This article presents a direct time-of-flight (d-ToF) pulsed light detection and ranging (LiDAR) sensor with interference suppression and a linear-mode receiver implemented using discrete components. ...The sensor achieves 0.3⁰ (horizontal) × 1⁰ (vertical) angular resolution with 60 (H) × 8 (V) pixels using 2D mechanical scanning, covering 18⁰ (H) × 8⁰ (V) field-of-view (FoV). Measurements up to the range of 4.5m using 1D line scanning and a 100kHz laser source, show a frame rate of 16 fps and a precision of 0.2%. Furthermore, a novel coding mechanism is introduced that effectively suppresses interference signals, while adding minimal complexity to the regular time-correlated single-photon counting (TCSPC) processing and without compromising the sensor specifications, such as the maximum range and frame rate. The proposed technique can effectively suppress even very strong interference signals. In general, the proposed technique can provide up to 2 N times interference suppression using N-bit pseudo-random codes. The measurement results show an interference suppression of 15.29 dB using 3-bit pseudo-random coding, which follows the claimed 2 N rule with a good approximation.
Two important drawbacks of parallel coupled LC quadrature oscillators (P-QOSC) which have not heretofore been addressed thoroughly in the literature are obviated simultaneously in this paper. The ...first, has to do with the inevitable off-tune operation of the tank which results in quality factor (Q) degradation, and hence, phase noise deterioration. The other, stems from process, voltage, and temperature (PVT) variations which exacerbate quadrature accuracy. Here, a feedback loop is presented which generates a control signal by mixing the quadrature outputs and tunes the injection strength in the coupled oscillators autonomously. A complex coupling factor is implemented which compensates the phase error to prohibit phase noise degradation. The operation of proposed loop is comprehensively studied mathematically. Measurement results of a 0.18 μm CMOS prototype with an active area of 0.5 mm 2 and an overall power consumption of 5 mW corroborate the functionality of the proposed method. Finally, experimental results prove FoM of 185 dB for the core oscillator and a quadrature phase error of less than 0.8°.
Accurate knowledge of the live birth rate for cleavage stage embryos is essential to determine an appropriate number of embryos to transfer at once. Results from previous studies lack details needed ...for practical use. This is a mathematical analysis and model building study of day 3 cleavage stage embryo transfers. A total of 996 embryos were transferred in 274 fresh and 83 frozen embryo transfers. Embryo morphology was divided into 4 groups based on number of cells and fragmentation percentage. Each embryo transfer was modeled as an equation equating the sum of the live birth rates of the transferred embryos to the number of live births that resulted. The least squares solution to the system of embryo transfer equations was determined using linear algebra. This analysis was repeated for ages 35 to 42 years old at oocyte retrieval. The best fit live birth rates per embryo in the age group centered on 35 years old were 29%, 13%, 10%, and 9% for embryos in the 8-cell with ≤ 5% fragmentation, 8-cell with > 5% fragmentation, 9–12 cell, and 6–7 cell groups, respectively. Cleavage stage embryos with fewer than 6 cells on day 3 had very low best fit live birth rates close to 0% at age 39 years and were excluded from the primary analysis to prevent overfitting. These live birth rates can be used with a simple embryo transfer model to predict rates of single and multiple gestation prior to a planned cleavage stage embryo transfer.
To develop and validate a practical model for quality control monitoring of dichotomous in vitro fertilization (IVF) outcomes such as pregnancy resulting from the transfer of euploid blastocysts.
We ...designed and validated a model for quality control monitoring of dichotomous IVF outcomes. We demonstrate use of this model for assessment of euploid blastocyst transfer quality control based on fetal heartbeat rate per embryo. The model uses 3 weighted moving averages with window sizes of 21, 51, and 101 embryo transfers to detect short and long-term shifts in success rates. The quality warning limit was set to have a 2-sided type I error rate of 0.30 per 100 embryo transfers and the control limit was set to have a type I error rate of 0.05 per 100 embryo transfers. Simulation studies were performed to validate the model through assessment of type I and type II errors using custom computer programs.
Not applicable.
Patients undergoing IVF.
None.
Type I and type II error rates and statistical power analysis.
Validated quality warning and control limits are presented for a range of expected outcome rates. The power to detect a 20% decrease from an expected fetal heartbeat rate of 50%, when the decrease persisted for 50 embryo transfers, was 86% for the warning limit and 57% for the control limit.
This model can be used for continuous quality control assessment of dichotomous IVF outcomes such as pregnancy rates.
Diseño y validación de un modelo de monitorización de control de calidad de resultados dicotómicos en fecundación in vitro.
Desarrollar y validar un modelo práctico de control de calidad para la monitorización de resultados dicotómicos en fecundación in vitro (IVF) como es: gestación resultante de transferencias de blastocistos euploides.
Diseñamos y validamos un modelo para la monitorización del control de calidad de los resultados dicotómicos de IVF. Demostramos el uso de este modelo para evaluar la transferencia de blastocistos euploides basado en la tasa de latido cardíaco fetal por embrión. El modelo utiliza 3 medias móviles ponderadas con tamaños de ventana de 21, 51 y 101 transferencias de embriones, para detectar desplazamientos de las tasas de éxito a corto y largo plazo. El límite de alarma de calidad se puso para tener una tasa de error tipo I de 2 colas de 0.30 por cada 100 transferencias de embriones. Se realizaron estudios de simulación para validar el modelo a través de la valoración de los errores tipo I y tipo II utilizando programas de ordenador a medida.
No aplica.
Pacientes en tratamiento de IVF.
Ninguna.
tasas de errores tipo I y tipo II y análisis de la potencia estadística.
Se presentan unos límites validados de calidad, de alarma y de control, para un rango de tasa de resultados esperado. La potencia para detectar una disminución de un 20% de una tasa esperada de latido cardiaco fetal del 50%, cuando la disminución persistió más allá de 50 transferencias embrionarias, fue del 86% para el límite de alarma y del 57% para el límite de control.
Este modelo puede utilizarse para la evaluación del control de calidad continua de resultados dicotómicos de IVF tales como la tasa de gestación.
To determine the accuracy of cell-free DNA (cfDNA) in spent embryo medium (SEM) for ploidy and sex detection at the cleavage and blastocyst stages. To determine if assisted hatching (AH) and ...morphologic grade influence cfDNA concentration and accuracy.
Prospective cohort.
Academic fertility center.
Nine patients undergoing IVF; 41 donated two-pronuclei embryos and 20 embryos from patients undergoing preimplantation genetic testing for aneuploidy (PGT-A).
In a donated embryo arm, SEM was collected on days 3 and 5, with one-half of the embryos undergoing AH before and one-half after. In a clinical arm, SEM was collected on day 5 before trophectoderm (TE) biopsy. Samples underwent PGT-A with the use of next-generation sequencing. cfDNA results were compared with corresponding whole embryos and TE biopsies.
Concordance rates, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for ploidy and sex detection with the use of cfDNA.
Of 141 samples, cfDNA was amplified in 39% and 80.4% of days 3 and 5 SEM, respectively. Concordances for ploidy and sex, respectively, were 56.3% and 81.3% between day 3 cfDNA and whole embryos, and 65% and 70% between day 5 cfDNA and TE biopsies. Day 5 cfDNA sensitivity and specificity for aneuploidy were 0.8 and 0.61, respectively. PPV and NPV were 0.47 and 0.88, respectively. Timing of AH and morphology did not influence cfDNA concentration or accuracy.
cfDNA is detectable on days 3 and 5, but more accurate on day 5. Although our data suggest moderate concordance rates, PGT-A with the use of cfDNA must be further optimized before clinical implementation.
Ampliando los límites de detección: la investigación de ADN celular libre en la detección de aneuploidías en embriones
Determinar la precisión del ADN celular libre (ADNcl) en el medio de cultivo utilizado por los embriones (MUE) para la detección de ploidías y el sexo en los estadíos de división celular y blastocisto. Determinar si la eclosión asistida (EA) y el grado de morfología influyen en la concentración y precisión del ADNcl.
Estudio prospectivo.
Centro académico de fertilidad.
Nueve pacientes sometidas a FIV; 41 embriones de dos pronúcleos donados y 20 embriones de pacientes sometidas a la prueba genética preimplantatoria para aneuploidías (PGP-A).
En la rama de los embriones donados, el MUE fue obtenido en los días 3 y 5, en una mitad de los embriones se obtuvo antes de la EA y en la otra mitad después. En la rama clínica, el MUE fue obtenido en el día 5 antes de la biopsia de trofoectodermo (TE). Las muestras fueron sometidas a PGP-A con el uso secuenciación de última generación. Los resultados de ADNcl fueron comparados con su correspondiente embrión completo y con la biopsia de TE.
Tasas de concordancia, sensibilidad, especificidad, valor predictivo positivo (VPP) y valor predictivo negativo (VPN) para la detección de ploidías y el sexo con el uso de ADNcl.
En 141 muestras, el ADNcl fue amplificado en el 39% y 80,4% para los MUE de días 3 y 5, respectivamente. Las concordancias entre ploidías y el sexo fueron del 56,3% y 81,3% para el ADNcl de día 3 y embriones completos respectivamente, y el 65% y 70% para el ADNcl de día 5 y las biopsias de TE. La sensibilidad y especificidad del ADNcl para aneuploidías en día 5 fueron 0,8 y 0,61, respectivamente. El VPP y el VPN fueron 0,47 y 0,88 respectivamente. El tiempo en que se realizó la EA y la morfología no influyeron en la concentración ni en la precisión del ADNcl.
El ADNcl es detectable en los días 3 y 5, pero es más preciso en el día 5. Aunque nuestros datos sugieren tasas moderadas de concordancia, el PGP-A con el uso de ADNcl debe optimizarse aún más antes de su implementación clínica.
Boost converter operating in critical conduction mode is widely used in low-power power factor corrector because of its simplicity and low switching losses. The switching loss due to parasitic ...capacitor discharge at the on-time instant can also be reduced by a valley switching technique. In this paper, we introduce a new driver topology for the high-side switch in a synchronous boost converter operating in the critical conduction mode to obtain full zero-voltage switching. Using the proposed high-side driver topology, the conventional control circuit is sufficient to control the low-side switch, and no additional control circuit is required to adjust the timing of the switches. Finally, the line current distortion is reduced through the use of on-time extension technique to less than 10% in the defined load range. Based on approximate mathematical calculations, two separate distortion reduction circuits are designed to implement the on-time extension technique for both voltage-mode and current-mode control methods.
Sensors are among essential building blocks of any Cyber-Physical Systems (CPSs). Acquisition and processing of their sensory data contribute to the power consumption and computation load of the ...overall CPSs. For data acquisition, the conventional fixed frequency sampling in many such systems is sub-optimal since a sizable number of samples do not contain important information. In this work, we propose a Signal-Dependent Sampling (SDS) method and present its associated circuit implementation. Using the proposed SDS method, the number of retained samples is significantly reduced with little or negligible compromise in the quality of the (reconstructed) signal. The associated error and added noise are analyzed and their boundaries - which can be controlled by the user - are calculated. Our experiments show that the proposed system is able to improve power efficiency of the overall system in various applications. For example, for wireless Electrocardiography (ECG), Photoplethysmography (PPG), and Electroencephalogram (EEG) monitoring systems, the proposed approach can achieve a power saving of 81%, 76%, and 64% respectively. The proof-of-concept prototype system is implemented using TSMC <inline-formula> <tex-math notation="LaTeX">0.18~\mu \text{m} </tex-math></inline-formula> and has a foot-print and power consumption that compare favorably with those of the state-of-the-art implementations. The method can be used in a variety of applications including wireless sensor networks, mobile and wearable devices, as well as Internet of Things (IoT) nodes.
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