Prenatal diagnosis of trisomy 10 p in a twin pregnancy

A twin pregnancy with trisomy 10 p due to a paternal 10;12 translocation is reported. The prenatal diagnosis steps followed in twin pregnancies are reviewed and the concordant features of trisomy 10 p seen in both fetuses confirm previous reports on the clinical features of this chromosomal defect.     

Modelling the Choice Between Multiple-Use vs. Specialised Forest Management and its Impact on Forest Management Costs

Forests provide ecosystem services, including timber production. In some cases, private forest owners perform management actions in order to enhance the provision of such services, or they may be encouraged by public policies and payments. This paper focuses specifically on the decision to set forest land aside for biodiversity conservation, as part of the more general question of the efficiency of multiple-use vs. specialised management of forest lands. We propose an econometric analysis to identify factors in the set-aside choice and measure the impact of this decision on forest management costs. The results show that the set-aside choice depends on the landowners’ income and motivations related to forest amenities. The choice of specialised management, as reflected in the set-aside decision, has a significant and positive impact on the intensity of management in the remainder of the forest and on management costs. From a policy implications point of view, these results suggest that instruments such as forest certification, subsidies and reverse auctions for conservation will be most likely to attract the interest of those forest owners with personal motivations and forest properties that offer both benefit and cost advantages in opting for such specialised management strategies.

     

Atmospheric Polycyclic Aromatic Hydrocarbons at a Point Source of Emissions. Part A: Identification and Determination of Polycyclic Aromatic Compounds in Airborne Particulate Matter Near a Horizontal Stud Soderberg Plant

Abstract

This paper summarizes the sampling and analytical methods developed to identify and measure polycyclic aromatic hydrocarbons (PAH) and related aromatic compounds near a Horizontal Stud Soderberg plant at Jonquiere, Quebec, Canada. The primary source of PAH is the coal tar pitch used as a binder in Soderberg anodes. Twice a week at a number of sampling sites, airborne particulate matter was collected on glass-fiber filters using a Hi-Vol sampler for a twenty-four hour period. Organics on the filter were Soxhlet extracted with benzene.

Identification was done by gas chromatography-mass spectrometry (GC-MS). The vast majority of compounds present were PAH, but small amounts of alkyl PAH and polycyclic aromatic compounds with heteroatoms such as nitrogen, oxygen and sulfur were also identified. Based on the GC-MS identification, a group of 14 PAH was selected for monitoring. Frequent PAH determinations revealed that the ratio of Benzo(a- )Pyrene to total PAH on the Hi-Vol filters is relatively constant in ambient air from one sampling station to another.     

Contrasted dynamics of northern Labrador tree lines caused by climate change and migrational lag

The northern Québec-Labrador tree lines are the most climatically stressed tree ecosystems of eastern North America. In particular, white spruce (Picea glauca) tree line populations distributed between 56 degrees N and 58 degrees N and 61 degrees W and 66 degrees W show contrasted responses to recent changes in climate according to their geographic position relative to the Labrador Sea. Along the coast, the northernmost latitudinal and altitudinal tree lines responded positively to warming over the last 50 years with invading spruce several tens of meters above the current tree line. In contrast, white spruce tree lines across the wind-exposed Labrador plateau are located much higher in altitude and have receded a few tens of meters beginning around AD 1740-1750 and have not yet recovered. Whereas no field evidence of recent fire and insect damage was found, all inland tree line stands were progressively damaged likely due to mechanical defoliation of wind-exposed trees. Massive tree death in the 19th century caused a reduction in the number of seed-bearing trees, and declining tree lines were not replenished by seedlings. Recent warming reported for northern latitudes has not been strong enough to change the regressive tree line trajectory in interior Labrador. However, white spruce expansion above coastal tree line in the northernmost forest site in Labrador is in line with current climatic trends. It is hypothesized that the species is still advancing toward its potential tree line higher in altitude due to delayed postglacial migration. The slow advance of white spruce in northernmost coastal Labrador is likely caused by the rugged topography of the Torngat-Kaumajet-Kiglapait mountains.     

石油烃厌氧生物降解代谢产物研究进展

石油烃厌氧生物降解代谢产物的分析对于石油烃厌氧降解机制的研究、功能微生物的筛选以及微生物活动的原位监测具有指示性作用.综述了近年来石油烃厌氧生物降解代谢产物的研究进展.石油烃厌氧降解的初始活化方式主要包括脱氢羟基化、加延胡索酸以及羧化等.其中,加延胡索酸是不同种类的微生物通常采用的代谢方式.同时,将代谢产物按照气体、无机离子和有机酸进行分类,并针对各类物质特别是瞬时性、低浓度的有机酸类产物常采用的分析方法进行归纳.通过实例强调了代谢产物作为潜在生物标记物的应用,并对石油烃厌氧降解代谢产物分析方法的发展提出展望.图3参58     

Acanthochromis polyacanthus,a fish lacking larval dispersal,has genetically differentiated populations at local and regional scales on the Great Barrier Reef

Acanthochromis Gill is a monotypic genus within the damselfish family Pomacentridae, erected for an unusual species [A. polyacanthus (Bleeker)] that uniquely lacks larval dispersal. Instead, offspring are reared in the parental territory, in the manner of cichlids, and fledged into the surrounding habitat. Phenotypic and genotypic variation was surveyed on the basis of body colouration and 7 polymorphic loci in 19 populations from 5 regions of the central and southern Great Barrier Reef (GBR). Variation in both characters was found at regional and local scales. Two colour morphs were recognised: a bicoloured morph from the three northern regions and a uniform dark morph from the two southern regions. Isozyme analysis showed a similar pattern with greatest variation between the different morphs, but also with significant variation at both regional and local scales within morphotypes. Heterozygosity was maximal in the central populations, which, together with other measures of variability, suggests a mixing of separate gene pools in this region and denies species status to the two morphotypes despite numerous fixed differences in allele frequencies between the most distant populations. The presence of fixed differences in multiple alleles between populations separated by 1000 km indicates negligible gene flow over such distances and long isolation of these gene pools. These patterns may reflect recolonisation of the GBR after the last sea-level rise by fish from two stocks. Founder effects and random drift in small populations after colonisation are probably the major sources of the local and regional variations observed at smaller spatial scales. This diversity has been maintained among populations at all scales by the very low levels of gene flow possible without an effective strategy for larval dispersal between coral reefs.     

Lessons learnt from a participatory integrated assessment of greenhouse gas emission reduction options in firms

This article discusses an approach for identification and evaluation of short-term greenhouse gas (GHG) emission reduction options in firms. The approach is based on lessons learnt from a project using Participatory Integrated Assessment (PIA) and builds on the idea that effective public climate policy for firms requires options that have support from stakeholders and are practically feasible. Scenarios are used to provide a link with short-term policy developments and a model assists to communicate quantitative effects of options to participating stakeholders. Our approach can be seen as a first step towards a framework that meets the need for more systematic approaches to PIAs identifying effective public policies for short-term GHG emission reduction options in firms. In order to identify effective options for non-carbon dioxide GHG emission reductions, our approach has been applied to Dutch dairy farms, after which it has been refined. The case study suggests that our approach can provide balance between practical, context specific issues and scientific-theoretical aspects, thereby avoiding common pitfalls of participatory research projects to focus too much on either theory or practical issues.

Understanding nutrient build-up on urban road surfaces

This article discusses the outcomes of a research project on nutrients build-up on urban road surfaces.Nutrient build-up was investigated on road sites belonging to residential,industrial and commercial land use.Collected build-up samples were separated into five particle size ranges and were tested for total nitrogen (TN),total phosphorus (TP) and sub species of nutrients,namely,NO 2- ,NO 3- ,TKN and PO 43-.Multivariate analytical techniques were used to analyse the data and to develop detailed understanding on build- up.Data analysis revealed that the solids loads on urban road surfaces are highly influenced by factors such as land use,antecedent dry period and traffic volume.However,the nutrient build-up process was found to be independent of the type of land use.It was solely dependent on the particle size of solids build-up.Most of the nutrients were associated with the particle size range 150 μm.Therefore,the removal of particles below 150 μm from road surfaces is of importance for the removal of nitrogen and phosphorus from road surface solids build-up.It is also important to consider the difference in the composition of nitrogen and phosphorus build-up in the context of designing effective stormwater quality mitigation strategies.     

Elaboration of a Bio-Colored Material Based on Natural Dye and Polybutylene Succinate: Comparative Study with Colored Polylactic Acid

Journal of Polymers and the Environment - In the context of sustainable development and natural products valorization, new ecological materials enter a logic aimed at removing the causes of...     

Thermal treatment of plasma-synthesized goethite improves Fenton-like degradation of orange II dye

Various iron oxides are used for Fenton reactions to degrade organic pollutants. The degradation efficiency may be improved by transforming an iron oxide phase to another. Here, we report on the transformation of goethite into hematite by thermal treatment at 400 °C. The products were analyzed by X-ray diffractometry, Raman spectroscopy, scanning electron microscopy and N₂-physisorption. The catalytic activities were measured for orange II bleaching at initial concentration of 25 mg L^?1, pH 3, catalyst concentration of 0.2 g L^?1; 5 mM H₂O₂, 30 °C. Results show that the synthesized goethite was successfully transformed into hematite, and the specific surface area of the material increased from 134 to 163 m² g^?1. The bleaching efficiency of the orange II dye reached 100 % for the hematite product, versus 78 % for goethite. Therefore, a moderate thermal treatment of a plasma-synthesized goethite improves the catalytic oxidation of organic pollutants.