bluuebunny/crossref_metadata_2025 huggingface dataset:
Road-traffic deaths in China, 1985–2005: threat and opportunity
Authors: Hu G , Wen M , Baker T D , Baker S P
Published: June 2008

Objective:

To examine recent trends and geographic variations in road-traffic deaths in China.

Design:

A longitudinal descriptive analysis of national and provincial data on road-traffic deaths, examining recent trends and geographic variations.

Setting:

China, 1985–2005.

Data sources:

TheTransportation and communications yearbook of China(1986–2006) and theNational statistics yearbook of China(1996–2006).

Main outcome measures:

The percentage change in death rates per 100 000 population was used to examine the trend. Epi Info was used to map the geographic distribution of road-traffic death rates and the increases in rates. Correlation coefficients were calculated between per capita gross regional product, road quality, and the number of motor vehicles in the 31 provinces, to help understand the geographic variations in road-traffic mortality at the provincial level in China.

Results:

The road-traffic death rate increased by 95%, from 3.9/100 000 persons in 1985 to 7.6/100 000 persons in 2005. High death rates and the greatest increases in death rates occurred in both developed provinces in the southeast and underdeveloped northern and western provinces. Xizang/Tibet, Qinghai, and Xinjiang, with the lowest population density, had the highest death rates per 100 vehicles.

Conclusions:

China’s government should introduce and support measures to prevent road-traffic injuries. Developed and underdeveloped provinces in China should both be considered when road-traffic policy and interventions are developed.
Vehicle rollover risk and electronic stability control systems
Authors: MacLennan P A , Marshall T , Griffin R , Purcell M , McGwin G , Rue L W
Published: June 2008

Background:

Electronic stability control (ESC) systems were developed to reduce motor vehicle collisions (MVCs) caused by loss of control. Introduced in Europe in 1995 and in the USA in 1996, ESC is designed to improve vehicle lateral stability by electronically detecting and automatically assisting drivers in unfavorable situations.

Aim:

To examine the relationship between vehicle rollover risk and presence of ESC using a large national database of MVCs.

Methods:

A retrospective cohort study for the period 1995 through 2006 was carried out using data obtained from the National Automotive Sampling System General Estimates System. All passenger cars and sport utility vehicles (SUVs)/vans of model year 1996 and later were eligible. Vehicle ESC (unavailable, optional, standard) was determined on the basis of make, model, and model year. Risk ratios (RRs) and 95% CIs were calculated to compare rollover risk by vehicle ESC group.

Results:

For all crashes, vehicles equipped with standard ESC had decreased risk of rollover (RR = 0.62, 95% CI 0.50 to 0.77) compared with vehicles with ESC unavailable. The association was consistent for single-vehicle MVCs (RR = 0.61, 95% CI 0.46 to 0.82); passenger cars had decreased rollover risk (RR = 0.77, 95% CI 0.52 to 1.12), but SUVs/vans had a more dramatically decreased risk (RR = 0.40, 95% CI 0.26 to 0.61).

Conclusions:

This study supports previous results showing ESC to be effective in reducing the risk of rollover. ESC is more effective in SUVs/vans for rollovers related to single-vehicle MVCs.
School-age children’s safety attitudes, cognitions, knowledge, and injury experiences: how do these relate to their safety practices?
Authors: Morrongiello B A , Cusimano M , Orr E , Barton B , Chipman M , Tyberg J , Kulkarini A , Khanlou N , Masi R , Bekele T
Published: June 2008

Background:

A variety of factors affect the safety and risk practices of school-age children, but rarely have multiple factors been considered simultaneously.

Objective:

To examine children’s safety attitudes and cognitions more thoroughly and assess how these factors, along with children’s safety knowledge and injury experiences, relate to children’s safety practices.

Methods:

Over several classroom sessions, boys and girls in two age groups (7–9, 10–12 years) completed a psychometrically sound questionnaire that indexes their behaviors, attitudes, cognitions, knowledge, and injury experiences.

Results:

Fewer safety practices were reported by older than younger children and boys than girls. Children’s attitudes, cognitions, knowledge, and injury experiences each correlated with safety practices, but only safety attitudes and injury experiences predicted practices in a multivariate model.

Conclusion:

Exploring the relative influence of numerous factors on safety practices highlights the important role that attitudes play in predicting children’s safety practices. Implications of these results for injury prevention programming are discussed.
Do inadequacies in ICD-10-AM activity coded data lead to underestimates of the population frequency of sports/leisure injuries?
Authors: Finch C F , Boufous S
Published: June 2008

Aims:

To assess the use of the International Classification of Diseases Australian Modification (ICD-10-AM) activity sub-codes for identifying sports/leisure injury hospitalizations and the impact of missing codes on population incidence estimates.

Methods:

Injury-related hospital separations in New South Wales, Australia, for the period 2003–04 were examined with sports/leisure cases identified by the ICD-10-AM activity codes.

Results:

Over 30% of all injury hospitalizations had either a missing or unspecified activity code. Among cases with valid activity codes, 13.9% of all injury hospitalizations were associated with sports/leisure. When adjusted for underreporting associated with undefined or missing activity codes, sports/leisure injuries accounted for up to 20% of injury hospitalizations.

Conclusion:

Defining sports/leisure injury cases on the basis of activity codes is likely to lead to an underestimate of their contribution to the overall injury burden. Improvements need to be made to the completeness of activity coding of hospitalization data.
Validating parents’ self-reports of children’s exposure to potentially toxic substances within the home
Authors: Patel B , Devalia B , Kendrick D , Groom L
Published: June 2008

Objective:

To validate self-reported possession and storage of a range of substances within the home.

Participants:

30 families with children aged 12–35 months on health visitor caseloads in Nottingham, UK.

Methods:

Self-reported possession and storage of potentially hazardous substances were validated by observations. Sensitivity, specificity, and predictive values were calculated for possession, storage, and exposure to substances.

Results:

Self-reported low exposure to substances had high sensitivities (87–100%) and positive predictive values (75–100%) for all substances, except toilet cleaner (positive predictive value 62%) and high negative predictive values for commonly owned household products. Specificity and negative predictive value could not be estimated reliably for medicines and less commonly owned household products, as few families stored these unsafely.

Conclusions:

A measurement of exposure that combines self-reported possession and storage may be sufficiently accurate to identify families with safer poison prevention practices.
Effects of financing smoking cessation outpatient services in Taiwan
Authors: Chang F-C , Hu T-W , Lin M , Yu P-T , Chao K-Y
Published: June 2008

Objective:

This study assesses the effects of a 2005 increase in funding for smoking cessation services on provider participation, patient utilisation of smoking cessation services and cessation outcome at a six-month follow-up.

Methods:

Analyses are based on existing databases and on a follow-up study among smokers participating in the smoking cessation service. The effect of the policy is evaluated by comparing year 2004 (old policy) with year 2005 (new policy). The generalised estimating equations (GEE) method was conducted to examine the effects of increasing funding for smoking cessation services on monthly smoking cessation services provided per physician and yearly consultations received per patient. Logistic regression was used to examine the effects of increasing funding on smoking cessation outcome.

Results:

The study found the increased reimbursement rates and medication subsidies for smoking cessation to be positively related to the number of physicians enrolling in the programme (1841 in 2004 vs 3466 in 2005), the number of cessation consultations per month per physician (5.1 vs 14.6) and the number of cessation visits per year per patient (2.0 vs 2.5). Male providers and providers belonging to the private sector were found to offer more cessation consultations. The number of subjects receiving this counselling increased from 22 167 in 2004 to 109 508 in 2005. After adjusting for consumer and provider factors the likelihood of successful quitting among those counselled did not change. Overall, smokers who were older, had attempted to quit in the past year, had lower nicotine dependence, had gone to more smoking cessation service visits, had received consultations in the public sector and were seen by physicians delivering fewer consultations were more likely to have quit smoking at the six-month follow-up.

Conclusions:

Based on increases in physician enrolment and consultations and the increase in number of subjects receiving counselling and number of visits, the policy of increasing provider incentives and medication subsidies appears to have successfully promoted smoking cessation services.
A cluster-randomised controlled trial of a brief training session to facilitate general practitioner referral to smoking cessation treatment
Authors: McRobbie H , Hajek P , Feder G , Eldridge S
Published: June 2008

Objectives:

General practitioners (GPs) are the main source of referrals to specialist smoking cessation services (SSCS), but the referral rates are low. We evaluated effects of a brief GP training session on the number of referrals received by their local SSCS.

Methods:

A cluster-randomised controlled trial was undertaken across three East London primary care trusts. A total of 91 GPs were randomly allocated to a training session or usual care. Participants in the intervention arm were offered a 40-min training session addressing the rationale and skills for referral of smokers for treatment. Participants in the usual care arm received referral guidance by post. The main outcome measure was the number of referrals recorded by the SSCS over 3 months after the intervention.

Results:

Over the 3-month baseline period the average number of referrals per GP was 1.0 and 0.6 in the intervention and usual care arms, respectively. During the post-intervention period the mean number of referrals was 6.4 and 1.8 per GP. When adjusting for baseline variables the incidence rate ratio for the referrals from the intervention arm compared to usual care was 4.9 (p<0.001; 95 CI 1.7 to 14.7).

Conclusion:

A brief training session can significantly increase GP referral to smoking cessation services.

Trial registration:

National Research Register, Department of Health, UK N0261148824 (available online at:http://www.nrr.nhs.uk/ViewDocument.asp?ID  N0261148824)
CYTOSPORA CANKER OF POPLARS: FACTORS INFLUENCING THE DEVELOPMENT OF THE DISEASE
Authors: Bloomberg W. J.
Published: June 2008

The effects of shoot moisture content, region of shoot, age of shoot, temperature, relative humidity, and soil moisture content on the development of cankers caused by Cytospora chrysosperma (Pers.) Fr. were studied in Populus trichocarpa Torr. and Gray, P. × canadensis Moench 'Regenerata', and P. × canadensis 'Robusta Bachelieri'. Within the range studied, canker growth varied proportionally with temperature, and inversely with shoot moisture content, relative humidity, and soil moisture content. Canker growth was greater in P. trichocarpa than in the two hybrids, which did not differ significantly from each other. Canker growth was less in 8-month-old than in 10- and 12-month-old shoots of the hybrids, but cankers on P. trichocarpa showed no differences in this respect. The critical bark moisture deficit for infection was least in P. trichocarpa, intermediate in P. 'Regenerata', and greatest in P. 'Robusta'. The critical bark moisture deficit was greater, and the incubation period was shorter, in the upper part than in the lower part of the shoot.
CYTOSPORA CANKER OF POPLARS: THE MOISTURE RELATIONS AND ANATOMY OF THE HOST
Authors: Bloomberg W. J.
Published: June 2008

A comparison was made between Populus trichocarpa Torr. and Gray, P. × canadensis Moench 'Regenerata', and P. × canadensis 'Robusta Bachelieri' with respect to shoot moisture relations and anatomy. The two hybrid varieties had slower rates of moisture loss and had higher wood moisture contents throughout most of the year than P. trichocarpa. The bark and wood moisture content of the three varieties was lower during dormancy than in the growing season. The upper region of the shoots had lower bark and wood moisture contents than the basal region during dormancy, but the reverse was true in summer. In all varieties, there was a significant positive correlation between wood and bark moisture content. Compared with P. trichocarpa, the two hybrids had larger piths, wider vessels, longer phloem rays, wider sieve tube zones, and thicker periderms; P. 'Robusta' had fewer lenticels. The upper region of the shoots had a wider pith, thicker bark, thinner periderm, and more lenticels than the basal region. The differences in moisture relations and anatomy of the three varieties suggest an explanation for the observed greater resistance to canker disease caused by Cytospora chrysosperma (Pers.) Fr. in the hybrids than in P. trichocarpa.
LEAF GROWTH IN MARQUIS WHEAT, AS REGULATED BY TEMPERATURE, LIGHT INTENSITY, AND DAYLENGTH
Authors: Friend D. J. C. , Helson V. A. , Fisher J. E.
Published: June 2008

The area of a fully-grown leaf lamina varied according to its position on the stem, and the temperature, light intensity, and photoperiod under which the plant was grown.In continuous illumination, raising the temperature by 5° intervals between 10 and 25 °C, resulted in progressively higher rates of leaf initiation, emergence, and expansion. The length of the lamina increased with each increase in temperature, but the breadth and thickness decreased. The greatest area of individual leaves was formed at 20 °C. Each increase in light intensity over the range 200, 500, 1000, 1750, and 2500 ft-c resulted in higher rates of leaf initiation, emergence, and expansion, and increases in breadth and thickness, but a decrease in length. The greatest area was formed at 1000–1750 ft-c.An increase in daylength from 8 to 24 hours increased leaf length, breadth, and area. This was a photoperiodic effect, unlike the increase in thickness with increased daylength, which was related to the total light energy received.Changes in leaf shape under different environmental conditions were not directly related to changes in leaf dry weight. A control of leaf growth by hormonal mechanisms sensitive to photoperiod seems more probable than does control by internal competition for assimilates among developing leaves.
WETWOOD FORMATION IN BALSAM FIR
Authors: Etheridge D. E. , Morin L. A.
Published: June 2008

The occurrence and distribution of wetwood in balsam fir (Abies balsamea (L.) Mill. was investigated from the standpoint of determining the factors affecting its formation. Young, rapidly growing trees, namely those with wide annual rings, were found to be most subject to wetwood. This has been attributed to an incomplete branch healing, which promotes the direct entry of rainwater to the stem. Branch healing associated with narrow annual rings was such that it prevented water penetration. Wetwood in balsam fir was concentrated in the mid-stem region, becoming progressively less prevalent in the branchless lower bole and towards the living crown. The internal distribution of wetwood is explained by the prevalence of branch stubs in the region of the mid-stem and the capacity of such branches to trap and conduct water to the interior.
STUDIES ON ASCOCHYTA IMPERFECTA PECK.: CHANGES IN PHYSICAL CHARACTERISTICS OF CANADIAN ISOLATES ON AGAR AMENDED WITH VARIOUS AMINO ACIDS
Authors: Mead H. W.
Published: June 2008

Twenty isolates of Ascochyta imperfecta were grown on a basic agar amended singly with 12 amino acids. The isolates changed differentially in color, marginal outline, aerial mycelium, and extent of radial growth. It is suggested that these responses are significant in the light of known differences in content of various amino acids in tissues of alfalfa, and changes which occur in this content under the influence of environment and artificial soil amendments.
Morphology of edible plant cells and tissues in vitro
Authors: Kant U. , Hildebrandt A. C.
Published: June 2008

Morphological features were studied of callus tissues from carrot root, endive embryo, lettuce leaf petiole and stem, parsley and spinach leaf petiole, and navy bean and red kidney bean stem grown on solid C- or D-medium. The callus tissue of carrot, endive, lettuce leaf petiole and stem, parsley, and red kidney bean were irregularly lobed while the callus tissues of navy bean and spinach were hemispherical and somewhat flattened, respectively. The cultures of carrot and endive were firm and massive, while the calli of other species were friable. Callus cells of these seven species, examined with the phase microscope, varied in size and shape. The callus cells of carrot, lettuce leaf petiole and stem, navy bean, and red kidney bean were spherical, oval, and elongated. Endive callus tissue consisted of oval and elongated cells and that of parsley consisted of spherical and oval cells, while spinach callus usually consisted of spherical cells. Elongated cells ranged from 204 to 475 μ in length by 45 to 92 μ in width, spherical cells 62.5 to 129.8 μ in diameter, and oval cells 118 to 172.8 μ in length by 63 to 94.5 μ in width. Variations were noted in the morphology and number of cell inclusions including the nucleoli, plastids, mitochondria, and starch granules. In chlorophyllous cells, the chloroplasts were generally scattered in the cytoplasm, but in spinach it often surrounded and obscured the nucleus. Varying numbers of starch granules were seen around the nucleus and in the cytoplasm.
Cytology of ascus development in the genus Chaetomidium
Authors: Rao V. Ranga , Mukerji K. G.
Published: June 2008

The cytology of the ascus initiation and the ascus development in two species of the genus Chaetomidium Fuckel are described. In C. subfimeti, the initial of the ascus is the binucleate penultimate cell of the crozier, whereas in C. barbatum, in the absence of croziers, the ascus initial is a binucleate ascogenous cell. The sequential stages of ascus development (one-, two-, four-, and eight-nucleate asci) in the two species are reported. Mature ascospores are binucleate.
Effects of mercaptoethanol on tumor induction in a Nicotiana amphiploid
Authors: Ames I. H. , Smith H. H.
Published: June 2008

Young seedlings of the amphiploid Nicotiana glauca × N. langsdorffii, grown aseptically on nutrient medium, were treated with solutions containing 2-mercaptoethanol, and the incidence of tumor formation was scored for 30 days subsequent to exposure. Mercaptoethanol caused a marked acceleration in the rate of tumorigenesis when the pH of the test solution was in the alkaline range. The effectiveness of the compound was reduced by lowering the pH of the treatment solution.
Microfungi of crowns and roots of apparently healthy dormant strawberry plants
Authors: Gourley C. O.
Published: June 2008

The crowns and roots of 100 cold-stored, apparently healthy strawberry plants of each of the varieties Acadia, Catskill, Cavalier, Gorella, Guardsman, Midway, Redcoat, Sparkle, and Surecrop were examined for their fungal content. Crowns contained representatives of 43 genera; roots contained 38, of which 36 were in both crowns and roots. Strawberry foliar and fruit pathogens were present in a relatively small number of the crowns and roots. In general, Chaetomium spp. and Fusarium spp. were the most prevalent. Chaetomium cochliodes was more prevalent in Cavalier and Redcoat, the varieties most susceptible to root rot in the field, than in the other varieties. The crowns and roots of apparently healthy, dormant strawberry plants contained a fungal flora similar to that associated with the black root rot complex.One fungus, Varicosporium elodeae, isolated from strawberry plants has not previously been reported in Canada.
The production of a host-specific pathotoxin by Cochliobolus heterostrophus
Authors: Smedegard-Petersen V. , Nelson R. R.
Published: June 2008

Certain isolates of Cochliobolus heterostrophus which induce blight reactions on corn produce a host-specific pathotoxin. Blighting symptoms are characterized initially by a diffuse, generalized watersoaking and chlorosis of leaf tissue apparent 2 to 3 days after inoculation, then rapid necrosis of the affected tissue. Filtrates were obtained from cultures grown on Fries' modified medium with 2% yeast extract. Toxin production was measured by dilution end point methods using a seedling bioassay measuring inhibition of root elongation and detached leaves floated on culture filtrates. Minimum pH of filtrates was correlated with maximum mycelial growth and occurred 9–11 days after inoculation. Maximum toxin production occurred 4–6 days later. Culture filtrates and extracts from diseased plants induced all disease symptoms and exhibited the same specificity as the pathogen to susceptible and resistant lines of corn. Sorghum vulgare and Sorghum Sudanese were susceptible to the isolates and their toxin, while eight other gramineous species were resistant to both sources of inocula. Toxin production was shown to be under genetic control in that ascospore progeny with greater or lesser toxin capacities than parental isolates were obtained from genetic crosses. Certain of the chemical characteristics of the pathotoxin were determined.
Assorted angiosperm pollen from the Edmonton Formation (Maestrichtian), Alberta, Canada
Authors: Srivastava Satish K.
Published: June 2008

Thirty-three species of angiosperm pollen belonging to 20 form genera are described from the Edmonton Formation (Maestrichtian) of Alberta. Three genera, viz. Nothopollenites, Gunnaripollis, and Marcellopollenites, are formally designated here. Twenty-four species are newly described. The stratigraphic occurrence of individual taxa within the Edmonton Formation is indicated.
Formation of heartwood phenols in callus tissue cultures of red pine (Pinus resinosa)
Authors: Jorgensen E. , Balsillie D.
Published: June 2008

Pinosylvin (3,5-dihydroxy-stilbene) and Pinosylvin monomethyl ether (3-hydroxy-5-methoxy-stilbene) were formed by cells in callus tissue cultures of Pinus resinosa Ait., when these cells were subjected to desiccation leading to death over a period of time at 25 °C. Pinosylvin and Pinosylvin monomethyl ether were absent in check cultures growing under normal conditions at the same temperature.The significance of the above findings is discussed in relation to the theory of "protection wood formation" in trees as well as for biochemical studies on the biosynthesis of heartwood phenols in trees.
Response of soybean leaf water relations to tropospheric ozone
Authors: Fiscus Edwin L. , Miller Joseph E. , Booker Fitzgerald L. , Reid Chantal D.
Published: June 2008

Tropospheric O3 and water stress cause significant reductions in crop growth and yield. The effects of chronic O3 exposures on leaf water relations have been less thoroughly studied. Soybeans were grown in two years in open-top field chambers equipped to control O3. The seasonal mean O3 concentrations for the charcoal-filtered controls and supplemental O3 treatments were 24 and 83 nL∙L−1 for the first year (1990) and 20 and 99 nL∙L−1 for the second year (1992). In 1990 leaves were sampled during four intervals of the 106-d growing season and subjected to potential–volume analysis. In 1992, leaves were sampled over a 3-week period, centered on 49 days after planting for potential–volume analysis as well as for midday xylem pressure potentials and leaf conductance. Ontogenetic changes in most of the parameters were large compared with treatment effects. O3 treatment consistently caused decreased symplastic volume, specific leaf mass, and tissue elasticity. In 1992, these effects were accompanied by decreased leaf conductances with no discernable change in xylem pressure potential, although midday turgor increased by 32% and stomatal competency was maintained. Tissue elasticity decreases may be related to O3-induced changes in cell wall structure during leaf expansion and may result in decreased symplastic volume. Key words: Glycine max, ozone, leaf water relations, pressure–volume analysis, elasticity, elastic modulus.
Analyse macrofossile d'une palse subarctique (Québec nordique)
Authors: Lavoie Claude , Payette Serge
Published: June 2008

Plant and animal macrofossils (vascular plant, moss, fungus, bryozoan, cladoceran and coleoptera remains) were analyzed to reconstitute the development of a palsa peat located at the northwestern forest limit of subarctic Quebec (57°45′N., 76°15′W.) and to detect any black spruce (Picea mariana) remains older than the presumed time of arrival of the species in the study area (4560 BP), after the deglaciation. The oldest peat deposits were formed in a fen with many shallow pools between 5850 and 4500 BP. The flora was mainly composed of aquatic taxa (Ranunculus trichophyllus, Potamogeton spp., Hippuris vulgaris). Around 4500 BP, there was a shift from a very wet fen to a sedge fen with Potentilla palustris and Menyanthes trifoliata. From 3700 to 1950 BP, most plant remains were wood fragments of dwarf birch (Betula glandulosa). The formation of the palsa occurred after 1950 BP. The development of this peatland is similar to that of other palsa peatlands of subarctic Quebec, except that it is characterized by the presence of a thick peat layer composed of Betula glandulosa fragments at the top of the palsa. There were no black spruce remains older than 4560 BP. Three peaks of coleoptera abundance were identified at 4400, 3800, and 2700 BP, respectively. Most of the coleoptera taxa being hygrophilous, it was not possible to infer structural changes in the peatland from their fragments. Key words: palsa peatland, macrofossil analysis, subarctic Quebec, Betula glandulosa, Picea mariana, beetles.
Freshwater hyphomycete communities in a canal. 1. Endophytic hyphomycetes of submerged roots of trees sheltering a canal bank
Authors: Iqbal S. H. , Bareen Firdaus-e- , Yousaf Noureen
Published: June 2008

Seventeen species of freshwater hyphomycetes were found as endophytes of roots of Mangifera indica, Populus hybrida, and Salix babylonica extending into the water from crevices in the brick wall of a canal in Lahore, Pakistan. More species were recovered by aerating than by plating bark and xylem segments on malt extract agar. Endophytic species of bark outnumbered those of xylem detected by aeration and plating methods. Anguillospora longissima, Articulospora proliferata, Bacillispora aquatica, Flagellospora curvula, Flagellospora fusarioides, Flagellospora penicillioides, Fusarium sp., and Tetracladium marchalianum were produced in abundance on aerated root segments. Fusarium sp. dominated other endophytic species of three tree species. Fifteen, 14, and 12 species were recovered from Salix babylonica, Mangifera indica, and Populus hybrida, respectively. Campylospora chaetocladia was confined on the bark and Heliscus lugdunensis on the bark as well as xylem segments of Salix babylonica. Clavariopsis azlanii and Tricellula aquatica were recovered from roots of Mangifera indica. Key words: endophytic freshwater hyphomycetes, submerged roots, canal water.
Pseudostilbella euphorbiae, a new sporodochial hyphomycete, isolated from Euphorbia resinifera
Authors: Muntañola-Cvetković M. , Gómez-Bolea A.
Published: June 2008

Pseudostilbella anam. gen.nov. and Pseudostilbella euphorbiae anam. sp.nov. are proposed to accommodate a fungus isolated from lesions on living stems of Euphorbia resinifera Berg. collected in Morocco. The conidioma is a sporodochium borne on a rudimentary, brownish to greyish-brown, diffuse, KOH− stroma that is an extreme development of prosenchyma. The sparingly branched conidiophores develop from underlying pseudoparenchymatous cells. Conidiogenous cells form palisades and produce filiform, straight, or sinuous conidia. The conidiogenous system is holoblastic. Orange, slimy conidial masses accumulate on the colony surface or at the apex of synnema-like aggregations according to the location of the sporodochia. Sporodochia are sessile when colonies are grown under intense light, whereas they form at the apex of white stalks under diffuse light. Cultures grown in continuous darkness produce mycelial, synnema-like aggregations but do not sporulate. Light is thus needed for sporulation. Key words: Hyphomycetes, Euphorbia, fungal taxonomy, photomorphogenesis, sporodochial fungi.
Alewife (Alosa pseudoharengus) Survival During the First Growth Season in Southeastern Lake Michigan
Authors: Mansfield Pamela J. , Jude David J.
Published: June 2008

Alewife (Alosa pseudoharengus) survival from newly hatched larvae to fall young-of-the-year (YOY) was calculated using data collected in southeastern Lake Michigan, June–November 1974–82. Alewife YOY density (number per 1000 m3) was estimated from trawl catches. Larval alewife densities, derived from plankton net samples at trawling stations and from power plant entrainment samples, were averaged each year for length intervals which represented yolk-sac and post-yolk-sac larvae. Survival (ratios of YOY to larval alewife densities) varied considerably among years, but mean survival over all years from yolk-sac larvae to YOY was 1% calculated from either field-larvae or entrained-larvae data. Mean survival from post-yolk-sac larvae to YOY was higher, 2.2–4.6%. Daily mortality rates were 12–27% for larvae through yolk absorption, decreasing to 2–5% for juveniles. Differences in survival among years may be due to timing of sampling, distribution of larvae and YOY, or actual survival differences, perhaps related to predator abundance.
Effect of Ambient Oxygen Concentration on Measurements of Sediment Oxygen Consumption
Authors: Campbell P. J. , Rigler F. H.
Published: June 2008

The disparity between hypolimnetic oxygen depletion in situ (HOD; independent of the ambient oxygen concentration), used to calculate sediment oxygen consumption (SOC) in one lake in southern Quebec, and measurements of SOC (dependent on the oxygen concentration) was minimal when experimental factors were controlled. Using gas-tight methods, SOC at 7–5 mg∙L−1 decreased by 75% when the oxygen concentration in respirometers fell to 3–1 mg∙L−1. With continuous mixing, the comparable decrease in SOC was 50%. Finally, the decrease was less than 30% and obvious only below 2 mg∙L−1 when the oxygen concentration was held constant in continuous flow respirometers. SOC results using the last procedure were within 10% of the mean SOC calculated indirectly from hypolimnetic oxygen budgets for the two previous years. Thus, mixing and a constant or slowly changing ambient oxygen concentration are required for realistic SOC measurements. In another experiment, oxygen uptake in water overlying the sediment accounted for a large and variable portion of the SOC, often more than 50%. Therefore, it may be impossible to separate the influence of the water and sediment on the HOD.
Effect of Competition Between Two Freshwater Fishes on Prey Consumption and Abundance
Authors: Hanson John Mark , Leggett William C.
Published: June 2008

The effect of inter- and intraspecific competition on the type and quantity of food consumed by fish, and on the abundance of macroinvertebrate prey, was examined by manipulating densities of yellow perch (Perca flavescens) and pumpkinseed (Lepomis gibbosus) stocked into littoral zone enclosures at levels approximating 0.5, 1.0, and 2.0 times the measured total fish biomass on the littoral zone. In intraspecific competition experiments, neither species showed a change in the type of prey eaten (principally macroinvertebrates). The amount of food eaten by yellow perch reared at high (26 g/m2) densities was significantly depressed relative to that of perch reared at low (6.5 g/m2) and natural (13 g/m2) densities. There were no significant differences in the amount of food eaten by pumpkinseed at the three fish densities. The gut fullness of pumpkinseed reared at high densities, however, was biased to a significant but unknown degree by the inclusion of a nonfood item, macrophyte fragments, in the estimates. No other fish consumed macrophytes. In interspecific competition experiments, the gut fullness of yellow perch and pumpkinseed reared together (combined density 13 g/m2) did not differ from that of fish reared alone at low or natural densities. The diet (principally macroinvertebrates) of the superior competitor, pumpkinseed, did not change relative to that of pumpkinseed reared alone. The inferior competitor, yellow perch, exhibited a significant change in diet. Microcrustaceans (an energetically inferior food) comprised 30–53% of the diet (by weight) of yellow perch reared with pumpkinseed compared with < 1% of the diet of perch reared alone. Total macroinvertebrate biomass and abundance were unaffected by differences in fish biomass in the enclosures.
Differential Use of the Campbell River Estuary, British Columbia by Wild and Hatchery-Reared Juvenile Chinook Salmon (Oncorhynchus tshawytscha)
Authors: Levings C. D. , McAllister C. D. , Chang B. D.
Published: June 2008

From March 1982 to December 1983, juvenile chinook salmon (Oncorhynchus tshawytscha) were sampled by beach-seine in the Campbell River estuary and adjacent waters of Discovery Passage in order to examine estuarine use by wild and hatchery stocks. Wild juvenile chinook entered the estuary as migrant fry and were present in the estuarine zone mainly in late April to June, in the transition zone in mid-May to July, and in the marine zone in July. Hatchery fish were released from early May to early July. Maximum catches of wild stocks were similar in the estuarine and transition zones, while the maximum catches of most hatchery stocks were higher in the transition zone. For both wild and hatchery chinook, catches in the marine zone were much lower than in the estuarine and transition zones. Wild fry resided in the estuary for 40–60 d, while most hatchery fish used the estuary for about one-half this period. Wild stocks showed a relatively constant rate of increase in mean size from May to September. Higher rates of increase in the mean size of hatchery fish were shown by groups with earlier release dates and smaller mean sizes. Residency time and growth rates for wild fish were comparable with those observed in an estuary without hatchery fish. Potential for interaction between wild and hatchery stocks was greatest in the transition zone, where hatchery fish were most abundant and because hatchery releases occurred when catches of wild fish were highest in this foreshore area.
Perivitelline and Vitelline Potentials in Teleost Eggs as Influenced by Ambient Ionic Strength, Natal Salinity, and Electrode Electrolyte; and the Influence of these Potentials on Cadmium Dynamics within the Egg
Authors: Peterson R. H. , Martin-Robichaud D. J.
Published: June 2008

The differences in perivitelline potential (pvp) recorded from eggs, in dilute ambient salt solutions, when recorded from NaCl- or KCl-filled pipettes are considered to be due mainly to differences in diffusion potentials generated within pipettes. Experiments with Evan's blue (a large, impermeable anion) suggest that anion permeability does not influence the pvp response of freshwater eggs to changes in ambient ionic strength. The pvp of the cod (Gadus morhua) egg became more positive as the ambient medium was diluted rather than more negative, as occurs with eggs of freshwater species. The cod pvp response is attributable to diffusion potentials generated by movement of salt across the chorion. The Atlantic salmon (Salmo salar) perivitelline fluid (pvf) concentrates Cd2+in accordance with the levels predicted by the magnitude of the pvp. The slow rate of pvf Cd2+accumulation is attributed to the presence of two large sinks for Cd2+adsorption bounding the pvf: the embryo and the chorion. The potential difference between the yolk and pvf (vitelline potential) is much less responsive to ambient pH than is the pvp, a probable reflection of the low permeability of the periblast. The above results indicate that pvp may be used to predict equilibrium cation concentration differences between pvf and the ambient medium for freshwater eggs. In marine eggs, the influence of perivitelline colloids on the pvp is negated by the high perivitelline salinity (essentially in equilibrium with ambient salinity).
Aberrant Crystallization of Pollock (Pollachius virens) Otoliths
Authors: Strong M. B. , Neilson J. D. , Hunt J. J.
Published: June 2008

The occurrence of aberrant crystallization in Scotian Shelf pollock (Pollachius virens) sagittae was examined. The crystalline structure of the aberrant form was calcite, in contrast with the usual aragonite. The frequency of abnormal crystallization increased with fish length, and otoliths of fish originating from certain geographic locales had a significantly higher incidence. However, the extent of calcitic crystallization did not increase with fish length and was inversely correlated with frequency of occurrence; completely calcitic otoliths were rarely found. The region where centres of calcitic crystallization most frequently occurred was in the vicinity of the rostrum. While the causal mechanism for the aberrant crystallization could not be identified, it appears likely that to permit the simultaneous deposition of calcite and aragonite, the organic precursor for subsequent crystallization must differ locally on the surface of affected otoliths.
Zooplankton and Fish Accumulate Chlorinated Hydrocarbons from Contaminated Sediments
Authors: Larsson Per
Published: June 2008

Polychlorinated biphenyls (PCBs) originating from the sediment were taken up by zooplankton and fish in artificial ponds in the field. PCB uptake in zooplankton was concentration dependent, as levels of the residues in water varied seasonally. Planktivorous fish accumulated the compounds to high levels at high summer concentrations of PCBs in the water, after which elimination was slow. Levels of PCBs in benthic fishes continuously increased during the 1.5-yr study. The results show that chlorinated hydrocarbons deposited in sediments are available to aquatic organisms.
Characterization of cDNA of lycopene β-cyclase responsible for a high level of β-carotene accumulation inDunaliella salina
Authors: Zhu Yue-Hui , Jiang Jian-Guo , Chen Qian
Published: June 2008

Lycopene β-cyclase (Lyc-B) is the key enzyme in the catalysis of linear lycopene to form cyclic β-carotene, an indispensable part of the photosynthetic apparatus and an important source of vitamin A in human and animal nutrition. Studies showing that the microalga Dunaliella salina can accumulate a high level of β-carotene are lacking. We hypothesize that D. salina is closely involved with the catalytic mechanism of Lyc-B and the molecular regulation of its gene. In this study, we used RT–PCR and RACE–PCR to isolate a 2475 bp cDNA with a 1824 bp open reading frame, encoding a putative Lyc-B, from D. salina. Homology studies showed that the deduced amino acid sequence had a significant overall similarity with sequences of other green algae and higher plants, and that it shared the highest sequence identity, up to 64%, with Lyc-B of Chlamydomonas reinhardtii. Codon analysis showed that synonymous codon usage in the enzyme has a strong bias towards codons ending with adenosine. Two motifs were found in the Lyc-B sequence, one at the N terminus, for binding the hypothetical cofactor FAD, and the other was a substrate carrier motif in oxygenic organisms shared by an earlier carotenogenesis enzyme, phytoene desaturase, and Lyc-B. A tertiary structure prediction suggested that the catalytic or binding site structure within LycB from D. salina is superior to that of both H. pluvialis and C. reinhardtii. The LycB protein from D. salina was quite removed from that of H. pluvialis and C. reinhardtii in the phylogenetic tree. Taken as a whole, this information provides insight into the regulatatory mechanism of Lyc-B at the molecular level and the high level of β-carotene accumulation in the microalga D. salina.
Structure of the O-polysaccharide of the lipopolysaccharide produced by Taylorella asinigenitalis type strain (ATCC 700933)
Authors: Vinogradov Evgeny , MacLean Leann L. , Brooks Brian W. , Lutze-Wallace Cheryl , Perry Malcolm B.
Published: June 2008

Taylorella asinigenitalis sp. nov is a nonpathogenic gram-negative bacterium recently isolated from the genital tract of male donkeys. The bacterium is phenotypically indistinguishable from Taylorella equigenitalis, a pathogen that is the cause of contagious equine metritis, a highly communicable venereal disease of horses. The structural analysis of the lipopolysaccharide produced by T. asinigenitalis sp. nov (ATCC 700933) demonstrated that its O-polysaccharide (O-PS) component is a linear unbranched polymer of repeating disaccharide units composed of 1,3-linked pyranosyl residues of 2,4-diacetamido-2,4-dideoxy-β-d-quinovose (bacillosamine) and 2-acetamidino-2-deoxy-β-d-glucuronic acid, and has the structure [→3)-β-d-QuipNAc4NAc-(1→3)-β-d-GlcpNAmA-(1→]n. The chemical structure and serological characteristics of the T. asinigenitalis O-PS are distinct from those of the O-PS of the T. equigenitalis type strain, thus providing a cell-surface target macromolecule that can be used to distinguish pathogenic from nonpathogenic Taylorella sp. clinical isolates.
Identification of modulating residues defining the catalytic cleft of insulin-regulated aminopeptidase
Authors: Ye Siying , Chai Siew Yeen , Lew Rebecca A. , Ascher David B. , Morton Craig J. , Parker Michael W. , Albiston Anthony L.
Published: June 2008

Inhibition of insulin-regulated aminopeptidase (IRAP) has been demonstrated to facilitate memory in rodents, making IRAP a potential target for the development of cognitive enhancing therapies. In this study, we generated a 3-D model of the catalytic domain of IRAP based on the crystal structure of leukotriene A4 hydrolase (LTA4H). This model identified two key residues at the ‘entrance’ of the catalytic cleft of IRAP, Ala427 and Leu483, which present a more open arrangement of the S1 subsite compared with LTA4H. These residues may define the size and 3-D structure of the catalytic pocket, thereby conferring substrate and inhibitor specificity. Alteration of the S1 subsite by the mutation A427Y in IRAP markedly increased the rate of substrate cleavage V of the enzyme for a synthetic substrate, although a corresponding increase in the rate of cleavage of peptide substrates Leu-enkephalin and vasopressin was was not apparent. In contrast, [L483F]IRAP demonstrated a 30-fold decrease in activity due to changes in both substrate affinity and rate of substrate cleavage. [L483F]IRAP, although capable of efficiently cleaving the N-terminal cysteine from vasopressin, was unable to cleave the tyrosine residue from either Leu-enkephalin or Cyt6-desCys1-vasopressin (2–9), both substrates of IRAP. An 11-fold reduction in the affinity of the peptide inhibitor norleucine1-angiotensin IV was observed, whereas the affinity of angiotensin IV remained unaltered. In additionm we predict that the peptide inhibitors bind to the catalytic site, with the NH2-terminal P1 residue occupying the catalytic cleft (S1 subsite) in a manner similar to that proposed for peptide substrates.
DNase I – DNA interaction alters DNA and protein conformations
Authors: N’soukpoé-Kossi C.N. , Diamantoglou S. , Tajmir-Riahi H.A.
Published: June 2008

Human DNase I is an endonuclease that catalyzes the hydrolysis of double-stranded DNA predominantly by a single-stranded nicking mechanism under physiological conditions in the presence of divalent Mg and Ca cations. It binds to the minor groove and the backbone phosphate group and has no contact with the major groove of the right-handed DNA duplex. The aim of this study was to examine the effects of DNase I – DNA complexation on DNA and protein conformations.We monitored the interaction of DNA with DNase I under physiological conditions in the absence of Mg2+, with a constant DNA concentration (12.5 mmol/L; phosphate) and various protein concentrations (10–250 µmol/L). We used Fourier transfrom infrared, UV-visible, and circular dichroism spectroscopic methods to determine the protein binding mode, binding constant, and effects of polynucleotide–enzyme interactions on both DNA and protein conformations. Structural analyses showed major DNase–PO2binding and minor groove interaction, with an overall binding constant, K, of 5.7 × 105± 0.78 × 105(mol/L)–1. We found that the DNase I – DNA interaction altered protein secondary structure, with a major reduction in α helix and an increase in β sheet and random structures, and that a partial B-to-A DNA conformational change occurred. No DNA digestion was observed upon protein–DNA complexation.
The role of a stand dynamics model in the spruce budworm decision support system
Authors: MacLean David A.
Published: June 2008

Stand dynamics models that predict effects of pests on forest development are key components of pest and forest management planning decision support systems (DSS). Such stand models are required to quantify the marginal effects and costs–benefits of alternative strategies, and thereby to assist in evaluating management options and defining tactics and strategies. The spruce budworm (Choristoneurafumiferana (Clem.)) DSS allows users to project forest inventories under alternative budworm and protection (insecticide use) scenarios, to plan protection programs based on marginal timber supply benefits, to incorporate budworm effects on stand or forest development into management plans, and to evaluate silvicultural and forest management alternatives to limit damage. The STAMAN stand model is an integral part of the spruce budworm DSS, used to calculate stand impact matrices used by two DSS components. Simulations, using STAMAN, for 13 classes of spruce–fir stands under various levels of constant, cumulative defoliation for a 10-year period, resulted in predicted volume reductions of 1–6% with 20% defoliation, 27–42% with 60% defoliation, and 82–99% with 90% defoliation. Another set of simulations using a 30-year cyclical defoliation pattern (including 5 years of light defoliation, 8 years of moderate–severe defoliation, and 17 years of very light or nil defoliation) resulted in volume reductions similar to published data for actual spruce budworm outbreaks.
Chronic ozone effects on three northeastern hardwood species: growth and biomass
Authors: Rebbeck Joanne
Published: June 2008

The response of black cherry (Prunusserotina Ehrh.), sugar maple (Acersacchárum Marsh.), and yellow-poplar (Liriodendrontulipifera L.) seedlings after being exposed to two seasons of ozone ranging from subambient to twice ambient (exposures ranged from 16 to 107 ppm•h in 1990 and 31 to 197 ppm•h in 1991) was studied in standard 3-m diameter open-top chambers. All three species responded differently to ozone. After one season of exposure, black cherry growth and biomass decreased with increasing ozone exposure; yellow-poplar growth and biomass increased with increasing ozone exposure; and sugar maple growth and biomass were not significantly affected by ozone. After two seasons of exposure, few to no effects from ozone were observed in either sugar maple or yellow-poplar. However, total plant and root biomass of black cherry exposed to twice ambient ozone were reduced 32 and 39%, respectively, when compared with those grown in charcoal-filtered air. Exposure–response relationships were either linear or quadratic for most of the growth and biomass parameters measured.