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Results are presented from a new web application called OceanDIVA — Ocean Data Intercomparison and Visualization Application. This tool reads hydrographic profiles and ocean model output and presents the data on either depth levels or isotherms for viewing in Google Earth, or as probability density functions (PDFs) of regional model-data misfits. As part of the CLIVAR Global Synthesis and Observations Panel, an intercomparison of water mass properties of various ocean syntheses has been undertaken using OceanDIVA. Analysis of model-data misfits reveals significant differences between the water mass properties of the syntheses, such as the ability to capture mode water properties.

The present study was designed to determine the effect of the spatial gradient from the cervix to the uterine fundus on the control of local prostaglandin H synthase (PGHS) 2 mRNA expression. We performed total cesarean hysterectomies during the last trimester in 12 pregnant baboons, 7 not in labor and 5 in labor, and examined PGHS2 mRNA expression throughout the uterus. PGHS2 mRNA abundance was quantified by in situ hybridization and northern blot analysis in the uterine fundus, lower uterine segment and the different segments of the cervix. Quantitative northern blot and in situ analysis demonstrated a gradient of PGHS2 mRNA expression, with the highest levels at the level of the lower portion of the cervix and decreased expression through the mid- and upper portion of the cervix and lower uterine segment; the lowest levels of expression were seen in the uterine fundus. Moreover, cellular localization of PGHS2 mRNA and protein demonstrated high levels of expression in the cervical glandular epithelial cells with only occasional staining of smooth muscle cells in pregnant baboons. Decreased PGHS2 mRNA concentration gradient from the cervical external os to the fundus suggests that prostaglandin (PG) production in the uterus and cervix strongly depends on anatomical relations. This increased local PG production activity may be critical to pregnancy-associated lower uterine segment elongation, cervical softening and effacement in primate labor. These data provide a compelling biological basis for the use of PGHS2 inhibitors in the prophylaxis of preterm birth and cervical incompetence.

The aim of this study was to determine whether expression of prostanoid receptor genes varied with gestational age or labour in the decidua and chorion of baboons. Tissues were obtained at the time of Caesarean hysterectomy in 15 baboons, 10 prior to the onset of labour in the last third of pregnancy and 5 in spontaneous labour at term. Expression of prostanoid receptor genes was determined using Northern blot analysis and the level of expression was related to each of three housekeeping genes. Expression of the genes encoding the EP(1) and FP receptor in decidua and the EP(4) receptor in chorion was lower with advancing gestational age. Expression of the EP(2) receptor gene was lower in labour in decidua, whereas expression of the IP receptor gene was higher in labour in both decidua (twofold) and chorion (fourfold). It is concluded that there is a complex pattern of change in expression of prostanoid receptor genes in chorion and decidua with advancing gestational age and in association with labour. It seems likely that direct effects of prostaglandins on the choriodecidua may have an important role in parturition in the primate.

The aim of this study was to determine the effect of varying stretch of the ductus arteriosus on its contractile response to indomethacin and noradrenaline, and its relaxant response to prostaglandin (PG) E2. Isolated rings of ductus arteriosus obtained from fetal New Zealand White rabbits at 28 days gestation were mounted in vitro for measurement of isometric tension by a transducer connected to a vernier control. The responses of the ductus to drugs at varying degrees of passive stretch were corrected to a standard contraction in response to 65 mM potassium at a standard level of stretch. Increasing stretch across the range 1.0‐5.9 mN increased the contractile response to indomethacin and noradrenaline (the latter in the presence of 1 microM indomethacin and 1 or 10 nM PGE2) in a virtually identical manner. The sensitivity of the vessel to noradrenaline in the presence and absence of indomethacin and its sensitivity to the relaxant effect of PGE2 in the presence of indomethacin were unaffected by increasing stretch. The extent of contractile tone present which was not inhibited by endogenous PGE2 increased with increasing stretch. It was concluded that: (1) the contractile response to indomethacin can be profoundly altered by the degree of spontaneous tone in the vessel; (2) the magnitude of the contraction induced by indomethacin is not a good index of the degree of inhibition exerted by locally produced PGs in the vessel; and (3) locally produced PGs are likely to have a physiological role in maintaining patency of the ductus arteriosus in utero.

The Black-naped Tern breeds on cays and continental islands along the Great Bamer Reef, Australia. Studies of breeding and feeding were conducted at Eagle Island in the tropical north. Nesting was recorded from September to January. Egg laying was protracted over considerable periods in two of the three seasons of study. In all three seasons the first clutches for the breeding season, and for each subsequent wave of laying, were laid within a four-day period of the new moon and the number of eggs laid per day generally peaked within a few days of the full moon. Adults fed their chicks principally on the silver schooling fish belonging to the families Engraulidae, Atherinidae and Hemiramphidae. Feeding by adults occurred mostly in association with the reef surrounding Eagle Island. Adult terns hunted most actively during the early morning and late afternoon. Chick feeding rates were affected by (1) time: rates were highest in the late afternoon and lowest in the early afternoon; and (2) tides: rates were highest on flooding tides and lowest on ebbing tides. During the summer at Eagle Island, flooding tides occurred in the early morning and late afternoon at the time of new and full moons. Food seemed particularly abundant for chicks at this time. This may also explain why egg laying was linked to moon phases, because the male must courtship-feed the female all of her fish requirements just before egg laying.

The two heterocyclic compounds produced on irradiation of 3β-acetoxy-6- nitrocholest-5-ene (1) have been shown by chemical degradation to be 3β-acetoxycholest-4-eno[6,5,4-cd]isoxazole (3) and 3β-acetoxy-A- norcholestano[6,5-c]-2?-isoxazoin-5?-one (4), while those formed from 6-nitrocholest-5-ene (2) are the analogous compounds, cholest-4- eno[6,5,4-cd]isoxazole (5) and A-norcholestano[6,5-c]-2?-isoxazolin-5?- one (6).

The photochemistry of 3β-acetoxy-6-nitrocholest-5-ene (1) and 6- nitrocholest-5-ene (11) has been investigated in a number of solvents. It is suggested that for both compounds the major primary photo-product is the corresponding aci-nitro tautomer, which then undergoes further reactions depending mainly on the conditions employed. The aci-nitro compounds are believed to be formed by a 1,5-hydrogen shift from C4 to oxygen, and their intermediacy is supported by the formation of a mixture of 6α-deutero-6β-nitrocholest-4-ene and 6β-deutero-6α- nitrocholest-4-ene on irradiation of 6-nitrocholest-5-ene in Me3COD. Several other reactions of 3β-acetoxy-6-nitrocholest-5-ene and 6- nitrocholest-5-ene are described.

The photochemistry of cyclohexylidenenitromethane (6), 3-ethyl-2-nitropent-2-ene (7), (Z)-α-methyl-α- nitrostilbene (12), (E)-3-methyl- 1-nitro-1-phenylbut-1-ene (15) and 4,4-dimethyl-3-nitro-5α-cholest-2- ene (27) has been examined to determine the structural features required for deconjugation to the β, γ-unsaturated isomer. The mechanism of the light-induced formation of the corresponding α, β- unsaturated ketone , which may accompany deconjugation , has also been examined. Support for a scheme involving γ-hydrogen abstraction to give an unsaturated nitronic acid, followed by N- hydroxyoxaziridine formation and collapse to the ketone, is provided in the photochemistry of the stable nitronic acids, 4-t-butyl-aci-nitrocyclohexane (17) and 9-aci-nitrofluorene (18). Syntheses of the nitro olefins (6), (7), (12), (15) and (27), and the nitronic acid (17) are also reported.

In a mark-recapture study of small mammals, 92 female and 59 male AntechinusfIavipes were caught on Kinaba I. during 13 803 trap-nights and 8887 trap-days. A.flavipes mated almost synchronously in late August-early September each year. Young born in early October were carried in the pouch for approximately 36 days, cared for in the nest for a further 2-3 months and weaned through January. All males died within approximately 1 month of mating. Other causes of mortality included winter mortality, post-reproductive mortality amongst breeding females, and juvenile mortality after weaning; these types of population mortality were not severe. In one breeding season (1977-78), a proportion of females failed to give birth; with pouch mortality, significantly fewer young were weaned per female from this season than from others (1976-77, 1978-79). This was compensated for by greater post-weaning survival of young, so that demographic fluctuations and size of the trapped population did not differ appreciably between years. Young A.flavipes remained near to their place of birth for approximately 5 months after weaning. After this males dispersed further than did females. The timing of breeding for A.flavipes at Kinaba I. is discussed in relation to that of other Antechinus populations in eastern Australia. Timing of breeding is believed to be principally related to climatic factors.

This study examined the differences in the chemical composition of the lipid extracted from the fleeces of intact and gonadectomized Australian cashmere goats (Capra hircus laniger). Lipid was extracted with either petroleum ether or chloroform/methanol, and analysed by gas chromatography and gas chromatography/mass spectrometry. A large number of buck specific fatty acids (29), which could be potential pheromones, were identified or tentatively identified. The fatty acid composition of buck fleece lipid is more complex than previously reported.

Breeding of Roseate Terns Sterna dougallii on the northern Great Barrier Reef (11°-15°S) was monitored between 1976 and 1994, and they were recorded breeding on the inshore rocky islands in most years, usually starting April-May. Between 50-5000 pairs were recorded breeding each year and indicate that the northern Great Barrier Reef is an important breeding area for Roseate Terns during peak years when large colonies of 1000-5000 pairs formed on low sand cays in the far northern Great Barrier Reef (11°s). On at least three occasions, breeding success was poor in these large colonies, with high mortality of the almost-fledged chicks. Growth in weight and wing length of Roseate Tern chicks was measured at Eagle Island (14°42′S) between 1983 and 1986 in order to assess the influence of food on growth rates and survival. Chicks took up to 35 days to fledge, significantly longer than the ecologically similar, more numerous Black-naped Tern Sterna sumatrana at the same site at the same time and also almost 10 days longer than Roseate Tern chicks from temperate North American colonies. These data suggest that conditions in northern Australia are rarely favourable for the rapid growth and breeding success of Roseate Terns. Pelagic fish populations around inshore islands in tropical Australia may only be able to support limited numbers of Roseate Terns during the breeding season. This makes northeastern Australian populations of this globally threatened species extremely vulnerable to changes in the availability of their prey during the breeding season.

Silver gulls can threaten the welfare of humans and other wildlife. Current superabundant gull numbers should be managed to reduce this risk. Denying gulls access to food at artificial sites, combined with direct population control, may reduce silver gull numbers in the long term. Control measures implemented at gull colonies overseas were trialled. Human disturbance in the colony associated with routine visits to study plots led to reduced nesting density. Egg-pricking reduced nesting success; it did not induce adults to incubate for extended periods even though gulls were recorded sitting on nonviable (although not pricked) eggs for up to 76 days. Removal of eggs from nests within experimental plots did not affect overall nesting success for these plots. Habitat modification, by mowing of long grass at the colony site prior to the commencement of breeding, decreased both the density of nests in mowed areas and nesting success. Selective culling of breeding adults from experimental plots was effective in reducing population size immediately and suppressed nesting by other individuals that attempted to breed later in the breeding season. The combination of habitat modification, culling and human disturbance reduced breeding success at colonies.

Silver gulls have increased in abundance in Sydney-Wollongong this century. Both the number of colonies and their sizes have grown. The largest colony of 43 000-50000 pairs is on Big I., off Wollongong. Breeding was compared at this colony with that at a satellite colony on artificial structures in Rozelle Bay, Sydney Harbour. Breeding occurred from July to February at Big I., a lengthening of the season since the 1960s. At Rozelle Bay, breeding occurred almost all year round. Egg and clutch size varied within and between years at Big I. First-eggs of clutches, laid during the first breeding peak, were significantly larger than those laid later in each breeding season. The size of third-eggs in clutches differed between years. It is proposed that these disparities were a result of differences in food availability between years. Clutch sizes were significantly larger during the first breeding peak than later clutches of each season. Clutch size was larger at Rozelle Bay. Variation in clutch size was linked to quality of individuals and food availability. Breeding success at colonies was low, indicating that carrying capacities have been reached.

Measurements of bill size differed between gulls from three widely separated Australian regions, suggesting that there are a number of different subpopulations. When assigning an individual to a sex, a geographical locality factor should be incorporated into the discriminant model. Bill colour may be a useful tool for ageing gulls and detailed colour categories have been identified which could be used to define relative ages. Free-flying gulls are here ascribed to one of seven categories. Colour categories may not be universal; therefore, the population should be considered region by region.

Wing tags were used in preference to colour/metal band combinations to increase sighting frequency of silver gulls. Wing tags did not affect return rate of breeding adults to the colony compared with banded gulls. Approximately one-third of gulls lost their nests following wing-tagging. There were no instances of double-brooding with fledging success from both attempts. A total of 42% of adults that returned and bred, nested more than once in a season. Up to 4 clutches were produced by pairs within a season. Successful raising of young typically occurred from the first brood of the season. Successful breeders usually nested only once in any one season. In all, 19% of pairs successfully fledged young, but the percentage of young fledged from the number of eggs laid was much lower (5.3%). Nest sites were rarely repeatedly used by the same nesting pair. Individuals moved considerable distances between successive nesting sites within and between seasons. Fidelity to colony was 68% and to mate 22%; these estimates are lower than those from other colonies.

Treatment of 6β-nitrocholest-4-ene with a catalytic amount of sodium methoxide in methanol gave an equilibrium mixture which contained the starting material and the 6α-epimer in a 1 : 1 ratio. The unusual stability of the 6β-epimer is explained by electronic factors.