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T Howard

Publications and source records attributed to T Howard.

90 records · Page 5Linked to original sources
PubMed1972

Home care service.

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Home Care Services↗
PubMedDate not supplied

Characterization of iron, manganese, and copper synthetic hydroxyapatites by electron paramagnetic resonance spectroscopy.

The incorporation of micronutrients (e.g., Fe, Mn, Cu) into synthetic hydroxyapatite (SHA) is proposed for slow release of these nutrients to crops in NASA's Advanced Life Support (ALS) program for long-duration space missions. Separate Fe3+ (Fe-SHA), Mn2+ (Mn-SHA), and Cu2+ (Cu-SHA) containing SHA materials were synthesized by a precipitation method. Electron paramagnetic resonance (EPR) spectroscopy was used to determine the location of Fe3+, Mn2+, and Cu2+ ions in the SHA structure and to identify other Fe(3+)-, Mn(2+)-, and Cu(2+)-containing phases that formed during precipitation. The EPR parameters for Fe3+ (g=4.20 and 8.93) and for Mn2+ (g=2.01, A=9.4 mT, D=39.0 mT and E=10.5 mT) indicated that Fe3+ and Mn2+ possessed rhombic ion crystal fields within the SHA structure. The Cu2+ EPR parameters (g(z)=2.488, A(z)=5.2 mT) indicated that Cu2+ was coordinated to more than six oxygens. The rhombic environments of Fe3+ and Mn2+ along with the unique Cu2+ environment suggested that these metals substituted for the 7 or 9 coordinate Ca2+ in SHA. The EPR analyses also detected poorly crystalline metal oxyhydroxides or metal-phosphates associated with SHA. The Fe-, Mn-, and Cu-SHA materials are potential slow release sources of Fe, Mn, and Cu for ALS and terrestrial cropping systems.

Copper↗
PubMedDate not supplied

Neurologic improvement of patients with hepatic failure and coma during sorbent suspension dialysis.

Fifteen patients with acute deterioration of liver function, high serum ammonia, and an average coma level of 3.9 (of 4) were treated for 8-12 hrs daily with a system that uses the membranes of a cellulosic plate dialyzer to pump blood through a single access at 200-225 ml/min, and includes a sorbent suspension as dialysate. Neurologic status of the patients was declining before treatment, but significantly improved during each treatment and over the course of 1-12 (average, 4) treatments. Diastolic blood pressure and pulse rate normalized. For half the patients, treatment with the BioLogic-DT system served as a bridge to liver transplant or liver recovery.

Adult↗