7,331 research outputs found
A new time-frequency method to reveal quantum dynamics of atomic hydrogen in intense laser pulses: Synchrosqueezing Transform
This study introduces a new adaptive time-frequency (TF) analysis technique,
synchrosqueezing transform (SST), to explore the dynamics of a laser-driven
hydrogen atom at an {\it ab initio} level, upon which we have demonstrated its
versatility as a new viable venue for further exploring quantum dynamics. For a
signal composed of oscillatory components which can be characterized by
instantaneous frequency, the SST enables rendering the decomposed signal based
on the phase information inherited in the linear TF representation with
mathematical support. Compared with the classical type TF methods, the SST
clearly depicts several intrinsic quantum dynamical processes such as selection
rules, AC Stark effects, and high harmonic generation
Delayed Airway Obstruction after Internal Jugular Venous Catheterization in a Patient with Anticoagulant Therapy
Delayed onset of neck hematoma following central venous catheterization without arterial puncture is uncommon. Herein, we present a patient who developed a delayed neck hematoma after repeated attempts at right internal jugular venous puncture and subsequent enoxaparin administration. Progressive airway obstruction occurred on the third day after surgery. Ultrasound examination revealed diffuse hematoma of the right neck, and fibreoptic examination of the airway revealed pharyngeal edema. After emergent surgical removal of the hematoma, the patient was extubated uneventfully
Reduced Ca2+ transport across sarcolemma but enhanced spontaneous activity in cardiomyocytes isolated from left atrium-pulmonary veins tissue of myopathic hamster
<p>Abstract</p> <p>Background</p> <p>Several lines of evidence point to a particularly important role of the left atrium (LA) in initiating and maintaining atrial fibrillation (AF). This role may be related to the location of pulmonary veins (PVs) in the LA. The aim of the present study was to investigate the action potential (AP) and ionic currents in LA-PV cardiomyocytes isolated from Bio14.6 myopathic Syrian hamsters (36-57 week-old) versus age-matched F1B healthy control hamsters.</p> <p>Methods and Results</p> <p>Whole-cell patch-clamp techniques were used to record AP in current-clamp mode and ionic currents in voltage-clamp mode. The results obtained show that in both healthy and myopathic LA-PV tissue spontaneously discharging cardiomyocytes can be found, but they are more numerous in myopathic (9/29) than in healthy hamsters (4/42, p < 0.05 by χ<sup>2 </sup>analysis). Myopathic myocytes have shorter AP duration (APD) with smaller I<sub>Ca,L </sub>and I<sub>NCX </sub>than the healthy control. The currents I<sub>TO</sub>, I<sub>K</sub>, I<sub>K1 </sub>and I<sub>Ca,T </sub>are not significantly different in myopathic versus healthy cells.</p> <p>Conclusions</p> <p>Our results indicate that in myopathic Syrian hamsters LA-PV cardiomyocytes are more prone to automatic rhythms. Also, they show altered electrophysiologic properties, which may be due to abnormal Ca<sup>2+ </sup>channels and may account for contractile dysfunction.</p
Multi-Contact Force-Sensing Guitar for Training and Therapy
Hand injuries from repetitive high-strain and physical overload can hamper or
even end a musician's career. To help musicians develop safer playing habits,
we developed a multiplecontact force-sensing array that can substitute as a
guitar fretboard. The system consists of 72 individual force sensing modules,
each containing a flexure and a photointerrupter that measures the
corresponding deflection when forces are applied. The system is capable of
measuring forces between 0-25 N applied anywhere within the first 12 frets at a
rate of 20 Hz with an average accuracy of 0.4 N and a resolution of 0.1 N.
Accompanied with a GUI, the resulting prototype was received positively as a
useful tool for learning and injury prevention by novice and expert musicians.Comment: IEEE Sensor Conference, 201
Mediation of Endogenous β-endorphin by Tetrandrine to Lower Plasma Glucose in Streptozotocin-induced Diabetic Rats
The role of β-endorphin in the plasma glucose-lowering action of tetrandrine in streptozotocin-induced diabetic rats (STZ-diabetic rats) was investigated. The plasma glucose concentration was assessed by the glucose oxidase method. The enzyme-linked immunosorbent assay was used to determine the plasma level of β-endorphin-like immunoreactivity (BER). The mRNA levels of glucose transporter subtype 4 (GLUT4) in soleus muscle and phosphoenolpyruvate carboxykinase (PEPCK) in the liver of STZ-diabetic rats were detected by Northern blotting analysis. The expressed protein of GLUT4 or PEPCK was characterized by Western blotting analysis. Tetrandrine dose-dependently increased plasma BER in a manner parallel to the decrease of plasma glucose in STZ-diabetic rats. Moreover, the plasma glucose-lowering effect of tetrandrine was inhibited by naloxone and naloxonazine at doses sufficient to block opioid μ-receptors. Further, tetrandrine failed to produce plasma glucose-lowering action in opioid μ-receptor knockout diabetic mice. Bilateral adrenalectomy eliminated the plasma glucose-lowering effect and plasma BER-elevating effect of tetrandrine in STZ-diabetic rats. Both effects were abolished by treatment with hexamethonium or pentolinium at doses sufficient to block nicotinic receptors. Tetrandrine enhanced BER release directly from the isolated adrenal medulla of STZ-diabetic rats and this action was abolished by the blockade of nicotinic receptors. Repeated intravenous administration of tetrandrine (1.0 mg/kg) to STZ-diabetic rats for 3 days resulted in an increase in the mRNA and protein levels of the GLUT4 in soleus muscle, in addition to the lowering of plasma glucose. Similar treatment with tetrandrine reversed the elevated mRNA and protein levels of PEPCK in the liver of STZ-diabetic rats. The obtained results suggest that tetrandrine may induce the activation of nicotinic receptors in adrenal medulla to enhance the secretion of β-endorphin, which could stimulate opioid μ-receptors to increase glucose utilization or/and reduce hepatic gluconeogenesis to lower plasma glucose levels in STZ-diabetic rats
Dose pre-hospital laryngeal mask airway use has a survival benefit in non-shockable cardiac arrest?
Background. Whether pre-hospital laryngeal mask airway (LMA) use poses a survival benefit and should be approved as
routine airway management in non-shockable cardiac arrest is of major concern. The present study examined the effectiveness
of LMA, in comparison to other pre-hospital airway management on individuals who have experienced non-shockable
cardiac arrest.
Methods. Adult patients who experienced non-shockable cardiac arrest with activation of the emergency medical service
(EMS) made up our study cohort in Taoyuan, Taiwan. The data were abstracted from EMS records and cardiac arrest registration
protocols.
Results. Among the 1912 enrolled patients, most received LMA insertion (72.4%), 108 (5.6%) bag-valve-mask (BVM) ventilation,
376 (19.7%) high-flow oxygen non-rebreather facemask, and only 44 (2.3%) received endotracheal tube intubation
(ETI). With regard to survival to discharge, no significant differences in prevalence were evident among the groups: 2.8% of
oxygen facial mask, 1.1% of BVM, 2.1% of LMA, and 4.5% of the ETI group survived to discharge (p = 0.314). In comparison
to oxygen facial mask use, different types of airway management remained unassociated with survival to discharge after
adjusting for variables by logistic regression analysis (BVM: 95% confidence interval [CI], 0.079 – 1.639 [p = 0.186]; LMA:
95% CI, 0.220–2.487 [p = 0.627]; ETI: 95% CI, 0.325–17.820 [p = 0.390]). The results of Hosmer-Lemeshow goodness-of-fit
test of logistic regression model revealed good calibration.
Conclusions. Pre-hospital LMA use was not associated with additional survival to discharge compared with facial oxygen
mask, BVM, or ETI following non-shockable cardiac arrest
Invited; CMOS inverters and circuits based on oxide thin-film transistors
Thin-film transistors (TFTs) based on oxide semiconductors have the advantage of promising carrier mobilities and good switching characteristics, and they can be fabricated by low-temperature and scalable processes. Complementary metal-oxide-semiconductor (CMOS) technology employing oxide TFTs shows great potential in enabling flexible electronics with versatile functionalities and low-static power consumptions. Here flexible CMOS inverters comprising p-type SnO TFTs and n-type ZnO or IGZO TFTs integrated in three different configurations were implemented and compared, as shown in Fig. 1. First, the planar inverter comprising bottom-gated SnO and ZnO TFTs with a geometric aspect ratio, (W/L)p / (W/L)n, of 5 had a static voltage gain of ~ 10 V/V at a supplied voltage (VDD) of 10 V [1]. However, the gain decreased as the inverter was subjected to a mechanical tensile strain, which may be ascribed to the degradation of TFT mobilities.
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