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Three sampling methods for estimating abundance and size of blue cod Parapercis colias were compared inside and outside Kapiti Marine Reserve, New Zealand (40° 49′ 31·77′′ S; 174° 55′ 02·87′′ E). Two baited methods, baited underwater video (BUV) and experimental angling (EA), were more efficient and had lower levels of estimate variation than diver-based underwater visual census (UVC). The BUV and EA recorded more fish and of greater size ranges than UVC, and also had fewer zero count replicates. The BUV and EA methodologies revealed highly significant differences in abundance and size of fish between sites (reserve v. non-reserve), whereas UVC revealed no such differences. These results indicate that BUV is likely to be the most accurate, cost-effective and easy to use methodology for the surveying of carnivorous temperate reef fishes for future monitoring. It is noted, however, that new data acquired using the BUV methodology may need to be compared over a calibration period to data acquired using the UVC methodology to ensure that historical data sets derived from UVC still have validity and application for future monitoring activity. [ABSTRACT FROM AUTHOR]

Low socio-economic status (SES) is associated with a shortened life expectancy, but its effect on aging is unknown. The rate of white-blood-cell (WBC) telomere attrition may be a biological indicator of human aging. We tested the hypothesis that SES is associated with telomere attrition independent of known risk factors influencing the aging process . We studied 1552 female twins. A venous blood sample was taken from each twin and isolated WBCs used for extraction of DNA. Terminal restriction fragment length (TRFL) was measured. Questionnaire data were collected on occupation, education, income, smoking, exercise, height and weight. Standard multiple linear regression and multivariate analyses of variance tested for associations between SES and TRFL, adjusting for covariates. A discordant twin analysis was conducted on a subset to verify findings. WBC telomere length was highly variable but significantly shorter in lower SES groups. The mean difference in TRFL between nonmanual and manual SES groups was 163.2 base pairs (bp) of which 22.9 bp (∼14%) was accounted for by body mass index, smoking and exercise. Comparison of TRFL in the 17 most discordant SES twin pairs confirmed this difference. Low SES, in addition to the harmful effects of smoking, obesity and lack of exercise, appears to have an impact on telomere length. [ABSTRACT FROM AUTHOR]

Insulin resistance and oxidative stress are associated with accelerated telomere attrition in leukocytes. Both are also implicated in the biology of aging and in aging-related disorders, including hypertension. We explored the relations of leukocyte telomere length, expressed by terminal restriction fragment (TRF) length, with insulin resistance, oxidative stress and hypertension. We measured leukocyte TRF length in 327 Caucasian men with a mean age of 62.2 years (range 40–89 years) from the Offspring cohort of the Framingham Heart Study. TRF length was inversely correlated with age ( r = –0.41, P < 0.0001) and age-adjusted TRF length was inversely correlated with the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) ( r =–0.16, P = 0.007) and urinary 8-epi-PGF2α ( r = –0.16, P = 0.005) – an index of systemic oxidative stress. Compared with their normotensive peers, hypertensive subjects exhibited shorter age-adjusted TRF length (hypertensives = 5.93 ± 0.042 kb, normotensives = 6.07 ± 0.040 kb, P = 0.025). Collectively, these observations suggest that hypertension, increased insulin resistance and oxidative stress are associated with shorter leukocyte telomere length and that shorter leukocyte telomere length in hypertensives is largely due to insulin resistance. [ABSTRACT FROM AUTHOR]

Abstract Single-strand conformation polymorphism (SSCP) analysis of the NADH IV region of the mitochondrial DNA (mtDNA) molecule in greenshell mussels (Perna canaliculus ) indicated strong population genetic structuring in this endemic New Zealand species. A northern and a southern group were differentiated by frequency shifts in common haplotypes and by the occurrence of a unique southern haplotype at ≈ 20% frequency. This split occurred south of Cook Strait (the body of water between the North and the South Island) at ≈ 42° S latitude. Northern populations were less genetically diverse than southern populations and mussels from the west coast of the South Island were most distinct from northern mussels. We hypothesize that the unique haplotype VIII originated in the lower South Island, and that its spread northwards was obstructed by the opening of Cook Strait ≈ 15 000–16 000 years ago and the subsequent establishment of present-day surface water circulation patterns in Greater Cook Strait. We suggest that present-day strong tidal flows and turbulent mixing of water masses in Cook Strait, and intense up-welling on the east and west coasts in this region, represent a barrier to gene flow between mussels located in the North Island and northern South Island vs. mussels in most of the South Island and Stewart Island. [ABSTRACT FROM AUTHOR]

Mytilus galloprovincialis is one of three smooth shelled blue mussel species belonging to the Mytilus edulis species complex. Naturally occurring and introduced populations of M. galloprovincialis are widely distributed throughout many regions of the globe. Mytilus galloprovincialis includes morphologically indistinguishable Northern and Southern hemisphere mtDNA lineages that have been separated for ∼1 my. To distinguish recently introduced Northern M. galloprovincialis from resident Southern M. galloprovincialis in New Zealand, we developed a 16s rRNA RFLP assay. We compared RFLP assignments of 178 mussels with those generated from a 16s rRNA sequence-estimated phylogeny. All mussels were correctly assigned by the RFLP to their sequence-based phylogenetic placement. This assay allows the rapid identification of Northern and Southern hemisphere M. galloprovincialis and will provide an important tool for monitoring human mediated introductions of otherwise cryptic lineages. [ABSTRACT FROM AUTHOR]

Describes the mitochondrial DNA obtained from gonad tissue of the greenshell mussel, Perna canaliculus. Reason for the mitochondrial origin of the DNA; Methods used in obtaining the clones; Polymorphisms.

An experiment was conducted to study the movement of surface-appliedtracers and fertilizer to groundwater on an agricultural field under dryland farming practices. Movement of surface-applied bromide, chloride, and fluoride tracers, and fertilizer nitrate (NO3) through a coarse-loamy glacial till soil and vadose zone to saturated glacial till at about 3 to 4 m, and to a confined aquifer at 6.8 m, were monitored for 5-yr. Crop treatments were a dryland rotation ofwheat (Triticam aestivam L.), soybean [Glycine mar (L.) Merr.l, and sunflower (Hetianrhus annuus L.). Applied bromide, chloride, and NO3 could be detected in trace amounts at all levels, including the aquifer, within a few days after application and following large summer storms. Within the root zone, NO3 and chloride concentrations varied with root extraction and application placement. The largest stable concentration of solute occurred within the shallowvadose zone beneath the root zone. Below the root zone, tracer and NO3 concentrations decreased exponentially with depth. Following a large rainfall the shallow vadose layer served as a 'feeder zone' for solute movement to deeper layers. Elevated concentrations following recharge events were spatially sporadic, occurring at some locations and not at others. Spatially variable and temporary increasesin solute concentrations were caused by spatially variable recharge,governed by microtopographic controls. Water concentrated in microtopographical 'low' areas and moved in concentrated plugs to the water table carrying solute. NO3-N did not increase in the saturated till or the aquifer over the 5-yr period. [ABSTRACT FROM AUTHOR]