ABSTRACT
Studies of ecosystem processes on the Jornada Experimental Range in southern New Mexico suggest that longterm grazing of semiarid grasslands leads to an increase in the spatial and temporal heterogeneity of water, nitrogen, and other soil resources. Heterogeneity of soil resources promotes invasion by desert shrubs, which leads to a further localization of soil resources under shrub canopies. In the barren area between shrubs, soil fertility is lost by erosion and gaseous emissions. This positive feedback leads to the desertification of formerly productive land in southern New Mexico and in other regions, such as the Sahel. Future desertification is likely to be exacerbated by global climate warming and to cause significant changes in global biogeochemical cycles.
ABSTRACT
Ninety-three female patients with post-cesarean endometritis, post-hysterectomy pelvic cellulitis, and other miscellaneous moderately severe pelvic soft-tissue infections were treated in a randomized fashion with either ticarcillin plus clavulanic acid or cefoxitin. Of the 47 patients treated with ticarcillin plus clavulanic acid, 38 had clinical cures, four showed improvement, therapy failed in three, and two were nonevaluable, for a failure rate of 6.7 percent. Of the 46 patients treated with cefoxitin, 33 had clinical cures, five showed improvement, therapy failed in seven, and one was nonevaluable, for a failure rate of 15.6 percent. Bacteriologically, the addition of clavulanic acid to ticarcillin was found to broaden the antibacterial spectrum to include some Escherichia coli, most Klebsiella, many coagulase-negative staphylococci, and all isolates of Staphylococcus aureus. Adverse reactions were few, with only one patient having therapy with cefoxitin discontinued because of side effects. It is concluded that ticarcillin plus clavulanic acid is quite suitable for antibiotic therapy of female pelvic soft-tissue infection, based on the (expanded) coverage of both aerobic and anaerobic bacterial species.
Subject(s)
Bacterial Infections/drug therapy , Cefoxitin/therapeutic use , Clavulanic Acids/administration & dosage , Pelvic Inflammatory Disease/drug therapy , Penicillins/administration & dosage , Ticarcillin/administration & dosage , Adolescent , Adult , Cellulitis/drug therapy , Clavulanic Acid , Drug Combinations , Endometritis/drug therapy , Female , Humans , Middle AgedABSTRACT
Data from the US/IBP Desert Biome validation studies indicate that above-ground production and biomass allocated to reproduction in Larrea tridentata vary from one year to another depending upon the timing and extent of soil-moisture availability. In an attempt to verify these observations and determine to what extent water availability can affect total aboveground production and reproductive allocation in this widely distributed warm desert shrub, a series of soil-moisture augmentation experiments were conducted. High levels of soil moisture had a greater effect on reproductive allocation than on total above-ground production. Enhanced soil moisture during the period of active growth increased total above-ground production and reduced the percentage of biomass allocated to reproduction. Enhanced soil moisture during the normal periods of little or no growth did not increase total above-ground production.
