Many achiral molecules can be made chiral by appropriate positioning of an isotope. Accurate detection of this type of chirality has remained elusive, and there is as yet no general method for detection of isotopically chiral species. Here, we present the first application of microwave three-wave mixing to isotopically chiral molecules, detecting enantiomeric excess in ( R/ S)-benzyl-α-D alcohol.
View Article and Find Full Text PDFPromise of rewards has been widely used in controlling preschoolers' behaviors. The current study investigated how the expectation of receiving an external reward may influence preschoolers' executive function. Four- to 5-year-old Singaporean children were randomly assigned to reward-informed and reward-uninformed conditions.
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November 1998
Increasing clinical experience with the selective serotonin reuptake inhibitors and tricyclic antidepressants make combination antidepressant therapy at times a reasonable alternative to single-agent therapy in primary care patients with depression. This article describes three cases that illustrate possible rationales for combination antidepressant therapy: reduced side effects, synergistic treatment effects, reduced treatment response time, prescriber familiarity, and clinical experience. The combination of selective serotonin reuptake inhibitors and tricyclic antidepressants may be useful in treating patients who experience intolerable side effects or who are resistant to therapy with a single antidepressant.
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