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This study investigated pretreatment variables associated with depression severity in adolescents following maintenance treatment for major depressive disorder (MDD). Data was derived from the Treatment for Adolescents with Depression Study (TADS). Participants received one of three treatments: cognitive behavioral therapy (CBT), fluoxetine (FLX), or combined CBT and fluoxetine (COMB). Participants received 12 weeks of acute treatment, 6 weeks of consolidation treatment, and 18 weeks of maintenance treatment (N = 327, M age = 14.62 yrs). Outcome was measured by the Children’s Depression Rating Scale-Revised. Results showed adolescents with shorter depressive episodes, better global functioning, less suicidal ideation, better health/social functioning, and greater expectancy of positive treatment response were more likely to have lower depression severity following 36 weeks of treatment, regardless of modality. Adolescents with lower initial depression demonstrated lower depression severity if treated with CBT. FLX was more effective in reducing depression severity in adolescents with severe baseline depression than for those with mild or moderate depression. Adolescents with higher family incomes were more likely to have lower depression severity if they received CBT only. In conclusion, adolescents with shorter depressive episodes, better health, social, and global functioning, less suicidal ideation, and greater expectancy for treatment at baseline respond equally well to CBT, fluoxetine, and combined treatment. Adolescents who are more severely depressed at baseline may have a better treatment response if they are treated with FLX; whereas adolescents of higher income are more likely to have a better response if they receive CBT only.

Biological herbicides will assume greater importance for weed control as the number of chemicals registered for use decreases. Two promising fungi pathogenic on Datura stramonium and Cassia obtusifolia are, respectively, Alternaria crassa and Alternaria cassiae. In order to develop technologies for the efficient production of spore inocula in submerged liquid culture, we studied the effect of volatile factors which influenced sporulation on solid media. Sporulation was quantified on Richard's V8 agar under individual and joint variation of carbon dioxide (CO2) and relative humidity (RH). Sporulation of both fungi was suppressed when the two factors increased but not when CO2 was absorbed and RH remained high. Incubation of cultures in a CO2 controlled cabinet with RH constant indicated that CO2 was the suppressant.

During development, the precursors for eggs and sperm — the germ cells — migrate to the gonads to mature. But what attracts them there? Results from a fruitfly screen indicate that one component in this pathway is a gene called columbus, which encodes HMG-CoA reductase. In humans, this enzyme is involved in cholesterol biosynthesis, raising the intriguing possibility that the attractant may be a lipid.

We conducted a study of the relationship between changes in photosynthetic pigment content and water depth in Great Harbor near Woods Hole, Massachusetts, USA, on the green algae Ulva lactuca and Codium fragile and the red algae Porphyra umbilicalis and Chondrus crispus. A calibrated underwater photometer equipped with spectral band filters measured light attenuation by the water column. The depth required for a 10-fold diminution of photon flux was 3.6, 5.3, 6.0 and 6.0 m for red, blue, yellow and green light, respectively. Seaweeds were attached to vertically buoyed lines and left to adapt for 7 days; then, with their positions reversed, they were allowed to readapt for 7 days. All species showed greater photosynthetic pigment content with increased depth. Further, the ratio of phycobiliproteins and chlorophyll b to chlorophyll a increased with depth. Changes in pigment content were reversible and occurred in the absence of cell division. There was a net loss of pigments near the surface (high irradiance), and subsequent synthesis when seaweeds were transferred to a position deep in the water column (low irradiance). In contrast, seaweeds which were found in intertidal habitats changed only their pigment concentration, and not pigment ratio, a phenomena analogous to higher plant sun and shade adaptation. Therefore, seaweeds modify their photon-gathering photosynthetic antennae to ambient light fields in the water column by both intensity adaptation and complementary chromatic adaptation.

The distribution of cyanobacteria in the surface waters of the North Sea was measured during July 1987. Numbers of cyanobacteria ranged from 2.5x106 to 1.7x108 cells 1-1. In the majority of stations, cyanobacterial numbers were highest in the near-surface water and a subsurface maximum was found at only one station. The distribution of 14C among the end-products of photosynthesis was determined for picoplankton ( 1 μm throughout the North Sea. The majority of label was found in the protein fraction of both picoplankton and >1 μm phytoplankton; incorporation into lipids and polysaccharides plus nucleic acids was much lower. We interpret the large incorporation into protein to be a consequence of nutrient limitation of these natural assemblages. Photosynthetic parameters of the two size fractions were also determined. Assimilation number (PmB) and initial slope αβ were greater for the picoplankton fraction than for phytoplankton >1 μm but there was no evidence of significant photoinhibition of either fraction at irradiances up to 1 000 μE m-2 s-1.

Segmentation of the Drosophila embryo requires expression of the pair-rule genes, mutations of which cause reiterated deletions in alternate segments along the antero-posterior body axis. We find that transcripts of one such gene, hairy, accumulate in eight distinct regions of the early embryo. This pattern of expression is compared with that of another pair-rule gene, fushi tarazu, and its dependence on maternally expressed genes is described.

The first hint of segmentation in the Drosophila embryo is the appearance of shallow transverse grooves that divide the main part of the germ band into 14 uniform domains1. These grooves are conspicuous in the 5–7-h-old embryo when viewed in the scanning electron microscope2 and can also be seen in longitudinal sections. Since their discovery in 1950, the domains delineated by the grooves haye been thought to be segments1,2, but now several lines of evidence suggest that they are ‘parasegments’—units consisting of a posterior compartment3 of one segment and an anterior compartment of the next4,5. If this is the case, the posterior compartments would lie in the anterior parts, of the domains delineated by the grooves. By using the engrailed gene product as a marker, we have now mapped the posterior compartments and report here that they are indeed located in the anterior quarter of the domains and that their anterior borders coincide with the grooves, establishing that the domains are parasegments.