Gene expression changes in blood RNA after swimming in a chlorinated pool

Exposure to disinfection by-products(DBP) such as trihalomethanes(THM) in swimming pools has been linked to adverse health effects in humans, but their biological mechanisms are unclear. We evaluated short-term changes in blood gene expression of adult recreational swimmers after swimming in a chlorinated pool. Volunteers swam 40 min in an indoor chlorinated pool. Blood samples were drawn and four THM(chloroform,bromodichloromethane, dibromochloromethane and bromoform) were measured in exhaled breath before and after swimming. Intensity of physical activity was measured as metabolic equivalents(METs). Gene expression in whole blood m RNA was evaluated using Illumina Human HT-12v3 Expression-Bead Chip. Linear mixed models were used to evaluate the relationship between gene expression changes and THM exposure. Thirty-seven before-after pairs were analyzed. The median increase from baseline to after swimming were: 0.7 to 2.3 for MET, and 1.4 to 7.1 μg/m~3 for exhaled total THM(sum of the four THM).Exhaled THM increased on average 0.94 μg/m~3 per 1 MET. While 1643 probes were differentially expressed post-exposure. Of them, 189 were also associated with exhaled levels of individual/total THM or MET after False Discovery Rate. The observed associations with the exhaled THM were low to moderate(Log-fold change range:-0.17 to 0.15). In conclusion, we identified short-term gene expression changes associated with swimming in a pool that were minor in magnitude and their biological meaning was unspecific. The high collinearity between exhaled THM levels and intensity of physical activity precluded mutually adjusted models with both covariates. These exploratory results should be validated in future studies.     

Organizational networks in road safety: Case studies of U.S. Vision Zero cities

Objective: Each year, more than 30,000 deaths occur on U.S. roads. Recognizing the magnitude and persistence of this public health problem, a number of U.S. cities have adopted a relatively new approach to prevention, termed Vision Zero (VZ). VZ has been adopted by more than 30?U.S. cities and calls for creating a transportation system that ensures that no road traffic crash results in death or serious injury. A core component of VZ is strong multidisciplinary and multisector stakeholder engagement, and cities adopting VZ often establish a VZ coalition to foster stakeholder collaboration. However, there is little information on the structure, development, and functioning of coalitions working to achieve VZ and on tools available to study and evaluate such coalition functioning. We sought to describe the characteristics of prominent U.S. VZ city coalitions and context surrounding VZ uptake and advancement in these cities. Moreover, we demonstrate use of network analysis as one tool for exploring the structure of interorganizational relationships in coalitions.

Methods: We conducted case studies of 4 prominent U.S. VZ city coalitions in 2017–2018. We summarized coalition members’ characteristics and responses to questions about their cities’ VZ adoption, planning, and implementation. We asked each coalition member to provide information on their contact frequency, perceived productivity, and resource sharing with every other coalition member in their city and used network analysis techniques in 2 cities to understand the structures and relationships in coalitions.

Results: Findings indicated that government agencies generally constituted the majority of coalition members and often played central roles in terms of coalition network contact, productivity, and resource flow. Other emerging similarities regarding coalition establishment and VZ implementation included the need for political support, the importance of formal plan development, and increased collaboration and cooperation among partners.

Conclusions: Organizational network analyses, enriched with coalition member interviews, can elucidate key aspects of coalition creation, attributes, and relationship structure. The case studies of leading VZ coalition networks presented here highlight the use of these tools. Ultimately, understanding associations between VZ network structures and attributes and road safety outcomes could help inform effective coalition adoption, implementation, and maintenance to optimize safety outcomes.     

Human maternal uniparental disomy for chromosome 16 and fetal development

Two severely growth-retarded fetuses found to have maternal uniparental disomy (UPD) for chromosome 16 and trisomy 16 placental mosaicism both had an unfavourable outcome. Antenatally, the first case was complicated by an unexplained raised maternal serum alpha-fetoprotein concentration, preterm premature rupture of the membranes, and growth retardation detectable at 21 weeks' gestation, whilst the other had an unexplained raised maternal serum human chorionic gonadotrophin level, a two-vessel cord on ultrasound, and cessation of growth at 25 weeks. At post-mortem, both babies had an imperforate anus. Fetal maternal UPD may explain the poor outcome that occurs in some cases of confined placental mosaicism for chromosome 16 and is also associated with specific fetal abnormalities.     

Bio-Energy Systems at the Community Level in the South Pacific: Impacts & Monitoring

Read, Sims and Adams (2001) detailed a case study for bio-energy implementation in a notional small Pacific Island and elaborated a theoretical model for assessing and simulating the socio-economic impacts of a particular bio-energy system designed to produce an exportable liquid fuel along with rural electricity supplies. An important conclusion was that there is no silver-bullet ‘one size fits all’ bio-energy system suited to all situations. Moreover, a system appropriate at one place and time may become obsolete with exogenous technological advance and/or as a community advances down its own development pathway. In order to understand how these issues interact in practice, a selected set of implementation projects is reviewed highlighting scale, capacity, community, technology, governmental policy and the concept of critical mass, as factors that are central to the successful development of the bioenergy sector. Through this evaluation, it is shown that: 1.A significant biomass supply resource base often exists locally in the form of agricultural and forestry residues on which modern bioenergy programmes could be initiated. The use of biomass energy flow charts are an important tool for evaluating the potential of local and national resources. 2. Without an integrated multi-disciplinary, multi-sector and whole-systems approach to the implementation of bioenergy schemes, long term success is likely to remain elusive. 3. There is a requirement at the national level for a coordinated approach with strong policy signals that overcome perverse and practical obstacles.     

Seamount endemism questioned by the geographic distribution and population genetic structure of marine invertebrates

Previous studies have suggested that the high diversity associated with the Norfolk seamounts (Southwest Pacific) could reflect endemism resulting from limited dispersal due to hydrological phenomena. Crustaceans of the family Galatheidae are thoroughly studied in the New Caledonia economic zone permitting the analysis of species distribution pattern between the New Caledonia slope and Norfolk ridge seamounts. This analysis has shown that, qualitatively, the same species are sampled on seamounts and on the New Caledonia slope. Local endemism was never detected. However, on each seamount, and therefore on a small surface, a very high number of species are usually sampled, suggesting that seamounts are biodiversity hot spots. Then, to evaluate whether the seamounts constitute patches of isolated habitat, we explore the pattern of genetic diversity within several species of crustaceans and gastropods. Analysis of the intra-specific genetic structure using the mitochondrial marker COI reveals that populations of two Galatheidae species (Munida thoe and Munida zebra), polymorphic for this marker, are genetically not structured, both among seamounts and between the seamounts and the island slope. The genetic structure over a similar sampling scheme of two Eumunida species (Chirostylidae, the sister family of Galatheidae) and a planktotrophic gastropod (Sassia remensa) reveals a similar pattern. Population structure is observed only in Nassaria problematica, a non-planktotrophic gastropod with limited larvae dispersal. Thus, the limitation of gene flow between seamounts appears to be observed only for species with limited dispersal abilities. Our results suggest that the Norfolk seamounts rather than functioning as areas of endemism, instead, may be highly productive zones that can support numerous species in small areas.     

Stream ecosystem response to limestone treatment in acid impacted watersheds of the Allegheny Plateau.

Restoration programs are expanding worldwide, but assessments of restoration effectiveness are rare. The objectives of our study were to assess current acid-precipitation remediation programs in streams of the Allegheny Plateau ecoregion of West Virginia (USA), identify specific attributes that could and could not be fully restored, and quantify temporal trends in ecosystem recovery. We sampled water chemistry, physical habitat, periphyton biomass, and benthic macroinvertebrate and fish community structure in three stream types: acidic (four streams), naturally circumneutral (eight streams), and acidic streams treated with limestone sand (eight streams). We observed no temporal trends in ecosystem recovery in treated streams despite sampling streams that ranged from 2 to 20 years since initial treatment. Our results indicated that the application of limestone sand to acidic streams was effective in fully recovering some characteristics, such as pH, alkalinity, Ca2+, Ca:H ratios, trout biomass and density, and trout reproductive success. However, recovery of many other characteristics was strongly dependent upon spatial proximity to treatment, and still others were never fully recovered. For example, limestone treatment did not restore dissolved aluminum concentrations, macroinvertebrate taxon richness, and total fish biomass to circumneutral reference conditions. Full recovery may not be occurring because treated streams continue to drain acidic watersheds and remain isolated in a network of acidic streams. We propose a revised stream restoration plan for the Allegheny Plateau that includes restoring stream ecosystems as connected networks rather than isolated reaches and recognizes that full recovery of acidified watersheds may not be possible.     

Dominance and reproductive behavior of wild house mice in a seminatural environment correlated with T-locus genotype

Summary Behavior of mice whose T-locus genotype was either +/+ or +/t was observed in a seminatural environment. Heterozygous females were less likely to be dominant, less likely to go into behavioral estrus, and less likely to become pregnant than were +/+ females. The relative fitness of +/t as compared with +/+ females was 0.32:1.00. In contrast, +/t males produced 35% more young than did +/+ males. The higher fitness of +/t males was primarily due to a greater production of young on the part of +/t as compared with +/+ subordinate males. Little evidence was found under these naturalistic conditions, of non-random mating with respect to T-locus genotype. The indication of overdominance for +/t males makes it unlikely that heterozygote disadvantage will be sufficient to account for the frequency of t-alleles in natural populations.     

Estimates from a consumer demand system: implications for the incidence of environmental taxes

Most studies suggest that environmental taxes are regressive, making them less attractive policy options. We consider the distributional effects of a gasoline tax increase using four incidence measures and under three scenarios for gas tax revenue use. To incorporate behavioral responses we use Consumer Expenditure Survey data to estimate a consumer demand system that includes gasoline, other goods, and leisure. Our estimates confirm that when revenues are not recycled, a gasoline tax is regressive. Use of incidence measures that ignore demand responses, however, will substantially overstate this regressivity. In contrast, the differences between the equivalent variation and easier-to-implement consumer surplus measures are relatively small. In addition, our results suggest that using the additional gas tax revenue to fund labor tax cuts makes the policy substantially less regressive while using the revenue to fund lump-sum transfers actually makes it progressive.     

Greening the Congressional record: environmental social movements and expertise-based access to the policy process

ABSTRACT

A new dataset of organizational testimony at U.S. Congressional hearings on environmental protection is used to examine how social movement organizations use issue expertise to gain access to the policy process. Environmental movement organizations (EMOs) are shown to testify in greater numbers at hearings that consider proposed legislation, compared to hearings that are exploratory or investigatory in nature. The increased representation at legislative hearings is unique to EMOs; other kinds of organizations do not obtain similar increases in legislative access. These findings suggest that, due to their scientific expertise and perceived legitimacy, EMOs receive privileged access to the policy process relative to other organizations affected by environmental policy and at a later stage than has been proposed by prior work examining social movement access to the policy process.     

Lake sediments record sensitivity of two hydrologically closed upland lakes in Mexico to human impact

We provide evidence of rapid, recent environmental change in two lakes in the highlands of central Mexico. Multiple sediment cores were obtained from Lago de Zirahuén (Michoacán) and Laguna de Juanacatlán (Jalisco). Analysis of diatom assemblages, magnetic susceptibility, and metal concentrations was carried out, with the chronology provided by 210Pb dating, 14C dating, and tephrochronology. There is evidence of catchment disturbance during the colonial period in both basins, but the most striking feature at both sites is the rapid change in diatom assemblages during the last 20 y, indicating the onset of eutrophication. Limnological data from Lago de Zirahuén support this interpretation, although none are available from Laguna de Juanacatlán. Paleolimnology is a powerful tool in tracking recent change, particularly in the absence of regular limnological monitoring programs. These lakes appear to be highly sensitive to changes in catchment exploitation, which must be considered in future drainage basin management.