Cleft palate: Confirmation of prenatal diagnosis by colour Doppler ultrasound

We present a case of a twin with trisomy 47,XX+i(9p) in whom the diagnosis of cleft palate was confirmed by colour Doppler imaging demonstrating abnormal fluid flow across the fetal pharyngeal bone defect. Application of this technique in cases predisposed for this congenital lesion may prove beneficial in the diagnosis of the more subtle types of isolated cleft palate.     

Why slaughter? The cultural dimensions of Britain's foot and mouth disease control policy, 1892–2001

In 1892, the British agricultural authorities introduced a policy of slaughtering animals infected with foot and mouth disease (FMD). This measure endured throughout the 20th century and formed a base line upon which officials superimposed the controversial "contiguous cull" policy during the devastating 2001 epidemic. Proponents of the slaughter frequently emphasized its capacity to eliminate FMD from Britain, and claimed that it was both cheaper and more effective than the alternative policies of isolation and vaccination. However, their discussions reveal that a less obvious but nonetheless important reason for maintaining the slaughter policy was the conviction that in its manner of operation and its outcomes, it benefited the state and status of the British nation. To its supporters, slaughter was far more than a method of disease control; it acted also as a moralizing and civilizing force, an indicator of veterinary ability and a "virility symbol" of British international leadership. This "cultural" rationale for FMD control by slaughter declined during the late 20th century and was wholly undermined by the 2001 epidemic, when extensive culling failed to convey the intended image of an organized, enlightened Britain.     

Calibration of the forest vegetation simulator (FVS) model for the main forest species of Ontario,Canada

The forest vegetation simulator (FVS) model was calibrated for use in Ontario, Canada, to predict the growth of forest stands. Using data from permanent sample plots originating from different regions of Ontario, new models were derived for dbh growth rate, survival rate, stem height and species group density index for large trees and height and dbh growth rate for small trees. The dataset included black spruce (Picea mariana (Mill.) B.S.P.) and jack pine (Pinus banksiana Lamb.) for the boreal region, sugar maple (Acer saccharum Marsh.), white pine (Pinus strobus L.), red pine (Pinus resinosa Ait.) and yellow birch (Betula alleghaniensis Britton) for the Great Lakes-St. Lawrence region, and balsam fir (Abies balsamea (L.) Mill.) and trembling aspen (Populus tremuloides Michx.) for both regions. These new models were validated against an independent dataset that consisted of permanent sample plots located in Quebec. The new models predicted biologically consistent growth patterns whereas some of the original models from the Lake States version of FVS occasionally did not. The new models also fitted the calibration (Ontario) data better than the original FVS models. The validation against independent data from Quebec showed that the new models generally had a lower prediction error than the original FVS models.     

Stress responses of Calluna vulgaris to reduced and oxidised N applied under 'real world conditions'

Effects and implications of reduced and oxidised N, applied under 'real world' conditions, since May 2002, are reported for Calluna growing on an ombrotrophic bog. Ammonia has been released from a 10 m line source generating monthly concentrations of 180-6 microg m(-3), while ammonium chloride and sodium nitrate are applied in rainwater at nitrate and ammonium concentrations below 4mM and providing up to 56 kg N ha(-1) year(-1) above a background deposition of 10 kg N ha(-1) year(-1). Ammonia concentrations, >8 microg m(-3) have significantly enhanced foliar N concentrations, increased sensitivity to drought, frost and winter desiccation, spring frost damage and increased the incidence of pathogen outbreaks. The mature Calluna bushes nearest the NH3 source have turned bleached and moribund. By comparison the Calluna receiving reduced and oxidised N in rain has shown no significant visible or stress related effects with no significant increase in N status.     

Seasonal bioavailability of sediment-associated heavy metals along the Mississippi river floodplain.

A value of simultaneously extracted metal to acid-volatile sulfide (SEM-AVS) can provide important information regarding metal availability in anaerobic sediment. SEM and AVS concentrations were obtained by the cold-acid purge-and-trap technique during spring and summer at six locations along the Mississippi River floodplain. SEM-AVS values and AVS concentrations did not vary significantly between locations during both seasons. AVS concentrations were significantly greater during summer than spring, resulting in significantly lower SEM-AVS values in summer. Total SEM concentrations did not significantly vary between seasons or specific locations. SEM-AVS values were greater than one at each location during both seasons. Sediment metal toxicity was predicted to be absent for benthic organisms along the river floodplain.     

REGIONAL CHARACTERISTICS OF NUTRIENT CONCENTRATIONS IN STREAMS AND THEIR APPLICATION TO NUTRIENT CRITERIA DEVELOPMENT1

ABSTRACT: In order to establish meaningful nutrient criteria, consideration must be given to the spatial variations in geographic phenomena that cause or reflect differences in nutrient concentrations in streams. Regional differences in stream nutrient concentrations were illustrated using stream data collected from 928 nonpoint‐source watersheds distributed throughout the country and sampled as part of the U.S. EPA National Eutrophication Survey (NES). Spatial patterns in the differences were compared and found to correspond with an a priori regional classification system based on regional patterns in landscape attributes associated with variation in nutrient concentrations. The classification consists of 14 regions composed of aggregations of the 84 U.S. EPA Level III Ecoregions. The primary distinguishing characteristics of each region and the factors associated with variability in water quality characteristics are presented. The use of the NES and many other extant monitoring data sets to develop regional reference conditions for nutrient concentrations in streams is discouraged on the basis of sample representation. The necessity that all sites used in such an effort be regionally representative and consistently screened for least possible impact is emphasized. These sampling issues are rigorously addressed by the U.S. EPA Environmental Monitoring and Assessment Program (EMAP). A case‐study, using EMAP data collected from the Central and Eastern Forested Uplands, demonstrates how regional reference conditions and draft nutrient criteria could be developed.     

A TECHNIQUE FOR MEASURING RAINFALL POTENTIAL1

ABSTRACT The roles played by thermodynamic stability and precipitable water in the production of rainfall are of prime importance. These two variables have been combined into a “Rainfall Potential” function by the use of multivariate statistical techniques. Data from weather stations in southern New Mexico and southwest Texas were used in the study. The results appear promising for further investigation, possibly in relation to the occurrence of rare but extremely heavy rains     

The effects of multiple metal contamination on ectomycorrhizal Scots pine (Pinus sylvestris) seedlings

Experiments were conducted to investigate the effects of single and multiple metal contamination (Cd, Pb, Zn, Sb, Cu) on Scots pine seedlings colonised by ectomycorrhizal (ECM) fungi from natural soil inoculum. Seedlings were grown in either contaminated field soil from the site of a chemical accident, soils amended with five metals contaminating the site, or in soil from an uncontaminated control site. Although contaminated and metal-amended soil significantly inhibited root and shoot growth of the Scots pine seedlings, total root tip density was not affected. Of the five metals tested in amended soils, Cd was the most toxic to ECM Scots pine. Field-contaminated soil had a toxic effect on ECM fungi associated with Scots pine seedlings and caused shifts in ECM species composition on ECM seedlings. When compared to soils amended with only one metal, soils amended with a combination of all five metals tested had lower relative toxicity and less accumulation of Pb, Zn and Sb into seedlings. This would indicate that the toxicity of multiple metal contamination cannot be predicted from the individual toxicity of the metals investigated.