Scanning for PIT-tagged flatfish in a coastal area using a sledge equipped with an RFID antenna.

A radio frequency identification (RFID) antenna system, build into a sledge that can be towed behind a vessel like a trawl and thereby has the potential to detect the position of a passive inductor technology (PIT)-tagged fish in a wide variety of habitats, is presented. By scanning for hatchery-reared PIT-tagged turbot Psetta maxima released into a natural habitat, the performance of the system was compared to a standard juvenile trawl and results suggested that the efficiency of the sledge was five times that of the trawl, which in absolute values corresponds to 75% of P. maxima lying in the pathway of the sledge.

Sexual maturity cycle and spawning of Greenland halibut Reinhardtius hippoglossoides in the Davis Strait.

Female sexual maturation cycle and the main spawning time of Greenland halibut Reinhardtius hippoglossoides in the Davis Strait were studied through regularly collected samples during 1 year starting in spring 2003. Samples were collected from the southern slope of the Davis Strait Ridge between Canada and Greenland in the depth range 1000-1500 m. Female sexual maturation was described using different approaches: gonado-somatic index, visual macroscopic maturity stage index, histological microscopic maturity index and oocyte diameter measurements. A significant increase in the gonado-somatic index was seen from September onwards until February with a maximum estimated value of 18%. The proportion of mature fish increased from December until March. At the same time, the proportion of females with a low gonado-somatic index also increased from February, indicating that spawning had occurred and females were recovering. Oocyte diameter distribution revealed a leading cohort development during autumn through to December to February. A coupling between sexual maturity and fish condition was seen for females in maturing condition indicating a steady build up of stored energy in the liver from June to November.

Sunscreen application and its importance for the sun protection factor.

To achieve a good sun protection, a layer thickness of 2 mg/sq cm is often recommended. Fifty individuals were asked to apply five different sunscreens ad libitum. Ten percent dihydroxyacetone was added to the sunscreens in order to make them fluoresce when irradiated with Wood's light. The layer thickness was calculated by dividing the amount applied by the area. The thicknesses of the sunscreen layers varied little between different parts of the body and different brands; in general it was close to 1 mg/sq cm. The corresponding protection factor was measured for two sunscreens on 20 persons. The results indicate that the sun protection factor under ad libitum conditions is only 50% of what would be achieved using a layer thickness of 2 mg/sq cm.

Stability of PABA after UV irradiation in vivo and in vitro.

Sunscreens are widely used for the prevention of acute and chronic sun damage. One of the most widely used sunscreens is para-aminobenzoic acid (PABA). It has been reported that PABA decomposes on exposure to air and light as well as exposure to high doses of UVB. In the present study we found that PABA was stable during long-term storage. PABA seems to be stable after irradiation of physiological doses of UVA and UVB in vitro. However, the in vivo studies demonstrate that significantly less PABA could be extracted from UVA-irradiated sites compared to controls.

The facial expression of anger in seven-month-old infants.

This study concerned whether anger can be observed reliably in facial expressions as early as 7 months of age in a sample of 30 infants. It also assessed the influence of several variables on anger responses: infant's familiarity with the frustrator (mother vs. stranger), repetition of trials, and sex of the child. Correlations were obtained between the expression of anger and cognitive developmental level, maternal perceptions of irascibility (temperament), time since eating or sleeping, and facial flushing. Dependent variables included facial expression components as well as ratings of facial flushing. We found that the capacity to express anger is well developed by 7 months of age: facial patterning was detected reliably in the absence of contextual information, and repeated frustrations increased the amount of anger shown. No significant relationships were found, however, between facial expression of anger and temperament, drive states, or cognitive developmental scores.