Detecting state changes for ecosystem conservation with long-term monitoring of species composition.

Effective conservation requires an understanding not only of contemporary vegetation distributions in the landscape, but also cognizance of vegetation transitions over time with the goal of maintaining persistence of all states within the landscape. Using a state and transition model framework, we investigated temporal transitions over 31 years in species composition among five upland swamp vegetation communities in southeastern Australia. We applied fuzzy clustering to document transitions across communities; evaluated the resilience and resistance of communities to change; and explored the relationship between ecosystem states and major environmental factors posited to structure the system. We also evaluated the predictive ability of an established vegetation dynamics model. We found that community composition remained stable or underwent reversible or directional transitions depending on the vegetation type. Wetter communities (Ti-tree thicket and Cyperoid heath) were more stable (i.e., resistant) while drier communities showed a greater propensity to transition (i.e., had lower resistance) under the observed disturbance regime (low variance fire intervals). The resilience of drier communities differed under this regime, with Banksia thicket showing reversible compositional change, while Restioid heath and Sedgeland showed directional change. In accord with an established conceptual model, we found that communities were distributed along a hydrological gradient. In addition, vegetation structure, along with light penetration to ground level, differentiated communities. However, internal dynamics of drier communities were complex: differences in fire regime (penultimate fire interval in 2014 and number of fires since 1965) were unable to predict differences in community membership among sites. Aspects of the fire regime are expected to be more important predictors if fire intervals vary more strongly among sites in the future. Fuzzy clustering of compositional data allows managers to track community transitions over time and facilitates planned interventions for conservation purposes.

Arrival order among native plant functional groups does not affect invasibility of constructed dune communities.

Different arrival order scenarios of native functional groups to a site may influence both resource use during development and final community structure. Arrival order may then indirectly influence community resistance to invasion. We present a mesocosm experiment of constructed coastal dune communities that monitored biotic and abiotic responses to different arrival orders of native functional groups. Constructed communities were compared with unplanted mesocosms. We then simulated a single invasion event by bitou (Chrysanthemoides monilifera ssp. rotundata), a dominant exotic shrub of coastal communities. We evaluated the hypothesis that plantings with simultaneous representation of grass, herb and shrub functional groups at the beginning of the experiment would more completely sequester resources and limit invasion than staggered plantings. Staggered plantings in turn would offer greater resource use and invasion resistance than unplanted mesocosms. Contrary to our expectations, there were few effects of arrival order on abiotic variables for the duration of the experiment and arrival order was unimportant in final community invasibility. All planted mesocosms supported significantly more invader germinants and significantly less invader abundance than unplanted mesocosms. Native functional group plantings may have a nurse effect during the invader germination and establishment phase and a competitive function during the invader juvenile and adult phase. Arrival order per se did not affect resource use and community invasibility in our mesocosm experiment. While grass, herb and shrub functional group plantings will not prevent invasion success in restored communities, they may limit final invader biomass.

The use of a range of ultrasound frequencies to reduce colouration caused by dyes.

The formation of hydrogen peroxide and the degree of decolourisation of six different dyes as a result of sonication over several ultrasonic frequencies (20, 40, 380, 512, 850, 1,000 and 1,176 kHz) was investigated and correlated. It was found that the highest levels of hydrogen peroxide and also the greatest amount of decolourisation occurred at 850 kHz. 380 and 512 kHz also resulted in some decolourisation, however higher and lower ultrasonic frequencies were not effective.

Assessing the effect of different ultrasonic frequencies on bacterial viability using flow cytometry.

AIMS: This research investigated the effect of sonication at frequencies of 20, 40 and 580 kHz and approximately the same acoustic intensity on the viability and declumping of two micro-organisms (Escherichia coli and Klebsiella pneumonia). METHODS AND RESULTS: Two analytical methods were employed; viable plate counts (CFU ml−1) and flow cytometry to identify and quantify both live/viable and dead bacteria in the bulk liquid. Flow cytometry results for E. coli and Kl. pneumonia indicated a high sensitivity to 20 and 40 kHz frequency with a continuous decrease in the viable cells and an increase in dead cells during experiments. In contrast, results using the higher frequency of 580 kHz indicate predominantly deagglomeration of bacterial clumps rather than cell membrane disruption (Joyce et al. 2003). Results indicate a good correlation between flow cytometry and viable plate count methodology. CONCLUSIONS: Sonication has two different effects on bacteria (i) inactivation and (ii) declumping; however, the scale of these effects is dependent on intensity and frequency. Flow cytometry provides a method to distinguish between and quantify the effects through the observation of two subpopulations: (i) live/viable and (ii) dead bacterial cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Treatment using power ultrasound has been shown to have a significant impact on microbial activity. This is the first time a study has compared the influence of a range of different frequencies, but at similar power settings on the survival of bacteria in phosphate buffer saline (PBS). This work is of importance for applications where ultrasound has been considered for use in industry as a means of disinfection including the treatment and pretreatment of water and also for the sterilization of liquid foods.

Persistent effects of underground longwall coal mining on freshwater wetland hydrology.

More than half of global wetlands have been lost because of anthropogenic disturbance, with the trend of decline continuing in the 21st century. While much of this loss relates to changes in surface flows, groundwater is also critical to sustaining wetland hydrology. Underground longwall mines extract coal seams, in turn fracturing the overlying stratigraphy, influencing aquifer connectivity and affecting surface flows via subsidence disturbance. Crucially, this subterranean disturbance may disrupt the hydrological processes that sustain freshwater wetlands at the surface. Here we present a new designed empirical study that compares the persistence of soil moisture after a rainfall event in wetlands subject to underground longwall coal mining to that in unmined reference wetlands. Accelerated Failure Time models showed that mined wetlands were persistently drier, retained water for shorter durations and exhibited less spatial differentiation than unmined wetlands. This quantitative evidence of severe, persistent hydrological change following resource extraction reinforces earlier observations and has important implications for biodiversity and provision of ecosystem services to a large urban population. If Ecologically Sustainable Development (ESD) outcomes and effective deployment of the mitigation hierarchy are to be achieved in line with current legislative and policy paradigms, our results highlight the need for more emphasis on impact avoidance and minimisation than restoration or offsetting to protect water and biodiversity values. Given severe constraints on restoration success, greater emphasis on avoidance in mine design and approval processes offers realistic opportunities for an improved balance between sustaining irreplaceable public assets and short-term benefits from non-renewable resource extraction.

Cancer by county: new resource for etiologic clues.

Mapping of U. S. cancer mortality by county has revealed patterns of etiologic significance. The patterns for bladder cancer in males point to industrial determinants: some are known (chemical manufacturing) but others (automobile and machinery manufacturing) represent new leads for epidemiologic study. By contrast, the geographic clusters of high rates of stomach cancer in both sexes are consistent with ethnic susceptibility.

Chemistry of antibody binding to a protein.

The chemistry of antibody recognition was studied by mapping the antigenicity of the protein myohemerythrin with peptide homologs of the protein sequence. The results suggest that the entire protein surface is antigenic, but the probability of there being antibodies to a given site is influenced by local stereochemistry. Although accessible to an antibody binding domain, the least reactive positions cluster in the most tightly packed and least mobile regions and are closely associated with narrow, concave grooves in the molecular surface containing bound water molecules. The most frequently recognized sites form three-dimensional superassemblies characterized by high local mobility, convex surface shape, and often by negative electrostatic potential.

The enhancement and scale up of the extraction of anti-oxidants from Rosmarinus officinalis using ultrasound.

The aim of this study was to examine the effect of ultrasound on the solvent extraction of anti-oxidants from the rosemary herb and to scale up the ultrasonic extraction process. The anti-oxidants of interest were identified using HPLC. Results indicated that, compared with conventional solvent extraction, the use of ultrasound gives a more effective extraction at lower temperatures with less dependence on the extraction solvent employed and that scale up of the process is possible.

A reactor designed for the ultrasonic stimulation of enzymatic esterification.

A laboratory scale ultrasonic flow reactor capable of enhancing enzymatic reactions has been built and characterized using as a model reaction the enzymatic synthesis of isoamyl acetate using Lipozyme 435 immobilized on a macroporous anion exchange resin. The efficiency of the reactor was determined in relation to ultrasonic power density (measured by 4-nitrophenol dosimetry), position of ultrasonic horn and temperature. The results show that ultrasound can enhance the process efficiency and also reduce the reaction time.

Ultrasonic, hydrodynamic and microwave biodiesel synthesis - A comparative study for continuous process.

At this time biodiesel appears to be a viable proposition as a renewable energy source and an alternative to fossil-based fuels. Following many years of research, the use of process intensification techniques for the production of biodiesel is well documented. This work has focused more on a study of biodiesel production using continuous flow systems assisted by acoustic cavitation (ultrasonic or hydrodynamic) or microwaves. The target end user is the small or medium farm where such equipment could provide sufficient fuel for on-site agricultural machinery using renewable or waste green materials produced on site.

Associations of cancer mortality with halomethanes in drinking water.

Associations between site- and sex-specific county cancer mortality rates and levels of trihalomethanes (THM's) in drinking water were examined after adjustment of rates for the influence of multiple socioeconomic, industrial, and demographic factors. U.S. counties with sampled supplies were grouped by percent of the county population receiving water from the supply, as well as by region of the country. For two sites (bladder and lung), county rates were also adjusted for the activity level in specific high-risk industries. Positive correlations with THM levels were observed for several cancers, including bladder and brain cancers in both sexes, and non-Hodgkin's lymphoma and kidney cancer in males. Stomach cancer in females showed a negative association. Bladder cancer mortality rates showed the strongest and most consistent association with a THM exposure index, after control for differences in social class, ethnic group, urban versus rural residence, region of the United States, and industrialization of the county. These ecologic associations suggested that further evaluation in analytic investigations is warranted.

Occupation and lung cancer risk among New Jersey white males.

The association of occupation with lung cancer risk was examined in a case-control study conducted in six areas of New Jersey. The study included 763 white males with incident histologically confirmed primary cancer of the trachea, bronchus, and lung and 900 general population white male controls selected from driver's license and death certificate files. Altogether, 27 employment categories had a smoking-adjusted odds ratio (OR) of 1.3 or greater; five of these with significantly high OR contributed to an occupational population attributable risk of 13%. Masons and tilesetters; janitors and cleaners; printing workers; and trucking service, warehousing, and storage workers had significantly high risks overall and for longer durations of employment. Shipbuilding workers had significantly high risk overall and for short duration of employment. Although the excess risk for all shipbuilding workers was primarily among those with reported exposure to asbestos, the risk was also high among welders, burners, sheet metal workers, and boilermakers with no reported asbestos exposure.

Statistically adjusted estimates of geographic mortality profiles.

The spatial variation of site-specific cancer mortality rates at the county or state economic area level can provide a) insights into possible etiologic factors and b) the basis for more detailed epidemiologic studies. One difficulty with such studies, especially for rare cancer types, is that unstable local area rate estimates, resulting from small population sizes, can obscure the underlying spatial pattern of disease risk. This paper presents a methodology for producing more stable rate estimates by statistically weighting the local area rate estimate toward the experience at the national level. The methodology is illustrated by the analysis of the spatial variation of two cancer types, bladder and lung, for U.S. white males over the three decades 1950-79.

Case-control study of bladder cancer in New Jersey. I. Occupational exposures in white males.

The occupational bladder cancer risk for New Jersey white males was estimated with the use of both industry-job title-based and exposure-based analyses of data from 658 incident cases and 1,258 general population controls. The overall bladder cancer risk attributable to occupational exposures was estimated as 20-22%. A wide variety of employment categories and exposures contributed to this risk. Odds ratios were significantly high for employment as garage and gas station workers and food counter workers and/or cooks and for exposure to leather, rubber, paint, printing ink, and other organic compounds. Odds ratios for textile mill workers, chemical workers, and metal workers for the a priori high-risk employment category and odds ratios for those exposed to dyes, chlorinated compounds, and rubber showed significant differences between younger and older subjects. Bladder cancer risk associated with occupational exposures was not limited to persons with initial exposures before 25 years of age. However, there was significantly decreasing risk for bladder cancer with increasing age at first exposure for chemical workers and metal workers and for the a priori high-risk materials and metals. Drivers and/or deliverymen and miscellaneous laborers had significantly increasing bladder cancer risk with increasing duration of employment.

Bladder cancer, drinking water source, and tap water consumption: a case-control study.

Data from a population-based case-control interview study of incident bladder cancer in 10 areas of the United States were used to estimate relative risks among white men (2,116 cases, 3,892 controls) and women (689 cases, 1,366 controls) according to beverage intake level and type of water source. Individual year-by-year profiles of water source and treatment were developed by linking lifetime residential information with historical water utility data from an ancillary survey. Risk of bladder cancer increased with intake level of beverages made with tap water. The odds ratio (OR) for the highest vs. lowest quintile of tap water consumption was 1.43 [95% confidence interval (CI) = 1.23, 1.67; chi 2 for trend = 26.3, P less than .001]. The risk gradient with intake was restricted to persons with at least a 40-year exposure to chlorinated surface water and was not found among long-term users of nonchlorinated ground water. The ORs for the highest vs. lowest quintiles of tap water intake were 1.7 and 2.0, respectively, among subjects with 40-59 and greater than or equal to 60 years' exposure. Duration of exposure to chlorinated surface water was associated with bladder cancer risk among women and nonsmokers of both sexes. Among non-smoking respondents with tap water consumption above the population median, the OR increased with exposure duration to a level of 3.1 (CI = 1.3, 7.3; chi 2 for trend = 6.3, P = .01) for greater than or equal to 60 years of residence at places served by chlorinated surface water (vs. non-chlorinated ground water users). These results extend findings of earlier epidemiologic studies and are consistent with environmental chemistry and toxicologic data demonstrating the presence of genotoxic by-products of chlorine disinfection in treated surface waters.

Dietary carotene and vitamin A and risk of lung cancer among white men in New Jersey.

A population-based incident case-control study of lung cancer in white males was conducted during 1980-81 in six high-risk areas of New Jersey. Interviews were completed with 763 cases and 900 controls or with their next of kin. In order to assess whether dietary intake of carotene, preformed retinol, or total vitamin A modified the risk of lung cancer, subjects were asked about their usual frequency of consumption, several years earlier, of 44 food items, which provides 83% of the vitamin A in the American diet, and about their use of vitamin supplements. The men in the lowest quartile of carotene intake had 1.3 the risk (P-value for trend = .05) of those in the highest quartile after adjustment was made for smoking duration and intensity and education. No association was seen for retinol (P-value for trend = .11) or total vitamin A (P-value for trend = .30). The inverse association between carotene intake and lung cancer was most compelling for squamous cell carcinoma, with the smoking-and education-adjusted risk of those in the lowest quartile reaching 1.4 (P-value for trend = .03) the risk of those men in the highest quartile. Risk of lung adenocarcinoma was not related to carotene intake. The reduction in risk of squamous cell lung cancer with increasing carotene intake was noted in pipe and cigar smokers and cigarette smokers of different intensities. Among nonsmokers adenocarcinoma predominated. The inverse association between carotene and risk of squamous cell lung cancer was not especially strong or graded in response; but it was consistent and could be noted in each stratum when the subjects were divided by education, age, or mode of interview (direct vs. next of kin). The results of the other 4 case-control and 3 cohort studies that have looked at diet and risk of lung cancer are not consistent, and the question whether dietary carotene or total vitamin A reduces the risk of lung cancer is not yet resolved.

Motor exhaust-related occupations and bladder cancer.

The relationship between employment in occupations with potential exposure to motor exhaust and bladder cancer risk was examined based on interviews conducted with 1909 white male bladder cancer patients and 3569 population controls during the National Bladder Cancer Study, a population-based, case-control study conducted in ten areas of the United States. Our findings indicated that males usually employed as truck drivers or deliverymen have a statistically significant, 50% increase in risk of bladder cancer. Overall, a statistically significant trend in risk with increasing duration of truck driving was observed. This trend was particularly consistent for drivers first employed at least 50 years prior to diagnosis. Of these, truck drivers employed 25 years or more experienced a 120% increase in risk. Elevations in risk were also suggested for taxicab and bus drivers. These findings, coupled with experimental evidence of the mutagenicity and possible carcinogenicity of motor exhaust emission particulates, suggest a role for motor exhaust exposure in human bladder carcinogenesis.

Case-control study of residential radon and lung cancer among New Jersey women.

To evaluate the association of indoor radon exposure with lung cancer risk, yearlong alpha track detector measurements of radon were conducted in dwellings which had been occupied for at least 10 years by 433 New Jersey female lung cancer cases and 402 controls who were subjects in a larger population-based study. Adjusted odds ratios were 1.1 (90% confidence interval, 0.79-1.7), 1.3 (90% confidence interval, 0.62-2.9), and 4.2 (90% confidence interval, 0.99-17.5) for exposures of 1.0-1.9, 2.0-3.9, and 4.0-11.3 pCi/liter, respectively, relative to exposures of less than 1.0 pCi/liter, showing a significant trend (1-sided P = 0.04) with increasing radon concentration. The trend was strongest among light smokers (less than 15 cigarettes/day, 1-sided P = 0.01). The trend for lung cancer risk with estimated cumulative radon exposure was slightly weaker (1-sided P = 0.09). The increase in relative risk for each unit of cumulative exposure, 3.4% (90% confidence interval 0.0-8.0%) per working level month, was consistent with the range of 0.5-4.0% per working level month generally reported for underground miner studies, supporting the extrapolation of the occupational data to the residential setting. However, the possibility of selection biases, the small number of high exposures, and other uncertainties necessitate caution in interpretation of these data.

Occupational risk factors for laryngeal cancer on the Texas Gulf Coast.

Analyses are reported from a case-control interview study of incident laryngeal cancer on the Gulf Coast of Texas. Study subjects were 183 white men with squamous cell carcinoma of the larynx and 250 frequency matched controls. Occupational exposures were examined controlling for potential confounding by cigarette smoking and alcohol consumption. Significantly elevated risks were seen for men employed in the public services industry [transportation, communication, utilities, sanitary service; relative risk (RR), 1.6]; in metal fabricating (RR, 2.1), construction (RR, 1.7), and maintenance (RR, 2.7) occupations; and for workers potentially exposed to paint (RR, 1.8) and diesel or gasoline fumes (RR, 1.5). Elevated risks of border-line significance were seen for men employed as woodworkers/furniture makers (RR, 8.1) and for those with occupational exposure to asbestos (RR, 1.5). When asbestos was categorized by intensity of exposure, a significant positive gradient was found.

The relation of passive smoking to lung cancer.

To evaluate the role of passive smoking in the development of lung cancer among nonsmokers, data were pooled from three large incident case-control interview studies. Ninety-nine lung cancer cases and 736 controls never used any form of tobacco. Overall the adjusted odds ratio for lung cancer among nonsmokers ever living with a smoker was 0.8 (95% confidence interval, 0.5-1.3) rising to 1.2 among those exposed for 40 or more years. Persons living with a spouse who smoked cigarettes were at increased risk (adjusted odds ratio, 1.5; 95% confidence interval, 0.8-2.8). When adjusted for age and gender, there was a significant trend in risk with increasing amounts smoked per week by the spouse (P = 0.05) and with cumulative pack-years of exposure (P = 0.03). This effect was limited to females, especially older women whose husbands were heavy smokers. The elevated risk associated with spouse smoking was restricted to squamous and small cell carcinomas (odds ratio, 2.9; 95% confidence interval, 0.9-9.3), which provides additional evidence linking passive smoking to lung cancer.