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K M Groom

Publications and source records attributed to K M Groom.

5 recordsLinked to original sources

A prospective randomised controlled trial of the Kiwi Omnicup versus conventional ventouse cups for vacuum-assisted vaginal delivery.

OBJECTIVE: To evaluate the performance and safety of the Kiwi Omnicup and compare it to conventional vacuum cups in routine clinical practice. DESIGN: A randomised controlled trial of the Kiwi Omnicup versus conventional vacuum cups. SETTING: Queen Charlotte's and Chelsea Hospital, a tertiary referral hospital in London from April 2001 to March 2004. POPULATION: Women requiring assisted vaginal delivery by ventouse. METHODS: Women were randomised to the Kiwi Omnicup (n=206) or conventional vacuum cups (n=198). Data regarding maternal demographics, labour, mode of delivery and maternal and neonatal outcome were collected. MAIN OUTCOME MEASURES: Failure of delivery with instrument of first choice. RESULTS: The Kiwi Omnicup was less successful at delivery with instrument of first choice than the conventional ventouse, failure rate 30.1 versus 19.2% (RR 1.58; 95% CI 1.10-2.24). It was associated with a greater number of cup detachments (mean 0.68 compared with 0.28, with 44% compared with 18% having at least one detachment [P<0.0001]). There was no difference in the incidence of severe maternal trauma, and there were no cases of serious neonatal injury. CONCLUSIONS: The Kiwi Omnicup is less successful than conventional ventouse in achieving vaginal delivery, but its safety profile is comparable.

Adult↗

Dynamics of coherent and incoherent spin polarizations in ensembles of quantum dots.

The temperature dependence of spin coherence in InGaAs quantum dots is obtained from quantum beats observed in polarization-resolved pump-probe experiments. Within the same sample we clearly distinguish between coherent spin dynamics leading to quantum beats and incoherent long-lived spin-memory effects. Analysis of the coherent data using a theoretical model reveals approximately 10 times greater stability of the spin coherence at high temperature compared to that found previously for exciton states in four-wave-mixing experiments by Borri et al. [Phys. Rev. Lett. 87, 157401 (2001)]]. The data on incoherent polarization reveal a new form of spin memory based on charged quantum dots.

Journal Article↗