The transistor threshold voltage mismatch and sensing noise are larger with technology scaling, while the sensing voltage difference of bit-line sense amplifier becomes smaller. Though various offset ...calibration techniques have been adopted in bit-line sense amplifiers to compensate for the offset mismatch, sensing offset and noise are still critical issues to limit the sensing margin. This brief proposes a bit-line sense amplifier with asymmetrically controlled isolation devices to solve the sensing offset and sensing noise problems simultaneously. Being biased to the calibration point, the target inverter acts as an amplifier with a large voltage gain (AV) to boost the sensing voltage difference, making the sensing voltage difference of the proposed amplifier be 1 + |AV| times that of a conventional latch-type sense amplifier. And the pre-sensing operation performs in parallel with boosting to suppress the sensing noise, without additional time and area consumption. By offset calibration and voltage difference boosting techniques, the proposed design has suppressed the sensing noise and enhanced the sensing margin. All designs are implemented on SMIC 40-nm technology, operating at a supply voltage of 1.05 V or less. The proposed sense amplifier has reduced the standard deviation of the decision threshold voltage to 0.62× and improved the sensing yield by 17.96%. In addition, the boosted sensing voltage difference speeds up the sensing stage, compensating for the pre-sensing time by 36%. Keeping the same number of transistors as the prior offset mismatch calibration sense amplifier, the proposed sense amplifier with improved sensing margin is suitable for low-voltage and high-density DRAM.
•Isolation transistors are asymmetrically controlled and time-share enabled.•The sensing voltage difference is boosted to be (1 + |AV |) times that of a conventional sense amplifier.•The pre-sensing operation performs in parallel with the snesing voltage difference boosting operation.•The standard deviation of the decision threshold voltage is reduced by 0.62 × .•The sensing yield is over 84% at 0.80 V, which is higher than that of the prior work at 1.05 V.
Abstract only Introduction: A challenge with clinical trials is the capacity to identify a population that may potentially benefit from the intervention that is not “too well” (will recover) or “too ...sick” (will not survive) regardless of intervention. While inclusion criteria attempt to obtain this, populations enrolled in trials include pts in which bedside clinicians would be able to categorize in terms of likelihood of survival independent of study intervention. We further hypothesize that patients categorized as having an uncertain outcome would be most likely to benefit from the intervention. Methods: We present subgroup analyses of patients from the Thiamine as a Metabolic Resuscitator in Cardiac Arrest (THACA) trial in patients with out of hospital cardiac arrest and the Ascorbic Acid, Corticosteroids and Thiamine in Sepsis (ACTS) trial in patients with septic shock. The treating physician predicted at the time of enrollment whether the patient is “very likely”, “very unlikely”, or ”uncertain” to be alive at 30 days. Results: Among 31 pts in the THACA trial with physician predictions, 12/31 (39%) were predicted very unlikely to be alive on day 30, 3/31 (10%) very likely, and 16/31 (52%) uncertain. Among 200 pts in the ACTS trial, 13/200 (7%) of patients were predicted as very unlikely, 72/201 (36%) very likely and 115/201 (57%) uncertain. Predicted mortality was associated with observed mortality in both trials(p = 0.04, p<0.001). When evaluating the primary outcome in the population categorized as uncertain, there was a non-significant shift in favor of the intervention in THACA (p = 0.69); and a difference favoring the intervention in ACTS (p = 0.03) as opposed to the overall cohort which did not reach statistical significance (p = 0.12). Conclusion: In two RCTs in patients with cardiac arrest and septic shock, physicians reliably predicted mortality. Restricting analyses to pts with an uncertain outcome, the primary outcome in one trial changed from trending toward favoring the intervention to a statistically significant difference. The second trial shifted in favor of the outcome but did not reach statistical significance. These findings suggest that physician prediction may be a potential method to target patients with the greatest chance to benefit from clinical trials.
Intelligent aeroengine requires high temperature sensors, especially MEMS thin film sensors directly fabricated on the surface of turbine blade. For this purpose, an electrical insulation layer is ...needed on blade substrate metals. However, the electrical insulation of ceramic materials will degrade at high temperatures, thereby affecting the characteristics of the sensor. In this paper, ceramic material of YSZ thermal barrier coating (TBC) formulation was modified by adding a certain amount of Al2O3 to improve its insulation at high temperatures. Micro processing was carried out on the surface of the TBC, including the fabrication of platinum-point thermocouples and thermal resistor on TBC surface, and high temperature electrical insulation properties of the modified TBC were studied. Results show that electrical insulation can be improved several orders of magnitude with adding Al2O3 which meets the requirement to build reliable thin film sensors on the top of TBC surface coated on turbine blade metals. Several verification experiments were carried out to ensure the working ability of TBC layer, including robustness test, thermal shock test and high temperature retention test.
Older adults have been hit disproportionally hard by the COVID-19 pandemic. One critical way for older adults to minimize the negative impact of COVID-19 and future pandemics is to stay informed ...about its latest information, which has been increasingly presented through online interactive visualizations (e.g., live dashboards and websites). Thus, it is imperative to understand how older adults interact with and comprehend online COVID-19 interactive visualizations and what challenges they might encounter to make such visualizations more accessible to older adults. We adopted a user-centered approach by inviting older adults to interact with COVID-19 interactive visualizations while at the same time verbalizing their thought processes using a think-aloud protocol. By analyzing their think-aloud verbalizations, we identified four types of thought processes representing how older adults comprehended the visualizations and uncovered the challenges they encountered with these thought processes. Furthermore, we also identified the challenges they encountered with seven common types of interaction techniques adopted by the visualizations. Based on the findings, we present design guidelines for making interactive visualizations more accessible to older adults.
•In this paper, surface acoustic wave (SAW) devices with various designs were fabricated on two types of piezoelectric substrates of LiNbO3 bulk material and thin piezoelectric ZnO film on ...silicon.•Different sizes, orientation and types of SAW devices were laid out on the same mask to compare their RF performance with a same fabrication.•Devices were fabricated using lift-off technology with a double photoresist technique to achieve a steeper and narrower SAW pattern with a depth-to-width ratio of 1.27 and a steep resist angle of 85°.•The devices were then characterized using RF probe station together with vector network analyzer.•RF performance was also verified by 2D computer simulation implementing both electrical and piezoelectric physics models using the same device dimensions in the mask layout.•RF response of 128°Y LiNbO3 from experiments agrees with simulation fairly well while the devices on ZnO/Si have larger frequency distribution due to process variation of the ZnO thin film on silicon wafer.•Quality factor of 34,000 was obtained from the SAW device fabricated in LiNO3 substrate and this Q value has a strong dependency on the numbers electrodes of IDT fingers and reflectors.•Temperature dependency was also measured for future wireless sensor application.•The temperature coefficient of frequency of 16 μm wavelength devices of LiNbO3 substrate was −87.5 ppm/°C and was −72.41 ppm/°C for 12 μm wavelength devices.
In this paper, surface acoustic wave (SAW) devices with various designs were fabricated on two types of piezoelectric substrates of LiNbO3 bulk material and thin piezoelectric ZnO film on silicon. Different sizes, orientation and types of SAW devices were laid out on the same mask to compare their RF performance with a same fabrication. Devices were fabricated using lift-off technology with a double photoresist technique to achieve a steeper and narrower SAW pattern with a depth-to-width ratio of 1.27 and a steep resist angle of 85°. The devices were then characterized using RF probe station together with vector network analyzer. RF performance was also verified by 2D computer simulation implementing both electrical and piezoelectric physics models using the same device dimensions in the mask layout. RF response of 128°Y LiNbO3 from experiments agrees with simulation fairly well while the devices on ZnO/Si have larger frequency distribution due to process variation of the ZnO thin film on silicon wafer. Quality factor of 34,000 was obtained from the SAW device fabricated in LiNO3 substrate and this Q value has a strong dependency on the numbers electrodes of IDT fingers and reflectors. Temperature dependency was also measured for future wireless sensor application. The temperature coefficient of frequency of 16 μm wavelength devices of LiNbO3 substrate was −87.5 ppm/°C and was −72.41 ppm/°C for 12 μm wavelength devices.
Solidly mounted resonators (SMRs) rely on high-quality Bragg reflectors, for which tungsten has been used as the high acoustic impedance layer. It is unclear about the effects of tungsten phases on ...the acoustic performance of SMRs. In this study, high-quality flat layers of different phase structures of W (α-W and β-W) are obtained by changing the post-growth annealing temperature and magnetron sputtering parameters. Our results show that the α-W has higher Young's modulus and acoustic impedance (205 GPa and 63 kg/m2s) than β-W (170 GPa and 57 kg/m2s). These small differences result in amplified difference in acoustic performance of Bragg reflectors using tungsten (W) as their high-impedance layer. Our tests show that the SMR of α-W Bragg reflector has a higher return loss (18.4 dB) at around 2.75 GHz and higher quality factor (687) than that of β-W Bragg reflector (9.2 dB and 228, respectively).
•Different phase structures of W are obtained by changing the annealing temperature and magnetron sputtering parameters.•The acoustic impedance of α-W is 10% higher than that of β-W.•The influence of α- and β-W phases on performance of SMR devices is different.
Thiamine is a key cofactor for aerobic metabolism, previously shown to improve mortality and neurological outcomes in a mouse model of cardiac arrest. We hypothesized that thiamine would decrease ...lactate and improve outcomes in post-arrest patients.
Single center, randomized, blinded, placebo-controlled, Phase II trial of thiamine in adults within 4.5 hours of return of spontaneous circulation after out-of-hospital cardiac arrest (OHCA), with coma and lactate ≥ 3 mmol/L. Participants received 500 mg IV thiamine or placebo twice daily for 2 days. Randomization was stratified by lactate > 5 or ≤ 5 mmol/L. The primary outcome of lactate was checked at baseline, 6, 12, and 24 hours, and compared using a linear mixed model to account for repeated measures. Secondary outcomes included SOFA score, pyruvate dehydrogenase, renal injury, neurological outcome, and mortality.
Of 93 randomized patients, 76 were enrolled and included in the analysis. There was no difference in lactate over 24 hours (mean difference 0.34 mmol/L (95% CI: −1.82, 2.50), p = 0.43). There was a significant interaction between randomization lactate subgroup and the effect of the intervention on mortality (p = 0.01) such that mortality was higher with thiamine in the lactate > 5 mmol/L group and lower with thiamine in the < 5 mmol/L group. This subgroup difference prompted the Data and Safety Monitoring Board to recommend the study be terminated early. PDH activity increased over 72 hours in the thiamine group. There were no differences in other secondary outcomes.
In this single-center randomized trial, thiamine did not affect lactate over 24 hours after OHCA.
Elevated lactate is associated with mortality after cardiac arrest. Thiamine, a cofactor of pyruvate dehydrogenase, is necessary for aerobic metabolism. In a mouse model of cardiac arrest, thiamine ...improved pyruvate dehydrogenase activity, survival and neurologic outcome.
To determine if thiamine would decrease lactate and increase oxygen consumption after in-hospital cardiac arrest.
Randomized, double-blind, placebo-controlled phase II trial. Adult patients with arrest within 12 hours, mechanically ventilated, with lactate ≥ 3 mmol/L were included. Randomization was stratified by lactate > 5 or ≤ 5 mmol/L. Thiamine 500 mg or placebo was administered every 12 hours for 3 days. The primary outcome of lactate was checked at baseline, 6, 12, 24, and 48 hours, and compared using a linear mixed model, accounting for repeated measures. Secondary outcomes included oxygen consumption, pyruvate dehydrogenase, and mortality.
Enrollments stopped after 36 patients due Data Safety and Monitoring Board concern about potential harm in an unplanned subgroup analysis. There was no overall difference in lactate (mean difference at 48 hours 1.5 mmol/L 95% CI −3.1–6.1, global p = 0.88) or any secondary outcomes. In those with randomization lactate > 5 mmol/L, mortality was 92% (11/12) with thiamine and 67% (8/12) with placebo (p = 0.32). In those with randomization lactate ≤ 5 mmol/L mortality was 17% (1/6) with thiamine and 67% (4/6) with placebo (p = 0.24). There was a significant interaction between randomization lactate and the effect of thiamine on survival (p = 0.03).
In this single center trial thiamine had no overall effect on lactate after in-hospital cardiac arrest.
