Longer-term effects of Washington, DC, law on drivers' hand-held cell phone use

OBJECTIVES: To determine whether the substantial short-term declines in drivers' use of hand-held phones achieved in the District of Columbia (DC) were sustained 1 year after a ban. METHODS: Drivers' daytime hand-held cell phone use was observed in DC and nearby areas of Virginia and Maryland, states without bans. Observations were conducted several months before the ban, shortly after, and 1 year later. The number of vehicles observed in all three surveys combined was 51,945 in DC, 36,796 in Maryland, and 43,033 in Virginia. RESULTS: The rate of talking on hand-held phones declined significantly from 6.1 percent before the law to 3.5 percent shortly after; when measured 1 year later, use was 4.0 percent, still significantly lower than baseline. Based on increases in rates of talking on hand-held phones in Maryland and Virginia, longer-term phone use in DC was estimated to be 53 percent lower than would have been expected without the ban. Declines in DC were identified for drivers of vehicles registered in all three jurisdictions. CONCLUSIONS: In DC, there was an initial decline of about 50 percent in drivers talking on hand-held cell phones following a ban, and this decline was sustained about 1 year later. After a similar ban in New York, there was an initial decline in phone use comparable with the initial decline in DC, but the decline a year after the New York ban took full effect was only about 21 percent and not statistically significant. The potential difference in sustained effectiveness for the DC ban may reflect tougher enforcement in DC. Even if full compliance with hand-held phone bans can be achieved, the risks from drivers' use of hands-free phones will remain.     

Featured Collection Introduction: Connectivity of Streams and Wetlands to Downstream Waters

Connectivity is a fundamental but highly dynamic property of watersheds. Variability in the types and degrees of aquatic ecosystem connectivity presents challenges for researchers and managers seeking to accurately quantify its effects on critical hydrologic, biogeochemical, and biological processes. However, protecting natural gradients of connectivity is key to protecting the range of ecosystem services that aquatic ecosystems provide. In this featured collection, we review the available evidence on connections and functions by which streams and wetlands affect the integrity of downstream waters such as large rivers, lakes, reservoirs, and estuaries. The reviews in this collection focus on the types of waters whose protections under the U.S. Clean Water Act have been called into question by U.S. Supreme Court cases. We synthesize 40+ years of research on longitudinal, lateral, and vertical fluxes of energy, material, and biota between aquatic ecosystems included within the Act's frame of reference. Many questions about the roles of streams and wetlands in sustaining downstream water integrity can be answered from currently available literature, and emerging research is rapidly closing data gaps with exciting new insights into aquatic connectivity and function at local, watershed, and regional scales. Synthesis of foundational and emerging research is needed to support science‐based efforts to provide safe, reliable sources of fresh water for present and future generations.     

Physiological responses of the calcifying rhodophyte, <Emphasis Type="Italic">Corallina officinalis</Emphasis> (L.), to future CO<Subscript>2</Subscript> levels

Future atmospheric CO₂ levels will most likely have complex consequences for marine organisms, particulary photosynthetic calcifying organisms. Corallina officinalis L. is an erect calcifying macroalga found in the inter- and subtidal regions of temperate rocky coastlines and provides important substrate and refugia for marine meiofauna. The main goal of the current study was to determine the physiological responses of C. officinalis to increased CO₂ concentrations expected to occur within the next century and beyond. Our results show that growth and production of inorganic material decreased under high CO₂ levels, while carbonic anhydrase activity was stimulated and negatively correlated to algal inorganic content. Photosynthetic efficiency based on oxygen evolution was also negatively affected by increased CO₂. The results of this study indicate that C. officinalis may become less competitive under future CO₂ levels, which could result in structural changes in future temperate intertidal communities.     

Pleistocene diversification of the Pomacentrus coelestis species complex (Pisces: Pomacentridae): historical biogeography and species boundaries

Pleistocene eustatic changes in sea level are often invoked to explain genetic divergence among marine organisms. However, molecular phylogenies have revealed relatively few examples of speciation events dating to the Pleistocene. We present a species-level hypothesis of the timing of evolution for the Pomacentrus coelestis species complex (Pomacentridae), based on the nuclear S7 intron and the mitochondrial Cytb gene, and reconstruct ancestral range distributions across the timetree. Ancestral range reconstruction suggests the complex originated in the Coral Triangle and East Indian Ocean, with subsequent range expansion outward from this region. We suggest that land barriers to dispersal (e.g., Indo-Pacific barrier) may be responsible for the divergence between Indian (P. alleni, P. similis, P. caeruleopunctatus, and P. caeruleus) and Pacific (P. micronesicus, P. auriventris, and P. coelestis) species groups, and subsequent isolation by Pleistocene sea-level fluctuations in certain areas of the Coral Triangle (glacial refugia) may play an important role in the diversification of this species complex. Additionally, our analyses show cryptic lineages within P. micronesicus and highlight the need for comprehensive sampling within and among species to reveal recent speciation events.     

Pathways for the oxidation of sarin in urban atmospheres

The nerve agent sarin has recently been deployed by terrorists in a major city. The molecule is volatile and made its way to many victims by passing as vapor through a highly reactive medium. Here we estimate rates and pathways for the removal of gas phase sarin from a generalized urban atmosphere. Only information from the open scientific literature is used. By structure reactivity comparisons with the organophosphorus pesticides, hydroxyl radical hydrogen abstraction may occur in as little as one hour. Decomposition of side chains after hydroxyl attack leads to organic oxygenates which preserve the phosphonofluoridate and so toxicity. The aqueous aerosol surface is contacted in minutes and offers access to a range of dissolved nucleophiles. Substitution displaces the fluoride leaving group, giving safe phosphoric acid analogs. Because of uncertainties in the electron distribution and in aqueous decay mechanisms, the time constants must be viewed as lower limits.     

Surveys of historic parks and gardens

The United Kingdom offers some of the finest designed parks and garden landscapes in the world and, whilst there is a wide range of skills and a wealth of literature on the subject, there is little evidence of official effort to systematically record historic sites. This, it is argued, is a factor in the continuing decline of many examples. This paper records an attempt at a comprehensive examination of one county — Cheshire — begun in 1970. The method is described and the results discussed in some detail. Some suggestions are put forward for improvements to official incentives for site owners.     

Interaction between water flow and spatial distribution of microbial growth in a two-dimensional flow field in saturated porous media

Bacterial growth and its interaction with water flow was investigated in a two-dimensional flow field in a saturated porous medium. A flow cell (56 x 44 x 1 cm) was filled with glass beads and operated under a continuous flow of a mineral medium containing nitrate as electron acceptor. A glucose solution was injected through an injection port, simulating a point source contamination. Visible light transmission was used to observe the distribution of the growing biomass and water flow during the experiment. At the end of the experiment (on day 31), porous medium samples were destructively collected and analyzed for abundance of total and active bacterial cells, bacterial cell volume and concentration of polysaccharides and proteins. Microbial growth was observed in two stripes along the length of the flow cell, starting at the glucose injection port, where highest biomass concentrations were obtained. The spatial distribution of biomass indicated that microbial activity was limited by transverse mixing between glucose and nitrate media, as only in the mixing zone between the media high biological activities were achieved. The ability of the biomass to change the flow pattern in the flow cell was observed, indicating that the biomass was locally reducing the hydraulic conductivity of the porous medium. This bioclogging effect became evident when the injection of the glucose solution was turned off and water flow still bypassed the area around the glucose injection port, preserving the flow pattern as it was during the injection of the glucose solution. As flow bypass was possible in this system, the average hydraulic properties of the flow cell were not affected by the produced biomass. Even in the vicinity of the injection port, the total volume of the bacterial cells remained below 0.01% of the pore space and was unlikely to be responsible for the bioclogging. However, the bacteria produced large amounts of extracellular polymeric substances (EPS), which likely caused the observed bioclogging effects.     

整全,互动和可持续的EIA：香港上水屠宰场的例案研究

以香港上水屠宰场的ＥＩＡ为例，阐述了ＥＩＡ过程须结合“清洁工艺”、“环境管理系统”、“持续生的本底监测”和“开放的公众咨询”四个重要单元，互动灵活，以增强环保效益、省时及经济。传统的ＥＩＡ较为被动，如果项目“倡议人”缺乏环保意识，就会妨碍了它的实质功能。通行的末期性公众咨询，很容易激发冲突，与西方冗长的公众参与同样妨碍进度。文章探讨互动式ＥＩＡ的优点，论证它对改善环评工序和可持续发展的重要性。