Foreword to the AfCA collection: celebrating work published by African researchers in IUCr journals.

This virtual collection is a celebration. It is a celebration of crystallography in Africa, and a celebration of the international crystallography community. It commemorates the founding of the African Crystallographic Association (AfCA), which was accepted as the newest Regional Associate of the International Union of Crystallography (IUCr) in 2023, the year of the 75th anniversary of the first IUCr Congress and General Assembly.

A Phase 1 Assessment of the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of (2R,6R)-Hydroxynorketamine in Healthy Volunteers.

(R,S)-Ketamine (ketamine) is a dissociative anesthetic that also possesses analgesic and antidepressant activity. Undesirable dissociative side effects and misuse potential limit expanded use of ketamine in several mental health disorders despite promising clinical activity and intensifying medical need. (2R,6R)-Hydroxynorketamine (RR-HNK) is a metabolite of ketamine that lacks anesthetic and dissociative activity but maintains antidepressant and analgesic activity in multiple preclinical models.

Chemistry and crystal engineering.

Recent studies published in the Chemistry and crystal engineering section of IUCrJ emphasize developments both in methodology and techniques as well as the diverse range of classes of compounds being studied and of problems being tackled.

Recruitment Strategies in the Integration of Mobile Health Into Sickle Cell Disease Care to Increase Hydroxyurea Utilization Study (meSH): Multicenter Survey Study.

Background: Hydroxyurea is an evidence-based disease-modifying therapy for sickle cell disease (SCD) but is underutilized. The Integration of Mobile Health into Sickle Cell Disease Care to Increase Hydroxyurea Utilization (meSH) multicenter study leveraged mHealth to deliver targeted interventions to patients and providers. SCD studies often underenroll; and recruitment strategies in the SCD population are not widely studied.

Using randomized controlled trials to ask questions regarding developmental psychopathology: A tribute to Dante Cicchetti.

Dante Cicchetti, the architect of developmental psychopathology, has influenced so many of us in profound ways. One of his many contributions was in demonstrating the power of randomized controlled trials (RCTs) to study the effects of Child-Parent Psychotherapy (CPP). These RCTs have shed light on causal mechanisms in development.