold standard protocol for controlling the LH surge during ovarian stimulation (OS) for IVF/ICSI, PPOS protocols are being increasingly used in freeze-all protocols. Still, despite the promising results of PPOS protocols, an early randomized trial reported potentially lower live births in recipients of oocytes resulting following downregulation with medroxyprogesterone acetate as compared with a GnRH antagonist protocol. The scope of the current prospective study was to investigate whether PPOS with micronized progesterone results in an equivalent yield of euploid blastocysts to a GnRH antagonist protocol. STUDY DESIGN, SIZE, DURATION: In this prospective study, performed between September 2019 to January 2022, 44 women underwent two consecutive OS protocols within a period of 6 months in a GnRH antagonist protocol or in a PPOS protocol with oral micronized progesterone. PARTICIPANTS/MATERIALS, SETTING, METHODS: Overall, 44 women underwent two OS cycles with an identical fixed dose of rFSH (225 or 300 IU) in both cycles. Downregulation in the first cycles was performed with the use of a flexible GnRH antagonist protocol (0.25 mg per day as soon as one follicle of 14 mm) and consecutively, after a washout period of 1 month, control of LH surge was performed with 200 mg of oral micronized progesterone from stimulation Day 1. After the completion of both cycles, all generated blastocysts underwent genetic analysis for aneuploidy screening (preimplantation genetic testing for aneuplody, PGT-A). MAIN RESULTS AND THE ROLE OF CHANCE: Comparisons between protocols did not reveal differences between the duration of OS. The hormonal profile on the day of trigger revealed statistically significant differences between protocols in all the tested hormones except for FSH: with significantly higher serum E2 levels, more elevated LH levels and higher progesterone levels in PPOS cycles as compared with antagonist cycles, respectively. Compared with the GnRH antagonist protocol, the PPOS protocol resulted in a significantly higher number of oocytes (12.7 ± 8.09 versus 10.3 ± 5.84; difference between means [DBM] -2.4 [95% CI -4.1 to -0.73]), metaphase II (9.1 ± 6.12 versus 7.3 ± 4.15; DBM -1.8 [95% CI -3.1 to -0.43]), and 2 pronuclei (7.1 ± 4.99 versus 5.7 ± 3.35; DBM -1.5 [95% CI -2.6.1 to -0.32]), respectively. Nevertheless, no differences were observed regarding the mean number of blastocysts between the PPOS and GnRH antagonist protocols (2.9 ± 2.11 versus 2.8 ± 2.12; DBM -0.07 [95% CI -0.67 to 0.53]) and the mean number of biopsied blastocysts (2.9 ± 2.16 versus 2.9 ± 2.15; DBM -0.07 [95% CI -0.70 to 0.56]), respectively. Concerning the euploidy rates per biopsied embryo, a 29% [95% CI 21.8-38.1%] and a 35% [95% CI 26.6-43.9%] were noticed in the PPOS and antagonist groups, respectively. Finally, no difference was observed for the primary outcome, with a mean number of euploid embryos of 0.86 ± 0.90 versus 1.00 ± 1.12 for the comparison of PPOS versus GnRh antagonist. LIMITATIONS, REASONS FOR CAUTION: The study was powered to detect differences in the mean number of euploid embryos and not in terms of pregnancy outcomes. Additionally, per protocol, there was no randomization, the first cycle was always a GnRH antagonist cycle and the second a PPOS with 1 month of washout period in between. WIDER IMPLICATIONS OF THE FINDINGS: In case of a freeze-all protocol, clinicians may safely consider oral micronized progesterone to control the LH surge and patients could benefit from the advantages of a medication of oral administration, with a potentially higher number of oocytes retrieved at a lower cost, without any compromise in embryo ploidy rates. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by an unrestricted grant from Theramex. N.P.P. has received Research grants from Merck Serono, Organon, Ferring Pharmaceutical, Roche, Theramex, IBSA, Gedeon Richter, and Besins Healthcare; honoraria for lectures from: Merck Serono, Organon, Ferring Pharmaceuticals, Besins International, Roche Diagnostics, IBSA, Theramex, and Gedeon Richter; consulting fees from Merck Serono, Organon, Besins Healthcare, and IBSA. M.d.M.V., F.M., and I.R. declared no conflicts of interest. TRIAL REGISTRATION NUMBER: The study was registered at Clinical Trials Gov. (NCT04108039).


Asunto(s)
Hormona Liberadora de Gonadotropina , Inducción de la Ovulación , Ploidias , Progesterona , Femenino , Humanos , Inducción de la Ovulación/métodos , Progesterona/administración & dosificación , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Adulto , Estudios Prospectivos , Embarazo , Antagonistas de Hormonas/administración & dosificación , Antagonistas de Hormonas/farmacología , Blastocisto/efectos de los fármacos , Índice de Embarazo , Recuperación del Oocito , Transferencia de Embrión/métodos , Administración Oral , Inyecciones de Esperma Intracitoplasmáticas/métodos
7.
Maturitas ; 180: 107873, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37995422

RESUMEN

OBJECTIVE: To study sociodemographic and clinical factors associated with the long-COVID-19 syndrome among women living in Latin American countries using undirected and directed methods. METHOD: We studied 347 patients with COVID-19 (confirmed by polymerase chain reaction) living in nine Latin American countries between May 2021 and July 2022, including 70 premenopausal, 48 perimenopausal, and 229 postmenopausal women. We compared the sociodemographic and general health information of women with (n = 164) and without (n = 183) the long-COVID-19 syndrome. They also completed the Connor-Davidson Resilience Scale, the Fear of COVID-19 Scale, the Jenkins Sleep Scale, and the Menopause Rating Scale to define the minimum set of variables for adjustment. We designed a directed acyclic graph (DAG) to identify factors related to the long-COVID-19 syndrome. Data were submitted to categorical logistic regression analyses. Results are reported as means and standard deviations or ß-coefficients and 95 % confidence intervals. RESULTS: Women with long-COVID-19 syndrome had a poor lifestyle, severe menopause symptoms, hypertension, insomnia, depression, anxiety, chronic diseases/conditions, risk of hospitalization, sleep disturbance, and low menopause-related quality of life compared to women without the syndrome. The DAG identified the following long-COVID-19 covariates: age, obesity, anxiety, depression, cancer, lifestyle, smoking, and menstrual status. A multivariable logistic model with these covariates indicated that anxiety is the only factor to be significantly associated with long-COVID-19 syndrome, whereas other covariates were confounding factors. There was no significant influence of menopausal status on the long-COVID-19 syndrome. CONCLUSION: Among factors selected by the DAG, only anxiety was significantly associated with the long-COVID-19. There was no significant influence of the menopause status on the long-COVID-19 syndrome in the studied population.


Asunto(s)
COVID-19 , Pruebas Psicológicas , Calidad de Vida , Femenino , Humanos , América Latina/epidemiología , Síndrome Post Agudo de COVID-19 , Depresión/epidemiología , Depresión/complicaciones , COVID-19/epidemiología , Menopausia , Ansiedad/epidemiología , Resiliencia Psicológica
9.
J Clin Med ; 12(18)2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37762998

RESUMEN

(1) Background: The presence of adenomyosis among pregnant patients has been associated with a higher incidence of miscarriage and pregnancy complications. Although the role of adenomyosis in women undergoing in vitro fertilization (IVF) was investigated in several studies and demonstrated a potentially detrimental effect on live birth rates following IVF, most of them were small studies in which the adenomyosis diagnosis was not confirmed based on solid ultrasonographic criteria. (2) Methods: 3503 patients undergoing their first blastocyst frozen transfer through a hormonal replacement (HRT) FET cycle. Among them, 140 women had a confirmed diagnosis of adenomyosis based on the MUSA criteria. (3) Results: Adenomyosis patients were more likely to proceed with deferred FET compared with no-adenomyosis women (p = 0.002) and were significantly more likely to be treated with GnRH agonist pre-treatment (2 months) (p < 0.001). The presence of adenomyosis significantly decreased the clinical pregnancy rates (aOR 0.62, 95% CI: 0.39-0.98, p = 0.040) and live birth rates (aOR 0.46, 95% CI: 0.27-0.75, p = 0.003) and significantly increased the miscarriage rates (aOR 2.13, 95% CI: 0.98-4.37, p = 0.045). Multivariable logistic regression adjusting for age, autologous or donor oocytes, PGT-A, deferred FET, serum progesterone levels the day before FET, GnRH agonist pre-treatment, number of embryos transferred, and adenomyosis demonstrated that the use of the GnRH agonist protocol did not decrease or increase the miscarriage rate, clinical pregnancy rate, or live birth rate. (4) Conclusions: The presence of adenomyosis had a significant negative impact on the clinical outcomes of patients undergoing FET and was associated with higher miscarriage, lower clinical pregnancy, and live birth rates. GnRH agonist pre-treatment does not appear to improve clinical outcomes.

10.
Rev. senol. patol. mamar. (Ed. impr.) ; 36(3)jul.- sep. 2023. tab, ilus, graf
Artículo en Español | IBECS | ID: ibc-223883

RESUMEN

Introducción: el carcinoma micropapilar infiltrante (CMI) es una variante histológica inusual y potencialmente agresiva caracterizada por primera vez en 1993 por Siriangkul et al. y que no formó parte de la clasificación de la Organización Mundial de la Salud (OMS) hasta 2003, como tumor mamario epitelial. Representa menos del 2% del total de carcinomas invasivos de la mama y se presupone que presenta un pronóstico desfavorable en comparación con otros carcinomas convencionales debido a su elevado tropismo vascular y linfático. Material y métodos: hasta la fecha no existe ningún estudio con un número elevado de pacientes procedentes de un único centro (> 100 casos) con un periodo de seguimiento largo (> 20 años) que compare la supervivencia del CMI con otros carcinomas convencionales no micropapilares. Se ha llevado a cabo un estudio retrospectivo, observacional con un total de 401 pacientes: 174 con CMI y 227 con otros carcinomas convencionales. Resultados: el CMI presenta mayor grado histológico, mayor afectación ganglionar y mayor riesgo de metástasis a distancia en comparación con otros carcinomas convencionales de características similares. Sin embargo, en el análisis multivariante considerando factores pronósticos como edad, tamaño tumoral, afectación ganglionar y grado histológico, no se observan diferencias estadísticamente significativas para la supervivencia global y libre de enfermedad entre los CMI diagnosticados en el mismo periodo de tiempo que los casos pareados del grupo control y otros carcinomas convencionales. Conclusión: la supervivencia global y libre de enfermedad es similar entre el CMI y otros carcinomas convencionales a igual edad, tamaño tumoral, grado histológico y afectación ganglionar. (AU)


Introduction: Invasive Micropapillary Carcinoma of the breast (IMPC) is an unusual and aggressive histological variant characterized for the first time in 1993 by Siriangkul et al. and classified by the World Health Organization in 2003 as an epithelial breast tumor. It represents less than 2% of all invasive carcinomas of the breast and is presumed to have an unfavorable prognosis compared to other conventional carcinomas due to its high vascular and lymphatic tropism. Material and methods: Until now, there is no study with a large number of patients from a single center with a long follow-up period that compares the survival of IMPC with other conventional non-micropapillary carcinomas. A retrospective, observational study has been carried out with a total of 401 patients: 174 with IMPC and 227 with other conventional carcinomas. Results: IMPC has a higher histological grade, greater lymph node involvement and a higher risk of distant metastasis compared to other conventional carcinomas. However, in the multivariate analysis considering date of diagnosis, age, tumor size, lymph node involvement and histological grade as variables, no statistically significant differences were observed for overall and disease- free survival between IMPC and other conventional carcinomas. Conclusion: Overall and disease-free survival is similar between IMPC and other conventional carcinomas considering same age, tumor size, histological grade, and lymph node involvement. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Carcinoma Papilar/diagnóstico , Supervivencia , Estudios Retrospectivos , Estudios Longitudinales , España
11.
Reprod Biomed Online ; 47(3): 103243, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37473718

RESUMEN

RESEARCH QUESTION: Can day-5 blastocysts be ranked according to their likelihood of live birth using an objective and user-friendly grading system? DESIGN: A retrospective multicentre study conducted between 2017 and 2019, including 1044 day-5 blastocysts. Blastocyst expansion degree, trophectoderm and inner cell mass quality were assessed morphologically and morphometrically. Several analyses were conducted: the association between the qualitative and quantitative assessment for the blastocyst expansion degree and the number of trophectoderm cells; the effect of the embryo quality on day 3 and the contribution of the three blastocyst parameters to live birth, with logistic regression; and a decision tree with the most significant variables to create the new scoring system. RESULTS: Cut-off points were found to discriminate between expanding and expanded blastocysts (165 µm for blastocyst diameter) and between trophectoderm grades (A: ≥14 cells; B: 11-13 cells; C: ≤10 cells). When the embryos reached the blastocyst stage, their quality on day 3 did not add predictive value for implantation and live birth. In the logistic regression analysis, the only parameter capable of significantly predicting the live birth likelihood was the trophectoderm grade: A versus C (OR 1.95, 95% CI 1.26 to 3.0); B versus C (OR 1.71, 95% CI 1.22 to 2.4). The decision tree supported the finding that the trophectoderm grade had the highest predictive value for a live birth, followed by the blastocyst expansion degree in a second step. CONCLUSIONS: This new method makes objective blastocyst assessment feasible, allowing for standardization and exportation to other laboratories worldwide.


Asunto(s)
Transferencia de Embrión , Nacimiento Vivo , Embarazo , Femenino , Humanos , Transferencia de Embrión/métodos , Implantación del Embrión , Blastocisto , Embarazo Múltiple , Estudios Retrospectivos
13.
Metabolites ; 13(5)2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-37233655

RESUMEN

Nuclear magnetic resonance (NMR)-based metabolomics is a valuable tool for identifying biomarkers and understanding the underlying metabolic changes associated with various diseases. However, the translation of metabolomics analysis to clinical practice has been limited by the high cost and large size of traditional high-resolution NMR spectrometers. Benchtop NMR, a compact and low-cost alternative, offers the potential to overcome these limitations and facilitate the wider use of NMR-based metabolomics in clinical settings. This review summarizes the current state of benchtop NMR for clinical applications where benchtop NMR has demonstrated the ability to reproducibly detect changes in metabolite levels associated with diseases such as type 2 diabetes and tuberculosis. Benchtop NMR has been used to identify metabolic biomarkers in a range of biofluids, including urine, blood plasma and saliva. However, further research is needed to optimize the use of benchtop NMR for clinical applications and to identify additional biomarkers that can be used to monitor and manage a range of diseases. Overall, benchtop NMR has the potential to revolutionize the way metabolomics is used in clinical practice, providing a more accessible and cost-effective way to study metabolism and identify biomarkers for disease diagnosis, prognosis, and treatment.

14.
Sensors (Basel) ; 23(7)2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37050725

RESUMEN

Individuals with diabetes mellitus type 1 (DM1) tend to check their blood sugar levels multiple times daily and utilize this information to predict their future glycemic levels. Based on these predictions, patients decide on the best approach to regulate their glucose levels with considerations such as insulin dosage and other related factors. Nevertheless, modern developments in Internet of Things (IoT) technology and innovative biomedical sensors have enabled the constant gathering of glucose level data using continuous glucose monitoring (CGM) in addition to other biomedical signals. With the use of machine learning (ML) algorithms, glycemic level patterns can be modeled, enabling accurate forecasting of this variable. Constrained devices have limited computational power, making it challenging to run complex machine learning algorithms directly on these devices. However, by leveraging edge computing, using lightweight machine learning algorithms, and performing preprocessing and feature extraction, it is possible to run machine learning algorithms on constrained devices despite these limitations. In this paper we test the burdens of some constrained IoT devices, probing that it is feasible to locally predict glycemia using a smartphone, up to 45 min in advance and with acceptable accuracy using random forest.


Asunto(s)
Diabetes Mellitus Tipo 1 , Internet de las Cosas , Humanos , Automonitorización de la Glucosa Sanguínea , Glucemia , Aprendizaje Automático
15.
Front Pharmacol ; 14: 1021535, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063275

RESUMEN

Background: Despite increasing evidence suggesting that pulmonary arterial hypertension (PAH) is a complex disease involving vasoconstriction, thrombosis, inflammation, metabolic dysregulation and vascular proliferation, all the drugs approved for PAH mainly act as vasodilating agents. Since excessive TGF-ß signaling is believed to be a critical factor in pulmonary vascular remodeling, we hypothesized that blocking TGFß-activated kinase 1 (TAK-1), alone or in combination with a vasodilator therapy (i.e., riociguat) could achieve a greater therapeutic benefit. Methods: PAH was induced in male Wistar rats by a single injection of the VEGF receptor antagonist SU5416 (20 mg/kg) followed by exposure to hypoxia (10%O2) for 21 days. Two weeks after SU5416 administration, vehicle, riociguat (3 mg/kg/day), the TAK-1 inhibitor 5Z-7-oxozeaenol (OXO, 3 mg/kg/day), or both drugs combined were administered for 7 days. Metabolic profiling of right ventricle (RV), lung tissues and PA smooth muscle cells (PASMCs) extracts were performed by magnetic resonance spectroscopy, and the differences between groups analyzed by multivariate statistical methods. Results: In vitro, riociguat induced potent vasodilator effects in isolated pulmonary arteries (PA) with negligible antiproliferative effects and metabolic changes in PASMCs. In contrast, 5Z-7-oxozeaenol effectively inhibited the proliferation of PASMCs characterized by a broad metabolic reprogramming but had no acute vasodilator effects. In vivo, treatment with riociguat partially reduced the increase in pulmonary arterial pressure (PAP), RV hypertrophy (RVH), and pulmonary vascular remodeling, attenuated the dysregulation of inosine, glucose, creatine and phosphocholine (PC) in RV and fully abolished the increase in lung IL-1ß expression. By contrast, 5Z-7-oxozeaenol significantly reduced pulmonary vascular remodeling and attenuated the metabolic shifts of glucose and PC in RV but had no effects on PAP or RVH. Importantly, combined therapy had an additive effect on pulmonary vascular remodeling and induced a significant metabolic effect over taurine, amino acids, glycolysis, and TCA cycle metabolism via glycine-serine-threonine metabolism. However, it did not improve the effects induced by riociguat alone on pulmonary pressure or RV remodeling. None of the treatments attenuated pulmonary endothelial dysfunction and hyperresponsiveness to serotonin in isolated PA. Conclusion: Our results suggest that inhibition of TAK-1 induces antiproliferative effects and its addition to short-term vasodilator therapy enhances the beneficial effects on pulmonary vascular remodeling and RV metabolic reprogramming in experimental PAH.

16.
J Acoust Soc Am ; 153(4): 1974, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37092919

RESUMEN

We present a new method for the calculation of the multiple acoustic diffraction caused by the presence of a wide barrier. Our solution decomposes the initial scenario into an equivalent sum of geometries that only consider knife-edges. Then, by applying Babinet's principle, the total acoustic field that reaches the receiving point, which can be located at an arbitrary position, can be calculated via the uniform theory of diffraction. This method is mathematically less complex and computationally more efficient than most existing techniques. The results are validated (with and without ground reflection) by the solid agreement obtained with other solutions that solve the problem by considering the wide barrier as such, with our proposed method yielding a lower computational time (except against semi-empirical formulations) and better accuracy when compared with measurements. The presented solution can be applied in urban environments where the impact of traffic noise on residential buildings located along roads or highways needs to be evaluated, as well as in scenarios in which the insertion loss caused by a rectangular obstacle, such as a noise barrier, is to be calculated.

17.
Sensors (Basel) ; 23(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36904943

RESUMEN

Piezoelectric transducers are widely used for generating acoustic energy, and choosing the right radiating element is crucial for efficient energy conversion. In recent decades, numerous studies have been conducted to characterize ceramics based on their elastic, dielectric, and electromechanical properties, which have improved our understanding of their vibrational behavior and aided in the manufacturing of piezoelectric transducers for ultrasonic applications. However, most of these studies have focused on the characterization of ceramics and transducers using electrical impedance to obtain resonance and anti-resonance frequencies. Few studies have explored other important quantities such as acoustic sensitivity using the direct comparison method. In this work, we present a comprehensive study that covers the design, manufacturing, and experimental validation of a small-sized, easy-to-assemble piezoelectric acoustic sensor for low-frequency applications, using a soft ceramic PIC255 from PI Ceramic with a diameter of 10 mm and a thickness of 5 mm. We present two methods, analytical and numerical, for sensor design, followed by experimental validation, allowing for a direct comparison of measurements with simulated results. This work provides a useful evaluation and characterization tool for future applications of ultrasonic measurement systems.

18.
Materials (Basel) ; 16(4)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36837267

RESUMEN

Bone is a heterogeneous, hierarchical biocomposite material made of an organic matrix filled with a mineral component, which plays an important role in bone strength. Although the effect of the mineral/matrix ratio on the mechanical properties of bone during aging has been intensively investigated, the relationship between the mechanical properties and the chemical composition of bone with age requires additional research in juvenile individuals. In this study, bone coupons from bovine and ovine animal species were machined from cortical areas of long bones to quantify whether the variation in mechanical properties at different stages of development is related to the change in the composition of bone tissue. An energy-dispersive X-ray detector (EDX) attached to a scanning electron microscope (SEM) was used to perform a compositional analysis of the tissue. In addition, nanoindentation analyses were carried out to address how the elastic modulus changed with age. Nonparametric statistical analyses found significant differences (p < 0.05) in Ca content and elastic modulus between species, but no differences were found within each species with development. A multiple linear regression model found that the elastic modulus was significantly related to the decrease in P and C in the samples, to the animal species (larger in bovine), and development, although not linearly. This model also found an interaction between Ca and development that could explain the lack of significance of the relationship between the elastic modulus and development in the univariate models.

19.
Diagnostics (Basel) ; 13(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36832299

RESUMEN

(1) Background: This study aims to compare the ground truth (pathology results) against the BI-RADS classification of images acquired while performing breast ultrasound diagnostic examinations that led to a biopsy and against the result of processing the same images through the AI algorithm KOIOS DS TM (KOIOS). (2) Methods: All results of biopsies performed with ultrasound guidance during 2019 were recovered from the pathology department. Readers selected the image which better represented the BI-RADS classification, confirmed correlation to the biopsied image, and submitted it to the KOIOS AI software. The results of the BI-RADS classification of the diagnostic study performed at our institution were set against the KOIOS classification and both were compared to the pathology reports. (3) Results: 403 cases were included in this study. Pathology rendered 197 malignant and 206 benign reports. Four biopsies on BI-RADS 0 and two images are included. Of fifty BI-RADS 3 cases biopsied, only seven rendered cancers. All but one had a positive or suspicious cytology; all were classified as suspicious by KOIOS. Using KOIOS, 17 B3 biopsies could have been avoided. Of 347 BI-RADS 4, 5, and 6 cases, 190 were malignant (54.7%). Because only KOIOS suspicious and probably malignant categories should be biopsied, 312 biopsies would have resulted in 187 malignant lesions (60%), but 10 cancers would have been missed. (4) Conclusions: KOIOS had a higher ratio of positive biopsies in this selected case study vis-à-vis the BI-RADS 4, 5 and 6 categories. A large number of biopsies in the BI-RADS 3 category could have been avoided.

20.
Int J Neural Syst ; 33(4): 2350017, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36846980

RESUMEN

Developmental dyslexia is characterized by a deficit of phonological awareness whose origin is related to atypical neural processing of speech streams. This can lead to differences in the neural networks that encode audio information for dyslexics. In this work, we investigate whether such differences exist using functional near-infrared spectroscopy (fNIRS) and complex network analysis. We have explored functional brain networks derived from low-level auditory processing of nonspeech stimuli related to speech units such as stress, syllables or phonemes of skilled and dyslexic seven-year-old readers. A complex network analysis was performed to examine the properties of functional brain networks and their temporal evolution. We characterized aspects of brain connectivity such as functional segregation, functional integration or small-worldness. These properties are used as features to extract differential patterns in controls and dyslexic subjects. The results corroborate the presence of discrepancies in the topological organizations of functional brain networks and their dynamics that differentiate between control and dyslexic subjects, reaching an Area Under ROC Curve (AUC) up to 0.89 in classification experiments.


Asunto(s)
Dislexia , Percepción del Habla , Humanos , Niño , Mapeo Encefálico , Encéfalo/diagnóstico por imagen , Dislexia/diagnóstico por imagen , Percepción Auditiva , Habla , Lectura
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