Social Capital in an Outdoor Recreation Context

This study examined social capital development in three all-terrain vehicles (ATV) clubs in Maine using an adapted version of Lin’s (2001) social capital theory model. The structural components of social capital identified included collective assets and individual assets in the form of normative behavior and trust relationships. Also identified were counter-norms for individual ATV riders identified as having divergent norms from club members. The second component of social capital is access to and mobilization of network contacts and resources. Access networks in the context of the ATV clubs studied were identified as community and landowner relations while mobilization of resources was existent in club membership attempts toward self-governance and efforts of the statewide “umbrella” organization. Instrumental outcomes benefit society and expressive outcomes benefit the individual. Both types of returns are present in the data suggesting that ATV clubs are creating social capital. This is important information to clubs who desire to market themselves, improve their reputations, and enhance their volunteer association. It is of further interest to state governments who fund clubs through trail grants as proof that a return on investment is being realized. Theoretical and applied implications for these and other types of recreation-based volunteer associations (e.g., clubs, friends groups, advocacy groups) are presented.     

活性炭纤维低温脱除模拟烟气中的VOC

采用H2O2浸渍的修饰方法对ACF进行化学改性,并利用氮吸附等温线和XPS（X-ray photoelectron spectroscopy）的方法对ACF样品进行表征。通过在反应床上开展吸附实验,由此测定改性前后ACF脱除VOC（甲苯作为VOC的代表物）的效果,同时考察氧气、温度、水蒸气等因素对ACF脱除甲苯的影响。研究发现,改性使得ACF样品比表面积和孔容略有降低,但表面含氧官能团含量增加,吸附甲苯的能力也因此增强。当模拟烟气中O2浓度为5%时,ACF脱除VOC效果达到最佳,超过5%之后,氧的促进效果不再明显;温度40℃为最佳吸附温度;当烟气中加入水蒸气时,ACF对VOC的脱除效率降低。     

Analyzing maps of dispersal around a single focus

The spatial pattern of organisms may be used to characterize their dispersal, quantify spread or estimate the point of introduction of an alien species. Their distribution may be represented by maps of individuals, or by counts or by presence/absence at known positions within a sampled area. The problems and relative merits of these different forms of data for spatial inference are discussed. Three datasets concerning dispersal from a single focus are analyzed: counts of aphids, Rhopalosiphum padi and Sitobion avenae, on barley plants, Hordeum vulgare, grown in experi- mental trays; mapped locations of couch grass, Elymus repens, tillers within plots of a field experiment; locations of sightings of the lupin aphid, Macrosiphum albifrons, as it invaded Great Britain between 1981 and 1984. A method for generating maps from counts is proposed to overcome problems caused by recording imprecision. Several statistics are used to quantify dispersal and spatial pattern in the experimental data and together provide a clear picture of the spatial pattern observed; they enabled several effects of the experimental treatments to be identified. The value of the statistics are compared. Estimates of the source of the lupin aphid invasion are obtained using the backtracking methods of Perry (1995b) and do not contradict previous suggestions.     

Nitrate Artifacts during PM25 Sampling in the South Coast Air Basin of California

ABSTRACT

In February 1993, the South Coast Air Basin (SCAB) was redesignated as a “serious” nonattainment area for PM10. To improve the understanding and characterization of fine particulate matter in the SCAB, the South Coast Air Quality Management District (SCAQMD) initiated a comprehensive PM₁₀ Technical Enhancement Program (PTEP). Using enhanced PTEP monitors (specially designed multichannel/multifilter samplers), a one-year fine particulate matter (PM) monitoring program was initiated in January 1995. As part of the special monitoring program, nitric acid, ammonia, and speciated PM₁₀ and PM_2.5 concentrations were measured at five locations in the SCAB (downtown Los Angeles, Anaheim, Diamond Bar, Fontana, and Rubidoux) and at one background station (San Nicolas Island). The PM2.5 data are the first spatially resolved speciated data collected in the SCAB on an annual basis. Within the SCAB, where nitrate is a major component of PM_2.5, nitrate losses have been documented. The spatial and temporal variations of the nitrate losses during PM_2.5 sampling and the uncertainties of the nitrate losses are discussed. Significant losses occur at a low mass range, between 10 and 50 ìg/m³. Significant gains occur at an even lower mass range of less than 30 ìg/m³. On an annual average basis, nitrate losses vary between 1.25 and 2.32 ìg/m³ and the SCAB-wide average value of nitrate loss is 1.8 ìg/m³ based on five PTEP stations in the SCAB. The maximum nitrate losses for each station vary from 6.4 ìg/m³ to 22.5 ìg/m ³. Theoretical prediction of the sampling efficiency of the nitrate during PM_2.5 sam - pling was compared with the PTEP data. In general, theoretical prediction was in good agreement with measured values.     

Predictability of clinical assessments for driving performance

PROBLEM: As the number of older drivers grows, it is increasingly important to accurately identify at-risk drivers. This study tested clinical assessments predictive of real-time driving performance. METHOD: Selected assessment tools considered important in the identification of at-risk older drivers represented the domains of vision, cognition, motor performance, and driving knowledge. Participants were administered the battery of assessments followed by an on-road test. A univariate analysis was conducted to identify significant factors (<.05) to be included in a multivariate regression model. RESULTS: Assessments identified as independently associated with driving performance in the regression model included: FACTTM Contrast sensitivity slide-B, Rapid Pace Walk, UFOV rating, and MMSE total score. DISCUSSION: The domains of vision, cognitive, and motor performance were represented in the predictive model. SUMMARY: Due to the dynamic nature of the driving task, it is not likely that a single assessment tool will identify at risk drivers. IMPACT ON INDUSTRY: By standardizing the selection of clinical assessments used in driving evaluations, practitioners should be able to provide services more efficiently, more objectively, and more accurately to identify at-risk drivers.     

Polybrominated diphenyl ether in sewage sludge in Germany

Sewage sludge samples from 11 municipal waste water treatment plants in Germany were collected from March 2002 to June 2003. Total Tri- to HpBDE concentrations (sum of significant congeners BDE 28, 47, 99, 153, 154 and 183) ranged from 12.5 to 288 (median 108) and DeBDE (BDE 209) concentrations from 97.1 to 2217 (median 256) ng/gd.m. BDE 209 dominated the congener profile. A significant change of the Tri- to HpBDE congener profile (% of total BDE 28, 47, 99, 153, 154, 183 without 209) in sludge from different stages of the waste water treatment process (primary sludge, secondary excess sludge and (dewatered) digested sludge), indicating a degradation of DeBDE to these congeners, was not observed.     

Disturbance by ice and life-history adaptations of the seagrassZostera marina

The formation of winter ice, and its movement with the tides, has had a major influence on the life-history parameters of shallow-water populations of the rhizomatous marine angiosperm eelgrass (Zostera marina) in Nova Scotia, Canada. In this region, and annual form of eelgrass inhabits intertidal and shallow subtidal mudflats and a perennial form is common in subtidal areas. Where lowtide water depth was greater than winter ice thickness (25 cm), ice movement removed much of the aboveground biomass from perennial ramets, but did not influence the density of ramets. Measurements of primary production showed that perennial plants allocated a greater proportion of their total production to below-ground structures than measured in all previous studies on eelgrass. Thus perennials are well anchored in the sediment, are more able to withstand removal by ice, and have reserves available for production of new leaves when ice melts. In the spring, seed germination was greatest in areas where ice had removed whole plants (or their aboveground parts) than among mature ramets which had survived winter intact. Survival of seedlings (new genets) was not affected by shading from the adult canopy, but a shading experiment showed that competition for light with mature ramets had a significant negative effect on morphology, growth and the allocation of seedling biomass to below-ground parts, thus reducing the ability of new genets to survive ice disturbance in the next winter. The annual form ofZ. marina was restricted to areas where low tide water depth was much less than winter ice thickness. Annual plants did not survive winter, had small investment in below-ground parts and high reproductive effort, and overwintered as seeds. The genetic status of the two forms and the restriction of the annual to very shallow water are discussed in the light of previous work on eelgrass     

Changes in the spermatophoric plasma during spermatophore development and during the spermatophoric reaction in the giant octopus of the north pacific,Octopus dofleini martini

Concentrations of Na, K, Cl, Ca and Mg were measured in the spermatophoric plasma and certain other body fluids of Octopus dofleini martini. The most striking change associated with maturation and passage of the spermatophore in the male reproductive tract, was a decline in the concentration of NaCl in the spermatophoric plasma. This was completely reversed during the spermatophoric reaction owing to influx of salt from the seawater. The outer tunic of a spermatophore undergoing spermatophoric reaction is also permeable to other substances. It allows an influx of inorganic phosphate and glucose, and an efflux of organically bound nitrogen, carbohydrate and aminosugar.     

Changing lobster abundance and the destruction of kelp beds by sea urchins

In a study area in Nova Scotia, Canada, abundance of the lobster Homarus americanus decreased by nearly 50% in 14 years. The lobster is a major predator of sea urchins, and during the past 6 years the sea urchin Strongylocentrotus droebachiensis has destroyed 70% of the beds of Laminaria spp. in the area. Implications for management are discussed.