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111.
The valence-band electron (EVB) tunneling current in partially depleted silicon-on-insulator (SOI) MOSFETs increases as the gate oxide gets thinner and affects the dynamic behavior of devices and circuits. We present an engineering model of EVB tunneling current based on the surface-potential formulation. The new model is implemented in a SOI MOSFET compact model and is used to study the impact of EVB tunneling on circuit performance. Simulations of stacked logic gates show that the EVB tunneling current not only boosts circuit switching speed but also mitigates the history dependence of propagation delays  相似文献   
112.
Despite superior outcomes and lower associated costs, relatively few patients with end‐stage renal disease undergo self‐care or home hemodialysis. Few studies have examined patient‐ and physician‐specific barriers to self‐care and home hemodialysis in the modern era. The degree to which innovative technology might facilitate the adoption of these modalities is unknown. We surveyed 250 patients receiving in‐center hemodialysis and 51 board‐certified nephrologists to identify key barriers to adoption of self‐care and home hemodialysis. Overall, 172 (69%) patients reported that they were “likely” or “very likely” to consider self‐care hemodialysis if they were properly trained on a new hemodialysis system designed for self‐care or home use. Nephrologists believed that patients were capable of performing many dialysis‐relevant tasks, including: weighing themselves (98%), wiping down the chair and machine (84%), clearing alarms during treatment (53%), taking vital signs (46%), and cannulating vascular access (41%), but thought that patients would be willing to do the same in only 69%, 34%, 31%, 29%, and 16%, respectively. Reasons that nephrologists believe patients are hesitant to pursue self‐care or home hemodialysis do not correspond in parallel or by priority to reasons reported by patients. Self‐care and home hemodialysis offer several advantages to patients and dialysis providers. Overcoming real and perceived barriers with new technology, education and coordinated care will be required for these modalities to gain traction in the coming years.  相似文献   
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114.
ABSTRACT

Night-time cloud detection provides data sets of cloud-cover percentage. Although night-time cloud-cover data sets from satellite-based instruments are common, these data sets do not have relatively high temporal resolution. To quantify local temporal cloud-cover variability and to attain long-term cloud-cover measurements, ground-based instruments would be the appropriate apparatus. In this study, a digital camera is used to continuously gather images of the night sky at 5-min intervals over Manila Observatory (14.64° N, 121.07° E). For the first time in Manila, ground-based remote-sensing data gathered from October 2015 to October 2016 are analysed for hourly cloud cover. The results indicate that wet season has relatively higher cloud-cover values (median >40%) as compared to the dry season (median <40%). Moreover, cloud-cover values are observed to decrease during the night. For the wet season, August having the highest cloud-cover values has the highest value of change of hourly cloud-cover percentage (?0.82% h?1). For the dry season, February having the lowest cloud-cover values has the highest value of change of hourly cloud-cover percentage (?1.04% h?1).  相似文献   
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116.
The induction of c-Fos-like immunoreactivity (c-FLI) in the nucleus of the solitary tract (NTS) has been shown to be correlated with behavioral expression of a conditioned taste aversion (CTA). However, because this cellular response is also dependent on an intact amygdala, it may represent the activation of a stress-related autonomic response. The present experiments addressed this possibility by evaluating the correlation between c-FLI in the intermediate division of the NTS (iNTS) and 2 measures of conditioned fear: freezing and changes in mean arterial pressure (MAP) and heart rate (HR). Exposure to the taste conditioned stimulus (CS) resulted in a marked induction of c-FLI in the iNTS, whereas exposure to a fear CS did not. Further, exposure to a taste CS did not selectively lead to increases in MAP or HR. Results suggest that induction of c-FLI in the iNTS may reflect the activation of a cell population whose function is unique to the CTA paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
117.
We report on the physical characteristics of Aitken nuclei and their relation to air mass type at Ross Island, Antarctica. The size distribution spectrum of the particles was derived with a diffusion battery and non-linear mathematical inversion and is considered to be quite accurate over the particle diameter range 0.01 < d < 0.2 μm.

The Aitken nuclei concentration, no, decreased at Ross Island by about an order of magnitude from summer (no = 600 cm−3) to winter (no = 100 cm−3). Particle size varied with air mass type: Maritime polar air masses had a geometric mean particle diameter dg = 0.011 μm, while continental Antarctic, cA, air masses possessed somewhat smaller particles (i.e. dg 0.005 μm). The anomalously small particles associated with cA air suggests the presence of an upper tropospheric or partly stratospheric origin of nuclei perhaps associated with mixing formed by breaking waves over the Ellsworth Range in Marie Byrd Land.  相似文献   

118.
Stepping motors provide precise digital control of speed, without tachometer feedback, and have no brushes to wear. This makes them useful in feedback control systems. However, the stepping motor's natural resonance and its requirement for limited acceleration can cause sustained vibrations and overshoots. Modulating a stream of stepping pulses at twice the resonance frequency with special sequences of ones and zeros overcomes resonance problems. Using a piecewise linear function relating the target stepping rate to the position error prevents saturated overshoots. This function can be generated automatically from more basic parameters of the control system.  相似文献   
119.
Spiral and Scarpa's (vestibular) ganglia of female C57BL/6 mice, ranging in age from 1.5 to 32 months, were examined by light and electron microscopy. The spiral ganglia of C57BL/6 mice undergo sweeping neuronal losses. Based on cytological characteristics that repeat themselves in both young and old mice, we divided perikaryal demyelination and degeneration of spiral ganglia into four arbitary stages: (1) incipient demyelination, myelin sheaths begin to loosen and unravel; (2) contact, the partially demyelinated perikarya abut as the extracellular matrix disappear; (3) clumping, clusters of naked perikarya clump together, cytoplasmic processes surround the exterior of the clump; and (4) resorption, the clumps gradually disintegrate, leaving at completion large, fluid-filled spaces and few cellular remnants. In Scarpa's ganglia, a small number of neurons demyelinate and clump, but none degenerate or undergo resorption.  相似文献   
120.
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