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We present a multi-proxy, postglacial paleorecord from Chase Lake, a 1.63-km2 drainage lake in northern Maine. This record, along with published paleorecords from several smaller lakes and hollows allow us to synthesize a long-term natural history of the area. Northern Maine is unique in the northeastern USA as it was the last part to be deglaciated and has maintained a relatively cold climate and boreal flora. The diverse lake/catchment sites differed in dates of deglaciation (13,700 to 13,200 cal yr BP) and the duration of the ensuing tundra period (1700 to 2900 cal yr). A dry, cold climate slowed plant establishment. Chase Lake had low aquatic productivity until the end of the tundra period. The Chase record shows that afforestation began ∼10,600 cal yr BP, ∼1000 years after the end of the Younger Dryas, and 700–1400 years later than at the other sites, and was completed by 9200 cal yr BP. Initial open woodlands of Picea (spruce) (largely P. mariana [Black Spruce]), Abies balsamea (Balsam Fir), Larix laricina (American Larch), Pinus (pines), Betula papyrifera (Paper Birch), and Populus (poplars) gradually became closed forest. Climate substantially warmed at the outset of afforestation. Despite evidence of an increasingly wetter climate, as indicated by rising water levels at 2 seepage lakes, fire was common for the first 2000–3000 years of woodland and forest history, probably enabled by summer droughts. This fire period is not matched in intensity and duration later in the paleorecords. At Chase, afforestation was accompanied by an increase in insect remains including microlepidopteran defoliators, and these remained abundant for the rest of the record. Major increases of aquatic biota accompanied afforestation. Spruce greatly decreased by ∼7500 cal yr BP as northern hardwoods and Tsuga canadensis (Eastern Hemlock) increased, but hemlock abundance remained low compared to farther south in the Northeast. From 7500 to 1300 cal yr BP, temperate tree taxa were at maximum abundances. Spruce and fir were at postglacial minima 6250–4400 cal yr BP. A relatively dry period 5300–3300 cal yr BP nearly eliminated hemlock at the outset, when it was replaced largely by Fagus (beech). Hemlock's partial recovery late in that period was accompanied by increasing Thuja (cedar) and decreasing Quercus (oak), the beginning of climate cooling and resumption of wetter conditions. This climate trend intensified after 3300 cal yr BP, resulting in further increases of cedar, spruce (largely Picea rubens [Red Spruce] and Black Spruce) and fir, which reached greatest postglacial abundances in the most recent 1000–1500 years. Long-term natural histories of selected woody taxa provide insights on ecological factors accounting for changes in species abundances. For example, the flourishing of cedar in the late-Holocene could have been abetted by increasing winter severity that eliminated Odocoileus virginianus (White-tailed Deer), heavy browsers on cedar. The geochemical history of the Chase catchment demonstrates ongoing weathering and depletion of several metals, resulting in enrichment of soils with silica. Several changes in metal concentrations are linked to afforestation, including increased transport to the lake sediment of Ca, K, Al, Fe, Cu, and Zn in/on increased organic detritus. Accumulation rates of metals and organic materials in the Chase Lake sediment were probably heavily influenced by physical processes including catchment erosion, shifts in sediment sources, and in-lake focusing.

Predators and scavengers play a vital role in regulating insect pests, weeds, and vertebrate scat in perennial agroecosystems. Understanding how farm management practices and surrounding habitat influence these beneficial ecosystem services contributes to our understanding of these complex ecological systems and guides future management decisions. In a mensurative 2-yr study, we determined how different pest management strategies and surrounding forest composition influenced levels of sentinel insect pupae, weed seeds, and deer scat (feces) removal. Removal of these bioresources was measured within 12 commercial lowbush blueberry fields during 2011 and 2012; farms differed in surrounding landscape composition and farm management strategies. Both the removal of sentinel pupae and scat, was significantly higher within field interiors than at field edges and within adjacent forests. Additionally, farm management strategy interacted with field position to result in significantly higher scat removal in conventional field interiors than organic field interiors. Surrounding forest composition had variable effects on removal of materials. Our results indicate higher levels of activity within field centers as opposed to field edges; this is contrary to what has been observed in other perennial cropping agroecosystems.

These studies were conducted to determine the most effective methods for increasing shoot elongation during the initial proliferation stage of micropropagation in two dwarfing apple, Malus ×domestica (Borkh.), rootstock cultivars. Several experiments were conducted to compare explant collection date, exposure to chilling (5 ± 1 °C) temperatures, and varying concentrations of plant growth regulators in Murashige and Skoog (MS) media. Microshoot growth of ‘Geneva 41’ (‘G.41’) was very low and unaffected by chilling duration from 0 to 8 weeks or by gibberellic acid (GA3) concentration from 0 to 1.0 mg·L−1, but was improved by an additional subculture which increased shoot length from 1 to 15 mm. In ‘Geneva 30’ (‘G.30’), shoot elongation was most affected by date, chilling explants, and by optimizing cytokinin concentration and type. Explant collection date in April increased shoot growth compared with August or November. Microshoot growth of ‘G.30’ was increased by chilling nodal explants for 4 and 6 weeks when explants were collected in August and November, but not in April. Eight weeks chilling was detrimental for explants collected in April, and generally had little or no effect with August and November. The cytokinin 6-benzylaminopurine (BA) increased shoot number to a greater extent than thidiazuron (TDZ) or zeatin (ZT), and was also more effective for increasing shoot elongation with concentrations of 0 to 2.0 mg·L−1. In ‘G.30’, GA3 increased shoot growth at the optimum concentration of BA, but not with lower concentrations. ‘G.30’ microshoots were fewer and shorter with 24-epi-brassinolide (EBR) at concentrations of 0.1 and 1.0 mg·L−1. Chemical names: N-phenyl-N’-(1,2,3-thiadiazol-5-yl)urea (TDZ), 6-(4-hydroxy-3-methylbut-2-enylamino)purine (ZT).

It is well known in ecological studies that the choice of spatial scale can influence the possibility of detecting ecological patterns and the type of patterns observed. However, this has rarely been evaluated for fish stock–recruitment (SR) dynamics. Inappropriate scales may result in failure to identify possible SR relationships, especially for species with complicated life history and stock structure and locally generated recruitment. Using American lobster (Homarus americanus) in the Gulf of Maine (GOM) as an example, we tested the hypotheses that the SR relationship is detectable only at certain spatial scales and the functional SR relationships vary with spatial scales. We estimated the SR relationship separately for American lobster in the eastern and western GOM, which have strongly differing oceanographic conditions that may result in different suitable spatial scale and SR dynamics for lobster. We analyzed data of 11 different spatial scales using a Bayesian method. The model fit and performances in the posterior predictive assessment for the SR models were convexly related to the spatial scales. The functional SR relationships differed for different spatial scale. The SR parameter estimates are negatively or concavely related to the spatial scale. The best model was found at medium spatial scale for both the eastern and western GOM, and the scale differed between the eastern and western GOM, suggesting that optimal spatial scale might be process-related. We demonstrated that the choice of spatial scale directly affected the possibility of identifying the SR relationship, the estimation of SR parameters, the type of SR relationships, and the predictive abilities of the SR models.

During April – June 1987 and 1988, we remotely monitored 14 radio-marked female American Woodcock (Scolopax minor; hereafter woodcock) at 18 nest sites on Moosehorn National Wildlife Refuge in Maine, U.S.A., to determine patterns and constancy of nest incubation behavior. On average, females spent 93% of their time on the nest and 7% off the nest, leaving nests for an average of 104.2 minutes during a 24-hour period. Time off the nest each day did not vary by year, daily high temperature, or amount of daily precipitation. Our data suggest that renesting females spent more time off nest/day than females on first nests, and that second-year females made more diurnal recesses from the nest than aftersecond- year females. Most woodcock left the nest during crepuscular periods. Our results provide information about nest incubation constancy, and may be useful for informing woodcock research and habitat management.

The influence of red and blue light wavelengths was tested to improve the initial in vitro multiplication of apple (Malus × domestica) rootstock cultivars Budagovsky 9 (B.9), Geneva 30 (G.30), and Geneva 41 (G.41). Single-node segments were established in semisolid Murashige and Skoog media and then transferred to proliferation media and cultured 40 days under white, red, or blue light irradiance. In a second experiment, G.30 was cultured under red, blue, or white light with and without gibberellic acid (GA3). The three rootstocks responded similarly under white light in terms of shoot number, length of the longest shoot, and the number of elongated shoots. Red light increased the number of shoots, length of the longest shoot, and the number of elongated shoots of B.9 and G.30 when compared with white or blue light. Red light increased the number of elongated B.9 and G.30 shoots to five per explant compared with one per explant under white light. In contrast, shoot growth of G.41 showed no difference under the three light quality treatments, and the number of elongated shoots per explant was less than one. When compared with an absence of GA3, a concentration of GA3 at 0.5 mg·L−1 promoted in vitro shoot growth of G.30 under red and blue light.

Ursine hibernation uniquely combines prolonged skeletal unloading, anuria, pregnancy, lactation, protein recycling, and lipolysis. This study presents a radiographic and biochemical picture of bone metabolism in free-ranging, female American black bears (Ursus americanus) that were active (spring bears and autumn bears) or hibernating (hibernating bears). Hibernating bears included lactating and non-lactating individuals. We measured serum calcium, albumin, inorganic phosphate, creatinine, bone specific alkaline phosphatase (BSALP), CTX, parathyroid hormone, insulin-like growth factor-I (IGF-l), leptin, 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D] and sclerostin from 35 to 50 tranquilized hibernating bears and 14 to 35 tranquilized spring bears. We compared metacarpal cortical indices (MCI), measured by digital X-ray radiogrammetry, from 60 hunter-killed autumn bears and 79 tranquilized, hibernating bears. MCI was greater in autumn than winter in younger bears, but showed no seasonal difference in older bears. During hibernation eucalcemia was maintained, BSALP was suppressed, and CTX was in the range expected for anuria. During hibernation 1,25(OH)(2)D was produced despite anuria. 1,25(OH)(2)D and IGF-I were less in hibernating than spring bears. In a quarter of hibernating bears, sclerostin was elevated. Leptin was greater in hibernating than spring bears. In hibernating bears, leptin correlated positively with BSALP in non-lactating bears and with CTX in lactating bears. Taken together the biochemical and radiographic findings indicate that during hibernation, bone turnover was persistent, balanced, and suppressed; bone resorption was lower than expected for an unloaded skeleton; and there was no unloading-induced bone loss. The skeleton appears to perceive that it was loaded when it was actually unloaded during hibernation. However, at the level of sclerostin, the skeleton recognized that it was unloaded. During hibernation leptin appeared anabolic in non-lactating bears and catabolic in lactating bears. We hypothesize that ursine hibernation may represent a natural model in which suppression of the sympathetic nervous system prevents unloading-induced bone loss by influencing leptin's skeletal effects and preventing transmission of loading information.

Terminal restriction fragment length polymorphism (T-RFLP) can be used to assess how land use management changes the dominant members of bacterial communities. We compared T-RFLP profiles obtained via amplification with forward primers (27, 63F) each coupled with the fluorescently labeled reverse primer (1392R) and multiple restriction enzymes to determine the best combination for interrogating soil bacterial populations in an agricultural soil used for potato production. Both primer pairs provide nearly universal recognition of a 1,400-bp sequence of the bacterial domain in the V(1)-V(3) region of the 16S ribosomal RNA (rRNA) gene relative to known sequences. Labeling the reverse primer allowed for direct comparison of each forward primer and the terminal restriction fragments' relative migration units obtained with each primer pair and restriction enzyme. Redundancy analysis (RDA) and nested multivariate analysis of variance (MANOVA) were used to assess the effects of primer pair and choice of restriction enzyme on the measured relative migration units. Our research indicates that the 63F-1392R amplimer pair provides a more complete description with respect to the bacterial communities present in this potato (Solanum tuberosum L.)-barley (Hordeum vulgare L.) rotation over seeded to crimson clover (Trifolium praense L.). Domain-specific 16S rRNA gene primers are rigorously tested to determine their ability to amplify across a target region of the gene. Yet, variability within or between T-RFLP profiles can result from factors independent of the primer pair. Therefore, researchers should use RDA and MANOVA analyses to evaluate the effects that additional laboratory and environmental variables have on bacterial diversity.

In order to maintain biodiversity in forests, it has been recommended that harvests be designed after patterns of natural disturbance. Using a long-term study that includes harvest treatments designed to emulate tree-fall gap disturbances in Maine’s Acadian forest, we examined how the species richness, abundance, diversity, and assemblage similarity of click beetles inhabiting coarse woody material (CWM) were affected by gap harvesting and CWM characteristics (diameter, degree of decay, and type of wood). There were few differences in beetle assemblages between 0.07 and 0.12 ha harvest gap treatments. Four of the most common species had higher abundances under a closed forest canopy than within harvest gaps. Species richness and total abundance were higher in CWM that had larger diameters and were more decayed. Species assemblages also differed with the degree of wood decomposition. Diversity was higher in CWM from softwood trees than hardwood trees. Results from this study suggest that small ( 35 cm).

An emerging disease of amphibians caused by the chytrid fungus Batrachochytrium dendrobatidis has been associated with morbidity, mortality, and extinction of species. Typically, researchers have detected B. dendrobatidis only when examining amphibians for causes of mortalities; few data exist on infection rates where mortalities are lacking. During May–September 2000–2002 we obtained amphibian specimens killed by vehicles and others collected at remote off-road sites throughout Maine, USA, and from federal lands in 5 states in the Northeast. We detected infected specimens, mostly green frogs (Rana clamitans), at 5 of 7 national wildlife refuges, a federal waterfowl production area, and Acadia National Park. Seven of 9 species, including all Ranidae species, were infected throughout Maine; rates ranged from 14.6% in American toads (Bufo americanus) to 25.7% in northern leopard frogs (Rana pipiens). We did not detect any infections in 50 eastern gray tree frogs (Hyla versicolor) or 21 spring peepe...

We investigated two pest management strategies for Pyrrhalta viburni (Paykull), a non-native leaf beetle that has invaded New England and is defoliating susceptible wild and cultivated species of Viburnum. SurroundWP (kaolin wettable powder) was tested as a barrier spray during container production of V. dentatum, to determine if it would affect P. viburni leaf damage, oviposition and plant growth. The effect of added N (nitrogen) was also tested. SurroundWP significantly lowered leaf damage and numbers of egg masses in amended plants, without a negative effect on plant growth. Nitrogen use significantly increased leaf damage by adults, numbers of egg masses, and plant growth. These results suggest that commercial growers of susceptible Viburnum species in areas where P. viburni is found could benefit from the use of SurroundWP, and that N amendment should be kept to a minimum.

This pilot study sought to determine the rate and degree to which gram-negative Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa and gram-positive Staphylococcus aureus occurred on the inside of utility gloves used at University of Maine at Augusta, Dental Health Programs' dental hygiene clinic.Five steam autoclave utility gloves were randomly selected to serve as control and a convenience sample of 10 used utility gloves were selected from the sterilization area. A sample was collected from a predetermined surface area from the inside of each steam autoclave utility glove and used utility glove. Each sample was used to inoculate a Petri plate containing 2 types of culture media. Samples were incubated at 37° C for 30 to 36 hours in aerobic conditions. Colony forming units (CFU) were counted.Confidence intervals (CI) estimated the rate of contamination with gram-negative K. pneumoniae, E. coli and P. aeruginosa on the inside of steam autoclave utility gloves to be n=33 95% CL [0.000, 0.049], used utility gloves to be n=70, 95% CL [0.000, 0.0303]. Data estimated the rate of contamination with gram-positive S. aureus on the inside of steam autoclave utility gloves to be n=35, 95% CL [0.233, 0.530], used utility gloves to be n=70, 95% CL [0.2730, 0.4975]. Culture media expressed a wide range of CFU from 0 to over 200.The risk of utility glove contamination with gram-negative bacteria is likely low. The expressed growth of S. aureus from steam autoclave utility gloves controls raises questions about the effectiveness and safety of generally accepted sterilization standards for the governmentally mandated use of utility gloves.

Numbers of American woodcock (Scolopax minor) males counted on the annual singing ground survey (SGS) have declined over the last 35 years at an average rate of 2.3% per year in the Eastern Region and 1.8% per year in the Central Region. Although hunting was not thought to be a cause of these declines, mortality caused by hunters can be controlled. Furthermore, there has been no research on effects of hunting mortality on woodcock populations at local and regional levels on the breeding grounds. We used radiotelemetry to determine survival rates and causes of mortality for 913 woodcock captured during fall 1997–2000 on 7 areas in Maine, New Hampshire, Pennsylvania, and Vermont, USA. Three of 7 sites were closed to hunting. For all sites and all years combined, 176 woodcock died, and 130 were censored, of which 39 were censored mortalities. Predation was the major (n = 134, 76%) cause of mortality. Mammals accounted for 56% of the predation, raptors accounted for 25%, and 19% was attributed to unk...

The behavior of two strains of Listeria monocytogenes (147 and ATCC 19111) was evaluated at different stages of salmon processing. At lower temperatures of 2, 7, and 11 degrees C, L. monocytogenes survived on dry wood surfaces for at least 3 days without added nutrients but was unrecoverable after 2 days at 22 degrees C. Moisture or minimal nutrients on the wood surface increased viability of L. monocytogenes at all incubation temperatures. When large amounts of nutrients were provided, the recoveries of L. monocytogenes at low temperatures (< or = 11 degrees C) were essentially unchanged over the 3-day holding period, and rapid growth was observed at room temperature. In the presence of natural microflora, L. monocytogenes died off rapidly in seawater within 36 h at room temperature. When held at < or = 11 degrees C, L. monocytogenes lost viability throughout storage but was still detectable after more than 6 days of incubation. In the absence of natural microflora, both strains of L. monocytogenes were static during the holding period at all temperatures. At 2, 7, and 11 degrees C, L. monocytogenes in nonsterile salmon blood-water remained viable even after 6 days of incubation, whereas in sterile blood-water, growth of L. monocytogenes was observed at 7 and 11 degrees C. In the absence of natural microflora, L. monocytogenes grew better than it did in the presence of natural microflora. L. monocytogenes 147 was more competitive with background organisms than was L. monocytogenes ATCC 19111. No L. monocytogenes could be detected in the digestive tract of salmon 3 days after its introduction. The survival pattern of L. monocytogenes in fish digestive tracts was similar, regardless of whether the fish were feeding or not. A noticeable decline in the pathogen was observed as early as 3 h after introduction.

Differential participation after recruitment remains a black box in the social-movement and voluntary-association literatures. This paper identifies several dimensions of membership participation in a professional social-movement organization (SMO) with a national membership and analyzes the determinants of differential involvement in these forms. In general, members’ ideological beliefs, social and organizational ties, perceptions about their SMO, and communication with SMO officials all predict participation across the various forms. Our findings extend previous work on differential participation in three ways. First, we statistically isolate cultural dimensions of postrecruitment participation and, in so doing, complement recent ethnographic research. Second, our findings suggest that the distinct dimensions of external and internal participation found by Knoke (1988) in a national sample of voluntary associations may not generalize to national SMOs studied individually. Third, our results indicate that models combining ideological and microstructural factors should explain the multiple forms of participation in SMOs lacking these distinct dimensions.

Using a soil bioassay technique, seedling growth and incidence of disease of wild mustard (Brassica kaber) and sweet corn (Zea mays) were assessed in soil from field plots that received either of two treatments: incorporated red clover (Trifolium pratense) residue plus application of compost (`amended soil'), or application of ammonium nitrate fertilizer (`unamended soil'). Soils were analyzed for percent moisture, dissolved organic carbon, conductivity, phenolics, and nutrient content. A trend toward greater incidence of Pythium spp. infection of wild mustard seedlings grown in amended soil was observed during the first 40 days after incorporation (DAI) of red clover and compost, with significant differences (α = 0.05) at two out of four sampling dates in 1997, and four out of four sampling dates in 1998. Incidence of Pythium infection was 10–70% greater in the amended soil treatment during that period. Asymptomatic wild mustard seedlings grown in amended soil were also on average 2.5 cm shorter (α = 0.05) at 5 DAI than those grown in unamended soil in one year out of two. Concentration of phenolic compounds in soil solution was weakly correlated with decreased shoot and root growth (r = 0.50, 0.28, respectively) and increased incidence of disease (r = 0.48) in wild mustard seedlings in one year out of two. Dissolved organic carbon concentration was weakly correlated with increased disease in wild mustard seedlings in both years (r = 0.51, 0.33, respectively). Growth of corn seedlings did not differ between the two soil treatments, suggesting that red clover green manure and compost may selectively reduce density and competitive ability of wild mustard in the field. Bioassay results corresponded well with emergence and shoot weight results from a related field study, indicating that this technique may be useful for screening potential soil treatments prior to field studies.

Northern (Glaucomys sabrinus) and southern (G. volans) flying squirrels occur in Maine, but there is uncertainty about range overlap in southcentral Maine where the southern flying squirrel reaches its geographic range limit. We surveyed flying squirrels on Mount Desert Island (MDI), located along the central Maine coast, to update the current status and distribution of these species. We captured only northern flying squirrels, and populations (≥ 2 individuals) were located in two conifer stands and one mixed conifer-hardwood stand. All three stands were located in relatively older forests, outside a large area burned in a 1947 fire. Tree diameters were similar between trap stations with and without captures, understory density was low overall, and there was a trend of higher seedling density at capture locations. Low understory density may allow squirrels more effective gliding movements between trees, which may enhance predator avoidance. Although the southern flying squirrel was reported from ...

Water motion did not inhibit gamete release in cultures of the coenocytic green alga Bryopsis plumosa (Hudson) C. Agardh; however, the number of gametangia that released gametes increased significantly under transiently calm conditions. This stimulatory effect of calm conditions in the laboratory was found in isolates from two different areas of the Maine coast. The isolates were all monoecious, but strong differences in levels of fertilization, numbers of male and female gametes remaining following fertilization, and levels of polygamy (=zygotes formed by fusions of more than two gametes) were observed among isolates. These data support the hypothesis that organisms with external fertilization are able to sense and respond to water motion in ways that favor reproductive success.

Paleohydrologists sometimes use macrofossils of aquatic vascular plants as one of several independent lines of evidence to infer changes in past lake-levels. Typically, this usage relies on an assumption that the seeds of aquatic species are not dispersed far from the source plants. The water depth over the coring site at the time the seeds were deposited is inferred from the water depth at which the species generally grows today. We determined the water depths at which particular plant-remain types are deposited, and tested whether they can be used successfully as proxy evidence for lake level. The results should aid the interpretation of fossil seeds in paleohydrological studies. A total of 189 surface sediment samples from 13 lakes in Maine and Massachusetts were examined for plant remains, and vegetation was surveyed in the immediate vicinity of each sediment sampling-site. The seeds of some taxa were found in sediment from water-depth ranges much broader than those in which living plants occur. However, in combination, even plant-remain types with broad depth ranges can be used effectively to reconstruct water depth. Presence of plant-remain types can be used to infer water depth regardless of abundance. Test samples indicate that inferring water depth from plant remains works well for shallow, alkaline lakes in New England.

The relationship of soft scald incidence (SSI) with precipitation, temperature, and fruit maturity indicators in ‘Honeycrisp’ apples was examined using 7 years of data in Maine and 6 years in Ontario, Canada. Relative humidity was also examined in Maine. Soft scald incidence was highly variable from year to year ranging from 1% to 85% in Maine and from 0% to 76% in Ontario. In Ontario, SSI was negatively related to soluble solids at harvest (partial r2 = 0.50; P = 0.0041) and negatively related to precipitation during 90 to 120 days from bloom (DFB; partial r2 = 0.28; P = 0.0344). In Maine, SSI was most strongly related to precipitation in the 90 to 120 DFB (partial r2 = 0.53; P = 0.0001), maximum air temperature 60 to 90 DFB (partial r2 = 0.21; P = 0.0001), and number of hours when relative humidity was greater than 85% (partial r2 = 0.11; P = 0.0001).

This study is an extension of the contentanalysis conducted by K. Peirce [(1990) “AFeminist Theoretical Perspective on the Socialization ofTeenage Girls Through Seventeen Magazine,” SexRoles, Vol. 23, pp. 491-500]. Her study examined thecontent of Seventeen magazine for the years 1961, 1972,and 1985, and the impact of the feminist movement fromthe 1960s through the 1980s. The present study explored the content of Seventeen magazine in the years1945, 1955, 1965, 1975, 1985, and 1995 to determine ifthe articles that are presented have changed in responseto the feminist movement from the 1940s to the present day. These results would supportthe contention that there is a relationship between thecontent of Seventeen magazine, in terms of traditionalvs. feminist messages, and the women's movement. However, these changes are slight and still donot reflect the various roles of teenage girls.Implications for further research arediscussed.

The present study builds upon previous research examining variables related to sexual assault. Previous studies have linked sexual aggression with attitudes toward rape as well as hostility toward women. Recent high-profile cases involving athletes and sexual assault have raised questions about the link with athletes. In fact, recent research has suggested that athletes may be more prone to commit rape; however, no study has examined competitiveness. This characteristic, associated with athletes, may predict sexual aggression and help assess why rape is reportedly perpetrated by athletes significantly more frequently than by nonathletes. It may be that individuals with high competitiveness may be more likely to be involved in sexual assaults. Scores on Competitiveness in 104 college men were significantly correlated with reported sexual aggression and athletic participation; however, there was no significant difference between athletes and nonathletes on aggressive sexual behavior. These findings suggest that characteristics of athletes rather than athletic participation alone must be considered further in examining the presumed link between athletes and sexual assault.

Agamospermy, which is almost always associated with polyploidy, is often assumed to reduce variation and foster evolution of microspecies. We tested for the occurrence of microspecies by comparing variation of sexual Amelanchier bartramiana and facultatively agamospermous (asexually seed-producing) Amelanchier laevis. We assessed within- and among-population variation of 222 individuals from six Maine populations of each species for eight morphological variables. Mahalanobis distances between individuals and population centroids and between population centroids and species centroids were used as measures of within- and among-population variation, respectively. Amelanchier bartramiana contains significantly more within- and among-population morphological variation than A. laevis. The two species do not differ in how they partition morphological variation within and among populations. Amelanchier laevis thus does not contain microspecies. Variation within A. laevis may be the result of sexuality, hybridization, polyploidy, and other factors. Key words: Amelanchier, agamospermy, Levene's statistic, microspecies, variation.

Few data currently exist concerning dry bean (Phaseolus vulgaris L.) production systems in which minimum tillage techniques and cover crops are integrated with reduced reliance on chemical inputs. For this reason, we conducted a 2-yr field experiment in central Maine to compare bean growth, N status, and seed yield in two tillage and residue management systems : conventional planting into a tilled seedbed and two herbicide applications vs. no-tillage planting into a rye (Secale cereale L.) cover crop and a single herbicide application. Nitrogen fertilizer was applied at 0, 45, 90, and 135 kg N ha -1 to both systems. In 1990, a year characterized by wet early-season conditions, bean seed yield was 26% lower in the no-tillage-rye mulch system than the conventional system, and increased linearly with N fertilizer rate in both systems. In contrast, in 1991, when early-season rainfall was near normal, yield of the no-tillage-rye mulch system was 23% lower than that of the conventional system without N fertilizer, but increased quadratically to equal yield of the conventional system when N was applied. In both years, seed yield was significantly correlated with early and midseason leaf N concentration and late-season leaf area index. Weed growth was greater in the no-tillage-rye mulch system than the conventional system in 1990, but equally low in both systems in 1991, when an additional cultivation was performed. Because the no-tillage-rye mulch system we examined may reduce bean growth, N status, and yield, we recommend that other management strategies be pursued. Use of legume green manures as N sources in temperate bean production systems merits attention.

Individually quick frozen lowbush (wild) blueberries (Vaccinium angusrifolium) were canned with 0, 1500, or 3000 ppm calcium from chloride or lactate salts and 0, 0.25, or 0.50% citric acid in water. Physical and pH changes were measured at 0, 6, and 12 mo, and sensory evaluations were made at 3 and 9 mo post-canning. Calcium increased firmness and berry calcium content. Calcium chloride and citric acid reduced pH and increased hue angle and off-flavor; calcium lactate increased drained weight and pH but reduced hue. Response surface methodology predicted changes in calcium lactate-treated berries, but not CaCl2-treated berries. Optimal conditions were 1200–1800 ppm calcium lactate at 3–6 mo storage.

A sizeable body of literature has found a surprising amount of agreement among racial and other demographic subgroups on punitive attitudes toward criminals. This consensus has been widely interpreted as evidence for functionalist views of crime and society. Challenging this interpretation, this paper argues that the similar attitudes between the races on punitiveness may in fact mask underlying hostilities and conflicting interests. Analyzing data from the 1987 National Opinion Research Center (NORC) General Social Survey, we find that the punitive attitudes of whites toward criminals are based partly on racial prejudice, while those of blacks are associated with their fear of crime. These results suggest that the consensus found in many previous studies between whites and blacks on punitiveness toward criminals may be apparent rather than real, and that their attitudes toward punitiveness reflect their disparate positions in the social and economic orders.

The objective was to determine the seasonal fluctuations in serum 25-hydroxyvitamin D (25-OHD) in a group of healthy adolescents living in a northern climate. Twenty-three 9- to 11-year-old girls participated in the study from September 2000 to March 2003. Serum 25-OHD and parathyroid hormone levels were measured each September and March. Dietary intake of vitamin D was assessed each summer and winter. Summer-sun exposure was evaluated using reports of time spent outdoors. The mean decrease in serum 25-OHD from September to March was 28%. Vitamin D insufficiency (at least one serum 25-OHD level

We monitored nest boxes during 1997-1999 at Acadia National Park, Mt. Desert Island, ME and at an old-field site in Orono, ME to determine mercury (Hg) uptake in tree swallow (Tachycineta bicolor) eggs, tissues, and food boluses. Also, in 1998-1999 we monitored nest boxes at Grove Pond and Plow Shop Pond at a U.S. Environmental Protection Agency Superfund site in Ayer, MA. We recorded breeding success at all locations. On average among locations, total mercury (THg) biomagnified 2 to 4-fold from food to eggs and 9 to 18-fold from food to feathers. These are minimum values because the proportion of transferable methyl mercury (MeHg) of the THg in insects varies (i.e., 35%-95% of THg) in food boluses. THg was highest in food boluses at Aunt Betty Pond at Acadia, whereas THg in eggs was highest at the Superfund site. A few eggs from nests at each of these locations exceeded the threshold (i.e., 800-1,000 ng/g, wet wt.) of embryotoxicity established for Hg. Hatching success was 88.9% to 100% among locations, but five eggs failed to hatch from 4 of the 11 clutches in which an egg exceeded this threshold. MeHg in feathers was highest in tree swallows at Aunt Betty Pond and the concentration of THg in bodies was related to the concentration in feathers. Transfer of an average of 80%-92% of the Hg in bodies to feathers may have enhanced nestling survival. Residues of Hg in tissues of tree swallows in the Northeast seem higher than those of the Midwest.

Various seafoods were inoculated with six different strains of Escherichia coli at two concentrations (about 10 and 100 cells/g). The samples were then either homogenized or massaged in buffer using sterile sample bags. E. coli concentration was estimated using the standard procedure (MPN) or microbiological test kits, Petrifilm-VRB and Redigel-VRB, incubated at 45.5°C. The correlation (r) between counts generated using the standard procedure and those from massaged samples, using any of the media employed, was slightly higher than 0.60. Despite the low correlations among procedures, massaging and inoculating microbiological test kits will detect accidental fecal contamination (>600 cells/100 g), but can be modified to detect contamination ≤230 cells/100 g. Probabilities involved in estimated fecal coliform concentration, when few colonies are observed, are discussed.

The goal of this study was to determine whether, at different age levels, males cite different bases as reasons for disliking peers. Male preschoolers, primary graders, preadolescents, and young adults were asked to name and give reasons for disliking an actual same-sex peer. Participants from preschool through preadolescence frequently cited aggression and aberrant behavior as reasons for disliking, a finding that suggests that both dimensions serve as major sources of enmity across childhood. Although aggression was not cited frequently by the young adults, aberrant behavior persisted as a significant basis for disliking across all four developmental levels. Lack of general play and rule violation constituted reliable bases for disliking only at the preschool level, whereas lack of help was cited frequently by both the primary-grade and preadolescent participants. The preadolescents and the young adults also specified negative evaluation as a major basis of enmity, whereas lack of genuineness was cited at above-chance levels only by the young adults.

A nonparametric model that relates spruce budworm (Choristoneurafumiferana (Clem.)) and blowdown-caused mortality of balsam fir trees (Abiesbalsamea (L.) Mill.) to individual tree and stand characteristics is presented. Estimation of the annual base-line hazard, λ0(t), also known in epidemiological research as the force of mortality or the instantaneous rate of death, provides an explicit estimate of the rate of change (accelerating or decelerating) of cause-specific mortality during the spruce budworm outbreak. Interpretation of the spruce budworm mortality model indicates that suppressed trees are more likely to survive than the other crown classes. In general, mortality caused by spruce budworm increased with increasing cumulative plot defoliation, increasing spruce (Picea spp.) and balsam fir basal area per hectare, and decreasing hardwood basal area per hectare. Interpretation of the blowdown model indicates that blowdown mortality generally increases with increasing balsam fir, spruce, and percent balsam fir basal areas per hectare and decreasing cumulative plot defoliation.

Three body dimensions (body length, head width, and abdomen width) were used to determine size differences between laboratory-reared and wild populations of Trichogramma minutum Riley. Six separate groups of T. minutum were measured: three groups were from Sitotroga cerealella (Olivier) eggs, two from spruce budworm Choristoneura fumiferana (Clemens) eggs, and one from wild populations of spruce budworm.Female T. minutum from spruce budworm (large host) eggs were significantly larger for all body dimensions than T. minutum from S. cerealella (small host) eggs. Male T. minutum from field-collected spruce budworm eggs were significantly larger for all body dimensions than T. minutum reared for more than one generation in S. cerealella eggs.A significant reduction in female parasitoid size was observed during the initial generations of T. minutum reared in the smaller host (S. cerealella). However, this size reduction was not permanent. Following numerous generations in the S. cerealella host eggs, a significant increase in female parasitoid size was noted within the first generation of T. minutum reared in the spruce budworm host eggs.

Development rates of the parasitoid, Trichogramma minutum Riley, were studied to provide information required in timing field releases of T. minutum for suppression of egg populations of the spruce budworm, Choristoneura fumiferana (Clemens). Development was observed in eggs of 2 host species, C. fumiferana and Sitotroga cerealella (Olivier), at constant temperatures of 14, 21, and 27 °C. Parasitoid development varied directly with temperature. Parasitoids developed more rapidly in eggs of S. cerealella than in those of C. fumiferana. Parasitoid males developed faster than females in some host-temperature treatments. Development of T. minutum is apparently rapid enough to allow progeny of parasitoids released early in the spruce budworm's oviposition period to mature and be available to oviposit in budworm eggs deposited later in the budworm oviposition period. Potential release strategies are discussed.