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Observational evidence suggests that in populations consuming low levels of n-3 highly unsaturated fatty acids, women have higher blood levels of docosahexaenoic acid (DHA; 22:3n-6) as compared with men. Increased conversion of alpha-linolenic acid (ALA; 18:3n-3) to DHA by females has been confirmed in fatty acid stable isotope studies. This difference in conversion appears to be associated with estrogen and some evidence indicates that the expression of enzymes involved in synthesis of DHA from ALA, including desaturases and elongases, is elevated in females. An estrogen-associated effect may be mediated by peroxisome proliferator activated receptor-α (PPARα), as activation of this nuclear receptor increases the expression of these enzymes. However, because estrogens are weak ligands for PPARα, estrogen-mediated increases in PPARα activity likely occur through an indirect mechanism involving membrane-bound estrogen receptors and estrogen-sensitive G-proteins. The protein kinases activated by these receptors phosphorylate and increase the activity of PPARα, as well as phospholipase A₂ and cyclooxygenase 2 that increase the intracellular concentration of PPARα ligands. This review will outline current knowledge regarding elevated DHA production in females, as well as highlight interactions between estrogen signaling and PPARα activity that may mediate this effect.

Grass shrimp are abundant residents of shallow-water habitats in US Atlantic and Gulf coast estuaries. Mark-recapture events determined the extent and direction of their movements in meso-tidal salt marsh creeks at North Inlet, South Carolina. Microwire-tagged Palaemonetes vulgaris demonstrated high fidelity for a dock in a subtidal channel. In the 48 days following release, 11 % of the 422 tagged shrimp were recaptured and 99 % of all recaptures were made there an average of 14 days post-release. Palaemonetes pugio, which favored the use of shallow intertidal areas, exhibited moderate fidelity for pools within creek beds with 53 % of the recaptured shrimp collected at the release site. Higher fidelity was observed for confluences of intertidal creeks and the subtidal channels. Of the 5565 shrimp released with coded microwire tags, 7.5 % were recaptured and 98 % of those recaptures were at release sites up to 53 days later. During another event, P. pugio released 235 m from their origin demonstrated relatively low fidelity for the new site and a lack of homing behavior. Of the 544 tagged shrimp, 3 % were recaptured; only 40 % of those recaptured were from the release site. Site fidelity is a mechanism by which previously discovered large and consistent differences in grass shrimp use of neighboring intertidal creek basins can be sustained over weeks, seasons, and years. Spatial variations and the tendency of these keystone organisms to resist relocation by tidal currents and occupy certain areas for extended periods should be considered in decisions about proposed alterations to creeks and shorelines.

The Maltese Megalithic Temples, constructed between the mid-fourth and mid-third millennia BC, are unique and are amongst the oldest stone buildings of such complexity in the world. They are of great local and international significance, embodying symbolic, educational and recreational values. These Temples are currently suffering from a series of severe problems associated with the deterioration of materials as well as structural problems, seen in a number of serious collapses in recent years. In 2000, it was decided that these vulnerable prehistoric structures needed to be protected from the direct impact of environmental factors by means of a temporary, open-sided shelter, conceived as a large parasol designed to be as light as possible, in visual as well as in physical terms. The erection of two of these shelters took place during 2008–2009. The performance of the shelters is currently being assessed by environmental monitoring which already indicates an improvement in conditions beneath the shelters when compared to conditions on site before sheltering.

Although wildlife biologists need reliable estimates of white-tailed deer (Odocileus virginianus) density to facilitate management, few studies have examined distance sampling as a density estimation technique for this species. We compared direct (i.e., spotlighting from road transects) and indirect (i.e., counting pellets on randomly placed transects) distance-sampling techniques for estimating deer densities in east-central Illinois, southern Illinois, and northern Michigan (USA) during 2007–2008. Density estimates (95% CI) from indirect distance sampling for northern Michigan, east-central Illinois, and southern Illinois were 6.1–12.7 deer/km2, 11.2–15.8 deer/km2, and 15.4 deer/km2, respectively. Density estimates from direct distance sampling for northern Michigan, east-central Illinois, and southern Illinois were 18.3– 25.2 deer/km2, 14.4–18.1 deer/km2, and 19.0 deer/km2, respectively. Although density estimates did not differ between techniques in east-central Illinois and southern Illinois, density estimates derived by direct sampling were slightly higher than those derived by indirect sampling. Estimates of density from direct distance sampling were higher than indirect distance sampling in northern Michigan. The difference in estimates among study areas may be due to landscape-specific differences in the behavioral response of deer to roads and the representativeness of road transects. In landscapes containing more agriculture, roads tend to be systematically distributed and forest edges are independent of road placement, which may explain why both distance-sampling methods provided similar results in Illinois. However, in more forested landscapes such as Michigan, roads tend to follow streams and may provide forest edges that are relatively scarce on the landscape. Deer in forested landscapes may be attracted to roadsides, resulting in higher density estimates not indicative of surrounding forested areas. Therefore, use of road transects for direct distance sampling may be more applicable in non-forested landscapes.

Results from six continuous and semicontinuous black carbon (BC) and elemental carbon (EC) measurement methods are compared for ambient samples collected from December 2003 through November 2004 at the Fresno Supersite in California. Instruments included a multi-angle absorption photometer (MAAP; λ = 670 nm); a dual-wavelength (λ = 370 and 880 nm) aethalometer; seven-color (λ = 370, 470, 520, 590, 660, 880, and 950 nm) aethalometers; the Sunset Laboratory carbon aerosol analysis field instrument; a photoacoustic light absorption analyzer (λ = 1047 nm); and the R&P 5400 ambient carbon particulate monitor. All of these acquired BC or EC measurements over periods of 1 min to 1 hr. Twenty-four-hour integrated filter samples were also acquired and analyzed by the Interagency Monitoring of Protected Visual Environments (IMPROVE) thermal/optical reflectance carbon analysis protocol. Site-specific mass absorption efficiencies estimated by comparing light absorption with IMPROVE EC concentrations were 5.5 m 2 /g for the MAAP, 10 m 2 /g for the aethalometer at a wavelength of 880 nm, and 2.3 m 2 /g for the photoacoustic analyzer; these differed from the default efficiencies of 6.5, 16.6, and 5 m 2 /g, respectively. Scaling absorption by inverse wavelength did not provide equivalent light absorption coefficients among the instruments for the Fresno aerosol measurements. Ratios of light absorption at 370 nm to those at 880 nm from the aethalometer were nearly twice as high in winter as in summer. This is consistent with wintertime contributions from vehicle exhaust and from residential wood combustion, which is believed to absorb more shorter-wavelength light. To reconcile BC and EC measurements obtained by different methods, a better understanding is needed of the wavelength dependence of light-absorption and mass-absorption efficiencies and how they vary with different aerosol composition.

Chromatin remodelers alter DNA–histone interactions in eukaryotic organisms and have been well characterized in yeast and Arabidopsis. While there are maize proteins with similar domains as known remodelers, the ability of the maize proteins to alter nucleosome position has not been reported. Mutant alleles of several maize proteins (RMR1, CHR101, CHR106, CHR127, and CHR156) with similar functional domains to known chromatin remodelers were identified. Altered gene expression of Chr101, Chr106, Chr127, and Chr156 was demonstrated in plants homozygous for the mutant alleles. These mutant genotypes were subjected to nucleosome position analysis to determine whether misregulation of putative maize chromatin proteins would lead to altered DNA–histone interactions. Nucleosome position changes were observed in plants homozygous for chr101, chr106, chr127, and chr156 mutant alleles, suggesting that CHR101, CHR106, CHR127, and CHR156 may affect chromatin structure. The role of RNA polymerases in altering DNA–histone interactions was also tested. Changes in nucleosome position were demonstrated in homozygous mop2‐1 individuals. These changes were demonstrated at the b1 tandem repeats and at newly identified loci. Additionally, differential DNA–histone interactions and altered gene expression of putative chromatin remodelers were demonstrated between different maize haplotypes.

Between 1983 and 1986 the National Wildlife Health Center (NWHC) conducted a nationwide study of lead poisoning of waterfowl from federal and state refuges. This survey was done to assist in identifying zones with lead-poisoning problems. One thousand forty one moribund or dead waterfowl were collected and examined. The presence or absence of 13 gross lesions selected as indicators of lead poisoning and three lesions indicating body condition was recorded. Lead-poisoning diagnoses were based on the finding of at least 6-8 ppm (wet weight) lead in the liver and either lead shot in the gizzard content or at least one convincing gross lesion indicative of lead poisoning. Four hundred twenty-one of these waterfowl were diagnosed as lead poisoned. The NWHC survey provided a comprehensive basis for estimating the sensitivities, specificities, and likelihood ratios of the gross lesions of lead poisoning and the associated hepatic lead concentrations for several species of waterfowl. Some of the 13 defined gross lesions were more common than others; frequencies ranged from 3% to 80% in the 421 lead-poisoned waterfowl. The most reliable indicators of lead poisoning were impactions of the upper alimentary tract, submandibular edema, myocardial necrosis, and biliary discoloration of the liver. Each of the 13 lesions occurred more frequently in the lead-poisoned birds, but each of the lesions also occurred in waterfowl that died of other causes. The number of lead shot present in a bird's gizzard was only weakly correlated with its hepatic lead concentration; however, this weak correlation may have been adequate to account for differences in hepatic lead concentrations among species, once the weights of the species were taken into account. Although lead-poisoned ducks tended to have higher hepatic mean lead concentrations than did lead-poisoned geese or swans, the differences were probably a result of a greater dose of shot per body weight than to kinetic differences between species. Hepatic lead concentrations were independent of age and sex. Ninety-five percent of waterfowl diagnosed as lead poisoned had hepatic lead concentrations of at least 38 ppm dry weight (10 ppm wet weight). Fewer than 1% of the waterfowl that died of other causes had a concentration that high. This fifth percentile, of 38 ppm dry weight (10 ppm wet weight), is a defensible criterion for identifying lead-poisoned waterfowl when interpreting hepatic lead concentrations in the absence of pathological observations.

Ozone emissions were measured above a \"personal air purifier\" (PAP) designed to be worn on a lapel, shirt pocket, or neck strap. The device is being marketed as a negative ion generator that purifies the air. However, it also produces ozone within the person's immediate breathing zone. In order to assess worst-case potential human exposure to ozone at the mouth and nose, we measured ozone concentrations in separate tests at 1, 3, 5, and 6 in. above each of two PAPs in a closed office. One PAP was new, and one had been used slightly for 3 months. Temperature, relative humidity, atmospheric pressure, room ozone concentration, and outdoor ozone concentration also were measured concurrently during the tests. Average ozone levels measured directly above the individual PAPs ranged from 65-71 ppb at 6 in. above the device to 268-389 ppb at 1 in. above the device. Ozone emission rates from the PAPs were estimated to be 1.7-1.9 microg/minute. When house dust was sprinkled on the top grid of the PAPs, one showed an initial peak of 522 ppb ozone at 1 in., and then returned to the 200-400 ppb range. Room ozone levels increased by only 0-5 ppb during the tests. Even when two PAPs were left operating over a weekend, room ozone levels did not noticeably increase beyond background room ozone levels. These results indicate that this \"PAP,\" even without significant background ozone, can potentially elevate the user's exposures to ozone levels greater than the health-based air quality standards for outdoor air in California (0.09 ppm, 1-hour average) and the United States (0.08 ppm, 8-hour average).