An iron-N-heterocyclic carbene catalyst generated from an iron(III) salt, an imidazolinium salt, and a Grignard reagent promotes alkylation and alkenylation reactions at the indole C2-position with vinylarenes and internal alkynes, respectively, via imine-directed C-H activation. The former reaction affords 1,1-diarylalkane derivatives with exclusive regioselectivity. Deuterium-labeling experiments suggest that these reactions involve oxidative addition of the C-H bond to the iron center, insertion of the unsaturated bond into the Fe-H bond, and C-C reductive elimination.
Bilirubin and its photoisomers in the biological fluids of a hyperbilirubinaemic newborn infant before and during phototherapy were analyzed by a recently improved HPLC method. In the serum, the percentages of (EZ)- and (ZE)-bilirubin in the total bilirubin concentration before phototherapy were approximately 10% and on average increased over 1.5-fold at 2 h after initiation of phototherapy. The percentage of the (EZ)-cyclobilirubin in the serum bilirubin was under 1%. In the bile, the mean concentration of (ZZ)-bilirubin, derived mainly from (ZE)-bilirubin, nearly tripled during phototherapy. The (EZ)-cyclobilirubin concentration in the bile was very low before phototherapy, increased nearly ten-fold at 3 h after initiation of phototherapy, and was 5- to 6-fold as high as that of (ZZ)-bilirubin. In the urine, upon exposure to light, the urinary concentration of (EZ)-cyclobilirubin is apparently equivalent to half of the biliary concentration of (ZZ)-bilirubin and one-fifth of that of (EZ)-cyclobilirubin. It was concluded that during phototherapy of neonatal hyperbilirubinaemia the structural photoisomer [(EZ)-cyclobilirubin] predominates considerably over the geometric photoisomer [(ZE)-bilirubin].
In this tutorial, the utility of a fuzzy system is demonstrated by providing a broad overview, emphasizing analog mode hardware, along with a discussion of the author's original work. First, the difference between deterministic words and fuzzy words is explained as well as fuzzy logic. The description of the system using mathematical equations, linguistic rules, or parameter distributions (e.g., neural networks) is discussed. Fuzzy inference and defuzzification algorithms are presented, and their hardware implementation is discussed. The fuzzy logic controller was used to stabilize a glass with wine balanced on a finger and a mouse moving around a plate on the tip of an inverted pendulum.
SUMMARYPurpose: Focal brain cooling is effective for suppression of epileptic seizures, but it is unclear if seizures can be suppressed without a substantial influence on normal neurologic function. To address the issue, a thermoelectrically driven cooling system was developed and applied in freemoving rat models of focal seizure and epilepsy. Methods: Focal seizures limited to the unilateral forelimb were induced by local application of a penicillin G solution or cobalt powder to the unilateral sensorimotor cortex. A proportional integration and differentiation (PID)-controlled, thermoelectrically driven cooling device (weight of 11 g) and bipolar electrodes were chronically implanted on the eloquent area (on the epileptic focus) and the effects of cooling (20, 15, and 10°C) on electrocorticography, seizure frequency, and neurologic changes were investigated. Key Findings: Cooling was associated with a distinct reduction of the epileptic discharges. In both models, cooling of epileptic foci significantly improved both seizure frequency and neurologic functions from 20°C down to 15°C. Cooling to 10°C also suppressed seizures, but with no further improvement in neurologic function. Subsequent investigation of sensorimotor function revealed significant deterioration in foot-fault tests and the receptive field size at 15°C. Significance: Despite the beneficial effects in ictal rats, sensorimotor functions deteriorated at 15°C, thereby suggesting a lower limit for the therapeutic temperature. These results provide important evidence of a therapeutic effect of temperatures from 20 to 15°C using an implantable, hypothermal device for focal epilepsy.
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