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The African Humid Period (AHP), spanning ∼15-5 ka, was characterize across East Africa by increased precipitation. Wetter climate conditions created environments favorable to human occupation in what are today harsh, resource-limited places to inhabit. The Turkana Basin is a striking example of this. Throughout the AHP, lake levels intermittently rose ∼100 m establishing hydrologic connectivity from Lake Turkana into the Nile drainage system via an outlet to the northwest. This study presents new, high-resolution data from West Turkana outcrops of the Late Pleistocene/Holocene Galana Boi Formation. This research complements existing lake-level curves and allows for landscape reconstruction through lateral facies associations. The Kabua Gorge area contains both well-exposed stratigraphic sections and multiple archaeological sites to the north and west of the outcrops. This creates the opportunity to tie the archaeology closely to paleoenvironmental reconstructions from the geological record . The depositional environment is characterized by a dynamic fluctuating lake margin, consisting of at least four phases of inundation. Highstand Phase 4 is distinct within the Kabua Gorge sequence because it is comprised of black clay containing 2–10% total organic carbon , pedogenic overprinting, pedogenic carbonate nodules , and a diverse molluscan fauna. Deposition of this unit is indicative of an organic-rich, reducing lacustrine environment that was subsequently overprinted by pedogenesis . This unit grades laterally basinward from organic-rich paleosols to lacustrine silts characterized by abundant freshwater diatom taxa. By coupling sedimentology , diatom assemblage data, δ 13C and δ18 O isotope geochemistry of pedogenic carbonates, and a radiocarbon chronology for the area, the paleoenvironment of Kabua Gorge is interpreted as a shallow marshy embayment connected to the main body of a freshwater Lake Turkana. The landscape is a highly dynamic one, varying on a scale of 100s of meters. Sediments were deposited during periods of inundation and then pedogenically modified during brief periods of subaerial exposure to form Vertisols . Archaeological sites in the early part of the AHP at Kabua Gorge are closely associated in age with lacustrine highstands. Hence, we propose that the lagoonal marsh environment of Phase 4 would likewise have been a resource-rich area for human occupation during the AHP. Potential resources drawing humans to the area include access to fresh water and fishing grounds. Ultimately, understanding the paleoenvironmental dynamics at Kabua Gorge provides a window into the broader ecosystems in which humans culturally evolved from the Late Pleistocene to present.

A randomized, double-masked, placebo-controlled multicenter study was conducted for 6 weeks in 12 centers to evaluate the efficacy and safety of cromolyn sodium 4% ophthalmic solution (Opticrom) for the treatment of active bilateral vernal conjunctivitis. Objective clinical signs were graded weekly by an ophthalmologist while patients kept a daily record of the severity of their symptoms. Sixty-five patients completed the study; 35 received cromolyn sodium and 30 were treated with a matching placebo (the drug vehicle). Statistically significant differences in favor of cromolyn sodium treatment were found for conjunctival injection, limbal injection, limbal edema, tearing, and symptoms summary score. There were few side effects (usually mild stinging and burning which did not require drug stoppage). Only one patient required drug discontinuation for possible drug- or vehicle-related side effects. Cromolyn sodium was found to be significantly more effective than placebo in treating the signs and symptoms of vernal keratoconjunctivitis (VKC). When results were stratified in terms of the atopic status of the patient, it was clear that the allergic patients responded better to cromolyn sodium than did those in whom allergic (IgE-mediated) factors appeared unimportant in the disease process.

The technique of electron spectroscopy for chemical analysis (ESCA) is used to obtain rapid, nondestructive elemental analyses of selected lunar samples, and the chemical shift of the Fe(2p) line in lunar materials is found characteristic of iron in the Fe(2+) state. A difference in binding energy of approximately 0.5 eV is observed between the 0(1s) levels of the terrestrial minerals fayalite and quartz, and effects due to surface oxidation and absorption are also observed in terrestrial materials. The new ESCA technique is based on energy analysis at high resolution of electrons emitted from the surface of a sample on irradiation with X rays and is valuable for the study of the electronic structure of atoms and molecules.