Determination of highly carcinogenic dibenzopyrene isomers in particulate emissions from two diesel- and two gasoline-fuelled light-duty vehicles

Emission factors of particulate-bound Polycyclic Aromatic Hydrocarbons (PAHs) including benzo(a)pyrene and, for the first time, the highly carcinogenic dibenzo(a,l)pyrene, dibenzo(a,e)pyrene, dibenzo(a,i)pyrene and dibenzo(a,h)pyrene have been determined in exhausts from two diesel- (DFVs) and two gasoline-fuelled light-duty vehicles (GFVs) operated in the Urban (AU), Rural Road (AR) and Motorway (AM) transient ARTEMIS driving cycles. The obtained results showed the DFVs to emit higher amounts of PAHs than the GFVs per km driving distance at low average speed in the AU driving cycle, while the GFVs emitted higher amounts of PAHs than the DFVs per km driving distance at higher average speeds in the AR and AM driving cycles. Furthermore, the study showed an increase in PAH emissions per km driving distance with increasing average speed for the GFVs with the opposite trend found for the DFVs. The GFVs generated particulate matter with higher PAH content than the DFVs in all three driving cycles tested with the highest concentrations obtained in the AR driving cycle. Dibenzo(a,l)pyrene was found to be a major contributor to the potential carcinogenicity accounting for 58–67% and 25–31% of the sum added potential carcinogenicity of the measured PAHs in the emitted particulate matter from the DFVs and GFVs, respectively. Corresponding values for benzo(a)pyrene were 16–25% and 11–40% for the DFVs and GFVs, respectively. The DFVs displayed higher sum added potential carcinogenicity of the measured PAHs than the GFVs in the AU driving cycle with the opposite trend found in the AR and AM driving cycles. The findings of this study show the importance of including the dibenzopyrenes in vehicle exhaust chemical characterizations to avoid potential underestimation of the carcinogenic activity of the emissions. The lower emissions and the lower sum added potential carcinogenicity of the measured PAHs found in this study for the GFVs compared to the DFVs in the AU driving cycle indicate the GFVs to be preferred in dense urban areas with traffic moving at low average speeds with multiple start and stops. However, the obtained results suggest the opposite to be true at higher average speeds with driving at rural roads and motorways. Further studies are, however, needed to establish if the observed differences between GFVs and DFVs are generally valid as well as to study the effects on variations in vehicle/engine type, ambient temperature, fuel and driving conditions on the emission factors.     

"It's not that simple": A collaborative comparison of sea ice environments, their uses, observed changes, and adaptations in Barrow, Alaska, USA, and Clyde River, Nunavut, Canada

The Arctic environment, including sea ice, is changing. The impacts of these changes to Inuit and I?upiat ways of life vary from place to place, yet there are common themes as well. The study reported here involved an exchange of hunters, Elders, and others from Barrow, Alaska, USA, and Clyde River, Nunavut, Canada, as members of a larger research team that also included visiting scientists. Although the physical environments of Barrow and Clyde River are strikingly different, the uses of the marine environment by residents, including sea ice, had many common elements. In both locations, too, extensive changes have been observed in recent years, forcing local residents to respond in a variety of ways. Although generally in agreement or complementary to one another, scientific and indigenous knowledge of sea ice often reflect different perspectives and emphases. Making generalizations about impacts and responses is challenging and should therefore be approached with caution. Technology provides some potential assistance in adapting to changing sea ice, but by itself, it is insufficient and can sometimes have undesirable consequences. Reliable knowledge that can be applied under changing conditions is essential. Collaborative research and firsthand experience are critical to generating such new knowledge.     

Short- and long-term outcomes of gestational diabetes and its treatment on fetal development

Globally the prevalence of gestational diabetes mellitus (GDM) is rising mainly due to the increase in maternal obesity. A number of different methods to screen for and diagnose GDM have been described although consensus on the preferred methods does not yet exist. GDM has significant short- and long-term health risks for the mother, developing fetus and the children born to mothers with GDM. Short-term risks for the fetus include macrosomia (excessive birthweight), shoulder dystocia, birth trauma, and hypoglycaemia in the immediate postpartum period. Long-term risks for offspring born to mothers with GDM include increased rates of childhood and adulthood obesity and an increased cardiometabolic risk. A number of pharmacological treatments for GDM have been identified, these include insulin and oral glucose-lowering drugs metformin and glibenclamide. Whilst these oral glucose-lowering drugs show similar short-term childhood outcomes to insulin there is increasing evidence that these drugs may have adverse long-term outcomes on children and adults exposed to the drugs in utero. Future research on treatments for GDM should include long-term follow- up of children exposed to glucose lowering medication in utero to determine the long-term cardiometabolic risk in the offspring born to mothers with GDM.     

The first definitive carcharodontosaurid (Dinosauria: Theropoda) from Asia and the delayed ascent of tyrannosaurids

Little is known about the evolution of large-bodied theropod dinosaurs during the Early to mid Cretaceous in Asia. Prior to this time, Asia was home to an endemic fauna of basal tetanurans, whereas terminal Cretaceous ecosystems were dominated by tyrannosaurids, but the intervening 60 million years left a sparse fossil record. Here, we redescribe the enigmatic large-bodied Chilantaisaurus maortuensis from the Turonian of Inner Mongolia, China. We refer this species to a new genus, Shaochilong, and analyze its systematic affinities. Although Shaochilong has previously been allied with several disparate theropod groups (Megalosauridae, Allosauridae, Tyrannosauroidea, Maniraptora), we find strong support for a derived carcharodontosaurid placement. As such, Shaochilong is the first unequivocal Asian member of Carcharodontosauridae, which was once thought to be restricted to Gondwana. The discovery of an Asian carcharodontosaurid indicates that this clade was cosmopolitan in the Early to mid Cretaceous and that Asian large-bodied theropod faunas were no longer endemic at this time. It may also suggest that the ascent of tyrannosaurids into the large-bodied dinosaurian predator niche was a late event that occurred towards the end of the Cretaceous, between the Turonian and the Campanian. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

NUTRIENT BALANCES FOR THE EVALUATION OF NUTRIENT SOURCES IN WATER QUALITY MANAGEMENT1

ABSTRACT. This paper describes the methodology for a nutrient balance to evaluate the sources and distribution of nutrients in a small river basin. Loadings for total nitrogen and phosphorus are calculated from measured nutrient concentration and river discharge data. Using a special retrieval program and a data storage and processing system, loadings are accumulated over a given time period to allow for time of passage through the basin and seasonal changes in nutrient distribution. Nutrient balances are made with the accumulated loadings to obtain the relative contribution of each nutrient source and the retention of nutrients within the basin through sedimentation and aquatic growth. The methodology has been used to study nutrients in the Qu'Appelle River Basin, Saskatchewan, Canada.     

PRIMARY AND SECONDARY IMPACTS OF A WATER RESOURCE DEVELOPMENT PROJECT1

ABSTRACT: At a time in history when water resource development in the United States is being condemned as both economically inefficient and an environmental disaster, perhaps economists need to look back at previous development to see what the fruits of water development (be they sweet or sour) have been. The Boise Project of south-western Idaho is 70 years old and to some people it represents a gross error in resource use, while to others it represents a means of livelihood and well being. A recent research project at the University of Idaho attempted to measure not only the direct economic income benefits of the project (from irrigation), but also the indirect or secondary income benefits (from the food processing industry). Periodic regional input-output tables were constructed to assess the income generated from irrigation and food processing over the period from 1946 to 1970. Input-output analysis allowed researchers to evaluate the direct and indirect impacts of both the irrigation sector and the food processing sector and to compare their growth over time.     

HIERARCHICAL DIVERSITY OF COMMUNITIES OF AQUATIC INSECTS AND FISHES1

ABSTRACT: Hierarchical diversity analysis of data on fish and aquatic insects showed that the component of diversity contributed by the species level was generally very small compared with the component at the generic level or with the total diversity. Very high rank correlations between generic diversity, in which genera were discriminated but not identified, and species diversity suggested that the purposes of environmental monitoring might best be served by working at the generic level rather than the species level. This is particularly true when an index of diversity is to be used as the major comparative and communicative tool. The savings of time and money could be appreciable.     

Reviews

REGIONAL PLANNING: A COMPREHENSIVE VIEW

JEREMY ALDEN and ROBERT MORGAN

Leonard Hill Books, Intertext, London, 1974. £6.

MAN‐MADE FUTURES: READINGS IN SOCIETY, TECHNOLOGY AND DESIGN

NIGEL CROSS, DAVID ELLIOTT and ROBIN ROY (EDS.)

Hutchinson Educational in association with Open University Press, London, 1974. 365 pp., cased £5, paperback £2.75.

CITY OF BIRMINGHAM STRUCTURE PLAN: WRITTEN STATEMENT

NEVILLE BORG (City Engineer)

City of Birmingham, 1973.

DESIGNING FOR HUMAN BEHAVIOUR: ARCHITECTURE AND THE BEHAVIOURAL SCIENCES

(Community Development Series. Series Editor, Richard P. Dober.)

JON LANG, CHARLES BURNETTE, WALTER MOLESKI and DAVID VACHON (EDS.)

Dowden, Hutchinson & Ross, Inc., Stroudsburg, Pa., 1974. 352 pp., S20 (U.K. price not stated).

THE BOOK OF GARDEN ORNAMENT

PETER HUNT (ED.)

J. M. Dent & Co., London, 1974. £9.75.

AMENITY AND URBAN PLANNING

DAVID L. SMITH

Crosby Lockwood Staples, London, 1974. 198 pp. £4.50.