Priority assessment of toxic substances in life cycle assessment. Part II: assessing parameter uncertainty and human variability in the calculation of toxicity potentials

Toxicity potentials are standard values used in life cycle assessment (LCA) to enable a comparison of toxic impacts between substances. This paper presents the results of an uncertainty assessment of toxicity potentials that were calculated with the global nested multi-media fate, exposure and effects model USES-LCA. The variance in toxicity potentials resulting from input parameter uncertainties and human variability was quantified by means of Monte Carlo analysis with Latin Hypercube sampling (LHS). For Atrazine, 2,3,7,8-TCDD and Lead, variation, expressed by the ratio of the 97.5%-ile and the 2.5%-ile, ranges from about 1.5 to 6 orders of magnitude. The major part of this variation originates from a limited set of substance-specific input parameters, i.e. parameters that describe transport mechanisms, substance degradation, indirect exposure routes and no-effect concentrations. Considerable correlations were found between the toxicity potentials of one substance, in particular within one impact category. The uncertainties and correlations reported in the present study may have a significant impact on the outcome of LCA case studies.     

Mexican High Rubber Producing Guayule Shrubs: A Potential Source for Commercial Development

Guayule is a shrub native to Mexico growing in semiarid lands, that may be incorporated into the semiarid region production system as a complement for annual crops. The possibility to develop this natural resource as a sustainable industrial source of natural rubber, may improve the socio-economical level of people living at the guayule region and favor the agricultural development near the US-Mexico border. Despite the existence of natural stands in Mexico with guayule plants of different rubber content, a program envisaging selection of plants with high rubber synthesis potential joined to agronomic management practices are required. This could achieve the rubber yield needed to guarantee a constant supply of raw material for an industrial processing plant. This paper reviews R&D work carried out in Mexico for the last 25 years, including genetic aspects and evaluation of guayule response to environmental and agronomic factors. Relevant results showed plants with up to 21% rubber content and the existence of diploid plants, which could facilitate future plant breeding programs.     

2005年中国大陆地震灾害损失述评

在列出2005年中国5级以上地震目录的基础上，结合有关省（自治区、直辖市）地震局的地震灾害评估资料，总结了2005年中国大陆地震灾害的主要数据和特性。最后列出了1990—2005年中国大陆地震灾害的相应数据，并进行了简要的比较。     

Buffer capacity of seawater at high pCO2

Measurements of the variation of the carbon dioxide partial pressure in water were performed up to pCO₂ and CO₂ using 6.000 ppm. The consistent data so far obtained were compared with calculated pCO₂ using the Lynan constants. A plot of the experimental and calculated data evidences that comparisons are only possible by using varying carbonate alkalinity.     

A note on the development of the thermocline in temperate lakes

An exact solution has been obtained for a non-linear partial differential equation governing the vertical transport of heat in a lake. The equation, derived and analyzed numerically by Sundaram and Rehm (1971, 1973) is based on a balance between thermal buoyany forces and wind induced turbulence. The exact solution displays the qualitative features of the numerical solution and its representation of the seasonal descent of the thermocline is accurate.     

RESIDENTIAL WATER DEMAND: A POOLED,TIME SERIES,CROSS SECTION STUDY OF MALMÖ, SWEDEN1

Shortcoming associated with past water demand studies are evaluated. To overcome these shortcomings, pooled, time series, cross section data from -6, Sweden, are used in an ordinary Least squares analysis to estimate the demand for residential water. Elasticities for five variables, including price and income, are estimated. An approach for the conduct of future water demand studies is suggested.     

First-trimester maternal serum human thyroid-stimulating hormone in chromosomally normal and Down syndrome pregnancies

Maternal serum human thyroid-stimulating hormone (TSH) levels were investigated in chromosomally normal and Down syndrome pregnancies to determine whether TSH can be used as a marker for Down syndrome in the first trimester. Measurements were conducted on stored serum samples collected from 23 Down syndrome pregnancies and 115 unaffected pregnancies before chorionic villus sampling (CVS), between 9 and 11 completed weeks of pregnancy. The samples were matched for gestational age, maternal age, maternal weight and duration of storage of the serum sample. Maternal TSH concentration was slightly decreased in Down syndrome pregnancies, with a median of 0.84 multiples of the median (MoM). Maternal serum human chorionic gonadotropin (hCG) concentration was slightly elevated in Down syndrome pregnancies, with a median of 1.03 MoM. Both differences were not significant applying matched rank analysis (p=0.50 for TSH and p=0.43 for hCG). The association between TSH and hCG in unaffected pregnancies was also measured. The Spearman correlation coefficient between TSH and hCG was −0.21 which was statistically significant (p=0.02, 95% confidence interval −0.38 to −0.03). However, it was concluded that TSH is not a useful marker for distinguishing Down syndrome-affected pregnancies from normal pregnancies in the first trimester. Copyright © 2001 John Wiley & Sons, Ltd.