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Best management practices (BMPs) are widely promoted in agricultural watersheds as a means of improving water quality and ameliorating altered hydrology. We used a paired watershed approach to evaluate whether focused outreach could increase BMP implementation rates and whether BMPs could induce watershed-scale (4000 ha) changes in nutrients, suspended sediment concentrations, or hydrology in an agricultural watershed in central Illinois. Land use was >90% row crop agriculture with extensive subsurface tile drainage. Outreach successfully increased BMP implementation rates for grassed waterways, stream buffers, and strip-tillage within the treatment watershed, which are designed to reduce surface runoff and soil erosion. No significant changes in nitrate-nitrogen (NO-N), total phosphorus (TP), dissolved reactive phosphorus, total suspended sediment (TSS), or hydrology were observed after implementation of these BMPs over 7 yr of monitoring. Annual NO-N export (39-299 Mg) in the two watersheds was equally exported during baseflow and stormflow. Mean annual TP export was similar between the watersheds (3.8 Mg) and was greater for TSS in the treatment (1626 ± 497 Mg) than in the reference (940 ± 327 Mg) watershed. Export of TP and TSS was primarily due to stormflow (>85%). Results suggest that the BMPs established during this study were not adequate to override nutrient export from subsurface drainage tiles. Conservation planning in tile-drained agricultural watersheds will require a combination of surface-water BMPs and conservation practices that intercept and retain subsurface agricultural runoff. Our study emphasizes the need to measure conservation outcomes and not just implementation rates of conservation practices.

Use of eastern gamagrass (Tripsacum dactyloides L.) for grazing or cut forage has been partially limited because of indeterminate inflorescence development combined with low seed yields and high seed costs caused by high seed shattering. This study was conducted to observe the influence of N rate and defoliation on inflorescence appearance, seed loss, and viability of harvested seed in two cultivars of eastern gamagrass at Boone, IA, in 2000 and 2001. Treatments included application of N at 0, 56, 112, 224 kg ha - 1 and spring, fall, and no defoliation. Cultivar had the greatest influence on seed yield. 'Pete' produced greater total numbers of terminal and lateral inflorescences and cupules than 'Iuka' in both years. Reductions in seed production occurred with spring defoliation in Iuka for the first year of the study and Pete during both years. In 2000, seed on lateral inflorescences was decreased 20% during the peak seed load. In 2001, seed yield for spring-defoliated plants of Pete was less than that of fall-defoliated plants, but not significantly different from nondefoliated plants. Addition of 56 kg ha - 1 N increased seed load in the second year of the study. Optimal harvest time occurred approximately 2 wk after terminal cupules began shattering. Seed harvested 1 wk earlier than this had 5 to 15 percentage points more immature seed. Seed yield was 13 to 20% less if harvests were taken 1 wk later than the optimal date.

Daphnia lumholtzi comprises a substantial component of the zooplankton community during mid- to late-summer in Lake Chautauqua, a floodplain lake along the Illinois River near Havana, Illinois. In order to quantify the utilization of D. lumholtzi by juvenile fishes, diet analyses were conducted for seven juvenile fish species collected from Lake Chautauqua during the 2001 annual drawdown period. Freshwater drum Aplodinotus grunniens and emerald shiner Notropis atherinoides demonstrated negative selectivity for D. lumholtzi relative to native zooplankton species whereas four species of fish (bluegill Lepomis macrochirus, white bass Morone chrysops, white crappie Pomoxis annularis and black crappie Pomoxis nigromaculatus) consumed substantial amounts of D. lumholtzi. Although selectivity values for D. lumholtzi varied among these fish species, positive selection for D. lumholtzi increased similarly among larger size classes of each fish species, and corresponded with ontogenetic shifts in diet. Mean body length of D. lumholtzi consumed by 20–69 mm LT juvenile fishes ranged from 0·75 to 0·99 mm with a calculated total length range of 2·0–2·6 mm. Results from this study provide evidence that high abundances of D. lumholtzi in mid- to late-summer provide an additional food source for several juvenile fish species during a time when abundances of large native cladoceran species (i.e. Daphnia) are low, and juvenile fishes are searching for larger prey associated with ontogenetic shifts from zooplankton to macroinvertebrates and fishes. Because zooplankton production is typically lower in rivers than in lakes, survivorship of juvenile fishes produced in floodplain lakes may be higher in riverine systems if they are not reliant on zooplankton as a primary food resource. Therefore, high abundances of D. lumholtzi may benefit juvenile fishes in managed floodplain lakes, such as Lake Chautauqua, by increasing growth and facilitating the transition from zooplanktivory to insectivory or piscivory.

SUMMARY 1. Growth, reproduction and life-history parameters were measured for three cladoceran species from a small south-eastern wetland, U.S.A. Simocephalus serrulatus, Diaphanosoma brachyurum and Scapholeberis mucronata juveniles were reared at temperatures between 10 and 25 °C on natural food resources. 2. Growth rate increased with temperature and decreased with individual size for all three species. Maximum somatic growth rate was higher for Simocephalus (49–72% day−1) and Diaphanosoma (21–91% day−1) than for Scapholeberis (11–45% day−1). Multiple regression equations were developed which predict temperature- and mass-specific growth rates for each species. 3. Scapholeberis egg production was positively related to temperature; however, maximum egg production occurred at intermediate temperatures for Simocephalus and Diaphanosoma. Mean cumulative egg production was higher for Scapholeberis (28–92 eggs per female) than for Simocephalus (18–25 eggs per female) and Diaphanosoma (1–41 eggs per female), and was related to differences in reproductive strategy and survival. 4. Survival was inversely related to temperature in most cases. For all three cladocerans, the intrinsic rate of increase (r) and net reproductive rate (R0) increased with temperature, whereas generation time (G) decreased. Greater egg production by Scapholeberis compared with the other two cladocerans was consistent with higher R0 values for Scapholeberis at any given temperature. Although r was very similar among species, G was typically longer for Scapholeberis than for Simocephalus and Diaphanosoma. 5. This analysis provides basic information about the population parameters of these coexisting wetland species, and the growth rate models can be applied to field data to determine production dynamics.

BACKGROUND Although it is used widely, the value of gallium imaging in managing Hodgkin's disease remains unclear. METHODS A retrospective review of gallium imaging and treatment outcome in 60 patients with Hodgkin's disease treated between January 1990 and July 1995 was conducted. The minimum follow-up was 1 year. RESULTS Based on gallium imaging, 46 patients were in complete remission (CR) after initial treatment, 10 were in partial remission (PR), and 4 had persistent or progressive disease (NR). Ten of 29 patients (34%) with gallium CR after chemotherapy subsequently recurred, compared with no recurrences in 17 patients receiving initial radiotherapy or combined chemoradiation. Eight of ten patients received further therapy after gallium PR, and nine patients remained disease free at last follow-up. Survival did not differ in patients achieving a gallium CR or PR. CONCLUSIONS Gallium-67 imaging may help confirm the presence of active Hodgkin's disease, but was unreliable in defining disease remission after chemotherapy in this study population. Patients with a gallium PR may still have a good prognosis after additional therapy. Cancer 1998;82:754-9. ©; 1998 American Cancer Society.

BACKGROUND Iproplatin (cis-dichloro-transdihydroxybis-isopropylamine platinum IV; CHIP) is a second generation cisplatin derivative that was developed to retain the antineoplastic effect of cisplatin with fewer toxic effects. Early clinical studies showed moderate activity in some neoplasms, with disappointing results in tumors of the lower gastrointestinal tract. Myelosuppression was the dose-limiting toxic effect in the acute setting. METHODS The authors report a patient with metastatic adenocarcinoma of the colon who received long-term therapy with CHIP. RESULTS The patient achieved complete remission of disease after prolonged treatment with CHIP. The patient subsequently had a myelodysplastic syndrome that rapidly transformed to acute myelogenous leukemia. CONCLUSIONS Acute leukemia may represent a late complication of CHIP therapy.

A strong transannular Re-Re interaction and reactive metal-sulfur bonds characterize the title anion 1 (shown on the right without the two chelating S4-ligands). This surprising result explained by the existence of molecular orbitials arising from Re 5d and S 3p functions of similar energy are not only Re-Re bonding but also markedly delocalized. These findings underline the importance of the role of the metal center, especially in catalytically active metal sulfides.

The electronic structure of the triangular thio cluster [Mo3S13]2− has been studied by electronic absorption and XP spectra and is discussed in terms of SCF-Xα-SW calculations. The synthesis and crystal structure of (Ph4As)2[Mo3S13]·2CH3CN, which is soluble in organic solvents, are reported together with a refinement of the crystal structure of (NH4)2[Mo3S13]·H2O. Untersuchungen am dreikernigen Cluster [Mo3S13]2−: Elektronenstruktur (Xα-Rechnungen, Rontgenphotoelektronenspektren), Kristallstruktur von (Ph4As)2[Mo3S13] · 2CH3CN und Verfeinerung der Kristallstruktur von (NH4)2[Mo3S13] · H2O Die Elektronenstruktur des dreikernigen Clusters [Mo3S13]2− wird anhand von Elektronenabsorptions- und Rontgenphotoelektronen-Spektren untersucht und im Rahmen von SCF-Xα-SW-Rechnungen diskutiert. Die Herstellung und die vollstandige Kristallstruktur des in organischen Losungsmitteln loslichen (Ph4As)2[Mo3S13] · 2CH3CN wird mitgeteilt, zusammen mit einer Verfeinerung der Kristallstruktur von (NH4)2[Mo3S13] · H2O.