he Internet of Things (IoT) is a continually growing, massive communication network composed of wireless transceivers and sensors 1-3. On-chip transformers are important elements in IoT devices, with applications in energy converters,... more
he Internet of Things (IoT) is a continually growing, massive communication network composed of wireless transceivers and sensors 1-3. On-chip transformers are important elements in IoT devices, with applications in energy converters, fluxgate magnetometer sensors, wireless pressure sensors, and bioparticle detectors in microfluids, as well as traditional uses in wireless transmitters for signal amplification, impedance matching, d.c. signal isolation and low-noise feedback 4-7 .
Background: E-cigarettes, nicotine transdermal patches, and nicotine chewing gum are occasionally used as cigarette replacements by patients, but it is unknown if their use is a safe alternative to smoking in the perioperative period.... more
Background: E-cigarettes, nicotine transdermal patches, and nicotine chewing gum are occasionally used as cigarette replacements by patients, but it is unknown if their use is a safe alternative to smoking in the perioperative period. Methods: All patients undergoing major surgery at a single outpatient ambulatory surgery center for a 5-year period were tested for urine cotinine, a nicotine metabolite, the day of surgery. Patients were divided into 4 groups: never smoked (group A), quit smoking with negative urine test (group B), continued to smoke (group C), and quit smoking with positive urine test (group D). Statistical significance of complications among groups was tested using right tailed chi-square test and point biserial correlation coefficient calculations. To control for confounding factors, age and BMI of each group were compared using unequal sample size and variance t tests. Results: Four hundred seventy patients were included in the study. Patient count in each group was group A n = 380, group B n = 48, group C n = 32, and group D n = 10. Complication frequency was as follows D > C > A > B. Statistically significant differences were observed between D + C (cotinine positive) and A + B (cotinine negative) P = 0.0001 and between D (nicotine replacement) and B (nicotine abstinence) P = 0.00026. There was neither statistical difference between groups A and B, nor C and D. Conclusions: Nicotine replacement carries similar risks as continued smoking and is not as safe as abstinence in the perioperative period in plastic surgery patients. Importantly, patients who stopped smoking for the surgery had equivalent risk for postoperative complications as patients who had never smoked.
Directing neurons to form predetermined circuits with the intention of treating neurological disorders and neurodegenerative diseases is a fundamental goal and current challenge in neuroengineering. Until recently, only neuronal... more
Directing neurons to form predetermined circuits with the intention of treating neurological disorders and neurodegenerative diseases is a fundamental goal and current challenge in neuroengineering. Until recently, only neuronal aggregates were studied and characterized in culture, which can limit information gathered to populations of cells. In this study, we use a substrate constructed of arrays of straininduced self-rolled-up membrane 3D architectures. This results in changes in the neuronal architecture and altered growth dynamics of neurites. Hippocampal neurons from postnatal rats were cultured at low confluency (∼250 cells mm −2) on an array of transparent rolled-up microtubes (μ-tubes; 4−5 μm diameter) of varying topographical arrangements. Neurite growth on the μ-tubes was characterized and compared to controls in order to establish a baseline for alignment imposed by the topography. Compared to control substrates, neurites are significantly more aligned toward the 0°reference on the μ-tube array. Pitch (20−60 and 100 μm) and μ-tube length (30−80 μm) of array elements were also varied to investigate their impact on neurite alignment. We found that alignment was improved by the gradient pitch arrangement and with longer μ-tubes. Application of this technology will enhance the ability to construct intentional neural circuits through array design and manipulation of individual neurons and can be adapted to address challenges in neural repair, reinnervation, and neuroregeneration.
A new approach to atomic layer etching (ALE) has been demonstrated, and its application to 4H-SiC is reported here. By pulsing only the DC bias for an Ar/Cl2 inductively coupled plasma-reactive ion etching system, the etch cycle duration... more
A new approach to atomic layer etching (ALE) has been demonstrated, and its application to 4H-SiC is reported here. By pulsing only the DC bias for an Ar/Cl2 inductively coupled plasma-reactive ion etching system, the etch cycle duration is reduced by more than an order of magnitude relative to conventional ALE processes. Gas flows are not changed throughout the ALE process. With this process protocol, we achieved an etch rate of 2.48±0.09 Å/cycle with 6 s cycles, an RMS surface roughness (Rq) of 0.83±0.08 Å, and an ALE synergy value of S = 99%. The parameters explored within this ALE process demonstrate effective subangstrom smoothening of 4H-SiC surfaces and is well-suited for a variety of classical and quantum device nanofabrication.
with an error in Eq. (1). Equation (1) is correct below. H 2 O 2 þ 4H þ þ 2e À ðSiÞ À ! catalyst 2H 2 O þ 2h þ Si ð Þ þ H 2ðgÞ: (1) All online versions of this article were corrected on 16 February 2023. AIP Publishing apologizes for this... more
with an error in Eq. (1). Equation (1) is correct below. H 2 O 2 þ 4H þ þ 2e À ðSiÞ À ! catalyst 2H 2 O þ 2h þ Si ð Þ þ H 2ðgÞ: (1) All online versions of this article were corrected on 16 February 2023. AIP Publishing apologizes for this error.
Fine-grained understanding of dynamics in cortical networks is crucial in unpacking brain function. Here, we introduce a novel analytical method to characterize the dynamic interaction between distant brain regions, and apply it to data... more
Fine-grained understanding of dynamics in cortical networks is crucial in unpacking brain function. Here, we introduce a novel analytical method to characterize the dynamic interaction between distant brain regions, and apply it to data from the Human Connectome Project.Resting-state fMRI results in time series recordings of the activity of different brain regions, which are aperiodic and lacking a base frequency. Cyclicity Analysis, a novel technique robust with respect to time-reparametrizations, is effective in recovering temporal ordering of such time series along a circular trajectory without assuming any time-scale. Our analysis detected slow cortical waves of activity propagating across the brain with consistent lead-lag relationships between specific brain regions. We also observed short bursts of task-modulated strong temporal ordering that dominate overall lead-lag relationships between pairs of regions in the brain. Our results suggest the possible role played by slow wav...
Ping Pong, or table tennis, is a very popular sport in Asia. Usually, two or four players are involved in the game that hit a ball back and forth across a table divided by a net. Many people love playing Ping Pong, but not everyone can... more
Ping Pong, or table tennis, is a very popular sport in Asia. Usually, two or four players are involved in the game that hit a ball back and forth across a table divided by a net. Many people love playing Ping Pong, but not everyone can find a mate to play within any time, which usually depends on their friends' schedules. In order to solve this problem, a Ping Pong machine will be designed using a robot arm to enable single-player mode for this sport, so a person can play Ping Pong. Due to time constraints, a basket will be used instead of a racket to collect the ball. The robot arm can successfully reach and collect the Ping Pong ball with an accuracy of 73.3%. The knowledge of inverse kinematics and supervised learning is applied in this project. Further improvement will emphasize hitting the Ping Pong ball back to the player with a racket.
