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Introduction: In neonatal period, brain magnetic resonance imaging (MRI) is the best neuroimaging to find etiology of seizure. The aim of this study was to evaluate brain MRI findings of neonates with clinical seizure and its effect on diagnostic and therapeutic interventions of newborn. Methods: In a retrospective study, medical records and brain MRI findings of neonates with clinical seizure admitted to Neonatal Intensive Care Unit or Pediatric Ward of Shahid Sadoughi Hospital, Yazd, Iran from September 2018 and before were evaluated. The data were analyzed using SPSS version 16 software , the required indicators and tables were prepared and Fisher exact test and Chi-square test were used to determine the relationship between qualitative variables and independent t-test was used to compare the means in the two groups Results: Twenty-five girls and 38 boys were studied. The cause of seizures was found in 94% and the most common cause of congenital hypoxia was in 22 infants (35%). The most common type of seizure was tonic in 23 infants (36.5%) and the most common type of generalized seizure was in 47 infants (75%). Brain MRI was abnormal in 19 neonates (30%). Based on the MRI results, there was a change in therapeutic interventions (brain surgery) in four infants (6.3%) and in diagnostic interventions (metabolic tests) in 19 infants (30%). Abnormal brain MRI was more frequent in neonates by cesarean section (46%) than normal vaginal delivery (19%), (p= 0.01) and also neonates with partial seizure (37.5%) had an abnormal MRI than generalized seizure (21%), (p= 0.03). Mean of hospitalization days was longer in neonates with abnormal brain MRI (12.32±2.76 days) than neonates with normal MRI (8.57±2.82 days) (P = 0.02). Conclusion: Based on the results of this study, brain MRI might be useful in finding intracranial pathology that causes seizure in neonates by cesarean section to detect birth asphyxia and in newborns with partial seizure.

Producción Científica, The relentless scaling of semiconductor devices pushes the doping level far above the equilibrium solubility, yet the doped material must be sufficiently stable for subsequent device fabrication and operation. For example, in epitaxial silicon doped above the solubility of phosphorus, most phosphorus dopants are compensated by vacancies, and some of the phosphorus-vacancy clusters can become mobile around 700 °C to further cluster with isolated phosphorus ions. For efficient and stable doping, we use microwave annealing to selectively activate metastable phosphorus-vacancy clusters by interacting with their dipole moments, while keeping lattice heating below 700 °C. In a 30-nm-thick Si nanosheet doped with 3 × 1021 cm−3 phosphorus, a microwave power of 12 kW at 2.45 GHz for 6 min resulted in a free-electron concentration of 4 × 1020 cm−3 and a junction more abrupt than 4 decades/nm. The doping profile is stable with less than 4% variation upon thermal annealing around 700 °C for 5 min. Thus, microwave annealing can result in not only efficient activation and abrupt profile in epitaxial silicon but also thermal stability. In comparison, conventional rapid thermal annealing can generate a junction as abrupt as microwave annealing but 25% higher sheet resistance and six times higher instability at 700 °C., Supplemental material: Efficient and stable activation by microwave annealing of nanosheet silicon doped with phosphorus above its solubility limit, Ministry of Science and Technology of Taiwan (Contract MOST 109-2628-M-008-004-MY3)

A closed-loop capacitance sensing and control mixed-signal CMOS circuit with a dedicated sensor electrode and a proportional-integral controller was designed to have a sensitivity of 1 fF, a settling time of $200~\mu \text{s}$ , and a voltage capacity of 150 V. In a hybrid integration with a MEMS varactor, the control circuit could switch the varactor capacitance from 270 to 365 fF in 15 ms and hold it within ±2% between 25 °C and 80 °C. Furthermore, using the varactor as the tuning element of a substrate-integrated-waveguide (SIW) resonator, the control circuit could tune its resonance frequency from 33.2 to 33.9 GHz while keeping it within ±0.08% over a temperature range of 25 °C–90 °C. The control circuit occupied an area of 1.7 mm2 and consumed 6 mW. The present closed-loop-controlled MEMS-tunable resonators could be used in a quartz SIW multi-pole filter to realize tunable, small, light, low-cost, robust, and reliable millimeter-wave filters that are critical to 5G and other future-generation communication and radar systems.

Substrate-integrated waveguides (SIWs) of different geometry are designed, fabricated, and measured on a SiC wafer, along with SIW-based resonators, SIW-based filters, grounded coplanar waveguides (GCPWs), GCPW-SIW transitions, and calibration structures. Two-tier calibration is used to extract the intrinsic SIW characteristics from GCPW-probed scattering parameters. The resulted D-band (110–170 GHz) SIWs exhibit a record low insertion loss of 0.22 ± 0.04 dB/mm, which is four times better than that of the GCPWs. A 3-pole filter exhibits a 1.0-dB insertion loss and a 25-dB return loss at 135 GHz, which represents the state of the art of SiC SIW filters and is order-of-magnitude better than Si on-chip filters. These results show the promise of SIWs for integrating HEMTs, filters, antennas, and other circuit elements on the same SiC chip.

This paper reports the temperature-dependent ferroelectric properties of sputtered ferroelectric Al 0.70 Sc 0.30 N. The coercive field is experimentally demonstrated to decrease by 1.5 MV/cm in 300 nm films in the temperature range of 20– 193 0C, corresponding to an average linear coefficient of decrease of 8.8 kV/0C. In the same range, the remnant polarization varies by 23.5% between 90-114 µC/cm2 without a significant drop-off at higher temperatures. Thermally cycling the chip between room temperature and the highest achievable temperature of 193 0C shows a reversible tuning of the coercive field, paving the path towards on-chip ovenization-based control of ferroelectric properties. The dielectric breakdown under AC and DC testing are driven by filamentary and thermally driven breakdown processes respectively. These breakdown processes suggest the potential for high frequency operation of sputtered Al 0.70 Sc 0.30 N as a ferroelectric thin film at elevated temperatures with low leakage.

Using epitaxial aluminum nitride (AlN) developed for ultraviolet photonics and high-speed electronics, we demonstrate suspended AlN thin-film bulk acoustic resonators (FBARs) at 9.2 GHz in the X-band (8–12 GHz) of the microwave spectrum. The resonators show a [Formula: see text] and a figure of merit [Formula: see text] THz. The material stack of these epi-AlN FBARs allows monolithic integration with AlN/GaN/AlN quantum well high-electron-mobility-transistors to a unique RF front end and also enable integration with epitaxial nitride superconductors for microwave filters for quantum computing.

A CMOS closed-loop control circuit was designed, fabricated, and tested for order-of-magnitude improvement of the robustness of a MEMS varactor against ambient temperature change. The control is based on real-time sensing of the capacitance of the MEMS varactor and fine-tuning its bias voltage according to the difference between the sensed and targeted capacitances. Simulation shows that this difference can be sensed with femtofarad sensitivity and a linear output over a piccofarad dynamic range. Measurement shows that, in a hybrid integration of the CMOS control circuit and the MEMS varactor, the varactor capacitance can be kept within ±2% of the targeted value despite a temperature change from 25°C to 80 °C. When the MEMS varactor is used as the tuning element of a substrate-integrated-waveguide (SIW) resonator, the control circuit can maintain the resonance frequency within ±0.08% over the temperature variation.

Due to the complexities of design and technical issues of construction, tunnels are considered to be enormous financial investments. Therefore, rehabilitation with the purpose of providing a higher life span is essential. Underground facilities usually have a higher service period than expected when designed, which often requires regular inspection. This study aims at providing a guideline for future tunnel investigations and maintenance. Offered solutions with regard to different cases of an anomaly for three available tunnels in the Ilam province have been introduced. These currently servicing tunnels are usually constructed as unlined rock tunnels excavated, using controlled blasting. Masonry, reinforced concrete, and shotcrete lining systems have been used in the collapsible zones. These infrastructures as part of the transportation network of the Ilam province in Iran are located in one of the most active seismic, as well as high rainfall zones in the Middle East. Aging and degradation of material alongside recent earthquake activities can lead to massive destruction of the tunnels if regular maintenance work doesn't take place. All tunnels were evaluated using advanced numerical analysis methods. Stress and displacement values ​​in the rock mass and different lining systems have been investigated using various analytic methods and the rehabilitation programs for tunnels were developed and introduced. The high risk of failure in the tunnel in the Payambar tunnel is predicted in cases of a seismic event affected by the inclination of rock layers. Methods of rehabilitation have been proposed to improve stability and decrease deformations. The formation of icicles in the Azadi tunnel during the cold seasons have been solved through employing a temporary water drainage system. Unlined tunnel sections were planned to be covered with reinforced concrete lining and both cast-in-place and precast segmental lining systems have been proposed. In the Shabab tunnels an extremely disturbed, 2–3 m deep rock layer was found between the masonry lining and the top of the tunnels, due to its controlled blasting excavation technique. Filling the voids using a pressure grouting technique was discovered in order to improve the tunnel stability during an earthquake event.

This paper proposes a novel structure for realization of the OR/NOR logic gates. The structure, consists of a Λ-type 3-level quantum dot localized in a single mode photonic crystal cavity and coupled symmetrically to two different parallel waveguides. The probe field is guided by the two waveguide while the control field is applied vertically to the photonic crystal cavity. Absence of the control field results propagation of the probe field in waveguide and mutually, in the presence of the control field, probe field switches to the other waveguide. Two data stream are combined by a coupler and it constructs the control filed. The finite-difference time-domain algorithm are used for solving coupled Heisenberg equations. Simulations and results show that the proposed logic gates can operate at the range of up to 5 Gb/s.

To make MEMS varactors more robust and reliable, a closed-loop control circuit was designed to sense the varactor capacitance and tune the MEMS bias in real time to adjust the capacitance to the desired value within 1 fF and in 200 $\mu$s. The designed circuit was successfully implemented in a standard RF CMOS technology despite the challenge for handling high voltage at high speed and for suppressing the substrate-coupled noise. The fabricated chip was tested to function according to the design simulation and to be capable of switching 150 V repeatedly.

A 3-D thermal analysis of 870 nm high-index-contrast grating (HCG)-based vertical cavity surface emitting laser (VCSEL) by using finite volume method (FVM) is presented in this paper. The HCG-based VCSEL is modeled by applying a steady-state 3-D heat dissipation model. Temperature distribution profile and thermal resistance ( R th ) of the device are investigated by inserting the heat source value into the thermal simulation. Also, this analysis is performed for a conventional VCSEL operating at the same wavelength and under the same injected current as well as the same geometric sizes. The analysis shows that the maximum temperature inside the HCG-based VCSEL is lower than that inside the conventional VCSEL.

This paper proposes a design for all-optical NOR logic gate, based on Mach-Zehnder interferometer (MZI) using quantum-dot semiconductor optical amplifier (QD-SOA). In this regard, a theoretical model for an ultrafast all-optical signal processor is developed using QD-SOA to achieve high bit rate operation. We have demonstrated the NOR gate operation in two cases of with and without an optical control pulse. Simulations have been carried out at data bit rates 160 Gb/s, 200 Gb/s, and 250 Gb/s for the case that control pulse is not applied, and also at data bit rates 1 Tb/s and 2 Tb/s in presence of control pulse which leads to improvement of gain recovery time and ultrafast NOR logic operation. In addition, quality factors of the output signals in presence and without the control pulse at different bit rates with different bias currents have been investigated for pseudo-random binary sequence (PRBS) of word length 28–1.

Previously, the design of our novel low-dispersion phase-shifter unit cell with two asynchronous MEMS switches was limited to 90°, so that four unit cells (90°, 90°, 90° and 45°) with a total of eight MEMS switches were required for a 3-bit phase shifter. This not only increased the size and loss of the phase shifter, but also decreased its yield and reliability. Recently, we hypothesized that by using two synchronized MEMS switches, the phase shift of a unit cell could be extended to 180° so that only three unit cells (180°, 90° and 45°) with a total of six MEMS switches would be required for a 3-bit phase shifter. This paper confirms the hypothesis with measured characteristics of a fabricated 180° phase-shifter unit cell. The measured characteristics compare well with both equivalent-circuit model prediction and three-dimensional finite-element electromagnetic simulation, provided the worse-than-expected loss from individual MEMS switches is taken into account. The results provide the proof of the design principle, so that with improved MEMS fabrication process such as thicker metallization, the switch loss can be reduced and low-dispersion phase shifters can be realized with compact size, low loss, low cost, and high reliability.

This paper reports a low-dispersion metamaterial-based 3-bit phase shifter which occupies an area of approximately 5 mm2 and uses only six microelectromechanical systems (MEMS) switches. The phase shifter is based on a coplanar slow-wave structure with defected ground and comprises three unit cells of 180°, 90° and 45° phase shifts, respectively. Each unit cell uses two single-pole-single-throw MEMS capacitive switches in series and parallel configurations, respectively, to switch between right-handed (low-pass) and left-handed (high-pass) states for the specified phase shift. Three-dimensional finite-element electromagnetic simulation was used to help optimize the compact layout. The worst-case performance across the band of 24–28 GHz was simulated to have less than 9° root-mean-square phase error, less than 1.7 dB insertion loss, and greater than 13 dB return loss.